WorldWideScience

Sample records for mexico coastal wetlands

  1. Coastal Wetland Ecosystem Responses to Climate Change: the Role of Macroclimatic Drivers along the Northern Gulf of Mexico

    Science.gov (United States)

    Osland, M. J.; Enwright, N.; Day, R. H.; Gabler, C. A.; Stagg, C. L.; From, A. S.

    2014-12-01

    Across the globe, macroclimatic drivers greatly influence coastal wetland ecosystem structure and function. However, changing macroclimatic conditions are rarely incorporated into coastal wetland vulnerability assessments. Here, we quantify the influence of macroclimatic drivers upon coastal wetland ecosystems along the Northern Gulf of Mexico (NGOM) coast. From a global perspective, the NGOM coast provides several excellent opportunities to examine the effects of climate change upon coastal wetlands. The abundant coastal wetland ecosystems in the region span two major climatic gradients: (1) a winter temperature gradient that crosses temperate to tropical climatic zones; and (2) a precipitation gradient that crosses humid to semi-arid zones. We present analyses where we used geospatial data (historical climate, hydrology, and coastal wetland coverage) and field data (soil, elevation, and plant community composition and structure) to quantify climate-mediated ecological transitions. We identified winter climate and precipitation-based thresholds that separate mangrove forests from salt marshes and vegetated wetlands from unvegetated wetlands, respectively. We used simple distribution and abundance models to evaluate the potential ecological effects of alternative future climate change scenarios. Our results illustrate and quantify the importance of macroclimatic drivers and indicate that climate change could result in landscape-scale changes in coastal wetland ecosystem structure and function. These macroclimate-mediated ecological changes could affect the supply of some ecosystem goods and services as well as the resilience of these ecosystems to stressors, including accelerated sea level rise. Collectively, our findings highlight the importance of incorporating macroclimatic drivers within future-focused coastal wetland vulnerability assessments.

  2. Carbon Sequestration in Wetland Soils of the Northern Gulf of Mexico Coastal Region

    Science.gov (United States)

    Coastal wetlands play an important but complex role in the global carbon cycle, contributing to the ecosystem service of greenhouse gas regulation through carbon sequestration. Although coastal wetlands occupy a small percent of the total US land area, their potential for carbon...

  3. ENVIRONMENTAL EFFECTS OF A GOLF COMPLEX ON COASTAL WETLANDS IN THE GULF OF MEXICO

    Science.gov (United States)

    The increasing density of golf courses represents a potential source of contamination to nearby coastal wetlands and other near-shore areas. The chemical and biological magnitude of the problem is almost unknown. To provide perspective on this issue, the effects of golf complex r...

  4. Coastal Wetland Restoration Bibliography

    National Research Council Canada - National Science Library

    Yozzo, David

    1997-01-01

    This bibliography was compiled to provide biologists, engineers, and planners at Corps Districts and other agencies/ institutions with a guide to the diverse body of literature on coastal wetland restoration...

  5. Assessing coastal wetland vulnerability to sea-level rise along the northern Gulf of Mexico coast: Gaps and opportunities for developing a coordinated regional sampling network.

    Science.gov (United States)

    Osland, Michael J; Griffith, Kereen T; Larriviere, Jack C; Feher, Laura C; Cahoon, Donald R; Enwright, Nicholas M; Oster, David A; Tirpak, John M; Woodrey, Mark S; Collini, Renee C; Baustian, Joseph J; Breithaupt, Joshua L; Cherry, Julia A; Conrad, Jeremy R; Cormier, Nicole; Coronado-Molina, Carlos A; Donoghue, Joseph F; Graham, Sean A; Harper, Jennifer W; Hester, Mark W; Howard, Rebecca J; Krauss, Ken W; Kroes, Daniel E; Lane, Robert R; McKee, Karen L; Mendelssohn, Irving A; Middleton, Beth A; Moon, Jena A; Piazza, Sarai C; Rankin, Nicole M; Sklar, Fred H; Steyer, Greg D; Swanson, Kathleen M; Swarzenski, Christopher M; Vervaeke, William C; Willis, Jonathan M; Wilson, K Van

    2017-01-01

    Coastal wetland responses to sea-level rise are greatly influenced by biogeomorphic processes that affect wetland surface elevation. Small changes in elevation relative to sea level can lead to comparatively large changes in ecosystem structure, function, and stability. The surface elevation table-marker horizon (SET-MH) approach is being used globally to quantify the relative contributions of processes affecting wetland elevation change. Historically, SET-MH measurements have been obtained at local scales to address site-specific research questions. However, in the face of accelerated sea-level rise, there is an increasing need for elevation change network data that can be incorporated into regional ecological models and vulnerability assessments. In particular, there is a need for long-term, high-temporal resolution data that are strategically distributed across ecologically-relevant abiotic gradients. Here, we quantify the distribution of SET-MH stations along the northern Gulf of Mexico coast (USA) across political boundaries (states), wetland habitats, and ecologically-relevant abiotic gradients (i.e., gradients in temperature, precipitation, elevation, and relative sea-level rise). Our analyses identify areas with high SET-MH station densities as well as areas with notable gaps. Salt marshes, intermediate elevations, and colder areas with high rainfall have a high number of stations, while salt flat ecosystems, certain elevation zones, the mangrove-marsh ecotone, and hypersaline coastal areas with low rainfall have fewer stations. Due to rapid rates of wetland loss and relative sea-level rise, the state of Louisiana has the most extensive SET-MH station network in the region, and we provide several recent examples where data from Louisiana's network have been used to assess and compare wetland vulnerability to sea-level rise. Our findings represent the first attempt to examine spatial gaps in SET-MH coverage across abiotic gradients. Our analyses can be used

  6. Assessing coastal wetland vulnerability to sea-level rise along the northern Gulf of Mexico coast: Gaps and opportunities for developing a coordinated regional sampling network.

    Directory of Open Access Journals (Sweden)

    Michael J Osland

    Full Text Available Coastal wetland responses to sea-level rise are greatly influenced by biogeomorphic processes that affect wetland surface elevation. Small changes in elevation relative to sea level can lead to comparatively large changes in ecosystem structure, function, and stability. The surface elevation table-marker horizon (SET-MH approach is being used globally to quantify the relative contributions of processes affecting wetland elevation change. Historically, SET-MH measurements have been obtained at local scales to address site-specific research questions. However, in the face of accelerated sea-level rise, there is an increasing need for elevation change network data that can be incorporated into regional ecological models and vulnerability assessments. In particular, there is a need for long-term, high-temporal resolution data that are strategically distributed across ecologically-relevant abiotic gradients. Here, we quantify the distribution of SET-MH stations along the northern Gulf of Mexico coast (USA across political boundaries (states, wetland habitats, and ecologically-relevant abiotic gradients (i.e., gradients in temperature, precipitation, elevation, and relative sea-level rise. Our analyses identify areas with high SET-MH station densities as well as areas with notable gaps. Salt marshes, intermediate elevations, and colder areas with high rainfall have a high number of stations, while salt flat ecosystems, certain elevation zones, the mangrove-marsh ecotone, and hypersaline coastal areas with low rainfall have fewer stations. Due to rapid rates of wetland loss and relative sea-level rise, the state of Louisiana has the most extensive SET-MH station network in the region, and we provide several recent examples where data from Louisiana's network have been used to assess and compare wetland vulnerability to sea-level rise. Our findings represent the first attempt to examine spatial gaps in SET-MH coverage across abiotic gradients. Our

  7. From Ecosystem-Scale to Litter Biochemistry: Controls on Carbon Sequestration in Coastal Wetlands of the Western Gulf of Mexico

    Science.gov (United States)

    Louchouarn, P.; Kaiser, K.; Norwood, M. J.; Sterne, A. M. E.; Armitage, A. R.; HighField, W.; Brody, S.

    2015-12-01

    Landscape-level shifts in plant species distribution and abundance can fundamentally change the structure and services of an ecosystem. Such shifts are occurring within mangrove-marsh ecotones of the U.S., where over the last few decades, relatively mild winters have led to mangrove expansion into areas previously occupied by salt marsh plants. Here we present the synthesis of 3 years of multidisciplinary work to quantify ecosystem shifts at the regional scale, along the entire Texas (USA) coast of the western Gulf of Mexico, and transcribe these shifts into carbon (C) sequestration mass balances. We classified Landsat-5 Thematic Mapper images using artificial neural networks to quantify shifts in areal coverage of black mangrove (Avicennia germinans) and salt marsh (Spartina alterniflora and other grass and forb species) over 20 years across the Texas Gulf coast. Between 1990 and 2010, mangrove area expanded by 74% (+16 km2). Concurrently, salt marsh area experienced a net loss of 24% (-78 km2). Most of that loss was due to conversion to tidal flats or water, likely a result of relative sea level rise, with only 6% attributable to mangrove expansion. Although relative carbon load (per surface area) are statistically larger for mangrove wetlands, total C loads are larger for salt marsh wetlands due to their greater aerial coverage. The entire loss of above ground C (~7.0·109 g), was offset by salt marsh expansion (2.0·109 g) and mangrove expansion (5.6·109 g) over the study period. Concurrently, the net loss in salt marsh coverage led to a loss in below ground C accumulation capacity of 2.0·109 g/yr, whereas the net expansion of mangrove wetlands led to an added below ground C accumulation capacity of 0.4·109 g/yr. Biomarker data show that neutral carbohydrates and lignin contributed 30-70% and 10-40% of total C, respectively, in plant litter and surface sediments. Sharp declines of carbohydrate yields with depth occur parallel to increases in lignin

  8. Macroclimatic change expected to transform coastal wetland ecosystems this century

    Science.gov (United States)

    Gabler, Christopher A.; Osland, Michael J.; Grace, James B.; Stagg, Camille L.; Day, Richard H.; Hartley, Stephen B.; Enwright, Nicholas M.; From, Andrew S.; McCoy, Meagan L.; McLeod, Jennie L.

    2017-01-01

    Coastal wetlands, existing at the interface between land and sea, are highly vulnerable to climate change. Macroclimate (for example, temperature and precipitation regimes) greatly influences coastal wetland ecosystem structure and function. However, research on climate change impacts in coastal wetlands has concentrated primarily on sea-level rise and largely ignored macroclimatic drivers, despite their power to transform plant community structure and modify ecosystem goods and services. Here, we model wetland plant community structure based on macroclimate using field data collected across broad temperature and precipitation gradients along the northern Gulf of Mexico coast. Our analyses quantify strongly nonlinear temperature thresholds regulating the potential for marsh-to-mangrove conversion. We also identify precipitation thresholds for dominance by various functional groups, including succulent plants and unvegetated mudflats. Macroclimate-driven shifts in foundation plant species abundance will have large effects on certain ecosystem goods and services. Based on current and projected climatic conditions, we project that transformative ecological changes are probable throughout the region this century, even under conservative climate scenarios. Coastal wetland ecosystems are functionally similar worldwide, so changes in this region are indicative of potential future changes in climatically similar regions globally.

  9. Spatial variability of coastal wetland resilience to sea-level rise using Bayesian inference

    Science.gov (United States)

    Hardy, T.; Wu, W.

    2017-12-01

    The coastal wetlands in the Northern Gulf of Mexico (NGOM) account for 40% of coastal wetland area in the United States and provide various ecosystem services to the region and broader areas. Increasing rates of relative sea-level rise (RSLR), and reduced sediment input have increased coastal wetland loss in the NGOM, accounting for 80% of coastal wetland loss in the nation. Traditional models for predicting the impact of RSLR on coastal wetlands in the NGOM have focused on coastal erosion driven by geophysical variables only, and/or at small spatial extents. Here we developed a model in Bayesian inference to make probabilistic prediction of wetland loss in the entire NGOM as a function of vegetation productivity and geophysical attributes. We also studied how restoration efforts help maintain the area of coastal wetlands. Vegetation productivity contributes organic matter to wetland sedimentation and was approximated using the remotely sensed normalized difference moisture index (NDMI). The geophysical variables include RSLR, tidal range, river discharge, coastal slope, and wave height. We found a significantly positive relation between wetland loss and RSLR, which varied significantly at different river discharge regimes. There also existed a significantly negative relation between wetland loss and NDMI, indicating that in-situ vegetation productivity contributed to wetland resilience to RSLR. This relation did not vary significantly between river discharge regimes. The spatial relation revealed three areas of high RSLR but relatively low wetland loss; these areas were associated with wetland restoration projects in coastal Louisiana. Two projects were breakwater projects, where hard materials were placed off-shore to reduce wave action and promote sedimentation. And one project was a vegetation planting project used to promote sedimentation and wetland stabilization. We further developed an interactive web tool that allows stakeholders to develop similar wetland

  10. Lake Superior Coastal Wetland Fish Assemblages and ...

    Science.gov (United States)

    The role of the coastal margin and the watershed context in defining the ecology of even very large lakes is increasingly being recognized and examined. Coastal wetlands are both important contributors to the biodiversity and productivity of large lakes and important mediators of the lake-basin connection. We explored wetland-watershed connections and their relationship to wetland function and condition using data collected from 37 Lake Superior wetlands spanning a substantial geographic and geomorphic gradient. While none of these wetlands are particularly disturbed, there were nevertheless clear relationships between watershed landuse and wetland habitat and biota, and these varied consistently across wetland type categories that reflected the strength of connection to the watershed. For example, water clarity and vegetation structure complexity declined with decreasing percent natural land cover, and these effects were strongest in riverine wetlands (having generally large watersheds and tributary-dominated hydrology) and weakest in lagoon wetlands (having generally small watersheds and lake-dominate hydrology). Fish abundance and species richness both increased with decreasing percent natural land cover while species diversity decreased, and again the effect was strongest in riverine wetlands. Lagoonal wetlands, which lack any substantial tributary, consistently harbored the fewest species of fish and a composition different from the more watershed-lin

  11. Coastal wetlands: an integrated ecosystem approach

    Science.gov (United States)

    Perillo, G. M. E.; Wolanski, E.; Cahoon, D.R.; Brinson, M.M.

    2009-01-01

    Coastal wetlands are under a great deal of pressure from the dual forces of rising sea level and the intervention of human populations both along the estuary and in the river catchment. Direct impacts include the destruction or degradation of wetlands from land reclamation and infrastructures. Indirect impacts derive from the discharge of pollutants, changes in river flows and sediment supplies, land clearing, and dam operations. As sea level rises, coastal wetlands in most areas of the world migrate landward to occupy former uplands. The competition of these lands from human development is intensifying, making the landward migration impossible in many cases. This book provides an understanding of the functioning of coastal ecosystems and the ecological services that they provide, and suggestions for their management. In this book a CD is included containing color figures of wetlands and estuaries in different parts of the world.

  12. A New View of Glacial Age Coastal Wetlands from A Well-Preserved Underwater Baldcypress Forest in the Northern Gulf of Mexico

    Science.gov (United States)

    DeLong, K. L.; Harley, G. L.; Bentley, S. J.; Xu, K.; Reese, A.; Caporaso, A.; Obelcz, J.; Gonzalez Rodriguez, S. M.; Truong, J. T.; Shen, Z.; Raines, B.

    2017-12-01

    presence of robust subtropical coastal wetlands during the glacial interval; however, environmental stress decreased tree growth and sea level rise ultimately buried the forest. This site is yielding valuable information on glacial age environments, coastal geomorphology, sediment preservation of macro botanicals, and many other scientific questions.

  13. Coastal wetland adaptation to sea level rise: Quantifying potential for landward migration and coastal squeeze

    Science.gov (United States)

    Borchert, Sinéad M.; Osland, Michael J.; Enwright, Nicholas M.; Griffith, Kereen

    2018-01-01

    Coastal wetland ecosystems are expected to migrate landwards in response to rising seas. However, due to differences in topography and coastal urbanization, estuaries vary in their ability to accommodate migration. Low‐lying urban areas can constrain migration and lead to wetland loss (i.e. coastal squeeze), especially where existing wetlands cannot keep pace with rising seas via vertical adjustments. In many estuaries, there is a pressing need to identify landward migration corridors and better quantify the potential for landward migration and coastal squeeze.We quantified and compared the area available for landward migration of tidal saline wetlands and the area where urban development is expected to prevent migration for 39 estuaries along the wetland‐rich USA Gulf of Mexico coast. We did so under three sea level rise scenarios (0.5, 1.0, and 1.5 m by 2100).Within the region, the potential for wetland migration is highest within certain estuaries in Louisiana and southern Florida (e.g. Atchafalaya/Vermilion Bays, Mermentau River, Barataria Bay, and the North and South Ten Thousand Islands estuaries).The potential for coastal squeeze is highest in estuaries containing major metropolitan areas that extend into low‐lying lands. The Charlotte Harbor, Tampa Bay, and Crystal‐Pithlachascotee estuaries (Florida) have the highest amounts of urban land expected to constrain wetland migration. Urban barriers to migration are also high in the Galveston Bay (Texas) and Atchafalaya/Vermilion Bays (Louisiana) estuaries.Synthesis and applications. Coastal wetlands provide many ecosystem services that benefit human health and well‐being, including shoreline protection and fish and wildlife habitat. As the rate of sea level rise accelerates in response to climate change, coastal wetland resources could be lost in areas that lack space for landward migration. Migration corridors are particularly important in highly urbanized estuaries where, due to low‐lying coastal

  14. Village Dogs in Coastal Mexico

    NARCIS (Netherlands)

    Ruiz Izaguirre, Eliza; Hebinck, P.G.M.; Eilers, C.H.A.M.

    2018-01-01

    Village dogs are important for households in coastal Mexico, yet they are seen as out of place by etic stakeholders (public health and wildlife experts, and animal welfarists). Caregivers of village dogs are considered irresponsible, a view that is reinforced by Mexican policy. We describe two

  15. 2011 Summary: Coastal wetland restoration research

    Science.gov (United States)

    Kowalski, Kurt P.; Wiley, Michael J.; Wilcox, Douglas A.; Carlson Mazur, Martha L.; Czayka, Alex; Dominguez, Andrea; Doty, Susan; Eggleston, Mike; Green, Sean; Sweetman, Amanda

    2014-01-01

    The Great Lakes Restoration Initiative (GLRI) projects currently taking place in Great Lakes coastal wetlands provide a unique opportunity to study ecosystem response to management actions as practitioners strive to improve wetland function and increase ecosystem services. Through a partnership between the U.S. Geological Survey – Great Lakes Science Center (GLSC), U.S. Fish and Wildlife Service (USFWS), and Ducks Unlimited, a GLRI-funded project has reestablished the hydrologic connection between an intensively managed impounded wetland (Pool 2B) and Crane Creek, a small Lake Erie tributary, by building a water-control structure that was opened in the spring of 2011. The study site is located within the USFWS Ottawa National Wildlife Refuge (ONWR) and lies within the boundaries of the U.S. Environmental Protection Agency (EPA)-designated Maumee River Area of Concern. The broad objective of the project is to evaluate how hydrologically reconnecting a previously diked wetland impacts fish, mollusks, and other biota and affects nutrient transport, nutrient cycling, water quality, flood storage, and many other abiotic conditions. The results from this project suggest large system-wide benefits from sustainable reestablishment of lake-driven hydrology in this and other similar systems. We comprehensively sampled water chemistry, fish, birds, plants, and invertebrates in Crane Creek coastal wetlands, Pool 2A (a reference diked wetland), and Pool 2B (the reconnected wetland) in 2010 and 2011 to: 1) Characterize spatial and seasonal patterns for these parameters. 2) Examine ecosystem response to the opening of a water-control structure that allows fish passage Our sampling efforts have yielded data that reveal striking changes in water quality, hydrology, and fish assemblages in our experimental unit (2B). Prior to the reconnection, the water chemistry in pools 2A and 2B were very similar. Afterwards, we found that the water chemistry in reconnected Pool 2B was more

  16. Biodiversity studies in three Coastal Wetlands in Ghana, West Africa ...

    African Journals Online (AJOL)

    Plant biodiversity studies of three coastal wetlands in Ghana were made. The wetlands are the Sakumo, Muni-Pomadze and Densu Delta Ramsar sites. Each wetland is made up of a flood plain which consists of salt marsh (about 20%), mangrove swamps (between 15 and 30%), fresh water swamp (about 40 - 45%), and in ...

  17. Tidal Wetlands and Coastal Ocean Carbon Dynamics

    Science.gov (United States)

    Hopkinson, C.; Wang, S. R.; Forbrich, I.; Giblin, A. E.; Cai, W. J.

    2017-12-01

    Recent overviews of coastal ocean C dynamics have tidal wetlands in a prominent position: a local sink for atmospheric CO2, a local store of OC, and a source of DIC and OC for the adjacent estuary and nearshore ocean. Over the past decade there have been great strides made in quantifying and understanding these flows and linkages. GPP and R of the wetlands are not nearly as imbalanced as thought 30 yrs ago. Heterotrophy of adjacent estuarine waters is not solely due to the respiration of OC exported from the marsh, rather we see the marsh directly respiring into the water during tidal inundation and accumulated marsh DIC draining into tidal creeks. Organic carbon burial on the marsh is still a relatively minor flux, but it is large relative to marsh NEE. Using literature and unpublished data on marsh DIC export, we used examples from Sapelo Island GA USA and Plum Island MA USA to constrain estimates of NEP and potential OC export. P. There remain large uncertainties in quantifying C dynamics of coupled wetland - estuary systems. Gas exchange from the water to atmosphere is one of the largest uncertainties. Work at Sapelo suggests that upwards of 40% of all daily exchange occurs from water flooding the marsh, which is but a few hours a day. This estimate is based on the intercept value for gas exchange vs wind velocity. Another major uncertainty comes from converting between O2 based estimates of metabolism to C. At Sapelo we find PQ and RQ values diverging greatly from Redfield. Finally, C dynamics of the coastal ocean, especially the role of tidal wetlands is likely to change substantially in the future. Studies at Plum Island show a reversal of the 4000 yr process of marsh progradation with marshes eroding away at their edges because of inadequate sediment supply and rising sea level. The fate of eroded OC is questionable. Landward transgression with SLR is the only likely counter to continued wetland loss - but that's a complex social issue requiring new

  18. Resilience of coastal wetlands to extreme hydrologicevents in Apalachicola Bay

    Science.gov (United States)

    Medeiros, S. C.; Singh, A.; Tahsin, S.

    2017-12-01

    Extreme hydrologic events such as hurricanes and droughts continuously threaten wetlands which provide key ecosystem services in coastal areas. The recovery time for vegetation after impact fromthese extreme events can be highly variable depending on the hazard type and intensity. Apalachicola Bay in Florida is home to a rich variety of saltwater and freshwater wetlands and is subject to a wide rangeof hydrologic hazards. Using spatiotemporal changes in Landsat-based empirical vegetation indices, we investigate the impact of hurricane and drought on both freshwater and saltwater wetlands from year 2000to 2015 in Apalachicola Bay. Our results indicate that saltwater wetlands are more resilient than freshwater wetlands and suggest that in response to hurricanes, the coastal wetlands took almost a year to recover,while recovery following a drought period was observed after only a month.

  19. Freshwater availability and coastal wetland foundation species: ecological transitions along a rainfall gradient

    Science.gov (United States)

    Osland, Michael J.; Enwright, Nicholas M.; Stagg, Camille L.

    2014-01-01

    Climate gradient-focused ecological research can provide a foundation for better understanding critical ecological transition points and nonlinear climate-ecological relationships, which is information that can be used to better understand, predict, and manage ecological responses to climate change. In this study, we examined the influence of freshwater availability upon the coverage of foundation plant species in coastal wetlands along a northwestern Gulf of Mexico rainfall gradient. Our research addresses the following three questions: (1) what are the region-scale relationships between measures of freshwater availability (e.g., rainfall, aridity, freshwater inflow, salinity) and the relative abundance of foundation plant species in tidal wetlands; (2) How vulnerable are foundation plant species in tidal wetlands to future changes in freshwater availability; and (3) What is the potential future relative abundance of tidal wetland foundation plant species under alternative climate change scenarios? We developed simple freshwater availability-based models to predict the relative abundance (i.e., coverage) of tidal wetland foundation plant species using climate data (1970-2000), estuarine freshwater inflow-focused data, and coastal wetland habitat data. Our results identify regional ecological thresholds and nonlinear relationships between measures of freshwater availability and the relative abundance of foundation plant species in tidal wetlands. In drier coastal zones, relatively small changes in rainfall could produce comparatively large landscape-scale changes in foundation plant species abundance which would affect some ecosystem good and services. Whereas a drier future would result in a decrease in the coverage of foundation plant species, a wetter future would result in an increase in foundation plant species coverage. In many ways, the freshwater-dependent coastal wetland ecological transitions we observed are analogous to those present in dryland

  20. Taxonomic Report on Small Mammals from Two Coastal Wetland ...

    African Journals Online (AJOL)

    Fiifi Baidoo

    Abstract. Surveys of the small mammal populations of two coastal wetlands in Ghana, .... Captured animals were euthanized with chloroform, according to the American Society of. Mammalogy Animal Care and Use Committee guidelines.

  1. Methane emissions from different coastal wetlands in New England, US

    Science.gov (United States)

    Wang, F.; Tang, J.; Kroeger, K. D.; Gonneea, M. E.

    2017-12-01

    According to the IPCC, methane have 25 times warming effect than CO2, and natural wetlands contribute 20-39 % to the global emission of methane. Although most of these methane was from inland wetlands, there was still large uncertain in the methane emissions in coastal wetlands. In the past three years, we have investigated methane emissions in coastal wetlands in MA, USA. Contrary to previous assumptions, we have observed relative larger methane flux in some salt marshes than freshwater wetlands. We further detect the methane source, and found that plant activities played an important role in methane flux, for example, the growth of S. aterniflora, the dominate plants in salt marsh, could enhance methane emission, while in an fresh water wetland that was dominated by cattail, plant activity oxided methane and reduced total flux. Phragmite, an invasive plant at brackish marsh, have the highest methane flux among all coastal wetland investigated. This study indicated that coastal wetland could still emit relatively high amount of methane even under high water salinity condiations, and plant activity played an important role in methane flux, and this role was highly species-specific.

  2. Floristic Quality Index of Restored Wetlands in Coastal Louisiana

    Science.gov (United States)

    2017-08-01

    ER D C/ EL T R- 17 -1 5 Ecosystem Management and Restoration Research Program Floristic Quality Index of Restored Wetlands in Coastal...of Wisconsin Lake Plant Communities with Example Applications. Lake and Reservoir Management 15(2): 133-141. Rocchio, J. 2007. Floristic Quality ... quality in Ohio wetlands. Science of the Total Environment 551: (556-562). Steyer, G. D., and R. E. Stewart, Jr. 1992. Monitoring Program for Coastal

  3. The landscape pattern characteristics of coastal wetlands in Jiaozhou Bay under the impact of human activities.

    Science.gov (United States)

    Gu, Dongqi; Zhang, Yuanzhi; Fu, Jun; Zhang, Xuliang

    2007-01-01

    In this study, we interpreted coastal wetland types from an ASTER satellite image in 2002, and then compared the results with the land-use status of coastal wetlands in 1952 to determine the wetland loss and degradation around Jiaozhou Bay. Seven types of wetland landscape were classified, namely: shallow open water, inter-tidal flats, estuarine water, brackish marshes, salt ponds, fishery ponds and ports. Several landscape pattern indices were analysed: the results indicate that the coastal wetlands have been seriously degraded. More and more natural wetlands have been transformed into artificial wetlands, which covered about 33.7% of the total wetlands in 2002. In addition, we used a defined model to assess the impacts of human activities on coastal wetlands. The results obtained show that the coastal wetlands of Jiaozhou Bay have suffered severe human disturbance. Effective coastal management and control is therefore needed to solve the issues of the coastal wetland loss and degradation existing in this area.

  4. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Mississippi: WETLANDS (Wetland Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing coastal wetlands classified according to the Environmental Sensitivity Index (ESI) classification system for...

  5. Functional roles of wetlands: a case study of the coastal wetlands of ...

    African Journals Online (AJOL)

    The Coastal Wetland of the study area is used extensively for a large number of activities. It is also threatened because of their vulnerability and attractiveness for development. These therefore prompted a study of the Wetlands for a period of 18 months (July 1997 – December 1998) to identify the functional roles that ...

  6. LAND COVER - CLASSIFICATION and Other Data from FIXED PLATFORM From Coastal Waters of Gulf of Mexico from 19880101 to 19891231 (NODC Accession 9100034)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Wetland Assessment Data was collected from Coastal waters of Gulf of Mexico by Louisiana State and the Louisiana Geological Service under MMS Cooperative Agreement...

  7. North American coastal carbon stocks and exchanges among the coupled ecosystems of tidal wetlands and estuaries

    Science.gov (United States)

    Windham-Myers, L.; Cai, W. J.

    2017-12-01

    The development of the 2nd State of the Carbon Cycle Report (SOCCR-2) has recognized a significant role of aquatic ecosystems, including coastal zones, in reconciling some of the gaps associated with the North American carbon (C) budget. Along with a large community of coauthors, we report major C stocks and fluxes for tidal wetlands and estuaries of Canada, Mexico and the United States. We find divergent patterns between these coupled ecosystems, with tidal wetlands largely serving as CO2 sinks (net autotrophic), and open-water estuaries largely serving as CO2 sources (net heterotrophic). We summarized measurements across 4 continental regions - East Coast, Gulf of Mexico, West Coast, and High Latitudes - to assess spatial variability and datagaps in our understanding of coastal C cycling. Subtracting estuarine outgassing of 10 ± 10 Tg C yr-1 from the tidal wetland uptake of 23 ± 10 Tg C yr-1 leaves a net uptake of the combined system of 13 ± 14 Tg C yr-1. High uncertainty for net atmospheric C exchange in this combined coastal system is further complicated by spatially and temporally dynamic boundaries, as well as terrestrial C sources. Tidal wetlands are among the most productive ecosystems on earth and are capable of continuously accumulating organic C in their sediments as a result of environmental conditions that inhibit organic matter decomposition. Estuaries have more interannual variability in C dynamics than those of tidal wetlands, reflecting the estuarine balance of exchanges with terrestrial watersheds, tidal wetlands, and the continental shelf. Whereas tidal, subtidal and estuarine maps are of limited accuracy at larger scales, North America likely represents less than 1/10 of global distributions of coastal wetland habitats. Coupled land-ocean C flux models are increasingly robust but lacking much of the data needed for parameterization and validation. Accurate boundary maps and synoptic monitoring data on air-water CO2 exchange may be developed

  8. Coastal wetlands, sea level, and the dimensions of geomorphic resilience

    Science.gov (United States)

    Phillips, Jonathan D.

    2018-03-01

    Geomorphic system resilience is often perceived as an intrinsic property of system structure and interactions but is also related to idiosyncratic place and history factors. The importance of geographical and historical circumstances makes it difficult to generate categorical statements about geomorphic resilience. However, network-based analyses of system structure can be used to determine the dynamical stability (= resilience) based on generally applicable relationships and to determine scenarios of stability or instability. These provide guidelines for assessing place and history factors to assess resilience. A model of coastal wetlands is analyzed, based on interactions among relative sea level, wetland surface elevation, hydroperiod, vegetation, and sedimentation. The system is generally (but not always) dynamically unstable and non-resilient. Because of gradients of environmental factors and patchy distributions of microtopography and vegetation, a coastal wetland landscape may have extensive local variations in stability/resilience and in the key relationships that trigger instabilities. This is illustrated by a case study where dynamically unstable fragmentation is found in two nearby coastal wetlands in North Carolina's Neuse River estuary-Otter Creek Mouth and Anderson Creek. Neither is keeping pace with relative sea level rise, and both show unstable state transitions within the wetland system; but locally stable relationships exist within the wetland systems.

  9. China's coastal wetlands: conservation history, implementation efforts, existing issues and strategies for future improvement.

    Science.gov (United States)

    Sun, Zhigao; Sun, Wenguang; Tong, Chuan; Zeng, Congsheng; Yu, Xiang; Mou, Xiaojie

    2015-06-01

    China has approximately 5.80×10(6)ha coastal wetlands by 2014, accounting for 10.82% of the total area of natural wetlands. Healthy coastal wetland ecosystems play an important role in guaranteeing the territory ecological security and the sustainable development of coastal zone in China. In this paper, the natural geography and the past and present status of China's coastal wetlands were introduced and the five stages (1950s-1970s, 1980s-1991, 1992-2002, 2003-2010 and 2011-present) of China's coastal wetlands conservation from the foundation of the People's Republic in 1949 to present were distinguished and reviewed. Over the past decades, China has made great efforts in coastal wetland conservation, as signified by the implementation of coastal wetland restoration projects, the construction of coastal wetland nature reserves, the practice of routine ecological monitoring and two national wetland surveys, the promulgation of local wetland conservation statutes and specific regulations, the coordination mechanism to enhance management capacity, the wide development of coastal wetland research and public participation, and the extensive communication to strengthen international cooperation. Nonetheless, six major issues recently emerged in China's coastal wetland conservation are evidently existed, including the increasing threats of pollution and human activities, the increasing adverse effects of threaten factors on ecosystem function, the increasing threats of coastal erosion and sea-level rising, the insufficient funding for coastal wetlands conservation, the imperfect legal and management system for coastal wetlands, and the insufficient education, research and international cooperation. Although the threats and pressures on coastal wetlands conservation are still apparent, the future of China's coastal wetlands looks promising since the Chinese government understands that the sustainable development in coastal zone requires new attitudes, sound policies and

  10. Trends and causes of historical wetland loss in coastal Louisiana

    Science.gov (United States)

    Bernier, Julie

    2013-01-01

    Wetland losses in the northern Gulf Coast region of the United States are so extensive that they represent critical concerns to government environmental agencies and natural resource managers. In Louisiana, almost 3,000 square kilometers (km2) of low-lying wetlands converted to open water between 1956 and 2004, and billions of dollars in State and Federal funding have been allocated for coastal restoration projects intended to compensate for some of those wetland losses. Recent research at the St. Petersburg Coastal and Marine Science Center (SPCMSC) focused on understanding the physical processes and human activities that contributed to historical wetland loss in coastal Louisiana and the spatial and temporal trends of that loss. The physical processes (land-surface subsidence and sediment erosion) responsible for historical wetland loss were quantified by comparing marsh-surface elevations, water depths, and vertical displacements of stratigraphic contacts at 10 study areas in the Mississippi River delta plain and 6 sites at Sabine National Wildlife Refuge (SNWR) in the western chenier plain. The timing and extent of land loss at the study areas was determined by comparing historical maps, aerial photographs, and satellite imagery; the temporal and spatial trends of those losses were compared with historical subsidence rates and hydrocarbon production trends.

  11. Carbon stocks of tropical coastal wetlands within the karstic landscape of the Mexican Caribbean.

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Adame

    Full Text Available Coastal wetlands can have exceptionally large carbon (C stocks and their protection and restoration would constitute an effective mitigation strategy to climate change. Inclusion of coastal ecosystems in mitigation strategies requires quantification of carbon stocks in order to calculate emissions or sequestration through time. In this study, we quantified the ecosystem C stocks of coastal wetlands of the Sian Ka'an Biosphere Reserve (SKBR in the Yucatan Peninsula, Mexico. We stratified the SKBR into different vegetation types (tall, medium and dwarf mangroves, and marshes, and examined relationships of environmental variables with C stocks. At nine sites within SKBR, we quantified ecosystem C stocks through measurement of above and belowground biomass, downed wood, and soil C. Additionally, we measured nitrogen (N and phosphorus (P from the soil and interstitial salinity. Tall mangroves had the highest C stocks (987±338 Mg ha(-1 followed by medium mangroves (623±41 Mg ha(-1, dwarf mangroves (381±52 Mg ha(-1 and marshes (177±73 Mg ha(-1. At all sites, soil C comprised the majority of the ecosystem C stocks (78-99%. Highest C stocks were measured in soils that were relatively low in salinity, high in P and low in N∶P, suggesting that P limits C sequestration and accumulation potential. In this karstic area, coastal wetlands, especially mangroves, are important C stocks. At the landscape scale, the coastal wetlands of Sian Ka'an covering ≈172,176 ha may store 43.2 to 58.0 million Mg of C.

  12. Fish resources of Lagos State coastal wetlands | Ayodele | African ...

    African Journals Online (AJOL)

    Fishing is the major occupation of the people found along the coastal wetland of Lagos State. Fishing is carried out all the year round. This study examines the fishing Activities, Gear composition and fishing methods in order to obtain the fish species and harvest composition of the study area. This paper is based on the ...

  13. Coastal Wetlands Protection Act: Case of Apalachicola-Chattahoochee-Flint (ACF) River

    OpenAIRE

    Latif Gürkan KAYA

    2007-01-01

    Coastal wetlands, being important components of estuarine and coastal systems, stand for all publicly owned lands subject to the ebb and flow of the tide. They are below the watermark of ordinary high tide. The coastal wetlands contain a vital natural resource system. The coastal wetlands resource system, unless impossible, to reconstruct or rehabilitate once adversely affected by human. In the USA, the Apalachicola-Chattahoochee-Flint (ACF) river states (i.e. Georgia, Alabama and Florida) ha...

  14. Radar geomorphology of coastal and wetland environments

    Science.gov (United States)

    Lewis, A. J.; Macdonald, H. C.

    1973-01-01

    Details regarding the collection of radar imagery over the past ten years are considered together with the geomorphic, geologic, and hydrologic data which have been extracted from radar imagery. Recent investigations were conducted of the Louisiana swamp marsh and the Oregon coast. It was found that radar imagery is a useful tool to the scientist involved in wetland research.

  15. Balancing Methane Emissions and Carbon Sequestration in Tropical/Subtropical Coastal Wetlands: A Review

    Science.gov (United States)

    Mitsch, W. J.; Schafer, K. V.; Cabezas, A.; Bernal, B.

    2016-02-01

    Wetlands are estimated to emit about 20 to 25 percent of current global CH4 emissions, or about 120 to 180 Tg-CH4 yr-1. Thus, in climate change discussions concerning wetlands, these "natural emissions" often receive the most attention, often overshadowing the more important ecosystem services that wetlands provide, including carbon sequestration. While methane emissions from coastal wetlands have generally been described as small due to competing biogeochemical cycles, disturbance of coastal wetlands, e.g., the introduction of excessive freshwater fluxes or substrate disturbance, can lead to much higher methane emission rates. Carbon sequestration is a more positive carbon story about wetlands and coastal wetlands in particular. The rates of carbon sequestration in tropical/subtropical coastal wetlands, mainly mangroves, are in the range of 100 to 200 g-C m-2 yr-1, two to ten times higher rates than in the more frequently studied northern peatlands. This function of coastal wetlands has significant international support now for mangrove conservation and it is referred to in the literature and popular press as blue carbon. This presentation will summarize what we know about methane emissions and carbon sequestration in tropical/subtropical coastal wetlands, how these rates compare with those in non-tropical and/or inland wetlands, and a demonstration of two or three models that compare methane fluxes with carbon dioxide sequestration to determine if wetlands are net sinks of radiative forcing. The presentation will also present a global model of carbon with an emphasis on wetlands.

  16. Wetlands as principal zones of methylmercury production in southern Louisiana and the Gulf of Mexico region

    Energy Technology Data Exchange (ETDEWEB)

    Hall, B.D. [Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, WI 53706 (United States); Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK, S4S 0A2 (Canada)], E-mail: britt.hall@uregina.ca; Aiken, G.R. [United States Geological Survey, 3215 Marine Street, Boulder, CO 80303 (United States); Krabbenhoft, D.P. [United States Geological Survey, 8505 Research Way, Middleton, WI 53562 (United States); Marvin-DiPasquale, M. [United States Geological Survey, 345 Middlefield Road, Menlo Park, CA 94025 (United States); Swarzenski, C.M. [United States Geological Survey, Suite 120, 3535 S. Sherwood Forest Blvd., Baton Rouge, LA 70816 (United States)

    2008-07-15

    It is widely recognized that wetlands, especially those rich in organic matter and receiving appreciable atmospheric mercury (Hg) inputs, are important sites of methylmercury (MeHg) production. Extensive wetlands in the southeastern United States have many ecosystem attributes ideal for promoting high MeHg production rates; however, relatively few mercury cycling studies have been conducted in these environments. We conducted a landscape scale study examining Hg cycling in coastal Louisiana (USA) including four field trips conducted between August 2003 and May 2005. Sites were chosen to represent different ecosystem types, including: a large shallow eutrophic estuarine lake (Lake Pontchartrain), three rivers draining into the lake, a cypress-tupelo dominated freshwater swamp, and six emergent marshes ranging from a freshwater marsh dominated by Panicum hemitomon to a Spartina alterniflora dominated salt marsh close to the Gulf of Mexico. We measured MeHg and total Hg (THg) concentrations, and ancillary chemical characteristics, in whole and filtered surface water, and filtered porewater. Overall, MeHg concentrations were greatest in surface water of freshwater wetlands and lowest in the profundal (non-vegetated) regions of the lake and river mainstems. Concentrations of THg and MeHg in filtered surface water were positively correlated with the highly reactive, aromatic (hydrophobic organic acid) fraction of dissolved organic carbon (DOC). These results suggest that DOC plays an important role in promoting the mobility, transport and bioavailability of inorganic Hg in these environments. Further, elevated porewater concentrations in marine and brackish wetlands suggest coastal wetlands along the Gulf Coast are key sites for MeHg production and may be a principal source of MeHg to foodwebs in the Gulf of Mexico. Examining the relationships among MeHg, THg, and DOC across these multiple landscape types is a first step in evaluating possible links between key zones for

  17. Wetlands as principal zones of methylmercury production in southern Louisiana and the Gulf of Mexico region

    International Nuclear Information System (INIS)

    Hall, B.D.; Aiken, G.R.; Krabbenhoft, D.P.; Marvin-DiPasquale, M.; Swarzenski, C.M.

    2008-01-01

    It is widely recognized that wetlands, especially those rich in organic matter and receiving appreciable atmospheric mercury (Hg) inputs, are important sites of methylmercury (MeHg) production. Extensive wetlands in the southeastern United States have many ecosystem attributes ideal for promoting high MeHg production rates; however, relatively few mercury cycling studies have been conducted in these environments. We conducted a landscape scale study examining Hg cycling in coastal Louisiana (USA) including four field trips conducted between August 2003 and May 2005. Sites were chosen to represent different ecosystem types, including: a large shallow eutrophic estuarine lake (Lake Pontchartrain), three rivers draining into the lake, a cypress-tupelo dominated freshwater swamp, and six emergent marshes ranging from a freshwater marsh dominated by Panicum hemitomon to a Spartina alterniflora dominated salt marsh close to the Gulf of Mexico. We measured MeHg and total Hg (THg) concentrations, and ancillary chemical characteristics, in whole and filtered surface water, and filtered porewater. Overall, MeHg concentrations were greatest in surface water of freshwater wetlands and lowest in the profundal (non-vegetated) regions of the lake and river mainstems. Concentrations of THg and MeHg in filtered surface water were positively correlated with the highly reactive, aromatic (hydrophobic organic acid) fraction of dissolved organic carbon (DOC). These results suggest that DOC plays an important role in promoting the mobility, transport and bioavailability of inorganic Hg in these environments. Further, elevated porewater concentrations in marine and brackish wetlands suggest coastal wetlands along the Gulf Coast are key sites for MeHg production and may be a principal source of MeHg to foodwebs in the Gulf of Mexico. Examining the relationships among MeHg, THg, and DOC across these multiple landscape types is a first step in evaluating possible links between key zones for

  18. Analysis of fish movements between Great Lakes coastal wetlands and near shore habitat via otolith microchemistry

    Science.gov (United States)

    Great Lakes coastal wetlands are unique habitats with physical connections with near shore environments. This facilitates the exchange of energy between habitats in a principle known as habitat coupling. Coupling can be facilitated by movements of consumers; however, wetland us...

  19. REMOTE DETENTION OF INVASIVE AND OPPORTUNISTIC PLANT SPECIES IN GREAT LAKES COASTAL WETLANDS

    Science.gov (United States)

    Invasive and opportunistic plant species have been associated with wetland disturbance. Increases in the abundance of plant species such as common reed (Phragmites australis) in coastal Great Lakes wetlands are hypothesized to occur with shifts toward drier hydrologic regimes, fr...

  20. Direct impacts of outer continental shelf activities on wetland loss in the central Gulf of Mexico

    International Nuclear Information System (INIS)

    Baumann, R.H.; Turner, R.E.

    1990-01-01

    The direct impacts of outer continental shelf (OCS) development on recent wetland loss in the northern Gulf of Mexico were quantified using aerial imagery, field surveys, and literature review. The total direct impacts accounted for an estimated 25.6 percent of total net wetland loss within the Louisiana portion of the study area from 1955/56 to 1978. Of the total direct impacts of 73,905 ha, OCS-related activities accounted for 11,589-13,631 ha of the wetland loss during the same time interval. Although this is a substantial areal loss, it represents only 4.0-4.7 percent of the total Louisiana wetland loss from 1955/56 to 1978, and 15.7-18.4 percent of direct impacts. Direct impacts from OCS pipelines averages 2.49 ha/km, lower than published guidelines, and totaled 12,012 ha. Lowest impacts are for backfilled pipelines in the Chenier Plain of western Louisiana and for small young pipeline canals does not appear to be an important factor for total new wetland loss in the coastal zone because few pipelines are open to navigation and, for the examples found, the impact width was not significantly different than for open pipelines closed to navigation. Navigation channels account for a minimum of 16,902 ha of habitat change. Direct impacts per unit length of navigation channel average 20 times greater than pipelines

  1. Effects of Land Use Changes on the Ecosystem Service Values of Coastal Wetlands

    Science.gov (United States)

    Camacho-Valdez, Vera; Ruiz-Luna, Arturo; Ghermandi, Andrea; Berlanga-Robles, César A.; Nunes, Paulo A. L. D.

    2014-10-01

    Changes in the coastal landscape of Southern Sinaloa (Mexico), between 2000 and 2010, were analyzed to relate spatial variations in wetlands extent with the provision and economic value of the ecosystem services (ES). Remote sensing techniques applied to Landsat TM imagery were used to evaluate land use/land cover changes while the value transfer method was used to assess the value of ES by land cover category. Five wetland types and other four land covers were found as representative of the coastal landscape. Findings reveal a 14 % decrease in the saltmarsh/forested mangrove area and a 12 % increase in the area of shrimp pond aquaculture (artificial wetland) during the study period. ES valuation shows that the total value flow increased by 9 % from 215 to 233 million (2007 USD) during the 10-year period. This increase is explained as result of the high value worldwide assigned to saltmarsh. We recognize limitations in the transfer-based approach in quantifying and mapping ES values in the region, but this method provides with value estimates spatially defined, and also provides some guidance in the preliminary screening of policies and projected development in the context of data-scarce regions.

  2. Monitoring coastal wetlands in a highly dynamic tropical environment

    International Nuclear Information System (INIS)

    Saynor, M.J.; Finlayson, C.M.; Spiers, A.; Eliot, I.

    2001-01-01

    The Alligator Rivers Region in the wet-dry tropics of northern Australia has been selected by government and collaborating agencies as a key study area for the monitoring of natural and human-induced coastal change. The Region contains the floodplain wetlands of Kakadu National Park which have been recognised internationally for their natural and cultural heritage value. A coastal monitoring program for assessing and monitoring environmental change in the Alligator Rivers Region has been established at the Environmental Research Institute of the Supervising Scientist. This program has developed a regional capacity to measure and assess change on the wetlands, floodplains and coastline within the region. Field assessment and monitoring procedures have been developed for the program. The assessment procedures require use of georeferencing and data handling techniques to facilitate comparison and relational overlay of a wide variety of information. Monitoring includes regular survey of biophysical and cultural processes on the floodplains; such as the extension of tidal creeks and mangroves, shoreline movement, dieback in Melaleuca wetlands, and weed invasion of freshwater wetlands. A differential Global Positioning System is used to accurately georeference spatial data and a Geographic Information System is then used to store and assess information. The assessment and monitoring procedures can be applied to the wet-dry tropics in general. These studies are all particularly pertinent with the possibility of greenhouse gases causing global warming and potential sea-level rise, a major possible threat to the valued wetlands of Kakadu National Park, and across the wet-dry tropics in general

  3. Changes of hydrological environment and their influences on coastal wetlands in the southern Laizhou Bay, China.

    Science.gov (United States)

    Zhang, Xuliang; Zhang, Yuanzhi; Sun, Hongxia; Xia, Dongxing

    2006-08-01

    The structure and function of the coastal wetland ecosystem in the southern Laizhou Bay have been changed greatly and influenced by regional hydrological changes. The coastal wetlands have degraded significantly during the latest 30 years due to successive drought, decreasing of runoff, pollution, underground saline water intrusion, and aggravating marine disasters such as storm tides and sea level rising. Most archaic lakes have vanished, while artificial wetlands have been extending since natural coastal wetlands replaced by salt areas and ponds of shrimps and crabs. The pollution of sediments in inter-tidal wetlands and the pollution of water quality in sub-tidal wetlands are getting worse and therefore "red tides" happen more often than before. The biodiversity in the study area has been decreased. Further studies are still needed to protect the degraded coastal wetlands in the area.

  4. Thresholds of sea-level rise rate and sea-level acceleration rate in a vulnerable coastal wetland

    Science.gov (United States)

    Wu, W.; Biber, P.; Bethel, M.

    2017-12-01

    Feedback among inundation, sediment trapping, and vegetation productivity help maintain coastal wetlands facing sea-level rise (SLR). However, when the SLR rate exceeds a threshold, coastal wetlands can collapse. Understanding the threshold help address the key challenge in ecology - nonlinear response of ecosystems to environmental change, and promote communication between ecologists and policy makers. We studied the threshold of SLR rate and developed a new threshold of SLR acceleration rate on sustainability of coastal wetlands as SLR is likely to accelerate due to the enhanced anthropogenic forces. We developed a mechanistic model to simulate wetland change and derived the SLR thresholds for Grand Bay, MS, a micro-tidal estuary with limited upland freshwater and sediment input in the northern Gulf of Mexico. The new SLR acceleration rate threshold complements the threshold of SLR rate and can help explain the temporal lag before the rapid decline of wetland area becomes evident after the SLR rate threshold is exceeded. Deriving these two thresholds depends on the temporal scale, the interaction of SLR with other environmental factors, and landscape metrics, which have not been fully accounted for before this study. The derived SLR rate thresholds range from 7.3 mm/yr to 11.9 mm/yr. The thresholds of SLR acceleration rate are 3.02×10-4 m/yr2 and 9.62×10-5 m/yr2 for 2050 and 2100 respectively. Based on the thresholds developed, predicted SLR that will adversely impact the coastal wetlands in Grand Bay by 2100 will fall within the likely range of SLR under a high warming scenario (RCP8.5), and beyond the very likely range under a low warming scenario (RCP2.6 or 3), highlighting the need to avoid the high warming scenario in the future if these marshes are to be preserved.

  5. Innovative approach for restoring coastal wetlands using treated drill cuttings

    International Nuclear Information System (INIS)

    Veil, J. A.; Hocking, E. K.

    1999-01-01

    The leading environmental problem facing coastal Louisiana regions is the loss of wetlands. Oil and gas exploration and production activities have contributed to wetland damage through erosion at numerous sites where canals have been cut through the marsh to access drilling sites. An independent oil and gas producer, working with Southeastern Louisiana University and two oil field service companies, developed a process to stabilize drill cuttings so that they could be used as a substrate to grow wetlands vegetation. The U.S. Department of Energy (DOE) funded a project under which the process would be validated through laboratory studies and field demonstrations. The laboratory studies demonstrated that treated drill cuttings support the growth of wetlands vegetation. However, neither the Army Corps of Engineers (COE) nor the U.S. Environmental Protection Agency (EPA) would grant regulatory approval for afield trial of the process. Argonne National Laboratory was asked to join the project team to try to find alternative mechanisms for gaining regulatory approval. Argonne worked with EPA's Office of Reinvention and learned that EPA's Project XL would be the only regulatory program under which the proposed field trial could be done. One of the main criteria for an acceptable Project XL proposal is to have a formal project sponsor assume the responsibility and liability for the project. Because the proposed project involved access to private land areas, the team felt that an oil and gas company with coastal Louisiana land holdings would need to serve as sponsor. Despite extensive communication with oil and gas companies and industry associations, the project team was unable to find any organization willing to serve as sponsor. In September 1999, the Project XL proposal was withdrawn and the project was canceled

  6. Wildlife resources of coastal wetlands of Lagos state | Jenyo-Oni ...

    African Journals Online (AJOL)

    Almost 35% of all rare and endangered animal species are either located in wetland areas or are dependent on them. Coastal wetlands are extremely important to coastal states such as the study area and are extensively exploited. This study gives an inventory of the wildlife resources of the study area and its utilization.

  7. Fringe benefit: Value of restoring coastal wetlands for Great Lakes fisheries

    Science.gov (United States)

    Fishery support is recognized as a valuable ecosystem service provided by Great Lakes coastal wetlands, but it is challenging to quantify because multiple species and habitats are involved. Recent studies indicate that coastal wetland area is proportional to fishery harvest among...

  8. Progress in understanding the importance of coastal wetland nursery habitat to Great Lakes fisheries support

    Science.gov (United States)

    Great Lakes coastal wetlands provide important habitat for Great Lakes fishes of all life stages. A literature review of ichthyoplankton surveys conducted in Great Lakes coastal wetlands found at least 82 species reported to be captured during the larval stage. Twenty of those sp...

  9. Coastal Wetlands Protection Act: Case of Apalachicola-Chattahoochee-Flint (ACF River

    Directory of Open Access Journals (Sweden)

    Latif Gürkan KAYA

    2007-01-01

    Full Text Available Coastal wetlands, being important components of estuarine and coastal systems, stand for all publicly owned lands subject to the ebb and flow of the tide. They are below the watermark of ordinary high tide. The coastal wetlands contain a vital natural resource system. The coastal wetlands resource system, unless impossible, to reconstruct or rehabilitate once adversely affected by human. In the USA, the Apalachicola-Chattahoochee-Flint (ACF river states (i.e. Georgia, Alabama and Florida have variation in the structure and the function of their wetland program affecting the ACF river basins' wetlands. Although some states have no special wetlands program, they have permits and water quality certification for these areas. Some state programs affect state agencies while local government implements other programs.

  10. Nitrogen source tracking with δ15N content of coastal wetland plants in Hawaii

    Science.gov (United States)

    Gregory L. Bruland; Richard A.. Mackenzie

    2010-01-01

    Inter- and intra-site comparisons of the nitrogen (N) stable isotope composition of wetland plant species have been used to identify sources of N in coastal areas. In this study, we compared δ15N values from different herbaceous wetland plants across 34 different coastal wetlands from the five main Hawaiian Islands and investigated relationships of δ15N with...

  11. A comparison of the vegetation and soils of natural, restored, and created coastal lowland wetlands in Hawai‘i

    Science.gov (United States)

    Meris Bantilan-Smith; Gregory L. Bruland; Richard A. MacKenzie; Adonia R. Henry; Christina R. Ryder

    2009-01-01

    The loss of coastal wetlands throughout the Hawaiian Islands has increased the numbers of created (CW) and restored (RW) wetlands. An assessment of these wetlands has yet to occur, and it has not been determined whether CWs and RWs provide the same functions as natural wetlands (NWs). To address these concerns, vegetation and soil characteristics of 35 wetlands were...

  12. Predicting Disturbance-driven Impacts on Ecosystem Services in Coastal Wetlands

    Science.gov (United States)

    Rajan, S.; Crawford, P.; Kleinhuizen, A.; Mortazavi, B.; Sobecky, P.

    2017-12-01

    Natural and human-induced disturbances pose significant threats to the health and long-term productivity of Alabama coastal wetlands. As wetlands are a vital state resource, decisions on management, restoration, and remediation require actionable data if socio-economic demands are to be balanced with efforts to sustain these habitats. In 2010, the BP oil spill was a large and severe disturbance that threatened coastal Gulf ecosystem services. The largest marine oil spill to date served to highlight fundamental gaps in our knowledge of oil-induced disturbances and the resiliency and restoration of coastal Alabama wetland functions. To address these gaps, a year-long mesocosm study was conducted to investigate oil-induced effects on (i) plant-microbial interactions, (ii) microbial and plant biodiversity, and, (iii) the contributions of microbial genetic biodiversity to ecosystems services. In this study, Avicennia germinans (black mangrove), a C3 plant that grows from the tropics to warm temperate latitudes, were grown with or without mono- and polyculture mixtures of Spartina alterniflora, a C4 plant. At an interval of 3-months, oil was introduced as a pulse disturbance to achieve a concentration of 4000 ppm. Molecular-based analyses of microbial community biodiversity, genetic diversity, and functional metabolic genes were compared to controls (i.e., no oil disturbance). To assess the oil-induced effects on the nitrogen (N) cycle, measurements of denitrification and N fixation processes were conducted. Our results showed that community diversity and phylogenetic diversity significantly changed and that the oil disturbance contributed to the creation of niches for distinct microbial types. The abundance of N-fixing microbial types increased as the abundance of denitrifying microbial types decreased as a result of the oil disturbance. As denitrification is an ecosystem service that directly contributes to removing nitrate (NO3-) loading to coastal zones, impairment

  13. Biodiversity impacts from salinity increase in a coastal wetland.

    Science.gov (United States)

    Amores, Maria José; Verones, Francesca; Raptis, Catherine; Juraske, Ronnie; Pfister, Stephan; Stoessel, Franziska; Antón, Assumpció; Castells, Francesc; Hellweg, Stefanie

    2013-06-18

    A Life Cycle Impact Assessment method was developed to evaluate the environmental impact associated with salinity on biodiversity in a Spanish coastal wetland. The developed characterization factor consists of a fate and an effect factor and equals 3.16 × 10(-1) ± 1.84 × 10(-1) PAF · m(3) · yr · m(-3) (PAF: Potentially Affected Fraction of species) indicating a "potential loss of 0.32 m(3) ecosystem" for a water consumption rate of 1 m(3) · yr(-1). As a result of groundwater consumption with a rate of 1 m(3) · yr(-1), the PAF in the lost cubic meter of ecosystem equals 0.05, which has been proposed as the maximum tolerable effect to keep the ecosystem intact. The fate factor was calculated from seasonal water balances of the wetland Albufera de Adra. The effect factor was obtained from the fitted curve of the potentially affected fraction of native wetland species due to salinity and can be applied to other wetlands with similar species composition. In order to test the applicability of the characterization factor, an assessment of water consumption of greenhouse crops in the area was conducted as a case study. Results converted into ecosystem quality damage using the ReCiPe method were compared to other categories. While tomatoes are responsible for up to 30% of the impact of increased salinity due to water consumption on ecosystem quality in the studied area, melons have the largest impact per tonne produced.

  14. [Vulnerability assessment on the coastal wetlands in the Yangtze Estuary under sea-level rise].

    Science.gov (United States)

    Cui, Li-Fang; Wang, Ning; Ge, Zhen-Ming; Zhang, Li-Quan

    2014-02-01

    To study the response of coastal wetlands to climate change, assess the impacts of climate change on the coastal wetlands and formulate feasible and practical mitigation strategies are the important prerequisite for securing coastal ecosystems. In this paper, the possible impacts of sea level rise caused by climate change on the coastal wetlands in the Yangtze Estuary were analyzed by the Source-Pathway-Receptor-Consequence (SPRC) model and IPCC definition on the vulnerability. An indicator system for vulnerability assessment was established, in which sea-level rise rate, subsidence rate, habitat elevation, inundation threshold of habitat and sedimentation rate were selected as the key indicators. A quantitatively spatial assessment method based on the GIS platform was established by quantifying each indicator, calculating the vulnerability index and grading the vulnerability index for the assessment of coastal wetlands in the Yangtze Estuary under the scenarios of sea-level rise. The vulnerability assessments on the coastal wetlands in the Yangtze Estuary in 2030 and 2050 were performed under two sea-level rise scenarios (the present sea-level rise trend over recent 30 years and IPCC A1F1 scenario). The results showed that with the projection in 2030 under the present trend of sea-level rise (0.26 cm x a(-1)), 6.6% and 0.1% of the coastal wetlands were in the low and moderate vulnerabilities, respectively; and in 2050, 9.8% and 0.2% of the coastal wetlands were in low and moderate vulnerabilities, respectively. With the projection in 2030 under the A1F1 scenario (0.59 cm x a(-1)), 9.0% and 0.1% of the coastal wetlands were in the low and moderate vulnerabilities, respectively; and in 2050, 9.5%, 1.0% and 0.3% of the coastal wetlands were in the low, moderate and high vulnerabilities, respectively.

  15. Analysing how plants in coastal wetlands respond to varying tidal regimes throughout their life cycles.

    Science.gov (United States)

    Xie, Tian; Cui, Baoshan; Li, Shanze

    2017-10-15

    Important to conserve plant species in coastal wetlands throughout their life cycle. All life stages in these habitats are exposed to varying tidal cycles. It is necessary to investigate all life stages as to how they respond to varying tidal regimes. We examine three wetlands containing populations of an endangered halophyte species, each subjected to different tidal regimes: (1). wetlands completely closed to tidal cycles; (2). wetlands directly exposed to tidal cycles (3). wetlands exposed to a partially closed tidal regime. Our results showed that the most threatened stage varied between wetlands subjected to these varying tidal regimes. We hypothesis that populations of this species have adapted to these different tidal regimes. Such information is useful in developing management options for coastal wetlands and modifying future barriers restricting tidal flushing. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Understanding the Hydrodynamics of a Coastal Wetland with an Integrated Distributed Model

    Science.gov (United States)

    Zhang, Y.; Li, W.; Sun, G.

    2017-12-01

    Coastal wetlands linking ocean and terrestrial landscape provide important ecosystem services including flood mitigation, fresh water supply, erosion control, carbon sequestration, and wildlife habitats. Wetland hydrology is the major driving force for wetland formation, structure, function, and ecosystem services. The dynamics of wetland hydrology and energy budget are strongly affected by frequent inundation and drying of wetland soil and vegetation due to tide, sea level rise (SLR) and climatic variability (change). However, the quantitative representation of how the energy budget and groundwater variation of coastal wetlands respond to frequent water level fluctuation is limited, especially at regional scales. This study developed a physically based distributed wetland hydrological model by integrating coastal processes and considering the inundation influence on energy budget and ET. Analysis using in situ measurements and satellite data for a coastal wetland in North Carolina confirm that the model sufficiently captures the wetland hydrologic behaviors. The validated model was then applied to examine the wetland hydrodynamics under a 30-year historical climate forcing (1985-2014) for the wetland region. The simulation reveals that 43% of the study area has inundation events, 63% of which has a frequency higher than 50% each year. The canopy evaporation and transpiration decline dramatically when the inundation level exceeds the canopy height. Additionally, inundation causes about 10% increase of the net shortwave radiation. This study also demonstrates that the critical wetland zones highly influenced by the coastal processes spans 300-800 m from the coastline. The model developed in the study offers a new tool for understanding the complex wetland hydrodynamics in response to natural and human-induced disturbances at landscape to regional scales.

  17. Comprehensive Sediment Management to Improve Wetland Sustainability in Coastal Louisiana

    Science.gov (United States)

    Khalil, S.; Freeman, A. M.; Raynie, R.

    2016-02-01

    Human intervention has impaired the Mississippi River's ability to deliver sediment to its deltaic wetlands, and as a consequence acute land loss in coastal Louisiana has resulted in an unprecedented ecocatastrophe. Since the 1930s, Louisiana has lost approximately 5,000 square kilometers of coastal land, and is continuing to lose land at the rate of approximately 43 square kilometers/year. This extreme rate of land loss threatens a range of key national assets and important communities. Coastal communities across the world as well as in Louisiana have realized the importance of sediment for the continuation of their very existence in these productive but vulnerable regions. Ecological restoration can only be undertaken on a stable coastline, for which sedimentological restoration is needed. A large-scale effort to restore coastal Louisiana is underway, guided by Louisiana's Comprehensive Master Plan for a Sustainable Coast. This 50-year, $50-billion plan prescribes 109 protection and restoration projects to reduce land loss, maintain and restore coastal environments and sustain communities. Nowhere else has a restoration and protection program of this scale been developed or implemented, and critical to its success is the optimized usage of limited fluvial and offshore sediment resources, and a keen understanding of the complex interactions of various geological/geophysical processes in ecosystem restoration. A comprehensive sediment management plan has been developed to identify and delineate potential sediment sources for restoration, and to provide a framework for managing sediment resources wisely, cost effectively, and in a systematic manner. The Louisiana Sediment Management Plan provides regional strategies for improved comprehensive management of Louisiana's limited sediment resources. Adaptive management via a robust system-wide monitoring plays an important role along with a regional approach for the efficient management of sediment resources.

  18. Seasonality and flux estimates of dissolved organic carbon in tidal wetlands and estuaries in the U.S. Mid- Atlantic Bight and Gulf of Mexico from ocean color

    Science.gov (United States)

    Cao, F.; Tzortziou, M.; Hu, C.; Najjar, R.

    2016-02-01

    Tidal wetlands and estuaries are dynamic features of coastal ocean and play critical roles in the global carbon cycle. Exchanges of dissolved organic carbon (DOC) between tidal wetlands and adjacent estuaries have important implications for carbon sequestration in tidal wetlands as well as biogeochemical cycling of wetlands derived material in the coastal zones. Recent studies demonstrated that the absorption coefficients of chromophoric dissolved organic matter at λ= 275 and 295 nm, which can be derived from satellite ocean color observations, can be used to accurately retrieve dissolved organic carbon (DOC) in some coastal waters. Based on a synthesis of existing field observations collected covering wide spatial and temporal variability in the Mid-Atlantic Bight and the Gulf of Mexico, here we developed and validated new empirical models to estimate coastal DOC from remotely sensed bio-optical properties of the surface water. We focused on the interfaces between tidal wetland-estuary and estuary-shelf water domains. The DOC algorithms were applied to SeaWiFs and MODIS observations to generate long-term climatological DOC distributions from 1998 to 2014. Empirical orthogonal function analysis revealed strong seasonality and spatial gradients in the satellite retrieved DOC in the tidal wetlands and estuaries. Combined with field observations and biogeochemical models, satellite retrievals can be used to scale up carbon fluxes from individual marshes and sub-estuaries to the whole estuarine system, and improve understanding of biogeochemical exchanges between terrestrial and aquatic ecosystems.

  19. Thresholds of sea-level rise rate and sea-level rise acceleration rate in a vulnerable coastal wetland.

    Science.gov (United States)

    Wu, Wei; Biber, Patrick; Bethel, Matthew

    2017-12-01

    Feedbacks among inundation, sediment trapping, and vegetation productivity help maintain coastal wetlands facing sea-level rise (SLR). However, when the SLR rate exceeds a threshold, coastal wetlands can collapse. Understanding the threshold helps address key challenges in ecology-nonlinear response of ecosystems to environmental change, promotes communication between ecologists and resource managers, and facilitates decision-making in climate change policies. We studied the threshold of SLR rate and developed a new threshold of SLR acceleration rate on sustainability of coastal wetlands as SLR is likely to accelerate due to enhanced anthropogenic forces. Deriving these two thresholds depends on the temporal scale, the interaction of SLR with other environmental factors, and landscape metrics, which have not been fully accounted for before this study. We chose a representative marine-dominated estuary in the northern Gulf of Mexico, Grand Bay in Mississippi, to test the concept of SLR thresholds. We developed a mechanistic model to simulate wetland change and then derived the SLR thresholds for Grand Bay. The model results show that the threshold of SLR rate in Grand Bay is 11.9 mm/year for 2050, and it drops to 8.4 mm/year for 2100 using total wetland area as a landscape metric. The corresponding SLR acceleration rate thresholds are 3.02 × 10 -4  m/year 2 and 9.62 × 10 -5  m/year 2 for 2050 and 2100, respectively. The newly developed SLR acceleration rate threshold can help quantify the temporal lag before the rapid decline in wetland area becomes evident after the SLR rate threshold is exceeded, and cumulative SLR a wetland can adapt to under the SLR acceleration scenarios. Based on the thresholds, SLR that will adversely impact the coastal wetlands in Grand Bay by 2100 will fall within the likely range of SLR under a high warming scenario (RCP8.5), highlighting the need to avoid RCP8.5 to preserve these marshes.

  20. Assessment on vulnerability of coastal wetlands to sea level rise in the Yangtze Estuary, China

    Science.gov (United States)

    Cui, L.; Ge, Z.; Zhang, L.

    2013-12-01

    The Yangtze Delta in China is vital economic hubs in terms of settlement, industry, agriculture, trade and tourism as well as of great environmental significance. In recent decades, the prospect of climate change, in particular sea level rise and its effects on low lying coastal areas have generated worldwide attention to coastal ecosystems. Coastal wetlands, as important parts of coastal ecosystem, are particularly sensitive to sea level rise. To study the responses of coastal wetlands to climate change, assess the impacts of climate change on coastal wetlands and formulate feasible and practical mitigation strategies are the important prerequisites for securing the coastal zone ecosystems. In this study, taking the coastal wetlands in the Yangtze Estuary as a case study, the potential impacts of sea-level rise to coastal wetlands habitat were analyzed by the Source-Pathway-Receptor-Consequence (SPRC) model. The key indicators, such as the sea-level rise rate, subsidence rate, elevation, daily inundation duration of habitat and sedimentation rate, were selected to build a vulnerability assessment system according to the IPCC definition of vulnerability, i.e. the aspects of exposure, sensitivity and adaptation. A quantitatively spatial assessment method on the GIS platform was established by quantifying each indicator, calculating the vulnerability index and grading the vulnerability. The vulnerability assessment on the coastal wetlands in the Yangtze Estuary under the sea level rise rate of the present trend and IPCC A1F1 scenario were performed for three sets of projections of short-term (2030s), mid-term (2050s) and long-term (2100s). The results showed that at the present trend of sea level rise rate of 0.26 cm/a, 92.3 % of the coastal wetlands in the Yangtze Estuary was in the EVI score of 0 in 2030s, i.e. the impact of sea level rise on habitats/species of coastal wetlands was negligible. While 7.4 % and 0.3 % of the coastal wetlands were in the EVI score of

  1. A meta-analysis of coastal wetland ecosystem services in Liaoning Province, China

    Science.gov (United States)

    Sun, Baodi; Cui, Lijuan; Li, Wei; Kang, Xiaoming; Pan, Xu; Lei, Yinru

    2018-01-01

    Wetlands are impacted by economic and political initiatives, and their ecosystem services are attracting increasing public attention. It is crucial that management decisions for wetland ecosystem services quantify the economic value of the ecosystem services. In this paper, we aimed to estimate a monetary value for coastal wetland ecosystem services in Liaoning Province, China. We selected 433 observations from 85 previous coastal wetland economic evaluations (mostly in China) including detailed spatial and economic characteristics in each wetland, then used a meta-analysis scale transfer method to calculate the total value of coastal wetland ecosystem services in Liaoning Province. Our results demonstrated that, on average, the ecosystem services provided by seven different coastal wetland types were worth US40,648 per ha per year, and the total value was 28,990,439,041 in 2013. Shallow marine waters accounted for the largest proportion (83.97%). Variables with a significant positive effect on the ecosystem service values included GDP per capita, population density, distance from the wetland to the city center and the year of evaluation, while wetland size and latitude had negative relationships.

  2. Sources of atmospheric methane from coastal marine wetlands

    International Nuclear Information System (INIS)

    Harriss, R.C.; Sebacher, D.I.; Bartlett, K.B.; Bartlett, D.S.

    1982-01-01

    Biological methanogenesis in wetlands is believed to be one of the major sources of global tropospheric methane. The present paper reports measurements of methane distribution in the soils, sediments, water and vegetation of coastal marine wetlands. Measurements, carried out in the salt marshes Bay Tree Creek in Virginia and Panacea in northwest Florida, reveal methane concentrations in soils and sediments to vary with depth below the surface and with soil temperature. The fluxes of methane from marsh soils to the atmosphere at the soil-air interface are estimated to range from -0.00067 g CH 4 /sq m per day (methane sink) to 0.024 g CH 4 /sq m per day, with an average value of 0.0066 g CH 4 /sq m per day. Data also demonstrate the important role of tidal waters percolating through marsh soils in removing methane from the soils and releasing it to the atmosphere. The information obtained, together with previous studies, provides a framework for the design of a program based on in situ and remote sensing measurements to study the global methane cycle

  3. Wetland Responses to Sea Level Rise in the Northern Gulf of Mexico

    Science.gov (United States)

    Alizad, K.; Bilskie, M. V.; Hagen, S. C.; Medeiros, S. C.; Morris, J. T.

    2016-12-01

    Coastal regions are vulnerable to flood risk due to climate change, sea level rise, and wetland losses. The Northern Gulf of Mexico (NGOM) is a region in which extreme events are projected to be more intense under climate change and sea level rise scenarios [Wang et al., 2013; Bilskie et al., 2014]. Considering increased frequency and intensity of coastal flooding, wetlands are valuable natural resources that protect shorelines by dissipating waves and storm surges [Costanza et al., 2008]. Therefore, it is critical to investigate the response of salt marsh systems in different estuaries to sea level rise in the NGOM and their effects on storm surges to inform coastal managers to choose effective restoration plans. This research applies the coupled Hydro-MEM model [Alizad et al., 2016] to study three different estuarine systems in the NGOM. The model incorporates both sea level rise rate and feedbacks between physics and biology by coupling a hydrodynamic (ADCIRC) and salt marsh (MEM) model. The results of the model provide tidal hydrodynamics and biomass density change under four sea level rise projections during a 100-year period. The results are used to investigate marsh migration path in the estuarine systems. In addition, this study shows how marsh migration and biomass density change can impact storm surge modeling. The results imply the broader impacts of sea level rise on the estuarine systems in the NGOM. ReferencesAlizad, K., S. C. Hagen, J. T. Morris, P. Bacopoulos, M. V. Bilskie, J. Weishampel, and S. C. Medeiros (2016), A coupled, two-dimensional hydrodynamic-marsh model with biological feedback, Ecological Modeling, 327, 29-43. Bilskie, M. V., S. C. Hagen, S. C. Medeiros, and D. L. Passeri (2014), Dynamics of sea level rise and coastal flooding on a changing landscape, Geophysical Research Letters, 41(3), 927-934. Costanza, R., O. Pérez-Maqueo, M. L. Martinez, P. Sutton, S. J. Anderson, and K. Mulder (2008), The Value of Coastal Wetlands for Hurricane

  4. Waterfowl community from a protected artificial wetland in Mexico State, Mexico

    Directory of Open Access Journals (Sweden)

    Arturo Hernández-Colina

    2017-11-01

    Full Text Available Wetlands are one of the most important ecosystems worldwide due to the great biologic diversity that they harbor and the re­sources and ecosystem services that they provide; however, their conservation is seriously threatened. Waterfowl are one of the most representative components of wetland biodiversity and the study of their communities is necessary to establish protection priorities appropriately. In this study, we describe the species richness and relative abundance of the waterfowl community of an artificial wetland in Mexico State which we visited from August 2010 to August 2011. We found 23 species, most of which belong to the Anatidae (ducks and Ardeidae (herons families and we recorded an accumulated abundance of 25,220 individuals. We performed an accumulation curve and we used Clench’s model which estimated 24 species; thus, we observed 95% of the predicted species. The arrival of migratory species contributed substantially to the increase of the species richness and the abundance of individuals, especially from October to March. We consider that the species richness and the abundance that we recorded, including observations of rare species, species reproducing, and species under a conservation category, are indicative of the great ecological value of this wetland despite its limited size. Therefore, it is relevant to assess ecological features of natural and artificial wetlands, including waterfowl communities, in order to improve the conservation actions in this region.

  5. Preliminary Evaluation of Critical Wave Energy Thresholds at Natural and Created Coastal Wetlands

    National Research Council Canada - National Science Library

    Shafer, Deborah

    2003-01-01

    This technical note presents an evaluation of the wave climate at eight natural and created coastal wetland sites in an effort to identify the existence of critical wave energy thresholds for long-term marsh stability...

  6. A global standard for monitoring coastal wetland vulnerability to accelerated sea-level rise

    Science.gov (United States)

    Webb, Edward L.; Friess, Daniel A.; Krauss, Ken W.; Cahoon, Donald R.; Guntenspergen, Glenn R.; Phelps, Jacob

    2013-01-01

    Sea-level rise threatens coastal salt-marshes and mangrove forests around the world, and a key determinant of coastal wetland vulnerability is whether its surface elevation can keep pace with rising sea level. Globally, a large data gap exists because wetland surface and shallow subsurface processes remain unaccounted for by traditional vulnerability assessments using tide gauges. Moreover, those processes vary substantially across wetlands, so modelling platforms require relevant local data. The low-cost, simple, high-precision rod surface-elevation table–marker horizon (RSET-MH) method fills this critical data gap, can be paired with spatial data sets and modelling and is financially and technically accessible to every country with coastal wetlands. Yet, RSET deployment has been limited to a few regions and purposes. A coordinated expansion of monitoring efforts, including development of regional networks that could support data sharing and collaboration, is crucial to adequately inform coastal climate change adaptation policy at several scales.

  7. Fertilizer legacies meet saltwater incursion: challenges and constraints for coastal plain wetland restoration

    Directory of Open Access Journals (Sweden)

    Marcelo Ardón

    2017-07-01

    Full Text Available Coastal wetland restoration is an important tool for climate change adaptation and excess nutrient runoff mitigation. However, the capacity of restored coastal wetlands to provide multiple ecosystem services is limited by stressors, such as excess nutrients from upstream agricultural fields, high nutrient legacies on-site, and rising salinities downstream. The effects of these stressors are exacerbated by an accelerating hydrologic cycle, expected to cause longer droughts punctuated by more severe storms. We used seven years of surface water and six years of soil solution water chemistry from a large (440 ha restored wetland to examine how fertilizer legacy, changes in hydrology, and drought-induced salinization affect dissolved nutrient and carbon concentrations. To better understand the recovery trajectory of the restored wetland, we also sampled an active agricultural field and two mature forested wetlands. Our results show that nitrogen (N and phosphorus (P concentrations in soil solution were 2–10 times higher in the restored wetland compared to two mature forested wetlands, presumably due to legacy fertilizer mobilized by reflooding. Despite elevated nutrient concentrations relative to reference wetlands, the restored wetland consistently attenuated N and P pulses delivered from an upstream farm. Even with continued loading, N and P concentrations in surface water throughout the restored wetland have decreased since the initial flooding. Our results suggest that high nutrient concentrations and export from wetlands restored on agricultural lands may be a severe but temporary problem. If field to wetland conversion is to become a more widespread method for ameliorating nutrient runoff and adapting coastal plain ecosystems to climate change, we should adopt new methods for minimizing the initial export phase of wetland restoration efforts.

  8. Integrated conceptual ecological model and habitat indices for the southwest Florida coastal wetlands

    Science.gov (United States)

    Wingard, G. Lynn; Lorenz, J. L.

    2014-01-01

    The coastal wetlands of southwest Florida that extend from Charlotte Harbor south to Cape Sable, contain more than 60,000 ha of mangroves and 22,177 ha of salt marsh. These coastal wetlands form a transition zone between the freshwater and marine environments of the South Florida Coastal Marine Ecosystem (SFCME). The coastal wetlands provide diverse ecosystem services that are valued by society and thus are important to the economy of the state. Species from throughout the region spend part of their life cycle in the coastal wetlands, including many marine and coastal-dependent species, making this zone critical to the ecosystem health of the Everglades and the SFCME. However, the coastal wetlands are increasingly vulnerable due to rising sea level, changes in storm intensity and frequency, land use, and water management practices. They are at the boundary of the region covered by the Comprehensive Everglades Restoration Plan (CERP), and thus are impacted by both CERP and marine resource management decisions. An integrated conceptual ecological model (ICEM) for the southwest coastal wetlands of Florida was developed that illustrates the linkages between drivers, pressures, ecological process, and ecosystem services. Five ecological indicators are presented: (1) mangrove community structure and spatial extent; (2) waterbirds; (3) prey-base fish and macroinvertebrates; (4) crocodilians; and (5) periphyton. Most of these indicators are already used in other areas of south Florida and the SFCME, and therefore will allow metrics from the coastal wetlands to be used in system-wide assessments that incorporate the entire Greater Everglades Ecosystem.

  9. Fish assemblages, connectivity, and habitat rehabilitation in a diked Great Lakes coastal wetland complex

    Science.gov (United States)

    Kowalski, Kurt P.; Wiley, Michael J.; Wilcox, Douglas A.

    2014-01-01

    Fish and plant assemblages in the highly modified Crane Creek coastal wetland complex of Lake Erie were sampled to characterize their spatial and seasonal patterns and to examine the implications of the hydrologic connection of diked wetland units to Lake Erie. Fyke netting captured 52 species and an abundance of fish in the Lake Erie–connected wetlands, but fewer than half of those species and much lower numbers and total masses of fish were captured in diked wetland units. Although all wetland units were immediately adjacent to Lake Erie, there were also pronounced differences in water quality and wetland vegetation between the hydrologically isolated and lake-connected wetlands. Large seasonal variations in fish assemblage composition and biomass were observed in connected wetland units but not in disconnected units. Reestablishment of hydrologic connectivity in diked wetland units would allow coastal Lake Erie fish to use these vegetated habitats seasonally, although connectivity does appear to pose some risks, such as the expansion of invasive plants and localized reductions in water quality. Periodic isolation and drawdown of the diked units could still be used to mimic intermediate levels of disturbance and manage invasive wetland vegetation.

  10. Analysis of Unmanned Aerial Vehicle (UAV) hyperspectral remote sensing monitoring key technology in coastal wetland

    Science.gov (United States)

    Ma, Yi; Zhang, Jie; Zhang, Jingyu

    2016-01-01

    The coastal wetland, a transitional zone between terrestrial ecosystems and marine ecosystems, is the type of great value to ecosystem services. For the recent 3 decades, area of the coastal wetland is decreasing and the ecological function is gradually degraded with the rapid development of economy, which restricts the sustainable development of economy and society in the coastal areas of China in turn. It is a major demand of the national reality to carry out the monitoring of coastal wetlands, to master the distribution and dynamic change. UAV, namely unmanned aerial vehicle, is a new platform for remote sensing. Compared with the traditional satellite and manned aerial remote sensing, it has the advantage of flexible implementation, no cloud cover, strong initiative and low cost. Image-spectrum merging is one character of high spectral remote sensing. At the same time of imaging, the spectral curve of each pixel is obtained, which is suitable for quantitative remote sensing, fine classification and target detection. Aimed at the frontier and hotspot of remote sensing monitoring technology, and faced the demand of the coastal wetland monitoring, this paper used UAV and the new remote sensor of high spectral imaging instrument to carry out the analysis of the key technologies of monitoring coastal wetlands by UAV on the basis of the current situation in overseas and domestic and the analysis of developing trend. According to the characteristic of airborne hyperspectral data on UAV, that is "three high and one many", the key technology research that should develop are promoted as follows: 1) the atmosphere correction of the UAV hyperspectral in coastal wetlands under the circumstance of complex underlying surface and variable geometry, 2) the best observation scale and scale transformation method of the UAV platform while monitoring the coastal wetland features, 3) the classification and detection method of typical features with high precision from multi scale

  11. Estimating coastal wetland gain and losses in Galveston County and Cameron County, Texas, USA.

    Science.gov (United States)

    Entwistle, Clare; Mora, Miguel A; Knight, Robert

    2018-01-01

    Coastal wetlands serve many important ecological services. One of these important ecological services is their use as storm buffers. Coastal wetlands provide habitat for migratory birds and aquatic species and can improve water quality. In the late 1990s, the US Fish and Wildlife Service (USFWS) published a study outlining the trends of coastal wetlands from the 1950s to early 1990s. In the present study, wetland gains and losses were calculated for Galveston County and Cameron County, Texas, USA, between 2001 and 2011. Maps from the National Land Cover Database were used to determine wetland areas for the years 2001, 2006, and 2011. ArcGIS was used to compare land cover between the study periods to determine overall wetland losses and gains. A statistical analysis was performed between wetland loss and population data to determine whether increased population density led to a higher loss of wetlands. Our analysis indicates that wetland loss is still occurring, however at a lower rate of loss (0.14%-0.18% annually) than the USFWS study predicted earlier (2.7%). In addition, the majority of wetland losses were due to conversion to upland areas. We found a positive correlation between increased population density and decreased wetland area; however, the trend was not significant. The present study shows how the majority of wetland loss in Galveston and Cameron counties is occurring as a result of increased upland areas. In addition, the present study shows that the use of online mapping systems can be used as a low-cost alternative to assess land changes when field tests are not feasible. Integr Environ Assess Manag 2018;14:120-129. © 2017 SETAC. © 2017 SETAC.

  12. Effects of tidal cycles on shorebird distribution and foraging behaviour in a coastal tropical wetland: Insights for carrying capacity assessment

    Science.gov (United States)

    Fonseca, Juanita; Basso, Enzo; Serrano, David; Navedo, Juan G.

    2017-11-01

    Wetland loss has driven negative effects on biodiversity by a reduction in potential available habitats, directly impacting wetland-dependent species such as migratory shorebirds. At coastal areas where tidal cycles can restrict food access, the degree to which density of foraging birds is mediated by conspecific abundance or by the available areas is crucial to understanding patterns of bird distribution and wetland carrying capacity. We used the bathymetry of two sectors modeled with two numerical matrices to determine the availability of intertidal foraging areas in relation to tidal level (spring and neap tides), and this information was used to estimate shorebird density and foraging activity throughout the low-tide cycle in a tropical coastal lagoon in northwestern Mexico. Relative to spring tides, an 80% reduction in available foraging areas occurred during neap tides. Overall shorebird abundance was significantly reduced during neap tide periods, with differences between species. Densities of shorebirds increased during neap tides, particularly in one sector, and remained similar throughout the low-tide period (i.e. 4 h) either during spring or neap tides. Time spent foraging was consistently lower during neap-tides relative to spring-tides, especially for Long-billed curlew (44% reduction), Willet (37% reduction) and Black-necked stilt (29% reduction). These decreases in foraging activity when available habitats became reduced can hamper the opportunities of migratory shorebirds to reach their daily energy requirements to survive during the non-breeding season. This study shows that when intertidal habitats are severely reduced an important fraction of shorebird populations would probably be forced to find alternative areas to forage or increase foraging time during the night. Serving an essential function as top-predators, these results can have important implications on carrying capacity assessment for shorebirds at coastal wetlands.

  13. Lake Superior Coastal Wetland Fish Assemblages and Habitat Conditions in Relation to Watershed Connectivity and Landcover

    Science.gov (United States)

    The role of the coastal margin and the watershed context in defining the ecology of even very large lakes is increasingly being recognized and examined. Coastal wetlands are both important contributors to the biodiversity and productivity of large lakes and important mediators o...

  14. Wetland Change Detection in Protected and Unprotected Indus Coastal and Inland Delta

    Science.gov (United States)

    Baig, M. H. Ali; Sultan, M.; Riaz Khan, M.; Zhang, L.; Kozlova, M.; Malik, N. Abbas; Wang, S.

    2017-09-01

    Worth of wetland sites lies in their ecological importance. They enhance ecosystem via provision of ecological services like improving water quality, groundwater infiltration, flood risk reduction and biodiversity regulation. Like other parts of the world Pakistan is also facing wetlands degradation. Ecological and economic significance of wetlands was recognized officially in 1971 as Pakistan became signatory of Ramsar wetland convention. Wetlands provide habitat to species of ecological and economic importance. Despite being recognized for international importance, Ramsar figures state that almost half of Pakistan's wetlands are at moderate or prominent level threat. Wetlands ecosystems are deteriorating at a rapid rate, if uncontrolled this trend may lead to substantial losses. Therefore, management of these resources demands regular monitoring. Present study is dedicated to assessing levels of change overtime in three distinct types of wetlands in Pakistan i.e. Indus delta a coastal wetland, Uchhali complex an inland wetland which are both protected sites while another site Nurri Lagoon which is not sheltered under any category of protected areas. Remotely sensed data has remarkable applications in change detection. Multitemporal Landsat images were used to map changes occurring from 2006 to 2016. Results reveal that wetland area has considerably decreased for all types. Both protected sites have experienced degradation though impact is comparatively lesser than unprotected Nurri lagoon. Significance of protection strategies cannot be denied, it is recommended that mere declaration of a site protected area is not sufficient. It is equally important to control non-point pollutants and ensuring the compliance of conservation strategy.

  15. Settlement patterns and communication routes of the western Maya wetlands: An archaeological and remote-sensing survey, Chunchucmil, Yucatan, Mexico

    Science.gov (United States)

    Hixson, David R.

    This dissertation investigates the role of the seasonal wetlands in the political economy and subsistence strategies of the ancient Maya of Chunchucmil, Yucatan, Mexico. A combination of pedestrian surveys and remote-sensing tasks were performed in order to better understand the settlement patterns and potential communication routes in and through the wetlands between Chunchucmil and the Gulf of Mexico. These western wetlands had been proposed as the principal avenue for interregional trade between coastal merchants and inland consumers, yet were thought to be uninhabited and uncultivable. Following the survey tasks outlined in this dissertation, these wetlands were found to contain an abundance of archaeological settlements and features indicating habitation, utilization, and trade throughout this diverse ecological zone. The remote-sensing platforms utilized in this study include both multispectral (Landsat) and synthetic aperture radar (AirSAR), combined with additional remotely sensed resources. One of the goals of this survey was to test the capabilities of these two sensors for the direct detection of archaeological features from air and space. The results indicate that Landsat can be highly successful at detecting site location and measuring site size under certain environmental conditions. The Airborne Synthetic Aperture Radar proved to be adept at detecting large mounded architecture within the Yucatecan karstic plain, but its further utility is hampered by limitations of resolution, scale, and land cover. One of the salient features of the landscape west of Chunchucmil is a network of stone pathways called andadores. These avenues through the wetlands outline a dendritic network of communication, trade, and extraction routes. The following dissertation places this network and its associated settlements (from suburban centers to diminutive camps) within their regional context, examining the roles they may have played in supporting a large mercantile

  16. Louisiana Coastal Wetlands Conservation Plan Boundary, Geographic NAD83, LDNR (1998) [conservation_plan_boundary_LDNR_1998

    Data.gov (United States)

    Louisiana Geographic Information Center — This is a polygon dataset depicting the areas of coastal wetlands in the state of Louisiana. This area encloses the tidally influenced coastal region three feet or...

  17. Anaerobic ammonium oxidation and its contribution to nitrogen removal in China’s coastal wetlands

    Science.gov (United States)

    Hou, Lijun; Zheng, Yanling; Liu, Min; Li, Xiaofei; Lin, Xianbiao; Yin, Guoyu; Gao, Juan; Deng, Fengyu; Chen, Fei; Jiang, Xiaofen

    2015-01-01

    Over the past several decades, human activities have caused substantial enrichment of reactive nitrogen in China’s coastal wetlands. Although anaerobic ammonium oxidation (anammox), the process of oxidizing ammonium into dinitrogen gas through the reduction of nitrite, is identified as an important process for removing reactive nitrogen, little is known about the dynamics of anammox and its contribution to nitrogen removal in nitrogen-enriched environments. Here, we examine potential rates of anammox and associate them with bacterial diversity and abundance across the coastal wetlands of China using molecular and isotope tracing techniques. High anammox bacterial diversity was detected in China’s coastal wetlands and included Candidatus Scalindua, Kuenenia, Brocadia, and Jettenia. Potential anammox rates were more closely associated with the abundance of anammox bacteria than to their diversity. Among all measured environmental variables, temperature was a key environmental factor, causing a latitudinal distribution of the anammox bacterial community composition, biodiversity and activity along the coastal wetlands of China. Based on nitrogen isotope tracing experiments, anammox was estimated to account for approximately 3.8–10.7% of the total reactive nitrogen removal in the study area. Combined with denitrification, anammox can remove 20.7% of the total external terrigenous inorganic nitrogen annually transported into China’s coastal wetland ecosystems. PMID:26494435

  18. Importance of Small Isolated Wetlands for Herpetofaunal Diversity in Managed, Young Growth Forests in the Coastal Plain of South Carolina

    International Nuclear Information System (INIS)

    Russell, K.R.; Guynn, D.C. Jr.; Hanlin, H.G.

    2002-01-01

    Assessment and comparison of richness, abundance and difference of herpetofauna at five small isolated wetlands located within a commercial forest landscape in the South Carolina Coastal Plain. Data indicates small isolated wetlands are focal points of herpetofaunal richness and abundance in managed coastal plain forest and contribute more to regional biodiversity than is implied by their small size or ephemeral hydrology

  19. U.S. Pacific coastal wetland resilience and vulnerability to sea-level rise

    Science.gov (United States)

    Thorne, Karen M.; MacDonald, Glen M.; Guntenspergen, Glenn R.; Ambrose, Richard F.; Buffington, Kevin J.; Dugger, Bruce D.; Freeman, Chase; Janousek, Christopher; Brown, Lauren N.; Rosencranz, Jordan A.; Homquist, James; Smol, John P.; Hargan, Kathryn; Takekawa, John Y.

    2018-01-01

    We used a first-of-its-kind comprehensive scenario approach to evaluate both the vertical and horizontal response of tidal wetlands to projected changes in the rate of sea-level rise (SLR) across 14 estuaries along the Pacific coast of the continental United States. Throughout the U.S. Pacific region, we found that tidal wetlands are highly vulnerable to end-of-century submergence, with resulting extensive loss of habitat. Using higher-range SLR scenarios, all high and middle marsh habitats were lost, with 83% of current tidal wetlands transitioning to unvegetated habitats by 2110. The wetland area lost was greater in California and Oregon (100%) but still severe in Washington, with 68% submerged by the end of the century. The only wetland habitat remaining at the end of the century was low marsh under higher-range SLR rates. Tidal wetland loss was also likely under more conservative SLR scenarios, including loss of 95% of high marsh and 60% of middle marsh habitats by the end of the century. Horizontal migration of most wetlands was constrained by coastal development or steep topography, with just two wetland sites having sufficient upland space for migration and the possibility for nearly 1:1 replacement, making SLR threats particularly high in this region and generally undocumented. With low vertical accretion rates and little upland migration space, Pacific coast tidal wetlands are at imminent risk of submergence with projected rates of rapid SLR.

  20. Leveraging Carbon Cycling in Coastal Wetlands for Habitat Conservation: Blue Carbon Policy Opportunities (Invited)

    Science.gov (United States)

    Sutton-Grier, A.

    2013-12-01

    Recent scientific studies suggest that the carbon sequestered and stored in coastal wetlands (specifically mangroves, salt marshes, and seagrass meadows) is an important, previously not well-recognized service provided by these ecosystems. Coastal wetlands have unique characteristics that make them incredibly efficient, natural carbon sinks with most carbon stored belowground in soils. Based on this new scientific evidence, there is growing interest in leveraging the carbon services of these habitats (termed 'blue carbon') to develop new policy opportunities to protect and restore coastal wetlands around the globe. The overall goal is to take full advantage of the carbon services of these habitats in order to ensure and maintain the many benefits provided to society by these habitats - including natural climate, food security, and storm protection benefits - and to enhance the resiliency of coastal communities and economies around the world. This presentation will give an update on some of the policy opportunities including: (1) examining how the implementation of U.S. federal policies can be expanded to include carbon services of ecosystems in order to improve management and decision making; (2) developing an international blue carbon community of science and practice to provide best practice guidance for protection and restoration of blue carbon habitats; and (3) developing innovative financing mechanisms for coastal conservation including carbon market credits for wetlands. Finally, the presentation will conclude by highlighting some of the most pressing blue carbon scientific gaps that need to be filled in order to support these developing policies.

  1. Preparing for Sea-level Rise: Conflicts and Opportunities in Coastal Wetlands Coexisting with Infrastructure

    Science.gov (United States)

    Rodriguez, J. F.; Saco, P. M.; Sandi, S. G.; Saintilan, N.; Riccardi, G.

    2017-12-01

    Even though on a large scale the sustainability and resilience of coastal wetlands to sea-level rise depends on the slope of the landscape and a balance between the rates of soil accretion and the sea-level rise, local man-made flow disturbances can have comparable effects. Coastal infrastructure controlling flow in the wetlands can pose an additional constraint on the adaptive capacity of these ecosystems, but can also present opportunities for targeted flow management to increase their resilience. Coastal wetlands in SE Australia are heavily managed and typically present infrastructure including flow control devices. How these flow control structures are operated respond to different ecological conservation objectives (i.e. bird, frog or fish habitat) that can sometimes be mutually exclusive. For example, promoting mangrove establishment to enhance fish habitat results in saltmarsh decline thus affecting bird habitat. Moreover, sea-level rise will change hydraulic conditions in wetlands and may result in some flow control structures and strategies becoming obsolete or even counterproductive. In order to address these problems and in support of future management of flows in coastal wetlands, we have developed a predictive tool for long-term wetland evolution that incorporates the effects of infrastructure and other perturbations to the tidal flow within the wetland (i.e. vegetation resistance) and determines how these flow conditions affect vegetation establishment and survival. We use the model to support management and analyse different scenarios of sea-level rise and flow control measures aimed at preserving bird habitat. Our results show that sea-level rise affects the efficiency of management measures and in some cases may completely override their effect. It also shows the potential of targeted flow management to compensate for the effects of sea-level rise.

  2. Causal mechanisms of soil organic matter decomposition: Deconstructing salinity and flooding impacts in coastal wetlands

    Science.gov (United States)

    Stagg, Camille L.; Schoolmaster, Donald; Krauss, Ken W.; Cormier, Nicole; Conner, William H.

    2017-01-01

    Coastal wetlands significantly contribute to global carbon storage potential. Sea-level rise and other climate change-induced disturbances threaten coastal wetland sustainability and carbon storage capacity. It is critical that we understand the mechanisms controlling wetland carbon loss so that we can predict and manage these resources in anticipation of climate change. However, our current understanding of the mechanisms that control soil organic matter decomposition, in particular the impacts of elevated salinity, are limited, and literature reports are contradictory. In an attempt to improve our understanding of these complex processes, we measured root and rhizome decomposition and developed a causal model to identify and quantify the mechanisms that influence soil organic matter decomposition in coastal wetlands that are impacted by sea-level rise. We identified three causal pathways: 1) a direct pathway representing the effects of flooding on soil moisture, 2) a direct pathway representing the effects of salinity on decomposer microbial communities and soil biogeochemistry, and 3) an indirect pathway representing the effects of salinity on litter quality through changes in plant community composition over time. We used this model to test the effects of alternate scenarios on the response of tidal freshwater forested wetlands and oligohaline marshes to short- and long-term climate-induced disturbances of flooding and salinity. In tidal freshwater forested wetlands, the model predicted less decomposition in response to drought, hurricane salinity pulsing, and long-term sea-level rise. In contrast, in the oligohaline marsh, the model predicted no change in response to sea-level rise, and increased decomposition following a drought or a hurricane salinity pulse. Our results show that it is critical to consider the temporal scale of disturbance and the magnitude of exposure when assessing the effects of salinity intrusion on carbon mineralization in coastal

  3. Characterization of labile organic carbon in coastal wetland soils of the Mississippi River deltaic plain: Relationships to carbon functionalities

    Energy Technology Data Exchange (ETDEWEB)

    Dodla, Syam K. [School of Plant, Environmental and Soil Sciences, Louisiana State Univ. Agricultural Center, Baton Rouge, LA 70803 (United States); Wang, Jim J., E-mail: jjwang@agcenter.lsu.edu [School of Plant, Environmental and Soil Sciences, Louisiana State Univ. Agricultural Center, Baton Rouge, LA 70803 (United States); DeLaune, Ronald D. [Department of Oceanography and Coastal Sciences, School of the Coast and Environment, Louisiana State University, Baton Rouge, LA 70803 (United States)

    2012-10-01

    Adequate characterization of labile organic carbon (LOC) is essential to the understanding of C cycling in soil. There has been very little evaluation about the nature of LOC characterizations in coastal wetlands, where soils are constantly influenced by different redox fluctuations and salt water intrusions. In this study, we characterized and compared LOC fractions in coastal wetland soils of the Mississippi River deltaic plain using four different methods including 1) aerobically mineralizable C (AMC), 2) cold water extractable C (CWEC), 3) hot water extractable C (HWEC), and 4) salt extractable C (SEC), as well as acid hydrolysable C (AHC) which includes both labile and slowly degradable organic C. Molecular organic C functional groups of these wetland soils were characterized by {sup 13}C solid-state nuclear magnetic resonance (NMR). The LOC and AHC increased with soil organic C (SOC) regardless of wetland soil type. The LOC estimates by four different methods were positively and significantly linearly related to each other (R{sup 2} = 0.62-0.84) and with AHC (R{sup 2} = 0.47-0.71). The various LOC fractions accounted for {<=} 4.3% of SOC whereas AHC fraction represented 16-49% of SOC. AMC was influenced positively by O/N-alkyl and carboxyl C but negatively by alkyl C, whereas CWEC and SEC fractions were influenced only positively by carboxyl C but negatively by alkyl C in SOC. On the other hand, HWEC fraction was found to be only influenced positively by carbonyl C, and AHC positively by O/N-alkyl and alkyl C but negatively by aromatic C groups in SOC. Overall these relations suggested different contributions of various molecular organic C moieties to LOC in these wetlands from those often found for upland soils. The presence of more than 50% non-acid hydrolysable C suggested the dominance of relatively stable SOC pool that would be sequestered in these Mississippi River deltaic plain coastal wetland soils. The results have important implications to the

  4. Improved coastal wetland mapping using very-high 2-meter spatial resolution imagery

    Science.gov (United States)

    McCarthy, Matthew J.; Merton, Elizabeth J.; Muller-Karger, Frank E.

    2015-08-01

    Accurate wetland maps are a fundamental requirement for land use management and for wetland restoration planning. Several wetland map products are available today; most of them based on remote sensing images, but their different data sources and mapping methods lead to substantially different estimations of wetland location and extent. We used two very high-resolution (2 m) WorldView-2 satellite images and one (30 m) Landsat 8 Operational Land Imager (OLI) image to assess wetland coverage in two coastal areas of Tampa Bay (Florida): Fort De Soto State Park and Weedon Island Preserve. An initial unsupervised classification derived from WorldView-2 was more accurate at identifying wetlands based on ground truth data collected in the field than the classification derived from Landsat 8 OLI (82% vs. 46% accuracy). The WorldView-2 data was then used to define the parameters of a simple and efficient decision tree with four nodes for a more exacting classification. The criteria for the decision tree were derived by extracting radiance spectra at 1500 separate pixels from the WorldView-2 data within field-validated regions. Results for both study areas showed high accuracy in both wetland (82% at Fort De Soto State Park, and 94% at Weedon Island Preserve) and non-wetland vegetation classes (90% and 83%, respectively). Historical, published land-use maps overestimate wetland surface cover by factors of 2-10 in the study areas. The proposed methods improve speed and efficiency of wetland map production, allow semi-annual monitoring through repeat satellite passes, and improve the accuracy and precision with which wetlands are identified.

  5. WETLAND CHANGE DETECTION IN PROTECTED AND UNPROTECTED INDUS COASTAL AND INLAND DELTA

    Directory of Open Access Journals (Sweden)

    M. H. Ali Baig

    2017-09-01

    Full Text Available Worth of wetland sites lies in their ecological importance. They enhance ecosystem via provision of ecological services like improving water quality, groundwater infiltration, flood risk reduction and biodiversity regulation. Like other parts of the world Pakistan is also facing wetlands degradation. Ecological and economic significance of wetlands was recognized officially in 1971 as Pakistan became signatory of Ramsar wetland convention. Wetlands provide habitat to species of ecological and economic importance. Despite being recognized for international importance, Ramsar figures state that almost half of Pakistan’s wetlands are at moderate or prominent level threat. Wetlands ecosystems are deteriorating at a rapid rate, if uncontrolled this trend may lead to substantial losses. Therefore, management of these resources demands regular monitoring. Present study is dedicated to assessing levels of change overtime in three distinct types of wetlands in Pakistan i.e. Indus delta a coastal wetland, Uchhali complex an inland wetland which are both protected sites while another site Nurri Lagoon which is not sheltered under any category of protected areas. Remotely sensed data has remarkable applications in change detection. Multitemporal Landsat images were used to map changes occurring from 2006 to 2016. Results reveal that wetland area has considerably decreased for all types. Both protected sites have experienced degradation though impact is comparatively lesser than unprotected Nurri lagoon. Significance of protection strategies cannot be denied, it is recommended that mere declaration of a site protected area is not sufficient. It is equally important to control non-point pollutants and ensuring the compliance of conservation strategy.

  6. Integrating ecosystem services and climate change responses in coastal wetlands development plans for Bangladesh

    NARCIS (Netherlands)

    Sarwar, M.H.; Hein, L.G.; Rip, F.I.; Dearing, J.A.

    2015-01-01

    This study explores the integration of ecosystem services and climate change adaptation in development plans for coastal wetlands in Bangladesh. A new response framework for adaptation is proposed, based on an empirical analysis and consultations with stakeholders, using a modified version of the

  7. Chapter 16 - conservation and use of coastal wetland forests in Louisiana

    Science.gov (United States)

    Stephen P. Faulkner; Jim L. Chambers; William H. Conner; Richard F. Keim; John W. Day; Emile S. Gardiner; Melinda S. Hughes; Sammy L. King; Kenneth W. McLeod; Craig A. Miller; J. Andrew Nyman; Gary P. Shaffer

    2007-01-01

    The natural ecosystems of coastal Louisiana reflect the underlying geomorphic processes responsible for their formation. The majority of Louisiana's wetland forests are found in the lower reaches of the Mississipp Alluvial Valley and the Deltaic Plain. The sediments, water, and energy of the Mississippi River have shaped the Deltaic Plain as natural deltas have...

  8. 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...

  9. Assessment of coastal wetland resources of central west coast, India, using LANDSAT data

    Digital Repository Service at National Institute of Oceanography (India)

    Jagtap, T.G.; Naik, S.; Nagle, V.L.

    The part of central west coast (Maharashtra and Goa) of India has been classified and quantified for coastal wetlands using LANDSAT data of 1985-86. The classification accuracy of the maps and area estimates achieved was 84% at 90% confidence level...

  10. Wetland education through cooperative programs between coastal Carolina University and Horry County public schools

    Science.gov (United States)

    Sharon L. Gilman

    2000-01-01

    Horry County, in the Coastal Plain of South Carolina, isapproximately 50 percent wetlands. The Waccamaw Region (Horry, Georgetown, and Williamsburg Counties) has experienced a 58-percent population increase during theperiod from 1960 to 1990. Population growth trends suggest that from 1990 to 2020, the total daily population will increase by 125 percent, representing...

  11. Organic Carbon and Trace Element Cycling in a River-Dominated Tidal Coastal Wetland System (Tampa Bay, FL, USA)

    Science.gov (United States)

    Moyer, R. P.; Smoak, J. M.; Engelhart, S. E.; Powell, C. E.; Chappel, A. R.; Gerlach, M. J.; Kemp, A.; Breithaupt, J. L.

    2016-02-01

    Tampa Bay is the largest open water, river-fed estuary in Florida (USA), and is characterized by the presence of both mangrove and salt marsh ecosystems. Both coastal wetland systems, and small rivers such as the ones draining into Tampa Bay have historically been underestimated in terms of their role in the global carbon and elemental cycles. Climate change and sea-level rise (SLR) are major threats in Tampa Bay and stand to disrupt hydrologic cycles, compromising sediment accumulation and the rate of organic carbon (OC) burial. This study evaluates organic carbon content, sediment accumulation, and carbon burial rates in salt marsh and mangrove ecosystems, along with measurements of fluxes of dissolved OC (DOC) and trace elements in the water column of the Little Manatee River (LMR) in Tampa Bay. The characterization of OC and trace elements in tidal rivers and estuaries is critical for quantitatively constraining these systems in local-to-regional scale biogeochemical budgets, and provide insight into biogeochemical processes occurring with the estuary and adjacent tidal wetlands. Material fluxes of DOC and trace elements were tied to discharge irrespective of season, and the estuarine habitats removed 15-65% of DOC prior to export to Tampa Bay and the Gulf of Mexico. Thus, material is available for cycling and burial within marsh and mangrove peats, however, LMR mangrove peats have higher OC content and burial rates than adjacent salt marsh peats. Sedimentary accretion rates in LMR marshes are not currently keeping pace with SLR, thus furthering the rapid marsh-to-mangrove conversions that have been seen in Tampa Bay over the past half-century. Additionally, wetlands in Tampa Bay tend to have a lower rate of carbon burial than other Florida tidal wetlands, demonstrating their high sensitivity to climate change and SLR.

  12. Stimulating a Great Lakes coastal wetland seed bank using portable cofferdams: implications for habitat rehabilitation

    Science.gov (United States)

    Kowalski, K.P.; Wilcox, D.A.; Wiley, M.J.

    2009-01-01

    Coastal wetland seed banks exposed by low lake levels or through management actions fuel the reestablishment of emergent plant assemblages (i.e., wetland habitat) critical to Great Lakes aquatic biota. This project explored the effectiveness of using portable, water-filled cofferdams as a management tool to promote the natural growth of emergent vegetation from the seed bank in a Lake Erie coastal wetland. A series of dams stretching approximately 450??m was installed temporarily to isolate hydrologically a 10-ha corner of the Crane Creek wetland complex from Lake Erie. The test area was dewatered in 2004 to mimic a low-water year, and vegetation sampling characterized the wetland seed bank response at low, middle, and high elevations in areas open to and protected from bird and mammal herbivory. The nearly two-month drawdown stimulated a rapid seed-bank-driven response by 45 plant taxa. Herbivory had little effect on plant species richness, regardless of the location along an elevation gradient. Inundation contributed to the replacement of immature emergent plant species with submersed aquatic species after the dams failed and were removed prematurely. This study revealed a number of important issues that must be considered for effective long-term implementation of portable cofferdam technology to stimulate wetland seed banks, including duration of dewatering, product size, source of clean water, replacement of damaged dams, and regular maintenance. This technology is a potentially important tool in the arsenal used by resource managers seeking to rehabilitate the functions and values of Great Lakes coastal wetland habitats.

  13. Eten's Coastal Wetland, its geomorphology, water quality and biodiversity

    Science.gov (United States)

    Rojas Carbajal, T. V.; Bartl, K.; Loayza Muro, R.; Abad, J. D.

    2017-12-01

    The Eten's wetland is located in the lower part of the Chancay-Lambayeque River basin at the Peruvian coast. This wetland contains salt and fresh marshes, swamps, lagoons and an estuary which is the result of Reque River's morphodynamics. It provides a great source of totora (Schoenoplectus californicus), a native plant that is used for knitting hats which are an ancient cultural expression in Lambayeque. UNESCO recognized this wetland as one of the ecosystems with the greatest biodiversity along the South Pacific Coast, providing a unique habitat for migratory birds, such as the Peruvian Tern (Sternula lorata). This bird has been classified as endangered in 2005, by the International Union for Conservation of Nature (IUCN). When the area of a wetland is reduced, the resting point function is affected leading to loss in biodiversity due to the habitat conditions are not the same. In 2005, Lambayeque's government established an area of 1377 Ha in order to preserve wetland's ecosystem and Eten's archeological value but wet areas were reduced to 200 Ha. This reduction was promoted by agriculture, urbanization and an inadequate urban waste disposal. The scope of the study is to assess the environmental impacts that affect Eten's wetland. Preliminary results of an assessment with remote sensing indicate that: 1) the Reque River's geomorphic activity was reduced by urbanization, thus, the connection between surface water bodies has been lost, leading the drying out of ponds, 2) the conversion of wet areas to agricultural land, and 3) the natural interaction between the Reque River and the Pacific Ocean was modified due to water control upstream, resulting in a dryer wetland during the last years. Furthermore, the aquatic biodiversity of the wetland was assessed through a biomonitoring method in order to study the impact of water contamination. Four benthic macroinvertebrate Families (Hydrophilidae, Baetidae, Planorbidae and Palaemonidae) were found. The quality of the

  14. Transplanting native dominant plants to facilitate community development in restored coastal plain wetlands.

    Energy Technology Data Exchange (ETDEWEB)

    De Steven, Diane; Sharitz, Rebecca R.

    2007-12-01

    Abstract: Drained depressional wetlands are typically restored by plugging ditches or breaking drainage tiles to allow recovery of natural ponding regimes, while relying on passive recolonization from seed banks and dispersal to establish emergent vegetation. However, in restored depressions of the southeastern United States Coastal Plain, certain characteristic rhizomatous graminoid species may not recolonize because they are dispersal-limited and uncommon or absent in the seed banks of disturbed sites. We tested whether selectively planting such wetland dominants could facilitate restoration by accelerating vegetative cover development and suppressing non-wetland species. In an operational-scale project in a South Carolina forested landscape, drained depressional wetlands were restored in early 2001 by completely removing woody vegetation and plugging surface ditches. After forest removal, tillers of two rhizomatous wetland grasses (Panicum hemitomon, Leersia hexandra) were transplanted into singlespecies blocks in 12 restored depressions that otherwise were revegetating passively. Presence and cover of all plant species appearing in planted plots and unplanted control plots were recorded annually. We analyzed vegetation composition after two and four years, during a severe drought (2002) and after hydrologic recovery (2004). Most grass plantings established successfully, attaining 15%–85% cover in two years. Planted plots had fewer total species and fewer wetland species compared to control plots, but differences were small. Planted plots achieved greater total vegetative cover during the drought and greater combined cover of wetland species in both years. By 2004, planted grasses appeared to reduce cover of non-wetland species in some cases, but wetter hydrologic conditions contributed more strongly to suppression of non-wetland species. Because these two grasses typically form a dominant cover matrix in herbaceous depressions, our results indicated that

  15. Coastal Carbon Dynamics as a New Chapter in SOCCR2: Tidal Wetlands and Estuaries

    Science.gov (United States)

    Windham-Myers, L.; Megonigal, P.; Cai, W. J.; Hopkinson, C.; Wang, A. Z.; Andersson, A. J.; Hinson, A.; Lagomasino, D.; Peteet, D. M.; Giri, C. P.; Howard, J.; Tang, J.; Crosswell, J.; Martin Hernandez-Ayon, J. M.; Dunton, K. H.; Kroeger, K. D.; Paulsen, M. L.; Allison, M. A.; Siedlecki, S. A.; Alin, S. R.; Hu, X.; Tzortziou, M.; Najjar, R.; Schafer, K. V.; Watson, E.; Pidgeon, E.

    2016-12-01

    Estuaries and tidal wetlands have been identified as distinct landscape elements for carbon cycling, worthy of a chapter in the pending State of the Carbon Cycle Report - version 2. Despite relatively small aerial coverage compared to other subsystems, tidal wetlands and estuaries have the greatest influence on carbon dynamics of any coastal ocean subsystem. As conduits that filter all material passing between land and the sea, they also exhibit the highest transfer rates of CO2 with the atmosphere of any of the coastal ocean subsystems. Carbon dynamics in estuaries and wetlands are constantly changing, reflecting geomorphic and ecological responses to long and short-term perturbations in external drivers such as sea-level rise, climate change, nutrient loading and land-use change. The influence of these drivers are profound in coastal systems, often more so than in inland wetlands or open ocean environments, and thus require distinct attention to patterns and processes associated with coastal ecosystem functioning, including carbon sequestration services in tidal wetland soils. This new chapter focusses on data sources available in North America to: (1) assess the current state of carbon stocks and fluxes in coastal settings, (2) document understanding of drivers associated with significant fluxes and stocks, and (3) synthesize carbon dynamics from a global context to regional perspectives (East, West, Gulf and high-latitude coastlines). Insights from remote sensing, in situ field data, and numerical models have advanced our ability to monitor and project carbon cycling in this dynamic and narrow fringe at the land-ocean interface. This synthetic chapter will address how these advances can help in decision making, as well as address remaining gaps in our knowledge and monitoring capabilities for these diverse and productive habitats.

  16. Denitrification potential and its relation to organic carbon quality in three coastal wetland soils

    Energy Technology Data Exchange (ETDEWEB)

    Dodla, Syam K. [School of Plant, Environmental and Soil Sciences, Louisiana State Univ. Agricultural Center, Baton Rouge, LA 70803 (United States); Wang, Jim J. [School of Plant, Environmental and Soil Sciences, Louisiana State Univ. Agricultural Center, Baton Rouge, LA 70803 (United States)], E-mail: jjwang@agctr.lsu.edu; DeLaune, Ron D. [Wetland Biogeochemistry Institute, School of the Coast and Environment, Louisiana State University, Baton Rouge, LA 70803 (United States); Cook, Robert L. [Chemistry Department, Louisiana State University, Baton Rouge, LA 70803 (United States)

    2008-12-15

    Capacity of a wetland to remove nitrate through denitrification is controlled by its physico-chemical and biological characteristics. Understanding these characteristics will help better to guide beneficial use of wetlands in processing nitrate. This study was conducted to determine the relationship between soil organic carbon (SOC) quality and denitrification rate in Louisiana coastal wetlands. Composite soil samples of different depths were collected from three different wetlands along a salinity gradient, namely, bottomland forest swamp (FS), freshwater marsh (FM), and saline marsh (SM) located in the Barataria Basin estuary. Potential denitrification rate (PDR) was measured by acetylene inhibition method and distribution of carbon (C) moieties in organic C was determined by {sup 13}C solid-state NMR. Of the three wetlands, the FM soil profile exhibited the highest PDR on both unit weight and unit volume basis as compared to FS and SM. The FM also tended to yield higher amount of N{sub 2}O as compared to the FS and SM especially at earlier stages of denitrification, suggesting incomplete reduction of NO{sub 3}{sup -} at FM and potential for emission of N{sub 2}O. Saline marsh soil profile had the lowest PDR on the unit volume basis. Increasing incubation concentration from 2 to 10 mg NO{sub 3}{sup -}-N L{sup -1} increased PDR by 2 to 6 fold with the highest increase in the top horizons of FS and SM soils. Regression analysis showed that across these three wetland systems, organic C has significant effect in regulating PDR. Of the compositional C moieties, polysaccharides positively influenced denitrification rate whereas phenolics (likely phenolic adehydes and ketonics) negatively affected denitrification rate in these wetland soils. These results could have significant implication in integrated assessment and management of wetlands for treating nutrient-rich biosolids and wastewaters, non-point source agricultural runoff, and nitrate found in the diverted

  17. Denitrification potential and its relation to organic carbon quality in three coastal wetland soils

    International Nuclear Information System (INIS)

    Dodla, Syam K.; Wang, Jim J.; DeLaune, Ron D.; Cook, Robert L.

    2008-01-01

    Capacity of a wetland to remove nitrate through denitrification is controlled by its physico-chemical and biological characteristics. Understanding these characteristics will help better to guide beneficial use of wetlands in processing nitrate. This study was conducted to determine the relationship between soil organic carbon (SOC) quality and denitrification rate in Louisiana coastal wetlands. Composite soil samples of different depths were collected from three different wetlands along a salinity gradient, namely, bottomland forest swamp (FS), freshwater marsh (FM), and saline marsh (SM) located in the Barataria Basin estuary. Potential denitrification rate (PDR) was measured by acetylene inhibition method and distribution of carbon (C) moieties in organic C was determined by 13 C solid-state NMR. Of the three wetlands, the FM soil profile exhibited the highest PDR on both unit weight and unit volume basis as compared to FS and SM. The FM also tended to yield higher amount of N 2 O as compared to the FS and SM especially at earlier stages of denitrification, suggesting incomplete reduction of NO 3 - at FM and potential for emission of N 2 O. Saline marsh soil profile had the lowest PDR on the unit volume basis. Increasing incubation concentration from 2 to 10 mg NO 3 - -N L -1 increased PDR by 2 to 6 fold with the highest increase in the top horizons of FS and SM soils. Regression analysis showed that across these three wetland systems, organic C has significant effect in regulating PDR. Of the compositional C moieties, polysaccharides positively influenced denitrification rate whereas phenolics (likely phenolic adehydes and ketonics) negatively affected denitrification rate in these wetland soils. These results could have significant implication in integrated assessment and management of wetlands for treating nutrient-rich biosolids and wastewaters, non-point source agricultural runoff, and nitrate found in the diverted Mississippi River water used for coastal

  18. Local and regional scale exchanges of dissolved organic carbon (DOC) between tidal wetlands and their adjacent coastal waters

    Science.gov (United States)

    Osburn, C. L.; Joshi, I.; Lebrasse, M. C.; Oviedo-Vargas, D.; Bianchi, T. S.; Bohnenstiehl, D. R.; D'Sa, E. J.; He, R.; Ko, D.; Arellano, A.; Ward, N. D.

    2017-12-01

    The contribution of blue carbon from tidal wetlands to the coastal ocean in the form of dissolved organic carbon (DOC) represents a terrestrial-aquatic linkage of increasing importance. DOC flux results will be presented from local (tidal creek) and regional (bays) scale studies in which various combinations of field observations, ocean-color satellite observations, and the outputs of high-resolution hydrodynamic models were used to estimate DOC export. The first project was located in Bald Head Creek, a tributary to the Cape Fear River estuary in eastern North Carolina (NC). DOC fluxes were computed using a bathymetric data collected via unmanned surface vehicle (USV) and a numerical hydrodynamic model (SCHISM) based on the relationships between colored dissolved organic matter (CDOM) absorption, DOC concentration, and salinity taken from field observations. Model predictions estimated an annual net export of DOC at 54 g C m-2 yr-1 from the tidal creek to the adjacent estuary. Carbon stable isotope (δ13C) values were used to estimate the contribution of wetland carbon to this export. In the second project, DOC fluxes from the Apalachicola Bay, FL, Barataria Bay, LA, were based on the development of algorithms between DOC and CDOM absorption derived from the VIIRS ocean color sensor. The Navy Coastal Ocean Model (NCOM) was used to compute salt flux estimates from each bay to the Louisiana-Texas shelf. The relationship between salinity and CDOM was used to estimate net annual DOC exports of 8.35 x 106 g C m-2 y-1 (Apalachicola Bay) and 7.14 x 106 g C m-2 yr-1 (Barataria Bay). These values approximate 13% and 9% of the annual loads of DOC from the Mississippi River to the Gulf of Mexico, respectively. CDOM and lignin were used in a mixing model to estimate wetland-derived DOC were 2% for Apalachicola Bay and 13% for Barataria Bay, the latter having one of the highest rates of relative sea level rise in North America. Results from our project demonstrated the utility

  19. Study of Evacuation Behavior of Coastal Gulf of Mexico Residents

    OpenAIRE

    Bhattacharjee, Sanjoy; Petrolia, Daniel R.; Hanson, Terrill R.

    2009-01-01

    In this study, we investigate the link between hurricane characteristics, demographics of the Coastal Gulf of Mexico residents, including their household location, and their respective evacuation behavior. Our study is significantly different from the previously made studies on hurricane evacuation behavior in two ways. At first, the research data is collected through recording responses to a series of hypothetical situations which are quite identical to the set of information that people are...

  20. Dynamics of carbon sequestration in a coastal wetland using radiocarbon measurements

    Science.gov (United States)

    Choi, Yonghoon; Wang, Yang

    2004-12-01

    Coastal wetlands are sensitive to global climate change and may play an important role in the global carbon cycle. However, the dynamics of carbon (C) cycling in coastal wetlands and its response to sea level change associated with global warming is still poorly understood. In this study, we estimated the long-term and short-term rates of C accumulation, using C and C isotopic measurements of peat cores collected along a soil chronosequence, in a coastal wetland in north Florida. The long-term C accumulation rates determined by examining the C inventory and the radioactive decay of radiocarbon as a function of depth in the peat cores decrease with time from ˜130 ± 9 g C/m2/yr over the last century to ˜13 ± 2 g C/m2/yr over the millennium timescale. The short-term C accumulation rates estimated by examining the differences in the radiocarbon and C contents of the surfacial peat between archived (1985, 1988) and present (1996 and 1997) samples range from 42 to 193 g C/m2/yr in low marsh, from 18 to 184 g C/m2/yr in middle marsh, and from -50 to 181 g C/m2/yr in high marsh. The high end-values of our estimated short-term C accumulation rates are comparable to the estimated rates of C sequestration in coastal wetlands reported by [2003], but are significantly higher than our estimated long-term rates in the marshes and are also much higher than the published rates of C sequestration in northern peatlands. The higher recent rates of C accumulation in coastal marshes, in comparison with the longer-term rates, are due to slow but continuous decomposition of organic matter in the peat over time. However, other factors such as increased primary production in the coastal wetland over the last decades or century, due to a rise in mean sea level and/or CO2 and nitrogen fertilization effect, could also have contributed to the large difference between the recent and longer-term rates. Our data indicate that salt marshes in this area have been and continue to be a sink for

  1. Controls of Carbon Preservation in Coastal Wetlands of Texas: Mangrove vs. Saltmarsh Ecosystems

    Science.gov (United States)

    Sterne, A. M. E.; Louchouarn, P.; Norwood, M. J.; Kaiser, K.

    2014-12-01

    The estimated magnitude of the carbon (C) stocks contained in the first meter of US coastal wetland soils represents ~10% of the entire C stock in US soils (4 vs. 52 Pg, respectively). Because this stock extends to several meters below the surface for many coastal wetlands, it becomes paramount to understand the fate of C under ecosystem shifts, varying natural environmental constraints, and changing land use. In this project we analyze total hydrolysable carbohydrates, amino acids, phenols and stable isotopic data (δ13C) at two study sites located on the Texas coastline to investigate chemical compositions and the stage of decomposition in mangrove and marsh grass dominated wetlands. Carbohydrates are used as specific decomposition indicators of the polysaccharide component of wetland plants, whereas amino acids are used to identify the contribution of microbial biomass, and acid/aldehyde ratios of syringyl (S) and vanillyl (V) phenols (Ac/AlS,V) follow the decomposition of lignin. Preliminary results show carbohydrates account for 30-50 % of organic carbon in plant litter and surface sediments at both sites. Sharp declines of carbohydrate yields with depth occur parallel to increasing Ac/AlS,V ratios indicating substantial decomposition of both the polysaccharide and lignin components of litter detritus. Ecological differences (between marsh grass and mangrove dominated wetlands) are discussed to better constrain the role of litter biochemistry and ecological shifts on C preservation in these anoxic environments.

  2. Phosphorus storage and mobilization in coastal Phragmites wetlands: Influence of local-scale hydrodynamics

    Science.gov (United States)

    Karstens, Svenja; Buczko, Uwe; Glatzel, Stephan

    2016-04-01

    Coastal Phragmites wetlands are at the interface between terrestrial and aquatic ecosystems and are of paramount importance for nutrient regulation. They can act both as sinks and sources for phosphorus, depending on environmental conditions, sediment properties as well as on antecedent nutrient loading and sorption capacity of the sediments. The Darss-Zingst Bodden Chain is a shallow lagoon system at the German Baltic Sea coast with a long eutrophication history. It is lined almost at its entire length by reed wetlands. In order to elucidate under which conditions these wetlands act as sources or sinks for phosphorus, in-situ data of chemo-physical characteristics of water and sediment samples were combined with hydrodynamic measurements and laboratory experiments. Small-scale basin structures within the wetland serve as sinks for fine-grained particles rich in phosphorus, iron, manganese and organic matter. Without turbulent mixing the bottom water and the sediment surface lack replenishment of oxygen. During stagnant periods with low water level, low turbulence and thus low-oxygen conditions phosphorus from the sediments is released. But the sediments are capable of becoming sinks again once oxygen is resupplied. A thin oxic sediment surface layer rich in iron and manganese adsorbs phosphorus quickly. We demonstrate that sediments in coastal Phragmites wetlands can serve both as sources and sinks of soluble reactive phosphorus on a very short time-scale, depending on local-scale hydrodynamics and the state of the oxic-anoxic sediment interface.

  3. 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.

  4. The present and future role of coastal wetland vegetation in protecting shorelines: Answering recent challenges to the paradigm

    Science.gov (United States)

    Gedan, Keryn B.; Kirwan, Matthew L.; Wolanski, Eric; Barbier, Edward B.; Silliman, Brian R.

    2011-01-01

    For more than a century, coastal wetlands have been recognized for their ability to stabilize shorelines and protect coastal communities. However, this paradigm has recently been called into question by small-scale experimental evidence. Here, we conduct a literature review and a small meta-analysis of wave attenuation data, and we find overwhelming evidence in support of established theory. Our review suggests that mangrove and salt marsh vegetation afford context-dependent protection from erosion, storm surge, and potentially small tsunami waves. In biophysical models, field tests, and natural experiments, the presence of wetlands reduces wave heights, property damage, and human deaths. Meta-analysis of wave attenuation by vegetated and unvegetated wetland sites highlights the critical role of vegetation in attenuating waves. Although we find coastal wetland vegetation to be an effective shoreline buffer, wetlands cannot protect shorelines in all locations or scenarios; indeed large-scale regional erosion, river meandering, and large tsunami waves and storm surges can overwhelm the attenuation effect of vegetation. However, due to a nonlinear relationship between wave attenuation and wetland size, even small wetlands afford substantial protection from waves. Combining man-made structures with wetlands in ways that mimic nature is likely to increase coastal protection. Oyster domes, for example, can be used in combination with natural wetlands to protect shorelines and restore critical fishery habitat. Finally, coastal wetland vegetation modifies shorelines in ways (e.g. peat accretion) that increase shoreline integrity over long timescales and thus provides a lasting coastal adaptation measure that can protect shorelines against accelerated sea level rise and more frequent storm inundation. We conclude that the shoreline protection paradigm still stands, but that gaps remain in our knowledge about the mechanistic and context-dependent aspects of shoreline

  5. Fishprint of Coastal Fisheries in Jalisco, Mexico

    Directory of Open Access Journals (Sweden)

    Myrna Leticia Bravo-Olivas

    2014-12-01

    Full Text Available Coastal fisheries contribute to global food security, since fish are an important source of protein for many coastal communities in the world. However, they are constrained by problems, such as weak management of fisheries and overfishing. Local communities perceive that they are fishing less, as in other fisheries in the world. The aim of this study was to evaluate the fisheries sustainability in the Jalisco coast through the fishing footprint, or fishprint (FP, based on the primary productivity required (PPR and the appropriated surface by the activity (biocapacity. The total catch was 20,448.2 metric tons from 2002–2012, and the average footprint was calculated to be 65,458 gha/year, a figure that quadrupled in a period of 10 years; the biocapacity decreased, and the average trophic level of catches was 3.1, which implies that it has remained at average levels, resulting in a positive balance between biocapacity and ecological footprint. Therefore, under this approach, the fishing activity is sustainable along the coast of Jalisco.

  6. Influence of seasonal variations in sea level on the salinity regime of a coastal groundwater-fed wetland.

    Science.gov (United States)

    Wood, Cameron; Harrington, Glenn A

    2015-01-01

    Seasonal variations in sea level are often neglected in studies of coastal aquifers; however, they may have important controls on processes such as submarine groundwater discharge, sea water intrusion, and groundwater discharge to coastal springs and wetlands. We investigated seasonal variations in salinity in a groundwater-fed coastal wetland (the RAMSAR listed Piccaninnie Ponds in South Australia) and found that salinity peaked during winter, coincident with seasonal sea level peaks. Closer examination of salinity variations revealed a relationship between changes in sea level and changes in salinity, indicating that sea level-driven movement of the fresh water-sea water interface influences the salinity of discharging groundwater in the wetland. Moreover, the seasonal control of sea level on wetland salinity seems to override the influence of seasonal recharge. A two-dimensional variable density model helped validate this conceptual model of coastal groundwater discharge by showing that fluctuations in groundwater salinity in a coastal aquifer can be driven by a seasonal coastal boundary condition in spite of seasonal recharge/discharge dynamics. Because seasonal variations in sea level and coastal wetlands are ubiquitous throughout the world, these findings have important implications for monitoring and management of coastal groundwater-dependent ecosystems. © 2014, National Ground Water Association.

  7. Derivation of Ground Surface and Vegetation in a Coastal Florida Wetland with Airborne Laser Technology

    Science.gov (United States)

    Raabe, Ellen A.; Harris, Melanie S.; Shrestha, Ramesh L.; Carter, William E.

    2008-01-01

    The geomorphology and vegetation of marsh-dominated coastal lowlands were mapped from airborne laser data points collected on the Gulf Coast of Florida near Cedar Key. Surface models were developed using low- and high-point filters to separate ground-surface and vegetation-canopy intercepts. In a non-automated process, the landscape was partitioned into functional landscape units to manage the modeling of key landscape features in discrete processing steps. The final digital ground surface-elevation model offers a faithful representation of topographic relief beneath canopies of tidal marsh and coastal forest. Bare-earth models approximate field-surveyed heights by + 0.17 m in the open marsh and + 0.22 m under thick marsh or forest canopy. The laser-derived digital surface models effectively delineate surface features of relatively inaccessible coastal habitats with a geographic coverage and vertical detail previously unavailable. Coastal topographic details include tidal-creek tributaries, levees, modest topographic undulations in the intertidal zone, karst features, silviculture, and relict sand dunes under coastal-forest canopy. A combination of laser-derived ground-surface and canopy-height models and intensity values provided additional mapping capabilities to differentiate between tidal-marsh zones and forest types such as mesic flatwood, hydric hammock, and oak scrub. Additional derived products include fine-scale shoreline and topographic profiles. The derived products demonstrate the capability to identify areas of concern to resource managers and unique components of the coastal system from laser altimetry. Because the very nature of a wetland system presents difficulties for access and data collection, airborne coverage from remote sensors has become an accepted alternative for monitoring wetland regions. Data acquisition with airborne laser represents a viable option for mapping coastal topography and for evaluating habitats and coastal change on marsh

  8. HYPERSPECTRAL REMOTE SENSING, GPS, AND GIS APPLICATIONS IN OPPORTUNISTIC PLANT SPECIES MONITORING OF GREAT LAKES COASTAL WETLANDS

    Science.gov (United States)

    Coastal wetlands of the Laurentian Great Lakes (LGL) are among the most fragmented and disturbed ecosystems of the world, with a long history of human-induced disturbance. LGL wetlands have undergone losses in the biological diversity that coincides with an increase in the presen...

  9. A conceptual hydrologic model for a forested Carolina bay depressional wetland on the Coastal Plain of South Carolina, USA

    Science.gov (United States)

    Jennifer E. Pyzoha; Timothy J. Callahan; Ge Sun; Carl C. Trettin; Masato Miwa

    2008-01-01

    This paper describes how climate influences the hydrology of an ephemeral depressional wetland. Surface water and groundwater elevation data were collected for 7 years in a Coastal Plain watershed in South Carolina USA containing depressional wetlands, known as Carolina bays. Rainfall and temperature data were compared with water-table well and piezometer data in and...

  10. Beyond just sea-level rise: Considering macroclimatic drivers within coastal wetland vulnerability assessments to climate change

    Science.gov (United States)

    Osland, Michael J.; Enwright, Nicholas M.; Day, Richard H.; Gabler, Christopher A.; Stagg, Camille L.; Grace, James B.

    2016-01-01

    Due to their position at the land-sea interface, coastal wetlands are vulnerable to many aspects of climate change. However, climate change vulnerability assessments for coastal wetlands generally focus solely on sea-level rise without considering the effects of other facets of climate change. Across the globe and in all ecosystems, macroclimatic drivers (e.g., temperature and rainfall regimes) greatly influence ecosystem structure and function. Macroclimatic drivers have been the focus of climate-change related threat evaluations for terrestrial ecosystems, but largely ignored for coastal wetlands. In some coastal wetlands, changing macroclimatic conditions are expected to result in foundation plant species replacement, which would affect the supply of certain ecosystem goods and services and could affect ecosystem resilience. As examples, we highlight several ecological transition zones where small changes in macroclimatic conditions would result in comparatively large changes in coastal wetland ecosystem structure and function. Our intent in this communication is not to minimize the importance of sea-level rise. Rather, our overarching aim is to illustrate the need to also consider macroclimatic drivers within vulnerability assessments for coastal wetlands.

  11. Beyond just sea-level rise: considering macroclimatic drivers within coastal wetland vulnerability assessments to climate change.

    Science.gov (United States)

    Osland, Michael J; Enwright, Nicholas M; Day, Richard H; Gabler, Christopher A; Stagg, Camille L; Grace, James B

    2016-01-01

    Due to their position at the land-sea interface, coastal wetlands are vulnerable to many aspects of climate change. However, climate change vulnerability assessments for coastal wetlands generally focus solely on sea-level rise without considering the effects of other facets of climate change. Across the globe and in all ecosystems, macroclimatic drivers (e.g., temperature and rainfall regimes) greatly influence ecosystem structure and function. Macroclimatic drivers have been the focus of climate change-related threat evaluations for terrestrial ecosystems, but largely ignored for coastal wetlands. In some coastal wetlands, changing macroclimatic conditions are expected to result in foundation plant species replacement, which would affect the supply of certain ecosystem goods and services and could affect ecosystem resilience. As examples, we highlight several ecological transition zones where small changes in macroclimatic conditions would result in comparatively large changes in coastal wetland ecosystem structure and function. Our intent in this communication is not to minimize the importance of sea-level rise. Rather, our overarching aim is to illustrate the need to also consider macroclimatic drivers within vulnerability assessments for coastal wetlands. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  12. Diversity and composition of sediment bacteria in subtropical coastal wetlands of North Stradbroke Island, Queensland, Australia

    Science.gov (United States)

    Chuvochina, Maria; Sampayo, Eugenia; Welti, Nina; Hayes, Matthew; Lu, Yang; Lovelock, Catherine; Lockington, David

    2013-04-01

    Coastal wetlands provide a wide variety of important ecosystem services but continue to suffer disturbance, degradation and deforestation. Sediment bacteria are responsible for major nutrient transformation and recycling in these ecosystems. Insight into microbial community composition and the factors that determine them may improve our understanding of biogeochemical processes, food web dynamics, biodegradation processes and, thus, help to develop the management strategies for preserving the ecosystem health and services. Characterizing shifts in community taxa along environmental gradients has been shown to provide a useful tool for determining the major drivers affecting community structure and function. North Stradbroke Island (NSI) in Southern Queensland presents considerable habitat diversity including variety of groundwater dependent ecosystems such as lakes, swamps, sedge-like salt marshes and mangroves. Ecological responses of continuous groundwater extraction for municipal purposes and sand mining operations on NSI are still need to be assessed in order to protect its unique environment. Changes in coastal hydrology due to either climate change or human activity may directly affect microbial populations and, thus, biogeochemical cycles of nutrients. These may result in altering/losing some ecosystem services provided by coastal wetlands. In this study we examine microbial diversity and determine environmental controls on bacterial community structure along a natural transition from freshwater forested wetland (melaleuca woodland), sedge-like salt marsh and into mangroves located at NSI. The study area is characterized by significant groundwater flow, nutrient limitation and sharp transition from one ecosystem type to another. Sediment cores (0-5 cm and 20-25 cm depth) were collected from three representative sites of each zone (mangroves - salt marsh - freshwater wetland) along the salinity gradient in August 2012. Subsamples were set aside for use in

  13. Coastal vegetation invasion increases greenhouse gas emission from wetland soils but also increases soil carbon accumulation

    International Nuclear Information System (INIS)

    Chen, Yaping; Chen, Guangcheng; Ye, Yong

    2015-01-01

    Soil properties and soil–atmosphere fluxes of CO 2 , CH 4 and N 2 O from four coastal wetlands were studied throughout the year, namely, native Kandelia obovata mangrove forest vs. exotic Sonneratia apetala mangrove forest, and native Cyperus malaccensis salt marsh vs. exotic Spartina alterniflora salt marsh. Soils of the four wetlands were all net sources of greenhouse gases while Sonneratia forest contributed the most with a total soil–atmosphere CO 2 -equivalent flux of 137.27 mg CO 2 m −2 h −1 , which is 69.23%, 99.75% and 44.56% higher than that of Kandelia, Cyperus and Spartina, respectively. The high underground biomass and distinctive root structure of Sonneratia might be responsible for its high greenhouse gas emission from the soil. Soils in Spartina marsh emitted the second largest amount of total greenhouse gases but it ranked first in emitting trace greenhouse gases. Annual average CH 4 and N 2 O fluxes from Spartina soil were 13.77 and 1.14 μmol m −2 h −1 , respectively, which are 2.08 and 1.46 times that of Kandelia, 1.03 and 1.15 times of Sonneratia, and 1.74 and 1.02 times of Cyperus, respectively. Spartina has longer growing season and higher productivity than native marshes which might increase greenhouse gas emission in cold seasons. Exotic wetland soils had higher carbon stock as compared to their respective native counterparts but their carbon stocks were offset by a larger proportion because of their higher greenhouse gas emissions. Annual total soil–atmosphere fluxes of greenhouse gases reduced soil carbon burial benefits by 8.1%, 9.5%, 6.4% and 7.2% for Kandelia, Sonneratia, Cyperus and Spartina, respectively, which narrowed down the gaps in net soil carbon stock between native and exotic wetlands. The results indicated that the invasion of exotic wetland plants might convert local coastal soils into a considerable atmospheric source of greenhouse gases although they at the same time increase soil carbon accumulation

  14. Coastal vegetation invasion increases greenhouse gas emission from wetland soils but also increases soil carbon accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yaping [Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen 361102, Fujian (China); Chen, Guangcheng [Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, Fujian (China); Ye, Yong, E-mail: yeyong.xmu@gmail.com [Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen 361102, Fujian (China)

    2015-09-01

    Soil properties and soil–atmosphere fluxes of CO{sub 2}, CH{sub 4} and N{sub 2}O from four coastal wetlands were studied throughout the year, namely, native Kandelia obovata mangrove forest vs. exotic Sonneratia apetala mangrove forest, and native Cyperus malaccensis salt marsh vs. exotic Spartina alterniflora salt marsh. Soils of the four wetlands were all net sources of greenhouse gases while Sonneratia forest contributed the most with a total soil–atmosphere CO{sub 2}-equivalent flux of 137.27 mg CO{sub 2} m{sup −2} h{sup −1}, which is 69.23%, 99.75% and 44.56% higher than that of Kandelia, Cyperus and Spartina, respectively. The high underground biomass and distinctive root structure of Sonneratia might be responsible for its high greenhouse gas emission from the soil. Soils in Spartina marsh emitted the second largest amount of total greenhouse gases but it ranked first in emitting trace greenhouse gases. Annual average CH{sub 4} and N{sub 2}O fluxes from Spartina soil were 13.77 and 1.14 μmol m{sup −2} h{sup −1}, respectively, which are 2.08 and 1.46 times that of Kandelia, 1.03 and 1.15 times of Sonneratia, and 1.74 and 1.02 times of Cyperus, respectively. Spartina has longer growing season and higher productivity than native marshes which might increase greenhouse gas emission in cold seasons. Exotic wetland soils had higher carbon stock as compared to their respective native counterparts but their carbon stocks were offset by a larger proportion because of their higher greenhouse gas emissions. Annual total soil–atmosphere fluxes of greenhouse gases reduced soil carbon burial benefits by 8.1%, 9.5%, 6.4% and 7.2% for Kandelia, Sonneratia, Cyperus and Spartina, respectively, which narrowed down the gaps in net soil carbon stock between native and exotic wetlands. The results indicated that the invasion of exotic wetland plants might convert local coastal soils into a considerable atmospheric source of greenhouse gases although they at the

  15. A computer model to forecast wetland vegetation changes resulting from restoration and protection in coastal Louisiana

    Science.gov (United States)

    Visser, Jenneke M.; Duke-Sylvester, Scott M.; Carter, Jacoby; Broussard, Whitney P.

    2013-01-01

    The coastal wetlands of Louisiana are a unique ecosystem that supports a diversity of wildlife as well as a diverse community of commercial interests of both local and national importance. The state of Louisiana has established a 5-year cycle of scientific investigation to provide up-to-date information to guide future legislation and regulation aimed at preserving this critical ecosystem. Here we report on a model that projects changes in plant community distribution and composition in response to environmental conditions. This model is linked to a suite of other models and requires input from those that simulate the hydrology and morphology of coastal Louisiana. Collectively, these models are used to assess how alternative management plans may affect the wetland ecosystem through explicit spatial modeling of the physical and biological processes affected by proposed modifications to the ecosystem. We have also taken the opportunity to advance the state-of-the-art in wetland plant community modeling by using a model that is more species-based in its description of plant communities instead of one based on aggregated community types such as brackish marsh and saline marsh. The resulting model provides an increased level of ecological detail about how wetland communities are expected to respond. In addition, the output from this model provides critical inputs for estimating the effects of management on higher trophic level species though a more complete description of the shifts in habitat.

  16. Are Predators Limiting Zebra Mussel Colonization of Unionid Mussels in Great Lake Coastal Wetlands?

    Science.gov (United States)

    de Szalay, F. A.; Bowers, R.

    2005-05-01

    Although many native mollusc populations have been eliminated in the Laurentian Great Lakes by the exotic zebra mussel, recent surveys have found abundant unionid (Bivalvia: Unionidae) populations in some coastal wetlands. Unionid burrowing in soft sediments and predation by fish have been shown to reduce numbers of attached zebra mussels, and we tested these factors in a Lake Erie coastal wetland. In 2002, we held live unionids (Leptodea fragilis, Quadrula quadrula) and Pyganodon grandis shells in exclosures with wire mesh bottoms that were buried to sediment depths of either 5, 10, or 20 cm. After 2 months, numbers of attached dreissenids on unionids were significantly higher inside all exclosure treatments than outside exclosures. This indicated that either unionid burrowing was prevented in all sediment depth treatments or molluscivores were excluded by exclosures. In 2004, we measured dreissenid colonization on Q. quadrula and PVC plates in bottomless exclosures with different mesh sizes. After 6 months, dreissenid numbers on PVC plates and on Q. quadrula in 2.5 cm X 2.5 cm and 5 cm X 10 cm mesh exclosures were significantly higher than in open exclosures. These data suggest that molluscivores are important in limiting dreissenids in Great Lake coastal wetlands.

  17. Multi-temporal RADARSAT-1 and ERS backscattering signatures of coastal wetlands in southeastern Louisiana

    Science.gov (United States)

    Kwoun, Oh-Ig; Lu, Z.

    2009-01-01

    Using multi-temporal European Remote-sensing Satellites (ERS-1/-2) and Canadian Radar Satellite (RADARSAT-1) synthetic aperture radar (SAR) data over the Louisiana coastal zone, we characterize seasonal variations of radar backscat-tering according to vegetation type. Our main findings are as follows. First, ERS-1/-2 and RADARSAT-1 require careful radiometric calibration to perform multi-temporal backscattering analysis for wetland mapping. We use SAR backscattering signals from cities for the relative calibration. Second, using seasonally averaged backscattering coefficients from ERS-1/-2 and RADARSAT-1, we can differentiate most forests (bottomland and swamp forests) and marshes (freshwater, intermediate, brackish, and saline marshes) in coastal wetlands. The student t-test results support the usefulness of season-averaged backscatter data for classification. Third, combining SAR backscattering coefficients and an optical-sensor-based normalized difference vegetation index can provide further insight into vegetation type and enhance the separation between forests and marshes. Our study demonstrates that SAR can provide necessary information to characterize coastal wetlands and monitor their changes.

  18. Irrigation and avifaunal change in coastal Northwest Mexico: has irrigated habit attracted threatened migratory species?

    Science.gov (United States)

    Grason, Emily; Navarro-Sigüenza, Adolfo G.

    2015-01-01

    Irrigation in desert ecosystems can either reduce or increase species diversity. Groundwater pumping often lowers water tables and reduces natural wetlands, whereas canal irrigation often creates mesic habitat, resulting in great increases in avian diversity from irrigation. Here we compare a dataset of potential natural vegetation to recent datasets from areal and satellite imagery to show that 60% of the land in the coastal plain of southern Sonora and northern Sinaloa lying below 200 m elevation has been converted by irrigation to more mesic habitats. We then use the record of bird specimens in the world’s museums from this same region of Mexico to examine the avian community before and after the development of extensive irrigation. In general these museum records show an increase in the abundance and diversity of breeding birds associated with mesic habitats. Although thorn forest birds have likely decreased in total numbers, most are common enough in the remaining thorn forest that collection records did not indicate their probable decline. Four migrants having most of their breeding ranges in the US or Canada, Yellow-billed Cuckoo, Cliff Swallow, Bell’s Vireo, and Orchard Oriole, apparently have increased dramatically as breeders in irrigated habitats of NW Mexico. Because these species have decreased or even largely disappeared as breeding birds in parts of the US or Canada, further research should assess whether their increases in new mesic habitats of NW Mexico are linked to their declines as breeding birds in Canada and the US For Bell’s Vireo recent specimens from Sinaloa suggest its new breeding population in NW Mexico may be composed partly of the endangered Least Bell’s Vireo. PMID:26312181

  19. Rising tides, rising gates: The complex ecogeomorphic response of coastal wetlands to sea-level rise and human interventions

    Science.gov (United States)

    Sandi, Steven G.; Rodríguez, José F.; Saintilan, Neil; Riccardi, Gerardo; Saco, Patricia M.

    2018-04-01

    Coastal wetlands are vulnerable to submergence due to sea-level rise, as shown by predictions of up to 80% of global wetland loss by the end of the century. Coastal wetlands with mixed mangrove-saltmarsh vegetation are particularly vulnerable because sea-level rise can promote mangrove encroachment on saltmarsh, reducing overall wetland biodiversity. Here we use an ecogeomorphic framework that incorporates hydrodynamic effects, mangrove-saltmarsh dynamics, and soil accretion processes to assess the effects of control structures on wetland evolution. Migration and accretion patterns of mangrove and saltmarsh are heavily dependent on topography and control structures. We find that current management practices that incorporate a fixed gate for the control of mangrove encroachment are useful initially, but soon become ineffective due to sea-level rise. Raising the gate, to counteract the effects of sea level rise and promote suitable hydrodynamic conditions, excludes mangrove and maintains saltmarsh over the entire simulation period of 100 years

  20. Assessing the recovery of coastal wetlands from oil spills

    International Nuclear Information System (INIS)

    Mendelssohn, I.A.; Hester, M.W.; Hill, J.M.

    1993-01-01

    The impact of oil spills on coastal environments and the ability of these systems to exhibit long-term recovery has received increased attention in recent years. Although oil spills can have significant short-term impacts on coastal marshes, the long-term effects and eventual recovery are not well documented. Estuarine marshes have sometimes been reported to exhibit slow recovery after oil spills, whereas in other instances they appear to have great resiliency, with complete recovery after one or two years. To document and understand this phenomenon better, we have investigated the long-term recovery of a south Louisiana estuarine marsh exposed to an accidental spill of crude oil. Although a pipeline rupture releasing Louisiana crude oil caused the near complete mortality of a brackish marsh dominated by Spartina patens and S. alterniflora, this marsh completely recovered four years after the spill with no differences in plant species cover between oiled and reference marshes. Remotely sensed imagery of the study site confirmed the relatively rapid recovery demonstrated by the ground truth data. Louisiana's coastal marshes are naturally experiencing rapid rates of deterioration. Land loss rates, determined from aerial imagery, at the spill site and adjacent reference areas before and after the spill demonstrated that the long-term loss rates were not affected by the spill event

  1. Fish community structure and dynamics in a coastal hypersaline lagoon: Rio Lagartos, Yucatan, Mexico

    Science.gov (United States)

    Vega-Cendejas, Ma. Eugenia; Hernández de Santillana, Mireya

    2004-06-01

    Rio Lagartos, a tropical coastal lagoon in northern Yucatan Peninsula of Mexico, is characterized by high salinity during most of the year (55 psu annual average). Even though the area has been designated as a wetland of international importance because of its great biodiversity, fish species composition and distribution are unknown. To determine whether the salinity gradient was influencing fish assemblages or not, fish populations were sampled seasonally by seine and trawl from 1992 to 1993 and bimonthly during 1997. We identified 81 fish species, eight of which accounted for 53.1% considering the Importance Value Index ( Floridichthys polyommus, Sphoeroides testudineus, Eucinostomus argenteus, Eucinostomus gula, Fundulus majalis, Strongylura notata, Cyprinodon artifrons and Elops saurus). Species richness and density declined from the mouth to the inner zone where extreme salinity conditions are prominent (>80) and competitive interactions decreased. However, in Coloradas basin (53 average sanity) and in the inlet of the lagoon, the highest fish density and number of species were observed. Greater habitat heterogeneity and fish immigration were considered as the best explanation. Multivariate analysis found three zones distinguished by fish occurrence, abundance and distribution. Ichthyofaunal spatial differences were attributed to selective recruitment from the Gulf of Mexico due to salinity gradient and to changing climatic periods. Estuarine and euryhaline marine species are abundant, with estuarine dependent ones entering the system according to environmental preferences. This knowledge will contribute to the management of the Special Biosphere Reserve through baseline data to evaluate environmental and anthropogenic changes.

  2. The contrasting effects of nutrient enrichment on growth, biomass allocation and decomposition of plant tissue in coastal wetlands

    NARCIS (Netherlands)

    Hayes, Matthew A.; Jesse, Amber; Tabet, Basam; Reef, Ruth; Keuskamp, Joost A.; Lovelock, Catherine E.

    2017-01-01

    Eutrophication of coastal waters can have consequences for the growth, function and soil processes of coastal wetlands. Our aims were to assess how nutrient enrichment affects growth, biomass allocation and decomposition of plant tissues of a common and widespread mangrove, Avicennia marina, and how

  3. Incorporating future change into current conservation planning: Evaluating tidal saline wetland migration along the U.S. Gulf of Mexico coast under alternative sea-level rise and urbanization scenarios

    Science.gov (United States)

    Enwright, Nicholas M.; Griffith, Kereen T.; Osland, Michael J.

    2015-11-02

    In this study, the U.S. Geological Survey, in cooperation with the U.S. Fish and Wildlife Service, quantified the potential for landward migration of tidal saline wetlands along the U.S. Gulf of Mexico coast under alternative future sea-level rise and urbanization scenarios. Our analyses focused exclusively on tidal saline wetlands (that is, mangrove forests, salt marshes, and salt flats), and we combined these diverse tidal saline wetland ecosystems into a single grouping, “tidal saline wetland.” Collectively, our approach and findings can provide useful information for scientists and environmental planners working to develop future-focused adaptation strategies for conserving coastal landscapes and the ecosystem goods and services provided by tidal saline wetlands. The primary product of this work is a public dataset that identifies locations where landward migration of tidal saline wetlands is expected to occur under alternative future sea-level rise and urbanization scenarios. In addition to identifying areas where landward migration of tidal saline wetlands is possible because of the absence of barriers, these data also identify locations where landward migration of these wetlands could be prevented by barriers associated with current urbanization, future urbanization, and levees.

  4. High-resolution mapping of wetland vegetation biomass and distribution with L-band radar in southeastern coastal Louisiana

    Science.gov (United States)

    Thomas, N. M.; Simard, M.; Byrd, K. B.; Windham-Myers, L.; Castaneda, E.; Twilley, R.; Bevington, A. E.; Christensen, A.

    2017-12-01

    Louisiana coastal wetlands account for approximately one third (37%) of the estuarine wetland vegetation in the conterminous United States, yet the spatial distribution of their extent and aboveground biomass (AGB) is not well defined. This knowledge is critical for the accurate completion of national greenhouse gas (GHG) inventories. We generated high-resolution baselines maps of wetland vegetation extent and biomass at the Atchafalaya and Terrebonne basins in coastal Louisiana using a multi-sensor approach. Optical satellite data was used within an object-oriented machine learning approach to classify the structure of wetland vegetation types, offering increased detail over currently available land cover maps that do not distinguish between wetland vegetation types nor account for non-permanent seasonal changes in extent. We mapped 1871 km2 of wetlands during a period of peak biomass in September 2015 comprised of flooded forested wetlands and leaf, grass and emergent herbaceous marshes. The distribution of aboveground biomass (AGB) was mapped using JPL L-band Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR). Relationships between time-series radar imagery and field data collected in May 2015 and September 2016 were derived to estimate AGB at the Wax Lake and Atchafalaya deltas. Differences in seasonal biomass estimates reflect the increased AGB in September over May, concurrent with periods of peak biomass and the onset of the vegetation growing season, respectively. This method provides a tractable means of mapping and monitoring biomass of wetland vegetation types with L-band radar, in a region threatened with wetland loss under projections of increasing sea-level rise and terrestrial subsidence. Through this, we demonstrate a method that is able to satisfy the IPCC 2013 Wetlands Supplement requirement for Tier 2/Tier 3 reporting of coastal wetland GHG inventories.

  5. Potential increase in coastal wetland vulnerability to sea-level rise suggested by considering hydrodynamic attenuation effects

    Science.gov (United States)

    Rodríguez, José F.; Saco, Patricia M.; Sandi, Steven; Saintilan, Neil; Riccardi, Gerardo

    2017-07-01

    The future of coastal wetlands and their ecological value depend on their capacity to adapt to the interacting effects of human impacts and sea-level rise. Even though extensive wetland loss due to submergence is a possible scenario, its magnitude is highly uncertain due to limited understanding of hydrodynamic and bio-geomorphic interactions over time. In particular, the effect of man-made drainage modifications on hydrodynamic attenuation and consequent wetland evolution is poorly understood. Predictions are further complicated by the presence of a number of vegetation types that change over time and also contribute to flow attenuation. Here, we show that flow attenuation affects wetland vegetation by modifying its wetting-drying regime and inundation depth, increasing its vulnerability to sea-level rise. Our simulations for an Australian subtropical wetland predict much faster wetland loss than commonly used models that do not consider flow attenuation.

  6. Building Coastal Resilience to sea-level rise and storm hazards: supporting decisions in the NE USA, Gulf of Mexico, and eastern Caribbean

    Science.gov (United States)

    Shepard, C.; Beck, M. W.; Gilmer, B.; Ferdana, Z.; Raber, G.; Agostini, V.; Whelchel, A.; Stone, J.

    2012-12-01

    Coastal communities are increasingly vulnerable to coastal hazards including storm surge and sea level rise. We describe the use of Coastal Resilience, an approach to help support decisions to reduce socio-economic and ecological vulnerability to coastal hazards. We provide examples of this work from towns and cities around Long Island Sound (NY, CT) and the Gulf of Mexico (FL, AL, MS, LA, TX) in the USA and from the Eastern Caribbean (Grenada, St. Vincent and the Grenadines). All of these shores are densely populated and have significant coastal development only centimetres above the sea. This makes people and property very vulnerable and threatens coastal wetlands (marsh, mangrove) and reefs (oyster, coral) that provide habitat and natural buffers to storms while providing other ecosystem services. We describe this work specifically and then offer broader perspectives and recommendations for using ecological habitats to reduce vulnerability to coastal hazards. The Nature Conservancy's Coastal Resilience approach is driven by extensive community engagement and uses spatial information on storm surge, sea level rise, ecological and socio-economic variables to identify options for reducing the vulnerability of human and natural communities to coastal hazards (http://www.coastalresilience.org). We have worked with local communities to map current and future coastal hazards and to identify the vulnerable natural resources and human communities. Communities are able to visualize potential hazard impacts and identify options to reduce them within their existing planning and regulatory frameworks.

  7. Effects of salinity and flooding on post-hurricane regeneration potential in coastal wetland vegetation.

    Science.gov (United States)

    Middleton, Beth A

    2016-08-01

    The nature of regeneration dynamics after hurricane flooding and salinity intrusion may play an important role in shaping coastal vegetation patterns. The regeneration potentials of coastal species, types and gradients (wetland types from seaward to landward) were studied on the Delmarva Peninsula after Hurricane Sandy using seed bank assays to examine responses to various water regimes (unflooded and flooded to 8 cm) and salinity levels (0, 1, and 5 ppt). Seed bank responses to treatments were compared using a generalized linear models approach. Species relationships to treatment and geographical variables were explored using nonmetric multidimensional scaling. Flooding and salinity treatments affected species richness even at low salinity levels (1 and 5 ppt). Maritime forest was especially intolerant of salinity intrusion so that species richness was much higher in unflooded and low salinity conditions, despite the proximity of maritime forest to saltmarsh along the coastal gradient. Other vegetation types were also affected, with potential regeneration of these species affected in various ways by flooding and salinity, suggesting relationships to post-hurricane environment and geographic position. Seed germination and subsequent seedling growth in coastal wetlands may in some cases be affected by salinity intrusion events even at low salinity levels (1 and 5 ppt). These results indicate that the potential is great for hurricanes to shift vegetation type in sensitive wetland types (e.g., maritime forest) if post-hurricane environments do not support the regeneration of extent vegetation. This article is a U.S. Government work and is in the public domain in the USA. © Botanical Society of America (outside the USA) 2016.

  8. Simulation of integrated surface-water/ground-water flow and salinity for a coastal wetland and adjacent estuary

    Science.gov (United States)

    Langevin, C.; Swain, E.; Wolfert, M.

    2005-01-01

    The SWIFT2D surface-water flow and transport code, which solves the St Venant equations in two dimensions, was coupled with the SEAWAT variable-density ground-water code to represent hydrologic processes in coastal wetlands and adjacent estuaries. A sequentially coupled time-lagged approach was implemented, based on a variable-density form of Darcy's Law, to couple the surface and subsurface systems. The integrated code also represents the advective transport of salt mass between the surface and subsurface. The integrated code was applied to the southern Everglades of Florida to quantify flow and salinity patterns and to evaluate effects of hydrologic processes. Model results confirm several important observations about the coastal wetland: (1) the coastal embankment separating the wetland from the estuary is overtopped only during tropical storms, (2) leakage between the surface and subsurface is locally important in the wetland, but submarine ground-water discharge does not contribute large quantities of freshwater to the estuary, and (3) coastal wetland salinities increase to near seawater values during the dry season, and the wetland flushes each year with the onset of the wet season. ?? 2005 Elsevier B.V. All rights reserved.

  9. ALL THAT "PHRAG": BRINGING ENGINEERING, WETLAND ECOLOGY, ENVIRONMENTAL SCIENCE, AND LANDSCAPE ECOLOGY TO BEAR ON THE QUESTION OF COMMON REED IN GREAT LAKES COASTAL WETLANDS

    Science.gov (United States)

    Coastal wetlands are among the most fragmented and disturbed ecosystems and the Great Lakes are no exception. One possible result is the observed increase in the presence and dominance of invasive and other opportunistic plant species, such as the common reed (Phragmites australi...

  10. Linking the historic 2011 Mississippi River flood to coastal wetland sedimentation

    Science.gov (United States)

    Falcini, Federico; Khan, Nicole S.; Macelloni, Leonardo; Horton, Benjamin P.; Lutken, Carol B.; McKee, Karen L.; Santoleri, Rosalia; Colella, Simone; Li, Chunyan; Volpe, Gianluca; D’Emidio, Marco; Salusti, Alessandro; Jerolmack, Douglas J.

    2012-01-01

    Wetlands in the Mississippi River deltaic plain are deteriorating in part because levees and control structures starve them of sediment. In Spring of 2011 a record-breaking flood brought discharge on the lower Mississippi River to dangerous levels, forcing managers to divert up to 3500 m3/s-1 of water to the Atchafalaya River Basin. Here we quantify differences between the Mississippi and Atchafalaya River inundation and sediment-plume patterns using field-calibrated satellite data, and assess the impact these outflows had on wetland sedimentation. We characterize hydrodynamics and suspended sediment patterns of the Mississippi River plume using in-situ data collected during the historic flood. We show that the focused, high-momentum jet from the leveed Mississippi delivered sediment far offshore. In contrast, the plume from the Atchafalaya was more diffuse; diverted water inundated a large area; and sediment was trapped within the coastal current. Maximum sedimentation (up to several centimetres) occurred in the Atchafalaya Basin despite the larger sediment load carried by the Mississippi. Minimum accumulation occurred along the shoreline between these river sources. Our findings provide a mechanistic link between river-mouth dynamics and wetland sedimentation patterns that is relevant for plans to restore deltaic wetlands using artificial diversions.

  11. An Initial Assessment of the Economic Value of Coastal and Freshwater Wetlands in West Asia

    Directory of Open Access Journals (Sweden)

    Florian V. Eppink

    2014-06-01

    Full Text Available Many countries in West Asia, defined in this study as the Arabic-speaking countries of the Arabian Peninsula plus Turkey and Iran, have enacted environmental conservation laws but regional underlying drivers of environment change, such as rising incomes and fast-growing populations, continue to put pressure on remaining wetlands. This paper aims to inform conservation efforts by presenting the first regional assessment of the economic value of coastal and freshwater wetlands in West Asia. Using scenario analysis we find that, dependent on the discount rate used, the present value of the regional economic loss of not protecting wetlands by 2050 is between US dollar 2.3 billion and US dollar 7.2 billion (expressed in 2007 US dollars. The method used for this assessment, however, is not suitable for expressing national realities adequately. We therefore suggest that detailed localized studies are conducted to improve insight into the drivers and the social and economic effects of wetland loss in West Asia.

  12. 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.

  13. 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.

  14. Mercury in the atmospheric and coastal environments of Mexico.

    Science.gov (United States)

    Ruelas-Inzunza, Jorge; Delgado-Alvarez, Carolina; Frías-Espericueta, Martín; Páez-Osuna, Federico

    2013-01-01

    In Mexico, published studies relating to the occurrence of Hg in the environment are limited. Among the main sources of Hg in Mexico are mining and refining of Auand Hg, chloralkali plants, Cu smelting, residential combustion of wood, carbo electric plants, and oil refineries. Hg levels are highly variable in the atmospheric compartment because of the atmospheric dynamics and ongoing metal exchange with the terrestrial surface. In atmospheric studies, Hg levels are usually reported as total gaseous Hg (TGM). In Mexico, TGM values ranged from 1.32 ng m-3 in Hidalgo state (a rural agricultural area) to 71.82 ng m-3 in Zacatecas state (an area where brick manufacturers use mining wastes as a raw material).Published information on mercury levels in the coastal environment comprise 21 studies, representing 21 areas, in which sediments constituted the substrate that was analyzed for Hg. In addition, water samples were analyzed for Hg in nine studies.Few studies exist on Hg levels in the Caribbean and in the southwest of the country where tourism is rapidly increasing. Hence, there is a need for establishing baseline levels of mercury in these increasingly visited areas. In regions where studies have been undertaken, Hg levels in sediments were highly variable. Variations in Hg sediment levels mainly result from geological factors and the varying degree of anthropogenic impacts in the studied areas. In areas that still have pristine or nearly pristine environments (e.g., coast, Baja California, Todos Santos Bay, and La Paz lagoon), sediment Hg levels ranged from Mexico, it is clear that Hg fluxes to sediments have increased from2- to 15-fold in recent years. Since the 1940s, historical increases of Hg fluxes have resulted from higher agricultural waste releases and exhaust from the thermo electric plants. The levels of Hg in water reveal a moderate to elevated contamination of some Mexican coastal sites. In Urias lagoon (NW Mexico), moderate to high levels were found in

  15. Effects of Spartina alterniflora invasion on biogenic elements in a subtropical coastal mangrove wetland.

    Science.gov (United States)

    Yu, Xiaoqing; Yang, Jun; Liu, Lemian; Tian, Yuan; Yu, Zheng

    2015-02-01

    The invasion by exotic cordgrass (Spartina alterniflora) has become one of the most serious and challenging environmental and ecological problems in coastal China because it can have adverse effects on local native species, thereby changing ecosystem processes, functions, and services. In this study, 300 surface sediments were collected from 15 stations in the Jiulong River Estuary, southeast China, across four different seasons, in order to reveal the spatiotemporal variability of biogenic elements and their influencing factors in the subtropical coastal mangrove wetland. The biogenic elements including carbon, nitrogen, and sulfur (C, N, and S) were determined by an element analyzer, while the phosphorus (P) was determined by a flow injection analyzer. The concentrations of biogenic elements showed no significant differences among four seasons except total phosphorus (TP); however, our ANOVA analyses revealed a distinct spatial pattern which was closely related with the vegetation type and tidal level. Values of total carbon (TC) and total nitrogen (TN) in the surface sediment of mangrove vegetation zones were higher than those in the cordgrass and mudflat zones. The concentrations of TC, TN, TP, and total sulfur (TS) in the high tidal zones were higher than those in the middle and low tidal zones. Redundancy analysis (RDA) revealed that tidal level, vegetation type, and season had some significant influence on the distribution of biogenic elements in the Jiulong River Estuary, by explaining 18.2, 7.7, and 4.9 % of total variation in the four biogenic elements, respectively. In conclusion, S. alterniflora invasion had substantial effects on the distributions of biogenic elements in the subtropical coastal wetland. If regional changes in the Jiulong River Estuary are to persist and much of the mangrove vegetation was to be replaced by cordgrass, there would be significant decreases on the overall storage of C and N in this coastal zone. Therefore, the native

  16. Blue Carbon Sequestration in Florida Coastal Wetlands - Response to Recent Climate Change and Holocene Climate Variability

    Science.gov (United States)

    Vaughn, D.; Bianchi, T. S.; Osborne, T.; Shields, M. R.; Kenney, W.

    2017-12-01

    Intertidal forests and salt marshes represent a major component of Florida's coasts and are essential to the health and integrity of coastal Florida's ecological and economic systems. In addition, coastal wetlands have been recognized as highly efficient carbon sinks with their ability to store carbon on time scales from centuries to millennia. Although losses of salt marshes, mangroves, and seagrass beds through both natural and anthropogenic forces are threatening their ability to act as carbon sinks globally, the poleward encroachment of mangroves into higher latitude salt marshes may lead to regional increases in carbon sequestration as mangroves store more carbon than salt marshes. For Florida, this encroachment of mangroves into salt marshes is prominent along the northern coasts where fewer freeze events have coincided with an increase in mangrove extent over the past several decades. Soil cores collected from a northeastern Florida wetland will allow us to determine whether the recent poleward encroachment of mangroves into northern Florida salt marshes has led to an increase in belowground carbon storage. The soil cores, which are approximately two to three meters in length, will also provide the first known record of carbon storage in a northern Florida wetland during the Holocene. Initial results from the top 40 cm, which represents 100 years based on dating of other northern Florida wetland cores, suggest more carbon is currently being stored within the transition between marsh and mangrove than in areas currently covered by salt marsh vegetation or mangroves. The transitional zone also has a much larger loss of carbon within the top 40 cm compared to the mangrove and marsh cores. Lignin-based degradation indices along with other biomarker data and 210Pb/137Cs ages will be presented to demonstrate how much of this loss of carbon may be related to degradation and how much may be related to changes in carbon sources.

  17. Physiological Responses of Kosteletzkya virginica to Coastal Wetland Soil

    Directory of Open Access Journals (Sweden)

    Hongyan Wang

    2015-01-01

    Full Text Available Effects of salinity on growth and physiological indices of Kosteletzkya virginica seedlings were studied. Plant height, fresh weight (FW, dry weight (DW, and net photosynthetic rate (Pn increased at 100 mM NaCl and slightly declined at 200 mM, but higher salinity induced a significant reduction. Chlorophyll content, stomatal conductance (Gs, intercellular CO2 concentration (Ci, and transpiration rate (E were not affected under moderate salinities, while markedly decreased at severe salinities except for the increased Ci at 400 mM NaCl. Furthermore, no significant differences of Fv/Fm and ΦPSII were found at lower than 200 mM NaCl, whereas higher salinity caused the declines of Fv/Fm, ΦPSII, and qP similar to Pn, accompanied with higher NPQ. Besides, salt stress reduced the leaf RWC, but caused the accumulation of proline to alleviate osmotic pressure. The increased activities of antioxidant enzymes maintained the normal levels of MDA and relative membrane permeability. To sum up, Kosteletzkya virginica seedlings have good salt tolerance and this may be partly attributed to its osmotic regulation and antioxidant capacity which help to maintain water balance and normal ROS level to ensure the efficient photosynthesis. These results provided important implications for Kosteletzkya virginica acting as a promising multiuse species for reclaiming coastal soil.

  18. The potential accumulation of polycyclic aromatic hydrocarbons in phytoplankton and bivalves in Can Gio coastal wetland, Vietnam.

    Science.gov (United States)

    Thuy, Hoang Thi Thanh; Loan, Tu Thi Cam; Phuong, Trinh Hong

    2018-05-12

    Polycyclic aromatic hydrocarbons (PAHs) are one of the most important classes of anthropogenic persistent organic contaminants in the marine environment. This review discusses a whole range of findings that address various aspects of the bioaccumulation of PAHs in two common marine biota (phytoplankton and bivalves) globally and especially for Can Gio coastal wetland, Vietnam. The published information and collected data on the bioconcentration and accumulation mechanisms of PAHs as well as implications for Can Gio coastal wetland are compiled for phytoplankton and bivalves. PAHs are still released to Can Gio coastal environments from various sources and then transported to coastal environments through various physical processes; they may enter marine food chains and be highly accumulated in phytoplankton and bivalves. Thus, PAHs' bioaccumulation should be considered as one important criterion to assess the water's quality, directly linked to human health due to seafood consumption. Ecologically, Can Gio coastal wetland plays an important role to the South Vietnam key economic zone. However, it is also an area of potential PAHs inputs. With the abundant phytoplankton and bivalves in Can Gio coastal wetland, the PAHs bioaccumulation in these biota is inevitably detected. Thus, further study on the bioavailability of these contaminants is urgently needed in order to mitigate their negative effects and protect the ecosystems.

  19. Hurricane Matthew's Effects on Wetland Sources of Organic Matter to North Carolina Coastal Waters.

    Science.gov (United States)

    Rudolph, J. C.; Osburn, C. L.; Paerl, H. W.; Hounshell, A.

    2017-12-01

    Increased frequency and intensity of storm events such as tropical cyclones will have a major impact on estuarine and coastal biogeochemical cycling. Here, we determined the sources of dissolved and particulate organic matter (DOM and POM) as part of a larger study to quantify the short-term (several months) response of carbon and nitrogen cycling in the Neuse River Estuary-Pamlico Sound (NRE-PS) ecosystem to floodwaters associated with Hurricane Matthew. Sampling was conducted weekly in both the NRE-PS (October 2016 to January 2017), the Neuse River (NR) (October to December 2016) and in freshwater wetlands of the Neuse River above head of tide in March 2017. Specific ultraviolet (UV) absorbance at 254 nm (SUVA254) and stable carbon isotope ratios (δ13C-DOC) were used to determine the sources of DOM and POM transported to the NRE-PS in post-hurricane floodwaters. For DOM, SUVA254 values increased from 3.23 ±0.52 mg C L-1 m-1 in the NR to 4.14±0.52 mg C L-1 m-1 in the NRE and then declined to 3.63±0.32 mg C L-1 m-1 in PS. Combined with depleted δ13C-DOC values (-26 to -32‰) and elevated C:N values in the estuary and sound, these results confirm continued loading of fresh terrestrial organic matter into NRE-PS weeks after the storm. For POM, δ13C-POC and C:N ratio results likewise indicated a terrestrial source in floodwaters. SUVA254 values >3.5 mg C L-1 m-1 coupled with the depleted δ13C values and large C:N values were consistent with DOM primarily sourced from wetlands (e.g., wetland SUVA254 = 3.77±0.52 mg C L-1 m-1 in March 2017). We hypothesize that floodwaters connected riverine wetlands to the main channel of the NR, exporting DOM and POM into the NRE-PS. Our results indicate that upstream wetlands play a central and potentially significant role in organic matter enrichment and metabolism of estuarine and coastal waters, in light of increasing frequencies and intensities of tropical cyclones impacting coastal watersheds.

  20. Terrestrial laser scanning to quantify above-ground biomass of structurally complex coastal wetland vegetation

    Science.gov (United States)

    Owers, Christopher J.; Rogers, Kerrylee; Woodroffe, Colin D.

    2018-05-01

    Above-ground biomass represents a small yet significant contributor to carbon storage in coastal wetlands. Despite this, above-ground biomass is often poorly quantified, particularly in areas where vegetation structure is complex. Traditional methods for providing accurate estimates involve harvesting vegetation to develop mangrove allometric equations and quantify saltmarsh biomass in quadrats. However broad scale application of these methods may not capture structural variability in vegetation resulting in a loss of detail and estimates with considerable uncertainty. Terrestrial laser scanning (TLS) collects high resolution three-dimensional point clouds capable of providing detailed structural morphology of vegetation. This study demonstrates that TLS is a suitable non-destructive method for estimating biomass of structurally complex coastal wetland vegetation. We compare volumetric models, 3-D surface reconstruction and rasterised volume, and point cloud elevation histogram modelling techniques to estimate biomass. Our results show that current volumetric modelling approaches for estimating TLS-derived biomass are comparable to traditional mangrove allometrics and saltmarsh harvesting. However, volumetric modelling approaches oversimplify vegetation structure by under-utilising the large amount of structural information provided by the point cloud. The point cloud elevation histogram model presented in this study, as an alternative to volumetric modelling, utilises all of the information within the point cloud, as opposed to sub-sampling based on specific criteria. This method is simple but highly effective for both mangrove (r2 = 0.95) and saltmarsh (r2 > 0.92) vegetation. Our results provide evidence that application of TLS in coastal wetlands is an effective non-destructive method to accurately quantify biomass for structurally complex vegetation.

  1. AN ECOLOGICAL ASSESSMENT OF INVASIVE AND AGRESSIVE PLANT SPECIES IN COASTAL WETLANDS OF THE LAURENTIAN GREAT LAKES: A COMBINED FIELD BASED AND REMOTE SENSING APPROACH

    Science.gov (United States)

    The aquatic plant communities within coastal wetlands of the Laurentian Great Lakes are among the most biologically diverse and productive systems of the world. Coastal wetlands have been especially impacted by landscape conversion and have undergone a marked decline in plant com...

  2. Hydrologic and Vegetative Removal of Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii Surrogate Microspheres in Coastal Wetlands

    Science.gov (United States)

    Hogan, Jennifer N.; Daniels, Miles E.; Watson, Fred G.; Oates, Stori C.; Miller, Melissa A.; Conrad, Patricia A.; Shapiro, Karen; Hardin, Dane; Dominik, Clare; Melli, Ann; Jessup, David A.

    2013-01-01

    Constructed wetland systems are used to reduce pollutants and pathogens in wastewater effluent, but comparatively little is known about pathogen transport through natural wetland habitats. Fecal protozoans, including Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii, are waterborne pathogens of humans and animals, which are carried by surface waters from land-based sources into coastal waters. This study evaluated key factors of coastal wetlands for the reduction of protozoal parasites in surface waters using settling column and recirculating mesocosm tank experiments. Settling column experiments evaluated the effects of salinity, temperature, and water type (“pure” versus “environmental”) on the vertical settling velocities of C. parvum, G. lamblia, and T. gondii surrogates, with salinity and water type found to significantly affect settling of the parasites. The mesocosm tank experiments evaluated the effects of salinity, flow rate, and vegetation parameters on parasite and surrogate counts, with increased salinity and the presence of vegetation found to be significant factors for removal of parasites in a unidirectional transport wetland system. Overall, this study highlights the importance of water type, salinity, and vegetation parameters for pathogen transport within wetland systems, with implications for wetland management, restoration efforts, and coastal water quality. PMID:23315738

  3. Geoid determination in the coastal areas of the Gulf of Mexico

    Science.gov (United States)

    Song, HongZhi

    Coastal areas of the Gulf of Mexico are important for many reasons. This part of the United States provides vital coastal habitats for many marine species; the area has seen-ever increasing human settlement along the coast, ever increasing infrastructure for marine transportation of the nation's imports and exports through Gulf ports, and ever increasing recreational users of coastal resources. These important uses associated with the Gulf coast are subject to dynamic environmental and physical changes including: coastal erosion (Gulf-wide rates of 25 square miles per year), tropical storm surges, coastal subsidence, and global sea level rise. Coastal land subsidence is a major component of relative sea level rise along the coast of the Gulf of Mexico. These dynamic coastal changes should be evident in changes to the geoid along the coast. The geoid is the equipotential gravity surface of the earth, which the best fits the global mean sea level. The geoid is not only been seen as the most natural shape of the Earth, but also it serves as the reference surface for most of the height systems. By using satellites (GRACE mission) scientists have been able to measure the large scale geoid for the Earth. A small scale geoid model is required to monitor local events such as flooding, for example, flooding created by storm surges from hurricanes such as Katrina (2005), Rita (2005), and Ike (2008). The overall purpose of this study is to evaluate the accuracy of the local coastal geoid. The more precise geoid will enable to improve coastal flooding predictions, and will enable more cost effective and accurate measurement of coastal topography using global navigation satellite systems (GNSS). The main objective of this study is to devise mathematical models and computational methods to achieve the best possible precision for evaluation of the geoid in the coastal areas of the Gulf of Mexico. More specifically, the numerical objectives of this study are 1) to obtain a

  4. Validation and Comparison of a Model of the Effect of Sea-Level Rise on Coastal Wetlands.

    Science.gov (United States)

    Mogensen, Laura A; Rogers, Kerrylee

    2018-01-22

    Models are used to project coastal wetland distribution under future sea-level rise scenarios to assist decision-making. Model validation and comparison was used to investigate error and uncertainty in the Sea Level Affecting Marshes Model, a readily available model with minimal validation, particularly for wetlands beyond North America. Accurate parameterisation is required to improve the performance of the model, and indeed any spatial model. Consideration of tidal attenuation further enhances model performance, particularly for coastal wetlands located within estuaries along wave-dominated coastlines. The model does not simulate vegetation changes that are known to occur, particularly when sedimentation exceeds rates of sea-level rise resulting in shoreline progradation. Model performance was reasonable over decadal timescales, decreasing as the time-scale of retrospection increased due to compounding of errors. Comparison with other deterministic models showed reasonable agreement by 2100. However, given the uncertainty of the future and the unpredictable nature of coastal wetlands, it is difficult to ascertain which model could be realistic enough to meet its intended purpose. Model validation and comparison are useful for assessing model efficacy and parameterisation, and should be applied before application of any spatially explicit model of coastal wetland response to sea-level rise.

  5. Organic carbon isotope ratios of recent sediments from coastal lagoons of the Gulf of Mexico, Mexico

    International Nuclear Information System (INIS)

    Botello, A.V.; Mandelli, E.F.; Macko, S.; Parker, P.L.

    1980-01-01

    The stable carbon isotope composition of sedimentary organic carbon was determined in the sediments of seven coastal lagoons of the Gulf of Mexico, Mexico. For most of the lagoons the delta 13 C values for sediments ranged from -20.1 to -23.9 parts per thousand. Anomalously low values, -26.8 to 29.3 parts per thousand were determined in sediments of two of the studied lagoons, probably due to the presence of organic carbon from anthropogenic sources, naturally absent in these environments. The delta 13 C values determined in the tissues of oysters collected at the same time in the different lagoons were very similar to those recorded in the sediments. (author)

  6. Policy frameworks for adaptation to climate change in coastal zones. The case of the Gulf of Mexico

    International Nuclear Information System (INIS)

    Levina, E.; Jacob, J.S.; Ramos Bustillos, L.E.; Ortiz, I.

    2007-05-01

    This paper is the third in a series of AIXG (Annex I Expert Group on the United Nations Framework Convention on Climate Change (UNFCCC)) papers that analyse the roles that national policy frameworks of various sectors play in adaptation to climate change. Adaptation to climate change is unlikely to be a standalone process. It occurs within the existing sectoral and cross-sectoral policy frameworks, including legal provisions, institutional structures, policies and management practices, and is supported by the available information tools. The previous two papers focused on the water sector. The aim of this paper is to identify and analyse policy frameworks that are important for facilitating adaptation to climate change impacts in coastal zones. The paper is based on the analysis of the Gulf of Mexico. Two countries, the US and Mexico, are examined, with a focus on two aspects of coastal zones: wetlands and built environment. Next to these two sectors attention is paid to four components that construct policy frameworks, namely legal framework, institutional landscape, policies and management tools, and information. Following a brief introduction of the Gulf of Mexico region, its physical and economic characteristics, the paper takes a look at current climatic conditions and trends in the Gulf region and expected climate change impacts and the key vulnerabilities of the region to these changes (Section 2). The rational for the scope and focus of the sectoral analysis presented in this paper can also be found in Section 2. Section 3 focuses on the analysis of policy frameworks that govern wetlands in the US and Mexico and their links with adaptation. Section 4 focuses on the analysis of policy frameworks that govern the development of human settlements, and adaptation to climate change. Sections 3 and 4 follow a structure similar to the one that was used for the two previous papers on policy frameworks for adaptation in the water sector. Both sections examine

  7. A conceptual approach to integrate management of ecosystem service and disservice in coastal wetlands

    Directory of Open Access Journals (Sweden)

    Jon Knight

    2017-04-01

    Full Text Available Management of coastal wetlands is increasingly difficult because of increasing pressure arising from anthropogenic causes. These include sea level and climate change as well as coastline development caused by population growth and demographic shifts, for example, amenity migration where people move to coastal communities for lifestyle reasons. Management of mangroves and salt marshes is especially difficult because maintaining ecosystem values, including the goods and services provided, is countered by the potential of enhancing or even creating ecosystem disservices, such as unpleasant odour and mosquito hazards. Here we present, explain and apply a conceptual model aimed at improving understanding of management choices that primarily focus on mitigation of disservice while enabling improvement in ecosystem services. The model was developed after more than 30 years of habitat management following modification of a salt marsh to control mosquito production. We discuss the application of the model in a mangrove forest known to produce mosquitoes and outline the benefits arising from using the model.

  8. How to preserve coastal wetlands, threatened by climate change-driven rises in sea level.

    Science.gov (United States)

    Ivajnšič, Danijel; Kaligarič, Mitja

    2014-10-01

    A habitat transition model, based on the correlation between individual habitats and micro-elevation intervals, showed substantial changes in the future spatial distributions of coastal habitats. The research was performed within two protected areas in Slovenia: Sečovlje Salina Nature Park and Škocjan Inlet Nature Reserve. Shifts between habitats will occur, but a general decline of 42 % for all Natura 2000 habitats is projected by 2060, according to local or global (IPCC AR4) sea level rise predictions. Three different countermeasures for the long-term conservation of targeted habitat types were proposed. The most "natural" is displacement of coastal habitats using buffer zones (1) were available. Another solution is construction of artificial islets, made of locally dredged material (2); a feasible solution in both protected areas. Twenty-two islets and a dried salt pan zone at the desired elevations suitable for those habitats that have been projected to decease in area would offer an additional 10 ha in the Sečovlje Salina. Twenty-one islets and two peninsulas at two different micro-altitudes would ensure the survival of 13 ha of three different habitats. In the area of Sečovlje Salina, abandoned salt pans could be terrestrialized by using permanent, artificial sea barriers, in a manner close to poldering (3). By using this countermeasure, another 32 ha of targeted habitat could be preserved. It can be concluded that, for each coastal area, where wetland habitats will shrink, strategic plans involving any of the three solutions should be prepared well in advance. The specific examples provided might facilitate adaptive management of coastal wetlands in general.

  9. Degradation State and Sequestration Potential of Carbon in Coastal Wetlands of Texas: Mangrove Vs. Saltmarsh Ecosystems

    Science.gov (United States)

    Sterne, A. M. E.; Kaiser, K.; Louchouarn, P.; Norwood, M. J.

    2015-12-01

    The estimated magnitude of the organic carbon (OC) stocks contained in the first meter of US coastal wetland soils represents ~10% of the entire OC stock in US soils (4 vs. 52 Pg, respectively). Because this stock extends to several meters below the surface for many coastal wetlands, it becomes paramount to understand the fate of OC under ecosystem shifts, varying natural environmental constraints, and changing land use. In this project we analyze the major classes of biochemicals including total hydrolysable neutral carbohydrates, enantiomeric amino acids, phenols, and cutins/suberins at two study sites located on the Texas coastline to investigate chemical composition and its controls on organic carbon preservation in mangrove (Avicennia germinans) and saltmarsh grass (Spartina alterniflora) dominated wetlands. Results show neutral carbohydrates and lignin contribute 30-70% and 10-40% of total OC, respectively, in plant litter and surface sediments at both sites. Sharp declines of carbohydrate yields with depth occur parallel to increasing Ac/AlS,V ratios indicating substantial decomposition of both the polysaccharide and lignin components of litter detritus. Contrasts in the compositions and relative abundances of all previously mentioned compound classes are further discussed to examine the role of litter biochemistry in OC preservation. For example, the selective preservation of cellulose over hemicellulose in sediments indicates macromolecular structure plays a key role in preservation between plant types. It is concluded that the chemical composition of litter material controls the composition and magnitude of OC stored in sediments. Ultimately, as these ecosystems transition from one dominant plant type to another, as is currently observed along the Texas coastline, there is the potential for OC sequestration efficiency to shift due to the changing composition of OC input to sediments.

  10. Classifications for Coastal Wetlands Planning, Protection and Restoration Act site-specific projects: 2008 and 2009

    Science.gov (United States)

    Jones, William R.; Garber, Adrienne

    2012-01-01

    The Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) funds over 100 wetland restoration projects across Louisiana. Integral to the success of CWPPRA is its long-term monitoring program, which enables State and Federal agencies to determine the effectiveness of each restoration effort. One component of this monitoring program is the analysis of high-resolution, color-infrared aerial photography at the U.S. Geological Survey's National Wetlands Research Center in Lafayette, Louisiana. Color-infrared aerial photography (9- by 9-inch) is obtained before project construction and several times after construction. Each frame is scanned on a photogrametric scanner that produces a high-resolution image in Tagged Image File Format (TIFF). By using image-processing software, these TIFF files are then orthorectified and mosaicked to produce a seamless image of a project area and its associated reference area (a control site near the project that has common environmental features, such as marsh type, soil types, and water salinities.) The project and reference areas are then classified according to pixel value into two distinct classes, land and water. After initial land and water ratios have been established by using photography obtained before and after project construction, subsequent comparisons can be made over time to determine land-water change. Several challenges are associated with the land-water interpretation process. Primarily, land-water classifications are often complicated by the presence of floating aquatic vegetation that occurs throughout the freshwater systems of coastal Louisiana and that is sometimes difficult to differentiate from emergent marsh. Other challenges include tidal fluctuations and water movement from strong winds, which may result in flooding and inundation of emergent marsh during certain conditions. Compensating for these events is difficult but possible by using other sources of imagery to verify marsh conditions for other

  11. Soil color indicates carbon and wetlands: developing a color-proxy for soil organic carbon and wetland boundaries on sandy coastal plains in South Africa.

    Science.gov (United States)

    Pretorius, M L; Van Huyssteen, C W; Brown, L R

    2017-10-13

    A relationship between soil organic carbon and soil color is acknowledged-albeit not a direct one. Since heightened carbon contents can be an indicator of wetlands, a quantifiable relationship between color and carbon might assist in determining wetland boundaries by rapid, field-based appraisal. The overarching aim of this initial study was to determine the potential of top soil color to indicate soil organic carbon, and by extension wetland boundaries, on a sandy coastal plain in South Africa. Data were collected from four wetland types in northern KwaZulu-Natal in South Africa. Soil samples were taken to a depth of 300 mm in three transects in each wetland type and analyzed for soil organic carbon. The matrix color was described using a Munsell soil color chart. Various color indices were correlated with soil organic carbon. The relationship between color and carbon were further elucidated using segmented quantile regression. This showed that potentially maximal carbon contents will occur at values of low color indices, and predictably minimal carbon contents will occur at values of low or high color indices. Threshold values can thus be used to make deductions such as "when the sum of dry and wet Value and Chroma values is 9 or more, carbon content will be 4.79% and less." These threshold values can then be used to differentiate between wetland and non-wetland sites with a 70 to 100% certainty. This study successfully developed a quantifiable correlation between color and carbon and showed that wetland boundaries can be determined based thereon.

  12. Aquatic food webs in mangrove and seagrass habitats of Centla Wetland, a Biosphere Reserve in Southeastern Mexico

    Directory of Open Access Journals (Sweden)

    Manuel Mendoza-Carranza

    Full Text Available Mangrove and seagrass habitats are important components of tropical coastal zones worldwide, and are conspicuous habitats of Centla Wetland Biosphere Reserve (CWBR in Tabasco, Mexico. In this study, we examine food webs in mangrove- and seagrass-dominated habitats of CWBR using stable isotope ratios of carbon and nitrogen. Our objective was to identify the importance of carbon derived from mangroves and seagrasses to secondary production of aquatic consumers in this poorly studied conservation area. Carbon and nitrogen isotope ratios of basal sources and aquatic consumers indicated that the species-rich food webs of both habitats are dependent on riparian production sources. The abundant Red mangrove Rhizophora mangle appears to be a primary source of carbon for the mangrove creek food web. Even though dense seagrass beds were ubiquitous, most consumers in the lagoon food web appeared to rely on carbon derived from riparian vegetation (e.g. Phragmites australis. The introduced Amazon sailfin catfish Pterygoplichthys pardalis had isotope signatures overlapping with native species (including high-value fisheries species, suggesting potential competition for resources. Future research should examine the role played by terrestrial insects in linking riparian and aquatic food webs, and impacts of the expanding P. pardalis population on ecosystem function and fisheries in CWBR. Our findings can be used as a baseline to reinforce the conservation and management of this important reserve in the face of diverse external and internal human impacts.

  13. A Mechanistically Informed User-Friendly Model to Predict Greenhouse Gas (GHG) Fluxes and Carbon Storage from Coastal Wetlands

    Science.gov (United States)

    Abdul-Aziz, O. I.; Ishtiaq, K. S.

    2015-12-01

    We present a user-friendly modeling tool on MS Excel to predict the greenhouse gas (GHG) fluxes and estimate potential carbon sequestration from the coastal wetlands. The dominant controls of wetland GHG fluxes and their relative mechanistic linkages with various hydro-climatic, sea level, biogeochemical and ecological drivers were first determined by employing a systematic data-analytics method, including Pearson correlation matrix, principal component and factor analyses, and exploratory partial least squares regressions. The mechanistic knowledge and understanding was then utilized to develop parsimonious non-linear (power-law) models to predict wetland carbon dioxide (CO2) and methane (CH4) fluxes based on a sub-set of climatic, hydrologic and environmental drivers such as the photosynthetically active radiation, soil temperature, water depth, and soil salinity. The models were tested with field data for multiple sites and seasons (2012-13) collected from the Waquoit Bay, MA. The model estimated the annual wetland carbon storage by up-scaling the instantaneous predicted fluxes to an extended growing season (e.g., May-October) and by accounting for the net annual lateral carbon fluxes between the wetlands and estuary. The Excel Spreadsheet model is a simple ecological engineering tool for coastal carbon management and their incorporation into a potential carbon market under a changing climate, sea level and environment. Specifically, the model can help to determine appropriate GHG offset protocols and monitoring plans for projects that focus on tidal wetland restoration and maintenance.

  14. Nutrient and salt relations of Pterocarpus officinalis L. in coastal wetlands of the Caribbean: assessment through leaf and soil analyses.

    Science.gov (United States)

    Ernesto Medina; Elvira Cuevas; Ariel Lugo

    2007-01-01

    Pterocarpus officinalis L. is a dominant tree of freshwater coastal wetlands in the Caribbean and the Guiana regions. It is frequently associated with mangroves in areas with high rainfall and/or surface run-off. We hypothesized that P. officinalis is a freshwater swamp species that when occurring in association with mangroves occupies low-salinity soil microsites, or...

  15. Rapid Stable Isotope Turnover of Larval Fish in a Lake Superior Coastal Wetland: Implications for Diet and Life History Studies

    Science.gov (United States)

    Trophic linkages of larval fish in Lake Superior coastal wetlands, rivers and embayments can be identified using naturally occurring differences in the stable isotope ratios of nitrogen (15N:14N, ?15N) and carbon (13C:12C, ?13C). We sampled pelagic fish larvae weekly during sprin...

  16. Modeling the impacts of climate variability and hurricane on carbon sequestration in a coastal forested wetland in South Carolina

    Science.gov (United States)

    Zhaohua Dai; Carl C. Trettin; Changsheng Li; Ge Sun; Devendra M. Amatya; Harbin Li

    2013-01-01

    The impacts of hurricane disturbance and climate variability on carbon dynamics in a coastal forested wetland in South Carolina of USA were simulated using the Forest-DNDC model with a spatially explicit approach. The model was validated using the measured biomass before and after Hurricane Hugo and the biomass inventories in 2006 and 2007, showed that the Forest-DNDC...

  17. Coastal vulnerability index for the Tabasco State coast, Mexico

    Directory of Open Access Journals (Sweden)

    Juan Carlos Nuñez Gómez

    2016-11-01

    of the major lagoon system in the State of Tabasco, the Carmen-Pajonal-Machona and Mecoacan lagoons; being the last one the most vulnerable of all. It is worth pointing out that this zone is located within the influence zone of the Dos Bocas port where an intense anthropogenic activity occurs. It is also important to point out that this study is one of the first approaches to the estimation of coastal vulnerability in Mexico. The implementation and application of this model of coastal vulnerability evaluation are significant given the spatial scale of the study and that this is the first time that these variables have been collected for the state of Tabasco. Our results might inform decision-making processes on the proper management of the Tabasco coastline, thus benefiting the local communities.

  18. Combined influence of sedimentation and vegetation on the soil carbon stocks of a coastal wetland in the Changjiang estuary

    Science.gov (United States)

    Zhang, Tianyu; Chen, Huaipu; Cao, Haobing; Ge, Zhenming; Zhang, Liquan

    2017-07-01

    Coastal wetlands play an important role in the global carbon cycle. Large quantities of sediment deposited in the Changjiang (Yangtze) estuary by the Changjiang River promote the propagation of coastal wetlands, the expansion of saltmarsh vegetation, and carbon sequestration. In this study, using the Chongming Dongtan Wetland in the Changjiang estuary as the study area, the spatial and temporal distribution of soil organic carbon (SOC) stocks and the influences of sedimentation and vegetation on the SOC stocks of the coastal wetland were examined in 2013. There was sediment accretion in the northern and middle areas of the wetland and in the Phragmites australis marsh in the southern area, and sediment erosion in the Scirpus mariqueter marsh and the bare mudflat in the southern area. More SOC accumulated in sediments of the vegetated marsh than in the bare mudflat. The total organic carbon (TOC) stocks increased in the above-ground biomass from spring to autumn and decreased in winter; in the below-ground biomass, they gradually increased from spring to winter. The TOC stocks were higher in the below-ground biomass than in the above-ground biomass in the P. australis and Spartina alterniflora marshes, but were lower in the below-ground biomass in S. mariqueter marsh. Stocks of SOC showed temporal variation and increased gradually in all transects from spring to winter. The SOC stocks tended to decrease from the high marsh down to the bare mudflat along the three transects in the order: P. australis marsh > S. alterniflora marsh > S. mariqueter marsh > bare mudflat. The SOC stocks of the same vegetation type were higher in the northern and middle transects than in the southern transect. These results suggest that interactions between sedimentation and vegetation regulate the SOC stocks in the coastal wetland in the Changjiang estuary.

  19. Assessment of the content, structure, and source of soil dissolved organic matter in the coastal wetlands of Jiaozhou Bay, China

    Science.gov (United States)

    Xi, Min; Zi, Yuanyuan; Wang, Qinggai; Wang, Sen; Cui, Guolu; Kong, Fanlong

    2018-02-01

    The contents and the spectral analysis of dissolved organic matter (DOM) in four typical wetlands, such as naked tidal, suaeda salsa, reed and spartina, were conducted to investigate the content, structure, and source of DOM in coastal wetland soil. The soil samples were obtained from Jiaozhou Bay in January, April, July, and October of 2014. Results showed that the DOM contents in soil of four typical wetland were in order of spartina wetland > naked tidal > suaeda salsa wetland > reed wetland in horizontal direction, and decreased with the increase of soil depth on vertical section. In addition, the DOM contents changed with the seasons, in order of spring > summer > autumn > winter. The structural characteristics of DOM in Jiaozhou Bay wetland, such as aromaticity, hydrophobicity, molecular weight, polymerization degree of benzene ring carbon frame structure and so on were in order of spartina wetland > naked tidal > suaeda salsa wetland > reed wetland in the horizontal direction. On the vertical direction, they showed a decreasing trend with the increase of soil depth. The results of three dimensional fluorescence spectra and fluorescence spectrum parameters (FI, HIX, and BIX) indicated that the DOM in Jiaozhou Bay was mainly derived from the biological activities. The contents and structure of DOM had certain relevance, but the contents and source as well as the structure and source of DOM had no significant correlation. The external pollution including domestic sewage, industrial wastewater, and aquaculture sewage affected the correlation among the content, structure and source of DOM by influencing the percentage of non-fluorescent substance in DOM and disturbing the determination of protein-like fluorescence.

  20. Multi-temporal Land Use Mapping of Coastal Wetlands Area using Machine Learning in Google Earth Engine

    Science.gov (United States)

    Farda, N. M.

    2017-12-01

    Coastal wetlands provide ecosystem services essential to people and the environment. Changes in coastal wetlands, especially on land use, are important to monitor by utilizing multi-temporal imagery. The Google Earth Engine (GEE) provides many machine learning algorithms (10 algorithms) that are very useful for extracting land use from imagery. The research objective is to explore machine learning in Google Earth Engine and its accuracy for multi-temporal land use mapping of coastal wetland area. Landsat 3 MSS (1978), Landsat 5 TM (1991), Landsat 7 ETM+ (2001), and Landsat 8 OLI (2014) images located in Segara Anakan lagoon are selected to represent multi temporal images. The input for machine learning are visible and near infrared bands, PCA band, invers PCA bands, bare soil index, vegetation index, wetness index, elevation from ASTER GDEM, and GLCM (Harralick) texture, and also polygon samples in 140 locations. There are 10 machine learning algorithms applied to extract coastal wetlands land use from Landsat imagery. The algorithms are Fast Naive Bayes, CART (Classification and Regression Tree), Random Forests, GMO Max Entropy, Perceptron (Multi Class Perceptron), Winnow, Voting SVM, Margin SVM, Pegasos (Primal Estimated sub-GrAdient SOlver for Svm), IKPamir (Intersection Kernel Passive Aggressive Method for Information Retrieval, SVM). Machine learning in Google Earth Engine are very helpful in multi-temporal land use mapping, the highest accuracy for land use mapping of coastal wetland is CART with 96.98 % Overall Accuracy using K-Fold Cross Validation (K = 10). GEE is particularly useful for multi-temporal land use mapping with ready used image and classification algorithms, and also very challenging for other applications.

  1. Measurement and modelling of evaporation from a coastal wetland in Maputaland, South Africa

    Directory of Open Access Journals (Sweden)

    A. D. Clulow

    2012-09-01

    Full Text Available The surface renewal (SR method was used to determine the long-term (12 months total evaporation (ET from the Mfabeni Mire with calibration using eddy covariance during two window periods of approximately one week each. The SR method was found to be inexpensive, reliable and with low power requirements for unattended operation.

    Despite maximum ET rates of up to 6.0 mm day−1, the average summer (October to March ET was lower (3.2 mm day−1 due to early morning cloud cover that persisted until nearly midday at times. This reduced the daily available energy, and the ET was lower than expected despite the available water and high average wind speeds. In winter (May to September, there was less cloud cover but the average ET was only 1.8 mm day−1 due to plant senescence. In general ET was suppressed by the inflow of humid air (low vapour pressure deficit and the comparatively low leaf area index of the wetland vegetation. The accumulated ET over 12 months was 900 mm. Daily ET estimates were compared to the Priestley-Taylor model results and a calibration α = 1.0 (R2 = 0.96 was obtained for the site. A monthly crop factor (Kc was determined for the standardised FAO-56 Penman-Monteith. However, Kc was variable in some months and should be used with caution for daily ET modelling.

    These results represent not only some of the first long-term measurements of ET from a wetland in southern Africa, but also one of the few studies of actual ET in a subtropical peatland in the Southern Hemisphere. The study provides wetland ecologists and hydrologists with guidelines for the use of two internationally applied models for the estimation of wetland ET within a coastal, subtropical environment and shows that wetlands are not necessarily high water users.

  2. Wetlands and Sustainability

    Directory of Open Access Journals (Sweden)

    Richard Smardon

    2014-11-01

    Full Text Available This editorial provides an overview of the special issue “Wetlands and Sustainability”. In particular, the special issue contains a review of Paul Keddy’s book “Wetland Ecology” with specific reference to wetland sustainability. It also includes papers addressing wetland data acquisition via radar and remote sensing to better understand wetland system dynamics, hydrologic processes linked to wetland stress and restoration, coastal wetlands land use conflict/management, and wetland utilization for water quality treatment.

  3. Jiangsu coastal highland reclamation and its wetland ecological construction-a case analysis of the Tiaozini reclamation project

    Science.gov (United States)

    Yu, Meixiu; Xu, Xianghong

    2017-04-01

    Reclamation is one potential solution for the increasing demand of new land for living and development. In past centuries, many coastal countries, such as the Netherlands, UK, Japan, South Korea and Singapore, had exploited extensively sea enclosing and reclamation fordefense against storm surges,agricultural and industrial development, as well as for coastal city expansion along the coast. China has continuously reclaimed coastal sea areas from the 1950s. With rapid economic development and increasing population in coastal areas during recent decades, reclamation has been regarded as an effective measure to resolve the land shortage as cities and industries expand, particularly in South-East coastal areas. Jiangsu province, located in East China, has a similar amount of land territory area to the Netherlands, however, its population is almost fivefold instead. Since its coastal area generates large amounts of tidal flat resources due to its unique hydrodynamic and geomorphic conditions, coastal reclamation plays a vital role in guaranteeing the food security for the Jiangsu Province or even the whole nation. The Tiaozini Reclamation Project (TRP), located between N32.720°-32.882°, E120.894°-120.969°, in Jianggang county of Jiangsu coastal region, with an area of 6,746ha, was reclaimed along the prograding muddy silt coast in 2012. It should be noted that the TRP was reclaimed from theoretical bathymetrical datum of about 4.6m. It is estimated that the shoreline moves towards the sea at a rate of 100m/year and the tidal flat raises at a rate of 5 10 cm/year respectively because of the external tidal flat being continually prograding and drying. After finishing reclamation,the TRP develops with nature: for the dried tidal flat high land,developing ecological agriculture after integrated soil improvement with reducing salt and cultivating fertilizer; for the drying tidal flat,developing ecological fishery by inceasing artificial wetland area; for lower tidal flat

  4. A preliminary riparian/wetland vegetation community classification of the Upper and Middle Rio Grande watersheds in New Mexico

    Science.gov (United States)

    Paula Durkin; Esteban Muldavin; Mike Bradley; Stacey E. Carr

    1996-01-01

    The riparian wetland vegetation communities of the upper and middle Rio Grande watersheds in New Mexico were surveyed in 1992 through 1994. The communities are hierarchically classified in terms of species composition and vegetation structure. The resulting Community Types are related to soil conditions, hydrological regime, and temporal dynamics. The classification is...

  5. Ecological Effects of Roads on the Plant Diversity of Coastal Wetland in the Yellow River Delta

    Directory of Open Access Journals (Sweden)

    Yunzhao Li

    2014-01-01

    Full Text Available The 26 sample sites in 7 study plots adjacent to asphalt road and earth road in coastal wetland in the Yellow River Delta were selected to quantify plant diversity using quadrat sampling method in plant bloom phase of July and August 2012. The indice of βT and Jaccard’s coefficient were applied to evaluate the species diversity. The results showed that the plant diversities and alien plants were high in the range of 0–20 m to the road verge. There were more exotics and halophytes in plots of asphalt roadside than that of earth roadside. However, proportion of halophytes in habitats of asphalt roadsides was lower than that of earth roadside. By comparing β-diversity, there were more common species in the asphalt roadsides than that in the earth roadsides. The similarity of plant communities in studied plots of asphalt roadsides and earth roadsides increased with increasing the distance to road verge. The effect range of roads for plant diversity in study region was about 20 m to road verge. Our results indicate that the construction and maintenance of roads in wetland could increase the plant species diversities of communities and risk of alien species invasion.

  6. Ecological Effects of Roads on the Plant Diversity of Coastal Wetland in the Yellow River Delta

    Science.gov (United States)

    Li, Yunzhao; Du, Siyao; Han, Guangxuan; Qu, Fanzhu; Wang, Guangmei; Fu, Yuqin; Zhan, Chao

    2014-01-01

    The 26 sample sites in 7 study plots adjacent to asphalt road and earth road in coastal wetland in the Yellow River Delta were selected to quantify plant diversity using quadrat sampling method in plant bloom phase of July and August 2012. The indice of β T and Jaccard's coefficient were applied to evaluate the species diversity. The results showed that the plant diversities and alien plants were high in the range of 0–20 m to the road verge. There were more exotics and halophytes in plots of asphalt roadside than that of earth roadside. However, proportion of halophytes in habitats of asphalt roadsides was lower than that of earth roadside. By comparing β-diversity, there were more common species in the asphalt roadsides than that in the earth roadsides. The similarity of plant communities in studied plots of asphalt roadsides and earth roadsides increased with increasing the distance to road verge. The effect range of roads for plant diversity in study region was about 20 m to road verge. Our results indicate that the construction and maintenance of roads in wetland could increase the plant species diversities of communities and risk of alien species invasion. PMID:25147872

  7. Coastal regime shifts: rapid responses of coastal wetlands to changes in mangrove cover.

    Science.gov (United States)

    Guo, Hongyu; Weaver, Carolyn; Charles, Sean P; Whitt, Ashley; Dastidar, Sayantani; D'Odorico, Paolo; Fuentes, Jose D; Kominoski, John S; Armitage, Anna R; Pennings, Steven C

    2017-03-01

    Global changes are causing broad-scale shifts in vegetation communities worldwide, including coastal habitats where the borders between mangroves and salt marsh are in flux. Coastal habitats provide numerous ecosystem services of high economic value, but the consequences of variation in mangrove cover are poorly known. We experimentally manipulated mangrove cover in large plots to test a set of linked hypotheses regarding the effects of changes in mangrove cover. We found that changes in mangrove cover had strong effects on microclimate, plant community, sediment accretion, soil organic content, and bird abundance within 2 yr. At higher mangrove cover, wind speed declined and light interception by vegetation increased. Air and soil temperatures had hump-shaped relationships with mangrove cover. The cover of salt marsh plants decreased at higher mangrove cover. Wrack cover, the distance that wrack was distributed from the water's edge, and sediment accretion decreased at higher mangrove cover. Soil organic content increased with mangrove cover. Wading bird abundance decreased at higher mangrove cover. Many of these relationships were non-linear, with the greatest effects when mangrove cover varied from zero to intermediate values, and lesser effects when mangrove cover varied from intermediate to high values. Temporal and spatial variation in measured variables often peaked at intermediate mangrove cover, with ecological consequences that are largely unexplored. Because different processes varied in different ways with mangrove cover, the "optimum" cover of mangroves from a societal point of view will depend on which ecosystem services are most desired. © 2016 by the Ecological Society of America.

  8. Developing Remote Sensing Products for Monitoring and Modeling Great Lakes Coastal Wetland Vulnerability to Climate Change and Land Use

    Science.gov (United States)

    Bourgeau-Chavez, L. L.; Miller, M. E.; Battaglia, M.; Banda, E.; Endres, S.; Currie, W. S.; Elgersma, K. J.; French, N. H. F.; Goldberg, D. E.; Hyndman, D. W.

    2014-12-01

    Spread of invasive plant species in the coastal wetlands of the Great Lakes is degrading wetland habitat, decreasing biodiversity, and decreasing ecosystem services. An understanding of the mechanisms of invasion is crucial to gaining control of this growing threat. To better understand the effects of land use and climatic drivers on the vulnerability of coastal zones to invasion, as well as to develop an understanding of the mechanisms of invasion, research is being conducted that integrates field studies, process-based ecosystem and hydrological models, and remote sensing. Spatial data from remote sensing is needed to parameterize the hydrological model and to test the outputs of the linked models. We will present several new remote sensing products that are providing important physiological, biochemical, and landscape information to parameterize and verify models. This includes a novel hybrid radar-optical technique to delineate stands of invasives, as well as natural wetland cover types; using radar to map seasonally inundated areas not hydrologically connected; and developing new algorithms to estimate leaf area index (LAI) using Landsat. A coastal map delineating wetland types including monocultures of the invaders (Typha spp. and Phragmites austrailis) was created using satellite radar (ALOS PALSAR, 20 m resolution) and optical data (Landsat 5, 30 m resolution) fusion from multiple dates in a Random Forests classifier. These maps provide verification of the integrated model showing areas at high risk of invasion. For parameterizing the hydrological model, maps of seasonal wetness are being developed using spring (wet) imagery and differencing that with summer (dry) imagery to detect the seasonally wet areas. Finally, development of LAI remote sensing high resolution algorithms for uplands and wetlands is underway. LAI algorithms for wetlands have not been previously developed due to the difficulty of a water background. These products are being used to

  9. Investigations of subsurface flow constructed wetlands and associated geomaterial resources in the Akumal and Reforma regions, Quintana Roo, Mexico

    Science.gov (United States)

    Krekeler, Mark P. S.; Probst, Pete; Samsonov, Misha; Tselepis, Cynthia M.; Bates, William; Kearns, Lance E.; Maynard, J. Barry

    2007-12-01

    Subsurface flow constructed wetlands in the village of Akumal, Quintana Roo, Mexico were surveyed to determine the general status of the wetland systems and provide baseline information for long term monitoring and further study. Twenty subsurface flow wetlands were surveyed and common problems observed in the systems were overloading, poor plant cover, odor, and no secondary containment. Bulk mineral composition of aggregate from two subsurface flow constructed wetlands was determined to consist solely of calcite using bulk powder X-ray diffraction. Some soil structure is developed in the aggregate and aggregate levels in wetlands drop at an estimated rate between 3 and 10 cm/year for overloaded wetlands owing to dissolution. Mineral composition from fresh aggregate samples commonly is a mixture of calcite and aragonite. Trace amounts of Pb, Zn, Co, and Cr were observed in fresh aggregate. Coefficients of permeability ( k) varied from 0.006 to 0.027 cm/s with an average values being 0.016 cm/s. Grain size analysis of fresh aggregate samples indicates there are unimodal and multimodal size distributions in the samples with modes in the coarse and fine sand being common. Investigations of other geologic media from the Reforma region indicate that a dolomite with minor amounts of Fe-oxide and palygorskite is abundant and may be a better aggregate source that the current materials used. A Ca-montmorillonite bed was identified in the Reforma region as well and this unit is suitable to serve as a clay liner to prevent leaks for new and existing wetland systems. These newly discovered geologic resources should aid in the improvement of subsurface flow constructed wetlands in the region. Although problems do exist in these wetlands with respect to design, these systems represent a successful implementation of constructed wetlands at a community level in developing regions.

  10. Environmental evolution records reflected by radionuclides in the sediment of coastal wetlands: A case study in the Yellow River Estuary wetland.

    Science.gov (United States)

    Wang, Qidong; Song, Jinming; Li, Xuegang; Yuan, Huamao; Li, Ning; Cao, Lei

    2016-10-01

    Vertical profiles of environmental radionuclides ( 210 Pb, 137 Cs, 238 U, 232 Th, 226 Ra and 4 0 K) in a sediment core (Y1) of the Yellow River Estuary wetland were investigated to assess whether environmental evolutions in the coastal wetland could be recorded by the distributions of radionuclides. Based on 210 Pb and 137 Cs dating, the average sedimentation rate of core Y1 was estimated to be 1.0 cm y -1 . Vertical distributions of natural radionuclides ( 238 U, 232 Th, 226 Ra and 40 K) changed dramatically, reflecting great changes in sediment input. Concentrations of 238 U, 232 Th, 226 Ra and 40 K all had significant positive relationships with organic matter and clay content, but their distributions were determined by different factors. Factor analysis showed that 238 U was determined by the river sediment input while 226 Ra was mainly affected by the seawater erosion. Environmental changes such as river channel migrations and sediment discharge variations could always cause changes in the concentrations of radionuclides. High concentrations of 238 U and 226 Ra were consistent with high accretion rate. Frequent seawater intrusion decreased the concentration of 226 Ra significantly. The value of 238 U/ 226 Ra tended to be higher when the sedimentation rate was low and tide intrusion was frequent. In summary, environmental evolutions in the estuary coastal wetland could be recorded by the vertical profiles of natural radionuclides. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Seawater and Freshwater Circulations through Coastal Forested Wetlands on a Caribbean Island

    Directory of Open Access Journals (Sweden)

    Luc Lambs

    2015-07-01

    Full Text Available Structure and composition of coastal forested wetlands are mainly controlled by local topography and soil salinity. Hydrology plays a major role in relation with tides, seaward, and freshwater inputs, landward. We report here the results of a two-year study undertaken in a coastal plain of the Guadeloupe archipelago (FWI. As elsewhere in the Caribbean islands, the study area is characterized by a micro-tidal regime and a highly seasonal climate. This work aimed at understanding groundwater dynamics and origin (seawater/freshwater both at ecosystems and stand levels. These hydrological processes were assessed through 18O/16O and 2H/1H isotopic analyses, and from monthly monitoring of water level and soil salinity at five study sites located in mangrove (3 and swamp forest (2. Our results highlight the importance of freshwater budget imbalance during low rainfall periods. Sustained and/or delayed dry seasons cause soil salinity to rise at the mangrove/swamp forest ecotone. As current models on climate change project decreasing rainfall amounts over the inner Caribbean region, one may expect for this area an inland progression of the mangrove forest to the expense of the nearby swamp forest.

  12. Food Web Response to Habitat Restoration in Various Coastal Wetland Ecosystems

    Science.gov (United States)

    James, W. R.; Nelson, J. A.

    2017-12-01

    Coastal wetland habitats provide important ecosystem services, including supporting coastal food webs. These habitats are being lost rapidly. To combat the effects of these losses, millions of dollars have been invested to restore these habitats. However, the relationship between restoring habitat and restoring ecosystem functioning is poorly understood. Analyzing energy flow through food web comparisons between restored and natural habitats can give insights into ecosystem functioning. Using published stable isotope values from organisms in restored and natural habitats, we assessed the food web response of habitat restoration in salt marsh, mangrove, sea grass, and algal bed ecosystems. We ran Bayesian mixing models to quantify resource use by consumers and generated habitat specific niche hypervolumes for each ecosystem to assess food web differences between restored and natural habitats. Salt marsh, mangrove, and sea grass ecosystems displayed functional differences between restored and natural habitats. Salt marsh and mangrove food webs varied in the amount of each resource used, while the sea grass food web displayed more variation between individual organisms. The algal bed food web showed little variation between restored and natural habitats.

  13. Factors influencing CO2 and CH4 emissions from coastal wetlands in the Liaohe Delta, Northeast China

    DEFF Research Database (Denmark)

    Olsson, L.; Ye, S.; Wei, M.

    2015-01-01

    temperature and vegetation on CH4 emissions and ecosystem respiration (Reco) from five coastal wetlands in the Liaohe Delta, northeast China: two Phragmites australis (common reed) wetlands, two Suaeda salsa (sea blite) marshes and a rice (Oryza sativa) paddy. Throughout the growing season, the Suaeda...

  14. U.S. Coastal Relief Model - Western Gulf of Mexico

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC's U.S. Coastal Relief Model (CRM) provides the first comprehensive view of the U.S. coastal zone integrating offshore bathymetry with land topography into a...

  15. U.S. Coastal Relief Model - Central Gulf of Mexico

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC's U.S. Coastal Relief Model (CRM) provides the first comprehensive view of the U.S. coastal zone integrating offshore bathymetry with land topography into a...

  16. Wetland Accretion Rates Along Coastal Louisiana: Spatial and Temporal Variability in Light of Hurricane Isaac’s Impacts

    Directory of Open Access Journals (Sweden)

    Thomas A. Bianchette

    2015-12-01

    Full Text Available The wetlands of the southern Louisiana coast are disappearing due to a host of environmental stressors. Thus, it is imperative to analyze the spatial and temporal variability of wetland vertical accretion rates. A key question in accretion concerns the role of landfalling hurricanes as a land-building agent, due to their propensity to deposit significant volumes of inorganic sediments. Since 1996, thousands of accretion measurements have been made at 390 sites across coastal Louisiana as a result of a regional monitoring network, called the Coastal Reference Monitoring System (CRMS. We utilized this dataset to analyze the spatial and temporal patterns of accretion by mapping rates during time periods before, around, and after the landfall of Hurricane Isaac (2012. This analysis is vital for quantifying the role of hurricanes as a land-building agent and for understanding the main mechanism causing heightened wetland accretion. The results show that accretion rates averaged about 2.89 cm/year from stations sampled before Isaac, 4.04 cm/year during the period encompassing Isaac, and 2.38 cm/year from sites established and sampled after Isaac. Accretion rates attributable to Isaac’s effects were therefore 40% and 70% greater than before and after the event, respectively, indicating the event’s importance toward coastal land-building. Accretion associated with Isaac was highest at sites located 70 kilometers from the storm track, particularly those near the Mississippi River and its adjacent distributaries and lakes. This spatial pattern of elevated accretion rates indicates that freshwater flooding from fluvial channels, rather than storm surge from the sea per se, is the main mechanism responsible for increased wetland accretion. This significance of riverine flooding has implications toward future coastal restoration policies and practices.

  17. Studying the impact of climate change on coastal aquifers and adjacent wetlands

    Science.gov (United States)

    Stigter, Tibor; Ribeiro, Luís.; Oliveira, Rodrigo; Samper, Javier; Fakir, Younes; Fonseca, Luís.; Monteiro, José Paulo; Nunes, João. Pedro; Pisani, Bruno

    2010-05-01

    program, assessing the impact of climate change on coastal groundwater resources and dependent ecosystems. These resources are often intensively exploited, potentially leading to saltwater intrusion and the degradation of groundwater and dependent wetlands. Climate change may increase this problem in Mediterranean regions, due to the combined effect of rising sea levels and decreasing aquifer recharge. CLIMWAT aims to address this problem by employing a multimethodological approach involving climate scenarios, surface and groundwater flow and transport modeling, as well as hydrochemical indicator and ecological diversity indices. Research is performed in three coastal areas: the Central Algarve in Portugal, the Ebro delta in Spain and the Atlantic Sahel in Morocco. The mean annual temperatures are 17.4 ° C, 17.2 ° C and 17.5 ° C, respectively, whereas mean annual rainfall is lower in the Atlantic Sahel (390 mm) than in the Ebro Delta (520 mm) and the Central Algarve (660 mm). Work package (WP) 1 involves the collection of existing data (in a GIS environment), baseline characterization and the selection of monitoring locations. These include wells and springs of official (water level/quality) monitoring networks, as well as additional observation points selected at strategic locations, including the wetlands receiving groundwater and adjacent aquifer sectors. In WP2 the climate scenarios are selected and integrated in hydrological models (SWAT, GISBALAN), which are developed and calibrated with existing data, prior to scenario modeling. The main focus of this WP is to estimate the evolution of surface runoff and groundwater recharge under climate change. Data on climate change scenarios and model projections are compiled from: (i) the PRUDENCE project; (ii) the ENSEMBLES project; (iii) IPCC scenarios and projections, AR4; (iv) AEMet (Spanish Meteorological Agency) for generation of regional scenarios of climate change in Spain. For Morocco, where runoff is

  18. Development of a Bi-National Great Lakes Coastal Wetland and Land Use Map Using Three-Season PALSAR and Landsat Imagery

    Directory of Open Access Journals (Sweden)

    Laura Bourgeau-Chavez

    2015-07-01

    Full Text Available Methods using extensive field data and three-season Landsat TM and PALSAR imagery were developed to map wetland type and identify potential wetland stressors (i.e., adjacent land use for the United States and Canadian Laurentian coastal Great Lakes. The mapped area included the coastline to 10 km inland to capture the region hydrologically connected to the Great Lakes. Maps were developed in cooperation with the overarching Great Lakes Consortium plan to provide a comprehensive regional baseline map suitable for coastal wetland assessment and management by agencies at the local, tribal, state, and federal levels. The goal was to provide not only land use and land cover (LULC baseline data at moderate spatial resolution (20–30 m, but a repeatable methodology to monitor change into the future. The prime focus was on mapping wetland ecosystem types, such as emergent wetland and forested wetland, as well as to delineate wetland monocultures (Typha, Phragmites, Schoenoplectus and differentiate peatlands (fens and bogs from other wetland types. The overall accuracy for the coastal Great Lakes map of all five lake basins was 94%, with a range of 86% to 96% by individual lake basin (Huron, Ontario, Michigan, Erie and Superior.

  19. Bat Response To Carolina Bays and Wetland Restoration in the Southeastern U.S. Coastal Plain

    Science.gov (United States)

    Jennifer M. Menzel; Michael A. Menzel; John C. Kilgo; W. Mark Ford; John W. Edwards

    2005-01-01

    Bat activity in the southeastern United States is concentrated over riparian areas and wetland habitats. The restoration and creation of wetlands for mitigation purposes is becoming common in the Southeast. Understanding the effects of these restoration efforts on wetland flora and fauna is thus becoming increasingly important. Because bats (Order: Chiroptera) consist...

  20. Chronic warming stimulates growth of marsh grasses more than mangroves in a coastal wetland ecotone.

    Science.gov (United States)

    Coldren, G A; Barreto, C R; Wykoff, D D; Morrissey, E M; Langley, J A; Feller, I C; Chapman, S K

    2016-11-01

    Increasing temperatures and a reduction in the frequency and severity of freezing events have been linked to species distribution shifts. Across the globe, mangrove ranges are expanding toward higher latitudes, likely due to diminishing frequency of freezing events associated with climate change. Continued warming will alter coastal wetland plant dynamics both above- and belowground, potentially altering plant capacity to keep up with sea level rise. We conducted an in situ warming experiment, in northeast Florida, to determine how increased temperature (+2°C) influences co-occurring mangrove and salt marsh plants. Warming was achieved using passive warming with three treatment levels (ambient, shade control, warmed). Avicennia germinans, the black mangrove, exhibited no differences in growth or height due to experimental warming, but displayed a warming-induced increase in leaf production (48%). Surprisingly, Distichlis spicata, the dominant salt marsh grass, increased in biomass (53% in 2013 and 70% in 2014), density (41%) and height (18%) with warming during summer months. Warming decreased plant root mass at depth and changed abundances of anaerobic bacterial taxa. Even while the poleward shift of mangroves is clearly controlled by the occurrences of severe freezes, chronic warming between these freeze events may slow the progression of mangrove dominance within ecotones. © 2016 by the Ecological Society of America.

  1. Ground-Truthing of Airborne LiDAR Using RTK-GPS Surveyed Data in Coastal Louisiana's Wetlands

    Science.gov (United States)

    Lauve, R. M.; Alizad, K.; Hagen, S. C.

    2017-12-01

    Airborne LiDAR (Light Detection and Ranging) data are used by engineers and scientists to create bare earth digital elevation models (DEM), which are essential to modeling complex coastal, ecological, and hydrological systems. However, acquiring accurate bare earth elevations in coastal wetlands is difficult due to the density of marsh grasses that prevent the sensors reflection off the true ground surface. Previous work by Medeiros et al. [2015] developed a technique to assess LiDAR error and adjust elevations according to marsh vegetation density and index. The aim of this study is the collection of ground truth points and the investigation on the range of potential errors found in existing LiDAR datasets within coastal Louisiana's wetlands. Survey grids were mapped out in an area dominated by Spartina alterniflora and a survey-grade Trimble Real Time Kinematic (RTK) GPS device was employed to measure bare earth ground elevations in the marsh system adjacent to Terrebonne Bay, LA. Elevations were obtained for 20 meter-spaced surveyed grid points and were used to generate a DEM. The comparison between LiDAR derived and surveyed data DEMs yield an average difference of 23 cm with a maximum difference of 68 cm. Considering the local tidal range of 45 cm, these differences can introduce substantial error when the DEM is used for ecological modeling [Alizad et al., 2016]. Results from this study will be further analyzed and implemented in order to adjust LiDAR-derived DEMs closer to their true elevation across Louisiana's coastal wetlands. ReferencesAlizad, K., S. C. Hagen, J. T. Morris, S. C. Medeiros, M. V. Bilskie, and J. F. Weishampel (2016), Coastal wetland response to sea-level rise in a fluvial estuarine system, Earth's Future, 4(11), 483-497, 10.1002/2016EF000385. Medeiros, S., S. Hagen, J. Weishampel, and J. Angelo (2015), Adjusting Lidar-Derived Digital Terrain Models in Coastal Marshes Based on Estimated Aboveground Biomass Density, Remote Sensing, 7

  2. Perceptions of Village Dogs by Villagers and Tourists in the Coastal Region of Rural Oaxaca, Mexico

    NARCIS (Netherlands)

    Ruiz Izaguirre, E.; Eilers, C.H.A.M.

    2012-01-01

    The objective of this study was to gain an understanding of the village dog-keeping system, and of perceptions of dog-related problems by villagers and tourists, in the coastal region of Oaxaca, Mexico. We conducted a survey of the inhabitants of three villages (Mazunte, Puerto Angel, and Río Seco),

  3. Hurricane storm surge and amphibian communities in coastal wetlands of northwestern Florida

    Science.gov (United States)

    Gunzburger, M.S.; Hughes, W.B.; Barichivich, W.J.; Staiger, J.S.

    2010-01-01

    Isolated wetlands in the Southeastern United States are dynamic habitats subject to fluctuating environmental conditions. Wetlands located near marine environments are subject to alterations in water chemistry due to storm surge during hurricanes. The objective of our study was to evaluate the effect of storm surge overwash on wetland amphibian communities. Thirty-two wetlands in northwestern Florida were sampled over a 45-month period to assess amphibian species richness and water chemistry. During this study, seven wetlands were overwashed by storm surge from Hurricane Dennis which made landfall 10 July 2005 in the Florida panhandle. This event allowed us to evaluate the effect of storm surge overwash on water chemistry and amphibian communities of the wetlands. Specific conductance across all wetlands was low pre-storm (marine habitats are resistant to the effects of storm surge overwash. ?? 2010 Springer Science+Business Media B.V.

  4. Palynological reconstruction of environmental changes in coastal wetlands of the Florida Everglades since the mid-Holocene

    Science.gov (United States)

    Yao, Qiang; Liu, Kam-biu; Platt, William J.; Rivera-Monroy, Victor H.

    2015-05-01

    Palynological, loss-on-ignition, and X-ray fluorescence data from a 5.25 m sediment core from a mangrove forest at the mouth of the Shark River Estuary in the southwestern Everglades National Park, Florida were used to reconstruct changes occurring in coastal wetlands since the mid-Holocene. This multi-proxy record contains the longest paleoecological history to date in the southwestern Everglades. The Shark River Estuary basin was formed 5700 cal yr BP in response to increasing precipitation. Initial wetlands were frequently-burned short-hydroperiod prairies, which transitioned into long-hydroperiod prairies with sloughs in which peat deposits began to accumulate continuously about 5250 cal yr BP. Our data suggest that mangrove communities started to appear after 3800 cal yr BP; declines in the abundance of charcoal suggested gradual replacement of fire-dominated wetlands by mangrove forest over the following 2650 yr. By 1150 cal yr BP, a dense Rhizophora mangle dominated mangrove forest had formed at the mouth of the Shark River. The mangrove-dominated coastal ecosystem here was established at least 2000 yr later than has been previously estimated.

  5. Gulf of Mexico Integrated Science - Tampa Bay Study - Characterization of Tidal Wetlands

    Science.gov (United States)

    McIvor, Carole

    2005-01-01

    Tidal wetlands in Tampa Bay, Florida, consist of mangrove forests and salt marshes. Wetlands buffer storm surges, provide fish and wildlife habitat, and enhance water quality through the removal of water-borne nutrients and contaminants. Substantial areas of both mangroves and salt marshes have been lost to agricultural, residential, and industrial development in this urban estuary. Wetlands researchers are characterizing the biological components of tidal wetlands and examining the physical factors such as salinity, tidal flushing, and sediment deposition that control the composition of tidal wetland habitats. Wetlands restoration is a priority of resource managers in Tampa Bay. Baseline studies such as these are needed for successful restoration planning and evaluation.

  6. Climatic change and variability: The effects of an altered water regime on Great Lakes coastal wetlands

    International Nuclear Information System (INIS)

    Mortsch, L.

    1990-01-01

    Wetlands of Canada are disappearing at a rapid rate due to urban encroachment and agricultural land drainage. Climatic change may be another threat to their continued viability. Wetlands perform numerous functions such as providing wildlife habitat, enhancing water quality, providing recreation opportunities and supporting commercial activities. Impact scenarios of global warming on Great Lakes hydrology and wetland ecosystem response to water level changes are tabulated. Wetland response to lower annual water levels depends on the type of wetland, its geomorphology and bathymetry. Marshes and open water wetland adapt more readily to lower levels than swamps. Swamps are less resilient since trees cannot regenerate and colonize quickly. Enclosed and barrier beach wetlands are more prone to drying out and loosing wetland vegetation during low water periods. In open shoreline wetlands, the areal extent could increase if there is a gentle slope and other suitable conditions. Precambrian Shield wetlands are located in areas of irregular slope and rocky substrate, and would have fewer sites for successful colonization. 15 refs., 2 tabs

  7. Effects of drought and salt stresses on growth characteristics of euhalophyte Suaeda salsa in coastal wetlands

    Science.gov (United States)

    Jia, Jia; Huang, Chen; Bai, Junhong; Zhang, Guangliang; Zhao, Qingqing; Wen, Xiaojun

    2018-02-01

    The pot experiment was carried out in the Yellow River Delta to investigate the effects of drought and salt stresses on growth characteristics of Suaeda salsa, and to reveal the role of nitrogen (N) application in alleviation effects of drought and salt stresses on Suaeda salsa in coastal wetlands. In this study, plants were exposed to two water contents treatments (i.e., 14% and 26% water content), four salinity treatments (i.e., 2 g/kg, 4 g/kg, 6 g/kg, and 8 g/kg NaCl) and two N application treatments (i.e., 0 and 200 N mg/kg) in field conditions. Growth characteristics of Suaeda salsa were assessed as fresh weight, dry weight, height, total nitrogen (TN) and total carbon (TC). Our results showed that fresh weight, dry weight and height of Suaeda salsa promoted at lower salinity treatments but reduced at higher salinity treatments, while TN and TC contents kept stable with increasing salinity levels. Drought stress diminished the fresh weight, dry weight and height of Suaeda salsa, whereas enhanced TN contents. Under the interactive stresses of drought and salt, fresh weight and dry weight showed slight increases at lower salinity treatments, whereas decreases at higher salinity treatments. N application promoted the fresh weight, dry weight and TN contents other than the height and TC contents of Suaeda salsa. The interaction between N application and salt stress exhibited a significant influence on the fresh weight and dry weight of Suaeda salsa, whereas no significant interaction between N application and drought stress was observed. These findings of this study suggested that higher salinity, drought and the interaction of drought and higher salinity would retard the growth of Suaeda salsa, whereas N application could only mitigate the deleterious effects of salt stress on Suaeda salsa.

  8. Integrated hydrological modelling of a managed coastal Mediterranean wetland (Rhone delta, France: initial calibration

    Directory of Open Access Journals (Sweden)

    P. Chauvelon

    2003-01-01

    Full Text Available This paper presents a model of a heavily managed coastal Mediterranean wetland. The hydrosystem studied , called ``Ile de Camargue', is the central part of the Rhone river delta. It comprises flat agricultural drainage basins, marshes, and shallow brackish lagoons whose connection to the sea is managed. This hydrosystem is subject to strong natural hydrological variability due to the combination of a Mediterranean climate and the artificial hydrological regime imposed by flooded rice cultivation. To quantify the hydrological balance at different spatial and temporal scales, a simplified model is developed — including the basin and the lagoons — using a time step that enables the temporal dynamic to be reproduced that is adapted to data availability. This modelling task takes into account the functioning of the natural and anthropogenic components of the hydrosystem. A conceptual approach is used for modelling drainage from the catchment, using a GIS to estimate water input for rice irrigation. The lagoon system is modelled using a two-dimensional finite element hydrodynamic model. Simulated results from the hydrodynamic model run under various hydro-climatic forcing conditions (water level, wind speed and direction, sea connection are used to calculate hydraulic exchanges between lagoon sub units considered as boxes. Finally, the HIC ('Hydrologie de l’Ile de Camargue' conceptual model is applied to simulate the water inputs and exchanges between the different units, together with the salt balance in the hydrosystem during a calibration period. Keywords: water management,conceptual hydrological model, hydrodynamic model, box model, GIS, Rhone delta, Camargue.

  9. Dissolved organic matter dynamics in the oligo/meso-haline zone of wetland-influenced coastal rivers

    Science.gov (United States)

    Maie, Nagamitsu; Sekiguchi, Satoshi; Watanabe, Akira; Tsutsuki, Kiyoshi; Yamashita, Youhei; Melling, Lulie; Cawley, Kaelin M.; Shima, Eikichi; Jaffé, Rudolf

    2014-08-01

    Wetlands are key components in the global carbon cycle and export significant amounts of terrestrial carbon to the coastal oceans in the form of dissolved organic carbon (DOC). Conservative behavior along the salinity gradient of DOC and chromophoric dissolved organic matter (CDOM) has often been observed in estuaries from their freshwater end-member (salinity = 0) to the ocean (salinity = 35). While the oligo/meso-haline (salinity DOC and CDOM optical properties determined by UV absorbance at 254 nm (A254) and excitation-emission matrix (EEM) fluorescence coupled with parallel factor analysis (PARAFAC) along the lower salinity range (salinity DOC and A254 was observed, while these parameters showed similar conservative behavior for the third. Three distinct EEM-PARAFAC models established for each of the rivers provided similar spectroscopic characteristics except for some unique fluorescence features observed for the Judan River. The distribution patterns of PARAFAC components suggested that the inputs from plankton and/or submerged aquatic vegetation can be important in the Bekanbeushi River. Further, DOM photo-products formed in the estuarine lake were also found to be transported upstream. In the Harney River, whereas upriver-derived terrestrial humic-like components were mostly distributed conservatively, some of these components were also derived from mangrove inputs in the oligo/meso-haline zone. Interestingly, fluorescence intensities of some terrestrial humic-like components increased with salinity for the Judan River possibly due to changes in the dissociation state of acidic functional groups and/or increase in the fluorescence quantum yield along the salinity gradient. The protein-like and microbial humic-like components were distributed differently between three wetland rivers, implying that interplay between loss to microbial degradation and inputs from diverse sources are different for the three wetland-influenced rivers. The results presented here

  10. Spatial an temporal analysis of chloride concentrations in underground water in the coastal wetland of l'Albufera, Spain

    Science.gov (United States)

    Puhakka, Evelina; Pascual-Aguilar, Juan Antonio; Andreu, Vicente

    2010-05-01

    Mediterranean coastal wetlands are of great interest for their richness in biodiversity. They are also fragile systems because they are exposed to various human pressures, such as farming systems and urban sprawl. Most Mediterranean coastal wetlands have a transient underground inter phase of continental and marine water. In many cases, the variations of the rain regime towards an increasing dryness and the overexploitation of aquiphers in these zones could favour the marine water intrusion, being a source of continental water salinisation and loss of its quality. This process can directly affect the ecosystems and produce loss of biodiversity. Thus, studies to assess the dynamics in time and space of the possible marine intrusion are necessary to evaluate coastal environment health and quality. The study has been applied to L'Albufera Natural Park, the largest Coastal Wetland in eastern Spain. Due to its importance, it has been included in the list of Wetlands of the RAMSAR Convention. In the area there is a complex relationship between the intrinsic natural importance (endemicity and biodiversity) and the human activities (traditional agriculture and hinterland industrial and settlement development). The methodological approach is based in the analysis of chloride concentrations time series of thirteen sample water points distributed in and around the boundaries of the Natural Park. All time series, between 1982 and 2008, have been analysed to establish trends both in time and space. Results show that in samples close to the see (between 1500 and 2000 metres) chloride concentrations are not too high, with values between 37 mg/l and 213 mg/l. Nonetheless, the shorter is the distance to the see the higher are the chloride levels, with values between 58 mg/l and 1131 mg/l. For longer distances, more than 2000 from the coast line, values are quite similar in most sample points, from 52 mg/l to 691 mg/l. Among all the thirteen time series analysed trends are detected

  11. A Carbon Cycle Model for the Social-Ecological Process in Coastal Wetland: A Case Study on Gouqi Island, East China

    Directory of Open Access Journals (Sweden)

    Yanxia Li

    2017-01-01

    Full Text Available Coastal wetlands offer many important ecosystem services both in natural and in social systems. How to simultaneously decrease the destructive effects flowing from human activities and maintaining the sustainability of regional wetland ecosystems are an important issue for coastal wetlands zones. We use carbon credits as the basis for regional sustainable developing policy-making. With the case of Gouqi Island, a typical coastal wetlands zone that locates in the East China Sea, a carbon cycle model was developed to illustrate the complex social-ecological processes. Carbon-related processes in natural ecosystem, primary industry, secondary industry, tertiary industry, and residents on the island were identified in the model. The model showed that 36780 tons of carbon is released to atmosphere with the form of CO2, and 51240 tons of carbon is captured by the ecosystem in 2014 and the three major resources of carbon emission are transportation and tourism development and seawater desalination. Based on the carbon-related processes and carbon balance, we proposed suggestions on the sustainable development strategy of Gouqi Island as coastal wetlands zone.

  12. A Carbon Cycle Model for the Social-Ecological Process in Coastal Wetland: A Case Study on Gouqi Island, East China

    Science.gov (United States)

    Xiong, Lihu; Zhu, Wenjia

    2017-01-01

    Coastal wetlands offer many important ecosystem services both in natural and in social systems. How to simultaneously decrease the destructive effects flowing from human activities and maintaining the sustainability of regional wetland ecosystems are an important issue for coastal wetlands zones. We use carbon credits as the basis for regional sustainable developing policy-making. With the case of Gouqi Island, a typical coastal wetlands zone that locates in the East China Sea, a carbon cycle model was developed to illustrate the complex social-ecological processes. Carbon-related processes in natural ecosystem, primary industry, secondary industry, tertiary industry, and residents on the island were identified in the model. The model showed that 36780 tons of carbon is released to atmosphere with the form of CO2, and 51240 tons of carbon is captured by the ecosystem in 2014 and the three major resources of carbon emission are transportation and tourism development and seawater desalination. Based on the carbon-related processes and carbon balance, we proposed suggestions on the sustainable development strategy of Gouqi Island as coastal wetlands zone. PMID:28286690

  13. Persistent organochlorine pollutants (POP's) in coastal environments of Southeast Gulf of Mexico

    International Nuclear Information System (INIS)

    Vazquez-Botello, A.; Diaz-Gonzalez, G.; Rueda-Quintana, L.

    1999-01-01

    Analyses to determine the presence and concentrations of persistent organochlorine pollutants (POP's) were carried out in sediments and estuarine organisms (Crassostrea virginica) from five coastal lagoons of the Southeast Gulf of Mexico. The results of this study show high levels of POP's in sediments with high concentration of Heptachlor, Aldrin, Dieldrin and ppDDT, either in sediments or biological tissues. According to national regulations, the use and dispersion of these chemical have been severely restricted or totally prohibited in developed countries, however their presence in coastal areas indicate an extensive use and recent application of them. (author)

  14. Hydrodynamics of the groundwater-fed Sian Ka'an Wetlands, Mexico, From InSAR and SAR Data

    DEFF Research Database (Denmark)

    Gondwe, Bibi Ruth Neuman; Hong, S.; Wdowinski, S.

    2008-01-01

    The 5300 km2 pristine Sian Ka'an wetland in Mexico is fed entirely by groundwater from the karst aquifer of the Yucatan Peninsula. The area is undeveloped and hence difficult to access. The inflow through underground rivers and karst structures is hard to observe resulting in difficulties......-changes of the backscattered radar signal, which can be related to the water level changes in vegetated wetlands. SAR data reveals information of surface properties such as the degree of flooding through the amplitude of the backscattered signal. We used RADARSAT-1 InSAR and SAR data to form 36 interferograms and 13 flooding...... maps with 24 to 48 day intervals covering the time span of October 2006 to March 2008. The dataset has a high spatial resolution of ca. 20 to 60 m. Sian Ka'an consists of a mosaic of freshwater sloughs, canals, floodplains and brackish tidally-influenced areas. Throughout most of the year, water level...

  15. Coastal change and hypoxia in the northern Gulf of Mexico: Part I

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available The Committee on Environment and Natural Resources (CENR has identified the input of nutrient-rich water from the Mississippi/Atchafalaya River Basin (MARB as the prime cause of hypoxia in the northern Gulf of Mexico and the prime means for its control. A Watershed Nutrient Task Force was formed to solve the hypoxia problem by managing the MARB catchment. However, the hypoxic zone is also experiencing massive physical, hydrological, chemical and biological changes associated with an immense river-switching and delta-building event that occurs here about once a millennium. Coastal change induced hypoxia in the northern Gulf of Mexico prior to European settlement. It is recommended that for further understanding and control of Gulf hypoxia the Watershed Nutrient Task Force adopt a truly holistic environmental approach which includes the full effects of this highly dynamic coastal area.

  16. Feeding ecology of juvenile marine fish in a shallow coastal lagoon of southeastern Mexico

    OpenAIRE

    Daniel Arceo-Carranza; Xavier Chiappa-Carrara

    2015-01-01

    Many species of marine fish use coastal lagoons during early stages of their life cycles due to the protection provided by their turbid waters and complex structure of the environment, such as mangroves and mudflats, and the availability of food derived from the high productivity of these sites. In this study, we analyzed the diet of six species of juvenile marine fishes that use a karstic lagoon system in the northwest portion of the Yucatan Peninsula, Mexico. Through stomach contents analys...

  17. Comparison of the quantitative determination of soil organic carbon in coastal wetlands containing reduced forms of Fe and S

    Science.gov (United States)

    Passos, Tassia R. G.; Artur, Adriana G.; Nóbrega, Gabriel N.; Otero, Xosé L.; Ferreira, Tiago O.

    2016-06-01

    The performance of the Walkley-Black wet oxidation chemical method for soil organic carbon (SOC) determination in coastal wetland soils (mangroves, coastal lagoons, and hypersaline tidal flats) was evaluated in the state of Ceará along the semiarid coast of Brazil, assessing pyrite oxidation and its effects on soil C stock (SCS) quantification. SOC determined by the chemical oxidation method (CWB) was compared to that assessed by means of a standard elemental analyzer (CEA) for surficial samples (mangroves, whereas lower values were found in the other settings. CWB values were higher than CEA values. Significant differences in SCS calculations based on CWB and CEA were recorded for the coastal lagoons and hypersaline tidal flats. Nevertheless, the CWB and CEA values were strongly correlated, indicating that the wet oxidation chemical method can be used in such settings. In contrast, the absence of correlation for the mangroves provides evidence of the inadequacy of this method for these soils. Air drying and oxidation decrease the pyrite content, with larger effects rooted in oxidation. Thus, the wet oxidation chemical method is not recommended for mangrove soils, but seems appropriate for SOC/SCS quantification in hypersaline tidal flat and coastal lagoon soils characterized by lower pyrite contents.

  18. Direct and indirect controls on organic matter decomposition in four coastal wetland communities along a landscape salinity gradient

    Science.gov (United States)

    Stagg, Camille L.; Baustian, Melissa M.; Perry, Carey L.; Carruthers, Tim J.B.; Hall, Courtney T.

    2018-01-01

    Coastal wetlands store more carbon than most ecosystems globally. As sea level rises, changes in flooding and salinity will potentially impact ecological functions, such as organic matter decomposition, that influence carbon storage. However, little is known about the mechanisms that control organic matter loss in coastal wetlands at the landscape scale. As sea level rises, how will the shift from fresh to salt-tolerant plant communities impact organic matter decomposition? Do long-term, plant-mediated, effects of sea-level rise differ from direct effects of elevated salinity and flooding?We identified internal and external factors that regulated indirect and direct pathways of sea-level rise impacts, respectively, along a landscape-scale salinity gradient that incorporated changes in wetland type (fresh, oligohaline, mesohaline and polyhaline marshes). We found that indirect and direct impacts of sea-level rise had opposing effects on organic matter decomposition.Salinity had an indirect effect on litter decomposition that was mediated through litter quality. Despite significant variation in environmental conditions along the landscape gradient, the best predictors of above- and below-ground litter decomposition were internal drivers, initial litter nitrogen content and initial litter lignin content respectively. Litter decay constants were greatest in the oligohaline marsh and declined with increasing salinity, and the fraction of litter remaining (asymptote) was greatest in the mesohaline marsh. In contrast, direct effects of salinity and flooding were positive. External drivers, salinity and flooding, stimulated cellulytic activity, which was highest in the polyhaline marsh.Synthesis. Our results indicate that as sea level rises, initial direct effects of salinity will stimulate decay of labile carbon, but over time as plant communities shift from fresh to polyhaline marsh, litter decay will decline, yielding greater potential for long-term carbon storage

  19. Associations between the molecular and optical properties of dissolved organic matter in the Florida Everglades, a model coastal wetland system

    Science.gov (United States)

    Wagner, Sasha; Jaffe, Rudolf; Cawley, Kaelin; Dittmar, Thorsten; Stubbins, Aron

    2015-11-01

    Optical properties are easy-to-measure proxies for dissolved organic matter (DOM) composition, source and reactivity. However, the molecular signature of DOM associated with such optical parameters remains poorly defined. The Florida coastal Everglades is a subtropical wetland with diverse vegetation (e.g., sawgrass prairies, mangrove forests, seagrass meadows) and DOM sources (e.g., terrestrial, microbial and marine). As such, the Everglades is an excellent model system from which to draw samples of diverse origin and composition to allow classically-defined optical properties to be linked to molecular properties of the DOM pool. We characterized a suite of seasonally- and spatially-collected DOM samples using optical measurements (EEM-PARAFAC, SUVA254, S275-295, S350-400, SR, FI, freshness index and HIX) and ultrahigh resolution mass spectrometry (FTICR-MS). Spearman’s rank correlations between FTICR-MS signal intensities of individual molecular formulae and optical properties determined which molecular formulae were associated with each PARAFAC component and optical index. The molecular families that tracked with the optical indices were generally in agreement with conventional biogeochemical interpretations. Therefore, although they represent only a small portion of the bulk DOM pool, absorbance and fluorescence measurements appear to be appropriate proxies for the aquatic cycling of both optically-active and associated optically-inactive DOM in coastal wetlands.

  20. Associations between the molecular and optical properties of dissolved organic matter in the Florida Everglades, a model coastal wetland system

    Directory of Open Access Journals (Sweden)

    Sasha eWagner

    2015-11-01

    Full Text Available Optical properties are easy-to-measure proxies for dissolved organic matter (DOM composition, source and reactivity. However, the molecular signature of DOM associated with such optical parameters remains poorly defined. The Florida coastal Everglades is a subtropical wetland with diverse vegetation (e.g., sawgrass prairies, mangrove forests, seagrass meadows and DOM sources (e.g., terrestrial, microbial and marine. As such, the Everglades is an excellent model system from which to draw samples of diverse origin and composition to allow classically-defined optical properties to be linked to molecular properties of the DOM pool. We characterized a suite of seasonally- and spatially-collected DOM samples using optical measurements (EEM-PARAFAC, SUVA254, S275-295, S350-400, SR, FI, freshness index and HIX and ultrahigh resolution mass spectrometry (FTICR-MS. Spearman’s rank correlations between FTICR-MS signal intensities of individual molecular formulae and optical properties determined which molecular formulae were associated with each PARAFAC component and optical index. The molecular families that tracked with the optical indices were generally in agreement with conventional biogeochemical interpretations. Therefore, although they represent only a small portion of the bulk DOM pool, absorbance and fluorescence measurements appear to be appropriate proxies for the aquatic cycling of both optically-active and associated optically-inactive DOM in coastal wetlands.

  1. 77 FR 39648 - Atlantic Highly Migratory Species; Commercial Gulf of Mexico Non-Sandbar Large Coastal Shark Fishery

    Science.gov (United States)

    2012-07-05

    ... Large Coastal Shark Fishery AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... commercial fishery for non-sandbar large coastal sharks (LCS) in the Gulf of Mexico region. This action is.... SUPPLEMENTARY INFORMATION: The Atlantic shark fisheries are managed under the 2006 Consolidated Atlantic Highly...

  2. A comparison of resident fish assemblages in managed and unmanaged coastal wetlands in North Carolina and South Carolina

    Science.gov (United States)

    Robinson, Kelly F.; Jennings, Cecil A.

    2014-01-01

    The dominant fish species within impounded coastal wetlands in the southeastern US may be different from the species that dominate natural marshes. We tested the hypothesis that resident fish assemblages inhabiting impounded coastal wetlands in South Carolina would differ from resident assemblages in natural marshes of the southeastern United States. We used rarefied species richness, Shannon's H' diversity,J' evenness, Morisita's index of similarity, and the percent similarity index to compare resident fish assemblages from two impoundments to 12 open-marsh resident fish assemblages from previously published studies in North and South Carolina. We used rotenone to sample fish assemblages in impoundments. The assemblages in natural marsh habitat had been sampled with rotenone and seines. We classified comparisons yielding a similarity index ≥0.50 as moderately similar and those with an index ≥0.75 as very similar. Fifty-three percent of the among-impoundment comparisons (Morisita's index) were at least moderately similar, whereas 7% of impoundment—natural marsh comparisons were moderately similar. A difference in tidal influence was the only parameter in the best-fitting model describing the observed Morisita's indices. The index of similarity decreased by 63% when tidal influence differed between compared assemblages. Species richness and diversity were greater in impoundments than natural marshes, but evenness was similar between habitat types. Our results support the hypothesis that resident fish assemblages in impounded wetlands and natural marshes are different, and suggest that a degree of tidal influence is the most important factor behind the difference.

  3. Modeled CO2 Emissions from Coastal Wetland Transitions to Other Land Uses: Tidal Marshes, Mangrove Forests, and Seagrass Beds

    Directory of Open Access Journals (Sweden)

    Catherine E. Lovelock

    2017-05-01

    Full Text Available The sediments of coastal wetlands contain large stores of carbon which are vulnerable to oxidation once disturbed, resulting in high levels of CO2 emissions that may be avoided if coastal ecosystems are conserved or restored. We used a simple model to estimate CO2 emissions from mangrove forests, seagrass beds, and tidal marshes based on known decomposition rates for organic matter in these ecosystems under either oxic or anoxic conditions combined with assumptions of the proportion of sediment carbon being deposited in either oxic or anoxic environments following a disturbance of the habitat. Our model found that over 40 years after disturbance the cumulative CO2 emitted from tidal marshes, mangrove forests, and seagrass beds were ~70–80% of the initial carbon stocks in the top meter of the sediment. Comparison of our estimates of CO2 emissions with empirical studies suggests that (1 assuming 50% of organic material moves to an oxic environment after disturbance gives rise to estimates that are similar to CO2 emissions reported for tidal marshes; (2 field measurements of CO2 emissions in disturbed mangrove forests were generally higher than our modeled emissions that assumed 50% of organic matter was deposited in oxic conditions, suggesting higher proportions of organic matter may be exposed to oxic conditions after disturbance in mangrove ecosystems; and (3 the generally low observed rates of CO2 emissions from disturbed seagrasses compared to our estimates, assuming removal of 50% of the organic matter to oxic environments, suggests that lower proportions may be exposed to oxic conditions in seagrass ecosystems. There are significant gaps in our knowledge of the fate of wetland sediment carbon in the marine environment after disturbance. Greater knowledge of the distribution, form, decomposition, and emission rates of wetland sediment carbon after disturbance would help to improve models.

  4. In-situ Geotechnical Characterization of Wetland Channel Cross Sections in Coastal Louisiana Using a Portable Free-fall Penetrometer

    Science.gov (United States)

    Bilici, C.; Stark, N.; Ghose Hajra, M.

    2016-02-01

    Broader comprehension of sediment dynamics in wetland channels is essential to protect and restore wetland areas in a sustainable manner. This study focused on a wetland channel located west of Lake Borgne in coastal Louisiana. In-situ tests were performed using a portable free fall penetrometer (PFFP), targeting the characterization of wetland channel sediment characteristics and dynamics. Data were collected at 102 locations along 3 cross-channel transects. Results indicated distinct variations in sediment properties across the channel. Sediments located centrally in the channel were soft and exhibited a similar sediment strength along the channel (0.75 - 3.5 kPa at 20 cm below channel bed surface; 4 - 10 kPa at 100 cm). The sediment strength near the channel banks increased up to 20 kPa at 20 cm below channel bed, while sediment samples did not indicate a significant variation in sediment type. Thus, surficial sediments located at the center of channel appeared less consolidated than at the channel banks. This likely resulted from erosion removing looser sediments due to differences in channel flow patterns or wake waves from boat activity. Furthermore, the thickness of a loose sediment top layer varied for the opposing banks of transects. This may be related to local changes in channel shape. Particularly in meandering parts of the channels, loose sediment layers were limited up to a thickness of 5 cm at the outer bank of individual meanders, while it reached a thickness of 15 cm at the inner bank. This matched the expectations of erosion at the outer banks and deposition on the inner banks. At some locations, asymmetric sediment layers on opposing banks of channel transects were likely related to local channel tributaries. These tributaries may act as a sediment sink or source affecting sedimentation in the investigated channel.

  5. Bat response to carolina bays and wetland restoration in the southeastern U.S. Coastal Plain.

    Energy Technology Data Exchange (ETDEWEB)

    Menzel, Jennifer M.; Michael A. Menzel; John C. Kilgo; W. Mark Ford; ; John W. Edwards.

    2005-09-01

    Abstract: Bat activity in the southeastern United States is concentrated over riparian areas and wetland habitats. The restoration and creation of wetlands for mitigation purposes is becoming common in the Southeast. Understanding the effects of these restoration efforts on wetland flora and fauna is thus becoming increasingly important. Because bats (Order: Chiroptera) consist of many species that are of conservation concern and are commonly associated with wetland and riparian habitats in the Southeast (making them a good general indicator for the condition of wetland habitats), we monitored bat activity over restored and reference Carolina bays surrounded by pine savanna (Pinus spp.) or mixed pine-hardwood habitat types at the Savannah River Site in South Carolina. In order to determine how wetland restoration efforts affected the bat community, we monitored bat activity above drained Carolina bays pre- and post-restoration. Our results indicate that bat activity was greater over reference (i.e., undrained) than drained bays prior to the restorative efforts. One year following combined hydrologic and vegetation treatment, however, bat activity was generally greater over restored than reference bays. Bat activity was also greater over both reference and restored bays than in random, forested interior locations. We found significantly more bat activity after restoration than prior to restoration for all but one species in the treatment bays, suggesting that Carolina bay restoration can have almost immediate positive impacts on bat activity.

  6. Sustainability of coastal resource use in San Quintin, Mexico.

    Science.gov (United States)

    Aguirre-Muñoz, A; Buddemeier, R W; Camacho-Ibar, V; Carriquiry, J D; Ibarra-Obando, S E; Massey, B W; Smith, S V; Wulff, F

    2001-05-01

    San Quintin, Mexico, provides a useful site for integrated analyses of material fluxes and socioeconomic constraints in a geographically isolated system. Natural resource utilization on the land is dominated by groundwater exploitation for cultivation of horticulture crops (primarily tomatoes). Irrigation exceeds water recharge minus export by a factor of 6. Resource utilization in the bay is dominated by oyster culture; food for the oysters is provided by tidal exchange of bay and ocean water. Consideration of oyster respiration and system respiration suggests that the present level of aquaculture is about 40% of the sustainable level. A "physical unsustainability index" (PhUI) was developed to measure the proportional departure of utilization of the most limiting resource for sustainability: 6 on land; 0.4 in the bay. Based on PhUI and measures of economic development, we conclude that aquaculture is more viable than agriculture.

  7. Ecological health status of the Lagos wetland ecosystems: Implications for coastal risk reduction

    Science.gov (United States)

    Agboola, Julius I.; Ndimele, Prince E.; Odunuga, Shakirudeen; Akanni, Adeniran; Kosemani, Bosede; Ahove, Michael A.

    2016-12-01

    Lagos, a major urban agglomeration in the world is characterized by wetlands and basin for upstream rivers such as Ogun, Oshun and Yewa Rivers. Ongoing environmental pressures exerted by large-scale land reclamation for residential quarters, refuse and sewage dumping, and other uses, however, are suspected to have had a substantial impact on ecological health of the Lagos wetland ecosystems over the last few decades. To determine the impact of these pressures, we examined spatial changes in three wetlands areas- Badore/Langbasa (BL), Festac/Iba/Ijegun (FI) and Ologe/Otto-Awori (OO) through field sample collection and analyses of surface water, sediments, air-water interface gas fluxes and vegetations. Surface water conductivity, total suspended solids (TSS), alkalinity, chloride, biological oxygen demand (BOD), nitrate, phosphate and heavy metals (Zn, Cu, Fe, Na, Mn, Pb, Cd, K and Ni) exhibited relative spatial stability while other water quality parameters varied significantly (P International Union for Conservation of Nature (IUCN). There are indications of steady rise in greenhouse gas levels in Lagos since air CO2 value at BL have reached global threshold of 400 ppm with OO and FI closely approaching. We conclude that the Lagos wetland ecosystems, especially OO and FI still have some semblance of natural habitat. However, further destruction and unwise use of the resources could cause damage to physical, chemical, geological and biological processes in nature, which could result to grave socio-economic and cultural consequences to the local communities whose livelihood and lifestyle depend on these valued wetlands.

  8. Reprint of Ecological health status of the Lagos wetland ecosystems: Implications for coastal risk reduction

    Science.gov (United States)

    Agboola, Julius I.; Ndimele, Prince E.; Odunuga, Shakirudeen; Akanni, Adeniran; Kosemani, Bosede; Ahove, Michael A.

    2016-12-01

    Lagos, a major urban agglomeration in the world is characterized by wetlands and basin for upstream rivers such as Ogun, Oshun and Yewa Rivers. Ongoing environmental pressures exerted by large-scale land reclamation for residential quarters, refuse and sewage dumping, and other uses, however, are suspected to have had a substantial impact on ecological health of the Lagos wetland ecosystems over the last few decades. To determine the impact of these pressures, we examined spatial changes in three wetlands areas- Badore/Langbasa (BL), Festac/Iba/Ijegun (FI) and Ologe/Otto-Awori (OO) through field sample collection and analyses of surface water, sediments, air-water interface gas fluxes and vegetations. Surface water conductivity, total suspended solids (TSS), alkalinity, chloride, biological oxygen demand (BOD), nitrate, phosphate and heavy metals (Zn, Cu, Fe, Na, Mn, Pb, Cd, K and Ni) exhibited relative spatial stability while other water quality parameters varied significantly (P International Union for Conservation of Nature (IUCN). There are indications of steady rise in greenhouse gas levels in Lagos since air CO2 value at BL have reached global threshold of 400 ppm with OO and FI closely approaching. We conclude that the Lagos wetland ecosystems, especially OO and FI still have some semblance of natural habitat. However, further destruction and unwise use of the resources could cause damage to physical, chemical, geological and biological processes in nature, which could result to grave socio-economic and cultural consequences to the local communities whose livelihood and lifestyle depend on these valued wetlands.

  9. Advanced data processing of airborne electromagnetic data for imaging hidden conduit networks in the coastal karst plain of Tulum (Mexico)

    International Nuclear Information System (INIS)

    Schiller, A.; Schattauer, I.; Ottowitz, D.

    2016-01-01

    This study is part of a series of international research cooperations which commenced in 2007 and are still ongoing. The study area is located on the east coast of the Yucatan Peninsula, Mexico, and comprises the northern most part of the Sian Kaan biosphere reserve, a coastal wetland of international importance, as well as the city of Tulum in the state of Quintana Roo, and part of the second largest barrier reef in the world some 300 metres to one kilometre off shore. Two airborne surveys, conducted in 2007 and 2008 by the Geological Survey of Austria, covered an area of some 200 square kilometres, including the well-known Ox Bel Ha cave system, already mapped by exploration divers. In order to get additional ground truth data and input for the hydrological model, extended ground geophysical campaigns have been conducted an - nually. The first processing of the airborne electromagnetic (AEM) data revealed not only a clear signature from known caves but also the image of a vast, unexplored, hidden conduit network. However, lateral and depth resolution was limited due to measurement drift and noise as well the specific behaviour of the ap - plied inversion technique. Newly developed algorithms for processing AEM data and inversion results have improved the signal-to-noise ratio significantly and enabled the imaging of well defined structures in the underground. Therefore, the AEM method is now capable of quickly deliver crucial structural information of karst-water regimes in difficult accessible areas with unique depth information compared to previous studies. (Author)

  10. Managing for No Net Loss of Ecological Services: An Approach for Quantifying Loss of Coastal Wetlands due to Sea Level Rise.

    Science.gov (United States)

    Kassakian, Jennifer; Jones, Ann; Martinich, Jeremy; Hudgens, Daniel

    2017-05-01

    Sea level rise has the potential to substantially alter the extent and nature of coastal wetlands and the critical ecological services they provide. In making choices about how to respond to rising sea level, planners are challenged with weighing easily quantified risks (e.g., loss of property value due to inundation) against those that are more difficult to quantify (e.g., loss of primary production or carbon sequestration services provided by wetlands due to inundation). Our goal was to develop a cost-effective, appropriately-scaled, model-based approach that allows planners to predict, under various sea level rise and response scenarios, the economic cost of wetland loss-with the estimates proxied by the costs of future restoration required to maintain the existing level of wetland habitat services. Our approach applies the Sea Level Affecting Marshes Model to predict changes in wetland habitats over the next century, and then applies Habitat Equivalency Analysis to predict the cost of restoration projects required to maintain ecological services at their present, pre-sea level rise level. We demonstrate the application of this approach in the Delaware Bay estuary and in the Indian River Lagoon (Florida), and discuss how this approach can support future coastal decision-making.

  11. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: Bare Earth

    Science.gov (United States)

    Smith, Kathryn E.L.; Nayegandhi, Amar; Wright, C. Wayne; Bonisteel, Jamie M.; Brock, John C.

    2009-01-01

    These remotely sensed, geographically referenced elevation measurements of Lidar-derived bare earth (BE) topography were produced as a collaborative effort between the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL; the National Park Service (NPS), Gulf Coast Network, Lafayette, LA; and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. The purpose of this project is to provide highly detailed and accurate datasets of select barrier islands and peninsular regions of Louisiana, Mississippi, Alabama, and Florida, acquired on June 27-30, 2007. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using

  12. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: First Surface

    Science.gov (United States)

    Smith, Kathryn E.L.; Nayegandhi, Amar; Wright, C. Wayne; Bonisteel, Jamie M.; Brock, John C.

    2009-01-01

    These remotely sensed, geographically referenced elevation measurements of Lidar-derived first surface (FS) elevation data were produced as a collaborative effort between the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL; the National Park Service (NPS), Gulf Coast Network, Lafayette, LA; and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. The project provides highly detailed and accurate datasets of select barrier islands and peninsular regions of Louisiana, Mississippi, Alabama, and Florida, acquired June 27-30, 2007. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system

  13. Mid term monitoring of heavy metals content in soils of Mediterranean coastal wetlands. La Albufera de Valencia Natural Park, Spain

    Science.gov (United States)

    Pascual-Aguilar, Juan Antonio; Andreu, Vicente; Gimeno-García, Eugenia

    2014-05-01

    Coastal wetlands, in general, and Mediterranean ones, in particular, suffer from differente anthropogenic pressures that may affect their intrinsic environmental and ecological functions. Most, if not all, Mediterranean wetlands are not natural spaces were preservation of habitat and wildlife is the only management policy achieved, bur rather their terriroty is a combination of land units with different activities and influences, such as farming, environmental protection and connectivities with urban and industrial areas. Therefore, the need of periodical monitoring is required whenever pressures and environmental health of wetlands is assessed, particularly of those processes that affect the interconnection of environmental compartiments involving water, soils and biota. In agro-ecological protected wetlands soils play and important role because they are potential sources of pollutants due to farming practices. In this case, presence of heavy metals in soils is and indicator of both environmental health and anthtopogenic direct (farming activities) and indirect (neighbour urban areas) pressures. In this work a mid term (17 year) monitoring of seven heavy metals (Cd, Co, Cr, Cu, Pb, Ni and Zn) in soils of coastal Mediterranean wetlands (La Albufera Natural Park, Spain) are analyzed. Two monitoring campaings were achieved in 1991 and 2008. In both cases the same 20 points were visited which were distributed in the natural park according two four different sectors of potential anthropogenic pressure and land use. At each point two soil samples were collected at differente depths (0 to 20 cm and 20 to 40 cm). The selected metals were analyzed to determine its total and extractable fractions by treatment with EDTA. Atomic Absorption Spectrometry, using graphite furnace when necessary, was used for the determination of metals. In general, there is a reduction of metal contents in the study area in both dates. The trend of metals according to average concentration (mg

  14. An inventory of wetland non-passerine birds along a southeastern Brazilian coastal area

    OpenAIRE

    D.C. Tavares; S. Siciliano

    2013-01-01

    This paper presents the list of non-passerine birds of coastal environments of the Quissama municipality, northern Rio de Janeiro State, southeastern Brazil. The surveys were conducted monthly between June 2011 and May 2012. Additional ad libitum observations were made between February 2008 and July 2012. We recorded 76 waterbird species of 15 families, of which Scolopacidae was the most representative, with 15 species. The high Nearctic shorebird species richness observed in coastal lagoo...

  15. Summary of Training Workshop on the Use of NASA tools for Coastal Resource Management in the Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Judd, Chaeli; Judd, Kathleen S.; Gulbransen, Thomas C.; Thom, Ronald M.

    2009-03-01

    A two-day training workshop was held in Xalapa, Mexico from March 10-11 2009 with the goal of training end users from the southern Gulf of Mexico states of Campeche and Veracruz in the use of tools to support coastal resource management decision-making. The workshop was held at the computer laboratory of the Institute de Ecologia, A.C. (INECOL). This report summarizes the results of that workshop and is a deliverable to our NASA client.

  16. Monitoring Ecological and Environmental Changes in Coastal Wetlands in the Yellow River Delta from 1987 to 2010 Using Remote Sensing Techniques

    Science.gov (United States)

    Shang, Kun; Zhao, Dong; Gan, Fuping; Xiao, Chenchao

    2016-04-01

    Many wetlands in the world have degraded rapidly in recent years, especially in China. The Yellow River Delta (YRD) is one of the largest deltas in China. The YRD Nature Reserve is one of China's most complete, broadest, and youngest wetland ecological systems in the warm-temperate zone. Most previous studies have placed particular emphasis on ecological environment or landscape of the YRD based on the distribution of wetlands. In recent years, with the rapid development of the city of Dongying, located in the YRD, the impacts of human activities are increasingly significant, so that monitoring changes in the wetlands has become especially important. In this research, we applied an improved Support Vector Machine (SVM) approach to wetland classification based on feature band set construction and optimization using seven Landsat images. By extracting waterlines, classifying wetlands and deriving landscape parameters, we have achieved high-frequency comprehensive monitoring of the wetlands in the YRD over a relatively long period. It offers a better estimate of wetland change trends than certain previous studies. From 1987 to 2010, the natural waterline primarily experienced erosion due to precipitation abnormalities, as well as coastal exploitation, as the co-analyzed meteorological data suggest. Meanwhile, the artificial waterline barely changed. The wetland area decreased rapidly from approximately 4,607 km2 to 2,714 km2 between 1987 and 2000. Ecological resilience and landscape diversity also decreased significantly during this period. The major impact factors were most likely urbanization, population expansion and the exploitation of the wetlands. After 2000, ecological resilience exhibited a positive trend. However, because newly built aquatic farms and salt works caused serious damages and threatened the natural beach landscape, the landscape fragmentation of muddy and sandy beaches increased after 2000. According to the results, more effective policies and

  17. Soil physicochemical conditions, denitrification rates, and nosZ abundance in North Carolina Coastal Plain restored wetlands

    Science.gov (United States)

    Ever since the United States adopted a national policy of wetland “No Net Loss”, a variety of measures have been aimed at restoring wetland biogeochemical function to former wetland areas. Nitrogen is a key element controlled by properly functioning wetlands, particularly when they are located adjac...

  18. Assessing Nature-Based Coastal Protection against Disasters Derived from Extreme Hydrometeorological Events in Mexico

    Directory of Open Access Journals (Sweden)

    Octavio Pérez-Maqueo

    2018-04-01

    Full Text Available Natural ecosystems are expected to reduce the damaging effects of extreme hydrometeorological effects. We tested this prediction for Mexico by performing regression models, with two dependent variables: the occurrence of deaths and economic damages, at a state and municipality levels. For each location, the explanatory variables were the Mexican social vulnerability index (which includes socioeconomic aspects, local capacity to prevent and respond to an emergency, and the perception of risk and land use cover considering different vegetation types. We used the hydrometeorological events that have affected Mexico from 1970 to 2011. Our findings reveal that: (a hydrometeorological events affect both coastal and inland states, although damages are greater on the coast; (b the protective role of natural ecosystems only was clear at a municipality level: the presence of mangroves, tropical dry forest and tropical rainforest was related to a significant reduction in the occurrence of casualties. Social vulnerability was positively correlated with the occurrence of deaths. Natural ecosystems, both typically coastal (mangroves and terrestrial (tropical forests, which are located on the mountain ranges close to the coast function for storm protection. Thus, their conservation and restoration are effective and sustainable strategies that will help protect and develop the increasingly urbanized coasts.

  19. Contaminants in the coastal karst aquifer system along the Caribbean coast of the Yucatan Peninsula, Mexico

    International Nuclear Information System (INIS)

    Metcalfe, Chris D.; Beddows, Patricia A.; Bouchot, Gerardo Gold; Metcalfe, Tracy L.; Li Hongxia; Van Lavieren, Hanneke

    2011-01-01

    Intensive land development as a result of the rapidly growing tourism industry in the 'Riviera Maya' region of the Yucatan Peninsula, Mexico may result in contamination of groundwater resources that eventually discharge into Caribbean coastal ecosystems. We deployed two types of passive sampling devices into groundwater flowing through cave systems below two communities to evaluate concentrations of contaminants and to indicate the possible sources. Pharmaceuticals and personal care products accumulated in the samplers could only have originated from domestic sewage. PAHs indicated contamination by runoff from highways and other impermeable surfaces and chlorophenoxy herbicides accumulated in samplers deployed near a golf course indicated that pesticide applications to turf are a source of contamination. Prevention and mitigation measures are needed to ensure that expanding development does not impact the marine environment and human health, thus damaging the tourism-based economy of the region. - Research highlights: → Intensive land development as a result of the rapidly growing tourism industry in the 'Riviera Maya' region of the Yucatan Peninsula, Mexico is contaminating groundwater resources that discharge into Caribbean coastal ecosystems. → Passive sampling devices deployed in groundwater flowing through cave systems below two communities in the Riviera Maya accumulated: pharmaceuticals and personal care products originating from domestic sewage. → PAHs originating from runoff from highways and other impermeable surfaces; chlorophenoxy herbicides originating from pesticide applications to lawns and turf. → Prevention and mitigation measures are needed to ensure that expanding development does not impact the marine environment and human health in the region. - Contaminants accumulated in passive samplers deployed in flooded cave systems in the Yucatan Peninsula in Mexico indicate contamination by domestic sewage, runoff and applications of pesticides

  20. Contaminants in the coastal karst aquifer system along the Caribbean coast of the Yucatan Peninsula, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Metcalfe, Chris D., E-mail: cmetcalfe@trentu.ca [Worsfold Water Quality Centre, Trent University, Peterborough, ON, K9J 7B8 (Canada); Beddows, Patricia A. [Department of Earth and Planetary Sciences, Northwestern University, Evanston, IL (United States); Bouchot, Gerardo Gold [Departemento de Recursos del Mar, CINVESTAV Unidad Merida, Yucatan (Mexico); Metcalfe, Tracy L.; Li Hongxia [Worsfold Water Quality Centre, Trent University, Peterborough, ON, K9J 7B8 (Canada); Van Lavieren, Hanneke [UN University Institute for Water, Environment and Health (UNU-INWEH), Hamilton, ON (Canada)

    2011-04-15

    Intensive land development as a result of the rapidly growing tourism industry in the 'Riviera Maya' region of the Yucatan Peninsula, Mexico may result in contamination of groundwater resources that eventually discharge into Caribbean coastal ecosystems. We deployed two types of passive sampling devices into groundwater flowing through cave systems below two communities to evaluate concentrations of contaminants and to indicate the possible sources. Pharmaceuticals and personal care products accumulated in the samplers could only have originated from domestic sewage. PAHs indicated contamination by runoff from highways and other impermeable surfaces and chlorophenoxy herbicides accumulated in samplers deployed near a golf course indicated that pesticide applications to turf are a source of contamination. Prevention and mitigation measures are needed to ensure that expanding development does not impact the marine environment and human health, thus damaging the tourism-based economy of the region. - Research highlights: > Intensive land development as a result of the rapidly growing tourism industry in the 'Riviera Maya' region of the Yucatan Peninsula, Mexico is contaminating groundwater resources that discharge into Caribbean coastal ecosystems. > Passive sampling devices deployed in groundwater flowing through cave systems below two communities in the Riviera Maya accumulated: pharmaceuticals and personal care products originating from domestic sewage. > PAHs originating from runoff from highways and other impermeable surfaces; chlorophenoxy herbicides originating from pesticide applications to lawns and turf. > Prevention and mitigation measures are needed to ensure that expanding development does not impact the marine environment and human health in the region. - Contaminants accumulated in passive samplers deployed in flooded cave systems in the Yucatan Peninsula in Mexico indicate contamination by domestic sewage, runoff and applications of

  1. 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.

  2. The origin and disappearance of the late Pleistocene-early Holocene short-lived coastal wetlands along the Carmel coast, Israel

    Science.gov (United States)

    Sivan, Dorit; Greenbaum, Noam; Cohen-Seffer, Ronit; Sisma-Ventura, Guy; Almogi-Labin, Ahuva

    The formation of short-lived backswamps along the Carmel coast of Israel coincides with the rapid global sea-level rise during the late Pleistocene-early Holocene transition. The current study shows that the wetland phenomena originated around 10,000 yr ago and dried up shortly before the local Pre-Pottery Neolithic humans settled on the wetland dark clay sediments 9430 cal yr BP. Palaeontological and stable-isotope data were used in this study to elucidate previously published sedimentological reconstruction obtained from a core drilled into the western trough of the Carmel coastal plain. The water body contained typical brackish calcareous fauna, with variable numerical abundance and low species richness of ostracods and foraminifera. The δ 18O and δ 13C of the ostracod Cyprideis torosa show close similarity to the present Pleistocene coastal aquifer isotopic values. This study therefore concludes that the wetlands were shallow-water bodies fed by groundwater, with no evidence of sea-water mixing. It seems that they developed as the result of high groundwater levels, transportation of sediments landward, and deposition of sand bars at the paleo-river mouths. It is still not fully understood why these wetlands deteriorated abruptly and disappeared within less than 1000 yr.

  3. Incidence and distribution of heavy metals in soils of a Mediterranean coastal wetland (L'Albufera de Valencia, Spain)

    Science.gov (United States)

    Andreu, V.; Gimeno, E.; Fernandez-Despiau, E.; Pascual, J. A.

    2012-04-01

    One of the most important issues in environmental conservation nowadays is the preservation of wetlands, mainly the coastal ones. This becomes more imperative in the Mediterranean. These particular ecosystems have suffered during the last decades an increasing human pressure. This has been reflected through the intensification of agriculture and construction of infrastructures in their surroundings or even draining part of them. As a result, the density of population and its residues affect them in a first place. This work has been developed in the Natural Park of La Albufera (Valencia, Spain), which includes a coastal lagoon, marshlands, dunes and pinewoods, surrounded by rice fields in its not urbanized part. In spite of this great ecological value, it suffers impacts derived from the high human and industrial occupation, and of the hydrological contributions from the connected irrigation systems. In addition, this park is one of the most important wetland in Europe, included in the RAMSAR agreement, being a key point for migratory birds and contains in its area one of the most important zones on rice production in Europe. In the park area, 28 sampling zones were selected to determine the degree of heavy metals incidence in soils. Total concentrations of Cd, Co, Cr, Cu, Ni, Pb, and Zn were evaluated. Their distribution in the surficial and sub-surficial horizons was determined together with their spatial distribution, and the possible sources of contamination. Zn, Cr and Cu show the highest concentrations in all land uses and zones. Cr is the metal that present maximum concentration in the studied area (254.93 ppm), being almost the only metal studied that exceeds the limits established by the Spanish an EU legislation. Co and Ni shows a tendency to accumulate below the 30 cm depth, the other metal studied continue with the cumulative trend in surface horizons. All the studied metals, except Co have highly significant correlations with the available phosphorous

  4. Determining the spatial variability of wetland soil bulk density, organic matter, and the conversion factor between organic matter and organic carbon across coastal Louisiana, U.S.A.

    Science.gov (United States)

    Wang, Hongqing; Piazza, Sarai C.; Sharp, Leigh A.; Stagg, Camille L.; Couvillion, Brady R.; Steyer, Gregory D.; McGinnis, Thomas E.

    2016-01-01

    Soil bulk density (BD), soil organic matter (SOM) content, and a conversion factor between SOM and soil organic carbon (SOC) are often used in estimating SOC sequestration and storage. Spatial variability in BD, SOM, and the SOM–SOC conversion factor affects the ability to accurately estimate SOC sequestration, storage, and the benefits (e.g., land building area and vertical accretion) associated with wetland restoration efforts, such as marsh creation and sediment diversions. There are, however, only a few studies that have examined large-scale spatial variability in BD, SOM, and SOM–SOC conversion factors in coastal wetlands. In this study, soil cores, distributed across the entire coastal Louisiana (approximately 14,667 km2) were used to examine the regional-scale spatial variability in BD, SOM, and the SOM–SOC conversion factor. Soil cores for BD and SOM analyses were collected during 2006–09 from 331 spatially well-distributed sites in the Coastwide Reference Monitoring System network. Soil cores for the SOM–SOC conversion factor analysis were collected from 15 sites across coastal Louisiana during 2006–07. Results of a split-plot analysis of variance with incomplete block design indicated that BD and SOM varied significantly at a landscape level, defined by both hydrologic basins and vegetation types. Vertically, BD and SOM varied significantly among different vegetation types. The SOM–SOC conversion factor also varied significantly at the landscape level. This study provides critical information for the assessment of the role of coastal wetlands in large regional carbon budgets and the estimation of carbon credits from coastal restoration.

  5. Hydrological behavior of coastal lagoons associated to wetlands, an example from southernmost bahía Samborombón (Argentina).

    Science.gov (United States)

    Tejada Tejada, Macarena; Carol, Eleanora; Galliari, Julieta; Richiano, Sebastian

    2017-04-01

    Coastal wetlands are located at a critical interface between the terrestrial and marine environments and are ideally positioned to reduce impacts from land-based sources. At the southern region of Bahía Samborombón (Argentina) the wetlands includes several small coastal lagoons developed inside of a sandy spike. The main object of this work is to analyze the hydrological behavior of the lagoons evaluating their role in the maintenances of the wetland. In order to do this, satellite image analysis was performed to identify the marshy areas, drainage features, morphology and connections of the lagoons, both with the tidal flows from the Río de la Plata estuary and from the Argentine Sea. Field surveys were carried out in one of the lagoons to define their geological and geomorphological characteristics. After that, a monitoring network was designed for sampling the superficial and the underground water, additionally electrical conductivity and pH of the water were determined in situ. In all the water samples extracted the content of majority ions was determined by standard methods. Complementary, sedimentological and malacological aspects were observed at several stations in the lagoon. The obtained results allow us to recognize that the tidal flow that enters from the sea, at least in the studied lagoon, is the main hydrological sustenance of the wetland. This flow enters mainly using one tidal channel which connects (in a semi-permanent way) the sea with the lagoon during extraordinary tide and storm events. During low tide the lagoon loses connection and the drainage towards the sea is scarce. The tidal water that accumulates in the lagoon is subsequently evaporated causing an increase in the salinity of the surface water to values higher than the sea. Groundwater that accumulates through the infiltration of rainfall in the sandy sediments of the spike also discharges to the lagoon and supports the wetland surrounding the coastal lagoon. This flow, even when it

  6. Impacts of Climatic Hazards on the Small Wetland Ecosystems (ponds: Evidence from Some Selected Areas of Coastal Bangladesh

    Directory of Open Access Journals (Sweden)

    Lucy Faulkner

    2013-04-01

    Full Text Available Most climate related hazards in Bangladesh are linked to water. The climate vulnerable poor—the poorest and most marginalized communities living in remote villages along Bangladesh’s coastal zone that are vulnerable to climate change impacts and who possess low adaptive capacity are most affected by lack of access to safe water sources. Many climate vulnerable poor households depend on small isolated wetlands (ponds for daily drinking water needs and other domestic requirements, including cooking, bathing and washing. Similarly, the livelihoods of many of these households also depend on access to ponds due to activities of small-scale irrigation for rice farming, vegetable farming and home gardening. This is particularly true for those poorest and most marginalized communities living in Satkhira, one of the most vulnerable coastal districts in south-west Bangladesh. These households rely on pond water for vegetable farming and home gardening, especially during winter months. However, these pond water sources are highly vulnerable to climate change induced hazards, including flooding, drought, salinity intrusion, cyclone and storm surges, erratic rainfall patterns and variations in temperature. Cyclone Sidr and Cyclone Aila, which hit Bangladesh in 2007 and 2009 respectively, led to a significant number of such ponds being inundated with saline water. This impacted upon and resulted in wide scale implications for climate vulnerable poor households, including reduced availability of safe drinking water, and safe water for health and hygiene practices and livelihood activities. Those households living in remote areas and who are most affected by these climate impacts are dependent on water being supplied through aid, as well as travelling long distances to collect safe water for drinking purposes.

  7. Variation in tidal wetland plant diversity and composition within and among coastal estuaries: assessing the relative importance of environmental gradients

    Science.gov (United States)

    Question: Does wetland plant composition vary more by estuarine type (differentiated by the degree of riverine versus oceanic influence) or habitat type within estuaries (defined by US National Wetlands Inventory [NWI] marsh classes)? Location: Oregon estuaries: Netarts Bay, ...

  8. An inventory of wetland non-passerine birds along a southeastern Brazilian coastal area

    Directory of Open Access Journals (Sweden)

    D.C. Tavares

    2013-07-01

    Full Text Available This paper presents the list of non-passerine birds of coastal environments of the Quissama municipality, northern Rio de Janeiro State, southeastern Brazil. The surveys were conducted monthly between June 2011 and May 2012. Additional ad libitum observations were made between February 2008 and July 2012. We recorded 76 waterbird species of 15 families, of which Scolopacidae was the most representative, with 15 species. The high Nearctic shorebird species richness observed in coastal lagoons in Quissama (17 species is an evidence of the important role of the region as staging site for migratory birds at national level. Also, nine of the species recorded are threatened at regional and one is threatened at national level. It should be emphasized that three species considered locally extinct in the municipality of Rio de Janeiro, the most extensively surveyed area in the State, were recorded in the present study. Additionally, we present a high number of previously unrecorded species in northern Rio de Janeiro, and report the first documented record of Stercorarius pomarinus in Rio de Janeiro State. The region has a notorious Waterbird richness including endangered and migratory species, when compared to other coastal areas of the state.

  9. Export of Dissolved Lignin from Coastal Wetlands to the Louisiana Shelf

    Science.gov (United States)

    Bianchi, T. S.; Dimarco, S. F.; Smith, R. W.; Schreiner, K. M.

    2008-12-01

    Here we report on spatial and temporal changes in the concentration and composition of dissolved lignin- phenols in surface and bottom waters off the Louisiana coast (USA). Samples were collected at 7 stations on 2 cruises (April, and July, 2008) along a transect that spanned from inside Terrebonne Bay, Louisiana (12 m water depth) to the outer-most station on the inner Louisiana shelf (21 m water depth). The highest average concentration of dissolved organic carbon (DOC) and dissolved lignin, during both cruises, occurred at the interface between Terrebonne Bay and the inner shelf. Average DOC and dissolved lignin concentrations were significantly higher in April than in July across most stations. Based on hydrologic data, these higher concentrations clearly reflect a combined mixing of DOM from plume waters to the west and local marsh inputs. The cinnamyl/vanillyl (C/V) and syringyl/vanillyl (S/V) ratios indicated that the predominant source of lignin was from non-woody angiosperms - likely the dominant species of wetland plants Spartina alterniflora and S. patens (Spartina spp.) that border the entire bay. The high vanillic acid to vanillin (Ad/Al)v ratios for all stations were typical of that found near estuarine boundaries, where biologically- and photochemically-mediated lignin decay processes are important. This preliminary data indicates that wetlands provide another source of dissolved organic matter (DOM) to the Louisiana shelf that likely contributes to microbial food resources and hence hypoxia, especially in the context of the instability and extensive erosion of these marshes over the past ca. 50 years. This has important implications for the current management plan to reduce hypoxia in the GOM, particularly in those regions that extend west of the nutrient-rich highly productive near-field zones of Atchafalaya-Mississippi river plumes.

  10. Mercury Bioaccumulation in Tropical Mangrove Wetland Fishes: Evaluating Potential Risk to Coastal Wildlife.

    Science.gov (United States)

    Le, Dung Quang; Satyanarayana, Behara; Fui, Siau Yin; Shirai, Kotaro

    2018-03-26

    The present study, aimed at observing the total concentration of mercury (Hg) in edible finfish species with an implication to human health risk, was carried out from the Setiu mangrove wetlands on the east coast of Peninsular Malaysia. Out of 20 species observed, the highest Hg concentrations were found among carnivores-fish/invertebrate-feeders, followed by omnivores and carnivores-invertebrate-feeders, while the lowest concentrations in herbivores. The Hg concentrations varied widely with fish species and body size, from 0.12 to 2.10 mg/kg dry weight. A positive relationship between body weight and Hg concentration was observed in particular for Toxotes jaculatrix and Tetraodon nigroviridis. Besides the permissible range of Hg concentration up to 0.3 mg/kg (cf. United States Environmental Protection Agency (USEPA)) in majority of species, the carnivore feeders such as Acanthopagrus pacificus, Gerres filamentosus, and Caranx ignobilis have shown excess amounts (> 0.40 mg/kg flesh weight) that raising concerns over the consumption by local people. However, the weekly intake of mercury-estimated through the fish consumption in all three trophic levels-suggests that the present Hg concentrations are still within the range of Provisional Tolerable Weekly Intake (PTWI) reported by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Perhaps, a multi-species design for Hg monitoring at Setiu wetlands would be able to provide further insights into the level of toxicity transfer among other aquatic organisms and thereby a strong health risk assessment for the local communities.

  11. Use of N Natural Abundance and N Species Concentrations to Assess N-Cycling in Constructed and Natural Coastal Wetlands

    Directory of Open Access Journals (Sweden)

    C. Marjorie Aelion

    2010-01-01

    Full Text Available Natural abundance of N stable isotopes used in combination with concentrations may be useful indicators of N-cycling in wetlands. Concentrations and N signatures of NO3−, NH4+, and sediment organic nitrogen (SON were measured in two impacted coastal golf course retention ponds and two natural marshes. Limited NO3− was detected in natural site surface water or pore water, but both isotopic signature and concentrations of NO3− in surface water of impacted sites indicated anthropogenic inputs. In natural sites, NH4+ concentrations were greatest in deeper pore water and least in surface water, suggesting diffusion predominates. The natural sites had greater %SON, and N indicated that the natural sites also had greater NH4+ released from SON mineralization than impacted sites. In NO3−-limited systems, neither concentrations nor N natural abundance was able to provide information on N-cycling, while processes associated with NH4+ were better elucidated by using both concentrations and N natural abundance.

  12. Assessment of marine debris on the coastal wetland of Martil in the North-East of Morocco.

    Science.gov (United States)

    Alshawafi, Adel; Analla, Mohamed; Alwashali, Ebrahim; Aksissou, Mustapha

    2017-04-15

    Plastic waste at the coastal wetland in Martil beach in the North-East of Morocco is one of the problems that have appeared recently. This study aims to characterize the marine debris in the coast of Martil during the year 2015. The sampling is seasonally by type and size. The result shows, for the macro debris, the abundance of plastic (57%), lumber and paper (21.93%), cloth and fabric (7.8%), glass (5.42%), metal (4.40%), and rubber (3.4%). Micro debris is also present in the area in several forms such as wood, plants, and others by 75,63%. This was followed by the foam (26,95%), line (7,8%), and the film (1,23%). The seasonal variation (S1: January-March and S3: July to September) are the most polluted months of the year. The sources of marine debris are mainly tourism (beach users), land (run off), and commercial fishing in the four seasons of the year. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Contaminants in the coastal karst aquifer system along the Caribbean coast of the Yucatan Peninsula, Mexico.

    Science.gov (United States)

    Metcalfe, Chris D; Beddows, Patricia A; Bouchot, Gerardo Gold; Metcalfe, Tracy L; Li, Hongxia; Van Lavieren, Hanneke

    2011-04-01

    Intensive land development as a result of the rapidly growing tourism industry in the "Riviera Maya" region of the Yucatan Peninsula, Mexico may result in contamination of groundwater resources that eventually discharge into Caribbean coastal ecosystems. We deployed two types of passive sampling devices into groundwater flowing through cave systems below two communities to evaluate concentrations of contaminants and to indicate the possible sources. Pharmaceuticals and personal care products accumulated in the samplers could only have originated from domestic sewage. PAHs indicated contamination by runoff from highways and other impermeable surfaces and chlorophenoxy herbicides accumulated in samplers deployed near a golf course indicated that pesticide applications to turf are a source of contamination. Prevention and mitigation measures are needed to ensure that expanding development does not impact the marine environment and human health, thus damaging the tourism-based economy of the region. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Understanding Coastal Wetland Vulnerability to Sea-Level Rise Enhanced Inundation Using Real-Time Stage Monitoring, LiDAR, and Monte Carlo Simulation in Everglades National Park

    Science.gov (United States)

    Cooper, H.; Zhang, C.

    2017-12-01

    Coastal wetlands are one of the most productive ecological systems in the world, providing critical habitat area and valuable ecosystem services such as carbon sequestration. However, due to their location in low lying areas, coastal wetlands are particularly vulnerable to sea-level rise (SLR). Everglades National Park (ENP) encompasses the southern-most portion of the Greater Everglades Ecosystem, and is the largest subtropical wetland in the USA. Water depths have shown to have a significant relationship to vegetation community composition and organization while also playing a crucial role in vegetation health throughout the Everglades. Live plants play a vital role in maintaining soil structure (i.e. elevation), and decreases in vegetation health can cause peat collapse or wetland loss resulting in dramatic habitat, organic soil, and elevation loss posing concerns for Everglades management and restoration. One suspected mechanism for peat collapse is enhanced inundation due to SLR, thus mapping and modeling water depths is a critical component to understanding the potential impacts of future SLR. Previous research in the Everglades focused on a conventional Water Depth Model (WDM) approach where a Digital Elevation Model (DEM) is subtracted from a Water Table Elevation Model (WTEM). In this study, the conventional WDM approach is extended to a more rigorous WDM technique so that the accuracy and precision of the underlying data may be considered. Monte Carlo simulation is used to propagate probability distributions through our SLR depth model using our Random Forest-based LiDAR DEM, Empirical Bayesian Kriging-based WTEMs, uncertainties in vertical datums, soil accretion projections, and regional sea-level rise projections. Water depth maps were produced for the wet and dry seasons in April and October, which successfully revealed the potential spatial and temporal water depth variations due to future SLR. It is concluded that a more rigorous WDM technique helps

  15. The Gulf of Mexico Coastal Ocean Observing System: A Decade of Data Aggregation and Services.

    Science.gov (United States)

    Howard, M.; Gayanilo, F.; Kobara, S.; Baum, S. K.; Currier, R. D.; Stoessel, M. M.

    2016-02-01

    The Gulf of Mexico Coastal Ocean Observing System Regional Association (GCOOS-RA) celebrated its 10-year anniversary in 2015. GCOOS-RA is one of 11 RAs organized under the NOAA-led U.S. Integrated Ocean Observing System (IOOS) Program Office to aggregate regional data and make these data publicly-available in preferred forms and formats via standards-based web services. Initial development of GCOOS focused on building elements of the IOOS Data Management and Communications Plan which is a framework for end-to-end interoperability. These elements included: data discovery, catalog, metadata, online-browse, data access and transport. Initial data types aggregated included near real-time physical oceanographic, marine meteorological and satellite data. Our focus in the middle of the past decade was on the production of basic products such as maps of current oceanographic conditions and quasi-static datasets such as bathymetry and climatologies. In the latter part of the decade we incorporated historical physical oceanographic datasets and historical coastal and offshore water quality data into our holdings and added our first biological dataset. We also developed web environments and products to support Citizen Scientists and stakeholder groups such as recreational boaters. Current efforts are directed towards applying data quality assurance (testing and flagging) to non-federal data, data archiving at national repositories, serving and visualizing numerical model output, providing data services for glider operators, and supporting marine biodiversity observing networks. GCOOS Data Management works closely with the Gulf of Mexico Research Initiative Information and Data Cooperative and various groups involved with Gulf Restoration. GCOOS-RA has influenced attitudes and behaviors associated with good data stewardship and data management practices across the Gulf and will to continue to do so into the next decade.

  16. Short-term nitrogen additions can shift a coastal wetland from a sink to a source of N2O

    Science.gov (United States)

    Moseman-Valtierra, Serena; Gonzalez, Rosalinda; Kroeger, Kevin D.; Tang, Jianwu; Chao, Wei Chun; Crusius, John; Bratton, John F.; Green, Adrian; Shelton, James

    2011-01-01

    Coastal salt marshes sequester carbon at high rates relative to other ecosystems and emit relatively little methane particularly compared to freshwater wetlands. However, fluxes of all major greenhouse gases (N2O, CH4, and CO2) need to be quantified for accurate assessment of the climatic roles of these ecosystems. Anthropogenic nitrogen inputs (via run-off, atmospheric deposition, and wastewater) impact coastal marshes. To test the hypothesis that a pulse of nitrogen loading may increase greenhouse gas emissions from salt marsh sediments, we compared N2O, CH4 and respiratory CO2fluxes from nitrate-enriched plots in a Spartina patens marsh (receiving single additions of NaNO3 equivalent to 1.4 g N m−2) to those from control plots (receiving only artificial seawater solutions) in three short-term experiments (July 2009, April 2010, and June 2010). In July 2009, we also compared N2O and CH4 fluxes in both opaque and transparent chambers to test the influence of light on gas flux measurements. Background fluxes of N2O in July 2009 averaged −33 μmol N2O m−2 day−1. However, within 1 h of nutrient additions, N2O fluxes were significantly greater in plots receiving nitrate additions relative to controls in July 2009. Respiratory rates and CH4 fluxes were not significantly affected. N2O fluxes were significantly higher in dark than in transparent chambers, averaging 108 and 42 μmol N2O m−2 day−1 respectively. After 2 days, when nutrient concentrations returned to background levels, none of the greenhouse gas fluxes differed from controls. In April 2010, N2O and CH4 fluxes were not significantly affected by nitrate, possibly due to higher nitrogen demands by growing S. patens plants, but in June 2010 trends of higher N2O fluxes were again found among nitrate-enriched plots, indicating that responses to nutrient pulses may be strongest during the summer. In terms of carbon equivalents, the highest average N2O and CH4 fluxes observed, exceeded half

  17. The magnitude and origin of groundwater discharge to eastern U.S. and Gulf of Mexico coastal waters

    Science.gov (United States)

    Befus, Kevin; Kroeger, Kevin D.; Smith, Christopher G.; Swarzenski, Peter W.

    2017-01-01

    Fresh groundwater discharge to coastal environments contributes to the physical and chemical conditions of coastal waters, but the role of coastal groundwater at regional to continental scales remains poorly defined due to diverse hydrologic conditions and the difficulty of tracking coastal groundwater flow paths through heterogeneous subsurface materials. We use three-dimensional groundwater flow models for the first time to calculate the magnitude and source areas of groundwater discharge from unconfined aquifers to coastal waterbodies along the entire eastern U.S. We find that 27.1 km3/yr (22.8–30.5 km3/yr) of groundwater directly enters eastern U.S. and Gulf of Mexico coastal waters. The contributing recharge areas comprised ~175,000 km2 of U.S. land area, extending several kilometers inland. This result provides new information on the land area that can supply natural and anthropogenic constituents to coastal waters via groundwater discharge, thereby defining the subterranean domain potentially affecting coastal chemical budgets and ecosystem processes.

  18. Treatment Wetlands

    OpenAIRE

    Dotro, Gabriela; Langergraber, Günter; Molle, Pascal; Nivala, Jaime; Puigagut, Jaume; Stein, Otto; Von Sperling, Marcos

    2017-01-01

    Overview of Treatment Wetlands; Fundamentals of Treatment Wetlands; Horizontal Flow Wetlands; Vertical Flow Wetlands; French Vertical Flow Wetlands; Intensified and Modified Wetlands; Free Water Surface Wetlands; Other Applications; Additional Aspects.

  19. Phenotypic variation in dorsal fin morphology of coastal bottlenose dolphins (Tursiops truncatus off Mexico

    Directory of Open Access Journals (Sweden)

    Eduardo Morteo

    2017-06-01

    Full Text Available Geographic variation in external morphology is thought to reflect an interplay between genotype and the environment. Morphological variation has been well-described for a number of cetacean species, including the bottlenose dolphin (Tursiops truncatus. In this study we analyzed dorsal fin morphometric variation in coastal bottlenose dolphins to search for geographic patterns at different spatial scales. A total of 533 dorsal fin images from 19 available photo-identification catalogs across the three Mexican oceanic regions (Pacific Ocean n = 6, Gulf of California n = 6 and, Gulf of Mexico n = 7 were used in the analysis. Eleven fin shape measurements were analyzed to evaluate fin polymorphism through multivariate tests. Principal Component Analysis on log-transformed standardized ratios explained 94% of the variance. Canonical Discriminant Function Analysis on factor scores showed separation among most study areas (p < 0.05 with exception of the Gulf of Mexico where a strong morphometric cline was found. Possible explanations for the observed differences are related to environmental, biological and evolutionary processes. Shape distinction between dorsal fins from the Pacific and those from the Gulf of California were consistent with previously reported differences in skull morphometrics and genetics. Although the functional advantages of dorsal fin shape remains to be assessed, it is not unlikely that over a wide range of environments, fin shape may represent a trade-off among thermoregulatory capacity, hydrodynamic performance and the swimming/hunting behavior of the species.

  20. Feeding ecology of juvenile marine fish in a shallow coastal lagoon of southeastern Mexico

    Directory of Open Access Journals (Sweden)

    Daniel Arceo-Carranza

    2015-09-01

    Full Text Available Many species of marine fish use coastal lagoons during early stages of their life cycles due to the protection provided by their turbid waters and complex structure of the environment, such as mangroves and mudflats, and the availability of food derived from the high productivity of these sites. In this study, we analyzed the diet of six species of juvenile marine fishes that use a karstic lagoon system in the northwest portion of the Yucatan Peninsula, Mexico. Through stomach contents analysis we determined the trophic differences among Caranx latus, Oligoplites saurus, Trachinotus falcatus, Synodus foetens, Lutjanus griseus, and Strongylura notata. C. latus, O. saurus, S. foetens, and S. notate, which are ichthyophagous species (>80% by number. L. griseus feeds mainly on crustaceans (>55% and fish (35%, while T. falcatus feeds on mollusks (>50% bivalves, >35% gastropods. The analysis of similarities (ANOSIM showed differences in the diet of all species. Cluster analysis, based on the Bray-Curtis similarity matrix revealed three groups; one characterized by the ichthyophagous guild (S. notata, S. foetens, C. latus, and O. saurus, other group formed by the crustacean consumers (L. griseus, and the third, composed by the mollusk feeder (T. falcatus. Species of the ichthyophagous guild showed overlap in their diets, which under conditions of low prey abundance may trigger competition, hence affecting juvenile stages of these marine species that use coastal lagoons to feed and grow.

  1. Effects of nutrient loading on the carbon balance of coastal wetland sediments

    Science.gov (United States)

    Morris, J.T.; Bradley, P.M.

    1999-01-01

    Results of a 12-yr study in an oligotrophic South Carolina salt marsh demonstrate that soil respiration increased by 795 g C m-2 yr-1 and that carbon inventories decreased in sediments fertilized with nitrogen and phosphorus. Fertilized plots became net sources of carbon to the atmosphere, and sediment respiration continues in these plots at an accelerated pace. After 12 yr of treatment, soil macroorganic matter in the top 5 cm of sediment was 475 g C m-2 lower in fertilized plots than in controls, which is equivalent to a constant loss rate of 40 g C m-2 yr-1. It is not known whether soil carbon in fertilized plots has reached a new equilibrium or continues to decline. The increase in soil respiration in the fertilized plots was far greater than the loss of sediment organic matter, which indicates that the increase in soil respiration was largely due to an increase in primary production. Sediment respiration in laboratory incubations also demonstrated positive effects of nutrients. Thus, the results indicate that increased nutrient loading of oligotrophic wetlands can lead to an increased rate of sediment carbon turnover and a net loss of carbon from sediments.

  2. Land and Water Grabbing in an East African Coastal Wetland: The Case of the Tana Delta

    Directory of Open Access Journals (Sweden)

    Stéphanie Duvail

    2012-06-01

    Full Text Available The delta of the Tana river in Kenya, an important wetland in Eastern Africa, is at a major turning point. Key decisions regarding its future are on the verge of being made, some of which may dramatically alter its characteristics. At present, in a landscape that is a mosaic of floodplains and forests of high biodiversity, small-scale farming, fishing and livestock-keeping are the main activities practised by the local communities, all relying on the occurrence of floods in November and May. Private investors with the backing of governmental bodies or parastatals, including the river basin authority, have planned the conversion of the lower Tana into irrigated sugar cane and Jatropha curcas plantations for biofuel production. In this paper, we discuss the land and water grabbing aspect of this new biofuel production trend, 'grabbing' being defined as cases of land acquisition or water abstraction where established user-rights and public interests are disregarded. We focus on two case studies: a planned large-scale sugar cane plantation in the central floodplain and a large-scale Jatropha curcas plantation on the floodplain terraces. We demonstrate through a water budget analysis that their potential impacts on the water balance and quality, on the environment of the Tana delta and therefore on the flood-dependent livelihoods have not been adequately addressed in the Environmental Impact Assessment documents.

  3. Towards Defining the Ecological Niches of Novel Coastal Gulf of Mexico Bacterial Isolates

    Science.gov (United States)

    Henson, M. W.; Thrash, C.; Nall, E.

    2016-02-01

    The study of microbial contributions to biogeochemistry is critical to understanding the cycles of fundamental compounds and gain predictive capabilities in a changing environment. Such study requires observation of microbial communities and genetics in nature, coupled with experimental testing of hypotheses both in situ and in laboratory settings. This study combines dilution-to-extinction based high-throughput culturing (HTC) with cultivation-independent and geochemical measurements to define potential ecological niches of novel bacterial isolates from the coastal northern Gulf of Mexico (cnGOM). Here we report findings from the first of a three-year project. In total, 43 cultures from seven HTC experiments were capable of being repeatedly transferred. Sanger sequencing of the 16S rRNA gene identified these isolates as belonging to the phyla Gammaproteobacteria, Alphaproteobacteria, Actinobacteria, and Betaproteobacteria. Eight are being genome sequenced, with two selected for further physiological characterization due to their phylogenic novelty and potential ecological significance. Strain LSUCC101 likely represents a novel family of Gammaproteobacteria (best blast hit to a cultured representative showed 91% sequence identity) and strain LSUCC96 belongs to the OM252 clade, with the Hawaiian isolate HIMB30 as its closest relative. Both are small (0.3-0.5 µm) cocci. The environmental importance of both LSUCC101 and LSUCC96 was illustrated by their presence within the top 30 OTU0.03 of cnGOM 16S rRNA gene datasets as well as within clone libraries from coastal regions around the world. Ongoing work is determining growth efficiencies, substrate utilization profiles, and metabolic potential to elucidate the roles of these organisms in the cnGOM. Comparative genomics will examine the evolutionary divergence of these organisms from their closest neighbors, and metagenomic recruitment to genomes will help identify strain-based variation from different coastal regions.

  4. Methane fluxes from tropical coastal lagoons surrounded by mangroves, Yucatán, Mexico

    Science.gov (United States)

    Chuang, P.-C.; Young, M. B.; Dale, A. W.; Miller, L. G.; Herrera-Silveira, J. A.; Paytan, A.

    2017-05-01

    Methane concentrations in the water column and emissions to the atmosphere were determined for three tropical coastal lagoons surrounded by mangrove forests on the Yucatán Peninsula, Mexico. Surface water dissolved methane was sampled at different seasons over a period of 2 years in areas representing a wide range of salinities and anthropogenic impacts. The highest surface water methane concentrations (up to 8378 nM) were measured in a polluted canal associated with Terminos Lagoon. In Chelem Lagoon, methane concentrations were typically lower, except in the polluted harbor area (1796 nM). In the relatively pristine Celestún Lagoon, surface water methane concentrations ranged from 41 to 2551 nM. Methane concentrations were negatively correlated with salinity in Celestún, while in Chelem and Terminos high methane concentrations were associated with areas of known pollution inputs, irrespective of salinity. The diffusive methane flux from surface lagoon water to the atmosphere ranged from 0.0023 to 15 mmol CH4 m-2 d-1. Flux chamber measurements revealed that direct methane release as ebullition was up to 3 orders of magnitude greater than measured diffusive flux. Coastal mangrove lagoons may therefore be an important natural source of methane to the atmosphere despite their relatively high salinity. Pollution inputs are likely to substantially enhance this flux. Additional statistically rigorous data collected globally are needed to better consider methane fluxes from mangrove-surrounded coastal areas in response to sea level changes and anthropogenic pollution in order to refine projections of future atmospheric methane budgets.

  5. A Carbon Monitoring System Approach to US Coastal Wetland Carbon Fluxes: Progress Towards a Tier II Accounting Method with Uncertainty Quantification

    Science.gov (United States)

    Windham-Myers, L.; Holmquist, J. R.; Bergamaschi, B. A.; Byrd, K. B.; Callaway, J.; Crooks, S.; Drexler, J. Z.; Feagin, R. A.; Ferner, M. C.; Gonneea, M. E.; Kroeger, K. D.; Megonigal, P.; Morris, J. T.; Schile, L. M.; Simard, M.; Sutton-Grier, A.; Takekawa, J.; Troxler, T.; Weller, D.; Woo, I.

    2015-12-01

    Despite their high rates of long-term carbon (C) sequestration when compared to upland ecosystems, coastal C accounting is only recently receiving the attention of policy makers and carbon markets. Assessing accuracy and uncertainty in net C flux estimates requires both direct and derived measurements based on both short and long term dynamics in key drivers, particularly soil accretion rates and soil organic content. We are testing the ability of remote sensing products and national scale datasets to estimate biomass and soil stocks and fluxes over a wide range of spatial and temporal scales. For example, the 2013 Wetlands Supplement to the 2006 IPCC GHG national inventory reporting guidelines requests information on development of Tier I-III reporting, which express increasing levels of detail. We report progress toward development of a Carbon Monitoring System for "blue carbon" that may be useful for IPCC reporting guidelines at Tier II levels. Our project uses a current dataset of publically available and contributed field-based measurements to validate models of changing soil C stocks, across a broad range of U.S. tidal wetland types and landuse conversions. Additionally, development of biomass algorithms for both radar and spectral datasets will be tested and used to determine the "price of precision" of different satellite products. We discuss progress in calculating Tier II estimates focusing on variation introduced by the different input datasets. These include the USFWS National Wetlands Inventory, NOAA Coastal Change Analysis Program, and combinations to calculate tidal wetland area. We also assess the use of different attributes and depths from the USDA-SSURGO database to map soil C density. Finally, we examine the relative benefit of radar, spectral and hybrid approaches to biomass mapping in tidal marshes and mangroves. While the US currently plans to report GHG emissions at a Tier I level, we argue that a Tier II analysis is possible due to national

  6. Ecological, biogeochemical and salinity changes in coastal lakes and wetlands over the last 200 years

    Science.gov (United States)

    Roberts, Lucy; Holmes, Jonathan; Horne, David

    2016-04-01

    Shallow lakes provide extensive ecosystem services and are ecologically important aquatic resources supporting a diverse flora and fauna. In marginal-marine areas, where such lakes are subjected to the multiple pressures of coastal erosion, sea level rise, increasing sea surface temperature and increasing frequency and intensity of storm surges, environments are complex and unstable. They are characterised by physico-chemical variations due to climatic (precipitation/evaporation cycles) and dynamic factors (tides, currents, freshwater drainage and sea level changes). Combined with human activity in the catchment these processes can alter the salinity, habitat and ecology of coastal fresh- to brackish water ecosystems. In this study the chemical and biological stability of coastal lakes forming the Upper Thurne catchment in the NE of the Norfolk Broads, East Anglia, UK are seriously threatened by long-term changes in salinity resulting from storm surges, complex hydrogeology and anthropogenic activity in the catchment. Future management decisions depend on a sound understanding of the potential ecological impacts, but such understanding is limited by short-term observations and measurements. This research uses palaeolimnological approaches, which can be validated and calibrated with historical records, to reconstruct changes in the aquatic environment on a longer time scale than can be achieved by observations alone. Here, salinity is quantitatively reconstructed using the trace-element geochemistry (Sr/Ca and Mg/Ca) of low Mg-calcite shells of Ostracoda (microscopic bivalved crustaceans) and macrophyte and macroinvertebrate macrofossil remains are used as a proxy to assess ecological change in response to variations in salinity. δ13C values of Cladocera (which are potentially outcompeted by the mysid Neomysis integer with increasing salinity and eutrophication) can be used to reconstruct carbon cycling and energy pathways in lake food webs, which alongside

  7. Mercury adsorption in the Mississippi River deltaic plain freshwater marsh soil of Louisiana Gulf coastal wetlands.

    Science.gov (United States)

    Park, Jong-Hwan; Wang, Jim J; Xiao, Ran; Pensky, Scott M; Kongchum, Manoch; DeLaune, Ronald D; Seo, Dong-Cheol

    2018-03-01

    Mercury adsorption characteristics of Mississippi River deltaic plain (MRDP) freshwater marsh soil in the Louisiana Gulf coast were evaluated under various conditions. Mercury adsorption was well described by pseudo-second order and Langmuir isotherm models with maximum adsorption capacity of 39.8 mg g -1 . Additional fitting of intraparticle model showed that mercury in the MRDP freshwater marsh soil was controlled by both external surface adsorption and intraparticle diffusion. The partition of adsorbed mercury (mg g -1 ) revealed that mercury was primarily adsorbed into organic-bond fraction (12.09) and soluble/exchangeable fraction (10.85), which accounted for 63.5% of the total adsorption, followed by manganese oxide-bound (7.50), easily mobilizable carbonate-bound (4.53), amorphous iron oxide-bound (0.55), crystalline Fe oxide-bound (0.41), and residual fraction (0.16). Mercury adsorption capacity was generally elevated along with increasing solution pH even though dominant species of mercury were non-ionic HgCl 2 , HgClOH and Hg(OH) 2  at between pH 3 and 9. In addition, increasing background NaCl concentration and the presence of humic acid decreased mercury adsorption, whereas the presence of phosphate, sulfate and nitrate enhanced mercury adsorption. Mercury adsorption in the MRDP freshwater marsh soil was reduced by the presence of Pb, Cu, Cd and Zn with Pb showing the greatest competitive adsorption. Overall the adsorption capacity of mercury in the MRDP freshwater marsh soil was found to be significantly influenced by potential environmental changes, and such factors should be considered in order to manage the risks associated with mercury in this MRDP wetland for responding to future climate change scenarios. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Effects of Hydrologic Restoration on the Residence Times and Water Quality of a Coastal Wetland in the Florida Everglades

    Science.gov (United States)

    Sandoval, E.; Price, R. M.; Melesse, A. M.; Whitman, D.

    2013-05-01

    The Everglades, located in southern Florida, is a dominantly freshwater coastal wetland ecosystem that has experienced many alterations and changes led by urbanization and water management practices with most cases resulting in decreased water flow across the system. The Comprehensive Everglades Restoration Plan, passed in 2000, has the final goal of restoring natural flow and clean water to the Everglades while also balancing flood control and water supply needs of the south Florida population with approximately 60 projects to be constructed and completed in the following 30 years. One way to assess the success of restoration projects is to observe long-term hydrological and geochemical changes as the projects undergo completion. The purpose of this research was to investigate the effects of restoration on the water balance, flushing time, and water chemistry of Taylor Slough; one of the main natural waterways located within the coastal Everglades. A water balance equation was used to solve for groundwater-surface water exchange. The major parameters for the water balance equation (precipitation, evapotranspiration (ET), surface water storage, inflow and outflow) were obtained from the U.S. Geological Survey and Everglades National Park databases via the Everglades Depth Estimation Network (EDEN). Watershed flushing times were estimated as the surface water volume divided by the total outputs from the watershed. Both the water balance equation and water flushing time were calculated on a monthly time step from 2001 - 2011. Water chemistry of major ions and Total Nitrogen (TN) and Total Phosphorus (TP) was analyzed on water samples, 3-day composites collected every 18 hours from 2008 - 2012, and correlated with water flushing times. Stable isotopes of oxygen and hydrogen of water samples were obtained to support the dominant inputs of water into Taylor Slough as identified by the water budget equation. Results for flushing times varied between 3 and 78 days, with

  9. Phosphorus sorption-desorption and effects of temperature, pH and salinity on phosphorus sorption in marsh soils from coastal wetlands with different flooding conditions.

    Science.gov (United States)

    Bai, Junhong; Ye, Xiaofei; Jia, Jia; Zhang, Guangliang; Zhao, Qingqing; Cui, Baoshan; Liu, Xinhui

    2017-12-01

    Wetland soils act as a sink or source of phosphorus (P) to the overlaying water due to phosphorus sorption-desorption processes. Litter information is available on sorption and desorption behaviors of phosphorus in coastal wetlands with different flooding conditions. Laboratory experiments were conducted to investigate phosphorus sorption-desorption processes, fractions of adsorbed phosphorus, and the effects of salinity, pH and temperature on phosphorus sorption on soils in tidal-flooding wetlands (TW), freshwater-flooding wetlands (FW) and seasonal-flooding wetlands (SW) in the Yellow River Delta. Our results showed that the freshly adsorbed phosphorus dominantly exists in Occluded-P and Fe/AlP and their percentages increased with increasing phosphorus adsorbed. Phosphorus sorption isotherms could be better described by the modified Langmuir model than by the modified Freundlich model. A binomial equation could be properly used to describe the effects of salinity, pH, and temperature on phosphorus sorption. Phosphorus sorption generally increased with increasing salinity, pH, and temperature at lower ranges, while decreased in excess of some threshold values. The maximum phosphorus sorption capacity (Q max ) was larger for FW soils (256 mg/kg) compared with TW (218 mg/kg) and SW soils (235 mg/kg) (p < 0.05). The percentage of phosphorus desorption (P des ) in the FW soils (7.5-63.5%) was much lower than those in TW (27.7-124.9%) and SW soils (19.2-108.5%). The initial soil organic matter, pH and the exchangeable Al, Fe and Cd contents were important factors influencing P sorption and desorption. The findings of this study indicate that freshwater restoration can contribute to controlling the eutrophication status of water bodies through increasing P sorption. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Challenges and opportunities for implementing sustainable energy strategies in coastal communities of Baja California Sur, Mexico

    Science.gov (United States)

    Etcheverry, Jose R.

    This dissertation explores the potential of renewable energy and efficiency strategies to solve the energy challenges faced by the people living in the biosphere reserve of El Vizcaino, which is located in the North Pacific region of the Mexican state of Baja California Sur. This research setting provides a practical analytical milieu to understand better the multiple problems faced by practitioners and agencies trying to implement sustainable energy solutions in Mexico. The thesis starts with a literature review (chapter two) that examines accumulated international experience regarding the development of renewable energy projects as a prelude to identifying the most salient implementation barriers impeding this type of initiatives. Two particularly salient findings from the literature review include the importance of considering gender issues in energy analysis and the value of using participatory research methods. These findings informed fieldwork design and the analytical framework of the dissertation. Chapter three surveys electricity generation as well as residential and commercial electricity use in nine coastal communities located in El Vizcaino. Chapter three summarizes the fieldwork methodology used, which relies on a mix of qualitative and quantitative research methods that aim at enabling a gender-disaggregated analysis to describe more accurately local energy uses, needs, and barriers. Chapter four describes the current plans of the state government, which are focused in expanding one of the state's diesel-powered electricity grids to El Vizcaino. The Chapter also examines the potential for replacing diesel generators with a combination of renewable energy systems and efficiency measures in the coastal communities sampled. Chapter five analyzes strategies to enable the implementation of sustainable energy approaches in El Vizcaino. Chapter five highlights several international examples that could be useful to inform organizational changes at the federal

  11. Fish functional groups in a tropical wetland of the Yucatan Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Fernando Córdova-Tapia

    Full Text Available ABSTRACT The characterization of species' functional traits is a major step in the understanding and description of communities in natural habitats. The classification of species into functional groups is a useful tool to identify redundancy and uniqueness. We studied the fish community of a pristine freshwater wetland in the Sian Ka'an Biosphere Reserve by analysing two multidimensional functions: food acquisition and locomotion. We investigated changes in the functional group structure between habitats (permanent and temporary pools and seasons (dry and wet. Six functional groups with different ecological characteristics were detected, two of which had high functional redundancy and three of them were represented by single species with unique ecological functions. In permanent pools during the dry season, functional group richness and diversity were lower, while evenness was higher. During the wet season, all functional groups were detected and similar functional group structure was found between habitats. These results suggest an effect of environmental filtering during the dry season and niche complementarity during the wet season.

  12. Modeling soil parameters using hyperspectral image reflectance in subtropical coastal wetlands

    Science.gov (United States)

    Anne, Naveen J. P.; Abd-Elrahman, Amr H.; Lewis, David B.; Hewitt, Nicole A.

    2014-12-01

    Developing spectral models of soil properties is an important frontier in remote sensing and soil science. Several studies have focused on modeling soil properties such as total pools of soil organic matter and carbon in bare soils. We extended this effort to model soil parameters in areas densely covered with coastal vegetation. Moreover, we investigated soil properties indicative of soil functions such as nutrient and organic matter turnover and storage. These properties include the partitioning of mineral and organic soil between particulate (>53 μm) and fine size classes, and the partitioning of soil carbon and nitrogen pools between stable and labile fractions. Soil samples were obtained from Avicennia germinans mangrove forest and Juncus roemerianus salt marsh plots on the west coast of central Florida. Spectra corresponding to field plot locations from Hyperion hyperspectral image were extracted and analyzed. The spectral information was regressed against the soil variables to determine the best single bands and optimal band combinations for the simple ratio (SR) and normalized difference index (NDI) indices. The regression analysis yielded levels of correlation for soil variables with R2 values ranging from 0.21 to 0.47 for best individual bands, 0.28 to 0.81 for two-band indices, and 0.53 to 0.96 for partial least-squares (PLS) regressions for the Hyperion image data. Spectral models using Hyperion data adequately (RPD > 1.4) predicted particulate organic matter (POM), silt + clay, labile carbon (C), and labile nitrogen (N) (where RPD = ratio of standard deviation to root mean square error of cross-validation [RMSECV]). The SR (0.53 μm, 2.11 μm) model of labile N with R2 = 0.81, RMSECV= 0.28, and RPD = 1.94 produced the best results in this study. Our results provide optimism that remote-sensing spectral models can successfully predict soil properties indicative of ecosystem nutrient and organic matter turnover and storage, and do so in areas with dense

  13. Sedimentary and Vegetative Impacts of Hurricane Irma to Coastal Wetland Ecosystems across Southwest Florida

    Science.gov (United States)

    Moyer, R. P.; Khan, N.; Radabaugh, K.; Engelhart, S. E.; Smoak, J. M.; Horton, B.; Rosenheim, B. E.; Kemp, A.; Chappel, A. R.; Schafer, C.; Jacobs, J. A.; Dontis, E. E.; Lynch, J.; Joyse, K.; Walker, J. S.; Halavik, B. T.; Bownik, M.

    2017-12-01

    Since 2014, our collaborative group has been working in coastal marshes and mangroves across Southwest Florida, including Tampa Bay, Charlotte Harbor, Ten Thousand Islands, Biscayne Bay, and the lower Florida Keys. All existing field sites were located within 50 km of Hurricane Irma's eye path, with a few sites in the Lower Florida Keys and Naples/Ten Thousand Islands region suffering direct eyewall hits. As a result, we have been conducting storm-impact and damage assessments at these locations with the primary goal of understanding how major hurricanes contribute to and/or modify the sedimentary record of mangroves and salt marshes. We have also assessed changes to the vegetative structure of the mangrove forests at each site. Preliminary findings indicate a reduction in mangrove canopy cover from 70-90% pre-storm, to 30-50% post-Irma, and a reduction in tree height of approximately 1.2 m. Sedimentary deposits consisting of fine carbonate mud up to 12 cm thick were imported into the mangroves of the lower Florida Keys, Biscayne Bay, and the Ten Thousand Islands. Import of siliciclastic mud up to 5 cm thick was observed in Charlotte Harbor. In addition to fine mud, all sites had imported tidal wrack consisting of a mixed seagrass and mangrove leaf litter, with some deposits as thick as 6 cm. In areas with newly opened canopy, a microbial layer was coating the surface of the imported wrack layer. Overwash and shoreline erosion were also documented at two sites in the lower Keys and Biscayne Bay, and will be monitored for change and recovery over the next few years. Because active research was being conducted, a wealth of pre-storm data exists, thus these locations are uniquely positioned to quantify hurricane impacts to the sedimentary record and standing biomass across a wide geographic area. Due to changes in intensity along the storm path, direct comparisons of damage metrics can be made to environmental setting, wind speed, storm surge, and distance to eyewall.

  14. Methane and sulfate dynamics in sediments from mangrove-dominated tropical coastal lagoons, Yucatan, Mexico

    Science.gov (United States)

    Chuang, P. C.; Young, Megan B.; Dale, Andrew W.; Miller, Laurence G.; Herrera-Silveira, Jorge A.; Paytan, Adina

    2016-01-01

    Porewater profiles in sediment cores from mangrove-dominated coastal lagoons (Celestún and Chelem) on the Yucatán Peninsula, Mexico, reveal the widespread coexistence of dissolved methane and sulfate. This observation is interesting since dissolved methane in porewaters is typically oxidized anaerobically by sulfate. To explain the observations we used a numerical transport-reaction model that was constrained by the field observations. The model suggests that methane in the upper sediments is produced in the sulfate reduction zone at rates ranging between 0.012 and 31 mmol m−2 d−1, concurrent with sulfate reduction rates between 1.1 and 24 mmol SO42− m−2 d−1. These processes are supported by high organic matter content in the sediment and the use of non-competitive substrates by methanogenic microorganisms. Indeed sediment slurry incubation experiments show that non-competitive substrates such as trimethylamine (TMA) and methanol can be utilized for microbial methanogenesis at the study sites. The model also indicates that a significant fraction of methane is transported to the sulfate reduction zone from deeper zones within the sedimentary column by rising bubbles and gas dissolution. The shallow depths of methane production and the fast rising methane gas bubbles reduce the likelihood for oxidation, thereby allowing a large fraction of the methane formed in the sediments to escape to the overlying water column.

  15. Phosphorus Fluxes from Three Coastal Watersheds under Varied Agriculture Intensities to the Northern Gulf of Mexico

    Directory of Open Access Journals (Sweden)

    Songjie He

    2018-06-01

    Full Text Available This study aims to evaluate recent total phosphorus (TP and dissolved inorganic phosphorus (DIP transport from three coastal rivers—the Calcasieu, Mermentau, and Vermilion Rivers—that drain watersheds with varied agriculture intensities (21%, 67%, and 61%, respectively into the northern Gulf of Mexico, one of the world’s largest summer hypoxic zones. The study also examined the spatial trends of TP and DIP from freshwater to saltwater along an 88-km estuarine reach with salinity increasing from 0.02 to 29.50. The results showed that from 1990–2009 to 2010–2017, the TP fluxes for one of the agriculture-intensive rivers increased while no significant change was found for the other two rivers. Change in river discharge was the main reason for this TP flux trend. The two more agriculture-intensive river basins showed consistently higher TP and DIP concentrations and fluxes, as well as higher DIP:TP ratios than the river draining less agriculture-intensive land, confirming the strong effect of land uses on phosphorus input and speciation. Longitudinal profiles of DIP along the salinity gradient of the estuarine reach displayed characteristic input behavior. Desorption of DIP from suspended solids and river bed sediments, urban inputs, as well as stronger calcium carbonate and phosphorus co-precipitation at the marine endmember could be the reasons for such mixing dynamics.

  16. Reactive silica fractions in coastal lagoon sediments from the northern Gulf of Mexico

    Science.gov (United States)

    Krause, Jeffrey W.; Darrow, Elizabeth S.; Pickering, Rebecca A.; Carmichael, Ruth H.; Larson, Ashley M.; Basaldua, Jose L.

    2017-12-01

    Continental-margin sediments account for 50% of the oceanic biogenic silica burial despite covering Gulf of Mexico (nGoM), we measured sediment biogenic silica at sites removed from major freshwater discharge sources using the traditional method and a method that has been modified for deltaic systems to quantify other reactive silica pools, specifically those involved in the process of reverse weathering. The magnitude of authigenically-altered biogenic silica during our study was significant and represented, on average, 33% of the total sediment biogenic silica among core depths and sites. Additionally, there was a significant relationship between the degree to which the biogenic silica pool was authigenically altered and the source of the sediment organic matter, with lower modification in sediments corresponding with higher terrestrial organic matter. We observed no positive correlation between the magnitude of authigenic modification and sediment clay content. Thus, our findings suggest that these processes may occur within a variety of sediment compositions and add to a growing body of evidence suggesting that reverse weathering of silica in coastal systems is a significant pathway in the global silica budget.

  17. Fringe wetlands

    International Nuclear Information System (INIS)

    Lugo, A.E.

    1990-01-01

    Fringe wetlands are characterized by the dominance of few species, a clear species zonation, synchrony of ecological processes with episodic events, and simplicity in the structure of vegetation. The structure and ecosystem dynamics of fringe forested wetlands are presented with emphasis on saltwater wetlands because they have been studied more than freshwater ones. The study areas were Caribbean and Florida mangroves. Fringe wetlands are found on the water edge of oceans, inland estuaries, and lakes. Water motion in the fringe is bi-directional and perpendicular to the forest and due mostly to tidal energy in oceanic and estuarine fringes. in lakes, water moves in and out of the fringe under the influence of wind, waves, or seiches. some fringe forests are occasionally flushed by terrestrial runoff or aquifer discharge. In contrast, fringe forests located on small offshore islands or steep coastal shroes are isolated from terrestrial runoff or aquifer discharge, and their hydroperiod is controlled by tides and waves only. Literature reviews suggest that ecosystem parameters such as vegetation structure, tree growth, primary productivity, and organic matter in sediments respond proportionally to hydrologic energy. Human activity that impacts on fringe forested wetlands include harvesting of trees, oil pollution and eutrophication. 72 refs., 12 figs., 9 tabs

  18. Mexico.

    Science.gov (United States)

    Semaan, Leslie

    The text explores Mexico's history, geography, art, religion, and lifestyles in the context of its complex economy. The text focuses on Mexico's economy and reasons for its current situation. Part I of this teaching unit includes: Teacher Overview, Why Study Mexico, Mexico Fact Sheet, Map of Mexico, the Land and Climate, History, Government,…

  19. Hurricane impacts on coastal wetlands: a half-century record of storm-generated features from southern Louisiana

    Science.gov (United States)

    Morton, Robert A.; Barras, John A.

    2011-01-01

    Temporally and spatially repeated patterns of wetland erosion, deformation, and deposition are observed on remotely sensed images and in the field after hurricanes cross the coast of Louisiana. The diagnostic morphological wetland features are products of the coupling of high-velocity wind and storm-surge water and their interaction with the underlying, variably resistant, wetland vegetation and soils. Erosional signatures include construction of orthogonal-elongate ponds and amorphous ponds, pond expansion, plucked marsh, marsh denudation, and shoreline erosion. Post-storm gravity reflux of floodwater draining from the wetlands forms dendritic incisions around the pond margins and locally integrates drainage pathways forming braided channels. Depositional signatures include emplacement of broad zones of organic wrack on topographic highs and inorganic deposits of variable thicknesses and lateral extents in the form of shore-parallel sandy washover terraces and interior-marsh mud blankets. Deformational signatures primarily involve laterally compressed marsh and displaced marsh mats and balls. Prolonged water impoundment and marsh salinization also are common impacts associated with wetland flooding by extreme storms. Many of the wetland features become legacies that record prior storm impacts and locally influence subsequent storm-induced morphological changes. Wetland losses caused by hurricane impacts depend directly on impact duration, which is controlled by the diameter of hurricane-force winds, forward speed of the storm, and wetland distance over which the storm passes. Distinguishing between wetland losses caused by storm impacts and losses associated with long-term delta-plain processes is critical for accurate modeling and prediction of future conversion of land to open water.

  20. Effectiveness of vegetation on phosphorus removal from reclaimed water by a subsurface flow wetland in a coastal area

    Institute of Scientific and Technical Information of China (English)

    Baoqing Shan; Liang Ao; Chunming Hu; Jiayu Song

    2011-01-01

    This work was conducted to evaluate the effectiveness and influence factors of vegetation on phosphorus (P) removal from reclaimed water in constructed wetlands.Comparisons were conducted between one pilot scale subsurface flow wetland (P-SSFW) and two demonstration subsurface flow wetlands,which were series-wound and named as first subsurface flow wetland (F-SSFW),and second subsurface flow wetland (S-SSFW),respectively.The three wetlands had the same vegetation and substrate,but different pH values,total dissolved solids (TDS) and P loads.Results showed that the P content in the vegetation shoots of the F-SSFW was 2.16 mg/g,while 2.31 mg/g in the S-SSFW and 2.69 mg/g in the P-SSFW.These differences were likely caused by the higher pH and TDS in the reclaimed water.The P content also differed among the tissues of the plant,which were 5.94-6.44 mg/g,2.20-2.77 mg/g,1.31-1.46mg/g and 1.53-1.88 mg/g in the flowers,leaves,stems,and roots,respectively.The greatest discrepancy was observed in the leaves,indicating that the environment of the wetlands had the greatest influence on the leaves.When the total phosphorus (TP) load was lower,the proportion of P removed by vegetation assimilation was 16.17% in the P-SSFW,12.90% in the F-SSFW and 13.29% in the S-SSFW.However,the relative removal efficiency by vegetation among the three wetlands did not vary greatly from that observed in other studies.Moreover,the influence of pH,TDS and TP load was not as great as the influence of the vegetation species,type of substrate,influent style or climate.

  1. Exploring scenarios of light pollution from coastal development reaching sea turtle nesting beaches near Cabo Pulmo, Mexico

    Directory of Open Access Journals (Sweden)

    Gregory M. Verutes

    2014-12-01

    Full Text Available New coastal development may offer economic benefits to resort builders and even local communities, but these projects can also impact local ecosystems, key wildlife, and the draw for tourists. We explore how light from Cabo Cortés, a proposed coastal development in Baja California Sur, Mexico, may alter natural light cues used by sea turtle hatchlings. We adapt a viewshed approach to model exterior light originating from the resort under plausible zoning scenarios. This spatially explicit information allows stakeholders to evaluate the likely impact of alternative development options. Our model suggests that direct light’s ability to reach sea turtle nesting beaches varies greatly by source location and height—with some plausible development scenarios leading to significantly less light pollution than others. Our light pollution maps can enhance decision-making, offering clear guidance on where to avoid elevated lamps or when to recommend lighting restrictions. Communities can use this information to participate in development planning to mitigate ecological, aesthetic and economic impacts from artificial lighting. Though tested in Mexico, our approach and free, open-source software can be applied in other places around the world to better understand and manage the threats of light pollution to sea turtles. Keywords: Artificial light, Viewshed analysis, Sea turtle conservation, Coastal resort management, InVEST

  2. The Gulf of Mexico Coastal Ocean Observing System: Building an MBON for the Florida Keys.

    Science.gov (United States)

    Howard, M.; Stoessel, M. M.; Currier, R. D.

    2016-02-01

    The Gulf of Mexico Coastal Ocean Observing System Regional Association (GCOOS-RA) Data Portal was designed to aggregate regional data and to serve it to the public through standards-based services in useful and desirable forms. These standards are established and sanctioned for use by the U.S. Integrated Ocean Observing System (IOOS) Program Office with inputs from experts on the Integrated Ocean Observation Committee and the RA informatics community. In 2012, with considerable input from staff from Ocean Biogeographical Information System USA (OBIS-USA), IOOS began to develop and adopt standards for serving biological datasets. GCOOS-RA applied these standards the following year and began serving fisheries independent data through an GCOOS ERDDAP server. In late 2014, GCOOS-RA partnered with the University of South Florida in a 5-year Marine Biodiversity Observing Network (MBON) Project sponsored by NOAA, NASA and BOEM. Work began in 2015. GCOOS' primary role is to aggregate, organize and serve data that are useful to an MBON for the Florida Keys National Marine Sanctuary. GCOOS, in collaboration with Axiom Data Science, will produce a decision support system (DSS) for stakeholders such as NOAA National Marine Sanctuaries Program managers. The datasets to be managed include environmental observations from: field surveys, fixed platforms, and satellites; GIS layers of: bathymetry, shoreline, sanctuary boundaries, living marine resources and habitats; outputs from ocean circulation models and ecosystem models (e.g., Ecopath/Ecosim) and Environmental DNA. Additionally, the DSS may be called upon to perform analyses, compute indices of biodiversity and present results in tabular, graphic and fused forms in an interactive setting. This presentation will discuss our progress to date for this challenging work in data integration.

  3. U.S. Coastal Relief Model - Florida and East Gulf of Mexico

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC's U.S. Coastal Relief Model (CRM) provides the first comprehensive view of the U.S. coastal zone integrating offshore bathymetry with land topography into a...

  4. Dissolved Organic Matter (DOM) Export from Watersheds to Coastal Oceans

    Science.gov (United States)

    Chen, R. F.; Gardner, G. B.; Peri, F.

    2016-02-01

    Dissolved organic matter (DOM) from terrestrial plants and soils is transported by surface waters and groundwaters to coastal ocean waters. Along the way, photochemical and biological degradation can remove DOM, and in situ processes such as phytoplankton leaching and sediment sources can add to the DOM in the river water. Wetlands, especially coastal wetlands can add significant amounts of DOM that is carried by rivers and is exported through estuaries to coastal systems. We will present observational data from a variety of coastal systems (San Francisco Bay, Boston Harbor, Chesapeake Bay, Hudson River, the Mississippi River, and a small salt marsh in the Gulf of Mexico). High resolution measurements of chromophoric dissolved organic matter (CDOM) can be correlated with dissolved organic carbon (DOC) so can be used to estimate DOC in specific systems and seasons. Gradients in CDOM/DOC combined with water fluxes can be used to estimate DOC fluxes from a variety of coastal watersheds to coastal systems. Influences of land use, system size, residence time, DOM quality, and photochemical and biological degradation will be discussed. The significance of coastal wetlands in the land-to-ocean export of DOC will be emphasized.

  5. China's natural wetlands: past problems, current status, and future challenges

    Science.gov (United States)

    Shuqing An; Harbin Li; Baohua Guan; Changfang Zhou; Zhongsheng Wang; Zifa Deng; Yingbiao Zhi; Yuhong Liu; Chi Xu; Shubo Fang; Jinhui Jiang; Hongli Li

    2007-01-01

    Natural wetlands, occupying 3.8% of China's land and providing 54.9% of ecosystem services, are unevenly distributed among eight wetland regions. Natural wetlands in China suffered great loss and degradation (e.g., 23.0% freshwater swamps, 51.2% coastal wetlands) because of the wetland reclamation during China's long history of civilization, and the...

  6. Species Profiles. Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Gulf of Mexico). WHITE SHRIMP.

    Science.gov (United States)

    1984-09-01

    regarding this report should be directed to one of the following addresses. Information Transfer Special ist National Coastal Ecosystems Team U.S. Fish and...snace not ’i Iled by, 7 rim, and thei, begin a henthic exi s- tier- a"jrias orua ntae lc tence. The timne )etween hatching and vih il th p ~ i p r i...Gulf of Mexico United States; a LTfe ist -y requirements of se- - regional management plan. Gulf lected finfish and shellfish in Coast Res. Lab. Tech

  7. Monitoring Drought along the Gulf of Mexico and the Southeastern Atlantic Ocean Using the Coastal Salinity Index

    Science.gov (United States)

    Conrads, P. A.; Rouen, L.; Lackstrom, K.; McCloskey, B.

    2017-12-01

    Coastal droughts have a different dynamic than upland droughts, which are typically characterized by agricultural, hydrologic, meteorological, and (or) socio-economic impacts. Drought uniquely affects coastal ecosystems due to changes in salinity conditions of estuarine creeks and rivers. The location of the freshwater-saltwater interface in surface-water bodies is an important factor in the ecological and socio-economic dynamics of coastal communities. The location of the interface determines the freshwater and saltwater aquatic communities, fisheries spawning habitat, and the freshwater availability for municipal and industrial water intakes. The severity of coastal drought may explain changes in Vibrio bacteria impacts on shellfish harvesting and occurrence of wound infection, fish kills, harmful algal blooms, hypoxia, and beach closures. To address the data and information gap for characterizing coastal drought, a coastal salinity index (CSI) was developed using salinity data. The CSI uses a computational approach similar to the Standardized Precipitation Index (SPI). The CSI is computed for unique time intervals (for example 1-, 6-, 12-, and 24-month) that can characterize the onset and recovery of short- and long-term drought. Evaluation of the CSI indicates that the index can be used for different estuary types (for example: brackish, oligohaline, or mesohaline), for regional comparison between estuaries, and as an index of wet conditions (high freshwater inflow) in addition to drought (saline) conditions. In 2017, three activities in 2017 will be presented that enhance the use and application of the CSI. One, a software package was developed for the consistent computation of the CSI that includes preprocessing of salinity data, filling missing data, computing the CSI, post-processing, and generating the supporting metadata. Two, the CSI has been computed at sites along the Gulf of Mexico (Texas to Florida) and the Southeastern Atlantic Ocean (Florida to

  8. 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

  9. Restoring coastal wetlands that were ditched for mosquito control: a preliminary assessment of hydro-leveling as a restoration technique

    Science.gov (United States)

    Smith, Thomas J.; Tiling, Ginger; Leasure, Pamela S.

    2007-01-01

    The wetlands surrounding Tampa Bay, Florida were extensively ditched for mosquito control in the 1950s. Spoil from ditch construction was placed adjacent to the wetlands ditches creating mound-like features (spoil-mounds). These mounds represent a loss of 14% of the wetland area in Tampa Bay. Spoil mounds interfere with tidal flow and are locations for non-native plants to colonize (e.g., Schinus terebinthifolius). Removal of the spoil mounds to eliminate exotic plants, restore native vegetation, and re-establish natural hydrology is a restoration priority for environmental managers. Hydro-leveling, a new technique, was tested in a mangrove forest restoration project in 2004. Hydro-leveling uses a high pressure stream of water to wash sediment from the spoil mound into the adjacent wetland and ditch. To assess the effectiveness of this technique, we conducted vegetation surveys in areas that were hydro-leveled and in non-hydro-leveled areas 3 years post-project. Adult Schinus were reduced but not eliminated from hydro-leveled mounds. Schinus seedlings however were absent from hydro-leveled sites. Colonization by native species was sparse. Mangrove seedlings were essentially absent (≈2 m−2) from the centers of hydro-leveled mounds and were in low density on their edges (17 m−2) in comparison to surrounding mangrove forests (105 m−2). Hydro-leveling resulted in mortality of mangroves adjacent to the mounds being leveled. This was probably caused by burial of pneumatophores during the hydro-leveling process. For hydro-leveling to be a useful and successful restoration technique several requirements must be met. Spoil mounds must be lowered to the level of the surrounding wetlands. Spoil must be distributed further into the adjacent wetland to prevent burial of nearby native vegetation. Finally, native species may need to be planted on hydro-leveled areas to speed up the re-vegetation process.

  10. Pipeline corridors through wetlands

    International Nuclear Information System (INIS)

    Zimmerman, R.E.; Wilkey, P.L.; Isaacson, H.R.

    1992-01-01

    This paper presents preliminary findings from six vegetational surveys of gas pipeline rights-of-way (ROW) through wetlands and quantifies the impacts of a 20-year-old pipeline ROW through a boreal forest wetland. Six sites of various ages were surveyed in ecosystems ranging from coastal marsh to forested wetland. At all sites except one, both the number and the percentage of wetland species on the Row approximated or exceeded those in the adjacent natural area. The boreal forest study showed that (1) adjacent natural wetland areas were not altered in type; (2) water sheet flow restriction had been reversed by nature; (3) no nonnative plant species invaded the natural area; (4) three-quarters of the ROW area was a wetland, and (5) the ROW increased diversity

  11. Benthic ecology of tropical coastal lagoons: Environmental changes over the last decades in the Términos Lagoon, Mexico

    Science.gov (United States)

    Grenz, Christian; Fichez, Renaud; Silva, Carlos Álvarez; Benítez, Laura Calva; Conan, Pascal; Esparza, Adolfo Contreras Ruiz; Denis, Lionel; Ruiz, Silvia Díaz; Douillet, Pascal; Martinez, Margarita E. Gallegos; Ghiglione, Jean-François; Mendieta, Francisco José Gutiérrez; Origel-Moreno, Montserrat; Garcia, Antonio Zoilo Marquez; Caravaca, Alain Muñoz; Pujo-Pay, Mireille; Alvarado, Rocío Torres; Zavala-Hidalgo, Jorge

    2017-10-01

    The Términos Lagoon is a 2000-km2 wide coastal lagoon linked to the largest river catchment in Mesoamerica. Economic development, together with its ecological importance, led the Mexican government to pronounce the Términos Lagoon and its surrounding wetlands as a Federal protected area for flora and fauna in 1994. It is characterized by small temperature fluctuations, but with two distinct seasons (wet and dry) that control the biological, geochemical, and physical processes and components. This paper presents a review of the available information about the Términos Lagoon. The review shows that the diversity of benthic communities is structured by the balance between marine and riverine inputs and that this structuration strongly influences the benthic metabolism and its coupling with the biogeochemistry of the water column. The paper also presents many specific drivers and recommendations for a long-term environmental survey strategy in the context of the expected Global Change in the Central American region.

  12. Scientist-teacher collaboration: Integration of real data from a coastal wetland into a high school life science ecology-based research project

    Science.gov (United States)

    Hagan, Wendy L.

    Project G.R.O.W. is an ecology-based research project developed for high school biology students. The curriculum was designed based on how students learn and awareness of the nature of science and scientific practices so that students would design and carry out scientific investigations using real data from a local coastal wetland. This was a scientist-teacher collaboration between a CSULB biologist and high school biology teacher. Prior to implementing the three-week research project, students had multiple opportunities to practice building requisite skills via 55 lessons focusing on the nature of science, scientific practices, technology, Common Core State Standards of reading, writing, listening and speaking, and Next Generation Science Standards. Project G.R.O.W. culminated with student generated research papers and oral presentations. Outcomes reveal students struggle with constructing explanations and the use of Excel to create meaningful graphs. They showed gains in data organization, analysis, teamwork and aspects of the nature of science.

  13. Soil seed banks and their germination responses to cadmium and salinity stresses in coastal wetlands affected by reclamation and urbanization based on indoor and outdoor experiments

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Junhong, E-mail: junhongbai@163.com; Huang, Laibin, E-mail: seahuanglaibin@gmail.com; Gao, Zhaoqin; Lu, Qiongqiong; Wang, Junjing; Zhao, Qingqing

    2014-09-15

    Highlights: • A higher germination rate of soil seed bank was observed in the indoor experiment. • The outdoor experiment showed larger number and destiny of germinated seedlings. • Urbanization had greater impacts on soil seed banks than wetland reclamation. • Soil seed banks for wetland restoration were more suitable in the reclaimed region. • Suitable salt or Cd levels could activate seedling emergence in the soil seed bank. - Abstract: Indoor and outdoor seedling emergence experiments were conducted to thoroughly investigate germination patterns as affected by reclamation and urbanization, the ecological characteristics of soil seed banks, and their relationships with environmental factors in both urbanized and reclaimed regions of the Pearl River Delta in coastal wetlands. The germination rate of the soil seed bank was higher in the indoor experiment compared with that in the outdoor experiment, whereas the number and destiny of the germinated seedlings were greater in the outdoor experiment. The species diversity and number, as well as the richness and evenness indices, were higher in the urbanized region compared with the reclaimed region. However, the dominance and Sørensen similarity indices were greater in the reclaimed region compared with those indices in the urbanized region. Higher salinity and Cadmium (Cd) levels could inhibit seed germination; however, their suitable ranges (i.e. [0–2000 mg kg{sup −1}] for salinity and [0–4.0 mg kg{sup −1}] for available Cd) can activate seedling emergence, and more seedlings germinated under the intersectional levels at 0.34 mg kg{sup −1} available Cd and 778.6 mg kg{sup −1} salinity. Seawater intrusion caused by the sea level rise will possibly result in the salt-tolerant community in this area due to increasing salinity.

  14. Soil seed banks and their germination responses to cadmium and salinity stresses in coastal wetlands affected by reclamation and urbanization based on indoor and outdoor experiments

    International Nuclear Information System (INIS)

    Bai, Junhong; Huang, Laibin; Gao, Zhaoqin; Lu, Qiongqiong; Wang, Junjing; Zhao, Qingqing

    2014-01-01

    Highlights: • A higher germination rate of soil seed bank was observed in the indoor experiment. • The outdoor experiment showed larger number and destiny of germinated seedlings. • Urbanization had greater impacts on soil seed banks than wetland reclamation. • Soil seed banks for wetland restoration were more suitable in the reclaimed region. • Suitable salt or Cd levels could activate seedling emergence in the soil seed bank. - Abstract: Indoor and outdoor seedling emergence experiments were conducted to thoroughly investigate germination patterns as affected by reclamation and urbanization, the ecological characteristics of soil seed banks, and their relationships with environmental factors in both urbanized and reclaimed regions of the Pearl River Delta in coastal wetlands. The germination rate of the soil seed bank was higher in the indoor experiment compared with that in the outdoor experiment, whereas the number and destiny of the germinated seedlings were greater in the outdoor experiment. The species diversity and number, as well as the richness and evenness indices, were higher in the urbanized region compared with the reclaimed region. However, the dominance and Sørensen similarity indices were greater in the reclaimed region compared with those indices in the urbanized region. Higher salinity and Cadmium (Cd) levels could inhibit seed germination; however, their suitable ranges (i.e. [0–2000 mg kg −1 ] for salinity and [0–4.0 mg kg −1 ] for available Cd) can activate seedling emergence, and more seedlings germinated under the intersectional levels at 0.34 mg kg −1 available Cd and 778.6 mg kg −1 salinity. Seawater intrusion caused by the sea level rise will possibly result in the salt-tolerant community in this area due to increasing salinity

  15. A comparison of the watershed hydrology of coastal forested wetlands and the mountainous uplands in the Southern US

    Science.gov (United States)

    G. Sun; S.G. McNulty; D.M. Amatya; R.W. Skaggs; L.W. Swift; J.P. Shepard; H. Riekerk

    2002-01-01

    Hydrology plays a critical roie in wetland development and ecosystem structure and functions. Hydrologic responses to forest management and climate change are diverse in the Southern United States due to topographic and climatic differences. This paper presents a comparison study on long-term hydrologic characteristics (long-term seasonal runoff patterns, water...

  16. Interactions Between Wetlands and Tidal Inlets

    National Research Council Canada - National Science Library

    Sanchez, Alejandro

    2008-01-01

    This Coastal and Hydraulics Engineering Technical Note (CHETN) presents numerical simulations investigating how the loss of wetlands in estuaries modifies tidal processes in inlet navigation channels...

  17. Effects of Bacillus thuringiensis israelensis and spinosad on adult emergence of the non-biting midges Polypedilum nubifer (Skuse) and Tanytarsus curticornis Kieffer (Diptera: Chironomidae) in coastal wetlands.

    Science.gov (United States)

    Duchet, Claire; Franquet, Evelyne; Lagadic, Laurent; Lagneau, Christophe

    2015-05-01

    To optimize their efficacy, some insecticides used for mosquito control are introduced into aquatic ecosystems where mosquito larvae develop (marshes, ponds, sanitation devices) and cannot escape from the treated water. However, this raises the question of possible effects of mosquito larvicides on non-target aquatic species. Bacillus thuringiensis var. israelensis (Bti), which is well-known for its selectivity for Nematocera dipterans, is widely used for mosquito control all over the world. Spinosad, a mixture of spinosyns A and D known as fermentation products of a soil actinomycete (Saccharopolyspora spinosa), is a biological neurotoxic insecticide with a broader action spectrum. It is a candidate larvicide for mosquito control, but some studies showed that it may be toxic to beneficial or non-target species, including non-biting midges. The present study was therefore undertaken to assess the impact of Bti and spinosad on natural populations of Polypedilum nubifer (Skuse) and Tanytarsus curticornis Kieffer (Diptera: Chironomidae) in field enclosures implemented in Mediterranean coastal wetlands. Unlike Bti, spinosad had a strong lethal effect on P. nubifer and seems to affect T. curticornis at presumed recommended rates for field application. Differences in the sensitivity of these two species to spinosad confirm that population dynamics need to be known for a proper assessment of the risk encountered by chironomids in wetlands where larvicide-based mosquito control occurs. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. The Gulf of Mexico Coastal Ocean Observing System: A Gulf Science Portal

    Science.gov (United States)

    Howard, M.; Gayanilo, F.; Kobara, S.; Jochens, A. E.

    2013-12-01

    The Gulf of Mexico Coastal Ocean Observing System's (GCOOS) regional science portal (gcoos.org) was designed to aggregate data and model output from distributed providers and to offer these, and derived products, through a single access point in standardized ways to a diverse set of users. The portal evolved under the NOAA-led U.S. Integrated Ocean Observing System (IOOS) program where automated largely-unattended machine-to-machine interoperability has always been a guiding tenet for system design. The web portal has a business unit where membership lists, new items, and reference materials are kept, a data portal where near real-time and historical data are held and served, and a products portal where data are fused into products tailored for specific or general stakeholder groups. The staff includes a system architect who built and maintains the data portal, a GIS expert who built and maintains the current product portal, the executive director who marshals resources to keep news items fresh and data manger who manages most of this. The business portal is built using WordPress which was selected because it appeared to be the easiest content management system for non-web programmers to add content to, maintain and enhance. The data portal is custom built and uses database, PHP, and web services based on Open Geospatial Consortium standards-based Sensor Observation Service (SOS) with Observations and Measurements (O&M) encodings. We employ a standards-based vocabulary, which we helped develop, which is registered at the Marine Metadata Interoperability Ontology Registry and Repository (http://mmisw.org). The registry is currently maintained by one of the authors. Products appearing in the products portal are primarily constructed using ESRI software by a Ph.D. level Geographer. Some products were built with other software, generally by graduate students over the years. We have been sensitive to the private sector when deciding which products to produce. While

  19. A new genus and species of cyclopoid (Crustacea, Copepoda, Cyclopinidae) from a coastal system in the Gulf of Mexico

    Science.gov (United States)

    Suárez-Morales, Eduardo; Almeyda-Artigas, Roberto Javier

    2015-01-01

    Abstract A new, monotypic genus of the interstitial marine cyclopoid copepod family Cyclopinidae G.O. Sars, 1913 is described from male and female specimens collected at Laguna de Términos, a large coastal lagoon system in the southern Gulf of Mexico. Mexiclopina campechana gen. et sp. n. cannot be adequately placed in any extant genus within the family. It differs from other cyclopinid genera in having a unique combination of characters including: 1) absence of modified brush-like seta on the mandibular exopod; 2) maxillule exopod with stout setal elements and brush-like setae absent; 3) basis of mandible with one seta; 4) presence of a modified seta on endopod of fourth leg; 5) fifth leg exopod unsegmented, armed with three elements in the female and five in the male; 6) intercoxal sclerite of first swimming leg with two medial spiniform processes on distal margin. The new genus is monotypic and appears to be most closely related to Cyclopina Claus, 1863 and Heptnerina Ivanenko & Defaye, 2004; the new species was compared with species of Cyclopina and it resembles Cyclopina americana Herbst, 1982 and Cyclopina caissara Lotufo, 1994. This is the second record of a species of Cyclopinidae in Mexico and the first in the Gulf of Mexico; the number of cyclopinid species recorded from the Americas is now 13. PMID:26668545

  20. Identification and classification of inland wetlands in Tamaulipas through remote sensing and geographic information systems

    Directory of Open Access Journals (Sweden)

    Wilver Enrique Salinas Castillo

    2012-03-01

    Full Text Available This work aimed to identify and classify artificial and natural inland wetlands in the state of Tamaulipas, Mexico, important for migratory aquatic birds. Historically, efforts nave been focused on natural coastal wetlands or specific water bodies located in highlands; however, these surveys have not reflected the dramatic changes in landscape due to farming development in northem Mexico in the Iatest decades. Agricultural fieids and dams associated to them provide food, water and shelterto many migratory birds and other species, a fact not well documented. Factors that may influence the use of wetlands were analyzed, including surface area, associated vegetation and proximity to agricultural fieids. The inventory of inland wetlands was based on the analysis of seven 2000 Landsat ETM satellite imagery and field data gathered from 261 sites surveyed in 2001. Baseline maps were created and GIS analyses were undertaken to classify these water bodies. More than 23 000 inland wetlands were identified, and the information derived from this study will be assist in the development of programs to manage and protect wetlands of importance for migratory aquatic birds in Tamaulipas.

  1. A Comprehensive Inventory of Alabama Coastal Zone Wetland Habitats (Swamps, Marshes, Submersed Grassbeds) from 1980 to 1982 (NCEI Accession 0161311)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitized maps of Mobile Bay and other coastal areas of Alabama, showing habitat types and species compositions of the vegetation in three broad categories of...

  2. Soil organic carbon storage changes in coastal wetlands of the modern Yellow River Delta from 2000 to 2009

    Directory of Open Access Journals (Sweden)

    J. Yu

    2012-06-01

    Full Text Available Soil carbon sequestration plays an essential role in mitigating atmospheric CO2 increases and the subsequently global greenhouse effect. The storages and dynamics of soil organic carbon (SOC of 0–30 cm soil depth in different landscape types including beaches, reservoir and pond, reed wetland, forest wetland, bush wetland, farmland, building land, bare land (severe saline land and salt field in the modern Yellow River Delta (YRD were studied based on the data of the regional survey and laboratory analysis. The landscape types were classified by the interpretation of remote sensing images of 2000 and 2009, which were calibrated by field survey results. The results revealed an increase of 10.59 km2 in the modem YRD area from 2000 to 2009. The SOC density varied ranging from 0.73 kg m−2 to 4.25 kg m−2 at depth of 0–30 cm. There were approx. 3.559 × 106 t and 3.545 × 106 t SOC stored in the YRD in 2000 and 2009, respectively. The SOC storages changed greatly in beaches, bush wetland, farm land and salt field which were affected dominantly by anthropogenic activities. The area of the YRD increased greatly within 10 years, however, the small increase of SOC storage in the region was observed due to landscape changes, indicating that the modern YRD was a potential carbon sink and anthropogenic activity was a key factor for SOC change.

  3. Elevated CO2 enhances biological contributions to elevation change in coastal wetlands by offsetting stressors associated with sea-level rise

    Science.gov (United States)

    Cherry, J.A.; McKee, K.L.; Grace, J.B.

    2009-01-01

    1. Sea-level rise, one indirect consequence of increasing atmospheric CO2, poses a major challenge to long-term stability of coastal wetlands. An important question is whether direct effects of elevated CO 2 on the capacity of marsh plants to accrete organic material and to maintain surface elevations outweigh indirect negative effects of stressors associated with sea-level rise (salinity and flooding). 2. In this study, we used a mesocosm approach to examine potential direct and indirect effects of atmospheric CO2 concentration, salinity and flooding on elevation change in a brackish marsh community dominated by a C3 species, Schoenoplectus americanus, and a C4 grass, Spartina patens. This experimental design permitted identification of mechanisms and their role in controlling elevation change, and the development of models that can be tested in the field. 3. To test hypotheses related to CO2 and sea-level rise, we used conventional anova procedures in conjunction with structural equation modelling (SEM). SEM explained 78% of the variability in elevation change and showed the direct, positive effect of S. americanus production on elevation. The SEM indicated that C3 plant response was influenced by interactive effects between CO2 and salinity on plant growth, not a direct CO2 fertilization effect. Elevated CO2 ameliorated negative effects of salinity on S. americanus and enhanced biomass contribution to elevation. 4. The positive relationship between S. americanus production and elevation change can be explained by shoot-base expansion under elevated CO 2 conditions, which led to vertical soil displacement. While the response of this species may differ under other environmental conditions, shoot-base expansion and the general contribution of C3 plant production to elevation change may be an important mechanism contributing to soil expansion and elevation gain in other coastal wetlands. 5. Synthesis. Our results revealed previously unrecognized interactions and

  4. 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

  5. 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.

  6. Gulf of Mexico Coastal and Ocean Zones Strategic Assessment: Data Atlas 1985 (NODC Accession 0126646)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Atlas contains metadata and shape files of 18 different species in the Gulf of Mexico as of 1985. The shapefiles display the spatial and temporal distribution of...

  7. 76 FR 60444 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Coastal Migratory Pelagic...

    Science.gov (United States)

    2011-09-29

    ..., cobia, cero, little tunny, dolphin, and bluefish (Gulf only). At present, only king mackerel, Spanish... bluefish from the Coastal Migratory Pelagic FMP. The Councils and NMFS have determined these species are...

  8. Complex community of nitrite-dependent anaerobic methane oxidation bacteria in coastal sediments of the Mai Po wetland by PCR amplification of both 16S rRNA and pmoA genes.

    Science.gov (United States)

    Chen, Jing; Zhou, Zhichao; Gu, Ji-Dong

    2015-02-01

    In the present work, both 16S rRNA and pmoA gene-based PCR primers were employed successfully to study the diversity and distribution of n-damo bacteria in the surface and lower layer sediments at the coastal Mai Po wetland. The occurrence of n-damo bacteria in both the surface and subsurface sediments with high diversity was confirmed in this study. Unlike the two other known n-damo communities from coastal areas, the pmoA gene-amplified sequences in the present work clustered not only with some freshwater subclusters but also within three newly erected marine subclusters mostly, indicating the unique niche specificity of n-damo bacteria in this wetland. Results suggested vegetation affected the distribution and community structures of n-damo bacteria in the sediments and n-damo could coexist with sulfate-reducing methanotrophs in the coastal ecosystem. Community structures of the Mai Po n-damo bacteria based on 16S rRNA gene were different from those of either the freshwater or the marine. In contrast, structures of the Mai Po n-damo communities based on pmoA gene grouped with the marine ones and were clearly distinguished from the freshwater ones. The abundance of n-damo bacteria at this wetland was quantified using 16S rRNA gene PCR primers to be 2.65-6.71 × 10(5) copies/g dry sediment. Ammonium and nitrite strongly affected the community structures and distribution of n-damo bacteria in the coastal Mai Po wetland sediments.

  9. Gulf of Mexico sales 157 and 161: Central and Western Planning areas. Final environmental impact statement: Volume 2, Sections IV.D through IX

    International Nuclear Information System (INIS)

    1995-01-01

    This volume of the environmental impact statement for sales in the Gulf of Mexico presents information dealing with impacts on the costal regions due to planned operations of the petroleum industry. Topics discussed include: impacts on sensitive coastal environments; coastal barrier beaches and associated dunes; wetlands; offshore resources; water quality; air quality; impacts to aquatic environments; impacts on marine birds; impacts on archaeological resources; impacts on socioeconomic conditions; topography; and analysis of a large oil spill

  10. Comparative age and growth of common snook Centropomus undecimalis (Pisces: Centropomidae from coastal and riverine areas in Southern Mexico

    Directory of Open Access Journals (Sweden)

    Martha A. Perera-Garcia

    2013-06-01

    Full Text Available Common snook Centropomus unidecimalis is an important commercial and fishery species in Southern Mexico, however the high exploitation rates have resulted in a strong reduction of its abundances. Since, the information about its population structure is scarce, the objective of the present research was to determine and compare the age structure in four important fishery sites. For this, age and growth of common snook were determined from specimens collected monthly, from July 2006 to March 2008, from two coastal (Barra Bosque and Barra San Pedro and two riverine (San Pedro and Tres Brazos commercial fishery sites in Tabasco, Mexico. Age was determined using sectioned saggitae otoliths and data analyzed by von Bertalanffy and Levenberg-Marquardt among others. Estimated ages ranged from 2 to 17 years. Monthly patterns of marginal increment formation and the percentage of otoliths with opaque rings on the outer edge demonstrated that a single annulus was formed each year. The von Bertalanffy parameters were calculated for males and females using linear adjustment and the non-linear method of Levenberg-Marquardt. The von Bertalanffy growth equations were FLt=109.21(1-e-0.21(t+0.57 for Barra Bosque, FLt=94.56(1-e-0.27(t+0.48 for Barra San Pedro, FLt=97.15(1-e-0.17(t+1.32 for San Pedro and FLt=83.77(1-e-0.26(t+0.49 for Tres Brazos. According to (Hotelling’s T², p<0.05 test growth was significantly greater for females than for males. Based on the Chen test, von Bertalanffy growth curves were different among the study sites (RSS, p<0.05. Based on the observed differences in growth parameters among sampling sites (coastal and riverine environments future research need to be conducted on migration and population genetics, in order to delineate the stock structure of this population and support management programs.

  11. Statewide summary for Mississippi: Chapter H in Emergent wetlands status and trends in the northern Gulf of Mexico: 1950-2010

    Science.gov (United States)

    Handley, Larry; Spear, Kathryn A.; Leggett, Ali; Thatcher, Cindy A.

    2012-01-01

    The Mississippi coastline is 113 linear kilometers (70 miles) long and its estuaries cover approximately 594 km (369 mi; Figure 1) (Handley and others, 2007). It has a man-made sand beach 43.5 km (27 mi) long and 595.5 km (370 mi) of shoreline (Klein and others, b., 1998). The Mississippi Sound extends across the coastal waters of the State and encompasses 175,412 ha (433,443 acres). It is bordered by the Mississippi coast; Mobile Bay, Ala.; the Gulf Islands National Seashore barrier islands; and Lake Borgne, La. The watersheds and drainages feeding into Mississippi Sound, excluding tidal exchange from the Gulf of Mexico, include Lake Borgne, Pearl River, Jourdan River, Wolf River, Biloxi River, Tchoutacabouffa River, Pascagoula River, and Mobile Bay. The Pascagoula River is one of the last undammed rivers in the continental U.S. and the only undammed river flowing into the Gulf of Mexico. Freshwater inflow into Mississippi Sound, excluding that from Mobile Bay, averages 882.4 m3 per second (30,806 ft3 per second). The Mississippi coastal zone contains approximately one-third of the State’s 120 ecological communities (Klein and others, a., 1998). Regional land use includes silviculture, agriculture, and urban development, including several coastal casinos. Commercial shipping, shipbuilding, phosphate rock refinement, and electric power generation companies include some of the industrial complexes found along the Mississippi coast. The three counties found along the Mississippi coast, Hancock, Harrison, and Jackson Counties, had a total population of 370,702 as of 2010, constituting 12.5 percent of the State’s population (U.S. Census Bureau, 2010). These counties cover over 160.9 km (100 mi) of coastline and are one of the fastest growing regions in the state (Klein and others, b., 1998).The casino industry, military installations, trade, and manufacturing provide most jobs in coastal Mississippi. Two major deep-water ports exist in coastal Mississippi

  12. ALOS PALSAR Applications in the Tropics and Subtropics: Characterisation, Mapping and Detecting Change in Forests and Coastal Wetlands

    Science.gov (United States)

    Lucas, Richard; Carreiras, Joao; Proisy, Christophe; Buniting, Peter

    2008-11-01

    Research undertaken as part of the Japanese Space Exploration Agency (JAXA) Principal Investigator (PI) and Kyoto and Carbon (K&C) programs has focused on the regional characterization (growth stage as a function of biomass and structure) and mapping of forests across northern Australia and mangroves (including wetlands) in selected tropical regions (northern Australia, Belize, French Guiana and Brazil) using Advanced Land Observing Satellite (ALOS) Phased Array L-band SAR (PALSAR) data, either singularly or in conjunction with other remote sensing (e.g., optical) data. Comparison against existing baseline datasets has allowed these data to be used for detecting change in these tropical and subtropical regions. Regional products (e.g., forest growth stage, mangrove/wetland extent and change) generated from the K&C dual polarimetric strip data are anticipated to benefit conservation of these ecosystems and allow better assessments of carbon stocks and changes in these as a function of natural and anthropogenic drivers, thereby supporting key international conventions.

  13. Phenology-based Spartina alterniflora mapping in coastal wetland of the Yangtze Estuary using time series of GaoFen satellite no. 1 wide field of view imagery

    Science.gov (United States)

    Ai, Jinquan; Gao, Wei; Gao, Zhiqiang; Shi, Runhe; Zhang, Chao

    2017-04-01

    Spartina alterniflora is an aggressive invasive plant species that replaces native species, changes the structure and function of the ecosystem across coastal wetlands in China, and is thus a major conservation concern. Mapping the spread of its invasion is a necessary first step for the implementation of effective ecological management strategies. The performance of a phenology-based approach for S. alterniflora mapping is explored in the coastal wetland of the Yangtze Estuary using a time series of GaoFen satellite no. 1 wide field of view camera (GF-1 WFV) imagery. First, a time series of the normalized difference vegetation index (NDVI) was constructed to evaluate the phenology of S. alterniflora. Two phenological stages (the senescence stage from November to mid-December and the green-up stage from late April to May) were determined as important for S. alterniflora detection in the study area based on NDVI temporal profiles, spectral reflectance curves of S. alterniflora and its coexistent species, and field surveys. Three phenology feature sets representing three major phenology-based detection strategies were then compared to map S. alterniflora: (1) the single-date imagery acquired within the optimal phenological window, (2) the multitemporal imagery, including four images from the two important phenological windows, and (3) the monthly NDVI time series imagery. Support vector machines and maximum likelihood classifiers were applied on each phenology feature set at different training sample sizes. For all phenology feature sets, the overall results were produced consistently with high mapping accuracies under sufficient training samples sizes, although significantly improved classification accuracies (10%) were obtained when the monthly NDVI time series imagery was employed. The optimal single-date imagery had the lowest accuracies of all detection strategies. The multitemporal analysis demonstrated little reduction in the overall accuracy compared with the

  14. No association between the use of Bti for mosquito control and the dynamics of non-target aquatic invertebrates in French coastal and continental wetlands

    International Nuclear Information System (INIS)

    Lagadic, Laurent; Schäfer, Ralf B.; Roucaute, Marc; Szöcs, Eduard; Chouin, Sébastien; Maupeou, Jérôme de; Duchet, Claire

    2016-01-01

    The environmental safety of Bacillus thuringiensis subsp. israelensis (Bti) is still controversial, mainly because most of the previous field studies on its undesired effects were spatially limited and did not address the relationship between community similarity and application time and frequency. No general statement can therefore be drawn on the usage conditions of Bti that insure protection of non-target organisms. The present study was conducted in eight sites distributed over the main geographical sectors where mosquito control is implemented in mainland France and Corsica. Changes in non-target aquatic invertebrates were followed at elapsed time after repeated applications of two Bti formulations (VectoBac® WDG or 12AS) up to four consecutive years. We examined the influence of both larvicide treatments and environmental variables on community dynamics and dissimilarity between treated and control areas. As it can be argued that chironomids are the most vulnerable group of non-target invertebrates, we scrutinised potential Bti-related effects on the dynamics of their community. The use of VectoBac® WDG and 12AS in coastal and continental wetlands had no immediate or long-term detectable effect on the taxonomic structure and taxa abundance of non-target aquatic invertebrate communities, including chironomids. This applied to the main habitats where mosquito larvae occur, regardless of their geographic location. Flooding, whose frequency and duration depend on local meteorological and hydrological conditions, was identified as the main environmental driver of invertebrate community dynamics. Our findings add support to the environmental safety of currently available Bti formulations when following recommended application rates and best mosquito control practices. - Highlights: • Bti is used in a variety of continental and coastal wetlands against mosquito larvae. • Bti dosages recommended for mosquito control do not affect non-target invertebrates.

  15. No association between the use of Bti for mosquito control and the dynamics of non-target aquatic invertebrates in French coastal and continental wetlands

    Energy Technology Data Exchange (ETDEWEB)

    Lagadic, Laurent, E-mail: Laurent.Lagadic@rennes.inra.fr [INRA, UMR985 Écologie et Santé des Écosystèmes, Agrocampus Ouest, 65 rue de Saint Brieuc, F-35042 Rennes (France); Schäfer, Ralf B. [Quantitative Landscape Ecology, Institute for Environmental Sciences, University of Koblenz-Landau, Fortstraße 7, D-76829 Landau (Germany); Roucaute, Marc [INRA, UMR985 Écologie et Santé des Écosystèmes, Agrocampus Ouest, 65 rue de Saint Brieuc, F-35042 Rennes (France); Szöcs, Eduard [Quantitative Landscape Ecology, Institute for Environmental Sciences, University of Koblenz-Landau, Fortstraße 7, D-76829 Landau (Germany); Chouin, Sébastien; Maupeou, Jérôme de [Etablissement Interdépartemental pour la Démoustication du Littoral Atlantique, 1 rue Toufaire, F-17300 Rochefort-sur-Mer (France); Duchet, Claire [Entente Interdépartementale pour la Démoustication du Littoral Méditerranéen, 165 avenue Paul-Rimbaud, F-34184 Montpellier (France); and others

    2016-05-15

    The environmental safety of Bacillus thuringiensis subsp. israelensis (Bti) is still controversial, mainly because most of the previous field studies on its undesired effects were spatially limited and did not address the relationship between community similarity and application time and frequency. No general statement can therefore be drawn on the usage conditions of Bti that insure protection of non-target organisms. The present study was conducted in eight sites distributed over the main geographical sectors where mosquito control is implemented in mainland France and Corsica. Changes in non-target aquatic invertebrates were followed at elapsed time after repeated applications of two Bti formulations (VectoBac® WDG or 12AS) up to four consecutive years. We examined the influence of both larvicide treatments and environmental variables on community dynamics and dissimilarity between treated and control areas. As it can be argued that chironomids are the most vulnerable group of non-target invertebrates, we scrutinised potential Bti-related effects on the dynamics of their community. The use of VectoBac® WDG and 12AS in coastal and continental wetlands had no immediate or long-term detectable effect on the taxonomic structure and taxa abundance of non-target aquatic invertebrate communities, including chironomids. This applied to the main habitats where mosquito larvae occur, regardless of their geographic location. Flooding, whose frequency and duration depend on local meteorological and hydrological conditions, was identified as the main environmental driver of invertebrate community dynamics. Our findings add support to the environmental safety of currently available Bti formulations when following recommended application rates and best mosquito control practices. - Highlights: • Bti is used in a variety of continental and coastal wetlands against mosquito larvae. • Bti dosages recommended for mosquito control do not affect non-target invertebrates.

  16. UV filters are an environmental threat in the Gulf of Mexico: a case study of Texas coastal zones

    Directory of Open Access Journals (Sweden)

    Hamidreza Sharifan

    2016-10-01

    Full Text Available UV filters are the main ingredients in many cosmetics and personal care products. A significant amount of lipophilic UV filters annually enters the surface water due to large numbers of swimmers and sunbathers. The nature of these compounds cause bioaccumulation in commercial fish, particularly in estuarine areas. Consequently, biomagnification in the food chain will occur. This study estimated the amount of four common UV filters (ethylhexyl methoxycinnamate, EHMC; octocrylene, OC; butyl methoxydibenzoylmethane, BM-DBM; and benzophenone-3, BP3, which may enter surface water in the Gulf of Mexico. Our data analysis was based on the available research data and EPA standards (age classification/human body parts. The results indicated that among the 14 counties in Texas coastal zones, Nueces, with 43 beaches, has a high potential of water contamination through UV filters; EHMC: 477 kg year−1; OC: 318 kg year−1; BM-DBM: 258 kg year−1; and BP by 159 kg year−1. Refugio County, with a minimum number of beaches, indicated the lowest potential of UV filter contamination. The sensitive estuarine areas of Galveston receive a significant amount of UV filters. This article suggests action for protecting Texas estuarine areas and controlling the number of tourists and ecotourism that occurs in sensitive areas of the Gulf of Mexico.

  17. Coastal and river flood risk analyses for guiding economically optimal flood adaptation policies: a country-scale study for Mexico

    Science.gov (United States)

    Haer, Toon; Botzen, W. J. Wouter; van Roomen, Vincent; Connor, Harry; Zavala-Hidalgo, Jorge; Eilander, Dirk M.; Ward, Philip J.

    2018-06-01

    Many countries around the world face increasing impacts from flooding due to socio-economic development in flood-prone areas, which may be enhanced in intensity and frequency as a result of climate change. With increasing flood risk, it is becoming more important to be able to assess the costs and benefits of adaptation strategies. To guide the design of such strategies, policy makers need tools to prioritize where adaptation is needed and how much adaptation funds are required. In this country-scale study, we show how flood risk analyses can be used in cost-benefit analyses to prioritize investments in flood adaptation strategies in Mexico under future climate scenarios. Moreover, given the often limited availability of detailed local data for such analyses, we show how state-of-the-art global data and flood risk assessment models can be applied for a detailed assessment of optimal flood-protection strategies. Our results show that especially states along the Gulf of Mexico have considerable economic benefits from investments in adaptation that limit risks from both river and coastal floods, and that increased flood-protection standards are economically beneficial for many Mexican states. We discuss the sensitivity of our results to modelling uncertainties, the transferability of our modelling approach and policy implications. This article is part of the theme issue `Advances in risk assessment for climate change adaptation policy'.

  18. Near-coastal ocean variability off southern Tamaulipas - northern Veracruz, western Gulf of Mexico, during spring-summer 2013

    Science.gov (United States)

    Rivas, David

    2016-04-01

    Six months of observations from a near-coastal mooring deployed off southern Tamaulipas-northern Veracruz coast (western Gulf of Mexico) during spring-summer 2013 provides velocity, temperature, salinity, sea level, and dissolved oxygen series in a region which ocean dynamics is still poorly understood. As shown in a preceding analysis of this region's winter circulation for winter 2012-2013, coastal trapped motions associated with the regional invasion of synoptic cold fronts modulate the local variability; this pattern remains in the spring 2013, when even more intense events of alongshore flow (>50 cm/s) are observed. This intensified flow is associated with a significant decrease in the dissolved oxygen, most probably related to an influence of hypoxic waters coming from the northern Gulf. In late spring-mid summer, the wind pattern corresponds to persistent southeasterly winds that favor the occurrence of a local upwelling, which maintains a local thermal reduction (>3 degrees Celsius) and is associated with a persistent northward flow (>30 cm/s). The late summer was characterized by a significant tropical-cyclone activity, when a depression, a storm, and a hurricane affected the western Gulf. These tropical systems caused an intense precipitation and hence an important intensification of the local riverine discharge, and the winds enhanced the mixing of such riverine waters, via mostly kinetic stirring and Ekman pumping.

  19. Assessment of economic impact of offshore and coastal discharge requirements on present and future operations in the Gulf of Mexico. Final report

    International Nuclear Information System (INIS)

    Lindsey, R.

    1996-06-01

    The high potential costs of compliance associated with new effluent guidelines for offshore and coastal oil and gas operations could significantly affect the economics of finding, developing, and producing oil and gas in the Gulf of Mexico. This report characterizes the potential economic impacts of alternative treatment and discharge regulations for produced water on reserves and production in Gulf of Mexico coastal, territorial and outer continental shelf (OCS) waters, quantifying the impacts of both recent regulatory changes and possible more stringent requirements. The treatment technologies capable of meeting these requirements are characterized in terms of cost, performance, and applicability to coastal and offshore situations. As part of this analysis, an extensive database was constructed that includes oil and gas production forecasts by field, data on existing platforms, and the current treatment methods in place for produced water treatment and disposal on offshore facilities. This work provides the first comprehensive evaluation of the impacts of alternative regulatory requirements for produced water management and disposal in coastal and offshore areas of the Gulf of Mexico

  20. 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

  1. 78 FR 42021 - Atlantic Highly Migratory Species; Commercial Gulf of Mexico Aggregated Large Coastal Shark and...

    Science.gov (United States)

    2013-07-15

    ... system by the dealer and received by NMFS no later than midnight, local time, of the first Tuesday... the Gulf of Mexico region that were harvested, off-loaded, and sold, traded, or bartered, prior to the..., or bartered from a vessel that fishes only in state waters and that has not been issued an Atlantic...

  2. A multigear protocol for sampling crayfish assemblages in Gulf of Mexico coastal streams

    Science.gov (United States)

    William R. Budnick; William E. Kelso; Susan B. Adams; Michael D. Kaller

    2018-01-01

    Identifying an effective protocol for sampling crayfish in streams that vary in habitat and physical/chemical characteristics has proven problematic. We evaluated an active, combined-gear (backpack electrofishing and dipnetting) sampling protocol in 20 Coastal Plain streams in Louisiana. Using generalized linear models and rarefaction curves, we evaluated environmental...

  3. Soil seed banks and their germination responses to cadmium and salinity stresses in coastal wetlands affected by reclamation and urbanization based on indoor and outdoor experiments.

    Science.gov (United States)

    Bai, Junhong; Huang, Laibin; Gao, Zhaoqin; Lu, Qiongqiong; Wang, Junjing; Zhao, Qingqing

    2014-09-15

    Indoor and outdoor seedling emergence experiments were conducted to thoroughly investigate germination patterns as affected by reclamation and urbanization, the ecological characteristics of soil seed banks, and their relationships with environmental factors in both urbanized and reclaimed regions of the Pearl River Delta in coastal wetlands. The germination rate of the soil seed bank was higher in the indoor experiment compared with that in the outdoor experiment, whereas the number and destiny of the germinated seedlings were greater in the outdoor experiment. The species diversity and number, as well as the richness and evenness indices, were higher in the urbanized region compared with the reclaimed region. However, the dominance and Sørensen similarity indices were greater in the reclaimed region compared with those indices in the urbanized region. Higher salinity and Cadmium (Cd) levels could inhibit seed germination; however, their suitable ranges (i.e. [0-2,000 mg kg(-1)] for salinity and [0-4.0 mg kg(-1)] for available Cd) can activate seedling emergence, and more seedlings germinated under the intersectional levels at 0.34 mg kg(-1) available Cd and 778.6 mg kg(-1) salinity. Seawater intrusion caused by the sea level rise will possibly result in the salt-tolerant community in this area due to increasing salinity. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. HYDROGEOLOGY AND CONCEPTUAL MODEL OF THE KARSTIC COASTAL AQUIFER IN NORTHERN YUCATAN STATE, MEXICO

    Directory of Open Access Journals (Sweden)

    Miguel J Villasuso-Pino

    2011-04-01

    Full Text Available The coastal zone of northern Yucatan Peninsula (YP is mainly constituted by Tertiary limestones, covered by Pleistocen limestones, where there exist swamps and estuary systems, locally called “rías”, with mouths connecting them to the sea and hence being a way for an important amount of groundwater to discharge, like in Ría Lagartos and Celestún. These limestones have karstic layers located at depths from 8 to 16 meters below terrain surface.  It is in these layers where groundwater mainly flows toward coast, passing below the sand dune and discharging in the sea in the form of submarine springs which in many cases manifest themselves on the marine surface depending on the hydraulic or piezometric fresh water head. The width of the superficial limestone within this coastal fringe, called “caliche”, varies from 5 to 10 kilometers in the study zone (Chuburna-Progreso-Chicxulub.  Its permeability is extremely low, so it constitutes a confining layer that impedes superficial waters to percolate toward groundwater.  The hydraulic head of the groundwater below this confining layer is over the mean sea level and also over the swamp water level, coastal lagoons and estuaries. There are two important hydrological phenomena that occur in this coastal fringe: 1 There is no recharge to the aquifer (groundwater due to limestone rock outcrops is impermeable or semipermeable; and 2 groundwater pressure is not lost, nor saline interfase is rised if the superficial layer is broken.  The groundwater pollution vulnerability within this coastal fringe is less than that for the superficial saline waters of swamps and estuaries, because of caliche’s low intrinsic permeability that impedes percolation.

  5. Changes in Landscape Pattern of Wetland around Hangzhou Bay

    Science.gov (United States)

    Lin, Wenpeng; Li, Yuan; Xu, Dan; Zeng, Ying

    2018-04-01

    Hangzhou Bay is an important estuarial coastal wetland, which offers a large number of land and ecological resources. It plays a significant role in the sustainable development of resources, environment and economy. In this paper, based on the remote sensing images in 1996, 2005 and 2013, we extracted the coastal wetland data and analyzed the wetland landscape pattern of the Hangzhou Bay in the past 20 years. The results show that: (1) the area of coastal wetland is heading downwards in the recent decades. Paddy field and the coastal wetland diminish greatly. (2) the single dynamic degree of wetland of the Hangzhou Bay displays that paddy fields and coastal wetlands are shrinking, but lakes, reservoirs and ponds are constantly expanding. (3) the wetland landscape pattern index shows that total patch area of the coastal wetland and paddy fields have gradually diminished. The Shannon diversity index, the Shannon evenness index as well as the landscape separation index of the coastal wetlands in the Hangzhou Bay increase steadily. The landscape pattern in the study area has shown a trend of high fragmentation, dominance decreases, but some dominant landscape still exist in this region. (4) Urbanization and natural factors lead to the reduction of wetland area. Besides the pressure of population is a major threat to the wetland. The study will provide scientific basis for long-term planning for this region.

  6. The Role of Created and Restored Wetlands in Mitigating N and P Pollutants in Agricultural Landscapes: Case Studies in the Florida Everglades, Mississippi-Ohio-Missouri Basin, and Laurentian Great Lakes

    Science.gov (United States)

    Mitsch, W. J.

    2016-12-01

    On a global scale, we have lost half of our original wetlands to our current extent of 8 to 12 million km2, with most of that loss in the 20th century. In the United States, we lost 50% of our wetlands by the beginning of the 1970s. I am proposing here a sizeable increase in our wetland resources for solving the diminishing wetland habitat problem, but with the strategic purpose of minimizing the excess phosphorus and nitrogen in our aquatic ecosystems, with the added benefit of sometimes sequesting carbon from the atmosphere, in our rural, urban, and coastal landscapes in a sustainable fashion. Examples include attempts to minimize phosphorus inflows to the Florida Everglades with wetlands to quite low concentrations and a proposal to restore parts of the Black Swamp in NW Ohio to minimize eutrophication of Lake Erie in the Laurentian Great Lakes. Nitrogen retention by wetlands and riparian forests in the Mississippi-Ohio-Missouri Basin, especially in Midwestern USA, has been proposed for 15 years as a solution and endorsed by the Federal government to solve the seasonal hypoxia in the northern portion of the Gulf of Mexico, but there has been little if any progress over those 15 years. Solutions to recycle the nutrients retained in the wetlands back to agriculture to decrease fertilizer use will be presented as a solution to the multiple problems of wetland habitat loss, downstream lake, reservoir, river, and coastal nutrient pollution, diminishing supplies of phosphorus fertilizer, and fertilizer costs.

  7. Nutrient fluxes and net metabolism in a coastal lagoon SW peninsula of Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    Cervantes Duarte, R.

    2016-09-01

    Full Text Available Fluxes of nutrients and net metabolism were estimated in coastal lagoon Magdalena Bay using LOICZ biogeochemical model. In situ data were obtained from 14 sites in the lagoon and also from a fixed site in the adjacent ocean area. Intense upwelling (February to July and faint upwelling (August to January were analyzed from monthly time series. The Temperature, nitrite + nitrate, ammonium and phosphate within the lagoon showed significant differences (p<0.05 between the two periods. Salinity (p=0.408 was more homogeneous (no significantly different due to mixing processes. During the intense upwelling period, nutrients increased in and out of the lagoon due to the influence of Transitional Water and Subartic Water transported by the California Current. However, during the faint upwelling, from August to January, the Transition Water and Subtropical Surface Water were predominant. Magdalena Bay showed denitrification processes of throughout the year as it occurred in other semi-arid coastal lagoons. It also showed a net autotrophic metabolism during intense upwelling and heterotrophic metabolism during faint upwelling. Understanding nutrient flows and net metabolism through simple biogeochemical models can provide tools for better management of the coastal zone.

  8. Constructed Wetlands

    Science.gov (United States)

    these systems can improve water quality, engineers and scientists construct systems that replicate the functions of natural wetlands. Constructed wetlands are treatment systems that use natural processes

  9. Responses of Isolated Wetland Herpetofauna to Upland Forest Management

    International Nuclear Information System (INIS)

    Russell, K.R.; Hanlin, H.G.; Wigley, T.B.; Guynn, D.C. Jr.

    2002-01-01

    Measurement of responses of herpetofauna at isolated wetlands in the Coastal Plain of South Carolina to disturbance of adjacent loblolly pine forest. Many species of isolated wetland herpetofauna in the Southeastern Coastal Plain may tolerate some disturbance in adjacent upland stands. Responses of isolated wetland herpetofauna to upland silviculture and the need for adjacent forested buffers likely depend on the specific landscape context in which the wetlands occur and composition of the resident herpetofaunal community

  10. Synergy between LIDAR and RADARSAT-2 images for the recognition of vegetation structures in the coastal wetlands of the Danube Delta

    Science.gov (United States)

    Niculescu, Simona; Lardeux, Cédric; Grigoras, Ion; Hanganu, Jenica; David, Laurence

    2014-05-01

    Wetlands are among the most productive environments in the world and are characterized by exceptional biological diversity. Despite their indisputable importance, these environments remain among the most endangered ecosystems in the world due to drainage, drying out, pollution or overexploitation of resources. The Danube Delta, a coastal wetland of the Black Sea, cannot escape these dangers and, to preserve its resources, it has been declared a Biosphere Reserve (in 1993). The biodiversity of this area is remarkable and it possesses one of the largest reed in the world (a continuous 2,700 km² reed cover). The main goal of this project is to determine, characterize and derive functional descriptors of the vegetation structures, Phragmites australis species of the Danube Delta being the most prevalent. For this purpose, this project aims, on the one hand, at interpreting LIDAR measurements (acquired in May 2011) in conjunction with RADARSAT-2 satellite observations (acquired in early June 2011) and, on the other hand, at validating the results obtained by the introduction of the spectral measurements of the main vegetation classes into a Spectral Angle Mapper algorithm applied to a SPOT-5 image (May 2011). The LIDAR data allow the assessment of vegetation height with an accuracy of a few centimeters. Hence, the various vegetation layers can be accurately mapped. However, the differentiation of the various vegetation formations within a same layer requires the contribution of complementary data sources such as RADARSAT-2 data. The radar measurements are derived using the C band (λ wavelength = 5.3 cm) providing additional information on the vegetation cover structure with regard to roughness, moisture and biomass. The simultaneous acquisition of HH, HV and VV polarizations allows the differentiation of the areas according to their response to different polarizations by establishing their polarimetric signatures. Based on these raw data, we were able to derive other

  11. Establishing a baseline of estuarine submerged aquatic vegetation resources across salinity zones within coastal areas of the northern Gulf of Mexico

    Science.gov (United States)

    Hillmann, Eva R.; DeMarco, Kristin; LaPeyre, Megan K.

    2016-01-01

    Coastal ecosystems are dynamic and productive areas that are vulnerable to effects of global climate change. Despite their potentially limited spatial extent, submerged aquatic vegetation (SAV) beds function in coastal ecosystems as foundation species, and perform important ecological services. However, limited understanding of the factors controlling SAV distribution and abundance across multiple salinity zones (fresh, intermediate, brackish, and saline) in the northern Gulf of Mexico restricts the ability of models to accurately predict resource availability. We sampled 384 potential coastal SAV sites across the northern Gulf of Mexico in 2013 and 2014, and examined community and species-specific SAV distribution and biomass in relation to year, salinity, turbidity, and water depth. After two years of sampling, 14 species of SAV were documented, with three species (coontail [Ceratophyllum demersum], Eurasian watermilfoil [Myriophyllum spicatum], and widgeon grass [Ruppia maritima]) accounting for 54% of above-ground biomass collected. Salinity and water depth were dominant drivers of species assemblages but had little effect on SAV biomass. Predicted changes in salinity and water depths along the northern Gulf of Mexico coast will likely alter SAV production and species assemblages, shifting to more saline and depth-tolerant assemblages, which in turn may affect habitat and food resources for associated faunal species.

  12. Concentrations and sources of polycyclic aromatic hydrocarbons in surface coastal sediments of the northern Gulf of Mexico

    Science.gov (United States)

    2014-01-01

    Background Coastal sediments in the northern Gulf of Mexico have a high potential of being contaminated by petroleum hydrocarbons, such as polycyclic aromatic hydrocarbons (PAHs), due to extensive petroleum exploration and transportation activities. In this study we evaluated the spatial distribution and contamination sources of PAHs, as well as the bioavailable fraction in the bulk PAH pool, in surface marsh and shelf sediments (top 5 cm) of the northern Gulf of Mexico. Results PAH concentrations in this region ranged from 100 to 856 ng g−1, with the highest concentrations in Mississippi River mouth sediments followed by marsh sediments and then the lowest concentrations in shelf sediments. The PAH concentrations correlated positively with atomic C/N ratios of sedimentary organic matter (OM), suggesting that terrestrial OM preferentially sorbs PAHs relative to marine OM. PAHs with 2 rings were more abundant than those with 5–6 rings in continental shelf sediments, while the opposite was found in marsh sediments. This distribution pattern suggests different contamination sources between shelf and marsh sediments. Based on diagnostic ratios of PAH isomers and principal component analysis, shelf sediment PAHs were petrogenic and those from marsh sediments were pyrogenic. The proportions of bioavailable PAHs in total PAHs were low, ranging from 0.02% to 0.06%, with higher fractions found in marsh than shelf sediments. Conclusion PAH distribution and composition differences between marsh and shelf sediments were influenced by grain size, contamination sources, and the types of organic matter associated with PAHs. Concentrations of PAHs in the study area were below effects low-range, suggesting a low risk to organisms and limited transfer of PAHs into food web. From the source analysis, PAHs in shelf sediments mainly originated from direct petroleum contamination, while those in marsh sediments were from combustion of fossil fuels. PMID:24641695

  13. Dynamics of mangrove-marsh ecotones in subtropical coastal wetlands: fire, sea-level rise, and water levels

    Science.gov (United States)

    Smith, Thomas J.; Foster, Ann M.; Tiling-Range, Ginger; Jones, John W.

    2013-01-01

    Ecotones are areas of sharp environmental gradients between two or more homogeneous vegetation types. They are a dynamic aspect of all landscapes and are also responsive to climate change. Shifts in the position of an ecotone across a landscape can be an indication of a changing environment. In the coastal Everglades of Florida, USA, a dominant ecotone type is that of mangrove forest and marsh. However, there is a variety of plants that can form the marsh component, including sawgrass (Cladium mariscus [L.] Pohl), needlegrass rush (Juncus roemerianus Scheele), and spikerush (Eleocharis spp.). Environmental factors including water depth, soil type, and occurrence of fires vary across these ecotones, influencing their dynamics. Altered freshwater inflows from upstream and increasing sea level over the past 100 years may have also had an impact. We analyzed a time series of historical aerial photographs for a number of sites in the coastal Everglades and measured change in position of mangrove–marsh ecotones. For three sites, detailed maps were produced and the area of marsh, mangrove, and other habitats was determined for five periods spanning the years 1928 to 2004. Contrary to our initial hypothesis on fire, we found that fire did not prevent mangrove expansion into marsh areas but may in fact assist mangroves to invade some marsh habitats, especially sawgrass. Disparate patterns in mangrove–marsh change were measured at two downstream sites, both of which had multiple fires over from 1948 to 2004. No change in mangrove or marsh area was measured at one site. Mangrove area increased and marsh area decreased at the second of these fire-impacted sites. We measured a significant increase in mangrove area and a decline in marsh area at an upstream site that had little occurrence of fire. At this site, water levels have increased significantly as sea level has risen, and this has probably been a factor in the mangrove expansion.

  14. Inventory of medium-sized and large mammals in the wetlands of Laguna de Terminos and Pantanos de Centla, Mexico

    OpenAIRE

    Hidalgo-Mihart,Mircea G.; Contreras-Moreno,Fernando M.; Jesús-de la Cruz,Alejandro; Juárez-López,Rugieri; Bravata de la Cruz,Yaribeth; Pérez-Solano,Luz A.; Hernández-Lara,Carolina; Friedeberg,Diana; Thornton,Dan; Koller-González,Juan M.

    2017-01-01

    Wetlands are one of the most productive ecosystems in the world. However, they have received little attention in the tropics. Biodiversity data from the Terminos-Centla wetlands is limited despite the conservation efforts to protect these wetlands. In this study we list the medium-szied and large mammals from 8 sites within the Terminos-Centla wetlands. We recorded 30 native and 1 introduced species, representing 9 orders, 14 families, and 27 genera. Four of the recorded species are Threatene...

  15. Phytoplankton variation and its relation to nutrients and allochthonous organic matter in a coastal lagoon on the Gulf of Mexico

    Science.gov (United States)

    Aké-Castillo, José A.; Vázquez, Gabriela

    2008-07-01

    In tropical and subtropical zones, coastal lagoons are surrounded by mangrove communities which are a source of high quantity organic matter that enters the aquatic system through litter fall. This organic matter decomposes, becoming a source of nutrients and other substances such as tannins, fulvic acids and humic acids that may affect the composition and productivity of phytoplankton communities. Sontecomapan is a coastal lagoon located in the southern Gulf of Mexico, which receives abundant litter fall from mangrove. To study the phytoplankton composition and its variation in this lagoon from October 2002 to October 2003, we evaluated the concentrations of dissolved folin phenol active substances (FPAS) as a measure of plant organic matter, salinity, temperature, pH, O 2, N-NH 4+, N-NO 3-, P-PO 43-, Si-SiO 2, and phytoplanktonic cell density in different mangrove influence zones including the three main rivers that feed the lagoon. Nutrients concentrations depended on freshwater from rivers, however these varied seasonally. Concentrations of P-PO 43-, N-NH 4+ and FPAS were the highest in the dry season, when maximum mangrove litter fall is reported. Variation of these nutrients seemed to depend on the internal biogeochemical processes of the lagoon. Blooms of diatoms ( Skeletonema spp., Cyclotella spp. and Chaetoceros holsaticus) and dinoflagellates ( Peridinium aff. quinquecorne, Prorocentrum cordatum) occurred seasonally and in the different mangrove influence zones. The high cell densities in these zones and the occurrence of certain species and its ordination along gradient of FPAS in a canonical correspondence analysis, suggest that plant organic matter (i.e. mangrove influence) may contribute to phytoplankton dynamics in Sontecomapan lagoon.

  16. Monetary valuation of salicylic acid, methylparaben and THCOOH in a Mediterranean coastal wetland through the shadow prices methodology.

    Science.gov (United States)

    Bellver-Domingo, Águeda; Fuentes, Ramón; Hernández-Sancho, Francesc; Carmona, Eric; Picó, Yolanda; Hernández-Chover, Vicent

    2018-06-15

    The presence of pharmaceutical and personal care products and drugs of abuse (PPCPs) in wastewater treatment plants (WWTPs) indicates discharge of the effluent may not be suitable for the ecological balance of water ecosystems, such as wetlands. These PPCPs degrade water quality, considered as an ecosystem service (ES), provoking serious environmental impacts. Assessing the monetary value of PPCPs can be used as a proxy for environmental status of the ES of water quality (ESWQ). Considering PPCPs as non-desirable outputs of WWTPs, the shadow prices methodology has been implemented using directional distance function to measure the environmental avoided cost of removing salicylic acid (SA), methylparaben (MP), and THCOOH from WWTPs effluents discharged to Albufera Natural Park (Spain). The SA shows the highest shadow price (138.16 €/μg), followed by THCOOH (48.15 €/μg), and MP (30.66 €/μg). These values are interpreted as the environmental cost that would be avoided if SA, MP, and THCOOH were removed from WWTPs effluents. The non-parametric tests show that wastewater treatment technology, together with population equivalent (as a proxy of the size of urban areas) and seasonality are factors that influence shadow prices obtained. The approach used in this study highlights the use of PPCPs as status indicators of ESWQ quantified in monetary units. As a way to synthesize the essential concepts to implement the shadow prices approach, this study proposes a flow diagram to represent the relationship between all the factors involved in this work. The use of shadow prices methodology proves that removing SA, MP, and THCOOH is associated with a measurable improvement in the ESWQ of Albufera Natural Park. The findings of this study will be useful for plant managers in order to make decisions about the removal of PPCPs in WWTPs effluents. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Wetlands of the Gulf Coast

    Science.gov (United States)

    2001-01-01

    This set of images from the Multi-angle Imaging SpectroRadiometer highlights coastal areas of four states along the Gulf of Mexico: Louisiana, Mississippi, Alabama and part of the Florida panhandle. The images were acquired on October 15, 2001 (Terra orbit 9718)and represent an area of 345 kilometers x 315 kilometers.The two smaller images on the right are (top) a natural color view comprised of red, green, and blue band data from MISR's nadir(vertical-viewing) camera, and (bottom) a false-color view comprised of near-infrared, red, and blue band data from the same camera. The predominantly red color of the false-color image is due to the presence of vegetation, which is bright at near-infrared wavelengths. Cities appear as grey patches, with New Orleans visible at the southern edge of Lake Pontchartrain, along the left-hand side of the images. The Lake Pontchartrain Bridge runs approximately north-south across the middle of the lake. The distinctive shape of the Mississippi River Delta can be seen to the southeast of New Orleans. Other coastal cities are visible east of the Mississippi, including Biloxi, Mobile and Pensacola.The large image is similar to the true-color nadir view, except that red band data from the 60-degree backward-looking camera has been substituted into the red channel; the blue and green data from the nadir camera have been preserved. In this visualization, green hues appear somewhat subdued, and a number of areas with a reddish color are present, particularly near the mouths of the Mississippi, Pascagoula, Mobile-Tensaw, and Escambia Rivers. Here, the red color is highlighting differences in surface texture. This combination of angular and spectral information differentiates areas with aquatic vegetation associated with poorly drained bottom lands, marshes, and/or estuaries from the surrounding surface vegetation. These wetland regions are not as well differentiated in the conventional nadir views.Variations in ocean color are apparent in

  18. Metal discharges by Sinaloa Rivers to the coastal zone of NW Mexico.

    Science.gov (United States)

    Frías-Espericueta, M G; Mejía-Cruz, R; Osuna López, I; Muy-Rangel, M D; Rubio-Carrasco, W; Aguilar-Juárez, M; Voltolina, D

    2014-02-01

    The aim of this work was to survey the discharges of dissolved and particulate Cd, Cu, Fe, Mn, Pb and Zn of the eight main rivers of Sinaloa State to the Mexican coastal environment. Zn was the most abundant dissolved metal and Fe was the most abundant particulate (8.02-16.90 and 51.8-1,140.3 μg/L, respectively). Only particulate Mn had significantly (p = 0.028) higher values in summer-fall (rainy season), whereas the significantly (p = 0.036) higher values of dissolved Zn were observed in winter and spring. The highest annual total discharges to Sinaloa coastal waters were those of the rivers San Lorenzo and Piaxtla (>2 × 10(3) m.t.) and the lowest those of rivers Baluarte and El Fuerte (349 and 119 m.t., respectively). Pb concentrations may become of concern, because they are higher than the value recommended for the welfare of aquatic communities of natural waters.

  19. Gulf of Mexico Coastal Ocean Observing System: The Gulf Component of the U.S. Integrated Ocean Observing System

    Science.gov (United States)

    Bernard, L. J.; Moersdorf, P. F.

    2005-05-01

    The United States is developing an Integrated Ocean Observing System (IOOS) as the U.S. component of the international Global Ocean Observing System (GOOS). IOOS consists of: (1) a coastal observing system for the U.S. EEZ, estuaries, and Great Lakes; and (2) a contribution to the global component of GOOS focused on climate and maritime services. The coastal component will consist of: (1) a National Backbone of observations and products from our coastal ocean supported by federal agencies; and (2) contributions of Regional Coastal Ocean Observing Systems (RCOOS). The Gulf of Mexico Coastal Ocean Observing System (GCOOS) is one of eleven RCOOS. This paper describes how GCOOS is progressing as a system of systems to carry out data collection, analysis, product generation, dissemination of information, and data archival. These elements are provided by federal, state, and local government agencies, academic institutions, non-government organization, and the private sector. This end-to-end system supports the seven societal goals of the IOOS, as provided by the U.S. Commission on Ocean Policy: detect and forecast oceanic components of climate variability, facilitate safe and efficient marine operations, ensure national security, manage marine resources, preserve and restore healthy marine ecosystems, mitigate natural hazards, and ensure public health. The initial building blocks for GCOOS include continuing in situ observations, satellite products, models, and other information supported by federal and state government, private industry, and academia. GCOOS has compiled an inventory of such activities, together with descriptions, costs, sources of support, and possible out-year budgets. These activities provide information that will have broader use as they are integrated and enhanced. GCOOS has begun that process by several approaches. First, GCOOS has established a web site (www.gcoos.org) which is a portal to such activities and contains pertinent information

  20. The role of evapotranspiration in the groundwater hydrochemistry of an arid coastal wetland (Península Valdés, Argentina)

    International Nuclear Information System (INIS)

    Alvarez, María del Pilar; Carol, Eleonora; Dapeña, Cristina

    2015-01-01

    Coastal wetlands are complex hydrogeological systems, in which saline groundwater usually occurs. Salinity can be attributed to many origins, such as dissolution of minerals in the sediments, marine contribution and evapotranspiration, among others. The aim of this paper is to evaluate the processes that condition the hydrochemistry of an arid marsh, Playa Fracasso, located in Patagonia, Argentina. A study of the dynamics and geochemistry of the groundwater was carried out in each hydrogeomorphological unit, using major ion and isotope ( 18 O and 2 H) data, soil profiles descriptions and measurements, and recording of water tables in relation to the tidal flow. Water balances and analytical models based on isotope data were used to quantify the evaporation processes and to define the role of evaporation in the chemical composition of water. The results obtained show that the groundwater salinity of the marsh comes mainly from the tidal inflow, to which the halite and gypsum dissolution is added. These mineral facies are the result of the total evaporation of the marine water flooding that occurs mostly at the spring high tides. The isotope relationships in the fan and bajada samples show the occurrence of evaporation processes. Such processes, however, are not mainly responsible for the saline content of groundwater, which is actually generated by the dissolution of the typical evaporite facies of the arid environment sediments. It is concluded that the evapotranspiration processes condition groundwater quality. This is not only due to the saline enrichment caused by the evapotranspiration of shallow water, but also because such processes are the main drivers of the formation of soluble salts, which are then incorporated into the water by groundwater or tidal flow. - Highlights: • Tidal inflow and evapotranspiration processes condition the salinity of the marsh. • The total evaporation of marine water led the halite and gypsum precipitation. • The dissolution

  1. No association between the use of Bti for mosquito control and the dynamics of non-target aquatic invertebrates in French coastal and continental wetlands.

    Science.gov (United States)

    Lagadic, Laurent; Schäfer, Ralf B; Roucaute, Marc; Szöcs, Eduard; Chouin, Sébastien; de Maupeou, Jérôme; Duchet, Claire; Franquet, Evelyne; Le Hunsec, Benoit; Bertrand, Céline; Fayolle, Stéphanie; Francés, Benoît; Rozier, Yves; Foussadier, Rémi; Santoni, Jean-Baptiste; Lagneau, Christophe

    2016-05-15

    The environmental safety of Bacillus thuringiensis subsp. israelensis (Bti) is still controversial, mainly because most of the previous field studies on its undesired effects were spatially limited and did not address the relationship between community similarity and application time and frequency. No general statement can therefore be drawn on the usage conditions of Bti that insure protection of non-target organisms. The present study was conducted in eight sites distributed over the main geographical sectors where mosquito control is implemented in mainland France and Corsica. Changes in non-target aquatic invertebrates were followed at elapsed time after repeated applications of two Bti formulations (VectoBac® WDG or 12AS) up to four consecutive years. We examined the influence of both larvicide treatments and environmental variables on community dynamics and dissimilarity between treated and control areas. As it can be argued that chironomids are the most vulnerable group of non-target invertebrates, we scrutinised potential Bti-related effects on the dynamics of their community. The use of VectoBac® WDG and 12AS in coastal and continental wetlands had no immediate or long-term detectable effect on the taxonomic structure and taxa abundance of non-target aquatic invertebrate communities, including chironomids. This applied to the main habitats where mosquito larvae occur, regardless of their geographic location. Flooding, whose frequency and duration depend on local meteorological and hydrological conditions, was identified as the main environmental driver of invertebrate community dynamics. Our findings add support to the environmental safety of currently available Bti formulations when following recommended application rates and best mosquito control practices. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Hurricane Ingrid and Tropical Storm Hanna's effects on the salinity of the coastal aquifer, Quintana Roo, Mexico

    Science.gov (United States)

    Kovacs, Shawn E.; Reinhardt, Eduard G.; Stastna, Marek; Coutino, Aaron; Werner, Christopher; Collins, Shawn V.; Devos, Fred; Le Maillot, Christophe

    2017-08-01

    There is a lack of information on aquifer dynamics in anchialine systems, especially in the Yucatán Peninsula of Mexico. Most of our knowledge is based on ;spot; measurements of the aquifer with no long-term temporal monitoring. In this study spanning four years (2012-2016), sensors (water depth and conductivity (salinity)) were deployed and positioned (-9 and -10 m) in the meteoric Water Mass (WM) close to the transition with the marine WM (halocline) in 2 monitoring sites within the Yax Chen cave system to investigate precipitation effects on the salinity of the coastal aquifer. The results show variation in salinity (95 mm) such as Hurricane Ingrid (2013) and Tropical Storm Hanna (2014) shows meteoric water mass salinity rapidly increasing (approx. 6.39 to >8.6 ppt), but these perturbations have a shorter duration (weeks and days). Wavelet analysis of the salinity record indicates seasonal mixing effects in agreement with the wet and dry periods, but also seasonal effects of tidal mixing (meteoric and marine water masses) occurring on shorter time scales (diurnal and semi-diurnal). These results demonstrate that the salinity of the freshwater lens is influenced by precipitation and turbulent mixing with the marine WM. The salinity response is scaled with precipitation; larger more intense rainfall events (>95 mm) create a larger response in terms of the magnitude and duration of the salinity perturbation (>1 ppt). The balance of precipitation and its intensity controls the temporal and spatial patterning of meteoric WM salinity.

  3. Microbial nitrogen sinks in the water column of a large coastal hypoxic area, the Gulf of Mexico "Dead Zone"

    Science.gov (United States)

    Rogener, M. K.; Roberts, B. J.; Rabalais, N. N.; Stewart, F. J.; Joye, S. B.

    2016-02-01

    Excess nitrogen in coastal environments leads to eutrophication, harmful algal blooms, habitat loss, oxygen depletion and reductions in biodiversity. As such, biological nitrogen (N) removal through the microbially-mediated process of denitrification is a critical ecosystem function that can mitigate the negative consequences of excess nitrogen loading. However, denitrification can produce nitrous oxide, a potent greenhouse gas, as a byproduct under some environmental conditions. To understand how excess nitrogen loading impacts denitrification, we measured rates of this process in the water column of the Gulf of Mexico "Dead Zone" three times over the summer of 2015. The Dead Zone is generated by excessive nitrogen loading from the Mississippi River co-occurring with strong water column stratification, which leads to a large summer-time hypoxic/anoxic area at the mouth of the river and along the coast of Louisiana. Rates of denitrification ranged from 31 to 153 nmol L-1 d-1. Dead Zone waters are also enriched in methane and aerobic methane oxidation rates ranged from 0.1 to 4.3 nmol L-1 d-1. Maximal denitrification rates were observed at stations with the lowest oxygen concentrations and highest methane oxidation rates, suggesting a potential coupling between nitrate reduction and methane oxidation which both scrubs reactive N and methane from the system, thus performing a duel ecosystem service.

  4. Toxicities of sediments below 10 effluent outfalls to near-coastal areas of the Gulf of Mexico

    International Nuclear Information System (INIS)

    Lewis, M.; Weber, D.; Stanley, R.

    1995-01-01

    The chemical quality and toxicities of sediments collected in the receiving waters below 10 wastewater outfalls to Northwest Florida coastal areas were evaluated at multiple stations during 1994--1996. Eight types of toxicity tests using 11 test species were used to assess acute and chronic toxicity of the sediments collected below industrial, municipal, power generation and pulp mill outfalls. The primary objectives of the study were to evaluate the relative ability of different assessment procedures to detect toxicity and to provide some much-needed perspective on the impact of major point sources on sediment quality in Gulf of Mexico estuaries. The major chemical contaminants were heavy metals and PAHs. Acute and chronic toxicities were noted. Results of tests with sediment collected at the same location but several months later often differed. The most sensitive species were mysids and an estuarine amphipod. The least sensitive species were fish and macrophyte seedlings. There was poor correlation of effluent toxicity to sediment toxicity in the receiving water. Toxicity of the effluents was greater than that of the sediments. Overall, the unavailability of relevant chronic toxicity methods, uncertain criteria for choice of control stations, lack of guidance on frequency of testing and the dynamic physical and chemical characteristics of sediments are factors that need consideration if sediment monitoring is to be part of the NPDES regulatory process

  5. Landscape changes in a coastal system undergoing tourism development: implications for Barra de Navidad Lagoon, Jalisco, Mexico

    Directory of Open Access Journals (Sweden)

    Tara L. Holland

    2012-02-01

    Full Text Available In this study, changes in land cover and land use patterns that occurred between 1985 and 2000 in the surrounding basin of the Barra de Navidad coastal lagoon in Jalisco, Mexico are quantified and explained. Two satellite images from 1985 (Landsat TM and 2000 (Landsat ETM+ were analyzed with supervised classification and ground truthing to evaluate changes in six land use/cover categories: lagoon, agriculture, urban/tourist, tropical dry forest, mangrove and bare substratum. Changes in land use composition were evaluated using a transition matrix and changes to configuration were interpreted using landscape metrics. Results show that urban and tourist areas expanded between 1985 and 2000, mostly at the expense of forested and bare land. Mangroves showed a large relative decrease in area (-39% and experienced fragmentation. These changes appear to be related to increased sedimentation a fan progradation into Barra de Navidad lagoon. These results may serve as a model for comparison in other systems experiencing multiple stressors, especially changes related to tourism and the intensification of resource extraction.

  6. Executive summary - Geologic assessment of coal in the Gulf of Mexico coastal plain, U.S.A.

    Science.gov (United States)

    Warwick, Peter D.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.

    2011-01-01

    The National Coal Resource Assessment (NCRA) project of the U.S. Geological Survey (USGS) has assessed the quantity and quality of the nation's coal deposits that potentially could be mined during the next few decades. For eight years, geologic, geochemical, and resource information was collected and compiled for the five major coal-producing regions of the United States: the Appalachian Basin, Illinois Basin, Northern Rocky Mountains and Great Plains, Colorado Plateau, and the western part of the Gulf of Mexico Coastal Plain (Gulf Coast) region (Figure 1). In particular, the NCRA assessed resource estimates, compiled coal-quality information, and characterized environmentally sensitive trace elements, such as arsenic and mercury, that are mentioned in the 1990 Clean Air Act Amendments (U.S. Environmental Protection Agency, 1990). The results of the USGS coal assessment efforts may be found at: http://energy.cr.usgs.gov/coal/coal-assessments/index.html and a summary of the results from all assessment areas can be found in Ruppert et al. (2002) and Dennen (2009).Detailed assessments of the major coal-producing areas for the Gulf Coast region along with reviews of the stratigraphy, coal quality, resources, and coalbed methane potential of the Cretaceous, Paleocene, and Eocene coal deposits are presented in this report (Chapters 5-10).

  7. Natural Recovery and Planned Intervention in Coastal Wetlands: Venice Lagoon (Northern Adriatic Sea, Italy as a Case Study

    Directory of Open Access Journals (Sweden)

    Chiara Facca

    2014-01-01

    Full Text Available The goals of conservation and sustainable use of environmental ecosystems have increased the need for detailed knowledge of ecological evolution and responses to both anthropogenic pressures and recovery measures. The present study shows the effects of natural processes and planned intervention in terms of reducing nutrient inputs in a highly exploited coastal lagoon, describing its evolution over a 16-year period from the late 1980s (when eutrophication was at its peak until 2003. Changes in nutrient and carbon concentrations in the top layer of sediments were investigated in parallel with macroalgal and seagrass biomass in the most anthropized basin of Venice Lagoon in four surveys conducted in accordance with the same protocols in 1987, 1993, 1998, and 2003. A pronounced reduction in trophic state (mainly total nitrogen, organic phosphorus, and organic carbon concentrations and macroalgal biomass was recorded, together with the progressive expansion of seagrass meadows. General considerations are also made on the effects of Manila clam farming and the shift from illegal to managed clam farming.

  8. Natural recovery and planned intervention in coastal wetlands: Venice Lagoon (northern Adriatic Sea, Italy) as a case study.

    Science.gov (United States)

    Facca, Chiara; Ceoldo, Sonia; Pellegrino, Nicola; Sfriso, Adriano

    2014-01-01

    The goals of conservation and sustainable use of environmental ecosystems have increased the need for detailed knowledge of ecological evolution and responses to both anthropogenic pressures and recovery measures. The present study shows the effects of natural processes and planned intervention in terms of reducing nutrient inputs in a highly exploited coastal lagoon, describing its evolution over a 16-year period from the late 1980s (when eutrophication was at its peak) until 2003. Changes in nutrient and carbon concentrations in the top layer of sediments were investigated in parallel with macroalgal and seagrass biomass in the most anthropized basin of Venice Lagoon in four surveys conducted in accordance with the same protocols in 1987, 1993, 1998, and 2003. A pronounced reduction in trophic state (mainly total nitrogen, organic phosphorus, and organic carbon concentrations) and macroalgal biomass was recorded, together with the progressive expansion of seagrass meadows. General considerations are also made on the effects of Manila clam farming and the shift from illegal to managed clam farming.

  9. Coastal circulation and hydrography in the Gulf of Tehuantepec, Mexico, during winter

    Science.gov (United States)

    Barton, E. D.; Lavín, M. F.; Trasviña, A.

    2009-02-01

    Winter observations of shelf and slope hydrography and currents in the inner Gulf of Tehuantepec are analysed from two field studies in 1989 and 1996 to specify the variability of near-shore conditions under varying wind stress. During the winter period frequent outbursts of 'Norte' winds over the central Gulf result in persistent alongshore inflows along both its eastern and western coasts. Wind-induced variability on time scales of several days strongly influences the shelf currents, but has greater effect on its western coast because of the generation and separation of anticyclonic eddies there. The steadier inflow (˜0.2 m s -1) on the eastern shelf is evident in a strong down-bowing of shallow isosurfaces towards the coast within 100 km of shore, below a wedge of warmer, fresher and lighter water. This persistent entry of less saline (33.4-34.0), warmer water from the southeast clearly originates in buoyancy input by rivers along the Central American coast, but is augmented by a general shoreward tendency (0.2 m s -1) in the southeastern Gulf. The resultant shallow tongue of anomalous water is generally swept offshore in the head of the Gulf and mixed away by the strong outflow and vertical overturning of the frequent 'Norte' events but during wind relaxations the warm, low-salinity coastal flow may briefly extend further west. In the head of the Gulf, flow is predominantly offshore (depression, respectively, of the pycnocline against the shore. More saline, open ocean water is introduced from the north-western side of the Gulf by the inflow along the west coast. During extended wind relaxations, the flow becomes predominantly eastward beyond the shelf while nearshore the coastally trapped buoyant inflow from the southeast penetrates across the entire head of the gulf at least as far as its western limit. On the basis of these and other recent observations, it seems that the accepted view of a broad, persistent Costa Rica Coastal Current (CRCC) is the result

  10. Lead from hunting activities and its potential environmental threat to wildlife in a protected wetland in Yucatan, Mexico.

    Science.gov (United States)

    Arcega-Cabrera, Flor; Noreña-Barroso, Elsa; Oceguera-Vargas, Ismael

    2014-02-01

    This study provides insights into the status of lead in the protected wetland of El Palmar, located on the northwestern littoral of the Yucatan Peninsula. This reserve is ecologically and economically important because it provides feeding and breeding habitats for many species, as well as being an ecotourism destination (especially for bird watching). Although it is a protected area, duck species are heavily hunted within the reserve during the winter. As a result, animals feeding or living in sediments could be exposed to anthropogenic lead. Total lead and its geochemical fractionated forms were measured in sediment cores from six selected sites in "El Palmar" wetland, during pre- and post-hunting seasons, to approximate the potential environmental threat (especially for benthonic living/feeding organisms). Anthropogenic lead concentrations detected in soil cores ranged from below the minimum infaunal community effect level (30.24 μg g(-1)) during the pre-hunting season, to bordering the probable infaunal community effect level (112.18 μg g(-1)) during the post-hunting season, according to SquiiRTs NOAA guidelines. Yet, these results were lower than expected based on the intensity of hunting. Consequently, this article explores the possibility that the lower than expected lead concentration in sediments results from (1) degradation of shot and transformation to soluble or particulate forms; or (2) ingestion of lead shot by benthic and other lacustrine species living in the protected area. Geochemical fractionation of lead demonstrated that in the top 6 cm of the soil column at heavily active hunting sites (EP5 and EP6), lead was associated with the lithogenic fraction (average 45 percent) and with the organic fraction (average 20 percent). Bioavailable lead (sum of lead adsorbed to the carbonates, Fe/Mn oxyhydroxides and organic fractions) in sediments was lower than 50 percent for the heavily active hunting areas and higher for the rest of the sites

  11. Pre-Construction Biogeochemical Analysis of Mercury in Wetlands Bordering the Hamilton Army Airfield (HAAF) Wetlands Restoration Site. Part 2

    National Research Council Canada - National Science Library

    Best, Elly P; Fredrickson, Herbert L; Hintelmann, Holger; Clarisse, Olivier; Dimock, Brian; Lutz, Charles H; Lotufo, Gui R; Millward, Rod N; Bednar, Anthony J; Furey, John S

    2007-01-01

    ...) is working with the San Francisco Basin Regional Water Board, California State Coastal Conservancy, and San Francisco Bay Conservation and Development Commission to reconstruct wetlands at the former...

  12. Metazoan parasites of fishes from the Celestun coastal lagoon, Yucatan, Mexico.

    Science.gov (United States)

    Sosa-Medina, Trinidad; Vidal-Martínez, Víctor M; Aguirre-Macedo, M Leopoldina

    2015-08-31

    The aims of this study were to produce a checklist of the metazoan parasites of fishes from the Celestun coastal lagoon and to determine the degree of faunal similarity among the fishes based on the metazoan parasites they share. A checklist was prepared including all available records (1996-2014) of parasites of marine, brackish water and freshwater fishes of the area. All of these data were included in a presence/absence database and used to determine similarity via Jaccard's index. The results indicate the presence of 62 metazoan parasite species infecting 22 fish species. The number of metazoan parasite species found in the fishes from the Celestún lagoon is apparently the highest reported worldwide for a tropical coastal lagoon. The parasites included 12 species of adult digeneans, 27 digeneans in the metacercarial stage, 6 monogeneans, 3 metacestodes, 9 nematodes, 2 acanthocephalans, 2 crustaceans and 1 annelid. Forty parasite species were autogenic and 23 were allogenic and 1 unknown. The overall similarity among all of the species of fish with respect to the metazoan parasites they share was low (0.08 ± 0.12), with few similarity values above 0.4 being obtained. This low similarity was due primarily to the presence of suites of parasites exclusive to specific species of fish. The autogenic component of the parasite fauna (40 species) dominated the allogenic component (21 species). The most likely explanation for the large number of fish parasites found at Celestún is the good environmental condition of the lagoon, which allows the completion of parasite life cycles and free circulation of euryhaline fishes from the marine environment bringing marine parasites into the lagoon.

  13. The effects of landscape position on plant species density: Evidence of past environmental effects in a coastal wetland

    Science.gov (United States)

    Grace, J.B.; Guntenspergen, G.R.

    1999-01-01

    Here we propose that an important cause of variation in species density may be prior environmental conditions that continue to influence current patterns. In this paper we investigated the degree to which species density varies with location within the landscape, independent of contemporaneous environmental conditions. The area studied was a coastal marsh landscape subject to periodic storm events. To evaluate the impact of historical effects, it was assumed that the landscape position of a plot relative to the river's mouth ('distance from sea') and to the edge of a stream channel ('distance from shore') would correlate with the impact of prior storm events, an assumption supported by previous studies. To evaluate the importance of spatial location on species density, data were collected from five sites located at increasing distances from the river's mouth along the Middle Pearl River in Louisiana. At each site, plots were established systematically along transects perpendicular to the shoreline. For each of the 175 Plots, we measured elevation, soil salinity, percent of plot recently disturbed, percent of sunlight captured by the plant canopy (as a measure of plant abundance), and plant species density. Structural equation analysis ascertained the degree to which landscape position variables explained variation in species density that could not be explained by current environmental indicators. Without considering landscape variables, 54% of the variation in species density could be explained by the effects of salinity, flooding, and plant abundance. When landscape variables were included, distance from shore was unimportant but distance from sea explained an additional 12% of the variance in species density (R2 of final model = 66%). Based on these results it appears that at least some of the otherwise unexplained variation in species density can be attributed to landscape position, and presumably previous storm events. We suggest that future studies may gain

  14. Winter climate change and coastal wetland foundation species: salt marshes vs. mangrove forests in the southeastern United States.

    Science.gov (United States)

    Osland, Michael J; Enwright, Nicholas; Day, Richard H; Doyle, Thomas W

    2013-05-01

    We live in an era of unprecedented ecological change in which ecologists and natural resource managers are increasingly challenged to anticipate and prepare for the ecological effects of future global change. In this study, we investigated the potential effect of winter climate change upon salt marsh and mangrove forest foundation species in the southeastern United States. Our research addresses the following three questions: (1) What is the relationship between winter climate and the presence and abundance of mangrove forests relative to salt marshes; (2) How vulnerable are salt marshes to winter climate change-induced mangrove forest range expansion; and (3) What is the potential future distribution and relative abundance of mangrove forests under alternative winter climate change scenarios? We developed simple winter climate-based models to predict mangrove forest distribution and relative abundance using observed winter temperature data (1970-2000) and mangrove forest and salt marsh habitat data. Our results identify winter climate thresholds for salt marsh-mangrove forest interactions and highlight coastal areas in the southeastern United States (e.g., Texas, Louisiana, and parts of Florida) where relatively small changes in the intensity and frequency of extreme winter events could cause relatively dramatic landscape-scale ecosystem structural and functional change in the form of poleward mangrove forest migration and salt marsh displacement. The ecological implications of these marsh-to-mangrove forest conversions are poorly understood, but would likely include changes for associated fish and wildlife populations and for the supply of some ecosystem goods and services. © 2012 Blackwell Publishing Ltd.

  15. Mexico.

    Science.gov (United States)

    1993-01-01

    The background notes on Mexico provide text and recent statistical information on the geography, population, government, economy, and foreign relations, specifically the North American Free Trade Agreement with US. The 1992 population is estimated at 89 million of which 60% are mestizo (Indian-Spanish), 30% are American Indian, 9% are Caucasian, and 1% are other. 90% are Roman Catholic. There are 8 years of compulsory education. Infant mortality is 30/1000 live births. Life expectancy for males is 68 years and 76 years for females. The labor force is comprised of 30% in services, 24% in agriculture and fishing, 19% in manufacturing, 13% in commerce, 7% in construction, 4% in transportation and communication, and .4% in mining. There are 31 states and a federal district. Gross domestic product (GDP) per capita was $3200 in 1991. Military expenditures were .5% of GDP in 1991. The average inflation rate is 19%. Mexico City with 20 million is the largest urban center in the world. In recent years, the economy has been restructured with market oriented reforms; the result has been a growth of GDP of 3.6% in 1991 from 2% in 1987. Dependence on oil exports has decreased. There has been privatization and deregulation of state-owned companies. Subsidies to inefficient companies have been stopped. Tariff rates were reduced. The financial debt has been reduced and turned into a surplus of .8% in 1992. Mexico's foreign debt has been reduced from its high in 1987 of $107 billion. Agricultural reforms have been ongoing for 50 years. Land was redistributed, but standards of living and productivity have improved only slightly. Rural land tenure regulations have been changed, and other economic reforms are expected. Mexico engages in ad hoc international groups and is selective about membership in international organizations.

  16. Physiological response curves reveal differences among season advancement and timing of grazing experimental treatments in a coastal Alaskan wetland

    Science.gov (United States)

    Leffler, A. J.; Kelsey, K.; Beard, K. H.; Choi, R. T.; Welker, J. M.

    2016-12-01

    The phenology of northern ecosystems is rapidly changing as high latitude regions warm. Spring green-up has advanced 1-3 days per decade since the early 1980's and sea ice retreat is likely to further accelerate the arrival of spring in coastal Alaska. One result of spring advancement is a phenological mismatch with the arrival of migratory geese that bread in the region. As green-up advances, geese arrive into a phenologically older system where vegetation has a higher C:N ratio than younger grasses with potential consequences for goose nutrition and C and N cycling. In 2014 and 2015 we established a season advancement X timing of grazing experiment to examine the ecosystem consequences of this mismatch. We used a LI-Cor 8100 automated, chamber-based C flux system to monitor hourly net ecosystem exchange (NEE) in eight plots: four were warmed in June to advance the growing season, four received ambient temperatures; two each experienced early, typical, late, or no grazing. The experiment is replicated six times, but the automated system is capable of measuring only one block; other blocks are measured twice weekly with a portable system. We fit physiological light response curves to weekly data and used incident sunlight to estimate daily NEE. Results suggest that daily carbon uptake ranged from ca. 0.6 to 4.5 g m-2 d-1 in the different treatments. Carbon uptake in the season advancement plots was lower than in the ambient plots by ca. 0.5 g m-2 d-1 averaged during the summer. Delaying grazing into the later season, the expectation of climate change, greatly increased NEE to 4.5 g m-2 d-1, a value much greater than the typical grazing period in 2015. Completely eliminating grazing from the system resulted in NEE of 2.9 g m-2 d-1. Differences were likely driven by warmer soils enhancing respiration, removal of photosynthetic biomass, and grazing maintaining tissue in a young, highly photosynthetic form. Overall our results suggest that timing of grazing in the

  17. Using ecotechnology to address water quality and wetland habitat loss problems in the Mississippi basin: a hierarchical approach.

    Science.gov (United States)

    Day, John W; Yañéz Arancibia, Alejandro; Mitsch, William J; Lara-Dominguez, Ana Laura; Day, Jason N; Ko, Jae-Young; Lane, Robert; Lindsey, Joel; Lomeli, David Zarate

    2003-12-01

    Human activities are affecting the environment at continental and global scales. An example of this is the Mississippi basin where there has been a large scale loss of wetlands and water quality deterioration over the past century. Wetland and riparian ecosystems have been isolated from rivers and streams. Wetland loss is due both to drainage and reclamation, mainly for agriculture, and to isolation from the river by levees, as in the Mississippi delta. There has been a decline in water quality due to increasing use of fertilizers, enhanced drainage and the loss of wetlands for cleaning water. Water quality has deteriorated throughout the basin and high nitrogen in the Mississippi river is causing a large area of hypoxia in the Gulf of Mexico adjacent to the Mississippi delta. Since the causes of these problems are distributed over the basin, the solution also needs to be distributed over the basin. Ecotechnology and ecological engineering offer the only ecologically sound and cost-effective method of solving these problems. Wetlands to promote nitrogen removal, mainly through denitrification but also through burial and plant uptake, offer a sound ecotechnological solution. At the level of the Mississippi basin, changes in farming practices and use of wetlands for nitrogen assimilation can reduce nitrogen levels in the River. There are additional benefits of restoration of wetland and riverine ecosystems, flood control, reduction in public health threats, and enhanced wildlife and fisheries. At the local drainage basin level, the use of river diversions in the Mississippi delta can address both problems of coastal land loss and water quality deterioration. Nitrate levels in diverted river water are rapidly reduced as water flows through coastal watersheds. At the local level, wetlands are being used to treat municipal wastewater. This is a cost-effective method, which results in improved water quality, enhanced wetland productivity and increased accretion. The

  18. Observations of inner shelf cross-shore surface material transport adjacent to a coastal inlet in the northern Gulf of Mexico

    Science.gov (United States)

    Roth, Mathias K.; MacMahan, Jamie; Reniers, Ad; Özgökmen, Tamay M.; Woodall, Kate; Haus, Brian

    2017-04-01

    Motivated by the Deepwater Horizon oil spill, the Surfzone and Coastal Oil Pathways Experiment obtained Acoustic Doppler Current Profiler (ADCP) Eulerian and GPS-drifter based Lagrangian "surface" (Mexico to describe the influence of small-scale river plumes on surface material transport pathways in the nearshore. Lagrangian paths are qualitatively similar to surface pathlines derived from non-traditional, near-surface ADCP velocities, but both differ significantly from depth-averaged subsurface pathlines. Near-surface currents are linearly correlated with wind velocities (r =0.76 in the alongshore and r =0.85 in the cross-shore) at the 95% confidence level, and are 4-7 times larger than theoretical estimates of wind and wave-driven surface flow in an un-stratified water column. Differences in near-surface flow are attributed to the presence of a buoyant river plume forced by winds from passing extratropical storms. Plume boundary fronts induce a horizontal velocity gradient where drifters deployed outside of the plume in oceanic water routinely converge, slow, and are re-directed. When the plume flows west parallel to the beach, the seaward plume boundary front acts as a coastal barrier that prevents 100% of oceanic drifters from beaching within 27 km of the inlet. As a result, small-scale, wind-driven river plumes in the northern Gulf of Mexico act as coastal barriers that prevent offshore surface pollution from washing ashore west of river inlets.

  19. Exploring the controls of soil biogeochemistry in a restored coastal wetland using object-oriented computer simulations of uptake kinetics and thermodynamic optimization in batch reactors

    Science.gov (United States)

    Payn, R. A.; Helton, A. M.; Poole, G.; Izurieta, C.; Bernhardt, E. S.; Burgin, A. J.

    2012-12-01

    Many hypotheses have been proposed to predict patterns of biogeochemical redox reactions based on the availability of electron donors and acceptors and the thermodynamic theory of chemistry. Our objective was to develop a computer model that would allow us to test various alternatives of these hypotheses against data gathered from soil slurry batch reactors, experimental soil perfusion cores, and in situ soil profile observations from the restored Timberlake Wetland in coastal North Carolina, USA. Software requirements to meet this objective included the ability to rapidly develop and compare different hypothetical formulations of kinetic and thermodynamic theory, and the ability to easily change the list of potential biogeochemical reactions used in the optimization scheme. For future work, we also required an object pattern that could easily be coupled with an existing soil hydrologic model. These requirements were met using Network Exchange Objects (NEO), our recently developed object-oriented distributed modeling framework that facilitates simulations of multiple interacting currencies moving through network-based systems. An initial implementation of the object pattern was developed in NEO based on maximizing growth of the microbial community from available dissolved organic carbon. We then used this implementation to build a modeling system for comparing results across multiple simulated batch reactors with varied initial solute concentrations, varied biogeochemical parameters, or varied optimization schemes. Among heterotrophic aerobic and anaerobic reactions, we have found that this model reasonably predicts the use of terminal electron acceptors in simulated batch reactors, where reactions with higher energy yields occur before reactions with lower energy yields. However, among the aerobic reactions, we have also found this model predicts dominance of chemoautotrophs (e.g., nitrifiers) when their electron donor (e.g., ammonium) is abundant, despite the

  20. The polycyclic aromatic hydrocarbon degradation potential of Gulf of Mexico coastal microbial communities after the Deepwater Horizon oil spill

    Directory of Open Access Journals (Sweden)

    Anthony D. Kappell

    2014-05-01

    Full Text Available The Deepwater Horizon (DWH blowout resulted in oil transport, including polycyclic aromatic hydrocarbons (PAHs to the Gulf of Mexico shoreline. The microbial communities of these shorelines are thought to be responsible for the intrinsic degradation of PAHs. To investigate the Gulf Coast beach microbial community response to hydrocarbon exposure, we examined the functional gene diversity, bacterial community composition, and PAH degradation capacity of a heavily oiled and non-oiled beach following the oil exposure. With a non-expression functional gene microarray targeting 539 gene families, we detected 28,748 coding sequences. Of these sequences, 10% were uniquely associated with the severely oil-contaminated beach and 6.0% with the non-oiled beach. There was little variation in the functional genes detected between the two beaches; however the relative abundance of functional genes involved in oil degradation pathways, including PAHs, were greater in the oiled beach. The microbial PAH degradation potentials of both beaches, were tested in mesocosms. Mesocosms were constructed in glass columns using sands with native microbial communities, circulated with artificial sea water and challenged with a mixture of PAHs. The low-molecular weight PAHs, fluorene and naphthalene, showed rapid depletion in all mesocosms while the high-molecular weight benzo[α]pyrene was not degraded by either microbial community. Both the heavily oiled and the non-impacted coastal communities showed little variation in their biodegradation ability for low molecular weight PAHs. Massively-parallel sequencing of 16S rRNA genes from mesocosm DNA showed that known PAH degraders and genera frequently associated with oil hydrocarbon degradation represented a major portion of the bacterial community. The observed similar response by microbial communities from beaches with a different recent history of oil exposure suggests that Gulf Coast beach communities are primed for PAH

  1. Analyzing anthropogenic pressures in soils of agro-ecological protected coastal wetlands in L'Albufera de Valencia Natural Park, Spain

    Science.gov (United States)

    Pascual-Aguilar, Juan Antonio; Andreu, Vicente; Gimeno, Eugenia; Picó, Yolanda

    2013-04-01

    Coastal wetlands, despite the importance of their environmental and ecological functions, are areas that suffer of great pressures. Most of them are produced by the rapid development of the surrounding artificial landscapes. Socio-economic factors such as population growth and urban-industrial surfaces expansion introduce pressures on the nearby environment affecting the quality of natural and agricultural landscapes. The present research analyses interconnections among landscapes (urban, agricultural and natural) under the hypothesis that urban-artificial impacts could be detected on soils of an agro-ecological protected area, L'Albufera de Valencia, Natural Park, located in the vicinity or the urban area of the City of Valencia, Spain. It has been developed based on Environmental Forensics criteria witch attend two types of anthropogenic pressures: (1) direct, due to artificialization of soil covers that produce anthropogenic soil sealing, and (2) indirect, which are related to water flows coming from urban populations throw artificial water networks (sewage and irrigation systems) and that ultimately will be identified by the presence of o emerging-pharmaceuticals contaminants in soils of the protected area. For the first case, soil sealing a methodology based on temporal comparison of two digital layers for the years 1991 and 2011 applying Geographical Information Systems and Landscapes Metrics were undertaken. To determine presence of emerging contaminants 15 soil samples within the Natural Park were analyzed applying liquid chromatography tandem mass spectrometry for the detection of 17 pharmaceutical compounds. Results show that both processes are present in the Natural Park with a clear geographical pattern. Either soil sealing or detection of pharmaceuticals are more intensive in the northern part of the study area. This is related to population density (detection of pharmaceuticals) and land cover conversion from agricultural and natural surfaces to

  2. In the Land of the Sky: Recent Paleoenvironmental Research From Coastal Oaxaca, Mexico

    Science.gov (United States)

    Goman, M. F.; Joyce, A. A.; Mueller, R. G.

    2005-05-01

    The Lower Río Verde Valley of Oaxaca has had a long and complex cultural history in part shaped by significant landscape change that ocurred 2300 years ago, when the Río Verde river changed morphology from a meandering to a braided form. These changes were precipitated by anthropogenic landuse impacts in the highland valleys of Oaxaca over 125 linear km to the north. While the lower valley's geomorphic history is well studied, little is known of its paleoecology. In order to reconstruct the history of vegetation, climate, and associated land use change, sediment cores were raised from several sites throughout the region. We present stratigraphical, palynological, and charcoal data from three sites in the region. The lower drainage basin consists entirely of the Verde's coastal valley. The climate of the lower Río Verde Valley is hot and humid with mean annual rainfall of 1000 mm to 2000 mm and average temperatures range from 25°C to 28°C. We discuss the pollen and stratigraphic record from Laguna Pastoría which is a brackish estuary protected from the Pacific Ocean by a roughly east-west trending bay barrier. The bay barrier is about 500 m wide and 2 to 4 m high. Low scrub vegetation (cacti, thorny bushes, small trees and palms) grow on the barrier. The lagoon itself is approximately 9 km long and varies in depth with a 3-4 m maximum. Tides are microtidal (1 m). The lagoon supports a diverse array of mangroves (Rhizophora mangle, Laguncularia racemosa, Conocarpus erectus and Avicennia germinans). Two sediment cores were raised from the lagoon (LP1 and LP2) and provide a record of hurricane strikes and possible changes in the frequency of El Niño's. The LP1 core covers approximately the last 5000 yrs. Preliminary pollen analysis indicates that pollen is in excellent condition and is diverse (>60 taxa). Zea mays pollen was identified from sediments dating to the early Formative period (~ 3600 yr ago). The charcoal records analyzed from 2 paleomeanders of the

  3. 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

  4. Mexico

    International Nuclear Information System (INIS)

    2003-06-01

    This document summarizes the key energy data for Mexico: 1 - energy organizations and policy: Ministry of energy (SENER), Comision Reguladora de Energia (CRE), Ministry of Finances, Ministry of trade and industrial development (SECOFI), national commission for energy savings (CONAE); 2 - companies: federal commission of electricity (CFE), Minera Carbonifera Rio Escondido (MICARE - coal), Pemex (petroleum); 3 - energy production: resources, electric power, petroleum, natural gas; 4 - energy consumption; 5 - stakes and perspectives. Some economic and energy indicators are summarized in a series of tables: general indicators, supply indicators (reserves, refining and electric capacity, energy production, foreign trade), demand indicators (consumption trends, end use, energy independence, energy efficiency, CO 2 emissions), energy status per year and per energy source. (J.S.)

  5. Statistical downscaling of IPCC sea surface wind and wind energy predictions for U.S. east coastal ocean, Gulf of Mexico and Caribbean Sea

    Science.gov (United States)

    Yao, Zhigang; Xue, Zuo; He, Ruoying; Bao, Xianwen; Song, Jun

    2016-08-01

    A multivariate statistical downscaling method is developed to produce regional, high-resolution, coastal surface wind fields based on the IPCC global model predictions for the U.S. east coastal ocean, the Gulf of Mexico (GOM), and the Caribbean Sea. The statistical relationship is built upon linear regressions between the empirical orthogonal function (EOF) spaces of a cross- calibrated, multi-platform, multi-instrument ocean surface wind velocity dataset (predictand) and the global NCEP wind reanalysis (predictor) over a 10 year period from 2000 to 2009. The statistical relationship is validated before applications and its effectiveness is confirmed by the good agreement between downscaled wind fields based on the NCEP reanalysis and in-situ surface wind measured at 16 National Data Buoy Center (NDBC) buoys in the U.S. east coastal ocean and the GOM during 1992-1999. The predictand-predictor relationship is applied to IPCC GFDL model output (2.0°×2.5°) of downscaled coastal wind at 0.25°×0.25° resolution. The temporal and spatial variability of future predicted wind speeds and wind energy potential over the study region are further quantified. It is shown that wind speed and power would significantly be reduced in the high CO2 climate scenario offshore of the mid-Atlantic and northeast U.S., with the speed falling to one quarter of its original value.

  6. Hydrogeochemical characterization of the phreatic system of the coastal wetland located between Fiumi Uniti and Bevano rivers in the southern Po plain (Northern Italy).

    Science.gov (United States)

    Marconi, V.; Dinelli, E.; Antonellini, M.; Capaccioni, B.; Balugani, E.; Gabbianelli, G.

    2009-04-01

    A hydrogeochemical study has been undertaken on the phreatic system of the coastal area included between Fiumi Uniti and Bevano rivers (in the southern part of the Po plain, near the city of Ravenna) within the framework of the CIRCLE-ERANET project WATERKNOW on the effects of climate change on the mediterranean catchments. It is one of the first attempt in the area to characterize the shallow groundwater water system and to investigate if the arsenic anomaly, known in deeper groundwater (about 100 µg/l according to recent Annual Groundwater Quality Reports of Emilia-Romagna Region), occurs also in the phreatic system. 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 study area is recognized as a protected area at european (ZPS and SIC, site code number: IT 14070009), national and regional level (Po delta Park area). As a result of an intensive exploitation of coastal aquifers for agricultural, industrial, and civil uses, both the phreatic aquifer and the surface waters (drainage ditches and ponds) have been contaminated by seawater and by deeper groundwater. Samples representative of the top of the water table were collected in Summer 2008 in 22 auger-holes and in 3 shallow piezometers (6 m deep) documenting the deeper layers of the phreatic groundwater system. Temperature, electrical conductivity, pH and Eh of the groundwater and of the surface water were measured on site using portable instruments. Samples were filtered directly in the field, an aliquot was acidified with diluted HCl for metal analysis. Cations were determined by Flame Atomic Absorption (thermo S-series spectrometer), anions by ion chromatography (Dionex ICS-90), Fe, As, Si, B by ICP-OES (Thermo iCAP6000). The data collected in the field show that a fresh groundwater lens is still present at the top of the phreatic aquifer in the backshore area and that the

  7. The Gulf of Mexico research initiative: It takes a village

    Science.gov (United States)

    Colwell, Rita R.

    2016-07-01

    The Gulf of Mexico Research Initiative (GoMRI) was established at the time of one of the most significant ecological events in recent memory, the Deepwater Horizon oil spill. Defined by the discharge of over 150 million gallons of crude oil and the introduction of over 1.8 million gallons of chemical dispersants into the Gulf system, the impacts of the Deepwater Horizon disaster reached the Gulf Coast's wetlands and beaches and impacted the surface and deep ocean. The ecological story of the event reveals a strong linkage between the deep sea research community and research priorities in the Gulf of Mexico (coastal processes, human health, etc.). Deep Sea research efforts have revealed critical parts of the story, providing information on transport, fate, and effects of the Deepwater Horizon oil release and subsequent recovery of the Gulf of Mexico ecosystems.

  8. Development of an indicator to monitor mediterranean wetlands.

    Science.gov (United States)

    Sanchez, Antonio; Abdul Malak, Dania; Guelmami, Anis; Perennou, Christian

    2015-01-01

    Wetlands are sensitive ecosystems that are increasingly subjected to threats from anthropogenic factors. In the last decades, coastal Mediterranean wetlands have been suffering considerable pressures from land use change, intensification of urban growth, increasing tourism infrastructure and intensification of agricultural practices. Remote sensing (RS) and Geographic Information Systems (GIS) techniques are efficient tools that can support monitoring Mediterranean coastal wetlands on large scales and over long periods of time. The study aims at developing a wetland indicator to support monitoring Mediterranean coastal wetlands using these techniques. The indicator makes use of multi-temporal Landsat images, land use reference layers, a 50m numerical model of the territory (NMT) and Corine Land Cover (CLC) for the identification and mapping of wetlands. The approach combines supervised image classification techniques making use of vegetation indices and decision tree analysis to identify the surface covered by wetlands at a given date. A validation process is put in place to compare outcomes with existing local wetland inventories to check the results reliability. The indicator´s results demonstrate an improvement in the level of precision of change detection methods achieved by traditional tools providing reliability up to 95% in main wetland areas. The results confirm that the use of RS techniques improves the precision of wetland detection compared to the use of CLC for wetland monitoring and stress the strong relation between the level of wetland detection and the nature of the wetland areas and the monitoring scale considered.

  9. Summary Report on Information Technology Integration Activities For project to Enhance NASA Tools for Coastal Managers in the Gulf of Mexico and Support Technology Transfer to Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Gulbransen, Thomas C.

    2009-04-27

    Deliverable to NASA Stennis Space Center summarizing summarizes accomplishments made by Battelle and its subcontractors to integrate NASA's COAST visualization tool with the Noesis search tool developed under the Gulf of Mexico Regional Collaborative project.

  10. Ocean Carbon and Biogeochemistry Scoping Workshop on Terrestrial and Coastal Carbon Fluxes in the Gulf of Mexico, St. Petersburg, FL, May 6-8, 2008

    Science.gov (United States)

    Robbins, L.L.; Coble, P.G.; Clayton, T.D.; Cai, W.J.

    2009-01-01

    Despite their relatively small surface area, ocean margins may have a significant impact on global biogeochemical cycles and, potentially, the global air-sea fluxes of carbon dioxide. Margins are characterized by intense geochemical and biological processing of carbon and other elements and exchange large amounts of matter and energy with the open ocean. The area-specific rates of productivity, biogeochemical cycling, and organic/inorganic matter sequestration are high in coastal margins, with as much as half of the global integrated new production occurring over the continental shelves and slopes (Walsh, 1991; Doney and Hood, 2002; Jahnke, in press). However, the current lack of knowledge and understanding of biogeochemical processes occurring at the ocean margins has left them largely ignored in most of the previous global assessments of the oceanic carbon cycle (Doney and Hood, 2002). A major source of North American and global uncertainty is the Gulf of Mexico, a large semi-enclosed subtropical basin bordered by the United States, Mexico, and Cuba. Like many of the marginal oceans worldwide, the Gulf of Mexico remains largely unsampled and poorly characterized in terms of its air-sea exchange of carbon dioxide and other carbon fluxes. In May 2008, the Ocean Carbon and Biogeochemistry Scoping Workshop on Terrestrial and Coastal Carbon Fluxes in the Gulf of Mexico was held in St. Petersburg, FL, to address the information gaps of carbon fluxes associated with the Gulf of Mexico and to offer recommendations to guide future research. The meeting was attended by over 90 participants from over 50 U.S. and Mexican institutions and agencies. The Ocean Carbon and Biogeochemistry program (OCB; http://www.us-ocb.org/) sponsored this workshop with support from the National Science Foundation, the National Oceanic and Atmospheric Administration, the National Aeronautics and Space Administration, the U.S. Geological Survey, and the University of South Florida. The goal of

  11. Statistical Models for Sediment/Detritus and Dissolved Absorption Coefficients in Coastal Waters of the Northern Gulf of Mexico

    National Research Council Canada - National Science Library

    Green, Rebecca E; Gould, Jr., Richard W; Ko, Dong S

    2008-01-01

    ... (CDOM) absorption coefficients from physical hydrographic and atmospheric properties. The models were developed for northern Gulf of Mexico shelf waters using multi-year satellite and physical data...

  12. Comparative age and growth of common snook Centropomus undecimalis (Pisces: Centropomidae from coastal and riverine areas in Southern Mexico

    Directory of Open Access Journals (Sweden)

    Martha A. Perera-Garcia

    2013-06-01

    Full Text Available Common snook Centropomus unidecimalis is an important commercial and fishery species in Southern Mexico, however the high exploitation rates have resulted in a strong reduction of its abundances. Since, the information about its population structure is scarce, the objective of the present research was to determine and compare the age structure in four important fishery sites. For this, age and growth of common snook were determined from specimens collected monthly, from July 2006 to March 2008, from two coastal (Barra Bosque and Barra San Pedro and two riverine (San Pedro and Tres Brazos commercial fishery sites in Tabasco, Mexico. Age was determined using sectioned saggitae otoliths and data analyzed by von Bertalanffy and Levenberg-Marquardt among others. Estimated ages ranged from 2 to 17 years. Monthly patterns of marginal increment formation and the percentage of otoliths with opaque rings on the outer edge demonstrated that a single annulus was formed each year. The von Bertalanffy parameters were calculated for males and females using linear adjustment and the non-linear method of Levenberg-Marquardt. The von Bertalanffy growth equations were FLt=109.21(1-e-0.21(t+0.57 for Barra Bosque, FLt=94.56(1-e-0.27(t+0.48 for Barra San Pedro, FLt=97.15(1-e-0.17(t+1.32 for San Pedro and FLt=83.77(1-e-0.26(t+0.49 for Tres Brazos. According to (Hotelling’s T², pEl robalo blanco Centropomus undecimalis representa un ingreso monetario significativo y un recurso alimentario para todas las comunidades rurales cercanas a su distribución. Se determinó la edad y crecimiento de esta especie. Los organismos se recolectaron mensualmente en los desembarcos de la pesca artesanal de las cooperativas de mayor contribución en la zona costera (Barra Bosque y San Pedro y ribereña (San Pedro y Tres Brazos entre julio 2006 y marzo 2008. La edad se determinó mediante otolitos seccionados. La edad estimada fue de 2 a 17 años. Mensualmente se estableció la

  13. Biogenic origin of coalbed gas in the northern Gulf of Mexico Coastal Plain, U.S.A

    Science.gov (United States)

    Warwick, Peter D.; Breland, F. Clayton; Hackley, Paul C.

    2008-01-01

    New coal-gas exploration and production in northern Louisiana and south-central Mississippi, Gulf of Mexico Basin, is focused on the Wilcox Group (Paleocene–Eocene), where the depth to targeted subbituminous C to high volatile C bituminous coal beds ranges from 300 to 1680 m, and individual coal beds have a maximum thickness of about 6 m. Total gas content (generally excluding residual gas) of the coal beds ranges from less than 0.37 cm3/g (as-analyzed or raw basis; 1.2 cm3/g, dry, ash free basis, daf) at depths less than 400 m, to greater than 7.3 cm3/g (as-analyzed basis; 8.76 cm3/g, daf) in deeper (> 1,500 m) parts of the basin. About 20 Wilcox coal-gas wells in northern Louisiana produce from 200 to 6485 m3 of gas/day and cumulative gas production from these wells is approximately 25 million m3 (as of December, 2006). U.S. Geological Survey assessment of undiscovered, technically recoverable gas resources in the Gulf of Mexico Coastal Plain, including northern and south-central Mississippi, indicates that coal beds of the Wilcox Group contain an estimated mean total 109.3 million m3 (3.86 trillion ft3) of producible natural gas.To determine the origin of the Wilcox Group coal gases in northern Louisiana, samples of gas, water, and oil were collected from Wilcox coal and sandstone reservoirs and from under- and overlying Late Cretaceous and Eocene carbonate and sandstone reservoirs. Isotopic data from Wilcox coal-gas samples have an average δ13CCH4 value of − 62.6‰ VPDB (relative to Vienna Peedee Belemnite) and an average δDCH4 value of − 199.9‰ VSMOW (relative to Vienna Standard Mean Ocean Water). Values of δ13CCO2 range from − 25.4 to 3.42‰ VPDB. Produced Wilcox saline water collected from oil, conventional gas, and coalbed gas wells have δDH2O values that range from − 27.3 to − 18.0‰ VSMOW. These data suggest that the coal gases primarily are generated in saline formation water by bacterial reduction of CO2

  14. Biogenic origin of coalbed gas in the northern Gulf of Mexico Coastal Plain, U.S.A.

    Energy Technology Data Exchange (ETDEWEB)

    Warwick, Peter D.; Hackley, Paul C. [U.S. Geological Survey, 956 National Center, Reston, VA 20192 (United States); Breland, F. Clayton Jr. [Louisiana Department of Natural Resources, 617 North 3rd Street, Baton Rouge, LA 70802 (United States)

    2008-10-02

    New coal-gas exploration and production in northern Louisiana and south-central Mississippi, Gulf of Mexico Basin, is focused on the Wilcox Group (Paleocene-Eocene), where the depth to targeted subbituminous C to high volatile C bituminous coal beds ranges from 300 to 1680 m, and individual coal beds have a maximum thickness of about 6 m. Total gas content (generally excluding residual gas) of the coal beds ranges from less than 0.37 cm{sup 3}/g (as-analyzed or raw basis; 1.2 cm{sup 3}/g, dry, ash free basis, daf) at depths less than 400 m, to greater than 7.3 cm{sup 3}/g (as-analyzed basis; 8.76 cm{sup 3}/g, daf) in deeper (> 1,500 m) parts of the basin. About 20 Wilcox coal-gas wells in northern Louisiana produce from 200 to 6485 m{sup 3} of gas/day and cumulative gas production from these wells is approximately 25 million m{sup 3} (as of December, 2006). U.S. Geological Survey assessment of undiscovered, technically recoverable gas resources in the Gulf of Mexico Coastal Plain, including northern and south-central Mississippi, indicates that coal beds of the Wilcox Group contain an estimated mean total 109.3 million m{sup 3} (3.86 trillion ft{sup 3}) of producible natural gas. To determine the origin of the Wilcox Group coal gases in northern Louisiana, samples of gas, water, and oil were collected from Wilcox coal and sandstone reservoirs and from under- and overlying Late Cretaceous and Eocene carbonate and sandstone reservoirs. Isotopic data from Wilcox coal-gas samples have an average {delta}{sup 13}C{sub CH4} value of - 62.6 permille VPDB (relative to Vienna Peedee Belemnite) and an average {delta}D{sub CH4} value of - 199.9 permille VSMOW (relative to Vienna Standard Mean Ocean Water). Values of {delta}{sup 13}C{sub CO2} range from - 25.4 to 3.42 permille VPDB. Produced Wilcox saline water collected from oil, conventional gas, and coalbed gas wells have {delta}D{sub H2O} values that range from - 27.3 to - 18.0 permille VSMOW. These data suggest that the

  15. 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

  16. Conservation of Mexican wetlands: role of the North American Wetlands Conservation Act

    Science.gov (United States)

    Wilson, M.H.; Ryan, D.A.

    1997-01-01

    Mexico's wetlands support a tremendous biological diversity and provide significant natural resource benefits to local communities. Because they are also critical stopover and wintering grounds for much of North America's waterfowl and other migratory birds, Mexico has become an important participant in continental efforts to conserve these resources through the North American Wetlands Conservation Act. Funding from the Act has supported partnerships in a number of Mexico's priority wetlands to conduct data analyses and dissemination, mapping, environmental education, wetland restoration, development of sustainable economic alternatives for local people, and reserve planning and management. These partnerships, with the close involvement of Mexico's Federal Government authority, the Instituto Nacional de Ecologia, have advanced conservation in a uniquely Mexican model that differs from that employed in the United States and Canada.

  17. Advanced data processing of airborne electromagnetic data for imaging hidden conduit networks in the coastal karst plain of Tulum (Mexico); Tecnicas avanzadas de analisis de datos electromagneticos aerotransportados para cartografia de redes de conductos karsticos de la planicie costera de Tulum (Mexico)

    Energy Technology Data Exchange (ETDEWEB)

    Schiller, A.; Schattauer, I.; Ottowitz, D.

    2016-07-01

    This study is part of a series of international research cooperations which commenced in 2007 and are still ongoing. The study area is located on the east coast of the Yucatan Peninsula, Mexico, and comprises the northern most part of the Sian Kaan biosphere reserve, a coastal wetland of international importance, as well as the city of Tulum in the state of Quintana Roo, and part of the second largest barrier reef in the world some 300 metres to one kilometre off shore. Two airborne surveys, conducted in 2007 and 2008 by the Geological Survey of Austria, covered an area of some 200 square kilometres, including the well-known Ox Bel Ha cave system, already mapped by exploration divers. In order to get additional ground truth data and input for the hydrological model, extended ground geophysical campaigns have been conducted an - nually. The first processing of the airborne electromagnetic (AEM) data revealed not only a clear signature from known caves but also the image of a vast, unexplored, hidden conduit network. However, lateral and depth resolution was limited due to measurement drift and noise as well the specific behaviour of the ap - plied inversion technique. Newly developed algorithms for processing AEM data and inversion results have improved the signal-to-noise ratio significantly and enabled the imaging of well defined structures in the underground. Therefore, the AEM method is now capable of quickly deliver crucial structural information of karst-water regimes in difficult accessible areas with unique depth information compared to previous studies. (Author)

  18. Evaluation of the health status of a coastal ecosystem in southeast Mexico: Assessment of water quality, phytoplankton and submerged aquatic vegetation.

    Science.gov (United States)

    Herrera-Silveira, Jorge A; Morales-Ojeda, Sara M

    2009-01-01

    The coastal environment of the Yucatan Peninsula (SE, Mexico) includes a wide variety of ecosystems ranging from mangroves to coral reefs, resulting in a heterogeneous landscape. Specifically, the marine system is characterized by environmental differences which respond to regional and local forcing functions such as marine currents and groundwater discharges (GD). Such functional characteristics were used here to define four subregions across the Yucatan coast and diagnose the health status of this coastal marine ecosystem. To achieve this goal, we conducted an analysis and integration of water quality variables, an eutrophic assessment, evaluated changes in submerged aquatic vegetation (SAV), and analyzed the community structure and distribution of harmful phytoplankton. The first step was to determine the reference values for each subregion based on data previously collected from 2002 to 2006 along the coast of Yucatan, 200m offshore. The trophic index (TRIX) and Canadian index for aquatic life (CCMEWQI) were used to diagnose each subregion and then the ASSETS approach was conducted for Dzilam and Progreso, sampling localities on each end of the health status continuum (those with the best and worst conditions). Overall, results indicated that the marine coastal ecosystem of Yucatan is in good condition; however, differences were observed between subregions that can be attributed to local forcing functions and human impacts. Specifically, the central region (zone HZII, Progreso-Telchac) showed symptoms of initial eutrophication due to nutrient inputs from human activities. The eastern region (zone HZ III, Dzilam-Las Bocas) showed a meso-eutrophic condition linked to natural groundwater discharges, while the other two subregions western (zone HZI Celestun-Palmar) and caribbean (zone HZ IV Ria Lagartos-El Cuyo) exhibited symptoms of oligo-mesotrophic condition. These findings may be considered baseline information for coastal ecosystem monitoring programs in

  19. Ecosystem level methane fluxes from tidal freshwater and brackish marshes of the Mississippi River Delta: Implications for coastal wetland carbon projects

    Science.gov (United States)

    Holm, Guerry O.; Perez, Brian C.; McWhorter, David E.; Krauss, Ken W.; Johnson, Darren J.; Raynie, Richard C.; Killebrew, Charles J.

    2016-01-01

    Sulfate from seawater inhibits methane production in tidal wetlands, and by extension, salinity has been used as a general predictor of methane emissions. With the need to reduce methane flux uncertainties from tidal wetlands, eddy covariance (EC) techniques provide an integrated methane budget. The goals of this study were to: 1) establish methane emissions from natural, freshwater and brackish wetlands in Louisiana based on EC; and 2) determine if EC estimates conform to a methane-salinity relationship derived from temperate tidal wetlands with chamber sampling. Annual estimates of methane emissions from this study were 62.3 g CH4/m2/yr and 13.8 g CH4/m2/yr for the freshwater and brackish (8–10 psu) sites, respectively. If it is assumed that long-term, annual soil carbon sequestration rates of natural marshes are ~200 g C/m2/yr (7.3 tCO2e/ha/yr), healthy brackish marshes could be expected to act as a net radiative sink, equivalent to less than one-half the soil carbon accumulation rate after subtracting methane emissions (4.1 tCO2e/ha/yr). Carbon sequestration rates would need case-by-case assessment, but the EC methane emissions estimates in this study conformed well to an existing salinity-methane model that should serve as a basis for establishing emission factors for wetland carbon offset projects.

  20. Comparative analysis of bacterial community-metagenomics in coastal Gulf of Mexico sediment microcosms following exposure to Macondo oil (MC252)

    KAUST Repository

    Koo, Hyunmin

    2014-09-10

    The indigenous bacterial communities in sediment microcosms from Dauphin Island (DI), Petit Bois Island (PB) and Perdido Pass (PP) of the coastal Gulf of Mexico were compared following treatment with Macondo oil (MC252) using pyrosequencing and culture-based approaches. After quality-based trimming, 28,991 partial 16S rRNA sequence reads were analyzed by rarefaction, confirming that analyses of bacterial communities were saturated with respect to species diversity. Changes in the relative abundances of Proteobacteria, Bacteroidetes and Firmicutes played an important role in structuring bacterial communities in oil-treated sediments. Proteobacteria were dominant in oil-treated samples, whereas Firmicutes and Bacteroidetes were either the second or the third most abundant taxa. Tenericutes, members of which are known for oil biodegradation, were detected shortly after treatment, and continued to increase in DI and PP sediments. Multivariate statistical analyses (ADONIS) revealed significant dissimilarity of bacterial communities between oil-treated and untreated samples and among locations. In addition, a similarity percentage analysis showed the contribution of each species to the contrast between untreated and oil-treated samples. PCR amplification using DNA from pure cultures of Exiguobacterium,  Pseudoalteromonas,  Halomonas and Dyadobacter, isolated from oil-treated microcosm sediments, produced amplicons similar to polycyclic aromatic hydrocarbon-degrading genes. In the context of the 2010 Macondo blowout, the results from our study demonstrated that the indigenous bacterial communities in coastal Gulf of Mexico sediment microcosms responded to the MC252 oil with altered community structure and species composition. The rapid proliferation of hydrocarbonoclastic bacteria suggests their involvement in the degradation of the spilt oil in the Gulf of Mexico ecosystem.

  1. Spatio-temporal variability of internal waves in the northern Gulf of Mexico studied with the Navy Coastal Ocean Model, NCOM

    Science.gov (United States)

    Cambazoglu, M. K.; Jacobs, G. A.; Howden, S. D.; Book, J. W.; Arnone, R.; Soto Ramos, I. M.; Vandermeulen, R. A.; Greer, A. T.; Miles, T. N.

    2016-02-01

    Internal waves enhance mixing in the upper ocean, transport nutrients and plankton over the water column and across the shelf from deeper waters to shallower coastal areas, and could also transport pollutants such as hydrocarbons onshore during an oil spill event. This study aims to characterize internal waves in the northern Gulf of Mexico (nGoM) and investigate the possible generation and dissipation mechanisms using a high-resolution (1-km) application of the Navy Coastal Ocean Model (NCOM). Three dimensional model products are used to detect the propagation patterns of internal waves. The vertical structure of internal waves is studied and the role of stratification is analyzed by looking at the temperature, salinity and velocity variations along the water column. The model predictions suggest the generation of internal waves on the continental shelf, therefore the role of ocean bottom topography interacting with tides and general circulation features such as the Loop Current Eddy front, on the internal wave generation will be discussed. The time periods of internal wave occurrences are identified from model predictions and compared to satellite ocean color imagery. Further data analysis, e.g. Fourier analysis, is implemented to determine internal wavelengths and frequencies and to determine if the response of internal waves are at tidal periods or at different frequencies. The atmospheric forcing provided to NCOM and meteorological data records are analyzed to define the interaction between wind forcing and internal wave generation. Wavelet analysis characterizes the ocean response to atmospheric events with periodic frequencies. Ocean color satellite imagery was used to visualize the location of the Mississippi river plume (and other oceanic features) and compared to the model predictions because the enhanced stratification from freshwater plumes which propagate across the Mississippi Bight can provide favorable conditions in coastal waters for internal wave

  2. Interaction between continental and estuarine waters in the wetlands of the northern coastal plain of Samborombón Bay, Argentina

    International Nuclear Information System (INIS)

    Carol, Eleonora; Mas-Pla, Josep; Kruse, Eduardo

    2013-01-01

    Highlights: • Inland and estuarine water flows define wetland hydrology on the Samborombón Bay. • Hydrochemistry in shell-ridges and tidal plains is due to water–rock interaction. • Mixing, evaporation and halite dissolution determine salinity in marshes. • Water flow from the shell-ridges control the overall wetland water quality. • These wetlands are complex hydrological systems with vulnerable water resources. - Abstract: On the Samborombón Bay coastline, located in the Río de la Plata estuary in Buenos Aires province (Argentina), a complex hydrological system has developed at the interface between continental and estuarine water, where significant wetlands develop. The main hydrogeological units, namely the shell ridges, the tidal plain and the marsh areas, have been identified using geomorphological criteria. Water table, hydrochemical and isotopic data have been used to determine their hydrological features, as well as those of the streams and canals. Evaporation processes, in particular, have been considered when depicting chemical and isotopic changes in surface waters in streams and marsh areas. The shell ridges represent a hydrogeological unit in which rainwater is stored, constituting a lens-shaped freshwater aquifer. In this unit, just as in the tidal plain, carbonate dissolution and ion exchange are the main processes regulating water chemistry. On the other hand, in the marsh and surface waters, processes such as mixing with estuarine water and evaporation predominate. These processes control water fluxes and the salinity of the wetland areas and, consequently, their ability to preserve the existing biodiversity. This study shows the importance of knowledge of hydrochemical processes in any proposal concerning the management and preservation of this type of wetland

  3. Hurricanes Katrina and Rita and the Coastal Louisiana Ecosystem Restoration

    National Research Council Canada - National Science Library

    Zinn, Jeffrey

    2005-01-01

    ... for a $1.1 billion multiyear program to construct five projects that would help to restore portions of the coastal Louisiana ecosystem by slowing the rate of wetland loss and restoring some wetlands...

  4. Modeling the local biodiversity impacts of agricultural water use: case study of a wetland in the coastal arid area of Peru.

    Science.gov (United States)

    Verones, Francesca; Bartl, Karin; Pfister, Stephan; Jiménez Vílchez, Ricardo; Hellweg, Stefanie

    2012-05-01

    Global water use is dominated by agriculture and has considerable influence on people's livelihood and ecosystems, especially in semiarid and arid regions. Methods to address the impacts of water withdrawal and consumption on terrestrial and aquatic ecosystems within life cycle assessment are still sparse and very generic. Regionalized characterization factors (CFs) for a groundwater-fed wetland at the arid coast of Peru are developed for groundwater and surface water withdrawal and consumption in order to address the spatial dependency of water use related impacts. Several agricultural scenarios for 2020 were developed in a workshop with local stakeholders and used for calculating total biodiversity impacts. In contrast to assumptions used in top-down approaches (e.g., Pfister et al. Environ. Sci Technol. 2009, 43, 4098 ), irrigation with surface water leads in this specific region to benefits for the groundwater-fed wetland, due to additional groundwater recharge from surplus irrigation water. However, irrigation with groundwater leads to ecological damage to the wetland. The CFs derived from the different scenarios are similar and can thus be used as general CFs for this region, helping local decision-makers to plan future agricultural development, including irrigation technologies, crop choices, and protection of the wetland. © 2012 American Chemical Society

  5. Satellite Assessment of Bio-Optical Properties of Northern Gulf of Mexico Coastal Waters Following Hurricanes Katrina and Rita

    OpenAIRE

    Lohrenz, Steven E.; Cai, Wei-Jun; Chen, Xiaogang; Tuel, Merritt

    2008-01-01

    The impacts of major tropical storms events on coastal waters include sediment resuspension, intense water column mixing, and increased delivery of terrestrial materials into coastal waters. We examined satellite imagery acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) ocean color sensor aboard the Aqua spacecraft following two major hurricane events: Hurricane Katrina, which made landfall on 29 August 2005, and Hurricane Rita, which made landfall on 24 September. MODIS A...

  6. Wetland Hydrology

    Science.gov (United States)

    This chapter discusses the state of the science in wetland hydrology by touching upon the major hydraulic and hydrologic processes in these complex ecosystems, their measurement/estimation techniques, and modeling methods. It starts with the definition of wetlands, their benefit...

  7. The concentrations of five heavy metals in components of an economically important urban coastal wetland in Ghana: public health and phytoremediation implications.

    Science.gov (United States)

    Gbogbo, Francis; Otoo, Samuel D

    2015-10-01

    Sakumo II is an urban wetland and a receptacle for domestic and industrial wastes from two cities in Ghana. It however supports viable populations of fish and crabs, is cultivated for food crops and grazed by farm animals. Components of the wetland can therefore accumulate pollutants, but the public health and phytoremediation implications of this are yet to be evaluated. We analysed Cd, As, Hg, Cu and Pb in the lagoon water, sediment, green algae, eight species of aquatic macrophytes, seven species of arthropods and one species of fish. The concentrations of Pb were generally below detection limit whilst Cu was detected only in the lagoon water and Pheropsophus vertialis. Cadmium ranged from 21 ± 4 ppb in algae to 69 ± 12 ppb in Typha domingensis and was generally higher than As and Hg. The highest concentration of As was 11.7 ± 2.1 ppb in Pistia stratiotes whilst Hg was highest in lagoon water (4 ± 2 ppb). The Cd concentrations generally, and Hg concentrations in macrophytes, were higher than US EPA guidelines indicating the wetland's resources were unsafe for regular consumption. Among the emergent aquatic macrophytes, T. domingensis, Ludwigia sp. and Paspalum vaginatum, respectively, had the highest accumulation capacity for Cd, As and Hg, but the floating aquatic plant P. stratiotes appeared to be a better accumulator of Cd and As.

  8. 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

  9. Environmental and economic assessment of discharges from Gulf of Mexico Region Oil and Gas Operations

    International Nuclear Information System (INIS)

    Gettleson, D.A.

    1997-01-01

    Task 3 (Environmental Field Sampling and Analysis of NORM, Heavy Metals, and Organics) and 4 (Monitoring of the Recovery of Impacted Wetland and Open Bay Produced Water Discharge Sites in Coastal Louisiana and Texas) activities involved continued data analysis and report writing. Task 5 (Assessment of Economic Impacts of Offshore and Coastal Discharge Requirements on Present and Future Operations in the Gulf of Mexico Region) was issued as a final report during the previous reporting period. Task 6 (Synthesis of Gulf of Mexico Seafood Consumption and Use Patterns) activities included the preparation of the final report. There were no Task 7 (Technology Transfer Plan) activities to report. Task 8 (Project Management and Deliverables) activities involved the submission of the necessary reports and routine management

  10. National Wetlands Inventory Lines

    Data.gov (United States)

    Minnesota Department of Natural Resources — Linear wetland features (including selected streams, ditches, and narrow wetland bodies) mapped as part of the National Wetlands Inventory (NWI). The National...

  11. Phylogenetic relationships of leopard frogs (Rana pipiens complex) from an isolated coastal mountain range in southern Sonora, Mexico.

    Science.gov (United States)

    Pfeiler, E; Markow, T A

    2008-10-01

    Mitochondrial DNA sequence data from the control region and 12S rRNA in leopard frogs from the Sierra El Aguaje of southern Sonora, Mexico, together with GenBank sequences, were used to infer taxonomic identity and provide phylogenetic hypotheses for relationships with other members of the Rana pipiens complex. We show that frogs from the Sierra El Aguaje belong to the Rana berlandieri subgroup, or Scurrilirana clade, of the R. pipiens group, and are most closely related to Rana magnaocularis from Nayarit, Mexico. We also provide further evidence that Rana magnaocularis and R. yavapaiensis are close relatives.

  12. Three decadal inputs of total organic carbon from four major coastal river basins to the summer hypoxic zone of the Northern Gulf of Mexico.

    Science.gov (United States)

    He, Songjie; Xu, Y Jun

    2015-01-15

    This study investigated long-term (1980-2009) yields and variability of total organic carbon (TOC) from four major coastal rivers in Louisiana entering the Northern Gulf of Mexico where a large-area summer hypoxic zone has been occurring since the middle 1980s. Two of these rivers drain agriculture-intensive (>40%) watersheds, while the other two rivers drain forest-pasture dominated (>50%) watersheds. The study found that these rivers discharged a total of 13.0×10(4)t TOC annually, fluctuating from 5.9×10(4) to 22.8×10(4)t. Seasonally, the rivers showed high TOC yield during the winter and early spring months, corresponding to the seasonal trend of river discharge. While river hydrology controlled TOC yields, land use has played an important role in fluxes, seasonal variations, and characteristics of TOC. The findings fill in a critical information gap of quantity and quality of organic carbon transport from coastal watersheds to one of the world's largest summer hypoxic zones. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Environmental and economic assessment of discharges from Gulf of Mexico Region oil and gas operation. Quarterly technical progress report, 1 October--31 December 1994

    International Nuclear Information System (INIS)

    Gettleson, D.A.

    1995-01-01

    Task 3 (Environmental Field Sampling and Analysis of NORM, Heavy Metals, and Organics) work included analyses of samples. Task 4 (Monitoring of the Recovery of Impacted Wetland and Open Bay Produced Water Discharge Sites in Coastal Louisiana and Texas) activities involved the continued analyses of samples and field sampling at Bay de Chene. Task 5 (Assessment of Economic Impacts of Offshore and Coastal Discharge Requirements on Present and Future Operations in the Gulf of Mexico Region) activities included preparing a draft final report. Task 6 (Synthesis of Gulf of Mexico Seafood Consumption and Use Patterns) work also involved preparing a draft final report. Task 7 (Technology Transfer Plan) activities included a presentation at the Minerals Management Service Information Transfer Meeting for the Gulf of Mexico OCS Region. Task 8 (Project Management and Deliverables) activities involved the submission of the necessary reports and routine management

  14. Extreme storms, sea level rise, and coastal change: implications for infrastructure reliability in the Gulf of Mexico

    Science.gov (United States)

    Anarde, K.; Kameshwar, S.; Irza, N.; Lorenzo-Trueba, J.; Nittrouer, J. A.; Padgett, J.; Bedient, P. B.

    2016-12-01

    Predicting coastal infrastructure reliability during hurricane events is important for risk-based design and disaster planning, such as delineating viable emergency response routes. Previous research has focused on either infrastructure vulnerability to coastal flooding or the impact of changing sea level and landforms on surge dynamics. Here we investigate the combined impact of sea level, morphology, and coastal flooding on the reliability of highway bridges - the only access points between barrier islands and mainland communities - during future extreme storms. We forward model coastal flooding for static projections of geomorphic change using ADCIRC+SWAN. First-order parameters that are adjusted include sea level and elevation. These are varied for each storm simulation to evaluate relative impact on the reliability of bridges surrounding Freeport, TX. Simulated storms include both synthetic and historical events, which are classified by intensity using the storm's integrated kinetic energy, a metric for surge generation potential. Reliability is estimated through probability of failure - given wave and surge loads - and time inundated. Findings include that: 1) bridge reliability scales inversely with surge height, and 2) sea level rise reduces bridge reliability due to a monotonic increase in surge height. The impact of a shifting landscape on bridge reliability is more complex: barrier island rollback can increase or decrease inundation times for storms of different intensity due to changes in wind-setup and back-barrier bay interactions. Initial storm surge readily inundates the coastal landscape during large intensity storms, however the draining of inland bays following storm passage is significantly impeded by the barrier. From a coastal engineering standpoint, we determine that to protect critical infrastructure, efforts now implemented that nourish low-lying barriers may be enhanced by also armoring back-bay coastlines and elevating bridge approach

  15. 77 FR 50388 - Coastal Migratory Pelagic Resources of the Gulf of Mexico and South Atlantic; 2012-2013...

    Science.gov (United States)

    2012-08-21

    ... Brownsville, Texas) and continues to the boundary between the eastern and western zones at 87[deg]31.1[min] W... Atlantic; 2012-2013 Accountability Measure and Closure for Gulf King Mackerel in Western Zone AGENCY... king mackerel in the western zone of the Gulf of Mexico (Gulf) exclusive economic zone (EEZ) through...

  16. 78 FR 58248 - Coastal Migratory Pelagic Resources of the Gulf of Mexico and South Atlantic; 2013-2014...

    Science.gov (United States)

    2013-09-23

    ... between the eastern and western zones at 87[deg]31.1' W. long., which is a line directly south from the... Atlantic; 2013-2014 Accountability Measure and Closure for Gulf King Mackerel in Western Zone AGENCY... king mackerel in the western zone of the Gulf of Mexico (Gulf) exclusive economic zone (EEZ) through...

  17. 78 FR 64888 - Coastal Migratory Pelagic Resources of the Gulf of Mexico and South Atlantic; Reopening of the...

    Science.gov (United States)

    2013-10-30

    ... the boundary between the eastern and western zones at 87[deg]31.1' W. long., which is a line directly... Atlantic; Reopening of the Commercial Harvest of Gulf King Mackerel in Western Zone AGENCY: National Marine... western zone of the Gulf of Mexico (Gulf) exclusive economic zone (EEZ). NMFS previously projected that...

  18. 76 FR 5326 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; King and Spanish Mackerel Coastal...

    Science.gov (United States)

    2011-01-31

    ... Spanish Mackerel Coastal Migratory Pelagic Fishery Off the Southern Atlantic States; Control Date AGENCY... that it is establishing a new control date to control future access to the king and Spanish mackerel... September 17, 2010, for king and Spanish mackerel. The Council requested a new control date for the king and...

  19. Coastal Massachusetts Submerged Aquatic Beds 1994-1996 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Coastal Change Analysis Program (C-CAP) at NOAA Office for Coastal Management partnered with The Massachusetts Department of Environmental Protection Wetlands...

  20. Coastal Massachusetts Submerged Aquatic Beds 1994-1996 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Coastal Change Analysis Program (C-CAP) at NOAA Office for Coastal Management partnered with The Massachusetts Department of Environmental Protection Wetlands...

  1. Coastal Massachusetts Submerged Aquatic Beds 1994-1996 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Coastal Change Analysis Program (C-CAP) at NOAA Office for Coastal Management partnered with The Massachusetts Department of Environmental Protection Wetlands...

  2. Coastal Massachusetts Submerged Aquatic Beds 1994-1996 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Coastal Change Analysis Program (C-CAP) at NOAA Office for Coastal Management partnered with The Massachusetts Department of Environmental Protection Wetlands...

  3. Review of the Distribution of Waterbirds in Two Tropical coastal

    African Journals Online (AJOL)

    Administrator

    Areview of waterbirds was undertaken in two coastal Ramsar lagoons, namely the Keta and Muni Ramsar ... waterbirds, the East Atlantic Flyway and the ... In fact, Ghana‟s coastal wetlands are ...... such as mangrove forests, which serve as.

  4. National Assessment of Shoreline Change: Part 1, Historical Shoreline Changes and Associated Coastal Land Loss Along the U.S. Gulf of Mexico

    Science.gov (United States)

    Morton, Robert A.; Miller, Tara L.; Moore, Laura J.

    2004-01-01

    EXECUTIVE SUMMARY Beach erosion is a chronic problem along most open-ocean shores of the United States. As coastal populations continue to grow and community infrastructures are threatened by erosion, there is increased demand for accurate information regarding past and present trends and rates of shoreline movement. There is also a need for a comprehensive analysis of shoreline movement that is consistent from one coastal region to another. To meet these national needs, the U.S. Geological Survey is conducting an analysis of historical shoreline changes along open-ocean sandy shores of the conterminous United States and parts of Hawaii and Alaska. One purpose of this work is to develop standard repeatable methods for mapping and analyzing shoreline movement so that periodic updates regarding coastal erosion and land loss can be made nationally that are systematic and internally consistent. This report on states bordering the Gulf of Mexico (Florida, Alabama, Mississippi, Louisiana, and Texas) represents the first in a series that will eventually include the Atlantic Coast, Pacific Coast, and parts of Hawaii and Alaska. The report summarizes the methods of analysis, interprets the results, provides explanations regarding the historical and present trends and rates of change, and describes how different coastal communities are responding to coastal erosion. Shoreline change evaluations are based on comparing three historical shorelines with a recent shoreline derived from lidar (Light Detection and Ranging) topographic surveys. The historical shorelines generally represent the following periods: 1800s, 1920s-1930s, and 1970s, whereas the lidar shoreline is 1998-2002. Long-term rates of change are calculated using all four shorelines (1800s to lidar shoreline), whereas short-term rates of change are calculated for the most recent period (1970s to lidar shoreline). The historical rates of change presented in this report represent past conditions and therefore are not

  5. Planning report for the Gulf Coast Regional Aquifer-System Analysis in the Gulf of Mexico coastal plain, United States

    Science.gov (United States)

    Grubb, Hayes F.

    1984-01-01

    Large quantities of water for municipal, industrial and agriculture use are supplied from the aquifers in Tertiary and younger sediments over an area of about 225,000 square miles in the Coastal Plain of Alabama, Arkansas, Florida, Illinois, Kentucky, Louisiana, Mississippi, Missouri, Tennessee, and Texas. Three regional aquifer systems, the Mississippi Embayment aquifer system, the Coastal Lowlands aquifer system, and the Texas Coastal Uplands aquifer system have been developed to varying degrees throughout the area. A variety of problems has resulted from development such as movement of the saline-freshwater interface into parts of aquifers that were previously fresh, lowering of the potentiometric surface with resulting increases in pumping lift, and land-surface subsidence due to the compaction of clays within the aquifer. Increased demand for ground water is anticipated to meet the needs of urban growth, expanded energy development, and growth of irrigated agriculture. The U. S. Geological Survey initiated an eightyear study in 1981 to define the geohydrologic framework, describe the chemistry of the ground water, and to analyze the regional ground-water flow patterns. The objectives, plan, and organization of the study are described in this report and the major tasks to be undertaken are outlined.

  6. A Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing Wetland Functions of Depression Wetlands in the Upper Des Plaines River Basin

    Science.gov (United States)

    2006-05-01

    Wetlands and Coastal Ecology Branch; Dr. David J. Tazik, Chief, Eco- system Evaluation and Engineering Division; and Dr. Edwin A. Theriot, Direc- tor, EL...wetlands (Euliss and Mushet 1996, Azous and Horner 2001, Bhaduri et al. 1997) and nutrient loading into those wetlands. The overall LU score is...Euliss, N. H., and Mushet , D. M. (1996). “Water-level fluctuation in wetlands as a function of landscape condition in the prairie pothole region

  7. Modeling the Hydrologic Processes of a Depressional Forested Wetland in South Carolina, U.S.A.

    Science.gov (United States)

    Ge Sun; Timothy Callahan; Jennifer E. Pyzoha; Carl C. Trettin; Devendra M. Amatya

    2004-01-01

    Depressional forested wetlands or geographically isolated wetlands such as cypress swamps and Carolina bays are common land features in the Atlantic Coastal Plain of the southeastern US. Those wetlands play important roles in providing wildlife habitats, water quality improvement, and carbon sequestration. Great stresses have been imposed on those important ecosystems...

  8. Forested Wetlands: Functions, Benefits and the Use of Best Management Practices

    Science.gov (United States)

    David J. Welsch; David L. Smart; James N. Boyer; Paul Minken; Howard C. Smith; Tamara L. McCandless

    1995-01-01

    Wetlands are complex and fascinating ecosystems that perform a variety of functions of vital importance to the environment and to the society whose very existence depends on the quality of the environment. Wetlands regulate water flow by detaining storm flows for short periods thus reducing Wetlands protect lake shore and coastal areas by buffering the erosive action...

  9. Application of the Coastal and Marine Ecological Classification Standard to ROV Video Data for Enhanced Analysis of Deep-Sea Habitats in the Gulf of Mexico

    Science.gov (United States)

    Ruby, C.; Skarke, A. D.; Mesick, S.

    2016-02-01

    The Coastal and Marine Ecological Classification Standard (CMECS) is a network of common nomenclature that provides a comprehensive framework for organizing physical, biological, and chemical information about marine ecosystems. It was developed by the National Oceanic and Atmospheric Administration (NOAA) Coastal Services Center, in collaboration with other feral agencies and academic institutions, as a means for scientists to more easily access, compare, and integrate marine environmental data from a wide range of sources and time frames. CMECS has been endorsed by the Federal Geographic Data Committee (FGDC) as a national metadata standard. The research presented here is focused on the application of CMECS to deep-sea video and environmental data collected by the NOAA ROV Deep Discoverer and the NOAA Ship Okeanos Explorer in the Gulf of Mexico in 2011-2014. Specifically, a spatiotemporal index of the physical, chemical, biological, and geological features observed in ROV video records was developed in order to allow scientist, otherwise unfamiliar with the specific content of existing video data, to rapidly determine the abundance and distribution of features of interest, and thus evaluate the applicability of those video data to their research. CMECS units (setting, component, or modifier) for seafloor images extracted from high-definition ROV video data were established based upon visual assessment as well as analysis of coincident environmental sensor (temperature, conductivity), navigation (ROV position, depth, attitude), and log (narrative dive summary) data. The resulting classification units were integrated into easily searchable textual and geo-databases as well as an interactive web map. The spatial distribution and associations of deep-sea habitats as indicated by CMECS classifications are described and optimized methodological approaches for application of CMECS to deep-sea video and environmental data are presented.

  10. The effects of crude oil and the effectiveness of cleaner application following oiling on US Gulf of Mexico coastal marsh plants.

    Science.gov (United States)

    Pezeshki, S R; DeLaune, R D; Jugsujinda, A

    2001-01-01

    Field studies were conducted in two different marsh habitats in Louisiana coastal wetlands to evaluate the effects of oiling (using South Louisiana Crude oil, SLC) and the effectiveness of a shoreline cleaner (COREXIT 9580) in removing oil from plant canopies. The study sites represented two major marsh habitats; the brackish marsh site was covered by Spartina patens and the freshwater marsh was covered by Sagittaria lancifolia. Field studies were conducted in each habitat using replicated 5.8 m2 plots that were subjected to three treatments; oiled only, oiled + cleaner (cleaner was used 2 days after oiling), and a control. Plant gas exchange responses, survival, growth, and biomass accumulation were measured. Results indicated that oiling led to rapid reductions in leaf gas exchange rates in both species. However, both species in 'oiled + cleaned' plots displayed improved leaf conductance and CO2 fixation rates. Twelve weeks after treatment initiation, photosynthetic carbon fixation in both species had recovered to normal levels. Over the short-term, S. patens showed more sensitivity to oiling with SLC than S. lancifolia as was evident from the data of the number of live shoots and above-ground biomass. Above-ground biomass remained significantly lower than control in S. patens under 'oiled' and 'oiled + cleaned' treatments while it was comparable to controls in S. lancifolia. These studies indicated that the cleaner removed oil from marsh grasses and alleviated the short-term impact of oil on gas exchange function of the study plants. However, use of cleaner had no detectable effects on above-ground biomass production or regeneration at the end of the first growing season in S. patens. Similarly, no beneficial effects of cleaner on carbon fixation and number of live shoots were apparent beyond 12 weeks in S. lancifolia.

  11. Flora characteristics of Chenier Wetland in Bohai Bay and biogeographic relations with adjacent wetlands

    Science.gov (United States)

    Zhao, Yanyun; Lu, Zhaohua; Liu, Jingtao; Hu, Shugang

    2017-12-01

    A key step towards the restoration of heavily disturbed fragile coastal wetland ecosystems is determining the composition and characteristics of the plant communities involved. This study determined and characterized the community of higher plants in the Chenier wetland of Bohai Bay using a combination of field surveys, quadrat approaches, and multivariate statistical analyses. This community was then compared to other adjacent wetlands (Tianjin, Qinhuangdao, Laizhouwan, Jiaozhouwan, and Yellow River Delta wetland) located near the Huanghai and Bohai Seas using principal coordinate analysis (PCoA). Results showed a total of 56 higher plant species belonging to 52 genera from 20 families in Chenier wetland, the majority of which were dicotyledons. Single-species families were predominant, while larger families, including Gramineae, Compositae, Leguminosae, and Chenopodiaceae contained a higher number of species (each⩾6 species). Cosmopolitan species were also dominant with apparent intrazonality. Abundance (number of species) of temperate species was twice that of tropical taxa. Species number of perennial herbs, such as Gramineae and Compositae, was generally higher. Plant diversity in the Chenier wetland, based on the Shannon-Wiener index, was observed to be between the Qinhuangdao and Laizhouwan indices, while no significant difference was found in other wetlands using the Simpson index. Despite these slight differences in diversity, PCoA based on species abundance and composition of the wetland flora suggest that the Bohai Chenier community was highly similar to the coastal wetlands in Tianjin and Laizhouwan, further suggesting that these two wetlands could be important breeding grounds and resources for the restoration of the plant ecosystem in the Chenier wetland.

  12. Impact of chromium and aluminium pollution on the diversity of zooplankton: a case study in the Chimaliapan wetland (Ramsar site) (Lerma basin, Mexico).

    Science.gov (United States)

    García-García, Gerardo; Nandini, S; Sarma, S S S; Martínez-Jerónimo, Fernando; Jiménez-Contreras, Jorge

    2012-01-01

    Biological monitoring and the use of biotic indices are important in evaluating the health of aquatic systems. However, zooplankton are rarely included in biomonitoring protocols. We conducted a one-year study (March 2008-February 2009) at two sites from the Chimaliapan wetland, with concentrations of aluminium (Al) and chromium (Cr) above and within the permissible limits, respectively. Metals in the sediment and water were analyzed from three locations per site every two months. In addition to analyses of the abundance and diversity of rotifers, cladocerans and copepods, we sampled 11 physicochemical variables in the water and six from the sediments. The metal concentration in the polluted site (significantly above the permissible limits) ranged between 7266-8174 mg Kg(-1) of Al and 14.6-18.3 mg Kg(-1) of Cr. We found 92 species of rotifers, cladocerans and copepods. The Brillouin index for both sites ranged from 3.9-5.4, the Shannon-Wiener index from 4.2-5.5 while the Brachionus-Trichocerca ratio ranged between 1.0 and 1.7. The Wetland Zooplankton Index was significantly different among the sites; 2.63 at site 1 and 2.13 at site 2. The saprobic index was 3.2 for both sites. Data analyses using multifactorial techniques suggested that zooplankton can be used to evaluate the impact of the metals aforementioned, since these organisms are generally more sensitive than other groups and also have a high ecological relevance.

  13. Helminth communities of two species of piscivorous birds, Ardea alba (Linnaeus) and Nyctanassa violacea (Gmelin) (Ciconiiformes: Ardeidae), in two coastal lagoons from Guerrero state, Mexico.

    Science.gov (United States)

    Violante-González, Juan; Monks, Scott; Gil-Guerrero, Salvador; Rojas-Herrera, Agustín A; Flores-Rodríguez, Pedro

    2012-07-01

    The composition and species richness in helminth communities of two species of heron, Ardea alba and Nyctanassa violacea, in two coastal lagoons from Guerrero, Mexico were examined. Nineteen species of helminth (7,804 individuals) were identified in 43 adult birds: 15 digeneans, 1 acanthocephalan, 1 cestode, and 2 nematodes. Eight species co-occurred in herons of both species and lagoons. The prevalence values of seven species and the mean abundance of five species varied significantly between species of birds and between lagoons. The heterophyid, Ascocotyle (Phagicola) longa, was the helminth numerically dominant in the helminth community of A. alba in both lagoons, while the cestode, Parvitaenia cochlearii, dominated the community of N. violacea. At the component community level, species richness varied significantly: 10 species in A. alba from Coyuca to 16 in N. violacea (Tres Palos). All of the birds examined were infected with helminth parasites: three to seven species per host in A. alba from Coyuca, and two to eight species in A. alba and N. violacea from Tres Palos. The results indicate that even though species composition was similar between both species of heron, the structure of their communities was not the same. Differences in the feeding behavior of the birds (day/night habits), as well as local differences in the abundance of species of fish, and infection levels of helminths in each lagoon are suggested as being responsible for the variations registered in the structure of the helminth communities.

  14. Limnological and botanical characterization of larval habitats for two primary malarial vectors, Anopheles albimanus and Anopheles pseudopunctipennis, in coastal areas of Chiapas State, Mexico.

    Science.gov (United States)

    Savage, H M; Rejmankova, E; Arredondo-Jim'enez, J I; Roberts, D R; Rodr'iguez, M H

    1990-12-01

    Field surveys of mosquito breeding sites on the Pacific coastal plain and foothill regions of southern Chiapas, Mexico, were carried out in the dry and wet seasons of 1988. At each site, selected environmental variables were measured or estimated, presence and percent cover of aquatic plants recorded, a water sample collected for subsequent analyses, and 10-30 dips made for mosquito larvae. Logistic regression and discriminant analyses revealed that the occurrence of Anopheles albimanus larvae in both the wet and dry seasons was positively associated with planktonic algae and negatively associated with altitude. In the dry season, An. albimanus larvae were largely restricted to the margins of permanent water bodies and were associated with the presence of floating plants, particularly Eichhornia crassipes. During the wet season An. albimanus larvae were positively associated with emergent plants, particularly seasonally flooded Cyperaceae, and phosphorus (PO4) concentrations, and were negatively associated with abundant filamentous algae, high levels of total suspended solids (TSS) and Salvinia. In the dry season, An. pseudopunctipennis larvae were positively associated with filamentous algae, altitude and the presence of Heteranthera if encountered in a riverine setting, and were negatively associated with water depth. During the wet season, flooding eliminated typical flood plain An. pseudopunctipennis habitats, and larvae were rarely encountered.

  15. Joint Calibration of Submarine Groundwater Discharge (SGD) with Tidal Pumping: Modeling Variable-density Groundwater Flow in Unconfined Coastal Aquifer of Apalachee Bay, Gulf of Mexico

    Science.gov (United States)

    Li, X.; Hu, B.; Burnett, W.; Santos, I.

    2008-05-01

    Submarine Groundwater Discharge (SGD) as an unseen phenomenon is now recognized as an important pathway between land and sea. These discharges typically display significant spatial and temporal variability making quantification difficult. Groundwater seepage is patchy, diffuse, and temporally variable, and thus makes the estimation of its magnitude and components is a challenging enterprise. A two-dimensional hydrogeological model is developed to the near-shore environment of an unconfined aquifer at a Florida coastal area in the northeastern Gulf of Mexico. Intense geological survey and slug tests are set to investigate the heterogeneity of this layered aquifer. By applying SEAWAT2000, considering the uncertainties caused by changes of boundary conditions, a series of variable-density-flow models incorporates the tidal-influenced seawater recirculation and the freshwater-saltwater mixing zone under the dynamics of tidal pattern, tidal amplitude and variation of water table. These are thought as the contributing factors of tidal pumping and hydraulic gradient which are the driven forces of SGD. A tidal-influenced mixing zone in the near-shore aquifer shows the importance of tidal mechanism to flow and salt transport in the process of submarine pore water exchange. Freshwater ratio in SGD is also analyzed through the comparison of Submarine Groundwater Recharge and freshwater inflow. The joint calibration with other methods (natural tracer model and seepage meter) is also discussed.

  16. Working group report on wetlands, wildlife and fisheries

    International Nuclear Information System (INIS)

    Maltby, L.

    1990-01-01

    A workshop was held to discuss the impacts of climatic change on wetlands, wildlife and fisheries. Impacts that could occur as a result of climatic change include: sea level rise affecting coastal wetlands by inundation, erosion and saltwater intrusion; temperature rise/moisture balance changes on other wetlands; lake level changes affecting shoreline wetlands; vegetation species/community modification of biological systems; and changes in values derived from wetlands impacting socio-economic systems. The Great Lakes shoreline is considered to be at high risk, and it is predicted that there will be profound effects on the ecological and socio-economic value of the Great Lakes wetlands. Presentations were given on wildlife as biological indicators, modelling the effects of climate warming on the stream habitats of brook trout, and the effects of an altered water regime on Great Lakes coastal wetlands. It was concluded that a fundamental research program of an interdisciplinary nature be established to determine current linkages of climatic variables to the function, distribution and productivity of wetlands and associated fish and wildlife resources. A national wetlands monitoring network should be established to trace the influence of climatic variables on wetlands and fish, to identify environmental indicators for reporting and to complement other monitoring programs

  17. Exploring drivers of wetland hydrologic fluxes across parameters and space

    Science.gov (United States)

    Jones, C. N.; Cheng, F. Y.; Mclaughlin, D. L.; Basu, N. B.; Lang, M.; Alexander, L. C.

    2017-12-01

    Depressional wetlands provide diverse ecosystem services, ranging from critical habitat to the regulation of landscape hydrology. The latter is of particular interest, because while hydrologic connectivity between depressional wetlands and downstream waters has been a focus of both scientific research and policy, it remains difficult to quantify the mode, magnitude, and timing of this connectivity at varying spatial and temporary scales. To do so requires robust empirical and modeling tools that accurately represent surface and subsurface flowpaths between depressional wetlands and other landscape elements. Here, we utilize a parsimonious wetland hydrology model to explore drivers of wetland water fluxes in different archetypal wetland-rich landscapes. We validated the model using instrumented sites from regions that span North America: Prairie Pothole Region (south-central Canada), Delmarva Peninsula (Mid-Atlantic Coastal Plain), and Big Cypress Swamp (southern Florida). Then, using several national scale datasets (e.g., National Wetlands Inventory, USFWS; National Hydrography Dataset, USGS; Soil Survey Geographic Database, NRCS), we conducted a global sensitivity analysis to elucidate dominant drivers of simulated fluxes. Finally, we simulated and compared wetland hydrology in five contrasting landscapes dominated by depressional wetlands: prairie potholes, Carolina and Delmarva bays, pocosins, western vernal pools, and Texas coastal prairie wetlands. Results highlight specific drivers that vary across these regions. Largely, hydroclimatic variables (e.g., PET/P ratios) controlled the timing and magnitude of wetland connectivity, whereas both wetland morphology (e.g., storage capacity and watershed size) and soil characteristics (e.g., ksat and confining layer depth) controlled the duration and mode (surface vs. subsurface) of wetland connectivity. Improved understanding of the drivers of wetland hydrologic connectivity supports enhanced, region

  18. Fouling communities and degradation of archeological metals in the coastal sea of the Southwestern Gulf of Mexico.

    Science.gov (United States)

    López Garrido, Pedro H; González-Sánchez, J; Escobar Briones, Elva

    2015-01-01

    Corrosion and biofouling phenomena of cast iron and brass were evaluated under natural conditions to determine the degradation process of archeological artifacts. Field exposure studies of experimental materials were conducted over 15 months at an offshore position in the sea of Campeche in the Gulf of Mexico. Corrosion was determined by gravimetric measurements. The community structure of the benthic assemblage inhabiting the surfaces of both materials was evaluated. A total of 53 species was identified. The community in both cases was composed of a small number of species. Encrusting, attached and erect life forms were dominant on iron. Attached life forms were dominant on brass. Biofouling produced a decrease in the weight loss measurements of cast iron samples. Biofouling provided a beneficial factor for in situ preservation of iron archeological artifacts in wreck sites.

  19. 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...

  20. Total mercury in muscles and liver of Mugil spp. from three coastal lagoons of NW Mexico: concentrations and risk assessment.

    Science.gov (United States)

    Delgado-Alvarez, C G; Frías-Espericueta, M G; Ruelas-Inzunza, J; Becerra-Álvarez, M J; Osuna-Martínez, C C; Aguilar-Juárez, M; Osuna-López, J I; Escobar-Sánchez, O; Voltolina, D

    2017-07-01

    Total mercury (Hg) concentrations were determined by atomic absorption spectrophotometry in muscles and liver of composite samples of Mugil cephalus and M. curema collected during November 2013 and in January, April, and July 2014 from the coastal lagoons Altata-Ensenada del Pabellón (AEP), Ceuta (CEU), and Teacapán-Agua Brava (TAG) of Sinaloa State. The mean Hg contents and information on local consumption were used to assess the possible risk caused by fish ingestion. Mean total mercury levels in the muscles ranged from 0.11 to 0.39 μg/g, while the range for liver was 0.12-3.91 μg/g. The mean Hg content of the liver was significantly (p mercury calculated for the younger age classes of one fishing community were >1, indicating a possible risk for some fishing communities of the Mexican Pacific coast.

  1. Diversity and structure of periphyton and metaphyton diatom communities in a tropical wetland in Mexico Diversidad y estructura de las comunidades de diatomeas del perifiton y el metafiton en un humedal tropical en México

    Directory of Open Access Journals (Sweden)

    Claudia Ibarra

    2009-12-01

    Full Text Available We investigated the structure and diversity of diatoms in communities of metaphyton and periphyton from the wetland of El Edén Ecological Reserve, Quintana Roo, Mexico. In spite of the close association and communication between these communities, our comparisons reveal that the 2 communities have distinct species assemblages, with the periphyton being more diverse overall. We fit abundance curves for periphyton and metaphyton, and argue that our results are consistent with communities where environmental conditions play a more important role than competition in structuring diatom species assemblages.Investigamos la estructura y la diversidad de las comunidades de diatomeas en el metafiton y el perifiton del humedal de la Reserva Ecológica El Edén, Quintana Roo, México. A pesar de la cercana asociación entre estas comunidades, nuestro análisis revela que tanto el perifiton como el metafiton consisten de distintas asociaciones de especies y el perifiton es el más diverso. Las distribuciones de las abundancias de las especies de diatomeas satisfacen curvas de distribución log-normal; esto significa que en las comunidades estudiadas, las condiciones ambientales juegan un papel más importante que la competencia para determinar su estructura.

  2. A complex-systems approach to predicting effects of sea level rise and nitrogen loading on nitrogen cycling in coastal wetland ecosystems

    Science.gov (United States)

    Larsen, Laurel G.; Moseman, Serena; Santoro, Alyson; Hopfensperger, Kristine; Burgin, Amy

    2010-01-01

    To effectively manage coastal ecosystems, we need an improvedunderstanding of how tidal marsh ecosystem services will respond to sea-level rise and increased nitrogen (N) loading to coastal areas. Here we review existing literature to better understand how these interacting perturbations s will likely impact N removal by tidal marshes. We propose that the keyy factors controlling long-term changes in N removal are plant-community changes, soil accretion rates, surface-subsurface flow paths, marsh geomorphology microbial communities, and substrates for microbial reactions. Feedbacks affecting relative elevations and sediment accretion ratess will serve as dominant controls on future N removal throughout the marsh. Given marsh persistence, we hypothesize that the processes dominating N removal will vary laterally across the marsh and longitudinallyalong the estuarine gradient. In salt marsh interiors, where nitrate reduction rates are often limited by delivery of nitrate to bacterial communities, reductions in groundwater discharge due to sea level rise may trigger a net reduction in N removal. In freshwater marshes, we expect a decreasee in N removal efficiency due to increased sulfide concentrations. Sulfide encroachment will increase the relative importance of dissimilatory nitrate reduction to ammonium and lead to greater bacterial nitrogen immobilization, ultimately resulting in an ecosystem that retains more N and is less effective at permanent N removal from the watershed. In contrast, we predict that sealevel–driven expansion of the tidal creek network and the degree of surface-subsurface exchange flux through tidal creek banks will result in greater N-removal efficiency from these locations.

  3. Environmental and economic assessment of discharges from Gulf of Mexico region oil and gas operations

    International Nuclear Information System (INIS)

    Gettleson, D.A.

    1993-01-01

    Continental Shelf Associates, Inc. (CSA) was contracted to conduct a three-year study of the environmental and health related impacts of produced water and sand discharges from oil and gas operations. Data on naturally occurring radioactive materials (NORM), heavy metals, and hydrocarbons in water, sediment, and biota will be collected and evaluated. Health related impacts will be studied through field collections and analyses of commercially- and recreationally-important fish and shellfish tissues. Additionally, information on seafood catch, consumption, and use patterns for the Gulf of Mexico will be gathered and analyzed. The facilities to be studied will include both offshore and coastal facilities in the Gulf of Mexico. Coastal sites will be additionally studied to determine ecological recovery of impacted wetland and open bay areas. The economic impact of existing and proposed effluent federal and state regulations will also be evaluated. The primary objectives of the project are to increase the base of scientific knowledge concerning (1) the fate and environmental effects of organics, trace metals, and NORM in water, sediment, and biota near several offshore oil and gas facilities; (2) the characteristics of produced water and produced sand discharges as they pertain to organics, trace metals, and NORM variably found in association with the discharges; (3) the recovery of four terminated produced water discharge sites located in wetland and high-energy open bay sites of coastal Louisiana and Texas; (4) the economic and energy supply impacts of existing and anticipated federal and state offshore and coastal discharge regulations; and (5) the catch, consumption and human use patterns of seafood species collected from coastal and offshore waters. Accomplishments for this period are described

  4. Satellite Assessment of Bio-Optical Properties of Northern Gulf of Mexico Coastal Waters Following Hurricanes Katrina and Rita.

    Science.gov (United States)

    Lohrenz, Steven E; Cai, Wei-Jun; Chen, Xiaogang; Tuel, Merritt

    2008-07-10

    The impacts of major tropical storms events on coastal waters include sediment resuspension, intense water column mixing, and increased delivery of terrestrial materials into coastal waters. We examined satellite imagery acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) ocean color sensor aboard the Aqua spacecraft following two major hurricane events: Hurricane Katrina, which made landfall on 29 August 2005, and Hurricane Rita, which made landfall on 24 September. MODIS Aqua true color imagery revealed high turbidity levels in shelf waters immediately following the storms indicative of intense resuspension. However, imagery following the landfall of Katrina showed relatively rapid return of shelf water mass properties to pre-storm conditions. Indeed, MODIS Aqua-derived estimates of diffuse attenuation at 490 nm (K_490) and chlorophyll (chlor_a) from mid-August prior to the landfall of Hurricane Katrina were comparable to those observed in mid-September following the storm. Regions of elevated K_490 and chlor_a were evident in offshore waters and appeared to be associated with cyclonic circulation (cold-core eddies) identified on the basis of sea surface height anomaly (SSHA). Imagery acquired shortly after Hurricane Rita made landfall showed increased water column turbidity extending over a large area of the shelf off Louisiana and Texas, consistent with intense resuspension and sediment disturbance. An interannual comparison of satellite-derived estimates of K_490 for late September and early October revealed relatively lower levels in 2005, compared to the mean for the prior three years, in the vicinity of the Mississippi River birdfoot delta. In contrast, levels above the previous three year mean were observed off Texas and Louisiana 7-10 d after the passage of Rita. The lower values of K_490 near the delta could be attributed to relatively low river discharge during the preceding months of the 2005 season. The elevated levels off Texas and

  5. Satellite Assessment of Bio-Optical Properties of Northern Gulf of Mexico Coastal Waters Following Hurricanes Katrina and Rita

    Directory of Open Access Journals (Sweden)

    Merritt Tuel

    2008-07-01

    Full Text Available The impacts of major tropical storms events on coastal waters include sediment resuspension, intense water column mixing, and increased delivery of terrestrial materials into coastal waters. We examined satellite imagery acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS ocean color sensor aboard the Aqua spacecraft following two major hurricane events: Hurricane Katrina, which made landfall on 29 August 2005, and Hurricane Rita, which made landfall on 24 September. MODIS Aqua true color imagery revealed high turbidity levels in shelf waters immediately following the storms indicative of intense resuspension. However, imagery following the landfall of Katrina showed relatively rapid return of shelf water mass properties to pre-storm conditions. Indeed, MODIS Aqua-derived estimates of diffuse attenuation at 490 nm (K_490 and chlorophyll (chlor_a from mid-August prior to the landfall of Hurricane Katrina were comparable to those observed in mid-September following the storm. Regions of elevated K_490 and chlor_a were evident in offshore waters and appeared to be associated with cyclonic circulation (cold-core eddies identified on the basis of sea surface height anomaly (SSHA. Imagery acquired shortly after Hurricane Rita made landfall showed increased water column turbidity extending over a large area of the shelf off Louisiana and Texas, consistent with intense resuspension and sediment disturbance. An interannual comparison of satellite-derived estimates of K_490 for late September and early October revealed relatively lower levels in 2005, compared to the mean for the prior three years, in the vicinity of the Mississippi River birdfoot delta. In contrast, levels above the previous three year mean were observed off Texas and Louisiana 7-10 d after the passage of Rita. The lower values of K_490 near the delta could be attributed to relatively low river discharge during the preceding months of the 2005 season. The elevated levels

  6. [Benthic flora and reproduction of Batophora spp. algae (Chlorophyta: Dasycladaceae) in a polluted coastal lagoon (Chetumal Bay, Mexico)].

    Science.gov (United States)

    Quan-Young, L I; Jiménez-Flores, S G; Espinoza-Avalos, J

    2006-06-01

    The benthic flora, and the vegetative and reproductive characters of the algae Batophora oerstedii and B. occidentalis (Chlorophyta) were recorded from five sites of Chetumal Bay, Quintana Roo, Mexico. A sewage gradient has been reported along those sites. Plants were sampled in May and October 1999, which corresponded to dry and rainy seasons, respectively. Forty taxa were found, 11 are new records for the Chetumal Bay, and 6 are new records for the Mexican Caribbean. Enteromorpha species were present in sites known as rich in organic matter (both from anthropogenic and natural sources). Batophora spp. is the dominant algae in all Chetumal Bay. However, it was absent next to sewage outfalls. The morphological characters of B. oerstedii and B. occidentalis did not change significantly along the sites reported as polluted. The length and width of gametophores, as well as the diameter of the gametangia were clearly different for both species. Different reproductive strategies may help B. oerstedii and B. occidentalis to closely coexist in the Chetumal Bay.

  7. Movement patterns of Antillean manatees in Chetumal Bay (Mexico) and coastal Belize: A challenge for regional conservation

    Science.gov (United States)

    Castelblanco-Martínez, Delma Nataly; Padilla-Saldivar, J.; Hernández-Arana, Héctor Abuid; Slone, D.H.; Reid, J.P.; Morales-Vela, B.

    2013-01-01

    Information from 15 satellite-tracked Antillean manatees (Trichechus manatus manatus) was analyzed in order to assess individual movements, home ranges, and high-use areas for conservation decisions. Manatees were captured in Chetumal Bay, Mexico, and tagged with Argos-monitored satellite transmitters. Location of the manatees and physical characteristics were assessed to describe habitat properties. Most manatees traveled to freshwater sources. The Maximum Area Size (MAS) for each manatee was determined using the observation-area method. Additional kernel densities of 95% home range and 50% Center of Activity (COA) were also calculated, with manatees having 1–3 COAs. Manatees exhibited two different movement patterns: remaining in Chetumal Bay, and long-distance (up to 240 km in 89 d). The residence time in Chetumal Bay was higher for females (89.6% of time) than for males (72.0%), but the daily travel rate (0.4–0.5 km/d) was similar for both sexes. Most of the COAs fell within Natural Protected Areas (NPA). However, manatees also travel for long distances into unprotected areas, where they face uncontrolled boat traffic, fishing activities, and habitat loss. Conservation of movement corridors may promote long-distance movements and facilitate genetic exchange.

  8. Mapping Satellite Inherent Optical Properties Index in Coastal Waters of the Yucatán Peninsula (Mexico

    Directory of Open Access Journals (Sweden)

    Jesús A. Aguilar-Maldonado

    2018-06-01

    Full Text Available The Yucatán Peninsula hosts worldwide-known tourism destinations that concentrate most of the Mexico tourism activity. In this region, tourism has exponentially increased over the last years, including wildlife oriented tourism. Rapid tourism development, involving the consequent construction of hotels and tourist commodities, is associated with domestic sewage discharges from septic tanks. In this karstic environment, submarine groundwater discharges are very important and highly vulnerable to anthropogenic pollution. Nutrient loadings are linked to harmful algal blooms, which are an issue of concern to local and federal authorities due to their recurrence and socioeconomic and human health costs. In this study, we used satellite products from MODIS (Moderate Resolution Imaging Spectroradiometer to calculate and map the satellite Inherent Optical Properties (IOP Index. We worked with different scenarios considering both holiday and hydrological seasons. Our results showed that the satellite IOP Index allows one to build baseline information in a sustainable mid-term or long-term basis which is key for ecosystem-based management.

  9. Spatial and temporal structure of fish assemblages in a hyperhaline coastal system: Ría Lagartos, Mexico

    Directory of Open Access Journals (Sweden)

    Miguel Angel Peralta-Meixueiro

    Full Text Available The spatial and temporal fish species assemblages were analyzed throughout two annual cycles (2004-2005 and 2007-2008 in the Ría Lagartos Lagoon system, Mexico, via non-parametric multivariate analyses. We compared density and biomass of fish species among five habitat types defined by combinations of structure and environmental characteristics (hyperhaline, rocky, seagrass, channel, and marine, and three climatic seasons (dry, rainy, and northerlies. A total of 11,187 individuals distributed in 32 families and 63 species were collected. The most numerically abundant species were Floridichthys polyommus and Cyprinodon artifrons, while Sphoeroides testudineus contributed to the greatest biomass. Species composition consisted mainly of estuarine and euryhaline marine species. Spatially, a saline gradient was observed with marine conditions in the mouth, and increasing to over 100 in the inner zone of the system. Species richness, diversity and biomass declined from the mouth to the inner zone, while density showed an inverse tendency, with the highest values in the inner zone. Thus the salinity was the variable that best explained the spatial fish assemblages" structure. The ichthyofauna composition did not change over time, but the dominant species varied with the years. The abundance of juvenile specimens, suggest that the different habitats are used as feeding and breeding zones; hence it is proposed that protection strategies be pursued not only for the lagoon system but also for the northern zone of the Yucatan Peninsula.

  10. National Wetlands Inventory Points

    Data.gov (United States)

    Minnesota Department of Natural Resources — Wetland point features (typically wetlands that are too small to be as area features at the data scale) mapped as part of the National Wetlands Inventory (NWI). The...

  11. National Wetlands Inventory Polygons

    Data.gov (United States)

    Minnesota Department of Natural Resources — Wetland area features mapped as part of the National Wetlands Inventory (NWI). The National Wetlands Inventory is a national program sponsored by the US Fish and...

  12. CURRENT DIRECTION, SALINITY - SURFACE WATER and other data from DRIFTING PLATFORM in the Gulf of Mexico and Coastal Waters of Gulf of Mexico from 1992-08-13 to 1995-08-05 (NODC Accession 9600132)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The water depth and temperature data were collected in Gulf of Mexico as part of Louisiana-Texas (LATEX part C Lousiana and Texas: LaTex) Gulf of Mexico Eddy...

  13. Mercury Speciation at a Coastal Site in the Northern Gulf of Mexico: Results from the Grand Bay Intensive Studies in Summer 2010 and Spring 2011

    Directory of Open Access Journals (Sweden)

    Xinrong Ren

    2014-04-01

    , which is located in a coastal environment of the Gulf of Mexico, experienced impacts from mercury sources that are both local and regional in nature.

  14. PRESSURE - WATER and Other Data from AIRCRAFT From Coastal Waters of Gulf of Mexico from 19941015 to 19941115 (NODC Accession 9500101)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The water depth and temperature data were collected in Gulf of Mexico as part of Louisiana-Texas (LATEX part C) Gulf of Mexico Eddy Circulation Study from aircraft...

  15. Kansas Playa Wetlands

    Data.gov (United States)

    Kansas Data Access and Support Center — This digital dataset provides information about the distribution, areal extent, and morphometry of playa wetlands throughout western Kansas. Playa wetlands were...

  16. Dissolved carbon dynamics in the freshwater-saltwater mixing zone of a coastal river entering the Northern Gulf of Mexico

    Science.gov (United States)

    He, S.; Xu, Y. J.

    2017-12-01

    Estuaries play an important role in the dynamics of dissolved carbon from freshwater to marine systems. This study aims to determine how dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC) concentrations change along an 88-km long estuarine river with salinity ranging from 0.02 to 29.50. The study is expected to elucidate which processes most likely control carbon dynamics in a freshwater-saltwater mixing system, and to evaluate the net metabolism of this estuary using mixing curves and stable isotope analyses. From November 2014 to February 2016, water samples were collected and in-situ measurements on ambient water conditions were performed during eighteen field trips at six sites from upstream to downstream of the Calcasieu River, which enters the Northern Gulf of Mexico in the southern United States. δ13CDIC and δ13CDOC were measured from May 2015 to February 2017 during five of the field trips. The DIC concentration and δ13CDIC increased rapidly with increasing salinity in the mixing zone. The DIC concentrations appeared to be largely influenced by conservative mixing. The δ13CDIC values were close to those suggested by the conservative mixing model for May 2015, June 2015 and November 2015, but lower than those for July 2015 and February 2016, suggesting that an estuarine river can fluctuate from a balanced to a heterotrophic system (i.e., production/respiration aquatic photosynthesis from carbon produced by terrestrial photosynthesis in a river-ocean continuum. These findings suggest that riverine dissolved carbon undergoes a rapid change in freshwater-saltwater mixing, and that these dynamics should be taken into account in carbon processing and budgeting in the world's estuarine systems.

  17. Fractionation and risk assessment of Fe and Mn in surface sediments from coastal sites of Sonora, Mexico (Gulf of California).

    Science.gov (United States)

    Jara-Marini, Martín E; García-Camarena, Raúl; Gómez-Álvarez, Agustín; García-Rico, Leticia

    2015-07-01

    The aim of this study was to evaluate Fe and Mn distribution in geochemical fractions of the surface sediment of four oyster culture sites in the Sonora coast, Mexico. A selective fractionation scheme to obtain five fractions was adapted for the microwave system. Surface sediments were analyzed for carbonates, organic matter contents, and Fe and Mn in geochemical fractions. The bulk concentrations of Fe ranged from 10,506 to 21,918 mg/kg (dry weight, dry wt), and the bulk concentrations of Mn ranged from 185.1 to 315.9 mg/kg (dry wt) in sediments, which was low and considered as non-polluted in all of the sites. The fractionation study indicated that the major geochemical phases for the metals were the residual, as well as the Fe and Mn oxide fractions. The concentrations of metals in the geochemical fractions had the following order: residual > Fe and Mn oxides > organic matter > carbonates > interchangeable. Most of the Fe and Mn were linked to the residual fraction. Among non-residual fractions, high percentages of Fe and Mn were linked to Fe and Mn oxides. The enrichment factors (EFs) for the two metals were similar in the four studied coasts, and the levels of Fe and Mn are interpreted as non-enrichment (EF < 1) because the metals concentrations were within the baseline concentrations. According to the environmental risk assessment codes, Fe and Mn posed no risk and low risk, respectively. Although the concentrations of Fe and Mn were linked to the residual fraction, the levels in non-residual fractions may significantly result in the transference of other metals, depending on several physico-chemical and biological factors.

  18. Bacterial community shift in the coastal Gulf of Mexico salt-marsh sediment microcosm in vitro following exposure to the Mississippi Canyon Block 252 oil (MC252)

    KAUST Repository

    Koo, Hyunmin; Mojib, Nazia; Huang, Jonathan P.; Donahoe, Rona J.; Bej, Asim K.

    2014-01-01

    In this study, we examined the responses by the indigenous bacterial communities in salt-marsh sediment microcosms in vitro following treatment with Mississippi Canyon Block 252 oil (MC252). Microcosms were constructed of sediment and seawater collected from Bayou La Batre located in coastal Alabama on the Gulf of Mexico. We used an amplicon pyrosequencing approach on microcosm sediment metagenome targeting the V3–V5 region of the 16S rRNA gene. Overall, we identified a shift in the bacterial community in three distinct groups. The first group was the early responders (orders Pseudomonadales and Oceanospirillales within class Gammaproteobacteria), which increased their relative abundance within 2 weeks and were maintained 3 weeks after oil treatment. The second group was identified as early, but transient responders (order Rhodobacterales within class Alphaproteobacteria; class Epsilonproteobacteria), which increased their population by 2 weeks, but returned to the basal level 3 weeks after oil treatment. The third group was the late responders (order Clostridiales within phylum Firmicutes; order Methylococcales within class Gammaproteobacteria; and phylum Tenericutes), which only increased 3 weeks after oil treatment. Furthermore, we identified oil-sensitive bacterial taxa (order Chromatiales within class Gammaproteobacteria; order Syntrophobacterales within class Deltaproteobacteria), which decreased in their population after 2 weeks of oil treatment. Detection of alkane (alkB), catechol (C2,3DO) and biphenyl (bph) biodegradation genes by PCR, particularly in oil-treated sediment metacommunity DNA, delineates proliferation of the hydrocarbon degrading bacterial community. Overall, the indigenous bacterial communities in our salt-marsh sediment in vitro microcosm study responded rapidly and shifted towards members of the taxonomic groups that are capable of surviving in an MC252 oil-contaminated environment.

  19. Bacterial community shift in the coastal Gulf of Mexico salt-marsh sediment microcosm in vitro following exposure to the Mississippi Canyon Block 252 oil (MC252)

    KAUST Repository

    Koo, Hyunmin

    2014-07-10

    In this study, we examined the responses by the indigenous bacterial communities in salt-marsh sediment microcosms in vitro following treatment with Mississippi Canyon Block 252 oil (MC252). Microcosms were constructed of sediment and seawater collected from Bayou La Batre located in coastal Alabama on the Gulf of Mexico. We used an amplicon pyrosequencing approach on microcosm sediment metagenome targeting the V3–V5 region of the 16S rRNA gene. Overall, we identified a shift in the bacterial community in three distinct groups. The first group was the early responders (orders Pseudomonadales and Oceanospirillales within class Gammaproteobacteria), which increased their relative abundance within 2 weeks and were maintained 3 weeks after oil treatment. The second group was identified as early, but transient responders (order Rhodobacterales within class Alphaproteobacteria; class Epsilonproteobacteria), which increased their population by 2 weeks, but returned to the basal level 3 weeks after oil treatment. The third group was the late responders (order Clostridiales within phylum Firmicutes; order Methylococcales within class Gammaproteobacteria; and phylum Tenericutes), which only increased 3 weeks after oil treatment. Furthermore, we identified oil-sensitive bacterial taxa (order Chromatiales within class Gammaproteobacteria; order Syntrophobacterales within class Deltaproteobacteria), which decreased in their population after 2 weeks of oil treatment. Detection of alkane (alkB), catechol (C2,3DO) and biphenyl (bph) biodegradation genes by PCR, particularly in oil-treated sediment metacommunity DNA, delineates proliferation of the hydrocarbon degrading bacterial community. Overall, the indigenous bacterial communities in our salt-marsh sediment in vitro microcosm study responded rapidly and shifted towards members of the taxonomic groups that are capable of surviving in an MC252 oil-contaminated environment.

  20. USGS assessment of undiscovered oil and gas resources in Paleogene strata of the U.S. Gulf of Mexico coastal plain and state waters

    Science.gov (United States)

    Warwick, Peter D.; Coleman, James; Hackley, Paul C.; Hayba, Daniel O.; Karlsen, Alexander W.; Rowan, Elisabeth L.; Swanson, Sharon M.; Kennan, Lorcan; Pindell, James; Rosen, Norman C.

    2007-01-01

    This report presents a review of the U.S. Geological Survey (USGS) 2007 assessment of the undiscovered oil and gas resources in Paleogene strata underlying the U.S. Gulf of Mexico Coastal Plain and state waters. Geochemical, geologic, geophysical, thermal maturation, burial history, and paleontologic studies have been combined with regional cross sections and data from previous USGS petroleum assessments have helped to define the major petroleum systems and assessment units. Accumulations of both conventional oil and gas and continuous coal-bed gas within these petroleum systems have been digitally mapped and evaluated, and undiscovered resources have been assessed following USGS methodology.The primary source intervals for oil and gas in Paleogene (and Cenozoic) reservoirs are coal and shale rich in organic matter within the Wilcox Group (Paleocene-Eocene) and Sparta Formation of the Claiborne Group (Eocene); in addition, Cretaceous and Jurassic source rocks probably have contributed substantial petroleum to Paleogene (and Cenozoic) reservoirs.For the purposes of the assessment, Paleogene strata have divided into the following four stratigraphic study intervals: (1) Wilcox Group (including the Midway Group and the basal Carrizo Sand of the Claiborne Group; Paleocene-Eocene); (2) Claiborne Group (Eocene); (3) Jackson and Vicksburg Groups (Eocene-Oligocene); and (4) the Frio-Anahuac Formations (Oligocene). Recent discoveries of coal-bed gas in Paleocene strata confirm a new petroleum system that was not recognized in previous USGS assessments. In total, 26 conventional Paleogene assessment units are defined. In addition, four Cretaceous-Paleogene continuous (coal-bed gas) assessment units are included in this report. Initial results of the assessment will be released as USGS Fact Sheets (not available at the time of this writing).Comprehensive reports for each assessment unit are planned to be released via the internet and distributed on CD-ROMs within the next year.

  1. Modeling the climatic and subsurface stratigraphy controls on the hydrology of a Carolina Bay wetland in South Carolina, USA

    Science.gov (United States)

    Ge Sun; Timothy J. Callahan; Jennifer E. Pyzoha; Carl C. Trettin

    2006-01-01

    Restoring depressional wetlands or geographically isolated wetlands such as cypress swamps and Carolina bays on the Atlantic Coastal Plains requires a clear understanding of the hydrologic processes and water balances. The objectives of this paper are to (1) test a distributed forest hydrology model, FLATWOODS, for a Carolina bay wetland system using seven years of...

  2. Modeling the climatic and subsurface stratigraphy controls on the hydrology of a Carolina bay wetland in South Carolina, USA

    Science.gov (United States)

    Ge Sun; Timothy J. Callahan; Jennifer E. Pyzoha; Carl C. Trettin

    2006-01-01

    Restoring depressional wetlands or geographically isolated wetlands such as cypress swamps and Carolina bays on the Atlantic Coastal Plains requires a clear understanding of the hydrologic processes and water balances. The objectives of this paper are to (1) test a distributed forest hydrology model, FLATWOODS, for a Carolina bay wetland system using seven years of...

  3. Characterization of Archaeological Sediments Using Fourier Transform Infrared (FT-IR) and Portable X-ray Fluorescence (pXRF): An Application to Formative Period Pyro-Industrial Sites in Pacific Coastal Southern Chiapas, Mexico.

    Science.gov (United States)

    Neff, Hector; Bigney, Scott J; Sakai, Sachiko; Burger, Paul R; Garfin, Timothy; George, Richard G; Culleton, Brendan J; Kennett, Douglas J

    2016-01-01

    Archaeological sediments from mounds within the mangrove zone of far-southern Pacific coastal Chiapas, Mexico, are characterized in order to test the hypothesis that specialized pyro-technological activities of the region's prehistoric inhabitants (salt and ceramic production) created the accumulations visible today. Fourier transform infrared spectroscopy (FT-IR) is used to characterize sediment mineralogy, while portable X-ray fluorescence (pXRF) is used to determine elemental concentrations. Elemental characterization of natural sediments by both instrumental neutron activation analysis (INAA) and pXRF also contribute to understanding of processes that created the archaeological deposits. Radiocarbon dates combined with typological analysis of ceramics indicate that pyro-industrial activity in the mangrove zone peaked during the Late Formative and Terminal Formative periods, when population and monumental activity on the coastal plain and piedmont were also at their peaks. © The Author(s) 2015.

  4. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from WEATHERBIRD II in the Coastal Waters of Florida and Gulf of Mexico from 2008-08-11 to 2011-06-30 (NCEI Accession 0144622)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144622 includes Surface underway data collected from WEATHERBIRD II in the Coastal Waters of Florida and Gulf of Mexico from 2008-08-11 to...

  5. Spatial and temporal structure of fish assemblages in a hyperhaline coastal system: Ría Lagartos, Mexico

    Directory of Open Access Journals (Sweden)

    Miguel Angel Peralta-Meixueiro

    2011-01-01

    Full Text Available The spatial and temporal fish species assemblages were analyzed throughout two annual cycles (2004-2005 and 2007-2008 in the Ría Lagartos Lagoon system, Mexico, via non-parametric multivariate analyses. We compared density and biomass of fish species among five habitat types defined by combinations of structure and environmental characteristics (hyperhaline, rocky, seagrass, channel, and marine, and three climatic seasons (dry, rainy, and northerlies. A total of 11,187 individuals distributed in 32 families and 63 species were collected. The most numerically abundant species were Floridichthys polyommus and Cyprinodon artifrons, while Sphoeroides testudineus contributed to the greatest biomass. Species composition consisted mainly of estuarine and euryhaline marine species. Spatially, a saline gradient was observed with marine conditions in the mouth, and increasing to over 100 in the inner zone of the system. Species richness, diversity and biomass declined from the mouth to the inner zone, while density showed an inverse tendency, with the highest values in the inner zone. Thus the salinity was the variable that best explained the spatial fish assemblages" structure. The ichthyofauna composition did not change over time, but the dominant species varied with the years. The abundance of juvenile specimens, suggest that the different habitats are used as feeding and breeding zones; hence it is proposed that protection strategies be pursued not only for the lagoon system but also for the northern zone of the Yucatan Peninsula.Los ensamblajes espacio temporales de peces fueron analizados a través de dos ciclos anuales (2004-2005 y 2007-2008 en el sistema lagunar Ría Lagartos, México, vía análisis multivariados no paramétricos. Se comparó la densidad y biomasa de peces entre los cinco tipos de hábitats definidos por la combinación de características estructurales y ambientales (hiperhalino, rocoso, pastos, canal y marino y tres temporadas

  6. 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).

  7. 78 FR 69664 - Proposed Information Collection Request; Comment Request; Approval of State Coastal Nonpoint...

    Science.gov (United States)

    2013-11-20

    ... Collection Request; Comment Request; Approval of State Coastal Nonpoint Pollution Control Programs AGENCY... to submit an information collection request (ICR), ``Approval of State Coastal Nonpoint Pollution... Watershed Protection Division, Office of Wetlands Oceans and Watersheds, Mail Code 4503-T, Environmental...

  8. "Wetlands: Water Living Filters?",

    OpenAIRE

    Dordio, Ana; Palace, A. J.; Pinto, Ana Paula

    2008-01-01

    Human societies have indirectly used natural wetlands as wastewater discharge sites for many centuries. Observations of the wastewater depuration capacity of natural wetlands have led to a greater understanding of the potential of these ecosystems for pollutant assimilation and have stimulated the development of artificial wetlands systems for treatment of wastewaters from a variety of sources. Constructed wetlands, in contrast to natural wetlands, are human-made systems that are designed, bu...

  9. Gulf of Mexico Regional Collaborative Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Judd, Kathleen S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Judd, Chaeli [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Engel-Cox, Jill A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gulbransen, Thomas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Anderson, Michael G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Woodruff, Dana L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thom, Ronald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Guzy, Michael [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hardin, Danny [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Estes, Maury [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2007-12-01

    cover change at five other bays in the Gulf of Mexico to demonstrate extensibility of the analytical tools; and Initiated development of a conceptual model for understanding the causes and effects of HABs in the Gulf of Mexico IT Tool Development; Established a website with the GoMRC web-based tools at www.gomrc.org; Completed development of an ArcGIS-based decision support tool for SAV restoration prioritization decisions, and demonstrated its use in Mobile Bay; Developed a web-based application, called Conceptual Model Explorer (CME), that enables non-GIS users to employ the prioritization model for SAV restoration; Created CME tool enabling scientists to view existing, and create new, ecosystem conceptual models which can be used to document cause-effect relationships within coastal ecosystems, and offer guidance on management solutions; Adapted the science-driven advanced web search engine, Noesis, to focus on an initial set of coastal and marine resource issues, including SAV and HABs; Incorporated map visualization tools with initial data layers related to coastal wetlands and SAVs; and Supported development of a SERVIR portal for data management and visualization in the southern Gulf of Mexico, as well as training of end users in Mexican Gulf States.

  10. Land Use in Korean Tidal Wetlands: Impacts and Management Strategies

    Science.gov (United States)

    Hong, Sun-Kee; Koh, Chul-Hwan; Harris, Richard R.; Kim, Jae-Eun; Lee, Jeom-Sook; Ihm, Byung-Sun

    2010-05-01

    The coastal landscapes in southwestern Korea include a diverse array of tidal wetlands and salt marshes. These coastal zones link the ecological functions of marine tidal wetlands and freshwater ecosystems with terrestrial ecosystems. They are rich in biological diversity and play important roles in sustaining ecological health and processing environmental pollutants. Korean tidal wetlands are particularly important as nurseries for economically important fishes and habitats for migratory birds. Diking, draining, tourism, and conversion to agricultural and urban uses have adversely affected Korean tidal wetlands. Recent large development projects have contributed to further losses. Environmental impact assessments conducted for projects affecting tidal wetlands and their surrounding landscapes should be customized for application to these special settings. Adequate environmental impact assessments will include classification of hydrogeomorphic units and consideration of their responses to biological and environmental stressors. As is true worldwide, Korean laws and regulations are changing to be more favorable to the conservation and protection of tidal wetlands. More public education needs to be done at the local level to build support for tidal wetland conservation. Some key public education points include the role of tidal wetlands in maintaining healthy fish populations and reducing impacts of nonpoint source pollution. There is also a need to develop procedures for integrating economic and environmental objectives within the overall context of sustainable management and land uses.

  11. Across Hydrological Interfaces from Coastal Watersheds to the Open Lake: Finding Landscape Signals in the Great Lakes Coastal Zone

    Science.gov (United States)

    Over the past decade, our group has been working to bring coastal ecosystems into integrated basin-lakewide monitoring and assessment strategies for the Great Lakes. We have conducted a wide range of research on coastal tributaries, coastal wetlands, semi-enclosed embayments an...

  12. Gulf-Wide Information System, Environmental Sensitivity Index Scrub-Shrub and Wetlands, Geographic NAD83, LDWF (2001) [esi_scrub-shrub_wetland_LDWF_2001

    Data.gov (United States)

    Louisiana Geographic Information Center — This data set contains Environmental Sensitivity Index (ESI) scrub-shrub and wetlands data of coastal Louisiana. The ESI is a classification and ranking system,...

  13. Growth, mortality and migratory pattern of white shrimp (Litopenaeus vannamei, Crustacea, Penaeidae in the Carretas-Pereyra coastal lagoon system, Mexico

    Directory of Open Access Journals (Sweden)

    G Rivera-Velázquez

    2008-06-01

    Full Text Available The growth, mortality and migration pattern of the population of Litopenaeus vannamei Boone 1931 in the Carretas-Pereyra coastal lagoon system, Mexico, were studied. The shrimp spatial distribution and abundance were analyzed in relation to salinity, water temperature, and substrate. A total of 2 669 shrimps was collected at 22 sites sampled monthly from March 2004 to August 2005. Juvenile shrimps of L. vannamei were present in the coastal lagoon system throughout the year, reaching densities from 0.001 to 0.302 ind/m². The estimated daily growth rate was 0.06 to 0.27 mm carapace length (CL. No significant seasonal differences were appreciated. Weekly total mortality (Z was between 0.04 and 0.34. Recruits, juveniles and sub-adults displayed a bimodal distributional pattern regulated by the prevailing conditions during the dry season. The peak abundance of juvenile stages occurred in December-January and March-May. The abundance presented an inverse correlation with salinity (r=-0.42; pSe estudió el crecimiento, la mortalidad y el patrón de migración del camarón Litopenaeus vannamei Boone 1931 en el sistema lagunar costero Carretas Pereyra, México. La distribución espacial y la abundancia fueron analizadas con relación a la salinidad, temperatura y substrato. De marzo de 2004 a agosto de 2005 se recolectó un total de 2669 camarones con un muestreo mensual en 22 sitios. Los jóvenes se hallaron todo el año en el sistema lagunar costero, con densidades entre 0.001 y 0.302 ind/m². La tasa de crecimiento diaria fue de 0.06 a 0.27 mm longitud del cefalotórax (CL y no se apreciaron diferencias significativas entre estaciones. La mortalidad total (Z semanal estuvo entre 0.04 y 0.34. Reclutas, jóvenes y subadultos presentan un patrón de distribución bimodal regulado por las condiciones prevalecientes durante la estación de estío. Los valores máximos de abundancia de los estadios juveniles se presentan en diciembre-enero y marzo-mayo. La

  14. Ohio Uses Wetlands Program Development Grants to Protect Wetlands

    Science.gov (United States)

    The wetland water quality standards require the use of ORAM score to determine wetland quality. OEPA has also used these tools to evaluate wetland mitigation projects, develop performance standards for wetland mitigation banks and In Lieu Fee programs an.

  15. Spatial configuration trends in coastal Louisiana from 1985 to 2010

    Science.gov (United States)

    Couvillion, Brady; Fischer, Michelle; Beck, Holly J.; Sleavin, William J.

    2016-01-01

    From 1932 to 2010, coastal Louisiana has experienced a net loss of 4877 km2 of wetlands. As the area of these wetlands has changed, so too has the spatial configuration of the landscape. The resulting landscape is a mosaic of patches of wetlands and open water. This study examined the spatial and temporal variability of trajectories of landscape configuration and the relation of those patterns to the trajectories of land change in wetlands during a 1985–2010 observation period. Spatial configuration was quantified using multi-temporal satellite imagery and an aggregation index (AI). The results of this analysis indicate that coastal Louisiana experienced a reduction in the AI of coastal wetlands of 1.07 %. In general, forested wetland and fresh marsh types displayed the highest aggregation and stability. The remaining marsh types, (intermediate, brackish, and saline) all experienced disaggregation during the time period, with increasing severity of disaggregation along an increasing salinity gradient. Finally, a correlation (r 2 = 0.5562) was found between AI and the land change rate for the subsequent period, indicating that fragmentation can increase the vulnerability of wetlands to further wetland loss. These results can help identify coastal areas which are susceptible to future wetland loss.

  16. Observation of Wetland Dynamics with Global Navigation Satellite Signals Reflectometry

    Science.gov (United States)

    Zuffada, C.; Shah, R.; Nghiem, S. V.; Cardellach, E.; Chew, C. C.

    2015-12-01

    Wetland dynamics is crucial to changes in both atmospheric methane and terrestrial water storage. The Intergovernmental Panel on Climate Change's Fifth Assessment Report (IPCC AR5) highlights the role of wetlands as a key driver of methane (CH4) emission, which is more than one order of magnitude stronger than carbon dioxide as a greenhouse gas in the centennial time scale. Among the multitude of methane emission sources (hydrates, livestock, rice cultivation, freshwaters, landfills and waste, fossil fuels, biomass burning, termites, geological sources, and soil oxidation), wetlands constitute the largest contributor with the widest uncertainty range of 177-284 Tg(CH4) yr-1 according to the IPCC estimate. Wetlands are highly susceptible to climate change that might lead to wetland collapse. Such wetland destruction would decrease the terrestrial water storage capacity and thus contribute to sea level rise, consequently exacerbating coastal flooding problems. For both methane change and water storage change, wetland dynamics is a crucial factor with the largest uncertainty. Nevertheless, a complete and consistent map of global wetlands still needs to be obtained as the Ramsar Convention calls for a wetlands inventory and impact assessment. We develop a new method for observations of wetland change using Global Navigation Satellite Signals Reflectometry (GNSS-R) signatures for global wetland mapping in synergy with the existing capability, not only as a static inventory but also as a temporal dataset, to advance the capability for monitoring the dynamics of wetland extent relevant to addressing the science issues of CH4 emission change and terrestrial water storage change. We will demonstrate the capability of the new GNSS-R method over a rice field in the Ebro Delta wetland in Spain.

  17. Wonderful Wetlands: An Environmental Education Curriculum Guide for Wetlands.

    Science.gov (United States)

    King County Parks Div., Redmond, WA.

    This curriculum guide was designed to give teachers, students, and society a better understanding of wetlands in the hope that they learn why wetlands should be valued and preserved. It explores what is meant by wetlands, functions and values of wetlands, wetland activities, and wetland offerings which benefit animal and plant life, recreation,…

  18. Coastal land loss and hypoxia: the 'outwelling' hypothesis revisited

    International Nuclear Information System (INIS)

    Das, Anindita; Justic, Dubravko; Swenson, Erick; Turner, R Eugene; Inoue, Masamichi; Park, Dongho

    2011-01-01

    It is generally believed that interannual variability in the areal extent of the Gulf of Mexico hypoxia is driven primarily by the magnitude of the Mississippi River freshwater and nutrient fluxes. It has recently been proposed that outwelling of carbon from deteriorating coastal wetlands into the surrounding Gulf of Mexico could be an important mechanism promoting the development of hypoxia. We used a coupled hydrology-hydrodynamics model of the Barataria estuary, a site of massive wetland loss, to calculate the fluxes of nitrogen, chlorophyll a and carbon at the estuary-ocean interface. The hydrology model calculates runoff from rainfall and evaporation data, and then feeds it into the high-resolution (100 m x 100 m grid, 1.3 million elements), two-dimensional depth-integrated hydrodynamic model. Model results show substantial outwelling of total organic carbon (TOC, 110 x 10 6 kg yr -1 ), dissolved organic carbon (DOC, 94.3 x 10 6 kg yr -1 ), particulate organic carbon (POC, 15.7 x 10 6 kg yr -1 ) and chlorophyll a (Chl a, 0.3 x 10 6 kg yr -1 ) from the estuary to the coastal waters and an import of nitrate (N-NO 3 , 6.9 x 10 6 kg yr -1 ) from the nutrient-rich coastal waters into the estuary. Estuarine fluxes of TOC, DOC, POC, Chl a and N-NO 3 , account for 2.8%, 2.7%, 3.4%, 7.5% and 1%, respectively, of the annual fluxes carried by the lower Mississippi River. The flux of total nitrogen was not statistically significant. Overall, this study supports the conclusion of the previous modeling study (Das et al 2010 Ecol. Modeling 221 978-85), suggesting that the Barataria estuary supplies a relatively small amount of the carbon consumed in the Gulf's hypoxic zone. Importantly, our results indicate that import of nitrate from the coastal waters and its assimilation within the estuary could account for 38% and 208%, respectively, of the calculated TOC and Chl a exports, demonstrating the pervasive control of the Mississippi River on the productivity of this shelf.

  19. Defining restoration targets for water depth and salinity in wind-dominated Spartina patens (Ait.) Muhl. coastal marshes

    Science.gov (United States)

    Nyman, J.A.; LaPeyre, Megan K.; Caldwell, Andral W.; Piazza, Sarai C.; Thom, C.; Winslow, C.

    2009-01-01

    Coastal wetlands provide valued ecosystem functions but the sustainability of those functions often is threatened by artificial hydrologic conditions. It is widely recognized that increased flooding and salinity can stress emergent plants, but there are few measurements to guide restoration, management, and mitigation. Marsh flooding can be estimated over large areas with few data where winds have little effect on water levels, but quantifying flooding requires hourly measurements over long time periods where tides are wind-dominated such as the northern Gulf of Mexico. Estimating salinity of flood water requires direct daily measurements because coastal marshes are characterized by dynamic salinity gradients. We analyzed 399,772 hourly observations of water depth and 521,561 hourly observations of water salinity from 14 sites in Louisiana coastal marshes dominated by Spartina patens (Ait.) Muhl. Unlike predicted water levels, observed water levels varied monthly and annually. We attributed those observed variations to variations in river runoff and winds. In stable marshes with slow wetland loss rates, we found that marsh elevation averaged 1 cm above mean high water, 15 cm above mean water, and 32 cm above mean low water levels. Water salinity averaged 3.7 ppt during April, May, and June, and 5.4 ppt during July, August, and September. The daily, seasonal, and annual variation in water levels and salinity that were evident would support the contention that such variation be retained when designing and operating coastal wetland management and restoration projects. Our findings might be of interest to scientists, engineers, and managers involved in restoration, management, and restoration in other regions where S. patens or similar species are common but local data are unavailable.

  20. Relating groundwater to seasonal wetlands in southeastern Wisconsin, USA

    Science.gov (United States)

    Skalbeck, J.D.; Reed, D.M.; Hunt, R.J.; Lambert, J.D.

    2009-01-01

    Historically, drier types of wetlands have been difficult to characterize and are not well researched. Nonetheless, they are considered to reflect the precipitation history with little, if any, regard for possible relation to groundwater. Two seasonal coastal wetland types (wet prairie, sedge meadow) were investigated during three growing seasons at three sites in the Lake Michigan Basin, Wisconsin, USA. The six seasonal wetlands were characterized using standard soil and vegetation techniques and groundwater measurements from the shallow and deep systems. They all met wetland hydrology criteria (e.g., water within 30 cm of land surface for 5% of the growing season) during the early portion of the growing season despite the lack of appreciable regional groundwater discharge into the wetland root zones. Although root-zone duration analyses did not fit a lognormal distribution previously noted in groundwater-dominated wetlands, they were able to discriminate between the plant communities and showed that wet prairie communities had shorter durations of continuous soil saturation than sedge meadow communities. These results demonstrate that the relative rates of groundwater outflows can be important for wetland hydrology and resulting wetland type. Thus, regional stresses to the shallow groundwater system such as pumping or low Great Lake levels can be expected to affect even drier wetland types. ?? Springer-Verlag 2008.

  1. Wetlands in a changing climate: Science, policy and management

    Science.gov (United States)

    Moomaw, William R.; Chmura, G.L.; Davies, Gillian T.; Finlayson, Max; Middleton, Beth A.; Natali, Sue M.; Perry, James; Roulet, Nigel; Sutton-Grier, Ariana

    2018-01-01

    Part 1 of this review synthesizes recent research on status and climate vulnerability of freshwater and saltwater wetlands, and their contribution to addressing climate change (carbon cycle, adaptation, resilience). Peatlands and vegetated coastal wetlands are among the most carbon rich sinks on the planet sequestering approximately as much carbon as do global forest ecosystems. Estimates of the consequences of rising temperature on current wetland carbon storage and future carbon sequestration potential are summarized. We also demonstrate the need to prevent drying of wetlands and thawing of permafrost by disturbances and rising temperatures to protect wetland carbon stores and climate adaptation/resiliency ecosystem services. Preventing further wetland loss is found to be important in limiting future emissions to meet climate goals, but is seldom considered. In Part 2, the paper explores the policy and management realm from international to national, subnational and local levels to identify strategies and policies reflecting an integrated understanding of both wetland and climate change science. Specific recommendations are made to capture synergies between wetlands and carbon cycle management, adaptation and resiliency to further enable researchers, policy makers and practitioners to protect wetland carbon and climate adaptation/resiliency ecosystem services.

  2. Climate change: Potential impacts and interactions in wetlands of the United States

    Science.gov (United States)

    Burkett, Virginia; Kusler, Jon

    2000-01-01

    Wetlands exist in a transition zone between aquatic and terrestrial environments which can be altered by subtle changes in hydrology. Twentieth century climate records show that the United States is generally experiencing a trend towards a wetter, warmer climate; some climate models suggest that his trend will continue and possibly intensify over the next 100 years. Wetlands that are most likely to be affected by these and other potential changes (e.g., sea-level rise) associated with atmospheric carbon enrichment include permafrost wetlands, coastal and estuarine wetlands, peatlands, alpine wetlands, and prairie pothote wetlands. Potential impacts range from changes in community structure to changes in ecological function, and from extirpation to enhancement. Wetlands (particularly boreal peatlands) play an important role in the global carbon cycle, generally sequestering carbon in the form of biomass, methane, dissolved organic material and organic sediment. Wetlands that are drained or partially dried can become a net source of methane and carbon dioxide to the atmosphere, serving as a positive biotic feedback to global warming. Policy options for minimizing the adverse impacts of climate change on wetland ecosystems include the reduction of current anthropogenic stresses, allowing for inland migration of coastal wetlands as sea-level rises, active management to preserve wetland hydrology, and a wide range of other management and restoration options.

  3. Evaluating Satellite and Supercomputing Technologies for Improved Coastal Ecosystem Assessments

    Science.gov (United States)

    McCarthy, Matthew James

    Water quality and wetlands represent two vital elements of a healthy coastal ecosystem. Both experienced substantial declines in the U.S. during the 20th century. Overall coastal wetland cover decreased over 50% in the 20th century due to coastal development and water pollution. Management and legislative efforts have successfully addressed some of the problems and threats, but recent research indicates that the diffuse impacts of climate change and non-point source pollution may be the primary drivers of current and future water-quality and wetland stress. In order to respond to these pervasive threats, traditional management approaches need to adopt modern technological tools for more synoptic, frequent and fine-scale monitoring and assessment. In this dissertation, I explored some of the applications possible with new, commercial satellite imagery to better assess the status of coastal ecosystems. Large-scale land-cover change influences the quality of adjacent coastal water. Satellite imagery has been used to derive land-cover maps since the 1960's. It provides multiple data points with which to evaluate the effects of land-cover change on water quality. The objective of the first chapter of this research was to determine how 40 years of land-cover change in the Tampa Bay watershed (6,500 km2) may have affected turbidity and chlorophyll concentration - two proxies for coastal water quality. Land cover classes were evaluated along with precipitation and wind stress as explanatory variables. Results varied between analyses for the entire estuary and those of segments within the bay. Changes in developed land percent cover best explained the turbidity and chlorophyll-concentration time series for the entire bay (R2 > 0.75, p Ocean-color satellite imagery was used to derive proxies for coastal water with near-daily satellite observations since 2000. The goal of chapter two was to identify drivers of turbidity variability for 11 National Estuary Program water bodies

  4. Why are wetlands important?

    Science.gov (United States)

    Wetlands are among the most productive ecosystems in the world, comparable to rain forests and coral reefs. An immense variety of species of microbes, plants, insects, amphibians, reptiles, birds, fish, and mammals can be part of a wetland ecosystem.

  5. Percent Wetland Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — Wetlands act as filters, removing or diminishing the amount of pollutants that enter surface water. Higher values for percent of wetland cover (WETLNDSPCT) may be...

  6. Percent Wetland Cover (Future)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Wetlands act as filters, removing or diminishing the amount of pollutants that enter surface water. Higher values for percent of wetland cover (WETLNDSPCT) may be...

  7. VSWI Wetlands Advisory Layer

    Data.gov (United States)

    Vermont Center for Geographic Information — This dataset represents the DEC Wetlands Program's Advisory layer. This layer makes the most up-to-date, non-jurisdictional, wetlands mapping avaiable to the public...

  8. Using Coupled Models to Study the Effects of River Discharge on Biogeochemical Cycling and Hypoxia in the Northern Gulf of Mexico

    Science.gov (United States)

    Penta, Bradley; Ko, D.; Gould, Richard W.; Arnone, Robert A.; Greene, R.; Lehrter, J.; Hagy, James; Schaeffer, B.; Murrell, M.; Kurtz, J.; hide

    2009-01-01

    We describe emerging capabilities to understand physical processes and biogeoehemical cycles in coastal waters through the use of satellites, numerical models, and ship observations. Emerging capabilities provide significantly improved ability to model ecological systems and the impact of environmental management actions on them. The complex interaction of physical and biogeoehemical processes responsible for hypoxic events requires an integrated approach to research, monitoring, and modeling in order to fully define the processes leading to hypoxia. Our efforts characterizes the carbon cycle associated with river plumes and the export of organic matter and nutrients form coastal Louisiana wetlands and embayments in a spatially and temporally intensive manner previously not possible. Riverine nutrients clearly affect ecosystems in the northern Gulf of Mexico as evidenced in the occurrence of regional hypoxia events. Less known and largely unqualified is the export of organic matter and nutrients from the large areas of disappearing coastal wetlands and large embayments adjacent to the Louisiana Continental Shelf. This project provides new methods to track the river plume along the shelf and to estimate the rate of export of suspended inorganic and organic paniculate matter and dissolved organic matter form coastal habitats of south Louisiana.

  9. Rehabilitation of coastal wetlands of India

    Digital Repository Service at National Institute of Oceanography (India)

    Untawale, A.G.

    stream_size 16 stream_content_type text/plain stream_name Ecosyst_Rehabilitation_1992_2_333.pdf.txt stream_source_info Ecosyst_Rehabilitation_1992_2_333.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

  10. Towards a macrosystems approach for successful coastal management

    Science.gov (United States)

    Managing coastal resources for resiliency and sustainability often requires integrative, multi-disciplinary approaches across varying spatial and temporal scales to engage stakeholders and inform decision-makers. We discuss case studies integrating wetland ecology, economics, soc...

  11. How a clogged canal impacts ecological health in a tropical urban wetland ecosystem

    Science.gov (United States)

    The coastal city of San Juan, Puerto Rico is a tropical urban ecosystem interwoven among a series of interconnected bays, lagoons, canals, and mangrove wetlands. As the city has expanded, infilling and urban encroachment on what was previously mangrove wetland and open estuarine ...

  12. How a clogged canal effects ecological and human health in a tropical urban wetland ecosystem

    Science.gov (United States)

    The coastal city of San Juan, Puerto Rico is a tropical urban ecosystem interwoven among a series of interconnected bays, lagoons, canals, and mangrove wetlands. As the city has expanded, infilling and urban encroachment on what was previously mangrove wetland and open estuarine ...

  13. Submerged Aquatic Vegetation observations from Coastal Alabama, Gulf of Mexico from 2015-05-01 to 2016-06-21 (NCEI Accession 0161265)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of GIS data documenting the location, species composition, and other habitat characteristics of submerged aquatic vegetation (SAV) in coastal...

  14. Historical Submerged Aquatic Vegetation (SAV) Distributions from Coastal Alabama, Gulf of Mexico from 1940-01-01 to 1966-10-21 (NCEI Accession 0162477)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Historic black and white aerial photographs of coastal Alabama (Mobile Bay and adjacent waters) from 1940, 1955, and 1966 were digitized and georeferenced using Blue...

  15. IMPACTS OF WETLAND DEGRADATION IN NIGER DELTA NIGERIA AND ITS SIGNIFICANCE IN FLOOD CONTROL

    Directory of Open Access Journals (Sweden)

    Enwere Chidimma Loveline

    2015-08-01

    Full Text Available  Wetlands perform a wide variety of functions that include flood control, ground water recharge, shore line stabilization, storm protection and climate moderation. However, despite these huge wetland functions, it has witnessed poor appreciation and dreadful conditions. Niger Delta has witnessed constant coastal erosion and rising sea level, this has led to large portions of the landmass being eroded. This paper aims to review some environmental effects of flooding in the Niger Delta region of Nigeria to provide the desired knowledge of role that wetlands play in reducing flood impacts. However, having witnessed the flood, the experience opened my eyes to the environmental challenges facing Niger Delta with respect to Wetlands degradation, poor perception of wetland values and functions, poor environmental practices and non-implementation of environmental regulations. This memorable experience rekindled the desire and motivation to seek a solution to wetland degradation with the aim of recognizing significance of wetlands at the centre of achieving both livelihood and biodiversity improvements to address coastal flooding problem.The study therefore concludes that wetlands are very significant in flood control and thus the conservation and restoration of wetlands, should put in place measures to reduce wetland destruction.International Journal of EnvironmentVolume-4, Issue-3, June-August 2015Page: 177-184

  16. New Orleans, Louisiana Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions in the Gulf of Mexico....

  17. Monitoring man's impact in the coastal zone

    International Nuclear Information System (INIS)

    Benton, A.R. Jr.; Snell, W.W.

    1979-01-01

    The paper examines the monitoring of man's impact in the coastal zone. Color infrared photography shows destroyed or degraded wetlands or beaches, and makes possible relevant linear or aerial measurements with aerial photography. It can also categorize the environmental impacts which have accrued as the result of completion of water development projects. Aerial photography of the Texas coastal zone illustrates the nature and degree of damage likely to occur as a result of construction or maintenance projects. It is concluded that the method of assigning realistic values to unit areas of wetlands and beaches will make it feasible to incorporate the cost of estuarine damages into the cost estimates of water development schemes

  18. Freshwater Wetlands: A Citizen's Primer.

    Science.gov (United States)

    Catskill Center for Conservation and Development, Inc., Hobart, NY.

    The purpose of this "primer" for the general public is to describe the general characteristics of wetlands and how wetland alteration adversely affects the well-being of humans. Particular emphasis is placed on wetlands in New York State and the northeast. Topics discussed include wetland values, destruction of wetlands, the costs of…

  19. Patterns and drivers for wetland connections in the Prairie Pothole Region, United States

    Science.gov (United States)

    Vanderhoof, Melanie; Christensen, Jay R.; Alexander, Laurie C.

    2017-01-01

    Ecosystem function in rivers, lakes and coastal waters depends on the functioning of upstream aquatic ecosystems, necessitating an improved understanding of watershed-scale interactions including variable surface-water flows between wetlands and streams. As surface water in the Prairie Pothole Region expands in wet years, surface-water connections occur between many depressional wetlands and streams. Minimal research has explored the spatial patterns and drivers for the abundance of these connections, despite their potential to inform resource management and regulatory programs including the U.S. Clean Water Act. In this study, wetlands were identified that did not intersect the stream network, but were shown with Landsat images (1990–2011) to become merged with the stream network as surface water expanded. Wetlands were found to spill into or consolidate with other wetlands within both small (2–10 wetlands) and large (>100 wetlands) wetland clusters, eventually intersecting a stream channel, most often via a riparian wetland. These surface-water connections occurred over a wide range of wetland distances from streams (averaging 90–1400 m in different ecoregions). Differences in the spatial abundance of wetlands that show a variable surface-water connection to a stream were best explained by smaller wetland-to-wetland distances, greater wetland abundance, and maximum surface-water extent. This analysis demonstrated that wetland arrangement and surface water expansion are important mechanisms for depressional wetlands to connect to streams and provides a first step to understanding the frequency and abundance of these surface-water connections across the Prairie Pothole Region.

  20. Application of the coastal generalized ecosystem model (CGEM) to assess the impacts of a potential future climate scenario on northern Gulf of Mexico hypoxia

    Science.gov (United States)

    Mechanistic hypoxia models for the northern Gulf of Mexico are being used to guide policy goals for Mississippi River nutrient loading reductions. However, to date, these models have not examined the effects of both nutrient loads and future climate. Here, we simulate a future c...