WorldWideScience

Sample records for coastal dune community

  1. Effects of Trampling Limitation on Coastal Dune Plant Communities

    Science.gov (United States)

    Santoro, Riccardo; Jucker, Tommaso; Prisco, Irene; Carboni, Marta; Battisti, Corrado; Acosta, Alicia T. R.

    2012-03-01

    Sandy coastlines are sensitive ecosystems where human activities can have considerable negative impacts. In particular, trampling by beach visitors is a disturbance that affects dune vegetation both at the species and community level. In this study we assess the effects of the limitation of human trampling on dune vegetation in a coastal protected area of Central Italy. We compare plant species diversity in two recently fenced sectors with that of an unfenced area (and therefore subject to human trampling) using rarefaction curves and a diversity/dominance approach during a two year study period. Our results indicate that limiting human trampling seems to be a key factor in driving changes in the plant diversity of dune systems. In 2007 the regression lines of species abundance as a function of rank showed steep slopes and high Y-intercept values in all sectors, indicating a comparable level of stress and dominance across the entire study site. On the contrary, in 2009 the regression lines of the two fenced sectors clearly diverge from that of the open sector, showing less steep slopes. This change in the slopes of the tendency lines, evidenced by the diversity/dominance diagrams and related to an increase in species diversity, suggests the recovery of plant communities in the two fences between 2007 and 2009. In general, plant communities subject to trampling tended to be poorer in species and less structured, since only dominant and tolerant plant species persisted. Furthermore, limiting trampling appears to have produced positive changes in the dune vegetation assemblage after a period of only two years. These results are encouraging for the management of coastal dune systems. They highlight how a simple and cost-effective management strategy, based on passive recovery conservation measures (i.e., fence building), can be a quick (1-2 years) and effective method for improving and safeguarding the diversity of dune plant communities.

  2. Mediterranean coastal dune systems: Which abiotic factors have the most influence on plant communities?

    Science.gov (United States)

    Ruocco, Matteo; Bertoni, Duccio; Sarti, Giovanni; Ciccarelli, Daniela

    2014-08-01

    Mediterranean coastal dunes are dynamic and heterogeneous ecosystems characterised by a strong interaction between abiotic and biotic factors. The present study aimed to adopt a multidisciplinary approach - integrating data on dune morphology, sediment texture and soil parameters as well as shoreline trend - in order to define which are the abiotic factors that most affect the distribution and composition of Mediterranean plant dune communities. The study was carried out in two protected areas, located in central Italy, subjected to different shoreline trends in recent years. 75 plots were identified along eleven randomly positioned cross-shore transects, starting from the beach continuing up to the plant communities of the backdunes. In each plot floristic and environmental data - such as distance to the coastline, plot altitude, inclination, shoreline trend, mean grain-size, sorting, pH, conductivity and organic matter concentration - were collected. The analyses revealed significant changes of vegetational cover, dune morphology and geopedological features along the coast-to-inland gradient. Relationships between vegetation composition and environmental factors were investigated through Canonical Correspondence Analysis (CCA). Four factors - distance to the coastline, mean grain-size, shoreline trend and organic matter - were found to be closely correlated with the floristic composition of plant communities. Finally, soil properties were highlighted as the most determinant factors of community zonation in these Mediterranean coastal dune ecosystems. These results could be taken into account by local managers in conservation actions such as protecting the eroding foredunes as well as in artificial dune reconstructions.

  3. Linking restoration ecology with coastal dune restoration

    Science.gov (United States)

    Lithgow, D.; Martínez, M. L.; Gallego-Fernández, J. B.; Hesp, P. A.; Flores, P.; Gachuz, S.; Rodríguez-Revelo, N.; Jiménez-Orocio, O.; Mendoza-González, G.; Álvarez-Molina, L. L.

    2013-10-01

    Restoration and preservation of coastal dunes is urgently needed because of the increasingly rapid loss and degradation of these ecosystems because of many human activities. These activities alter natural processes and coastal dynamics, eliminate topographic variability, fragment, degrade or eliminate habitats, reduce diversity and threaten endemic species. The actions of coastal dune restoration that are already taking place span contrasting activities that range from revegetating and stabilizing the mobile substrate, to removing plant cover and increasing substrate mobility. Our goal was to review how the relative progress of the actions of coastal dune restoration has been assessed, according to the ecosystem attributes outlined by the Society of Ecological Restoration: namely, integrity, health and sustainability and that are derived from the ecological theory of succession. We reviewed the peer reviewed literature published since 1988 that is listed in the ISI Web of Science journals as well as additional references, such as key books. We exclusively focused on large coastal dune systems (such as transgressive and parabolic dunefields) located on natural or seminatural coasts. We found 150 articles that included "coastal dune", "restoration" and "revegetation" in areas such as title, keywords and abstract. From these, 67 dealt specifically with coastal dune restoration. Most of the studies were performed in the USA, The Netherlands and South Africa, during the last two decades. Restoration success has been assessed directly and indirectly by measuring one or a few ecosystem variables. Some ecosystem attributes have been monitored more frequently (ecosystem integrity) than others (ecosystem health and sustainability). Finally, it is important to consider that ecological succession is a desirable approach in restoration actions. Natural dynamics and disturbances should be considered as part of the restored system, to improve ecosystem integrity, health and

  4. Coastal Dunes of the Baltic Sea Shores: A Review

    Directory of Open Access Journals (Sweden)

    Łabuz Tomasz Arkadiusz

    2018-03-01

    Full Text Available The article summarises results of studies conducted along the Baltic Sea sandy coasts by scientists involved in coastal dune research, and presents an attempt to describe the types and distribution of dune coasts. The Baltic Sea coasts feature lower and higher foredunes. The lowland behind the coastal dune belt is covered by wandering or stabilised inland dunes – transgressive forms, mainly parabolic or barchans. The source of sediment for dune development includes fluvioglacial sands from eroded coasts, river-discharged sand, and older eroded dunes. Due to the ongoing erosion and coastal retreat, many dunes have been eroded, and some are withdrawing onto the adjacent land. There are visible differences between the south-eastern, western, and northern parts of the Baltic Sea coast with respect to dune development. The entire southern and eastern coast abounds in sand, so the coastal dunes are large, formerly or currently wandering formations. The only shifting dunes are found at the Polish and the Russian–Lithuanian coasts on the Łebsko Lake Sandbar as well as on the Vistula and Curonian Spits. The very diverse shoreline of the south-western coast experiences a scarcity of larger sandy formations. Substantial parts of the Baltic Sea sandy coasts have been eroded or transformed by humans. The northern part of the Baltic Sea coast features mainly narrow and low sandy coasts (e.g. in Estonia. Further north, sandy dunes are virtually absent.

  5. A meta-analysis of plant facilitation in coastal dune systems: responses, regions, and research gaps.

    Science.gov (United States)

    Castanho, Camila de Toledo; Lortie, Christopher J; Zaitchik, Benjamin; Prado, Paulo Inácio

    2015-01-01

    Empirical studies in salt marshes, arid, and alpine systems support the hypothesis that facilitation between plants is an important ecological process in severe or 'stressful' environments. Coastal dunes are both abiotically stressful and frequently disturbed systems. Facilitation has been documented, but the evidence to date has not been synthesized. We did a systematic review with meta-analysis to highlight general research gaps in the study of plant interactions in coastal dunes and examine if regional and local factors influence the magnitude of facilitation in these systems. The 32 studies included in the systematic review were done in coastal dunes located in 13 countries around the world but the majority was in the temperate zone (63%). Most of the studies adopt only an observational approach to make inferences about facilitative interactions, whereas only 28% of the studies used both observational and experimental approaches. Among the factors we tested, only geographic region mediates the occurrence of facilitation more broadly in coastal dune systems. The presence of a neighbor positively influenced growth and survival in the tropics, whereas in temperate and subartic regions the effect was neutral for both response variables. We found no evidence that climatic and local factors, such as life-form and life stage of interacting plants, affect the magnitude of facilitation in coastal dunes. Overall, conclusions about plant facilitation in coastal dunes depend on the response variable measured and, more broadly, on the geographic region examined. However, the high variability and the limited number of studies, especially in tropical region, indicate we need to be cautious in the generalization of the conclusions. Anyway, coastal dunes provide an important means to explore topical issues in facilitation research including context dependency, local versus regional drivers of community structure, and the importance of gradients in shaping the outcome of net

  6. A meta-analysis of plant facilitation in coastal dune systems: responses, regions, and research gaps

    Directory of Open Access Journals (Sweden)

    Camila de Toledo Castanho

    2015-02-01

    Full Text Available Empirical studies in salt marshes, arid, and alpine systems support the hypothesis that facilitation between plants is an important ecological process in severe or ‘stressful’ environments. Coastal dunes are both abiotically stressful and frequently disturbed systems. Facilitation has been documented, but the evidence to date has not been synthesized. We did a systematic review with meta-analysis to highlight general research gaps in the study of plant interactions in coastal dunes and examine if regional and local factors influence the magnitude of facilitation in these systems. The 32 studies included in the systematic review were done in coastal dunes located in 13 countries around the world but the majority was in the temperate zone (63%. Most of the studies adopt only an observational approach to make inferences about facilitative interactions, whereas only 28% of the studies used both observational and experimental approaches. Among the factors we tested, only geographic region mediates the occurrence of facilitation more broadly in coastal dune systems. The presence of a neighbor positively influenced growth and survival in the tropics, whereas in temperate and subartic regions the effect was neutral for both response variables. We found no evidence that climatic and local factors, such as life-form and life stage of interacting plants, affect the magnitude of facilitation in coastal dunes. Overall, conclusions about plant facilitation in coastal dunes depend on the response variable measured and, more broadly, on the geographic region examined. However, the high variability and the limited number of studies, especially in tropical region, indicate we need to be cautious in the generalization of the conclusions. Anyway, coastal dunes provide an important means to explore topical issues in facilitation research including context dependency, local versus regional drivers of community structure, and the importance of gradients in shaping

  7. Fine-scale patterns of vegetation assembly in the monitoring of changes in coastal sand-dune landscapes

    Directory of Open Access Journals (Sweden)

    J. Honrado

    2010-02-01

    Full Text Available Understanding dune ecosystem responses to multi-scale environmental changes can provide the framework for reliable forecasts and cost-efficient protocols for detecting shifts in prevailing coastal dynamics. Based on the hypothesis that stress and disturbance interact as primary community controls in coastal dunes, we studied the fine-scale floristic assembly of foredune vegetation, in its relation to topography, along regional and local environmental gradients in the 200 km long coastline of northern Portugal, encompassing a major biogeographic transition in western Europe. Thirty topographic profiles perpendicular to the shoreline were recorded at ten sites along the regional climate gradient, and vegetation was sampled by recording the frequency of plant species along those profiles. Quantitative topographic attributes of vegetated dune profiles (e.g. length or height exhibited wide variations relatable to differences in prevailing coastal dynamics. Metrics of taxonomic diversity (e.g. total species richness and its additive beta component and of the functional composition of vegetation were highly correlated to attributes of dune topography. Under transgressive dynamics, vegetation profiles have fewer species, increased dominance, lower turnover rates, and lower total vegetation cover. These changes may drive a decrease in structural and functional diversity, with important consequences for resistance, resilience and other ecosystem properties. Moreover, differences in both vegetation assembly (in meta-stable dunes and response to increased disturbance (in eroding dunes between distinct biogeographic contexts highlight a possible decline in facilitation efficiency under extreme physical stress (i.e. under Mediterranean climate and support the significance of functional approaches in the study of local ecosystem responses to disturbance along regional gradients. Our results strongly suggest that assessing fine-scale community assembly can

  8. Changes of Bulgarian Coastal Dune Landscape under Anthropogenic Impact

    Science.gov (United States)

    Palazov, A.; Young, R.; Stancheva, M.; Stanchev, H.

    2012-04-01

    At one time large sand dune formations were widely distributed along the Bulgarian coast. However, due to increased urbanization in the coastal zone, the areas of total dune landscape has been constantly reduced. Dunes presently comprise only 10% of the entire 412 km long coastline of Bulgaria: they embrace a total length of 38.57 km and a total area of 8.78 km2 Important tasks in dune protection are identification of landscape changes for a certain period of time and accurate delineation of sand dune areas. The present research traces sand dune changes along the Bulgarian Black Sea coast over a 27 year period (1983-2010). This period includes also the time of expanded tourist boom and overbuilding of the coastal zone, and respectively presents the largest dune changes and reductions. Based on the landscape change analyst in GIS environment the study also aims to explore the importance of different natural and human factors in driving the observed dune alterations and destruction. To detect and assess dune changes during the last 3 decades, we used data for sand dunes derived from several sources at different time periods in order to compare changes in shoreline positions, dune contours and areas: i) Topographic maps in 1:5,000 scale from 1983; ii) Modern Very High Resolution orthophotographs from 2006 and 2010; iii) QuickBird Very High Resolution satellite images from 2009; iv) Statistical information for population and tourist infrastructure is also used to consider the influence of human pressure and hotel developments on the dune dynamics. In addition, for more detailed description and visualization of main dune types, digital photos have been taken at many parts of the Bulgarian coast. The study was performed in GIS environment. Based on the results obtained the dunes along the Bulgarian coast were divided into three main groups with relation to the general factors responsible for their alterations: i) Dunes that have decreased in result of shoreline retreat

  9. Probabilistic estimation of dune erosion and coastal zone risk

    NARCIS (Netherlands)

    Li, F.

    2014-01-01

    Coastal erosion has gained global attention and has been studied for many decades. As a soft sea defence structure, coastal sandy dunes protect coastal zones all over the world, which usually are densely populated areas with tremendous economic value. The coastal zone of the Netherlands, one of the

  10. Biological Soil Crusts from Coastal Dunes at the Baltic Sea: Cyanobacterial and Algal Biodiversity and Related Soil Properties.

    Science.gov (United States)

    Schulz, Karoline; Mikhailyuk, Tatiana; Dreßler, Mirko; Leinweber, Peter; Karsten, Ulf

    2016-01-01

    Biological soil crusts (BSCs) are known as "ecosystem-engineers" that have important, multifunctional ecological roles in primary production, in nutrient and hydrological cycles, and in stabilization of soils. These communities, however, are almost unstudied in coastal dunes of the temperate zone. Hence, for the first time, the biodiversity of cyanobacterial and algal dominated BSCs collected in five dunes from the southern Baltic Sea coast on the islands Rügen and Usedom (Germany) was investigated in connection with physicochemical soil parameters. The species composition of cyanobacteria and algae was identified with direct determination of crust subsamples, cultural methods, and diatom slides. To investigate the influence of soil properties on species composition, the texture, pH, electrical conductivity, carbonate content, total contents of carbon, nitrogen, phosphorus, and the bioavailable phosphorus-fraction (PO4 (3-)) were analyzed in adjacent BSC-free surface soils at each study site. The data indicate that BSCs in coastal dunes of the southern Baltic Sea represent an ecologically important vegetation form with a surprisingly high site-specific diversity of 19 cyanobacteria, 51 non-diatom algae, and 55 diatoms. All dominant species of the genera Coleofasciculus, Lyngbya, Microcoleus, Nostoc, Hydrocoryne, Leptolyngbya, Klebsormidium, and Lobochlamys are typical aero-terrestrial cyanobacteria and algae, respectively. This first study of coastal sand dunes in the Baltic region provides compelling evidence that here the BSCs were dominated by cyanobacteria, algae, or a mixture of both. Among the physicochemical soil properties, the total phosphorus content of the BSC-free sand was the only factor that significantly influenced the cyanobacterial and algal community structure of BSCs in coastal dunes.

  11. Provenance of Coastal dune sands along Red Sea, Egypt

    Indian Academy of Sciences (India)

    26

    accumulation of sands behind vegetation or any other obstacles. ... The study areas Safaga (SF) and Quseir (QS) field dunes (Fig. 1) ..... coastal dune sands were deposited in a passive margin of a synrift .... Sed Petrol 63(6), 1110-1117.

  12. Dating pleistocene fossil coastal sand dunes by thermoluminescence

    International Nuclear Information System (INIS)

    Poupeau, G.; Souza, J.H.; Soliani Junior, E.; Loss, E.L.

    1983-01-01

    It was shown recently that sunlight exposure is able to bleach most of the geological thermoluminescence (TL) of wind transported sediments. This property has been used in an attempt to date dunes from the well developed recent quaternary coastal dunes system of Rio Grande do Sul. Preliminary results presented here, show that TL dating on fossil sand dunes from Rio Grande do Sul should be possible in a time range from present to at least 50.000 yr and possibly more than 100.000 yr. (Author) [pt

  13. Erosion of Coastal Foredunes: A Review on the Effect of Dune Vegetation

    Science.gov (United States)

    2017-02-01

    inhabited by vegetation (Figure 2).The collision regime occurs when the total storm water level exceeds the elevation of the dune toe but is lower than the...of Dune Vegetation by Duncan B. Bryant, Mary A. Bryant, and Alison S. Grzegorzewski PURPOSE: The purpose of this Coastal and Hydraulics...Engineering Technical Note (CHETN) is to identify the potential roles of vegetation in mitigating coastal dune erosion during storm events by presenting a

  14. Dune management challenges on developed coasts

    Science.gov (United States)

    Elko, Nicole A.; Brodie, Kate; Stockdon, Hilary F.; Nordstrom, Karl F.; Houser, Chris; McKenna, Kim; Moore, Laura; Rosati, Julie D.; Ruggiero, Peter; Thuman, Roberta; Walker, Ian J.

    2015-01-01

    From October 26-28, 2015, nearly 100 members of the coastal management and research communities met in Kitty Hawk, NC, USA to bridge the apparent gap between the coastal dune research of scientists and engineers and the needs of coastal management practitioners. The workshop aimed to identify the challenges involved in building and managing dunes on developed coasts, assess the extent to which scientific knowledge can be applied to the management community, and identify approaches to provide means to bridge the gap between needs and potential solutions.

  15. The role of the reef–dune system in coastal protection in Puerto Morelos (Mexico

    Directory of Open Access Journals (Sweden)

    G. L. Franklin

    2018-04-01

    Full Text Available Reefs and sand dunes are critical morphological features providing natural coastal protection. Reefs dissipate around 90 % of the incident wave energy through wave breaking, whereas sand dunes provide the final natural barrier against coastal flooding. The storm impact on coastal areas with these features depends on the relative elevation of the extreme water levels with respect to the sand dune morphology. However, despite the importance of barrier reefs and dunes in coastal protection, poor management practices have degraded these ecosystems, increasing their vulnerability to coastal flooding. The present study aims to theoretically investigate the role of the reef–dune system in coastal protection under current climatic conditions at Puerto Morelos, located in the Mexican Caribbean Sea, using a widely validated nonlinear non-hydrostatic numerical model (SWASH. Wave hindcast information, tidal level, and a measured beach profile of the reef–dune system in Puerto Morelos are employed to estimate extreme runup and the storm impact scale for current and theoretical scenarios. The numerical results show the importance of including the storm surge when predicting extreme water levels and also show that ecosystem degradation has important implications for coastal protection against storms with return periods of less than 10 years. The latter highlights the importance of conservation of the system as a mitigation measure to decrease coastal vulnerability and infrastructure losses in coastal areas in the short to medium term. Furthermore, the results are used to evaluate the applicability of runup parameterisations for beaches to reef environments. Numerical analysis of runup dynamics suggests that runup parameterisations for reef environments can be improved by including the fore reef slope. Therefore, future research to develop runup parameterisations incorporating reef geometry features (e.g. reef crest elevation, reef lagoon width, fore

  16. The role of the reef-dune system in coastal protection in Puerto Morelos (Mexico)

    Science.gov (United States)

    Franklin, Gemma L.; Torres-Freyermuth, Alec; Medellin, Gabriela; Allende-Arandia, María Eugenia; Appendini, Christian M.

    2018-04-01

    Reefs and sand dunes are critical morphological features providing natural coastal protection. Reefs dissipate around 90 % of the incident wave energy through wave breaking, whereas sand dunes provide the final natural barrier against coastal flooding. The storm impact on coastal areas with these features depends on the relative elevation of the extreme water levels with respect to the sand dune morphology. However, despite the importance of barrier reefs and dunes in coastal protection, poor management practices have degraded these ecosystems, increasing their vulnerability to coastal flooding. The present study aims to theoretically investigate the role of the reef-dune system in coastal protection under current climatic conditions at Puerto Morelos, located in the Mexican Caribbean Sea, using a widely validated nonlinear non-hydrostatic numerical model (SWASH). Wave hindcast information, tidal level, and a measured beach profile of the reef-dune system in Puerto Morelos are employed to estimate extreme runup and the storm impact scale for current and theoretical scenarios. The numerical results show the importance of including the storm surge when predicting extreme water levels and also show that ecosystem degradation has important implications for coastal protection against storms with return periods of less than 10 years. The latter highlights the importance of conservation of the system as a mitigation measure to decrease coastal vulnerability and infrastructure losses in coastal areas in the short to medium term. Furthermore, the results are used to evaluate the applicability of runup parameterisations for beaches to reef environments. Numerical analysis of runup dynamics suggests that runup parameterisations for reef environments can be improved by including the fore reef slope. Therefore, future research to develop runup parameterisations incorporating reef geometry features (e.g. reef crest elevation, reef lagoon width, fore reef slope) is warranted.

  17. Natural and anthropogenic factors affecting freshwater lenses in coastal dunes of the Adriatic coast

    Science.gov (United States)

    Cozzolino, Davide; Greggio, Nicolas; Antonellini, Marco; Giambastiani, Beatrice Maria Sole

    2017-08-01

    This study characterizes the near-shore portion of the shallow coastal aquifer included in the Ravenna area (Northern Italy) with special attention to the roles of coastal dunes as freshwater reservoirs and their buffer on groundwater salinity. The paper focuses on the presence and evolution of freshwater lenses below coastal dunes and highlights the existing differences between preserved natural dunes and dunes strongly affected by human intervention. The influence that multiple natural and anthropogenic factors, such as land cover, local drainage network, and beach erosion have on the presence, size and evolution of the freshwater lenses in the aquifer is quantified and discussed. The methodology includes multiple seasonal monitoring and sampling campaigns of physical (water level, salinity, and temperature) and chemical (major cations and anions) groundwater parameters. Results indicate that freshwater lenses, where existing, are limited in thickness (about 1-2 m). Proximity to drainage ditches as well as limited dune elevation and size do not allow the formation and permanent storage of large freshwater lenses in the aquifer below the dunes. The pine forest land cover, that replaced the typical bush or sand cover, intensifies evapotranspiration reducing net infiltration and freshwater storage. The cation species distribution in the water shows that a freshening process is ongoing in preserved natural sites with stable or advancing beaches, whereas a salinization process is ongoing in anthropogenic-impacted areas with strongly-fragmented dune systems. Currently, the thin freshwater lenses in the shallow Ravenna coastal aquifer are limited in space and have no relevance for irrigation or any other human activity. The dune-beach system, however, is the recharge zone of the coastal aquifer and its protection is important to reduce water and soil salinization, which in turn control the health of the whole coastal ecosystem.

  18. Mediterranean coastal dune vegetation: Are disturbance and stress the key selective forces that drive the psammophilous succession?

    Science.gov (United States)

    Ciccarelli, Daniela

    2015-11-01

    Plant communities of coastal dunes are distributed along a characteristic sea-inland gradient. Generally, there is a shift from annual and short height species with small leaves in the initial successional stages to perennial tall shrubs with tough leaves in later phases. Assessing the community-weighted mean (CWM) trait values is used in plant ecology to describe ecosystem properties especially during succession. In particular, CSR (Competitive, Stress-tolerant, and Ruderal strategy) classification allows us to explore community functional shifts in terms of disturbance, stress and competition selective forces. The functional basis of the psammophilous succession was studied based on the following questions: (1) Can we circumscribe different functional types among plant species of Mediterranean coastal dunes? (2) How do CWM trait values vary along the environmental sea-inland gradient? (3) What is the relative importance of competition, stress and disturbance in the processes of plant community assembling? (4) Can we postulate that along primary successions there is generally a shift from ruderality to stress-tolerance? An explorative analysis of functional groups was performed by Non-Metric Multidimensional Scaling (NMDS) analysing nine morpho-functional traits measured for 45 taxa from 880 dune plots localised in Tuscany (central Italy, Europe). NMDS ordination showed a scattered distribution of psammophytes that could not be delimited in precise plant functional types. The first NMDS axis has been interpreted as a leaf economics axis because it was correlated to leaf area (LA) and leaf dry matter content (LDMC), while the second one was a plant size axis because of its correlation with canopy height. Along the sea-inland gradient, pioneer plant communities of upper beach were dominated by ruderals (with the lowest values of LDMC and specific leaf area - SLA), well-adapted to the harsh environmental conditions of coastal dunes. More distant from the sea, where

  19. The fate of threatened coastal dune habitats in Italy under climate change scenarios.

    Science.gov (United States)

    Prisco, Irene; Carboni, Marta; Acosta, Alicia T R

    2013-01-01

    Coastal dunes worldwide harbor threatened habitats characterized by high diversity in terms of plant communities. In Italy, recent assessments have highlighted the insufficient state of conservation of these habitats as defined by the EU Habitats Directive. The effects of predicted climate change could have dramatic consequences for coastal environments in the near future. An assessment of the efficacy of protection measures under climate change is thus a priority. Here, we have developed environmental envelope models for the most widespread dune habitats in Italy, following two complementary approaches: an "indirect" plant-species-based one and a simple "direct" one. We analyzed how habitats distribution will be altered under the effects of two climate change scenarios and evaluated if the current Italian network of protected areas will be effective in the future after distribution shifts. While modeling dune habitats with the "direct" approach was unsatisfactory, "indirect" models had a good predictive performance, highlighting the importance of using species' responses to climate change for modeling these habitats. The results showed that habitats closer to the sea may even increase their geographical distribution in the near future. The transition dune habitat is projected to remain stable, although mobile and fixed dune habitats are projected to lose most of their actual geographical distribution, the latter being more sensitive to climate change effects. Gap analysis highlighted that the habitats' distribution is currently adequately covered by protected areas, achieving the conservation target. However, according to predictions, protection level for mobile and fixed dune habitats is predicted to drop drastically under the climate change scenarios which we examined. Our results provide useful insights for setting management priorities and better addressing conservation efforts to preserve these threatened habitats in future.

  20. The impact of fire on sand dune stability: Surface coverage and biomass recovery after fires on Western Australian coastal dune systems from 1988 to 2016

    Science.gov (United States)

    Shumack, Samuel; Hesse, Paul; Turner, Liam

    2017-12-01

    This study aims to determine the common response of coastal sand dunes in Western Australia (WA) to fire on decadal time-scales, in terms of ecological-geomorphic-climatic interactions to test the hypothesis that fire plays a role in coastal dune destabilisation. Fires are commonly suggested to have contributed to widespread dune reactivation in Australia and globally, a hypothesis that is relatively untested. We used data from the Landsat Thematic Mapper, Enhanced Thematic Mapper Plus, and Operational Land Imager missions to monitor changes in surface coverage on coastal sand dunes in south-west WA after fires. We analysed 31 fire scars from 1988 to 2016 in two Landsat scenes on the west and south coast of WA. Recovery ratios derived from the Normalised Difference Vegetation Index (NDVI) were used to monitor patterns in post-fire biomass and surface cover. Recovery ratios are correlated with indices of burn severity, and meteorological data to investigate relationships. We also used Maximum Likelihood Classification to monitor changes in bare sand area. Results suggest that recovery followed a strongly consistent pattern, and is characterised by rapid vegetation cover re-establishment within six to twelve months. Prior to this, some aeolian activity may have occurred but without substantial surface changes. Initial germination and/or resprouting were followed by steady growth up to seven years, where NDVI typically neared pre-fire values. Some variation in early recovery occurred between the west and south coast, possibly owing to relative proportions of reseeding and resprouting plants. A log regression explained 75% of the recovery pattern (79% on the south coast). Precipitation had some ability to explain recovery up to nine months post-fire (r2 = 0.29 to 0.54). No relationships were observed between estimates of burn severity and recovery. After nine months, the biggest cause of spatial variation in recovery was the pre-fire community composition and related

  1. A native species with invasive behaviour in coastal dunes: evidence for progressing decay and homogenization of habitat types

    DEFF Research Database (Denmark)

    Nielsen, Knud Erik; Degn, Hans Jørgen; Damgaard, Christian

    2011-01-01

    A new species has recently invaded coastal dune ecosystems in North West Europe. The native and expansive inland grass, Deschampsia flexuosa, progressively dominating inland heaths, has recently invaded coastal dunes in Denmark, occasionally even as a dominant species. A total of 222 coastal loca...

  2. RIGED-RA project - Restoration and management of Coastal Dunes in the Northern Adriatic Coast, Ravenna Area - Italy

    Science.gov (United States)

    Giambastiani, Beatrice M. S.; Greggio, Nicolas; Sistilli, Flavia; Fabbri, Stefano; Scarelli, Frederico; Candiago, Sebastian; Anfossi, Giulia; Lipparini, Carlo A.; Cantelli, Luigi; Antonellini, Marco; Gabbianelli, Giovanni

    2016-10-01

    Coastal dunes play an important role in protecting the coastline. Unfortunately, in the last decades dunes have been removed or damaged by human activities. In the Emilia- Romagna region significant residual dune systems are found only along Ravenna and Ferrara coasts. In this context, the RIGED-RA project “Restoration and management of coastal dunes along the Ravenna coast” (2013-2016) has been launched with the aims to identify dynamics, erosion and vulnerability of Northern Adriatic coast and associated residual dunes, and to define intervention strategies for dune protection and restoration. The methodology is based on a multidisciplinary approach that integrates the expertise of several researchers and investigates all aspects (biotic and abiotic), which drive the dune-beach system. All datasets were integrated to identify test sites for applying dune restoration. The intervention finished in April 2016; evolution and restoration efficiency will be assessed.

  3. How to integrate geology, biology, and modern wireless technologies to assess biotic-abiotic interactions on coastal dune systems: a new multidisciplinary approach

    Science.gov (United States)

    Sarti, Giovanni; Bertoni, Duccio; Bini, Monica; Ciccarelli, Daniela; Ribolini, Adriano; Ruocco, Matteo; Pozzebon, Alessandro; Alquini, Fernanda; Giaccari, Riccardo; Tordella, Stefano

    2014-05-01

    Coastal dune systems are arguably one of the most dynamic environments because their evolution is controlled by many factors, both natural and human-related. Hence, they are often exposed to processes leading to erosion, which in turn determine serious naturalistic and economic losses. Most recent studies carried out on different dune fields worldwide emphasized the notion that a better definition of this environment needs an approach that systematically involves several disciplines, striving to merge every data collected from any individual analyses. Therefore, a new multidisciplinary method to study coastal dune systems has been conceived in order to integrate geology, biology, and modern wireless technologies. The aim of the work is threefold: i) to check the reliability of this new approach; ii) to provide a dataset as complete as ever about the factors affecting the evolution of coastal dunes; and iii) to evaluate the influence of any biotic and abiotic factors on plant communities. The experimentation site is located along the Pisa coast within the Migliarino - S. Rossore - Massaciuccoli Regional Park, a protected area where human influence is low (Tuscany, Italy). A rectangle of 100 x 200 m containing 50 grids of 20 x 20 m was established along the coastal dune systems from the coastline to the pinewood at the landward end of the backdune area. Sampling from each grid determined grain-size analysis carried out on surface sediment samples such as geologic aspects; topographic surveys performed by means of DGPS-RTK instruments; geophysical surveys conducted with a GPR equipment, which will be matched with core drilling activities; digital image analysis of high definition pictures taken by means of a remote controlled aircraft drone flying over the study area; biological data obtained by percent cover of each vascular plant species recorded in the sampling unit. Along with geologic and biologic methodologies, this research implemented the use of informatics

  4. Mineralogy and Genesis of Heavy Minerals in Coastal Dune Sands, South Eastern Qatar

    OpenAIRE

    Nasir, Sobhi J. [صبحي جابر نصر; El-Kassas, Ibrahim A.; Sadiq, A. Ali M.

    1999-01-01

    Large amounts of aeolian sand occur in the southeastern coastal zone of Qatar Peninsula as sand dunes accumulated in a vast sand field locally called " Niqyan Qatar ". The present work, carried out on a sand dune belt of this field near Mesaied Industrial City, revealed the distribution of heavy minerals shows a regional variability induced by provenance and local variability reflecting genetic differences. The studied dune sands are rich in shells of pelecypods, with the light mineral assemb...

  5. Characterization and Ecophysiological Observations on Coastal Sand Dune Vegetation from Goa, Central West Coast, India

    Digital Repository Service at National Institute of Oceanography (India)

    Rodrigues, R.S.

    Coastal Sand Dune flora (CSD) forms a specialized group of plants commonly referred as psammophytes. Goa has limited natural resources including beaches and sand dunes. The state is globally known for its tourism activities, which pressurize...

  6. Nutrient limitation and vegetation changes in a coastal dune slack

    NARCIS (Netherlands)

    Lammerts, EJ; Pegtel, DM; Grootjans, AP; van der Veen, A.

    Basiphilous pioneer species are among the most endangered plant species in The Netherlands. They find most of their refuges in young coastal dune slacks, especially on the Wadden Sea islands. For the purpose of nature management it is important to know which processes control the presence of

  7. UAV-imaging to model growth response of marram grass to sand burial: Implications for coastal dune development

    Science.gov (United States)

    Nolet, Corjan; van Puijenbroek, Marinka; Suomalainen, Juha; Limpens, Juul; Riksen, Michel

    2018-04-01

    Vegetated coastal dunes have the capacity to keep up with sea-level rise by accumulating and stabilizing wind-blown sand. In Europe, this is attributed to marram grass (Ammophila arenaria), a coastal grass species that combines two unique advantages for dune-building: (1) a very high tolerance to burial by wind-blown sand, and (2) more vigorous growth due to positive feedback to sand burial. However, while these vegetation characteristics have been demonstrated, observational data has not been used to model a function to describe the growth response of Ammophila to sand burial. Studies that model coastal dune development by incorporating positive feedback, as a result, may be hampered by growth functions that are unvalidated against field data. Therefore, this study aims to parameterize an empirical relationship to model the growth response of Ammophila to burial by wind-blown sand. A coastal foredune along a nourished beach in the Netherlands was monitored from April 2015 to April 2016. High-resolution geospatial data was acquired using an Unmanned Aerial Vehicle (UAV). Growth response of Ammophila, expressed by changes in Normalized Difference Vegetation Index (Δ NDVI) and vegetation cover (Δ Cover), is related to a sand burial gradient by fitting a Gaussian function using nonlinear quantile regression. The regression curves indicate an optimal burial rate for Ammophila of 0.31 m of sand per growing season, and suggest (by extrapolation of the data) a maximum burial tolerance for Ammophila between 0.78 (for Δ Cover) and 0.96 m (for Δ NDVI) of sand per growing season. These findings are advantageous to coastal management: maximizing the potential of Ammophila to develop dunes maximizes the potential of coastal dunes to provide coastal safety.

  8. Invasive plants on disturbed Korean sand dunes

    Science.gov (United States)

    Kim, Kee Dae

    2005-01-01

    The sand dunes in coastal regions of South Korea are important ecosystems because of their small size, the rare species found in this habitat, and the beautiful landscapes they create. This study investigated the current vegetative status of sand dunes on three representative coasts of the Korean peninsula, and on the coasts of Cheju Island, and assessed the conditions caused by invasive plants. The relationships between the degree of invasion and 14 environmental variables were studied. Plots of sand dunes along line transects perpendicular to the coastal lines were established to estimate vegetative species coverage. TWINSPAN (Two-Way Indicator Species Analysis), CCA (Canonical Correspondence Analysis), and DCCA (Detrended Canonical Correspondence Analysis) were performed to classify communities on sand dunes and assess species composition variation. Carex kobomugi, Elymus mollis, and Vitex rotundifolia were found to be the dominant species plotted on the east, the west, and the peripheral coasts of Cheju Island, respectively. Vegetation on the south coast was totally extinct. The 19 communities, including representative C. kobomugi, C. kobomugi- Ixeris repens, C. kobomugi- Oenothera biennis, E. mollis, Lolium multiflorum- Calystegia soldanella, and V. rotundifolia- C. kobomugi, were all classified according to TWINSPAN. Oenothera biennis and L. multiflorum were exotics observed within these native communities. CCA showed that invasive native and exotic species distribution was segregated significantly, according to disturbance level, exotic species number, gravel, sand and silt contents, as well as vegetation size. It further revealed that human disturbance can strongly favor the settlement of invasive and exotic species. Restoration options to reduce exotic plants in the South Korean sand dune areas were found to be the introduction of native plant species from one sand dune into other sand dune areas, prohibition of building and the introduction of exotic

  9. Conservation of Sand Dune Vegetation in Coastal areas of the Valencian Region (Spain); Estado de conservacion de la vegetacion dunar en las costas de la comunidad Valenciana

    Energy Technology Data Exchange (ETDEWEB)

    Albertos, B.; San Miguel, E.; Draper, I.; Garilleti, R.; Lara, F.; Varela, J. M.

    2010-07-01

    The state of conservation of the coastal dune vegetation in Valencia region has been assessed within a survey of the vegetal communities present in these systems.The conservation status has been evaluated through a qualitative scale which integrates criteria such as dune extension, structure and diversity of the vegetal communities, level of ruderalization, presence of invasive species, and floristic rarity. Special attention has been paid to the usual aggressions to this type of ecosystem and the situation of the most aggressive invasive plants. (Author) 15 refs.

  10. Effects of disturbance on vegetation by sand accretion and erosion across coastal dune habitats on a barrier island.

    Science.gov (United States)

    Miller, Thomas E

    2015-01-12

    Coastal geomorphology and vegetation are expected to be particularly sensitive to climate change, because of disturbances caused by sea-level rise and increased storm frequency. Dunes have critical reciprocal interactions with vegetation; dunes create habitats for plants, while plants help to build dunes and promote geomorphological stability. These interactions are also greatly affected by disturbances associated with sand movement, either in accretion (dune building) or in erosion. The magnitude and intensity of disturbances are expected to vary with habitat, from the more exposed and less stable foredunes, to low-lying and flood-prone interdunes, to the protected and older backdunes. Permanent plots were established at three different spatial scales on St George Island, FL, USA, where the vegetation and dune elevation were quantified annually from 2011 to 2013. Change in elevation, either through accretion or erosion, was used as a measure of year-to-year disturbance over the 2 years of the study. At the scale of different dune habitats, foredunes were found to have the greatest disturbance, while interdunes had the least. Elevation and habitat (i.e. foredune, interdune, backdune) were significantly correlated with plant community composition. Generalized linear models conducted within each habitat show that the change in elevation (disturbance) is also significantly correlated with the plant community, but only within foredunes and interdunes. The importance of disturbance in exposed foredunes was expected and was found to be related to an increasing abundance of a dominant species (Uniola paniculata) in eroding areas. The significant effect of disturbance in the relatively stable interdunes was surprising, and may be due to the importance of flooding associated with small changes in elevation in these low-lying areas. Overall, this study documents changes in the plant community associated with elevation, and demonstrates that the foredune and interdune

  11. 44 CFR 65.11 - Evaluation of sand dunes in mapping coastal flood hazard areas.

    Science.gov (United States)

    2010-10-01

    ... mapping coastal flood hazard areas. 65.11 Section 65.11 Emergency Management and Assistance FEDERAL... Insurance Program IDENTIFICATION AND MAPPING OF SPECIAL HAZARD AREAS § 65.11 Evaluation of sand dunes in mapping coastal flood hazard areas. (a) General conditions. For purposes of the NFIP, FEMA will consider...

  12. The Mediterranean Coastal Dunes in Egypt: An Endangered Landscape

    Science.gov (United States)

    Batanouny, K. H.

    1999-08-01

    The Mediterranean coast in Egypt extends almost 900 km, the major part of which is bordered by sand dunes of different natures and types. Along the coastline between Alexandria and El-Alamein, a distance of some 100 km, the sand dunes represent a particular landscape with special characteristics and features, and consequently plants with particular attributes. In this area, the belt of sand dunes has developed immediately south of the shore and these dunes may rise up to 10 m in height and extend about 0·5-1·5 km inland from the shore. These dunes are famous as a habitat for the fig (Ficus carica L.) cultivation depending on the irregular rainfall. They also represent a landing station and a cross-road for birds such as quail migrating from Europe in the north. In the past, summer resort areas were confined to limited areas with few people, these same areas support the growth of some important plant species, for example, sand binders, medicinal and range plants. For more than two decades, there has been considerable socio-economic change and an open-door policy in the economy of the country has been adopted. One of the consequences of this change is that a great part of the coastal dune belt west of Alexandria till El-Alamein, has been subjected to destruction, due to the continuous construction of summer resort villages. These were built at a distance of about 100 m of the shoreline, extending 400-600 m inland and a breadth of 400 m or more along the shoreline. The area already covered by the dunes is now almost occupied by new buildings, gardens and other infrastructure. The consequences of these human activities are numerous and include impacts on the soil, water resources, the flora and the fauna, migrating birds, trends of the indigenous people, and the cultural environment. The present paper gives a concise environmental setting of the dune belt before the advent of the new activities, and the socio-economic and political attitudes which threaten the dunes

  13. Late Pleistocene dune-sourced alluvial fans in coastal settings: Sedimentary facies and related processes (Mallorca, Western Mediterranean)

    Science.gov (United States)

    Pomar, F.; del Valle, L.; Fornós, J. J.; Gómez-Pujol, L.

    2018-05-01

    Aeolian-alluvial sedimentary interaction results in the formation of deposits characterized by typical alluvial sedimentary structures, but is composed of conspicuous amounts of aeolian sediments. The literature on this topic is limited and most works relate more with continental aeolian dunes or fluvial dune interference with fan bodies. Furthermore, there is a lack of examples of aeolian-alluvial sedimentary interference in coastal settings. In the western Mediterranean, there are many Pleistocene alluvial fan deposits built up partly by sediment originating from coastal dunes dismantled by alluvial streams. Very often, these deposits show a continuous sedimentary sequence through which we can derive the contribution and predominance of coastal, alluvial-colluvial and aeolian processes and their controls on landscape formation. This is an outstanding feature within coastal systems since it shows marine sediments reworked and integrated within coastal dune fields by aeolian transport, and the latter built up into alluvial fan bodies. In this sense, aeolian-alluvial interaction is the geomorphic-sedimentary expression of the coexistence and overlapping of alluvial and aeolian environments resulting in deposits sharing sedimentary features from both environments. The aim of this paper is to unravel the contribution of coastal dunes in the construction of alluvial fans bodies and identify the main sedimentary facies that constitute these deposits, as well as their climatic controls. For this reason, Es Caló fan (northern Mallorca) has been selected due to its well-exposed deposits exhibiting the alternation of aeolian, alluvial and colluvial deposits. Sedimentological and stratigraphic analyses based on 33 logs and complementary analyses demonstrate that most of the facies constituting the fan body are made up completely of marine bioclastic sands. These deposits record an alluvial fan sedimentary environment characterized by sediments inputs that do not proceed

  14. Changes in vegetation and biological soil crust communities on sand dunes stabilizing after a century of grazing on San Miguel Island, Channel Island National Park, California

    Science.gov (United States)

    Zellman, Kristine L.

    2014-01-01

    San Miguel Island is the westernmost of the California Channel Islands and one of the windiest areas on the west coast of North America. The majority of the island is covered by coastal sand dunes, which were stripped of vegetation and subsequently mobilized due to droughts and sheep ranching during the late 19th century and early 20th century. Since the removal of grazing animals, vegetation and biological soil crusts have once again stabilized many of the island's dunes. In this study, historical aerial photographs and field surveys were used to develop a chronosequence of the pattern of change in vegetation communities and biological soil crust levels of development (LOD) along a gradient of dune stabilization. Historical aerial photographs from 1929, 1954, 1977, and 2009 were georeferenced and used to delineate changes in vegetation canopy cover and active (unvegetated) dune extent among 5 historical periods (pre-1929, 1929–1954, 1954–1977, 1977–2009, and 2009–2011). During fieldwork, vegetation and biological soil crust communities were mapped along transects distributed throughout San Miguel Island's central dune field on land forms that had stabilized during the 5 time periods of interest. Analyses in a geographic information system (GIS) quantified the pattern of changes that vegetation and biological soil crust communities have exhibited on the San Miguel Island dunes over the past 80 years. Results revealed that a continuing increase in total vegetation cover and a complex pattern of change in vegetation communities have taken place on the San Miguel Island dunes since the removal of grazing animals. The highly specialized native vascular vegetation (sea rocket, dunedelion, beach-bur, and locoweed) are the pioneer stabilizers of the dunes. This pioneer community is replaced in later stages by communities that are dominated by native shrubs (coastal goldenbush, silver lupine, coyote-brush, and giant coreopsis), with apparently overlapping or

  15. Even low to medium nitrogen deposition impacts vegetation of dry, coastal dunes around the Baltic Sea

    NARCIS (Netherlands)

    Remke, E.; Brouwer, E.; Kooijman, A.; Blindow, I.; Esselink, H.; Roelofs, J.G.M.

    2009-01-01

    Coastal dunes around the Baltic Sea have received small amounts of atmospheric nitrogen and are rather pristine ecosystems in this respect. In 19 investigated dune sites the atmospheric wet nitrogen deposition is 3-8 kg N ha−1 yr−1. The nitrogen content of Cladonia portentosa appeared to be a

  16. Application of the ERICA Integrated Approach to the Drigg coastal sand dunes

    International Nuclear Information System (INIS)

    Wood, M.D.; Marshall, W.A.; Beresford, N.A.; Jones, S.R.; Howard, B.J.; Copplestone, D.; Leah, R.T.

    2008-01-01

    The EC-funded project 'Environmental Risks from Ionising Contaminants: Assessment and Management' (ERICA) developed an 'Integrated Approach' for assessing the impact of ionising radiation on ecosystems. This paper presents the application of the ERICA Integrated Approach, supported by a software programme (the ERICA Tool) and guidance documentation, to an assessment of the Drigg coastal sand dunes (Cumbria, UK). Targeted sampling provided site-specific data for sand dune biota, including amphibians and reptiles. Radionuclides reported included 90 Sr, 99 Tc, 137 Cs, 238 Pu, 239+240 Pu and 241 Am. Site-specific data were compared to predictions derived using the ERICA Tool. Some under- and over-predictions of biota activity concentrations were identified but can be explained by the specific ecological characteristics and contamination mechanism of the dunes. Overall, the results indicated no significant impact of ionising radiation on the sand dune biota and the Integrated Approach was found to be a flexible and effective means of conducting a radiation impact assessment

  17. Vegetative and reproductive phenological patterns in coastal dunes in S Spain

    Directory of Open Access Journals (Sweden)

    Rodríguez-Gallego, Carmen

    2015-06-01

    Full Text Available The phenology of Mediterranean plant species has been extensively studied in different types of ecosystems. However, very little research has been conducted on dune ecosystems. The aim of this research is the phenological characterization and comparison among phenological patterns in three coastal dunes areas in S Spain. For this purpose, we apply the methodology proposed by Orshan (1989 and NLPCA phenological indexes. Our results show that seasonality of species from coastal dunes in S Spain follows the pattern observed in dry and warm Mediterranean ecosystems. The maximum phenological activity occurs for a period of 7-9 months, mainly in spring and late winter, whereas summer is clearly the most inactive period of the year. Vegetative phenophases predominate over the reproductive. Flowering is mainly early (March-May, but it may extend to summer. Flowering duration has been identified as a key index in the differentiation among coastal dunes with different conditions of Mediterranean macroclimate, whereas the importance of the phenophase sequence index has been shown in order to discriminate sectors within dunes. Using the NLPCA analysis based on phenological indexes, four phenological groups of species have been determined. From a conservation perspective, the identification of these groups point out the utility of developing different strategies of management according to the high diversity of eco- and phenomorphological variability that characterize the coastal dunes.La fenología de las especies vegetales mediterráneas ha sido ampliamente estudiada en diferentes tipos de ecosistemas. Sin embargo, es poco lo que se conoce sobre fenología de dunas costeras. El objetivo del presente trabajo es la caracterización y comparación de patrones fenológicos en tres áreas de dunas costeras del Sur de España. Para ello, se ha aplicado la metodología propuesta por Orshan (1989 así como índices fenológicos NLPCA. Nuestros resultados muestran

  18. Coastal dunes of South Africa

    CSIR Research Space (South Africa)

    Tinley, KL

    1985-01-01

    Full Text Available . The descriptive section is divided into geographic setting, physical features, ecological features and dune dynamics. Emphasis is placed on the factors affecting dune formation and erosion and the biogeography and dynamics of dune vegetation. Current use...

  19. Occupancy dynamics of wild rabits (Oryctolagus cuniculus) in the coastal dunes of the Nederlands with imperfect detection

    NARCIS (Netherlands)

    Strien, van A.J.; Dekker, J.J.A.; Straver, M.; Meij, van der T.; Soldaat, L.L.; Ehrenburg, A.; Loon, van E.

    2011-01-01

    Context: Wild rabbits are considered a key species in the coastal dunes of the Netherlands, but populations have collapsed as a result of viral diseases. Aim: We studied to what extent population collapse led to local extinction and whether recolonisation of empty patches in the dunes happened.

  20. Occupancy dynamics of wild rabbits (Oryctolagus cuniculus) in the coastal dunes of the Netherlands with imperfect detection

    NARCIS (Netherlands)

    van Strien, A.J.; Dekker, J.J.A.; Straver, M.; van der Meij, T.; Soldaat, L.L.; Ehrenburg, A.; van Loon, E.

    2011-01-01

    Context: Wild rabbits are considered a key species in the coastal dunes of the Netherlands, but populations have collapsed as a result of viral diseases. Aim: We studied to what extent population collapse led to local extinction and whether recolonisation of empty patches in the dunes happened.

  1. Even low to medium nitrogen deposition impacts vegetation of dry, coastal dunes around the Baltic Sea

    International Nuclear Information System (INIS)

    Remke, Eva; Brouwer, Emiel; Kooijman, Annemieke; Blindow, Irmgard; Esselink, Hans; Roelofs, Jan G.M.

    2009-01-01

    Coastal dunes around the Baltic Sea have received small amounts of atmospheric nitrogen and are rather pristine ecosystems in this respect. In 19 investigated dune sites the atmospheric wet nitrogen deposition is 3-8 kg N ha -1 yr -1 . The nitrogen content of Cladonia portentosa appeared to be a suitable biomonitor of these low to medium deposition levels. Comparison with EMEP-deposition data showed that Cladonia reflects the deposition history of the last 3-6 years. With increasing nitrogen load, we observed a shift from lichen-rich short grass vegetation towards species-poor vegetation dominated by the tall graminoid Carex arenaria. Plant species richness per field site, however, does not decrease directly with these low to medium N deposition loads, but with change in vegetation composition. Critical loads for acidic, dry coastal dunes might be lower than previously thought, in the range of 4-6 kg N ha -1 yr -1 wet deposition. - Even low to medium nitrogen deposition impacts Baltic dune vegetation promoting a dominance of taller graminoids

  2. Disturbance in dry coastal dunes in Denmark promotes diversity of plants and arthropods

    DEFF Research Database (Denmark)

    Brunbjerg, Ane Kirstine; Jørgensen, Gorm Pilgaard; Nielsen, Kristian Mandsberg

    2015-01-01

    of three disturbance types (burning, trampling and blowouts) on plant and arthropod species richness and composition in dry coastal dunes in Jutland, Denmark. Environmental variables, plant presence–absence and arthropod abundance were measured in 150 1 × 2 m plots along transects in blowouts, burned areas...... on plant and arthropod composition. Indicator species analysis revealed plant and arthropod species indicative for different disturbances. Plant and arthropod species richness and the number of annual plant species generally increased with disturbance, and plant and arthropod richness and composition...... responded differently to different disturbances. Arthropod communities were more diverse in disturbed plots and hosted species often found in early successional habitats of potential conservation value. Disturbance promoted β-diversity, but affected plants more than arthropods, likely because...

  3. Understanding the hydrochemical evolution of a coastal dune system in SW England using a multiple tracer technique

    International Nuclear Information System (INIS)

    Allen, Debbie; Darling, W. George; Williams, Peter J.; Stratford, Charlie J.; Robins, Nick S.

    2014-01-01

    Highlights: • Braunton Burrows is an alkaline rain-fed system with no saline intrusion. • Marine aerosols and shell dissolution dominate unsaturated zone water quality. • Hydrochemical evolution in the unsaturated zone is rapid. • Slower evolutionary processes contribute to water quality in the saturated zone. • High dune groundwaters were 13–16 yr old and dune slack groundwater 5–7 yr old. - Abstract: An improved knowledge of the hydrology of coastal dune systems is desirable for successful management of their diverse ecology under a changing climate. As a near-pristine coastal dune spit system, Braunton Burrows (SW England) is an ideal location for the study of the natural processes governing recharge to the dune groundwater system and the evolution of its water quality. Whereas previous investigations have tended to focus on inter-dune slacks, this study has also given attention to infiltration through the high dunes. Cores were taken through dunes and the resulting sand samples processed to provide information on grain size distribution and porewater chemistry. Groundwater samples were obtained from beneath dunes and slacks. A variety of geochemical techniques were applied including hydrochemistry, stable isotopes and residence time indicators. The unsaturated zone profiles indicate the existence of piston flow recharge with an infiltration rate of 0.75–1 m/yr, although faster rates probably also occur locally. Groundwater beneath the high dunes gave ages in the range 13–16 yr, compared to the dune slack groundwater ages of 5–7 yr, and an age of 22 yr for groundwater from the underlying mudstone aquifer. The chemistry of waters in both unsaturated and saturated zones is dominated by Ca and HCO 3 , supplemented by variable amounts of other ions derived from marine aerosols and limited reaction with sand grains and their coatings. The main chemical evolution of the porewaters occurs rapidly through the mobilisation of surface salt crusts and

  4. Coastal dune dynamics in response to excavated foredune notches

    Science.gov (United States)

    Ruessink, B. G.; Arens, S. M.; Kuipers, M.; Donker, J. J. A.

    2018-04-01

    Dune management along developed coasts has traditionally focussed on the suppression of the geomorphic dynamics of the foredune to improve its role in sea defence. Because a stabilized foredune acts as an almost total barrier to aeolian transport from the beach, the habitat diversity in the more landward dunes has degraded. With the overarching objective to mitigate this undesirable loss in biodiversity, dune management projects nowadays increasingly intend to restore aeolian dynamics by reconnecting the beach-dune system with notches excavated through the foredune. Here, we use repeat topographic survey data to examine the geomorphic response of a coastal dune system in the Dutch National Park Zuid-Kennemerland to five notches excavated in 2012-2013 within an 850-m stretch of the 20-m high established foredune. The notches were dug in a V-shape (viewed onshore), with a width between approximately 50 and 100 m at the top, a (cross-dune) length between 100 and 200 m, and excavation depths between 9 and 12.5 m. The 1 × 1 m digital terrain models, acquired with airborne Lidar and UAV photogrammetry, illustrate that during the 3-year survey period the notches developed into a U-shape because of wall deflation, and that up to 8-m thick and 150-m long depositional lobes formed landward of the notches. Sand budget computations showed that the sand volume of the entire study area increased by about 22,750 m3/year, which, given the 850-m width of the study area, corresponds to an aeolian input from the beach of approximately 26.5 m3/m/year. Between 2006 and 2012 all wind-blown beach sand deposited on the seaward side of the foredune; since 2013, the notches have caused 75% of the sand to be deposited landward of the foredune. This highlights that the notches are highly effective conduits for aeolian transport into the back dunes. Future monitoring is required to determine for how long the notches will stimulate aeolian dynamics and if (and when) vegetation eventually

  5. Application of the ERICA Integrated Approach to the Drigg coastal sand dunes

    Energy Technology Data Exchange (ETDEWEB)

    Wood, M.D. [Institute for Sustainable Water Integrated Management and Ecosystem Research (SWIMMER)/School of Biological Sciences, Nicholson Building, University of Liverpool, Liverpool, Merseyside L69 3GP (United Kingdom)], E-mail: mwood@liv.ac.uk; Marshall, W.A. [Westlakes Scientific Consulting Ltd., Princess Royal Building, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3LN (United Kingdom); Beresford, N.A. [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster, Lancashire LA1 4AP (United Kingdom); Jones, S.R. [Westlakes Scientific Consulting Ltd., Princess Royal Building, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3LN (United Kingdom); Howard, B.J. [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster, Lancashire LA1 4AP (United Kingdom); Copplestone, D. [Environment Agency, P.O. Box 12, Richard Fairclough House, Knutsford Road, Latchford, Warrington, Cheshire WA4 1HG (United Kingdom); Leah, R.T. [Institute for Sustainable Water Integrated Management and Ecosystem Research (SWIMMER)/School of Biological Sciences, Nicholson Building, University of Liverpool, Liverpool, Merseyside L69 3GP (United Kingdom)

    2008-09-15

    The EC-funded project 'Environmental Risks from Ionising Contaminants: Assessment and Management' (ERICA) developed an 'Integrated Approach' for assessing the impact of ionising radiation on ecosystems. This paper presents the application of the ERICA Integrated Approach, supported by a software programme (the ERICA Tool) and guidance documentation, to an assessment of the Drigg coastal sand dunes (Cumbria, UK). Targeted sampling provided site-specific data for sand dune biota, including amphibians and reptiles. Radionuclides reported included {sup 90}Sr, {sup 99}Tc, {sup 137}Cs, {sup 238}Pu, {sup 239+240}Pu and {sup 241}Am. Site-specific data were compared to predictions derived using the ERICA Tool. Some under- and over-predictions of biota activity concentrations were identified but can be explained by the specific ecological characteristics and contamination mechanism of the dunes. Overall, the results indicated no significant impact of ionising radiation on the sand dune biota and the Integrated Approach was found to be a flexible and effective means of conducting a radiation impact assessment.

  6. Arbuscular mycorrhizal fungi associated with psammophilic vegetation in Mediterranean coastal sand dunes

    Energy Technology Data Exchange (ETDEWEB)

    Camprubi, A.; Calvet, C.; Cabot, P.; Pitet, M.; Estaun, V.

    2010-07-01

    This study was conducted in order to characterize the natural albacore's mycorrhizal (AM) biodiversity from Mediterranean sand dune ecosystems and to protect in a collection this biodiversity. The occurrence of AM fungi associated with sand dune plant species in three Mediterranean locations on the north-eastern coast of Spain was examined in one well preserved coastal sand dune and in two embrionary dunes recently protected from public access. Traditional taxonomy and molecular techniques were used to identify the AM fungal species present in these ecosystems. The species identified and isolated were: Scutellospora persica (Kiosk and Walker) Walker and Sanders, Glomus ambisporum Smith and Schenck, Glomus diaphanum Morton and Walker, Glomus clarum Nicolson and Schenck, Glomus intraradices Schenck and Smith, Glomus microaggregatum Koske, Gemma and Olexia and Gigaspora margarita Becker and Hall. Spores of Glomus were the most abundant in the direct soil extraction samples. The molecular analysis indicates that the most abundant fungi forming AM in the roots belonged to the Gigasporaceae group followed by fungi of Glomus group A and Glomus group B. The highest diversity of fungi and abundance of the AM fungal spores was found in the well preserved and undisturbed dune systems. (Author) 26 refs.

  7. Dynamic dune management, integrating objectives of nature development and coastal safety: Examples from the Netherlands

    Science.gov (United States)

    Arens, Sebastiaan M.; Mulder, Jan P. M.; Slings, Quirinus L.; Geelen, Luc H. W. T.; Damsma, Petra

    2013-10-01

    This paper discusses and compares results of management interventions to remobilise dunes and obtain more autonomous changes in foredunes resulting from a change in coastal defence policy. In recent decades, nature conservation managers tried to restore aeolian dynamics and dune mobility landward of foredunes to maintain threatened, rare pioneer species. Results indicate that destabilisation activities yielded an important increase of blowing sand and its effects on ecology but with a limited effect on the desired integral remobilization of dunes. Roots remaining in the sand after removal of vegetation and soil is one of the main problems. Follow up removal of roots for 3 to 5 years seems to be essential, but it is not clear whether the dunes will remain mobile in the long term. In 1990 the Dutch government decided to maintain the position of the coastline by artificial sand nourishment. An intensive management of the foredunes was no longer required. Consequently, natural processes in the foredunes revived, and the sediment budget of the beach-dune system changed. Two main types of responses are visible. In some areas, increased input of sand resulted in the development of embryonic dunes seaward of the former foredunes, leading to increased stabilisation of the former foredunes. In other areas, development of embryonic dunes was insignificant despite the increased sand input, but wind erosion features developed in the foredunes, and the environment was more dynamic. The reasons for the differences are not clear, and the interaction between shoreface, beach and dunes is still poorly understood. Until now, attempts to mobilise the inner dunes were independent of changes made to the foredunes. We argue that an integrated, dynamic approach to coastal management, taking account of all relevant functions (including safety and natural values) and the dune-beach system as a whole, may provide new and durable solutions. An integrated approach would ideally provide fresh

  8. Holocene coastal dune development and environmental changes in Helis area (NW Peloponnese, Greece

    Directory of Open Access Journals (Sweden)

    L. STAMATOPOULOS

    2017-12-01

    Full Text Available The coastal area of western Peloponnese is characterized by Pleistocene and Holocene marine deposits. The study area shows the effects of different phases of coastal morphology evolution and is located along a wave-dominated and microtidal coast in the northwestern Peloponnese, 40 km southwest of Patras city. Three significant morphogenetic phases occurred during the Holocene. The first was radiometrically aged from 7000 to 3810 years BP, marking the end of the rapid postglacial transgression. The second, between 3810 and 1400 years BP, was characterized by high rates of sedimentation, possibly because of the proximity of the mouth of the Peneus River, and resulted in the accumulation of predominantly fluvial sediments. During the third and younger phase, from 1400 years BP to the present, landward migration of the coast and deposition of aeolian sands occurred. Archaeological and morphological evidences suggest that this last phase should be related to a low sea-level stand followed by a slow sea-level rise, up to the present-day position and by humid-temperate climate. The collected data concerning the Holocene coastal dune belts, suggest that main phases of dune development could be related to the effects of sea-level changes, climatic conditions, and in a subordinate way, to human activity.

  9. Sensitivity Analysis of Dune Height Measurements Along Cross-shore Profiles Using a Novel Method for Dune Ridge Extraction

    Science.gov (United States)

    Hardin, E.; Mitasova, H.; Overton, M.

    2010-12-01

    In barrier islands where communities are subjected to hazards including storm surge and high wave height, coastal dunes offer the first line of defense to property and vital infrastructure. When dunes are over-washed, substantial damage, including complete destruction of buildings and roads can occur. For this reason, dunes are an integral aspect of coastal hazard management. As new, more efficient mapping and analysis technologies evolve, currently used methodologies should be regularly be reexamined in order to ensure the development of the most effective coastal management strategies. Currently, topographical parameters, such as dune height, are usually measured along evenly spaced, shore-perpendicular beach profiles. In previous studies, profile spacing has varied from 20m to over 500m, however, it has been shown that dune height can vary substantially over tens of meters. Profile spacing is a compromise between the resources needed to perform high-resolution measurements and ensuring the capture of meaningful dune features. While it is often clear how the choice of profile spacing will affect the resources needed to perform the analysis, it is often unclear how spacing affects the ability to capture significant dune variation and prevent omission of a narrow dune breach that can open the way for significant flooding. In this study, the structure of alongshore variation in dune height is investigated. The studied dune ridge is located in the Outer Banks, North Carolina, USA and stretches 18km from south of Oregon Inlet (75:31:19W, 35:46:03N) to Rodanthe (75:27:56W, 35:36:31N). The dune ridge is extracted from a 0.5m resolution Digital Elevation Model (DEM) that was interpolated from airborne lidar data using regularized spline with tension. The lidar data was collected in March 2008 by the National Oceanic and Atmospheric Administration. A dune ridge is usually identified as the highest elevation along a shore-perpendicular profile or where ocean-facing slope

  10. Coastal sand dune ecosystem services in metropolitan suburbs: effects on the sake brewery environment induced by changing social conditions

    Science.gov (United States)

    Kaneko, Korehisa; Matsushima, Hajime

    2017-12-01

    Chiba Prefecture, Japan, lies very near Tokyo, the capital city of Japan. It borders the sea on three sides and is banded by coastal dunes. Several sake breweries are located near these dunes. Although there are records of sake brewing along the coast of Tokyo Bay since 1925, sake breweries have completely disappeared in several areas. We believe that sake brewing in these areas benefited from the ecosystem services afforded them by their proximity to the coastal ecosystem. We investigated potential environmental factors (e.g., landscape, soil, and groundwater), as well as conditions that could have driven sake brewers away from the coastal area. Many of the sake breweries that no longer exist were located on coastal dunes (i.e., sand, sandbanks, and natural levees) and obtained their water from a freshwater layer located 3-10 m below the surface. We speculate that these sake breweries benefited from using natural ingredients found in the coastal zone. We also investigated the following factors that may have negatively impacted the breweries, driving them out of business: (1) bankruptcies and reconstruction difficulties that followed the destructive 1923 Great Kanto earthquake, (2) industrial wartime adjustments during World War II (1939-1945), (3) development of coastal industries during the period from 1960 to 1975, and (4) increasing choices for other alcoholic drinks (e.g., beer, wine, and whiskey) from the 1960s to the present.[Figure not available: see fulltext.

  11. The role of vegetation in shaping dune morphology

    Science.gov (United States)

    Duran Vinent, O.; Moore, L. J.; Young, D.

    2012-12-01

    Aeolian dunes naturally emerge under strong winds and sufficient sand supply. They represent the most dynamical feature of the arid and/or coastal landscape and their evolution has the potential to either increase desertification or reduce coastal vulnerability to storms. Although large-scale dune morphology mainly depends on the wind regime and sand availability, vegetation plays an important role in semiarid and/or coastal areas. It is well known that under certain conditions vegetation is able to stabilize dunes, driving a morphological transformation from un-vegetated mobile crescent dunes to static vegetated "parabolic" dunes, de facto paralyzing desertification and initiating land recovery. Furthermore, vegetation is also the primary ingredient in the formation of coastal foredunes, which determine vulnerability to storms, as low dunes are prone to storm-induced erosion and overwash. In both cases, the coupling of biological and geomorphic (physical) processes, in particular vegetation growth and sand transport, governs the evolution of morphology. These processes were implemented in a computational model as part of a previous effort. It was shown that, for a migrating dune, this coupling leads to a negative feedback for dune motion, where an ever denser vegetation implies ever lesser sand transport. The model also predicted the existence of a "mobility index", defined by the vegetation growth rate to sand erosion rate ratio, that fully characterizes the morphological outcome: for indices above a certain threshold biological processes are dominant and dune motion slows after being covered by plants; for lower indices, the physical processes are the dominant ones and the dune remains mobile while vegetation is buried or rooted out. Here, we extend this model to better understand the formation of coastal dunes. We include new physical elements such as the shoreline and water table, as well as different grass species and potential competition among them

  12. Reconstruction of the coastal morphodynamics of the Fulong-beach dune field in north-eastern Taiwan

    Science.gov (United States)

    Dörschner, Nina; Böse, Margot; Frechen, Manfred

    2010-05-01

    The Fulong-beach dune field is located at the north-eastern coast of Taiwan. Built up of medium and fine grained quartz rich sand, it represents a unique feature of only few kilometres along the east coast of Taiwan. This unique sedimentological regime makes the area most perfectly suitable for age estimations by optically stimulated luminescence (OSL). The dune field is crossed by the Shuangsi-river, which flows into the Pacific Ocean. The coastal area is subjected to very dynamic conditions in the transition zone between land and sea. Due to the constant force of marine and aeolian processes from tides, weather and sediment accumulation by rivers, it is a continuously changing area. Taiwan is located in a very active tectonic zone with high elevation rates, which reach from 4 mm per year at the east coast up to 7 mm per year in the southern parts of the island. Furthermore Taiwan is affected by medial 3.8 typhoons per year and minor earthquakes nearly occur every day (LIN ET AL. 2006). The consequences are high rates of erosion and sediment transport during very short time periods. The Fulong-beach coastal area is densely populated and proud for being a tourism destination. At the northern end of the dune field the Lungmen nuclear power plant is currently under construction. Four separate dune ridges could be identified from a digital elevation model and from field mapping. During the field campaign in October and November 2009 17 samples were taken for OSL-dating (MURRAY ET AL. 1995) out of the four dune ridges as well as out of a more than 30 m high elevated outcrop cut by the Shuangsi-river. The measurement and the evaluation of the OSL-samples will provide us an insight into the duration and intensity of the processes affecting the coastal area of Taiwan during the Holocene. We will give an outline during the poster presentation of the methodical approach and the morphodynamical processes affecting the Fulong-beach dune field in north-eastern Taiwan

  13. The role of dunes in contrasting saltwater intrusion in coastal areas; a case study in the southern Po Plain Adriatic coast (Ravenna, Northern Italy)

    Science.gov (United States)

    Marconi, V.; Antonellini, M.; Balugani, E.; Minchio, A.; Gabbianelli, G.

    2009-04-01

    Due to climate changes and to anthropogenic interventions, saltwater intrusion is affecting the aquifers and the surface water of the Po plain along the Adriatic coast. During the last decade, we recognized in this area a pattern of climate change: precipitations are less frequent and the yearly amount of rain is concentrated in a few strong storm events. This pattern results in an increase of gales strength during the winter, which causes shoreline retreat and an erosion of the coastal dunes. The coastal part of the Po plain consists of a low-lying and mechanically-drained farmland further from the sea and of a narrow belt of dunes and pine forests in the backshore area. The wide sandy beaches are now retreating and the dune system (only a few meters in height) is almoust destroyed, because of tourism development and of disaggregated rivers and shorelines management. A still active dune system is preserved in our study area, a coastal plain included between the Fiumi Uniti and Bevano rivers near the city of Ravenna. As a result of an intensive exploitation of coastal aquifers for agricultural, industrial, and civil uses, both the phreatic aquifer and the surface waters have been contaminated by seawater. Despite its value for the natural ecosystem and the agricultural soil, the phreatic aquifer is not considered of interest by the regional authorities responsible for water management. A detailed hydrogeological survey was performed by our research group during the Summer 2008 within the framework of the CIRCLE-ERANET project WATERKNOW on the effects of climate change on the mediterranean catchments. In this survey 29 auger holes with an average spacing of 350 m where drilled with the objective of determining the top groundwater quality in the coastal aquifer. At the same time, we measured the chemical and physical parameters of the surface waters. The data collected in the field show that a fresh groundwater lens is still present in the aquifer of the backshore

  14. An evaluation of flora from coastal sand dunes of India: Rationale for conservation and management

    Digital Repository Service at National Institute of Oceanography (India)

    Rodrigues, R.S.; Mascarenhas, A.; Jagtap, T.G.

    stream_size 37100 stream_content_type text/plain stream_name Ocean_Coast_Manage_54_181a.pdf.txt stream_source_info Ocean_Coast_Manage_54_181a.pdf.txt Content-Encoding UTF-8 Content-Type text/plain; charset=UTF-8 1... Author version: Ocean & Coastal Management, vol.54(2); 2011; 181-188 An evaluation of flora from coastal sand dunes of India: Rationale for conservation and management Rouchelle S. Rodrigues, Antonio Mascarenhas, Tanaji G. Jagtap * National...

  15. Sand fences: An environment-friendly technique to restore degraded coastal dunes

    Digital Repository Service at National Institute of Oceanography (India)

    Mascarenhas, A.

    of prevailing winds (Matias et al. 2005). Our observations show that sand gets deposited 2 to 6 m downwind behind artificial barriers lying on the beach. A series of fences can therefore intercept wind-blown sand over a considerable area along the frontal beach..., but fashioned artificially; (e) Restoration of coastal dunes can be adopted wherever these features are damaged due to natural processes or human interference. Acknowledgements: The author is grateful to the Director, NIO, Goa, for permission to publish...

  16. Climate sensibility and stability of coastal dunes. Final report; Klimasensibilitaet und Stabiltaet nicht regenerierbarer Oekosysteme: Kuestenduenen. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Handelmann, D.; Klittmann, T.; Badenhop, J.; Folger, M.

    2000-07-01

    Coastal dunes have an important function as unique habitats for plants and animals as well as natural barriers against storm tides. Thus, they are of special value for nature conservation and coastal defence issues. Facing their potential endangering due to accelerated climate change profound knowledge of stabilty of coastal dunes is essential. In this context the presented study deals with the impact of climate change on biogenic sand stabilization in coastal dunes, which have to be conceived as an ecosystemic process. Questions of climate affected reactions of organism groups involved in this process (plants, soil microflora, soil fauna) and alterations in soil structure were followed up. Within the scope of a 2-years-lasting field experiment conducted on the Eastfrisian Island Norderney the microclimate near the soil surface was modified by gauze covering, which was set up on field plots. (orig.) [German] In ihrer Funktion als Lebensraum fuer Pflanzen und Tiere sowie als natuerlicher Schutzwall bei Sturmfluten wird den Kuestenduenen eine wichtige Bedeutung im Natur- und Kuestenschutz beigemessen. Angesichts ihrer potentiellen Gefaehrdung durch einen beschleunigten Klimawandel ist ein fundierter Kenntnisstand zur Stabilitaet von Kuestenduenen von elementarem Interesse. Vor diesem Hintergrund befasst sich die vorliegende Studie mit dem Einfluss von Klimaaenderungen auf die biogene Sandstabilisierung in Kuestenduenen, die aufgrund des bestehenden organismischen Beziehungsgeflechtes als oekosystemarer Prozess aufzufassen ist. Dabei wurden Fragen nach klimaabhaengigen Reaktionen der an diesem Prozess beteiligten Organismengruppen (Pflanzen, Bodenmikroflora, Bodenfauna) und Veraenderungen des Bodengefueges bearbeitet. Im Rahmen eines 2-jaehrigen Freilandexperimentes auf der Ostfriesischen Insel Norderney wurde das bodennahe Mikroklima mittels einer Gazeueberspannung auf 4 m{sup 2} grossen und mit Strandhafer (Calammophila baltica) bepflanzten Parzellen experimentell

  17. Responses to invasion and invader removal differ between native and exotic plant groups in a coastal dune.

    Science.gov (United States)

    Magnoli, Susan M; Kleinhesselink, Andrew R; Cushman, J Hall

    2013-12-01

    The spread of exotic, invasive species is a global phenomenon that is recognized as a major source of environmental change. Although many studies have addressed the effects of exotic plants on the communities they invade, few have quantified the effects of invader removal on plant communities, or considered the degree to which different plant groups vary in response to invasion and invader removal. We evaluated the effects of an exotic succulent, iceplant (Carpobrotus edulis), on a coastal dune plant community in northern California, as well as the community responses to its removal. To assess possible mechanisms by which iceplant affects other plants, we also evaluated its above- and belowground influences on the germination and growth of a dominant exotic annual grass, Bromus diandrus. We found that iceplant invasion was associated with reduced native plant cover as well as increased cover and density of some exotic plants-especially exotic annual grasses. However, iceplant removal did not necessarily lead to a reversal of these effects: removal increased the cover and density of both native and exotic species. We also found that B. diandrus grown in iceplant patches, or in soil where iceplant had been removed, had poorer germination and growth than B. diandrus grown in soil not influenced by iceplant. This suggests that the influence of iceplant on this dune plant community occurs, at least in part, due to belowground effects, and that these effects remain after iceplant has been removed. Our study demonstrates the importance of considering how exotic invasive plants affect not only native species, but also co-occurring exotic taxa. It also shows that combining observational studies with removal experiments can lead to important insights into the influence of invaders and the mechanisms of their effects.

  18. Natural versus Urban dunes along the Emilia-Romagna coast, Northern Adriatic (Italy)

    Science.gov (United States)

    Corbau, Corinne; Simeoni, Umberto

    2014-05-01

    Beach-dune interaction models can be precious tools for land managers and policymakers. However, if the models are inaccurate, land use policies may be designed based on false pretences or assumptions leading to poor land management, long-term erosion and sustainability issues, and increased difficulties in maintaining the dynamic coastal systems. From the literature, it appears that even the most reliable beach-dunes interactions models are not applicable to all coastal systems (Short and Hesp, 1982; Psuty, 1988; Sherman and Bauer, 1993). The study aims to identify the morphological evolution of the Emilia-Romagna coastal dunes according to its natural and "human" characteristics and to classify groups of dunes with similar evolutionary patterns. The coastal area consists essentially of 130 km of low sandy coast, interrupted by vast lagoon areas, harbor jetties and numerous hard coastal defense structures that were built during the first half of the 20th century to protect the Emilia-Romagna coast against erosion. Today about 57% of the littoral is protected by hard defenses, which have modified the morphodynamic characteristics of the beach without inverting the negative coastal evolution's trend. From recent aerial photographs (2011), 62 coastal dunes have been identified and mapped. Furthermore, the dune analysis shows a variability of the "physical characteristics" of coastal-dune systems along the Emilia-Romagna coast. The dune height varies from 1 to 7 meters, the width of the beach and of the active dunes range respectively from 10 to 150 m and from 10 to 65 m. Three main factors may explain the variability of the "physical characteristics": 1- Firstly the frontal dunes may be of different states according to the classification of Hesp (2002) since they correspond to incipient foredunes, well-developed foredunes, blowouts, residual foredunes as well as reactivated relict foredunes, 2- This could also be related to a different orientation of the coastline

  19. Response of the chitinolytic microbial community to chitin amendments of dune soils

    NARCIS (Netherlands)

    De Boer, W.; Gerards, S.; Klein Gunnewiek, P.J.A.; Modderman, R.

    1999-01-01

    The dynamics of culturable chitin-degrading microorganisms were studied during a 16-week incubation of chitin-amended coastal dune soils that differed in acidity. Soil samples were incubated at normal (5% Why) and high (15% w/w) moisture levels. More than half of the added chitin was decomposed

  20. What is a Dune: Developing AN Automated Approach to Extracting Dunes from Digital Elevation Models

    Science.gov (United States)

    Taylor, H.; DeCuir, C.; Wernette, P. A.; Taube, C.; Eyler, R.; Thopson, S.

    2016-12-01

    Coastal dunes can absorb storm surge and mitigate inland erosion caused by elevated water levels during a storm. In order to understand how a dune responds to and recovers from a storm, it is important that we can first identify and differentiate the beach and dune from the rest of the landscape. Current literature does not provide a consistent definition of what the dune features (e.g. dune toe, dune crest) are or how they can be extracted. The purpose of this research is to develop enhanced approaches to extracting dunes from a digital elevation model (DEM). Manual delineation, convergence index, least-cost path, relative relief, and vegetation abundance were compared and contrasted on a small area of Padre Island National Seashore (PAIS), Preliminary results indicate that the method used to extract the dune greatly affects our interpretation of how the dune changes. The manual delineation method was time intensive and subjective, while the convergence index approach was useful to easily identify the dune crest through maximum and minimum values. The least-cost path method proved to be time intensive due to data clipping; however, this approach resulted in continuous geomorphic landscape features (e.g. dune toe, dune crest). While the relative relief approach shows the most features in multi resolution, it is difficult to assess the accuracy of the extracted features because extracted features appear as points that can vary widely in their location from one meter to the next. The vegetation approach was greatly impacted by the seasonal and annual fluctuations of growth but is advantageous in historical change studies because it can be used to extract consistent dune formation from historical aerial imagery. Improving our ability to more accurately assess dune response and recovery to a storm will enable coastal managers to more accurately predict how dunes may respond to future climate change scenarios.

  1. Sedimentary rhythms in coastal dunes as a record of intra-annual changes in wind climate (Łeba, Poland)

    Science.gov (United States)

    Ludwig, J.; Lindhorst, S.; Betzler, C.; Bierstedt, S. E.; Borówka, R. K.

    2017-08-01

    It is shown that coastal dunes bear a so far unread archive of annual wind intensity. Active dunes at the Polish coast near Łeba consist of two genetic units: primary dunes with up to 18 m high eastward-dipping foresets, temporarily superimposed by smaller secondary dunes. Ground-penetrating radar (GPR) data reveal that the foresets of the primary dunes are bundled into alternating packages imaged as either low- or high-amplitude reflections. High-amplitude packages are composed of quartz sand with intercalated heavy-minerals layers. Low-amplitude packages lack these heavy-mineral concentrations. Dune net-progradation is towards the east, reflecting the prevalence of westerly winds. Winds blowing parallel to the dune crest winnow the lee slope, leaving layers enriched in heavy minerals. Sediment transport to the slip face of the dunes is enhanced during the winter months, whereas winnowing predominantly takes place during the spring to autumn months, when the wind field is bi-directional. As a consequence of this seasonal shift, the sedimentary record of one year comprises one low- and one high-amplitude GPR reflection interval. This sedimentary pattern is a persistent feature of the Łeba dunes and recognized to resemble a sedimentary "bar code". To overcome hiatuses in the bar code of individual dunes and dune-to-dune variations in bar-code quality, dendrochronological methods were adopted to compile a composite bar code from several dunes. The resulting data series shows annual variations in west-wind intensity at the southern Baltic coast for the time period 1987 to 2012. Proxy-based wind data are validated against instrumental based weather observations.

  2. The potential of Tillandsia dune ecosystems for revealing past and present variations in advective fog along the coastal Atacama Desert, northern Chile

    Science.gov (United States)

    Latorre Hidalgo, C.; García, J. L.; Gonzalez, A. L.; Marquet, P. A.

    2015-12-01

    The coastal Atacama Desert is home to a complex geo-ecosystem supported by fog with multiple atmospheric and oceanic drivers. Fog collectors in place for the last 17 years reveal that monthly fog intensity and amount are significantly linked to the El Niño-Southern Oscillation (ENSO 1+2) with cold (warm) anomalies correlated to increased (decreased) fog (R2 = 0.41). Rainfall, however, can occur during extreme positive ENSO anomalies. Tillandsia landbeckii is an epiarenitic plant common to the coastal Atacama where fog is intercepted by the coastal escarpment between 950-1250 m.a.s.l. These plants possess multiple adaptations to survive exclusively on fog, including the construction of "dune" ecosystems known as "tillandsiales". Buried T. landbeckii layers in such dunes contain a record of past variations of fog over time (dunes can top 3 m in height) and alternating plant and sand layers are readily visible in dune stratigraphy. Stable N isotopes on modern plants and fog indicate that these plants reflect δ15N values of total N dissolved in fog. We measured δ15N values from buried T. landbeckii layers from five different tillandsiales found across c. 50 km the coastal escarpment. The isotope values in these buried plants indicate a prominent c. 8.0 ‰ shift towards more negative δ15N values on average over the last 3,200 years. Based on differences in δ15N between modern and more extensive "paleo" tillandsiales at one of our lowest elevation study sites, we interpret this shift as an increase in available moisture due to increased fog input during the late Holocene. Increased variability in ENSO as well as increased upwelling and southerly winds along the coastal Atacama would explain in part this increase. Clearly, the Atacama tillandsiales have considerable potential for monitoring past and present change of these large-scale ocean-atmosphere systems.

  3. Reattachment Zone Characterisation Under Offshore Winds With Flow Separation On The Lee Side Of Coastal Dunes

    Science.gov (United States)

    Delgado-Fernandez, I.; Jackson, D.; Cooper, J. A.; Baas, A. C.; Lynch, K.; Beyers, M.

    2010-12-01

    Airflow separation, lee-side eddies and secondary flows play an essential role on the formation and maintenance of sand dunes. Downstream from dune crests the flow surface layer detaches from the ground and generates an area characterised by turbulent eddies in the dune lee slope (the wake). At some distance downstream from the dune crest, flow separates into a reversed component directed toward the dune toe and an offshore “re-attached” component. This reattachment zone (RZ) has been documented in fluvial and desert environments, wind tunnel experiments and numerical simulations, but not yet characterised in coastal dunes. This study examines the extent and temporal evolution of the RZ and its implications for beach-dune interaction at Magilligan, Northern Ireland. Wind parameters were measured over a profile extending from an 11 m height dune crest towards the beach, covering a total distance of 65 m cross-shore. Data was collected using an array of nine ultrasonic anemometers (UAs) deployed in April-May 2010, as part of a larger experiment to capture airflow data under a range of incident wind velocities and offshore directions. UAs were located along the profile (5 m tower spacing) over the beach, which allowed a detailed examination of the RZ with empirical data. Numerical modelling using Computational Fluid Dynamics (CFD) software was also conducted with input data from anemometer field measurements, running over a surface mesh generated from LiDAR and DGPS surveys. Results demonstrate that there is a wind threshold of approximately 5-6 ms-1 under which no flow separation exists with offshore winds. As wind speed increases over the threshold, a flow reversal area is quickly formed, with the maximum extent of the RZ at approximately 3.5 dune heights (h). The maximum extent of the RZ increases up to 4.5h with stronger wind speeds of 8-10 ms-1 and remains relatively constant as wind speed further increases. This suggests that the spatial extent of the RZ is

  4. Changes in Microbial Community Structure and Soil Biological Properties in Mined Dune Areas During Re-vegetation.

    Science.gov (United States)

    Escobar, Indra Elena C; Santos, Vilma M; da Silva, Danielle Karla A; Fernandes, Marcelo F; Cavalcante, Uided Maaze T; Maia, Leonor C

    2015-06-01

    The aim of this study was to describe the impact of re-vegetation on the restoration of microbial community structure and soil microbiological properties in sand dunes that had been affected by mining activity. Soil samples were collected during the dry and rainy seasons from a chronosequence (1, 9, 21 years) of re-vegetated dunes using a single preserved dune as a reference. The composition of the fatty acid methyl esters and soil microbial properties were evaluated. The results showed that the changes in microbial community structure were related to seasonal variations: biomarkers of Gram-positive bacteria were higher than Gram-negative bacteria during the dry season, showing that this group of organisms is more tolerant to these stressful conditions. The microbial community structure in the natural dune was less affected by seasonal variation compared to the re-vegetated areas, whereas the opposite was observed for microbiological properties. Thus, in general, the proportion of saprobic fungi was higher in the natural dune, whereas Gram-negative bacteria were proportionally more common in the younger areas. Although over time the re-vegetation allows the recovery of the microbial community and the soil functions, these communities and functions are different from those found in the undisturbed areas.

  5. A methodological approach to assess beach-dune system susceptibility to erosion. Cases studies from Valdelagrana spit (Spain) and Campomarino beach (Italy).

    Science.gov (United States)

    Rizzo, Angela; Aucelli, Pietro P. C.; Gracia, Javier F.; Anfuso, Giorgio; Rosskopf, Carmen M.

    2016-04-01

    Dunes provide many important services to coastal areas, such as coastal erosion mitigation, coastal flooding protection and biological diversity. Their dynamic equilibrium and geomorphological evolution are the result of the interaction between marine and aeolian processes. Moreover, coastal dunes are characterized by a high ecological value, being a narrow strip between marine and terrestrial ecosystems and are habitats considered of community interest by the Habitats Directive 92/43/EEC. In the meantime, the significant increase of human pressure on coastal environments during the last decades has caused a strong alteration and an increase of the fragility and fragmentation of these habitats. This paper presents a methodological approach for the assessment of the beach-dune system susceptibility to erosion. The aim is to identify, at the local scale, the degree of susceptibility of coastal stretches in order to evaluate the degree of exposure of human settlements and natural environments located behind the dune system and to support actuations to appropriately improve dune management and conservation. A coastal susceptibility matrix and a corresponding Coastal Susceptibility Index (CSI) are proposed. Following the assumption that a good index should be based on a minimum amount of essential information (Cooper and McLaughlin, 1998), possibly already available or easy to be obtained (Villa and McLeod, 2002), the proposed index consisted into eight variables concerning existing beach and dune conditions, covering geomorphological, physical and anthropogenic aspects. Each variable was inserted into a GIS system and overlapped with the others through a logical overlay operation. The resulting layer was reclassified according to the formula proposed by Rangel and Anfuso (2015) allowing to calculate the CSI, which ranged from 1 (null/very low susceptibility) to 5 (very high susceptibility). In a further step, the predominant processes occurred in the last decades were

  6. Antioxidant activity of raw, cooked and Rhizopus oligosporus fermented beans of Canavalia of coastal sand dunes of Southwest India.

    Science.gov (United States)

    Niveditha, Vedavyas R; Sridhar, Kandikere R

    2014-11-01

    The raw and processed (cooked and cooked + solid-state fermented with Rhizopus oligosporus) split beans of two landraces of coastal sand dune wild legumes (Canavalia cathartica and Canavalia maritima) of the southwest coast of India were examined for bioactive compounds (total phenolics, tannins and vitamin C) and antioxidant potential (total antioxidant activity, ferrous-ion chelating capacity, DPPH free radical-scavenging activity and reducing activity). One-way ANOVA revealed significant elevation of bioactive compounds as well as antioxidant activities in fermented beans compared to raw and cooked beans in both legumes (p beans of both legumes were significantly lowest compared to raw and cooked beans (p beans of C. cathartica, while total antioxidant and free radical-scavenging activities of fermented beans of C. maritima were clustered. The present study demonstrated that split beans of coastal sand dune Canavalia fermented by R. oligosporus endowed with high bioactive principles as well as antioxidant potential and thus serve as future nutraceutical source.

  7. Does salt stress constrain spatial distribution of dune building grasses Ammophila arenaria and Elytrichia juncea on the beach?

    NARCIS (Netherlands)

    Puijenbroek, van M.E.B.; Teichmann, C.; Meijdam, Noortje; Oliveras Menor, I.; Berendse, F.; Limpens, J.

    2017-01-01

    Rising sea levels threaten coastal safety by increasing the risk of flooding. Coastal dunes provide a natural form of coastal protection. Understanding drivers that constrain early development of dunes is necessary to assess whether dune development may keep pace with sea-level rise. In this study,

  8. The use of time-series LIDAR to understand the role of foredune blowouts in coastal dune dynamics, Sefton, NW England.

    Science.gov (United States)

    O'Keeffe, Nicholas; Delgado-Fernandez, Irene; Aplin, Paul; Jackson, Derek; Marston, Christopher

    2017-04-01

    Coastal dunes are natural buffers against the threat of climate change-induced sea level rise. Their evolution is largely controlled by sediment exchanges between the geomorphic sub-units of the nearshore, beach, foredune and dune field. Coastlines characterised by multiple blowouts at the beach-dune interface may be more susceptible to coastline retreat through the enhanced landwards transport of beach and foredune sediment. This study, based in Sefton, north-west England, exploits an unprecedented temporal coverage of LIDAR surveys spanning 15 years (1999, 2008, 2010, 2013 and 2014). Established GIS techniques have been utilised to extract both the coastline (foredune toe) and the foredune crest from each LIDAR derived DTM (Digital Terrain Model). Migration of the foredune toe has been tracked over this period. Analysis of differentials between the height of the dune toe and dune crest have been used to locate the alongshore position of blowouts within the foredune. Dune sediment budgets have then been calculated for each DTM and analysis of the budgets conducted, with the coastline being compartmentalised alongshore, based on presence of blowouts within the foredune. Results indicate that sections of the coastline where blowouts are present within the foredune may be most vulnerable to coastline retreat. Temporal changes in the sediment budget within many of these sections also provides evidence that, if blowouts are present, coastline retreat continues to be a possibility even when the dune sediment budget remains positive.

  9. Effects of sand fences on coastal dune vegetation distribution

    Science.gov (United States)

    Grafals-Soto, Rosana

    2012-04-01

    Sand fences are important human adjustments modifying the morphology of developed shores. The effects of sand fences on sediment transport and deposition in their initial stages have been well studied, but little is known about the effect of deteriorated sand fences that have become partially buried low scale barriers within the dune, potentially benefiting vegetation growth by protecting it from onshore stress. Data on vegetation, topography and fence characteristics were gathered at three dune sites in Ocean City, New Jersey on September 2007 and March 2008 to evaluate the effect of fences within the dune on vegetation distribution. Variables include: distance landward of dune toe, degree of sheltering from onshore stressors, net change in surface elevation (deposition or erosion), vegetation diversity and density, presence of remnant fence, and distance landward of fence. Results for the studied environment reveal that 1) vegetation diversity or density does not increase near remnant fences because most remnants are lower than average vegetation height and can not provide shelter; but 2) vegetation distribution is related to topographic variables, such as degree of sheltering, that are most likely the result of sand accretion caused by fence deployment. Fence deployment that prioritizes the creation of topographically diverse dunes within a restricted space may increase the diversity and density of the vegetation, and the resilience and value of developed dunes. Managers should consider the benefits of using sand fences on appropriately wide beaches to create a protective dune that is also diverse, functional and better able to adapt to change.

  10. Linking marine resources to ecotonal shifts of water uptake by terrestrial dune vegetation.

    Science.gov (United States)

    Greaver, Tara L; Sternberg, Leonel L da S

    2006-09-01

    As evidence mounts that sea levels are rising, it becomes increasingly important to understand the role of ocean water within terrestrial ecosystem dynamics. Coastal sand dunes are ecosystems that occur on the interface of land and sea. They are classic ecotones characterized by zonal distribution of vegetation in response to strong gradients of environmental factors from the ocean to the inland. Despite the proximity of the dune ecosystem to the ocean, it is generally assumed that all vegetation utilizes only freshwater and that water sources do not change across the ecotone. Evidence of ocean water uptake by vegetation would redefine the traditional interpretation of plant-water relations in the dune ecosystem and offer new ideas for assessing maritime influences on function and spatial distribution of plants across the dune. The purpose of this study was to identify sources of water (ocean, ground, and rain) taken up by vegetation using isotopic analysis of stem water and to evaluate water uptake patterns at the community level based on the distribution and assemblage of species. Three coastal dune systems located in southern Florida, USA, and the Bahamian bank/platform system were investigated. Plant distributions across the dune were zonal for 61-94% of the 18 most abundant species at each site. Species with their highest frequency on the fore dune (nearest the ocean) indicate ocean water uptake as evidenced by delta 18O values of stem water. In contrast, species most frequent in the back dune show no evidence of ocean water uptake. Analysis of species not grouped by frequency, but instead sampled along a transect from the ocean toward the inland, indicates that individuals from the vegetation assemblage closest to the ocean had a mixed water-harvesting strategy characterized by plants that may utilize ocean, ground-, and/or rainwater. In contrast, the inland vegetation relies mostly on rainwater. Our results show evidence supporting ocean water use by dune

  11. Extraction of lidar-based dune-crest elevations for use in examining the vulnerability of beaches to inundation during hurricanes

    Science.gov (United States)

    Stockdon, H.F.; Doran, K.S.; Sallenger, A.H.

    2009-01-01

    The morphology of coastal sand dunes plays an important role in determining how a beach will respond to a hurricane. Accurate measurements of dune height and position are essential for assessing the vulnerability of beaches to extreme coastal change during future landfalls. Lidar topographic surveys provide rapid, accurate, high-resolution datasets for identifying the location, position, and morphology of coastal sand dunes over large stretches of coast. An algorithm has been developed for identification of the crest of the most seaward sand dune that defines the landward limit of the beach system. Based on changes in beach slope along cross-shore transects of lidar data, dune elevation and location can automatically be extracted every few meters along the coastline. Dune elevations in conjunction with storm-induced water levels can be used to predict the type of coastal response (e.g., beach erosion, dune erosion, overwash, or inundation) that may be expected during hurricane landfall. The vulnerability of the beach system at Fire Island National Seashore in New York to the most extreme of these changes, inundation, is assessed by comparing lidar-derived dune elevations to modeled wave setup and storm surge height. The vulnerability of the beach system to inundation during landfall of a Category 3 hurricane is shown to be spatially variable because of longshore variations in dune height (mean elevation 5.44 m, standard deviation 1.32 m). Hurricane-induced mean water levels exceed dune elevations along 70 of the coastal park, making these locations more vulnerable to inundation during a Category 3 storm. ?? 2009 Coastal Education and Research Foundation.

  12. Medium and large sized mammal assemblages in coastal dunes and adjacent marshes in southern Rio Grande do Sul State, Brazil - doi: 10.4025/actascibiolsci.v35i1.11705

    Directory of Open Access Journals (Sweden)

    Eduardo Resende Secchi

    2012-12-01

    Full Text Available This paper presents data on species composition and use of habitat of medium and large sized mammal assemblages in a coastal dunes segment and adjacent marshes at Rio Grande municipality, southern Rio Grande do Sul State, Brazil. Records were obtained through visualization of living animals and identification of footprints, feces and remains. From November 2007 to September 2008, nine 600 m long and 5 m wide linear transects were settled on coastal dunes segment (frontal and intermediate dunes and adjacent marshes, parallel to ocean shore on a 23 km section at Cassino Beach. Transects were settled in areas under high, medium and low levels of anthropic occupancy (A1, A2 and A3, respectively, being three transects on each area. Fourteen species were recorded, distributed in five orders and 10 families. Lepus europaeus was the most frequent species (81.9% of the transect walks, present in all areas and seasons, followed by Lycalopex gimnocercus (23.5% and Conepatus chinga (10.3%.  Five species were present on A1, seven on A2 and fourteen on A3. Seven species were recorded on frontal dunes, nine on intermediate dunes and 13 on adjacent marshes.  

  13. ECOLOGICAL INTELLIGENCE OF COASTAL COMMUNITY ON BIODIVERSITY CONSERVATION (Case Study of Bajau Coastal Communities, Gorontalo

    Directory of Open Access Journals (Sweden)

    Ramli Utina

    2017-04-01

    Full Text Available Human behavior is a part of the ecological system, therefore overcoming the ecological crisis and living resources need to explore human traditions, way of life and human behavior toward natural resources. Understanding and translation of human harmonious relationship with all elements along with other living beings is a form of human ecological intelligence. The objective of this study was to describe the traditions and coastal communities behavior that contains the value of ecological intelligence in coastal biodiversity conservation. The study was based on observation, focus group discussion and identification of Bajau coastal community tradition in their lives and livelihoods on fishing, as well as the behavior toward biological resources. Bajau coastal communities settled in three villages in Pohuwato regency, Gorontalo. There are two themes that contains the value of ecological intelligence of  Bajau communities in the conservation of biodiversity, namely; mamia kadialo in tradition of fishing, and fishing behavior. The prohibition in the tradition of mamia kadialo contains the value of conservation of biodiversity. Usage of simple equipment on fishing activities provide a positive ecological consequences for the conservation of coastal biodiversity.

  14. Coastal Engineering

    NARCIS (Netherlands)

    Van der Velden, E.T.J.M.

    1989-01-01

    Introduction, waves, sediment transport, littoral transport, lonshore sediment transport, onshore-offshore sediment transport, coastal changes, dune erosion and storm surges, sedimentation in channels and trenches, coastal engineering in practice.

  15. Assessment of Damage and Adaptation Strategies for Structures and Infrastructure from Storm Surge and Sea Level Rise for a Coastal Community in Rhode Island, United States

    Directory of Open Access Journals (Sweden)

    Christopher Small

    2016-10-01

    Full Text Available This paper presents an evaluation of inundation, erosion, and wave damage for a coastal community in Rhode Island, USA. A methodology called the Coastal Environmental Risk Index (CERI was used that incorporates levels of inundation including sea level rise, wave heights using STWAVE, and detailed information about individual structures from an E911 database. This information was input into damage functions developed by the U.S. Army Corps of Engineers following Hurricane Sandy. Damage from erosion was evaluated separately from local published erosion rates. Using CERI, two different adaptation strategies were evaluated that included a combination of dune restoration, protective berms, and a tide gate. A total of 151 out of 708 structures were estimated to be protected from inundation and wave action by the combined measures. More importantly, the use of CERI allowed for the assessment of the impact of different adaptation strategies on both individual structures and an entire community in a Geographical Information Systems (GIS environment. This tool shows promise for use by coastal managers to assess damage and mitigate risk to coastal communities.

  16. Barrier island morphology and sediment characteristics affect the recovery of dune building grasses following storm-induced overwash.

    Science.gov (United States)

    Brantley, Steven T; Bissett, Spencer N; Young, Donald R; Wolner, Catherine W V; Moore, Laura J

    2014-01-01

    Barrier islands are complex and dynamic systems that provide critical ecosystem services to coastal populations. Stability of these systems is threatened by rising sea level and the potential for coastal storms to increase in frequency and intensity. Recovery of dune-building grasses following storms is an important process that promotes topographic heterogeneity and long-term stability of barrier islands, yet factors that drive dune recovery are poorly understood. We examined vegetation recovery in overwash zones on two geomorphically distinct (undisturbed vs. frequently overwashed) barrier islands on the Virginia coast, USA. We hypothesized that vegetation recovery in overwash zones would be driven primarily by environmental characteristics, especially elevation and beach width. We sampled species composition and environmental characteristics along a continuum of disturbance from active overwash zones to relict overwash zones and in adjacent undisturbed environments. We compared species assemblages along the disturbance chronosequence and between islands and we analyzed species composition data and environmental measurements with Canonical Correspondence Analysis to link community composition with environmental characteristics. Recovering and geomorphically stable dunes were dominated by Ammophila breviligulata Fernaud (Poaceae) on both islands while active overwash zones were dominated by Spartina patens (Aiton) Muhl. (Poaceae) on the frequently disturbed island and bare sand on the less disturbed island. Species composition was associated with environmental characteristics only on the frequently disturbed island (p = 0.005) where A. breviligulata was associated with higher elevation and greater beach width. Spartina patens, the second most abundant species, was associated with larger sediment grain size and greater sediment size distribution. On the less frequently disturbed island, time since disturbance was the only factor that affected community

  17. Barrier island morphology and sediment characteristics affect the recovery of dune building grasses following storm-induced overwash.

    Directory of Open Access Journals (Sweden)

    Steven T Brantley

    Full Text Available Barrier islands are complex and dynamic systems that provide critical ecosystem services to coastal populations. Stability of these systems is threatened by rising sea level and the potential for coastal storms to increase in frequency and intensity. Recovery of dune-building grasses following storms is an important process that promotes topographic heterogeneity and long-term stability of barrier islands, yet factors that drive dune recovery are poorly understood. We examined vegetation recovery in overwash zones on two geomorphically distinct (undisturbed vs. frequently overwashed barrier islands on the Virginia coast, USA. We hypothesized that vegetation recovery in overwash zones would be driven primarily by environmental characteristics, especially elevation and beach width. We sampled species composition and environmental characteristics along a continuum of disturbance from active overwash zones to relict overwash zones and in adjacent undisturbed environments. We compared species assemblages along the disturbance chronosequence and between islands and we analyzed species composition data and environmental measurements with Canonical Correspondence Analysis to link community composition with environmental characteristics. Recovering and geomorphically stable dunes were dominated by Ammophila breviligulata Fernaud (Poaceae on both islands while active overwash zones were dominated by Spartina patens (Aiton Muhl. (Poaceae on the frequently disturbed island and bare sand on the less disturbed island. Species composition was associated with environmental characteristics only on the frequently disturbed island (p = 0.005 where A. breviligulata was associated with higher elevation and greater beach width. Spartina patens, the second most abundant species, was associated with larger sediment grain size and greater sediment size distribution. On the less frequently disturbed island, time since disturbance was the only factor that affected

  18. SPINIFICI-SCAEVOLETEA SERICEAE, A NEW VEGETATION CLASS FOR PSAMMOPHYTIC DUNE VEGETATION IN THAILAND

    Directory of Open Access Journals (Sweden)

    S. PIGNATII

    1996-04-01

    Full Text Available This is a short account on the coastal dune vegetation of the Gulf of Siam in Thailand. Vegetation is mainly composed by succulent creeping plants with herbaceous habit as to Canavalia maritima (Papilionaceae and Iponwea pes-caprae (Convolvulaceae and the robust stoloniferous grass Spinijex littoreus, the last having an important function for the fonnation of coastal dunes.

  19. SPINIFICI-SCAEVOLETEA SERICEAE, A NEW VEGETATION CLASS FOR PSAMMOPHYTIC DUNE VEGETATION IN THAILAND

    Directory of Open Access Journals (Sweden)

    S. PIGNATII

    1996-01-01

    Full Text Available This is a short account on the coastal dune vegetation of the Gulf of Siam in Thailand. Vegetation is mainly composed by succulent creeping plants with herbaceous habit as to Canavalia maritima (Papilionaceae and Iponwea pes-caprae (Convolvulaceae and the robust stoloniferous grass Spinijex littoreus, the last having an important function for the fonnation of coastal dunes.

  20. Strategies in Mobilizing Coastal Communities for Community-Based Coastal Resource Management in Bolinao, Pangasinan

    Directory of Open Access Journals (Sweden)

    Jacquelyn Pinat

    2000-12-01

    Full Text Available The Marine Fishery Resources Management Project (MFRMP hopes to facilitate partnership between the local government unit and the local communities in managing the coastal resources of Bolinao. Mobilization, both at the community and municipal levels, has been very important in promoting community-based strategies in coastal resources management. The community organization process in the municipality has gone through several levels; and different organizations have been formed. In empowering individuals and organizations, strategies tend to be varied and fluid depending on the need, the reason for mobilization, and the resources at hand. The Bolinao experience showcases different strategies used in implementing the resource enhancement, coastal zoning, harvest regulation, and capability building components of the program. These have included the formation of people's organizations, the mobilization of zonal action teams for each of the four zones, the creation and orientation of fishery and aquatic resources management councils at the barangay and municipal levels, and the active collaboration with the local government unit. These strategies and approaches have provided the people and the communities a wealth of experience and lessons that provide helpful insights in undertaking different endeavors. The strategies employed in the mobilization activities have significantly contributed to the empowerment of communities and individuals who are the primary managers of their resources.

  1. How extensive is the effect of modern farming on bird communities in a sand dune desert?

    Directory of Open Access Journals (Sweden)

    Faris Khoury

    2009-12-01

    Full Text Available Bird community structure and diversity measures in sand dune habitats far from and close to modern farms in Wadi Araba, south-west Jordan, were compared using 52 line transects for breeding birds and habitat variables. A change in the bird community of sand dunes surrounding farming projects was measured to a distance of 1 km, but could neither be related to changes in habitat structure nor to the activity of op- portunistic predators (Red Fox as these did not vary significantly between the two samples. The farms included lines of trees and offered a constant source of water, which attracted a variety of opportunistic species, thus increasing bird diversity and total bird abundances. The absence of characteristic ground-dwelling species of open sand dune habitats in the structurally intact sand dunes surrounding farms was likely to be the result of localized, but effectively far-reaching habitat modification (farms acting as barriers and/or competition with some of the opportunistic species, which were common around farms.

  2. Dune communities of SE Colorado: Patterns of rarity, disjunction and succession

    Science.gov (United States)

    T. Kelso; N. Bower; P. Halteman; K. Tenney; S. Weaver

    2007-01-01

    Dune communities occur across the western Great Plains and in isolated spots in eastern Colorado. They are biologically important due to their endemic nature, their rapid succession, and their ephemeral abundance in response to climate, grazing practices, and ranchland management. The abundance of these terrestrial islands has changed considerably over scales from tens...

  3. Impacts of cattle on ecological restoration of coastal forests in ...

    African Journals Online (AJOL)

    Livestock from communities bordered by dune mining, urban areas and commercial forestry in northern KwaZulu-Natal spend substantial time foraging in the coastal forest that the mining company is obliged to restore. A survey of livestock owners and an experimental study of impacts of cattle on restoration processes were ...

  4. The role of bathymetry, wave obliquity and coastal curvature in dune erosion prediction

    NARCIS (Netherlands)

    Den Heijer, C.

    2013-01-01

    This study aims at reducing uncertainty in dune erosion predictions, in particular at complex dune coasts, in order to improve the assessment method for dune safety against flooding. To that end, state-of-the-art process-based dune erosion models are employed to further investigate issues

  5. Exploring the contributions of vegetation and dune size to early dune development using unmanned aerial vehicle (UAV) imaging

    Science.gov (United States)

    van Puijenbroek, Marinka E. B.; Nolet, Corjan; de Groot, Alma V.; Suomalainen, Juha M.; Riksen, Michel J. P. M.; Berendse, Frank; Limpens, Juul

    2017-12-01

    distance to the sea. Our results show that dune growth in summer is mainly determined by dune size, whereas in winter dune growth was determined by vegetation type. In our study area the growth of exposed dunes was likely restricted by storm erosion, whereas growth of sheltered dunes was restricted by sand supply. Our results can be used to improve models predicting coastal dune development.

  6. Development of spatially diverse and complex dune-field patterns: Gran Desierto Dune Field, Sonora, Mexico

    Science.gov (United States)

    Beveridge, C.; Kocurek, G.; Ewing, R.C.; Lancaster, N.; Morthekai, P.; Singhvi, A.K.; Mahan, S.A.

    2006-01-01

    The pattern of dunes within the Gran Desierto of Sonora, Mexico, is both spatially diverse and complex. Identification of the pattern components from remote-sensing images, combined with statistical analysis of their measured parameters demonstrate that the composite pattern consists of separate populations of simple dune patterns. Age-bracketing by optically stimulated luminescence (OSL) indicates that the simple patterns represent relatively short-lived aeolian constructional events since ???25 ka. The simple dune patterns consist of: (i) late Pleistocene relict linear dunes; (ii) degraded crescentic dunes formed at ???12 ka; (iii) early Holocene western crescentic dunes; (iv) eastern crescentic dunes emplaced at ???7 ka; and (v) star dunes formed during the last 3 ka. Recognition of the simple patterns and their ages allows for the geomorphic backstripping of the composite pattern. Palaeowind reconstructions, based upon the rule of gross bedform-normal transport, are largely in agreement with regional proxy data. The sediment state over time for the Gran Desierto is one in which the sediment supply for aeolian constructional events is derived from previously stored sediment (Ancestral Colorado River sediment), and contemporaneous influx from the lower Colorado River valley and coastal influx from the Bahia del Adair inlet. Aeolian constructional events are triggered by climatic shifts to greater aridity, changes in the wind regime, and the development of a sediment supply. The rate of geomorphic change within the Gran Desierto is significantly greater than the rate of subsidence and burial of the accumulation surface upon which it rests. ?? 2006 The Authors. Journal compilation 2006 International Association of Sedimentologists.

  7. Experiment Simulation Configurations Used in DUNE CDR

    Energy Technology Data Exchange (ETDEWEB)

    Alion, T. [Univ. of South Carolina, Columbia, SC (United States); Black, J. J. [Univ. of Warwick, Coventry (United Kingdom); Bashyal, A. [Oregon State Univ., Corvallis, OR (United States); Bass, M. [Univ. of Oxford (United Kingdom); Bishai, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Cherdack, D. [Colorado State Univ., Fort Collins, CO (United States); Diwan, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Djurcic, Z. [Argonne National Lab. (ANL), Argonne, IL (United States); Evans, J. [Univ. of Manchester (United Kingdom); Fernandez-Martinez, E. [Madrid Autonama Univ. (Spain); Fields, L. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Fleming, B. [Yale Univ., New Haven, CT (United States); Gran, R. [Univ. of Minnesota, Duluth, MN (United States); Guenette, R. [Univ. of Oxford (United Kingdom); Hewes, J. [Univ. of Manchester (United Kingdom); Hogan, M. [Colorado State Univ., Fort Collins, CO (United States); Hylen, J. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Junk, T. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Kohn, S. [Univ. of California, Berkeley, CA (United States); LeBrun, P. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lundberg, B. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Marchionni, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Morris, C. [Univ. of California, Berkeley, CA (United States); Papadimitriou, V. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Rameika, R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Rucinski, R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Soldner-Rembold, S. [Univ. of Manchester (United Kingdom); Sorel, M. [Spanish National Research Council (CSIC), Valencia (Spain). Univ. of Valencia (UV), Inst. de Fisica Corpuscular; Urheim, J. [Indiana Univ., Bloomington, IN (United States); Viren, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Whitehead, L. [Univ. of Houston, TX (United States); Wilson, R. [Colorado State Univ., Fort Collins, CO (United States); Worcester, E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zeller, G. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2016-06-30

    The LBNF/DUNE CDR describes the proposed physics program and experimental design at the conceptual design phase. Volume 2, entitled The Physics Program for DUNE at LBNF, outlines the scientific objectives and describes the physics studies that the DUNE collaboration will perform to address these objectives. The long-baseline physics sensitivity calculations presented in the DUNE CDR rely upon simulation of the neutrino beam line, simulation of neutrino interactions in the far detector, and a parameterized analysis of detector performance and systematic uncertainty. The purpose of this posting is to provide the results of these simulations to the community to facilitate phenomenological studies of long-baseline oscillation at LBNF/DUNE. Additionally, this posting includes GDML of the DUNE single-phase far detector for use in simulations. DUNE welcomes those interested in performing this work as members of the collaboration, but also recognizes the benefit of making these configurations readily available to the wider community.

  8. Short- and longterm impacts of Acacia longifolia invasion on belowground processes of a Mediterranean coastal dune ecosystem

    DEFF Research Database (Denmark)

    Marchante, Elizabete; Kjøller, Annelise; Struwe, Sten

    2008-01-01

    to new areas, displacing the native vegetation. These invaded ecosystems contrast with the native dune ecosystems that are typically dominated by herb and shrub communities. This study characterizes belowground changes to the native environment as a result of recent (20 y...

  9. Minimal size of a barchan dune

    Science.gov (United States)

    Parteli, E. J. R.; Durán, O.; Herrmann, H. J.

    2007-01-01

    Barchans are dunes of high mobility which have a crescent shape and propagate under conditions of unidirectional wind. However, sand dunes only appear above a critical size, which scales with the saturation distance of the sand flux [P. Hersen, S. Douady, and B. Andreotti, Phys. Rev. Lett. 89, 264301 (2002); B. Andreotti, P. Claudin, and S. Douady, Eur. Phys. J. B 28, 321 (2002); G. Sauermann, K. Kroy, and H. J. Herrmann, Phys. Rev. E 64, 31305 (2001)]. It has been suggested by P. Hersen, S. Douady, and B. Andreotti, Phys. Rev. Lett. 89, 264301 (2002)] that this flux fetch distance is itself constant. Indeed, this could not explain the protosize of barchan dunes, which often occur in coastal areas of high litoral drift, and the scale of dunes on Mars. In the present work, we show from three-dimensional calculations of sand transport that the size and the shape of the minimal barchan dune depend on the wind friction speed and the sand flux on the area between dunes in a field. Our results explain the common appearance of barchans a few tens of centimeter high which are observed along coasts. Furthermore, we find that the rate at which grains enter saltation on Mars is one order of magnitude higher than on Earth, and is relevant to correctly obtain the minimal dune size on Mars.

  10. Testing model parameters for wave‐induced dune erosion using observations from Hurricane Sandy

    Science.gov (United States)

    Overbeck, Jacquelyn R.; Long, Joseph W.; Stockdon, Hilary F.

    2017-01-01

    Models of dune erosion depend on a set of assumptions that dictate the predicted evolution of dunes throughout the duration of a storm. Lidar observations made before and after Hurricane Sandy at over 800 profiles with diverse dune elevations, widths, and volumes are used to quantify specific dune erosion model parameters including the dune face slope, which controls dune avalanching, and the trajectory of the dune toe, which controls dune migration. Wave‐impact models of dune erosion assume a vertical dune face and erosion of the dune toe along the foreshore beach slope. Observations presented here show that these assumptions are not always valid and require additional testing if these models are to be used to predict coastal vulnerability for decision‐making purposes. Observed dune face slopes steepened by 43% yet did not become vertical faces, and only 50% of the dunes evolved along a trajectory similar to the foreshore beach slope. Observations also indicate that dune crests were lowered during dune erosion. Moreover, analysis showed a correspondence between dune lowering and narrower beaches, smaller dune volumes, and/or longer wave impact.

  11. Testing model parameters for wave-induced dune erosion using observations from Hurricane Sandy

    Science.gov (United States)

    Overbeck, J. R.; Long, J. W.; Stockdon, H. F.

    2017-01-01

    Models of dune erosion depend on a set of assumptions that dictate the predicted evolution of dunes throughout the duration of a storm. Lidar observations made before and after Hurricane Sandy at over 800 profiles with diverse dune elevations, widths, and volumes are used to quantify specific dune erosion model parameters including the dune face slope, which controls dune avalanching, and the trajectory of the dune toe, which controls dune migration. Wave-impact models of dune erosion assume a vertical dune face and erosion of the dune toe along the foreshore beach slope. Observations presented here show that these assumptions are not always valid and require additional testing if these models are to be used to predict coastal vulnerability for decision-making purposes. Observed dune face slopes steepened by 43% yet did not become vertical faces, and only 50% of the dunes evolved along a trajectory similar to the foreshore beach slope. Observations also indicate that dune crests were lowered during dune erosion. Moreover, analysis showed a correspondence between dune lowering and narrower beaches, smaller dune volumes, and/or longer wave impact.

  12. Lizard assemblage from a sand dune habitat from southeastern Brazil: a niche overlap analysis.

    Science.gov (United States)

    Winck, Gisele R; Hatano, Fabio; Vrcibradic, Davor; VAN Sluys, Monique; Rocha, Carlos F D

    2016-01-01

    Communities are structured by interactions of historical and ecological factors, which influence the use of different resources in time and space. We acquired data on time of activity, microhabitat use and diet of a lizard assemblage from a sand dune habitat in a coastal area, southeastern Brazil (Restinga de Jurubatiba). We analyzed the data of niche overlap among species in these three axes (temporal, spatial and trophic) using null models. We found a significant overlap within the trophic niche, whereas the overlap for the other axes did not differ from the expected. Based on this result, we discuss the factors acting on the structure of the local lizard community.

  13. Primary sand-dune plant community and soil properties during the west-coast India monsoon

    Directory of Open Access Journals (Sweden)

    Willis A.

    2016-06-01

    Full Text Available A seven-station interrupted belt transect was established that followed a previously observed plant zonation pattern across an aggrading primary coastal dune system in the dry tropical region of west-coast India. The dominant weather pattern is monsoon from June to November, followed by hot and dry winter months when rainfall is scarce. Physical and chemical soil characteristics in each of the stations were analysed on five separate occasions, the first before the onset of monsoon, three during and the last post-monsoon. The plant community pattern was confirmed by quadrat survey. A pH gradient decreased with distance from the shoreline. Nutrient concentrations were deficient, increasing only in small amounts until the furthest station inland. At that location, there was a distinct and abrupt pedological transition zone from psammite to humic soils. There was a significant increase over previous stations in mean organic matter, ammonium nitrate and soil-water retention, although the increase in real terms was small. ANOVA showed significant variation in electrical conductivity, phosphorus, calcium, magnesium and sodium concentrations over time. There was no relationship between soil chemistry characteristics and plant community structure over the transect. Ipomoea pes-caprae and Spinifex littoreus were restricted to the foredunes, the leguminous forb Alysicarpus vaginalis and Perotis indica to the two stations furthest from the strand. Ischaemum indicum, a C4 perennial grass species adopting an ephemeral strategy was, in contrast, ubiquitous to all stations.

  14. Coastal dune facies, Permian Cutler Formation (White Rim Sandstone), Capitol Reef National Park area, southern Utah

    Science.gov (United States)

    Kamola, Diane L.; Chan, Marjorie A.

    1988-04-01

    The Permian Cutler Formation (White Rim Sandstone) in the Capitol Reef National Park area in southern Utah is an excellent example of a coastal dune complex subjected to periodic flooding by marine waters. Wind-ripple, grainfall and grainflow laminae compose the cross-sets deposited by eolian dunes. However, wave-reworked structures such as oscillation ripples, the occurrence of the characteristically marine trace fossils Thalassinoides and Chondrites, and interfingering marine carbonate beds of the Kaibab Formation collectively indicate marine interaction with the eolian environment. Four facies are distinguished: cross-stratified sandstone, burrowed to bioturbated sandstone, brecciated and deformed sandstone, and ripple-laminated sandstone and thin carbonate beds. One unusual aspect of the cross-stratified sandstone facies is the abundance of coarse-grained sand. Coarse-grained sand is atypical in many ancient eolian slipface deposits, but occurs here in large slipface foresets as both grainflow and wind-ripple deposits. No water-laid structures are found in these slipface deposits. Coarse-grained sand was probably transported to the Cutler shoreline by fluvial systems draining the Uncompahgre Uplift to the east, and then concentrated as coarse-grained ripples in interdune areas. Some of these coarse-grained ripples migrated up the stoss side of the dunes and accumulations of coarse-grained sand avalanched down the crest to form grainflow deposits. An extensive amount of soft-sediment deformation is indicated by the presence of convolute bedding and brecciation. These features occur near the zone of interfingering with marine carbonate beds of the Kaibab Formation. The water-saturated and moist conditions required for extensive deformation may have been controlled by the proximity of these sandstones to the shoreline, and fluctuations in the associated groundwater table.

  15. Developing Partnerships with the Community for Coastal ESD

    Science.gov (United States)

    Kawabe, Midori; Kohno, Hiroshi; Ikeda, Reiko; Ishimaru, Takashi; Baba, Osamu; Horimoto, Naho; Kanda, Jota; Matsuyam, Masaji; Moteki, Masato; Oshima, Yayoi; Sasaki, Tsuyoshi; Yap, Minlee

    2013-01-01

    Purpose: The purpose of this paper is to draw lessons for developing community-university partnerships from experiences in promoting coastal education for sustainable development (ESD). Design/methodology/approach: Qualitative data collected from two coastal community outreach projects were analyzed. Findings: The outreach projects improved the…

  16. Stratigraphy and landsnail faunas of Late Holocene coastal dunes, Tokerau Beach, northern New Zealand

    International Nuclear Information System (INIS)

    Brook, F.J.

    1999-01-01

    At least four depositional episodes, each involving cycles of dune instability and sand accumulation followed by stabilisation and soil formation, are represented in a Holocene dune sequence at Tokerau Beach. The first depositional episode followed the maximum post-glacial sea level rise at 6500 years BP, probably with formation of a narrow dune belt landward of the present coastline. The second depositional episode resulted in extensive progradation of the dune belt to about the present coastline from c. 3000-2000 years BP, followed by dune stabilisation and soil formation from c. 2000-900 years BP. The third depositional episode involved vertical dune accretion at c. 900-600 years BP, followed by stabilisation and soil formation after c. 600 years BP. The fourth depositional episode, after 240 years BP, resulted in further vertical dune accretion and localised extensive erosion and reworking of pre-existing dune deposits. Fossil landsnail faunas indicate that there was patchy sandfield and shrubland vegetation of the dune belt from c. 3000-2000 years BP, followed by a mosaic of shrubland and forest from c. 2000-900 years BP. After 900 years BP there was a progressive reversion to patchy shrubland vegetation, but an extensive shrubland cover again became established at c. 600 years BP and persisted until c. 450 years BP, when it was replaced by patchy shrubland and sandfield vegetation. Dune progradational phases in the first two depositional episodes correlate with and probably developed primarily in response to changes in sea level, whereas subsequent alternating phases of dune stabilisation and build-up are inferred to have resulted in part from the influence of long term cyclical variation in prevailing local wind and wave regimes in Doubtless Bay. Two stratigraphically distinct, exotic, sea-rafted pumice units are represented in the Tokerau dune sequence: Tokerau pumice (new), which has a primary depositional age of c. 3000 years BP, and Loisels pumice, which

  17. Sediment Source Fingerprinting of the Lake Urmia Sand Dunes.

    Science.gov (United States)

    Ahmady-Birgani, Hesam; Agahi, Edris; Ahmadi, Seyed Javad; Erfanian, Mahdi

    2018-01-09

    Aeolian sand dunes are continuously being discovered in inner dry lands and coastal areas, most of which have been formed over the Last Glacial Maximum. Presently, due to some natural and anthropogenic implications on earth, newly-born sand dunes are quickly emerging. Lake Urmia, the world's second largest permanent hypersaline lake, has started shrinking, vast lands comprising sand dunes over the western shore of the lake have appeared and one question has been playing on the minds of nearby dwellers: where are these sand dunes coming from, What there was not 15 years ago!! In the present study, the determination of the source of the Lake Urmia sand dunes in terms of the quantifying relative contribution of each upstream geomorphological/lithological unit has been performed using geochemical fingerprinting techniques. The findings demonstrate that the alluvial and the fluvial sediments of the western upstream catchment have been transported by water erosion and they accumulated in the lower reaches of the Kahriz River. Wind erosion, as a secondary agent, have carried the aeolian sand-sized sediments to the sand dune area. Hence, the Lake Urmia sand dunes have been originating from simultaneous and joint actions of alluvial, fluvial and aeolian processes.

  18. Stratigraphy, landsnail faunas, and paleoenvironmental history of Late Holocene coastal dunes, Tauroa Peninsula, northern New Zealand

    International Nuclear Information System (INIS)

    Brook, F.J.

    1999-01-01

    The post -700 years BP depositional history of the Holocene coastal dunebelt on northwestern Tauroa Peninsula involved an initial progradational phase, then a subsequent predominantly stable phase that began some time after 650 years BP, followed by a highly unstable phase from late prehistoric time to the present-day. Fossil landsnail faunas indicate that sandfield and prostrate shrubland have been the main vegetation types on the dunefield since at least 700 years BP, but that taller shrubland established locally during the later part of the prehistoric period of dunefield stability. Five species of landsnails became extinct on the dunefield in late prehistoric-historic time, probably as a result of vegetation disturbance caused by widespread dune mobilisation and erosion. (author). 19 refs., 3 figs., 1 tab

  19. Microbial Characterization of Qatari Barchan Sand Dunes.

    Directory of Open Access Journals (Sweden)

    Sara Abdul Majid

    Full Text Available This study represents the first characterization of sand microbiota in migrating barchan sand dunes. Bacterial communities were studied through direct counts and cultivation, as well as 16S rRNA gene and metagenomic sequence analysis to gain an understanding of microbial abundance, diversity, and potential metabolic capabilities. Direct on-grain cell counts gave an average of 5.3 ± 0.4 x 105 cells g-1 of sand. Cultured isolates (N = 64 selected for 16S rRNA gene sequencing belonged to the phyla Actinobacteria (58%, Firmicutes (27% and Proteobacteria (15%. Deep-sequencing of 16S rRNA gene amplicons from 18 dunes demonstrated a high relative abundance of Proteobacteria, particularly enteric bacteria, and a dune-specific-pattern of bacterial community composition that correlated with dune size. Shotgun metagenome sequences of two representative dunes were analyzed and found to have similar relative bacterial abundance, though the relative abundances of eukaryotic, viral and enterobacterial sequences were greater in sand from the dune closer to a camel-pen. Functional analysis revealed patterns similar to those observed in desert soils; however, the increased relative abundance of genes encoding sporulation and dormancy are consistent with the dune microbiome being well-adapted to the exceptionally hyper-arid Qatari desert.

  20. Wet dune slacks : decline and new opportunities

    NARCIS (Netherlands)

    Dijk, H.W.J. van; Grootjans, A.P.

    1993-01-01

    For a number of infiltrated coastal dune areas it is discussed to what extent artificial infiltration for the public water supply affects the quality of soil, groundwater and vegetation around pools and ponds, and what its effect is on the vegetation. Further, the results of investigations into the

  1. Modeling aeolian dune and dune field evolution

    Science.gov (United States)

    Diniega, Serina

    Aeolian sand dune morphologies and sizes are strongly connected to the environmental context and physical processes active since dune formation. As such, the patterns and measurable features found within dunes and dune fields can be interpreted as records of environmental conditions. Using mathematical models of dune and dune field evolution, it should be possible to quantitatively predict dune field dynamics from current conditions or to determine past field conditions based on present-day observations. In this dissertation, we focus on the construction and quantitative analysis of a continuum dune evolution model. We then apply this model towards interpretation of the formative history of terrestrial and martian dunes and dune fields. Our first aim is to identify the controls for the characteristic lengthscales seen in patterned dune fields. Variations in sand flux, binary dune interactions, and topography are evaluated with respect to evolution of individual dunes. Through the use of both quantitative and qualitative multiscale models, these results are then extended to determine the role such processes may play in (de)stabilization of the dune field. We find that sand flux variations and topography generally destabilize dune fields, while dune collisions can yield more similarly-sized dunes. We construct and apply a phenomenological macroscale dune evolution model to then quantitatively demonstrate how dune collisions cause a dune field to evolve into a set of uniformly-sized dunes. Our second goal is to investigate the influence of reversing winds and polar processes in relation to dune slope and morphology. Using numerical experiments, we investigate possible causes of distinctive morphologies seen in Antarctic and martian polar dunes. Finally, we discuss possible model extensions and needed observations that will enable the inclusion of more realistic physical environments in the dune and dune field evolution models. By elucidating the qualitative and

  2. Editorial - Special Issue on the Ninth International Conference on Aeolian Research - ICAR IX (Coastal Dune Processes and Aeolian Transport)

    Science.gov (United States)

    da Silva, Graziela Miot

    2018-04-01

    This special issue combines some of the papers related to coastal dune processes and aeolian sediment transport that were presented at the Ninth International Conference on Aeolian Research - ICAR IX. The conference was held between 4 and 8 of July 2016 in Mildura, Australia, organized by the International Society for Aeolian Research (ISAR) and convened by Adrian Chappell (Cardiff University), Craig Strong (Australian National University), Stephen Cattle (University of Sydney), Patrick Hesp (Flinders University), John Leys (New South Wales Office of Environment and Heritage), Lynda Petherick (University of Wellington) and Nick Webb (USDA-ARS Jornada Experimental Range).

  3. Lizard assemblage from a sand dune habitat from southeastern Brazil: a niche overlap analysis

    Directory of Open Access Journals (Sweden)

    GISELE R. WINCK

    2016-01-01

    Full Text Available ABSTRACT Communities are structured by interactions of historical and ecological factors, which influence the use of different resources in time and space. We acquired data on time of activity, microhabitat use and diet of a lizard assemblage from a sand dune habitat in a coastal area, southeastern Brazil (Restinga de Jurubatiba. We analyzed the data of niche overlap among species in these three axes (temporal, spatial and trophic using null models. We found a significant overlap within the trophic niche, whereas the overlap for the other axes did not differ from the expected. Based on this result, we discuss the factors acting on the structure of the local lizard community.

  4. Coastal Community Group for Coastal Resilient in Timbulsloko Village, Sayung, Demak Regency, Indonesia

    Science.gov (United States)

    Purnaweni, Hartuti; Kismartini; Hadi, Sudharto P.; Soraya, Ike

    2018-02-01

    Coastal areas are very dynamic and fragile environment, demanding for policies to preserve these areas as materialized in the Resilient Coastal Development Program (PKPT) by the Indonesian government. Amongst the targeted area was Timbulsloko Village in Sayung District, Demak Regency, which coastal areas is severely damaged by erosion. This article analyzed the development of the Coastal Community Group (CCG) related to the PKPT program in Timbulsloko village, especially in how the group is empowered to increase the community's resilient in facing the disaster. This study, applied an analytical descriptive method, used the development of the CCG as phenomenon. Primary data was collected through observation and in-depth interviews with stakeholders, accompanying the secondary data. The result shows that the PKPT funding was mostly spent on infrastructure development and used for project management, not for optimizing local economic empowerment. After the completion of the PKPT, there are no actions or following programs to keep the physical results constructed by the CCG. Accordingly, the orientation towards the CCG building capacity for Timbulsloko community's ecological resilience had not been optimally implemented. This study recommended a "putting the last first" policy approach to preparing the local community. The government must play a stronger role in encouraging a self-help local group for strong human development

  5. Ecogeomorphology of Sand Dunes Shaped by Vegetation

    Science.gov (United States)

    Tsoar, H.

    2014-12-01

    Two dune types associated with vegetation are known: Parabolic and Vegetated Linear Dunes (VLDs), the latters are the dominant dune type in the world deserts. Parabolic dunes are formed in humid, sub-humid and semi-arid environments (rather than arid) where vegetation is nearby. VLDs are known today in semiarid and arid lands where the average yearly rainfall is ≥100 mm, enough to support sparse cover of vegetation. These two dune types are formed by unidirectional winds although they demonstrate a different form and have a distinct dynamics. Conceptual and mathematical models of dunes mobility and stability, based on three control parameters: wind power (DP), average annual precipitation (p), and the human impact parameter (μ) show that where human impact is negligible the effect of wind power (DP) on vegetative cover is substantial. The average yearly rainfall of 60-80 mm is the threshold of annual average rainfall for vegetation growth on dune sand. The model is shown to follow a hysteresis path, which explains the bistability of active and stabilized dunes under the same climatic conditions with respect to wind power. We have discerned formation of parabolic dunes from barchans and transverse dunes in the coastal plain of Israel where a decrease in human activity during the second half of the 20th century caused establishment of vegetation on the crest of the dunes, a process that changed the dynamics of these barchans and transverse dunes and led to a change in the shape of the windward slope from convex to concave. These dunes gradually became parabolic. It seems that VLDs in Australia or the Kalahari have always been vegetated to some degree, though the shrubs were sparser in colder periods when the aeolian erosion was sizeable. Those ancient conditions are characterized by higher wind power and lower rainfall that can reduce, but not completely destroy, the vegetation cover, leading to the formation of lee (shadow) dunes behind each shrub. Formation of

  6. Dune advance into a coastal forest, equatorial Brazil: A subsurface perspective

    Science.gov (United States)

    Buynevich, Ilya V.; Filho, Pedro Walfir M. Souza; Asp, Nils E.

    2010-06-01

    A large active parabolic dune along the coast of Pará State, northern Brazil, was analyzed using aerial photography and imaged with high-resolution ground-penetrating radar (GPR) to map the subsurface facies architecture and point-source anomalies. Most high-amplitude (8-10 dB) subsurface anomalies are correlated with partially buried mangrove trees along the leading edge (slipface) of the advancing dune. Profiles along a 200-m long basal stoss side of the dune reveal 66 targets, most of which lie below the water table and are thus inaccessible by other methods. Signal amplitudes of point-source anomalies are substantially higher than those associated with the reflections from continuous subsurface features (water table, sedimentary layers). When complemented with exposures and excavations, GPR provides the best means of rapid continuous imaging of the geological record of complex interactions between vegetation and aeolian deposition.

  7. An evolving research agenda for human-coastal systems

    Science.gov (United States)

    Lazarus, Eli D.; Ellis, Michael A.; Brad Murray, A.; Hall, Damon M.

    2016-03-01

    Within the broad discourses of environmental change, sustainability science, and anthropogenic Earth-surface systems, a focused body of work involves the coupled economic and physical dynamics of developed shorelines. Rapid rates of change in coastal environments, from wetlands and deltas to inlets and dune systems, help researchers recognize, observe, and investigate coupling in natural (non-human) morphodynamics and biomorphodynamics. This same intrinsic quality of fast-paced change also makes developed coastal zones exemplars of observable coupling between physical processes and human activities. In many coastal communities, beach erosion is a natural hazard with economic costs that coastal management counters through a variety of mitigation strategies, including beach replenishment, groynes, revetments, and seawalls. As cycles of erosion and mitigation iterate, coastline change and economically driven interventions become mutually linked. Emergent dynamics of two-way economic-physical coupling is a recent research discovery. Having established a strong theoretical basis, research into coupled human-coastal systems has passed its early proof-of-concept phase. This paper frames three major challenges that need resolving in order to advance theoretical and empirical treatments of human-coastal systems: (1) codifying salient individual and social behaviors of decision-making in ways that capture societal actions across a range of scales (thus engaging economics, social science, and policy disciplines); (2) quantifying anthropogenic effects on alongshore and cross-shore sediment pathways and long-term landscape evolution in coastal zones through time, including direct measurement of cumulative changes to sediment cells resulting from coastal development and management practices (e.g., construction of buildings and artificial dunes, bulldozer removal of overwash after major storms); and (3) reciprocal knowledge and data exchange between researchers in coastal

  8. Integrated Community Based Coastal Management: Lesson From The Field

    Science.gov (United States)

    Hadi, Sudharto P.

    2018-02-01

    Coastal abrasion has been occurred throughout coastline of Java reaching 745 km at length, account for 44% of total Java’s coastline. This phenomena is caused by reclamation, cutting of mangrove, land-use change and other human activities specifically at coastal area. Coastal abrasion stimulates flood or tidal flood, when sea level rise, the sea water flows to the land undated fish pond, settlement and other infrastructures standing at coastal area. Tidal flood destroys settlement lead to significant decrease of property value: land and house. Coastal abrasion caused lose people’s job and income. One measure taken by local community is mangrove cultivation intended to prevent sea level rise flowing to the inland. However many efforts taken by community frequently fail because of un-integrated approach. This paper reviews a mangrove plantations in Mangunharjo, district of Tugu, Semarang, Central Java by utilizing an innovative approach integrating environmental, economic and social aspect. These mangrove cultivations environmentally useful to prevent coastal abrasion, economically creating income for local people and socially supported by local community. These three approaches ensure sustainability of mangrove’s culture.

  9. Engaging Communities Where They Are: New Hampshire's Coastal Adaptation Workgroup

    Science.gov (United States)

    Wake, C. P.; Godlewski, S.; Howard, K.; Labranche, J.; Miller, S.; Peterson, J.; Ashcraft, C.

    2015-12-01

    Rising seas are expected to have significant impacts on infrastructure and natural and cultural resources on New Hampshire's 18 mile open-ocean coastline and 235 miles of tidal shoreline. However, most coastal municipalities in NH lack financial and human resources to even assess vulnerability, let alone plan for climate change. This gap has been filled since 2010 by the NH Coastal Adaptation Workgroup (CAW), composed of 21 regional, state, and federal agencies, businesses, municipalities, academics, and NGOs that bring together stakeholders to discuss climate change challenges and collaboratively develop and implement effective coastal adaptation strategies. Our grassroot efforts serve to nurture existing and build new relationships, disseminate coastal watershed climate assessments, and tap into state, federal, and foundation funds for specific coastal adaptation projects. CAW has achieved collective impact in by connecting federal and state resources to communities by raising money and facilitating projects, translating climate science, educating community members, providing direct technical assistance and general capacity, and sharing success stories and lessons learned. Indicators of success include: 12 coastal communities improved their technical, financial, and human resources for climate adaptation; 80% of the 300 participants in the eleven CAW 'Water, Weather, Climate, and Community Workshops' have increased knowledge, motivation, and capacity to address climate adaptation; $3 million in grants to help communities with climate adaptation; winner of the 2015 EPA Region 1 Environmental Merit Award; and ongoing support for community-led adaptation efforts. In addition, the NH Climate Summit attracts over 100 participants each year, over 90% whom attest to the applicability of what they learn there. CAW also plays a central role in the Coastal Risks and Hazards Commission (established by the state legislature in 2013) to help communities and businesses prepare

  10. Endophytic fungi associated with roots of date palm (Phoenix dactylifera) in coastal dunes.

    Science.gov (United States)

    Mohamed Mahmoud, Fadila; Krimi, Zoulikha; Maciá-Vicente, Jose G; Brahim Errahmani, Mohamed; Lopez-Llorca, Luis V

    Symbiotic interactions with fungal endophytes are argued to be responsible for the tolerance of plants to some stresses and for their adaptation to natural conditions. In this study we aimed to examine the endophytic fungal diversity associated with roots of date palms growing in coastal dune systems, and to screen this collection of endophytes for potential use as biocontrol agents, for antagonistic activity and mycoparasitism, and as producers of antifungal compounds with potential efficacy against root diseases of date palm. Roots of nine individual date palms growing in three coastal locations in the South-East of Spain (Guardamar, El Carabassí, and San Juan) were selected to isolate endophytic fungi. Isolates were identified on the basis of morphological and/or molecular characters. Five hundred and fifty two endophytic fungi were isolated and assigned to thirty morphological taxa or molecular operational taxonomic units. Most isolates belonged to Ascomycota, and the dominant order was Hypocreales. Fusarium and Clonostachys were the most frequently isolated genera and were present at all sampling sites. Comparisons of the endophytic diversity with previous studies, and their importance in the management of the date palm crops are discussed. This is the first study on the diversity of endophytic fungi associated with roots of date palm. The isolates obtained might constitute a source of biological control agents and biofertilizers for use in crops of this plant. Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

  11. A whole plant approach to evaluate the water use of mediterranean maquis species in a coastal dune ecosystem

    Science.gov (United States)

    Mereu, S.; Salvatori, E.; Fusaro, L.; Gerosa, G.; Muys, B.; Manes, F.

    2009-02-01

    An integrated approach has been used to analyse the water relations of three Mediterranean species, A. unedo L., Q. ilex L. and P. latifolia L. co-occurring in a coastal dune ecosystem. The approach considered leaf level gas exchange, sap flow measurements and structural adaptations between 15 May and 31 July 2007, and was necessary to capture the different response of the three species to the same environment. The complexity of the response was proportional to the complexity of the system, characterized by a sandy soil with a low water retention capacity and the presence of a water table. The latter did not completely prevent the development of a drought response, and species differences in this responses have been partially attributed to a different root distribution. Sap flow of A. unedo decreased rapidly in response to the decline of Soil Water Content, while that of Q. ilex decreased only moderately. Midday leaf water potential of P. latifolia and A. unedo was between 2.2 and 2.7 MPa through the measuring period, while in Q. ilex it reached a value of 3.4 MPa at the end of the season. A. unedo was the only species to decrease the leaf area to sapwood area ratio from 23.9±1.2 (May) to 15.2±1.5 (July), as a response to drought. A. unedo also underwent an almost stepwise loss on hydraulic conductivity, such a loss didn't occur for Q. ilex, while P. latifolia was able to slightly increase hydraulic conductivity, showing how different plant compartments coordinate differently between species as a response to drought. Such different coordination affects the gas exchange between vegetation and the atmosphere, and has implications for the response of the Mediterranean coastal dune ecosystems to climate change.

  12. Nitrogen deposition and grass encroachment in calcareous and acidic Grey dunes (H2130) in NW-Europe

    NARCIS (Netherlands)

    Kooijman, A.M.; van Til, M.; Noordijk, E.; Remke, E.; Kalbitz, K.

    We present an overview of high nitrogen deposition effects on coastal dune grasslands in NW-Europe (H2130), especially concerning grass encroachment in calcareous and acidic Grey Dunes. The problem is larger than previously assumed, because critical loads are still too high, and extra N-input from

  13. Adaptation Decision Support: An Application of System Dynamics Modeling in Coastal Communities

    Institute of Scientific and Technical Information of China (English)

    Daniel Lane; Shima Beigzadeh; Richard Moll

    2017-01-01

    This research develops and applies a system dynamics (SD) model for the strategic evaluation of environmental adaptation options for coastal communities.The article defines and estimates asset-based measures for community vulnerability,resilience,and adaptive capacity with respect to the environmental,economic,social,and cultural pillars of the coastal community under threat.The SD model simulates the annual multidimensional dynamic impacts of severe coastal storms and storm surges on the community pillars under alternative adaptation strategies.The calculation of the quantitative measures provides valuable information for decision makers for evaluating the alternative strategies.The adaptation strategies are designed model results illustrated for the specific context of the coastal community of Charlottetown,Prince Edward Island,Canada.The dynamic trend of the measures and model sensitivity analyses for Charlottetown-facing increased frequency of severe storms,storm surges,and sea-level rise-provide impetus for enhanced community strategic planning for the changing coastal environment.This research is presented as part of the International Community-University Research Alliance C-Change project "Managing Adaptation to Environmental Change in Coastal Communities:Canada and the Caribbean" sponsored by the Social Science and Humanities Research Council of Canada and the International Development Resource Centre.

  14. Erosion reasons and rate on accumulative Polish dune coast caused by the January 2012 storm surge

    Directory of Open Access Journals (Sweden)

    Tomasz A. Łabuz

    2014-03-01

    Full Text Available The Polish coast is a non-tidal area; its shores are affected mainly by autumn-winter storm surges. Those of 6 and 14 January 2012 are representative of the forces driving the erosion of normally accumulative sections of coastal dunes, monitored by the author since 1997. The sea level maximum during these two storm surges reached 1.2 to 1.5 m amsl along the Polish coast. Land forms up to 3 m amsl were inundated. Beaches and low parts of the coast up to this height were rebuilt by sea waves attacking the coast for almost 12 days. Quantitative analyses of the morphological dynamics of the coastal dunes are presented for 57 profiles located along the coast. Only those accumulative sections of the Polish coast are analysed where sand accumulation did occur and led to new foredune development. The mean rate of dune erosion was 2.5 m3 per square metre with an average toe retreat of 1.4 m. Erosion understood as dune retreat was greater when a beach was lower (correlation coefficient 0.8. Dune erosion did not occur on coasts with beaches higher than 3.2 m or on lower ones covered by embryo dunes.

  15. Library Development Strategy for The Community at Coastal Areas

    Science.gov (United States)

    Suharso, Putut; Sudardi, Bani; Teguh Widodo, Sahid; Kusumo Habsari, Sri

    2018-02-01

    This study aims to reveal various phenomena of the existence of libraries in coastal areas, especially to pay a particular attention to the relation power between various interests of the library, especially the managers and the community as the users and to explore how both parties understand and imagine the idea of library through the developing the library as a center of learning and skill development. The design of the research is explorative qualitative. Applying case study approach, the location of this research is in a coastal area, in the floating library of Tambak Lorok coastal, Semarang. Data are collected through observation and in-depth interviews with several parties involved. To examine the validity of data, this study applies a triangulation technique of sources focusing on key informants living in the community. The result of this research shows that the existence of library in the coastal area is more than the common belief to the function of library. Although finding shows that the government’s attitude to support the development of the library has been as expected through producing some regulations, the response of the community to the development of the library is far beyond the expectation. Some drawbacks found are in the handling of library management which is still lack of implementation from the initial planning and the absence of integrated coastal resources management resulted from low understanding and mastery of policy makers and implementers of the national library program. However, the community has developed a community-based management which is an approach that has been widely used in various regions as an effort to empower themselves through utilizing any existed facilities, in this case is the library. Community has successfully produced an initiative of developing integrated coastal resource management programs which are still hard to find in Indonesia, especially those involving library institutions.

  16. Community management of coastal resources, southern Thailand

    OpenAIRE

    Chansnoh, P.

    1993-01-01

    The involvement of communities with the assistance and support of government and non government organizations on the management of the coastal resources in Southern Thailand are discussed. The 3 most important resources, mangrove, seagrass and coral, create a complex coastal ecology. Several man-made activities causing the deterioration of this resources are also presented.

  17. Empowerment and Coastal Community Participation on Mangrove Development in Pati Regency

    Directory of Open Access Journals (Sweden)

    Sutrisno

    2015-03-01

    Full Text Available Development of mangrove plants is a very complex effort to implement, because the activity needs accommodative nature of the community around the coastal. This study aims to determine the government's role in the empowerment of coastal communities and public participation in the development of coastal mangrove plant in Pati regency. The research used descriptive approach with primary data was obtained from survey toward 282 respondents whom directly involved in mangrove development, while secondary data were obtained from relevant documents. The data were analyzed using descriptive method. The results of research are: (1 The score of government’s role on coastal community empowerment and mangrove development is 49.94 (categorized as enough. (2 Community empowerment on mangrove development get score 41.81 (categorized as enough.

  18. Strengthening threatened communities through adaptation: insights from coastal Mozambique

    Directory of Open Access Journals (Sweden)

    Jessica L. Blythe

    2014-06-01

    Full Text Available Change is a defining characteristic of coastal social-ecological systems, yet the magnitude and speed of contemporary change is challenging the adaptive capacity of even the most robust coastal communities. In the context of multiple drivers of change, it has become increasingly important to identify how threatened communities adapt to livelihood stressors. We investigate how adaptation is negotiated in two coastal fishing communities by documenting livelihood stressors, household assets, adaptive strategies, and factors that facilitate or inhibit adaptation. Declining catch is the most common stressor being experienced in both communities, however, socioeconomic, e.g., disease or theft, and ecological, e.g., severe storms and drought, changes are also creating livelihood stress. We find that specialized fishers' with higher investment in fishing gear and government support are adapting by intensifying their fishing efforts, whereas poorer fishers with more livelihood options are adapting through diversification. Adaptation is facilitated by fishers' groups, occupational pride, and family networks. It is inhibited by limited assets, competition over declining resources, and pervasive poverty. Our data suggest that adaptation is a heterogeneous process that is influenced by multiple factors. Understanding the complexity of fishers' responses to livelihood stressors is critical for fostering adaptive capacity in coastal communities, for strengthening fisheries management, and for improving the livelihoods of fishing dependent communities.

  19. Assessing radiation impact at a protected coastal sand dune site: an intercomparison of models for estimating the radiological exposure of non-human biota

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Michael D., E-mail: mwood@liv.ac.u [Institute for Sustainable Water Integrated Management and Ecosystem Research (SWIMMER), Nicholson Building, University of Liverpool, Liverpool, Merseyside L69 3GP (United Kingdom); School of Biological Sciences, Nicholson Building, University of Liverpool, Liverpool, Merseyside L69 3GP (United Kingdom); Beresford, Nicholas A.; Barnett, Catherine L. [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster, Lancashire LA1 4AP (United Kingdom); Copplestone, David [Environment Agency, PO Box 12, Richard Fairclough House, Knutsford Road, Latchford, Warrington, Cheshire WA4 1HG (United Kingdom); Leah, Richard T. [Institute for Sustainable Water Integrated Management and Ecosystem Research (SWIMMER), Nicholson Building, University of Liverpool, Liverpool, Merseyside L69 3GP (United Kingdom); School of Biological Sciences, Nicholson Building, University of Liverpool, Liverpool, Merseyside L69 3GP (United Kingdom)

    2009-12-15

    This paper presents the application of three publicly available biota dose assessment models (the ERICA Tool, R and D128/SP1a and RESRAD-BIOTA) to an assessment of the Drigg coastal sand dunes. Using measured {sup 90}Sr, {sup 99}Tc, {sup 137}Cs, {sup 238}Pu, {sup 239+240}Pu and {sup 241}Am activity concentrations in sand dune soil, activity concentration and dose rate predictions are made for a range of organisms including amphibians, birds, invertebrates, mammals, reptiles, plants and fungi. Predicted biota activity concentrations are compared to measured data where available. The main source of variability in the model predictions is the transfer parameters used and it is concluded that developing the available transfer databases should be a focus of future research effort. The value of taking an informed user approach to investigate the way in which models may be expected to be applied in practice is highlighted and a strategy for the future development of intercomparison exercises is presented.

  20. Assessing radiation impact at a protected coastal sand dune site: an intercomparison of models for estimating the radiological exposure of non-human biota

    International Nuclear Information System (INIS)

    Wood, Michael D.; Beresford, Nicholas A.; Barnett, Catherine L.; Copplestone, David; Leah, Richard T.

    2009-01-01

    This paper presents the application of three publicly available biota dose assessment models (the ERICA Tool, R and D128/SP1a and RESRAD-BIOTA) to an assessment of the Drigg coastal sand dunes. Using measured 90 Sr, 99 Tc, 137 Cs, 238 Pu, 239+240 Pu and 241 Am activity concentrations in sand dune soil, activity concentration and dose rate predictions are made for a range of organisms including amphibians, birds, invertebrates, mammals, reptiles, plants and fungi. Predicted biota activity concentrations are compared to measured data where available. The main source of variability in the model predictions is the transfer parameters used and it is concluded that developing the available transfer databases should be a focus of future research effort. The value of taking an informed user approach to investigate the way in which models may be expected to be applied in practice is highlighted and a strategy for the future development of intercomparison exercises is presented.

  1. Hurricane Ike: Observations and Analysis of Coastal Change

    Science.gov (United States)

    Doran, Kara S.; Plant, Nathaniel G.; Stockdon, Hilary F.; Sallenger, Asbury H.; Serafin, Katherine A.

    2009-01-01

    Understanding storm-induced coastal change and forecasting these changes require knowledge of the physical processes associated with the storm and the geomorphology of the impacted coastline. The primary physical processes of interest are the wind field, storm surge, and wave climate. Not only does wind cause direct damage to structures along the coast, but it is ultimately responsible for much of the energy that is transferred to the ocean and expressed as storm surge, mean currents, and large waves. Waves and currents are the processes most responsible for moving sediments in the coastal zone during extreme storm events. Storm surge, the rise in water level due to the wind, barometric pressure, and other factors, allows both waves and currents to attack parts of the coast not normally exposed to those processes. Coastal geomorphology, including shapes of the shoreline, beaches, and dunes, is equally important to the coastal change observed during extreme storm events. Relevant geomorphic variables include sand dune elevation, beach width, shoreline position, sediment grain size, and foreshore beach slope. These variables, in addition to hydrodynamic processes, can be used to predict coastal vulnerability to storms The U.S. Geological Survey's (USGS) National Assessment of Coastal Change Hazards Project (http://coastal.er.usgs.gov/hurricanes), strives to provide hazard information to those interested in the Nation's coastlines, including residents of coastal areas, government agencies responsible for coastal management, and coastal researchers. As part of the National Assessment, observations were collected to measure coastal changes associated with Hurricane Ike, which made landfall near Galveston, Texas, on September 13, 2008. Methods of observation included aerial photography and airborne topographic surveys. This report documents these data-collection efforts and presents qualitative and quantitative descriptions of hurricane-induced changes to the shoreline

  2. Long-term impacts of nitrogen deposition on coastal plant communities

    DEFF Research Database (Denmark)

    Pakeman, Robin J.; Brooker, Rob; Alexander, Jim

    2016-01-01

    , Fixed dune, Heath, Slack and Tall grass mire communities and despite falls in EIV-N for Improved grass, Strand and Wet grassland. The increase in EIV-N was highly correlated to the cumulative deposition between the surveys, and for sites in south-east Scotland, eutrophication impacts appear severe...

  3. The influence of groundwater depth on coastal dune development at sand flats close to inlets

    Science.gov (United States)

    Silva, Filipe Galiforni; Wijnberg, Kathelijne M.; de Groot, Alma V.; Hulscher, Suzanne J. M. H.

    2018-05-01

    A cellular automata model is used to analyze the effects of groundwater levels and sediment supply on aeolian dune development occurring on sand flats close to inlets. The model considers, in a schematized and probabilistic way, aeolian transport processes, groundwater influence, vegetation development, and combined effects of waves and tides that can both erode and accrete the sand flat. Next to three idealized cases, a sand flat adjoining the barrier island of Texel, the Netherlands, was chosen as a case study. Elevation data from 18 annual LIDAR surveys was used to characterize sand flat and dune development. Additionally, a field survey was carried out to map the spatial variation in capillary fringe depth across the sand flat. Results show that for high groundwater situations, sediment supply became limited inducing formation of Coppice-like dunes, even though aeolian losses were regularly replenished by marine import during sand flat flooding. Long dune rows developed for high sediment supply scenarios which occurred for deep groundwater levels. Furthermore, a threshold depth appears to exist at which the groundwater level starts to affect dune development on the inlet sand flat. The threshold can vary spatially depending on external conditions such as topography. On sand flats close to inlets, groundwater is capable of introducing spatial variability in dune growth, which is consistent with dune development patterns found on the Texel sand flat.

  4. Variability and correlations of shoreline and dunes on the southern Baltic coast (CRS Lubiatowo, Poland)

    OpenAIRE

    Zbigniew Pruszak; Rafal Ostrowski; Jan Schönhofer

    2011-01-01

    The paper analyses the results of field investigations into the evolution of the shoreline and dune toe positions in a multi-bar,dissipative coastal zone. The correlations between the changes in the shoreline and the dune toe range from -0.4 to 0.8. It is most often the case that the dune toe is stable while the shoreline moves. Consistent cross-shore migration is slightly more likelyto happen than the divergent or convergent movements of both lines. Shoreline retreat and advance attain resp...

  5. RPAS Monitoring of the Morphological Evolution of Coastal Foredunes

    Science.gov (United States)

    Taddia, Yuri; Corbau, Corinne; Elena, Zambello; Russo, Valentina; Pellegrinelli, Alberto; Simeoni, Umberto

    2016-04-01

    The coastal environment is in rapid and continuous evolution and it is easily affected by many natural and antropic factors. Beaches are often backed by vegetated dunes and fulfill many different valuable ecosystem functions. They act as protective buffers against storm surge, wave attack and erosion, providing a unique habitat for flora and fauna. Coastal embryo dunes, found above mean high water, are dynamic landform being able to supply sand to the beach when needed. They may form rapidly and may be rapidly destructed due to high tides and storm waves or human interferences. The southern part (3 km long) of Rosolina (Adriatic Sea, Italy) is characterized by a wide beach bordered by a complex dune system. The geomorphological characteristics of embryo dunes have been identified by using an RPAS in order to develop a fast and low-cost surveying technique. The aircraft has flown at a 50 meters altitude, taking photos with a 12Mpix RGB camera and a GSD of about 1 cm. The images overlap of 80% in the flight direction and 60% laterally. Fourteen targets have been collocated in the area as ground control points and were surveyed using Network Real Time Kinematic (NRTK) GNSS. Images and GCPs were elaborated in Agisoft PhotoScan to generate the model. A similar NRTK survey has been performed to integrate the wrong data (due to vegetation) for the creation of a digital elevation model (DEM) in a first step and finally to validate the model obtained through UAV photogrammetry through a comparison with specially surveyed points. The creation of a DEM from photos is one of main tasks and its accuracy is critical. A challenge in this work was to recognize the vegetation in the sand dunes area to exclude all the points not belonging to the ground. This was possible through a classification process based on slope detection. Finally, the suitable elevation accuracy has been reached and the survey has revealed a complex dune system characterized by: • on the upper part of the

  6. Erosion and its rate on an accumulative Polish dune coast: the effects of the January 2012 storm surge

    Directory of Open Access Journals (Sweden)

    Tomasz A. Łabuz

    2014-01-01

    Full Text Available The Polish coast is a non-tidal area; its shores are affected mainly by autumn-winter storm surges. Those of 6 and 14 January 2012 are representative of the forces driving the erosion of normally accumulative sections of coastal dunes, monitored by the author since 1997. The sea level maximum during these two storm surges reached 1.2 to 1.5 m amsl along the Polish coast. Land forms up to 3 m amsl were inundated. Beaches and low parts of the coast up to this height were rebuilt by sea waves attacking the coast for almost 12 days. Quantitative analyses of the morphological dynamics of the coastal dunes are presented for 57 profiles located along the coast. Only those accumulative sections of the Polish coast are analysed where sand accumulation did occur and led to new foredune development. The mean rate of dune erosion was 2.5 m3 per square metre with an average toe retreat of 1.4 m. Erosion understood as dune retreat was greater when a beach was lower (correlation coefficient 0.8. Dune erosion did not occur on coasts with beaches higher than 3.2 m or on lower ones covered by embryo dunes.

  7. Resource-Based Capability on Development Knowledge Management Capabilities of Coastal Community

    Science.gov (United States)

    Teniwut, Roberto M. K.; Hasyim, Cawalinya L.; Teniwut, Wellem A.

    2017-10-01

    Building sustainable knowledge management capabilities in the coastal area might face a whole new challenge since there are many intangible factors involved from openness on new knowledge, access and ability to use the latest technology to the various local wisdom that still in place. The aimed of this study was to identify and analyze the resource-based condition of coastal community in this area to have an empirical condition of tangible and intangible infrastructure on developing knowledge management capability coastal community in Southeast Maluku, Indonesia. We used qualitative and quantitative analysis by depth interview and questionnaire for collecting the data with multiple linear regression as our analysis method. The result provided the information on current state of resource-based capability of a coastal community in this Southeast Maluku to build a sustainability model of knowledge management capabilities especially on utilization marine and fisheries resources. The implication of this study can provide an empirical information for government, NGO and research institution to dictate on how they conducted their policy and program on developing coastal community region.

  8. Does salt stress constrain spatial distribution of dune building grasses Ammophila arenaria and Elytrichia juncea on the beach?

    Science.gov (United States)

    van Puijenbroek, Marinka E B; Teichmann, Corry; Meijdam, Noortje; Oliveras, Imma; Berendse, Frank; Limpens, Juul

    2017-09-01

    Rising sea levels threaten coastal safety by increasing the risk of flooding. Coastal dunes provide a natural form of coastal protection. Understanding drivers that constrain early development of dunes is necessary to assess whether dune development may keep pace with sea-level rise. In this study, we explored to what extent salt stress experienced by dune building plant species constrains their spatial distribution at the Dutch sandy coast. We conducted a field transplantation experiment and a glasshouse experiment with two dune building grasses Ammophila arenaria and Elytrigia juncea . In the field, we measured salinity and monitored growth of transplanted grasses in four vegetation zones: (I) nonvegetated beach, (II) E. juncea occurring, (III) both species co-occurring, and (IV) A. arenaria dominant. In the glasshouse, we subjected the two species to six soil salinity treatments, with and without salt spray. We monitored biomass, photosynthesis, leaf sodium, and nutrient concentrations over a growing season. The vegetation zones were weakly associated with summer soil salinity; zone I and II were significantly more saline than zones III and IV. Ammophila arenaria performed equally (zone II) or better (zones III, IV) than E. juncea , suggesting soil salinity did not limit species performance. Both species showed severe winter mortality. In the glasshouse, A. arenaria biomass decreased linearly with soil salinity, presumably as a result of osmotic stress. Elytrigia juncea showed a nonlinear response to soil salinity with an optimum at 0.75% soil salinity. Our findings suggest that soil salinity stress either takes place in winter, or that development of vegetated dunes is less sensitive to soil salinity than hitherto expected.

  9. COASTAL COMMUNITY PARTICIPATION IN KELURAHAN SUKOLILO, BULAK, BASED ON LOCAL ECONOMY

    Directory of Open Access Journals (Sweden)

    Dyah Kusuma Wardhani

    2017-07-01

    Full Text Available Kelurahan Sukolilo, Bulak Settlement is an area of fishermen settlement with great potential of resources such as fish and sea cucumber. Kelurahan Sukolilo also well known as Prominent Kampung in fish processed products. Despite having a great potential in marine resources, most of the fishermen still live in a low environmental and economic condition. Theres hould be effective environmental management in coastal area so the fiherman vulnerability can be reduced through a criteria of developing coastal area that is able to accomodate the fisherman economic activities. The researcher will apply community based development in developing coastal area criteria.. In this case community-based development approach needs to be developed in the management of coastal areas, especially for the improvement of the environmental quality. This is because the coastal characteristic and resources are very complex and diverse, so in the coastal area management should involve the local community directly. Community based management shows the importance of community participation in development planning and implementation. This research was in form of qualitative research, data sources obtained by primary and secondary data. Primary data were collected through observations, visual documentations and interview with the fishermen and fish processors. Secondary data were obtained from literature and theory. Research results showed that  level of community participation that need to be done in the development process using active participatory. Active participatory should be done through partnership and delegated power level to accomodate fishermen and fish processors activities and support sustainable environment. Co-working space for inhabitants is needed  to accomodate community activities related to water and odor and drying process and to create area to socialize

  10. Uavs to Assess the Evolution of Embryo Dunes

    Science.gov (United States)

    Taddia, Y.; Corbau, C.; Zambello, E.; Russo, V.; Simeoni, U.; Russo, P.; Pellegrinelli, A.

    2017-08-01

    The balance of a coastal environment is particularly complex: the continuous formation of dunes, their destruction as a result of violent storms, the growth of vegetation and the consequent growth of the dunes themselves are phenomena that significantly affect this balance. This work presents an approach to the long-term monitoring of a complex dune system by means of Unmanned Aerial Vehicles (UAVs). Four different surveys were carried out between November 2015 and November 2016. Aerial photogrammetric data were acquired during flights by a DJI Phantom 2 and a DJI Phantom 3 with cameras in a nadiral arrangement. GNSS receivers in Network Real Time Kinematic (NRTK) mode were used to frame models in the European Terrestrial Reference System. Processing of the captured images consisted in reconstruction of a three-dimensional model using the principles of Structure from Motion (SfM). Particular care was necessary due to the vegetation: filtering of the dense cloud, mainly based on slope detection, was performed to minimize this issue. Final products of the SfM approach were represented by Digital Elevation Models (DEMs) of the sandy coastal environment. Each model was validated by comparison through specially surveyed points. Other analyses were also performed, such as cross sections and computing elevation variations over time. The use of digital photogrammetry by UAVs is particularly reliable: fast acquisition of the images, reconstruction of high-density point clouds, high resolution of final elevation models, as well as flexibility, low cost and accuracy comparable with other available techniques.

  11. UAVS TO ASSESS THE EVOLUTION OF EMBRYO DUNES

    Directory of Open Access Journals (Sweden)

    Y. Taddia

    2017-08-01

    Full Text Available The balance of a coastal environment is particularly complex: the continuous formation of dunes, their destruction as a result of violent storms, the growth of vegetation and the consequent growth of the dunes themselves are phenomena that significantly affect this balance. This work presents an approach to the long-term monitoring of a complex dune system by means of Unmanned Aerial Vehicles (UAVs. Four different surveys were carried out between November 2015 and November 2016. Aerial photogrammetric data were acquired during flights by a DJI Phantom 2 and a DJI Phantom 3 with cameras in a nadiral arrangement. GNSS receivers in Network Real Time Kinematic (NRTK mode were used to frame models in the European Terrestrial Reference System. Processing of the captured images consisted in reconstruction of a three-dimensional model using the principles of Structure from Motion (SfM. Particular care was necessary due to the vegetation: filtering of the dense cloud, mainly based on slope detection, was performed to minimize this issue. Final products of the SfM approach were represented by Digital Elevation Models (DEMs of the sandy coastal environment. Each model was validated by comparison through specially surveyed points. Other analyses were also performed, such as cross sections and computing elevation variations over time. The use of digital photogrammetry by UAVs is particularly reliable: fast acquisition of the images, reconstruction of high-density point clouds, high resolution of final elevation models, as well as flexibility, low cost and accuracy comparable with other available techniques.

  12. Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE): Conceptual Design Report. Volume 1: The LBNF and DUNE Projects

    Energy Technology Data Exchange (ETDEWEB)

    Acciarri, R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); et al.

    2016-01-22

    This document presents the Conceptual Design Report (CDR) put forward by an international neutrino community to pursue the Deep Underground Neutrino Experiment at the Long-Baseline Neutrino Facility (LBNF/DUNE), a groundbreaking science experiment for long-baseline neutrino oscillation studies and for neutrino astrophysics and nucleon decay searches. The DUNE far detector will be a very large modular liquid argon time-projection chamber (LArTPC) located deep underground, coupled to the LBNF multi-megawatt wide-band neutrino beam. DUNE will also have a high-resolution and high-precision near detector.

  13. Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 1: The LBNF and DUNE Projects

    CERN Document Server

    Acciarri, R.; Adamowski, M.; Adams, C.; Adamson, P.; Adhikari, S.; Ahmad, Z.; Albright, C.H.; Alion, T.; Amador, E.; Anderson, J.; Anderson, K.; Andreopoulos, C.; Andrews, M.; Andrews, R.; Anghel, I.; Anjos, J. d.; Ankowski, A.; Antonello, M.; Aranda Fernandez, A.; Ariga, A.; Ariga, T.; Aristizabal, D.; Arrieta-Diaz, E.; Aryal, K.; Asaadi, J.; Asner, D.; Athar, M.S.; Auger, M.; Aurisano, A.; Aushev, V.; Autiero, D.; Avila, M.; Back, J.J.; Bai, X.; Baibussinov, B.; Baird, M.; Balantekin, B.; Baller, B.; Ballett, P.; Bambah, B.; Bansal, M.; Bansal, S.; Barker, G.J.; Barletta, W.A.; Barr, G.; Barros, N.; Bartosz, B.; Bartoszek, L.; Bashyal, A.; Bass, M.; Bay, F.; Beacom, J.; Behera, B.R.; Bellettini, G.; Bellini, V.; Beltramello, O.; Benekos, N.; Benetti, P.A.; Bercellie, A.; Bergevin, M.; Berman, E.; Berns, H.; Bernstein, R.; Bertolucci, S.; Bhandari, B.; Bhatnagar, V.; Bhuyan, B.; Bian, J.; Biery, K.; Bishai, M.; Blackburn, T.; Blake, A.; Blaszczyk, F. d. M.; Blaufuss, E.; Bleakley, B.; Blucher, E.; Bocean, V.; Boffelli, F.; Boissevain, J.; Bolognesi, S.; Bolton, T.; Bonesini, M.; Boone, T.; Booth, C.; Bordoni, S.; Borysova, M.; Bourguille, B.; Boyd, S.B.; Brailsford, D.; Brandt, A.; Bremer, J.; Brice, S.; Bromberg, C.; Brooijmans, G.; Brown, G.; Brown, R.; Brunetti, G.; Bu, X.; Buchanan, N.; Budd, H.; Bugg, B.; Calafiura, P.; Calligarich, E.; Calvo, E.; Camilleri, L.; Campanelli, M.; Cantini, C.; Carls, B.; Carr, R.; Cascella, M.; Castromonte, C.; Mur, E.Catano; Cavanna, F.; Centro, S.; Cervera Villanueva, A.; Chalifour, M.; Chandratre, V.B.; Chatterjee, A.; Chattopadhyay, S.; Chattopadhyay, S.; Chaussard, L.; Chembra, S.; Chen, H.; Chen, K.; Chen, M.; Cherdack, D.; Chi, C.; Childress, S.; Choubey, S.; Choudhary, B.C.; Christodoulou, G.; Christofferson, C.; Church, E.; Cianci, D.; Cline, D.; Coan, T.; Cocco, A.; Coelho, J.; Cole, P.; Collin, G.; Conrad, J.M.; Convery, M.; Corey, R.; Corwin, L.; Cranshaw, J.; Crivelli, P.; Cronin-Hennessy, D.; Curioni, A.; Cushing, J.; Adams, D.L.; Dale, D.; Das, S.R.; Davenne, T.; Davies, G.S.; Davies, J.; Dawson, J.; De, K.; de Gouvea, A.; de Jong, J.K.; de Jong, P.; De Lurgio, P.; Decowski, M.; Delbart, A.; Densham, C.; Dharmapalan, R.; Dhingra, N.; Di Luise, S.; Diamantopoulou, M.; Diaz, J.S.; Diaz Bautista, G.; Diwan, M.; Djurcic, Z.; Dolph, J.; Drake, G.; Duchesneau, D.; Duvernois, M.; Duyang, H.; Dwyer, D.A.; Dye, S.; Dytman, S.; Eberly, B.; Edgecock, R.; Edmunds, D.; Elliott, S.; Elnimr, M.; Emery, S.; Endress, E.; Eno, S.; Ereditato, A.; Escobar, C.O.; Evans, J.; Falcone, A.; Falk, L.; Farbin, A.; Farnese, C.; Farzan, Y.; Fava, A.; Favilli, L.; Felde, J.; Felix, J.; Fernandes, S.; Fields, L.; Finch, A.; Fitton, M.; Fleming, B.; Forest, T.; Fowler, J.; Fox, W.; Fried, J.; Friedland, A.; Fuess, S.; Fujikawa, B.; Gago, A.; Gallagher, H.; Galymov, S.; Gamble, T.; Gandhi, R.; Garcia-Gamez, D.; Gardiner, S.; Garvey, G.; Gehman, V.M.; Gendotti, A.; Geronimo, G. d.; Ghag, C.; Ghoshal, P.; Gibin, D.; Gil-Botella, I.; Gill, R.; Girardelli, D.; Giri, A.; Glavin, S.; Goeldi, D.; Golapinni, S.; Gold, M.; Gomes, R.A.; Gomez Cadenas, J.J.; Goodman, M.C.; Gorbunov, D.; Goswami, S.; Graf, N.; Graf, N.; Graham, M.; Gramelini, E.; Gran, R.; Grant, C.; Grant, N.; Greco, V.; Greenlee, H.; Greenler, L.; Greenley, C.; Groh, M.; Grullon, S.; Grundy, T.; Grzelak, K.; Guardincerri, E.; Guarino, V.; Guarnaccia, E.; Guedes, G.P.; Guenette, R.; Guglielmi, A.; Habig, A.T.; Hackenburg, R.W.; Hackenburg, A.; Hadavand, H.; Haenni, R.; Hahn, A.; Haigh, M.D.; Haines, T.; Hamernik, T.; Handler, T.; Hans, S.; Harris, D.; Hartnell, J.; Hasegawa, T.; Hatcher, R.; Hatzikoutelis, A.; Hays, S.; Hazen, E.; Headley, M.; Heavey, A.; Heeger, K.; Heise, J.; Hennessy, K.; Hewes, J.; Higuera, A.; Hill, T.; Himmel, A.; Hogan, M.; Holanda, P.; Holin, A.; Honey, W.; Horikawa, S.; Horton-Smith, G.; Howard, B.; Howell, J.; Hurh, P.; Huston, J.; Hylen, J.; Imlay, R.; Insler, J.; Introzzi, G.; Ioanisyan, D.; Ioannisian, A.; Iwamoto, K.; Izmaylov, A.; Jackson, C.; Jaffe, D.E.; James, C.; James, E.; Jediny, F.; Jen, C.; Jhingan, A.; Jimenez, S.; Jo, J.H.; Johnson, M.; Johnson, R.; Johnstone, J.; Jones, B.J.; Joshi, J.; Jostlein, H.; Jung, C.K.; Junk, T.; Kaboth, A.; Kadel, R.; Kafka, T.; Kalousis, L.; Kamyshkov, Y.; Karagiorgi, G.; Karasavvas, D.; Karyotakis, Y.; Kaur, A.; Kaur, P.; Kayser, B.; Kazaryan, N.; Kearns, E.; Keener, P.; Kemboi, S.; Kemp, E.; Kettell, S.H.; Khabibullin, M.; Khandaker, M.; Khotjantsev, A.; Kirby, B.; Kirby, M.; Klein, J.; Kobilarcik, T.; Kohn, S.; Koizumi, G.; Kopylov, A.; Kordosky, M.; Kormos, L.; Kose, U.; Kostelecky, A.; Kramer, M.; Kreslo, I.; Kriske, R.; Kropp, W.; Kudenko, Y.; Kudryavtsev, V.A.; Kulagin, S.; Kumar, A.; Kumar, G.; Kumar, J.; Kumar, L.; Kutter, T.; Laminack, A.; Lande, K.; Lane, C.; Lang, K.; Lanni, F.; Learned, J.; Lebrun, P.; Lee, D.; Lee, H.; Lee, K.; Lee, W.M.; Leigui de Oliveira, M.A.; Li, Q.; Li, S.; Li, S.; Li, X.; Li, Y.; Li, Z.; Libo, J.; Lin, C.S.; Lin, S.; Ling, J.; Link, J.; Liptak, Z.; Lissauer, D.; Littenberg, L.; Littlejohn, B.; Liu, Q.; Liu, T.; Lockwitz, S.; Lockyer, N.; Loew, T.; Lokajicek, M.; Long, K.; Lopes, M.D.L.; Lopez, J.P.; Losecco, J.; Louis, W.; Lowery, J.; Luethi, M.; Luk, K.; Lundberg, B.; Lundin, T.; Luo, X.; Lux, T.; Lykken, J.; Machado, A.A.; Macier, J.R.; Magill, S.; Mahler, G.; Mahn, K.; Malek, M.; Malhotra, S.; Malon, D.; Mammoliti, F.; Mancina, S.; Mandal, S.K.; Mandodi, S.; Manly, S.L.; Mann, A.; Marchionni, A.; Marciano, W.; Mariani, C.; Maricic, J.; Marino, A.; Marshak, M.; Marshall, C.; Marshall, J.; Marteau, J.; Martin-Albo, J.; Martinez, D.; Matsuno, S.; Matthews, J.; Mauger, C.; Mavrokoridis, K.; Mayilyan, D.; Mazzucato, E.; McCauley, N.; McCluskey, E.; McConkey, N.; McDonald, K.; McFarland, K.S.; McGowan, A.M.; McGrew, C.; McKeown, R.; McNulty, D.; McTaggart, R.; Mefodiev, A.; Mehrian, M.; Mehta, P.; Mei, D.; Mena, O.; Menary, S.; Mendez, H.; Menegolli, A.; Meng, G.; Meng, Y.; Mertins, D.; Merritt, H.; Messier, M.; Metcalf, W.; Mewes, M.; Meyer, H.; Miao, T.; Milincic, R.; Miller, W.; Mills, G.; Mineev, O.; Miranda, O.; Mishra, C.S.; Mishra, S.R.; Mitrica, B.; Mladenov, D.; Mocioiu, I.; Mohanta, R.; Mokhov, N.; Montanari, C.; Montanari, D.; Moon, J.; Mooney, M.; Moore, C.; Morfin, J.; Morgan, B.; Morris, C.; Morse, W.; Moss, Z.; Mossey, C.; Moura, C.A.; Mousseau, J.; Mualem, L.; Muether, M.; Mufson, S.; Murphy, S.; Musser, J.; Musser, R.; Nakajima, Y.; Naples, D.; Napolitano, J.; Navarro, J.; Navas, D.; Nelson, J.; Nessi, M.; Newcomer, M.; Ng, Y.; Nichol, R.; Nicholls, T.C.; Nikolics, K.; Niner, E.; Norris, B.; Noto, F.; Novakova, P.; Novella, P.; Nowak, J.; Nunes, M.S.; O'Keeffe, H.; Oldeman, R.; Oliveira, R.; Olson, T.; Onishchuk, Y.; Osta, J.; Ovsjannikova, T.; Page, B.; Pakvasa, S.; Pal, S.; Palamara, O.; Palazzo, A.; Paley, J.; Palomares, C.; Pantic, E.; Paolone, V.; Papadimitriou, V.; Park, J.; Parke, S.; Parsa, Z.; Pascoli, S.; Patterson, R.; Patton, S.; Patzak, T.; Paulos, B.; Paulucci, L.; Pavlovic, Z.; Pawloski, G.; Peeters, S.; Pennacchio, E.; Perch, A.; Perdue, G.N.; Periale, L.; Perkin, J.D.; Pessard, H.; Petrillo, G.; Petti, R.; Petukhov, A.; Pietropaolo, F.; Plunkett, R.; Pordes, S.; Potekhin, M.; Potenza, R.; Potukuchi, B.; Poudyal, N.; Prokofiev, O.; Pruthi, N.; Przewlocki, P.; Pushka, D.; Qian, X.; Raaf, J.L.; Raboanary, R.; Radeka, V.; Radovic, A.; Raffelt, G.; Rakhno, I.; Rakotondramanana, H.T.; Rakotondravohitra, L.; Ramachers, Y.A.; Rameika, R.; Ramsey, J.; Rappoldi, A.; Raselli, G.; Ratoff, P.; Rebel, B.; Regenfus, C.; Reichenbacher, J.; Reitzner, D.; Remoto, A.; Renshaw, A.; Rescia, S.; Richardson, M.; Rielage, K.; Riesselmann, K.; Robinson, M.; Rochester, L.; Rodrigues, O.B.; Rodrigues, P.; Roe, B.; Rosen, M.; Roser, R.M.; Ross-Lonergan, M.; Rossella, M.; Rubbia, A.; Rubbia, C.; Rucinski, R.; von Rohr, C.Rudolph; Russell, B.; Ruterbories, D.; Saakyan, R.; Sahu, N.; Sala, P.; Samios, N.; Sanchez, F.; Sanchez, M.; Sands, B.; Santana, S.; Santorelli, R.; Santucci, G.; Saoulidou, N.; Scaramelli, A.; Schellman, H.; Schlabach, P.; Schmitt, R.; Schmitz, D.; Schneps, J.; Scholberg, K.; Schukraft, A.; Schwehr, J.; Segreto, E.; Seibert, S.; Sepulveda-Quiroz, J.A.; Sergiampietri, F.; Sexton-Kennedy, L.; Sgalaberna, D.; Shaevitz, M.; Shahi, J.; Shahsavarani, S.; Shanahan, P.; Shankar, S.U.; Sharma, R.; Sharma, R.K.; Shaw, T.; Shrock, R.; Shyrma, I.; Simos, N.; Sinev, G.; Singh, I.; Singh, J.; Singh, J.; Singh, V.; Sinnis, G.; Sippach, W.; Smargianaki, D.; Smy, M.; Snider, E.; Snopok, P.; Sobczyk, J.; Sobel, H.; Soderberg, M.; Solomey, N.; Sondheim, W.; Sorel, M.; Sousa, A.; Soustruznik, K.; Spitz, J.; Spooner, N.J.; Stancari, M.; Stancu, I.; Stefan, D.; Steiner, H.M.; Stewart, J.; Stock, J.; Stoica, S.; Stone, J.; Strait, J.; Strait, M.; Strauss, T.; Striganov, S.; Sulej, R.; Sullivan, G.; Sun, Y.; Suter, L.; Sutera, C.M.; Svoboda, R.; Szczerbinska, B.; Szelc, A.; Soldner-Rembold, S.; Talaga, R.; Tamsett, M.; Tariq, S.; Tatar, E.; Tayloe, R.; Taylor, C.; Taylor, D.; Terao, K.; Thiesse, M.; Thomas, J.; Thompson, L.F.; Thomson, M.; Thorn, C.; Thorpe, M.; Tian, X.; Tiedt, D.; Timm, S.C.; Tonazzo, A.; Tope, T.; Topkar, A.; Torres, F.R.; Torti, M.; Tortola, M.; Tortorici, F.; Toups, M.; Touramanis, C.; Tripathi, M.; Tropin, I.; Tsai, Y.; Tsang, K.V.; Tsenov, R.; Tufanli, S.; Tull, C.; Turner, J.; Tzanov, M.; Tziaferi, E.; Uchida, Y.; Urheim, J.; Usher, T.; Vagins, M.; Vahle, P.; Valdiviesso, G.A.; Valerio, L.; Vallari, Z.; Valle, J.; Van Berg, R.; Van de Water, R.; Van Gemmeren, P.; Varanini, F.; Varner, G.; Vasseur, G.; Vaziri, K.; Velev, G.; Ventura, S.; Verdugo, A.; Viant, T.; Vieira, T.V.; Vignoli, C.; Vilela, C.; Viren, B.; Vrba, T.; Wachala, T.; Wahl, D.; Wallbank, M.; Walsh, N.; Wang, B.; Wang, H.; Wang, L.; Wang, T.; Warburton, T.K.; Warner, D.; Wascko, M.; Waters, D.; Watson, T.B.; Weber, A.; Weber, M.; Wei, W.; Weinstein, A.; Wells, D.; Wenman, D.; Wetstein, M.; White, A.; Whitehead, L.; Whittington, D.; Wilking, M.; Willhite, J.; Wilson, P.; Wilson, R.J.; Winslow, L.; Wittich, P.; Wojcicki, S.; Wong, H.H.; Wood, K.; Worcester, E.; Worcester, M.; Wu, S.; Xin, T.; Yanagisawa, C.; Yang, S.; Yang, T.; Yarritu, K.; Ye, J.; Yeh, M.; Yershov, N.; Yonehara, K.; Yu, B.; Yu, J.; Zalesak, J.; Zalewska, A.; Zamorano, B.; Zang, L.; Zani, A.; Zani, A.; Zavala, G.; Zeller, G.; Zhang, C.; Zhang, C.; Zimmerman, E.D.; Zito, M.; Zwaska, R.

    2016-01-01

    This document presents the Conceptual Design Report (CDR) put forward by an international neutrino community to pursue the Deep Underground Neutrino Experiment at the Long-Baseline Neutrino Facility (LBNF/DUNE), a groundbreaking science experiment for long-baseline neutrino oscillation studies and for neutrino astrophysics and nucleon decay searches. The DUNE far detector will be a very large modular liquid argon time-projection chamber (LArTPC) located deep underground, coupled to the LBNF multi-megawatt wide-band neutrino beam. DUNE will also have a high-resolution and high-precision near detector.

  14. Increasing Risk Awareness: The Coastal Community Resilience Index

    Science.gov (United States)

    Thompson, Jody A.; Sempier, Tracie; Swann, LaDon

    2012-01-01

    As the number of people moving to the Gulf Coast increases, so does the risk of exposure to floods, hurricanes, and other storm-related events. In an effort to assist communities in preparing for future storm events, the Coastal Community Resilience Index was created. The end result is for communities to take actions to address the weaknesses they…

  15. Diversity and associations between coastal habitats and anurans in southernmost Brazil.

    Science.gov (United States)

    Oliveira, Mauro C L M; Dos Santos, Maurício B; Loebmann, Daniel; Hartman, Alexandre; Tozetti, Alexandro M

    2013-01-01

    This study aimed to verify the relationship between habitat and the composition of anuran species in dune and restinga habitats in southernmost Brazil. The habitats were sampled between April 2009 and March 2010 using pitfalls with drift fence. We have captured 13,508 individuals of 12 anuran species. Species richness was lower in the dunes and dominance was higher in the resting. Apparently the less complex plant cover, water availability, and wide daily thermal variation in dunes act as an environmental filter for frogs. This hypothesis is reinforced by the fact that the most abundant species (Physalaemus biligonigerus and Odonthoprynus maisuma) bury themselves in the sand, minimizing these environmental stresses. Despite being in the Pampa biome, the studied community was more similar to those of coastal restinga environment of southeast Brazil than with other of the Pampa biome. The number of recorded species is similar to those observed in other open habitats in Brazil, showing the importance of adjacent ones to the shoreline for the maintenance of the diversity of anurans in southernmost Brazil.

  16. Hurricane Gustav: Observations and Analysis of Coastal Change

    Science.gov (United States)

    Doran, Kara S.; Stockdon, Hilary F.; Plant, Nathaniel G.; Sallenger, Asbury H.; Guy, Kristy K.; Serafin, Katherine A.

    2009-01-01

    Understanding storm-induced coastal change and forecasting these changes require knowledge of the physical processes associated with a storm and the geomorphology of the impacted coastline. The primary physical processes of interest are the wind field, storm surge, currents, and wave field. Not only does wind cause direct damage to structures along the coast, but it is ultimately responsible for much of the energy that is transferred to the ocean and expressed as storm surge, mean currents, and surface waves. Waves and currents are the processes most responsible for moving sediments in the coastal zone during extreme storm events. Storm surge, which is the rise in water level due to the wind, barometric pressure, and other factors, allows both waves and currents to attack parts of the coast not normally exposed to these processes. Coastal geomorphology, including shapes of the shoreline, beaches, and dunes, is also a significant aspect of the coastal change observed during extreme storms. Relevant geomorphic variables include sand dune elevation, beach width, shoreline position, sediment grain size, and foreshore beach slope. These variables, in addition to hydrodynamic processes, can be used to predict coastal vulnerability to storms. The U.S. Geological Survey (USGS) National Assessment of Coastal Change Hazards project (http://coastal.er.usgs.gov/hurricanes) strives to provide hazard information to those concerned about the Nation's coastlines, including residents of coastal areas, government agencies responsible for coastal management, and coastal researchers. As part of the National Assessment, observations were collected to measure morphological changes associated with Hurricane Gustav, which made landfall near Cocodrie, Louisiana, on September 1, 2008. Methods of observation included oblique aerial photography, airborne topographic surveys, and ground-based topographic surveys. This report documents these data-collection efforts and presents qualitative and

  17. Human impacts quantification on the coastal landforms of Gran Canaria Island (Canary Islands)

    Science.gov (United States)

    Ferrer-Valero, Nicolás; Hernández-Calvento, Luis; Hernández-Cordero, Antonio I.

    2017-06-01

    The coastal areas of the Canary Islands are particularly sensitive to changes, both from a natural perspective and for their potential socio-economic implications. In this paper, the state of conservation of an insular coast is approached from a geomorphological point of view, considering recent changes induced by urban and tourism development. The analysis is applied to the coast of Gran Canaria, a small Atlantic island of volcanic origin, subject to a high degree of human pressure on its coastal areas, especially in recent decades. Currently, much of the economic activity of Gran Canaria is linked to mass tourism, associated with climatic and geomorphological features of the coast. This work is addressed through detailed mapping of coastal landforms across the island (256 km perimeter), corresponding to the period before the urban and tourism development (late 19th century for the island's capital, mid-20th century for the rest of the island) and today. The comparison between the coastal geomorphology before and after the urban and tourism development was established through four categories of human impacts, related to their conservation state: unaltered, altered, semi-destroyed and extinct. The results indicate that 43% of coastal landforms have been affected by human impacts, while 57% remain unaltered. The most affected are sedimentary landforms, namely coastal dunes, palaeo-dunes, beaches and wetlands. Geodiversity loss was also evaluated by applying two diversity indices. The coastal geodiversity loss by total or partial destruction of landforms is estimated at - 15.2%, according to Shannon index (H‧), while it increases to - 32.1% according to an index proposed in this paper. We conclude that the transformations of the coast of Gran Canaria induced by urban and tourism development have heavily affected the most singular coastal landforms (dunes, palaeo-dunes and wetlands), reducing significantly its geodiversity.

  18. Spatio-temporal variability in accretion and erosion of coastal foredunes in the Netherlands: regional climate and local topography

    NARCIS (Netherlands)

    Keijsers, J.G.S.; Poortinga, A.; Riksen, M.J.P.M.; Maroulis, J.

    2014-01-01

    Depending on the amount of aeolian sediment input and dune erosion, dune size and morphology change over time. Since coastal foredunes play an important role in the Dutch coastal defence, it is important to have good insight in the main factors that control these changes. In this paper the temporal

  19. Advanced InSAR imaging for dune mapping

    Science.gov (United States)

    Havivi, Shiran; August, Yitzhak; Blumberg, Dan G.; Rotman, Stanley R.

    2015-04-01

    Aeolian morphologies are formed in the presence of sufficient wind energy and available particles. These processes occur naturally or are further enhanced or reduced by human intervention. The dimensions of change are dependent primarily on the wind energy and surface properties. Since the 1970's, remote sensing imagery both optical and radar, are used for documentation and interpretation of the geomorphologic changes of sand dunes. Remote sensing studies of Aeolian morphologies is mostly useful to document major changes, yet, subtle changes, occurring in a period of days or months in scales of centimeters, are very difficult to detect in imagery. Interferometric Synthetic Aperture Radar (InSAR) is an imaging technique for measuring Earth's surface topography and deformation. InSAR images are produced by measuring the radar phase difference between two separated antennas that view the same surface area. Classical InSAR is based on high coherence between two images or more. The output (interferogram) can show subtle changes with an accuracy of several millimeters to centimeters. Very little work has been done on measuring or identifying the changes in dunes using InSAR. The reason is that dunes tend to be less coherent than firm, stable, surfaces. This research aims to demonstrate how interferometric decorrelation, or, coherence change detection, can be used for identifying dune instability. We hypothesize and demonstrate that the loss of radar coherence over time on dunes can be used as an indication of the dune's instability. When SAR images are acquired at sufficiently close intervals one can measure the time it takes to lose coherence and associate this time with geomorphic stability. To achieve our goals, the Nitzanim coastal dunes along the Mediterranean, 40 km south of Tel-Aviv, Israel, were chosen as a case study. The dunes in this area are of varying levels of stability and vegetation cover and have been monitored meteorologically, geomorphologically and

  20. Beach-dune dynamics: Spatio-temporal patterns of aeolian sediment transport under complex offshore airflow

    Science.gov (United States)

    Lynch, K.; Jackson, D.; Delgado-Fernandez, I.; Cooper, J. A.; Baas, A. C.; Beyers, M.

    2010-12-01

    This study examines sand transport and wind speed across a beach at Magilligan Strand, Northern Ireland, under offshore wind conditions. Traditionally the offshore component of local wind regimes has been ignored when quantifying beach-dune sediment budgets, with the sheltering effect of the foredune assumed to prohibit grain entrainment on the adjoining beach. Recent investigations of secondary airflow patterns over coastal dunes have suggested this may not be the case, that the turbulent nature of the airflow in these zones enhances sediment transport potential. Beach sediment may be delivered to the dune toe by re-circulating eddies under offshore winds in coastal areas, which may explain much of the dynamics of aeolian dunes on coasts where the dominant wind direction is offshore. The present study investigated aeolian sediment transport patterns under an offshore wind event. Empirical data were collected using load cell traps, for aeolian sediment transport, co-located with 3-D ultrasonic anemometers. The instrument positioning on the sub-aerial beach was informed by prior analysis of the airflow patterns using computational fluid dynamics. The array covered a total beach area of 90 m alongshore by 65 m cross-shore from the dune crest. Results confirm that sediment transport occurred in the ‘sheltered’ area under offshore winds. Over short time and space scales the nature of the transport is highly complex; however, preferential zones for sand entrainment may be identified. Alongshore spatial heterogeneity of sediment transport seems to show a relationship to undulations in the dune crest, while temporal and spatial variations may also be related to the position of the airflow reattachment zone. These results highlight the important feedbacks between flow characteristics and transport in a complex three dimensional surface.

  1. Quantifying thresholds for significant dune erosion along the Sefton Coast, Northwest England

    Science.gov (United States)

    Esteves, Luciana S.; Brown, Jennifer M.; Williams, Jon J.; Lymbery, Graham

    2012-03-01

    Field and model hindcast data are used to establish a critical dune erosion threshold for the Sefton Coast (NW England). Events are classified as causing significant erosion if they result in: (a) a mean dune retreat along the entire study area of > 2 m; (b) a dune retreat of ≥ 5 m along a coastal segment ≥ 2 km in length; and (c) an eroded area ≥ 20,000 m2. For the period 1996 to 2008, individual storms were characterised using hindcast results from a POLCOMS-WAM model and measured data from the Liverpool Bay Coastal Observatory. Results show that combined extreme surge levels (> 1.5 m) and wave heights (> 4 m), or tidal water levels above 9.0 m Chart Datum (CD), do not always result in significant dune erosion. Evidence suggests that erosion is more likely to occur when wave heights are > 2.6 m, peak water level is > 10.2 m CD at Liverpool and when consecutive tidal cycles provide 10 h or more of water levels above 9.4 m CD. However, lower water levels and wave heights, and shorter events of sustained water levels, can cause significant erosion in the summer. While the return period for events giving rise to the most severe erosion in the winter is > 50 years, significant erosion in the summer can be caused by events with return periods dune toe elevation c. 30 cm. Although the study shows it might be possible to characterise objectively storm events based on oceanographic conditions, the resultant morphological change at the coast is demonstrated to depend on the time and duration of events, and on other variables which are not so easy to quantify. Further investigation is needed to understand the influence of alongshore and seasonal variability in beach/dune morphology in determining the response to the hydrodynamic and meteorological conditions causing significant erosion. Improved monitoring pre- and post-storm of changes in beach/dune morphology is required to develop reliable proxies that can be used to establish early warning systems to mitigate the

  2. Mycorrhizal status of Lycium europaeum in the coastal dunes of ...

    African Journals Online (AJOL)

    SARAH

    2013-11-30

    Nov 30, 2013 ... to fix the mobile dunes and to protect the reserve of Sidi Boughaba threatened by the progress of sand. Mycorrhization probably .... 90°C in the water bath until the roots became white. Roots were then rinsed, after this; ..... early in the vegetation succession on degraded soil and promote subsequently the ...

  3. Coupling centennial-scale shoreline change to sea-level rise and coastal morphology in the Gulf of Mexico using a Bayesian network

    Science.gov (United States)

    Plant, Nathaniel G.

    2016-01-01

    Predictions of coastal evolution driven by episodic and persistent processes associated with storms and relative sea-level rise (SLR) are required to test our understanding, evaluate our predictive capability, and to provide guidance for coastal management decisions. Previous work demonstrated that the spatial variability of long-term shoreline change can be predicted using observed SLR rates, tide range, wave height, coastal slope, and a characterization of the geomorphic setting. The shoreline is not suf- ficient to indicate which processes are important in causing shoreline change, such as overwash that depends on coastal dune elevations. Predicting dune height is intrinsically important to assess future storm vulnerability. Here, we enhance shoreline-change predictions by including dune height as a vari- able in a statistical modeling approach. Dune height can also be used as an input variable, but it does not improve the shoreline-change prediction skill. Dune-height input does help to reduce prediction uncer- tainty. That is, by including dune height, the prediction is more precise but not more accurate. Comparing hindcast evaluations, better predictive skill was found when predicting dune height (0.8) compared with shoreline change (0.6). The skill depends on the level of detail of the model and we identify an optimized model that has high skill and minimal overfitting. The predictive model can be implemented with a range of forecast scenarios, and we illustrate the impacts of a higher future sea-level. This scenario shows that the shoreline change becomes increasingly erosional and more uncertain. Predicted dune heights are lower and the dune height uncertainty decreases.

  4. Coastal Community Group for Coastal Resilient in Timbulsloko Village, Sayung, Demak Regency, Indonesia

    Directory of Open Access Journals (Sweden)

    Purnaweni Hartuti

    2018-01-01

    Full Text Available Coastal areas are very dynamic and fragile environment, demanding for policies to preserve these areas as materialized in the Resilient Coastal Development Program (PKPT by the Indonesian government. Amongst the targeted area was Timbulsloko Village in Sayung District, Demak Regency, which coastal areas is severely damaged by erosion. This article analyzed the development of the Coastal Community Group (CCG related to the PKPT program in Timbulsloko village, especially in how the group is empowered to increase the community’s resilient in facing the disaster. This study, applied an analytical descriptive method, used the development of the CCG as phenomenon. Primary data was collected through observation and in-depth interviews with stakeholders, accompanying the secondary data. The result shows that the PKPT funding was mostly spent on infrastructure development and used for project management, not for optimizing local economic empowerment. After the completion of the PKPT, there are no actions or following programs to keep the physical results constructed by the CCG. Accordingly, the orientation towards the CCG building capacity for Timbulsloko community’s ecological resilience had not been optimally implemented. This study recommended a "putting the last first" policy approach to preparing the local community. The government must play a stronger role in encouraging a self-help local group for strong human development

  5. Visualizing Coastal Erosion, Overwash and Coastal Flooding in New England

    Science.gov (United States)

    Young Morse, R.; Shyka, T.

    2017-12-01

    Powerful East Coast storms and their associated storm tides and large, battering waves can lead to severe coastal change through erosion and re-deposition of beach sediment. The United States Geological Survey (USGS) has modeled such potential for geological response using a storm-impact scale that compares predicted elevations of hurricane-induced water levels and associated wave action to known elevations of coastal topography. The resulting storm surge and wave run-up hindcasts calculate dynamic surf zone collisions with dune structures using discrete regime categories of; "collision" (dune erosion), "overwash" and "inundation". The National Weather Service (NWS) recently began prototyping this empirical technique under the auspices of the North Atlantic Regional Team (NART). Real-time erosion and inundation forecasts were expanded to include both tropical and extra-tropical cyclones along vulnerable beaches (hotspots) on the New England coast. Preliminary results showed successful predictions of impact during hurricane Sandy and several intense Nor'easters. The forecasts were verified using observational datasets, including "ground truth" reports from Emergency Managers and storm-based, dune profile measurements organized through a Maine Sea Grant partnership. In an effort to produce real-time visualizations of this forecast output, the Northeastern Regional Association of Coastal Ocean Observing Systems (NERACOOS) and the Gulf of Maine Research Institute (GMRI) partnered with NART to create graphical products of wave run-up levels for each New England "hotspot". The resulting prototype system updates the forecasts twice daily and allows users the ability to adjust atmospheric and sea state input into the calculations to account for model errors and forecast uncertainty. This talk will provide an overview of the empirical wave run-up calculations, the system used to produce forecast output and a demonstration of the new web based tool.

  6. Parabolic dune reactivation and migration at Napeague, NY, USA: Insights from aerial and GPR imagery

    Science.gov (United States)

    Girardi, James D.; Davis, Dan M.

    2010-02-01

    Observations from mapping since the 19th century and aerial imagery since 1930 have been used to study changes in the aeolian geomorphology of coastal parabolic dunes over the last ~ 170 years in the Walking Dune Field, Napeague, NY. The five large parabolic dunes of the Walking Dune Field have all migrated across, or are presently interacting with, a variably forested area that has affected their migration, stabilization and morphology. This study has concentrated on a dune with a particularly complex history of stabilization, reactivation and migration. We have correlated that dune's surface evolution, as revealed by aerial imagery, with its internal structures imaged using 200 MHz and 500 MHz Ground Penetrating Radar (GPR) surveys. Both 2D (transect) and high-resolution 3D GPR imagery image downwind dipping bedding planes which can be grouped by apparent dip angle into several discrete packages of beds that reflect distinct decadal-scale episodes of dune reactivation and growth. From aerial and high resolution GPR imagery, we document a unique mode of reactivation and migration linked to upwind dune formation and parabolic dune interactions with forest trees. This study documents how dune-dune and dune-vegetation interactions have influenced a unique mode of blowout deposition that has alternated on a decadal scale between opposite sides of a parabolic dune during reactivation and migration. The pattern of recent parabolic dune reactivation and migration in the Walking Dune Field appears to be somewhat more complex, and perhaps more sensitive to subtle environmental pressures, than an idealized growth model with uniform deposition and purely on-axis migration. This pattern, believed to be prevalent among other parabolic dunes in the Walking Dune Field, may occur also in many other places where similar observational constraints are unavailable.

  7. Variability and correlations of shoreline and dunes on the southern Baltic coast (CRS Lubiatowo, Poland

    Directory of Open Access Journals (Sweden)

    Zbigniew Pruszak

    2011-03-01

    Full Text Available The paper analyses the results of field investigations into the evolution of the shoreline and dune toe positions in a multi-bar,dissipative coastal zone. The correlations between the changes in the shoreline and the dune toe range from -0.4 to 0.8. It is most often the case that the dune toe is stable while the shoreline moves. Consistent cross-shore migration is slightly more likelyto happen than the divergent or convergent movements of both lines. Shoreline retreat and advance attain respective rates of 0.7 m day-1 and 0.4 m day-1. Deep-water wave energy of about 50 kJ m-1 constitutes the boundary between shore accumulation and erosion.

  8. Geomorphometry in coastal morphodynamics

    Science.gov (United States)

    Guisado-Pintado, Emilia; Jackson, Derek

    2017-04-01

    Geomorphometry is a cross-cutting discipline that has interwoven itself into multiple research themes due to its ability to encompass topographic quantification on many fronts. Its operational focus is largely defined as the extraction of land-surface parameters and earth surface characterisation. In particular, the coastal sciences have been enriched by the use of digital terrain production techniques both on land and in the nearshore/marine area. Numerous examples exist in which the utilisation of field instrumentation (e.g. LIDAR, GPS, Terrestrial Laser Scanning, multi-beam echo-sounders) are used for surface sampling and development of Digital Terrain Models, monitoring topographic change and creation of nearshore bathymetry, and have become central elements in modern investigations of coastal morphodynamics. The coastal zone is a highly dynamic system that embraces variable and at times, inter-related environments (sand dunes, sandy beaches, shoreline and nearshore) all of which require accurate and integrated monitoring. Although coastal studies can be widely diverse (with interconnected links to other related disciplines such as geology or biology), the characterisation of the landforms (coastal geomorphology) and associated processes (morphodynamics, hydrodynamics, aeolian processes) is perhaps where geomorphometry (topo-bathymetry quantification) is best highlighted. In this respect, many tools have been developed (or improved upon) for the acquisition of topographic data that now commands a high degree of accuracy, simplicity, and ultimately acquisition cost reduction. We present a series of field data acquisitions examples that have produced land surface characterisation using a range of techniques including traditional GPS surveys to more recent Terrestrial Laser Scanning and airborne LIDAR. These have been conducted within beach and dune environments and have helped describe erosion and depositional processes driven by wind and wave energy (high

  9. The Carolina Sandhills: Quaternary eolian sand sheets and dunes along the updip margin of the Atlantic Coastal Plain province, southeastern United States

    Science.gov (United States)

    Swezey, Christopher; Fitzwater, Bradley A.; Whittecar, G. Richard; Mahan, Shannon; Garrity, Christopher P.; Aleman Gonzalez, Wilma B.; Dobbs, Kerby M.

    2016-01-01

    The Carolina Sandhills is a physiographic region of the Atlantic Coastal Plain province in the southeastern United States. In Chesterfield County (South Carolina), the surficial sand of this region is the Pinehurst Formation, which is interpreted as eolian sand derived from the underlying Cretaceous Middendorf Formation. This sand has yielded three clusters of optically stimulated luminescence ages: (1) 75 to 37 thousand years ago (ka), coincident with growth of the Laurentide Ice Sheet; (2) 28 to 18 ka, coincident with the last glacial maximum (LGM); and (3) 12 to 6 ka, mostly coincident with the Younger Dryas through final collapse of the Laurentide Ice Sheet. Relict dune morphologies are consistent with winds from the west or northwest, coincident with modern and inferred LGM January wind directions. Sand sheets are more common than dunes because of effects of coarse grain size (mean range: 0.35–0.59 mm) and vegetation. The coarse grain size would have required LGM wind velocities of at least 4–6 m/sec, accounting for effects of colder air temperatures on eolian sand transport. The eolian interpretation of the Carolina Sandhills is consistent with other evidence for eolian activity in the southeastern United States during the last glaciation.

  10. Intertidal Sandbar Welding as a Primary Source of Sediment for Dune Growth: Evidence from a Large Scale Field Experiment

    Science.gov (United States)

    Cohn, N.; Ruggiero, P.; de Vries, S.

    2016-12-01

    Dunes provide the first line of defense from elevated water levels in low-lying coastal systems, limiting potentially major flooding, economic damages, and loss of livelihood. Despite the well documented importance of healthy dunes, our predictive ability of dune growth, particularly following erosive storm events, remains poor - resulting in part from traditionally studying the wet and dry beach as separate entities. In fact, however, dune recovery and growth is closely tied to the subtidal morphology and the nearshore hydrodynamic conditions, necessitating treating the entire coastal zone from the shoreface to the backshore as an integrated system. In this context, to further improve our understanding of the physical processes allowing for beach and dune growth during fair weather conditions, a large field experiment, the Sandbar-aEolian Dune EXchange EXperiment, was performed in summer 2016 in southwestern Washington, USA. Measurements of nearshore and atmospheric hydrodynamics, in-situ sediment transport, and morphology change provide insight into the time and space scales of nearshore-beach-dune exchanges along a rapidly prograding stretch of coast over a 6 week period. As part of this experiment, the hypothesis that dune growth is limited by the welding of intertidal sandbars to the shoreline (Houser, 2009) was tested. Using laser particle counters, bed elevation sensors (sonar altimeters and Microsoft Kinect), continuously logging sediment traps, RGB and IR cameras, and repeat morphology surveys (terrestrial lidar, kite based structure from motion, and RTK GPS), spatial and temporal trends in aeolian sediment transport were assessed in relation to the synoptic onshore migration and welding of intertidal sandbars. Observations from this experiment demonstrate that (1) the intertidal zone is the primary source of sediment to the dunes during non-storm conditions, (2) rates of saltation increase during later stages of bar welding but equivalent wind conditions

  11. Effect of the recent land use on the plant diversity and community structure of Omayed Biosphere Reserve, Egypt

    Directory of Open Access Journals (Sweden)

    Dalia A. Ahmed

    2015-07-01

    Full Text Available The present study aims at describing and analysing the floristic composition and vegetation types, as well as determining the effect of recent land uses on the vegetation structure. It aims also at identifying the alien plants species and elucidating the impact of these species on the plant diversity and community structure of the study area. One hundred and ninety stands were selected monthly for this study, 145 species were recorded (69 perennials and 76 annuals related to 83 genera, 40 families in 9 identified habitats in El-Omayed Biosphere Reserve (coastal sand dunes, salt marshes, saline depression, non-saline depression, inland ridges, inland plateau, irrigation canals, road sides and cultivated lands. Therophytes were the most represented life form. Three habitat groups resulted after the application of TWINSPAN and DCA as classification and ordination techniques: 2 represented the natural habitats and one represented the urban and cultivated habitats. Group I represented coastal dunes and salt marshes GII: saline depressions, non-saline depressions, inland plateau and inland ridges and GIII: irrigation canals, road sides and cultivated lands. Coastal dunes had the highest species richness (α-diversity, followed by cultivated lands, while inland plateau had the lowest; but saline depressions had the highest species turnover (β-diversity. Non-saline depressions had the highest relative evenness, while saline depressions had the highest relative concentration of dominance. Coastal dunes had highest values of calcium carbonates and calcium ions, and salt marshes had the highest salinity, pH, potassium and sodium contents, but cultivated lands had the highest values of silt, clay and organic matter. The diagram resulting from CCA showed an influence of most soil variables, except nitrogen, calcium and potassium. Twenty two species were recorded for the first time in the study area. The recent land use (overgrazing, wood cutting and

  12. Thermal biology of Liolaemus occipitalis (Squamata, Tropiduridae in the coastal sand dunes of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    C. S. Bujes

    Full Text Available The thermal biology of the small sand lizard, Liolaemus occipitalis, was studied in the coastal sand dunes at Quintão Beach (Palmares do Sul, Rio Grande do Sul, Brazil; 30° 24' S and 50° 17' W, between September, 1998 and August, 1999. Liolaemus occipitalis presented a mean body temperature of 30.89 °C (SD = 4.43 °C; min = 16.4 °C; max = 40.2 °C; N = 270, that varied on a daily and seasonal basis according to microhabitat thermal alterations. The substrate temperature was the main heat source for thermoregulation of L. occipitalis as in all seasons of the year it was responsible for the animals' temperature variation (82% of the collected lizards in the spring; 60% in the summer; 84% in the fall and 68% in the winter. The results indicate that L. occipitalis is a saxicolous, thigmothermic and heliothermic species that regulates its body temperature through behavioral mechanisms.

  13. Structure and floristic pattern of a coastal dunes in southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Augusto Giaretta

    2013-03-01

    Full Text Available The Brazilian shrublands area (restinga is composed of marine coast vegetation on Quaternary sandy plains, where the species composition can vary depending on the surrounding ecosystems. The aims of this study were to describe the structure and floristic composition of a restinga near the community of Itaúnas, in the northern part of the state of Espírito Santo, to identify any relationships between this restinga and surrounding plant formations, and to determine which are the species that occur preferentially in the coastal forests of Espírito Santo. We sampled woody plants with a diameter at breast height > 2.5 cm, excluding lianas, in 50 plots of 100 m². We selected studies of coastal forests in the states of Espírito Santo and Bahia to prepare a database that would reveal patterns of floristic variation among these areas. We used t wo-way indicator species analysis for the identification of the species that occur preferentially in the coastal forests of Espírito Santo. We identified 114 species belonging to 38 families. Species richness was greatest for Myrtaceae (26 species, followed by Fabaceae (10. The Shannon index for the study area was 3.96. The estimated total density was 3,330 individuals/ha and basal area was 32.02 m²/ha. The highest importance value (IV was for Protium heptaphyllum (IV, 23.4, indicating that it is characteristic of the Espírito Santo restinga. The results of our floristic analysis indicate that the species composition of the Itaúnas restinga is influenced by the so-called tabuleiro forests (coastal lowland forests on Tertiary deposits, which are most common in northern Espírito Santo. This seems to be the main factor responsible for the gradual reduction in floristic similarity between the restingas in the north of Espírito Santo and those in the south of the state, each constituting a distinct floristic block. In addition, we generated lists of species that occur preferentially in the restinga and

  14. From grey to green: Efficacy of eco-engineering solutions for nature-based coastal defence.

    Science.gov (United States)

    Morris, Rebecca L; Konlechner, Teresa M; Ghisalberti, Marco; Swearer, Stephen E

    2018-05-01

    Climate change is increasing the threat of erosion and flooding along coastlines globally. Engineering solutions (e.g. seawalls and breakwaters) in response to protecting coastal communities and associated infrastructure are increasingly becoming economically and ecologically unsustainable. This has led to recommendations to create or restore natural habitats, such as sand dunes, saltmarsh, mangroves, seagrass and kelp beds, and coral and shellfish reefs, to provide coastal protection in place of (or to complement) artificial structures. Coastal managers are frequently faced with the problem of an eroding coastline, which requires a decision on what mitigation options are most appropriate to implement. A barrier to uptake of nature-based coastal defence is stringent evaluation of the effectiveness in comparison to artificial protection structures. Here, we assess the current evidence for the efficacy of nature-based vs. artificial coastal protection and discuss future research needs. Future projects should evaluate habitats created or restored for coastal defence for cost-effectiveness in comparison to an artificial structure under the same environmental conditions. Cost-benefit analyses should take into consideration all ecosystem services provided by nature-based or artificial structures in addition to coastal protection. Interdisciplinary research among scientists, coastal managers and engineers is required to facilitate the experimental trials needed to test the value of these shoreline protection schemes, in order to support their use as alternatives to artificial structures. This research needs to happen now as our rapidly changing climate requires new and innovative solutions to reduce the vulnerability of coastal communities to an increasingly uncertain future. © 2018 John Wiley & Sons Ltd.

  15. Assessment of beach and dune erosion and accretion using LiDAR: Impact of the stormy 2013-14 winter and longer term trends on the Sefton Coast, UK

    Science.gov (United States)

    Pye, Kenneth; Blott, Simon J.

    2016-08-01

    An important question for coastal management concerns the importance of individual storms and clusters of storms on longer term beach sediment budgets, beach and dune erosion, and coastal flood risk. Between October 2013 and March 2014 a series of deep Atlantic low pressure systems crossed the Northeast Atlantic, and strong winds, high waves and high water levels affected many coastal areas in the UK and other parts of western Europe. Net dune recession of up to 12.1 m occurred around Formby Point. On 5 December 2013 the highest water level ever recorded at Liverpool (6.22 m ODN) coincided with waves of Hs of 4.55 m and Tp of 9.3 s in Liverpool Bay. Wave trimming of the dune toe occurred along the entire length of the Sefton coast, but significant dune erosion occurred only where the upper beach (between the mean high water spring tide level and the dune toe) was dune system, mostly at Formby Point. However, some parts of the beach to the south of Formby Point gained sediment, indicating net north to south transport over the winter. When considered in a longer term context, the 2013-14 winter represents only a small perturbation on the longer-term coast trend of erosion at Formby Point and progradation to the north and south. Analysis of LiDAR data over a longer time period 1999-2014 indicated upper beach and dune sediment loss of 780 × 103 m3 from the north-central part of Formby Point, with net gains of 806 × 103 m3 and 2116 × 103 m3 in areas to the north and south, respectively. This indicates a net onshore transport of 2142 × 103 m3 from Liverpool Bay towards the coast between Birkdale and Altcar, with a further net total of 210 × 103 m3 transported towards the shore between Altcar and Crosby. In view of the demonstrated value of airborne LiDAR surveys for the quantification of storm impacts and longer term coastal changes, it is recommended that such surveys should be undertaken before and after each winter storm period, covering the area between mean low

  16. protoDUNE-Single Phase and protDUNE-DualPhase

    CERN Multimedia

    Brice, Maximilien

    2016-01-01

    At the EHN1 two big 8m x 8m x8m detector prototypes (protoDUNE-Single Phase and protDUNE-DualPhase) are being constructed. The aim is to test technologies and detector performances for DUNE, a new generation of LBN neutr

  17. Impacts of Coastal Inundation Due to Climate Change in a CLUSTER of Urban Coastal Communities in Ghana, West Africa

    Directory of Open Access Journals (Sweden)

    Patrick Kwabena Ofori-Danson

    2011-09-01

    Full Text Available The increasing rates of sea level rise caused by global warming within the 21st century are expected to exacerbate inundation and episodic flooding tide in low-lying coastal environments. This development threatens both human development and natural habitats within such coastal communities. The impact of sea level rise will be more pronounced in developing countries where there is limited adaptation capacity. This paper presents a comprehensive assessment of the expected impacts of sea level rise in three communities in the Dansoman coastal area of Accra, Ghana. Future sea level rises were projected based on global scenarios and the Commonwealth Scientific and Industrial Research Organization General Circulation Models—CSIRO_MK2_GS GCM. These were used in the SimCLIM model based on the modified Bruun rule and the simulated results overlaid on near vertical aerial photographs taken in 2005. It emerged that the Dansoman coastline could recede by about 202 m by the year 2100 with baseline from 1970 to 1990. The potential impacts on the socioeconomic and natural systems of the Dansoman coastal area were characterized at the Panbros, Grefi and Gbegbeyise communities. The study revealed that about 84% of the local dwellers is aware of the rising sea level in the coastal area but have poor measures of adapting to the effects of flood disasters. Analysis of the likely impacts of coastal inundation revealed that about 650,000 people, 926 buildings and a total area of about 0.80 km2 of land are vulnerable to permanent inundation by the year 2100. The study has shown that there will be significant losses to both life and property by the year 2100 in the Dansoman coastal community in the event of sea level rise.

  18. Variability of sediment transport in beach and coastal dune environments, Brittany, France

    Science.gov (United States)

    Regnauld, Hervé; Louboutin, Roland

    2002-06-01

    On the coasts of Brittany (English Channel and Bay of Biscay), barrier systems were surveyed between 1995 and 2000. The beach profiles have a very high variability, which cannot be statistically explained by linear correlation with the wind, the waves, or the tides. The behaviour of the profile is represented on a phase diagram (speed of profile change: Y-axis, thickness of the profile: X-axis). The points in the center of the profile "rotate" around an average equilibrium which is seldom measured in the field. The seaward edge of the beaches oscillates between loss and gain, but with a net positive budget. The landward top of the beach displays a range of oscillations. The dunes always have a positive budget. The whole behaviour of the system is explained if the precise succession of anticyclonic and cyclonic winds is taken into account. Long periods of easterly winds (offshorewards) tend to produce a calm sea and to increase tidal sediment settling on the seafloor. If an onshore westerly storm occurs just after such a period, it hits a sediment-rich environment and produces a net accumulation on both the beach and the dunes. Periods of westerly calm to moderate winds do not help accumulation: a full going storm will hit a depleted environment and produce erosion. The speed of dune accretion and the budget of the beaches seem to partly depend on the ratio of cyclonic to anticyclonic conditions.

  19. Coupling bacterioplankton populations and environment to community function in coastal temperate waters

    DEFF Research Database (Denmark)

    Traving, S. J.; Bentzon-Tilia, Mikkel; Knudsen-Leerbeck, H.

    2016-01-01

    drivers of bacterioplankton community functions, taking into account the variability in community composition and environmental conditions over seasons, in two contrasting coastal systems. A Least Absolute Shrinkage and Selection Operator (LASSO) analysis of the biological and chemical data obtained from...... surface waters over a full year indicated that specific bacterial populations were linked to measured functions. Namely, Synechococcus (Cyanobacteria) was strongly correlated with protease activity. Both function and community composition showed seasonal variation. However, the pattern of substrate...... of common drivers of bacterioplankton community functions in two different systems indicates that the drivers may be of broader relevance in coastal temperate waters....

  20. Promoting innovative stormwater solutions for coastal plain communities

    OpenAIRE

    Drescher, Sadie

    2010-01-01

    In 2008, the Center for Watershed Protection (CWP) surveyed seventy-three coastal plain communities to determine their current practices and need for watershed planning and low impact development (LID). The survey found that communities had varying watershed planning effectiveness and need better stormwater management, land use planning, and watershed management communication. While technical capacity is improving, stormwater programs are under staffed and innovative site designs ...

  1. Coastal ecosystems for protection against storm surge

    Digital Repository Service at National Institute of Oceanography (India)

    Mascarenhas, A.

    and infrastructure in single catastrophe exceeded Rs. 2750 crore. Economic loss is thus prohibitive and hence unsustainable. This paper acknowledges the intrinsic protective value of coastal sand dunes, vegetation and wetlands as a functional natural defence...

  2. The impact of coastal grabbing on community conservation – a global reconnaissance

    OpenAIRE

    Bavinck, Jan Maarten; Berkes, Fikret; Charles, Anthony; Dias, Ana Carolina Esteves; Doubleday, Nancy; Nayak, Prateep; Sowman, Merle

    2017-01-01

    Source at https://doi.org/10.1186/s40152-017-0062-8 . "Coastal grab" refers to the contested appropriation of coastal (shore and inshore) space and resources by outside interests. This paper explores the phenomenon of coastal grabbing and the effects of such appropriation on community-based conservation of local resources and environment. The approach combines social-ecological systems analysis with socio-legal property rights studies. Evidence of coastal grab is provided from four countr...

  3. Grain-size variations on a longitudinal dune and a barchan dune

    Science.gov (United States)

    Watson, Andrew

    1986-01-01

    The grain-size characteristics of the sand upon two dunes—a 40 m high longitudinal dune in the central Namib Desert and a 6.0 m high barchan in the Jafurah sand sea of Saudi Arabia—vary with position on the dunes. On the longitudinal dune, median grain size decreases, sorting improves and the grain-size distributions are less skewed and more normalized toward the crest. Though sand at the windward toe is distinct, elsewhere on the dune the changes in grain-size characteristics are gradual. An abrupt change in grain size and sorting near the crest—as described by Bagnold (1941, pp. 226-229)—is not well represented on this dune. Coarse grains remain as a lag on concave slope units and small particles are winnowed from the sand on the steepest windward slopes near the crest. Avalanching down slipfaces at the crest acts only as a supplementary grading mechanism. On the barchan dune median grain size also decreases near the crest, but sorting becomes poorer, though the grain-size distributions are more symmetric and more normalized. The dune profile is a Gaussian curve with a broad convex zone at the apex upon which topset beds had accreted prior to sampling. Grain size increases and sorting improves down the dune's slipface. However, this grading mechanism does not influence sand on the whole dune because variations in wind regime bring about different modes of dune accretion. On both dunes, height and morphology appear to influence significantly the grain-size characteristics.

  4. Observations of Interannual Dune Morphological Evolution With Comparisons to Shoreline Change Along the Columbia River Littoral Cell

    Science.gov (United States)

    Doermann, L.; Kaminsky, G. M.; Ruggiero, P.

    2006-12-01

    Beach topographic data have been collected along the 160 km-long Columbia River Littoral Cell in southwest Washington and northwest Oregon, USA as part of the Southwest Washington Coastal Erosion Study and a NANOOS pilot project. The monitoring program includes the collection of cross-shore beach profiles at 49 sites for each of the 34 seasons since 1997 (with few exceptions), enabling the investigation of the seasonal to interannual morphological variability of this high-energy coast. We focus here on the dunes backing the beaches, aiming to quantitatively describe the wide variety of characteristics they exhibit, as well as to relate dune evolution to shoreline change. To analyze the large volume of high-quality data, we use automated algorithms and systematic processes to identify the location of the dune toe, crest, and face, and calculate a volume (where enough data are available) and beach width for each survey. We define the position of the dune face as the elevation half-way between the average dune toe and average dune crest elevations at each profile location, and beach width as the horizontal distance between the 2-m contour (~MSL) and the dune toe. Much like shoreline proxies lower on the beach profile, (e.g., the 3-m contour), the location of the dune toe shows large seasonal variability with onshore deposition of sand in summer months and offshore sand transport in the winter. However, the location of the dune face and the elevation of the dune crest are much less variable and are useful in describing the evolution of the dune/beach system in the horizontal and vertical directions, respectively, over interannual time scales. On beaches with the highest shoreline change rates in the study area, the dune face follows the progradational trend of the shoreline with the dune face prograding at approximately 25-50% of the rate of the shoreline. Along many of these beaches that experienced severe erosion during the El Niño of 1997/98, the dune face

  5. Integrating multi-disciplinary field and laboratory methods to investigate the response and recovery of beach-dune systems in Ireland to extreme events

    Science.gov (United States)

    Farrell, E.; Lynch, K.; Wilkes Orozco, S.; Castro Camba, G.; Scullion, A.

    2017-12-01

    This two year field monitoring project examines the response and recovery of 1.2km of a coastal beach-dune system in the west coast of Ireland (The Maharees, Brandon Bay, Co. Kerry) to storms. The results from this project initiated a larger scale study to assess the long term evolution of Brandon Bay (12km) and patterns of meso-scale rotation. On a bay scale historic shoreline analyses were completed using historic Ordnance Survey maps, aerial photography, and DGPS surveys inputted to the Digital Shoreline Analysis System. These were coupled with a GSTA-wavemeter experiment that collected 410 sediment samples along the beach and nearshore to identify preferred sediment transport pathways along the bay. On a local scale (1.2km) geomorphological changes of the beach and nearshore were monitored using repeated monthly DGPS surveys and drone technology. Topographical data were correlated with atmospheric data obtained from a locally installed automatic weather station, oceanographic data from secondary sources, and photogrammetry using a camera installed at the site collecting pictures every 10 minutes during daylight hours. Changes in surface elevation landward of the foredune from aeolian processes were measured using five pin transects across the dune. The contribution of local blowout dynamics were measured using drone imagery and structure-from-motion technology. The results establish that the average shoreline recession along the 1.2 km site is 72 m during the past 115 years. The topographic surveys illustrate that natural beach building processes initiate system recovery post storms including elevated foreshores and backshores and nearshore sand bar migration across the entire 1.2 km stretch of coastline. In parallel with the scientific work, the local community have mobilized and are working closely with the lead scientists to implement short term coastal management strategies such as signage, information booklets, sand trap fencing, walkways, wooden

  6. Policies for Reducing Coastal Risk on the East and Gulf Coasts

    Science.gov (United States)

    Glickson, D.; Johnson, S.

    2014-12-01

    Hurricane- and coastal storm-related economic losses have increased substantially over the past century, largely due to expanding population and development in susceptible coastal areas. Concurrent with this growth, the federal government has assumed an increasing proportion of the financial responsibility associated with U.S. coastal storms, which may discourage state and local governments from taking appropriate actions to reduce risk and enhance resilience. Strategies to manage coastal storm risks fall into two categories: reducing the probability of flooding or wave impact (such as seawalls, storm surge barriers, beach nourishment, dune building, restoration/expansion of oyster reefs, salt marshes, and mangroves) and reducing the number or vulnerability of people or structures (such as relocation, land-use planning, and elevating or floodproofing buildings). Over the past century, most coastal risk management programs have emphasized coastal armoring, while doing little to decrease development in harm's way. This National Research Council report calls for the development of a national vision for managing coastal risks that includes a long-term view, regional solutions, and recognition of all benefits. A national coastal risk assessment is needed to identify high priority areas. Benefit-cost analysis provides a reasonable framework to evaluate national investments in coastal risk reduction, if constrained by other important environmental, social, and life-safety factors. Extensive collaboration and additional policy changes will be necessary to move from a nation that is primarily reactive to coastal disasters to one that invests wisely in coastal risk reduction and builds resilience among coastal communities.

  7. Nitrogen limitation in the coastal heath at Anholt, Denmark

    DEFF Research Database (Denmark)

    Johnsen, Ib; Christensen, Steen; Riis-Nielsen, Torben

    2014-01-01

    ) and phosphorus as KH2PO4 (P-addition) was carried out in the coastal grey dune vegetation of Anholt. The Naddition corresponded to 40 kg N ha−1 year−1 and the Paddition to 7 kg P ha−1 year−1 The experiment included N-, P-, N + P-addition and control. Lichens (genera: mainly Cladonia, Stereocaulon, Cetraria......The purpose of the study was to investigate, whether the coastal grey dune vegetation at Anholt, Denmark, is limited by nitrogen or phosphorus. The island Anholt (22,37 km2) is situated in the centre of Kattegat A two factor fertilization experiment with nitrogen as NH4NO3 (Naddition...... significantly following N and N + P addition. No effect was observed by P addition alone. N limitation of this coastal heath vegetation remote from agricultural and industrial activities was evident. The effect on the plant species of the single application was short-lived. After two-three years of enhanced...

  8. Community Participation for Sustainable Tourism Model in Manado Coastal Area

    Science.gov (United States)

    Warouw, F. F.; Langitan, F. W.; Alamsyah, A. T.

    2018-02-01

    Manado city with the potential for coastal tourism which is at the center of the world’s coral triangle is developing a tourism development policy. Tourism that is being developed should certainly be able to adapt to changing conditions of today’s dynamic environment. The extent to which the adaptation process is determined by the communities involved in the development of tourism. Based on data from the population in the city of Manado, there are currently 410 481 thousand inhabitants. This study tried to reveal the extent of community participation in the city of Manado in particular involvement in the development of tourism in coastal Bay of Manado. Level of community participation in the development of tourism in the city of Manado is measured in the form of quantitative research in the form of questionnaires to the community based on the level of community participation developed by Arnstein Sheery by purposive sampling technique. The level of participation was developed by Arnstein Sheery row of low level ketinggi namely: Manipulation, Therapy, informing, Consultation, placation, partnership, Delegaten Power, Citizen Control. Findings community level participation in the development of coastal tourism on Manado bay civilized level of consultation. Consultation rate shows that the government invite the public opinion after the given information to the public and has been a two-way dialogue between government and society. Community has provided input and active discussion by way of the two-way dialogue. Although there has been a two-way dialogue, but the successful rate is low because there is no guarantee that the concerns and ideas of the community will be considered. This requires the development of community-based programs in order to increase the degree of participation so that community participation will increase. To conclude, the program needs to be based on input from the community’s needs and it has to involve the public directly to tourism

  9. Vulnerability of Coastal Communities from Storm Surge and Flood Disasters

    Science.gov (United States)

    Bathi, Jejal Reddy; Das, Himangshu S.

    2016-01-01

    Disasters in the form of coastal storms and hurricanes can be very destructive. Preparing for anticipated effects of such disasters can help reduce the public health and economic burden. Identifying vulnerable population groups can help prioritize resources for the most needed communities. This paper presents a quantitative framework for vulnerability measurement that incorporates both socioeconomic and flood inundation vulnerability. The approach is demonstrated for three coastal communities in Mississippi with census tracts being the study unit. The vulnerability results are illustrated as thematic maps for easy usage by planners and emergency responders to assist in prioritizing their actions to vulnerable populations during storm surge and flood disasters. PMID:26907313

  10. Macrobenthic community structure of coastal Arabian Sea during the fall intermonsoon

    Digital Repository Service at National Institute of Oceanography (India)

    Ingole, B.S.; Gaonkar, U.V.; Deshmukh, A.; Mukherjee, I.; Sivadas, S.K.; Gophane, A.

    that the FIM period is critical in structuring the coastal benthic community Results indicated Coscinodiscus sp and Thalassiosira sp were dominant in the phytoplankton and the microphytobenthos community Zooplankton was dominated by small sized calanoid...

  11. 3D Airflow patterns over coastal foredunes: implications for aeolian sediment transport

    Science.gov (United States)

    Jackson, Derek W. T.; Cooper, Andrew G.; Baas, Andreas C. W.; Lynch, Kevin; Beyers, Meiring

    2010-05-01

    A fundamental criterion for the development of coastal sand dunes is usually highlighted as a significant onshore wind component of the local wind field. The presence of large sand dune systems on coasts where the predominant wind blows offshore is therefore difficult to explain and usually they are attributed to the past occurrence of onshore winds and, by implication, subsequent changes in climate. Recent studies have shown that offshore winds can be deflected or 'steered' by existing dunes so that their direction changes. This can occur to such an extent that a process known as 'flow reversal' can arise, whereby the initially offshore wind actually flows onshore at the beach. This process is important because it can cause sand to be blown from the beach and into the dunes, causing them to grow. This may be central in explaining the presence of extensive dunes on coasts where the dominant wind is offshore, but is also important in how dunes recover after periods of wave erosion during storms. Offshore winds have traditionally been excluded from sediment budget calculations for coastal dunes, but when they do transport sand onshore, this may have been an important oversight leading to significant underestimates of the volume of sand being transported by wind. This work investigates the controls on the processes and the mechanisms involved in deformation of the flow and resulting sediment transport at coastal foredunes in Northern Ireland. We use a combination of field measurement of wind and sediment transport coupled with state-of-the-art aerodynamic modelling using computational fluid dynamics (CFD) and 3-D sonic anemometry. Our working hypothesis is that offshore winds contribute substantially to foredune behaviour on leeside coasts. Preliminary results show strong reverse flow eddies in the seaward side of the foredunes during offshore wind events. These secondary flow reversals have been above velocity threshold and are transport capable. Using CFD modelling

  12. Optical dating of dune ridges on Rømø

    DEFF Research Database (Denmark)

    Madsen, Anni Tindahl; Murray, A. S.; Andersen, Thorbjørn Joest

    2007-01-01

    The application of optically stimulated luminescence (OSL) to the dating of recent aeolian sand ridges on Rømø, an island off the southwest coast of Denmark, is tested. These sand ridges began to form approximately 300 years ago, and estimates of the ages are available from historical records....... Samples for OSL dating were taken ~0.5 m below the crests of four different dune ridges; at least five samples were recovered from each ridge to test the internal consistency of the ages. Additional samples were recovered from the low lying areas in the swales and from the scattered dune formations......-defined building phases separated by inactive periods and the first major ridge formed ~235 years ago. This study demonstrates that optical dating can be successfully applied to these young aeolian sand deposits, and we conclude that OSL dating is a powerful chronological tool in studies of coastal change....

  13. Knowledge, Attitudes and Practices of Coastal Communities on Waste Management in Ghana

    OpenAIRE

    Essuman, Nasir

    2017-01-01

    Waste management has been a worldwide issue which most countries are finding the best ways of dealing with. Managing waste improperly poses threat to the health of individuals and the environment. Ghana as a developing country, its coastal communities are faced with a lot of challenges regarding waste management due to actions towards waste management. This research seeks to examine the knowledge, attitudes and practices of coastal communities on waste management and how their actions have a...

  14. Community Education in Eastern Chinese Coastal Cities: Issues and Development

    Science.gov (United States)

    Lu, Suju

    2009-01-01

    This paper first reviews the development of community education in Shanghai, one of China's eastern coastal cities. Then the development of community education in the Xuhui District of Shanghai, especially its management system and operational mechanisms, school operating systems and networks, curriculum systems, and team building are presented.…

  15. Nourishment of perched sand dunes and the issue of erosion control in the Great Lakes

    Science.gov (United States)

    Marsh, William M.

    1990-09-01

    Although limited in coverage, perched sand dunes situated on high coastal bluffs are considered the most prized of Great Lakes dunes. Grand Sable Dunes on Lake Superior and Sleeping Bear Dunes on Lake Michigan are featured attractions of national lakeshores under National Park Service management. The source of sand for perched dunes is the high bluff along their lakeward edge. As onshore wind crosses the bluff, flow is accelerated upslope, resulting in greatly elevated levels of wind stress over the slope brow. On barren, sandy bluffs, wind erosion is concentrated in the brow zone, and for the Grand Sable Bluff, it averaged 1 m3/yr per linear meter along the highest sections for the period 1973 1983. This mechanism accounts for about 6,500 m3 of sand nourishment to the dunefield annually and clearly has been the predominant mechanism for the long-term development of the dunefield. However, wind erosion and dune nourishment are possible only where the bluff is denuded of plant cover by mass movements and related processes induced by wave erosion. In the Great Lakes, wave erosion and bluff retreat vary with lake levels; the nourishment of perched dunes is favored by high levels. Lake levels have been relatively high for the past 50 years, and shore erosion has become a major environmental issue leading property owners and politicians to support lake-level regulation. Trimming high water levels could reduce geomorphic activity on high bluffs and affect dune nourishment rates. Locally, nourishment also may be influenced by sediment accumulation associated with harbor protection facilities and by planting programs aimed at stabilizing dunes.

  16. Advanced Interferometric Synthetic Aperture Imaging Radar (InSAR) for Dune Mapping

    Science.gov (United States)

    Havivi, Shiran; Amir, Doron; Schvartzman, Ilan; August, Yitzhak; Mamman, Shimrit; Rotman, Stanely R.; Blumberg, Dan G.

    2016-04-01

    Aeolian morphologies are formed in the presence of sufficient wind energy and available lose particles. These processes occur naturally or are further enhanced or reduced by human intervention. The dimensions of change are dependent primarily on the wind energy and surface properties. Since the 1970s, remote sensing imagery, both optical and radar, have been used for documentation and interpretation of the geomorphologic changes of sand dunes. Remote sensing studies of aeolian morphologies is mostly useful to document major changes, yet, subtle changes, occurring in a period of days or months in scales of centimeters, are very difficult to detect in imagery. Interferometric Synthetic Aperture Radar (InSAR) is an imaging technique for measuring Earth's surface topography and deformation. InSAR images are produced by measuring the radar phase difference between two separated antennas that view the same surface area. Classical InSAR is based on high coherence between two or more images. The output (interferogram) can show subtle changes with an accuracy of several millimeters to centimeters. Very little work has been done on measuring or identifying the changes in dunes using InSAR methods. The reason is that dunes tend to be less coherent than firm, stable, surfaces. This work aims to demonstrate how interferometric decorrelation can be used for identifying dune instability. We hypothesize and demonstrate that the loss of radar coherence over time on dunes can be used as an indication of the dune's instability. When SAR images are acquired at sufficiently close intervals one can measure the time it takes to lose coherence and associate this time with geomorphic stability. To achieve our goals, the coherence change detection method was used, in order to identify dune stability or instability and the dune activity level. The Nitzanim-Ashdod coastal dunes along the Mediterranean, 40 km south of Tel-Aviv, Israel, were chosen as a case study. The dunes in this area are of

  17. Groundwater variables and vegetation in dune slacks

    NARCIS (Netherlands)

    Lammerts, E.J.; Maas, C.; Grootjans, A.P.

    Basiphilous pioneer plant communities, influenced by phreatic groundwater, are endangered in The Netherlands. In dune slacks of the Dutch Wadden Sea islands, their area has also declined, though they still occur fairly frequently. For purposes of nature conservancy it is important to know how to

  18. Coastal protection policy in the Netherlands

    NARCIS (Netherlands)

    Verhagen, H.J.

    1990-01-01

    The 350 km long Dutch coast along the North Sea is characterized by alternating coastal stretches of accretion and erosion resp. resulting in seaward and landward displacement retreats of the shoreline. Places of accretion and erosion also vary in time. Behind the dunes are low lying polders (very

  19. The effects of changing wind regimes on the development of blowouts in the coastal dunes of The Netherlands

    NARCIS (Netherlands)

    Jungerius, P.D.; Witter, J.V.; van Boxel, J.H.

    1991-01-01

    Blowouts are the main features of aeolian activity in many dune areas. To assess the impact of future climatic change on the geomorphological processes prevailing in a dune landscape it is essential to understand blowout formation and identify the meteorological parameters which are important. The

  20. Quantification of Dune Response over the Course of a 6-Day Nor'Easter, Outer Banks, NC

    Science.gov (United States)

    Brodie, K. L.; Spore, N.; Swann, C.

    2014-12-01

    The amount and type of foredune morphologic change during a storm event primarily scales with the level of inundation during that event. Specifically, external hydrodynamic forcing (total water level) can be compared with antecedent beach and foredune morphology to predict an impact regime that relates to the type of expected morphologic evolution of the system. For example, when total water levels are above the dune toe, but below the dune crest, the impact regime is classified as "collision" and the expected morphology response is slumping or scarping of the dune face. While the amount of dune retreat scales largely with the duration of wave attack to the dune face, characteristics of the dune other than its crest or toe elevation may also enhance or impede rates of morphologic change. The aftermath of Hurricane Sandy provided a unique opportunity to observe alongshore variations in dune response to a 6-day Nor'Easter (Hs >4 m in 6 m depth), as a variety of dunes were constructed (or not) by individual home owners in preparation for the winter storm season. Daily terrestrial lidar scans were conducted along 20 km of coastline in Duck, NC using Coastal Lidar And Radar Imaging System (CLARIS) during the first dune collision event following Sandy. Foredunes were grouped by their pre-storm form (e.g. vegetated, pushed, scarped, etc) using automated feature extraction tools based on surface curvature and slope, and daily rates of morphologic volume change were calculated. The highest dune retreat rates were focused along a 1.5 km region where cross-shore erosion of recently pushed, un-vegetated dunes reached 2 m/day. Variations in dune response were analyzed in relation to their pre-storm morphology, with care taken to normalize for alongshore variations in hydrodynamic forcing. Ongoing research is focused on identifying specific metrics that can be easily extracted from topographic DEMs to aid in dune retreat predictions.

  1. Structure of Mesozooplankton Communities in the Coastal Waters of Morocco

    Science.gov (United States)

    Lidvanov, V. V.; Grabko, O. G.; Kukuev, E. I.; Korolkova, T. G.

    2018-03-01

    Mero- and holoplanktonic organisms from 23 large taxa have been detected in the coastal waters of Morocco. Seven Cladocera species and 164 Copepoda species were identified. Copepod fauna mostly consisted of oceanic epipelagic widely tropical species, but the constant species group (frequency of occurrence over 50%) included neritic and neritic-oceanic widely tropical species. The neritic community that formed a biotopic association with coastal upwelling waters and the distant-neritic community associated with Canary Current waters were the two major communities detected. The former community was characterized by a high abundance and biomass (5700 ind./m3 and 260 mg/m3) and predominance of neritic species. The trophic structure was dominated by thin filter feeders, mixed-food consumers, and small grabbers; the species structure was dominated by Paracalanus indicus, Acartia clausi, and Oncaea curta; the indices of species diversity (3.07 bit/ind.) and evenness (0.63) were relatively low. The latter community was characterized by low abundance and biomass (1150 ind./m3 and 90 mg/m3); variable biotopic, trophic, and species structure; and higher Shannon indices (3.99 bit/ind.) and Pielou (0.75). Seasonal variation of the abundance of organisms was not detected in the communities. Anomalous mesozooplankton states were observed in summer 1998 and winter 1998-1999.

  2. Oceanic rafting by a coastal community.

    Science.gov (United States)

    Fraser, Ceridwen I; Nikula, Raisa; Waters, Jonathan M

    2011-03-07

    Oceanic rafting is thought to play a fundamental role in assembling the biological communities of isolated coastal ecosystems. Direct observations of this key ecological and evolutionary process are, however, critically lacking. The importance of macroalgal rafting as a dispersal mechanism has remained uncertain, largely owing to lack of knowledge about the capacity of fauna to survive long voyages at sea and successfully make landfall and establish. Here, we directly document the rafting of a diverse assemblage of intertidal organisms across several hundred kilometres of open ocean, from the subantarctic to mainland New Zealand. Multispecies analyses using phylogeographic and ecological data indicate that 10 epifaunal invertebrate species rafted on six large bull kelp specimens for several weeks from the subantarctic Auckland and/or Snares Islands to the Otago coast of New Zealand, a minimum distance of some 400-600 km. These genetic data are the first to demonstrate that passive rafting can enable simultaneous trans-oceanic transport and landfall of numerous coastal taxa.

  3. Microbial Community Response to Terrestrially Derived Dissolved Organic Matter in the Coastal Arctic

    Directory of Open Access Journals (Sweden)

    Rachel E. Sipler

    2017-06-01

    Full Text Available Warming at nearly twice the global rate, higher than average air temperatures are the new ‘normal’ for Arctic ecosystems. This rise in temperature has triggered hydrological and geochemical changes that increasingly release carbon-rich water into the coastal ocean via increased riverine discharge, coastal erosion, and the thawing of the semi-permanent permafrost ubiquitous in the region. To determine the biogeochemical impacts of terrestrially derived dissolved organic matter (tDOM on marine ecosystems we compared the nutrient stocks and bacterial communities present under ice-covered and ice-free conditions, assessed the lability of Arctic tDOM to coastal microbial communities from the Chukchi Sea, and identified bacterial taxa that respond to rapid increases in tDOM. Once thought to be predominantly refractory, we found that ∼7% of dissolved organic carbon and ∼38% of dissolved organic nitrogen from tDOM was bioavailable to receiving marine microbial communities on short 4 – 6 day time scales. The addition of tDOM shifted bacterial community structure toward more copiotrophic taxa and away from more oligotrophic taxa. Although no single order was found to respond universally (positively or negatively to the tDOM addition, this study identified 20 indicator species as possible sentinels for increased tDOM. These data suggest the true ecological impact of tDOM will be widespread across many bacterial taxa and that shifts in coastal microbial community composition should be anticipated.

  4. State-space modeling indicates rapid invasion of an alien shrub in coastal dunes

    DEFF Research Database (Denmark)

    Damgaard, Christian Frølund; Nygaard, Bettina; Ejrnæs, Rasmus

    2011-01-01

    allows separation of process and sampling variance, thus enabling ecological predictions with a known degree of uncertainty. The method is applied for the invasive shrub Rosa rugosa (Japanese rose) in Danish fixed dunes. The probability of observing R. rugosa increased significantly from 0.18 to 0...

  5. Observations and analytical modeling of freshwater and rainwater lenses in coastal dune systems

    NARCIS (Netherlands)

    Stuijfzand, Pieter

    2016-01-01

    Observations are reported on (i) groundwater recharge rates under various types of vegetation as measured with megalysimeters in the dunes, (ii) freshwater lenses along the Dutch North Sea coast in the early 1900s, and (iii) rainwater lenses that develop on top of laterally migrating,

  6. Booming Sand Dunes

    Science.gov (United States)

    Vriend, Nathalie

    "Booming" sand dunes are able to produce low-frequency sound that resembles a pure note from a music instrument. The sound has a dominant audible frequency (70-105 Hz) and several higher harmonics and may be heard from far distances away. A natural or induced avalanche from a slip face of the booming dune triggers the emission that may last for several minutes. There are various references in travel literature to the phenomenon, but to date no scientific explanation covered all field observations. This thesis introduces a new physical model that describes the phenomenon of booming dunes. The waveguide model explains the selection of the booming frequency and the amplification of the sound in terms of constructive interference in a confined geometry. The frequency of the booming is a direct function of the dimensions and velocities in the waveguide. The higher harmonics are related to the higher modes of propagation in the waveguide. The experimental validation includes quantitative field research at the booming dunes of the Mojave Desert and Death Valley National Park. Microphone and geophone recordings of the acoustic and seismic emission show a variation of booming frequency in space and time. The analysis of the sensor data quantifies wave propagation characteristics such as speed, dispersion, and nonlinear effects and allows the distinction between the source mechanism of the booming and the booming itself. The migration of sand dunes results from a complicated interplay between dune building, wind regime, and precipitation. The morphological and morphodynamical characteristics of two field locations are analyzed with various geophysical techniques. Ground-penetrating radar images the subsurface structure of the dunes and reveal a natural, internal layering that is directly related to the history of dune migration. The seismic velocity increases abruptly with depth and gradually increases with downhill position due to compaction. Sand sampling shows local

  7. Vegetated dune morphodynamics during recent stabilization of the Mu Us dune field, north-central China

    Science.gov (United States)

    Xu, Zhiwei; Mason, Joseph A.; Lu, Huayu

    2015-01-01

    The response of dune fields to changing environmental conditions can be better understood by investigating how changing vegetation cover affects dune morphodynamics. Significant increases in vegetation and widespread dune stabilization over the years 2000-2012 are evident in high-resolution satellite imagery of the Mu Us dune field in north-central China, possibly a lagged response to changing wind strength and temperature since the 1970s. These trends provide an opportunity to study how dune morphology changes with increasing vegetation stabilization. Vegetation expansion occurs mainly by expansion of pre-existing patches in interdunes. As vegetation spreads from interdunes onto surrounding dunes, it modifies their shapes in competition with wind-driven sand movement, primarily in three ways: 1) vegetation anchoring horns of barchans transforms them to parabolic dunes; 2) vegetation colonizes stoss faces of barchan and transverse dunes, resulting in lower dune height and an elongated stoss face, with shortening of barchan horns; and 3) on transverse dunes, the lee face is fixed by plants that survive sand burial. Along each of these pathways of stabilization, dune morphology tends to change from more barchanoid to more parabolic forms, but that transformation is not always completed before full stabilization. Artificial stabilization leads to an extreme case of "frozen" barchans or transverse dunes with original shapes preserved by rapid establishment of vegetation. Observations in the Mu Us dune field emphasize the point that vegetation growth and aeolian sand transport not only respond to external factors such as climate but also interact with each other. For example, some barchans lose sand mass during vegetation fixation, and actually migrate faster as they become smaller, and vegetation growth on a barchan's lower stoss face may alter sand transport over the dune in a way that favors more rapid stabilization. Conceptual models were generalized for the

  8. Modeling river dune development and dune transition to upper stage plane bed

    NARCIS (Netherlands)

    Naqshband, Suleyman; van Duin, Olav; Ribberink, Jan S.; Hulscher, Suzanne J.M.H.

    2016-01-01

    Large asymmetric bedforms known as dunes commonly dominate the bed of sand rivers. Due to the turbulence generation over their stoss and lee sides, dunes are of central importance in predicting hydraulic roughness and water levels. During floods in steep alluvial rivers, dunes are observed to grow

  9. The evolution of Holocene coastal dunefields, Jutland, Denmark

    DEFF Research Database (Denmark)

    Clemmensen, Lars B; Murray, Andrew S.; Heinemeier, Jan

    2009-01-01

    Coastal dunefields have developed on the west coast of Jutland in Denmark over the past 5000 years. The dunefields are situated in a temperate climate zone with frequent high energy wind events. Dunefield development was characterized by repeated periods of transgressive dune formation punctuated...

  10. Observations regarding the movement of barchan sand dunes in the Nazca to Tanaca area of southern Peru

    Science.gov (United States)

    Parker Gay, S.

    1999-03-01

    Significant studies of sand dunes and sand movement made in coastal southern Peru in 1959-1961 [Gay, S.P., 1962. Origen, distribución y movimiento de las arenas eólicas en el área de Yauca a Palpa. Boletin de la Sociedad Geologica del Perú 37, 37-58] have never been published in the English language and consequently have never been referred to in the standard literature. These studies contain valuable information, not developed by later workers in this field, that may be of broad general interest. For example, using airphotos of barchan dunes and plotting the rates of movement vs. dune widths, the author quantified the deduction of Bagnold [Bagnold, R.A., 1941. The Physics of Blown Sand and Desert Dunes. Methuen, London.] that the speed of barchan movement is inversely proportional to barchan size (as characterized by height or width). This led to the conclusion that all barchans in a given dune field, regardless of size, sweep out approximately equal areas in equal times. Another conclusion was that collisions between smaller, overtaking dunes and larger dunes in front of them do not result in destruction or absorption of the smaller dunes if the collision is a `sideswipe'. The dunes simply merge into a compound dune for a time, and the smaller dune then moves on intact, i.e., passes, the larger dune, whilst retaining its approximate original size and shape. Another result of the 1959-1961 studies was a map that documents the Pacific coast beaches as the source of the sand ( Fig. 1), which is then blown inland through extensive dune fields of barchans and other dune forms in great clockwise-sweeping paths, to its final resting place in huge sand masses, sometimes called `sand seas' [Lancaster, N., 1995. Geomorphology of Desert Dunes. Routledge, London], at higher elevations 20 to 60 km from the coast. A minor, but nevertheless interesting, discovery was a small heavy mineral dune located directly in the lee of a large barchan, evidently formed by the winnowing

  11. Actions Environmental Sustainability Measures for Producers and Local Communities in a Coastal Area

    Directory of Open Access Journals (Sweden)

    María Elena Zequeira-Álvarez

    2017-06-01

    Full Text Available In this work, the area of study is defined as the producers and communities of the northern coastal zone, up to the 5-meter level curve of the province of Camagüey, Cuba. It is composed of four municipalities and is very rich in natural values but also identifies itself as a very fragile ecosystem. The methodological procedure consists of three stages that respond to their respective objectives: General characteristics of the study area, environmental problems in the area of study and general measures of sustainability for producers and coastal communities, The general objective of the work is to propose general measures of Environmental sustainability for producers and local communities in the northern coastal zone of Camagüey, Cuba in order to contribute to the use and conservation of the ecosystem. These are aimed at the producers and settlers of the study area but may be interesting for other ecosystems.

  12. Spatio-temporal variability in accretion and erosion of coastal foredunes in the Netherlands: regional climate and local topography.

    Science.gov (United States)

    Keijsers, Joep G S; Poortinga, Ate; Riksen, Michel J P M; Maroulis, Jerry

    2014-01-01

    Depending on the amount of aeolian sediment input and dune erosion, dune size and morphology change over time. Since coastal foredunes play an important role in the Dutch coastal defence, it is important to have good insight in the main factors that control these changes. In this paper the temporal variations in foredune erosion and accretion were studied in relation to proxies for aeolian transport potential and storminess using yearly elevation measurements from 1965 to 2012 for six sections of the Dutch coast. Longshore differences in the relative impacts of erosion and accretion were examined in relation to local beach width. The results show that temporal variability in foredune accretion and erosion is highest in narrow beach sections. Here, dune erosion alternates with accretion, with variability displaying strong correlations with yearly values of storminess (maximum sea levels). In wider beach sections, dune erosion is less frequent, with lower temporal variability and stronger correlations with time series of transport potential. In erosion dominated years, eroded volumes decrease from narrow to wider beaches. When accretion dominates, dune-volume changes are relatively constant alongshore. Dune erosion is therefore suggested to control spatial variability in dune-volume changes. On a scale of decades, the volume of foredunes tends to increase more on wider beaches. However, where widths exceed 200 to 300 m, this trend is no longer observed.

  13. Mars Global Digital Dune Database (MGD3): Global dune distribution and wind pattern observations

    Science.gov (United States)

    Hayward, Rosalyn K.; Fenton, Lori; Titus, Timothy N.

    2014-01-01

    The Mars Global Digital Dune Database (MGD3) is complete and now extends from 90°N to 90°S latitude. The recently released south pole (SP) portion (MC-30) of MGD3 adds ∼60,000 km2 of medium to large-size dark dune fields and ∼15,000 km2 of sand deposits and smaller dune fields to the previously released equatorial (EQ, ∼70,000 km2), and north pole (NP, ∼845,000 km2) portions of the database, bringing the global total to ∼975,000 km2. Nearly all NP dunes are part of large sand seas, while the majority of EQ and SP dune fields are individual dune fields located in craters. Despite the differences between Mars and Earth, their dune and dune field morphologies are strikingly similar. Bullseye dune fields, named for their concentric ring pattern, are the exception, possibly owing their distinctive appearance to winds that are unique to the crater environment. Ground-based wind directions are derived from slipface (SF) orientation and dune centroid azimuth (DCA), a measure of the relative location of a dune field inside a crater. SF and DCA often preserve evidence of different wind directions, suggesting the importance of local, topographically influenced winds. In general however, ground-based wind directions are broadly consistent with expected global patterns, such as polar easterlies. Intriguingly, between 40°S and 80°S latitude both SF and DCA preserve their strongest, though different, dominant wind direction, with transport toward the west and east for SF-derived winds and toward the north and west for DCA-derived winds.

  14. Ethnotaxonomical Study of Mole Crab (Crustacea:Hippoidea on Coastal Community of Cilacap

    Directory of Open Access Journals (Sweden)

    Dian Bhagawati

    2016-09-01

    Full Text Available Local wisdom is a cultural heritage that needs to be preserved. The Cilacap’s coastal communities have traditional taxonomy knowledge that hasn’t been informed, especially about mole crab. This study aimed to explore the ethnotaxonomy knowledge of sand crabs (Crustacea: Hippoidea in Widarapayung coastal communities. The purposive snowball sampling was used for the method, followed by observation and semi-structured interviews with 30 respondents. Data were analyzed descriptively based on observations and interviews. The results showed that the coastal communities in Widarapayung tourist areas could be divided into five groups, namely catchers, collectors, processors, traders, and consumers. The catcher was able to recognize and describe three types of sand crabs based on the shape of the body and their catchment areas. Captured crabs had the local name of ‘yutuk jambe’ (Emerita emeritus Linnaeus 1767, the appellation was based on carapace shape that resembled the shape of areca fruit; ‘Yutuk bathok’ (Hippa adactyla Fabricius 1787, had the carapace shape resembling a coconut shell, and ‘yutuk Kethek’ (Albunea symmysta Linnaeus 1758, had ornaments on the carapace surface similar with a monkey face, there were dense setae on the edge of the carapace, spiny long antennas and aggressively pinch when captured. The knowledge and skills of sand crabs classification and local name entitlement acquired by the people were in accordance with the Berlin’s model. How to CiteBhagawati, D., Anggoro, S., Zainuri, M. & Sya’rani, L. (2016. Ethnotaxonomical Study of Mole Crab (Crustacea:Hippoidea on Coastal Community of Cilacap. Biosaintifika: Journal of Biology & Biology Education, 8(2, 222-230.

  15. Inside ProtoDune

    CERN Multimedia

    Brice, Maximilien

    2017-01-01

    The protoDUNE experimental program is designed to test and validate the technologies and design that will be applied to the construction of the DUNE Far Detector at the Sanford Underground Research Facility (SURF). The protoDUNE detectors will be run in a dedicated beam line at the CERN SPS accelerator complex. The rate and volume of data produced by these detectors will be substantial and will require extensive system design and integration effort. As of Fall 2015, "protoDUNE" is the official name for the two apparatuses to be used in CERN beam test: single-phase and dual-phase LArTPC detectors. Each received a formal CERN experiment designation: NP02 for the dual-phase detector. NP04 for single-phase detector.

  16. 50 Years of coastal erosion analysis: A new methodological approach.

    Science.gov (United States)

    Prieto Campos, Antonio; Diaz Cuevas, Pilar; Ojeda zujar, Jose; Guisado-Pintado, Emilia

    2017-04-01

    Coasts over the world have been subjected to increased anthropogenic pressures which combined with natural hazards impacts (storm events, rising sea-levels) have led to strong erosion problems with negative impacts on the economy and the safety of coastal communities. The Andalusian coast (South Spain) is a renowned global tourist destination. In the past decades a deep transformation in the economic model led to significant land use changes: strong regulation of rivers, urbanisation and occupation of dunes, among others. As a result irreversible transformations on the coastline, from the aggressive urbanisation undertaken, are now to be faced by local authorities and suffered by locals and visitors. Moreover, the expected impacts derived from the climate change aggravated by anthropic activities emphasises the need for tools that facilitates decision making for a sustainable coastal management. In this contribution a homogeneous (only a proxy and one photointerpreter) methodology is proposed for the calculation of coastal erosion rates of exposed beaches in Andalusia (640 km) through the use of detailed series (1:2500) of open source orthophotographies for the period (1956-1977-2001-2011). The outstanding combination of the traditional software DSAS (Digital Shoreline Analysis System) with a spatial database (PostgreSQL) which integrates the resulting erosion rates with related coastal thematic information (geomorphology, presence of engineering infrastructures, dunes and ecosystems) enhances the capacity of analysis and exploitation. Further, the homogeneity of the method used allows the comparison of the results among years in a highly diverse coast, with both Mediterranean and Atlantic façades. The novelty development and integration of a PostgreSQL/Postgis database facilitates the exploitation of the results by the user (for instance by relating calculated rates with other thematic information as geomorphology of the coast or the presence of a dune field on

  17. Seasonal geomorphic processes and rates of sand movement at Mount Baldy dune in Indiana, USA

    Science.gov (United States)

    Kilibarda, Zoran; Kilibarda, Vesna

    2016-12-01

    Winds are very strong, frequent, and have high energy (annual DP ∼800 VU) along the southern shores of Lake Michigan, allowing the coexistence of fixed and active dunes. Six years (2007-13) of monitoring Mount Baldy in the Indiana Dunes National Lakeshore reveals that this is the most active coastal dune in the Great Lakes region. This paper documents aeolian processes and changes in the dune's morphology that occur temporarily, following storms, or seasonally, due to weather (climate) variations. Most of the sand transport in this area takes place during strong storms with gale force (>17.5 m/s) winds, which occur in the autumn and winter months. A single storm, such as the October 28-31, 2013 event, can contribute 25% of the annual sand transport and dune movement inland. In its most active year (June 1, 2011 through May 31, 2012), Mount Baldy moved inland on average 4.34 m, with a maximum of 6.52 m along the blowout's axis (155° azimuth). During this particularly active season, there were six storms with sustained gale force winds, winter air temperatures were warmer than average, and shelf ice on Lake Michigan lasted only one day. The dune is least active during the summer season, when the winds are weakest. The late fall and winter winds are the strongest. But in a typical year, most of the dune's advance inland takes place during the spring thaw when sand is released from over-steepened and lumpy slip face, allowing it to avalanche to the toe of the slip face. However, with a warming air temperatures, a reduction in the duration of winter shelf ice, and rising Lake Michigan levels, the annual rates of sand transport and dune movement may increase. The recent Mount Baldy management strategy, which includes planting vegetation and installing wind barriers on the dune's stoss side in an effort to fix the dune and stop its further movement inland, may potentially cause the destruction of the mobile sand, open dune habitat, resulting in the extinction of rare

  18. Dune erosion above revetments

    NARCIS (Netherlands)

    Van Thiel de Vries, J.S.M.

    2012-01-01

    In a situation with a narrow dune, the dune base can be protected with a revetment to reduce dune erosion during extreme events. To quantify the effects of a revetment on storm impact, the functionality of the numerical storm impact model XBeach (Roelvink et al., 2009) is extended to account for the

  19. Temporal and Spatial Diversity of Bacterial Communities in Coastal Waters of the South China Sea

    Science.gov (United States)

    Du, Jikun; Xiao, Kai; Li, Li; Ding, Xian; Liu, Helu; Lu, Yongjun; Zhou, Shining

    2013-01-01

    Bacteria are recognized as important drivers of biogeochemical processes in all aquatic ecosystems. Temporal and geographical patterns in ocean bacterial communities have been observed in many studies, but the temporal and spatial patterns in the bacterial communities from the South China Sea remained unexplored. To determine the spatiotemporal patterns, we generated 16S rRNA datasets for 15 samples collected from the five regularly distributed sites of the South China Sea in three seasons (spring, summer, winter). A total of 491 representative sequences were analyzed by MOTHUR, yielding 282 operational taxonomic units (OTUs) grouped at 97% stringency. Significant temporal variations of bacterial diversity were observed. Richness and diversity indices indicated that summer samples were the most diverse. The main bacterial group in spring and summer samples was Alphaproteobacteria, followed by Cyanobacteria and Gammaproteobacteria, whereas Cyanobacteria dominated the winter samples. Spatial patterns in the samples were observed that samples collected from the coastal (D151, D221) waters and offshore (D157, D1512, D224) waters clustered separately, the coastal samples harbored more diverse bacterial communities. However, the temporal pattern of the coastal site D151 was contrary to that of the coastal site D221. The LIBSHUFF statistics revealed noticeable differences among the spring, summer and winter libraries collected at five sites. The UPGMA tree showed there were temporal and spatial heterogeneity of bacterial community composition in coastal waters of the South China Sea. The water salinity (P=0.001) contributed significantly to the bacteria-environment relationship. Our results revealed that bacterial community structures were influenced by environmental factors and community-level changes in 16S-based diversity were better explained by spatial patterns than by temporal patterns. PMID:23785512

  20. Laboratory studies of dune sand for the use of construction industry in Sri Lanka

    Science.gov (United States)

    de Silva Jayawardena, Upali; Wijesuriya, Roshan; Abayaweera, Gayan; Viduranga, Tharaka

    2015-04-01

    With the increase of the annual sand demand for the construction industry the excessive excavation of river sand is becoming a serious environmental problem in Sri Lanka. Therefore, it is necessary to explore the possibility for an alternative to stop or at least to minimize river sand mining activities. Dune sand is one of the available alternative materials to be considered instead of river sand in the country. Large quantities of sand dunes occur mainly along the NW and SE coastal belt which belong to very low rainfall Dry Zone coasts. The height of dune deposits, vary from 1m to about 30 meters above sea level. The objective of this paper is to indicate some studies and facts on the dune sand deposits of Sri Lanka. Laboratory studies were carried out for visual observations and physical properties at the initial stage and then a number of tests were carried out according to ASTM standards to obtain the compressive strength of concrete cylinders and mortar cubes mixing dune sand and river sand in different percentages keeping a constant water cement ratio. Next the water cement ratio was changed for constant dune sand and river sand proportion. Microscopic analysis shows that the dune sand consist of 95 % of quartz and 5 % of garnet, feldspar, illmenite and other heavy minerals with clay, fine dust, fine shell fragments and organic matters. Grains are sub-rounded to angular and tabular shapes. The grain sizes vary from fine to medium size of sand with silt. The degree of sorting and particle size observed with dune sands are more suited with the requirement of fine aggregates in the construction industry. The test result indicates that dune sand could be effectively used in construction work without sieving and it is ideal for wall plastering due to its'-uniformity. It could also be effectively used in concrete and in mortars mixing with river sand. The best mixing ratio is 75% dune sand and 25% river sand as the fine aggregate of concrete. For mortar the mixing

  1. Suppression of hyphal growth of soil-borne fungi by dune soils from vigorous and declining stands of Ammophila arenaria

    NARCIS (Netherlands)

    De Boer, W.; Klein Gunnewiek, P.J.A.; Woldendorp, J.W.

    1998-01-01

    A study was carried out to determine whether expansion of marram-grass stands (Ammophila arenaria (L.) Link) on acidic inner Dutch coastal dunes was caused by suppressiveness of soils from these stands against three potential pathogenic fungi of marram grass, namely Fusarium culmorum (W. G. Sm.)

  2. Spatial distribution of microbial communities associated with dune landform in the Gurbantunggut Desert, China.

    Science.gov (United States)

    Liu, Ruyin; Li, Ke; Zhang, Hongxun; Zhu, Junge; Joshi, DevRaj

    2014-11-01

    The microbial community compositions and potential ammonia oxidation in the topsoil at different positions of sand dune (stoss slope, crest, lee slope, and interdune) from the Gurbantunggut Desert, the largest semi-fixed desert in China, were investigated using several molecular methods. Actinobacteria and Proteobacteria (especially Alphaproteobacteria) were commonly the dominant taxa across all soil samples. Bacterial communities were similar in soils collected from the stoss slopes and interdunes (HC-BSCs, biological soil crusts with a high abundance of cyanobacteria), containing more abundant cyanobacterial populations (16.9-24.5%) than those (0.2-0.7% of Cyanobacteria) in the crests and lee slopes (LC-BSCs, biological soil crusts with a low abundance of cyanobacteria). The Cyanobacteria were mainly composed of Microcoleus spp., and quantitative PCR analysis revealed that 16S rRNA gene copy numbers of Cyanobacteria (especially genus Microcoleus) were at least two orders of magnitude higher in HC-BSCs than in LC-BSCs. Heterotrophic Geodermatophilus spp. frequently occurred in HC-BSCs (2.5-8.0%), whereas genera Arthrobacter, Bacillus, and Segetibacter were significantly abundant in LC-BSC communities. By comparison, the desert archaeal communities were less complex, and were dominated by Nitrososphaera spp. The amoA gene abundance of ammonia-oxidizing archaea (AOA) was higher than that of ammonia-oxidizing bacteria (AOB) in all soil samples, particularly in the interdunal soils (10(6)-10(8) archaeal amoA gene copies per gram dry soil), indicating that AOA possibly dominate the ammonia oxidation at the interdunes.

  3. Diet of the lizard Liolaemus occipitalis in the coastal sand dunes of southern Brazil (Squamata-Liolaemidae

    Directory of Open Access Journals (Sweden)

    L. Verrastro

    Full Text Available Knowledge of a species’ diet provides important information on adaptation and the relationship between the organism and its environment. The genus Liolaemus occurs in the southern region of South America and is an excellent model to investigate the adaptive processes of vertebrate ecology in ecosystems of this region of the world. Liolaemus occipitalis is an endangered species that inhabits the coastal sand dunes of southern Brazil. This species is the most abundant vertebrate in this environment, and it presents unique adaptation characteristics to the restinga environment. The present study analyzed this lizard’s diet to verify similarities or differences between this species and other species of the same genus. Specimens were collected monthly from January 1996 to December 1997. The number of items, frequency of occurrence and volume of each prey taxon were determined. Arthropods were identified to the order level, and plant material was identified as flower, fruit, seed and leaves. Variations in the diet of males and females, adults and juveniles and seasons were also analyzed. The data indicate that Liolaemus occipitalis is a generalist, “sit-and-wait” or ambush predator as well as omnivorous, feeding on both arthropods and plant material. Significant ontogenetic differences were verified. Juveniles are more carnivorous, and the intake of plant material increases with size and age. Seasonal differences in diet composition were also observed. In the spring, arthropod and plant materials were more diversified and, therefore, consumed more often.

  4. Diet of the lizard Liolaemus occipitalis in the coastal sand dunes of southern Brazil (Squamata-Liolaemidae).

    Science.gov (United States)

    Verrastro, L; Ely, I

    2015-05-01

    Knowledge of a species' diet provides important information on adaptation and the relationship between the organism and its environment. The genus Liolaemus occurs in the southern region of South America and is an excellent model to investigate the adaptive processes of vertebrate ecology in ecosystems of this region of the world. Liolaemus occipitalis is an endangered species that inhabits the coastal sand dunes of southern Brazil. This species is the most abundant vertebrate in this environment, and it presents unique adaptation characteristics to the restinga environment. The present study analyzed this lizard's diet to verify similarities or differences between this species and other species of the same genus. Specimens were collected monthly from January 1996 to December 1997. The number of items, frequency of occurrence and volume of each prey taxon were determined. Arthropods were identified to the order level, and plant material was identified as flower, fruit, seed and leaves. Variations in the diet of males and females, adults and juveniles and seasons were also analyzed. The data indicate that Liolaemus occipitalis is a generalist, "sit-and-wait" or ambush predator as well as omnivorous, feeding on both arthropods and plant material. Significant ontogenetic differences were verified. Juveniles are more carnivorous, and the intake of plant material increases with size and age. Seasonal differences in diet composition were also observed. In the spring, arthropod and plant materials were more diversified and, therefore, consumed more often.

  5. Resilience from coastal protection.

    Science.gov (United States)

    Ewing, Lesley C

    2015-10-28

    Coastal areas are important residential, commercial and industrial areas; but coastal hazards can pose significant threats to these areas. Shoreline/coastal protection elements, both built structures such as breakwaters, seawalls and revetments, as well as natural features such as beaches, reefs and wetlands, are regular features of a coastal community and are important for community safety and development. These protection structures provide a range of resilience to coastal communities. During and after disasters, they help to minimize damages and support recovery; during non-disaster times, the values from shoreline elements shift from the narrow focus on protection. Most coastal communities have limited land and resources and few can dedicate scarce resources solely for protection. Values from shore protection can and should expand to include environmental, economic and social/cultural values. This paper discusses the key aspects of shoreline protection that influence effective community resilience and protection from disasters. This paper also presents ways that the economic, environmental and social/cultural values of shore protection can be evaluated and quantified. It presents the Coastal Community Hazard Protection Resilience (CCHPR) Index for evaluating the resilience capacity to coastal communities from various protection schemes and demonstrates the use of this Index for an urban beach in San Francisco, CA, USA. © 2015 The Author(s).

  6. A socioeconomic assessment of climate change-enhanced coastal storm hazards in the U.S. Pacific Northwest

    Science.gov (United States)

    Baron, H. M.; Ruggiero, P.; Harris, E.

    2010-12-01

    Every winter, coastal communities in the U.S. Pacific Northwest are at risk to coastal change hazards caused by extreme storm events. These storms have the potential to erode large portions of the primary foredune that may be a community’s only barrier from the ocean. Furthermore, the frequency and magnitude of significant erosion events appears to be increasing, likely due to climate-related processes such as sea level rise and increases in storm wave heights. To reduce risks posed by winter storms, it is not only important to determine the impending physical impacts but it is also necessary to explore the vulnerability of the social-ecological system in the context of these hazards. Here we assess the exposure to both annually occurring and extreme storm events at various planning timelines using a methodology that incorporates the effect of a variable and changing climate on future total water levels. To do this, we have developed a suite of climate change scenarios involving a range of projections for the wave climate, global sea level rise, and the occurrence of El Niño events through 2100. Simple geometric models are then used to conservatively determine the extent of erosion that may occur for a given combination of these climatic factors. We integrate the physical hazards with socioeconomic data using a geographic information system (GIS) in order to quantify societal vulnerability, characterized by the exposure and sensitivity of a community, which is based on the distribution of people, property, and resources. Here we focus on a 14 km stretch of dune-backed coast in northwest Oregon, from Cascade Head to Cape Kiwanda—the location of two communities that, historically, have experienced problematic storm-induced coastal change, Pacific City and Neskowin. Although both of these communities have similar exposure to coastal change hazards at the present, Neskowin is more than twice as sensitive to erosion because almost all of its residents and community

  7. Hurricane Isaac: observations and analysis of coastal change

    Science.gov (United States)

    Guy, Kristy K.; Stockdon, Hilary F.; Plant, Nathaniel G.; Doran, Kara S.; Morgan, Karen L.M.

    2013-01-01

    Understanding storm-induced coastal change and forecasting these changes require knowledge of the physical processes associated with a storm and the geomorphology of the impacted coastline. The primary physical process of interest is sediment transport that is driven by waves, currents, and storm surge associated with storms. Storm surge, which is the rise in water level due to the wind, barometric pressure, and other factors, allows both waves and currents to impact parts of the coast not normally exposed to these processes. Coastal geomorphology reflects the coastal changes associated with extreme-storm processes. Relevant geomorphic variables that are observable before and after storms include sand dune elevation, beach width, shoreline position, sediment grain size, and foreshore beach slope. These variables, in addition to hydrodynamic processes, can be used to quantify coastal change and are used to predict coastal vulnerability to storms (Stockdon and others, 2007). The U.S. Geological Survey (USGS) National Assessment of Coastal Change Hazards (NACCH) project (http://coastal.er.usgs.gov/national-assessment/) provides hazard information to those concerned about the Nation’s coastlines, including residents of coastal areas, government agencies responsible for coastal management, and coastal researchers. Extreme-storm research is a component of the NACCH project (http://coastal.er.usgs.gov/hurricanes/) that includes development of predictive understanding, vulnerability assessments using models, and updated observations in response to specific storm events. In particular, observations were made to determine morphological changes associated with Hurricane Isaac, which made landfall in the United States first at Southwest Pass, at the mouth of the Mississippi River, at 0000 August 29, 2012 UTC (Coordinated Universal Time) and again, 8 hours later, west of Port Fourchon, Louisiana (Berg, 2013). Methods of observation included oblique aerial photography

  8. Understanding river dune splitting through flume experiments and analysis of a dune evolution model

    NARCIS (Netherlands)

    Warmink, Jord Jurriaan; Dohmen-Janssen, Catarine M.; Lansink, Jord; Naqshband, Suleyman; van Duin, Olav; Paarlberg, Andries; Termes, A.P.P.; Hulscher, Suzanne J.M.H.

    2014-01-01

    Forecasts of water level during river floods require accurate predictions of the evolution of river dune dimensions, because the hydraulic roughness of the main channel is largely determined by the bed morphology. River dune dimensions are controlled by processes like merging and splitting of dunes.

  9. Persistent differences between coastal and offshore kelp forest communities in a warming Gulf of Maine.

    Directory of Open Access Journals (Sweden)

    Jon D Witman

    Full Text Available Kelp forests provide important ecosystem services, yet coastal kelp communities are increasingly altered by anthropogenic impacts. Kelp forests in remote, offshore locations may provide an informative contrast due to reduced impacts from local stressors. We tested the hypothesis that shallow kelp assemblages (12-15 m depth and associated fish and benthic communities in the coastal southwest Gulf of Maine (GOM differed significantly from sites on Cashes Ledge, 145 km offshore by sampling five coastal and three offshore sites at 43.0 +/- 0.07° N latitude. Offshore sites on Cashes Ledge supported the greatest density (47.8 plants m2 and standing crop biomass (5.5 kg m2 fresh weight of the foundation species Saccharina latissima kelp at this depth in the Western North Atlantic. Offshore densities of S. latissima were over 150 times greater than at coastal sites, with similar but lower magnitude trends for congeneric S. digitata. Despite these differences, S. latissima underwent a significant 36.2% decrease between 1987 and 2015 on Cashes Ledge, concurrent with a rapid warming of the GOM and invasion by the kelp-encrusting bryozoan Membranipora membranacea. In contrast to kelp, the invasive red alga Dasysiphonia japonica was significantly more abundant at coastal sites, suggesting light or dispersal limitation offshore. Spatial differences in fish abundance mirrored those of kelp, as the average biomass of all fish on Cashes Ledge was 305 times greater than at the coastal sites. Remote video censuses of cod (Gadus morhua, cunner (Tautaogolabrus adspersus, and pollock (Pollachius virens corroborated these findings. Understory benthic communities also differed between regions, with greater abundance of sessile invertebrates offshore. Populations of kelp-consuming sea urchins Stronglyocentrotus droebachiensis, were virtually absent from Cashes Ledge while small urchins were abundant onshore, suggesting recruitment limitation offshore. Despite

  10. Persistent differences between coastal and offshore kelp forest communities in a warming Gulf of Maine.

    Science.gov (United States)

    Witman, Jon D; Lamb, Robert W

    2018-01-01

    Kelp forests provide important ecosystem services, yet coastal kelp communities are increasingly altered by anthropogenic impacts. Kelp forests in remote, offshore locations may provide an informative contrast due to reduced impacts from local stressors. We tested the hypothesis that shallow kelp assemblages (12-15 m depth) and associated fish and benthic communities in the coastal southwest Gulf of Maine (GOM) differed significantly from sites on Cashes Ledge, 145 km offshore by sampling five coastal and three offshore sites at 43.0 +/- 0.07° N latitude. Offshore sites on Cashes Ledge supported the greatest density (47.8 plants m2) and standing crop biomass (5.5 kg m2 fresh weight) of the foundation species Saccharina latissima kelp at this depth in the Western North Atlantic. Offshore densities of S. latissima were over 150 times greater than at coastal sites, with similar but lower magnitude trends for congeneric S. digitata. Despite these differences, S. latissima underwent a significant 36.2% decrease between 1987 and 2015 on Cashes Ledge, concurrent with a rapid warming of the GOM and invasion by the kelp-encrusting bryozoan Membranipora membranacea. In contrast to kelp, the invasive red alga Dasysiphonia japonica was significantly more abundant at coastal sites, suggesting light or dispersal limitation offshore. Spatial differences in fish abundance mirrored those of kelp, as the average biomass of all fish on Cashes Ledge was 305 times greater than at the coastal sites. Remote video censuses of cod (Gadus morhua), cunner (Tautaogolabrus adspersus), and pollock (Pollachius virens) corroborated these findings. Understory benthic communities also differed between regions, with greater abundance of sessile invertebrates offshore. Populations of kelp-consuming sea urchins Stronglyocentrotus droebachiensis, were virtually absent from Cashes Ledge while small urchins were abundant onshore, suggesting recruitment limitation offshore. Despite widespread warming of

  11. The effects of coastal development on sponge abundance, diversity, and community composition on Jamaican coral reefs.

    Science.gov (United States)

    Stubler, Amber D; Duckworth, Alan R; Peterson, Bradley J

    2015-07-15

    Over the past decade, development along the northern coast of Jamaica has accelerated, resulting in elevated levels of sedimentation on adjacent reefs. To understand the effects of this development on sponge community dynamics, we conducted surveys at three locations with varying degrees of adjacent coastal development to quantify species richness, abundance and diversity at two depths (8-10 m and 15-18 m). Sediment accumulation rate, total suspended solids and other water quality parameters were also quantified. The sponge community at the location with the least coastal development and anthropogenic influence was often significantly different from the other two locations, and exhibited higher sponge abundance, richness, and diversity. Sponge community composition and size distribution were statistically different among locations. This study provides correlative evidence that coastal development affects aspects of sponge community ecology, although the precise mechanisms are still unclear. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Macrobenthic community structure response to coastal hypoxia off Southeastern Arabian sea

    Digital Repository Service at National Institute of Oceanography (India)

    Ingole, B.S.; Periasamy, R.; De, K.

    occurrence of coastal hypoxia condition (30 to 100 m depth) and normoxic bottom waters over the Southeastern Arabian Sea (SEAS). The macrofaunal communities patterns were analyzed by using various statistical methods (e.g. rank correlation, hierarchical...

  13. Stability of isolated Barchan dunes

    Science.gov (United States)

    Fourrière, Antoine; Charru, François

    2010-11-01

    When sand grains are entrained by an air flow over a non-erodible ground, or with limited sediment supply from the bed, they form isolated dunes showing a remarkable crescentic shape with horns pointing downstream. These dunes, known as Barchan dunes, are commonly observed in deserts, with height of a few meters and velocity of a few meters per year (Bagnold 1941). These dunes also exist under water, at a much smaller, centimetric size (Franklin & Charru 2010). Their striking stability properties are not well understood yet. Two phenomena are likely to be involved in this stability: (i) relaxation effects of the sand flux which increases from the dune foot up to the crest, related to grain inertia or deposition, and (ii) a small transverse sand flux due to slope effects and the divergence of the streamlines of the fluid flow. We reproduced aqueous Barchan dunes in a channel, and studied their geometrical and dynamic properties (in particular their shape, velocity, minimum size, and rate of erosion). Using coloured glass beads (see the figure), we were then able to measure the particle flux over the whole dune surface. We will discuss the stability of these dunes in the light of our measurements.

  14. Sand mining impacts on long-term dune erosion in southern Monterey Bay

    Science.gov (United States)

    Thornton, E.B.; Sallenger, Abby; Sesto, Juan Conforto; Egley, L.; McGee, Timothy; Parsons, Rost

    2006-01-01

    Southern Monterey Bay was the most intensively mined shoreline (with sand removed directly from the surf zone) in the U.S. during the period from 1906 until 1990, when the mines were closed following hypotheses that the mining caused coastal erosion. It is estimated that the yearly averaged amount of mined sand between 1940 and 1984 was 128,000 m3/yr, which is approximately 50% of the yearly average dune volume loss during this period. To assess the impact of sand mining, erosion rates along an 18 km range of shoreline during the times of intensive sand mining (1940–1990) are compared with the rates after sand mining ceased (1990–2004). Most of the shoreline is composed of unconsolidated sand with extensive sand dunes rising up to a height of 46 m, vulnerable to the erosive forces of storm waves. Erosion is defined here as a recession of the top edge of the dune. Recession was determined using stereo-photogrammetry, and LIDAR and GPS surveys. Long-term erosion rates vary from about 0.5 m/yr at Monterey to 1.5 m/yr in the middle of the range, and then decrease northward. Erosion events are episodic and occur when storm waves and high tides coincide, allowing swash to undercut the dune and resulting in permanent recession. Erosion appears to be correlated with the occurrence of El Niños. The calculated volume loss of the dune in southern Monterey Bay during the 1997–98 El Niño winter was 1,820,000 m3, which is almost seven times the historical annual mean dune erosion of 270,000 m3/yr. The alongshore variation in recession rates appears to be a function of the alongshore gradient in mean wave energy and depletions by sand mining. After cessation of sand mining in 1990, the erosion rates decreased at locations in the southern end of the bay but have not significantly changed at other locations.

  15. Hydrodynamic Based Decision Making Framework for Impact Assessment of Extreme Storm Events on Coastal Communities

    Science.gov (United States)

    Nazari, R.; Miller, K.; Hurler, C.

    2015-12-01

    Coastal and inland flooding has been a problematic occurrence, specifically over the past century. Global warming has caused an 8 inch sea level rise since 1990, which made the coastal flood zone wider, deeper and more damaging. Additionally, riverine flooding is extremely damaging to the country's substructure and economy as well which causes river banks to overflow, inundating low-lying areas. New Jersey and New York are two areas at severe risk for flood hazard, sea level rise, land depletion and economic loss which are the main study area of this work. A decision making framework is being built to help mitigate the impacts of the environmental and economical dangers of storm surges, sea level rise, flashfloods and inland flooding. With vigorous research and the use of innovative hydrologic modeling software, this tool can be built and utilized to form resiliency for coastal communities. This will allow the individuals living in a coastal community to understand the details of climatic hazards in their area and risks associated to their communities. This tool will also suggest the best solution for the problem each community faces. Atlantic City and New York City has been modeled and compared using potential storm events and the outcomes have been analyzed. The tool offers all the possible solutions for the type of flooding that occurs. Green infrastructure such as rain gardens, detention basins and green roofs can be used as small scale solutions. Greater scale solutions such as removable flood barriers, concrete walls and height adjustable walls will also be displayed if that poses as the best solution. The results and benefits from the simulation and modeling techniques, will allow coastal communities to choose the most appropriate method for building a long lasting and sustainable resilience plan in the future.

  16. Effects of a surfacing effluent plume on a coastal phytoplankton community

    KAUST Repository

    Reifel, Kristen M.

    2013-06-01

    Urban runoff and effluent discharge from heavily populated coastal areas can negatively impact water quality, beneficial uses, and coastal ecosystems. The planned release of treated wastewater (i.e. effluent) from the City of Los Angeles Hyperion Wastewater Treatment Plant, located in Playa del Rey, California, provided an opportunity to study the effects of an effluent discharge plume from its initial release until it could no longer be detected in the coastal ocean. Non-metric multi-dimensional scaling analysis of phytoplankton community structure revealed distinct community groups based on salinity, temperature, and CDOM concentration. Three dinoflagellates (Lingulodinium polyedrum, Cochlodinium sp., Akashiwo sanguinea) were dominant (together >50% abundance) prior to the diversion. Cochlodinium sp. became dominant (65-90% abundance) within newly surfaced wastewater, and A. sanguinea became dominant or co-dominant as the effluent plume aged and mixed with ambient coastal water. Localized blooms of Cochlodinium sp. and A. sanguinea (chlorophyll a up to 100mgm-3 and densities between 100 and 2000cellsmL-1) occurred 4-7 days after the diversion within the effluent plume. Although both Cochlodinium sp. and A. sanguinea have been occasionally reported from California waters, blooms of these species have only recently been observed along the California coast. Our work supports the hypothesis that effluent and urban runoff discharge can stimulate certain dinoflagellate blooms. All three dinoflagellates have similar ecophysiological characteristics; however, small differences in morphology, nutrient preferences, and environmental requirements may explain the shift in dinoflagellate composition. © 2013 Elsevier Ltd.

  17. Establishment and formation of fog-dependent Tillandsia landbeckii dunes in the Atacama Desert: Evidence from radiocarbon and stable isotopes

    Science.gov (United States)

    Latorre, Claudio; GonzáLez, AngéLica L.; Quade, Jay; FariñA, José M.; Pinto, Raquel; Marquet, Pablo A.

    2011-09-01

    Extensive dune fields made up exclusively of the bromeliad Tillandsia landbeckii thrive in the Atacama Desert, one of the most extreme landscapes on earth. These plants survive by adapting exclusively to take in abundant advective fog and dew as moisture sources. Although some information has been gathered regarding their modern distribution and adaptations, very little is known about how these dune systems actually form and accumulate over time. We present evidence based on 20 radiocarbon dates for the establishment age and development of five different such dune systems located along a ˜215 km transect in northern Chile. Using stratigraphy, geochronology and stable C and N isotopes, we (1) develop an establishment chronology of these ecosystems, (2) explain how the unique T. landbeckii dunes form, and (3) link changes in foliar δ15N values to moisture availability in buried fossil T. landbeckii layers. We conclude by pointing out the potential that these systems have for reconstructing past climate change along coastal northern Chile during the late Holocene.

  18. Dunes Around Khnifiss Lagoon (Tarfaya, SW of Morocco): Composition, Itinerary In Dune Fields, Effects on Dunes' Colours and Morphodynamic

    Science.gov (United States)

    Adnani, M.; Azzaoui, M. A.; Elbelrhiti, H.; Ahmamou, M.; Masmoudi, L.

    2015-12-01

    Dunes around Khnifiss lagoon (28° 3'N, 12°13'W) show different colors ranging from black at the beach, whitish yellow in transverse dunes near the beach to reddish at the mega barchans situated few kilometers in the SW. The scientific question is about the abundance of different dunes in the same environmental conditions. The present work aims to investigate the factors that influence dunes color change, and then at which degree these factors could control dunes stability. To highlight the difference in color observed at the dune fields then to characterize dunes mineralogy, Landsat TM images were used in addition to mineralogical analysis that was carried out for the black grains samples originated from megabarchans. Optic Microscope and SEM- EDS data was adopted, in addition to physico-chemical analysis provided by Electronic Microprobe. Grain size and shape analysis were conducted to characterize the different types of grains of sand. 3/1 Landsat image band ratio allowed iron oxide distinction, the results revealed the importance of iron oxide concentration. Furthermore, mineralogical and physico-chemical analysis revealed (i) a high grade of oxides (Rutile, Ilmenite, Magnetite, Ulvöspinel) in samples, (ii) silicates (Quartz, Clinopyroxene, feldspar, Zircon), (iii) phosphate (apatite) and (iv) carbonate (calcite). The grain size analysis of the sand originated from the megabarchans reveals that there are three populations of sand. Black grains with a diameter less than 100μm and dominated by the magnetite, red ones composed mainly by the quartz with diameter between 100 and 180 μm and grains with diameter more than 180 μm are white and composed by carbonates. The threshold of motion of these different grains was calculated. It shows that these different grains have the same threshold of motion, which means that the grain size compensates the density. This explains the abundance of different populations of sand in the same environment. The dominance of iron

  19. Function assessment of coastal ecosystem based on phytoplankton community structure

    DEFF Research Database (Denmark)

    Haraguchi, Lumi

    2018-01-01

    on phytoplankton community structure; and 3) investigating the role of planktonic communities on the cycling of dissolved organic matter. Those objectives were addressed focusing the temperate mesohaline estuary of Roskilde Fjord (Denmark). Paper I, explores the use of Pulse-shape recording flow cytometry (PFCM...... as an energy reservoir, buffering changes in the nutrient supply. Finally, the results embedded in this thesis demonstrate the importance of integrating different time scales to understand functioning of phytoplankton communities. Phytoplankton dynamics should not be regarded just in light of inorganic......This Ph.D. project aimed to improve the knowledge on phytoplankton community structure and its influence in the carbon transfer and nutrient cycling in coastal waters, by: 1) assessing the importance of phytoplankton

  20. Natural shorelines promote the stability of fish communities in an urbanized coastal system.

    Directory of Open Access Journals (Sweden)

    Steven B Scyphers

    Full Text Available Habitat loss and fragmentation are leading causes of species extinctions in terrestrial, aquatic and marine systems. Along coastlines, natural habitats support high biodiversity and valuable ecosystem services but are often replaced with engineered structures for coastal protection or erosion control. We coupled high-resolution shoreline condition data with an eleven-year time series of fish community structure to examine how coastal protection structures impact community stability. Our analyses revealed that the most stable fish communities were nearest natural shorelines. Structurally complex engineered shorelines appeared to promote greater stability than simpler alternatives as communities nearest vertical walls, which are among the most prevalent structures, were most dissimilar from natural shorelines and had the lowest stability. We conclude that conserving and restoring natural habitats is essential for promoting ecological stability. However, in scenarios when natural habitats are not viable, engineered landscapes designed to mimic the complexity of natural habitats may provide similar ecological functions.

  1. Spatio-temporal distribution patterns of the epibenthic community in the coastal waters of Suriname

    Science.gov (United States)

    Willems, Tomas; De Backer, Annelies; Wan Tong You, Kenneth; Vincx, Magda; Hostens, Kris

    2015-10-01

    This study aimed to characterize the spatio-temporal patterns of the epibenthic community in the coastal waters of Suriname. Data were collected on a (bi)monthly basis in 2012-2013 at 15 locations in the shallow (turbid-water zone (6-20 m depth), dominated by Atlantic seabob shrimp Xiphopenaeus kroyeri (Crustacea: Penaeoidea). Near the 30 m isobath, sediments were much coarser (median grain size on average 345±103 μm vs. 128±53 μm in the coastal assemblage) and water transparency was much higher (on average 7.6±3.5 m vs. 2.4±2.1 m in the coastal assemblage). In this zone, a diverse offshore assemblage was found, characterized by brittle stars (mainly Ophioderma brevispina and Ophiolepis elegans) and a variety of crabs, sea stars and hermit crabs. In between both zones, a transition assemblage was noted, with epibenthic species typically found in either the coastal or offshore assemblages, but mainly characterized by the absence of X. kroyeri. Although the epibenthic community was primarily structured in an on-offshore gradient related to depth, sediment grain size and sediment total organic carbon content, a longitudinal (west-east) gradient was apparent as well. The zones in the eastern part of the Suriname coastal shelf seemed to be more widely stretched along the on-offshore gradient. Although clear seasonal differences were noted in the environmental characteristics (e.g. dry vs. rainy season), this was not reflected in the epibenthic community structure. X. kroyeri reached very high densities (up to 1383 ind 1000 m-²) in the shallow coastal waters of Suriname. As X. kroyeri is increasingly exploited throughout its range, the current study provides the ecological context for its presence and abundance, which is crucial for an ecosystem approach and the sustainable management of this commercially important species and its habitat.

  2. Mapping invasive woody species in coastal dunes in the Netherlands: a remote sensing approach using LIDAR and high-resolution aerial photographs

    NARCIS (Netherlands)

    Hantson, W.P.R.; Kooistra, L.; Slim, P.A.

    2012-01-01

    Questions Does remote sensing improve classification of invasive woody species in dunes, useful for shrub management? Does additional height information and an object-based classifier increase woody species classification accuracy? Location The dunes of Vlieland, one of the Wadden Sea Islands, the

  3. Predictive occurrence models for coastal wetland plant communities: Delineating hydrologic response surfaces with multinomial logistic regression

    Science.gov (United States)

    Snedden, Gregg A.; Steyer, Gregory D.

    2013-02-01

    Understanding plant community zonation along estuarine stress gradients is critical for effective conservation and restoration of coastal wetland ecosystems. We related the presence of plant community types to estuarine hydrology at 173 sites across coastal Louisiana. Percent relative cover by species was assessed at each site near the end of the growing season in 2008, and hourly water level and salinity were recorded at each site Oct 2007-Sep 2008. Nine plant community types were delineated with k-means clustering, and indicator species were identified for each of the community types with indicator species analysis. An inverse relation between salinity and species diversity was observed. Canonical correspondence analysis (CCA) effectively segregated the sites across ordination space by community type, and indicated that salinity and tidal amplitude were both important drivers of vegetation composition. Multinomial logistic regression (MLR) and Akaike's Information Criterion (AIC) were used to predict the probability of occurrence of the nine vegetation communities as a function of salinity and tidal amplitude, and probability surfaces obtained from the MLR model corroborated the CCA results. The weighted kappa statistic, calculated from the confusion matrix of predicted versus actual community types, was 0.7 and indicated good agreement between observed community types and model predictions. Our results suggest that models based on a few key hydrologic variables can be valuable tools for predicting vegetation community development when restoring and managing coastal wetlands.

  4. The Coastal Resilience Index: High School Students Planning for Their Community's Future

    Science.gov (United States)

    Kastler, J. A.; Dorcik, S.; Sempier, T.; Kimbrell, C.

    2017-12-01

    Communities in Jackson County, Mississippi sustained heavy damages during Hurricane Katrina in 2005 and are expected to experience early effects as sea level rise and increasing episodes of nuisance flooding. Many high school students still remember months-long evacuations and other disruptions to home and family in 2005. Others do not remember or moved here recently. None anticipate their communities are likely to face similar challenges in the future, nor do they have a strong understanding that preparing for such an event is a practical, local career choice for a science major. Through a series of classroom and field lessons, students in two coastal communities learned how and why coastal habitats are changing, and how modeling predicts future impacts. During a culminating experience students learn how to use the Coastal Resilience Index developed by Mississippi Alabama Sea Grant Consortium. Working in teams or three to four students, the students addressed one of twelve scenarios based on real experiences observed by Gulf Coast communities during their post-hurricane assessments. Each team explored its topic using internet resources and conversations with family members, then worked together to brainstorm possible approaches to address the situation described in their scenario. They selected one potential solution for their focus and developed it, ultimately producing a poster of the scenario and their idea of its solution. The teams gathered at the University of Southern Mississippi at the end of the term to present their work, science fair style, to a selection of community leaders from the Climate Community of Practice. Posters were judged and best poster presentations were awarded. This talk will focus on the evaluation results. Existing qualitative observations show differences in awareness and self-efficacy to work productively in this field. Community leaders expressed interest in the solutions offered. Ongoing quantitative evaluations will also be

  5. Dune growth under multidirectional wind regimes

    Science.gov (United States)

    Gadal, C.; Rozier, O.; Claudin, P.; Courrech Du Pont, S.; Narteau, C.

    2017-12-01

    Under unidirectional wind regimes, flat sand beds become unstable to produce periodic linear dunes, commonly called transverse dunes because their main ridges are oriented perpendicular to the air flow. In areas of low sediment availability, the same interactions between flow, transport and topography produce barchan dunes, isolated sand-pile migrating over long distances with a characteristic crescentic shape. For the last fifteen years, barchan dunes and the instability at the origin of transverse dunes have been the subject of numerous studies that have identified a set of characteristic length and time scales with respect to the physical properties of both grains and fluid. This is not the case for dunes developing under multidirectional wind regimes. Under these conditions, dune orientation is measured with respect to the direction of the resultant sand flux. Depending on the wind regime, dunes do not always line up perpendicularly to the resultant sand flux, but can also be at an oblique angle or even parallel to it. These oblique and longitudinal dunes are ubiquitous in all deserts on Earth and planetary bodies because of the seasonal variability of wind orientation. They are however poorly constrained by observations and there is still no complete theoretical framework providing a description of their orientation and initial wavelength. Here, we extend the linear stability analysis of a flat sand of bed done in two dimensions for a unidirectional flow to three dimensions and multidirectional flow regimes. We are able to recover transitions from transverse to oblique or longitudinal dune patterns according to changes in wind regimes. We besides give a prediction for the initial dune wavelength. Our results compare well to previous theory of dune orientation and to field, experimental and numerical data.

  6. Global learning for local solutions: Reducing vulnerability of marine-dependent coastal communities

    Science.gov (United States)

    Salim, S. S.; Paytan, A.

    2016-12-01

    The project `Global learning for local solutions: Reducing vulnerability of marine-dependent coastal communities' (GULLS) falls within the Belmont Forum and G8 Research Councils Initiative on Multilateral Research Funding. Participants include teams from nine countries: Australia, Brazil, India, Madagascar, Mozambique, New Zealand, South Africa, the United Kingdom and the United States of America. The project focuses on five regional `hotspots' of climate and social change, defined as fast-warming marine areas and areas experiencing social tensions as a result of change: south-east Australia, Brazil, India, South Africa, and the Mozambique Channel and adjacent countries of Mozambique and Madagascar. These areas require most urgent attention and serve as valuable case studies for wider applications. The project aims to assist coastal communities and other stakeholders dependent on marine resources to adapt to climate change and variability through an integrated and trans-disciplinary approach. Combining best available global knowledge with local knowledge and conditions, it is exploring adaptation options and approaches to strengthen resilience at local and community levels, with a focus on options for reconciling the needs for food security with long-term sustainability and conservation. The project will also contribute to capacity development and empowering fishing communities and other fisheries-dependent stakeholders.A standardized vulnerability assessment framework is being developed that will be used to integrate results from natural, social and economic studies in order to identify needs and options for strengthening management and existing policies. Structured comparisons between the hot-spots will assist global efforts for adaptation and strengthening resilience in marine and coastal social-ecological systems.

  7. Size distribution and structure of Barchan dune fields

    Directory of Open Access Journals (Sweden)

    O. Durán

    2011-07-01

    Full Text Available Barchans are isolated mobile dunes often organized in large dune fields. Dune fields seem to present a characteristic dune size and spacing, which suggests a cooperative behavior based on dune interaction. In Duran et al. (2009, we propose that the redistribution of sand by collisions between dunes is a key element for the stability and size selection of barchan dune fields. This approach was based on a mean-field model ignoring the spatial distribution of dune fields. Here, we present a simplified dune field model that includes the spatial evolution of individual dunes as well as their interaction through sand exchange and binary collisions. As a result, the dune field evolves towards a steady state that depends on the boundary conditions. Comparing our results with measurements of Moroccan dune fields, we find that the simulated fields have the same dune size distribution as in real fields but fail to reproduce their homogeneity along the wind direction.

  8. Study of Goa and its environment from space: A report on coastal sand dune ecosystems of Goa: Siginficance, uses and anthropogenic impacts

    Digital Repository Service at National Institute of Oceanography (India)

    Mascarenhas, A.

    by regular tides which raise or lower water levels by 2 or 3 meters daily. It is these geomorphic features which support mangrove thickets which are today visible far into the hinterland along river banks, distributary channels, creeks and lagoons. Several... the maximum brunt of this "development". The beach - dune environment is a highly organized system. Sand dunes which generally back wide beaches, are features of extreme fragility and sensitive to anthropogenic stress. Sand dunes are Nature's line of defense...

  9. Responses of woody species to spatial and temporal ground water changes in coastal sand dune systems

    Science.gov (United States)

    Máguas, C.; Rascher, K. G.; Martins-Loução, A.; Carvalho, P.; Pinho, P.; Ramos, M.; Correia, O.; Werner, C.

    2011-12-01

    In spite of the relative importance of groundwater in costal dune systems, studies concerning the responses of vegetation to ground water (GW) availability variations, particularly in Mediterranean regions, are scarce. Thus, the main purpose of this study is to compare the responses of co-occurring species possessing different functional traits, to changes in GW levels (i.e. the lowering of GW levels) in a sand dune ecosystem. For that, five sites were established within a 1 km2 area in a meso-mediterranean sand dune ecosystem dominated by a Pinus pinaster forest. Due to natural topographic variability and anthropogenic GW exploitation, substantial variability in depth to GW between sites was found. Under these conditions it was possible to identify the degree of usage and dependence on GW of different plant species (two deep-rooted trees, a drought adapted shrub, a phreatophyte and a non-native woody invader) and how GW dependence varied seasonally and between the heterogeneous sites. Results indicated that the plant species had differential responses to changes in GW depth according to specific functional traits (i.e. rooting depth, leaf morphology, and water use strategy). Species comparison revealed that variability in pre-dawn water potential (Ψpre) and bulk leaf δ13C was related to site differences in GW use in the deep-rooted (Pinus pinaster, Myrica faya) and phreatophyte (Salix repens) species. However, such variation was more evident during spring than during summer drought. The exotic invader, Acacia longifolia, which does not possess a very deep root system, presented the largest seasonal variability in Ψpre and bulk leaf δ13C. In contrast, the response of Corema album, an endemic understory drought-adapted shrub, seemed to be independent of water availability across seasons and sites. Thus, the susceptibility to lowering of GW due to anthropogenic exploitation, in plant species from sand dunes, is variable, being particularly relevant for deep

  10. Comparison of the active and resident community of a coastal microbial mat

    OpenAIRE

    Cardoso, Daniela Clara; Sandionigi, Anna; Cretoiu, Mariana Silvia; Casiraghi, Maurizio; Stal, Lucas; Bolhuis, Henk

    2017-01-01

    Coastal microbial mats form a nearly closed micro-scale ecosystem harboring a complex microbial community. Previous DNA based analysis did not necessarily provide information about the active fraction of the microbial community because it includes dormant, inactive cells as well as a potential stable pool of extracellular DNA. Here we focused on the active microbial community by comparing 16S rRNA sequences obtained from the ribosomal RNA pool with gene sequences obtained from the DNA fractio...

  11. Coastal Innovation Imperative

    Directory of Open Access Journals (Sweden)

    Bruce C. Glavovic

    2013-03-01

    Full Text Available This is the second of two articles that explores the coastal innovation paradox and imperative. Paradoxically, innovation is necessary to escape the vulnerability trap created by past innovations that have degraded coastal ecosystems and imperil coastal livelihoods. The innovation imperative is to reframe and underpin business and technology with coherent governance innovations that lead to social transformation for coastal sustainability. How might coastal management help to facilitate this transition? It is argued that coastal management needs to be reconceptualised as a transformative practice of deliberative coastal governance. A foundation comprising four deliberative or process outcomes is posited. The point of departure is to build human and social capital through issue learning and improved democratic attitudes and skills. Attention then shifts to facilitating community-oriented action and improving institutional capacity and decision-making. Together, these endeavours enable improved community problem-solving. The ultimate process goal is to build more collaborative communities. Instituting transformative deliberative coastal governance will help to stimulate innovations that chart new sustainability pathways and help to resolve the coastal problems. This framework could be adapted and applied in other geographical settings.

  12. Using Bi-Seasonal WorldView-2 Multi-Spectral Data and Supervised Random Forest Classification to Map Coastal Plant Communities in Everglades National Park

    Directory of Open Access Journals (Sweden)

    Kristie S. Wendelberger

    2018-03-01

    Full Text Available Coastal plant communities are being transformed or lost because of sea level rise (SLR and land-use change. In conjunction with SLR, the Florida Everglades ecosystem has undergone large-scale drainage and restoration, altering coastal vegetation throughout south Florida. To understand how coastal plant communities are changing over time, accurate mapping techniques are needed that can define plant communities at a fine-enough resolution to detect fine-scale changes. We explored using bi-seasonal versus single-season WorldView-2 satellite data to map three mangrove and four adjacent plant communities, including the buttonwood/glycophyte community that harbors the federally-endangered plant Chromolaena frustrata. Bi-seasonal data were more effective than single-season to differentiate all communities of interest. Bi-seasonal data combined with Light Detection and Ranging (LiDAR elevation data were used to map coastal plant communities of a coastal stretch within Everglades National Park (ENP. Overall map accuracy was 86%. Black and red mangroves were the dominant communities and covered 50% of the study site. All the remaining communities had ≤10% cover, including the buttonwood/glycophyte community. ENP harbors 21 rare coastal species threatened by SLR. The spatially explicit, quantitative data provided by our map provides a fine-scale baseline for monitoring future change in these species’ habitats. Our results also offer a method to monitor vegetation change in other threatened habitats.

  13. Using Bi-Seasonal WorldView-2 Multi-Spectral Data and Supervised Random Forest Classification to Map Coastal Plant Communities in Everglades National Park.

    Science.gov (United States)

    Wendelberger, Kristie S; Gann, Daniel; Richards, Jennifer H

    2018-03-09

    Coastal plant communities are being transformed or lost because of sea level rise (SLR) and land-use change. In conjunction with SLR, the Florida Everglades ecosystem has undergone large-scale drainage and restoration, altering coastal vegetation throughout south Florida. To understand how coastal plant communities are changing over time, accurate mapping techniques are needed that can define plant communities at a fine-enough resolution to detect fine-scale changes. We explored using bi-seasonal versus single-season WorldView-2 satellite data to map three mangrove and four adjacent plant communities, including the buttonwood/glycophyte community that harbors the federally-endangered plant Chromolaena frustrata . Bi-seasonal data were more effective than single-season to differentiate all communities of interest. Bi-seasonal data combined with Light Detection and Ranging (LiDAR) elevation data were used to map coastal plant communities of a coastal stretch within Everglades National Park (ENP). Overall map accuracy was 86%. Black and red mangroves were the dominant communities and covered 50% of the study site. All the remaining communities had ≤10% cover, including the buttonwood/glycophyte community. ENP harbors 21 rare coastal species threatened by SLR. The spatially explicit, quantitative data provided by our map provides a fine-scale baseline for monitoring future change in these species' habitats. Our results also offer a method to monitor vegetation change in other threatened habitats.

  14. A field test of the centrifugal community organization model using psammophilic gerbils in Israel's southern coastal plain

    Science.gov (United States)

    Wasserberg, Gideon; Kotler, B.P.; Morris, D.W.; Abramsky, Z.

    2007-01-01

    Background: An optimal habitat selection model called centrifugal community organization (CCO) predicts that species, although they have the same primary habitat, may co-exist owing to their ability to use different secondary habitats. Goal: Test the predictions of CCO with field experiments. Species: The Egyptian sand gerbil (40 g), Gerbillus pyramidum, and Allenby's gerbil (25 g), G. andersoni allenbyi. Site: Ashdod sand dunes in the southern coastal plain of Israel. Three sandy habitats are present: shifting, semi-stabilized, and stabilized sand. Gerbils occupied all three habitats. Methods: We surveyed rodent abundance, activity levels, and foraging behaviour while experimentally removing G. pyramidum. Results: Three predictions of the CCO model were supported. Both species did best in the semi-stabilized habitat. However, they differed in their secondary habitats. Gerbillus pyramidum preferred the shifting sand habitat, whereas G. a. allenbyi preferred the stabilized habitat. Habitat selection by both species depended on density. However, in contrast to CCO, G. pyramidum dominated the core habitat and excluded G. a. allenbyi. We term this variant of CCO, 'asymmetric CCO'. Conclusions: The fundamental feature of CCO appears valid: co-existence may result not because of what each competing species does best, but because of what they do as a back-up. But in contrast to the prediction of the original CCO model, all dynamic traces of interaction can vanish if the system includes interference competition. ?? 2007 Gideon Wasserberg.

  15. Why is Coastal Community Resilience Important in the Gulf of Mexico Region?

    Science.gov (United States)

    The Gulf of Mexico Program supports the regional collaborative approach and efforts of the Coastal Community Resilience Priority Issue Team of the Gulf of Mexico Governors’ Alliance and its broad spectrum of partners and stakeholders.

  16. Dunes with Frost

    Science.gov (United States)

    2004-01-01

    31 May 2004 Springtime for the martian northern hemisphere brings defrosting spots and patterns to the north polar dune fields. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example located near 76.7oN, 250.4oW. In summer, these dunes would be darker than their surroundings. However, while they are still covered by frost, they are not any darker than the substrate across which the sand is slowly traveling. Dune movement in this case is dominated by winds that blow from the southwest (lower left) toward the northeast (upper right). The picure covers an area about 3 km (1.9 mi) across and is illuminated by sunlight from the lower left.

  17. Mars Global Digital Dune Database; MC-1

    Science.gov (United States)

    Hayward, R.K.; Fenton, L.K.; Tanaka, K.L.; Titus, T.N.; Colaprete, A.; Christensen, P.R.

    2010-01-01

    The Mars Global Digital Dune Database presents data and describes the methodology used in creating the global database of moderate- to large-size dune fields on Mars. The database is being released in a series of U.S. Geological Survey (USGS) Open-File Reports. The first release (Hayward and others, 2007) included dune fields from 65 degrees N to 65 degrees S (http://pubs.usgs.gov/of/2007/1158/). The current release encompasses ~ 845,000 km2 of mapped dune fields from 65 degrees N to 90 degrees N latitude. Dune fields between 65 degrees S and 90 degrees S will be released in a future USGS Open-File Report. Although we have attempted to include all dune fields, some have likely been excluded for two reasons: (1) incomplete THEMIS IR (daytime) coverage may have caused us to exclude some moderate- to large-size dune fields or (2) resolution of THEMIS IR coverage (100m/pixel) certainly caused us to exclude smaller dune fields. The smallest dune fields in the database are ~ 1 km2 in area. While the moderate to large dune fields are likely to constitute the largest compilation of sediment on the planet, smaller stores of sediment of dunes are likely to be found elsewhere via higher resolution data. Thus, it should be noted that our database excludes all small dune fields and some moderate to large dune fields as well. Therefore, the absence of mapped dune fields does not mean that such dune fields do not exist and is not intended to imply a lack of saltating sand in other areas. Where availability and quality of THEMIS visible (VIS), Mars Orbiter Camera narrow angle (MOC NA), or Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) images allowed, we classified dunes and included some dune slipface measurements, which were derived from gross dune morphology and represent the prevailing wind direction at the last time of significant dune modification. It was beyond the scope of this report to look at the detail needed to discern subtle dune modification. It was also

  18. Frost on Dunes

    Science.gov (United States)

    2005-01-01

    18 March 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark dunes on a crater floor during the southern spring. Some of the dunes have frost on their south-facing slopes. Location near: 52.3oS, 326.7oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  19. Predictive occurrence models for coastal wetland plant communities: delineating hydrologic response surfaces with multinomial logistic regression

    Science.gov (United States)

    Snedden, Gregg A.; Steyer, Gregory D.

    2013-01-01

    Understanding plant community zonation along estuarine stress gradients is critical for effective conservation and restoration of coastal wetland ecosystems. We related the presence of plant community types to estuarine hydrology at 173 sites across coastal Louisiana. Percent relative cover by species was assessed at each site near the end of the growing season in 2008, and hourly water level and salinity were recorded at each site Oct 2007–Sep 2008. Nine plant community types were delineated with k-means clustering, and indicator species were identified for each of the community types with indicator species analysis. An inverse relation between salinity and species diversity was observed. Canonical correspondence analysis (CCA) effectively segregated the sites across ordination space by community type, and indicated that salinity and tidal amplitude were both important drivers of vegetation composition. Multinomial logistic regression (MLR) and Akaike's Information Criterion (AIC) were used to predict the probability of occurrence of the nine vegetation communities as a function of salinity and tidal amplitude, and probability surfaces obtained from the MLR model corroborated the CCA results. The weighted kappa statistic, calculated from the confusion matrix of predicted versus actual community types, was 0.7 and indicated good agreement between observed community types and model predictions. Our results suggest that models based on a few key hydrologic variables can be valuable tools for predicting vegetation community development when restoring and managing coastal wetlands.

  20. Composition And Geometry Of Titan'S Dunes

    Science.gov (United States)

    Le Gall, Alice; Janssen, M. A.; Wye, L. C.; Lorenz, R. D.; Radebaugh, J.; Cassini RADAR Team

    2009-09-01

    Fields of linear dunes cover a large portion of Titan's equatorial regions. As the Cassini mission continues, more of them are unveiled and examined by the microwave Titan RADAR Mapper both in the active and passive modes of operation of the instrument and with an increasing variety of observational geometries. In this presentation, we will show that the joint analysis of the SAR (Synthetic Aperture Radar) and radiometry observations of the dunes at closest approach supports the idea of different composition between the dunes and the interdunes. It suggests that the icy bedrock of Titan may be exposed, or partially exposed, in the interdunes. We also see regional differences among dune fields. Dunes are highly directional features; their visibility is controlled by the look direction and the incidence angle. We have developed a backscatter and emissivity model that takes into account the topography of the dunes relative to the geometry of observation as well as the composition of the dunes and interdunes. Compared to observations and, in particular, to multiple observations of areas at the overlap of several swaths, we argue the need for a diffuse scattering mechanism. The presence of ripples in the dunes and/or interdunes might account for the recorded backscatter. In this presentation we will also report the results of the T61 experiment. The T61 HiSAR sequence (on August 25, 2009) was designed to examine a small region of the Shangri-La dune field with a substantial sampling of incidence angles around the direction perpendicular to the dunes long axis. The spot in question was already observed during the T55 SAR swath and the T61 experiment should allow us to determine the slope of the dunes.

  1. Dune mobility in the St. Anthony Dune Field, Idaho, USA: Effects of meteorological variables and lag time

    Science.gov (United States)

    Hoover, R. H.; Gaylord, D. R.; Cooper, C. M.

    2018-05-01

    The St. Anthony Dune Field (SADF) is a 300 km2 expanse of active to stabilized transverse, barchan, barchanoid, and parabolic sand dunes located in a semi-arid climate in southeastern Idaho. The northeastern portion of the SADF, 16 km2, was investigated to examine meteorological influences on dune mobility. Understanding meteorological predictors of sand-dune migration for the SADF informs landscape evolution and impacts assessment of eolian activity on sensitive agricultural lands in the western United States, with implications for semi-arid environments globally. Archival aerial photos from 1954 to 2011 were used to calculate dune migration rates which were subsequently compared to regional meteorological data, including temperature, precipitation and wind speed. Observational analyses based on aerial photo imagery and meteorological data indicate that dune migration is influenced by weather for up to 5-10 years and therefore decadal weather patterns should be taken into account when using dune migration rates as proxies from climate fluctuation. Statistical examination of meteorological variables in this study indicates that 24% of the variation of sand dune migration rates is attributed to temperature, precipitation and wind speed, which is increased to 45% when incorporating lag time.

  2. Strategy of Developing Tomini Bay for Economic Growth of Coastal Community in Central Sulawesi

    Directory of Open Access Journals (Sweden)

    Muzakir Muzakir

    2016-06-01

    Full Text Available This research aims to analyze the potential and the strategy of developing Tomini Bay to improve the economic growth of the coastal community in Central Sulawesi. The research is located in four regencies in Central Sulawesi. The method uses the descriptive analysis using SWOT analysis. The research result shows that the potential of fisheries resources in Poso Regency, Parigi Moutong Regency, Tojo Una-Una Regency, and Banggai Regency can support the development of Tomini Bay region based on fisheries in order to accelerate the economic growth of coastal communities in Central Sulawesi. The potential fishery resources that can support the development of Tomini Bay area are the potential of fisheries, marine and coastal infrastructure, social economy and geographic conditions in four regencies. The strategies are building the marketing network for fishery products both the catching and cultivation, improving the fishery human resouce capacity, controlling the fishery product quality, and increasing the social awareness to maintain the ecosystem sustainability. To optimize the utilization of Tomini Bay, it is suggested to improve the involvement of the regional government, the central government, and also the private sector and the whole community.

  3. Sand dune movement in the Victoria Valley, Antarctica

    Science.gov (United States)

    Bourke, Mary C.; Ewing, Ryan C.; Finnegan, David; McGowan, Hamish A.

    2009-08-01

    We use vertical aerial photographs and LiDAR topographic survey data to estimate dune migration rates in the Victoria Valley dunefield, Antarctica, between 1961 and 2001. Results confirm that the dunes migrated an average of 1.5 m/year. These values are consistent with other estimates of dune migration from cold climate deserts and are significantly lower than estimates from warm deserts. Dune migration rates are retarded by the presence of entrained ice, soil moisture and a reversing wind regime. Dune absorption, merging and limb extension are apparent from the time-series images and account for significant changes in dune form and the field-scale dune pattern. Dune-field pattern analysis shows an overall increase in dune-field organization with an increase in mean dune spacing and a reduction in total crest length and defect density. These data suggest that dunes in other cold desert environments on Earth, Mars or Titan, that may also have inter-bedded frozen laminae, still have the potential to migrate and organize, albeit at lower rates than dunes in warm deserts.

  4. Coastal erosion triggered by a shipwreck along the coast of Goa, India

    Digital Repository Service at National Institute of Oceanography (India)

    ManiMurali, R.; Babu, M.T.; Mascarenhas, A.; Choudhary, R.; Sudheesh, K.; Vethamony, P.

    dunes and, as a consequence, has gradually become fragile due to severe erosion. Keywords: Coastal erosion, cyclone, remote sensing images, shipwreck. GOA is one of the most famous tourist coasts of the world. In general, the sea front of Goa... times due to the sudden boom of real estate sector, mushrooming of industries, inconsistent tourist flows, with a consequent impact on coastal ecosystems. Changes in the land-use/land-cover, geomorphology, ecology and sensitivity of coasts were...

  5. Environmental Controls and Eco-geomorphic Interactions of the Barchan-to-parabolic Dune Stabilisation and the Parabolic-to-barchan Dune Reactivation

    Science.gov (United States)

    Yan, Na; Baas, Andreas

    2015-04-01

    Parabolic dunes are one of a few common aeolian landforms which are highly controlled by eco-geomorphic interactions. Parabolic dunes, on the one hand, can be developed from highly mobile dune landforms, barchans for instance, in an ameliorated vegetation condition; or on the other hand, they can be reactivated and transformed back into mobile dunes due to vegetation deterioration. The fundamental mechanisms and eco-geomorphic interactions controlling both dune transformations remain poorly understood. To bridge the gap between complex processes involved in dune transformations on a relatively long temporal scale and real world monitoring records on a very limited temporal scale, this research has extended the DECAL model to incorporate 'dynamic' growth functions and the different 'growth' of perennial shrubs between growing and non-growing seasons, informed by field measurements and remote sensing analysis, to explore environmental controls and eco-geomorphic interactions of both types of dune transformation. A non-dimensional 'dune stabilising index' is proposed to capture the interactions between environmental controls (i.e. the capabilities of vegetation to withstand wind erosion and sand burial, the sandy substratum thickness, the height of the initial dune, and the sand transport potential), and establish the linkage between these controls and the geometry of a stabilising dune. An example demonstrates how to use the power-law relationship between the dune stabilising index and the normalised migration distance to assist in extrapolating the historical trajectories of transforming dunes. The modelling results also show that a slight increase in vegetation cover of an initial parabolic dune can significantly increase the reactivation threshold of climatic impact (both drought stress and wind strength) required to reactivate a stabilising parabolic dune into a barchan. Four eco-geomorphic interaction zones that govern a barchan-to-parabolic dune transformation

  6. Short-term meso-scale variability of mesozooplankton communities in a coastal upwelling system (NW Spain)

    Science.gov (United States)

    Roura, Álvaro; Álvarez-Salgado, Xosé A.; González, Ángel F.; Gregori, María; Rosón, Gabriel; Guerra, Ángel

    2013-02-01

    The short-term, meso-scale variability of the mesozooplankton community present in the coastal upwelling system of the Ría de Vigo (NW Spain) has been analysed. Three well-defined communities were identified: coastal, frontal and oceanic, according to their holoplankton-meroplankton ratio, richness, and total abundance. These communities changed from summer to autumn due to a shift from downwelling to upwelling-favourable conditions coupled with taxa dependent changes in life strategies. Relationships between the resemblance matrix of mesozooplankton and the resemblance matrices of meteorologic, hydrographic and community-derived biotic variables were determined with distance-based linear models (DistLM, 18 variables), showing an increasing amount of explained variability of 6%, 16.1% and 54.5%, respectively. A simplified model revealed that the variability found in the resemblance matrix of mesozooplankton was mainly described by the holoplankton-meroplankton ratio, the total abundance, the influence of lunar cycles, the upwelling index and the richness; altogether accounting for 64% of the total variability. The largest variability of the mesozooplankton resemblance matrix (39.6%) is accounted by the holoplankton-meroplankton ratio, a simple index that describes appropriately the coastal-ocean gradient. The communities described herein kept their integrity in the studied upwelling and downwelling episodes in spite of the highly advective environment off the Ría de Vigo, presumably due to behavioural changes in the vertical position of the zooplankton.

  7. Coastal flooding hazard related to storms and coastal evolution in Valdelagrana spit (Cadiz Bay Natural Park, SW Spain)

    Science.gov (United States)

    Benavente, J.; Del Río, L.; Gracia, F. J.; Martínez-del-Pozo, J. A.

    2006-06-01

    Mapping of coastal inundation hazard related to storms requires the combination of multiple sources of information regarding meteorological, morphological and dynamic characteristics of both the area at risk and the studied phenomena. Variables such as beach slope, storm wave height or wind speed have traditionally been used, but detailed geomorphological features of the area as well as long-term shoreline evolution trends must also be taken into account in order to achieve more realistic results. This work presents an evaluation of storm flooding hazard in Valdelagrana spit and marshes (SW Spain), considering two types of storm that are characteristic of the area: a modal storm with 1 year of recurrence interval (maximum wave height of 3.3 m), and an extreme storm with 6-10 years of recurrence interval (maximum wave height of 10.6 m), both approaching the coast perpendicularly. After calculating theoretical storm surge elevation, a digital terrain model was made by adjusting topographic data to field work and detailed geomorphological analysis. A model of flooding extent was subsequently developed for each storm type, and then corrected according to the rates of shoreline change in the last decades, which were assessed by means of aerial photographs taking the dune toe as shoreline indicator. Results show that long-term coastline trend represents an important factor in the prediction of flooding extent, since shoreline retreat causes the deterioration of natural coastal defences as dune ridges, thus increasing coastal exposure to high-energy waves. This way, it has been stated that the lack of sedimentary supply plays an important role in spatial variability of inundation extent in Valdelagrana spit. Finally, a hazard map is presented, where calculated coastal retreat rates are employed in order to predict the areas that could be affected by future inundation events.

  8. Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Atlantic and Gulf Coastal Plain Region (Version 2.0)

    Science.gov (United States)

    2010-11-01

    35 Figure 4. At the toe of a hill slope, the gradient is only slightly inclined or nearly level. ..................... 35...marshes, beach/ dune systems, and wet flats are typical of the outer coastal plain on recent or Holocene sediments, while mixed evergreen/hardwood...mangrove shrublands are also found along the Texas and Louisiana coasts (NatureServe 2006). Beach/ dune systems are typically associated with barrier

  9. Valuing the risk reduction of coastal ecosystems in data poor environments: an application in Quintana Roo, Mexico

    Science.gov (United States)

    Reguero, B. G.; Toimil, A.; Escudero, M.; Menendez, P.; Losada, I. J.; Beck, M. W.; Secaira, F.

    2016-12-01

    Coastal risks are increasing from both economic growth and climate change. Understanding such risks is critical to assessing adaptation needs and finding cost effective solutions for coastal sustainability. Interest is growing in the role that nature-based measures can play in adapting to climate change. Here we apply and advance a framework to value the risk reduction potential of coastal ecosystems, with an application in a large scale domain, the coast of Quintana Roo, México, relevant for coastal policy and management, but with limited data. We build from simple to use open-source tools. We first assess the hazards using stochastic simulation of historical tropical storms and inferring two scenarios of future climate change for the next 20 years, which include the effect of sea level rise and changes in frequency and intensity of storms. For each storm, we obtain wave and surge fields using parametrical models, corrected with pre-computed static wind surge numerical simulations. We then assess losses on capital stock and hotels and calculate total people flooded, after accounting for the effect of coastal ecosystems in reducing coastal hazards. We inferred the location of major barrier reefs and dune systems using available satellite imagery, and sections of bathymetry and elevation data. We also digitalized the surface of beaches and location of coastal structures from satellite imagery. In a poor data environment, where there is not bathymetry data for the whole of the region, we inferred representative coastal profiles of coral reef and dune sections and validated at available sections with measured data. Because we account for the effect of reefs, dunes and mangroves in coastal profiles every 200 m of shoreline, we are able to estimate the value of such ecosystems by comparing with benchmark simulations when we take them out of the propagation and flood model. Although limited in accuracy in comparison to more complex modeling, this approach is able to

  10. Community structure of spiders in coastal habitats of a Mediterranean delta region (Nestos Delta, NE Greece

    Directory of Open Access Journals (Sweden)

    S. Buchholz

    2009-01-01

    Full Text Available (pp 101-115Habitat zonation and ecology of spider assemblages have been poorly studied in Mediterranean ecosystems. A first analysis of spider assemblages in coastal habitats in the east Mediterranean area is presented. The study area is the 250 km² Nestos Delta, located in East Macedonia in the North-East of Greece. Spiders were caught in pitfall traps at 17 sites from the beginning of April to the end of June 2004. Nonparametric estimators were used to determine species richness and alpha diversity. Ordination analysis (redundancy analysis indicated four clearly separable spider species groups (salt meadows, dunes, mea-dows and floodplain forests, along a soil salinity and moisture gradient. Based on these results we discuss the habitat preferences of these spiders and include the first ecological data on several species.

  11. Optical Dating of Holocene Dune Sands in the Ferris Dune Field, Wyoming

    Science.gov (United States)

    Stokes, Stephen; Gaylord, David R.

    1993-05-01

    Optical dating of late Quaternary quartz dune sands from the Clear Creek portion of Ferris dune field, Wyoming, demonstrates the considerable potential of the technique as a chronostratigraphic tool. A sequence of radiocarbon-dated Holocene interdune strata permit optical dating of the intercalated dune sand to be tested; the concordance is good. The optical dates for the aeolian deposits not datable by radiocarbon suggest that aeolian sedimentation at Clear Creek peaked during two relatively short phases at ca. 8500 and 4000 yr B.P. The dates indicate that aeolian accumulation maxima (at least in the Clear Creek area) may not be synchronous with previously defined phases of marked aridity.

  12. Responses of woody species to spatial and temporal ground water changes in coastal sand dune systems

    Directory of Open Access Journals (Sweden)

    C. Máguas

    2011-12-01

    Full Text Available In spite of the relative importance of groundwater in costal dune systems, studies concerning the responses of vegetation to ground water (GW availability variations, particularly in Mediterranean regions, are scarce. Thus, the main purpose of this study is to compare the responses of co-occurring species possessing different functional traits, to changes in GW levels (i.e. the lowering of GW levels in a sand dune ecosystem. For that, five sites were established within a 1 km2 area in a meso-mediterranean sand dune ecosystem dominated by a Pinus pinaster forest. Due to natural topographic variability and anthropogenic GW exploitation, substantial variability in depth to GW between sites was found. Under these conditions it was possible to identify the degree of usage and dependence on GW of different plant species (two deep-rooted trees, a drought adapted shrub, a phreatophyte and a non-native woody invader and how GW dependence varied seasonally and between the heterogeneous sites. Results indicated that the plant species had differential responses to changes in GW depth according to specific functional traits (i.e. rooting depth, leaf morphology, and water use strategy. Species comparison revealed that variability in pre-dawn water potential (Ψpre and bulk leaf δ13C was related to site differences in GW use in the deep-rooted (Pinus pinaster, Myrica faya and phreatophyte (Salix repens species. However, such variation was more evident during spring than during summer drought. The exotic invader, Acacia longifolia, which does not possess a very deep root system, presented the largest seasonal variability in Ψpre and bulk leaf δ13C. In contrast, the response of Corema album, an endemic understory drought-adapted shrub, seemed to be independent of water availability across seasons and sites. Thus, the susceptibility to lowering of GW due to anthropogenic

  13. Use of Natural and Nature-Based Features for Coastal Resilience

    Science.gov (United States)

    Piercy, C.; Bridges, T. S.

    2017-12-01

    Natural and Nature-Based Features (NNBF) have been used for decades to support a variety of objectives in coastal systems. Beach and dune projects have been a longstanding part of flood risk reduction strategies in Europe, the United States and elsewhere. Coastal restoration projects supporting wetlands, seagrass, oysters and other habitats and communities have been undertaken around the world to restore ecosystem functions. In more recent years there has been a growing interest in developing a technically sound engineering approach for integrating NNBF, in combination with conventional flood defense systems (e.g., levees, seawalls, etc.), for more comprehensive and sustainable flood defense systems. This interest was further stimulated by the outcomes of recent storm events, including Hurricanes Katrina and Sandy in the United States, which have given rise to a range of studies and projects focused on the role of coastal landscape features in flood risk management. The global dialogue that has been underway for several years—including within the Engineering with Nature program in the United States—has revealed the demand for an authoritative guidance on the use of NNBF in shoreline management. The U.S. Army Corps of Engineers has initiated a collaborative project involving participants from several countries and organizations representing government, academia, and the private sector to develop international guidelines to inform the planning, design, construction, and operation or NNBF projects to support coastal resilience. This paper will describe the key issues and objectives informing the work of the international team that is developing the guidelines.

  14. Dune field pattern formation and recent transporting winds in the Olympia Undae Dune Field, north polar region of Mars

    OpenAIRE

    Ewing, Ryan C.; Peyret, Aymeric-Pierre B.; Kocurek, Gary; Bourke, Mary

    2010-01-01

    High-Resolution Imaging Science Experiment (HiRISE) imagery of the central Olympia Undae Dune Field in the north polar region of Mars shows a reticulate dune pattern consisting of two sets of nearly orthogonal dune crestlines, with apparent slipfaces on the primary crests, ubiquitous wind ripples, areas of coarse-grained wind ripples, and deflated interdune areas. Geomorphic evidence and dune field pattern analysis of dune crest length, spacing, defect density, and orientation indicates that ...

  15. Coastal habitat and biological community response to dam removal on the Elwha River

    Science.gov (United States)

    Foley, Melissa M.; Warrick, Jonathan A.; Ritchie, Andrew C.; Stevens, Andrew; Shafroth, Patrick B.; Duda, Jeff; Beirne, Matthew M.; Paradis, Rebecca; Gelfenbaum, Guy R.; McCoy, Randall; Cubley, Erin S.

    2017-01-01

    Habitat diversity and heterogeneity play a fundamental role in structuring ecological communities. Dam emplacement and removal can fundamentally alter habitat characteristics, which in turn can affect associated biological communities. Beginning in the early 1900s, the Elwha and Glines Canyon dams in Washington, USA, withheld an estimated 30 million tonnes of sediment from river, coastal, and nearshore habitats. During the staged removal of these dams—the largest dam removal project in history—over 14 million tonnes of sediment were released from the former reservoirs. Our interdisciplinary study in coastal habitats—the first of its kind—shows how the physical changes to the river delta and estuary habitats during dam removal were linked to responses in biological communities. Sediment released during dam removal resulted in over a meter of sedimentation in the estuary and over 400 m of expansion of the river mouth delta landform. These changes increased the amount of supratidal and intertidal habitat, but also reduced the influx of seawater into the pre-removal estuary complex. The effects of these geomorphic and hydrologic changes cascaded to biological systems, reducing the abundance of macroinvertebrates and fish in the estuary and shifting community composition from brackish to freshwater-dominated species. Vegetation did not significantly change on the delta, but pioneer vegetation increased during dam removal, coinciding with the addition of newly available habitat. Understanding how coastal habitats respond to large-scale human stressors—and in some cases the removal of those stressors—is increasingly important as human uses and restoration activities increase in these habitats.

  16. Dietary habits and selenium intake of residents in mountain and coastal communities in Japan.

    Science.gov (United States)

    Miyazaki, Yukiko; Koyama, Hiroshi; Sasada, Yoko; Satoh, Hiroshi; Nojiri, Masami; Suzuki, Shosuke

    2004-10-01

    We used a Simple Food Frequency Questionnaire (SFFQ) in combination with other dietary approaches to estimate the selenium intake from different food groups based on the average long-term diet, in two rural communities in Japan, one in a mountain area and the other in a coastal area. The intake frequencies of rice and wheat products were significantly different in the two districts. The intake frequencies of fish, meat, and eggs, which are rich in selenium, were not significantly different. The mean dietary selenium intake, estimated from the SFFQ and the 24-h recall method, was 82.7 microg/d (n=234) (range 19.2-180.1 microg/d) in the mountain community. The mean dietary selenium intake estimated from the SFFQ and average value of the normal portion size was 118.0 microg/d (n=123) (range 22.6-255.3 microg/d) in the coastal community. These estimated mean values exceeded the Japanese RDA, although the range of daily selenium intake was large. In the mountain community, fish made the largest contribution to dietary selenium intake (48.2% of daily total), followed by eggs (24.3%), and meat (17.0%). In the coastal community, fish accounted for 57.7% of daily total selenium intake, followed by meat (17.5%), and eggs (16.1%). In both districts, the total contribution of rice and wheat products was around 10%. It was found that the contribution of fish to dietary selenium intake was high and the contribution of cereals was low among Japanese.

  17. Last Glacial Maximum Development of Parna Dunes in Panhandle Oklahoma, USA

    Science.gov (United States)

    Johnson, W. C.; Halfen, A. F.; McGowen, S.; Carter, B.; Fine, S.; Bement, L. C.; Simms, A. R.

    2012-12-01

    Though dunefields are a ubiquitous feature of the North American Great Plains, those studied to date have consisted primarily of sand grains. In Beaver County of the Oklahoma panhandle, however, upland dune forms consist of sand-sized aggregates of silt and clay. These aptly named parna dunes occur in two swarms, range in height from 10-15 m, and have asymmetrical dome morphologies with approximate north-south dune orientations. Despite their morphological similarities to sand dunes of the region, their origin and evolution is unknown. Documenting parna dune formation in the Oklahoma panhandle will help improve our understanding of prehistoric landscape instability and climate change, particularly in the central Great Plains where such records are limited. Panhandle parna dunes are typified by Blue Mound, our best documented parna dune thus far. Coring has documented a basal paleosol buried at a depth equivalent to the surrounding landscape—14C ages from this soil indicate its formation about 25-21 ka. The paleosol is a hydric Mollisol with a pronounced C3 isotopic signature reflecting hydric plant communities, rather than the regionally dominated C4 prairie vegetation. Hydric soils are associated with many of the playas on the surrounding landscape today, which suggests that they may have been more prevalent during the LGM. The overlying 8-10 m of parna is low in organic C and high in calcite, with indications of up to ten major episodes of sediment flux, which are documented with magnetic, isotope, soil-stratigraphic, particle-size, and color data. Near-surface luminescence (OSL) ages from Blue Mound are similar to the 14C ages from the basal paleosol, indicating rapid dune construction, with little or no Holocene accumulation of sediment. Marine isotope stage (MIS) 3 loess records indicate that upland areas of the region were relatively stable with attendant widespread pedogenesis prior to development of the parna dunes. At the onset of the LGM, however, the

  18. The concept of community poverty reduction in coastal area of Surabaya based on sustainable livelihood approach

    Science.gov (United States)

    Gai, A. M.; Soewarni, I.; M, M., Sir

    2018-04-01

    Multidimensional poverty becomes a trademark of fisherman community including the community in Surabaya. The fishermen in Surabaya belong to a society with quite apprehensive welfare in all aspects covering economy, social, and environment. Therefore, this research aims to organize poverty reduction concept in coastal area of Surabaya based on sustainable livelihood which assesses poverty through 5 (five) livelihood assets i.e. human asset, natural asset, social asset, physical asset, and financial asset. This research is a qualitative research using rationalistic approach with explorative, descriptive, and perspective nature. Primary data collected using Participatory Poverty Assessment (PPA) and secondary data collected through agency and literature survey. Purposive sampling was employed in getting the sample. Then, the data were analyzed using content analysis, statistics descriptive analysis, and delphi analysis. The results show that sustainable livelihood level in coastal area of Surabaya indicates the human asset is 65% at the SLA level and the lowest is social asset which is 20%, and financial asset is the most affecting factors of poverty in coastal area of Surabaya since the expense for fuel cannot be compared to the fish catched. Community empowerment is the concept proposed to overcome the poverty problems in coastal area of Surabaya.

  19. Single-phase ProtoDUNE, the Prototype of a Single-Phase Liquid Argon TPC for DUNE at the CERN Neutrino Platform

    CERN Document Server

    Cavanna, F; Touramanis, C

    2017-01-01

    ProtoDUNE-SP is the single-phase DUNE Far Detector prototype that is under construction and will be operated at the CERN Neutrino Platform (NP) starting in 2018. It was proposed to the CERN SPSC in June 2015 (SPSC-P-351) and was approved in December 2015 as experiment NP04 (ProtoDUNE). ProtoDUNE-SP, a crucial part of the DUNE effort towards the construction of the first DUNE 10-kt fiducial mass far detector module (17 kt total LAr mass), is a significant experiment in its own right. With a total liquid argon (LAr) mass of 0.77 kt, it represents the largest monolithic single phase LArTPC detector to be built to date. It is housed in an extension to the EHN1 hall in the North Area, where the CERN NP is providing a new dedicated charged-particle test beamline. ProtoDUNE-SP aims to take its first beam data before the LHC long shutdown (LS2) at the end of 2018. ProtoDUNE-SP prototypes the designs of most of the single-phase DUNE far detector module (DUNE-SP) components at a 1:1 scale, with an extrapolation of abo...

  20. Analysis of Stakeholder-Defined Needs in Northeast U.S. Coastal Communities to Determine Gaps in Research Informing Coastal Resilience Planning

    Science.gov (United States)

    Molino, G. D.; Kenney, M. A.; Sutton-Grier, A.; Penn, K.

    2017-12-01

    The impacts of climate change on our coastlines are increasing pressure on communities, ecosystems, infrastructure, and state-to-local economies in the northeastern United States (U.S.). As a result of current or imminent risk of acute and chronic hazards, local, state and regional entities have taken steps to identify and address vulnerabilities to climate change. Decisions to increase coastal infrastructure resilience and grey, green, and cultural infrastructure solutions requires physical, natural, and social science that is useful for decision-making and effective science translation mechanisms. Despite the desire to conduct or fund science that meets the needs of communities, there has been no comprehensive analysis to determine stakeholder-defined research needs. To address this gap, this study conducts a stakeholder needs analysis in northeast U.S. coastal communities to determine gaps in information and translation processes supporting coastal resilience planning. Documents were sourced from local, state, and regional organizations in both the public and private sectors, using the northeast region defined by the third National Climate Assessment. Modeled after Dilling et al. (2015), a deductive coding schema was developed that categorized documents using specific search terms such as "Location and condition of infrastructure" and "Proactive planning". A qualitative document analysis was then executed using NVivo to formally identify patterns and themes present in stakeholder surveys, workshop proceedings, and reports. Initial stakeholder priorities centered around incorporation of climate science into planning and decision making regarding vulnerabilities of infrastructure, enhanced emergency planning and response, and communication of key information.

  1. Yeasts and coliform bacteria of water accumulated in bromeliads of mangrove and sand dune ecosystems of southeast Brazil.

    Science.gov (United States)

    Hagler, A N; Rosa, C A; Morais, P B; Mendonça-Hagler, L C; Franco, G M; Araujo, F V; Soares, C A

    1993-10-01

    Yeasts and coliform bacteria were isolated from water that accumulated in the central cups and adjacent leaf axilae of two bromeliads, Neoregelia cruenta of a coastal sand dune and Quesnelia quesneliana of a mangrove ecosystem near the city of Rio de Janeiro, Brazil. The mean total coliform counts were above 10,000 per 100 mL for waters of both plants, but the mean fecal coliform counts were only 74 per 100 mL for Q. quesneliana and mostly undetected in water from N. cruenta. Of 90 fecal coliform isolates, 51 were typical of Escherichia coli in colony morphology and indol, methyl red, Volges-Proskauer, and citrate (IMViC) tests. Seven representatives of the typical E. coli cultures were identified as this species, but the identifications of nine other coliform bacteria were mostly dubious. The yeast community of N. cruenta was typical of plant surfaces with basidiomycetous yeasts anamorphs, and the black yeast Aureobasidium pullulans was prevalent. Quesnelia quesneliana had a substantial proportion of ascomycetous yeasts and their anamorphs, including a probable new biotype of Saccharomyces unisporus. Our results suggested that the microbial communities in bromeliad waters are typically autochtonous and not contaminants.

  2. Whole Community Resilience: Engaging Multiple Sectors with the Coastal Community Resilience Index and the Climate and Resilience Community of Practice in the Gulf of Mexico

    Science.gov (United States)

    Sempier, T.

    2017-12-01

    Communicating risk due to flooding, sea level rise, storm surge, and other natural hazards is a complex task when attempting to build resilience in coastal communities. There are a number of challenges related to preparing for, responding to, and recovering from coastal storms. Successful resilience planning must include a wide range of sectors including, but not limited to local government, business, non-profit, religious, academia, and healthcare. Years of experience working with communities in the Gulf of Mexico has helped create a process that is both inclusive and effective at bringing the right people to the table and gaining momentum towards resilience efforts. The Coastal Community Resilience Index (CRI), a self-assessment for community leaders, has been implemented in 54 Gulf communities with funding that provides small grant awards to help communities take action to address gaps and vulnerabilities identified in the assessment process. To maintain momentum with resilience actions, the Gulf Climate and Resilience Community of Practice (CoP) encourages local municipality participants to share lessons learned and best practices from their implementation projects in an annual symposium. Recently, both graduate and undergraduate students have been exposed to the CRI and CoP as avenues to work through solutions to complex problems at the local level. In addition, a new generation of high school students has been introduced to the CRI. Their engagement in the process is building a more informed citizenry that will take on the leadership and decision-making roles in the future. Investing in multiple age groups and sectors through the CRI and CoP is building capacity for whole community resilience in the Gulf of Mexico. This presentation will focus on methods that have been successful in the Gulf of Mexico for creating effective change in local municipalities towards resilience actions. Discussion will include decision support tools for engaging local

  3. A case study on dune response to infragravity waves

    Science.gov (United States)

    Li, Wenshan; Wang, Hui; Li, Huan; Wu, Shuangquan; Li, Cheng

    2017-08-01

    A series of numerical simulations were conducted using the process-based model XBeach to investigate dune response under normal and getting rid of infragravity wave conditions with different slopes. Erosion volume upside the dune toe and dune top recession are set as indicators for dune vulnerability as well as defence capacity for its front-beach. Results show that both dune erosion volume and dune top recession decrease with gentler dune slopes. Of all the simulation cases, dune with a face slope of 1/1 lost most sand and supplied most sand for lower-bed. The presence of infragravity waves is validated to be crucial to dune vulnerability. The dune erosion volume is shown to decrease by 44.5%∼61.5% and the dune top recession decreased by 0%∼45.5% correspondingly, in the case that infragravity motion is not taken into account during simulation for different dune slopes.

  4. Coastal monitoring solutions of the geomorphological response of beach-dune systems using multi-temporal LiDAR datasets (Vendée coast, France)

    Science.gov (United States)

    Le Mauff, Baptiste; Juigner, Martin; Ba, Antoine; Robin, Marc; Launeau, Patrick; Fattal, Paul

    2018-03-01

    Three beach and dune systems located in the northeastern part of the Bay of Biscay in France were monitored over 5 years with a time series of three airborne LiDAR datasets. The three study sites illustrate a variety of morphological beach types found in this region. Reproducible monitoring solutions adapted to basic and complex beach and dune morphologies using LiDAR time series were investigated over two periods bounded by the three surveys. The first period (between May 2008 and August 2010) is characterized by a higher prevalence of storm events, and thus has a greater potential for eroding the coast, than the second period (between August 2010 and September 2013). During the first period, the central and northeastern part of the Bay of Biscay was notably impacted by Storm Xynthia, with water levels and wave heights exceeding the 10-year return period and 1-year return period, respectively. Despite differences in dune morphology between the sites, the dune crest (Dhigh) and the dune base (Dlow) are efficiently extracted from each DEM. Based on the extracted dune base, an original shoreline mobility indicator is built displaying a combination of the horizontal and vertical migrations of this geomorphic indicator between two LiDAR datasets. A 'Geomorphic Change Detection' is also completed by computing DEMs of Difference (DoD) resulting in segregated maps of erosion and deposition and sediment budgets. Accounting for the accuracy of LiDAR datasets, a probabilistic approach at a 95% confidence interval is used as a threshold for the Geomorphic Change Detection showing more reliable results. However, caution should be taken when interpreting thresholded maps of changes and sediment budgets because some beach processes may be masked, especially on wide tidal beaches, by only keeping the most significant changes. The results of the shoreline mobility and Geomorphic Change Detection show a high variability in the beach responses between and within the three study

  5. Rip Currents, Mega-Cusps, and Eroding Dunes

    OpenAIRE

    Thornton, E.B.; MacMahan, J.; Sallenger, A.H.

    2006-01-01

    Submitted to Marine Geology 1 November 2006 Dune erosion is shown to occur at the embayment of beach mega-cusps O(200m alongshore) that are associated with rip currents. The beach is the narrowest at the embayment of the mega-cusps allowing the swash of large storm waves coincident with high tides to reach the toe of the dune, to undercut the dune and to cause dune erosion. Field measurements of dune, beach, and rip current morphology are acquired along an 18 km shoreline in southern Mont...

  6. Chronic polyaromatic hydrocarbon (PAH contamination is a marginal driver for community diversity and prokaryotic predicted functioning in coastal sediments

    Directory of Open Access Journals (Sweden)

    Mathilde Jeanbille

    2016-08-01

    Full Text Available Benthic microorganisms are key players in the recycling of organic matter and recalcitrant compounds such as polyaromatic hydrocarbons (PAHs in coastal sediments. Despite their ecological importance, the response of microbial communities to chronic PAH pollution, one of the major threats to coastal ecosystems, has received very little attention. In one of the largest surveys performed so far on coastal sediments, the diversity and composition of microbial communities inhabiting both chronically contaminated and non-contaminated coastal sediments were investigated using high-throughput sequencing on the 18S and 16S rRNA genes. Prokaryotic alpha-diversity showed significant association with salinity, temperature, and organic carbon content. The effect of particle size distribution was strong on eukaryotic diversity. Similarly to alpha-diversity, beta-diversity patterns were strongly influenced by the environmental filter, while PAHs had no influence on the prokaryotic community structure and a weak impact on the eukaryotic community structure at the continental scale. However, at the regional scale, PAHs became the main driver shaping the structure of bacterial and eukaryotic communities. These patterns were not found for PICRUSt predicted prokaryotic functions, thus indicating some degree of functional redundancy. Eukaryotes presented a greater potential for their use as PAH contamination biomarkers, owing to their stronger response at both regional and continental scales.

  7. Learning To Leave: The Irony of Schooling in a Coastal Community...Some Preliminary Findings.

    Science.gov (United States)

    Corbett, Mike

    A study examined the role of education in outmigration from the rural coastal community of Digby Neck, Nova Scotia. Data gathered on 756 Grade 6 students who left Digby Neck Consolidated School between 1957 and 1992 were supplemented by in-depth interviews with 36 of those former students, 12 area educators, and community members. Findings…

  8. Community-based tourism in practice: evidence from three coastal communities in Bohuslän, Sweden

    Directory of Open Access Journals (Sweden)

    Lindström Kristina N.

    2016-09-01

    Full Text Available Local involvement in tourism development is defined as a key issue for sustainable tourism, however it is often questioned and less seldom implemented in reality. Reasons behind this condition are lack of knowledge and practical experience on community-based tourism as a bottom-up approach. In this paper it is argued that local involvement in tourism development is both a democratic right and a strategic destination management tool. The paper scrutinizes a process of collaboration and local participation in a tourism development project within three coastal communities on the Swedish West Coast. A mixed-methods approach was employed in the project with the specific aim of investigating attitudes to the community and tourism development and of involving community stakeholders in exploring alternative avenues of tourism development. The article describes four phases of the process of local involvement in a tourism development project: step 1, formation of a representative project group and negotiation of community-based approach; step 2, consulting local stakeholders and employing a mixed-methods approach; step 3, elaborating results with local stakeholders; step 4, increased community collaboration.

  9. Impact d'une modulation duale sur les performances d'une liaison ...

    African Journals Online (AJOL)

    Le présent document présente la technique de modulation duale Fréquence - Amplitude dans le cas d'une liaison optique du type IM-DD. Ce travail révèle que la modulation duale Fréquence - Amplitude permet de générer un signal à bande latérale unique. Les performances d'une liaison optique IM-DD basée sur cette ...

  10. Rural Education and Out-Migration: The Case of a Coastal Community

    Science.gov (United States)

    Corbett, Michael

    2005-01-01

    In this article, I report on findings from a case study examining the relationship between formal education and out-migration in a Canadian coastal community from the early 1960s to the late 1990s. Although high rates of village-level out-migration were chronic, most migration trajectories were short-range. Contrary to large-scale quantitative…

  11. Establishment, growth and degeneration of Ammophila arenaria in coastal sand dunes

    NARCIS (Netherlands)

    Putten, van der W.H.

    1989-01-01

    Introduction

    This study deals with the establishment, growth, and degeneration of Ammophila arenaria (marram grass), a grass species that dominates the vegetation in coastal foredunes. Following natural

  12. Dune field pattern formation and recent transporting winds in the Olympia Undae Dune Field, north polar region of Mars

    Science.gov (United States)

    Ewing, Ryan C.; Peyret, Aymeric-Pierre B.; Kocurek, Gary; Bourke, Mary

    2010-08-01

    High-Resolution Imaging Science Experiment (HiRISE) imagery of the central Olympia Undae Dune Field in the north polar region of Mars shows a reticulate dune pattern consisting of two sets of nearly orthogonal dune crestlines, with apparent slipfaces on the primary crests, ubiquitous wind ripples, areas of coarse-grained wind ripples, and deflated interdune areas. Geomorphic evidence and dune field pattern analysis of dune crest length, spacing, defect density, and orientation indicates that the pattern is complex, representing two constructional generations of dunes. The oldest and best-organized generation forms the primary crestlines and is transverse to circumpolar easterly winds. Gross bed form-normal analysis of the younger pattern of crestlines indicates that it emerged with both circumpolar easterly winds and NE winds and is reworking the older pattern. Mapping of secondary flow fields over the dunes indicates that the most recent transporting winds were from the NE. The younger pattern appears to represent an influx of sediment to the dune field associated with the development of the Olympia Cavi reentrant, with NE katabatic winds channeling through the reentrant. A model of the pattern reformation based upon the reconstructed primary winds and resulting secondary flow fields shows that the development of the secondary pattern is controlled by the boundary condition of the older dune topography.

  13. Delineating Beach and Dune Morphology from Massive Terrestrial Laser Scanning Data Using the Generic Mapping Tools

    Science.gov (United States)

    Zhou, X.; Wang, G.; Yan, B.; Kearns, T.

    2016-12-01

    Terrestrial laser scanning (TLS) techniques have been proven to be efficient tools to collect three-dimensional high-density and high-accuracy point clouds for coastal research and resource management. However, the processing and presenting of massive TLS data is always a challenge for research when targeting a large area with high-resolution. This article introduces a workflow using shell-scripting techniques to chain together tools from the Generic Mapping Tools (GMT), Geographic Resources Analysis Support System (GRASS), and other command-based open-source utilities for automating TLS data processing. TLS point clouds acquired in the beach and dune area near Freeport, Texas in May 2015 were used for the case study. Shell scripts for rotating the coordinate system, removing anomalous points, assessing data quality, generating high-accuracy bare-earth DEMs, and quantifying beach and sand dune features (shoreline, cross-dune section, dune ridge, toe, and volume) are presented in this article. According to this investigation, the accuracy of the laser measurements (distance from the scanner to the targets) is within a couple of centimeters. However, the positional accuracy of TLS points with respect to a global coordinate system is about 5 cm, which is dominated by the accuracy of GPS solutions for obtaining the positions of the scanner and reflector. The accuracy of TLS-derived bare-earth DEM is primarily determined by the size of grid cells and roughness of the terrain surface for the case study. A DEM with grid cells of 4m x 1m (shoreline by cross-shore) provides a suitable spatial resolution and accuracy for deriving major beach and dune features.

  14. Perfluorinated compounds in infiltrated river rhine water and infiltrated rainwater in coastal dunes.

    Science.gov (United States)

    Eschauzier, Christian; Haftka, Joris; Stuyfzand, Pieter J; de Voogt, Pim

    2010-10-01

    Different studies have shown that surface waters contain perfluorinated compounds (PFCs) in the low ng/L range. Surface waters are used to produce drinking water and PFCs have been shown to travel through the purification system and form a potential threat to human health. The specific physicochemical properties of PFCs cause them to be persistent and some of them to be bioaccumulative and toxic in the environment. This study investigates the evolvement of PFC concentrations in Rhine water and rainwater during dune water infiltration processes over a transect in the dune area of the western part of The Netherlands. The difference between infiltrated river water and rainwater in terms of PFC composition was investigated. Furthermore, isomer profiles were investigated. The compound perfluorobutanesulfonate (PFBS) was found at the highest concentrations of all PFCs investigated, up to 37 ng/L in infiltrated river water (71 ± 13% of ΣPFCs). This is in contrast with the predominant occurrence of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS) reported in literature. The concentrations of PFBS found in infiltrated river Rhine water were significantly higher than those in infiltrated rainwater. For perfluorohexanesulfonate (PFHxS) the opposite was found: infiltrated rainwater contained more than infiltrated river water. The concentrations of PFOA, perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), PFBS, PFOS, and PFHxS in infiltrated river water showed an increasing trend with decreasing age of the water. The relative contribution of the branched PFOA and PFOS isomers to total concentrations of PFOA and PFOS showed a decreasing trend with decreasing age of the water.

  15. Coastal freshwater resources management in the frame of climate change: application to three basins (Italy, Morocco, Portugal)

    Science.gov (United States)

    Masson, E.; Antonellini, M.; Dentinho, T.; Khattabi, A.

    2009-04-01

    Climate change becomes an increasing constraint in IWRM and many effects are expected in coastal watersheds like sea level rise and its consequences (i.e. beach erosion, salt water intrusion, soil salinization, groundwater and surface water pollution…) or water budget changes (i.e. seasonal and inter-annual fluctuations) and an increase of extreme events (i.e. floods, rainfalls and droughts). Beside this physical changes one can also observed the increase of water demand in coastal areas due to population growth and development of tourism activities. Both effects (e.g. physical and socio-economical) must be included into any coastal freshwater management option for a mid-term / long-term approach to set water mass/basin management plans as expected in European countries by the WDF or elsewhere in an IWRM objective. The Waterknow project funded by EraNet-Circle-Med program aims to develop a tool to help decisions makers in the implementation of IWRM plans in coastal areas that will have to cope with climate change effects and socio-economical pressures. This interdisciplinary project is applied to three basins (e.g. Fiumi Uniti Bevano, Italy; Terceira Island, Portugal and Taheddart, Morocco) and seeks to integrate and to develop research achievements in coastal hydrogeology, economical and land use modeling in each basin. In the Fiumi Uniti Bevano basin, a detailed hydrogeological survey was performed during the summer 2008. Twenty auger holes with an average spacing of 350 m where drilled with the objective of determining the top groundwater quality in the coastal aquifer. At the same time, we collected the chemical and physical parameters of the surface waters. The data collected in the field show that a fresh groundwater lens is still present in the aquifer of the backshore area below the coastal dunes and that the surface water is all brackish to salty. In the northern part of the study area, the fresh groundwater lens in the backshore zone is missing, as

  16. Measuring disaster-resilient communities: a case study of coastal communities in Indonesia.

    Science.gov (United States)

    Kafle, Shesh Kanta

    2012-01-01

    Vulnerability reduction and resilience building of communities are central concepts in recent policy debates. Although there are fundamental linkages, and complementarities exist between the two concepts, recent policy and programming has focused more on the latter. It is assumed here that reducing underlying causes of vulnerabilities and their interactions with resilience elements is a prerequisite for obtaining resilience capabilities. An integrated approach, incorporating both the vulnerability and resilience considerations, has been taken while developing an index for measuring disaster-resilient communities. This study outlines a method for measuring community resilience capabilities using process and outcome indicators in 43 coastal communities in Indonesia. An index was developed using ten process and 25 outcome indicators, selected on the basis of the ten steps of the Integrated Community Based Risk Reduction (ICBRR) process, and key characteristics of disaster resilient communities were taken from various literatures. The overall index value of all 43 communities was 63, whereas the process and outcome indicator values were measured as 63 and 61.5 respectively. The core components of this index are process and outcome indicators. The tool has been developed with an assumption that both the process and outcome indicators are equally important in building disaster-resilient communities. The combination of both indicators is an impetus to quality change in the community. Process indicators are important for community understanding, ownership and the sustainability of the programme; whereas outcome indicators are important for the real achievements in terms of community empowerment and capacity development. The process of ICBRR approach varies by country and location as per the level of community awareness and organisational strategy. However, core elements such as the formation of community groups, mobilising those groups in risk assessment and planning

  17. Effects of intake interruptions on dune infiltration systems in the Netherlands, their quantification and mitigation.

    Science.gov (United States)

    Stuyfzand, Pieter J; van der Schans, Martin L

    2018-07-15

    In the coastal dunes of the Western Netherlands, managed aquifer recharge (MAR) is applied for drinking water supply since 1957. The MAR systems belong to the Aquifer Transfer Recovery (ATR) type, because recharge and recovery are operated without interruption. This makes these systems very vulnerable to intake interruptions, which are expected to increase in frequency and duration due to climate change. Such interruptions are problematic, because: (i) groundwater recovery from dunes needs to continue to supply fresh drinking water to the Western Netherlands; (ii) risks of salt water intrusion are high, and (iii) MAR bordering wet dune slacks with an EU Natura 2000 status cannot survive for long without MAR. In this paper, effects of intake stops are discussed and quantified. The hydrological effects consist of the decline of water tables, disappearance of flow-through dune lakes, reservoir depletion, salt water intrusion, disruption of rainwater lenses, and entrapped air hampering a rapid refill of the groundwater reservoir. Water quality effects include changes in (i) redox environment of the flushed aquifer, impacting the behavior of nutrients, calcium, sulfate and organic micro-pollutants, and (ii) the mixing ratio of water types. The main ecological impacts comprise the dying of organisms in recharge ponds and dune lakes, and a decline of biodiversity. Effects of very long intake interruptions (years) are predicted via historical observations during the long overexploitation period (1900-1957) prior to MAR. A closed form analytical solution for safe yield of a semiconfined aquifer is proposed, together with a related upconing risk index. Both also apply to the pumping from any fresh water lens without MAR. Some mitigation strategies are discussed, such as a dual intake, raising the storage capacity, earlier mud removal, and accelerated refilling of the reservoir. A magnitude scale for intake stops (MIS) is proposed. Copyright © 2018 Elsevier B.V. All rights

  18. Controls on desert dune activity - a geospatial approach

    Science.gov (United States)

    Lancaster, N.; Hesse, P. P.

    2017-12-01

    Desert and other inland dunes occur on a wide spectrum of activity (defined loosely as the proportion of the surface area subject to sand movement) from unvegetated to sparsely vegetated "active" dunes through discontinuously vegetated inactive dunes to completely vegetated and degraded dunes. Many of the latter are relicts of past climatic conditions. Although field studies and modeling of the interactions between winds, vegetation cover, and dune activity can provide valuable insights, the response of dune systems to climate change and variability past, present, and future has until now been hampered by the lack of pertinent observational data on geomorphic and climatic boundary conditions and dune activity status for most dune areas. We have developed GIS-based approach that permits analysis of boundary conditions and controls on dune activity at a range of spatial scales from dunefield to global. In this approach, the digital mapping of dune field and sand sea extent has been combined with systematic observations of dune activity at 0.2° intervals from high resolution satellite image data, resulting in four classes of activity. 1 km resolution global gridded datasets for the aridity index (AI); precipitation, satellite-derived percent vegetation cover; and estimates of sand transport potential (DP) were re-sampled for each 0.2° grid cell, and dune activity was compared to vegetation cover, sand transport potential, precipitation, and the aridity index. Results so far indicate that there are broad-scale relationships between dunefield mean activity, climate, and vegetation cover. However, the scatter in the data suggest that other local factors may be at work. Intra-dune field patterns are complex in many cases. Overall, much more work needs to be done to gain a full understanding of controls at different spatial and temporal scales, which can be faciliated by this spatial database.

  19. Coupling bacterioplankton populations and environment to community function in coastal temperate waters

    DEFF Research Database (Denmark)

    Traving, S. J.; Bentzon-Tilia, Mikkel; Knudsen-Leerbeck, H.

    2016-01-01

    Bacterioplankton play a key role in marine waters facilitating processes important for carbon cycling. However, the influence of specific bacterial populations and environmental conditions on bacterioplankton community performance remains unclear. The aim of the present study was to identify...... drivers of bacterioplankton community functions, taking into account the variability in community composition and environmental conditions over seasons, in two contrasting coastal systems. A Least Absolute Shrinkage and Selection Operator (LASSO) analysis of the biological and chemical data obtained from...... surface waters over a full year indicated that specific bacterial populations were linked to measured functions. Namely, Synechococcus (Cyanobacteria) was strongly correlated with protease activity. Both function and community composition showed seasonal variation. However, the pattern of substrate...

  20. The sociological perspective in coastal management and geoengineering approach: effects of hydraulic structures on the resilience of fishing communities (NW Portugal)

    Science.gov (United States)

    Rocha, Fernando; Pires, Ana; Chamine, Helder

    2014-05-01

    The coast plays an important role in global transportation and is the most popular tourist destination around the world. During the years coastal scientists "walking on the shore", have tried to understand the shoreline in relation to the processes that shape it, and its interrelationships with the contiguous superficial marine and terrestrial hinterland environments. Those factors encourage the need for Integrated Coastal Zone Management (ICZM), because of its possible use in identifying coastal management issues to take into account in policy strategies, measures and planning. Therefore this research presents an integrated strategy and a holistic approach to researching and studying coastal areas involving a wide number of sciences including sociology. Because of the numerous types of hazards in coastal areas the only possible response involves a holistic, integrated and long term approach. Combining marine sociological research, resilience and flexibility of a particular coastal community with other scientific fields will help to understand and manage marine social problems. This study also shows an integrative and "eclectic" methodology and adapts it to coastal management. Hence a new integrated coastal geoengineering approach for maritime environments was proposed, which is the core foundation of this approach. Also it was important to incorporate in a broader sense coastal geosciences and geoengineering GIS mapping to this final equation resulting in conceptual models. In Portugal there are several areas buffeted by sea invasions, coastal erosion and severe storms. The Portuguese coastal zone is one of Europe's most vulnerable regarding coastal erosion. The case study presented herein is an example of one of the most vulnerable sites in Portugal in terms of coastal erosion and sea invasions and how the meeting of local fishing community and coastal projects are extremely important. The coastal stretch between Figueira da Foz and Espinho (Centre and NW

  1. Sand dune tracking from satellite laser altimetry

    Science.gov (United States)

    Dabboor, Mohammed

    Substantial problems arise from sand movement in arid and semi-arid countries. Sand poses a threat to infrastructure, agricultural and urban areas. These issues are caused by the encroachment of sand on roads and railway tracks, farmland, towns and villages, and airports, to name a few. Sand movement highly depends on geomorphology including vegetation cover, shape and height of the terrain, and grain size of the sand. However, wind direction and speed are the most important factors that affect efficient sand movement. The direction of the movement depends on the main direction of the wind, but it has been shown that a minimum wind speed is required, e.g. wind gusts, to initiate sand transport. This fact prevents a simple calculation of sand transport from conventional wind data as wind records rarely contain sub-minute intervals masking out any wind gusts. An alternative of predicting sand transport is the direct observation of sand advance by in situ measurements or via satellite. Until recently, satellite imagery was the only means to compare dune shape and position for predicting dune migration over several years. In 2003, the NASA laser altimetry mission ICESat became operational and monitors elevations over all surface types including sand dunes with an accuracy of about 10-20 cm. In this study, ICESat observations from repeat tracks (tracks overlapping eachother within 50 m) are used to derive sand dune advance and direction. The method employs a correlation of the elevation profiles over several dunes and was sucessfully validated with synthetic data. The accuracy of this method is 5 meters of dune advance. One of the most active areas exhibiting sand and dune movement is the area of the Arabian Peninsula. Approximately one-third of the Arabian Peninsula is covered by sand dunes. Different wind regimes (Shamal, Kaus) cause sand dune movement in the selected study area in the eastern part of the Arabian Peninsula between 20-25 degrees North and 45-55 degrees

  2. Evaluation of anthropogenic influence in probabilistic forecasting of coastal change

    Science.gov (United States)

    Hapke, C. J.; Wilson, K.; Adams, P. N.

    2014-12-01

    Prediction of large scale coastal behavior is especially challenging in areas of pervasive human activity. Many coastal zones on the Gulf and Atlantic coasts are moderately to highly modified through the use of soft sediment and hard stabilization techniques. These practices have the potential to alter sediment transport and availability, as well as reshape the beach profile, ultimately transforming the natural evolution of the coastal system. We present the results of a series of probabilistic models, designed to predict the observed geomorphic response to high wave events at Fire Island, New York. The island comprises a variety of land use types, including inhabited communities with modified beaches, where beach nourishment and artificial dune construction (scraping) occur, unmodified zones, and protected national seashore. This variation in land use presents an opportunity for comparison of model accuracy across highly modified and rarely modified stretches of coastline. Eight models with basic and expanded structures were developed, resulting in sixteen models, informed with observational data from Fire Island. The basic model type does not include anthropogenic modification. The expanded model includes records of nourishment and scraping, designed to quantify the improved accuracy when anthropogenic activity is represented. Modification was included as frequency of occurrence divided by the time since the most recent event, to distinguish between recent and historic events. All but one model reported improved predictive accuracy from the basic to expanded form. The addition of nourishment and scraping parameters resulted in a maximum reduction in predictive error of 36%. The seven improved models reported an average 23% reduction in error. These results indicate that it is advantageous to incorporate the human forcing into a coastal hazards probability model framework.

  3. Responses of three-dimensional flow to variations in the angle of incident wind and profile form of dunes: Greenwich Dunes, Prince Edward Island, Canada

    Science.gov (United States)

    Walker, Ian J.; Hesp, Patrick A.; Davidson-Arnott, Robin G. D.; Bauer, Bernard O.; Namikas, Steven L.; Ollerhead, Jeff

    2009-04-01

    these flow responses are enhanced with faster speeds of incident flow and/or more onshore winds. Significant onshore steering of near-surface vectors of flow (to 37°) occurs and is greatest closer to the surface and during highly oblique winds (~ 15° onshore). Therefore, even subtle effects of streamline compression and amplification of flow under alongshore conditions effectively steer flow and sand transport toward the dune. As topographic forcing and steering cause significant, three-dimensional deviations in near-surface properties of flow, most regional-scale and/or two-dimensional models of dune process-response dynamics are insufficient for characterizing coastal and desert dune sediment budgets and morphodynamics. In particular, deflection of sand transport vectors with greater fetch distances than those derived from regional winds may occur. Coincident flow, transport and morphological response data are required to better quantitatively model these processes.

  4. Geomorphology and anthropogenic impact including military constraints in a microtidal wave-dominated embayment in south western Sardinia (Porto Pino beach, SCI ITB040025, Mediterranean Sea). Implications for beach management.

    Science.gov (United States)

    De Muro, Sandro; Buosi, Carla; Pusceddu, Nicola; Frongia, Paolo; Passarella, Marinella; Ibba, Angelo

    2016-04-01

    The coastal zones of the Mediterranean have undergone increasing pressure over the last century. The intensifying coastal development and the increasing tourist impact have led to an intense transformation of the coastlines and adjacent marine areas. The beach and the coastal dune play an important role in protecting the coastline. Thus, the study of its geomorphological evolution and of its anthropic modification is fundamental in order to adopt the best management practices. In this regard, the LIFE Project (LIFE13NAT/IT/001013) SOSS DUNES (Safeguard and management Of South-western Sardinian Dunes) aims to safeguard the dune habitats and the beach system in a site belonging to the Natura 2000 network, an EUwide network of nature protection areas established under the 1992 Habitats Directive. This project is focused on a microtidal wave-dominated embayment located in south western Sardinia (Italy, Mediterranean Sea) called Porto Pino beach comprised in the SCI (Site of Community Importance) "Promontory, dunes and wetland of Porto Pino (ITB040025)". This research aims to investigate the geomorphological processes, the evolution and the main human impacts on Porto Pino beach as an useful tool for both conservation and coastal management. The coastal area of Porto Pino is represented by sandy shorelines extending for a total length of 5 km characterized by a wide primary and secondary dune systems, a backshore wetland lagoon and marsh area arranged parallel to the coastline. This littoral area can be ideally divided into three parts: the first, about 600 m long, in the north-west part characterized by the highest human pressure due to touristic activity on the foredunes and deposition of beach wrack; the second part in the south-east, about 1100 m long, characterized by a complex dune system (primary and secondary foredunes); and the third southernmost part included in a military area, about 3300 m long, characterized by transgressive dune system with low human

  5. Seaweeds: an opportunity for wealth and sustainable livelihood for coastal communities.

    Science.gov (United States)

    Rebours, Céline; Marinho-Soriano, Eliane; Zertuche-González, José A; Hayashi, Leila; Vásquez, Julio A; Kradolfer, Paul; Soriano, Gonzalo; Ugarte, Raul; Abreu, Maria Helena; Bay-Larsen, Ingrid; Hovelsrud, Grete; Rødven, Rolf; Robledo, Daniel

    2014-01-01

    The European, Canadian, and Latin American seaweed industries rely on the sustainable harvesting of natural resources. As several countries wish to increase their activity, the harvest should be managed according to integrated and participatory governance regimes to ensure production within a long-term perspective. Development of regulations and directives enabling the sustainable exploitation of natural resources must therefore be brought to the national and international political agenda in order to ensure environmental, social, and economic values in the coastal areas around the world. In Europe, Portugal requires an appraisal of seaweed management plans while Norway and Canada have developed and implemented coastal management plans including well-established and sustainable exploitation of their natural seaweed resources. Whereas, in Latin America, different scenarios of seaweed exploitation can be observed; each country is however in need of long-term and ecosystem-based management plans to ensure that exploitation is sustainable. These plans are required particularly in Peru and Brazil, while Chile has succeeded in establishing a sustainable seaweed-harvesting plan for most of the economically important seaweeds. Furthermore, in both Europe and Latin America, seaweed aquaculture is at its infancy and development will have to overcome numerous challenges at different levels (i.e., technology, biology, policy). Thus, there is a need for regulations and establishment of "best practices" for seaweed harvesting, management, and cultivation. Trained human resources will also be required to provide information and education to the communities involved, to enable seaweed utilization to become a profitable business and provide better income opportunities to coastal communities.

  6. Response of bacterial community structure to seasonal fluctuation and anthropogenic pollution on coastal water of Alang-Sosiya ship breaking yard, Bhavnagar, India.

    Science.gov (United States)

    Patel, Vilas; Munot, Hitendra; Shouche, Yogesh S; Madamwar, Datta

    2014-06-01

    Bacterial community structure was analyzed from coastal water of Alang-Sosiya ship breaking yard (ASSBY), world's largest ship breaking yard, near Bhavnagar, using 16S rRNA gene sequencing (cultured dependent and culture independent). In clone libraries, total 2324 clones were retrieved from seven samples (coastal water of ASSBY for three seasons along with one pristine coastal water) which were grouped in 525 operational taxonomic units. Proteobacteria was found to be dominant in all samples. In pristine samples, Gammaproteobacteria was found to be dominant, whereas in polluted samples dominancy of Gammaproteobacteria has shifted to Betaproteobacteria and Epsilonproteobacteria. Richness and diversity indices also indicated that bacterial community in pristine sample was the most diverse followed by summer, monsoon and winter samples. To the best of knowledge, this is the first study describing bacterial community structure from coastal water of ASSBY, and it suggests that seasonal fluctuation and anthropogenic pollutions alters the bacterial community structure. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Exploring inner structure of Titan's dunes from Cassini Radar observations

    Science.gov (United States)

    Sharma, P.; Heggy, E.; Farr, T. G.

    2013-12-01

    Linear dunes discovered in the equatorial regions of Titan by the Cassini-Huygens mission are morphologically very similar to many terrestrial linear dune fields. These features have been compared with terrestrial longitudinal dune fields like the ones in Namib desert in western Africa. This comparison is based on the overall parallel orientation of Titan's dunes to the predominant wind direction on Titan, their superposition on other geomorphological features and the way they wrap around topographic obstacles. Studying the internal layering of dunes has strong implications in understanding the hypothesis for their origin and evolution. In Titan's case, although the morphology of the dunes has been studied from Cassini Synthetic Aperture Radar (SAR) images, it has not been possible to investigate their internal structure in detail as of yet. Since no radar sounding data is available for studying Titan's subsurface yet, we have developed another technique to examine the inner layering of the dunes. In this study, we utilize multiple complementary radar datasets, including radar imaging data for Titan's and Earth's dunes and Ground Penetrating Radar (GPR)/radar sounding data for terrestrial dunes. Based on dielectric mixing models, we suggest that the Cassini Ku-band microwaves should be able to penetrate up to ~ 3 m through Titan's dunes, indicating that the returned radar backscatter signal would include contributions from both surface and shallow subsurface echoes. This implies that the shallow subsurface properties can be retrieved from the observed radar backscatter (σ0). In our analysis, the variation of the radar backscatter as a function of dune height is used to provide an insight into the layering in Titan's dunes. We compare the variation of radar backscatter with elevation over individual dunes on Titan and analogous terrestrial dunes in three sites (Great Sand Sea, Siwa dunes and Qattaniya dunes) in the Egyptian Sahara. We observe a strong, positive

  8. New perspectives on the occupation of Hatuana dune site, Ua Huka, Marquesas Islands

    International Nuclear Information System (INIS)

    Molle, G.; Conte, E.

    2011-01-01

    New archaeological excavations were conducted in 2009 in the Hatuana dune site, Ua Huka, Marquesas archipelago (French Polynesia). The objectives of this research were to determine the complete stratigraphy of the western section of the site, and to obtain charcoal samples for radiocarbon dating. The results are presented here, updating previous dates by E. Conte, and enhancing our understanding of the place of the Hatuana coastal area in the island's prehistory. The main occupation occurred during a period of warfare, suggesting that the place was used to control and prevent enemy attacks. (author). 24 refs., 5 figs., 1 tab.

  9. Understanding the interactions between Social Capital, climate change, and community resilience in Gulf of Mexico coastal counties

    Science.gov (United States)

    Young, C.; Blomberg, B.; Kolker, A.; Nguyen, U.; Page, C. M.; Sherchan, S. P.; Tobias, V. D.; Wu, H.

    2017-12-01

    Coastal communities in the Gulf of Mexico are facing new and complex challenges as their physical environment is altered by climate warming and sea level rise. To effectively prepare for environmental changes, coastal communities must build resilience in both physical structures and social structures. One measure of social structure resilience is how much social capital a community possesses. Social capital is defined as the connections among individuals which result in networks with shared norms, values and understandings that facilitate cooperation within or among groups. Social capital exists in three levels; bonding, bridging and linking. Bonding social capital is a measure of the strength of relationships amongst members of a network who are similar in some form. Bridging social capital is a measure of relationships amongst people who are dissimilar in some way, such as age, education, or race/ethnicity. Finally Linking social capital measures the extent to which individuals build relationships with institutions and individuals who have relative power over them (e.g local government, educational institutions). Using census and American Community Survey data, we calculated a Social Capital index value for bonding, bridging and linking for 60 Gulf of Mexico coastal counties for the years 2000, and 2010 to 2015. To investigate the impact of social capital on community resilience we coupled social capital index values with physical datasets of land-use/land cover, sea level change, climate, elevation and surface water quality for each coastal county in each year. Preliminary results indicate that in Gulf of Mexico coastal counties, increased bonding social capital results in decreased population change. In addition, we observed a multi-year time lag in the effect of increased bridging social capital on population stability, potentially suggesting key linkages between the physical and social environment in this complex coupled-natural human system. This

  10. Observations of Scour and Transport at Coastal Structures from the 2011 Tohoku Tsunami - Implications for Flow in Natural Terrain

    Science.gov (United States)

    Petroff, C. M.

    2011-12-01

    Before the March 11, 2011 Tohoku tsunami, many communities along the Japan coast had shore protection barriers, some designed specifically to provide protection from tsunamis and others for typhoon and storm surge protection. A vast number of these structures were overtopped, damaged or destroyed by the high inundation and currents generated in the tsunami. Observations are presented about scour features at man-made coastal structures in the Tohoku region as well as the hydraulic transport of debris from these structures. Along with providing lessons for structure design and maintenance, these observations have implications for hydraulic transport in natural terrain, not only at hard points such as rock outcrops but also at other features such as river mouths, barrier islands and coastal dunes. As an example, Photo 1 shows the overtopping flow at the seawall at Noda, in the Iwate prefecture. From the point of view of hydraulics the type of flow seen in the photo is more like that at an in-line weir or spillway than the wave conditions for which the structure was designed. On the lee or downstream side of such structures, the flow is supercritical resulting in a supercritical to subcritical transition near the landward toe of the seawall. High flow velocities along with increased pore pressure and overturning flow create very deep scour in these locations Such as the zone clearly seen in Photo 2 behind the seawall at the Sendai airport. It is anticipated that similar hydraulic conditions would occur for flow over a high coastal dune ridge where the ridge would act as a flow control point and locally high velocities on the landward side of the ridge would result in high erosion and scour. Other examples are given.

  11. Quantifying energy and water fluxes in dry dune ecosystems of the Netherlands

    Science.gov (United States)

    Voortman, B. R.; Bartholomeus, R. P.; van der Zee, S. E. A. T. M.; Bierkens, M. F. P.; Witte, J. P. M.

    2015-09-01

    Coastal and inland dunes provide various ecosystem services that are related to groundwater, such as drinking water production and biodiversity. To manage groundwater in a sustainable manner, knowledge of actual evapotranspiration (ETa) for the various land covers in dunes is essential. Aiming at improving the parameterization of dune vegetation in hydrometeorological models, this study explores the magnitude of energy and water fluxes in an inland dune ecosystem in the Netherlands. Hydrometeorological measurements were used to parameterize the Penman-Monteith evapotranspiration model for four different surfaces: bare sand, moss, grass and heather. We found that the net longwave radiation (Rnl) was the largest energy flux for most surfaces during daytime. However, modeling this flux by a calibrated FAO-56 Rnl model for each surface and for hourly time steps was unsuccessful. Our Rnl model, with a novel submodel using solar elevation angle and air temperature to describe the diurnal pattern in radiative surface temperature, improved Rnl simulations considerably. Model simulations of evaporation from moss surfaces showed that the modulating effect of mosses on the water balance is species-dependent. We demonstrate that dense moss carpets (Campylopus introflexus) evaporate more (5 %, +14 mm) than bare sand (total of 258 mm in 2013), while more open-structured mosses (Hypnum cupressiforme) evaporate less (-30 %, -76 mm) than bare sand. Additionally, we found that a drought event in the summer of 2013 showed a pronounced delayed signal on lysimeter measurements of ETa for the grass and heather surfaces, respectively. Due to the desiccation of leaves after the drought event, and their feedback on the surface resistance, the potential evapotranspiration in the year 2013 dropped by 9 % (-37 mm) and 10 % (-61 mm) for the grass and heather surfaces, respectively, which subsequently led to lowered ETa of 8 % (-29 mm) and 7 % (-29 mm). These feedbacks are of importance for

  12. Community Resilience to Cyclone Disasters in Coastal Bangladesh

    Directory of Open Access Journals (Sweden)

    Bayes Ahmed

    2016-08-01

    Full Text Available Bangladesh is one of the poorest and most disaster-prone countries in the world. To address both problems simultaneously, sustainable livelihoods (SL could be better connected with disaster risk reduction (DRR. For this purpose, one initiative implemented in Bangladesh is called the Vulnerability to Resilience (V2R programme which ran from 2013 to 2016. This programme was primarily initiated and funded by the British Red Cross in a consortium with the Swedish Red Cross and the German Red Cross. This article presents the first evaluation of the V2R programme with three objectives. The first objective was to measure whether the selected communities have achieved community resilience characteristics as defined by the programme. The second objective was to conduct a cost-benefit analysis for the intervention. The third objective was to analyse V2R’s impact on the communities in terms of DRR and SL. Community-based focus group discussions and household-based surveys were conducted before and after the intervention (2013–2016 in two coastal communities in Patuakhali district, Nowapara and Pashurbunia. The analysis found that community members are now engaged with many hazard-resilient and vulnerability-reducing livelihood activities, using SL to implement DRR, yet these approaches were almost absent prior to V2R. Consequently, the communities have achieved resilience characteristics, being more well-organized and better connected; having better access to infrastructure, services, and economic opportunities; are more knowledgeable and healthier; and are better managing their available resources. Critiques of the concepts are discussed, although in this case, DRR based on SL has shown positive results, exactly as development theory suggests.

  13. Future DUNE constraints on EFT

    Science.gov (United States)

    Falkowski, Adam; Grilli di Cortona, Giovanni; Tabrizi, Zahra

    2018-04-01

    In the near future, fundamental interactions at high-energy scales may be most efficiently studied via precision measurements at low energies. A universal language to assemble and interpret precision measurements is the so-called SMEFT, which is an effective field theory (EFT) where the Standard Model (SM) Lagrangian is extended by higher-dimensional operators. In this paper we investigate the possible impact of the DUNE neutrino experiment on constraining the SMEFT. The unprecedented neutrino flux offers an opportunity to greatly improve the current limits via precision measurements of the trident production and neutrino scattering off electrons and nuclei in the DUNE near detector. We quantify the DUNE sensitivity to dimension-6 operators in the SMEFT Lagrangian, and find that in some cases operators suppressed by an O(30) TeV scale can be probed. We also compare the DUNE reach to that of future experiments involving atomic parity violation and polarization asymmetry in electron scattering, which are sensitive to an overlapping set of SMEFT parameters.

  14. The Single-Phase ProtoDUNE Technical Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Abi, B. [Univ. of Padova (Italy); et al.

    2017-06-21

    ProtoDUNE-SP is the single-phase DUNE Far Detector prototype that is under construction and will be operated at the CERN Neutrino Platform (NP) starting in 2018. ProtoDUNE-SP, a crucial part of the DUNE effort towards the construction of the first DUNE 10-kt fiducial mass far detector module (17 kt total LAr mass), is a significant experiment in its own right. With a total liquid argon (LAr) mass of 0.77 kt, it represents the largest monolithic single-phase LArTPC detector to be built to date. It's technical design is given in this report.

  15. Morphological Modeling of a Low-Dune Barrier Headland System's Response to Hurricane Forcing Before and After a Large Scale Restoration

    Science.gov (United States)

    Johnson, C.; Chen, Q. J.

    2017-12-01

    Coastal barrier landforms serve as the first line of defense against oceanic and meteorological forcing. Widespread recognition of this function has prompted coastal managers to adopt systematic restoration programs. The state of Louisiana has, in response to its critically eroding shorelines (Byrnes et al., 2017), implemented 30 barrier island and headland restoration projects over the past three decades. The Caminada Headlands Beach and Dune Restoration Project, completed in 2016, restored 22.5 kilometers of Louisiana's coastline by elevating the cross-shore profile and placing approximately 250,000 m3 of sediment within the back- and foreshore. Interventions of this magnitude are significant perturbations to the local sediment budget and geomorphodynamic equilibrium. In Louisiana, an important question is the immediate fate of placed sediment transported during the passage of a hurricane, as the potential to ultimately retain this sediment is influenced by the location of its deposition. The direction of net sediment transport (on- or offshore) depends mainly on the elevation of the storm surge relative to the dune crest, but also on the evolution of the cross-shore water surface gradient and the spatial configuration of biogeophysical properties and hard-structures (Sherwood et al., 2014; Smallegan et al., 2016) . Prior to its restoration, the Caminada headlands were generally of low elevation with the majority of dune crest extending less than 50 cm above MHW and several active breaches. Hurricanes Gustav (2008) and Isaac (2012) made landfall directly on the headlands with inundating storm surges that resulted in observed overwash deposition (Doran et al, 2009; Guy et al, 2013), i.e. landward directed sediment transport and deposition. An open-source process-based morphological model (XBeach) is used to study hurricane induced sediment transport for both pre- and post-restoration of the Caminada headlands. Hindcast pre-restoration simulations of Gustav's and

  16. Rip currents, mega-cusps, and eroding dunes

    Science.gov (United States)

    Thornton, E.B.; MacMahan, J.; Sallenger, A.H.

    2007-01-01

    Dune erosion is shown to occur at the embayment of beach mega-cusps O(200 m alongshore) that are associated with rip currents. The beach is the narrowest at the embayment of the mega-cusps allowing the swash of large storm waves coincident with high tides to reach the toe of the dune, to undercut the dune and to cause dune erosion. Field measurements of dune, beach, and rip current morphology are acquired along an 18 km shoreline in southern Monterey Bay, California. This section of the bay consists of a sandy shoreline backed by extensive dunes, rising to heights exceeding 40 m. There is a large increase in wave height going from small wave heights in the shadow of a headland, to the center of the bay where convergence of waves owing to refraction over the Monterey Bay submarine canyon results in larger wave heights. The large alongshore gradient in wave height results in a concomitant alongshore gradient in morphodynamic scale. The strongly refracted waves and narrow bay aperture result in near normal wave incidence, resulting in well-developed, persistent rip currents along the entire shoreline. The alongshore variations of the cuspate shoreline are found significantly correlated with the alongshore variations in rip spacing at 95% confidence. The alongshore variations of the volume of dune erosion are found significantly correlated with alongshore variations of the cuspate shoreline at 95% confidence. Therefore, it is concluded the mega-cusps are associated with rip currents and that the location of dune erosion is associated with the embayment of the mega-cusp.

  17. Effects of Biochar Blends on Microbial Community Composition in Two Coastal Plain Soils

    Directory of Open Access Journals (Sweden)

    Thomas F. Ducey

    2015-11-01

    Full Text Available The amendment of soil with biochar has been demonstrated to have an effect not only on the soil physicochemical properties, but also on soil microbial community composition and activity. Previous reports have demonstrated significant impacts on soil microbial community structure. These impacts are modulated not only by the biochar composition, but also on the soil’s physicochemical characteristics. This indicates that soil characteristics must be considered prior to biochar amendment. A significant portion of the soils of the southeastern coastal plain are severely degraded and, therefore, candidates for biochar amendment to strengthen soil fertility. In this study we focused on two common soil series in the southeastern coastal plain, utilizing feedstocks endemic to the area. We chose feedstocks in four ratios (100% pine chip; 80:20 mixture of pine chip to poultry litter; 50:50 mixture of pine chip to poultry litter; 100% poultry litter prior to pyrolysis and soil amendment as a biochar product. Soil was analyzed for bioavailable nutrients via Mehlich-1 extractions, as well as microbial community composition using phospholipid fatty acid analysis (PLFA. Our results demonstrated significant shifts in microbial community composition in response to biochar amendment, the effects of which were greatest with 100% poultry litter biochar. Strong relationships between PLFAs and several Mehlich-1 extractable nutrients (Al, Cu, Fe, and P were observed.

  18. Effects of sandbar openings on the zooplankton community of coastal lagoons with different conservation status

    Directory of Open Access Journals (Sweden)

    Rayanne Barros Setubal

    Full Text Available AIM: Artificial sandbar openings are a common management practice in coastal lagoons but they can be a threat when negative effects to the quality of water and to the aquatic biota are observed. The current study compared sandbar opening effects in two coastal lagoons located close to each other, but differing on trophic status and on sandbar openings' background. METHODS:Limnological variables and zooplankton community were recorded monthly during one year before and one year after sandbar openings that occurred in the same month for both lagoons, giving 24 samples. We compared the effects of sandbar opening on response variables, according to the two types of system. RESULTS: The sandbar openings determined changes in some limnological features - depth and salinity - but such effects were different in the two types of system. The zooplankton structure displayed dramatic changes in the eutrophic and commonly opened lagoon. The occurrence and abundance of some species were closely related to changes in limnological variables. CONCLUSIONS: Our data indicated that zooplankton communities are more resistant to sandbar openings in coastal lagoons historically less disturbed. The direction and magnitude of changes promoted by sandbar openings might be specific to each lagoon, due to different backgrounds of disturbances that, in the long term, modify the water quality and the structure of zooplankton communities, and consequently, their resistance and resilience.

  19. Natural and human controls of the Holocene evolution of the beach, aeolian sand and dunes of Caesarea (Israel)

    Science.gov (United States)

    Roskin, J.; Sivan, D.; Shtienberg, G.; Roskin, E.; Porat, N.; Bookman, R.

    2015-12-01

    The study focuses on the Holocene appearance, chronology and drivers of beach sand deposition and inland aeolian sand transport around the Roman-Byzantine ruins of Caesarea, Israel. Beach sand, sand sheets, nebkha, linear and transverse dunes as well as parabolic and transverse interdunes along two transects were sampled in the current study down to their substrate. Sixteen new optically stimulated luminescence ages cluster at ∼5.9-3.3 ka, ∼1.2-1.1 ka (800-900 AD) and ∼190-120 years ago (1825-1895 AD) indicating times of middle and late Holocene sand sheet depositions and historical dune stabilization. The first age cluster indicates that beach sand accumulated when rates of global sea level rise declined around 6-5 ka. Until ∼4 ka sand sheets encroached up to 2.5 km inland. Historical and archaeological evidence points to sand mobilization since the first century AD. Sand sheets dating to 1.2-1.1 ka, coevally found throughout the dunefield represent sand stabilization due to vegetation reestablishment attributed to gradual and fluctuating decline in human activity from the middle Early Islamic period until the 10th century. Historical and chronological evidence of the existence of transverse and coppice dunes from the 19th century suggest that dunes only formed in the last few centuries. The study illustrates the initial role of natural processes, in this case decline in global sea level rise and the primary and later role of fluctuating human activity upon coastal sand mobility. The study distinguishes between sand sheets and dunes and portrays them as sensors of environmental changes.

  20. Multi-spatial analysis of aeolian dune-field patterns

    Science.gov (United States)

    Ewing, Ryan C.; McDonald, George D.; Hayes, Alex G.

    2015-07-01

    Aeolian dune-fields are composed of different spatial scales of bedform patterns that respond to changes in environmental boundary conditions over a wide range of time scales. This study examines how variations in spatial scales of dune and ripple patterns found within dune fields are used in environmental reconstructions on Earth, Mars and Titan. Within a single bedform type, different spatial scales of bedforms emerge as a pattern evolves from an initial state into a well-organized pattern, such as with the transition from protodunes to dunes. Additionally, different types of bedforms, such as ripples, coarse-grained ripples and dunes, coexist at different spatial scales within a dune-field. Analysis of dune-field patterns at the intersection of different scales and types of bedforms at different stages of development provides a more comprehensive record of sediment supply and wind regime than analysis of a single scale and type of bedform. Interpretations of environmental conditions from any scale of bedform, however, are limited to environmental signals associated with the response time of that bedform. Large-scale dune-field patterns integrate signals over long-term climate cycles and reveal little about short-term variations in wind or sediment supply. Wind ripples respond instantly to changing conditions, but reveal little about longer-term variations in wind or sediment supply. Recognizing the response time scales across different spatial scales of bedforms maximizes environmental interpretations from dune-field patterns.

  1. The role of sexual vs. asexual recruitment of Artemisia wudanica in transition zone habitats between inter-dune lowlands and active dunes in Inner Mongolia, China

    Science.gov (United States)

    Wang, Yongcui; Alberto, Busso Carlos; Jiang, Deming; Ala, Musa; Li, Xuehua; Zhou, Quanlai; Lin, Jixiang; Ren, Guohua; Jia, Lian

    2016-04-01

    Artemisia wudanica is an endemic, perennial, pioneering psammophyte species in the sand dune ecosystems of western Horqin Sand Land in northern China. However, no studies have addressed how sexual and asexual reproduction modes of A. wudanica perform at the transitional zones between active dune inter-dune lowlands and active dunes. In early spring, quadrats were randomly set up in the study area to monitor surviving seedling and/or ramet density and frequency coming from sexual/asexual reproduction of A. wudanica. Iron sticks were inserted near each quadrat to determine wind erosion intensity (WE). Additionally, soil samples were collected nearby each quadrat to test for soil moisture (SM), organic matter (OM) and pH. Surviving seedlings of A. wudanica showed an inverse response in comparison with ramets to SM, OM and WE. Soil moisture showed the most positive effect, and WE the negative effect, on surviving, sexual reproduction seedlings. Contrarily, WE had the most positive effect, and SM the negative effect, on asexual reproduction ramets. This suggests that increases in SM and decreases in WE should benefit recruitment of A. wudanica seedlings. On the contrary, ramets coming from asexual reproduction showed a different response to environmental factors in transition zone habitats. While SM was not a key constraint for the survival of seedlings, they showed a better, positive response to wind erosion environments. Overall, various study environmental parameters could be improved to foster A. wudanica invasion and settlement in the plant community through different reproductive modes, thereby promoting vegetation restoration and rehabilitation.

  2. Dynamics of a cliff top dune

    Science.gov (United States)

    Rasmussen, K. R.

    2012-12-01

    Morphological changes during more than 100 years have been investigated for a cliff-top dune complex at Rubjerg at the Danish North Sea coast. Here the lower 50 m of the cliff front is composed of Pleistocene steeply inclined floes of silt and clay with coarse sand in between which gives it a saw-tooth appearance. On top of this the dunes are found for several kilometres along the coastline. Due to erosion by the North Sea the cliff has retreated about 120 m between approximately 1880 and 1970 as indicated from two national surveys, and recent GPS-surveys indicate that erosion is continuing at a similar rate. Nevertheless the cliff top dune complex has survived, but its morphology has undergone some changed. The old maps indicate that around 1880 the dune complex was composed of several up to about 20 m high dunes streamlined in the East-West direction which is parallel to the prevailing wind direction. When protective planting started during the first half of the 20th Century the cliff top dunes gradually merged together forming a narrow, tall ridge parallel to the shore line with the highest part reaching about 90 m near 1970. In 1993 the highest points along the ridge was almost 95 m high, but then the protective planting was considerably reduced and recent annual GPS-surveys indicate that the dunes respond quickly to this by changing their morphology towards the original appearance. It is remarkable that despite the mass wasting caused by the constant erosion of the cliff front the dunes have remained more or less intact. Theoretical studies of hill flow indicate given the proper geometry of the cliff then suspension of even coarse grains can be a very effective agent for carrying sand from the exposed parts of the cliff front to and beyond the cliff-top. Mostly the sand grains are deposited within some hundred meters downwind of the cliff dune while silt is often carried more than 10 km inland. Field observations indicate that where the dislodged floes and

  3. Feeding type affects microplastic ingestion in a coastal invertebrate community.

    Science.gov (United States)

    Setälä, Outi; Norkko, Joanna; Lehtiniemi, Maiju

    2016-01-15

    Marine litter is one of the problems marine ecosystems face at present, coastal habitats and food webs being the most vulnerable as they are closest to the sources of litter. A range of animals (bivalves, free swimming crustaceans and benthic, deposit-feeding animals), of a coastal community of the northern Baltic Sea were exposed to relatively low concentrations of 10 μm microbeads. The experiment was carried out as a small scale mesocosm study to mimic natural habitat. The beads were ingested by all animals in all experimental concentrations (5, 50 and 250 beads mL(-1)). Bivalves (Mytilus trossulus, Macoma balthica) contained significantly higher amounts of beads compared with the other groups. Free-swimming crustaceans ingested more beads compared with the benthic animals that were feeding only on the sediment surface. Ingestion of the beads was concluded to be the result of particle concentration, feeding mode and the encounter rate in a patchy environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Pattern or process? Evaluating the peninsula effect as a determinant of species richness in coastal dune forests.

    Directory of Open Access Journals (Sweden)

    Pieter I Olivier

    Full Text Available The peninsula effect predicts that the number of species should decline from the base of a peninsula to the tip. However, evidence for the peninsula effect is ambiguous, as different analytical methods, study taxa, and variations in local habitat or regional climatic conditions influence conclusions on its presence. We address this uncertainty by using two analytical methods to investigate the peninsula effect in three taxa that occupy different trophic levels: trees, millipedes, and birds. We surveyed 81 tree quadrants, 102 millipede transects, and 152 bird points within 150 km of coastal dune forest that resemble a habitat peninsula along the northeast coast of South Africa. We then used spatial (trend surface analyses and non-spatial regressions (generalized linear mixed models to test for the presence of the peninsula effect in each of the three taxa. We also used linear mixed models to test if climate (temperature and precipitation and/or local habitat conditions (water availability associated with topography and landscape structural variables could explain gradients in species richness. Non-spatial models suggest that the peninsula effect was present in all three taxa. However, spatial models indicated that only bird species richness declined from the peninsula base to the peninsula tip. Millipede species richness increased near the centre of the peninsula, while tree species richness increased near the tip. Local habitat conditions explained species richness patterns of birds and trees, but not of millipedes, regardless of model type. Our study highlights the idiosyncrasies associated with the peninsula effect-conclusions on the presence of the peninsula effect depend on the analytical methods used and the taxon studied. The peninsula effect might therefore be better suited to describe a species richness pattern where the number of species decline from a broader habitat base to a narrow tip, rather than a process that drives species

  5. Aeolian sedimentary processes at the Bagnold Dunes, Mars: Implications for modern dune dynamics and sedimentary structures in the aeolian stratigraphic record of Mars

    Science.gov (United States)

    Ewing, Ryan C.; Bridges, Nathan T.; Sullivan, Rob; Lapotre, Mathieu G. A.; Fischer, Woodward W.; Lamb, Mike P.; Rubin, David M.; Lewis, Kevin W.; Gupta, Sanjeev

    2016-04-01

    Wind-blown sand dunes are ubiquitous on the surface of Mars and are a recognized component of the martian stratigraphic record. Our current knowledge of the aeolian sedimentary processes that determine dune morphology, drive dune dynamics, and create aeolian cross-stratification are based upon orbital studies of ripple and dune morphodynamics, rover observations of stratification on Mars, Earth analogs, and experimental and theoretical studies of sand movement under Martian conditions. In-situ observations of sand dunes (informally called the Bagnold Dunes) by Curiosity Rover in Gale Crater, Mars provide the first opportunity to make observations of dunes from the grain-to-dune scale thereby filling the gap in knowledge between theory and orbital observations and refining our understanding of the martian aeolian stratigraphic record. We use the suite of cameras on Curiosity, including Navigation Camera (Navcam), Mast Camera (Mastcam) and Mars Hand Lens Imager (MAHLI), to make observations of the Bagnold Dunes. Measurements of sedimentary structures are made where stereo images are available. Observations indicate that structures generated by gravity-driven processes on the dune lee slopes, such as grainflow and grainfall, are similar to the suite of aeolian sedimentary structures observed on Earth and should be present and recognizable in Mars' aeolian stratigraphic record. Structures formed by traction-driven processes deviate significantly from those found on Earth. The dune hosts centimeter-scale wind ripples and large, meter-scale ripples, which are not found on Earth. The large ripples migrate across the depositional, lee slopes of the dune, which implies that these structures should be present in Mars' stratigraphic record and may appear similar to compound-dune stratification.The Mars Science Laboratory Curiosity Rover Team is acknowledged for their support of this work.

  6. Modelling climate change effects on a dutch coastal groundwater system using airborne electromagnetic measurements

    NARCIS (Netherlands)

    Faneca S̀anchez, M.; Gunnink, J.L.; Baaren, E.S. van; Oude Essink, G.H.P.; Siemon, B.; Auken, E.; Elderhorst, W.; Louw, P.G.B. de

    2012-01-01

    The forecast of climate change effects on the groundwater system in coastal areas is of key importance for policy makers. The Dutch water system has been deeply studied because of its complex system of low-lying areas, dunes, land won to the sea and dikes, but nowadays large efforts are still being

  7. Aeolian dune sediment flux heterogeneity in Meridiani Planum, Mars.

    Science.gov (United States)

    Chojnacki, Matthew; Urso, Anna; Fenton, Lori K; Michaels, Timothy I

    2017-06-01

    It is now known unambiguously that wind-driven bedform activity is occurring on the surface of Mars today, including early detections of active sand dunes in Meridiani Planum's Endeavour crater. Many of these reports are only based on a few sets of observations of relatively isolated bedforms and lack regional context. Here, we investigate aeolian activity across central Meridiani Planum and test the hypothesis that dune sites surrounding Endeavour crater are also active and part of region-wide sediment migration driven by northwesterly winds. All 13 dune fields investigated clearly showed evidence for activity and the majority exhibited dune migration (average rates of 0.6 m/Earth-year). Observations indicate substantial geographic and temporal heterogeneity of dune crest fluxes across the area and per site. Locations with multiple time steps indicate dune sand fluxes can vary by a factor of five, providing evidence for short periods of rapid migration followed by near-stagnation. In contrast, measurements at other sites are nearly identical, indicating that some dunes are in a steady-state as they migrate. The observed sediment transport direction was consistent with a regional northeasterly-to-northwesterly wind regime, revealing more variations than were appreciated from earlier, more localized studies. Craters containing shallow, degraded, flat-floored interiors tended to have dunes with high sediment fluxes/activity, whereas local kilometer-scale topographic obstructions (e.g., central peaks, yardangs) were found to be inversely correlated with dune mobility. Finally, the previous, more limited detections of dune activity in Endeavour crater have been shown to be representative of a broader, region-wide pattern of dune motion.

  8. An index to determine vulnerability of communities in a coastal zone: a case study of Baler, Aurora, Philippines.

    Science.gov (United States)

    Orencio, Pedcris M; Fujii, Masahiko

    2013-02-01

    A coastal community vulnerability index (CCVI) was constructed to evaluate the vulnerability of coastal communities (Buhangin, Pingit, Reserva, Sabang, and Zabali) in the municipality of Baler, Aurora, Philippines. This index was composed of weighted averages of seven vulnerability factors namely geographical, economic and livelihood, food security, environmental, policy and institutional, demographic, and capital good. Factor values were computed based on scores that described range of conditions that influence communities' susceptibility to hazard effects. Among the factors evaluated, economic and livelihood, policy and institutional and food security contributed to CCVI across communities. Only small variations on CCVI values (i.e., 0.47-0.53) were observed as factor values cancelled out one another during combination process. Overall, Sabang received the highest CCVI, which was contributed mainly by geographical and demographic factors. This technique to determine factors that influenced communities' vulnerability can provide information for local governments in enhancing policies on risk mitigation and adaptation.

  9. Soil-landscape development and late Quaternary environmental change in coastal Estremadura, Portugal

    Science.gov (United States)

    Daniels, Michael; Haws, Jonathan; Benedetti, Michael; Bicho, Nuno

    2015-04-01

    This poster integrates soil-landscape analysis with archaeological survey and paleoenvironmental reconstruction. Soils in surface and buried contexts in Estremadura, Portugal, provide evidence of landscape stability and instability, relative age relationships between landforms, and general paleoenvironmental conditions during the late Quaternary. These factors provide insight into the distribution and condition of Paleolithic archaeological sites and help understand the record of human settlement in the region. Late Pleistocene and Holocene dunes extend inland approximately 10 km from coastal source regions. Surface soils in Holocene dunes under maritime pine (Pinus pinaster) forest exhibit A, E, C/Bh and A, C horizon sequences and classify as Quartzipsamments. Surface soils in late Pleistocene dunes exhibit A, E, Bh, Bhs, Bs horizon sequences and classify as Haplorthods. Both Pleistocene and Holocene dunes commonly bury a heavily weathered soil formed in calcareous sandstone. The boundary between underlying buried soils and overlying surface soils is characterized by a lag deposit of medium to coarse, moderately-rounded gravels, underlain immediately by subsurface Bt and Bss horizons. The lag deposit and absence of buried A horizons both indicate intense and/or prolonged surface erosion prior to burial by late Quaternary dunes. Soil-geomorphic relationships therefore suggest at least two distinct episodes of dune emplacement and subsequent landscape stability following an extensive episode late Pleistocene landscape instability and soil erosion. A conceptual model of soil-landscape evolution through the late Quaternary and Holocene results from the integration of soil profile data, proxy paleoenvironmental data, and the partial record of human settled as revealed in the archaeological record.

  10. Sand Dunes with Frost

    Science.gov (United States)

    2004-01-01

    9 May 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a suite of frost-covered sand dunes in the north polar region of Mars in early spring, 2004. The dunes indicate wind transport of sand from left to right (west to east). These landforms are located near 78.1oN, 220.8oW. This picture is illuminated by sunlight from the lower left and covers an area about 3 km (1.9 mi) across.

  11. Corridors of barchan dunes: Stability and size selection

    DEFF Research Database (Denmark)

    Hersen, P.; Andersen, Ken Haste; Elbelrhiti, H.

    2004-01-01

    state. Second, the propagation speed of dunes decreases with the size of the dune: this leads, through the collision process, to a coarsening of barchan fields. We show that these phenomena are not specific to the model, but result from general and robust mechanisms. The length scales needed...... for these instabilities to develop are derived and discussed. They turn out to be much smaller than the dune field length. As a conclusion, there should exist further, yet unknown, mechanisms regulating and selecting the size of dunes....

  12. Hurricane Irma's Effects on Dune and Beach Morphology at Matanzas Inlet, Atlantic Coast of North Florida: Impacts and Inhibited Recovery?

    Science.gov (United States)

    Adams, P. N.; Conlin, M. P.; Johnson, H. A.; Paniagua-Arroyave, J. F.; Woo, H. B.; Kelly, B. P.

    2017-12-01

    During energetic coastal storms, surge from low atmospheric pressure, high wave set-up, and increased wave activity contribute to significant morphologic change within the dune and upper beach environments of barrier island systems. Hurricane Irma made landfall on the southwestern portion of the Florida peninsula, as a category 4 storm on Sept 10th, 2017 and tracked northward along the axis of the Florida peninsula for two days before dissipating over the North American continent. Observations along the North Florida Atlantic coast recorded significant wave heights of nearly 7 m and water levels that exceeded predictions by 2 meters on the early morning of Sept. 11th. At Fort Matanzas National Monument, the dune and upper beach adjacent to Matanzas Inlet experienced landward retreat during the storm, diminishing the acreage of dune and scrub habitat for federally-listed endangered and threatened animal species, including the Anastasia beach mouse, gopher tortoises, and several protected shore birds. Real Time Kinematic (RTK) GPS surveys, conducted prior to the passage of the storm (Sept. 8) and immediately after the storm (Sept. 13) document dune scarp retreat >10 m in places and an average retreat of 7.8 m (+/- 5.2 m) of the 2-m beach contour, attributable to the event, within the study region. Although it is typical to see sedimentary recovery at the base of dunes within weeks following an erosive event of this magnitude, our follow up RTK surveys, two weeks (Sept. 26) and five weeks (Oct. 19) after the storm, document continued dune retreat and upper beach lowering. Subsequent local buoy observations during the offshore passage of Hurricanes Jose, Maria (Sept. 17 and 23, respectively) and several early-season Nor'easters recorded wave heights well above normal (2-3 meters) from the northeast. The lack of recovery may reveal a threshold vulnerability of the system, in which the timing of multiple moderate-to-high wave events, in the aftermath of a land falling

  13. Matter Density Profile Shape Effects at DUNE

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Kevin J. [Northwestern U.; Parke, Stephen J. [Fermilab

    2018-02-19

    Quantum mechanical interactions between neutrinos and matter along the path of propagation, the Wolfenstein matter effect, are of particular importance for the upcoming long-baseline neutrino oscillation experiments, specifically the Deep Underground Neutrino Experiment (DUNE). Here, we explore specifically what about the matter density profile can be measured by DUNE, considering both the shape and normalization of the profile between the neutrinos' origin and detection. Additionally, we explore the capability of a perturbative method for calculating neutrino oscillation probabilities and whether this method is suitable for DUNE. We also briefly quantitatively explore the ability of DUNE to measure the Earth's matter density, and the impact of performing this measurement on measuring standard neutrino oscillation parameters.

  14. Assessing the impact of sea-level rise on a vulnerable coastal community in Accra, Ghana

    Directory of Open Access Journals (Sweden)

    Kwasi Appeaning Addo

    2013-08-01

    Full Text Available Climate change and its associated sea-level rise are expected to significantly affect vulnerable coastal communities. Although the extent of the impact will be localised, its assessment will adopt a monitoring approach that applies globally. The topography of the beach, the type of geological material and the level of human intervention will determine the extent of the area to be flooded and the rate at which the shoreline will move inland. Gleefe, a coastal community in Ghana, has experienced frequent flooding in recent times due to the increasing occurrence of storm surge and sea-level rise. This study used available geospatial data and field measurements to determine how the beach topography has contributed to the incidence of flooding at Gleefe. The topography is generally low-lying. Sections of the beach have elevations of around 1 m, which allows seawater to move inland during very high tide. Accelerated sea-level rise as predicted by the Intergovernmental Panel on Climate Change (IPCC will destroy homes of the inhabitants and inundate the Densu wetlands behind the beach. Destruction of infrastructure will render the inhabitants homeless, whilst flooding of the wetlands will destroy the habitats of migratory birds and some endangered wildlife species such as marine turtle. Effective adaptation measures should be adopted to protect this very important coastal environment, the ecology of the wetlands and the livelihoods of the community dwellers.

  15. Interactive network configuration maintains bacterioplankton community structure under elevated CO2 in a eutrophic coastal mesocosm experiment

    Science.gov (United States)

    Lin, Xin; Huang, Ruiping; Li, Yan; Li, Futian; Wu, Yaping; Hutchins, David A.; Dai, Minhan; Gao, Kunshan

    2018-01-01

    There is increasing concern about the effects of ocean acidification on marine biogeochemical and ecological processes and the organisms that drive them, including marine bacteria. Here, we examine the effects of elevated CO2 on the bacterioplankton community during a mesocosm experiment using an artificial phytoplankton community in subtropical, eutrophic coastal waters of Xiamen, southern China. Through sequencing the bacterial 16S rRNA gene V3-V4 region, we found that the bacterioplankton community in this high-nutrient coastal environment was relatively resilient to changes in seawater carbonate chemistry. Based on comparative ecological network analysis, we found that elevated CO2 hardly altered the network structure of high-abundance bacterioplankton taxa but appeared to reassemble the community network of low abundance taxa. This led to relatively high resilience of the whole bacterioplankton community to the elevated CO2 level and associated chemical changes. We also observed that the Flavobacteria group, which plays an important role in the microbial carbon pump, showed higher relative abundance under the elevated CO2 condition during the early stage of the phytoplankton bloom in the mesocosms. Our results provide new insights into how elevated CO2 may influence bacterioplankton community structure.

  16. Coral microbial communities, zooxanthellae and mucus along gradients of seawater depth and coastal pollution.

    Science.gov (United States)

    Klaus, James S; Janse, Ingmar; Heikoop, Jeffrey M; Sanford, Robert A; Fouke, Bruce W

    2007-05-01

    The high incidence of coral disease in shallow coastal marine environments suggests seawater depth and coastal pollution have an impact on the microbial communities inhabiting healthy coral tissues. A study was undertaken to determine how bacterial communities inhabiting tissues of the coral Montastraea annularis change at 5 m, 10 m and 20 m water depth in varying proximity to the urban centre and seaport of Willemstad, Curaçao, Netherlands Antilles. Analyses of terminal restriction fragment length polymorphisms (TRFLP) of 16S rRNA gene sequences show significant differences in bacterial communities of polluted and control localities only at the shallowest seawater depth. Furthermore, distinct differences in bacterial communities were found with increasing water depth. Comparisons of TRFLP peaks with sequenced clone libraries indicate the black band disease cyanobacterium clone CD1C11 is common and most abundant on healthy corals in less than 10 m water depth. Similarly, sequences belonging to a previously unrecognized group of likely phototrophic bacteria, herein referred to as CAB-I, were also more common in shallow water. To assess the influence of environmental and physiologic factors on bacterial community structure, canonical correspondence analysis was performed using explanatory variables associated with: (i) light availability; (ii) seawater pollution; (iii) coral mucus composition; (iv) the community structure of symbiotic algae; and (v) the photosynthetic activity of symbiotic algae. Eleven per cent of the variation in bacterial communities was accounted for by covariation with these variables; the most important being photosynthetically active radiation (sunlight) and the coral uptake of sewage-derived compounds as recorded by the delta(15)N of coral tissue.

  17. Dune-Yardang Interactions in Becquerel Crater, Mars

    Science.gov (United States)

    Urso, Anna; Chojnacki, Matthew; Vaz, David A.

    2018-02-01

    Isolated landscapes largely shaped by aeolian processes can occur on Earth, while the majority of Mars' recent history has been dominated by wind-driven activity. Resultantly, Martian landscapes often exhibit large-scale aeolian features, including yardang landforms carved from sedimentary-layered deposits. High-resolution orbital monitoring has revealed that persistent bedform activity is occurring with dune and ripple migration implying ongoing abrasion of the surface. However, little is known about the interaction between dunes and the topography surrounding them. Here we explore dune-yardang interactions in Becquerel crater in an effort to better understand local landscape evolution. Dunes there occur on the north and south sides of a 700 m tall sedimentary deposit, which displays numerous superposed yardangs. Dune and yardang orientations are congruent, suggesting that they both were formed under a predominantly northerly wind regime. Migration rates and sediment fluxes decrease as dunes approach the deposit and begin to increase again downwind of the deposit where the effect of topographic sheltering decreases. Estimated sand abrasion rates (16-40 μm yr-1) would yield a formation time of 1.8-4.5 Myr for the 70 m deep yardangs. This evidence for local aeolian abrasion also helps explain the young exposure ages of deposit surfaces, as estimated by the crater size-frequency distribution. Comparisons to terrestrial dune activity and yardang development begin to place constraints on yardang formation times for both Earth and Mars. These results provide insight into the complexities of sediment transport on uneven terrain and are compelling examples of contemporary aeolian-driven landscape evolution on Mars.

  18. Dune-Yardang Interactions in Becquerel Crater, Mars.

    Science.gov (United States)

    Urso, Anna; Chojnacki, Matthew; Vaz, David A

    2018-01-01

    Isolated landscapes largely shaped by aeolian processes can occur on Earth, while the majority of Mars' recent history has been dominated by wind-driven activity. Resultantly, Martian landscapes often exhibit large-scale aeolian features, including yardang landforms carved from sedimentary-layered deposits. High-resolution orbital monitoring has revealed that persistent bedform activity is occurring with dune and ripple migration implying ongoing abrasion of the surface. However, little is known about the interaction between dunes and the topography surrounding them. Here we explore dune-yardang interactions in Becquerel crater in an effort to better understand local landscape evolution. Dunes there occur on the north and south sides of a 700 m tall sedimentary deposit, which displays numerous superposed yardangs. Dune and yardang orientations are congruent, suggesting that they both were formed under a predominantly northerly wind regime. Migration rates and sediment fluxes decrease as dunes approach the deposit and begin to increase again downwind of the deposit where the effect of topographic sheltering decreases. Estimated sand abrasion rates (16-40 μm yr -1 ) would yield a formation time of 1.8-4.5 Myr for the 70 m deep yardangs. This evidence for local aeolian abrasion also helps explain the young exposure ages of deposit surfaces, as estimated by the crater size-frequency distribution. Comparisons to terrestrial dune activity and yardang development begin to place constraints on yardang formation times for both Earth and Mars. These results provide insight into the complexities of sediment transport on uneven terrain and are compelling examples of contemporary aeolian-driven landscape evolution on Mars.

  19. Large-eddy simulation of unidirectional turbulent flow over dunes

    Science.gov (United States)

    Omidyeganeh, Mohammad

    We performed large eddy simulation of the flow over a series of two- and three-dimensional dune geometries at laboratory scale using the Lagrangian dynamic eddy-viscosity subgrid-scale model. First, we studied the flow over a standard 2D transverse dune geometry, then bedform three-dimensionality was imposed. Finally, we investigated the turbulent flow over barchan dunes. The results are validated by comparison with simulations and experiments for the 2D dune case, while the results of the 3D dunes are validated qualitatively against experiments. The flow over transverse dunes separates at the dune crest, generating a shear layer that plays a crucial role in the transport of momentum and energy, as well as the generation of coherent structures. Spanwise vortices are generated in the separated shear; as they are advected, they undergo lateral instabilities and develop into horseshoe-like structures and finally reach the surface. The ejection that occurs between the legs of the vortex creates the upwelling and downdrafting events on the free surface known as "boils". The three-dimensional separation of flow at the crestline alters the distribution of wall pressure, which may cause secondary flow across the stream. The mean flow is characterized by a pair of counter-rotating streamwise vortices, with core radii of the order of the flow depth. Staggering the crestlines alters the secondary motion; two pairs of streamwise vortices appear (a strong one, centred about the lobe, and a weaker one, coming from the previous dune, centred around the saddle). The flow over barchan dunes presents significant differences to that over transverse dunes. The flow near the bed, upstream of the dune, diverges from the centerline plane; the flow close to the centerline plane separates at the crest and reattaches on the bed. Away from the centerline plane and along the horns, flow separation occurs intermittently. The flow in the separation bubble is routed towards the horns and leaves

  20. Nekton communities in Hawaiian coastal wetlands: The distribution and abundance of introduced fish species

    Science.gov (United States)

    Richard Ames MacKenzie; Gregory L. Bruland

    2012-01-01

    Nekton communities were sampled from 38 Hawaiian coastal wetlands from 2007 to 2009 using lift nets, seines, and throw nets in an attempt to increase our understanding of the nekton assemblages that utilize these poorly studied ecosystems. Nekton were dominated by exotic species, primarily poeciliids (Gambusia affinis, Poecilia...

  1. Deploying scanning lidars at coastal sites

    DEFF Research Database (Denmark)

    Courtney, Michael; Simon, Elliot

    that the most desirable sites are away from sand dunes and with some significant elevation above the sea surface, such as at the top of a cliff. Coastal planning restrictions in Denmark are quite restrictive and it was important to allow sufficient time to obtain permission from the relevant authorities....... At the same time, with our particular application, the authorities and land owners were quite favourably inclined to give permission to temporary installations in support of wind energy research. The report concludes with the final positions and a pictorial description of the three RUNE scanning lidars....

  2. Potential impacts of sea level rise on native plant communities and associated cultural sites in coastal areas of the main Hawaiian Islands

    Science.gov (United States)

    Jacobi, James D.; Warshauer, Frederick R.

    2017-01-01

    Hawaiian coastal vegetation is comprised of plant species that are adapted to growing in extremely harsh conditions (salt spray, wave wash, wind, and substrates with limited nutrients) found in this habitat zone. Prior to human colonization of Hawai‘i coastal vegetation extended as a continuous ring around each of the islands, broken only by stretches of recent lava flows or unstable cliff faces. However, since humans arrived in Hawai‘i many areas that originally supported native coastal plant communities have been highly altered or the native vegetation totally removed for agriculture, housing, or resort development, destroyed by fire, displaced by invasive plants, eaten by introduced mammals, or damaged by recreational use. This study was focused on identifying sites that still retain relatively intact and highly diverse native coastal plant communities throughout the main Hawaiian Islands that may be further impacted by projected sea level rise. Approximately 40 percent of Hawai‘i’s coastlines were found to still contain high quality native coastal plant communities. Most of these sites were located in areas where the coastal vegetation can still migrate inshore in response to rising sea level and associated inundation by waves. However, six sites with high-quality native coastal vegetation were found on low-lying offshore islets that will be totally inundated with a one meter increase in sea level and thirty sites were found to have some type of fixed barrier, such as a paved road or structure, which would restrict the plants from colonizing the adjacent inland areas. Many of these sites also have other cultural resources that are fixed in place and will definitely be impacted by rising sea level. The results of this study can help refine our understanding of Hawai‘i’s remaining native coastal vegetation and aid with the development of management and restoration strategies to ensure the long-term survival of these unique plant communities.

  3. Community Participation Of Coastal Area On Management Of National Park, Karimunjawa Island

    Science.gov (United States)

    Wibowo, Bambang A.; Aditomo, Aryo B.; Prihantoko, Kukuh E.

    2018-02-01

    Karimunjawa island located in Jepara Regacy, Central Java has potential marine and fishing resources. Since 1998, this area has been selected as conservation for its natural resources. National park of Karimunjawa is managed by Balai Taman Nasional Karimunjawa (Karimunjawa National Park Beuroue). Some activities involved community have been done in order to get effective management. Community participation is an important component for success in coastal area management. The level of community/people awareness anual on natural resource conservation can increate sustainable resource. However, it is necesssary to provide tools in resource utilization for the community, so that their economic life can be secured. This study observe the level of community participation in the effort of Karimunjawa National Park management. Descriptive method and purposive random sampling were used to carry out the study parameters observed in this study include community participation related to level of knowladge and obedience on the rule of area zonation, an its impact to community. The result show that community knowledge was quite high (40%) with obedience (56%) on the rule of area zonation. Impact area zonation rule was less significant to community. The level of community participation to Karimunjawa National Park management was performed will low to medium level.

  4. Formation of aeolian dunes on Anholt, Denmark since AD 1560

    DEFF Research Database (Denmark)

    Clemmensen, Lars B; Bjørnsen, Mette; Murray, Andrew

    2007-01-01

    Sand dunes on the island of Anholt (Denmark) in the middle of Kattegat form a relatively barren, temperate climate Aeolian system, locally termed the "Desert". The dunes have developed on top of a raised beach ridge system under the influence of dominant winds from westerly directions. They are r......Sand dunes on the island of Anholt (Denmark) in the middle of Kattegat form a relatively barren, temperate climate Aeolian system, locally termed the "Desert". The dunes have developed on top of a raised beach ridge system under the influence of dominant winds from westerly directions....... They are relatively coarse-grained with an average mean grain size of 480 µm. The last phase of aeolian activity and dune formation on Anholt started after AD 1560, when the local pine forest was removed. Historical sources report intense sand mobilization in the 17th century, and new optically stimulated...... in the beginning of the 20th century probably records a temporary decrease in storminess. Ground-penetrating radar mapping of the internal structures in two dunes in the western part of the Desert (a parabolic dune and a linear dune) indicates the importance of north-westerly (storm) winds during dune formation...

  5. UAV photogrammetry for topographic monitoring of coastal areas

    Science.gov (United States)

    Gonçalves, J. A.; Henriques, R.

    2015-06-01

    Coastal areas suffer degradation due to the action of the sea and other natural and human-induced causes. Topographical changes in beaches and sand dunes need to be assessed, both after severe events and on a regular basis, to build models that can predict the evolution of these natural environments. This is an important application for airborne LIDAR, and conventional photogrammetry is also being used for regular monitoring programs of sensitive coastal areas. This paper analyses the use of unmanned aerial vehicles (UAV) to map and monitor sand dunes and beaches. A very light plane (SwingletCam) equipped with a very cheap, non-metric camera was used to acquire images with ground resolutions better than 5 cm. The Agisoft Photoscan software was used to orientate the images, extract point clouds, build a digital surface model and produce orthoimage mosaics. The processing, which includes automatic aerial triangulation with camera calibration and subsequent model generation, was mostly automated. To achieve the best positional accuracy for the whole process, signalised ground control points were surveyed with a differential GPS receiver. Two very sensitive test areas on the Portuguese northwest coast were analysed. Detailed DSMs were obtained with 10 cm grid spacing and vertical accuracy (RMS) ranging from 3.5 to 5.0 cm, which is very similar to the image ground resolution (3.2-4.5 cm). Where possible to assess, the planimetric accuracy of the orthoimage mosaics was found to be subpixel. Within the regular coastal monitoring programme being carried out in the region, UAVs can replace many of the conventional flights, with considerable gains in the cost of the data acquisition and without any loss in the quality of topographic and aerial imagery data.

  6. Origin of the late quaternary dune fields of northeastern Colorado

    Science.gov (United States)

    Muhs, D.R.; Stafford, T.W.; Cowherd, S.D.; Mahan, S.A.; Kihl, R.; Maat, P.B.; Bush, C.A.; Nehring, J.

    1996-01-01

    Stabilized eolian deposits, mostly parabolic dunes and sand sheets, cover much of the landscape of northeastern Colorado and adjacent parts of southwestern Nebraska in four geographically distinct dune fields. Stratigraphic and soil-geomorphic relations and accelerator radiocarbon dating indicate that at least three episodes of eolian sand movement occurred between 27 ka and 11 ka, possibly between 11 ka and 4 ka, and within the past 1.5 ka. Thus, eolian sand deposition took place under both glacial and interglacial climatic conditions. In the youngest episodes of eolian sand movement, Holocene parabolic dunes partially buried Pleistocene sand sheet deposits. Late Holocene sands in the Fort Morgan and Wray dune fields, to the south of the South Platte River, have trace element ratios that are indistinguishable from modern South Platte River sands, but different from Ogallala Formation bedrock, which has previously been cited as the main source of dune sand on the Great Plains. Sands in the Greeley dune field, to the north of the South Platte River, have trace element concentrations that indicate a probable Laramie Formation source. Measurements of parabolic dunes indicate paleowinds from the northwest in all dune fields, in good agreement with resultant drift directions calculated for nearby weather stations. Thus, paleowinds were probably not significantly different from present-day winds, and are consistent with a South Platte River source for the Fort Morgan and Wray dune fields, and a Laramie Formation source for the Greeley dune field. Sand accumulated downwind of the South Platte River to form the Fort Morgan dune field. In addition, sand was also transported farther downwind over the upland formed by the calcrete caprock of the Ogallala Formation, and deposited in die lee of the upland on the southeast side. Because of high wind energy, the upland itself served as a zone of sand transport, but little or no sand accumulation took place on this surface. These

  7. Development of north sea coastal plankton communities in separate plastic bags under identical conditions

    NARCIS (Netherlands)

    Kuiper, J.

    1977-01-01

    In two experiments lasting 4 to 6 weeks, communities of North Sea coastal plankton kept in separate plastic bags (of about 1400 l) and exposed to the same environmental conditions showed very similar patterns of growth and decline. This result means that the method is suitable for the evaluation of

  8. Development and Application of Percent Annual Chance Coastal Inundation Maps to Support Decision-Making in the Northern Gulf of Mexico

    Science.gov (United States)

    Bilskie, M. V.; Hagen, S. C.; Irish, J. L.; Yoskowitz, D.; Del Angel, D. C.

    2017-12-01

    Rising sea levels increase the vulnerability, exposure, probability, and thus risk associated with hurricane storm surge flooding across low-gradient coastal landscapes. In the U.S., flood risk assessments commonly employ the delineation of the 1% annual chance flood (100-year return period) that guide coastal policy and planning. As many coastal communities now include climate change effects on future development activities, the need to provide scientifically sound and scenario-based data products are becoming increasingly essential. Implementing bio-geo-physical models to study the effects of sea level rise (SLR) on coastal flooding under a variety of scenarios can be a powerful tool. However, model results alone are not appropriate for use by the broader coastal management community and thus must be further refined. For example, developing return period inundations maps or examining the potential economic damages are vital to translate scientific finding and extend their practicality to coastal resources managers, stakeholders, and governmental agencies. This work employs a collection of high-resolution wind-wave and hurricane storm surge models forced by a suite of synthetic storms to derive the 1% and 0.2% annual chance floodplain under four SLR scenarios (0.2, m, 0.5 m, 1.2 m, and 2.0 m) across the northern Gulf of Mexico (NGOM) coast, which include Mississippi, Alabama, and the Florida panhandle. The models represent the potential outlook of the coastal landscape for each of the scenarios and contains changes to the salt marsh, barrier islands, shoreline position, dune elevations, and land use land cover. Simulated surge data are fed into a hazard assessment tool that provides estimates of potential future damages and costs for each SLR scenario. Results provide evidence that the present 500-year floodplain becomes the 100-year floodplain under the 0.5 m SLR scenario by the end of the century along the Alabama and the Florida panhandle coast. Across

  9. High Arctic Coasts At Risk - The Impact of Coastal Hazards on Scientific and Community Infrastructure in Svalbard

    Science.gov (United States)

    Strzelecki, M. C.; Pawlowski, L.; Jaskolski, M.; Lim, M.; Zagorski, P.; Long, A. J.; Jensen, M.

    2015-12-01

    The rapid climate warming being observed in the Svalbard is leading to an increase in human activities in the coastal zone, leading to an increased need for coastal hazard assessment. Present-day Svalbard coastal landscapes are modified by increased degradation of permafrost accelerated sediment supply from deglaciated catchments, and prolonged periods of open-water conditions and wave activity. Since the second half of 20thcentury there is also an observed increase in the number and intensity of storms entering the Arctic particularly in summer months when coastlines are free of protective ice cover. Despite the potential significance of these coastal hazards on the security of scientific (research bases and devices) and community (ports, airports, roads, buildings) infrastructure on Svalbard, relatively little is known on the present-day rate of Svalbard coastal zone changes and how they might impact the nearshore infrastructure in the future. Here we report the results of a project that focused on rates of coastal zone changes in Svalbard and examined the impact of extreme coastal processes on scientific and community infrastructure. The project applied combination of remote sensing and field-based mapping techniques to characterise coastal changes observed in the surroundings of main research stations in Svalbard in Hornsund (PPS), Petuniabukta (AMUPS) and Bellsund (Calypsobyen) as well as a major towns: Longyearbyen, Piramiden, Barentsburg and Svea. Our results document dramatic changes of Svalbard coastal zone under intervals characterised by a warming climate, retreating local ice masses, a shortened winter sea-ice season and melting permafrost. The study confirmed the growing importance of extreme processes in shaping coasts of Svalbard and the impact of these changes on human infrastructure. Our study proposes a risk assessment for a development and protection of infrastructure along the coasts of Svalbard under scenarios of climate change, sea level rise

  10. Coastal Mapping for Baseline Geoscience Knowledge to Support Community Hazard Assessment and Sustainable Development, Eastern Baffin Island, Nunavut

    Science.gov (United States)

    Forbes, D. L.; Bell, T.; Campbell, D. C.; Cowan, B.; Deering, R. L.; Hatcher, S. V.; Hughes Clarke, J. E.; Irvine, M.; Manson, G. K.; Smith, I. R.; Edinger, E.

    2015-12-01

    Since 2012 we have carried out extensive multibeam bathymetric and backscatter surveys in coastal waters of eastern Baffin Island, supplemented by sub-bottom imaging and coring. Shore-zone surveys have been undertaken in proximity to the communities of Iqaluit and Qikiqtarjuaq, following earlier work in Clyde River. These support benthic habitat mapping, geological exploration, analysis of past and present sea-level trends, and assessment of coastal hazards relating to climate change and seabed instability. Outputs include a seamless topographic-bathymetric digital elevation model (DEM) of extensive boulder-strewn tidal flats in the large tidal-range setting at Iqaluit, supporting analysis of coastal flooding, wave run-up, and sea-ice impacts on a rapidly developing urban waterfront in the context of climate change. Seabed mapping of inner Frobisher Bay seaward of Iqaluit reveals a potential local tsunami hazard in widespread submarine slope failures, the triggers, magnitudes, and ages of which are the subject of ongoing research. In fjords of the Cumberland Peninsula, this project has mapped numerous submerged delta terraces at 19 to 45 m present water depth. These attest to an early postglacial submerged shoreline, displaced by glacial-isostatic adjustment. It rises linearly over a distance of 100 km east to west, where a submerged boulder barricade on a -16 m shoreline was discovered at a proposed port site in Broughton Channel near Qikiqtarjuaq. Palaeotopographic mapping using the multibeam data revealed an enclosed estuarine environment quite different from the present-day open passage swept by tidal currents. At Clyde River, combined seabed and onshore DEMs with geohazard mapping provided foundation data for community assessment and planning under a local knowledge co-production initiative. The geohazard work identified portions of the town-site more vulnerable to both coastal flooding and potential thaw subsidence, while the shallow delta terrace suggested a

  11. Do recreational activities affect coastal biodiversity?

    Science.gov (United States)

    Riera, Rodrigo; Menci, Cristiano; Sanabria-Fernández, José Antonio; Becerro, Mikel A.

    2016-09-01

    Human activities are largely affecting coastal communities worldwide. Recreational perturbations have been overlooked in comparison to other perturbations, yet they are potential threats to marine biodiversity. They affect coastal communities in different ways, underpinning consistent shifts in fish and invertebrates assemblages. Several sites were sampled subjected to varying effects by recreational fishermen (low and high pressure) and scuba divers (low and high) in an overpopulated Atlantic island. Non-consistent differences in ecological, trophic and functional diversity were found in coastal communities, considering both factors (;diving; and ;fishing;). Multivariate analyses only showed significant differences in benthic invertebrates between intensively-dived and non-dived sites. The lack of clear trends may be explained by the depletion of coastal resources in the study area, an extensively-affected island by overfishing.

  12. Preliminary assessment of coastal erosion and local community adaptation in Sayung coastal area, central Java – Indonesia

    OpenAIRE

    Marfai, Muh Aris

    2012-01-01

    Dynamic environment in coastal area, especially due to coastal erosion process, has negative impact on human environment. Sayung coastal area, located in Central Java-Indonesia, has experienced severe impact of coastal erosion. As the result of the coastal erosion, hundreds of settlement located in coastal area has been destructed. Moreover, fishponds as the land use dominated in the coastal area also has been severely destroyed. Besides the coastal erosion, increasing of inundated area due t...

  13. Coastal zones : shifting shores, sharing adaptation strategies for coastal environments

    Energy Technology Data Exchange (ETDEWEB)

    Hay, J.E. [Waikato Univ. (New Zealand); Morneau, F.; Savard, J.P. [Ouranos, Montreal, PQ (Canada); Madruga, R.P. [Centre of Investigation on the Global Economy (Cuba); Leslie, K.R. [Caribbean Community Climate Change Centre (Belize); Agricole, W. [Ministry of Environment and Natural Resources (Seychelles); Burkett, V. [United States Geological Survey (United States)

    2006-07-01

    A parallel event to the eleventh Conference of Parties (COP) to the United Nations Framework Convention of Climate Change was held to demonstrate examples of adaptation from around the world in the areas of food security, water resources, coastal zones, and communities/infrastructure. Panels on each theme presented examples from developing countries, countries in economic transition, and developed countries. These 4 themes were chosen because both mitigation and adaptation are essential to meeting the challenge of climate change. The objective of the event was to improve the knowledge of Canada's vulnerabilities to climate change, identify ways to minimize the negative effects of future impacts, and explore opportunities that take advantage of any positive impacts. This third session focused on how coastal communities are adapting to climate change in such places as Quebec, the Caribbean, and small Island States. It also presented the example of how a developed country became vulnerable to Hurricane Katrina which hit the coastal zone in the United States Gulf of Mexico. The presentations addressed the challenges facing coastal communities along with progress in risk assessment and adaptation both globally and in the Pacific. Examples of coastal erosion in Quebec resulting from climate change were presented along with climate change and variability impacts over the coastal zones of Seychelles. Cuba's vulnerability and adaptation to climate change was discussed together with an integrated operational approach to climate change, adaptation, biodiversity and land utilization in the Caribbean region. The lessons learned from around the world emphasize that adaptation is needed to reduce unavoidable risks posed by climate change and to better prepare for the changes ahead. refs., tabs., figs.

  14. Coexistence of Dunes and Humid Conditions at Titan's Tropics

    Science.gov (United States)

    Radebaugh, Jani; Lorenz, R. D.; Lunine, J. I.; Kirk, R. L.; Ori, G. G.; Farr, T. G.; Malaska, M.; Le Gall, A.; Liu, Z. Y. C.; Encrenaz, P. J.; Paillou, P.; Hayes, A.; Lopes, R. M. C.; Turtle, E. P.; Wall, S. D.; Stofan, E. R.; Wood, C. A.; Cassini RADAR Team

    2012-10-01

    At Titan's equatorial latitudes there are tens of thousands of dunes, a landform typical of desert environments where sand does not become anchored by vegetation or fluids. Model climate simulations predict generally dry conditions at the equator and humid conditions near the poles of Titan, where lakes of methane/ethane are found. However, moderate relative methane humidity was observed at the Huygens landing site, recent rainfall was seen by Cassini ISS near the Belet Sand Sea, and a putative transient lake in Shangri-La was observed by Cassini VIMS, all of which indicate abundant fluids may be present, at least periodically, at Titan's equatorial latitudes. Terrestrial observations and studies demonstrate dunes can exist and migrate in conditions of high humidity. Active dunes are found in humid climates, indicating the movement of sand is not always prohibited by the presence of fluids. Sand mobility is related to precipitation, evaporation and wind speed and direction. If dune surfaces become wetted by rainfall or rising subsurface fluids, they can become immobilized. However, winds can act to dry the uppermost layers, freeing sands for saltation and enabling dune migration in wet conditions. Active dunes are found in tropical NE Brazil and NE Australia, where there are alternating dry and wet periods, a condition possible for Titan's tropics. Rising and falling water levels lead to the alteration of dune forms, mainly from being anchored by vegetation, but also from cementation by carbonates or clays. Studies of Titan's dunes, which could undergo anchoring of organic sediments by hydrocarbon fluids, could inform the relative strength of vegetation vs. cementation at humid dune regions on Earth. Furthermore, a comprehensive survey of dune morphologies near regions deemed low by SARTopo and stereo, where liquids may collect in wet conditions, could reveal if bodies of liquid have recently existed at Titan's tropics.

  15. Estimation of sand dune thickness using a vertical velocity profile

    International Nuclear Information System (INIS)

    Al-Shuhail, Abdullatif A.

    2004-01-01

    Previous field and mathematical studies have shown that sand dunes may have vertical velocity profiles (i.e. continuous increase of velocity with depth). Therefore, computing the dunes thickness using conventional seismic refraction methods that assume a vertically homogeneous layer will likely produce some errors. The purpose of this study is to quantify the effect of the vertical velocity profile in a sand dune on the process of thickness estimation using seismic refraction data. First, the time distance (T-X) data of the direct wave in the dune is calculated using a vertical velocity profile, V (z), derived from Hertz-Mindlin contact theory. Then the thickness is estimated from the calculated T-X data, intercept time and velocity of the refractor at the dune's base assuming a constant velocity in the dune. The error in the estimated thickness due to the constant-velocity assumption increases with increasing thickness and decreasing porosity of the dune. For sand dunes with porosities greater than 0.2 and thickness less than 200 meter, the error is less than 15%. (author)

  16. Episodic Late Holocene dune movements on the sand-sheet area, Great Sand Dunes National Park and Preserve, San Luis Valley, Colorado, USA

    Science.gov (United States)

    Forman, S. L.; Spaeth, M.; Marín, L.; Pierson, J.; Gómez, J.; Bunch, F.; Valdez, A.

    2006-07-01

    The Great Sand Dunes National Park and Preserve (GSDNPP) in the San Luis Valley, Colorado, contains a variety of eolian landforms that reflect Holocene drought variability. The most spectacular is a dune mass banked against the Sangre de Cristo Mountains, which is fronted by an extensive sand sheet with stabilized parabolic dunes. Stratigraphic exposures of parabolic dunes and associated luminescence dating of quartz grains by single-aliquot regeneration (SAR) protocols indicate eolian deposition of unknown magnitude occurred ca. 1290-940, 715 ± 80, 320 ± 30, and 200-120 yr ago and in the 20th century. There are 11 drought intervals inferred from the tree-ring record in the past 1300 yr at GSDNPP potentially associated with dune movement, though only five eolian depositional events are currently recognized in the stratigraphic record. There is evidence for eolian transport associated with dune movement in the 13th century, which may coincide with the "Great Drought", a 26-yr-long dry interval identified in the tree ring record, and associated with migration of Anasazi people from the Four Corners areas to wetter areas in southern New Mexico. This nascent chronology indicates that the transport of eolian sand across San Luis Valley was episodic in the late Holocene with appreciable dune migration in the 8th, 10-13th, and 19th centuries, which ultimately nourished the dune mass against the Sangre de Cristo Mountains.

  17. Modelling coastal processes and morphological changes of the UK east coast in support of coastal decision-making

    Science.gov (United States)

    Li, Xiaorong; Leonardi, Nicoletta; Brown, Jennifer; Plater, Andy

    2017-04-01

    The coastline of Eastern England is home to about one quarter of the UK's coastal habitats, including intertidal salt marshes, tidal flats and sand dunes. These geomorphic features are of great importance to the local wildlife, global biodiversity, marine environment and human society and economy. Due to sea-level rise and the occurrence of extreme weather conditions, the coastline of Eastern England is under high risk of erosion and recession, which could lead to tidal inundation of sites such as the RSPB Minsmere Reserve and power generation infrastructure at Sizewell. This research responds to the need for sustainable shoreline management plans of the UK east coast through sensitivity studies at the Dunwich-Sizewell area, Suffolk, UK. Particular interest is on the long-term morphodynamic response of the study area to possible environmental variations associated with global climate change. Key coastal processes, i.e. current, waves and sediment transport, and morphological evolution are studied using a process-based numerical model under the following scenarios: current mean sea level + calm wave conditions, current mean sea level + storms, sea level rise + calm wave conditions, and sea level rise + storms, all with a 'do nothing' management plan which allows the coastal environment to exist and respond dynamically. As a further aspect of this research, rules will be generalized for reduced-complexity, system-based modelling. Alternative management plans, including 'managed realignment' and 'advance the line', are also investigated in this research under the same environmental forcing scenarios, for the purposes of protection of infrastructure of national importance and conservation of wetland habitats. Both 'hard' and 'soft' engineering options, such as groynes and beach nourishment respectively, are considered. A more ecohydrological option which utilizes aquatic plant communities for wave energy dissipation and sediment trapping is also studied. The last

  18. Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE): Conceptual Design Report. Volume 3: Long-Baseline Neutrino Facility for DUNE

    Energy Technology Data Exchange (ETDEWEB)

    Strait, James [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); McCluskey, Elaine [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Lundin, Tracy [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Willhite, Joshua [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Hamernik, Thomas [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Papadimitriou, Vaia [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Marchionni, Alberto [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Kim, Min Jeong [National Inst. of Nuclear Physics (INFN), Frascati (Italy). National Lab. of Frascati (INFN-LNF); Nessi, Marzio [Univ. of Geneva (Switzerland); Montanari, David [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Heavey, Anne [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)

    2016-01-21

    This volume of the LBNF/DUNE Conceptual Design Report covers the Long-Baseline Neutrino Facility for DUNE and describes the LBNF Project, which includes design and construction of the beamline at Fermilab, the conventional facilities at both Fermilab and SURF, and the cryostat and cryogenics infrastructure required for the DUNE far detector.

  19. Large-eddy simulation of sand dune morphodynamics

    Science.gov (United States)

    Khosronejad, Ali; Sotiropoulos, Fotis; St. Anthony Falls Laboratory, University of Minnesota Team

    2015-11-01

    Sand dunes are natural features that form under complex interaction between turbulent flow and bed morphodynamics. We employ a fully-coupled 3D numerical model (Khosronejad and Sotiropoulos, 2014, Journal of Fluid Mechanics, 753:150-216) to perform high-resolution large-eddy simulations of turbulence and bed morphodynamics in a laboratory scale mobile-bed channel to investigate initiation, evolution and quasi-equilibrium of sand dunes (Venditti and Church, 2005, J. Geophysical Research, 110:F01009). We employ a curvilinear immersed boundary method along with convection-diffusion and bed-morphodynamics modules to simulate the suspended sediment and the bed-load transports respectively. The coupled simulation were carried out on a grid with more than 100 million grid nodes and simulated about 3 hours of physical time of dune evolution. The simulations provide the first complete description of sand dune formation and long-term evolution. The geometric characteristics of the simulated dunes are shown to be in excellent agreement with observed data obtained across a broad range of scales. This work was supported by NSF Grants EAR-0120914 (as part of the National Center for Earth-Surface Dynamics). Computational resources were provided by the University of Minnesota Supercomputing Institute.

  20. Discrimination of coastal wetland environments in the Amazon region based on multi-polarized L-band airborne Synthetic Aperture Radar imagery

    Science.gov (United States)

    Souza-Filho, Pedro Walfir M.; Paradella, Waldir R.; Rodrigues, Suzan W. P.; Costa, Francisco R.; Mura, José C.; Gonçalves, Fabrício D.

    2011-11-01

    This study assessed the use of multi-polarized L-band images for the identification of coastal wetland environments in the Amazon coast region of northern Brazil. Data were acquired with a SAR R99B sensor from the Amazon Surveillance System (SIVAM) on board a Brazilian Air Force jet. Flights took place in the framework of the 2005 MAPSAR simulation campaign, a German-Brazilian feasibility study focusing on a L-band SAR satellite. Information retrieval was based on the recognition of the interaction between a radar signal and shallow-water morphology in intertidal areas, coastal dunes, mangroves, marshes and the coastal plateau. Regarding the performance of polarizations, VV was superior for recognizing intertidal area morphology under low spring tide conditions; HH for mapping coastal environments covered with forest and scrub vegetation such as mangrove and vegetated dunes, and HV was suitable for distinguishing transition zones between mangroves and coastal plateau. The statistical results for the classification maps expressed by kappa index and general accuracy were 83.3% and 0.734 for the multi-polarized color composition (R-HH, G-HV, B-VV), 80.7% and 0.694% for HH, 79.7% and 0.673% for VV, and 77.9% and 0.645% for HV amplitude image. The results indicate that use of multi-polarized L-band SAR is a valuable source of information aiming at the identification and discrimination of distinct geomorphic targets in tropical wetlands.

  1. Phylogenetic comparisons of a coastal bacterioplankton community with its counterparts in open ocean and freshwater systems.

    Science.gov (United States)

    Rappé; Vergin; Giovannoni

    2000-09-01

    In order to extend previous comparisons between coastal marine bacterioplankton communities and their open ocean and freshwater counterparts, here we summarize and provide new data on a clone library of 105 SSU rRNA genes recovered from seawater collected over the western continental shelf of the USA in the Pacific Ocean. Comparisons to previously published data revealed that this coastal bacterioplankton clone library was dominated by SSU rRNA gene phylotypes originally described from surface waters of the open ocean, but also revealed unique SSU rRNA gene lineages of beta Proteobacteria related to those found in clone libraries from freshwater habitats. beta Proteobacteria lineages common to coastal and freshwater samples included members of a clade of obligately methylotrophic bacteria, SSU rRNA genes affiliated with Xylophilus ampelinus, and a clade related to the genus Duganella. In addition, SSU rRNA genes were recovered from such previously recognized marine bacterioplankton SSU rRNA gene clone clusters as the SAR86, SAR11, and SAR116 clusters within the class Proteobacteria, the Roseobacter clade of the alpha subclass of the Proteobacteria, the marine group A/SAR406 cluster, and the marine Actinobacteria clade. Overall, these results support and extend previous observations concerning the global distribution of several marine planktonic prokaryote SSU rRNA gene phylotypes, but also show that coastal bacterioplankton communities contain SSU rRNA gene lineages (and presumably bacterioplankton) shown previously to be prevalent in freshwater habitats.

  2. Physical and economic impacts of sea-level rise and low probability flooding events on coastal communities.

    Directory of Open Access Journals (Sweden)

    Thomas Prime

    Full Text Available Conventionally flood mapping typically includes only a static water level (e.g. peak of a storm tide in coastal flood inundation events. Additional factors become increasingly important when increased water-level thresholds are met during the combination of a storm tide and increased mean sea level. This research incorporates factors such as wave overtopping and river flow in a range of flood inundation scenarios of future sea-level projections for a UK case study of Fleetwood, northwest England. With increasing mean sea level it is shown that wave overtopping and river forcing have an important bearing on the cost of coastal flood events. The method presented converts inundation maps into monetary cost. This research demonstrates that under scenarios of joint extreme surge-wave-river events the cost of flooding can be increased by up to a factor of 8 compared with an increase in extent of up to a factor of 3 relative to "surge alone" event. This is due to different areas being exposed to different flood hazards and areas with common hazard where flood waters combine non-linearly. This shows that relying simply on flood extent and volume can under-predict the actual economic impact felt by a coastal community. Additionally, the scenario inundation depths have been presented as "brick course" maps, which represent a new way of interpreting flood maps. This is primarily aimed at stakeholders to increase levels of engagement within the coastal community.

  3. Physical and economic impacts of sea-level rise and low probability flooding events on coastal communities.

    Science.gov (United States)

    Prime, Thomas; Brown, Jennifer M; Plater, Andrew J

    2015-01-01

    Conventionally flood mapping typically includes only a static water level (e.g. peak of a storm tide) in coastal flood inundation events. Additional factors become increasingly important when increased water-level thresholds are met during the combination of a storm tide and increased mean sea level. This research incorporates factors such as wave overtopping and river flow in a range of flood inundation scenarios of future sea-level projections for a UK case study of Fleetwood, northwest England. With increasing mean sea level it is shown that wave overtopping and river forcing have an important bearing on the cost of coastal flood events. The method presented converts inundation maps into monetary cost. This research demonstrates that under scenarios of joint extreme surge-wave-river events the cost of flooding can be increased by up to a factor of 8 compared with an increase in extent of up to a factor of 3 relative to "surge alone" event. This is due to different areas being exposed to different flood hazards and areas with common hazard where flood waters combine non-linearly. This shows that relying simply on flood extent and volume can under-predict the actual economic impact felt by a coastal community. Additionally, the scenario inundation depths have been presented as "brick course" maps, which represent a new way of interpreting flood maps. This is primarily aimed at stakeholders to increase levels of engagement within the coastal community.

  4. DETECTION OF BARCHAN DUNES IN HIGH RESOLUTION SATELLITE IMAGES

    Directory of Open Access Journals (Sweden)

    M. A. Azzaoui

    2016-06-01

    Full Text Available Barchan dunes are the fastest moving sand dunes in the desert. We developed a process to detect barchans dunes on High resolution satellite images. It consisted of three steps, we first enhanced the image using histogram equalization and noise reduction filters. Then, the second step proceeds to eliminate the parts of the image having a texture different from that of the barchans dunes. Using supervised learning, we tested a coarse to fine textural analysis based on Kolomogorov Smirnov test and Youden’s J-statistic on co-occurrence matrix. As an output we obtained a mask that we used in the next step to reduce the search area. In the third step we used a gliding window on the mask and check SURF features with SVM to get barchans dunes candidates. Detected barchans dunes were considered as the fusion of overlapping candidates. The results of this approach were very satisfying in processing time and precision.

  5. Mosquito fauna and arbovirus surveillance in a coastal Mississippi community after Hurricane Katrina.

    Science.gov (United States)

    Foppa, Ivo M; Evans, Christopher L; Wozniak, Arthur; Wills, William

    2007-06-01

    Hurricane Katrina caused massive destruction and flooding along the Gulf Coast in August 2005. We collected mosquitoes and tested them for arboviral infection in a severely hurricane-damaged community to determine species composition and to assess the risk of a mosquito-borne epidemic disease in that community about 6 wk after the landfall of Hurricane Katrina. Light-trap collections yielded 8,215 mosquitoes representing 19 species, while limited gravid-trap collections were not productive. The most abundant mosquito species was Culex nigripalpus, which constituted 73.6% of all specimens. No arboviruses were detected in any of the mosquitoes collected in this survey, which did not support the assertion that human risk for arboviral infection was increased in the coastal community 6 wk after the hurricane.

  6. Frost-free Dunes

    Science.gov (United States)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA03291 Frost-free Dunes These dark dunes are frost covered for most of the year. As southern summer draws to a close, the dunes have been completely defrosted. Image information: VIS instrument. Latitude -66.6N, Longitude 37.0E. 34 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  7. Coastal vulnerability index for the Tabasco State coast, Mexico

    Directory of Open Access Journals (Sweden)

    Juan Carlos Nuñez Gómez

    2016-11-01

    Full Text Available Sea level rise is one of the most serious events that will impact low-lying lands, as is the case of most of Tabasco State. Historically, the State of Tabasco has been repeatedly impacted by extreme floods, the most recent one occurring in 2007. However, recent studies have shown that coastal erosion is the effect that most directly has impacted the Tabasco’s coastline, as this has even modified soil strata; this is also related to extreme hydrometeorological events associated with environmental changes and changes in the salinity gradient off the coast. In such a situation, future changes in the coastline are almost certain. Tabasco’s coastline has been recognized as one of the most vulnerable zones in the country since Mexico’s first national communication to the UNFCCC in 1997. Therefore, it is important to evaluate the vulnerability of this zone. The purpose of this study was to estimate the vulnerability of the Tabasco’s coastline by applying the coastal vulnerability index method (IVM using a geographic information system (GIS. This method has been successfully applied in several different places around the world including Canada, the United State, Spain and Indonesia. This model is suitable for the local conditions of Tabasco coast, as the input variables it requires (including waves, tides, sea level, coastal slope, erosion rates and geomorphology are available for the study area, thus allowing the possibility of estimating the coast’s vulnerability based on local data. Results from map algebra operations showed that the zones of very high or high vulnerability encompass a six-kilometer stretch around the Sánchez Magallanes community, near the del Carmen lagoon in the municipality of H. Cárdenas, Tabasco. This is due to the high-waves regime and other conditions associated to the coastal dune geomorphology as well as the unconsolidated fine sediments prevailing therein. Other high vulnerability zones are found just in front

  8. Inventory of coastal protected areas and historical heritage sites (North Bulgarian coast)

    Science.gov (United States)

    Palazov, Atanas; Stancheva, Margarita; Stanchev, Hristo; Krastev, Anton; Peev, Preslav

    2015-04-01

    Coastal protected areas and historical heritage sites in Bulgaria are established by national policy instruments/laws and EU Directives to protect a wide range of natural and cultural resources along the coast. Within the framework of HERAS Project (Submarine Archaeological Heritage of the Western Black Sea Shelf), financed by European Union under the CBC Program Romania-Bulgaria, we made an inventory and identification of protected areas, nature reserves, monuments, parks and onshore historical sites along the North Bulgarian coast (NUTS III level). The adjacent coastline is 96 km long between cape Sivriburun to the border of Romania on the north and cape Ekrene on the south. Coastal zone here is mostly undeveloped and low urbanized compared to other coastal regions in Bulgaria. It comprises of large sand beaches, vast sand dunes, up to 70 m spectacular high limestone cliffs, coastal fresh-water lakes, wetlands etc. This coastal section includes also one of the most important wetlands and it is migration corridor for many protected birds in Bulgaria, that host one of the rarest ecosystem types with national and international conservational value. Added to ecosystem values, the region is also an archeologically important area, where numerous underwater and coastal archaeological sites from different periods have been discovered - Prehistory, Antiquity (ancient Greek, Hellenistic, Roman), Mediaeval (Early Byzantium, Bulgarian). Research was made within 2100 m zone from the coastline (in accordance with zones defined by the Black Sea Coastal Development Act) for territories with protected status in the framework of many national laws and EU Directives. The total area of this strip zone is 182, 6 km2 and around 67% is under protection. There are 11 unique NATURA 2000 protected areas (6 Special Protection Areas (SPAs) and 5 Sites of Communities Importance (SCI), 2 nature reserves and 1 Nature Park. Some of them are also onshore historical sites. In Bulgaria such sites

  9. Disturbance drives phylogenetic community structure in coastal dune vegetation

    DEFF Research Database (Denmark)

    Brunbjerg, A.K.; Borchsenius, Finn; Eiserhardt, Wolf L.

    2012-01-01

    theories hereunder assign varying importance to dispersal limitation and local environmental species sorting. At present the relative importance of these factors across habitats, geographic regions, and spatial scales remains unclear. The present study assessed the relative importance of species sorting...

  10. Bacterial interactions in the rhizosphere of seagrass communities in shallow coastal lagoons.

    Science.gov (United States)

    Donnelly, A P; Herbert, R A

    1998-12-01

    Rooted phanerogam communities in the shallow intertidal and subtidal coastal zone represent productive and healthy ecosystems. Inorganic nutrients are assimilated into seagrass biomass. Much of the organic matter resulting from moribund seagrass is rapidly mineralized, principally by bacteria. The microbial community of the rhizosphere is also highly active due to the supply of organic matter released during photosynthesis. This active sediment community plays an important role through carbon, nitrogen and phosphorous cycling in maintaining the stability and productivity of seagrass meadows. Over the last two decades, however, seagrass meadows in European coastal areas have declined due to increasing pollution. As eutrophication advances a trasition occurs from rooted phanerogram dominated communities to planktonic algal blooms and/or cyanobacterial blooms. Such changes represent the decline of a stable, high biodiversity habitat to an unstable one dominated by a few species. These changes of community structure can occur rapidly once the internal nutrient and organic matter control cycles are exceeded. A field investigation was undertaken to establish the spatial distribution of bacterial populations of Zostera noltii colonized and uncolonized sediment in the Bassin d'Arcachon, France. Bacteria were enumerated using both plate count and MPN techniques for different functional groups as well as determining the total bacterial populations present. Nitrogen fixation, ammonification, sulphate reduction rates, as well as alkaline phosphatase activity were also determined. Colonization of the Z. noltii roots and rhizomes was studied by light and scanning electron microscopy. Results confirmed that higher bacterial populations were present in the rhizosphere of Z. noltii compared to uncolonized sediments. Furthermore, electron microscopy identified the rhizome as the main site of colonization for a diverse range of morphological groups of bacteria. Sulphate reducing

  11. Erosion and its rate on an accumulative Polish dune coast: the effects of the January 2012 storm surge

    OpenAIRE

    Łabuz, Tomasz A.

    2014-01-01

    The Polish coast is a non-tidal area; its shores are affected mainly by autumn-winter storm surges. Those of 6 and 14 January 2012 are representative of the forces driving the erosion of normally accumulative sections of coastal dunes, monitored by the author since 1997. The sea level maximum during these two storm surges reached 1.2 to 1.5 m amsl along the Polish coast. Land forms up to 3 m amsl were inundated. Beaches and low parts of the coast up to this height were rebuilt by sea waves at...

  12. Measurements of Dune Parameters on Titan Suggest Differences in Sand Availability

    Science.gov (United States)

    Stewart, Brigitte W.; Radebaugh, Jani

    2014-11-01

    The equatorial region of Saturn’s moon Titan has five large sand seas with dunes similar to large linear dunes on Earth. Cassini Radar SAR swaths have high enough resolution (300 m) to measure dune parameters such as width and spacing, which helps inform us about formation conditions and long-term evolution of the sand dunes. Previous measurements in locations scattered across Titan have revealed an average width of 1.3 km and spacing of 2.7 km, with variations by location. We have taken over 1200 new measurements of dune width and spacing in the T8 swath, a region on the leading hemisphere of Titan in the Belet Sand Sea, between -5 and -9 degrees latitude. We have also taken over 500 measurements in the T44 swath, located on the anti-Saturn hemisphere in the Shangri-La Sand Sea, between 0 and 20 degrees latitude. We correlated each group of 50 measurements with the average distance from the edge of the dune field to obtain an estimate of how position within a dune field affects dune parameters. We found that in general, the width and spacing of dunes decreases with distance from the edge of the dune field, consistent with similar measurements in sand seas on Earth. We suggest that this correlation is due to the lesser availability of sand at the edges of dune fields. These measurements and correlations could be helpful in determining differences in sand availability across different dune fields, and along the entire equatorial region of Titan.

  13. Probabilistic estimation of dune retreat on the Gold Coast, Australia

    Science.gov (United States)

    Palmsten, Margaret L.; Splinter, Kristen D.; Plant, Nathaniel G.; Stockdon, Hilary F.

    2014-01-01

    Sand dunes are an important natural buffer between storm impacts and development backing the beach on the Gold Coast of Queensland, Australia. The ability to forecast dune erosion at a prediction horizon of days to a week would allow efficient and timely response to dune erosion in this highly populated area. Towards this goal, we modified an existing probabilistic dune erosion model for use on the Gold Coast. The original model was trained using observations of dune response from Hurricane Ivan on Santa Rosa Island, Florida, USA (Plant and Stockdon 2012. Probabilistic prediction of barrier-island response to hurricanes, Journal of Geophysical Research, 117(F3), F03015). The model relates dune position change to pre-storm dune elevations, dune widths, and beach widths, along with storm surge and run-up using a Bayesian network. The Bayesian approach captures the uncertainty of inputs and predictions through the conditional probabilities between variables. Three versions of the barrier island response Bayesian network were tested for use on the Gold Coast. One network has the same structure as the original and was trained with the Santa Rosa Island data. The second network has a modified design and was trained using only pre- and post-storm data from 1988-2009 for the Gold Coast. The third version of the network has the same design as the second version of the network and was trained with the combined data from the Gold Coast and Santa Rosa Island. The two networks modified for use on the Gold Coast hindcast dune retreat with equal accuracy. Both networks explained 60% of the observed dune retreat variance, which is comparable to the skill observed by Plant and Stockdon (2012) in the initial Bayesian network application at Santa Rosa Island. The new networks improved predictions relative to application of the original network on the Gold Coast. Dune width was the most important morphologic variable in hindcasting dune retreat, while hydrodynamic variables, surge and

  14. Late Pleistocene dune activity in the central Great Plains, USA

    Science.gov (United States)

    Mason, J.A.; Swinehart, J.B.; Hanson, P.R.; Loope, D.B.; Goble, R.J.; Miao, X.; Schmeisser, R.L.

    2011-01-01

    Stabilized dunes of the central Great Plains, especially the megabarchans and large barchanoid ridges of the Nebraska Sand Hills, provide dramatic evidence of late Quaternary environmental change. Episodic Holocene dune activity in this region is now well-documented, but Late Pleistocene dune mobility has remained poorly documented, despite early interpretations of the Sand Hills dunes as Pleistocene relicts. New optically stimulated luminescence (OSL) ages from drill cores and outcrops provide evidence of Late Pleistocene dune activity at sites distributed across the central Great Plains. In addition, Late Pleistocene eolian sands deposited at 20-25 ka are interbedded with loess south of the Sand Hills. Several of the large dunes sampled in the Sand Hills clearly contain a substantial core of Late Pleistocene sand; thus, they had developed by the Late Pleistocene and were fully mobile at that time, although substantial sand deposition and extensive longitudinal dune construction occurred during the Holocene. Many of the Late Pleistocene OSL ages fall between 17 and 14 ka, but it is likely that these ages represent only the later part of a longer period of dune construction and migration. At several sites, significant Late Pleistocene or Holocene large-dune migration also probably occurred after the time represented by the Pleistocene OSL ages. Sedimentary structures in Late Pleistocene eolian sand and the forms of large dunes potentially constructed in the Late Pleistocene both indicate sand transport dominated by northerly to westerly winds, consistent with Late Pleistocene loess transport directions. Numerical modeling of the climate of the Last Glacial Maximum has often yielded mean monthly surface winds southwest of the Laurentide Ice Sheet that are consistent with this geologic evidence, despite strengthened anticyclonic circulation over the ice sheet. Mobility of large dunes during the Late Pleistocene on the central Great Plains may have been the result of

  15. Non-equilibrium flow and sediment transport distribution over mobile river dunes

    Science.gov (United States)

    Hoitink, T.; Naqshband, S.; McElroy, B. J.

    2017-12-01

    Flow and sediment transport are key processes in the morphodynamics of river dunes. During floods in several rivers (e.g., the Elkhorn, Missouri, Niobrara, and Rio Grande), dunes are observed to grow rapidly as flow strength increases, undergoing an unstable transition regime, after which they are washed out in what is called upper stage plane bed. This morphological evolution of dunes to upper stage plane bed is the strongest bed-form adjustment during non-equilibrium flows and is associated with a significant change in hydraulic roughness and water levels. Detailed experimental investigations, however, have mostly focused on fixed dunes limited to equilibrium flow and bed conditions that are rare in natural channels. Our understanding of the underlying sedimentary processes that result into the washing out of dunes is therefore very limited. In the present study, using the Acoustic Concentration and Velocity Profiler (ACVP), we were able to quantify flow structure and sediment transport distribution over mobile non-equilibrium dunes. Under these non-equilibrium flow conditions average dune heights were decreasing while dune lengths were increasing. Preliminary results suggest that this morphological behaviour is due to a positive phase lag between sediment transport maximum and topographic maximum leading to a larger erosion on the dune stoss side compared to deposition on dune lee side.

  16. Coastal and Marine Environment Problems in East Kalimantan Province

    OpenAIRE

    Supriharyono

    2000-01-01

    Coastal and marine problems were collected from the coastal community in area of the Municipality of Balikpapan East Kalimantan Province, from fishermen, NGO's and government officials. The technique used was that of the Field Participatory Workshop's. the result of the study revealed some coastal community awarenees, coastal resources USAge, and governmental policy. The local government's failure to solve those problems was mainly due to lack of social awarenees for environmental coastal man...

  17. Effects of ocean acidification on primary production in a coastal North Sea phytoplankton community

    NARCIS (Netherlands)

    Eberlein, Tim; Wohlrab, Sylke; Rost, Björn; John, Uwe; Bach, Lennart T.; Riebesell, U.; Van de Waal, D.B.

    2017-01-01

    We studied the effect of ocean acidification (OA) on a coastal North Sea plankton community in a long-term mesocosm CO2-enrichment experiment (BIOACID II long-term mesocosm study). From March to July 2013, 10 mesocosms of 19 m length with a volume of 47.5 to 55.9 m3 were deployed in the Gullmar

  18. Nekton community structure varies in response to coastal urbanization near mangrove tidal tributaries

    Science.gov (United States)

    Krebs, Justin M.; McIvor, Carole C.; Bell, Susan S.

    2014-01-01

    To assess the potential influence of coastal development on estuarine-habitat quality, we characterized land use and the intensity of land development surrounding small tidal tributaries in Tampa Bay. Based on this characterization, we classified tributaries as undeveloped, industrial, urban, or man-made (i.e., mosquito-control ditches). Over one third (37 %) of the tributaries have been heavily developed based on landscape development intensity (LDI) index values >5.0, while fewer than one third (28 %) remain relatively undeveloped (LDI < 3.0). We then examined the nekton community from 11 tributaries in watersheds representing the four defined land-use classes. Whereas mean nekton density was independent of land use, species richness and nekton-community structure were significantly different between urban and non-urban (i.e., undeveloped, industrial, man-made) tributaries. In urban creeks, the community was species-poor and dominated by high densities of poeciliid fishes, Poecilia latipinna and Gambusia holbrooki, while typically dominant estuarine taxa including Menidia spp., Fundulus grandis, and Adinia xenica were in low abundance and palaemonid grass shrimp were nearly absent. Densities of economically important taxa in urban creeks were only half that observed in five of the six undeveloped or industrial creeks, but were similar to those observed in mosquito ditches suggesting that habitat quality in urban and mosquito-ditch tributaries is suboptimal compared to undeveloped tidal creeks. Furthermore, five of nine common taxa were rarely collected in urban creeks. Our results suggest that urban development in coastal areas has the potential to alter the quality of habitat for nekton in small tidal tributaries as reflected by variation in the nekton community.

  19. Application of State of Art Modeling Techniques to Predict Flooding and Waves for an Exposed Coastal Area

    Directory of Open Access Journals (Sweden)

    Malcolm L. Spaulding

    2017-02-01

    Full Text Available Flood Insurance Rate Maps (FIRMs are developed by the Federal Emergency Management Agency (FEMA to provide guidance in establishing the risk to structures and infrastructure in the coastal zone from storm surge and coincidental waves. The maps are used by state agencies and municipalities to help guide coastal planning and establish the minimum elevation standard for new or substantially improved structures. A summary of the methods used and results of 2012 FIRM mapping are presented for Charlestown, RI; a coastal community located along the exposed, southern shoreline of the state. Concerns with the methods used in the 2012 analysis are put in context with the National Research Council’s (NRC 2009 review of the FEMA coastal mapping program. New mapping is then performed using state of the art, fully coupled surge and wave modeling and data analysis methods to address the concerns in the NRC review. The new maps and methodologies are in compliance with FEMA regulations and guidelines. The approach makes extensive use of the numerical modeling results from the recent US Army Corp of Engineers (USACE, North Atlantic Coast Comprehensive Study (NACCS 2015. Revised flood maps are presented and compared with the 2012 FIRM map to provide insight into the differences. The new maps highlight the importance of developing better estimates of offshore surge dynamics and its coupling to waves, dune erosion based on local observations, and the advancement in nearshore mapping of waves in flood inundated areas by the use of state of the art, two-dimensional wave transformation models.

  20. Modeling Megacusps and Dune Erosion

    Science.gov (United States)

    Orzech, M.; Reniers, A. J.; Thornton, E. B.

    2009-12-01

    Megacusps are large, concave, erosional features of beaches, of O(200m) alongshore wavelength, which sometimes occur when rip channel bathymetry is present. It is commonly hypothesized that erosion of the dune and back beach will be greater at the alongshore locations of the megacusp embayments, principally because the beach width is narrower there and larger waves can more easily reach the dune toe (e.g., Short, J. Geol., 1979, Thornton, et al., Mar. Geol., 2007). At present, available field data in southern Monterey Bay provide some support for this hypothesis, but not enough to fully confirm or refute it. This analysis utilizes XBeach, a 2DH nearshore sediment transport model, to test the above hypothesis under a range of wave conditions over several idealized rip-megacusp bathymetries backed by dunes. Model results suggest that while specific wave conditions may result in erosional hot spots at megacusp embayments, other factors such as tides, wave direction, and surf zone bathymetry can often play an equal or stronger role.

  1. Evolution of the Rømø barrier island in the Wadden Sea: Impacts of sea-level change on coastal morphodynamics

    DEFF Research Database (Denmark)

    Clemmensen, Lars B; Andersen, Thorbjørn Joest; Johannessen, Peter

    , and falling sea-level, whereas wash-over sedimentation was promoted during periods of rapid sea-level rise when shoreface, beach and coastal dune deposits were reworked. In contrast, lagoonal sedimentation has been relatively continuous and kept pace with the long-term Holocene sea-level rise. Our findings...

  2. Latitudinal and altitudinal controls of Titan's dune field morphometry

    Science.gov (United States)

    Le Gall, A.; Hayes, A. G.; Ewing, R.; Janssen, M. A.; Radebaugh, J.; Savage, C.; Encrenaz, P.; the Cassini Radar Team

    2012-01-01

    Dune fields dominate ˜13% of Titan's surface and represent an important sink of carbon in the methane cycle. Herein, we discuss correlations in dune morphometry with altitude and latitude. These correlations, which have important implications in terms of geological processes and climate on Titan, are investigated through the microwave electromagnetic signatures of dune fields using Cassini radar and radiometry observations. The backscatter and emissivity from Titan's dune terrains are primarily controlled by the amount of interdune area within the radar footprint and are also expected to vary with the degree of the interdunal sand cover. Using SAR-derived topography, we find that Titan's main dune fields (Shangri-La, Fensal, Belet and Aztlan) tend to occupy the lowest elevation areas in Equatorial regions occurring at mean elevations between ˜-400 and ˜0 m (relative to the geoid). In elevated dune terrains, we show a definite trend towards a smaller dune to interdune ratio and possibly a thinner sand cover in the interdune areas. A similar correlation is observed with latitude, suggesting that the quantity of windblown sand in the dune fields tends to decrease as one moves farther north. The altitudinal trend among Titan's sand seas is consistent with the idea that sediment source zones most probably occur in lowlands, which would reduce the sand supply toward elevated regions. The latitudinal preference could result from a gradual increase in dampness with latitude due to the asymmetric seasonal forcing associated with Titan's current orbital configuration unless it is indicative of a latitudinal preference in the sand source distribution or wind transport capacity.

  3. Zooming in on neutrino oscillations with DUNE

    Science.gov (United States)

    Srivastava, Rahul; Ternes, Christoph A.; Tórtola, Mariam; Valle, José W. F.

    2018-05-01

    We examine the capabilities of the DUNE experiment as a probe of the neutrino mixing paradigm. Taking the current status of neutrino oscillations and the design specifications of DUNE, we determine the experiment's potential to probe the structure of neutrino mixing and C P violation. We focus on the poorly determined parameters θ23 and δC P and consider both two and seven years of run. We take various benchmarks as our true values, such as the current preferred values of θ23 and δC P, as well as several theory-motivated choices. We determine quantitatively DUNE's potential to perform a precision measurement of θ23, as well as to test the C P violation hypothesis in a model-independent way. We find that, after running for seven years, DUNE will make a substantial step in the precise determination of these parameters, bringing to quantitative test the predictions of various theories of neutrino mixing.

  4. Influence of salinity on bacterioplankton communities from the brazilian rain forest to the coastal Atlantic Ocean

    OpenAIRE

    Silveira, Cynthia Barbosa da; Vieira, Ricardo Pilz; Cardoso, Alexander Machado; Paranhos, Rodolfo Pinheiro da Rocha; Albano, Rodolpho Mattos; Martins, Orlando Bonifácio

    2011-01-01

    BACKGROUND: Planktonic bacteria are recognized as important drivers of biogeochemical processes in all aquatic ecosystems, however, the taxa that make up these communities are poorly known. The aim of this study was to investigate bacterial communities in aquatic ecosystems at Ilha Grande, Rio de Janeiro, Brazil, a preserved insular environment of the Atlantic rain forest and how they correlate with a salinity gradient going from terrestrial aquatic habitats to the coastal Atlantic Ocean. MET...

  5. Environmental conditions and biotic communities in Foz de Almargem and Salgados coastal lagoons, Algarve (South Portugal)

    OpenAIRE

    Coelho, Susana Isabel Eusébio

    2013-01-01

    The present study intended to compare environmental conditions and biotic communities of two choked coastal lagoons located in the Algarve region, Foz de Almargem and Salgados, with the purpose of evaluating the effects of organic pollution from wastewater discharges in water quality and biotic communities from different levels of the food chain, namely phytoplankton and benthic macroinvertebrates. Both lagoons were seasonally connected to the sea, but most of the year they were isolated r...

  6. Dark Side of Development: Modernity, Disaster Risk and Sustainable Livelihoods in Two Coastal Communities in Fiji

    OpenAIRE

    Per Becker

    2017-01-01

    The world is changing rapidly, as are the remotest rural communities. Modernity is spreading across the world under the guise of development and it is transforming disaster risk. This raises issues concerning how disaster risk is changing in such milieus. Using a sustainable livelihood approach, this article investigates access to different types of capital that central to the vulnerability of two coastal communities in Fiji that are affected by modernity to different extents. This comparativ...

  7. Keeping our charm: residents, growth, and quality of life issues in a small but growing Texas coastal community

    Science.gov (United States)

    Jiaying Lu; Michael A. Schuett

    2009-01-01

    This study assessed residents' perceptions of quality of life, conservation, and growth in a small, fast-growing coastal community. Data were collected from an on-site survey in Aransas County, TX, from 2006 to 2007. Results show that the residents are concerned about preserving their natural resources, maintaining a small-town atmosphere in their community, and...

  8. Linking social, ecological, and physical science to advance natural and nature-based protection for coastal communities.

    Science.gov (United States)

    Arkema, Katie K; Griffin, Robert; Maldonado, Sergio; Silver, Jessica; Suckale, Jenny; Guerry, Anne D

    2017-07-01

    Interest in the role that ecosystems play in reducing the impacts of coastal hazards has grown dramatically. Yet the magnitude and nature of their effects are highly context dependent, making it difficult to know under what conditions coastal habitats, such as saltmarshes, reefs, and forests, are likely to be effective for saving lives and protecting property. We operationalize the concept of natural and nature-based solutions for coastal protection by adopting an ecosystem services framework that propagates the outcome of a management action through ecosystems to societal benefits. We review the literature on the basis of the steps in this framework, considering not only the supply of coastal protection provided by ecosystems but also the demand for protective services from beneficiaries. We recommend further attention to (1) biophysical processes beyond wave attenuation, (2) the combined effects of multiple habitat types (e.g., reefs, vegetation), (3) marginal values and expected damage functions, and, in particular, (4) community dependence on ecosystems for coastal protection and co-benefits. We apply our approach to two case studies to illustrate how estimates of multiple benefits and losses can inform restoration and development decisions. Finally, we discuss frontiers for linking social, ecological, and physical science to advance natural and nature-based solutions to coastal protection. © 2017 New York Academy of Sciences.

  9. Impacts of a lengthening open water season on Alaskan coastal communities: deriving locally relevant indices from large-scale datasets and community observations

    Science.gov (United States)

    Rolph, Rebecca J.; Mahoney, Andrew R.; Walsh, John; Loring, Philip A.

    2018-05-01

    Using thresholds of physical climate variables developed from community observations, together with two large-scale datasets, we have produced local indices directly relevant to the impacts of a reduced sea ice cover on Alaska coastal communities. The indices include the number of false freeze-ups defined by transient exceedances of ice concentration prior to a corresponding exceedance that persists, false break-ups, timing of freeze-up and break-up, length of the open water duration, number of days when the winds preclude hunting via boat (wind speed threshold exceedances), the number of wind events conducive to geomorphological work or damage to infrastructure from ocean waves, and the number of these wind events with on- and along-shore components promoting water setup along the coastline. We demonstrate how community observations can inform use of large-scale datasets to derive these locally relevant indices. The two primary large-scale datasets are the Historical Sea Ice Atlas for Alaska and the atmospheric output from a regional climate model used to downscale the ERA-Interim atmospheric reanalysis. We illustrate the variability and trends of these indices by application to the rural Alaska communities of Kotzebue, Shishmaref, and Utqiaġvik (previously Barrow), although the same procedure and metrics can be applied to other coastal communities. Over the 1979-2014 time period, there has been a marked increase in the number of combined false freeze-ups and false break-ups as well as the number of days too windy for hunting via boat for all three communities, especially Utqiaġvik. At Utqiaġvik, there has been an approximate tripling of the number of wind events conducive to coastline erosion from 1979 to 2014. We have also found a delay in freeze-up and earlier break-up, leading to a lengthened open water period for all of the communities examined.

  10. Impacts of a lengthening open water season on Alaskan coastal communities: deriving locally relevant indices from large-scale datasets and community observations

    Directory of Open Access Journals (Sweden)

    R. J. Rolph

    2018-05-01

    Full Text Available Using thresholds of physical climate variables developed from community observations, together with two large-scale datasets, we have produced local indices directly relevant to the impacts of a reduced sea ice cover on Alaska coastal communities. The indices include the number of false freeze-ups defined by transient exceedances of ice concentration prior to a corresponding exceedance that persists, false break-ups, timing of freeze-up and break-up, length of the open water duration, number of days when the winds preclude hunting via boat (wind speed threshold exceedances, the number of wind events conducive to geomorphological work or damage to infrastructure from ocean waves, and the number of these wind events with on- and along-shore components promoting water setup along the coastline. We demonstrate how community observations can inform use of large-scale datasets to derive these locally relevant indices. The two primary large-scale datasets are the Historical Sea Ice Atlas for Alaska and the atmospheric output from a regional climate model used to downscale the ERA-Interim atmospheric reanalysis. We illustrate the variability and trends of these indices by application to the rural Alaska communities of Kotzebue, Shishmaref, and Utqiaġvik (previously Barrow, although the same procedure and metrics can be applied to other coastal communities. Over the 1979–2014 time period, there has been a marked increase in the number of combined false freeze-ups and false break-ups as well as the number of days too windy for hunting via boat for all three communities, especially Utqiaġvik. At Utqiaġvik, there has been an approximate tripling of the number of wind events conducive to coastline erosion from 1979 to 2014. We have also found a delay in freeze-up and earlier break-up, leading to a lengthened open water period for all of the communities examined.

  11. Impact of lengthening open water season on food security in Alaska coastal communities: Global impacts may outweigh local "frontline" effects

    Science.gov (United States)

    Rolph, R.; Mahoney, A. R.

    2015-12-01

    Using ice concentration data from the Alaska Sea Ice Atlas from 1953-2013 for selected communities in Alaska, we find a consistent trend toward later freeze up and earlier breakup, leading a lengthened open water period. Such changes are often considered to bring a variety of "frontline" local impacts to Arctic coastal communities such as increased rates of coastal erosion. However, direct consequences of these changes to local food security (e.g. through impacts on subsistence activities and marine transport of goods) may be outweighed at least in the short term by the effects of large scale Arctic sea ice change coupled with global oil markets. For example, a later freeze-up might delay local hunters' transition from boats to snow-machines, but whether this trend will affect hunting success, especially in the next few years, is uncertain. Likewise, the magnitude of change in open water season length is unlikely to be sufficient to increase the frequency with which communities are served by barges. However, an expanding open water season throughout the Arctic has implications for the global economy, which can have indirect effects on local communities. In the Chukchi and Beaufort Seas, where rapid sea ice change has been accompanied by increased interest in oil and gas development, the U.S. Bureau of Ocean Energy Management currently requires drilling operations to cease 38 days prior to freeze up. Taking this into account, the lengthening open water season has effectively extended the drilling season for oil companies by 184% since the 1950s. If oil development goes ahead, local communities will likely experience a range of indirect impacts on food security due to increased vessel traffic and demand on infrastructure coupled with changes in local economies and employment opportunities. Increased likelihood of an oil spill in coastal waters also poses a significant threat to local food security. Thus, while Arctic coastal communities are already experiencing

  12. Frost-covered dunes

    Science.gov (United States)

    1999-01-01

    MOC image of dunes in Chasma Boreale, a giant trough in the north polar cap. This September 1998 view shows dark sand emergent from beneath a veneer of bright frost left over from the northern winter that ended in July 1998.

  13. Construction of an Environmentally Sustainable Development on a Modified Coastal Sand Mined and Landfill Site—Part 2. Re-Establishing the Natural Ecosystems on the Reconstructed Beach Dunes

    Directory of Open Access Journals (Sweden)

    Anne-Laure Markovina

    2010-03-01

    Full Text Available Mimicking natural processes lead to progressive colonization and stabilization of the reconstructed beach dune ecosystem, as part of the ecologically sustainable development of Magenta Shores, on the central coast of New South Wales, Australia. The retained and enhanced incipient dune formed the first line of storm defence. Placement of fibrous Leptospermum windrows allowed wind blown sand to form crests and swales parallel to the beach. Burial of Spinifex seed head in the moist sand layer achieved primary colonization of the reconstructed dune and development of a soil fungal hyphae network prior to introduction of secondary colonizing species. Monitoring stakes were used as roosts by birds, promoting re-introduction of native plant species requiring germination by digestive tract stimulation. Bush regeneration reduced competition from weeds, allowing native vegetation cover to succeed. On-going weeding and monitoring are essential at Magenta Shores until bitou bush is controlled for the entire length of beach. The reconstructed dunes provide enhanced protection from sand movement and storm bite, for built assets, remnant significant vegetation and sensitive estuarine ecosystems.

  14. First quantification of relationship between dune orientation and sediment availability, Olympia Undae, Mars

    Science.gov (United States)

    Fernandez-Cascales, Laura; Lucas, Antoine; Rodriguez, Sébastien; Gao, Xin; Spiga, Aymeric; Narteau, Clément

    2018-05-01

    Dunes provide unique information about wind regimes on planetary bodies where there is no direct meteorological data. At the eastern margin of Olympia Undae on Mars, dune orientation is measured from satellite imagery and sediment cover is estimated using the high contrast between the dune material and substrate. The analysis of these data provide the first quantification of relationship between sediment availability and dune orientation. Abrupt and smooth dune reorientations are associated with inward and outward dynamics of dunes approaching and ejecting from major sedimentary bodies, respectively. These reorientation patterns along sediment transport pathways are interpreted using a new generation dune model based on the coexistence of two dune growth mechanisms. This model also permits solving of the inverse problem of predicting the wind regime from dune orientation. For bidirectional wind regimes, solutions of this inverse problem show substantial differences in the distributions of sediment flux orientation, which can be attributed to atmospheric flow variations induced by changes in albedo at the boundaries of major dune fields. Then, we conclude that relationships between sediment cover and dune orientation can be used to constrain wind regime and dune field development on Mars and other planetary surfaces.

  15. Predicting impact of SLR on coastal flooding in Banda Aceh coastal defences

    Science.gov (United States)

    Al'ala, Musa; Syamsidik, Kato, Shigeru

    2017-10-01

    Banda Aceh is a low-lying city located at the northern tip of Sumatra Island and situated at the conjuncture of Malacca Strait and the Andaman Sea. A Sea Level Rise (SLR) rate at 7 mm/year has been observed around this region. In the next 50 years, this city will face a serious challenge to encounter impacts of the sea level rise, such as frequent coastal floodings. This study is aimed at estimating impacts of the sea level rise induced coastal floodings on several types of coastal structures and city drainage system. Numerical simulations of Delft3D were applied to investigate the influence of the gradual sea level rise in 50 years. The hydrodynamic process of coastal flooding and sediment transport were simulated by Delft3D-Flow. Topography and bathymetry data were collected from GEBCO and updated with the available nautical chart (DISHIDROS, JICA, and field measurements). Hydrodynamic process gains the flow process revealing the level of the sea water intrusion also observed in the model. Main rivers (Krueng Aceh, Krueng Neng, and Alue Naga Flood Canal) and the drainage system were observed to see the tides effects on coastal structures and drainage system. The impact on coastal community focusing on affected area, shoreline retreat, the rate of sea intrusion was analyzed with spatial tools. New coastal line, coastal flooding vulnerable area, and the community susceptibility properties map influenced by 50 years sea level rise is produced. This research found that the city needs to address strategies to anticipate the exacerbating impacts of the sea level rise by managing its coastal spatial planning and modify its drainage system, especially at the drainage outlets.

  16. Coastal microbial mat diversity along a natural salinity gradient.

    Directory of Open Access Journals (Sweden)

    Henk Bolhuis

    Full Text Available The North Sea coast of the Dutch barrier island of Schiermonnikoog is covered by microbial mats that initiate a succession of plant communities that eventually results in the development of a densely vegetated salt marsh. The North Sea beach has a natural elevation running from the low water mark to the dunes resulting in gradients of environmental factors perpendicular to the beach. These gradients are due to the input of seawater at the low water mark and of freshwater from upwelling groundwater at the dunes and rainfall. The result is a natural and dynamic salinity gradient depending on the tide, rainfall and wind. We studied the microbial community composition in thirty three samples taken every ten meters along this natural salinity gradient by using denaturing gradient gel electrophoresis (DGGE of rRNA gene fragments. We looked at representatives from each Domain of life (Bacteria, Archaea and Eukarya and with a particular emphasis on Cyanobacteria. Analysis of the DGGE fingerprints together with pigment composition revealed three distinct microbial mat communities, a marine community dominated by diatoms as primary producers, an intermediate brackish community dominated by Cyanobacteria as primary producers and a freshwater community with Cyanobacteria and freshwater green algae.

  17. Possibility of star (pyramid) dune development in the area of bimodal wind regime

    Science.gov (United States)

    Biejat, K.

    2012-04-01

    Star (pyramid) dunes are the largest aeolian landforms. They can occur in three types - simple, complex and compound. Development of this type of dunes is usually connected with multidirectional or complex wind regimes. The aim of this study was to verify a hypothesis that the star dunes can also develop by a bimodal wind regime and by local modifications of nearsurface wind flow directions. Field study was performed on Erg Chebbi, in southern Morocco. Several star and transverse dunes were selected for the study of their shape. The star dunes were analysed concerning their type and position in the dune field. This erg contains all of three types of star dunes together with transverse dunes. The regional wind data show that there are two dominant wind directions - NE (Chergui) and SW (Saheli). To determine the difference in shape of star dunes, we performed topographic surveying by GPS RTK. The results allowed to create 3D models of star dunes. The models were used to determine metric characteristics of star dunes, including area of dune basis, volume, and slope angles. On the basis of 3D models, primary, secondary and, on the compound dunes, tertiary arms were determined. Primary arms on each type of star dunes, as well as crestlines of transverse dunes, have dominant orientation NW-SE, perpendicular to two dominant wind directions. This clearly confirms that star dunes of Erg Chebbi develop by a bimodal wind regime In contrast to primary arms, subsidiary (secondary and tertiary) arms are not connected to general wind regime. The secondary arms of star dunes occur to be differentially developer. There are more subsidiary arms on SW sides in comparison to the E sides of the dunes where inclination of slopes is constant. It can be therefore inferred that sand has been supplied predominantly from SW direction. This is supported by distribution of the dunes on the erg. Most compound star dunes compose a chain along the E margin of the erg. Comparison of compound star

  18. Insect biodiversity of the Algodones Dunes of California

    Directory of Open Access Journals (Sweden)

    Lynn Kimsey

    2017-11-01

    Full Text Available Over a nine year period beginning in 2007 we surveyed the insects of the Algodones Dunes, Imperial Count, California, as part of a study undertaken for the U.S. Bureau of Land Management. In a series of 22 collecting trips ranging in duration from 2 to 8 days we thus far have accumulated records of 1,840 species, 21 orders and 244 families from the dunes. Hymenoptera constituted the most diverse order, comprising about 45% of all the species recovered. Insect diversity and abundance peaked during the hottest part of the year between the months of May and September. Life history traits of the insects sampled included herbivores (29.6%, parasitoids (28.7%, predators (18.1%, pollen/nectar feeders (10.9%, detritivores (6.2% and scavengers (2.4%. Seventy-nine or 4% of the insect species collected in the dunes have been solely recorded from there, and 3% of the species almost certainly derive from adjacent aquatic habitats or agricultural ecosystems, as their life histories could not be completed in Algodones Dunes habitat. The insect fauna of the Algodones Dunes is unexpectedly rich and diverse.

  19. Increasing tsunami preparedness through educator professional development in coastal Cascadia communities

    Science.gov (United States)

    Pratt-Sitaula, B. A.; Butler, R. F.; Hunter, N.; Lillie, R. J.; Magura, B.; Groom, R.; Johnson, J. A.; Coe, M.

    2016-12-01

    Increasing society's ability to mitigate risks is one of the major goals of geohazard research. Therefore part of tsunami science research must be finding effective ways to communicate scientific findings to the public to be used in community preparedness plans. The "Cascadia EarthScope Earthquake and Tsunami Education Program" (CEETEP; ceetep.oregonstate.edu) has worked to bridge the gap between scientific researchers and the public by providing professional development workshops for educators from coastal communities in Oregon, Washington, and northern California. CEETEP translates cutting edge EarthScope and other geoscience research into educational resources appropriate for K-12 teachers, park and museum interpreters, and emergency management outreach educators and their learners. Local educators have the potential to reach a wide segment of coastal residents. The tsunami generated by the next Great Cascadia Subduction Zone earthquake will arrive only 10-30 minutes after shaking, making mitigation and community-wide education an imperative. An essential component of CEETEP is collaboration with experts in science, pedagogy, and emergency preparedness. CEETEP provided two 4-day workshops and a follow-up Share-a-thon each year for three years (2013-2015). 151 educators participated in the program. Results from CEETEP are very encouraging. Participant content knowledge improved from 49% to 82% over the course of the workshop. Similarly, confidence in teaching about workshop topics increased from an average of 3.0 to 5.3 on a 6-point scale. Participant optimism about the efficacy and tractability of community-level planning also increased from 6.1 to 7.8 on a 9-point scale. Nearly 90% of participants continued to be active with the program through their March Share-a-thon and presented on a wide range of activities that they and their learners undertook related to earthquake and tsunami science and preparedness. Participants were also quite favorable about the

  20. Southern high latitude dune fields on Mars: Morphology, aeolian inactivity, and climate change

    Science.gov (United States)

    Fenton, L.K.; Hayward, R.K.

    2010-01-01

    In a study area spanning the martian surface poleward of 50?? S., 1190 dune fields have been identified, mapped, and categorized based on dune field morphology. Dune fields in the study area span ??? 116400km2, leading to a global dune field coverage estimate of ???904000km2, far less than that found on Earth. Based on distinct morphological features, the dune fields were grouped into six different classes that vary in interpreted aeolian activity level from potentially active to relatively inactive and eroding. The six dune field classes occur in specific latitude zones, with a sequence of reduced activity and degradation progressing poleward. In particular, the first signs of stabilization appear at ???60?? S., which broadly corresponds to the edge of high concentrations of water-equivalent hydrogen content (observed by the Neutron Spectrometer) that have been interpreted as ground ice. This near-surface ground ice likely acts to reduce sand availability in the present climate state on Mars, stabilizing high latitude dunes and allowing erosional processes to change their morphology. As a result, climatic changes in the content of near-surface ground ice are likely to influence the level of dune activity. Spatial variation of dune field classes with longitude is significant, suggesting that local conditions play a major role in determining dune field activity level. Dune fields on the south polar layered terrain, for example, appear either potentially active or inactive, indicating that at least two generations of dune building have occurred on this surface. Many dune fields show signs of degradation mixed with crisp-brinked dunes, also suggesting that more than one generation of dune building has occurred since they originally formed. Dune fields superposed on early and late Amazonian surfaces provide potential upper age limits of ???100My on the south polar layered deposits and ???3Ga elsewhere at high latitudes. No craters are present on any identifiable dune

  1. Holocene eolian activity in the Minot dune field, North Dakota

    Science.gov (United States)

    Muhs, D.R.; Stafford, Thomas W.; Been, J.; Mahan, S.A.; Burdett, J.; Skipp, G.; Rowland, Z.M.

    1997-01-01

    Stabilized eolian sand is common over much of the Great Plains region of the United States and Canada, including a subhumid area of ??? 1500 km2 near Minot, North Dakota. Eolian landforms consist of sand sheets and northwest-trending parabolic dunes. Dunes and sand sheets in the Minot field are presently stabilized by a cover of prairie grasses or oak woodland. Stratigraphic studies and accelerator mass spectrometry radiocarbon dating of paleosols indicate at least two periods of eolian sand movement in the late Holocene. Pedologic data suggest that all of the dune field has experienced late Holocene dune activity, though not all parts of the dune field may have been active simultaneously. Similar immobile element (Ti, Zr, La, Ce) concentrations support the interpretation that eolian sands are derived from local glaciofluvial and glaciolacustrine sediments. However, glaciolacustrine and glaciofluvial source sediments have high Ca concentrations from carbonate minerals, whereas dune sands are depleted in Ca. Because noneolian-derived soils in the area are calcareous, these data indicate that the Minot dune field may have had extended periods of activity in the Holocene, such that eolian abrasion removed soft carbonate minerals. The southwest-facing parts of some presently stabilized dunes were active during the 1930s drought, but were revegetated during the wetter years of the 1940s. These observations indicate that severe droughts accompanied by high temperatures are the most likely cause of Holocene eolian activity.

  2. Community-Based Coastal Resource Management (CB-CRM: a Case Study f Mariveles, Bataan, Philippines

    Directory of Open Access Journals (Sweden)

    Andrew Lou L. Mungcal

    2013-11-01

    Full Text Available This paper addressed the issue of sustainable coastal resource management through a successful Community-Based Coastal Resource Management (CB-CRM Program in the Municipality of Mariveles, province of Bataan in the Philippines. The paper investigated how governance and institutional and legislative framework, and the concept of sustainable development complemented each other to promote good local eco-governance in the management and protection of finite local marine resources. Specifically, it analyzed how the local fisherfolk community of Mariveles utilized efficiently their finite marine resources in the context of eco-governance. It also investigated how the cooperative efforts of various stakeholders: peoples’ organizations (POs, local government unit (LGU, and a non-government organization (NGO in Mariveles, Bataan affected their coastal resources against environmental degradation and exploitation. This paper would benefit POs, LGUs, and NGOs in their quest for sustainable management and conservation of their limited coastal resources. This paper yielded the following findings. First, POs and NGOs engage when NGOs can strengthen the POs’ capacity building through the transfer of skills and technology, when NGOs can enhance the POs’ indigenous knowledge, and when NGOs are more knowledgeable of formal venues of LGU participation. Second, LGUs, NGOs and POs engage when POs and NGOs can complement each other to strengthen their capacity building, and when NGOs can help implement environmental programs that are beneficial to the POs. Third, NGOs and POs engage when POs are threatened by elite power, and when NGOs want their environmental issues on LGU’s legislative agenda. Finally, NGOs and POs engage when they see possible LGU cooperation. Participant observation through focus group discussion (FGD and key informants’ interview of different stakeholders was a primary source of information in formulating the aforementioned conclusions

  3. A comparison of seed banks across a sand dune successional gradient at Lake Michigan dunes (Indiana, USA)

    Science.gov (United States)

    Leicht-Young, S. A.; Pavlovic, N.B.; Grundel, R.; Frohnapple, K.J.

    2009-01-01

    In habitats where disturbance is frequent, seed banks are important for the regeneration of vegetation. Sand dune systems are dynamic habitats in which sand movement provides intermittent disturbance. As succession proceeds from bare sand to forest, the disturbance decreases. At Indiana Dunes National Lakeshore, we examined the seed banks of three habitat types across a successional gradient: foredunes, secondary dunes, and oak savanna. There were differences among the types of species that germinated from each of the habitats. The mean seed bank density increased across the successional gradient by habitat, from 376 to 433 to 968 seeds m-2, but with foredune and secondary dune seed bank densities being significantly lower than the savanna seed bank density. The number of seeds germinated was significantly correlated with soil organic carbon, demonstrating for this primary successional sequence that seed density increases with stage and age. The seed bank had much lower species richness than that of the aboveground vegetation across all habitats. Among sites within a habitat type, the similarity of species germinated from the seed banks was very low, illustrating the variability of the seed bank even in similar habitat types. These results suggest that restoration of these habitats cannot rely on seed banks alone. ?? 2008 Springer Science+Business Media B.V.

  4. Characteristics and environmental carrying capacities of coastal area in Yogyakarta Special Region for aquaculture

    Science.gov (United States)

    Triyatmo, B.; Rustadi; Priyono, S. B.

    2018-03-01

    The purpose of this study were to determine characteristics and environmental carrying capacities of coastal area in Yogyakarta Special Region for aquaculture. This study was conducted in 2015 by characterizing land and water dynamics, land use, and the suitability of coastal environments for aquaculture. Evaluation on the coastal environments suitability for aquaculture ponds was based on the landforms, soil properties, water quality and land. Selection of coastal locations for aquaculture development was based on the level of suitability of coastal environment. The results showed that the coastal in Kulon Progo and Bantul Regencies were characterized by sand dune and beach ridge with sandy soil texture, while in Gunungkidul Regency was characterized by limestone hill with rocky texture. Water sources of the coastal area were the sea, river, and ground water with the salinity of 31–37, 7–11, 7–31 ppt and pH of 7.4–8.4 7.0–8.2 and 7.4–9.9, respectively. The coastal lands were used for seasonal/annual planting, ponds, fish landing sites, tourism areas and conservation areas. The coastal carrying capacity was rather suitable for aquaculture, especially in the sandy soil area. Aquaculture in that area can be done intensively for shrimp (Litopenaeus vannamei), using biocrete (biological material) or plastic sheet.

  5. An integrated approach shows different use of water resources from Mediterranean maquis species in a coastal dune ecosystem

    Directory of Open Access Journals (Sweden)

    F. Manes

    2009-11-01

    Full Text Available An integrated approach has been used to analyse the dependence of three Mediterranean species, A. unedo L., Q. ilex L., and P. latifolia L. co-occurring in a coastal dune ecosystem on two different water resources: groundwater and rainfed upper soil layers. The approach included leaf level gas exchanges, sap flow measurements and structural adaptations between 15 May and 31 July 2007. During this period it was possible to capture different species-specific response patterns to an environment characterized by a sandy soil, with a low water retention capacity, and the presence of a water table. The latter did not completely prevent the development of a drought response and, combined with previous studies in the same area, response differences between species have been partially attributed to different root distributions. Sap flow of A. unedo decreased rapidly with the decline of soil water content, while that of Q. ilex decreased only moderately. Midday leaf water potential of P. latifolia and A. unedo ranged between −2.2 and −2.7 MPa throughout the measuring period, while in Q. ilex it decreased down to −3.4 MPa at the end of the season. A. unedo was the only species that responded to drought with a decrease of its leaf area to sapwood area ratio from 23.9±1.2 (May to 15.2±1.5 (July. While A. unedo also underwent an almost stepwise loss on hydraulic conductivity, such a loss did not occur for Q. ilex, whereas P. latifolia was able to slightly increase its hydraulic conducitivity. These differences show how different plant compartments coordinate differently between species in their responses to drought. The different responses appear to be mediated by different root distributions of the species and their relative resistances to drought are likely to depend on the duration of the periods in which water remains extractable in the upper soil layers.

  6. An integrated approach shows different use of water resources from Mediterranean maquis species in a coastal dune ecosystem

    Science.gov (United States)

    Mereu, S.; Salvatori, E.; Fusaro, L.; Gerosa, G.; Muys, B.; Manes, F.

    2009-11-01

    An integrated approach has been used to analyse the dependence of three Mediterranean species, A. unedo L., Q. ilex L., and P. latifolia L. co-occurring in a coastal dune ecosystem on two different water resources: groundwater and rainfed upper soil layers. The approach included leaf level gas exchanges, sap flow measurements and structural adaptations between 15 May and 31 July 2007. During this period it was possible to capture different species-specific response patterns to an environment characterized by a sandy soil, with a low water retention capacity, and the presence of a water table. The latter did not completely prevent the development of a drought response and, combined with previous studies in the same area, response differences between species have been partially attributed to different root distributions. Sap flow of A. unedo decreased rapidly with the decline of soil water content, while that of Q. ilex decreased only moderately. Midday leaf water potential of P. latifolia and A. unedo ranged between -2.2 and -2.7 MPa throughout the measuring period, while in Q. ilex it decreased down to -3.4 MPa at the end of the season. A. unedo was the only species that responded to drought with a decrease of its leaf area to sapwood area ratio from 23.9±1.2 (May) to 15.2±1.5 (July). While A. unedo also underwent an almost stepwise loss on hydraulic conductivity, such a loss did not occur for Q. ilex, whereas P. latifolia was able to slightly increase its hydraulic conducitivity. These differences show how different plant compartments coordinate differently between species in their responses to drought. The different responses appear to be mediated by different root distributions of the species and their relative resistances to drought are likely to depend on the duration of the periods in which water remains extractable in the upper soil layers.

  7. Modelling dune evolution and dynamic roughness in rivers

    NARCIS (Netherlands)

    Paarlberg, Andries

    2008-01-01

    Accurate river flow models are essential tools for water managers, but these hydraulic simulation models often lack a proper description of dynamic roughness due to hysteresis effects in dune evolution. To incorporate the effects of dune evolution directly into the resistance coefficients of

  8. Community barcoding reveals little effect of ocean acidification on the composition of coastal plankton communities: Evidence from a long-term mesocosm study in the Gullmar Fjord, Skagerrak.

    Directory of Open Access Journals (Sweden)

    Julia A F Langer

    Full Text Available The acidification of the oceans could potentially alter marine plankton communities with consequences for ecosystem functioning. While several studies have investigated effects of ocean acidification on communities using traditional methods, few have used genetic analyses. Here, we use community barcoding to assess the impact of ocean acidification on the composition of a coastal plankton community in a large scale, in situ, long-term mesocosm experiment. High-throughput sequencing resulted in the identification of a wide range of planktonic taxa (Alveolata, Cryptophyta, Haptophyceae, Fungi, Metazoa, Hydrozoa, Rhizaria, Straminipila, Chlorophyta. Analyses based on predicted operational taxonomical units as well as taxonomical compositions revealed no differences between communities in high CO2 mesocosms (~ 760 μatm and those exposed to present-day CO2 conditions. Observed shifts in the planktonic community composition were mainly related to seasonal changes in temperature and nutrients. Furthermore, based on our investigations, the elevated CO2 did not affect the intraspecific diversity of the most common mesozooplankter, the calanoid copepod Pseudocalanus acuspes. Nevertheless, accompanying studies found temporary effects attributed to a raise in CO2. Differences in taxa composition between the CO2 treatments could, however, only be observed in a specific period of the experiment. Based on our genetic investigations, no compositional long-term shifts of the plankton communities exposed to elevated CO2 conditions were observed. Thus, we conclude that the compositions of planktonic communities, especially those in coastal areas, remain rather unaffected by increased CO2.

  9. Community barcoding reveals little effect of ocean acidification on the composition of coastal plankton communities: Evidence from a long-term mesocosm study in the Gullmar Fjord, Skagerrak.

    Science.gov (United States)

    Langer, Julia A F; Sharma, Rahul; Schmidt, Susanne I; Bahrdt, Sebastian; Horn, Henriette G; Algueró-Muñiz, María; Nam, Bora; Achterberg, Eric P; Riebesell, Ulf; Boersma, Maarten; Thines, Marco; Schwenk, Klaus

    2017-01-01

    The acidification of the oceans could potentially alter marine plankton communities with consequences for ecosystem functioning. While several studies have investigated effects of ocean acidification on communities using traditional methods, few have used genetic analyses. Here, we use community barcoding to assess the impact of ocean acidification on the composition of a coastal plankton community in a large scale, in situ, long-term mesocosm experiment. High-throughput sequencing resulted in the identification of a wide range of planktonic taxa (Alveolata, Cryptophyta, Haptophyceae, Fungi, Metazoa, Hydrozoa, Rhizaria, Straminipila, Chlorophyta). Analyses based on predicted operational taxonomical units as well as taxonomical compositions revealed no differences between communities in high CO2 mesocosms (~ 760 μatm) and those exposed to present-day CO2 conditions. Observed shifts in the planktonic community composition were mainly related to seasonal changes in temperature and nutrients. Furthermore, based on our investigations, the elevated CO2 did not affect the intraspecific diversity of the most common mesozooplankter, the calanoid copepod Pseudocalanus acuspes. Nevertheless, accompanying studies found temporary effects attributed to a raise in CO2. Differences in taxa composition between the CO2 treatments could, however, only be observed in a specific period of the experiment. Based on our genetic investigations, no compositional long-term shifts of the plankton communities exposed to elevated CO2 conditions were observed. Thus, we conclude that the compositions of planktonic communities, especially those in coastal areas, remain rather unaffected by increased CO2.

  10. Short-term versus long-term changes in the benthic communities of a small coastal lagoon: implications for ecological status assessment

    OpenAIRE

    Félix, PM; Chainho, P; Costa, Jl; Correia, MJ; Chaves, ML; Medeiros, JP; Cabral, HN; Wouters, N; Bernardo, J; Costa, AM; Cristo, M; Silva, G; Azeda, C; Tavares, P; Costa, MJ

    2013-01-01

    The characteristic high variability and low predictability of coastal lagoons, due to strong changes in marine and freshwater inputs, make these ecosystems an interesting casestudy. The small Melides landlocked coastal lagoon in SW Portugal is a paradigmatic example, with a biological community highly stressed by these phenomena. Benthic macroinvertebrate samples were collected in 1998/99 and 2009 and each year, in different seasons and addressing different environmental conditions i...

  11. Hydro-geochemical analysis of a degraded dune slack

    NARCIS (Netherlands)

    Grootjans, AP; Sival, FP; Stuyfzand, PJ

    A hydrochemical analysis of the groundwater composition was carried out in a degraded dune slack complex in order to assess the prospects for regeneration of low productivity, basiphilous vegetation types, typical of natural dune slacks. Two hundred and fifty water samples, most of them obtained

  12. Sustainable Eco Coastal Development Through Corporate Social Responsibility (CSR) Program

    Science.gov (United States)

    Rakhmanissazly, Arsi; Mursito Ardy, Yong; Abdullah

    2017-02-01

    Besides technical problems the company’s operational constraints that may effect high deficiency for the company is the company - community conflicts. Company - community conflict can also arise depends on the geographic conditions and characteristics of the community itself. Some studies has show that coastal community have higher level of social risk when compared to non-coastal community. Also, the coastal community ussually only rely on what sea provides as their main livelihood. Because of the level of education still contemtible the community couldn’t optimized the potential of their own area. Corporate Social Responsibility (CSR) har emerged as an important approach for addressing the social and environmental impact of company activities. Through CSR program, PT Pertamina EP Asset 3 Tambun Field (PEP) try to form value integration by utilizing resources from the community and the company by making sustainable eco - coastal living in Desa Tambaksari, Karawang, one of PEP working area. Using sustainable livelihood approach begin with compiling data by doing social mapping PEP has initiate the area to becoming Fish Processing Industry Centre. By implementing PDCA in every steps of the program, PEP has multiplied some other programs such as Organic Fish Feed Processing, Seaweed Farming and Waste Bank for Green Coastal Village. These program is PEP’s effort to create a sustainability environment by enhancing the community’s potentials as well as resolving social problems around Tambaksari. The most important result besides getting our license to operate from the community, is the community itself can grow into an eco coastal sustainable system.

  13. Environmental history and dating of coastal dunefields

    International Nuclear Information System (INIS)

    Illenberger, W.K.; Verhagen, B.T.

    1990-01-01

    Sand pulses can be inferred from the geomorphologic evolution of coastal dunefields over the last 6500 years in the eastern Cape Province, South Africa. These pulses correlate with erosion cycles and variation in sea-level, temperature and effective moisture. The concept that sand dunes have a wind memory and represent a record of the wind that blew to produce them can be modified and applied to dunefields: the morphology of dunefields represents an environmental record, going back thousands of years. The carbonate content of eastern Cape coastal sands is biogenic with young coarse carbonate grains constantly being added to the system, resulting in a pronounced negative correlation of radiocarbon age with grain size. It takes thousands of years for an average mollusc shell to be broken to 1-mm-diameter fragments, and a further couple of thousand years to break these sizes down to 0.2-0.3 mm diameter. Eastern Cape coastal dunefields have for the first time been dated definitively via the radiocarbon ages of the carbonate component of the sand. These dunefields have been forming during the past 5000 years or so. Dating wind-blown sand transport is feasible, and correlates with dates inferred from the dunefield morphology. 5 figs., 1 tab., 18 refs

  14. Temporal and spatial variation of groundwater in quantity and quality in sand dune at coastal region, Kamisu city, central Japan.

    Science.gov (United States)

    Umei, Yohei; Tsujimura, Maki; Sakakibara, Koichi; Watanabe, Yasuto; Minema, Motomitsu

    2016-04-01

    The role of groundwater in integrated water management has become important in recent 10 years, though the surface water is the major source of drinking water in Japan. Especially, it is remarked that groundwater recharge changed due to land cover change under the anthropogenic and climatic condition factors. Therefore, we need to investigate temporal and spatial variation of groundwater in quantity and quality focusing on the change during recent 10-20 years in specific region. We performed research on groundwater level and quality in sand dune at coastal region facing Pacific Ocean, Kamisu city, Ibaraki Prefecture, which have been facing environmental issues, such as land cover change due to soil mining for construction and urbanization. We compared the present situation of groundwater with that in 2000 using existed data to clarify the change of groundwater from 2000 to 2015. The quality of water is dominantly characterized by Ca2+-HCO3- in both 2000 and 2015, and nitrate was not observed in 2015, though it was detected in some locations in 2000. This may be caused by improvement of the domestic wastewater treatment. The topography of groundwater table was in parallel with that of ground surface in 2015, same as that in 2000. However, a depletion of groundwater table was observed in higher elevation area in 2015 as compared with that in 2000, and this area corresponds to the locations where the land cover has changed due to soil mining and urbanization between 2015 and 2000. In the region of soil mining, the original soil is generally replaced by impermeable soil after mining, and this may cause a decrease of percolation and net groundwater recharge, thus the depletion of groundwater table occurred after the soil mining.

  15. Patterns and processes influencing helminth parasites of Arctic coastal communities during climate change.

    Science.gov (United States)

    Galaktionov, K V

    2017-07-01

    This review analyses the scarce available data on biodiversity and transmission of helminths in Arctic coastal ecosystems and the potential impact of climate changes on them. The focus is on the helminths of seabirds, dominant parasites in coastal ecosystems. Their fauna in the Arctic is depauperate because of the lack of suitable intermediate hosts and unfavourable conditions for species with free-living larvae. An increasing proportion of crustaceans in the diet of Arctic seabirds would result in a higher infection intensity of cestodes and acanthocephalans, and may also promote the infection of seabirds with non-specific helminths. In this way, the latter may find favourable conditions for colonization of new hosts. Climate changes may alter the composition of the helminth fauna, their infection levels in hosts and ways of transmission in coastal communities. Immigration of boreal invertebrates and fish into Arctic seas may allow the circulation of helminths using them as intermediate hosts. Changing migratory routes of animals would alter the distribution of their parasites, facilitating, in particular, their trans-Arctic transfer. Prolongation of the seasonal 'transmission window' may increase the parasitic load on host populations. Changes in Arctic marine food webs would have an overriding influence on the helminths' circulation. This process may be influenced by the predicted decreased of salinity in Arctic seas, increased storm activity, coastal erosion, ocean acidification, decline of Arctic ice, etc. Greater parasitological research efforts are needed to assess the influence of factors related to Arctic climate change on the transmission of helminths.

  16. Coastal terrorism: using tabletop discussions to enhance coastal community infrastructure through relationship building.

    Science.gov (United States)

    Richter, Jane; Livet, Melanie; Stewart, Jill; Feigley, Charles E; Scott, Geoff; Richter, Donna L

    2005-11-01

    The unique vulnerability of the nation's ports to terrorist attacks and other major disasters requires development of specialized training approaches that integrate and connect critical stakeholders. In 2003, the University of South Carolina Center for Public Health Preparedness developed and held its first Coastal Terrorism workshop in conjunction with the National Oceanic and Atmospheric Administration. Key federal, regional, state, and coastal agency leaders were invited to the 2-day event to explore, in a no-risk environment, the crucial role that public health agencies would play in a covert biological agent incident aboard a cruise ship. The incident began as a possible outbreak of a Norwalk-like viral agent; however, as the scenario unfolded, evidence of a terrorist plot emerged. This immediately shifted the scenario from a public health-dominated incident to one directed by law enforcement. Communication and coordination issues surfaced illustrating potential conflicts between disciplines and jurisdictions in terms of roles and responsibilities of responding agencies. The goals of the workshop were to facilitate communication and interagency networking among coastal stakeholders while assessing their training and research needs and increasing their familiarity with resources and protocols regarding a bioterrorist coastal event. Positive systems changes were observed.

  17. Influence of salinity on bacterioplankton communities from the Brazilian rain forest to the coastal Atlantic Ocean.

    Science.gov (United States)

    Silveira, Cynthia B; Vieira, Ricardo P; Cardoso, Alexander M; Paranhos, Rodolfo; Albano, Rodolpho M; Martins, Orlando B

    2011-03-09

    Planktonic bacteria are recognized as important drivers of biogeochemical processes in all aquatic ecosystems, however, the taxa that make up these communities are poorly known. The aim of this study was to investigate bacterial communities in aquatic ecosystems at Ilha Grande, Rio de Janeiro, Brazil, a preserved insular environment of the Atlantic rain forest and how they correlate with a salinity gradient going from terrestrial aquatic habitats to the coastal Atlantic Ocean. We analyzed chemical and microbiological parameters of water samples and constructed 16S rRNA gene libraries of free living bacteria obtained at three marine (two coastal and one offshore) and three freshwater (water spring, river, and mangrove) environments. A total of 836 sequences were analyzed by MOTHUR, yielding 269 freshwater and 219 marine operational taxonomic units (OTUs) grouped at 97% stringency. Richness and diversity indexes indicated that freshwater environments were the most diverse, especially the water spring. The main bacterial group in freshwater environments was Betaproteobacteria (43.5%), whereas Cyanobacteria (30.5%), Alphaproteobacteria (25.5%), and Gammaproteobacteria (26.3%) dominated the marine ones. Venn diagram showed no overlap between marine and freshwater OTUs at 97% stringency. LIBSHUFF statistics and PCA analysis revealed marked differences between the freshwater and marine libraries suggesting the importance of salinity as a driver of community composition in this habitat. The phylogenetic analysis of marine and freshwater libraries showed that the differences in community composition are consistent. Our data supports the notion that a divergent evolutionary scenario is driving community composition in the studied habitats. This work also improves the comprehension of microbial community dynamics in tropical waters and how they are structured in relation to physicochemical parameters. Furthermore, this paper reveals for the first time the pristine

  18. Influence of salinity on bacterioplankton communities from the Brazilian rain forest to the coastal Atlantic Ocean.

    Directory of Open Access Journals (Sweden)

    Cynthia B Silveira

    Full Text Available BACKGROUND: Planktonic bacteria are recognized as important drivers of biogeochemical processes in all aquatic ecosystems, however, the taxa that make up these communities are poorly known. The aim of this study was to investigate bacterial communities in aquatic ecosystems at Ilha Grande, Rio de Janeiro, Brazil, a preserved insular environment of the Atlantic rain forest and how they correlate with a salinity gradient going from terrestrial aquatic habitats to the coastal Atlantic Ocean. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed chemical and microbiological parameters of water samples and constructed 16S rRNA gene libraries of free living bacteria obtained at three marine (two coastal and one offshore and three freshwater (water spring, river, and mangrove environments. A total of 836 sequences were analyzed by MOTHUR, yielding 269 freshwater and 219 marine operational taxonomic units (OTUs grouped at 97% stringency. Richness and diversity indexes indicated that freshwater environments were the most diverse, especially the water spring. The main bacterial group in freshwater environments was Betaproteobacteria (43.5%, whereas Cyanobacteria (30.5%, Alphaproteobacteria (25.5%, and Gammaproteobacteria (26.3% dominated the marine ones. Venn diagram showed no overlap between marine and freshwater OTUs at 97% stringency. LIBSHUFF statistics and PCA analysis revealed marked differences between the freshwater and marine libraries suggesting the importance of salinity as a driver of community composition in this habitat. The phylogenetic analysis of marine and freshwater libraries showed that the differences in community composition are consistent. CONCLUSIONS/SIGNIFICANCE: Our data supports the notion that a divergent evolutionary scenario is driving community composition in the studied habitats. This work also improves the comprehension of microbial community dynamics in tropical waters and how they are structured in relation to physicochemical

  19. Influence of Salinity on Bacterioplankton Communities from the Brazilian Rain Forest to the Coastal Atlantic Ocean

    Science.gov (United States)

    Silveira, Cynthia B.; Vieira, Ricardo P.; Cardoso, Alexander M.; Paranhos, Rodolfo; Albano, Rodolpho M.; Martins, Orlando B.

    2011-01-01

    Background Planktonic bacteria are recognized as important drivers of biogeochemical processes in all aquatic ecosystems, however, the taxa that make up these communities are poorly known. The aim of this study was to investigate bacterial communities in aquatic ecosystems at Ilha Grande, Rio de Janeiro, Brazil, a preserved insular environment of the Atlantic rain forest and how they correlate with a salinity gradient going from terrestrial aquatic habitats to the coastal Atlantic Ocean. Methodology/Principal Findings We analyzed chemical and microbiological parameters of water samples and constructed 16S rRNA gene libraries of free living bacteria obtained at three marine (two coastal and one offshore) and three freshwater (water spring, river, and mangrove) environments. A total of 836 sequences were analyzed by MOTHUR, yielding 269 freshwater and 219 marine operational taxonomic units (OTUs) grouped at 97% stringency. Richness and diversity indexes indicated that freshwater environments were the most diverse, especially the water spring. The main bacterial group in freshwater environments was Betaproteobacteria (43.5%), whereas Cyanobacteria (30.5%), Alphaproteobacteria (25.5%), and Gammaproteobacteria (26.3%) dominated the marine ones. Venn diagram showed no overlap between marine and freshwater OTUs at 97% stringency. LIBSHUFF statistics and PCA analysis revealed marked differences between the freshwater and marine libraries suggesting the importance of salinity as a driver of community composition in this habitat. The phylogenetic analysis of marine and freshwater libraries showed that the differences in community composition are consistent. Conclusions/Significance Our data supports the notion that a divergent evolutionary scenario is driving community composition in the studied habitats. This work also improves the comprehension of microbial community dynamics in tropical waters and how they are structured in relation to physicochemical parameters

  20. Distribution, Community Composition, and Potential Metabolic Activity of Bacterioplankton in an Urbanized Mediterranean Sea Coastal Zone.

    Science.gov (United States)

    Richa, Kumari; Balestra, Cecilia; Piredda, Roberta; Benes, Vladimir; Borra, Marco; Passarelli, Augusto; Margiotta, Francesca; Saggiomo, Maria; Biffali, Elio; Sanges, Remo; Scanlan, David J; Casotti, Raffaella

    2017-09-01

    Bacterioplankton are fundamental components of marine ecosystems and influence the entire biosphere by contributing to the global biogeochemical cycles of key elements. Yet, there is a significant gap in knowledge about their diversity and specific activities, as well as environmental factors that shape their community composition and function. Here, the distribution and diversity of surface bacterioplankton along the coastline of the Gulf of Naples (GON; Italy) were investigated using flow cytometry coupled with high-throughput sequencing of the 16S rRNA gene. Heterotrophic bacteria numerically dominated the bacterioplankton and comprised mainly Alphaproteobacteria , Gammaproteobacteria , and Bacteroidetes Distinct communities occupied river-influenced, coastal, and offshore sites, as indicated by Bray-Curtis dissimilarity, distance metric (UniFrac), linear discriminant analysis effect size (LEfSe), and multivariate analyses. The heterogeneity in diversity and community composition was mainly due to salinity and changes in environmental conditions across sites, as defined by nutrient and chlorophyll a concentrations. Bacterioplankton communities were composed of a few dominant taxa and a large proportion (92%) of rare taxa (here defined as operational taxonomic units [OTUs] accounting for coastal zones is of critical importance, considering that these areas are highly productive and anthropogenically impacted. Their richness and evenness, as well as their potential activity, are very important to assess ecosystem health and functioning. Here, we investigated bacterial distribution, community composition, and potential metabolic activity in the GON, which is an ideal test site due to its heterogeneous environment characterized by a complex hydrodynamics and terrestrial inputs of varied quantities and quality. Our study demonstrates that bacterioplankton communities in this region are highly diverse and strongly regulated by a combination of different environmental

  1. Quantitative isotope incorporation reveals substrate partitioning in a coastal microbial community.

    Science.gov (United States)

    Mayali, Xavier; Weber, Peter K

    2018-05-01

    To quantitatively link microbial identity with biogeochemical function, we carried out 14 simultaneous stable isotope probing experiments with organic and inorganic C and N substrates to measure the isotope incorporation by over one hundred co-occurring eukaryotic and prokaryotic populations in a coastal community. We found that nitrate was the most commonly incorporated substrate, and that light-driven carbon fixation was carried out by some bacterial taxa from the Flavobacteriales and OM60 (NOR5) clade, in addition to photoautotrophic phytoplankton. We found that organisms that incorporated starch, maltose, glucose, lactose and bicarbonate were phylogenetically clustered, suggesting that specific bacterial lineages specialized in the incorporation of these substrates. The data further revealed that coastal microorganisms spanned a range of resource utilization strategies from generalists to specialists and demonstrated a high level of substrate partitioning, with two thirds of taxa exhibiting unique substrate incorporation patterns and the remaining third shared by no more than three OTUs each. Specialists exhibited more extreme incorporation levels (high or low), whereas generalists displayed more intermediate activity levels. These results shed valuable insights into the bottom-up ecological strategies enabling the persistence of high microbial diversity in aquatic ecosystems.

  2. Turbulent Reynolds stress and quadrant event activity in wind flow over a coastal foredune

    Science.gov (United States)

    Chapman, Connie A.; Walker, Ian J.; Hesp, Patrick A.; Bauer, Bernard O.; Davidson-Arnott, Robin G. D.

    2012-05-01

    Recent research on quasi-instantaneous turbulent kinematic Reynolds stresses (RS, - u'w') and decomposed quadrant event activity (e.g., ejections and sweeps) over dunes in fluvial settings and in wind tunnels has shown that turbulent stresses at the toe of a dune often exceed time-averaged, streamwise shear stress (ρ u * 2) estimates. It is believed that semi-coherent turbulent structures are conveyed toward the bed along concave streamlines in this region and that impact of these structures cause fluctuations in local surface stresses that assist in grain entrainment. This has been hypothesized to explain how sand is supplied to the windward slope through a region of flow stagnation. Toward the crest, surface stress increases and becomes dominated by streamwise accelerations resulting from streamline compression and convexity that suppress vertical motions. High-frequency (32 Hz) measurements of turbulent wind flow from 3-D ultrasonic anemometers are analyzed for oblique onshore flow over a vegetated coastal foredune in Prince Edward Island, Canada. Reynolds stress and quadrant activity distributions varied with height (0.60 m and 1.66 m) and location over the dune. In general, quadrant 2 ejection (u' 0) and quadrant 4 sweep activity (u' > 0, w' 0, w' > 0) and quadrant 3 inward interaction (u' dune and may help to explain sand transport potential and dune maintenance. For example, areas with a high frequency of ejection and sweep activity may have higher rates of sediment entrainment and transport, whereas areas with lower ejection and sweep activity and an increase in outward and inward interactions, which contribute negatively to Reynolds stress generation, may experience a greater potential for deposition. Further research on associations between quadrant event activity and coincident sand transport is required to confirm this hypothesis and the resultant significance of the flow exuberance effect in aeolian dune morphodynamics.

  3. Characteristics of dune-paleosol-sequences in Fuerteventura. - What should be questioned?

    Science.gov (United States)

    Faust, Dominik; Willkommen, Tobias; Yanes, Yurena; Richter, David; Zöller, Ludwig

    2013-04-01

    Characteristics of dune-paleosol-sequences in Fuerteventura. - What should be questioned? Dominik Faust, TU Dresden, Germany Tobias Willkommen, TU Dresden, Germany Yurena Yanes, CSIC Granada/Cincinatti, Spain/USA David Richter, TU Dresden, Germany Ludwig Zöller, Uni Bayreuth, Germany The northern part of Fuerteventura is characterized by large dune fields. We investigated dune-paleosol-sequences in four pits to establish a robust stratigraphy and to propose a standard section. An interaction of processes like dune formation, soil formation and redeposition of soils and sand are most important to understand the principles of landscape development in the study area. To our mind a process cycle seem to be important: First climbing-dunes are formed by sand of shelf origin. Then soil formation could have taken place. Soil and/or sand were then eroded and deposited at toe slope position. This material in turn is the source of new sand supply and dune formation. The described cycle may be repeated several times and this ping-pong-process holds on. The results are sections composed of dune layers, paleosols and colluvial material interbedded. Fundamental questions still remain unanswered: Is climate change responsable for changes in process combination (e.g. from dune formation to soil formation)? Or are these features due to divergence phenomenon, where different effects/results (dune and soils) may be linked to similar causes (here: climate)? Assuming that different features (soils and dunes) were formed under one climate, increasing soil forming intensity could be mainly a function of decreasing sand supply. This in turn could be caused by reduced sand production (s. ZECH et al. accepted). However geochemical data and mollusc assemblages point to changing environments in space and even climate modifications in time.

  4. Planetary dune workshop expands to include subaqueous processes

    Science.gov (United States)

    Titus, Timothy N.; Bryant, Gerald; Rubin, David M.

    2018-01-01

    Dune-like structures appear in the depths of Earth’s oceans, across its landscapes, and in the extremities of the solar system beyond. Dunes rise up under the thick dense atmosphere of Venus, and they have been found under the almost unimaginably ephemeral atmosphere of a comet.

  5. Macroalgal-dominated coastal detritic communities from the Western Mediterranean and the Northeastern Atlantic

    Directory of Open Access Journals (Sweden)

    S. JOHER

    2016-07-01

    Full Text Available This is a qualitative comparison of the distribution of macroalgal-dominated coastal detritic communities from the Western Mediterranean and the Northeastern Atlantic, based on our own data from the Balearic Islands (Western Mediterranean and available data from literature. The macroalgal-dominated coastal detritic bottoms from both regions could be distinguished by the presence of a high number of regional exclusive non-carbonated species, and the presence of a high number of maërl-forming species in the Mediterranean. Further, regional differences in the distribution of some exclusive species allowed the distinction of three zones in the Northeastern Atlantic (United Kingdom, French Brittany and Galicia, while no differences were found within the Western Mediterranean. However, the algal communities considered in the selected literature could not be qualitatively distinguished, and all the samples should be considered as maërl beds. Lithothamnion corallioides and Phymatolithon calcareum were the most widespread maërl forming species in the two regions, while in the Western Mediterranean Spongites fruticulosus was also very frequent. According to the differences in the species composition of the basal and erect strata of these beds, and also in their species richness, five different morphologies of macroalgal-dominated detritic bottoms could be distinguished. Their main characteristic species and their biogeographical distribution are detailed.

  6. Restoring Myanmar’s mangrove forests and coastal communities’ socioeconomic stability with community based mangrove management

    OpenAIRE

    Lindholt, Jonathan Grevstad

    2016-01-01

    Mangrove forests have a significant capacity to provide ecosystem services. However, deforestation from land use changes has led to widespread degradation of these services and consequently jeopardizes coastal populations. Reforestation projects and attempts to develop sustainable management procedures are widely attempted worldwide. However, these projects often have sustainable rural livelihood improvements as a complementary goal. Integrated approaches such as Community Based Mangrove Mana...

  7. Differences in mycorrhizal communities between Epipactis palustris, E. helleborine and its presumed sister species E. neerlandica.

    Science.gov (United States)

    Jacquemyn, Hans; Waud, Michael; Lievens, Bart; Brys, Rein

    2016-07-01

    In orchid species that have populations occurring in strongly contrasting habitats, mycorrhizal divergence and other habitat-specific adaptations may lead to the formation of reproductively isolated taxa and ultimately to species formation. However, little is known about the mycorrhizal communities associated with recently diverged sister taxa that occupy different habitats. In this study, 454 amplicon pyrosequencing was used to investigate mycorrhizal communities associating with Epipactis helleborine in its typical forest habitat and with its presumed sister species E. neerlandica that almost exclusively occurs in coastal dune habitats. Samples of the phylogenetically more distant E. palustris, which co-occurred with E. neerlandica, were also included to investigate the role of habitat-specific conditions on mycorrhizal communities. A total of 105 operational taxonomic units (OTUs) of putative orchid mycorrhizal fungi were observed in the three studied species. The majority of these fungi were endophytic fungi of Helotiales and ectomycorrhizal fungi belonging to Thelephoraceae, Sebacinaceae and Inocybaceae. In addition, a large number of other ectomycorrhizal taxa were detected, including Cortinarius, Cenococcum, Tuber, Geopora, Wilcoxina, Meliniomyces, Hebeloma, Tricholoma, Russula and Peziza Mycorrhizal communities differed significantly between the three species, but differences were most pronounced between the forest species (E. helleborine) and the two dune slack species (E. neerlandica and E. palustris). The results clearly showed that recently diverged orchid species that occupy different habitats were characterized by significantly different mycorrhizal communities and call for more detailed experiments that aim at elucidating the contribution of habitat-specific adaptations in general and mycorrhizal divergence in particular to the process of speciation in orchids. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany

  8. TUMEUR ORBITAIRE: MANIFESTATION INITIALE D'UNE MALADIE ...

    African Journals Online (AJOL)

    L'hétérogénéité et la rareté des formes multicentriques de la maladie de Castleman font que leurs traitements soient très disparates. La maladie de Castleman doit être considérée comme un diagnostic possible d'une adénopathie cervicale particulièrement chez les patients souffrant d'une maladie inflammatoire chronique.

  9. Dune Erosion Models and Swash Zone Kinematics from Remote Video Observations

    Science.gov (United States)

    2010-12-09

    system. Thus, successful prediction of dune erosion requires knowledge of the expected trajectory of the eroding dune toe . If we describe the... dune toe trajectory as following a slope, βT, two end member retreat trajectories exist. The first would be direct landward erosion so that zb never...changes     0 0   T bb ztz  (2.24) The second end member trajectory is that erosion moves the dune toe directly up the foreshore slope

  10. Environmental filtering drives the shape and breadth of the seed germination niche in coastal plant communities.

    Science.gov (United States)

    Fernández-Pascual, Eduardo; Pérez-Arcoiza, Adrián; Prieto, José Alberto; Díaz, Tomás E

    2017-05-01

    A phylogenetic comparative analysis of the seed germination niche was conducted in coastal plant communities of western Europe. Two hypotheses were tested, that (1) the germination niche shape (i.e. the preference for a set of germination cues as opposed to another) would differ between beaches and cliffs to prevent seedling emergence in the less favourable season (winter and summer, respectively); and (2) the germination niche breadth (i.e. the amplitude of germination cues) would be narrower in the seawards communities, where environmental filtering is stronger. Seeds of 30 specialist species of coastal plant communities were collected in natural populations of northern Spain. Their germination was measured in six laboratory treatments based on field temperatures. Germination niche shape was estimated as the best germination temperature. Germination niche breadth was calculated using Pielou's evenness index. Differences between plant communities in their germination niche shape and breadth were tested using phylogenetic generalized least squares regression (PGLS). Germination niche shape differed between communities, being warm-cued in beaches (best germination temperature = 20 °C) and cold-cued in cliffs (14 °C). Germination niche was narrowest in seawards beaches (Pielou's index = 0·89) and broadest in landwards beaches (0·99). Cliffs had an intermediate germination niche breadth (0·95). The relationship between niche and plant community had a positive phylogenetic signal for shape (Pagel's λ = 0·64) and a negative one for breadth (Pagel's λ = -1·71). Environmental filters shape the germination niche to prevent emergence in the season of highest threat for seedling establishment. The germination niche breadth is narrower in the communities with stronger environmental filters, but only in beaches. This study provides empirical support to a community-level generalization of the hypotheses about the environmental drivers of the germination

  11. Shifts in coastal sediment oxygenation cause pronounced changes in microbial community composition and associated metabolism.

    Science.gov (United States)

    Broman, Elias; Sjöstedt, Johanna; Pinhassi, Jarone; Dopson, Mark

    2017-08-09

    A key characteristic of eutrophication in coastal seas is the expansion of hypoxic bottom waters, often referred to as 'dead zones'. One proposed remediation strategy for coastal dead zones in the Baltic Sea is to mix the water column using pump stations, circulating oxygenated water to the sea bottom. Although microbial metabolism in the sediment surface is recognized as key in regulating bulk chemical fluxes, it remains unknown how the microbial community and its metabolic processes are influenced by shifts in oxygen availability. Here, coastal Baltic Sea sediments sampled from oxic and anoxic sites, plus an intermediate area subjected to episodic oxygenation, were experimentally exposed to oxygen shifts. Chemical, 16S rRNA gene, metagenomic, and metatranscriptomic analyses were conducted to investigate changes in chemistry fluxes, microbial community structure, and metabolic functions in the sediment surface. Compared to anoxic controls, oxygenation of anoxic sediment resulted in a proliferation of bacterial populations in the facultative anaerobic genus Sulfurovum that are capable of oxidizing toxic sulfide. Furthermore, the oxygenated sediment had higher amounts of RNA transcripts annotated as sqr, fccB, and dsrA involved in sulfide oxidation. In addition, the importance of cryptic sulfur cycling was highlighted by the oxidative genes listed above as well as dsvA, ttrB, dmsA, and ddhAB that encode reductive processes being identified in anoxic and intermediate sediments turned oxic. In particular, the intermediate site sediments responded differently upon oxygenation compared to the anoxic and oxic site sediments. This included a microbial community composition with more habitat generalists, lower amounts of RNA transcripts attributed to methane oxidation, and a reduced rate of organic matter degradation. These novel data emphasize that genetic expression analyses has the power to identify key molecular mechanisms that regulate microbial community responses

  12. Desalination impacts on the coastal environment: Ash Shuqayq, Saudi Arabia

    International Nuclear Information System (INIS)

    Alharbi, O.A.; Phillips, M.R.; Williams, A.T.; Gheith, A.M.; Bantan, R.A.; Rasul, N.M.

    2012-01-01

    Ash Shuqayq (Saudi Red Sea coast) is approximately 28 km long and characterised by narrow rocky headlands with intermittent pocket beaches. Fifty-two sediment samples from six different environments (beach, dune, sabkha, tidal/lagoon, offshore and wadi) were analysed. Testing showed that beach and dune sands are mainly medium to fine grained, with some very coarse sand (MZ = − 0.59ø). Both beach and dune sands are moderately well to moderately sorted, although some are poorly sorted due to an influx of wadi sediments. Sediment source together with littoral reworking contributed to grain size variation. Carbonate content varied between 1.5% and 23%, whilst the organic content varied between 1.1% and 13%. Spatial analysis showed increasing southward carbonate and organic content, with both correlated (r = 0.57). Sabkha sediments had significantly higher carbonate percentages (t = 2.898; df = 18; p < 0.01) and results suggested origins are similar for both UAE Arabian Sea and Saudi Arabian Red Sea coasts. X-ray diffractions show beach and dune sediments are mainly composed of detrital quartz and plagioclase feldspar with uncommon amounts of chlorites. Analysis of sediment characteristics, composition and shoreline distribution alongside coastal processes, indicate that high chlorite levels are probably caused by desalination processes. Due to human and ecosystem health consequences and the likely increased demand for desalination plants, similar analyses should be undertaken elsewhere, e.g. the Mediterranean. - Highlights: ► New and previously unpublished Red Sea sediment information. ► Sediment chemical and spatial variations established. ► Sabkha origins are similar for both UAE Arabian Sea and Saudi Arabian Red Sea coasts. ► Desalination plant shown as cause of increased marine sediment chlorite levels.

  13. Assessing sea-level rise impact on saltwater intrusion into the root zone of a geo-typical area in coastal east-central Florida.

    Science.gov (United States)

    Xiao, Han; Wang, Dingbao; Medeiros, Stephen C; Hagen, Scott C; Hall, Carlton R

    2018-07-15

    Saltwater intrusion (SWI) into root zone in low-lying coastal areas can affect the survival and spatial distribution of various vegetation species by altering plant communities and the wildlife habitats they support. In this study, a baseline model was developed based on FEMWATER to simulate the monthly variation of root zone salinity of a geo-typical area located at the Cape Canaveral Barrier Island Complex (CCBIC) of coastal east-central Florida (USA) in 2010. Based on the developed and calibrated baseline model, three diagnostic FEMWATER models were developed to predict the extent of SWI into root zone by modifying the boundary values representing the rising sea level based on various sea-level rise (SLR) scenarios projected for 2080. The simulation results indicated that the extent of SWI would be insignificant if SLR is either low (23.4cm) or intermediate (59.0cm), but would be significant if SLR is high (119.5cm) in that infiltration/diffusion of overtopping seawater in coastal low-lying areas can greatly increase root zone salinity level, since the sand dunes may fail to prevent the landward migration of seawater because the waves of the rising sea level can reach and pass over the crest under high (119.5cm) SLR scenario. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Developing New Strategies for Coping with Weather: Work in Alaskan and Canadian Coastal Communities

    Science.gov (United States)

    Atkinson, D. E.

    2014-12-01

    A changing climate is manifested at ground level through the day to day weather. For all Northern residents - community, industrial, operational and response - the need to think about the weather is ever present. Northern residents, and in particular, indigenous community residents, fully understand implications of the weather, however, a comment that has been heard more often is that old ways of knowing are not as reliable as they once were. Weather patterns seem less consistent and subject to more rapid fluctuations. Compromised traditional ways of knowing puts those who need to travel or hunt at greater risk. One response to adapt to this emerging reality is to make greater use of western sources of information, such as weather data and charts provided by NOAA's National Weather Service or Environment Canada. The federal weather agencies have very large and complex forecasting regions to cover, and so one problem is that it can be difficult to provide perfectly tailored forecasts, that cover all possible problems, right down to the very local scale in the communities. Only those affected have a complete feel for their own concerns. Thus, key to a strategy to improve the utility of available weather information is a linking of local-scale manifestations of problematic weather to the larger-scale weather patterns. This is done in two ways: by direct consultation with Northern residents, and by installation of equipment to measure parameters of interest to residents, which are not already being measured. This talk will overview projects in coastal Alaska and Canada targeting this objective. The challenge of designing and conducting interviews, and then of harvesting relevant information, will be visited using examples from the three major contexts: coastal community, industrial, and operational. Examples of how local comments can be married to weather products will be presented.

  15. Holocene beach buildup and coastal aeolian sand incursions off the Nile littoral cell

    Science.gov (United States)

    Roskin, Joel; Sivan, Dorit; Shtienberg, Gilad; Porat, Naomi; Bookman, Revital

    2017-04-01

    Israel's coastal plain is abundant with sand originating from the Nile littoral cell. The inland windblown loose sand has formed 3-6 km wide lobe-like sand and dune fields currently comprised of foredunes, linear and northeasterly facing transverse and parabolic dunes that are currently stabilized by vegetation. This study reviews the architecture and history of the these dune fields aiming to: (a) Date the timings of beach accretion, and sand and dune incursions. (b) Discriminate between natural and human-induced forcing factors of sand mobilization and stabilization in time and space. (c) Present a model of the dunescape development. (d) Assess scenarios of sand transport in the future charcaterized by intense human impact and climate change. Luminescence ages, radiocarbon dates and relative ages from previously published geological and archaeological reports, historical texts, together with new optically stimulated luminescence (OSL) ages and stratigraphic and sedimentological data are analyzed. The deposition, mobilizations and preservation of the sand bodies, initially induced by the decline in sea level rise at 6-4 ka, were later controlled by historic land-use intensity and modern land-use/negligence practices. At 6 ka, beach sand buildup rapidly started. Where aeolianite ridges bordered the coast, pulses of sand with biogenic carbonate grains unconformably draped the ridges and rapidly consolidated into a distinct sandy calcarenite unit. Further east, sand sheets and low dunes partly pedogenized following their incursion, but did not cement. The water retention capacities of the sand sheets enabled the establishment of a sand-stabilizing vegetation cover that probably became an attractive environment for fuel and grazing. The growing Hellenistic-Roman-Byzantine ( 2.4-1.3 ka) populations probably led to increased consumption and massive destruction of sand stabilizing vegetation, enabling sand erodibility and mobilization during winter storms. The sand

  16. Deep learning for the detection of barchan dunes in satellite images

    Science.gov (United States)

    Azzaoui, A. M.; Adnani, M.; Elbelrhiti, H.; Chaouki, B. E. K.; Masmoudi, L.

    2017-12-01

    Barchan dunes are known to be the fastest moving sand dunes in deserts as they form under unidirectional winds and limited sand supply over a firm coherent basement (Elbelrhiti and Hargitai,2015). They were studied in the context of natural hazard monitoring as they could be a threat to human activities and infrastructures. Also, they were studied as a natural phenomenon occurring in other planetary landforms such as Mars or Venus (Bourke et al., 2010). Our region of interest was located in a desert region in the south of Morocco, in a barchan dunes corridor next to the town of Tarfaya. This region which is part of the Sahara desert contained thousands of barchans; which limits the number of dunes that could be studied during field missions. Therefore, we chose to monitor barchan dunes with satellite imagery, which can be seen as a complementary approach to field missions. We collected data from the Sentinel platform (https://scihub.copernicus.eu/dhus/); we used a machine learning method as a basis for the detection of barchan dunes positions in the satellite image. We trained a deep learning model on a mid-sized dataset that contained blocks representing images of barchan dunes, and images of other desert features, that we collected by cropping and annotating the source image. During testing, we browsed the satellite image with a gliding window that evaluated each block, and then produced a probability map. Finally, a threshold on the latter map exposed the location of barchan dunes. We used a subsample of data to train the model and we gradually incremented the size of the training set to get finer results and avoid over fitting. The positions of barchan dunes were successfully detected and deep learning was an effective method for this application. Sentinel-2 images were chosen for their availability and good temporal resolution, which will allow the tracking of barchan dunes in future work. While Sentinel images had sufficient spatial resolution for the

  17. Characterization and dating of coastal deposits of NW Portugal (Minho-Neiva area): A record of climate, eustasy and crustal uplift during the Quaternary

    DEFF Research Database (Denmark)

    Carvalhido, Ricardo P.; Pereira, Diamantino I.; Cunha, Pedro P.

    2014-01-01

    This study presents the characterization and numerical dating of Quaternary coastal deposits of NW Portugal, located between the mouths of the Minho and Neiva rivers. They record continental (small alluvial fans and streams) and transitional (aeolian dunes, interdune ponds, estuary, sandy...... and gravelly beaches) paleoenvironments. Quartz and K-feldspar optically stimulated luminescence (OSL) dating is employed as well as AMS C-14 dating. A staircase of coastal terraces (abrasion shore platforms) was identified (altimetry, a.s.l.) and ascribed to the following probable Marine Isotope Stages (MIS...

  18. Impact of human interventions and coastal processes along the Nile Delta coast, Egypt during the past

    Directory of Open Access Journals (Sweden)

    Elham M. Ali

    2016-03-01

    Full Text Available The coastal zone of the Nile Delta lodges highly populated cities (e.g. Alexandria, Port Said together with small towns and villages. It represents the major industrial, agricultural, and economic resource of the country. The area has been subjected to extensive and excessive unplanned developmental projects to foster the economic status of the local communities that, however, negatively impacted both land use and land cover characteristics. Satellite images were processed to identify the dominant land use/cover classes (from 1990 to 2014 and GIS techniques spatially analyzed and quantified the rate of changes. Five dominant classes were identified and their changes monitored against the unprecedented human activities. Results demonstrated a significant rate of land forms transformation within the last 25 years, in favor of developing of fish farming (+13% and urban (+22%. Such development of these land use classes was unfortunately at the expense of the agricultural land (−15%, coastal dune and barren land (−13% and water bodies (−7%. In addition, the coastal processes have made significant changes in the shoreline creating areas of erosion (maximum of 24–36 m/year and others of accretion (a total accreted area of 3.14 km2 with an overall retreat of 2.7 km2 along the shoreline. The expected changes in climate and sea level rise will worsen the erosion rate and the general status of the coastal zone. Based on the IPCC scenarios (i.e. the 59 cm sea level rise by the end of this century and the proposed land subsidence (2.5 mm/year, one fifth of the Nile Delta will be seriously vulnerable to inundation.

  19. The influence of coastal morphology on wind dynamics

    Directory of Open Access Journals (Sweden)

    Darius Jarmalavičius

    2012-05-01

    Full Text Available An analysis of the dynamics of wind velocity along the Baltic coast of Lithuania is presented, based on data collected during field experiments in the summer, fall and winter of 1999–2001 and 2007–2009 at several sites (Būtingė, Šaipiai, Smiltynė, Juodkrantė, Pervalka and Nida. The locations were chosen in order to encompass a wide spectrum of beach and dune ridge morphology. The relationship between wind velocity dynamics and coastal morphology was established, based on measurements of the slope angle, height and shape of the dune crest, as well as measurements of the morphology of the area behind the foredune ridge. On the basis of a comparison of near-surface wind velocity patterns, shear velocity (U* and surface roughness length (z0 were calculated. It was determined that U* decreases from the middle of the beach towards the foredune toe, then increases towards the crest of the foredune and decreases down the lee slope. A direct correlation exists between U* and the stoss slope inclination, and the relative height of the foredune. Surface roughness length also increases from the beach towards the foredune crest.

  20. Sediment bacterial community structures and their predicted functions implied the impacts from natural processes and anthropogenic activities in coastal area.

    Science.gov (United States)

    Su, Zhiguo; Dai, Tianjiao; Tang, Yushi; Tao, Yile; Huang, Bei; Mu, Qinglin; Wen, Donghui

    2018-06-01

    Coastal ecosystem structures and functions are changing under natural and anthropogenic influences. In this study, surface sediment samples were collected from disturbed zone (DZ), near estuary zone (NEZ), and far estuary zone (FEZ) of Hangzhou Bay, one of the most seriously polluted bays in China. The bacterial community structures and predicted functions varied significantly in different zones. Firmicutes were found most abundantly in DZ, highlighting the impacts of anthropogenic activities. Sediment total phosphorus was most influential on the bacterial community structures. Predicted by PICRUSt analysis, DZ significantly exceeded FEZ and NEZ in the subcategory of Xenobiotics Biodegradation and Metabolism; and DZ enriched all the nitrate reduction related genes, except nrfA gene. Seawater salinity and inorganic nitrogen, respectively as the representative natural and anthropogenic factor, performed exact-oppositely in nitrogen metabolism functions. The changes of bacterial community compositions and predicted functions provide a new insight into human-induced pollution impacts on coastal ecosystem. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Environmental drivers of heterogeneity in the trophic-functional structure of protozoan communities during an annual cycle in a coastal ecosystem.

    Science.gov (United States)

    Xu, Guangjian; Yang, Eun Jin; Xu, Henglong

    2017-08-15

    Trophic-functional groupings are an important biological trait to summarize community structure in functional space. The heterogeneity of the tropic-functional pattern of protozoan communities and its environmental drivers were studied in coastal waters of the Yellow Sea during a 1-year cycle. Samples were collected using the glass slide method at four stations within a water pollution gradient. A second-stage matrix-based analysis was used to summarize spatial variation in the annual pattern of the functional structure. A clustering analysis revealed significant variability in the trophic-functional pattern among the four stations during the 1-year cycle. The heterogeneity in the trophic-functional pattern of the communities was significantly related to changes in environmental variables, particularly ammonium-nitrogen and nitrates, alone or in combination with dissolved oxygen. These results suggest that the heterogeneity in annual patterns of protozoan trophic-functional structure may reflect water quality status in coastal ecosystems. Copyright © 2017. Published by Elsevier Ltd.

  2. Sustainable Land-Use Planning to Improve the Coastal Resilience of the Social-Ecological Landscape

    Directory of Open Access Journals (Sweden)

    Min Kim

    2017-06-01

    Full Text Available The dynamics of land-use transitions decrease the coastal resilience of the social-ecological landscape (SEL, particularly in light of the fact that it is necessary to analyze the causal relationship between the two systems because operations of the social system and the ecological system are correlated. The purpose of this study is to analyze the dynamics of the coastal SEL and create a sustainable land-use planning (SLUP strategy to enhance coastal resilience. The selected study site was Shindu-ri, South Korea, where land-use transitions are increasing and coastal resilience is therefore decreasing. Systems thinking was used to analyze the study, which was performed in four steps. First, the issues affecting the coastal area in Shindu-ri were defined as coastal landscape management, the agricultural structure, and the tourism industry structure. Second, the main variables for each issue were defined, and causal relationships between the main variables were created. Third, a holistic causal loop diagram was built based on both dynamic thinking and causal thinking. Fourth, five land-uses, including those of the coastal forest, the coastal grassland, the coastal dune, the agricultural area, and developed sites, were selected as leverage points for developing SLUP strategies to increase coastal resilience. The results show that “decrease in the size of the coastal forest”, “decrease in the size of the coastal dune”, and “increase in the size of the coastal grasslands” were considered parts of a land-use plan to enhance the resilience of the Shindu-ri SEL. This study developed integrated coastal land-use planning strategies that may provide effective solutions for complex and dynamic issues in the coastal SEL. Additionally, the results may be utilized as basic data to build and implement coastal land-use planning strategies.

  3. Community-Based Coastal Resource Management (CB-CRM: a Case Study f Mariveles, Bataan, Philippines

    Directory of Open Access Journals (Sweden)

    Andrew L.L Munchal

    2016-06-01

    Full Text Available This paper addressed the issue of sustainable coastal resource management through a successful Community-Based Coastal Resource Management (CB-CRM Program in the Municipality of Mariveles, province of Bataan in the Philippines. The paper investigated how governance and institutional and legislative framework, and the concept of sustainable development complemented  each  other  to  promote  good  local  eco-governance in  the management and protection of finite local marine resources. Specifically, it analyzed how the local fisherfolk community of Mariveles utilized efficiently their finite marine resources in the context of eco-governance. It also investigated how the cooperative efforts of various stakeholders: peoples’ organizations (POs,  local  government unit  (LGU,  and  a  non- government organization (NGO  in  Mariveles, Bataan  affected  their  coastal  resources against environmental degradation and exploitation. This paper would benefit POs, LGUs, and NGOs in their quest for sustainable management and conservation of their limited coastal resources. This paper yielded the following findings. First, POs and NGOs engage when NGOs can strengthen the POs’ capacity building through the transfer of skills and technology, when NGOs can enhance the POs’ indigenous knowledge, and when NGOs are more knowledgeable of formal venues of LGU participation. Second, LGUs, NGOs and POs engage when POs and NGOs can complement each other to strengthen their capacity building, and when NGOs can help implement environmental programs that are beneficial to the POs. Third, NGOs and POs engage when POs are threatened by elite power, and when NGOs want their environmental issues on LGU’s legislative agenda. Finally, NGOs and POs engage when they see possible LGU cooperation. Participant observation through focus group discussion (FGD and key informants’ interview of different stakeholders was a  primary  source  of

  4. Trickle-down boundary conditions in aeolian dune-field pattern formation

    Science.gov (United States)

    Ewing, R. C.; Kocurek, G.

    2015-12-01

    One the one hand, wind-blown dune-field patterns emerge within the overarching boundary conditions of climate, tectonics and eustasy implying the presence of these signals in the aeolian geomorphic and stratigraphic record. On the other hand, dune-field patterns are a poster-child of self-organization, in which autogenic processes give rise to patterned landscapes despite remarkable differences in the geologic setting (i.e., Earth, Mars and Titan). How important are climate, tectonics and eustasy in aeolian dune field pattern formation? Here we develop the hypothesis that, in terms of pattern development, dune fields evolve largely independent of the direct influence of 'system-scale' boundary conditions, such as climate, tectonics and eustasy. Rather, these boundary conditions set the stage for smaller-scale, faster-evolving 'event-scale' boundary conditions. This 'trickle-down' effect, in which system-scale boundary conditions indirectly influence the event scale boundary conditions provides the uniqueness and richness of dune-field patterned landscapes. The trickle-down effect means that the architecture of the stratigraphic record of dune-field pattern formation archives boundary conditions, which are spatially and temporally removed from the overarching geologic setting. In contrast, the presence of an aeolian stratigraphic record itself, reflects changes in system-scale boundary conditions that drive accumulation and preservation of aeolian strata.

  5. Eastern Africa Coastal Forest Programme

    OpenAIRE

    Younge, A.

    2002-01-01

    The eastern African coastal forest ecoregion is recognised as one of Africa’s centres of species endemism, and is distributed over six countries (Somalia, Kenya, Tanzania, Mozambique, Zimbabwe and Malawi). Most is found in Kenya, Tanzania and Mozambique, which form our focal region. The coastal forests are fragmented, small and surrounded by poor communities that have a high demand for land and forest resources. Although coastal forests have significant cultural and traditional...

  6. Water-use dynamics of a peat swamp forest and a dune forest in Maputaland, South Africa

    Directory of Open Access Journals (Sweden)

    A. D. Clulow

    2013-05-01

    Full Text Available Peat swamp forests are the second rarest forest type found in South Africa while dune forests have been under severe threat through mining and agriculture. Both forest types exist in the conservation area, and World Heritage site, known as the iSimangaliso Wetland Park on the East coast of South Africa. The area is prone to severe droughts (Taylor et al., 2006 and recent attempts to understand the local water balance revealed that there was insufficient information on the water use of the indigenous forests of the area. The peat swamp forest and dune forest sites studied in this research were located within close proximity to each other, yet, are characterised by different landscape positions in terms of water availability. The coastal dune forest soil profile was generally dry and sandy and the tree roots did not have access to the water table. In contrast the peat swamp forest is located in an interdunal wetland where the trees have permanent access to water. The climate at both sites is subtropical with a mean annual precipitation of 1200 mm yr−1. However, over 20 months of measurement, the first summer (October 2009 to March 2010 was drier (424 versus 735 mm than the second summer (October 2010 to March 2011 emphasising the variability of the rainfall in the area and providing a wide range of conditions measured. The sap flow of an evergreen, overstory Syzygium cordatum and a semi-deciduous, understory Shirakiopsis elliptica were measured in the peat swamp forest using the heat ratio method. The Syzygium cordatum water use was not highly seasonal and the daily maximum water use ranged from approximately 30 L d−1 in winter to 45 L d−1 in summer whereas the extit{Shirakiopsis elliptica} water use was more seasonal at 2 L d−1 in winter and 12 L d−1 in summer. The water use of the Syzygium cordatum was not influenced by seasonal rainfall variations and was actually higher in the drier summer (October 2009 to March 2010. Three trees of

  7. Geologic framework influences on the geomorphology of an anthropogenically modified barrier island: Assessment of dune/beach changes at Fire Island, New York

    Science.gov (United States)

    Lentz, E.E.; Hapke, C.J.

    2011-01-01

    Antecedent geology plays a crucial role in determining the inner-shelf, nearshore, and onshore geomorphology observed in coastal systems. However, the influence of the geologic framework on a system is difficult to extract when evaluating responses to changes due to storms and anthropogenic modifications, and few studies have quantified the potential for these influences in dune/beach environments. This study evaluates topographic change to the dune/beach system at Fire Island, New York over a ten year period (1998-2008) at two sites representing eastern and western reaches of the island where morphology has been shown to vary. The sites are situated along swaths of coast eroding differentially and where the inner shelf geologic framework differs substantially. Fewer large storms occurred in the first half of the study period, compared with the later part of the study period which includes several severe and prolonged extratropical storms. Additionally, a major beach replenishment project was conducted at one of the study sites. Topographic data from LiDAR and RTK GPS surveys are used to construct high-resolution 3D surfaces, which are used to determine volumetric change and to extract 2D alongshore features and profiles for analysis. The study sites help to further characterize morphologic differences between eastern and western reaches of the island. The western site displays higher sand volumes, lower dunes, and a lower gradient profile slope when compared with the eastern site. In addition to these fundamental morphologic differences, the two sites also differ significantly in their response to coastal storms and in the fact that their replenishment histories are different. The replenished areas show reduced vulnerability to storms through minimal volume loss and shoreline accretion that should be considered when evaluating the response of replenished areas to episodic events. We propose that site-specific differences evident throughout the study period can be

  8. THE INNOVATIVE POLICY OPTIONS FOR COASTAL FISHERIES ECONOMIC DEVELOPMENT: A CASE OF KWANDANG BAY COASTAL ECOSYSTEM

    Directory of Open Access Journals (Sweden)

    Noel Taylor Moore

    2017-07-01

    Full Text Available Socio-environmental problems, such as climate change, pollution and habitat destruction, present serious challenges for fisheries economic development. The integration of interventions or investments within a coastal marine ecosystem, a defined spatial area, is considered important in the economic development of local communities leading to the planned outcomes of livelihoods, food security and conservation The coastal marine ecosystem, is the provider of products and services to the local economy adjacent to the ecosystem where the benefit flows, within that area, are interconnected. The roles of science, technology and innovation (STI are an integral part of these multi-dimensional interventions. Hence the need for an integrated approach for these interventions by government and/or through donor funded projects to enhance economic development of coastal communities. The policy framework proposed is therefore an STI perspective of the links between these intervention and investment options, based on a ‘fisheries economic development Hub’ (Hub and discussed using the multi-level perspective (MLP. The policy innovation proposal suggests an implementation strategy of a pilot project and analyses the selection and implications of a potential Indonesian site for the application of the Hub. This paper aims to introduce the MLP into the framework of coastal community-based fisheries economic development.   Key words: policy innovation. coastal marine ecosystem, fisheries economic development Hub, value chains, multi-level perspective (MLP

  9. Singing Sand Dunes

    Indian Academy of Sciences (India)

    ble low-frequency (s. 75–105 Hz), that can some- times be heard up to 10 km away. Scientific in- vestigations suggest that the sustained low fre- quency sound of sand dunes that resembles a pure note from a musical instrument, is due to the synchronized motion of well-sorted dry sand grains when they spontaneously ...

  10. Composition and variation of sediment bacterial and nirS-harboring bacterial communities at representative sites of the Bohai Gulf coastal zone, China.

    Science.gov (United States)

    Guan, Xiangyu; Zhu, Lingling; Li, Youxun; Xie, Yuxuan; Zhao, Mingzhang; Luo, Ximing

    2014-04-01

    With rapid urbanization, anthropogenic activities are increasingly influencing the natural environment of the Bohai Bay. In this study, the composition and variation of bacterial and nirS-harboring bacterial communities in the coastal zone sediments of the Bohai Gulf were analyzed using PCR-based clone libraries. A total of 95 genera were detected in the bacterial communities, with Proteobacteria (72.1 %), Acidobacteria (10.5 %), Firmicutes (1.7 %), Bacteroidetes (1.4 %), Chloroflexi (0.7 %) and Planctomycetes (0.7 %) being the dominated phyla. The NirS sequences were divided into nine Clusters (A-I). Canonical correlation analysis showed that the bacterial or denitrifying communities were correlated with different environmental factors, such as total organic carbon, total nitrogen, ammonium, sulfate, etc. Furthermore, bacterial communities' composition and diversity are influenced by oil exploration, sewage discharge and other anthropogenic activities in the coastal area of the Bohai Sea. Thus, this study provided useful information on further research on regional or global environmental control and restore.

  11. Upstream sediment input effects on experimental dune trough scour in sediment mixtures

    NARCIS (Netherlands)

    Kleinhans, M.G.

    2005-01-01

    Understanding causes of dune irregularity, especially dune trough scour, is important for the modeling of vertical sorting of sediment mixtures in morphological models of rivers with sediment mixtures. Sediment in dunes is generally sorted in a fining-upward manner, which affects the sediment

  12. Large-eddy simulations of unidirectional water flow over dunes

    Science.gov (United States)

    Grigoriadis, D. G. E.; Balaras, E.; Dimas, A. A.

    2009-06-01

    The unidirectional, subcritical flow over fixed dunes is studied numerically using large-eddy simulation, while the immersed boundary method is implemented to incorporate the bed geometry. Results are presented for a typical dune shape and two Reynolds numbers, Re = 17,500 and Re = 93,500, on the basis of bulk velocity and water depth. The numerical predictions of velocity statistics at the low Reynolds number are in very good agreement with available experimental data. A primary recirculation region develops downstream of the dune crest at both Reynolds numbers, while a secondary region develops at the toe of the dune crest only for the low Reynolds number. Downstream of the reattachment point, on the dune stoss, the turbulence intensity in the developing boundary layer is weaker than in comparable equilibrium boundary layers. Coherent vortical structures are identified using the fluctuating pressure field and the second invariant of the velocity gradient tensor. Vorticity is primarily generated at the dune crest in the form of spanwise "roller" structures. Roller structures dominate the flow dynamics near the crest, and are responsible for perturbing the boundary layer downstream of the reattachment point, which leads to the formation of "horseshoe" structures. Horseshoe structures dominate the near-wall dynamics after the reattachment point, do not rise to the free surface, and are distorted by the shear layer of the next crest. The occasional interaction between roller and horseshoe structures generates tube-like "kolk" structures, which rise to the free surface and persist for a long time before attenuating.

  13. Quantifying spatial and temporal trends in beach-dune volumetric changes using spatial statistics

    Science.gov (United States)

    Eamer, Jordan B. R.; Walker, Ian J.

    2013-06-01

    Spatial statistics are generally underutilized in coastal geomorphology, despite offering great potential for identifying and quantifying spatial-temporal trends in landscape morphodynamics. In particular, local Moran's Ii provides a statistical framework for detecting clusters of significant change in an attribute (e.g., surface erosion or deposition) and quantifying how this changes over space and time. This study analyzes and interprets spatial-temporal patterns in sediment volume changes in a beach-foredune-transgressive dune complex following removal of invasive marram grass (Ammophila spp.). Results are derived by detecting significant changes in post-removal repeat DEMs derived from topographic surveys and airborne LiDAR. The study site was separated into discrete, linked geomorphic units (beach, foredune, transgressive dune complex) to facilitate sub-landscape scale analysis of volumetric change and sediment budget responses. Difference surfaces derived from a pixel-subtraction algorithm between interval DEMs and the LiDAR baseline DEM were filtered using the local Moran's Ii method and two different spatial weights (1.5 and 5 m) to detect statistically significant change. Moran's Ii results were compared with those derived from a more spatially uniform statistical method that uses a simpler student's t distribution threshold for change detection. Morphodynamic patterns and volumetric estimates were similar between the uniform geostatistical method and Moran's Ii at a spatial weight of 5 m while the smaller spatial weight (1.5 m) consistently indicated volumetric changes of less magnitude. The larger 5 m spatial weight was most representative of broader site morphodynamics and spatial patterns while the smaller spatial weight provided volumetric changes consistent with field observations. All methods showed foredune deflation immediately following removal with increased sediment volumes into the spring via deposition at the crest and on lobes in the lee

  14. A Sharp View on River Dune Transition to Upper Stage Plane Bed

    NARCIS (Netherlands)

    Naqshband, S.; Hoitink, A.J.F.; Mcelroy, B.; Hurther, D.; Hulscher, S.J.M.H.

    2017-01-01

    Sandy river beds are dominated by rhythmic features known as dunes. Experimental investigations of turbulent flow and sediment transport over dunes have predominantly focused on equilibrium flows that are rare in natural rivers. Using a novel acoustic instrument over migrating dunes in a laboratory

  15. A sharp view on river dune transition to upper stage plane bed

    NARCIS (Netherlands)

    Naqshband, S.; Hoitink, A.J.F.; Mcelroy, B.; Hurther, D.; Hulscher, S.J.M.H.

    2017-01-01

    Sandy river beds are dominated by rhythmic features known as dunes. Experimental investigations of turbulent flow and sediment transport over dunes have predominantly focused on equilibrium flows that are rare in natural rivers. Using a novel acoustic instrument over migrating dunes in a laboratory

  16. Dune and ripple migration along Curiosity's traverse in Gale Crater on Mars

    Science.gov (United States)

    Silvestro, S.; Vaz, D.; Ewing, R. C.; Fenton, L. K.; Michaels, T. I.; Ayoub, F.; Bridges, N. T.

    2013-12-01

    The NASA Mars Science Laboratory (MSL) rover, Curiosity, has safely landed near a 35-km-long dark dune field in Gale Crater on Mars. This dune field lies along Curiosity's traverse to Aeolis Mons (Mt. Sharp). Here we present new evidence of aeolian activity and further estimate wind directions within the dune field through analysis of ripple migration with the COSI-Corr technique, which provides precise measurements of ripple displacement at the sub-pixel scale.The area analyzed is located ~10 km southwest of rover Curiosity's current position and ~4 km SW of its selected path through Aeolis Mons (Mt. Sharp) (Fig. 1a). Here barchan dunes with elongated horns and seif dunes coexist with more typical barchan and dome dunes (Fig. 1a, b), with slopes sculpted by two intersecting ripple crestline orientations trending at 45° and 330°. The range of dune types and ripple orientations indicate the dune field morphology is influenced by at least two winds from the NW and the NE. The direction of migration is toward the SW, suggesting the most recent sand transporting winds were from the NE (Fig. 1c). These results match previous predictions and can be used to forecast the wind conditions close to the entry point to Mt. Sharp. Fig. 1: a-b) Study area c) Ripple migration direction computed using the COSI-Corr technique

  17. Genetic diversity and temporal variation of the marine Synechococcus community in the subtropical coastal waters of Hong Kong.

    Science.gov (United States)

    Jing, Hongmei; Zhang, Rui; Pointing, Stephen B; Liu, Hongbin; Qian, Peiyuan

    2009-03-01

    The phylogenetic diversity of the marine Synechococcus community in the subtropical coastal waters of Hong Kong, China, was examined through intergenic transcribed spacer clone libraries. All the sequences obtained fell within both marine cluster A (MC-A) and B (MC-B), with MC-A phylotypes dominating throughout the year. Distinct phylogenetic lineages specific to Hong Kong waters were detected from both MC-A and MC-B. The highest Synechococcus community diversity occurred in December, but the highest Synechococcus abundance occurred in August. On the other hand, both the abundance and diversity of Synechococcus showed a minimum in February. The remarkable seasonal variations of Synechococcus diversity observed were likely the result of the changes of hydrographic condition modulated by monsoons. Principal component analysis revealed that the in situ abiotic water characteristics, especially salinity and water turbidity, explained much of the variability of the marine Synechococcus population diversity in Hong Kong coastal waters. In addition, the temporal changes of Synechococcus abundance were largely driven by water temperature.

  18. Epiphytic invertebrate patterns in coastal lakes along a gradient of salinity and water exchange with the sea

    Science.gov (United States)

    Obolewski, Krystian; Bąkowska, Martyna

    2017-10-01

    The species composition and abundance of epiphytic fauna inhabiting common reed (Phragmites australis (Cav.) Trin. ex Steud.) was performed in five coastal lakes in Słowiński National Park (southern Baltic coast in northern Poland). The lakes represent a salinity gradient (from freshwater to β-oligohaline waters) and four types of coastal lakes: (1) lagoon, L (Lake Łebsko, seawater enters it permanently); (2) coastal lake with periodically brackish water, CLB (Lake Gardno); (3) freshwater costal lake, CLF (Lake Smołdzińskie); and (4) coastal dune lakes, CLD (Dołgie Wielkie and Dołgie Małe). Using statistical ordination techniques, we found that the structure of epiphytic fauna (microinvertebrates and macroinvertebrates) is determined primarily by hydrological connectivity (water exchange) with the sea. Canonical Correspondence Analysis, coupled with variance partitioning, showed that hydrological connectivity accounted for 24% of the variation in the invertebrate community, followed by physico-chemical (19%) and trophic (8%) factors. Our results indicate that the assemblages of Ciliata-libera and Cnidaria are characteristic for L (β-oligohaline), Rotifera, Suctoria, Chaetogaster sp., Gastropoda and Trichoptera are characteristic for CLB (limnetic/β-oligohaline), but no taxonomic groups are characteristic for CLF and CLD (both limnetic). The index of multivariate dispersion showed a decreasing trend with the increasing lake isolation from the open sea, except for CLD. However, in terms of the structure of epiphytic fauna, Multi-Response Permutation Procedures showed that CLD significantly differed only from CLB. Our results suggest that the identified characteristic taxonomic groups of plant-associated macroinvertebrates have a high potential to be used as bioindicators of salinity and water exchange with the sea, due to their sensitivity to environmental stress.

  19. Dune Mining and the Nhlabane Estuary, South Africa: the Effect of a Dredger Crossing on the Zoobenthic Community

    International Nuclear Information System (INIS)

    Vivier, L.; Cyrus, D.P.

    1999-01-01

    The Nhlabane Estuary, located on the north-east coast of South Africa, is situated in a titanium dune mining lease area. During 1993, a mining dredger and concentrator crossed the middle reaches of the estuary. For this purpose, two berm walls were constructed across the estuary. Two impacts stemmed from the crossing. A series of fine sediment intrusions into the estuary from the berm wall area occurred during late 1993 and early 1994 and caused a rapid decline in benthic densities and number of taxa. Recovery of the affected area was slow and characterized by initial proliferation of opportunistic colonizers. The berm walls, which divided the estuary in half, were kept in place for nearly three years and caused changes in water quality and the benthic community of the upper and lower halves of the estuary. Artificial breaching of the estuary in August 1995 and removal of the berm walls in May 1996 initiated recovery of the estuary. The success of a second dredger crossing, scheduled for January 1999, depends on addressing the mistakes made during the first crossing and on the speed with which the carefully planned crossing operation, berm wall removal and estuary rehabilitation proceed

  20. The effects of dune slopes and material heterogeneity on the thermal behavior of dune fields in Mars' Southern Hemisphere

    Science.gov (United States)

    O'Shea, P. M.; Putzig, N. E.; Van Kooten, S.; Fenton, L. K.

    2015-12-01

    We analyzed the effects of slopes on the thermal properties of three dune fields in Mars' southern hemisphere. Although slope has important thermal effects, it is not the main driver of observed apparent thermal inertia (ATI) for these dunes. Comparing the ATI seasonal behavior as derived from Thermal Emission Spectrometer (TES) data with that modeled for compositional heterogeneities, we found that TES results correlate best with models of duricrust overlying and/or horizontally mixing with fines. We measured slopes and aspects in digital terrain models created from High Resolution Imaging Science Experiment (HiRISE) images of dunes within Proctor, Kaiser, and Wirtz craters. Using the MARSTHERM web toolset, we incorporated the slopes and aspects together with TES albedo, TES thermal inertia, surface pressure, and TES dust opacity, into models of seasonal ATI. Models that incorporate sub-pixel slopes show seasonal day and night ATI values that differ from the TES results by 0-300 J m-2 K-1 s-½. In addition, the models' day-night differences are opposite in sign from those of the TES results, indicating that factors other than slope are involved. We therefore compared the TES data to model results for a broad range of horizontally mixed and two-layered surfaces to seek other possible controls on the observed data, finding that a surface layer of higher thermal inertia is a likely contributor. However, it is clear from this study that the overall composition and morphology of the dune fields are more complex than currently available models allow. Future work will combine slopes with other model parameters such as multi-layered surfaces and lateral changes in layer thickness. Coupling these improvements with broader seasonal coverage from the Thermal Emission Imaging System (THEMIS) at more thermally favorable times of day would allow more accurate characterization of dune thermal behavior.

  1. Numerical modelling of flow structures over idealized transverse aeolian dunes of varying geometry

    Science.gov (United States)

    Parsons, Daniel R.; Walker, Ian J.; Wiggs, Giles F. S.

    2004-04-01

    A Computational Fluid Dynamics (CFD) model (PHOENICS™ 3.5) previously validated for wind tunnel measurements is used to simulate the streamwise and vertical velocity flow fields over idealized transverse dunes of varying height ( h) and stoss slope basal length ( L). The model accurately reproduced patterns of: flow deceleration at the dune toe; stoss flow acceleration; vertical lift in the crest region; lee-side flow separation, re-attachment and reversal; and flow recovery distance. Results indicate that the flow field over transverse dunes is particularly sensitive to changes in dune height, with an increase in height resulting in flow deceleration at the toe, streamwise acceleration and vertical lift at the crest, and an increase in the extent of, and strength of reversed flows within, the lee-side separation cell. In general, the length of the separation zone varied from 3 to 15 h from the crest and increased over taller, steeper dunes. Similarly, the flow recovery distance ranged from 45 to >75 h and was more sensitive to changes in dune height. For the range of dune shapes investigated in this study, the differing effects of height and stoss slope length raise questions regarding the applicability of dune aspect ratio as a parameter for explaining airflow over transverse dunes. Evidence is also provided to support existing research on: streamline curvature and the maintenance of sand transport in the toe region; vertical lift in the crest region and its effect on grainfall delivery; relations between the turbulent shear layer and downward forcing of flow re-attachment; and extended flow recovery distances beyond the separation cell. Field validation is required to test these findings in natural settings. Future applications of the model will characterize turbulence and shear stress fields, examine the effects of more complex isolated dune forms and investigate flow over multiple dunes.

  2. Questioning the environmental stress hypothesis for gall diversity of restinga vegetation on dunes

    OpenAIRE

    Arriola, Ígor A.; F. MeloJr., JoãoCarlos; S. Isaias, RosyMary

    2015-01-01

    AbstractThe Atlantic Coast Restinga is a mosaic of plant communities with a distinct floristic and phytophysiognomy, exposed to luminous, thermal, and saline stresses. Plants of the restinga must have special features commonly associated to xeric environments, and are expected to host a high diversity of galling herbivores. We studied gall morphotypes, and recorded the diversity of galls on plants growing in sand dunes in a remnant area of restinga (Acaraí State Park) in São Francisco do Sul,...

  3. Disentangling the influences of habitat structure and limnological predictors on stream fish communities of a coastal basin, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Fabio Cop Ferreira

    Full Text Available In stream environments habitat structure and limnological factors interact regulating patterns of energy and material transfer and affecting fish communities. In the coastal basins of Southeastern Brazil, limnological and structural characteristics differ between clear and blackwaters streams. The former have a diversity of substrate types, higher water velocities, and lower water conductivity, while the latter have sandy substrate, tea-colored and acidic waters, and low water velocities. In this study, we verified the relative importance of habitat structure and limnological variables in predicting patterns of variation in stream fish communities. Eight first to third order streams were sampled in the coastal plain of Itanhaém River basin. We captured 34 fish species and verified that community structure was influenced by physical habitat and limnology, being the former more important. A fraction of the variation could not be totally decomposed, and it was assigned to the joint influence of limnology and habitat structure. Some species that were restricted to blackwater streams, may have physiological and behavioral adaptations to deal with the lower pH levels. When we examined only the clearwater streams, all the explained variation in fish community composition was assigned to structural factors, which express specific preferences for different types of habitats.

  4. Effects of High Hydrostatic Pressure on Coastal Bacterial Community Abundance and Diversity

    Science.gov (United States)

    Marietou, Angeliki

    2014-01-01

    Hydrostatic pressure is an important parameter influencing the distribution of microbial life in the ocean. In this study, the response of marine bacterial populations from surface waters to pressures representative of those under deep-sea conditions was examined. Southern California coastal seawater collected 5 m below the sea surface was incubated in microcosms, using a range of temperatures (16 to 3°C) and hydrostatic pressure conditions (0.1 to 80 MPa). Cell abundance decreased in response to pressure, while diversity increased. The morphology of the community also changed with pressurization to a predominant morphotype of small cocci. The pressure-induced community changes included an increase in the relative abundance of Alphaproteobacteria, Gammaproteobacteria, Actinobacteria, and Flavobacteria largely at the expense of Epsilonproteobacteria. Culturable high-pressure-surviving bacteria were obtained and found to be phylogenetically similar to isolates from cold and/or deep-sea environments. These results provide novel insights into the response of surface water bacteria to changes in hydrostatic pressure. PMID:25063663

  5. Dune Ecosystem Management of the Razim-Sinoie Littoral Bar (Romania

    Directory of Open Access Journals (Sweden)

    Gheorghe ROMANESCU

    2010-12-01

    case, the old secondary arms and canals: Buhaz-Zaton, Crasnicol and Dranov can be oversized. The shelter dams next to Gura Portita (in the centre caused important amounts of sediments to be held back, but at the same time a sediment shortage was felt to the south of these dams. In order to stop the littoral erosion and stabilize the dune system, underbrush can be planted, as an indigenous element which develops vigorously in the coastal dune environment.

  6. Enhancing resilience to coastal flooding from severe storms in the USA: international lessons

    Science.gov (United States)

    Lumbroso, Darren M.; Suckall, Natalie R.; Nicholls, Robert J.; White, Kathleen D.

    2017-08-01

    Recent events in the USA have highlighted a lack of resilience in the coastal population to coastal flooding, especially amongst disadvantaged and isolated communities. Some low-income countries, such as Cuba and Bangladesh, have made significant progress towards transformed societies that are more resilient to the impacts of cyclones and coastal flooding. To understand how this has come about, a systematic review of the peer-reviewed and grey literature related to resilience of communities to coastal flooding was undertaken in both countries. In both Cuba and Bangladesh the trust between national and local authorities, community leaders and civil society is high. As a consequence evacuation warnings are generally followed and communities are well prepared. As a result over the past 25 years in Bangladesh the number of deaths directly related to cyclones and coastal flooding has decreased, despite an increase of almost 50 % in the number of people exposed to these hazards. In Cuba, over the course of eight hurricanes between 2003 and 2011, the normalized number of deaths related to cyclones and coastal floods was an order of magnitude less than in the USA. In low-income countries, warning systems and effective shelter/evacuation systems, combined with high levels of disaster risk-reduction education and social cohesion, coupled with trust between government authorities and vulnerable communities can help to increase resilience to coastal hazards and tropical cyclones. In the USA, transferable lessons include improving communication and the awareness of the risk posed by coastal surges, mainstreaming disaster risk reduction into the education system and building trusted community networks to help isolated and disadvantaged communities, and improve community resilience.

  7. Enhancing resilience to coastal flooding from severe storms in the USA: international lessons

    Directory of Open Access Journals (Sweden)

    D. M. Lumbroso

    2017-08-01

    Full Text Available Recent events in the USA have highlighted a lack of resilience in the coastal population to coastal flooding, especially amongst disadvantaged and isolated communities. Some low-income countries, such as Cuba and Bangladesh, have made significant progress towards transformed societies that are more resilient to the impacts of cyclones and coastal flooding. To understand how this has come about, a systematic review of the peer-reviewed and grey literature related to resilience of communities to coastal flooding was undertaken in both countries. In both Cuba and Bangladesh the trust between national and local authorities, community leaders and civil society is high. As a consequence evacuation warnings are generally followed and communities are well prepared. As a result over the past 25 years in Bangladesh the number of deaths directly related to cyclones and coastal flooding has decreased, despite an increase of almost 50 % in the number of people exposed to these hazards. In Cuba, over the course of eight hurricanes between 2003 and 2011, the normalized number of deaths related to cyclones and coastal floods was an order of magnitude less than in the USA. In low-income countries, warning systems and effective shelter/evacuation systems, combined with high levels of disaster risk-reduction education and social cohesion, coupled with trust between government authorities and vulnerable communities can help to increase resilience to coastal hazards and tropical cyclones. In the USA, transferable lessons include improving communication and the awareness of the risk posed by coastal surges, mainstreaming disaster risk reduction into the education system and building trusted community networks to help isolated and disadvantaged communities, and improve community resilience.

  8. 36 CFR 7.80 - Sleeping Bear Dunes National Lakeshore.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Sleeping Bear Dunes National Lakeshore. 7.80 Section 7.80 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.80 Sleeping Bear Dunes National...

  9. Rainwater Harvesting-based Safe Water Access in Diarrhea-endemic Coastal Communities of Bangladesh under Threats of Climate Change

    Science.gov (United States)

    Akanda, A. S.; Redwan, A. M.; Ali, M. A.; Alam, M.; Jutla, A.; Colwell, R. R.

    2014-12-01

    The highly populated coastal floodplains of the Bengal Delta have a long history of water-related natural calamities such as droughts, floods, and cyclones. Population centers along the floodplain corridors of the GBM (Ganges-Brahmaputra-Meghna) river system remain vulnerable to such natural hazards and waterborne epidemic outbreaks due to increasing intensity and changing frequency of extreme events over many areas in the delta region. Such changes in hydrologic extremes and resulting environmental conditions would likely lengthen the transmission seasons of prevalent waterborne diseases and alter their geographic range as well as seasonality. In addition, the combination of changing upstream precipitation and temperature, and coastal sea-level rise are exposing a vast area in Southwestern Bangladesh to increased diarrheal disease outbreaks due to higher salinity and water scarcity in the dry season as well as coastal flooding and water resources contamination in the wet season. It is thus essential to establish sustainable safe water access practices in these regions for the rural communities of low-income people. The impact of climate change in the recent past on the people of coastal rural areas of Bangladesh has been severe, and the water sector is one of its biggest victims. Previously, pond and groundwater sources were considered dependable, but salinity intrusion in both water resources have left the vulnerable people with only a few scarce ponds and forced them to depend more on rainwater than before. The poorest group is suffering the most for this crisis even though paying more of the percentage of their income especially in the dry season (December-March). As rainwater is their most preferred and dependable option during this part of the year, outbreaks of waterborne diseases can be minimized by installing rainwater harvesting systems with effective disinfection system at both household and community levels. In this study, we explore the technical

  10. Martian Dune Ripples as Indicators of Recent Surface Wind Patterns

    Science.gov (United States)

    Johnson, M.; Zimbelman, J. R.

    2015-12-01

    Sand dunes have been shown to preserve the most recent wind patterns in their ripple formations. This investigation continues the manual documentation of ripples on Martian dunes in order to assess surface wind flow. Study sites investigated must have clear HiRISE frames and be able to represent diverse locations across the surface, decided primarily by their spread of latitude and longitude values. Additionally, frames with stereo pairs are preferred because of their ability to create digital terrain models. This will assist in efforts to relate dune slopes and obstacles to ripple patterns. The search and analysis period resulted in 40 study sites with mapped ripples. Lines were drawn perpendicular to ripple crests across three adjacent ripples in order to document both ripple wavelength from line length and inferred wind direction from azimuth. It is not possible to infer a unique wind direction from ripple orientation alone and therefore these inferred directions have a 180 degree ambiguity. Initial results from all study sites support previous observations that the Martian surface has many dune types in areas with adequate sand supply. The complexity of ripple patterns varies greatly across sites as well as within individual sites. Some areas of uniform directionality for hundreds of kilometers suggest a unimodal wind regime while overlapping patterns suggest multiple dominant winds or seasonally varying winds. In most areas, form flow related to dune shape seems to have a large effect on orientation and must be considered along with the dune type. As long as the few steep slip faces on these small dunes are avoided, form flow can be considered the dominant cause of deviation from the regional wind direction. Regional results, wind roses, and comparisons to previous work will be presented for individual sites.

  11. Analysis of beach morphodynamics on the Bragantinian mangrove peninsula (Pará, North Brazil) as prerequisite for coastal zone management recommendations

    Science.gov (United States)

    Krause, Gesche; Soares, Cidiane

    2004-05-01

    A beach profile monitoring programme was initiated in 1997 as a contribution to the development of recommendations for an integrated coastal zone management scheme of the mangrove peninsula of Bragança, State of Pará (North Brazil). It was the first scientific investigation on the coastal morphodynamics in a mangrove environment, which was opened for human use only since the mid-1970s. The observations were carried out on five sections for 4 years, on a fortnightly basis whenever possible. Temporal evolution of the beach morphology was assessed using time series of beach height, changes in profile shape, sediment transport calculations, and photographs. This unique data set for new settlement areas in this mangrove-dominated coastal zone illuminates the role of the interaction between human activities and natural coastal dynamics. Four coastal cells were identified as coastal management units, each with specific dynamic behaviour and utilisation by humans. The cells are rather small with dimensions in the order of 1-3 km. Only one of the units (cell 1) had a stable coastline during the 4 years of observation, while all others are eroding. Clearing of vegetation is the principal reason for the enhancement of the natural chronic erosion at these sites. In the wake of increasing tourism, housing was erected on the first dune ridge (cell 2) with much damage to the natural vegetation. In this unit, erosion is predominantly targeted on the dunes. In cell 3, the most important reason for the increased erosion is clearing of the adjacent fringing mangroves. This is also true for cell 4, but additionally the construction of large fishing traps, which artificially entrap sand and create sandbanks and thereby increase velocities in the tidal channel tend to enhance erosion at the shoreline. Only for cell 1 can protection measures for the still available vegetation be recommended while a planned retreat of many tourism facilities and fishermen's housings should be included

  12. Sediment flux and airflow on the stoss slope of a barchan dune

    Science.gov (United States)

    Lancaster, N.; Nickling, W. G.; Neuman, C. K. McKenna; Wyatt, V. E.

    1996-09-01

    Measurements of sediment flux on the windward slope of an isolated barchan using an array of 30 sand traps provide new data that can constrain models of dune dynamics. The data show that at low wind incident speeds, flux increases up the dune exponentially, whereas at higher wind speeds the increase with distance approaches linearity. Wind profile measurements, conducted at the same time as the flux measurements, indicate that, although wind speed at a given height increases by 1.2 times from dune toe to brinkline, wind shear velocity derived from the profile data decreases up the dune and is in many cases below transport threshold values. This demonstrates that conventional wind profiles, derived from anemometry on dunes, do not measure the part of the boundary layer that is significant for sediment transport.

  13. The role of benthic macrophytes and their associated macroinvertebrate community in coastal lagoon resistance to eutrophication.

    Science.gov (United States)

    Lloret, Javier; Marín, Arnaldo

    2009-12-01

    Eutrophication is widely recognised as one of the major menaces to coastal environments, particularly enclosed bays and lagoons. Although there is a general understanding of the consequences of eutrophication in these systems, there is a lack of sufficient knowledge concerning biotic feedbacks that influence eutrophication patterns and the resistance capacity of coastal environments. In this paper, the isotope ratios of main producers and consumers of a Mediterranean lagoon were examined in order to elucidate the fate of anthropogenic inputs from the main watercourse flowing into the lagoon. The results of the study of stable isotope data in the Mar Menor lagoon reflected that the whole benthic community plays an important role as a natural 'filter' that removes excess nutrients from the water column and stores them in the sediments, thereby enhancing lagoon resistance to eutrophication.

  14. The role of benthic macrophytes and their associated macroinvertebrate community in coastal lagoon resistance to eutrophication

    International Nuclear Information System (INIS)

    Lloret, Javier; Marin, Arnaldo

    2009-01-01

    Eutrophication is widely recognised as one of the major menaces to coastal environments, particularly enclosed bays and lagoons. Although there is a general understanding of the consequences of eutrophication in these systems, there is a lack of sufficient knowledge concerning biotic feedbacks that influence eutrophication patterns and the resistance capacity of coastal environments. In this paper, the isotope ratios of main producers and consumers of a Mediterranean lagoon were examined in order to elucidate the fate of anthropogenic inputs from the main watercourse flowing into the lagoon. The results of the study of stable isotope data in the Mar Menor lagoon reflected that the whole benthic community plays an important role as a natural 'filter' that removes excess nutrients from the water column and stores them in the sediments, thereby enhancing lagoon resistance to eutrophication.

  15. Monitoring of desert dune topography by multi angle sensors

    Science.gov (United States)

    Yun, J.; Kim, J.; Choi, Y.; Yun, H.

    2011-12-01

    Nowadays, the sandy desert is rapidly expanding world widely and results in a lot of risks in the socio-econimical aspects as well as the anthropogenic activities. For example, the increasing occurrences of mineral dust storm which presumably originated from the sandy deserts in northwest China become a serious threat in human activities as well as public health over Far East Asian area as the interpretation by the MODIS analysis (Zhang et al., 2007) and the particle trajectory simulation with HYSPLYT (HYbrid Single-Particle Lagrangian Integrated Trajectory) (Kim et al., 2011) identified. Since the sand dune activity has been recognized as an essential indicator of the progressive desertification, it is important to establish the monitoring method for the variations of topographic properties by the dune activities such as local roughness. Thus it will provide the crucial data about the extent and the transition of sandy desert. For example, it is well known the aerodynamic roughness lengths Zo which can be driven from the specialized sensor such as POLDER (POLarization and Directionality of the Earth's Reflectances) is essential to understand desert dune characteristics. However, for the multi temporal observation of dune fields, the availability of data set to extract Zo is limited. Therefore, we employed MISR (Multi angle imaging Spectro Radiometer) image sequence to extract multi angle topographic parameters such as NDAI (Normalized Difference Angular Index) or the variation of radiance with the viewing geometry which are representing the characteristics of target desert topography instead of Zo. In our approach, NDAI were expanded to the all viewing angles and then compared over the target sandy desert and the surrounding land covers. It showed very strong consistencies according to the land cover type and especially over the dynamic dune fields. On the other hands, the variation of NDAIs of sandy desert combining with the metrological observations were

  16. Linking Activity and Function to Ecosystem Dynamics in a Coastal Bacterioplankton Community

    Directory of Open Access Journals (Sweden)

    Scott Michael Gifford

    2014-04-01

    Full Text Available For bacterial communities containing hundreds to thousands of distinct populations, connecting functional processes and environmental dynamics at high taxonomic resolution has remained challenging. Here we use the expression of ribosomal proteins (%RP as a proxy for in situ activity of 200 taxa within 20 metatranscriptomic samples in a coastal ocean time series encompassing both seasonal variability and diel dynamics. %RP patterns grouped the taxa into seven activity clusters with distinct profiles in functional gene expression and correlations with environmental gradients. Clusters 1-3 had their highest potential activity in the winter and fall, and included some of the most active taxa, while Clusters 4-7 had their highest potential activity in the spring and summer. Cluster 1 taxa were characterized by gene expression for motility and complex carbohydrate degradation (dominated by Gammaproteobacteria and Bacteroidetes, and Cluster 2 taxa by transcription of genes for amino acid and aromatic compound metabolism and aerobic anoxygenic phototrophy (Roseobacter. Other activity clusters were enriched in transcripts for proteorhodopsin and methylotrophy (Cluster 4; SAR11 and methylotrophs, photosynthesis and attachment (Clusters 5 and 7; Synechococcus, picoeukaryotes, Verucomicrobia, and Planctomycetes, and sulfur oxidation (Cluster 7; Gammaproteobacteria. The seasonal patterns in activity were overlain, and sometimes obscured, by large differences in %RP over shorter day-night timescales. Seventy-eight taxa, many of them heterotrophs, had a higher %RP activity index during the day than night, indicating strong diel activity at this coastal site. Emerging from these taxonomically- and time-resolved estimates of in situ microbial activity are predictions of specific ecological groupings of microbial taxa in a dynamic coastal environment.

  17. Exploring the Impacts of Anthropogenic Disturbance on Seawater and Sediment Microbial Communities in Korean Coastal Waters Using Metagenomics Analysis

    Directory of Open Access Journals (Sweden)

    Nam-Il Won

    2017-01-01

    Full Text Available The coastal ecosystems are considered as one of the most dynamic and vulnerable environments under various anthropogenic developments and the effects of climate change. Variations in the composition and diversity of microbial communities may be a good indicator for determining whether the marine ecosystems are affected by complex forcing stressors. DNA sequence-based metagenomics has recently emerged as a promising tool for analyzing the structure and diversity of microbial communities based on environmental DNA (eDNA. However, few studies have so far been performed using this approach to assess the impacts of human activities on the microbial communities in marine systems. In this study, using metagenomic DNA sequencing (16S ribosomal RNA gene, we analyzed and compared seawater and sediment communities between sand mining and control (natural sites in southern coastal waters of Korea to assess whether anthropogenic activities have significantly affected the microbial communities. The sand mining sites harbored considerably lower levels of microbial diversities in the surface seawater community during spring compared with control sites. Moreover, the sand mining areas had distinct microbial taxonomic group compositions, particularly during spring season. The microbial groups detected solely in the sediment load/dredging areas (e.g., Marinobacter, Alcanivorax, Novosphingobium are known to be involved in degradation of toxic chemicals such as hydrocarbon, oil, and aromatic compounds, and they also contain potential pathogens. This study highlights the versatility of metagenomics in monitoring and diagnosing the impacts of human disturbance on the environmental health of marine ecosystems from eDNA.

  18. Comparisons of Unconsolidated Sediments Analyzed by APXS (MSL-Curiosity) within Gale Crater, Mars: Soils, Sands of the Barchan and Linear Dunes of the Active Bagnold Dune Field, and Ripple-field Sands.

    Science.gov (United States)

    Thompson, L. M.; O'Connell-Cooper, C.; Spray, J. G.; Gellert, R.; Boyd, N. I.; Desouza, E.

    2017-12-01

    The MSL-APXS has analyzed a variety of unconsolidated sediments within the Gale impact crater, including soils, sands from barchan [High, Namib dunes], and linear dunes [Nathan Bridges, Mount Desert dunes], within the active Bagnold dune field, and sands from two smaller ripple fields ("mega-ripples"). The Gale "soils" (unsorted, unconsolidated sediments, ranging from fine-grained particles (including dust) to coarser "pebbly" material [>2 mm]), are, to a large degree, similar to Martian basaltic soils quantified by APXS, at Gusev crater (MER-A_Spirit) and Meridiani Planum (MER-B_Opportunity). Some local contributions are indicated by, for example, the enriched K levels (relative to a martian average basaltic soil [ABS]) within coarser Gale soil samples, and a Cr, Mn, Fe enrichment within finer-grained samples. Sands (grain size 62 µm to 2 mm) of the Bagnold dunes, generally, exhibit elevated Mg and Ni, indicating enrichment from olivine and pyroxene, but depleted S, Cl and Zn, indicating high activity levels and low dust. Compositional differences, related both to position within a dune (i.e., crest versus off-crest sand), and type of dune (linear versus barchan), are identified. Off-crest sands have Na, Al, Si, K, P contents similar to (or slightly depleted, relative to) the ABS, enrichment in Mg, and low dust content, whilst crest sands contain very high Mg and Ni (relative to the ABS), low felsic elemental concentrations and very low dust content. Cr is significantly enriched (and, to a lesser degree, Mn, Fe, Ti) in the off-crest sands of the linear dunes. In contrast, barchan dunes off-crest sands have Cr, Mn, Fe, and Ti abundances similar to those in the Gale soils. Additionally, Ni concentrations in barchan dunes off-crest sands are enriched relative to the linear dunes. Analyses from a small, isolated "mega-ripple" reveal a composition similar to that of the Gale soils, including a high dust content. The second mega-ripple, within a larger ripple field, is

  19. Four Simple Questions: Evaluating the Effectiveness of Half-Day Community Workshops Designed to Increase Awareness of Coastal Cetacean Conservation Issues in Sarawak, Malaysia

    Science.gov (United States)

    Minton, Gianna; Poh, Anna Norliza Zulkifli; Ngeian, Jenny; Peter, Cindy; Tuen, Andrew Alek

    2012-01-01

    Community workshops were held in coastal locations in Sarawak to raise awareness of cetacean conservation. Interviews were conducted up to 2 years later in four "workshop communities" as well as four villages where workshops were not conducted. Comparison of responses between respondents who had attended workshops (n = 127) versus those…

  20. Relating sedimentary processes in the Bagnold Dunes to the development of crater basin aeolian stratification

    Science.gov (United States)

    Ewing, R. C.; Lapotre, M. G. A.; Lewis, K. W.; Day, M. D.; Stein, N.; Rubin, D. M.; Sullivan, R. J., Jr.; Banham, S.; Thomas, N. M.; Lamb, M. P.; Gupta, S.; Fischer, W. W.

    2017-12-01

    Wind-blown sand dunes are ubiquitous on the surface of Mars and are a recognized component of the martian stratigraphic record. Our current knowledge of the aeolian sedimentary processes that determine dune morphology, drive dune dynamics, and create aeolian cross-stratification are based upon orbital studies of ripple and dune morphodynamics, rover observations of stratification on Mars, Earth analogs, and experimental and theoretical studies of sand movement under martian conditions. Exploration of the Bagnold Dunes by the Curiosity Rover in Gale Crater, Mars provided the first opportunity to make in situ observations of martian dunes from the grain-to-dune scale. We used the suite of cameras on Curiosity, including Navigation Camera, Mast Camera, and Mars Hand Lens Imager. We measured grainsize and identified sedimentary processes similar to processes on terrestrial dunes, such as grainfall, grainflow, and impact ripples. Impact ripple grainsize had a median of 0.103 mm. Measurements of grainflow slopes indicate a relaxation angle of 29° and grainfall slopes indicate critical angles of at least 32°. Dissimilar to terrestrial dunes, large, meter-scale ripples form on all slopes of the dunes. The ripples form both sinuous and linear crestlines, have symmetric and asymmetric profiles, range in height between 12cm and 28cm, and host grainfall, grainflow, and impact ripples. The largest ripples are interpreted to integrate the annual wind cycle within the crater, whereas smaller large ripples and impact ripples form or reorient to shorter term wind cycling. Assessment of sedimentary processes in combination with dune type across the Bagnold Dunes shows that dune-field pattern development in response to a complex crater-basin wind regime dictates the distribution of geomorphic processes. From a stratigraphic perspective, zones of highest potential accumulation correlate with zones of wind convergence, which produce complex winds and dune field patterns thereby

  1. Sedimentary processes of the Bagnold Dunes: Implications for the eolian rock record of Mars

    Science.gov (United States)

    Ewing, R. C.; Lapotre, M. G. A.; Lewis, K. W.; Day, M.; Stein, N.; Rubin, D. M.; Sullivan, R.; Banham, S.; Lamb, M. P.; Bridges, N. T.; Gupta, S.; Fischer, W. W.

    2017-12-01

    The Mars Science Laboratory rover Curiosity visited two active wind-blown sand dunes within Gale crater, Mars, which provided the first ground-based opportunity to compare Martian and terrestrial eolian dune sedimentary processes and study a modern analog for the Martian eolian rock record. Orbital and rover images of these dunes reveal terrestrial-like and uniquely Martian processes. The presence of grainfall, grainflow, and impact ripples resembled terrestrial dunes. Impact ripples were present on all dune slopes and had a size and shape similar to their terrestrial counterpart. Grainfall and grainflow occurred on dune and large-ripple lee slopes. Lee slopes were 29° where grainflows were present and 33° where grainfall was present. These slopes are interpreted as the dynamic and static angles of repose, respectively. Grain size measured on an undisturbed impact ripple ranges between 50 μm and 350 μm with an intermediate axis mean size of 113 μm (median: 103 μm). Dissimilar to dune eolian processes on Earth, large, meter-scale ripples were present on all dune slopes. Large ripples had nearly symmetric to strongly asymmetric topographic profiles and heights ranging between 12 cm and 28 cm. The composite observations of the modern sedimentary processes highlight that the Martian eolian rock record is likely different from its terrestrial counterpart because of the large ripples, which are expected to engender a unique scale of cross stratification. More broadly, however, in the Bagnold Dune Field as on Earth, dune-field pattern dynamics and basin-scale boundary conditions will dictate the style and distribution of sedimentary processes.

  2. Dune recovery after storm erosion on a high-energy beach: Vougot Beach, Brittany (France)

    Science.gov (United States)

    Suanez, Serge; Cariolet, Jean-Marie; Cancouët, Romain; Ardhuin, Fabrice; Delacourt, Christophe

    2012-02-01

    On 10th March 2008, the high energy storm Johanna hit the French Atlantic coast, generating severe dune erosion on Vougot Beach (Brittany, France). In this paper, the recovery of the dune of Vougot Beach is analysed through a survey of morphological changes and hydrodynamic conditions. Data collection focused on the period immediately following storm Johanna until July 2010, i.e. over two and a half years. Results showed that the dune retreated by a maximum of almost 6 m where storm surge and wave attack were the most energetic. Dune retreat led to the creation of accommodation space for the storage of sediment by widening and elevating space between the pre- and post-storm dune toe, and reducing impacts of the storm surge. Dune recovery started in the month following the storm event and is still ongoing. It is characterised by the construction of "secondary" embryo dunes, which recovered at an average rate of 4-4.5 cm per month, although average monthly volume changes varied from - 1 to 2 m 3.m - 1 . These embryo dunes accreted due to a large aeolian sand supply from the upper tidal beach to the existing foredune. These dune-construction processes were facilitated by growth of vegetation on low-profile embryo dunes promoting backshore accretion. After more than two years of survey, the sediment budget of the beach/dune system showed that more than 10,000 m 3 has been lost by the upper tidal beach. We suggest that seaward return currents generated during the storm of 10th March 2008 are responsible for offshore sediment transport. Reconstitution of the equilibrium beach profile following the storm event may therefore have generated cross-shore sediment redistribution inducing net erosion in the tidal zone.

  3. Proceedings of the 79th Meeting of the Coastal Engineering Research Board, 6-10 June 2005 (Anchorage, AK)

    Science.gov (United States)

    2006-09-29

    integrated Coastal Community Vulnerability and Adaptation Program focused on improving the resilience of coastal communities to natural hazards and...in sharp contrast to the situation of a coastal community facing a serious erosion threat. The nature of the problem may be pretty clear, but the...products to improve the preparedness of communities, businesses, and government entities. As described in Section 8 of S.50, this Coastal

  4. Control parameters of the martian dune field positions at planetary scale: tests by the MCD

    Science.gov (United States)

    allemand, pascal

    2016-04-01

    The surface of Mars is occupied by more than 500 dunes fields mainly located inside impact craters of the south hemisphere and near the north polar cap. The questions of the activity of martian dunes and of the localization of the martian dune fields are not completely solved. It has been demonstrated recently by image observation and image correlation that some of these dune fields are clearly active. The sand flux of one of them has been even estimated. But there is no global view of the degree of activity of each the dune fields. (2)The topography of impact craters in which dune fields are localized is an important factor of their position. But there is no consensus of the effect of global atmospheric circulation on dune field localization. These two questions are addressed using the results of Mars Climate Database 5.2 (MCD) (Millour, 2015; Forget et al., 1999). The wind fields of the MCD have been first validated against the observations made on active dune fields. Using a classical transport law, the Drift Potential (DP) and the Relative Drift Potential (RDP) have been computed for each dune fields. A good correlation exists between the position of dune fields and specific values of these two parameters. The activity of each dune field is estimated from these parameters and tested on some examples by image observations. Finally a map of sand flow has been computed at the scale of the planet. This map shows that sand and dust is trapped in specific regions. These regions correspond to the area of dune field concentration.

  5. Comparison of primary production and pelagic community respiration rates in the coastal zone of the Gulf of Gdansk

    Directory of Open Access Journals (Sweden)

    Joanna K. York

    2001-09-01

    Full Text Available The organic matter production/respiration balance in the coastal water column was examined, both the primary production and community respiration being measured with the oxygen light-and-dark bottle method. Community respiration (CR was always lower than the gross primary production (GPP measured at a standard light intensity of 390 µE m-2 s-1, which amounted, on average, to 30% of GPP. During most of the in situ sampling period, the coastal system (6-7 m depth was found to be autotrophic, with depth-integrated GPP ranging from 6.7 mmoles O2 m-2 d-1 in December to 214.2 mmoles O2 m-2 d-1 in August, and CR ranging correspondingly from 6.0 to 177.7 mmoles O2 m-2 d-1. However, on some occasions heterotrophic conditions were recorded: depth-integrated GPP

  6. Biological soil crust as a bio-mediator alters hydrological processes in stabilized dune system of the Tengger Desert, China

    Science.gov (United States)

    Li, Xinrong

    2016-04-01

    Biological soil crust (BSC) is a vital component in the stabilized sand dunes with a living cover up to more than 70% of the total, which has been considered as a bio-mediator that directly influences and regulates the sand dune ecosystem processes. However, its influences on soil hydrological processes have been long neglected in Chinese deserts. In this study, BSCs of different successional stages were chose to test their influence on the hydrological processes of stabilized dune, where the groundwater deep exceeds 30m, further to explore why occur the sand-binding vegetation replacement between shrubs and herbs. Our long-term observation (60 years) shows that cyanobacteria crust has been colonized and developed after 3 years since the sand-binding vegetation has been established and dune fixation using planted xerophytic shrubs and made sand barrier (straw-checkerboard) on shifting dune surface, lichen and moss crust occurred after 20 years, and the cover of moss dominated crust could reach 70 % after 50 years. The colonization and development of BSC altered the initial soil water balance of revegetated areas by influencing rainfall infiltration, soil evaporation and dew water entrapment. The results show that BSC obviously reduced the infiltration that occurred during most rainfall events (80%), when rainfall was greater than 5 mm or less than 20 mm. The presence of BSC reduced evaporation of topsoil after small rainfall (<5 mm) because its high proportion of finer particles slowed the evaporation rate, thus keeping the water in the soil surface longer, and crust facilitated topsoil evaporation when rainfall reached 10 mm. The amount of dew entrapment increases with the succession of BSC. Moreover, the effect of the later successional BSC to dew entrapment, rainfall infiltration and evaporation was more obvious than the early successional BSC on stabilized dunes. In general, BSC reduced the amount of rainfall water that reached deeper soil (0.4-3m), which is

  7. Annual monsoon rains recorded by Jurassic dunes.

    Science.gov (United States)

    Loope, D B; Rowe, C M; Joeckel, R M

    2001-07-05

    Pangaea, the largest landmass in the Earth's history, was nearly bisected by the Equator during the late Palaeozoic and early Mesozoic eras. Modelling experiments and stratigraphic studies have suggested that the supercontinent generated a monsoonal atmospheric circulation that led to extreme seasonality, but direct evidence for annual rainfall periodicity has been lacking. In the Mesozoic era, about 190 million years ago, thick deposits of wind-blown sand accumulated in dunes of a vast, low-latitude desert at Pangaea's western margin. These deposits are now situated in the southwestern USA. Here we analyse slump masses in the annual depositional cycles within these deposits, which have been described for some outcrops of the Navajo Sandstone. Twenty-four slumps, which were generated by heavy rainfall, appear within one interval representing 36 years of dune migration. We interpret the positions of 20 of these masses to indicate slumping during summer monsoon rains, with the other four having been the result of winter storms. The slumped lee faces of these Jurassic dunes therefore represent a prehistoric record of yearly rain events.

  8. Vegetation studies on Vandenberg Air Force Base, California

    Science.gov (United States)

    Schmalzer, Paul A.; Hickson, Diana E.; Hinkle, C. Ross

    1988-01-01

    Vandenburg Air Force Base, located in coastal central California with an area of 98,400 ac, contains resources of considerable biological significance. Available information on the vegetation and flora of Vandenburg is summarized and new data collected in this project are presented. A bibliography of 621 references dealing with vegetation and related topics related to Vanderburg was compiled from computer and manual literature searches and a review of past studies of the base. A preliminary floristic list of 642 taxa representing 311 genera and 80 families was compiled from past studies and plants identified in the vegetation sampling conducted in this project. Fifty-two special interest plant species are known to occur or were suggested to occur. Vegetation was sampled using permanent plots and transects in all major plant communities including chaparral, Bishop pine forest, tanbark oak forest, annual grassland, oak woodland, coastal sage scrub, purple sage scrub, coastal dune scrub, coastal dunes, box elder riparian woodland, will riparian woodland, freshwater marsh, salt marsh, and seasonal wetlands. Comparison of the new vegetation data to the compostie San Diego State University data does not indicate major changes in most communities since the original study. Recommendations are made for additional studies needed to maintain and extend the environmental data base and for management actions to improve resource protection.

  9. Quelques noddees sur l’ecologie de la vedetation des dunes et sur la fonction de l’enraciment dans l’edification de dunes a la Cote Mediterraneenne de la France. I

    NARCIS (Netherlands)

    Boterenbrood, A.J.; Donsellaar-Ten Bokkel Huinink, van W.A.E.; Donselaar, van J.

    1956-01-01

    Dans la végétation des dunes du Languedoc J. BRAUN-BLANQUET (1952) distingue trois associations, à savoir; 1) l’Agropyretum mediterraneum parmi et sur les premières dunes basses; 2) l’Ammophiletum arundinaceae sur les dunes plus hautes; et 3) le Crucianelletum maritimae dans les dépressions et en

  10. Impact of Seasonal Hypoxia on Activity and Community Structure of Chemolithoautotrophic Bacteria in a Coastal Sediment.

    Science.gov (United States)

    Lipsewers, Yvonne A; Vasquez-Cardenas, Diana; Seitaj, Dorina; Schauer, Regina; Hidalgo-Martinez, Silvia; Sinninghe Damsté, Jaap S; Meysman, Filip J R; Villanueva, Laura; Boschker, Henricus T S

    2017-05-15

    Seasonal hypoxia in coastal systems drastically changes the availability of electron acceptors in bottom water, which alters the sedimentary reoxidation of reduced compounds. However, the effect of seasonal hypoxia on the chemolithoautotrophic community that catalyzes these reoxidation reactions is rarely studied. Here, we examine the changes in activity and structure of the sedimentary chemolithoautotrophic bacterial community of a seasonally hypoxic saline basin under oxic (spring) and hypoxic (summer) conditions. Combined 16S rRNA gene amplicon sequencing and analysis of phospholipid-derived fatty acids indicated a major temporal shift in community structure. Aerobic sulfur-oxidizing Gammaproteobacteria ( Thiotrichales ) and Epsilonproteobacteria ( Campylobacterales ) were prevalent during spring, whereas Deltaproteobacteria ( Desulfobacterales ) related to sulfate-reducing bacteria prevailed during summer hypoxia. Chemolithoautotrophy rates in the surface sediment were three times higher in spring than in summer. The depth distribution of chemolithoautotrophy was linked to the distinct sulfur oxidation mechanisms identified through microsensor profiling, i.e., canonical sulfur oxidation, electrogenic sulfur oxidation by cable bacteria, and sulfide oxidation coupled to nitrate reduction by Beggiatoaceae The metabolic diversity of the sulfur-oxidizing bacterial community suggests a complex niche partitioning within the sediment, probably driven by the availability of reduced sulfur compounds (H 2 S, S 0 , and S 2 O 3 2- ) and electron acceptors (O 2 and NO 3 - ) regulated by seasonal hypoxia. IMPORTANCE Chemolithoautotrophic microbes in the seafloor are dependent on electron acceptors, like oxygen and nitrate, that diffuse from the overlying water. Seasonal hypoxia, however, drastically changes the availability of these electron acceptors in the bottom water; hence, one expects a strong impact of seasonal hypoxia on sedimentary chemolithoautotrophy. A

  11. Performances d'une nouvelle approche dans l'estimation au champ

    African Journals Online (AJOL)

    ACSS

    Elle possède cependant des limitations, dues à l'organisation temporaire d'une .... Performances d'une nouvelle approche dans l'estimation au champ utilisant le principe de la ... différents types de résidus (soja, luzerne, haricot et maïs) et ...

  12. Impacts of Hurricane Rita on the beaches of western Louisiana: Chapter 5D in Science and the storms-the USGS response to the hurricanes of 2005

    Science.gov (United States)

    Stockdon, Hilary F.; Fauver, Laura A.; Sallenger,, Asbury H.; Wright, C. Wayne

    2007-01-01

    Hurricane Rita made landfall as a category 3 storm in western Louisiana in late September 2005, 1 month following Hurricane Katrina's devastating landfall in the eastern part of the State. Large waves and storm surge inundated the lowelevation coastline, destroying many communities and causing extensive coastal change including beach, dune, and marsh erosion.

  13. On the use of wave parameterizations and a storm impact scaling model in National Weather Service Coastal Flood and decision support operations

    Science.gov (United States)

    Mignone, Anthony; Stockdon, H.; Willis, M.; Cannon, J.W.; Thompson, R.

    2012-01-01

    National Weather Service (NWS) Weather Forecast Offices (WFO) are responsible for issuing coastal flood watches, warnings, advisories, and local statements to alert decision makers and the general public when rising water levels may lead to coastal impacts such as inundation, erosion, and wave battery. Both extratropical and tropical cyclones can generate the prerequisite rise in water level to set the stage for a coastal impact event. Forecasters use a variety of tools including computer model guidance and local studies to help predict the potential severity of coastal flooding. However, a key missing component has been the incorporation of the effects of waves in the prediction of total water level and the associated coastal impacts. Several recent studies have demonstrated the importance of incorporating wave action into the NWS coastal flood program. To follow up on these studies, this paper looks at the potential of applying recently developed empirical parameterizations of wave setup, swash, and runup to the NWS forecast process. Additionally, the wave parameterizations are incorporated into a storm impact scaling model that compares extreme water levels to beach elevation data to determine the mode of coastal change at predetermined “hotspots” of interest. Specifically, the storm impact model compares the approximate storm-induced still water level, which includes contributions from tides, storm surge, and wave setup, to dune crest elevation to determine inundation potential. The model also compares the combined effects of tides, storm surge, and the 2 % exceedance level for vertical wave runup (including both wave setup and swash) to dune toe and crest elevations to determine if erosion and/or ocean overwash may occur. The wave parameterizations and storm impact model are applied to two cases in 2009 that led to significant coastal impacts and unique forecast challenges in North Carolina: the extratropical “Nor'Ida” event during 11-14 November and

  14. The Sources of Moisture in the Sand Dunes – The Example of the Western Sahara Dune Field

    Directory of Open Access Journals (Sweden)

    Żmudzka Elwira

    2014-09-01

    Full Text Available Climatic and meteorological conditions may limit the aeolian transport within barchans. An explanation of that issue was the main goal of the investigation held in Western Sahara dune fields located around Tarfaya and Laâyoune. Particular attention was paid to the factors causing the moisture content rising of the sand dune surface layer, which could influence the wind threshold shear velocity in the aeolian transport. The wetted surface layer of sand, when receiving moisture from precipitation or suspensions, reduces the aeolian transport, even in case of wind velocity above 4-5 m s-1. Fog and dew condensation does not affect the moisture of deeper sand layers, what occurs after rainfall.

  15. Impacts of the Nutrient Inputs from Riverine on the Dynamic and Community Structure of Fungal-like Protists in the Coastal Ocean Ecosystems

    Science.gov (United States)

    Duan, Y.; Wang, G.; Xie, N.

    2016-02-01

    The coastal ocean connects terrestrial (e.g., rivers and estuaries) with oceanic ecosystems and is considered as a major component of global carbon cycles and budgets. The coastal waters are featured with a high biodiversity and high primary production. Because of the excessive primary production, a large fraction of primary organic matter becomes available to consumers as detritus in the coastal waters. Bacterioplankton have long been known to play a key role in the degradation of this detritus, and export and storage of organic matter in the coastal ecosystems. However, the primary and secondary production and the carbon biogeochemical processes in the ecosystems are largely regulated by nutrient inputs from riverine and other anthropogenic activities through heterotrophic microbial communities. Thraustochytrids, commonly known as fungal-like protists, are unicellular heterotrophic protists and are recently acknowledged to play a significant role in ocean carbon cycling. Their abundance exceeds that of bacterioplankton in the most time of the year in the coastal waters of China. Also, their abundance and diversity are largely regulated by nutrients inputs from riverine and other anthropogenic activities. Our findings support that thraustochytrids are a dominant heterotrophic microbial group in the coastal waters. Evidently, thraustochytrids are an import, but neglected, component in microbial carbon biogeochemical processes of the coastal ocean.

  16. Coastal urbanization leads to remarkable seaweed species loss and community shifts along the SW Atlantic.

    Science.gov (United States)

    Scherner, Fernando; Horta, Paulo Antunes; de Oliveira, Eurico Cabral; Simonassi, José Carlos; Hall-Spencer, Jason M; Chow, Fungyi; Nunes, José Marcos C; Pereira, Sonia Maria Barreto

    2013-11-15

    Coastal urbanization is rapidly expanding worldwide while its impacts on seaweed communities remain poorly understood. We assessed the impact of urbanization along an extensive latitudinal gradient encompassing three phycogeographical regions in the SW Atlantic. Human population density, number of dwellings, and terrestrial vegetation cover were determined for each survey area and correlated with diversity indices calculated from seaweed percent cover data. Urban areas had significantly lower calcareous algal cover (-38%), and there was significantly less carbonate in the sediment off urban areas than off reference areas. Seaweed richness averaged 26% less in urban areas than in areas with higher vegetation cover. We observed a remarkable decline in Phaeophyceae and a substantial increase of Chlorophyta in urban areas across a wide latitudinal gradient. Our data show that coastal urbanization is causing substantial loss of seaweed biodiversity in the SW Atlantic, and is considerably changing seaweed assemblages. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Toward a community coastal sediment transport modeling system: the second workshop

    Science.gov (United States)

    Sherwood, Christopher R.; Harris, Courtney K.; Geyer, W. Rockwell; Butman, Bradford

    2002-01-01

    Models for transport and the long-term fate of particles in coastal waters are essential for a variety of applications related to commerce, defense, public health, and the quality of the marine environment. Examples include: analysis of waste disposal and transport and the fate of contaminated materials; evaluation of burial rates for naval mines or archaeological artifacts; prediction of water-column optical properties; analysis of transport and the fate of biological particles; prediction of coastal flooding and coastal erosion; evaluation of impacts of sea-level or wave-climate changes and coastal development; planning for construction and maintenance of navigable waterways; evaluation of habitat for commercial fisheries; evaluation of impacts of natural or anthropogenic changes in coastal conditions on recreational activities; and design of intakes and outfalls for sewage treatment, cooling systems, and desalination plants.

  18. Sedimentary processes of the Bagnold Dunes: Implications for the eolian rock record of Mars.

    Science.gov (United States)

    Ewing, R C; Lapotre, M G A; Lewis, K W; Day, M; Stein, N; Rubin, D M; Sullivan, R; Banham, S; Lamb, M P; Bridges, N T; Gupta, S; Fischer, W W

    2017-12-01

    The Mars Science Laboratory rover Curiosity visited two active wind-blown sand dunes within Gale crater, Mars, which provided the first ground-based opportunity to compare Martian and terrestrial eolian dune sedimentary processes and study a modern analog for the Martian eolian rock record. Orbital and rover images of these dunes reveal terrestrial-like and uniquely Martian processes. The presence of grainfall, grainflow, and impact ripples resembled terrestrial dunes. Impact ripples were present on all dune slopes and had a size and shape similar to their terrestrial counterpart. Grainfall and grainflow occurred on dune and large-ripple lee slopes. Lee slopes were ~29° where grainflows were present and ~33° where grainfall was present. These slopes are interpreted as the dynamic and static angles of repose, respectively. Grain size measured on an undisturbed impact ripple ranges between 50 μm and 350 μm with an intermediate axis mean size of 113 μm (median: 103 μm). Dissimilar to dune eolian processes on Earth, large, meter-scale ripples were present on all dune slopes. Large ripples had nearly symmetric to strongly asymmetric topographic profiles and heights ranging between 12 cm and 28 cm. The composite observations of the modern sedimentary processes highlight that the Martian eolian rock record is likely different from its terrestrial counterpart because of the large ripples, which are expected to engender a unique scale of cross stratification. More broadly, however, in the Bagnold Dune Field as on Earth, dune-field pattern dynamics and basin-scale boundary conditions will dictate the style and distribution of sedimentary processes.

  19. Dune-slope activity due to frost and wind throughout the north polar erg, Mars.

    Science.gov (United States)

    Diniega, Serina; Hansen, Candice J; Allen, Amanda; Grigsby, Nathan; Li, Zheyu; Perez, Tyler; Chojnacki, Matthew

    2017-01-01

    Repeat, high-resolution imaging of dunes within the Martian north polar erg have shown that these dune slopes are very active, with alcoves forming along the dune brink each Mars year. In some areas, a few hundred cubic metres of downslope sand movement have been observed, sometimes moving the dune brink 'backwards'. Based on morphological and activity-timing similarities of these north polar features to southern dune gullies, identifying the processes forming these features is likely to have relevance for understanding the general evolution/modification of dune gullies. To determine alcove-formation model constraints, we have surveyed seven dune fields, each over 1-4 Mars winters. Consistent with earlier reports, we found that alcove-formation activity occurs during the autumn-winter seasons, before or while the stable seasonal frost layer is deposited. We propose a new model in which alcove formation occurs during the autumn, and springtime sublimation activity then enhances the feature. Summertime winds blow sand into the new alcoves, erasing small alcoves over a few Mars years. Based on the observed rate of alcove erasure, we estimated the effective aeolian sand transport flux. From this, we proposed that alcove formation may account for 2-20% of the total sand movement within these dune fields.

  20. Limited Effects of Variable-Retention Harvesting on Fungal Communities Decomposing Fine Roots in Coastal Temperate Rainforests.

    Science.gov (United States)

    Philpott, Timothy J; Barker, Jason S; Prescott, Cindy E; Grayston, Sue J

    2018-02-01

    Fine root litter is the principal source of carbon stored in forest soils and a dominant source of carbon for fungal decomposers. Differences in decomposer capacity between fungal species may be important determinants of fine-root decomposition rates. Variable-retention harvesting (VRH) provides refuge for ectomycorrhizal fungi, but its influence on fine-root decomposers is unknown, as are the effects of functional shifts in these fungal communities on carbon cycling. We compared fungal communities decomposing fine roots (in litter bags) under VRH, clear-cut, and uncut stands at two sites (6 and 13 years postharvest) and two decay stages (43 days and 1 year after burial) in Douglas fir forests in coastal British Columbia, Canada. Fungal species and guilds were identified from decomposed fine roots using high-throughput sequencing. Variable retention had short-term effects on β-diversity; harvest treatment modified the fungal community composition at the 6-year-postharvest site, but not at the 13-year-postharvest site. Ericoid and ectomycorrhizal guilds were not more abundant under VRH, but stand age significantly structured species composition. Guild composition varied by decay stage, with ruderal species later replaced by saprotrophs and ectomycorrhizae. Ectomycorrhizal abundance on decomposing fine roots may partially explain why fine roots typically decompose more slowly than surface litter. Our results indicate that stand age structures fine-root decomposers but that decay stage is more important in structuring the fungal community than shifts caused by harvesting. The rapid postharvest recovery of fungal communities decomposing fine roots suggests resiliency within this community, at least in these young regenerating stands in coastal British Columbia. IMPORTANCE Globally, fine roots are a dominant source of carbon in forest soils, yet the fungi that decompose this material and that drive the sequestration or respiration of this carbon remain largely

  1. The investigation of active Martian dune fields using very high resolution photogrammetric measurements

    Science.gov (United States)

    Kim, Jungrack; Kim, Younghwi; Park, Minseong

    2016-10-01

    At the present time, arguments continue regarding the migration speeds of Martian dune fields and their correlation with atmospheric circulation. However, precisely measuring the spatial translation of Martian dunes has succeeded only a very few times—for example, in the Nili Patera study (Bridges et al. 2012) using change-detection algorithms and orbital imagery. Therefore, in this study, we developed a generic procedure to precisely measure the migration of dune fields with recently introduced 25-cm resolution orbital imagery specifically using a high-accuracy photogrammetric processor. The processor was designed to trace estimated dune migration, albeit slight, over the Martian surface by 1) the introduction of very high resolution ortho images and stereo analysis based on hierarchical geodetic control for better initial point settings; 2) positioning error removal throughout the sensor model refinement with a non-rigorous bundle block adjustment, which makes possible the co-alignment of all images in a time series; and 3) improved sub-pixel co-registration algorithms using optical flow with a refinement stage conducted on a pyramidal grid processor and a blunder classifier. Moreover, volumetric changes of Martian dunes were additionally traced by means of stereo analysis and photoclinometry. The established algorithms have been tested using high-resolution HIRISE time-series images over several Martian dune fields. Dune migrations were iteratively processed both spatially and volumetrically, and the results were integrated to be compared to the Martian climate model. Migrations over well-known crater dune fields appeared to be almost static for the considerable temporal periods and were weakly correlated with wind directions estimated by the Mars Climate Database (Millour et al. 2015). As a result, a number of measurements over dune fields in the Mars Global Dune Database (Hayward et al. 2014) covering polar areas and mid-latitude will be demonstrated

  2. Coastal Structures

    DEFF Research Database (Denmark)

    Oumeraci, H.; Burcharth, H. F.; Rouck, J. De

    1995-01-01

    The paper attempts to present an overview of five research projects supported by the Commission of the European Communities, Directorate General XII, under the MAST 2- Programme (Marine Sciences and Technology), with the overall objective of contributing to the development of improved rational me...... methods for the design of coastal structures....

  3. Sedimentary processes of the Bagnold Dunes: Implications for the eolian rock record of Mars

    OpenAIRE

    Ewing, R. C.; Lapotre, M. G. A.; Lewis, K. W.; Day, M.; Stein, N.; Rubin, D. M.; Sullivan, R.; Banham, S.; Lamb, M. P.; Bridges, N. T.; Gupta, S.; Fischer, W. W.

    2017-01-01

    The Mars Science Laboratory rover Curiosity visited two active wind-blown sand dunes within Gale crater, Mars, which provided the first ground-based opportunity to compare Martian and terrestrial eolian dune sedimentary processes and study a modern analog for the Martian eolian rock record. Orbital and rover images of these dunes reveal terrestrial-like and uniquely Martian processes. The presence of grainfall, grainflow, and impact ripples resembled terrestrial dunes. Impact ripples were pre...

  4. Sedimentary processes of the Bagnold Dunes: Implications for the eolian rock record of Mars

    OpenAIRE

    Ewing, R. C.; Lapotre, M. G. A.; Lewis, K. W.; Day, M.; Stein, N.; Rubin, D. M.; Sullivan, R.; Banham, S.; Lamb, M. P.; Bridges, N. T.; Gupta, S.; Fischer, W. W.

    2017-01-01

    Abstract The Mars Science Laboratory rover Curiosity visited two active wind‐blown sand dunes within Gale crater, Mars, which provided the first ground‐based opportunity to compare Martian and terrestrial eolian dune sedimentary processes and study a modern analog for the Martian eolian rock record. Orbital and rover images of these dunes reveal terrestrial‐like and uniquely Martian processes. The presence of grainfall, grainflow, and impact ripples resembled terrestrial dunes. Impact ripples...

  5. The impacts of tourism on coral reef conservation awareness and support in coastal communities in Belize

    Science.gov (United States)

    Diedrich, A.

    2007-12-01

    Marine recreational tourism is one of a number of threats to the Belize Barrier Reef but, conversely, represents both a motivation and source of resources for its conservation. The growth of tourism in Belize has resulted in the fact that many coastal communities are in varying stages of a socio-economic shift from dependence on fishing to dependence on tourism. In a nation becoming increasingly dependent on the health of its coral reef ecosystems for economic prosperity, a shift from extractive uses to their preservation is both necessary and logical. Through examining local perception data in five coastal communities in Belize, each attracting different levels of coral reef related tourism, this analysis is intended to explore the relationship between tourism development and local coral reef conservation awareness and support. The results of the analysis show a positive correlation between tourism development and coral reef conservation awareness and support in the study communities. The results also show a positive correlation between tourism development and local perceptions of quality of life, a trend that is most likely the source of the observed relationship between tourism and conservation. The study concludes that, because the observed relationship may be dependent on continued benefits from tourism as opposed to a perceived crisis in coral reef health, Belize must pay close attention to tourism impacts in the future. Failure to do this could result in a destructive feedback loop that would contribute to the degradation of the reef and, ultimately, Belize’s diminished competitiveness in the ecotourism market.

  6. Topographically-controlled site conditions drive vegetation pattern on inland dunes in Poland

    Science.gov (United States)

    Sewerniak, Piotr; Jankowski, Michał

    2017-07-01

    The inland dunes of Central Europe are commonly overplanted by Scots pine (Pinus sylvestris) monocultures in which the primary occurrence of the natural vegetation pattern is obliterated. We hypothesize that on naturally revegetated inland dunes the pattern is clear and driven by topographically-controlled site conditions. To test this hypothesis, we addressed the following research questions: (1) Does topography drive vegetation patterns on inland dunes and if so, what are main differences between vegetation in varying relief positions? (2) To what extent does topography involve the variability of microclimates and of soil properties, and how does the topographically-induced differentiation of these site conditions control vegetation patterns? We conducted interdisciplinary studies (applying floristic, pedological and microclimatic research techniques) on a naturally revegetated inland dune area situated on a military artillery training ground near Toruń, northern Poland. We investigated vegetation patterns with reference to three topographical position variants (north-facing slopes, south-facing slopes, and intra-dune depressions). We found distinct differences in vegetation characteristics covering the aforementioned topographical positions. This primarily concerned species composition of ground vegetation: Calluna vulgaris was dominant species on north-facing slopes, Corynephorus canescens on south-facing slopes, while Calamagrostis epigejos in intra-dune depressions. In comparison to dune slopes, the depressions were characterized by much higher biodiversity of vascular plant species. This followed the most favorable soil conditions for the existence of plants (higher moisture and nutrient pools) occurring in low topographical positions. However, tree succession was most advanced not in depressions, where the competitive impact of tall grasses on seedlings was recognized, but on north-facing slopes. Based on our results, we formulated some suggestions, which

  7. Connecting Coastal Communities with Ocean Science: A Look at Ocean Sense and the Inclusion of Place-based Indigenous Knowledge

    Science.gov (United States)

    McLean, M. A.; Brown, J.; Hoeberechts, M.

    2016-02-01

    Ocean Networks Canada (ONC), an initiative of the University of Victoria, develops, operates, and maintains cabled ocean observatory systems. Technologies developed on the world-leading NEPTUNE and VENUS observatories have been adapted for small coastal installations called "community observatories," which enable community members to directly monitor conditions in the local ocean environment. In 2014, ONC pioneered an innovative educational program, Ocean Sense: Local observations, global connections, which introduces students and teachers to the technologies installed on community observatories. The program introduces middle and high school students to research methods in biology, oceanography and ocean engineering through hands-on activities. Ocean Sense includes a variety of resources and opportunities to excite students and spark curiosity about the ocean environment. The program encourages students to connect their local observations to global ocean processes and the observations of students in other geographic regions. The connection to place and local relevance of the program is further enhanced through an emphasis on Indigenous and place-based knowledge. ONC is working with coastal Indigenous communities in a collaborative process to include local knowledge, culture, and language in Ocean Sense materials. For this process to meaningful and culturally appropriate, ONC is relying on the guidance and oversight of Indigenous community educators and knowledge holders. Ocean Sense also includes opportunities for Indigenous youth and teachers in remote communities to connect in person, including an annual Ocean Science Symposium and professional development events for teachers. Building a program which embraces multiple perspectives is effective both in making ocean science more relevant to Indigenous students and in linking Indigenous knowledge and place-based knowledge to ocean science.

  8. Decision-making in Coastal Management and a Collaborative Governance Framework

    Science.gov (United States)

    Over half of the US population lives in coastal watersheds, creating a regional pressure for coastal ecosystems to provide a broad spectrum of services while continuing to support healthy communities and economies. The National Ocean Policy, issued in 2010, and Coastal and Marin...

  9. A study of the dry forest communities in the Dominican Republic.

    Science.gov (United States)

    García-Fuentes, Antonio; Torres-Cordero, Juan A; Ruiz-Valenzuela, Luis; Lendínez-Barriga, María Lucía; Quesada-Rincón, Juan; Valle-Tendero, Francisco; Veloz, Alberto; León, Yolanda M; Salazar-Mendías, Carlos

    2015-03-01

    This paper is a floristic and phytosociological study of the dry forest communities of the Dominican Republic. A total of 69 relevés in dry forest biotopes were carried out. The samples were subsequently subjected to Detrended Correspondence Analysis for the determination and study of possible groupings. The study does not cover tree formations growing on serpentines, nor the so-called semideciduous forests, peculiar to areas with higher rainfall. A total of nine phytocoenoses were identified. The most significant results led to the description of six new phytosociological associations: Simaroubetum berteroani (thorny dry forest on coastal dunes), Phyllostylo rhamnoidis-Prosopidetum juliflorae (southern Dominican disturbed dry forest), Consoleo moniliformis-Camerarietum linearifoliae (dry forest on hard limestones), Lemaireocereo hystricis-Prosopidetum juliflorae (northern Dominican disturbed dry forest), Lycio americani-Prosopidetum juliflorae (disturbed dry forest on saline soils) and Guettardo ellipticae-Guapiretum discoloris (dry forest on flat-topped hillocks in Montecristi). This is an important step forward in the phytosociological and floristic studies of the Caribbean territories.

  10. A study of the dry forest communities in the Dominican Republic

    Directory of Open Access Journals (Sweden)

    Antonio García-Fuentes

    2015-03-01

    Full Text Available This paper is a floristic and phytosociological study of the dry forest communities of the Dominican Republic. A total of 69 relevés in dry forest biotopes were carried out. The samples were subsequently subjected to Detrended Correspondence Analysis for the determination and study of possible groupings. The study does not cover tree formations growing on serpentines, nor the so-called semideciduous forests, peculiar to areas with higher rainfall. A total of nine phytocoenoses were identified. The most significant results led to the description of six new phytosociological associations: Simaroubetum berteroani(thorny dry forest on coastal dunes, Phyllostylo rhamnoidis-Prosopidetum juliflorae (southern Dominican disturbed dry forest, Consoleo moniliformis-Camerarietum linearifoliae(dry forest on hard limestones, Lemaireocereo hystricis-Prosopidetum juliflorae(northern Dominican disturbed dry forest, Lycio americani-Prosopidetum juliflorae (disturbed dry forest on saline soils and Guettardo ellipticae-Guapiretum discoloris (dry forest on flat-topped hillocks in Montecristi. This is an important step forward in the phytosociological and floristic studies of the Caribbean territories.

  11. Pwani Yetu: Issue 4. April 1999.Tanzania Coastal Management Partnership.

    OpenAIRE

    Tanzania Coastal Management Partnership

    1999-01-01

    The Newsletter of the Tanzania Coastal Management Partnership - Pwani Yetu - 'our coast', is produced every other month in both Kiswahili and English and circulated to all coastal management partners from national level, coastal communities and the private sector. Pwani Yetu reports on coastal and marine activities, including issues on conservation, environment, and social economic development. 'Research Group' TCMP.

  12. Modeling the effect of dune sorting on the river long profile

    Science.gov (United States)

    Blom, A.

    2012-12-01

    River dunes, which occur in low slope sand bed and sand-gravel bed rivers, generally show a downward coarsening pattern due to grain flows down their avalanche lee faces. These grain flows cause coarse particles to preferentially deposit at lower elevations of the lee face, while fines show a preference for its upper elevations. Before considering the effect of this dune sorting mechanism on the river long profile, let us first have a look at some general trends along the river profile. Tributaries increasing the river's water discharge in streamwise direction also cause a streamwise increase in flow depth. As under subcritical conditions mean dune height generally increases with increasing flow depth, the dune height shows a streamwise increase, as well. This means that also the standard deviation of bedform height increases in streamwise direction, as in earlier work it was found that the standard deviation of bedform height linearly increases with an increasing mean value of bedform height. As a result of this streamwise increase in standard deviation of dune height, the above-mentioned dune sorting then results in a loss of coarse particles to the lower elevations of the bed that are less and even rarely exposed to the flow. This loss of coarse particles to lower elevations thus increases the rate of fining in streamwise direction. As finer material is more easily transported downstream than coarser material, a smaller bed slope is required to transport the same amount of sediment downstream. This means that dune sorting adds to river profile concavity, compared to the combined effect of abrasion, selective transport and tributaries. A Hirano-type mass conservation model is presented that deals with dune sorting. The model includes two active layers: a bedform layer representing the sediment in the bedforms and a coarse layer representing the coarse and less mobile sediment underneath migrating bedforms. The exposure of the coarse layer is governed by the rate

  13. The Alaska Coastal Communities Cooperative: The concept and feasibility

    International Nuclear Information System (INIS)

    Hann, R.W.

    1992-01-01

    A new initiative is described which further prepares Alaska to deal with oil spills in the future by focusing on the needs of shoreline protection and nearshore response. The Alaskan Coastal Communities Cooperative (ACCC) has been formed to organize local resources and provide appropriate training, equipment, and coordination to deal with both small spills, local product spills, and catastrophic spills. Advantages of the ACCC to industry and governments include a significant enhancement of oil spill response capability in Alaska. For example, the ACCC will ensure that the response equipment it acquires is compatible with existing resources, thus creating maximum response capability at minimum cost. Other advantages include greater public trust, low costs, ability to provide a combination of local knowledge and technical knowledge, provision of a pooling of spill response resources, and the ability of the ACCC to handle contracting of local fishing and other vessels used in oil spill response. The ACCC organizational structure and vessel contracting program are described along with its equipment and operating format. 1 fig

  14. Mangrove Cultivation For Dealing With Coastal Abrasion Case Study Of Karangsong

    Science.gov (United States)

    Fatimatuzzahroh, Feti; Hadi, Sudharto P.; Purnaweni, Hartuti

    2018-02-01

    Coastal abrasion is consequence from destructive waves and sea current. One of cause is human intervention. The effort to solve of abrasion is by mangrove cultivation. Mangroves are halophyte plant that can restrain the sea wave. Mangrove cultivation required participation community that give awareness the importance of mangrove in coastal sustainability. Mangroves in coastal Karangsong, Indramayu west java, in 2007 was through abrasion approximately 127.30 ha. Mangrove cultivation in Karangsong has been replanting since 1998 to 2003, but there was no maintenance and management. In 2007 until 2015 Karangsong replanting mangroves and has been succeed. Karangsong became the center of mangrove study for west java area in 2015. This achievement is result of cooperation between community, NGO, and local government. In addition, this effort made not only overcome the abrasion problem but also give community awareness about the importance of mangrove cultivation in preventing coastal abrasion throughout community development. This paper reviews abrasion in Karangsong and the impact for local community and empowerment in mangrove cultivation. To achieve the success mangrove cultivation required community development approach from planning process, planting, maintenance and management.

  15. Coastal zone: Shelf-EEZ and land sea interface

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, B.N.; Parulekar, A

    Among the few vibrant ecotopes is the coastal zone, where multifaceted interactions among air, sea and land are dynamically balanced. An area of intense clash of interest of user community, the coastal zone harbouring vast potential of renewable...

  16. SHEAR STRENGTH, COLLAPSIBILITY AND COMPRESSIBILITY CHARACTERISTICS OF COMPACTED BAIJI DUNE SOILS

    Directory of Open Access Journals (Sweden)

    ABBAS JAWAD AL-TAIE

    2017-03-01

    Full Text Available Baiji city is a vital industrial centre in Iraq since it has the biggest oil refinery. Therefore, Baiji has become an attractive site for strategic construction projects. Dune sand covers about 220 km2 of the area of Baiji city. However, few researches had attempted to study its behaviour. In this study laboratory tests were conducted to determine the shear strength, collapsibility and compressibility of the dune sand at its natural and compacted status. The effect of dry unit weight, moisture content, relative density and soaking on mechanical properties of dune soil was investigated. The results demonstrated that dry and soaked dune specimens tested at their in-situ condition exhibited similar volume changes during shear and identical friction angles. The results of shear tests of both of compacted soaked and unsoaked samples were identical. The collapse potential of dune soil is inversely proportional with the relative density. The minimum axial strain is observed when the samples are compacted to modified effort. The compression index of the compacted specimens is affected by moulding water content, while the rebound index is less sensitive.

  17. The morphodynamics and internal structure of intertidal fine-gravel dunes: Hills Flats, Severn Estuary, UK

    Science.gov (United States)

    Carling, P. A.; Radecki-Pawlik, A.; Williams, J. J.; Rumble, B.; Meshkova, L.; Bell, P.; Breakspear, R.

    2006-01-01

    In the macrotidal Severn estuary, UK, the dynamics of intertidal fine-gravel dunes were investigated. These dunes are migrating across a bedrock platform. Systematic observations were made of hydraulic climate, geometry, migration rates and internal sedimentary structures of the dunes. During spring tides, the ebb flow is dominant, dunes grow in height and have ebb orientated geometry with bedrock floors in the troughs. During neap tides, a weak flood flow may dominate. Dunes then are flood orientated or symmetrical. Neap dune heights decrease and the eroded sediment is stored in the dune troughs where the bedrock becomes blanketed by muddy gravel. During spring tides, instantaneous bed shear stresses reach 8 N m - 2 , sufficient to disrupt a 9 mm-gravel armour layer. However, a sustained bed shear stress of 4 N m - 2 is required to initiate dune migration at which time the critical depth-mean velocity is 1 m s - 1 . Ebb and flood inequalities in the bed shear stress explain the changes in dune asymmetry and internal structures. During flood tides, the crests of the dunes reverse such that very mobile sedimentary 'caps' overlie a more stable dune 'core'. Because ebb tides dominate, internal structures of the caps often are characterised by ebb orientated steep open-work foresets developed by strong tidal currents and some lower angle crossbeds deposited as weaker currents degrade foresets. The foresets forming the caps may be grouped into cosets (tidal bundles) and are separated from mud-infused cores of crossbeds that lie below, by reactivation and erosion surfaces blanketed by discontinuous mud drapes. The cores often exhibit distinctive muddy toe sets that define the spacing of tidal cosets.

  18. CFD evaluation of erosion rate around a bridge near a sand dune

    Science.gov (United States)

    He, Wei; Huang, Ning; Dun, Hongchao; Wang, Wenbo

    2017-04-01

    This study performs a series of simulations through solving the Navier-Stokes equations and the RNG k-ε turbulence model to investigate the wind erosion rates around a bridge in a desert area with sand dunes. The digital elevation model of sand dunes and the bridge model are obtained respectively from hypsographic map and construction drawings. Through combining them into the CFD software of Fluent the simulation zone was formed. The data of wind speed obtained from field observation is fitted into a logarithm format, which was imported into Fluent model as a inlet wind speed condition. Then, the effect of Dun-Go railway on wind-blown sand movement of the neighbouring environment is simulated. The results exhibit that affected by both the sand dune and bridge, the flow field is in a complex condition. It is also shown that the bridge in upstream of the sand dune will not increase the sand transport rate intensively, but change both wind velocity gradient and turbulence kinetic energy over surface of sand dune. On the other hand, when the bridge is built downstream the sand dune, simulation results show that sand deposition rate would be decreased in reference region downstream the pier.

  19. Parabolic dune development modes according to shape at the southern fringes of the Hobq Desert, Inner Mongolia, China

    Science.gov (United States)

    Guan, Chao; Hasi, Eerdun; Zhang, Ping; Tao, Binbin; Liu, Dan; Zhou, Yanguang

    2017-10-01

    Since the 1970s, parabolic dunes at the southern fringe of the Hobq Desert, Inner Mongolia, China have exhibited many different shapes (V-shaped, U-shaped, and palmate) each with a unique mode of development. In the study area, parabolic dunes are mainly distributed in Regions A, B, and C with an intermittent river running from the south to the north. We used high-resolution remote-sensing images from 1970 to 2014 and RTK-GPS measurements to study the development modes of different dune shapes; the modes are characterized by the relationship between the intermittent river and dunes, formation of the incipient dune patterns, the predominant source supply of dunes, and the primary formation of different shapes (V-shaped, U-shaped, and palmate). Most parabolic dunes in Region A are V-shaped and closer to the bank of the river. The original barchans in this region exhibit "disconnected arms" behavior. With the sand blown out of the riverbed through gullies, the nebkhas on the disconnected arms acquire the external sand source through the "fertile island effect", thereby developing into triangular sand patches and further developing into V-shaped parabolic dunes. Most parabolic dunes in Regions B and C are palmate. The residual dunes cut by the re-channelization of river from transverse dune fields on the west bank are the main sand source of Region B. The parabolic dunes in Region C are the original barchans having then been transformed. The stoss slopes of V-shaped parabolic dunes along the riverbank are gradual and the dunes are flat in shape. The dune crest of V-shaped parabolic dune is the deposition area, which forms the "arc-shaped sand ridge". Their two arms are non-parallel; the lateral airflow of the arms jointly transport sand to the middle part of dunes, resulting in a narrower triangle that gradually becomes V-shaped. Palmate parabolic dunes have a steeper stoss slope and height. The dune crest of the palmate parabolic dune is the erosion area, which forms

  20. Demography and monitoring of Welsh's milkweed (Asclepias welshii) at Coral Pink Sand Dunes

    Science.gov (United States)

    Brent C. Palmer; L. Armstrong

    2001-01-01

    Results are presented of a 12-year monitoring program on the Coral Pink Sand Dunes and Sand Hills populations of the threatened Welsh's milkweed, Asclepias welshii N & P Holmgren. The species is an early sera1 member of the dune flora, colonizing blowouts and advancing with shifting dunes. When an area stabilizes and other vegetation encroaches, A. welshii is...