Coastal ecosystems, productivity and ecosystem protection: Coastal ecosystem management

International Nuclear Information System (INIS)

Ngoile, M.A.K.; Horrill, C.J.

1993-01-01

The coastal zone is a complex ecosystem under the influence of physical, chemical and biological processes. Under natural conditions these processes interact and maintain an equilibrium in the coastal ecosystem. Man makes a variety of important uses of coastal resources, ranging from harvesting of living resources, extraction of nonliving resources, and recreation, to the disposal of wastes. Man's extensive use of the oceans introduces factors which bring about an imbalance in the natural processes, and may result in harmful and hazardous effects to life hindering further use. Man's pressure on the resources of the coastal zone is already manifest and will increase manifold. This calls for an immediate solution to the protection and sustainable use of coastal resources. The current sectorized approach to the management of human activities will not solve the problem because the different resources of the coastal zone interact in such a manner that disturbances in one cause imbalance in the others. This is further complicated by the sectorized approach to research and limited communication between policy makers, managers, and scientists. This paper discusses strategies for managing coastal-resources use through an integrated approach. The coastal zone is presented as a unified ecosystem in equilibrium and shows that man's extensive use of the coastal resources destabilizes this equilibrium. Examples from the East Africa Region are presented. 15 refs, 2 figs, 3 tabs

Coastal upwelling in the Gelendzhik area of the Black Sea: Effect of wind and dynamics

Science.gov (United States)

Silvestrova, K. P.; Zatsepin, A. G.; Myslenkov, S. A.

2017-07-01

Long series data of a thermistor chain in the Black Sea coastal zone near Gelendzhik were analyzed. A thermistor chain installed 1 km offshore and at a depth of 22 m. There are full and incomplete upwelling events observed. The study of upwelling genesis based on: wind speed data from the NCEP/CFSR reanalysis and Gelendzhik weather station, velocity and direction of coastal currents measured by ADCP profiler moored on the bottom near the thermistor chain. Over the whole observation period (warm seasons of 2013-2015), more than 40 events of upwelling were registered four of them were full upwellings, when presence of under-thermocline water was observed near the sea surface. For every upwelling event, conditions prior to the changes in thermic structure, were analyzed. It is found that full upwelling generally occur under synergistic wind and current forcing. Fairly strong forcing of one of these factors is sufficient for partial upwelling to occur.

Combined impact of ocean acidification and corrosive waters in a river-influenced coastal upwelling area off Central Chile

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Vargas, C.; De La Hoz, M.; San Martin, V.; Contreras, P.; Navarro, J. M.; Lagos, N. A.; Lardies, M.; Manríquez, P. H.; Torres, R.

2012-12-01

Elevated CO2 in the atmosphere promotes a cascade of physical and chemical changes affecting all levels of biological organization, and the evidence from local to global scales has shown that such anthropogenic climate change has triggered significant responses in the Earth's biota. The increased concentration of CO2 is likely to cause a corresponding increase in ocean acidification (OA). In addition, economically valuable shellfish species predominantly inhabit coastal regions both in natural stocks and/or in managed stocks and farming areas. Many coastal ecosystems may experience seawater pCO2 levels significantly higher than expected from equilibrium with the atmosphere, which in this case are strongly linked to biological processes and/or the impact of two important processes; river plumes and coastal upwelling events, which indeed interplay in a very dynamic way on continental shelves, resulting in both source or sink of CO2 to the atmosphere. Coastal ecosystems receive persistent acid inputs as a result of freshwater discharges from river basins into the coastal domain. In this context, since shellfish resources and shellfish aquaculture activities predominantly occur in nearshore areas, it is expected that shellfish species inhabiting river-influenced benthic ecosystems will be exposed persistently to acidic conditions that are suboptimal for its development. In a wider ecological context, little is also known about the potential impacts of acid waters on the performance of larvae and juveniles of almost all the marine species inhabiting this benthic ecosystem in Eastern Southern Pacific Ocean. We present here the main results of a research study aimed to investigate the environmental conditions to which economically valuable calcifiers shellfish species are exposed in a river-influenced continental shelf off Central Chile. By using isotopic measurements in the dissolved inorganic carbon (DIC) pool (d13C-DIC) we showed the effect of the remineralization of

Seasonal and annual variability of coastal sulphur plumes in the northern Benguela upwelling system.

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Thomas Ohde

Full Text Available We investigated the seasonal and annual variability of surface sulphur plumes in the northern Benguela upwelling system off Namibia because of their significant impacts on the marine ecosystem, fishing industry, aquaculture farming and tourism due to their toxic properties. We identified the sulphur plumes in ocean colour satellite data of the medium resolution imaging spectrometer (MERIS for the 2002-2012 time period using the differences in the spectral properties of Namibian Benguela optical water types. The sulphur events have a strong seasonal cycle with pronounced main and off-seasons forced by local and remote-driven processes. The main peak season is in late austral summer and early austral autumn at the beginning of the annual upwelling cycle caused by increasing equatorwards alongshore winds. The sulphur plume activity is high between February and April during the seasonal oxygen minimum associated with the seasonal reduction of cross-shore ventilation of the bottom waters, the seasonal southernmost position of the Angola Benguela Frontal Zone, the seasonal maximum of water mass fractions of South Atlantic and Angola Gyre Central Waters as well as the seasonal arrival of the downwelling coastal trapped waves. The off-season is in austral spring and early austral summer during increased upwelling intensity and enhanced oxygen supply. The annual variability of sulphur events is characterized by very high activities in years 2004, 2005 and 2010 interrupted by periods of lower activity in years 2002 to 2003, 2006 to 2009 and 2011 to 2012. This result can be explained by the relative contributions or adding effects of local and remote-driven forces (from the equatorial area. The probability for the occurrence of sulphur plumes is enhanced in years with a lower annual mean of upwelling intensity, decreased oxygen supply associated with decreased lateral ventilation of bottom waters, more southern position of the Angola Benguela Frontal Zone

Seasonal and annual variability of coastal sulphur plumes in the northern Benguela upwelling system.

Science.gov (United States)

Ohde, Thomas; Dadou, Isabelle

2018-01-01

We investigated the seasonal and annual variability of surface sulphur plumes in the northern Benguela upwelling system off Namibia because of their significant impacts on the marine ecosystem, fishing industry, aquaculture farming and tourism due to their toxic properties. We identified the sulphur plumes in ocean colour satellite data of the medium resolution imaging spectrometer (MERIS) for the 2002-2012 time period using the differences in the spectral properties of Namibian Benguela optical water types. The sulphur events have a strong seasonal cycle with pronounced main and off-seasons forced by local and remote-driven processes. The main peak season is in late austral summer and early austral autumn at the beginning of the annual upwelling cycle caused by increasing equatorwards alongshore winds. The sulphur plume activity is high between February and April during the seasonal oxygen minimum associated with the seasonal reduction of cross-shore ventilation of the bottom waters, the seasonal southernmost position of the Angola Benguela Frontal Zone, the seasonal maximum of water mass fractions of South Atlantic and Angola Gyre Central Waters as well as the seasonal arrival of the downwelling coastal trapped waves. The off-season is in austral spring and early austral summer during increased upwelling intensity and enhanced oxygen supply. The annual variability of sulphur events is characterized by very high activities in years 2004, 2005 and 2010 interrupted by periods of lower activity in years 2002 to 2003, 2006 to 2009 and 2011 to 2012. This result can be explained by the relative contributions or adding effects of local and remote-driven forces (from the equatorial area). The probability for the occurrence of sulphur plumes is enhanced in years with a lower annual mean of upwelling intensity, decreased oxygen supply associated with decreased lateral ventilation of bottom waters, more southern position of the Angola Benguela Frontal Zone, increased mass

Coastal upwelling linked to toxic Pseudo-nitzschia australis blooms in Los Angeles coastal waters, 2005-2007

KAUST Repository

Schnetzer, Astrid; Jones, Burton; Schaffner, Rebecca A.; Cetinić, Ivona; Fitzpatrick, Elizabeth; Miller, Peter E.; Seubert, Erica L.; Caron, David A.

2013-01-01

Harmful algal blooms dominated by the diatom Pseudo-nitzschia spp. have become a perennial but variable event within surface waters near the greater Los Angeles area. Toxic blooms during spring seasons from 2005 to 2007 varied strongly in their overall toxicity and duration. Differences in bloom dynamics were linked to differences in storm-induced river discharge following episodic rain events and coastal upwelling, both major coastal processes that led to the injection of nutrients into coastal surface waters. Heavy river runoff during early 2005, a record-rainfall year, favored a phytoplankton community mainly comprised of algal taxa other than Pseudo-nitzschia. The spring bloom during 2005 was associated with low domoic acid surface concentrations and minor contributions of (mainly) P. delicatissima to the diatom assemblage. In contrast, highly toxic P. australis-dominated blooms during spring seasons of 2006 and 2007 were linked to strong upwelling events. River discharge quotas in 2006 and 2007, in contrast to 2005, fell well below annual averages for the region. Surface toxin levels were linked to colder, more saline (i.e. upwelled) water over the 3-year study, but no such consistent relationship between domoic acid levels and other physiochemical parameters, such as macronutrient concentrations or nutrient ratios, was observed. © The Author 2013. Published by Oxford University Press. All rights reserved.

Coastal upwelling linked to toxic Pseudo-nitzschia australis blooms in Los Angeles coastal waters, 2005-2007

KAUST Repository

Schnetzer, Astrid

2013-06-10

Harmful algal blooms dominated by the diatom Pseudo-nitzschia spp. have become a perennial but variable event within surface waters near the greater Los Angeles area. Toxic blooms during spring seasons from 2005 to 2007 varied strongly in their overall toxicity and duration. Differences in bloom dynamics were linked to differences in storm-induced river discharge following episodic rain events and coastal upwelling, both major coastal processes that led to the injection of nutrients into coastal surface waters. Heavy river runoff during early 2005, a record-rainfall year, favored a phytoplankton community mainly comprised of algal taxa other than Pseudo-nitzschia. The spring bloom during 2005 was associated with low domoic acid surface concentrations and minor contributions of (mainly) P. delicatissima to the diatom assemblage. In contrast, highly toxic P. australis-dominated blooms during spring seasons of 2006 and 2007 were linked to strong upwelling events. River discharge quotas in 2006 and 2007, in contrast to 2005, fell well below annual averages for the region. Surface toxin levels were linked to colder, more saline (i.e. upwelled) water over the 3-year study, but no such consistent relationship between domoic acid levels and other physiochemical parameters, such as macronutrient concentrations or nutrient ratios, was observed. © The Author 2013. Published by Oxford University Press. All rights reserved.

Coastal upwelling fluxes of O2, N2O, and CO2 assessed from continuous atmospheric observations at Trinidad, California

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T. J. Lueker

2004-01-01

Full Text Available Continuous atmospheric records of O2/N2, CO2 and N2O obtained at Trinidad, California document the effects of air-sea exchange during coastal upwelling and plankton bloom events. The atmospheric records provide continuous observations of air-sea fluxes related to synoptic scale upwelling events over several upwelling seasons. Combined with satellite, buoy and local meteorology data, calculated anomalies in O2/N2 and N2O were utilized in a simple atmospheric transport model to compute air-sea fluxes during coastal upwelling. CO2 fluxes were linked to the oceanic component of the O2 fluxes through local hydrographic data and estimated as a function of upwelling intensity (surface ocean temperature and wind speed. Regional air-sea fluxes of O2/N2, N2O, and CO2 during coastal upwelling were estimated with the aid of satellite wind and SST data. Upwelling CO2 fluxes were found to represent ~10% of export production along the northwest coast of North America. Synoptic scale upwelling events impact the net exchange of atmospheric CO2 along the coastal margin, and will vary in response to the frequency and duration of alongshore winds that are subject to climate change.

Persistence of trophic hotspots and relation to human impacts within an upwelling marine ecosystem.

Science.gov (United States)

Santora, Jarrod A; Sydeman, William J; Schroeder, Isaac D; Field, John C; Miller, Rebecca R; Wells, Brian K

2017-03-01

Human impacts (e.g., fishing, pollution, and shipping) on pelagic ecosystems are increasing, causing concerns about stresses on marine food webs. Maintaining predator-prey relationships through protection of pelagic hotspots is crucial for conservation and management of living marine resources. Biotic components of pelagic, plankton-based, ecosystems exhibit high variability in abundance in time and space (i.e., extreme patchiness), requiring investigation of persistence of abundance across trophic levels to resolve trophic hotspots. Using a 26-yr record of indicators for primary production, secondary (zooplankton and larval fish), and tertiary (seabirds) consumers, we show distributions of trophic hotspots in the southern California Current Ecosystem result from interactions between a strong upwelling center and a productive retention zone with enhanced nutrients, which concentrate prey and predators across multiple trophic levels. Trophic hotspots also overlap with human impacts, including fisheries extraction of coastal pelagic and groundfish species, as well as intense commercial shipping traffic. Spatial overlap of trophic hotspots with fisheries and shipping increases vulnerability of the ecosystem to localized depletion of forage fish, ship strikes on marine mammals, and pollution. This study represents a critical step toward resolving pelagic areas of high conservation interest for planktonic ecosystems and may serve as a model for other ocean regions where ecosystem-based management and marine spatial planning of pelagic ecosystems is warranted. © 2016 by the Ecological Society of America.

Arabian Sea upwelling - A comparison between coastal and open ocean regions

Digital Repository Service at National Institute of Oceanography (India)

Muraleedharan, P.M.; PrasannaKumar, S.

The response of the eastern Arabian Sea to prevailing winds during an upwelling event, in the peak of southwest monsoon, was studied at both coastal and open ocean environment based on the data collected as a part of the Indian Joint Global Ocean...

Biogenic halocarbons from coastal oceanic upwelling regions as tropospheric halogen source

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Krüger, Kirstin; Fuhlbrügge, Steffen; Hepach, Helmke; Fiehn, Alina; Atlas, Elliot; Quack, Birgit

2016-04-01

Halogenated very short lived substances (VSLS) are naturally produced in the ocean and emitted to the atmosphere. Recently, oceanic upwelling regions in the tropical East Atlantic were identified as strong sources of brominated halocarbons to the troposphere. During a cruise of R/V METEOR in December 2012 the oceanic sources and emissions of various halogenated trace gases and their mixing ratios in the marine atmospheric boundary layer (MABL) were investigated above the Peruvian Upwelling for the first time. This study presents novel observations of the three VSLS bromoform, dibromomethane and methyl iodide together with high resolution meteorological measurements and Lagrangian transport modelling. Although relatively low oceanic emissions were observed, except for methyl iodide, surface atmospheric abundances were elevated. Radiosonde launches during the cruise revealed a low, stable MABL and a distinct trade inversion above acting both as strong barriers for convection and trace gas transport in this region. Significant correlations between observed atmospheric VSLS abundances, sea surface temperature, relative humidity and MABL height were found. We used a simple source-loss estimate to identify the contribution of oceanic emissions to observed atmospheric concentrations which revealed that the observed marine VSLS abundances were dominated by horizontal advection below the trade inversion. The observed VSLS variations can be explained by the low emissions and their accumulation under different MABL and trade inversion conditions. Finally, observations from a second Peruvian Upwelling cruise with R/V SONNE during El Nino in October 2015 will be compared to highlight the role of different El Nino Southern Oscillation conditions. This study confirms the importance of coastal oceanic upwelling and trade wind systems on creating effective transport barriers in the lowermost atmosphere controlling the distribution of VSLS abundances above coastal ocean upwelling

Phytoplankton community and environmental correlates in a coastal upwelling zone along western Taiwan Strait

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Wang, Yu; Kang, Jian-hua; Ye, You-yin; Lin, Geng-ming; Yang, Qing-liang; Lin, Mao

2016-02-01

Upwelling system in western Taiwan Strait is important for facilitating the fishery production. This study investigated hydro-chemical properties, phytoplankton biomass, phytoplankton species composition, three-dimensional (horizontal, vertical and transect) distribution of phytoplankton abundance, as well as phytoplankton annual variation and the correlation of phytoplankton community with the upwelling of underlying current and nutrients according to samples of Fujian-Guangdong coastal upwelling zone in western Taiwan Strait from August 27 to September 8, 2009. The results manifest that the nutrient-rich cold and high salinity current on the continental shelf of South China Sea upwells to the Fujian-Guangdong coastal waters through Taiwan Bank and the surging strength to surface is weak while strong at 30-m layer. The thermohaline center of coastal upwelling shifts to the east of Dongshan Island and expanded to offshore waters in comparison with previous records. A total of 137 phytoplankton species belonging to 59 genera in 4 phyla are identified excluding the unidentified species. Diatom is the first major group and followed by dinoflagellate. Cyanobacteria mainly composed by three Trichodesmium species account for a certain proportions, while Chrysophyta are only found in offshore waters. The dominant species include Thalassionema nitzschioides, Pseudo-nitzschia pungens, Thalassionema frauenfeldii, Pseudo-nitzschia delicatissima, Rhizosolenia styliformis, Chaetoceros curvisetus, Diplopsalis lenticula and Trichodesmium thiebautii. Phytoplankton community mainly consists of eurythermal and eurytopic species, followed by warm-water species, tropic high-salinity species and oceanic eurythermic species in order. Phytoplankton abundance ranges from 1.00 × 102 ind./L ~ 437.22 × 102 ind./L with an average of 47.36 × 102 ind./L. For vertical distribution, maximum abundance is found at 30 m-depth and the surface comes second. Besides, the abundance below 30 m

Trends in the number of extreme hot SST days along the Canary Upwelling System due to the influence of upwelling

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Xurxo Costoya

2014-07-01

Full Text Available Trends in the number of extreme hot days (days with SST anomalies higher than the 95% percentile were analyzed along the Canary Upwelling Ecosystem (CUE over the period 1982- 2012 by means of SST data retrieved from NOAA OI1/4 Degree. The analysis will focus on the Atlantic Iberian sector and the Moroccan sub- region where upwelling is seasonal (spring and summer are permanent, respectively. Trends were analyzed both near coast and at the adjacent ocean where the increase in the number of extreme hot days is higher. Changes are clear at annual scale with an increment of 9.8±0.3 (9.7±0.1 days dec-1 near coast and 11.6±0.2 (13.5±0.1 days dec-1 at the ocean in the Atlantic Iberian sector (Moroccan sub-region. The differences between near shore and ocean trends are especially patent for the months under intense upwelling conditions. During that upwelling season the highest differences in the excess of extreme hot days between coastal and ocean locations (Δn(#days dec-1 occur at those regions where coastal upwelling increase is high. Actually, Δn and upwelling trends have shown to be significantly correlated in both areas, R=0.88 (p<0.01 at the Atlantic Iberian sector and R=0.67 (p<0.01 at the Moroccan sub-region.

Atmosphere-ocean feedbacks in a coastal upwelling system

Science.gov (United States)

Alves, J. M. R.; Peliz, A.; Caldeira, R. M. A.; Miranda, P. M. A.

2018-03-01

The COAWST (Coupled Ocean-Atmosphere-Wave-Sediment Transport) modelling system is used in different configurations to simulate the Iberian upwelling during the 2012 summer, aiming to assess the atmosphere-ocean feedbacks in the upwelling dynamics. When model results are compared with satellite measurements and in-situ data, two-way coupling is found to have a moderate impact in data-model statistics. A significant reinforcement of atmosphere-ocean coupling coefficients is, however, observed in the two-way coupled run, and in the WRF and ROMS runs forced by previously simulated SST and wind fields, respectively. The increasing in the coupling coefficient is associated with slight, but potentially important changes in the low-level coastal jet in the atmospheric marine boundary layer. While these results do not imply the need for fully coupled simulations in many applications, they show that in seasonal numerical studies such simulations do not degrade the overall model performance, and contribute to produce better dynamical fields.

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

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

2013-02-01

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

Gradients in microbial methanol uptake: productive coastal upwelling waters to oligotrophic gyres in the Atlantic Ocean

Science.gov (United States)

Dixon, Joanna L; Sargeant, Stephanie; Nightingale, Philip D; Colin Murrell, J

2013-01-01

Methanol biogeochemistry and its importance as a carbon source in seawater is relatively unexplored. We report the first microbial methanol carbon assimilation rates (k) in productive coastal upwelling waters of up to 0.117±0.002 d−1 (∼10 nmol l−1 d−1). On average, coastal upwelling waters were 11 times greater than open ocean northern temperate (NT) waters, eight times greater than gyre waters and four times greater than equatorial upwelling (EU) waters; suggesting that all upwelling waters upon reaching the surface (⩽20 m), contain a microbial population that uses a relatively high amount of carbon (0.3–10 nmol l−1 d−1), derived from methanol, to support their growth. In open ocean Atlantic regions, microbial uptake of methanol into biomass was significantly lower, ranging between 0.04–0.68 nmol l−1 d−1. Microbes in the Mauritanian coastal upwelling used up to 57% of the total methanol for assimilation of the carbon into cells, compared with an average of 12% in the EU, and 1% in NT and gyre waters. Several methylotrophic bacterial species were identified from open ocean Atlantic waters using PCR amplification of mxaF encoding methanol dehydrogenase, the key enzyme in bacterial methanol oxidation. These included Methylophaga sp., Burkholderiales sp., Methylococcaceae sp., Ancylobacter aquaticus, Paracoccus denitrificans, Methylophilus methylotrophus, Methylobacterium oryzae, Hyphomicrobium sp. and Methylosulfonomonas methylovora. Statistically significant correlations for upwelling waters between methanol uptake into cells and both chlorophyll a concentrations and methanol oxidation rates suggest that remotely sensed chlorophyll a images, in these productive areas, could be used to derive total methanol biological loss rates, a useful tool for atmospheric and marine climatically active gas modellers, and air–sea exchange scientists. PMID:23178665

Why coastal upwelling is expected to increase along the western Iberian Peninsula over the next century?

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Sousa, Magda Catarina; deCastro, Maite; Alvarez, Ines; Gomez-Gesteira, Moncho; Dias, João Miguel

2017-08-15

Former studies about coastal upwelling along the Western Iberian Peninsula (WIP) using historical data indicated contradictory results, showing either its strengthening or reduction, while previous studies using Global Climate Models (GCMs) indicated that global warming is likely to intensify this phenomenon although predicting different rates and not justifying the patterns found. Taking advantage of the recent high spatial resolution Regional Climate Models (RCMs) projections from EURO-CORDEX project (Representative Concentration Pathway, RCP 8.5), detailed higher accuracy estimations of the spatio-temporal trends of Upwelling Index (UI) along the WIP coast were performed in this study, integrating the coastal mesoscale effects within the framework of climate change. Additionally, this research brings new insights about the origin of the WIP coastal upwelling intensification over the next century. These new projections clarified the upwelling strengthening rates predicted along the coast of the WIP from 2006 to 2099 revealing more prominent changes in the northern limit of the region (25-30m 3 s -1 km -1 per decade between 41.5 and 42.5°N). Trends observed at high latitudes of the region were found to be induced by the displacement of the Azores High, which will intensify (0.03hPa per decade) and drift northeastward (10km per decade) during the 21st century. Copyright © 2017 Elsevier B.V. All rights reserved.

Compound-specific δ15N amino acid measurements in littoral mussels in the California upwelling ecosystem: a new approach to generating baseline δ15N Isoscapes for coastal ecosystems.

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Natasha L Vokhshoori

Full Text Available We explored δ(15N compound-specific amino acid isotope data (CSI-AA in filter-feeding intertidal mussels (Mytilus californianus as a new approach to construct integrated isoscapes of coastal primary production. We examined spatial δ(15N gradients in the California Upwelling Ecosystem (CUE, determining bulk δ(15N values of mussel tissue from 28 sites between Port Orford, Oregon and La Jolla, California, and applying CSI-AA at selected sites to decouple trophic effects from isotopic values at the base of the food web. Bulk δ(15N values showed a strong linear trend with latitude, increasing from North to South (from ∼ 7‰ to ∼ 12‰, R(2 = 0.759. In contrast, CSI-AA trophic position estimates showed no correlation with latitude. The δ(15N trend is therefore most consistent with a baseline δ(15N gradient, likely due to the mixing of two source waters: low δ(15N nitrate from the southward flowing surface California Current, and the northward transport of the California Undercurrent (CUC, with (15N-enriched nitrate. This interpretation is strongly supported by a similar linear gradient in δ(15N values of phenylalanine (δ(15NPhe, the best AA proxy for baseline δ(15N values. We hypothesize δ(15N(Phe values in intertidal mussels can approximate annual integrated δ(15N values of coastal phytoplankton primary production. We therefore used δ(15N(Phe values to generate the first compound-specific nitrogen isoscape for the coastal Northeast Pacific, which indicates a remarkably linear gradient in coastal primary production δ(15N values. We propose that δ(15N(Phe isoscapes derived from filter feeders can directly characterize baseline δ(15N values across major biochemical provinces, with potential applications for understanding migratory and feeding patterns of top predators, monitoring effects of climate change, and study of paleo- archives.

Resource partitioning within major bottom fish species in a highly productive upwelling ecosystem

Science.gov (United States)

Abdellaoui, Souad; El Halouani, Hassan; Tai, Imane; Masski, Hicham

2017-09-01

The Saharan Bank (21-26°N) is a wide subtropical continental shelf and a highly productive upwelling ecosystem. The bottom communities are dominated by octopus and sparid fish, which are the main targets of bottom-trawl fishing fleets. To investigate resource partitioning within the bottom fish community, adult fish from 14 of the most abundant species were investigated for stomach content analysis. Samples were collected during two periods: October 2003 and May 2007. The diet of the analysed species showed more variation between periods than between size classes, suggesting that temporal or spatial variability in prey availability appears to play a significant role in their diet. Multivariate analysis and subsequent clustering led to a grouping of the species within five trophic guilds. Two species were fish feeders, and the others mainly fed on benthic invertebrates, where epibenthic crustaceans, lamellibranchs and fish were the most important groups in defining trophic guilds. We found that the studied species had a high rate of overlapping spatial distributions and overlapping trophic niches. In this highly productive upwelling ecosystem, where food resources may not be a limiting factor, inter-specific competition did not appear to be an important factor in structuring bottom fish communities. For the species that showed differences in the proportions of prey categories in comparison with other ecosystems, the rise of the proportion of epibenthic crustaceans in their diet was a common feature; a possible consequence of the benthic productivity of this highly productive upwelling ecosystem.

Regeneration of nitrogen by zooplankton and fish in the Northwest Africa and Peru upwelling ecosystems

Energy Technology Data Exchange (ETDEWEB)

Whitledge, T E

1976-01-01

The availability of nutrients and light are the dominant controlling factors of the levels of primary production in the ocean. In the lower latitudes where most coastal upwelling areas are located, the amount of light is seldom below the critical level to inhibit productivity so nutrients are often the limiting factor in phytoplankton growth. Nutrients utilized in primary productivity are derived from two sources in upwelling areas. Nutrients are introduced to the euphotic zone from depth by the physical processes that create upwelling and nutrients are recycled by biological organisms that inhabit the area. Nitrate introduced into the euphotic zone by upwelling supports new productivity while ammonium and other excretory products regenerated by zooplankton and nekton supports regenerated productivity. Results are reported from studies off the coast of Northwest Africa and Peru using /sup 15/N as a tracer that showed that recycled ammonium may fulfill nearly half of the daily nitrogen requirement of phytoplankton and upwelled nitrate may provide the other half.

Multiple stressors, nonlinear effects and the implications of climate change impacts on marine coastal ecosystems.

Science.gov (United States)

Hewitt, Judi E; Ellis, Joanne I; Thrush, Simon F

2016-08-01

Global climate change will undoubtedly be a pressure on coastal marine ecosystems, affecting not only species distributions and physiology but also ecosystem functioning. In the coastal zone, the environmental variables that may drive ecological responses to climate change include temperature, wave energy, upwelling events and freshwater inputs, and all act and interact at a variety of spatial and temporal scales. To date, we have a poor understanding of how climate-related environmental changes may affect coastal marine ecosystems or which environmental variables are likely to produce priority effects. Here we use time series data (17 years) of coastal benthic macrofauna to investigate responses to a range of climate-influenced variables including sea-surface temperature, southern oscillation indices (SOI, Z4), wind-wave exposure, freshwater inputs and rainfall. We investigate responses from the abundances of individual species to abundances of functional traits and test whether species that are near the edge of their tolerance to another stressor (in this case sedimentation) may exhibit stronger responses. The responses we observed were all nonlinear and some exhibited thresholds. While temperature was most frequently an important predictor, wave exposure and ENSO-related variables were also frequently important and most ecological variables responded to interactions between environmental variables. There were also indications that species sensitive to another stressor responded more strongly to weaker climate-related environmental change at the stressed site than the unstressed site. The observed interactions between climate variables, effects on key species or functional traits, and synergistic effects of additional anthropogenic stressors have important implications for understanding and predicting the ecological consequences of climate change to coastal ecosystems. © 2015 John Wiley & Sons Ltd.

Diversity and Transcriptional Levels of RuBisCO Form II of Sulfur-Oxidizing γ-Proteobacteria in Coastal-Upwelling Waters with Seasonal Anoxia

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Bárbara Léniz

2017-07-01

Full Text Available Seasonal wind-driven upwelling, high primary production in surface waters, and oxygen deficiency in subsurface waters characterize the coastal ecosystem of the subtropical eastern South Pacific (ESP, and shape the nature and dynamics of the microbial community structure and function. We investigated the diversity, abundance, and transcriptional levels of the gene encoding the large subunit form II of the RuBisCO enzyme (cbbM in the pelagic microbial community at a continental-shelf site off central Chile over 2 years. We focused on cbbM genes affiliated with the sulfur-oxidizing γ-proteobacteria cluster, whose members are known to dominate in oxygen-deficient marine environments and are highly abundant in the study area. Phylogenetic analysis of cbbM sequences suggests the presence of a novel group of chemolithoautotrophs, closely related to the SUP05/ARCTIC96BD-19 clade. Through (RT-qPCR, we studied the cbbM gene abundance and transcript dynamics over an annual cycle, finding a significantly higher number of cbbM copies per unit volume in months of active upwelling and at depths in which oxygen was scarce or absent. The same temporal pattern was observed at the transcriptional level. We also analyzed the relative expression of key genes for carbon, nitrogen and sulfur cycling in six metatranscriptomic datasets, for two characteristic periods within the annual cycle: the anoxic upwelling and the suboxic downwelling. Our results indicate that coastal waters of the subtropical ESP contain transcriptionally active populations of carbon fixing pelagic bacteria, whose dynamics is controlled, in large part, by fluctuations in oxygen levels. They also suggest that chemolithoautotrophic processes coupled to the sulfur and nitrogen cycles become increasingly important for the carbon economy of marine coastal waters as oxygen concentrations decline.

Discriminating the biophysical impacts of coastal upwelling and mud banks along the southwest coast of India

Digital Repository Service at National Institute of Oceanography (India)

Karnan, C.; Jyothibabu, R.; Arunpandi, N.; Jagadeesan, L.; Muraleedharan, K.R.; Pratihary, A.K.; Balachandran, K.K.; Naqvi, S.W.A.

Coastal upwelling and mud banks are two oceanographic processes concurrently operating along certain stretches of the southwest (Kerala) coast of India during the Southwest Monsoon period (June-September), facilitating significant enhancement...

Spatiotemporal variation of vertical particle fluxes and modelled chlorophyll a standing stocks in the Benguela Upwelling System

Science.gov (United States)

Vorrath, Maria-Elena; Lahajnar, Niko; Fischer, Gerhard; Libuku, Viktor Miti; Schmidt, Martin; Emeis, Kay-Christian

2018-04-01

Marine particle fluxes from high productive coastal upwelling systems return upwelled CO2 and nutrients to the deep ocean and sediments and have a substantial impact on the global carbon cycle. This study examines relations between production regimes on the shelf and over the continental margin of the Benguela Upwelling System (BUS) in the SE Atlantic Ocean. Data of composition and timing of vertical particle flux come from sediment trap time series (deployed intermittently between 1988 and 2014) in the regions Walvis Ridge, Walvis Bay, Luederitz and Orange River. We compare their seasonal variability to modelled patterns of chlorophyll concentrations in a 3-D ecosystem model. Both modelled seasonal chlorophyll a standing stocks and sampled particle flux patterns are highly correspondent with a bimodal seasonal cycle offshore the BUS. The material in the particle flux in offshore traps is dominantly carbonate (40-70%), and flux peaks in offshore particle flux originate from two independent events: in austral autumn thermocline shoaling and vertical mixing are decoupled from coastal upwelling, while fluxes in spring coincide with the upwelling season, indicated by slightly elevated biogenic opal values at some locations. Coastal particle fluxes are characterized by a trimodal pattern and are dominated by biogenic opal (22-35%) and organic matter (30-60%). The distinct seasonality in observed fluxes on the shelf is caused by high variability in production, sinking behaviour, wind stress, and hydrodynamic processes. We speculate that global warming will increase ocean stratification and alter coastal upwelling, so that consequences for primary production and particle flux in the BUS are inevitable.

Shifts between gelatinous and crustacean plankton in a coastal upwelling region

OpenAIRE

Bode, Antonio; Álvarez-Ossorio, Maria Teresa; Miranda, Ana; Ruiz-Villarreal, Manuel

2013-01-01

proyectos RADIALES (IEO) y EURO-BASIN (Ref. 264933, 7FP) Variability in the dominance of copepods vs. gelatinous plankton was analysed using monthly time-series covering the last 55 years and related to changes in climatic, oceanographic, and fishery conditions in the upwelling region of Galicia (NW Spain). Seasonality was generally the main component of variability in all groups, both along the coast and in the nearby ocean, but no common long-term trend was found. Coastal copepo...

Scales and sources of pH and dissolved oxygen variability in a shallow, upwelling-driven ecosystem

Science.gov (United States)

Tanner, C. A.; Martz, T.; Levin, L. A.

2011-12-01

In the coastal zone extreme variability in carbonate chemistry and oxygen is driven by fluctuations in temperature, salinity, air-sea gas exchange, mixing processes, and biology. This variability appears to be magnified in upwelling-driven ecosystems where low oxygen and low pH waters intrude into shallow depths. The oxygen and carbon chemistry signal can be further confounded by highly productive ecosystems such as kelp beds where photosynthesis and respiration consume and release significant amounts of dissolved inorganic carbon and oxygen. This variability poses a challenge for scientists assessing the impacts of climate change on nearshore ecosystems. We deployed physical & biogeochemical sensors in order to observe these processes in situ. The "SeapHOx" instruments used in this study consist of a modified Honeywell Durafet° ISFET pH sensor, an Aanderra Optode Oxygen sensor, and a SBE-37 conductivity, temperature, pressure sensor. The instruments were deployed on and around the La Jolla Kelp Forest at a variety of depths. Our goals were to (a) characterize the link between pH and oxygen and identify the magnitude of pH and oxygen variability over a range of intra-annual time scales and (b) investigate spatial patterns of pH and oxygen variability associated with depth, proximity to shore, and presence of kelp. Results thus far reveal a strong relationship between oxygen and pH. Temporal variability is greatest at the semidiurnal frequency where pH (at 7 m) can range up to 0.3 units and oxygen can change 50% over 6 h. Diurnal variability is a combination of the diurnal tidal component and diel cycles of production and respiration. Event-scale dynamics associated with upwelling can maintain pH and oxygen below 7.8 units and 200 μmol kg-1, respectively, for multiple days. Frequent current reversals drive changes in the observed oxygen and pH variability. When alongshore currents are flowing southward, driven by upwelling-favorable winds, the magnitude of

Patterns of copepod diversity in the Chilean coastal upwelling system

Science.gov (United States)

Hidalgo, Pamela; Escribano, Ruben; Vergara, Odette; Jorquera, Erika; Donoso, Katty; Mendoza, Paula

2010-12-01

The copepod community structure from the Northern and Central/southern upwelling regions off Chile was studied and compared. The derived community descriptors were species abundance (N), species richness (R) and the Shannon-Wiener diversity index (H'). These descriptors were related to distinct habitats and conditions, sea surface temperature (SST) and depth of the upper boundary of the oxygen minimum zone (OMZ). From 159 samples, obtained between 2002 and 2008, a total number of 118 species were found of which the calanoids Paracalanus indicus, Acartia tonsa and Eucalanus inermis, along with the cyclopoid Oithona similis, and the poecilostomatoids Triconia conifera and Oncaea media were the dominant species. H' was higher in the northern region, but no differences in N and R were detected between regions. N was higher in the epipelagic vs the deep habitat, but R and H' did not differ. N, R and H' correlated positively to SST and negatively to OMZ depth. The ascent of the OMZ to the upper layer forced by upwelling was proposed as a mechanism that aggregates and increases copepod diversity in the food-rich photic zone. All these findings suggest a fundamental role of upwelling variation for modulating copepod dynamics and community structure in this highly productive but strongly variable marine ecosystem.

Climate warming and estuarine and marine coastal ecosystems

International Nuclear Information System (INIS)

Kennedy, V.S.

1994-01-01

Estuaries are physically controlled, resilient coastal ecosystems harboring environmentally tolerant species in diluted seawater. Marine coastal systems are less stressed physically and contain some environmentally less tolerant species. Both systems are biologically productive and economically significant. Because of their complex structure and function, it is difficult to predict accurately the effects of climate change, but some broad generalizations can be made. If climate warming occurs, it will raise sea-level, heat shallow waters, and modify precipitation, wind, and water circulation patterns. Rapid sea-level rise could cause the loss of salt marshes, mangrove swamps, and coral reefs, thus diminishing the ecological roles of these highly productive systems. Warmer waters could eliminate heat-sensitive species from part of their geographical range while allowing heat-tolerant species to expand their range, depending on their ability to disperse. Most thermally influenced losses of species will probably only be local, but changed distributions may lead to changed community function. It is more difficult to predict the effects of modified precipitation, wind, and water circulation patterns, but changes could affect organisms dependent on such patterns for food production (e.g., in upwelling regions) or for retention in estuaries. Aquacultural and fishery-related enterprises would be affected negatively in some regions and positively in others. 73 refs

Variability of coastal water hydrodynamics in the southern Baltic - hindcast modelling of an upwelling event along the Polish coast

Directory of Open Access Journals (Sweden)

Andrzej Jankowski

2002-12-01

Full Text Available This paper presents the results of an attempt to reproduce, with theaid of a numerical circulation model, the hydrological conditions observedin the coastal area of the southern Baltic in September 1989.A large fall in surface layer seawater temperature was recordedin September 1989 at two coastal stations in the vicinity ofKolobrzeg and Wladyslawowo. This upwelling-like phenomenon was assumed tobe related to the specific anemobaric situation in September 1989,however typical of this phenomenon to occur along the Polish Baltic coast(Malicki & Mietus 1994. A three-dimensional (3-D sigma-coordinatebaroclinic model of the Baltic Sea, with a horizontal resolution of~5 km and 24 sigma-levels in the vertical, was applied to investigatewater circulation and thermohaline variability. Hindcastnumerical simulation showed that the model provided a good reproductionof the temporal history of the surface seawater temperature and theduration of the upwelling-like fall, but that the model results wereunderestimated. The maxima of this large fall in the surface layertemperature at both coastal stations are closely related to the phase ofchange of the upwelling-favourable wind direction to the opposite one.The results of simulation runs showed details of upwelling developmentdue to wind field fluctuations in time and differences in shaping thetemperature and current patterns in conjunction with the variations intopography and coastline features in some areas along the Polish coast.Two different hydrodynamic regimes of water movements along the coastresulting from topographical features (the Slupsk Bank can be distinguished.From the model simulation the specific conditions for the occurrence anddevelopment of upwelling at the eastern end of the Polish coast(in the vicinity of Wladyslawowo can be deduced.

Transport of terrigenous polycyclic aromatic hydrocarbons affected by the coastal upwelling in the northwestern coast of South China Sea.

Science.gov (United States)

Ya, Miaolei; Wu, Yuling; Li, Yongyu; Wang, Xinhong

2017-10-01

Coastal upwelling prevails in the coast of Hainan Island, the northern South China Sea (SCS) during summer. We studied the influences of the upwelling on the horizontal and vertical transport of terrigenous polycyclic aromatic hydrocarbons (PAHs). PAHs in dissolved and suspended particulate phase of water samples were determined in the upper (depth  10 m). PAH levels decreased sharply from inshore to offshore to open sea. The results showed that terrestrial input was the main source of coastal PAHs. Perylene, an important indicator of land plant-derived PAH, showed the significant correlation with PAHs (p sea. Copyright © 2017 Elsevier Ltd. All rights reserved.

SCOR Working Group 137: "Global Patterns of Phytoplankton Dynamics in Coastal Ecosystems": An introduction to the special issue of Estuarine, Coastal and Shelf Science

Science.gov (United States)

Paerl, Hans W.; Yin, Kedong; O'Brien, Todd D.

2015-09-01

Phytoplankton form the base of most aquatic food webs and play a central role in assimilation and processing of carbon and nutrients, including nitrogen, phosphorus, silicon, iron and a wide range of trace elements (Reynolds, 2006). In the marine environment, estuarine and coastal ecosystems (jointly termed coastal here) are among the most productive, resourceful and dynamic habitats on Earth (Malone et al., 1999; Day et al., 2012). These ecosystems constitute only ∼10% of the global oceans' surface, but account for over 30% of its primary production (Day et al., 2012). They process vast amounts of nutrients, sediments, carbonaceous, and xenobiotic compounds generated in coastal watersheds, in which approximately 70% of the world's human population resides (Nixon, 1995; Vitousek et al., 1997; NOAA, 2013). Estuarine and coastal ecosystems are also strongly influenced by localized nutrient enrichment from coastal upwelling, with major impacts on the structure and function of phytoplankton communities and the food webs they support (Legendre and Rassoulzadegan, 2012; Paerl and Justić, 2012). In addition, introductions and invasions of exotic plant and animal species have led to significant "top down" mediated changes in phytoplankton community structure and function (Carlton, 1999; Thompson, 2005). Lastly, the coastal zone is the "front line" of climatically-induced environmental change, including warming, altered rainfall patterns, intensities and magnitudes (Trenberth, 2005; IPCC, 2012), which jointly impact phytoplankton community structure and function (Cloern and Jassby, 2012; Hall et al., 2013). The combined effects of these pressures translate into a myriad of changes in phytoplankton production and community structure along geomorphological and geographic gradients (Fig. 1), with cascading quantitative and qualitative impacts on biogeochemical cycling, food web structure and function, water quality and overall resourcefulness and sustainability of these

Biological response to coastal upwelling and dust deposition in the area off Northwest Africa

Science.gov (United States)

Ohde, T.; Siegel, H.

2010-05-01

Nutrient supply in the area off Northwest Africa is mainly regulated by two processes, coastal upwelling and deposition of Saharan dust. In the present study, both processes were analyzed and evaluated by different methods, including cross-correlation, multiple correlation, and event statistics, using remotely sensed proxies of the period from 2000 to 2008 to investigate their influence on the marine environment. The remotely sensed chlorophyll- a concentration was used as a proxy for the phytoplankton biomass stimulated by nutrient supply into the euphotic zone from deeper water layers and from the atmosphere. Satellite-derived alongshore wind stress and sea-surface temperature were applied as proxies for the strength and reflection of coastal upwelling processes. The westward wind and the dust component of the aerosol optical depth describe the transport direction of atmospheric dust and the atmospheric dust column load. Alongshore wind stress and induced upwelling processes were most significantly responsible for the surface chlorophyll- a variability, accounting for about 24% of the total variance, mainly in the winter and spring due to the strong north-easterly trade winds. The remotely sensed proxies allowed determination of time lags between biological response and its forcing processes. A delay of up to 16 days in the surface chlorophyll- a concentration due to the alongshore wind stress was determined in the northern winter and spring. Although input of atmospheric iron by dust storms can stimulate new phytoplankton production in the study area, only 5% of the surface chlorophyll- a variability could be ascribed to the dust component in the aerosol optical depth. All strong desert storms were identified by an event statistics in the time period from 2000 to 2008. The 57 strong storms were studied in relation to their biological response. Six events were clearly detected in which an increase of chlorophyll- a was caused by Saharan dust input and not by

Regime shifts and resilience in China's coastal ecosystems.

Science.gov (United States)

Zhang, Ke

2016-02-01

Regime shift often results in large, abrupt, and persistent changes in the provision of ecosystem services and can therefore have significant impacts on human wellbeing. Understanding regime shifts has profound implications for ecosystem recovery and management. China's coastal ecosystems have experienced substantial deterioration within the past decades, at a scale and speed the world has never seen before. Yet, information about this coastal ecosystem change from a dynamics perspective is quite limited. In this review, I synthesize existing information on coastal ecosystem regime shifts in China and discuss their interactions and cascading effects. The accumulation of regime shifts in China's coastal ecosystems suggests that the desired system resilience has been profoundly eroded, increasing the potential of abrupt shifts to undesirable states at a larger scale, especially given multiple escalating pressures. Policy and management strategies need to incorporate resilience approaches in order to cope with future challenges and avoid major losses in China's coastal ecosystem services.

Upwelling events, coastal offshore exchange, links to biogeochemical processes - Highlights from the Baltic Sea Science Congress

Directory of Open Access Journals (Sweden)

Bogdan Ołdakowski

2008-03-01

Full Text Available The Baltic Sea Science Congress was held at Rostock University, Germany, from 19 to 22 March 2007. In the session entitled"Upwelling events, coastal offshore exchange, links to biogeochemical processes" 20 presentations were given,including 7 talks and 13 posters related to the theme of the session.This paper summarises new findings of the upwelling-related studies reported in the session. It deals with investigationsbased on the use of in situ and remote sensing measurements as well as numerical modelling tools. The biogeochemicalimplications of upwelling are also discussed.Our knowledge of the fine structure and dynamic considerations of upwelling has increased in recent decades with the advent ofhigh-resolution modern measurement techniques and modelling studies. The forcing and the overall structure, duration and intensity ofupwelling events are understood quite well. However, the quantification of related transports and the contribution to the overall mixingof upwelling requires further research. Furthermore, our knowledge of the links between upwelling and biogeochemical processes is stillincomplete. Numerical modelling has advanced to the extent that horizontal resolutions of c. 0.5 nautical miles can now be applied,which allows the complete spectrum of meso-scale features to be described. Even the development of filaments can be describedrealistically in comparison with high-resolution satellite data.But the effect of upwelling at a basin scale and possible changes under changing climatic conditions remain open questions.

How coastal upwelling influences spatial patterns of size-structured diversity of copepods off central-southern Chile (summer 2009)

Science.gov (United States)

Hidalgo, Pamela; Escribano, Ruben; Fuentes, Marcelo; Jorquera, Erika; Vergara, Odette

2012-01-01

This study assessed the structure of the copepod community in the upper 200 m of the coastal upwelling region off central-southern Chile in late summer 2009. Vertically stratified zooplankton samples and hydrographic variables were obtained from 42 stations over the continental shelf and oceanic areas. The survey took place during active upwelling, reflected by a cold upwelling plume extending out to 150 km offshore. A total of 62 copepod species were found. Of these, Oithona similis and Paracalanusindicus accounted for ca. 60% of the whole community. Species richness ( R) and the Shannon-Wiener diversity index ( H‧) were estimated, and the latter was additionally modified to incorporate the effect of copepod size on diversity ( H‧ s). Samples were analyzed for two depth strata (0-50, 50-200 m) and for day vs. night conditions. Significant effects of day vs. night and strata on R, H‧ and H‧ s indicated that diel vertical migration between these two layers was an important source of variation in the zooplankton community. H‧ s seemed to represent copepod diversity better than R and H‧ over the spatial scale. H‧ s was also closely linked to colder upwelled water and the depth of the oxygen minimum zone following a principal component analysis. A positive relationship was even detected between depth of the oxygen minimum zone and H‧ s when strata and day/night effects were excluded. Our findings suggested that the coastal upwelling process could be an important driver of copepod diversity in this region. Upwelling leads to changes in the depth of the oxygen minimum zone and these changes impact the community composition due to species-dependent tolerances to low oxygen water.

Coastal ecosystems: Attempts to manage a threatened resource

International Nuclear Information System (INIS)

Lundin, C.G.; Linden, O.

1993-01-01

Tropical coastal zones are productive ecosystems that currently face severe environmental threats, particularly from organic pollution. The role of the coastal ecosystems is analyzed and the relationship between coastal ecosystem health and fisheries productivity is explained. Ecological disturbances from organic sources like sewage and siltation is highlighted. The issues of integrated coastal zone management (ICZM) are discussed, particularly in the context of conserving natural ecosystems or transforming them to managed systems. Issues of population density, management capacity, and socioeconomic conditions are discussed. The possibilities for closing carbon cycles currently leaking organic materials to the coastal waters are pursued. Finally, examples of ICZM initiatives in the ASEAN countries and East Africa are presented. 42 refs

Relative contributions of local wind and topography to the coastal upwelling intensity in the northern South China Sea

Science.gov (United States)

Wang, Dongxiao; Shu, Yeqiang; Xue, Huijie; Hu, Jianyu; Chen, Ju; Zhuang, Wei; Zu, TingTing; Xu, Jindian

2014-04-01

Topographically induced upwelling caused by the interaction between large-scale currents and topography was observed during four cruises in the northern South China Sea (NSCS) when the upwelling favorable wind retreated. Using a high-resolution version of the Princeton Ocean Model, we investigate relative contributions of local wind and topography to the upwelling intensity in the NSCS. The results show that the topographically induced upwelling is sensitive to alongshore large-scale currents, which have an important contribution to the upwelling intensity. The topographically induced upwelling is comparable with the wind-driven upwelling at surface and has a stronger contribution to the upwelling intensity than the local wind does at bottom in the near-shore shelf region. The widened shelf to the southwest of Shanwei and west of the Taiwan Banks intensifies the bottom friction, especially off Shantou, which is a key factor for topographically induced upwelling in terms of bottom Ekman transport and Ekman pumping. The local upwelling favorable wind enhances the bottom friction as well as net onshore transport along the 50 m isobath, whereas it has less influence along the 30 m isobath. This implies the local wind is more important in upwelling intensity in the offshore region than in the nearshore region. The contribution of local upwelling favorable wind on upwelling intensity is comparable with that of topography along the 50 m isobath. The effects of local upwelling favorable wind on upwelling intensity are twofold: on one hand, the wind transports surface warm water offshore, and as a compensation of mass the bottom current transports cold water onshore; on the other hand, the wind enhances the coastal current, and the bottom friction in turn increases the topographically induced upwelling intensity.

Alkaline phosphatase activity at the southwest coast of India: A comparison of locations differently affected by upwelling

Science.gov (United States)

Mamatha, S. S.; Malik, Ashish; Varik, Sandesh; Parvathi, V.; Jineesh, V. K.; Gauns, Mangesh U.; LokaBharathi, P. A.

2015-01-01

The realization of the potential importance of phosphorus (P) as a limiting nutrient in marine ecosystem is increasing globally. Hence, the contribution of biotic variables in mobilizing this nutrient would be relevant especially in productive coastal waters. As alkaline phosphatase activity (APA) indicates the status of P for primary production in aquatic environments, we asked the following question: is the level of APA indicative of P sufficiency or deficiency in coastal waters, especially, where upwelling is a regular phenomenon? Therefore, we have examined the total APA, chlorophyll a along with phosphatase producing bacteria (PPB) and related environmental parameters from nearshore to offshore in coastal waters off Trivandrum and Kochi regions differently affected by upwelling during the onset of monsoon. Off Trivandrum, APA in the offshore waters of 5-m layer at 2.23 μM P h- 1 was > 4 times higher than nearshore. Thus, low APA could be indicative of P sufficiency in coastal waters and higher activity suggestive of deficiency in offshore waters off Trivandrum. In contrast, there was less difference in APA between near and offshore surface waters off Kochi. Our results show that the regions differently affected by upwelling respond differently according to ambient P concentration, distance from shore or depth of water. These observations could apparently be applicable to other coastal systems as well, where gradients in upwelling and phosphate runoff have been noticed. Further studies on other transects would throw more light on the extent and direction of the relationship between APA and ambient P concentration. Such studies would help in understanding the level of control of this nutrient on the productivity of coastal waters.

Global patterns of phytoplankton dynamics in coastal ecosystems

Science.gov (United States)

Paerl, H.; Yin, Kedong; Cloern, J.

2011-01-01

Scientific Committee on Ocean Research Working Group 137 Meeting; Hangzhou, China, 17-21 October 2010; Phytoplankton biomass and community structure have undergone dramatic changes in coastal ecosystems over the past several decades in response to climate variability and human disturbance. These changes have short- and long-term impacts on global carbon and nutrient cycling, food web structure and productivity, and coastal ecosystem services. There is a need to identify the underlying processes and measure the rates at which they alter coastal ecosystems on a global scale. Hence, the Scientific Committee on Ocean Research (SCOR) formed Working Group 137 (WG 137), "Global Patterns of Phytoplankton Dynamics in Coastal Ecosystems: A Comparative Analysis of Time Series Observations" (http://wg137.net/). This group evolved from a 2007 AGU-sponsored Chapman Conference entitled "Long Time-Series Observations in Coastal Ecosystems: Comparative Analyses of Phytoplankton Dynamics on Regional to Global Scales.".

Human-mediated drivers of change — impacts on coastal ...

African Journals Online (AJOL)

Human-mediated drivers of change — impacts on coastal ecosystems and marine ... of global change because they are located at the land–ocean interface and ... upwelling regimes are all being affected by human-mediated climate change.

Economic development and coastal ecosystem change in China

Science.gov (United States)

He, Qiang; Bertness, Mark D.; Bruno, John F.; Li, Bo; Chen, Guoqian; Coverdale, Tyler C.; Altieri, Andrew H.; Bai, Junhong; Sun, Tao; Pennings, Steven C.; Liu, Jianguo; Ehrlich, Paul R.; Cui, Baoshan

2014-01-01

Despite their value, coastal ecosystems are globally threatened by anthropogenic impacts, yet how these impacts are driven by economic development is not well understood. We compiled a multifaceted dataset to quantify coastal trends and examine the role of economic growth in China's coastal degradation since the 1950s. Although China's coastal population growth did not change following the 1978 economic reforms, its coastal economy increased by orders of magnitude. All 15 coastal human impacts examined increased over time, especially after the reforms. Econometric analysis revealed positive relationships between most impacts and GDP across temporal and spatial scales, often lacking dropping thresholds. These relationships generally held when influences of population growth were addressed by analyzing per capita impacts, and when population density was included as explanatory variables. Historical trends in physical and biotic indicators showed that China's coastal ecosystems changed little or slowly between the 1950s and 1978, but have degraded at accelerated rates since 1978. Thus economic growth has been the cause of accelerating human damage to China's coastal ecosystems. China's GDP per capita remains very low. Without strict conservation efforts, continuing economic growth will further degrade China's coastal ecosystems. PMID:25104138

Economic development and coastal ecosystem change in China.

Science.gov (United States)

He, Qiang; Bertness, Mark D; Bruno, John F; Li, Bo; Chen, Guoqian; Coverdale, Tyler C; Altieri, Andrew H; Bai, Junhong; Sun, Tao; Pennings, Steven C; Liu, Jianguo; Ehrlich, Paul R; Cui, Baoshan

2014-08-08

Despite their value, coastal ecosystems are globally threatened by anthropogenic impacts, yet how these impacts are driven by economic development is not well understood. We compiled a multifaceted dataset to quantify coastal trends and examine the role of economic growth in China's coastal degradation since the 1950s. Although China's coastal population growth did not change following the 1978 economic reforms, its coastal economy increased by orders of magnitude. All 15 coastal human impacts examined increased over time, especially after the reforms. Econometric analysis revealed positive relationships between most impacts and GDP across temporal and spatial scales, often lacking dropping thresholds. These relationships generally held when influences of population growth were addressed by analyzing per capita impacts, and when population density was included as explanatory variables. Historical trends in physical and biotic indicators showed that China's coastal ecosystems changed little or slowly between the 1950s and 1978, but have degraded at accelerated rates since 1978. Thus economic growth has been the cause of accelerating human damage to China's coastal ecosystems. China's GDP per capita remains very low. Without strict conservation efforts, continuing economic growth will further degrade China's coastal ecosystems.

REGIONAL AIR-SEA INTERACTION (RASI) GAP WIND AND COASTAL UPWELLING EVENTS CLIMATOLOGY GULF OF PAPAGAYO, COSTA RICA V1

Data.gov (United States)

National Aeronautics and Space Administration — The Regional Air-Sea Interactions (RASI) Gap Wind and Coastal Upwelling Events Climatology Gulf of Papagayo, Costa Rica dataset was created using an automated...

Discriminating the biophysical impacts of coastal upwelling and mud banks along the southwest coast of India

Science.gov (United States)

Karnan, C.; Jyothibabu, R.; Arunpandi, N.; Jagadeesan, L.; Muraleedharan, K. R.; Pratihari, A. K.; Balachandran, K. K.; Naqvi, S. W. A.

2017-08-01

Coastal upwelling and mud banks are two oceanographic processes concurrently operating along certain stretches of the southwest (Kerala) coast of India during the Southwest Monsoon period (June-September), facilitating significant enhancement in plankton biomass. Mud banks have scientific and societal attention from time immemorial, predominantly due to the large fisheries associated with them. In this paper, for the first time, the specific biophysical roles of these oceanographic processes have been discriminated, based on a focused 18 weekly/fortnightly time-series study (April to September 2014) in a mud bank-upwelling area (off Alappuzha, southwest coast of India). In conjunction with standard hydrographical and satellite remote sensing data, we utilised a FlowCAM to track the biophysical linkage in terms of plankton composition abundance and size structure at three locations (M1, M2 and M3) in the study area. During the Pre-Southwest Monsoon (April-May), the entire study area was warmer with low nitrate concentration in the surface waters, which caused lower biomass of autotrophs compared to the Southwest Monsoon (June-September). By the onset of the Southwest Monsoon (June), drastic hydrographical transformations took place in the study domain due to the Coastal upwelling, reflected as the surfacing of significantly cool, high nutrient and hypoxic waters. Concurrently, mud bank formed at location M2 due to the presence of relatively high-suspended sediments in the region, creating a localised calm environment conducive for fishing activities. In response to the hydrographical transformations in the entire study area during the Southwest Monsoon, the autotrophic plankton biomass and size structure experienced significant change. The micro-autotrophs biomass that was low during the Pre-Southwest Monsoon (av. 0.33 ± 0.2 mgC L- 1 at surface and av. 0.07 ± 0.04 mgC L- 1 at subsurface) noticeably increased during the Southwest Monsoon (av. 1.6 ± 0.4 mgC L- 1 at

Microbial and biogeochemical responses to projected future nitrate enrichment in the California upwelling system

Directory of Open Access Journals (Sweden)

Katherine Rose Marie Mackey

2014-11-01

Full Text Available Coastal California is a dynamic upwelling region where nitrogen (N and iron (Fe can both limit productivity and influence biogeochemistry over different spatial and temporal scales. With global change, the flux of nitrate from upwelling is expected to increase over the next century, potentially driving additional oceanic regions toward Fe limitation. In this study we explored the effect of changes in Fe/N ratio on native phytoplankton from five currently Fe-replete sites near the major California upwelling centers at Bodega Bay and Monterey Bay using nutrient addition incubation experiments. Despite the high nitrate levels (13-30 M in the upwelled water, phytoplankton at three of the five sites showed increased growth when 10 M nitrate was added. None of the sites showed enhanced growth following addition of 10 nM Fe. Nitrate additions favored slow sinking single-celled diatoms over faster sinking chain-forming diatoms, suggesting that future increases in nitrate flux could affect carbon and silicate export and alter grazer populations. In particular, solitary cells of Cylindrotheca were more abundant than the toxin-producing genus Pseudonitzschia following nitrate addition. These responses suggest the biogeochemistry of coastal California could change in response to future increases in nitrate, and multiple stressors like ocean acidification and hypoxia may further result in ecosystem shifts.

Paradigms in the Recovery of Estuarine and Coastal Ecosystems

OpenAIRE

Duarte, Carlos M.; Borja, Ángel; Carstensen, Jacob; Elliott, Michael S.; Krause-Jensen, Dorte; Marbà, Núria

2015-01-01

© 2013, Coastal and Estuarine Research Federation. Following widespread deterioration of coastal ecosystems since the 1960s, current environmental policies demand ecosystem recovery and restoration. However, vague definitions of recovery and untested recovery paradigms complicate efficient stewardship of coastal ecosystems. We critically examine definitions of recovery and identify and test the implicit paradigms against well-documented cases studies based on a literature review. The study hi...

Spatial structure of the zooplankton community in the coastal upwelling system off central-southern Chile in spring 2004 as assessed by automated image analysis

Science.gov (United States)

Manríquez, Karen; Escribano, Ruben; Riquelme-Bugueño, Ramiro

2012-01-01

Size spectra of the mesozooplankton community was studied under the influence of coastal upwelling during austral spring 2004 in the coastal upwelling zone off central-southern Chile. Size spectra were derived from the ZooImage analysis of digitalized zooplankton samples obtained from the upper 200 m during a survey carried out under active upwelling (November 2004). An upwelling filament extended up to 180 km offshore, and the upper boundary of the oxygen minimum zone (1 mL O 2 L -1) varied between 20 m (nearshore) and 300 m depth (oceanic). The community descriptors (slope of the size spectra, size class index, abundance of size classes) were derived from the size spectra. Stepwise multiple regression analysis found significant correlations between these descriptors and oceanographic variables (temperature, dissolved oxygen, chlorophyll-a, OMZ depth). These data suggest an upwelling-dependent zooplankton distribution characterized by aggregations in a mid-shelf zone, where the log-normalized size spectra become flatter due to an increased abundance of larger size classes (>3 mm). In contrast, the inshore and offshore zones were dominated by small (zone coincided with moderate levels of chlorophyll-a (ca. 1 μg L -1) and the OMZ depth near 200 m. These spatial patterns and slopes of the size spectra however, were subjected to a significant day vs. night effect mostly explained by the diel vertical migration of the euphausiid Euphausia mucronata. This migration can descend below 200 m during the daylight, causing the larger size classes to disappear from the size spectrum and resulting in a steeper slope. Time-dependent effects must, therefore, be considered when examining the spatial patterns of zooplankton in coastal upwelling zones.

Rising synchrony controls western North American ecosystems

Science.gov (United States)

Bryan A. Black; Peter van der Sleen; Emanuele Di Lorenzo; Daniel Griffin; William J. Sydeman; Jason B. Dunham; Ryan R. Rykaczewski; Marisol García-Reyes; Mohammad Safeeq; Ivan Arismendi; Steven J. Bograd

2018-01-01

Along the western margin of North America, the winter expression of the North Pacific High (NPH) strongly influences interannual variability in coastal upwelling, storm track position, precipitation, and river discharge. Coherence among these factors induces covariance among physical and biological processes across adjacent marine and terrestrial ecosystems. Here, we...

Role of physical forcings and nutrient availability on the control of satellite-based chlorophyll a concentration in the coastal upwelling area of the Sicilian Channel

Directory of Open Access Journals (Sweden)

Bernardo Patti

2010-08-01

Full Text Available The northern sector of the Sicilian Channel is an area of favourable upwelling winds, which ought to support primary production. However, the values for primary production are low when compared with other Mediterranean areas and very low compared with the most biologically productive regions of the world’s oceans: California, the Canary Islands, Humboldt and Benguela. The aim of this study was to identify the main factors that limit phytoplankton biomass in the Sicilian Channel and modulate its monthly changes. We compared satellite-based estimates of chlorophyll a concentration in the Strait of Sicily with those observed in the four Eastern Boundary Upwelling Systems mentioned above and in other Mediterranean wind-induced coastal upwelling systems (the Alboran Sea, the Gulf of Lions and the Aegean Sea. Our results show that this low level of chlorophyll is mainly due to the low nutrient level in surface and sub-surface waters, independently of wind-induced upwelling intensity. Further, monthly changes in chlorophyll are mainly driven by the mixing of water column and wind-induced and/or circulation-related upwelling processes. Finally, primary production limitation due to the enhanced stratification processes resulting from the general warming trend of Mediterranean waters is not active over most of the coastal upwelling area off the southern Sicilian coast.

Assessment of Coastal Ecosystem Services for Conservation Strategies in South Korea.

Science.gov (United States)

Chung, Min Gon; Kang, Hojeong; Choi, Sung-Uk

2015-01-01

Despite the fact that scientific and political consideration for ecosystem services has dramatically increased over the past decade, few studies have focused on marine and coastal ecosystem services for conservation strategies. We used an ecosystem services approach to assess spatial distributions of habitat risks and four ecosystem services (coastal protection, carbon storage, recreation, and aesthetic quality), and explored the tradeoffs among them in coastal areas of South Korea. Additionally, we analyzed how the social and ecological characteristics in coastal areas interact with conservation and development policies by using this approach. We found strong negative associations between the habitat risks and ecosystem services (aquaculture, carbon storage, recreation, and aesthetic quality) across the coastal counties. Our results showed that the intensity of the habitat risks and the provision of ecosystem services were significantly different between reclamation-dominated and conservation-dominated counties, except for coastal vulnerability. A generalized linear model suggested that reclamation projects were dependent on economic efficiency, whereas demographic pressures and habitat conditions influenced the designation of protected areas at a county level. The ecosystem services approach provided guidelines to achieve both sustainable development and environment conservation. By using the approach, we can select the priority areas for developments while we can minimize the degradation of biodiversity and ecosystem services. As cultural ecosystem services are evenly distributed throughout coastal areas of South Korea, decision makers may employ them to improve the conditions of coastal wetlands outside of protected areas.

Assessment of Coastal Ecosystem Services for Conservation Strategies in South Korea

Science.gov (United States)

Chung, Min Gon; Kang, Hojeong; Choi, Sung-Uk

2015-01-01

Despite the fact that scientific and political consideration for ecosystem services has dramatically increased over the past decade, few studies have focused on marine and coastal ecosystem services for conservation strategies. We used an ecosystem services approach to assess spatial distributions of habitat risks and four ecosystem services (coastal protection, carbon storage, recreation, and aesthetic quality), and explored the tradeoffs among them in coastal areas of South Korea. Additionally, we analyzed how the social and ecological characteristics in coastal areas interact with conservation and development policies by using this approach. We found strong negative associations between the habitat risks and ecosystem services (aquaculture, carbon storage, recreation, and aesthetic quality) across the coastal counties. Our results showed that the intensity of the habitat risks and the provision of ecosystem services were significantly different between reclamation-dominated and conservation-dominated counties, except for coastal vulnerability. A generalized linear model suggested that reclamation projects were dependent on economic efficiency, whereas demographic pressures and habitat conditions influenced the designation of protected areas at a county level. The ecosystem services approach provided guidelines to achieve both sustainable development and environment conservation. By using the approach, we can select the priority areas for developments while we can minimize the degradation of biodiversity and ecosystem services. As cultural ecosystem services are evenly distributed throughout coastal areas of South Korea, decision makers may employ them to improve the conditions of coastal wetlands outside of protected areas. PMID:26221950

Dynamics of a "low-enrichment high-retention" upwelling center over the southern Senegal shelf

Science.gov (United States)

Ndoye, Siny; Capet, Xavier; Estrade, Philippe; Sow, Bamol; Machu, Eric; Brochier, Timothée.; Döring, Julian; Brehmer, Patrice

2017-05-01

Senegal is the southern tip of the Canary upwelling system. Its coastal ocean hosts an upwelling center which shapes sea surface temperatures between latitudes 12° and 15°N. Near this latter latitude, the Cape Verde headland and a sudden change in shelf cross-shore profile are major sources of heterogeneity in the southern Senegal upwelling sector (SSUS). SSUS dynamics is investigated by means of Regional Ocean Modeling System simulations. Configuration realism and resolution (Δx≈ 2 km) are sufficient to reproduce the SSUS frontal system. Our main focus is on the 3-D upwelling circulation which turns out to be profoundly different from 2-D theory: cold water injection onto the shelf and upwelling are strongly concentrated within a few tens of kilometers south of Cape Verde and largely arise from flow divergence in the alongshore direction; a significant fraction of the upwelled waters are retained nearshore over long distances while travelling southward under the influence of northerly winds. Another source of complexity, regional-scale alongshore pressure gradients, also contributes to the overall retention of upwelled waters over the shelf. Varying the degree of realism of atmospheric and oceanic forcings does not appreciably change these conclusions. This study sheds light on the dynamics and circulation underlying the recurrent sea surface temperature pattern observed during the upwelling season and offers new perspectives on the connections between the SSUS physical environment and its ecosystems. It also casts doubt on the validity of upwelling intensity estimations based on simple Ekman upwelling indices at such local scales.

Ecosystem services as a common language for coastal ecosystem-based management.

Science.gov (United States)

Granek, Elise F; Polasky, Stephen; Kappel, Carrie V; Reed, Denise J; Stoms, David M; Koch, Evamaria W; Kennedy, Chris J; Cramer, Lori A; Hacker, Sally D; Barbier, Edward B; Aswani, Shankar; Ruckelshaus, Mary; Perillo, Gerardo M E; Silliman, Brian R; Muthiga, Nyawira; Bael, David; Wolanski, Eric

2010-02-01

Ecosystem-based management is logistically and politically challenging because ecosystems are inherently complex and management decisions affect a multitude of groups. Coastal ecosystems, which lie at the interface between marine and terrestrial ecosystems and provide an array of ecosystem services to different groups, aptly illustrate these challenges. Successful ecosystem-based management of coastal ecosystems requires incorporating scientific information and the knowledge and views of interested parties into the decision-making process. Estimating the provision of ecosystem services under alternative management schemes offers a systematic way to incorporate biogeophysical and socioeconomic information and the views of individuals and groups in the policy and management process. Employing ecosystem services as a common language to improve the process of ecosystem-based management presents both benefits and difficulties. Benefits include a transparent method for assessing trade-offs associated with management alternatives, a common set of facts and common currency on which to base negotiations, and improved communication among groups with competing interests or differing worldviews. Yet challenges to this approach remain, including predicting how human interventions will affect ecosystems, how such changes will affect the provision of ecosystem services, and how changes in service provision will affect the welfare of different groups in society. In a case study from Puget Sound, Washington, we illustrate the potential of applying ecosystem services as a common language for ecosystem-based management.

Influences of riverine and upwelling waters on the coastal carbonate system off Central Chile and their ocean acidification implications

Science.gov (United States)

Vargas, Cristian A.; Contreras, Paulina Y.; Pérez, Claudia A.; Sobarzo, Marcus; Saldías, Gonzalo S.; Salisbury, Joe

2016-06-01

A combined data set, combining data from field campaigns and oceanographic cruises, was used to ascertain the influence of both river discharges and upwelling processes, covering spatial and temporal variation in dissolved inorganic carbon (DIC) and aragonite saturation state. This work was conducted in one of the most productive river-influenced upwelling areas in the South Pacific coasts (36°S). Additionally, further work was also conducted to ascertain the contribution of different DIC sources, influencing the dynamics of DIC along the land-ocean range. Six sampling campaigns were conducted across seven stations at the Biobío River basin, covering approximately 200 km. Three research cruises were undertaken simultaneously, covering the adjacent continental shelf, including 12 sampling stations for hydrographic measurements. Additionally, six stations were also sampled for chemical analyses, covering summer, winter, and spring conditions over 2010 and 2011. Our results evidenced that seaward extent of the river plume was more evident during the winter field campaign, when highest riverine DIC fluxes were observed. The carbonate system along the river-ocean continuum was very heterogeneous varying over spatial and temporal scales. High DIC and pCO2 were observed in river areas with larger anthropogenic effects. CO2 supersaturation at the river plume was observed during all campaigns due to the influence of low pH river waters in winter/spring and high-pCO2 upwelling waters in summer. δ13CDIC evidenced that main DIC sources along the river and river plume corresponded to the respiration of terrestrial organic matter. We have linked this natural process to the carbonate saturation on the adjacent river-influenced coastal area, suggesting that Ωaragonite undersaturation in surface/subsurface waters is largely modulated by the influence of both river discharge and coastal upwelling events in this productive coastal area. Conditions of low Ωaragonite might impact

Ecosystem engineering and biodiversity in coastal sediments: posing hypotheses

NARCIS (Netherlands)

Bouma, T.J.; Olenin, S.; Reise, K.; Ysebaert, T.

2009-01-01

Coastal sediments in sheltered temperate locations are strongly modified by ecosystem engineering species such as marsh plants, seagrass, and algae as well as by epibenthic and endobenthic invertebrates. These ecosystem engineers are shaping the coastal sea and landscape, control particulate and

Interactions between trophic levels in upwelling and non-upwelling regions during summer monsoon

Digital Repository Service at National Institute of Oceanography (India)

Malik, A; Fernandes, C.E.G.; Gonsalves, M.J.B.D.; Subina, N.S.; Mamatha, S.S.; Krishna, K.S.; Varik, S.; RituKumari; Gauns, M.; Cejoice, R.P.; Pandey, S.S.; Jineesh, V.K.; Kamaleson, A; Vijayan, V.; Mukherjee, I.; Subramanyan, S.; Nair, S.; Ingole, B.S.; LokaBharathi, P.A

Coastal upwelling is a regular phenomenon occurring along the southwest coast of India during summer monsoon (May–September). We hypothesize that there could be a shift in environmental parameters along with changes in the network of interactions...

Emergy evaluation of benthic ecosystems influenced by upwelling in northern Chile: Contributions of the ecosystems to the regional economy

Science.gov (United States)

Emergy evaluations of three benthic ecosystem networks found in Mejillones, Antofagasta and Tongoy Bays, located on the coast of northern Chile, were carried out with the intent of documenting the contributions of these coastal ecosystems to the economy. The productivity of these...

Nutrients, Recycling, and Biological Populations in Upwelling Ecosystems

Energy Technology Data Exchange (ETDEWEB)

Whitledge, T. E.

1980-01-01

Nutrient recycling has been studied in the upwelling areas of Baja California, Northwest Africa, and Peru. Regeneration by biological populations in these areas contributes significant quantities of recycled nitrogen which is utilized in productivity processes. Each area has a different combination of organisms which leads to differences in the relative contributions of zooplankton, nekton, or benthos to the nutrient cycles. Comparisons of ammonium regeneration rates of zooplankton and nekton-micronekton populations in the three upwelling areas show that zooplankton recycle relatively less nitrogen in the Baja California and Peru systems than nekton. In the Northwest Africa upwelling region, however, zooplankton, fish, and benthic inputs are all substantial. In recent years the Peruvian upwelling system has been altered with the decline of the anchoveta population and an increase in the importance of zooplankton in nutrient recycling. The distribution of recycled nitrogen (ammonium and urea) in transects across the shelf at 10°S and 15°S indicates that regeneration is relatively more important at 10°S in the region of the wide shelf. In both areas the distribution of ammonium and urea are not entirely coincident thereby indicating differences in their production and/or utilization.

Upwelling regions, the most fertile of the seas' habitats, are also ...

African Journals Online (AJOL)

spamer

apply to dinoflagellate bloom events in coastal upwelling systems. * Graduate School of ..... exclusive of coccolithophorids (Smayda 1997b). Group. Daily growth rates ..... route taken partly dependent on the duration of the upwelling relaxation ...

Spatial and temporal variability in coccolithophore abundance and distribution in the NW Iberian coastal upwelling system

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B. Ausín

2018-01-01

Full Text Available A systematic investigation of the spatial and temporal variability in coccolithophore abundance and distribution through the water column of the NW Iberian coastal upwelling system was performed. From July 2011 to June 2012, monthly sampling at various water depths was conducted at two parallel stations located at 42° N. Total coccosphere abundance was higher at the outer-shelf station, where warmer, nutrient-depleted waters favoured coccolithophore rather than phytoplanktonic diatom blooms, which are known to dominate the inner-shelf location. In seasonal terms, higher coccosphere and coccolith abundances were registered at both stations during upwelling seasons, coinciding with high irradiance levels. This was typically in conjunction with stratified, nutrient-poor conditions (i.e. relaxing upwelling conditions. However, it also occurred during some upwelling events of colder, nutrient-rich subsurface waters onto the continental shelf. Minimum abundances were generally found during downwelling periods, with unexpectedly high coccolith abundance registered in subsurface waters at the inner-shelf station. This finding can only be explained if strong storms during these downwelling periods favoured resuspension processes, thus remobilizing deposited coccoliths from surface sediments, and hence hampering the identification of autochthonous coccolithophore community structure. At both locations, the major coccolithophore assemblages were dominated by Emiliania huxleyi, small Gephyrocapsa group, Gephyrocapsa oceanica, Florisphaera profunda, Syracosphaera spp., Coronosphaera mediterranea, and Calcidiscus leptoporus. Ecological preferences of the different taxa were assessed by exploring the relationships between environmental conditions and temporal and vertical variability in coccosphere abundance. These findings provide relevant information for the use of fossil coccolith assemblages in marine sediment records, in order to infer past

Spatial and temporal variability in coccolithophore abundance and distribution in the NW Iberian coastal upwelling system

Science.gov (United States)

Ausín, Blanca; Zúñiga, Diana; Flores, Jose A.; Cavaleiro, Catarina; Froján, María; Villacieros-Robineau, Nicolás; Alonso-Pérez, Fernando; Arbones, Belén; Santos, Celia; de la Granda, Francisco; Castro, Carmen G.; Abrantes, Fátima; Eglinton, Timothy I.; Salgueiro, Emilia

2018-01-01

A systematic investigation of the spatial and temporal variability in coccolithophore abundance and distribution through the water column of the NW Iberian coastal upwelling system was performed. From July 2011 to June 2012, monthly sampling at various water depths was conducted at two parallel stations located at 42° N. Total coccosphere abundance was higher at the outer-shelf station, where warmer, nutrient-depleted waters favoured coccolithophore rather than phytoplanktonic diatom blooms, which are known to dominate the inner-shelf location. In seasonal terms, higher coccosphere and coccolith abundances were registered at both stations during upwelling seasons, coinciding with high irradiance levels. This was typically in conjunction with stratified, nutrient-poor conditions (i.e. relaxing upwelling conditions). However, it also occurred during some upwelling events of colder, nutrient-rich subsurface waters onto the continental shelf. Minimum abundances were generally found during downwelling periods, with unexpectedly high coccolith abundance registered in subsurface waters at the inner-shelf station. This finding can only be explained if strong storms during these downwelling periods favoured resuspension processes, thus remobilizing deposited coccoliths from surface sediments, and hence hampering the identification of autochthonous coccolithophore community structure. At both locations, the major coccolithophore assemblages were dominated by Emiliania huxleyi, small Gephyrocapsa group, Gephyrocapsa oceanica, Florisphaera profunda, Syracosphaera spp., Coronosphaera mediterranea, and Calcidiscus leptoporus. Ecological preferences of the different taxa were assessed by exploring the relationships between environmental conditions and temporal and vertical variability in coccosphere abundance. These findings provide relevant information for the use of fossil coccolith assemblages in marine sediment records, in order to infer past environmental conditions, of

Vertical segregation among pathways mediating nitrogen loss (N2 and N2O production) across the oxygen gradient in a coastal upwelling ecosystem

Science.gov (United States)

Galán, Alexander; Thamdrup, Bo; Saldías, Gonzalo S.; Farías, Laura

2017-10-01

The upwelling system off central Chile (36.5° S) is seasonally subjected to oxygen (O2)-deficient waters, with a strong vertical gradient in O2 (from oxic to anoxic conditions) that spans a few metres (30-50 m interval) over the shelf. This condition inhibits and/or stimulates processes involved in nitrogen (N) removal (e.g. anammox, denitrification, and nitrification). During austral spring (September 2013) and summer (January 2014), the main pathways involved in N loss and its speciation, in the form of N2 and/or N2O, were studied using 15N-tracer incubations, inhibitor assays, and the natural abundance of nitrate isotopes along with hydrographic information. Incubations were developed using water retrieved from the oxycline (25 m depth) and bottom waters (85 m depth) over the continental shelf off Concepción, Chile. Results of 15N-labelled incubations revealed higher N removal activity during the austral summer, with denitrification as the dominant N2-producing pathway, which occurred together with anammox at all times. Interestingly, in both spring and summer maximum potential N removal rates were observed in the oxycline, where a greater availability of oxygen was observed (maximum O2 fluctuation between 270 and 40 µmol L-1) relative to the hypoxic bottom waters ( multiple N-cycling processes are modulating the isotopic nitrate composition over the shelf off central Chile during spring and summer. N removal processes in this coastal system appear to be related to the availability and distribution of oxygen and particles, which are a source of organic matter and the fuel for the production of other electron donors (i.e. ammonium) and acceptors (i.e. nitrate and nitrite) after its remineralization. These results highlight the links between several pathways involved in N loss. They also establish that different mechanisms supported by alternative N substrates are responsible for substantial accumulation of N2O, which are frequently observed as hotspots in the

Hierarchical Synthesis of Coastal Ecosystem Health Indicators at Karimunjawa National Marine Park

Science.gov (United States)

Danu Prasetya, Johan; Ambariyanto; Supriharyono; Purwanti, Frida

2018-02-01

The coastal ecosystem of Karimunjawa National Marine Park (KNMP) is facing various pressures, including from human activity. Monitoring the health condition of coastal ecosystems periodically is needed as an evaluation of the ecosystem condition. Systematic and consistent indicators are needed in monitoring of coastal ecosystem health. This paper presents hierarchical synthesis of coastal ecosystem health indicators using Analytic Hierarchy Process (AHP) method. Hierarchical synthesis is obtained from process of weighting by paired comparison based on expert judgments. The variables of coastal ecosystem health indicators in this synthesis consist of 3 level of variable, i.e. main variable, sub-variable and operational variable. As a result of assessment, coastal ecosystem health indicators consist of 3 main variables, i.e. State of Ecosystem, Pressure and Management. Main variables State of Ecosystem and Management obtain the same value i.e. 0.400, while Pressure value was 0.200. Each main variable consist of several sub-variable, i.e. coral reef, reef fish, mangrove and seagrass for State of Ecosystem; fisheries and marine tourism activity for Pressure; planning and regulation, institutional and also infrastructure and financing for Management. The highest value of sub-variable of main variable State of Ecosystem, Pressure and Management were coral reef (0.186); marine tourism pressure (0.133) and institutional (0.171), respectively. The highest value of operational variable of main variable State of Ecosystem, Pressure and Management were percent of coral cover (0.058), marine tourism pressure (0.133) and presence of zonation plan, regulation also socialization of monitoring program (0.53), respectively. Potential pressure from marine tourism activity is the variable that most affect the health of the ecosystem. The results of this research suggest that there is a need to develop stronger conservation strategies to facing with pressures from marine tourism

Upwelling characteristics in the Gulf of Finland (Baltic Sea) as revealed by Ferrybox measurements in 2007-2013

Science.gov (United States)

Kikas, Villu; Lips, Urmas

2016-07-01

Ferrybox measurements have been carried out between Tallinn and Helsinki in the Gulf of Finland (Baltic Sea) on a regular basis since 1997. The system measures autonomously water temperature, salinity, chlorophyll a fluorescence and turbidity and takes water samples for further analyses at a predefined time interval. We aimed to show how the Ferrybox technology could be used to study the coastal upwelling events in the Gulf of Finland. Based on the introduced upwelling index and related criteria, 33 coastal upwelling events were identified in May-September 2007-2013. The number of events, as well as the frequency of their occurrence and intensity expressed as a sum of daily average temperature deviations in the 20 km wide coastal area, were almost equal near the northern and southern coasts. Nevertheless, the wind impulse, which was needed to generate upwelling events of similar intensity, differed between the northern and southern coastal areas. It is suggested that the general thermohaline structure adapted to the prevailing forcing and the estuarine character of the basin weaken the upwelling created by the westerly to southwesterly (up-estuary) winds and strengthen the upwelling created by the easterly to northeasterly (down-estuary) winds. Two types of upwelling events were identified - one characterized by a strong temperature front and the other revealing gradual decrease in temperature from the open sea to the coastal area, with maximum temperature deviation close to the shore.

Remote sensing and aerial photography for delineation and management of coastal ecosystems

Digital Repository Service at National Institute of Oceanography (India)

Jagtap, T.G.

sensing data. may provide necessary information to the planners and researchers. interested in the 11 .. coastal ecosystems. Mismanagement or lack of management of coastal zones may result in the loss of marine ecosystems, influencing erosion and the sea..., topographic maps and other resources. The effective management and research of coastal zones, require information on coastal landforms, wetlands, shoreline changes, sediment and current pattern, which can easily be obtained from the satellite data. Coastal...

Coastal High-resolution Observations and Remote Sensing of Ecosystems (C-HORSE)

Science.gov (United States)

Guild, Liane

2016-01-01

Coastal benthic marine ecosystems, such as coral reefs, seagrass beds, and kelp forests are highly productive as well as ecologically and commercially important resources. These systems are vulnerable to degraded water quality due to coastal development, terrestrial run-off, and harmful algal blooms. Measurements of these features are important for understanding linkages with land-based sources of pollution and impacts to coastal ecosystems. Challenges for accurate remote sensing of coastal benthic (shallow water) ecosystems and water quality are complicated by atmospheric scattering/absorption (approximately 80+% of the signal), sun glint from the sea surface, and water column scattering (e.g., turbidity). Further, sensor challenges related to signal to noise (SNR) over optically dark targets as well as insufficient radiometric calibration thwart the value of coastal remotely-sensed data. Atmospheric correction of satellite and airborne remotely-sensed radiance data is crucial for deriving accurate water-leaving radiance in coastal waters. C-HORSE seeks to optimize coastal remote sensing measurements by using a novel airborne instrument suite that will bridge calibration, validation, and research capabilities of bio-optical measurements from the sea to the high altitude remote sensing platform. The primary goal of C-HORSE is to facilitate enhanced optical observations of coastal ecosystems using state of the art portable microradiometers with 19 targeted spectral channels and flight planning to optimize measurements further supporting current and future remote sensing missions.

Intensification of Chile-Peru upwelling under climate change: diagnosing the impact of natural and anthropogenic forcing from the IPSL-CM5 model.

Science.gov (United States)

Jebri, B.; Khodri, M.; Gastineau, G.; Echevin, V.; Thiria, S.

2017-12-01

Upwelling is critical to the biological production, acidification, and deoxygenation of the ocean's major eastern boundary current ecosystems. A conceptual hypothesis suggests that the winds that favour coastal upwelling intensify with anthropogenic global warming due to increased land-sea temperature contrast. We examine this hypothesis for the dynamics of the Peru-Chile upwelling using a set of four large ensembles of coupled, ocean-atmosphere model simulations with the IPSL model covering the 1940-2014 period. In one large ensemble we prescribe the standard CMIP5 greenhouse gas (GHG) concentrations, anthropogenic aerosol, ozone and volcanic forcings, following the historical experiments through 2005 and RCP8.5 from 2006-2014, while the other ensembles consider separately the GHG, ozone and volcanic forcings. We find evidence for intensification of upwelling-favourable winds with however little evidence of atmospheric pressure gradients in response to increasing land-sea temperature differences. Our analyses reveal poleward migration and intensification of the South Pacific Anticyclone near poleward boundaries of climatological Peruvian and Chilean upwelling zones. This contribution further investigates the physical mechanisms for the Peru-Chile upwelling intensification and the relative role of natural and anthropogenic forcings.

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.

Shift in the species composition of the diatom community in the eutrophic Mauritanian coastal upwelling: Results from a multi-year sediment trap experiment (2003-2010)

Science.gov (United States)

Romero, Oscar E.; Fischer, Gerhard

2017-12-01

A multiannual, continuous sediment trap experiment was conducted at the mooring site CBeu (Cape Blanc eutrophic, ca. 20 °N, ca. 18 °W; trap depth = 1256-1296 m) in the high-productive Mauritanian coastal upwelling. Here we present fluxes and the species-specific composition of the diatom assemblage, and fluxes of biogenic silica (BSi, opal) and total organic carbon (TOC) for the time interval June 2003-Feb 2010. Flux ranges of studied parameters are (i) total diatoms = 1.2 ∗ 108-4.7 ∗ 104 valves m-2 d-1 (average = 5.9 × 106 valves ± 1.4 × 107); (ii) BSi = 296-0.5 mg m-2 d-1 (average = 41.1 ± 53.5 mg m-2 d-1), and (iii) TOC = 97-1 mg m-2 d-1 (average = 20.5 ± 17.8 mg m-2 d-1). Throughout the experiment, the overall good match of total diatom, BSi and TOC fluxes is reasonably consistent and reflects well the temporal occurrence of the main Mauritanian upwelling season. Spring and summer are the most favorable seasons for diatom production and sedimentation: out of the recorded 14 diatom maxima of different magnitude, six occurred in spring and four in summer. The diverse diatom community at site CBeu is composed of four main assemblages: benthic, coastal upwelling, coastal planktonic and open-ocean diatoms, reflecting different productivity conditions and water masses. A striking feature of the temporal variability of the diatom populations is the persistent pattern of seasonal groups' contribution: benthic and coastal upwelling taxa dominated during the main upwelling season in spring, while open-ocean diatoms were more abundant in fall and winter, when the upper water column becomes stratified, upwelling relaxes and productivity decreases. The relative abundance of benthic diatoms strongly increased after 2006, yet their spring-summer contribution remained high until the end of the trap experiment. The occurrence of large populations of benthic diatoms at the hemipelagic CBeu site is interpreted to indicate transport from shallow waters via nepheloid

Determination of the Anthropogenic Carbon Signal to the Total Change in Dissolved Carbon in the Coastal Upwelling Region Along the Washington-Oregon-California Continental Margin

Science.gov (United States)

Feely, R. A.

2016-02-01

The continental shelf region off the Washington-Oregon-California coast is seasonally exposed to water with a low aragonite saturation state by coastal upwelling of CO2-rich waters. To date, the spatial and temporal distribution of anthropogenic CO2 (Canthro) contribution to the CO2-rich waters is largely unknown. Here we use an adaptation of the linear regression approach described in Feely et al (2008) along with the GO-SHIP Repeat Hydrography data sets from the northeast Pacific to establish an annually updated relationship between Canthro and potential density. This relationship was then used with the NOAA Ocean Acidification Program west coast cruise data sets from 2007, 2011, 2012 and 2013 to determine the spatial variations of Canthro in the upwelled water. Our results show large spatial differences in Canthro in surface waters along the coast with the lowest surface values (40-45 µmol kg-1) in strong upwelling regions of off northern California and southern Oregon and higher values (50-70 µmol kg-1) to the north and south. Canthro contributes an average of about 70% of the increased amount of dissolved inorganic carbon in the upwelled waters at the surface. In contrast, at 50 m the Canthro contribution is approximately 31% and at 100 m it averages about 16%. The remaining contributions are primarily due to respiration processes in the water that was upwelled and transported to coastal regions or underwent respiration processes that occurred locally during the course of the upwelling season. The uptake of Canthro has caused the aragonite saturation horizon to shoal by approximately 30-50 m since preindustrial period so that the undersaturated waters are well within the regions that affect the biological communities on the continental shelf.

Causes and consequences of ecosystem service regionalization in a coastal suburban watershed

Science.gov (United States)

Wollheim, Wilfred M.; Mark B. Green,; Pellerin, Brian A.; Morse, Nathaniel B.; Hopkinson, Charles S.

2015-01-01

The demand for ecosystem services and the ability of natural ecosystems to provide those services evolve over time as population, land use, and management practices change. Regionalization of ecosystem service activity, or the expansion of the area providing ecosystem services to a population, is a common response in densely populated coastal regions, with important consequences for watershed water and nitrogen (N) fluxes to the coastal zone. We link biophysical and historical information to explore the causes and consequences of change in ecosystem service activity—focusing on water provisioning and N regulation—from 1850 to 2010 in a coastal suburban watershed, the Ipswich River watershed in northeastern Massachusetts, USA. Net interbasin water transfers started in the late 1800s due to regionalization of water supply for use by larger populations living outside the Ipswich watershed boundaries, reaching a peak in the mid-1980s. Over much of the twentieth century, about 20 % of river runoff was diverted from reaching the estuary, with greater proportions during drought years. Ongoing regionalization of water supply has contributed to recent declines in diversions, influenced by socioecological feedbacks resulting from the river drying and fish kills. Similarly, the N budget has been greatly perturbed since the suburban era began in the 1950s due to food and lawn fertilizer imports and human waste release. However, natural ecosystems are able to remove most of this anthropogenic N, mitigating impacts on the coastal zone. We propose a conceptual model whereby the amount and type of ecosystem services provided by coastal watersheds in urban regions expand and contract over time as regional population expands and ecosystem services are regionalized. We hypothesize that suburban watersheds can be hotspots of ecosystem service sources because they retain sufficient ecosystem function to still produce services that meet increasing demand from the local population

Temporal development of coastal ecosystems in the Baltic Sea over the past two decades

DEFF Research Database (Denmark)

Olsson, Jens; Tomczak, Maciej; Ojaveer, Henn

2015-01-01

Coastal areas are among the most biologically productive aquatic systems worldwide, but face strong and variable anthropogenic pressures. Few studies have, however, addressed the temporal development of coastal ecosystems in an integrated context. This study represents an assessment of the develo...... in the capacity of currently available monitoring data to support integrated assessments and the implementation of an integrated ecosystem-based approach to the management of the Baltic Sea coastal ecosystems......Coastal areas are among the most biologically productive aquatic systems worldwide, but face strong and variable anthropogenic pressures. Few studies have, however, addressed the temporal development of coastal ecosystems in an integrated context. This study represents an assessment...

Contribution of changes in opal productivity and nutrient distribution in the coastal upwelling systems to Late Pliocene/Early Pleistocene climate cooling

Directory of Open Access Journals (Sweden)

J. Etourneau

2012-09-01

Full Text Available The global Late Pliocene/Early Pleistocene cooling (~3.0–2.0 million years ago – Ma concurred with extremely high diatom and biogenic opal production in most of the major coastal upwelling regions. This phenomenon was particularly pronounced in the Benguela upwelling system (BUS, off Namibia, where it is known as the Matuyama Diatom Maximum (MDM. Our study focuses on a new diatom silicon isotope (δ³⁰Si record covering the MDM in the BUS. Unexpectedly, the variations in δ³⁰Si signal follow biogenic opal content, whereby the highest δ³⁰Si values correspond to the highest biogenic opal content. We interpret the higher δ³⁰Si values during the MDM as a result of a stronger degree of silicate utilisation in the surface waters caused by high productivity of mat-forming diatom species. This was most likely promoted by weak upwelling intensity dominating the BUS during the Late Pliocene/Early Pleistocene cooling combined with a large silicate supply derived from a strong Southern Ocean nutrient leakage responding to the expansion of Antarctic ice cover and the resulting stratification of the polar ocean 3.0–2.7 Ma ago. A similar scenario is hypothesized for other major coastal upwelling systems (e.g. off California during this time interval, suggesting that the efficiency of the biological carbon pump was probably sufficiently enhanced in these regions during the MDM to have significantly increased the transport of atmospheric CO₂ to the deep ocean. In addition, the coeval extension of the area of surface water stratification in both the Southern Ocean and the North Pacific, which decreased CO₂ release to the atmosphere, led to further enhanced atmospheric CO₂ drawn-down and thus contributed significantly to Late Pliocene/Early Pleistocene cooling.

THE INNOVATIVE POLICY OPTIONS FOR COASTAL FISHERIES ECONOMIC DEVELOPMENT: A CASE OF KWANDANG BAY COASTAL ECOSYSTEM

Directory of Open Access Journals (Sweden)

Noel Taylor Moore

2017-07-01

Full Text Available Socio-environmental problems, such as climate change, pollution and habitat destruction, present serious challenges for fisheries economic development. The integration of interventions or investments within a coastal marine ecosystem, a defined spatial area, is considered important in the economic development of local communities leading to the planned outcomes of livelihoods, food security and conservation The coastal marine ecosystem, is the provider of products and services to the local economy adjacent to the ecosystem where the benefit flows, within that area, are interconnected. The roles of science, technology and innovation (STI are an integral part of these multi-dimensional interventions. Hence the need for an integrated approach for these interventions by government and/or through donor funded projects to enhance economic development of coastal communities. The policy framework proposed is therefore an STI perspective of the links between these intervention and investment options, based on a ‘fisheries economic development Hub’ (Hub and discussed using the multi-level perspective (MLP. The policy innovation proposal suggests an implementation strategy of a pilot project and analyses the selection and implications of a potential Indonesian site for the application of the Hub. This paper aims to introduce the MLP into the framework of coastal community-based fisheries economic development.   Key words: policy innovation. coastal marine ecosystem, fisheries economic development Hub, value chains, multi-level perspective (MLP

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.

Assessment of coastal management options by means of multilayered ecosystem models

Science.gov (United States)

Nobre, Ana M.; Ferreira, João G.; Nunes, João P.; Yan, Xiaojun; Bricker, Suzanne; Corner, Richard; Groom, Steve; Gu, Haifeng; Hawkins, Anthony J. S.; Hutson, Rory; Lan, Dongzhao; Silva, João D. Lencart e.; Pascoe, Philip; Telfer, Trevor; Zhang, Xuelei; Zhu, Mingyuan

2010-03-01

This paper presents a multilayered ecosystem modelling approach that combines the simulation of the biogeochemistry of a coastal ecosystem with the simulation of the main forcing functions, such as catchment loading and aquaculture activities. This approach was developed as a tool for sustainable management of coastal ecosystems. A key feature is to simulate management scenarios that account for changes in multiple uses and enable assessment of cumulative impacts of coastal activities. The model was applied to a coastal zone in China with large aquaculture production and multiple catchment uses, and where management efforts to improve water quality are under way. Development scenarios designed in conjunction with local managers and aquaculture producers include the reduction of fish cages and treatment of wastewater. Despite the reduction in nutrient loading simulated in three different scenarios, inorganic nutrient concentrations in the bay were predicted to exceed the thresholds for poor quality defined by Chinese seawater quality legislation. For all scenarios there is still a Moderate High to High nutrient loading from the catchment, so further reductions might be enacted, together with additional decreases in fish cage culture. The model predicts that overall, shellfish production decreases by 10%-28% using any of these development scenarios, principally because shellfish growth is being sustained by the substances to be reduced for improvement of water quality. The model outcomes indicate that this may be counteracted by zoning of shellfish aquaculture at the ecosystem level in order to optimize trade-offs between productivity and environmental effects. The present case study exemplifies the value of multilayered ecosystem modelling as a tool for Integrated Coastal Zone Management and for the adoption of ecosystem approaches for marine resource management. This modelling approach can be applied worldwide, and may be particularly useful for the application of

An integrated approach to manage coastal ecosystems and prevent marine pollution effects

Science.gov (United States)

Marcelli, Marco; Bonamano, Simone; Carli, Filippo Maria; Giovacchini, Monica; Madonia, Alice; Mancini, Emanuele; Molino, Chiara; Piermattei, Viviana; Manfredi Frattarelli, Francesco

2016-04-01

This work focuses an integrated approach based on Sea-Use-Map (SUM), backed by a permanent monitoring system (C-CEMS-Civitavecchia Coastal Environmental Monitoring System). This tool supports the management of the marine coastal area, contributing substantially to ecosystem benefits evaluation and to minimize pollution impacts. Within the Blue Growth strategy, the protection of marine ecosystems is considered a priority for the sustainable growth of marine and maritime sectors. To face this issue, the European MSP and MSFD directives (2014/89/EU; 2008/56/EC) strongly promote the adoption of an ecosystem-based approach, paying particular attention to the support of monitoring networks that use L-TER (long-term ecological research) observations and integrate multi-disciplinary data sets. Although not largely used in Europe yet, the Environmental Sensitivity Index (ESI), developed in 1979 by NOAA (and promoted by IMO in 2010), can be considered an excellent example of ecosystem-based approach to reduce the environmental consequences of an oil spill event in a coastal area. SUM is an ecosystem oriented cartographic tool specifically designed to support the sustainable management of the coastal areas, such as the selection of the best sites for the introduction of new uses or the identification of the coastal areas subjected to potential impacts. It also enables a rapid evaluation of the benefits produced by marine areas as well as of their anthropogenic disturbance. SUM integrates C-CEMS dataset, geomorphological and ecological features and knowledge on the coastal and maritime space uses. The SUM appliance allowed to obtain relevant operational results in the Civitavecchia coastal area (Latium, Italy), characterized by high variability of marine and coastal environments, historical heritage and affected by the presence of a big harbour, relevant industrial infrastructures, and touristic features. In particular, the valuation of marine ecosystem services based on

Genetic Enhancement of Coastal Ecosystem (abstract)

International Nuclear Information System (INIS)

Parida, A.

2005-01-01

Coastal and marine areas contain some of the world's most diverse and productive biological systems. They are sensitive to human activities, impact and interventions. Pressures on these systems are growing more intense. As rapid development and population growth continue in coastal areas increasing demands are expected on natural resources and on remaining natural habitats along the coasts. The problem is more serious in Indian context that has a 7,500 km long coastline and is facing increasing soil erosion and water pollution. The prospects of sea level rise, expected to be in the order of 8-29 cm due to the global warming by 2025, necessitates immediate measures to foster the sustainable and equitable management of the coastal wetland ecosystems. Salinity is a significant limiting factor to agricultural productivity affecting about 9 x 10/sup 8/ha, worldwide. About one-third of all irrigated land is affected by salt due to secondary salinisation and it is estimated that 50% of the arable lands will be salinised by the year 2050. The problem of salinity is most acute in the coastal regions affecting the productivity of the agricultural system. Improving or maintaining yield potential of the crops under increased salinisation is of greater significance for the future. With a view to identify and isolate novel genetic combinations offering resistance to coastal salinity, MSSRF has initiated work on mangrove species. Mangroves are salt tolerant plant communities occupying the coastal estuarine regions of the tropics. They serve as a vital link between terrestrial and aquatic ecosystems and provide livelihood and ecological security for the coastal communities. MSSRF is the first institution worldwide to have undertaken modern molecular marker based analysis of mangroves. These studies have provided substantial information for developing unambiguous identification systems for individual species, elucidating nature and extent of genetic diversity at intra- and inter

Regulation of bacterial sulfate reduction and hydrogen sulfide fluxes in the central Namibian coastal upwelling zone

DEFF Research Database (Denmark)

Bruchert, V.; Jørgensen, BB; Neumann, K.

2003-01-01

The coastal upwelling system off central Namibia is one of the most productive regions of the oceans and is characterized by frequently occurring shelf anoxia with severe effects for the benthic life and fisheries. We present data on water column dissolved oxygen, sulfide, nitrate and nitrite, pore......-depleted bottom waters, the oxygen minimum zone on the continental slope, and the lower continental slope below the oxygen minimum zone. High concentrations of dissolved sulfide, up to 22 mM, in the near-surface sediments of the inner shelf result from extremely high rates of bacterial sulfate reduction...

Study on the cumulative impact of reclamation activities on ecosystem health in coastal waters.

Science.gov (United States)

Shen, Chengcheng; Shi, Honghua; Zheng, Wei; Li, Fen; Peng, Shitao; Ding, Dewen

2016-02-15

The purpose of this study is to develop feasible tools to investigate the cumulative impact of reclamations on coastal ecosystem health, so that the strategies of ecosystem-based management can be applied in the coastal zone. An indicator system and model were proposed to assess the cumulative impact synthetically. Two coastal water bodies, namely Laizhou Bay (LZB) and Tianjin coastal waters (TCW), in the Bohai Sea of China were studied and compared, each in a different phase of reclamations. Case studies showed that the indicator scores of coastal ecosystem health in LZB and TCW were 0.75 and 0.68 out of 1.0, respectively. It can be concluded that coastal reclamations have a historically cumulative effect on benthic environment, whose degree is larger than that on aquatic environment. The ecosystem-based management of coastal reclamations should emphasize the spatially and industrially intensive layout. Copyright © 2015 Elsevier Ltd. All rights reserved.

Linking the Modern and Recent Record of Cabo Frio Upwelling with Local Climate and Biogeochemical Processes in Hypersaline Coastal Lagoons, Região dos Lagos, Rio de Janeiro, Brazil

Science.gov (United States)

McKenzie, J. A.; Nascimento, G. S.; Albuquerque, A. L.; Belem, A. L.; Carreira, R.; Eglinton, T. I.; Vasconcelos, C.

2015-12-01

A unique marine and lagoonal system along the coast east of Rio de Janeiro is being investigated to understand the impact of climatic variability on the South Atlantic carbon cycle and biomineralisation processes involved in carbonate precipitation in the hypersaline coastal lagoons. The region is dominated by a semi-arid microclimate attributed to the local coastal upwelling phenomenon near Cabo Frio. The intensity of the upwelling affects the hydrology of the annual water and biogeochemical cycles in the lagoons, as well as biogeochemical signals of environmental change recorded in both onshore and offshore sediments. Preliminary results of δ18O and δD values of water samples collected monthly in Lagoa Vermelha and Brejo do Espinho from 2011 to 2014 show lower values for waters corresponding to the wet season, reflecting increased input of meteoric water. The higher values for waters collected during the dry season reflect the greater amount of evaporation with increased seasonal aridity. Radiocarbon dating of Holocene marine and lagoonal cores indicates that Mg-carbonate precipitation in the lagoons is associated with high evaporation. Modern field observations for the last 3 years suggest that the amount of carbonate precipitation is correlated with evaporitic conditions associated with the upwelling phenomenon. A calibration study of hydrogen isotopic fractionation in the modern lagoons is underway to define a relationship between δDlipid of suspended particles and δDwater of associated water. This isotopic relationship will be applied to material obtained in cores from the lagoons. Offshore cores will be studied using well-tested paleotemperature proxies to evaluate the intensity of the upwelling during the Holocene. In summary, linking the coastal upwelling with the lagoonal hydrology has the potential to furnish important insights about the relationship between the local climate and paleoceanographic circulation associated with the regional carbon cycle.

Sustainability Of Coastal Fringe Ecosystems Against Anthropogenic Chemical Stressors

Science.gov (United States)

Plant-dominated coastal ecosystems provide least 21 ecological services including shoreline protection, contaminant removal and nursery and breeding habitat for biota. The value of these ecological services is as great as $28000/h. These ecosystems which include intertidal wetl...

The need for ecosystem-based coastal planning in Trabzon city

OpenAIRE

Mustafa Dihkan; Nilgün Güneroğlu; Abdülaziz Güneroğlu; Fevzi Karslı

2017-01-01

Coastal urbanization problem was emanated from willingness of coastal living. Urban sprawl is one of the most important coastal problems in Turkey as it is in Trabzon city which is known for its natural and historical assets. In order to ensure the sustainability and ecological continuity of the city, an ecosystem based coastal planning is an issue of high priority. Protection and usage balance of the coastal areas could also ensure transition of the natural values to future gener...

On an upwelling front, propagation of upwelling and vertical velocity in the eastern Arabian sea during monsoon, 1987

Digital Repository Service at National Institute of Oceanography (India)

Antony, M.K.; Unnikrishnan, A.S.

A coastal upwelling front parallel to the coast and identifiable upto a depth of 75 m was observed between 12.5 and 16 degrees N along the eastern Arabian Sea in September, 1987 from closely spaced digital BT data. With a north-south slope...

Organic carbon sedimentation rates in Asian mangrove coastal ecosystems estimated by 210PB chronology

International Nuclear Information System (INIS)

Tateda, Y.; Wattayakorn, G.; Nhan, D.D.; Kasuya, Y.

2004-01-01

Organic carbon balance estimation of mangrove coastal ecosystem is important for understanding of Asian coastal carbon budget/flux calculation in global carbon cycle modelling which is powerful tool for the prediction of future greenhouse gas effect and evaluation of countermeasure preference. Especially, the organic carbon accumulation rate in mangrove ecosystem was reported to be important sink of carbon as well as that in boreal peat accumulation. For the estimation of 10 3 years scale organic carbon accumulation rates in mangrove coastal ecosystems, 14 C was used as long term chronological tracer, being useful in pristine mangrove forest reserve area. While in case of mangrove plantation of in coastal area, the 210 Pb is suitable for the estimation of decades scale estimation by its half-life. Though it has possibility of bio-/physical- turbation effect in applying 210 Pb chronology that is offset in case of 10 3 years scale estimation, especially in Asian mangrove ecosystem where the anthropogenic physical turbation by coastal fishery is vigorous.In this paper, we studied the organic carbon and 210 Pb accumulation rates in subtropical mangrove coastal ecosystems in Japan, Vietnam and Thailand with 7 Be analyses to make sure the negligible effect of above turbation effects on organic carbon accumulation. We finally concluded that 210 Pb was applicable to estimate organic carbon accumulation rates in these ecosystems even though the physical-/bio-turbation is expected. The measured organic carbon accumulation rates using 210 Pb in mangrove coastal ecosystems of Japan, Vietnam and Thailand were 0.067 4.0 t-C ha -1 y -1 . (author)

Ocean Drilling Program Leg 112, Peru continental margin: Part 2, Sedimentary history and diagenesis in a coastal upwelling environment

Science.gov (United States)

Suess, E.; von Huene, R.

1988-10-01

On the shelf and upper slope off Peru the signal of coastal upwelling productivity and bottom-water oxygen is well preserved in alternately laminated and bioturbated diatomaceous Quaternary sediments. Global sea-level fluctuations are the ultimate cause for these cyclic facies changes. During late Miocene time, coastal upwelling was about 100 km west of the present centers, along the edge of an emergent structure that subsequently subsided to form the modern slope. The sediments are rich in organic carbon, and intense microbially mediated decomposition of organic matter is evident in sulfate reduction and methanogenesis. These processes are accompanied by the formation of diagenetic carbonates, mostly Ca-rich dolomites and Mg-calcites. The downhole isotopic signatures of these carbonate cements display distinct successions that reflect the vertical evolution of the pore fluid environment. From the association of methane gas hydrates, burial depth, and low-chloride interstitial fluids, we suggest an additional process that could contribute to the characteristic chloride depletion in pore fluids of active margins: release of interlayer water from clays without a mineral phase change. The shelf sediments also contain a subsurface brine that stretches for more than 500 km from north to south over the area drilled. The source of the brine remains uncertain, although the composition of the oxygen isotopes suggests dissolution of evaporites by seawater.

Spatio-Temporal Variation in Effects of Upwelling on the Fatty Acid Composition of Benthic Filter Feeders in the Southern Benguela Ecosystem: Not All Upwelling Is Equal.

Directory of Open Access Journals (Sweden)

Eleonora Puccinelli

Full Text Available Variability in mesoscale nearshore oceanographic conditions plays an important role in the distribution of primary production and food availability for intertidal consumers. Advection of nutrient rich waters by upwelling usually allows the proliferation of diatoms, later replaced by dinoflagellates. We examined upwelling effects on the fatty acid (FA signature of a benthic intertidal filter feeder to identify its response to pulsed variability in food availability. The study took place in two contrasting seasons and at two upwelling and two non-upwelling sites interspersed within the southern Benguela upwelling system of South Africa. We investigated the FA composition of the adductor muscles and gonads of the mussel Mytilus galloprovincialis to assess how FA are apportioned to the different tissues and whether this changes between upwelling and non-upwelling conditions. In situ temperature loggers used to identify upwelling conditions at the four sites indicated that such events occurred only at the upwelling centres and only in summer. Tissues differed strongly, with gonads presenting a higher proportion of essential FAs. This could reflect the faster turnover rate of gonad tissue or preferential retention of specific FA for reproductive purposes. FA composition did not vary as a direct function of upwelling, but there were strong dissimilarities among sites. Upwelling influenced mussel diets at one upwelling site while at the other, the expected signature of upwelling was displaced downstream of the core of upwelling. Condition Index (CI and Gonad Index (GI differed among sites and were not influenced by upwelling, with GI being comparable among sites. In addition, FA proportions were consistent among sites, indicating similar food quality and quantity over time and under upwelling and non-upwelling conditions. This suggests that the influence of upwelling on the west coast of South Africa is pervasive and diffuse, rather than discrete; while

Contrasting genomic properties of free-living and particle-attached microbial assemblages within a coastal ecosystem

Directory of Open Access Journals (Sweden)

Maria W Smith

2013-05-01

Full Text Available The Columbia River (CR is a powerful economic and environmental driver in the US Pacific Northwest. Microbial communities in the water column were analyzed from four diverse habitats: 1 an estuarine turbidity maximum (ETM; 2 a chlorophyll maximum of the river plume; 3 an upwelling-associated hypoxic zone; and 4 the deep ocean bottom. Three size fractions, 0.1-0.8, 0.8-3 and 3-200 μm were collected for each habitat in August 2007, and used for DNA isolation and 454 sequencing, resulting in 12 metagenomes of >5 million reads (>1.6 Gbp. To characterize the dominant microorganisms and metabolisms contributing to coastal biogeochemistry, we used predicted peptide and rRNA data. The 3- and 0.8-μm metagenomes, representing particulate fractions, were taxonomically diverse across habitats. The 3-μm size fractions contained a high abundance of eukaryota with diatoms dominating the hypoxic water and plume, while cryptophytes were more abundant in the ETM. The 0.1-μm metagenomes represented mainly free-living bacteria and archaea. The most abundant archaeal hits were observed in the deep ocean and hypoxic water (19% of prokaryotic peptides in the 0.1-μm metagenomes, and were homologous to Nitrosopumilus maritimus (ammonia-oxidizing Thaumarchaeota. Bacteria dominated metagenomes of all samples. In the euphotic zone (estuary, plume and hypoxic ocean, the most abundant bacterial taxa (≥40 % of prokaryotic peptides represented aerobic photoheterotrophs. In contrast, the low-oxygen, deep water metagenome was enriched with sequences for strict and facultative anaerobes. Interestingly, many of the same anaerobic bacterial families were enriched in the 3-μm size fraction of the ETM (2-10X more abundant relative to the 0.1-μm metagenome, indicating possible formation of anoxic microniches within particles. Results from this study provide a metagenome perspective on ecosystem-scale metabolism in an upwelling-influenced river-dominated coastal margin.

The physical structure of a cold filament in a Chilean upwelling zone (Península de Mejillones, Chile, 23°S)

Science.gov (United States)

Sobarzo, Marcus; Figueroa, Dante

2001-12-01

Cold filaments associated with Eastern Boundary Currents are typically narrower than 100 km but can be several hundred kilometers long, extending from the coast to the open ocean in upwelling areas. One such structure, observed off Península de Mejillones (23°S, Chile), was studied with both satellite images and two 5-days hydrographic cruises carried out during January 1997. The study used a coastal grid of 31 stations in an area of 165 ×155 km 2, approximately. The spatial distribution of the filament and its change between cruises are described from the horizontal distributions of dynamic height, temperature, salinity and dissolved oxygen. The filament was a shallow feature (thickness zone show the ascent of the shallow salinity minimum (SSM), and its extension toward the ocean, bound to the filament. It is concluded that Subantarctic Water ((SAAW) distinguish by low salinity, high dissolved oxygen) and Equatorial Subsurface Water ((ESSW) high salinity, low dissolved oxygen, high nutrient content) form this filament, and that their relative proportions depend on the strength of the coastal upwelling. Thus, the knowledge of the dynamics of these structures is fundamental to better understanding of the spatial distribution of important biological variables, such as nutrients and chlorophyll, in the coastal ecosystem.

Combined fishing and climate forcing in the southern Benguela upwelling ecosystem: an end-to-end modelling approach reveals dampened effects.

Directory of Open Access Journals (Sweden)

Morgane Travers-Trolet

Full Text Available The effects of climate and fishing on marine ecosystems have usually been studied separately, but their interactions make ecosystem dynamics difficult to understand and predict. Of particular interest to management, the potential synergism or antagonism between fishing pressure and climate forcing is analysed in this paper, using an end-to-end ecosystem model of the southern Benguela ecosystem, built from coupling hydrodynamic, biogeochemical and multispecies fish models (ROMS-N2P2Z2D2-OSMOSE. Scenarios of different intensities of upwelling-favourable wind stress combined with scenarios of fishing top-predator fish were tested. Analyses of isolated drivers show that the bottom-up effect of the climate forcing propagates up the food chain whereas the top-down effect of fishing cascades down to zooplankton in unfavourable environmental conditions but dampens before it reaches phytoplankton. When considering both climate and fishing drivers together, it appears that top-down control dominates the link between top-predator fish and forage fish, whereas interactions between the lower trophic levels are dominated by bottom-up control. The forage fish functional group appears to be a central component of this ecosystem, being the meeting point of two opposite trophic controls. The set of combined scenarios shows that fishing pressure and upwelling-favourable wind stress have mostly dampened effects on fish populations, compared to predictions from the separate effects of the stressors. Dampened effects result in biomass accumulation at the top predator fish level but a depletion of biomass at the forage fish level. This should draw our attention to the evolution of this functional group, which appears as both structurally important in the trophic functioning of the ecosystem, and very sensitive to climate and fishing pressures. In particular, diagnoses considering fishing pressure only might be more optimistic than those that consider combined effects

Zooplankton Responses to Low-Oxygen Condition upon a Shallow Oxygen Minimum Zone in the Upwelling Region off Chile

Science.gov (United States)

Hidalgo, P.; Escribano, R.

2015-12-01

A shallow oxygen minimum zone (OMZ) is a critical component in the coastal upwelling ecosystem off Chile. This OMZ causes oxygen-deficient water entering the photic layer and affecting plankton communities having low tolerance to hypoxia. Variable, and usually species-dependent, responses of zooplankton to hypoxia condition can be found. Most dominant species avoid hypoxia by restricting their vertical distribution, while others can temporarily enter and even spent part of their life cycle within the OMZ. Whatever the case, low-oxygen conditions appear to affect virtually all vital rates of zooplankton, such as mortality, fecundity, development and growth and metabolism, and early developmental stages seem more sensitive, with significant consequences for population and community dynamics. For most study cases, these effects are negative at individual and population levels. Observations and predictions upon increasing upwelling intensity over the last 20-30 years indicate a gradual shoaling of the OMZ, and so that an expected enhancement of these negative effects of hypoxia on the zooplankton community. Unknown processes of adaptation and community-structure adjustments are expected to take place with uncertain consequences for the food web of this highly productive eastern boundary current ecosystem.

Factors structuring the phytoplankton community in the upwelling site off El Loa River in northern Chile

Science.gov (United States)

Herrera, Liliana; Escribano, Ruben

2006-06-01

Understanding processes affecting the structure of the autotrophic community in marine ecosystems is relevant because species-dependent characters may affect productivity and carbon fluxes of the ocean. In this work, we studied the influence of oceanographic variability on phytoplankton species composition at a coastal upwelling site off northern Chile. Four seasonal cruises carried out during 2003 off El Loa River (21°S) showed that upwelling occurs year-round supporting a large number of diatoms, dinoflagellates, naked nanoflagellates, and silicoflagellates. The analysis of species composition showed that changes in the structure of the autotrophic community are expressed both in abundance and in differences in species assemblages. These changes occurred not only over the seasonal scale but also over the spatial pattern of distribution, and they correlated well to temporal variability of upwelling and spatial variation of upwelling conditions over the cross-shelf axis. A K-means clustering and principal component analyses showed that species assemblages can be represented by few dominant species strongly coupled to alternate upwelling vs. non-upwelling conditions. Both conditions are well defined, and mostly explained by changes in depth of the upper boundary of the oxygen minimum zone (OMZ) (a prominent feature in northern Chile), surface temperature and water column stratification. Abundance of dominant phytoplankton species were strongly correlated to both OMZ depth and water column stratification. Processes through which OMZ depth might influence species abundance and composition are unknown, although they may relate to changes in redox conditions which affect the nutrient field. Another explanation may relate to changes in grazing pressure derived from the effect of low oxygen water on zooplankton vertical distribution.

Icefield-to-ocean linkages across the northern Pacific coastal temperate rainforest ecosystem

Science.gov (United States)

O'Neel, Shad; Hood, Eran; Bidlack, Allison L.; Fleming, Sean W.; Arimitsu, Mayumi L.; Arendt, Anthony; Burgess, Evan W.; Sergeant, Christopher J.; Beaudreau, Anne E.; Timm, Kristin; Hayward, Gregory D.; Reynolds, Joel H.; Pyare, Sanjay

2015-01-01

Rates of glacier mass loss in the northern Pacific coastal temperate rainforest (PCTR) are among the highest on Earth, and changes in glacier volume and extent will affect the flow regime and chemistry of coastal rivers, as well as the nearshore marine ecosystem of the Gulf of Alaska. Here we synthesize physical, chemical and biological linkages that characterize the northern PCTR ecosystem, with particular emphasis on the potential impacts of glacier change in the coastal mountain ranges on the surface–water hydrology, biogeochemistry, coastal oceanography and aquatic ecology. We also evaluate the relative importance and interplay between interannual variability and long-term trends in key physical drivers and ecological responses. To advance our knowledge of the northern PCTR, we advocate for cross-disciplinary research bridging the icefield-to-ocean ecosystem that can be paired with long-term scientific records and designed to inform decisionmakers.

Upwelling regime off the Cabo Frio region in Brazil and impact on acoustic propagation.

Science.gov (United States)

Calado, Leandro; Camargo Rodríguez, Orlando; Codato, Gabriel; Contrera Xavier, Fabio

2018-03-01

This work introduces a description of the complex upwelling regime off the Cabo Frio region in Brazil and shows that ocean modeling, based on the feature-oriented regional modeling system (FORMS) technique, can produce reliable predictions of sound speed fields for the corresponding shallow water environment. This work also shows, through the development of simulations, that the upwelling regime can be responsible for the creation of shadow coastal zones, in which the detection probability is too low for an acoustic source to be detected. The development of the FORMS technique and its validation with real data, for the particular region of coastal upwelling off Cabo Frio, reveals the possibility of a sustainable and reliable forecast system for the corresponding (variable in space and time) underwater acoustic environment.

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.

Natural and human-induced hypoxia and consequences for coastal areas: synthesis and future development

Directory of Open Access Journals (Sweden)

J. Zhang

2010-05-01

Full Text Available Hypoxia has become a world-wide phenomenon in the global coastal ocean and causes a deterioration of the structure and function of ecosystems. Based on the collective contributions of members of SCOR Working Group #128, the present study provides an overview of the major aspects of coastal hypoxia in different biogeochemical provinces, including estuaries, coastal waters, upwelling areas, fjords and semi-enclosed basins, with various external forcings, ecosystem responses, feedbacks and potential impact on the sustainability of the fishery and economics. The obvious external forcings include freshwater runoff and other factors contributing to stratification, organic matter and nutrient loadings, as well as exchange between coastal and open ocean water masses. Their different interactions set up mechanisms that drive the system towards hypoxia. Coastal systems also vary in their relative susceptibility to hypoxia depending on their physical and geographic settings. It is understood that coastal hypoxia has a profound impact on the sustainability of ecosystems, which can be seen, for example, by the change in the food-web structure and system function; other influences include compression and loss of habitat, as well as changes in organism life cycles and reproduction. In most cases, the ecosystem responds to the low dissolved oxygen in non-linear ways with pronounced feedbacks to other compartments of the Earth System, including those that affect human society. Our knowledge and previous experiences illustrate that there is a need to develop new observational tools and models to support integrated research of biogeochemical dynamics and ecosystem behavior that will improve confidence in remediation management strategies for coastal hypoxia.

Natural and human-induced hypoxia and consequences for coastal areas: synthesis and future development

Science.gov (United States)

Zhang, J.; Gilbert, D.; Gooday, A. J.; Levin, L.; Naqvi, S. W. A.; Middelburg, J. J.; Scranton, M.; Ekau, W.; Peña, A.; Dewitte, B.; Oguz, T.; Monteiro, P. M. S.; Urban, E.; Rabalais, N. N.; Ittekkot, V.; Kemp, W. M.; Ulloa, O.; Elmgren, R.; Escobar-Briones, E.; van der Plas, A. K.

2010-05-01

Hypoxia has become a world-wide phenomenon in the global coastal ocean and causes a deterioration of the structure and function of ecosystems. Based on the collective contributions of members of SCOR Working Group #128, the present study provides an overview of the major aspects of coastal hypoxia in different biogeochemical provinces, including estuaries, coastal waters, upwelling areas, fjords and semi-enclosed basins, with various external forcings, ecosystem responses, feedbacks and potential impact on the sustainability of the fishery and economics. The obvious external forcings include freshwater runoff and other factors contributing to stratification, organic matter and nutrient loadings, as well as exchange between coastal and open ocean water masses. Their different interactions set up mechanisms that drive the system towards hypoxia. Coastal systems also vary in their relative susceptibility to hypoxia depending on their physical and geographic settings. It is understood that coastal hypoxia has a profound impact on the sustainability of ecosystems, which can be seen, for example, by the change in the food-web structure and system function; other influences include compression and loss of habitat, as well as changes in organism life cycles and reproduction. In most cases, the ecosystem responds to the low dissolved oxygen in non-linear ways with pronounced feedbacks to other compartments of the Earth System, including those that affect human society. Our knowledge and previous experiences illustrate that there is a need to develop new observational tools and models to support integrated research of biogeochemical dynamics and ecosystem behavior that will improve confidence in remediation management strategies for coastal hypoxia.

Does mesoscale matters in decadal changes observed in the northern Canary upwelling system?

Science.gov (United States)

Relvas, P.; Luís, J.; Santos, A. M. P.

2009-04-01

The Western Iberia constitutes the northern limb of the Canary Current Upwelling System, one of the four Eastern Boundary Upwelling Systems of the world ocean. The strong dynamic link between the atmosphere and the ocean makes these systems highly sensitive to global change, ideal to monitor and investigate its effects. In order to investigate decadal changes of the mesoscale patterns in the Northern Canary upwelling system (off Western Iberia), the field of the satellite-derived sea surface temperature (SST) trends was built at the pixel scale (4x4 km) for the period 1985-2007, based on the monthly mean data from the Advanced Very High Resolution Radiometer (AVHRR) on board NOAA series satellites, provided by the NASA Physical Oceanography Distributed Active Archive Center (PO.DAAC) at the Jet Propulsion Laboratory. The time series were limited to the nighttime passes to avoid the solar heating effect and a suite of procedures were followed to guarantee that the temperature trends were not biased towards the seasonally more abundant summer data, when the sky is considerably clear. A robust linear fit was applied to each individual pixel, crossing along the time the same pixel in all the processed monthly mean AVHRR SST images from 1985 until 2007. The field of the SST trends was created upon the slopes of the linear fits applied to each pixel. Monthly mean SST time series from the one degree enhanced International Comprehensive Ocean-Atmosphere Data Set (ICOADS) and from near-shore measurements collected on a daily basis by the Portuguese Meteorological Office (IM) are also used to compare the results and extend the analysis back until 1960. A generalized warming trend is detected in the coastal waters off Western Iberia during the last decades, no matter which data set we analyse. However, significant spatial differences in the warming rates are observed in the satellite-derived SST trends. Remarkably, off the southern part of the Western Iberia the known

Mussel farming impact on pelagic production and respiration rates in a coastal upwelling embayment (Ría de Vigo, NW Spain)

Science.gov (United States)

Froján, María; Castro, Carmen G.; Zúñiga, Diana; Arbones, Belén; Alonso-Pérez, Fernando; Figueiras, Francisco G.

2018-05-01

This paper provides the first diagnosis of the impact of mussel farming on the primary production (PP) and the metabolic balance in a coastal upwelling region (Ría de Vigo). Measurements of size-fractionated PP and microbial plankton metabolism were performed outside (reference station; ReS) and inside the farming area (raft station; RaS). At ReS, integrated PP was higher during upwelling (1.05 ± 0.45 g C m-2 d-1) with microphytoplankton dominating carbon fixation (74 ± 14%). The significance of nanophytoplankton and picophytoplankton increased during winter linked to lower PP (0.24 ± 0.03 g C m-2 d-1). Water column at ReS was always autotrophic with net community production (NCP) ranging from 186 ± 67 mmol O2 m-2 d-1 during upwelling to 43 ± 22 mmol O2 m-2 d-1 in winter. At RaS, there was a decrease in PP attributable not only to mussel consumption but also to the lower irradiance under mussel rafts. Concomitant decrease in NCP was also observed (by 56%), yet remained autotrophic, supporting the view that under current conditions food does not limit mussel growth in the Ría, thus securing the carrying capacity of the system in terms of production.

Estimating global "blue carbon" emissions from conversion and degradation of vegetated coastal ecosystems.

Directory of Open Access Journals (Sweden)

Linwood Pendleton

Full Text Available Recent attention has focused on the high rates of annual carbon sequestration in vegetated coastal ecosystems--marshes, mangroves, and seagrasses--that may be lost with habitat destruction ('conversion'. Relatively unappreciated, however, is that conversion of these coastal ecosystems also impacts very large pools of previously-sequestered carbon. Residing mostly in sediments, this 'blue carbon' can be released to the atmosphere when these ecosystems are converted or degraded. Here we provide the first global estimates of this impact and evaluate its economic implications. Combining the best available data on global area, land-use conversion rates, and near-surface carbon stocks in each of the three ecosystems, using an uncertainty-propagation approach, we estimate that 0.15-1.02 Pg (billion tons of carbon dioxide are being released annually, several times higher than previous estimates that account only for lost sequestration. These emissions are equivalent to 3-19% of those from deforestation globally, and result in economic damages of $US 6-42 billion annually. The largest sources of uncertainty in these estimates stems from limited certitude in global area and rates of land-use conversion, but research is also needed on the fates of ecosystem carbon upon conversion. Currently, carbon emissions from the conversion of vegetated coastal ecosystems are not included in emissions accounting or carbon market protocols, but this analysis suggests they may be disproportionally important to both. Although the relevant science supporting these initial estimates will need to be refined in coming years, it is clear that policies encouraging the sustainable management of coastal ecosystems could significantly reduce carbon emissions from the land-use sector, in addition to sustaining the well-recognized ecosystem services of coastal habitats.

Phytoplankton biomass and microbial abundances during the spring upwelling season in the coastal area off Concepción, central-southern Chile: Variability around a time series station

Science.gov (United States)

Morales, Carmen E.; Anabalón, Valeria

2012-01-01

In the coastal system off Concepción, time series observations at a fixed station (St. 18) have shown strong seasonal changes in the oceanographic environment of the upper layer (blooms, dominated by microplanktonic diatoms, have usually overshadowed the relevance of the smaller microbial components during upwelling. This study focuses on the variability of oceanographic conditions and their association with the structure of the planktonic community (size fractionated chlorophyll-a and microbial abundances) in the upper layer during the upwelling season, examining the extent to which St. 18 is representative of the coastal system off Concepción during springtime. For this purpose, data from three consecutive springs (2004, 2005, 2006) were compared, which included cruises for all years (8 stations around St. 18) as well as monthly sampling at St. 18. Most of the spatial (submesoscale) variability in chlorophyll-a and the microbial components was not significant, but data dispersion around mean values was high. Water column structure (temperature and salinity) in the upper layer explained a significant fraction (25-65%) of the spatial variability in most of the planktonic components; their responses to oceanographic variability were linear in some cases and non-linear in others. For the most part, St. 18 appears to adequately represent mean oceanographic conditions and the structure of planktonic communities in the coastal waters off Concepción during springtime, however spatial variability needs to be taken into account in the interpretations of temporal changes at this fixed station as well as in assessments of carbon flow within, and exportation processes from, this upwelling system.

Joint effect of freshwater plume and coastal upwelling on phytoplankton growth off the Changjiang River

Science.gov (United States)

Tseng, Y.-F.; Lin, J.; Dai, M.; Kao, S.-J.

2014-01-01

The Changjiang (Yangtze) River discharges vast amount of unbalanced nutrients (dissolved inorganic nitrogen and phosphorus with N / P ratio > 80 in general) into the East China Sea in summer. To study nutrient dynamics and P-stress potential for phytoplankton, a cruise was conducted in the Changjiang plume during summer 2011. With 3-D observations of nutrients, chlorophyll a (Chl a), and bulk alkaline phosphatase activity (APA), we concluded that the Changjiang Diluted Water and coastal upwelling significantly influenced the horizontal and vertical heterogeneities of phytoplankton P deficiency in the Changjiang plume. Allochthonous APA was detected at nutrient-enriched freshwater end. Excessive N (~ 10 to 112 μM) was observed throughout the entire plume surface. In the plume fringe featuring stratification and excess N, diapycnal phosphate supply was blocked and phytoplankton APA was stimulated for growth. We observed an upwelling just attaching to the turbidity front at seaward side where Chl a peaked yet much less APA was detected. An external phosphate supply from subsurface, which promoted phytoplankton growth but inhibited APA, was suggested to be sourced from the Nearshore Kuroshio Branch Current. In the so hydrographically complicated Changjiang plume, phosphate supply instead of its concentration may be more important in determining the expression of APA. Meanwhile, allochthonous APA may also alter the usefulness of APA as a P-stress indicator.

Response of Mytilus edulis to enhanced phytoplankton availibility by controlled upwelling in an oligographic fjord

NARCIS (Netherlands)

Strohmeier, T.; Strand, Ø.; Alunno-Bruscia, M.; Duinker, A.; Rosland, R.; Jansen, H.M.

2015-01-01

The controlled upwelling of nutrient-rich deep water in oligotrophic coastal regions has been proposed as a means of increasing phytoplankton and, subsequently, bivalve aquaculture production. This was tested as part of a large-scale upwelling experiment in an oligotrophic environment (Lysefjord,

Upwelling filaments are cold, typically narrow features in surface ...

African Journals Online (AJOL)

spamer

They are defined by strong ... transporting coastally upwelled water to the deep ... surface temperature anomaly up to 2°C. The cool temperature signal was restricted to a shallow surface ... towards the important process of exchanges between.

Major threats of pollution and climate change to global coastal ecosystems and enhanced management for sustainability.

Science.gov (United States)

Lu, Yonglong; Yuan, Jingjing; Lu, Xiaotian; Su, Chao; Zhang, Yueqing; Wang, Chenchen; Cao, Xianghui; Li, Qifeng; Su, Jilan; Ittekkot, Venugopalan; Garbutt, Richard Angus; Bush, Simon; Fletcher, Stephen; Wagey, Tonny; Kachur, Anatolii; Sweijd, Neville

2018-08-01

Coastal zone is of great importance in the provision of various valuable ecosystem services. However, it is also sensitive and vulnerable to environmental changes due to high human populations and interactions between the land and ocean. Major threats of pollution from over enrichment of nutrients, increasing metals and persistent organic pollutants (POPs), and climate change have led to severe ecological degradation in the coastal zone, while few studies have focused on the combined impacts of pollution and climate change on the coastal ecosystems at the global level. A global overview of nutrients, metals, POPs, and major environmental changes due to climate change and their impacts on coastal ecosystems was carried out in this study. Coasts of the Eastern Atlantic and Western Pacific were hotspots of concentrations of several pollutants, and mostly affected by warming climate. These hotspots shared the same features of large populations, heavy industry and (semi-) closed sea. Estimation of coastal ocean capital, integrated management of land-ocean interaction in the coastal zone, enhancement of integrated global observation system, and coastal ecosystem-based management can play effective roles in promoting sustainable management of coastal marine ecosystems. Enhanced management from the perspective of mitigating pollution and climate change was proposed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Near-surface temperature gradient in a coastal upwelling regime

Science.gov (United States)

Maske, H.; Ochoa, J.; Almeda-Jauregui, C. O.; Ruiz-de la Torre, M. C.; Cruz-López, R.; Villegas-Mendoza, J. R.

2014-08-01

In oceanography, a near homogeneous mixed layer extending from the surface to a seasonal thermocline is a common conceptual basis in physics, chemistry, and biology. In a coastal upwelling region 3 km off the coast in the Mexican Pacific, we measured vertical density gradients with a free-rising CTD and temperature gradients with thermographs at 1, 3, and 5 m depths logging every 5 min during more than a year. No significant salinity gradient was observed down to 10 m depth, and the CTD temperature and density gradients showed no pronounced discontinuity that would suggest a near-surface mixed layer. Thermographs generally logged decreasing temperature with depth with gradients higher than 0.2 K m-1 more than half of the time in the summer between 1 and 3 m, 3 and 5 m and in the winter between 1 and 3 m. Some negative temperature gradients were present and gradients were generally highly variable in time with high peaks lasting fractions of hours to hours. These temporal changes were too rapid to be explained by local heating or cooling. The pattern of positive and negative peaks might be explained by vertical stacks of water layers of different temperatures and different horizontal drift vectors. The observed near-surface gradient has implications for turbulent wind energy transfer, vertical exchange of dissolved and particulate water constituents, the interpretation of remotely sensed SST, and horizontal wind-induced transport.

Comparative study of potential transfer of natural and anthropogenic cadmium to plankton communities in the North-West African upwelling

Energy Technology Data Exchange (ETDEWEB)

Auger, P.A., E-mail: pierreamael.auger@gmail.com [Laboratoire de Physique des Océans (LPO), UMR-CNRS 6523/IFREMER/IRD/UBO, BP70, 29280 Plouzané (France); Machu, E.; Gorgues, T.; Grima, N. [Laboratoire de Physique des Océans (LPO), UMR-CNRS 6523/IFREMER/IRD/UBO, BP70, 29280 Plouzané (France); Waeles, M. [Université de Bretagne Occidentale (UBO), Laboratoire de l' Environnement Marin (LEMAR), UMR-CNRS 6539/IRD/UBO, place N. Copernic, 29280 Plouzané (France)

2015-02-01

A Lagrangian approach based on a physical–biogeochemical modeling was used to compare the potential transfer of cadmium (Cd) from natural and anthropogenic sources to plankton communities (Cd-uptake) in the North-West African upwelling. In this region, coastal upwelling was estimated to be the main natural source of Cd while the most significant anthropogenic source for marine ecosystem is provided by phosphate industry. In our model experiment, Cd-uptake (natural or anthropogenic) in the North-West African upwelling is the result of an interplay between the Cd dispersion (by advection processes) and the simulated biological productivity. In the Moroccan waters, advection processes limit the residence time of water masses resulting in a low natural Cd-uptake by plankton communities while anthropogenic Cd-uptake is high. As expected, the situation is reversed in the Senegalo-Mauritanian upwelling where natural Cd-uptake is higher than anthropogenic Cd-uptake. Based upon an estimate of Cd sources, our modeling study shows, unexpectedly, that the anthropogenic signal of potential Cd-bioaccumulation in the Moroccan upwelling is of the same order of magnitude as the natural signal mainly present in the Senegalo-Mauritanian upwelling region. A comparison with observed Cd levels in mollusk and fishes, which shows overall agreement with our simulations, is confirming our estimates. - Highlights: • We model the physical–biogeochemical dynamics in the North-West African upwelling. • We model the transport of cadmium from natural and anthropogenic sources. • We derive proxies of potential cadmium absorption and bioaccumulation in the plankton food chain. • The anthropogenic signal off Morocco at least equals the natural upwelling signal off Mauritania. • We compare our results with observed cadmium levels in mollusks and fishes.

Comparative study of potential transfer of natural and anthropogenic cadmium to plankton communities in the North-West African upwelling

International Nuclear Information System (INIS)

Auger, P.A.; Machu, E.; Gorgues, T.; Grima, N.; Waeles, M.

2015-01-01

A Lagrangian approach based on a physical–biogeochemical modeling was used to compare the potential transfer of cadmium (Cd) from natural and anthropogenic sources to plankton communities (Cd-uptake) in the North-West African upwelling. In this region, coastal upwelling was estimated to be the main natural source of Cd while the most significant anthropogenic source for marine ecosystem is provided by phosphate industry. In our model experiment, Cd-uptake (natural or anthropogenic) in the North-West African upwelling is the result of an interplay between the Cd dispersion (by advection processes) and the simulated biological productivity. In the Moroccan waters, advection processes limit the residence time of water masses resulting in a low natural Cd-uptake by plankton communities while anthropogenic Cd-uptake is high. As expected, the situation is reversed in the Senegalo-Mauritanian upwelling where natural Cd-uptake is higher than anthropogenic Cd-uptake. Based upon an estimate of Cd sources, our modeling study shows, unexpectedly, that the anthropogenic signal of potential Cd-bioaccumulation in the Moroccan upwelling is of the same order of magnitude as the natural signal mainly present in the Senegalo-Mauritanian upwelling region. A comparison with observed Cd levels in mollusk and fishes, which shows overall agreement with our simulations, is confirming our estimates. - Highlights: • We model the physical–biogeochemical dynamics in the North-West African upwelling. • We model the transport of cadmium from natural and anthropogenic sources. • We derive proxies of potential cadmium absorption and bioaccumulation in the plankton food chain. • The anthropogenic signal off Morocco at least equals the natural upwelling signal off Mauritania. • We compare our results with observed cadmium levels in mollusks and fishes

Upwelling and Other Environmental Influences on Growth of a Nearshore Benthic Fish

Science.gov (United States)

von Biela, V. R.; Zimmerman, C. E.; Kruse, G. H.; Mueter, F. J.; Black, B.; Douglas, D. C.; Bodkin, J. L.

2016-02-01

The role of upwelling in nearshore benthic systems is more uncertain compared to the relatively strong positive associations with pelagic production. To understand how upwelling and other environmental conditions influence nearshore benthic production, we developed an annual index of production from growth increments recorded in otoliths of kelp greenling (Hexagrammos decagrammus) at nine sites in the seasonally-upwelling California Current and downwelling Alaska Coastal currents. Kelp greenling are a benthic-feeding fish common in kelp forests with food webs sustained by both kelp and phytoplankton primary production. We explored the influence of basin- and local-scale conditions, including upwelling, across all seasons at lags up to two years taken to represent changes in the quantity and quality of prey. Upwelling strength was positively related to fish growth in both current systems, although relationships in the Alaska Coastal Current were indicative of faster growth with relaxed downwelling, rather than upwelling. Looking across a suite of basin- and local-scale environmental indicators, complex relationships emerged in the California Current, with faster growth related to within-year warm conditions and lagged-year cool conditions. In contrast, fish in the downwelling system grew faster both during and subsequent to warm conditions. The complex lag-dependent dynamics in the upwelling system may reflect differences in conditions that promote quantity versus quality of benthic invertebrate prey. Thus, we hypothesize that benthic production is maximized when cool and warm years alternate during periods of high frequency climate variability in the California Current. Such a pattern is consistent with previous findings suggesting that benthic invertebrate abundance (e.g., recruitment) is food-limited during warm years with reduced upwelling, while quality (e.g., energy content) is temperature-limited during cool years.

Quantifying the impact of an upwelling filament on the physical-chemical-biological interactions off SW Iberia

Science.gov (United States)

Cravo, A.; Sanchez, R.; Monteiro, C.; Cardeira, S.; Madureira, M.; Rita, F.; Relvas, P.

2017-12-01

Upwelling filaments are mesoscale structures of cold water that stretch seaward in a tongue-like shape with origin in the coastal upwelling zone. Filaments off the Iberian Peninsula are recurrent, showing similarities with those in the Californian coast. The Cape São Vicente, the SW tip of the Iberian Peninsula, is the root of recurrent filaments observed in the satellite imagery during the upwelling season. However, the understanding of its physical and chemical impact on the biological productivity is rather limited. There, a relatively small filament ( 80 km long) was investigated through remote sensing and in situ multidisciplinary observations during an upwelling favourable wind relaxation event, but just after an intense upwelling period. A total of 42 CTD+Rosette casts up to 400 m depth were distributed on an almost regular grid of 15 km mean spacing guided by guided by satellite SST imagery transmitted to the ship in near-real time. The parameters sampled during the sea campaign included: velocity field sampled along the ship track through a hull-mounted 38 kHz RDI ADCP, meteorological variables, temperature, salinity, chlorophyll a, dissolved oxygen, nitrate, phosphate, silicate, cadmium, lead and zinc. The extent of the impact of the filament was evaluated by quantifying the cross-shelf transports of several properties. The amounts conveyed by the filament were much stronger than those expected by the wind-driven Ekman mechanism, showing that it represents an efficient feature for the exchange of water, dissolved and particulate matter from the productive shelf towards the oligotrophic offshore region. Considering the periods of strong upwelling events and the extent of their duration along the year, the amounts of exported matter will certainly enhance the biological productivity of these waters, including its fisheries. These filament data contribute to better understand the physical-chemical-biological interactions of this regional ecosystem.

Response of the Benguela upwelling systems to spatial variations in the wind stress

Science.gov (United States)

Fennel, Wolfgang; Junker, Tim; Schmidt, Martin; Mohrholz, Volker

2012-08-01

In this paper we combine field observations, numerical modeling and an idealized analytical theory to study some features of the Benguela upwelling system. The current system can be established through a combination of observations and realistic simulations with an advanced numerical model. The poleward undercurrent below the equator-ward coastal jet is often found as a countercurrent that reaches the sea surface seaward of the coastal jet. The coastal band of cold upwelled water appears to broaden from south to north and at the northern edge of the wind band an offshore flow is often detected, which deflects the coastal Angola current to the west. These features can be explained and understood with an idealized analytical model forced by a spatially variable wind. A crucial role is played by the wind stress curl, which shapes the oceanic response through Ekman-pumping. The interplay of the curl driven effects and the coastal Ekman upwelling together with the coastal jet, Kelvin waves, and the undercurrent is the key to understand the formation of the three-dimensional circulation patterns in the Benguela system. While the numerical model is based on the full set of primitive equations, realistic topography and forcing, the analytic model uses a linear, flat-bottomed f-plane ocean, where the coast is a straight wall and the forcing is represented by an alongshore band of dome-shaped wind stress. Although the analytical model is highly idealized it is very useful to grasp the basic mechanisms leading to the response patterns.

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.

Natural and human-induced hypoxia and consequences for coastal areas: synthesis and future development

Science.gov (United States)

Zhang, J.; Gilbert, D.; Gooday, A.; Levin, L.; Naqvi, W.; Middelburg, J.; Scranton, M.; Ekau, W.; Pena, A.; Dewitte, B.; Oguz, T.; Monteiro, P. M. S.; Urban, E.; Rabalais, N.; Ittekkot, V.; Kemp, W. M.; Ulloa, O.; Elmgren, R.; Escobar-Briones, E.; van der Plas, A.

2009-11-01

Hypoxia has become a world-wide phenomenon in the global coastal ocean and causes deterioration of structure and function of ecosystems. Based on the collective contributions of members of SCOR Working Group #128, the present study provides an overview of the major aspects of coastal hypoxia in different biogeochemical provinces, including estuaries, upwelling areas, fjords and semi-enclosed basins, with various external forcings, ecosystem responses, feedbacks and potential impact on the sustainability of the fishery and economics. The obvious external forcings include fresh water runoff and other factors contributing to stratification, organic matter and nutrient loadings, as well as exchange between coastal and open ocean water masses; their different interactions set up mechanisms that drive the system towards hypoxia. However, whether the coastal environment becomes hypoxic or not, under the combination of external forcings, depends also on the nature of the ecosystem, e.g. physical and geographic settings. It is understood that coastal hypoxia has a profound impact on the sustainability of ecosystems, which can be seen, for example, by the change in the food-web structure and system function; other influences can be compression and loss of habitat, as well as change in life cycle and reproduction. In most cases, the ecosystem responds to the low dissolved oxygen in a non-linear way and has pronounced feedbacks to other compartments of the Earth System, hence affecting human society. Our knowledge and previous experiences illustrate that there is a need to develop new observational tools and models to support integrated research of biogeochemical dynamics and ecosystem behaviour that will improve confidence in remediation management strategies for coastal hypoxia.

GEO-CAPE Coastal Ecosystem Dynamics Imager (COEDI) Instrument Design

Data.gov (United States)

National Aeronautics and Space Administration — The primary goal of this study is to build a breadboard instrument and prove the functionality of the optical-mechanical assembly for the Coastal Ecosystem Dynamics...

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

Science.gov (United States)

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

2015-12-01

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

Differences in coastal and oceanic SST trends north of Yucatan Peninsula

Science.gov (United States)

Varela, R.; Costoya, X.; Enriquez, C.; Santos, F.; Gómez-Gesteira, M.

2018-06-01

The coastal area north of Yucatan has experienced a cooling SST trend from 1982 to 2015 during the upwelling season (May-September) that contrasts with the warming observed at the adjacent ocean area. Different drivers were analyzed to identify the possible causes of that unusual coastal cooling. Changes in coastal upwelling and in sea-atmosphere heat fluxes are not consistent with the observed coastal cooling. The eastward shift of the Yucatan Current observed over the last decades is hypothesized as the most probable cause of coastal cooling. This shift enhances the vertical transport of cold deeper water to the continental shelf from where it is pumped to the surface by upwelling favorable westerly winds.

Emerging methods for the study of coastal ecosystem landscape structure and change

Science.gov (United States)

Brock, John C.; Danielson, Jeffrey J.; Purkis, Sam

2013-01-01

Coastal landscapes are heterogeneous, dynamic, and evolve over a range of time scales due to intertwined climatic, geologic, hydrologic, biologic, and meteorological processes, and are also heavily impacted by human development, commercial activities, and resource extraction. A diversity of complex coastal systems around the globe, spanning glaciated shorelines to tropical atolls, wetlands, and barrier islands are responding to multiple human and natural drivers. Interdisciplinary research based on remote-sensing observations linked to process studies and models is required to understand coastal ecosystem landscape structure and change. Moreover, new techniques for coastal mapping and monitoring are increasingly serving the needs of policy-makers and resource managers across local, regional, and national scales. Emerging remote-sensing methods associated with a diversity of instruments and platforms are a key enabling element of integrated coastal ecosystem studies. These investigations require both targeted and synoptic mapping, and involve the monitoring of formative processes such as hydrodynamics, sediment transport, erosion, accretion, flooding, habitat modification, land-cover change, and biogeochemical fluxes.

Diversity and phosphate solubilization by bacteria isolated from Laki Island coastal ecosystem

Directory of Open Access Journals (Sweden)

SRI WIDAWATI

2011-01-01

Full Text Available Widawati S (2011 Diversity and phosphate solubilization by bacteria isolated from Laki Island coastal ecosystem. Biodiversitas 12: 17-21. Soil, water, sand, and plant rhizosphere samples collected from coastal ecosystem of Laki Island-Jakarta were screened for phosphate solubilizing bacteria (PSB. While the population was dependent on the cultivation media and the sample type, the highest bacterial population was observed in the rhizosphere of Ipomea aquatica. The PSB strains isolated from the sample registered 18.59 g-1L-1, 18.31 g-1L-1, and 5.68 g-1L-1 of calcium phosphate (Ca-P, Al-P and rock phosphate solubilization after 7-days. Phosphate solubilizing capacity was the highest in the Ca-P medium. Two strains, 13 and 14, registered highest Phosphomonoesterase activities (2.01 µgNP.g-1.h-1 and 1.85NP µg.g-1.h-1 were identified as Serattia marcescens, and Pseudomonas fluorescense, respectively. Both strains were isolated from the crops of Amaranthus hybridus and I. aquatica, respectively, which are commonly observed in coastal ecosystems. The presence of phosphate solubilizing microorganisms and their ability to solubilize various types of phosphate species are indicative of the important role of both species of bacteria in the biogeochemical cycle of phosphorus and the plant growth in coastal ecosystems.

Historical overfishing and the recent collapse of coastal ecosystems.

Science.gov (United States)

Jackson, J B; Kirby, M X; Berger, W H; Bjorndal, K A; Botsford, L W; Bourque, B J; Bradbury, R H; Cooke, R; Erlandson, J; Estes, J A; Hughes, T P; Kidwell, S; Lange, C B; Lenihan, H S; Pandolfi, J M; Peterson, C H; Steneck, R S; Tegner, M J; Warner, R R

2001-07-27

Ecological extinction caused by overfishing precedes all other pervasive human disturbance to coastal ecosystems, including pollution, degradation of water quality, and anthropogenic climate change. Historical abundances of large consumer species were fantastically large in comparison with recent observations. Paleoecological, archaeological, and historical data show that time lags of decades to centuries occurred between the onset of overfishing and consequent changes in ecological communities, because unfished species of similar trophic level assumed the ecological roles of overfished species until they too were overfished or died of epidemic diseases related to overcrowding. Retrospective data not only help to clarify underlying causes and rates of ecological change, but they also demonstrate achievable goals for restoration and management of coastal ecosystems that could not even be contemplated based on the limited perspective of recent observations alone.

Marine and coastal ecosystem services on the science-policy-practice nexus

NARCIS (Netherlands)

Drakou, Evangelia G.; Kermagoret, Charlène; Liquete, Camino; Ruiz-Frau, Ana; Burkhard, Kremena; Lillebø, Ana I.; Oudenhoven, van Alexander P.E.; Ballé-Béganton, Johanna; Rodrigues, João Garcia; Nieminen, Emmi; Oinonen, Soile; Ziemba, Alex; Gissi, Elena; Depellegrin, Daniel; Veidemane, Kristina; Ruskule, Anda; Delangue, Justine; Böhnke-Henrichs, Anne; Boon, Arjen; Wenning, Richard; Martino, Simone; Hasler, Berit; Termansen, Mette; Rockel, Mark; Hummel, Herman; Serafy, El Ghada; Peev, Plamen

2017-01-01

We compared and contrasted 11 European case studies to identify challenges and opportunities toward the operationalization of marine and coastal ecosystem service (MCES) assessments in Europe. This work is the output of a panel convened by the Marine Working Group of the Ecosystem Services

The roles of large top predators in coastal ecosystems: new insights from long term ecological research

Science.gov (United States)

Rosenblatt, Adam E.; Heithaus, Michael R.; Mather, Martha E.; Matich, Philip; Nifong, James C.; Ripple, William J.; Silliman, Brian R.

2013-01-01

During recent human history, human activities such as overhunting and habitat destruction have severely impacted many large top predator populations around the world. Studies from a variety of ecosystems show that loss or diminishment of top predator populations can have serious consequences for population and community dynamics and ecosystem stability. However, there are relatively few studies of the roles of large top predators in coastal ecosystems, so that we do not yet completely understand what could happen to coastal areas if large top predators are extirpated or significantly reduced in number. This lack of knowledge is surprising given that coastal areas around the globe are highly valued and densely populated by humans, and thus coastal large top predator populations frequently come into conflict with coastal human populations. This paper reviews what is known about the ecological roles of large top predators in coastal systems and presents a synthesis of recent work from three coastal eastern US Long Term Ecological Research (LTER) sites where long-term studies reveal what appear to be common themes relating to the roles of large top predators in coastal systems. We discuss three specific themes: (1) large top predators acting as mobile links between disparate habitats, (2) large top predators potentially affecting nutrient and biogeochemical dynamics through localized behaviors, and (3) individual specialization of large top predator behaviors. We also discuss how research within the LTER network has led to enhanced understanding of the ecological roles of coastal large top predators. Highlighting this work is intended to encourage further investigation of the roles of large top predators across diverse coastal aquatic habitats and to better inform researchers and ecosystem managers about the importance of large top predators for coastal ecosystem health and stability.

El Niño and similar perturbation effects on the benthos of the Humboldt, California, and Benguela Current upwelling ecosystems

Directory of Open Access Journals (Sweden)

W. E. Arntz

2006-01-01

zones, bringing a variety of (subtropical immigrants. The autochthonous benthic fauna emigrates to deeper water or poleward, or suffers mortality. However, some local macrofaunal species experience important population proliferations, presumably due to improved oxygenation (in the southern hemisphere, higher temperature tolerance, reduced competition or the capability to use different food. Both these negative and positive effects of El Niño influence local artisanal fisheries and the livelihood of coastal populations. In the Humboldt Current system the hypoxic seafloor at outer shelf depths receives important flushing from the equatorial zone, causing havoc on the sulphur bacteria mats and immediate recolonisation of the sediments by mega- and macrofauna. Conversely, off California, the intruding equatorial water masses appear to have lower oxygen than ambient waters, and may cause oxygen deficiency at upper slope depths. Effects of this change have not been studied in detail, although shrimp and other taxa appear to alter their distribution on the continental margin. Other properties and reactions of the two Pacific EBC benthic ecosystems to El Niño seem to differ, too, as does the overall impact of major episodes (e.g., 1982/1983(1984 vs. 1997/1998. The relation of the "Benguela Niño" to ENSO seems unclear although many Pacific-Atlantic ocean and atmosphere teleconnections have been described. Warm, low-oxygen equatorial water seems to be transported into the upwelling area by similar mechanisms as in the Pacific, but most major impacts on the eukaryotic biota obviously come from other, independent perturbations such as an extreme eutrophication of the sediments ensuing in sulphidic eruptions and toxic algal blooms. Similarities and differences of the Humboldt and California Current benthic ecosystems are discussed with particular reference to ENSO impacts since 1972/73. Where there are data available, the authors include the Benguela Current ecosystem as another

A meta-analysis of soil salinization effects on nitrogen pools, cycles and fluxes in coastal ecosystems.

Science.gov (United States)

Zhou, Minghua; Butterbach-Bahl, Klaus; Vereecken, Harry; Brüggemann, Nicolas

2017-03-01

Salinity intrusion caused by land subsidence resulting from increasing groundwater abstraction, decreasing river sediment loads and increasing sea level because of climate change has caused widespread soil salinization in coastal ecosystems. Soil salinization may greatly alter nitrogen (N) cycling in coastal ecosystems. However, a comprehensive understanding of the effects of soil salinization on ecosystem N pools, cycling processes and fluxes is not available for coastal ecosystems. Therefore, we compiled data from 551 observations from 21 peer-reviewed papers and conducted a meta-analysis of experimental soil salinization effects on 19 variables related to N pools, cycling processes and fluxes in coastal ecosystems. Our results showed that the effects of soil salinization varied across different ecosystem types and salinity levels. Soil salinization increased plant N content (18%), soil NH 4 + (12%) and soil total N (210%), although it decreased soil NO 3 - (2%) and soil microbial biomass N (74%). Increasing soil salinity stimulated soil N 2 O fluxes as well as hydrological NH 4 + and NO 2 - fluxes more than threefold, although it decreased the hydrological dissolved organic nitrogen (DON) flux (59%). Soil salinization also increased the net N mineralization by 70%, although salinization effects were not observed on the net nitrification, denitrification and dissimilatory nitrate reduction to ammonium in this meta-analysis. Overall, this meta-analysis improves our understanding of the responses of ecosystem N cycling to soil salinization, identifies knowledge gaps and highlights the urgent need for studies on the effects of soil salinization on coastal agro-ecosystem and microbial N immobilization. Additional increases in knowledge are critical for designing sustainable adaptation measures to the predicted intrusion of salinity intrusion so that the productivity of coastal agro-ecosystems can be maintained or improved and the N losses and pollution of the natural

Estimating Global “Blue Carbon” Emissions from Conversion and Degradation of Vegetated Coastal Ecosystems

Science.gov (United States)

Murray, Brian C.; Crooks, Stephen; Jenkins, W. Aaron; Sifleet, Samantha; Craft, Christopher; Fourqurean, James W.; Kauffman, J. Boone; Marbà, Núria; Megonigal, Patrick; Pidgeon, Emily; Herr, Dorothee; Gordon, David; Baldera, Alexis

2012-01-01

Recent attention has focused on the high rates of annual carbon sequestration in vegetated coastal ecosystems—marshes, mangroves, and seagrasses—that may be lost with habitat destruction (‘conversion’). Relatively unappreciated, however, is that conversion of these coastal ecosystems also impacts very large pools of previously-sequestered carbon. Residing mostly in sediments, this ‘blue carbon’ can be released to the atmosphere when these ecosystems are converted or degraded. Here we provide the first global estimates of this impact and evaluate its economic implications. Combining the best available data on global area, land-use conversion rates, and near-surface carbon stocks in each of the three ecosystems, using an uncertainty-propagation approach, we estimate that 0.15–1.02 Pg (billion tons) of carbon dioxide are being released annually, several times higher than previous estimates that account only for lost sequestration. These emissions are equivalent to 3–19% of those from deforestation globally, and result in economic damages of $US 6–42 billion annually. The largest sources of uncertainty in these estimates stems from limited certitude in global area and rates of land-use conversion, but research is also needed on the fates of ecosystem carbon upon conversion. Currently, carbon emissions from the conversion of vegetated coastal ecosystems are not included in emissions accounting or carbon market protocols, but this analysis suggests they may be disproportionally important to both. Although the relevant science supporting these initial estimates will need to be refined in coming years, it is clear that policies encouraging the sustainable management of coastal ecosystems could significantly reduce carbon emissions from the land-use sector, in addition to sustaining the well-recognized ecosystem services of coastal habitats. PMID:22962585

Understanding human impacts to tropical coastal ecosystems through integrated hillslope erosion measurements, optical coastal waters characterization, watershed modeling, marine ecosystem assessments, and natural resource valuations in two constrasting watersheds in Puerto Rico.

Science.gov (United States)

Ortiz-Zayas, J.; Melendez, J.; Barreto, M.; Santiago, L.; Torres-Perez, J. L.; Ramos-Scharron, C. E.; Figueroa, Y.; Setegn, S. G.; Guild, L. S.; Armstrong, R.

2017-12-01

Coastal ecosystems are an asset to many tropical island economies. In Puerto Rico, however, many invaluable coastal ecosystems are at risk due to multiple social and natural environmental stressors. To quantify the role of anthropogenic versus natural stressors, an integrated multidisciplinary approach was applied in two contrasting watersheds in Puerto Rico. The Rio Loco (RL) watershed in Southeastern Puerto Rico is hydrologically modified with interbasin water transfers, hydroelectric generation, and with water extraction for irrigation and water supply. Intensive agricultural production dominates both the lower and upper portions of the basin. In contrast, the Rio Grande de Manatí (RGM) shows a natural flow regime with minor flow regulation and limited agriculture. The Surface Water Assessment Tool (SWAT) was applied to each watershed to assess the effects of land use changes on water and sediment fluxes to coastal areas. From 1977 to 2016, forest areas increased in both watersheds due to the abandonment of farms in the mountains. However, in upper and lower RL, agricultural lands have remained active. Coffee plantations in the upper watershed contribute with high sediment loads, particularly in unpaved service roads. We hypothesize that water fluxes will be higher in the larger RGM than in RL. However, suspended sediment fluxes will be higher in the agriculturally active RL basin. A willingness-to-pay approach was applied to assess how residents from each watershed value water and coastal ecosystems revealing a general higher natural resources valuation in the RGM than in RL. Coastal ecosystems at each site revealed structural differences in benthic coral communities due to local currents influenced largely by coastal morphology. The optical properties of coastal waters are also being determined and linked to fluvial sediment fluxes. Stakeholder meetings are being held in each watershed to promote transfer of scientific insights into a sustainable coastal and

Ecosystem-based coastal defence in the face of global change.

Science.gov (United States)

Temmerman, Stijn; Meire, Patrick; Bouma, Tjeerd J; Herman, Peter M J; Ysebaert, Tom; De Vriend, Huib J

2013-12-05

The risk of flood disasters is increasing for many coastal societies owing to global and regional changes in climate conditions, sea-level rise, land subsidence and sediment supply. At the same time, in many locations, conventional coastal engineering solutions such as sea walls are increasingly challenged by these changes and their maintenance may become unsustainable. We argue that flood protection by ecosystem creation and restoration can provide a more sustainable, cost-effective and ecologically sound alternative to conventional coastal engineering and that, in suitable locations, it should be implemented globally and on a large scale.

Coastal Ocean Ecosystem Dynamics Imager Pointing Line-of-Sight Solution Development and Testing

Data.gov (United States)

National Aeronautics and Space Administration — A stable pointing line of sight solution is developed and tested in support of the Coastal Ocean Ecosystem Dynamics Imager for the GEOstationary Coastal and Air...

Some remarks on the functions of European coastal ecosystems

NARCIS (Netherlands)

van der Maarel, E

2003-01-01

Amongst the various functions of European coastal ecosystems the information functions are by far the most important. Information is provided mainly through the various aspects of biodiversity: taxon diversity, genetic diversity, community (P) diversity, phylogentic distinctiveness, rarity and

Embedding ecosystem services in coastal planning leads to better outcomes for people and nature.

Science.gov (United States)

Arkema, Katie K; Verutes, Gregory M; Wood, Spencer A; Clarke-Samuels, Chantalle; Rosado, Samir; Canto, Maritza; Rosenthal, Amy; Ruckelshaus, Mary; Guannel, Gregory; Toft, Jodie; Faries, Joe; Silver, Jessica M; Griffin, Robert; Guerry, Anne D

2015-06-16

Recent calls for ocean planning envision informed management of social and ecological systems to sustain delivery of ecosystem services to people. However, until now, no coastal and marine planning process has applied an ecosystem-services framework to understand how human activities affect the flow of benefits, to create scenarios, and to design a management plan. We developed models that quantify services provided by corals, mangroves, and seagrasses. We used these models within an extensive engagement process to design a national spatial plan for Belize's coastal zone. Through iteration of modeling and stakeholder engagement, we developed a preferred plan, currently under formal consideration by the Belizean government. Our results suggest that the preferred plan will lead to greater returns from coastal protection and tourism than outcomes from scenarios oriented toward achieving either conservation or development goals. The plan will also reduce impacts to coastal habitat and increase revenues from lobster fishing relative to current management. By accounting for spatial variation in the impacts of coastal and ocean activities on benefits that ecosystems provide to people, our models allowed stakeholders and policymakers to refine zones of human use. The final version of the preferred plan improved expected coastal protection by >25% and more than doubled the revenue from fishing, compared with earlier versions based on stakeholder preferences alone. Including outcomes in terms of ecosystem-service supply and value allowed for explicit consideration of multiple benefits from oceans and coasts that typically are evaluated separately in management decisions.

Current status and future prospects for the assessment of marine and coastal ecosystem services: a systematic review.

Science.gov (United States)

Liquete, Camino; Piroddi, Chiara; Drakou, Evangelia G; Gurney, Leigh; Katsanevakis, Stelios; Charef, Aymen; Egoh, Benis

2013-01-01

Research on ecosystem services has grown exponentially during the last decade. Most of the studies have focused on assessing and mapping terrestrial ecosystem services highlighting a knowledge gap on marine and coastal ecosystem services (MCES) and an urgent need to assess them. We reviewed and summarized existing scientific literature related to MCES with the aim of extracting and classifying indicators used to assess and map them. We found 145 papers that specifically assessed marine and coastal ecosystem services from which we extracted 476 indicators. Food provision, in particular fisheries, was the most extensively analyzed MCES while water purification and coastal protection were the most frequently studied regulating and maintenance services. Also recreation and tourism under the cultural services was relatively well assessed. We highlight knowledge gaps regarding the availability of indicators that measure the capacity, flow or benefit derived from each ecosystem service. The majority of the case studies was found in mangroves and coastal wetlands and was mainly concentrated in Europe and North America. Our systematic review highlighted the need of an improved ecosystem service classification for marine and coastal systems, which is herein proposed with definitions and links to previous classifications. This review summarizes the state of available information related to ecosystem services associated with marine and coastal ecosystems. The cataloging of MCES indicators and the integrated classification of MCES provided in this paper establish a background that can facilitate the planning and integration of future assessments. The final goal is to establish a consistent structure and populate it with information able to support the implementation of biodiversity conservation policies.

Experimental and numerical analysis of coastal protection provided by natural ecosystems

Science.gov (United States)

Maza, M.; Lara, J. L.; Losada, I. J.; Nepf, H. M.

2016-12-01

The risk of flooding and erosion is increasing for many coastal areas owing to global and regional changes in climate conditions together with increasing exposure and vulnerability. After hurricane Katrina (2005) and Sandy (2012) and the tsunami in Indonesia (2004), coastal managers have become interested in low environmental impact alternatives, or nature-based solutions, to protect the coast. Although capacity for coastal ecosystems to damp flow energy has been widely recognized, they have not been firmly considered in the portfolio of coastal protection options. This is mainly due to the complexity of flow-vegetation interaction and of quantifying the value of coastal protection provided by these ecosystems. This complex problem involves different temporal and spatial scales and disciplines, such as engineering, ecology and economics. This work aims to make a step forward in better understanding the physics involved in flow-vegetation interaction leading to new formulations and parameterizations to address some unsolved questions in literature: the representation of plants and field properties; the influence of wave parameters on the relevant processes; the role of the combined effect of waves and currents and the effect of extreme events on vegetation elements. The three main coastal vegetated ecosystems (seagrasses, saltmarshes and mangroves) are studied with an experimental and numerical approach. Experimental analysis is carried out using mimics and real vegetation, considering different flow and vegetation parameters and characterizing flow energy attenuation for the different scenarios. Numerical simulations are performed using 2-D and 3-D Navier-Stokes models in which the effect of vegetation is implemented and validated. These models are used to extend experimental results by simulating different vegetation distributions and analyzing variables such as high-spatial-resolution free surface and velocity data and forces exerted on vegetation elements.

Variability of Iberian upwelling implied by ERA-40 and ERA-Interim reanalyses

Directory of Open Access Journals (Sweden)

José M. R. Alves

2013-05-01

Full Text Available The Regional Ocean Modeling System ocean model is used to simulate the decadal evolution of the regional waters in offshore Iberia in response to atmospheric fields given by ECMWF ERA-40 (1961–2001 and ERA-Interim (1989–2008 reanalyses. The simulated sea surface temperature (SST fields are verified against satellite AVHRR SST, and they are analysed to characterise the variability and trends of coastal upwelling in the region. Opposing trends in upwelling frequency are found at the northern limit, where upwelling has been decreasing in recent decades, and at its southern edge, where there is some evidence of increased upwelling. These results confirm previous observational studies and, more importantly, indicate that observed SST trends are not only due to changes in radiative or atmospheric heat fluxes alone but also due to changes in upwelling dynamics, suggesting that such a process may be relevant in climate change scenarios.

Ecosystem-based management of coastal eutrophication

DEFF Research Database (Denmark)

Andersen, Jesper H.

This thesis focuses on Ecosystem-Based Management (EBM) of coastal eutrophication. Special attention is put on connections between science and decision-making in regard to development, implementation and revision of evidence-based nutrient management strategies. Two strategies are presented...... and analysed: the Danish Action Plans on the Aquatic Environment and the eutrophication segment of the Baltic Sea Action Plan. Similarities and differences are discussed and elements required for making nutrient management strategies successful are suggested. Key words: Eutrophication, marine, Danish...

Influence of glacier runoff on ecosystem structure in Gulf of Alaska fjords

Science.gov (United States)

Arimitsu, Mayumi L.; Piatt, John F.; Mueter, Franz J.

2016-01-01

To better understand the influence of glacier runoff on fjord ecosystems, we sampled oceanographic conditions, nutrients, zooplankton, forage fish and seabirds within 4 fjords in coastal areas of the Gulf Alaska. We used generalized additive models and geostatistics to identify the range of glacier runoff influence into coastal waters within fjords of varying estuarine influence and topographic complexity. We also modeled the response of depth-integrated chlorophyll a concentration, copepod biomass, fish and seabird abundance to physical, nutrient and biotic predictor variables. The effects of glacial runoff were traced at least 10 km into coastal fjords by cold, turbid, stratified and generally nutrient-rich near-surface conditions. Glacially modified physical gradients, nutrient availability and among-fjord differences explained 67% of the variation in phytoplankton abundance, which is a driver of ecosystem structure at higher trophic levels. Copepod, euphausiid, fish and seabird distribution and abundance were related to environmental gradients that could be traced to glacial freshwater input, particularly turbidity and temperature. Seabird density was predicted by prey availability and silicate concentrations, which may be a proxy for upwelling areas where this nutrient is in excess. Similarities in ecosystem structure among fjords were attributable to an influx of cold, fresh and sediment-laden water, whereas differences were likely related to fjord topography and local differences in estuarine vs. ocean influence. We anticipate that continued changes in the timing and volume of glacial runoff will ultimately alter coastal ecosystems in the future.

Changes in upwelling and surface productivity in the Eastern Pacific during Terminations I and II

Science.gov (United States)

Erdem, Z.; De Bar, M.; Stolwijk, D.; Schneider, R. R.; S Sinninghe Damsté, J.; Schouten, S.

2017-12-01

The Eastern Pacific coastal system is characterized by intense upwelling and consequently by an enhanced surface primary productivity. Combination of this high organic matter flux with sluggish bottom water ventilation results in one of the most pronounced oxygen minimum zones reaching from offshore California in the North to offshore Chile in the South. As a result of this process, the region is particularly interesting in view of nutrient and carbon cycling as well as ecosystem dynamics. The dynamics of the upwelling and oxygen concentrations are closely related to climatic conditions. Therefore, paleo-reconstructions of different settings are crucial in order to improve our understanding of the response of these nutrient-rich, oxygen-deficient, environments in relation to the recent global ocean warming, acidification and deoxygenation. In this study, we present downcore results from three different sites in the Eastern Pacific: offshore California (IODP site 1012), Peru (M77/2-52-2) and Chile (IODP site 1234). We applied different biomarkers as proxies to decipher changes in phytoplankton community composition, including the upwelling index based on long chain diols, and other common productivity indicators such as bulk organic carbon, carbonate and biogenic opal. In addition, application of carbon and nitrogen isotope ratios of total organic carbon and benthic foraminifera complement our multiproxy approach. Herewith we aim to compare at least two glacial-interglacial transitions with different magnitudes of deglacial warming along the Eastern Pacific upwelling systems at different latitudes. The data presented will cover the last 160 ka BP offshore California and Chile, and 30 ka BP offshore Peru enabling comparison between glacial Terminations I and II.

Coastal biodiversity and ecosystem services flows at the landscape scale: The CBESS progamme.

Science.gov (United States)

Paterson, David; Bothwell, John; Bradbury, Richard; Burrows, Michael; Burton, Niall; Emmerson, Mark; Garbutt, Angus; Skov, Martin; Solan, Martin; Spencer, Tom; Underwood, Graham

2015-04-01

The health of the European coastline is inextricably linked to the economy and culture of coastal nations but they are sensitive to climate change. As global temperatures increase, sea levels will rise and the forces experienced where land meets sea will become more destructive. Salt marshes, mudflats, beaches will be affected. These landscapes support a wide range of economically valuable animal and plant species, but also act as sites of carbon storage, nutrient recycling, and pollutant capture and amelioration. Their preservation is of utmost importance. Our programme: "A hierarchical approach to the examination of the relationship between biodiversity and ecosystem service flows across coastal margins" (CBESS) is designed to understand the landscape-scale links between the functions that these systems provide (ecosystem service flows) and the organisms that provide these services (biodiversity stocks) and moves beyond most previous studies, conducted at smaller scales. Our consortium of experts ranges from microbial ecologists, through environmental economists, to mathematical modellers, and organisations (RSPB, BTO, CEFAS, EA) with vested interest in the sustainable use of coastal wetlands. CBESS spans the landscape scale, investigating how biodiversity stocks provide ecosystem services (cf. National Ecosystem Assessment: Supporting services; Provisioning services; Regulating services; and Cultural services). CBESS combined a detailed study of two regional landscapes with a broad-scale UK-wide study to allow both specific and general conclusions to be drawn. The regional study compares two areas of great UK national importance: Morecambe Bay on the west coast and the Essex coastline on the east. We carried out biological and physical surveys at more than 600 stations combined with in situ measures of ecosystem funtction to clarify how biodiversity can provide these important ecosystem functions across scales. This information will be shared with those

Current Status and Future Prospects for the Assessment of Marine and Coastal Ecosystem Services: A Systematic Review

Science.gov (United States)

Liquete, Camino; Piroddi, Chiara; Drakou, Evangelia G.; Gurney, Leigh; Katsanevakis, Stelios; Charef, Aymen; Egoh, Benis

2013-01-01

Background Research on ecosystem services has grown exponentially during the last decade. Most of the studies have focused on assessing and mapping terrestrial ecosystem services highlighting a knowledge gap on marine and coastal ecosystem services (MCES) and an urgent need to assess them. Methodology/Principal Findings We reviewed and summarized existing scientific literature related to MCES with the aim of extracting and classifying indicators used to assess and map them. We found 145 papers that specifically assessed marine and coastal ecosystem services from which we extracted 476 indicators. Food provision, in particular fisheries, was the most extensively analyzed MCES while water purification and coastal protection were the most frequently studied regulating and maintenance services. Also recreation and tourism under the cultural services was relatively well assessed. We highlight knowledge gaps regarding the availability of indicators that measure the capacity, flow or benefit derived from each ecosystem service. The majority of the case studies was found in mangroves and coastal wetlands and was mainly concentrated in Europe and North America. Our systematic review highlighted the need of an improved ecosystem service classification for marine and coastal systems, which is herein proposed with definitions and links to previous classifications. Conclusions/Significance This review summarizes the state of available information related to ecosystem services associated with marine and coastal ecosystems. The cataloging of MCES indicators and the integrated classification of MCES provided in this paper establish a background that can facilitate the planning and integration of future assessments. The final goal is to establish a consistent structure and populate it with information able to support the implementation of biodiversity conservation policies. PMID:23844080

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...

A spatial analysis of cultural ecosystem service valuation by regional stakeholders in Florida: a coastal application of the social values for ecosystem services (SolVES) tool

Science.gov (United States)

Coffin, Alisa W.; Swett, Robert A.; Cole, Zachary D.

2012-01-01

Livelihoods and lifestyles of people throughout the world depend on essential goods and services provided by marine and coastal ecosystems. However, as societal demand increases and available ocean and coastal space diminish, better methods are needed to spatially and temporally allocate ocean and coastal activities such as shipping, energy production, tourism, and fishing. While economic valuation is an important mechanism for doing so, cultural ecosystem services often do not lend themselves to this method. Researchers from the U.S. Geological Survey are working collaboratively with the Florida Sea Grant College Program to map nonmonetary values of cultural ecosystem services for a pilot area (Sarasota Bay) in the Gulf of Mexico. The research seeks to close knowledge gaps about the attitudes and perceptions, or nonmonetary values, held by coastal residents toward cultural ecosystem services, and to adapt related, terrestrial-based research methods to a coastal setting. A critical goal is to integrate research results with coastal and marine spatial planning applications, thus making them relevant to coastal planners and managers in their daily efforts to sustainably manage coastal resources. Using information about the attitudes and preferences of people toward places and uses in the landscape, collected from value and preference surveys, the USGS SolVES 2.0 tool will provide quantitative models to relate social values, or perceived nonmonetary values, assigned to locations by survey respondents with the underlying environmental characteristics of those same locations. Project results will increase scientific and geographic knowledge of how Sarasota Bay residents value their area’s cultural ecosystem services.

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.

Concepts and theoretical specifications of a Coastal Vulnerability Dynamic Simulator (COVUDS): A multi-agent system for simulating coastal vulnerability towards management of coastal ecosystem services

Science.gov (United States)

Orencio, P. M.; Endo, A.; Taniguchi, M.

2014-12-01

Disaster-causing natural hazards such as floods, erosions, earthquakes or slope failures were particularly observed to be concentrated in certain geographical regions. In the Asia-pacific region, coastal ecosystems were suffering because of perennial threats driven by chronic fluctuations in climate variability (e.g., typhoons, ENSO), or by dynamically occurring events (e.g., earthquakes, tsunamis). Among the many people that were found prone to such a risky condition were the ones inhabiting near the coastal areas. Characteristically, aside from being located at the forefront of these events, the coastal communities have impacted the resource by the kind of behavioral patterns they exhibited, such as overdependence and overexploitation to achieve their wellbeing. In this paper, we introduce the development of an approach to an assessment of the coupled human- environment using a multi- agent simulation (MAS) model known as Coastal Vulnerability Dynamic Simulator (COVUDS). The COVUDS comprised a human- environmental platform consisting multi- agents with corresponding spatial- based dynamic and static variables. These variables were used to present multiple hypothetical future situations that contribute to the purpose of supporting a more rational management of the coastal ecosystem and their environmental equities. Initially, we present the theoretical and conceptual components that would lead to the development of the COVUDS. These consisted of the human population engaged in behavioral patterns affecting the conditions of coastal ecosystem services; the system of the biophysical environment and changes in patches brought by global environment and local behavioral variations; the policy factors that were important for choosing area- specific interventions; and the decision- making mechanism that integrates the first three components. To guide a future scenario-based application that will be undertaken in a coastal area in the Philippines, the components of the

Spatial distribution of upwelling off the central east coast of India

Digital Repository Service at National Institute of Oceanography (India)

Rao, T.V.N.

of the data collected along the five sections. At all the sections, a decrease in water temperature and an increase in salinity from the offshore stations to the stations closest to the shore indicated coastal upwelling. The Rossby radii of deformation...

Impact of Equatorial Waves on the Variability of Upwelling Process Along West Coast of India

Science.gov (United States)

Prakash, K. R.; Nigam, T.; Pant, V.

2017-12-01

Coastal upwelling is a seasonal phenomenon along the south eastern Arabian Sea (SEAS) due to favourable wind setup during Indian Summer Monsoon Season (June-September). This upwelling brings subsurface cold and nutrient rich water to the surface layers. The cold water transported northward by the altered along shore current of west coast of India in the post-monsoon season. The different climatological forcing of positive Indian Ocean Dipole (IOD) and normal years were utilised to simulate the upwelling off the west coast of India using a three dimensional Regional Ocean Modelling System (ROMS). Strength of upwelling and the northward transport were found to be weaken for positive IOD simulations as compared to normal years. Analysis suggests that the meridional wind stress weakening resulted into a decrease in strength of West India Coastal Current (WICC) and, therefore, reduced magnitude of offshore Ekman transport. The mixed layer heat budget calculation also supports the findings by showing dominated vertical process in comparison to net heat flux effect. The post-monsoon northward transport of cold water was found to be correlated with the coastally trapped downwelling Kelvin waves. These waves are the only remote forcing from the Bay of Bengal that reaches to the south-eastern Arabian Sea during the months of October-December. The composite of sea surface height anomalies for the positive IOD and normal years shows that the downwelling Kelwin wave was absent during October-December.

Insights into the Microbial and Viral Dynamics of a Coastal Downwelling-Upwelling Transition.

Directory of Open Access Journals (Sweden)

Gustavo Bueno Gregoracci

Full Text Available Although previous studies have described opposing states in upwelling regions, i.e., the rise of cold nutrient-rich waters and prevalence of surface warm nutrient-poor waters, few have addressed the transition from one state to the other. This study aimed to describe the microbial and viral structure during this transition and was able to obtain the taxonomic and metabolic compositions as well as physical-chemical data. This integrated approach allowed for a better understanding of the dynamics of the downwelling upwelling transition, suggesting that a wealth of metabolic processes and ecological interactions are occurring in the minute fractions of the plankton (femto, pico, nano. These processes and interactions included evidence of microbial predominance during downwelling (with nitrogen recycling and aerobic anoxygenic photosynthesis, different viral predation pressures over primary production in different states (cyanobacteria vs eukaryotes, and a predominance of diatoms and selected bacterial and archaeal groups during upwelling (with the occurrence of a wealth of nitrogen metabolism involving ammonia. Thus, the results provided insights into which microbes, viruses and microbial-mediated processes are probably important in the functioning of upwelling systems.

Informing policy to protect coastal coral reefs: insight from a global review of reducing agricultural pollution to coastal ecosystems.

Science.gov (United States)

Kroon, Frederieke J; Schaffelke, Britta; Bartley, Rebecca

2014-08-15

The continuing degradation of coral reefs has serious consequences for the provision of ecosystem goods and services to local and regional communities. While climate change is considered the most serious risk to coral reefs, agricultural pollution threatens approximately 25% of the total global reef area with further increases in sediment and nutrient fluxes projected over the next 50 years. Here, we aim to inform coral reef management using insights learned from management examples that were successful in reducing agricultural pollution to coastal ecosystems. We identify multiple examples reporting reduced fluxes of sediment and nutrients at end-of-river, and associated declines in nutrient concentrations and algal biomass in receiving coastal waters. Based on the insights obtained, we recommend that future protection of coral reef ecosystems demands policy focused on desired ecosystem outcomes, targeted regulatory approaches, up-scaling of watershed management, and long-term maintenance of scientifically robust monitoring programs linked with adaptive management. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Preliminary analysis of the Jimo coastal ecosystem with the ecopath model

Science.gov (United States)

Su, Meng

2016-12-01

The Jimo coast encompasses an area of 2157 km2, and the ecosystem is valuable both socially and economically with regional fisheries substantially contributing to the value. A mass-balanced trophic model consisting of 15 functional ecological groups was developed for the coastal ecosystem using the Ecopath model in Ecopath with Ecosim (EwE) software (version 6.4.3). The results of the model simulations indicated that the trophic levels of the functional groups varied between 1.0 and 3.76, and the total production of the system was estimated to be 5112.733 t km-2 yr-1 with a total energy transfer efficiency of 17.6%. The proportion of the total flow originating from detritus was estimated to be 48%, whereas that from primary producers was 52%, indicating that the grazing food chain dominated the energy flow. The ratio of total primary productivity to total respiration in the system was 3.78, and the connectivity index was 0.4. The fin cycling index and the mean path length of the energy flow were 4.92% and 2.57%, respectively, which indicated that the ecosystem exhibits relatively low maturity and stability. The mixed trophic impact (MTI) procedure suggested that the ecological groups at lower trophic levels dominated the feeding dynamics in the Jimo coastal ecosystem. Overfishing is thought to be the primary reason for the degeneration of the Jimo coastal ecosystem, resulting in a decline in the abundance of pelagic and demersal fish species and a subsequent shift to the predominance of lower-trophic-level functional groups. Finally, we offered some recommendations for improving current fishery management practices.

Satellite observation of bio-optical indicators related to North-Western Black Sea coastal zone changes

Science.gov (United States)

Zoran, Maria

Satellite remote sensing provides a means for locating, identifying and mapping certain coastal zone features and assessing of spatio-temporal changes.The Romanian coastal zone of the Black Sea is a mosaic of complex, interacting ecosystems, exposed to dramatic changes due to natural and anthropogenic causes (increase in the nutrient and pollutant load of rivers input, industrial and municipal wastewater pollution along the coast, and dumping on the open sea). This study focuses on the assessment of coastal zone land cover changes based on the fusion of satellite remote sensing data.The evaluation of coastal zone landscapes is based upon different sub-functions which refer to landscape features such as water, soil, land-use, buildings, groundwater, biotope types. Mixed pixels result when the sensor's instantaneous field-of-view includes more than one land cover class on the ground. Based on different satellite data (Landsat TM, ETM, SAR ERS, IKONOS, Quickbird, and MODIS) was performed object recognition for North-Western Black Sea coastal zone. Preliminary results show significant coastline position changes of North Western Black Sea during the period of 1987-2007 and urban growth of Constantza town. Also the change in the position of the coastline is examined and linked to the urban expansion in order to determine if the changes are natural or anthropogenic. A distinction is made between landfill/sedimentation processes on the one hand and dredging/erosion processes on the other. Waves play an important role for shoreline configuration. Wave pattern could induce erosion and sedimentation. A quasi-linear model was used to model the rate of shoreline change. The vectors of shoreline were used to compare with wave spectra model in order to examine the accuracy of the coastal erosion model. The shoreline rate modeled from vectors data of SAR ERS-1 has a good correlation with a quasi-linear model. Wave refraction patterns are a good index for shoreline erosion. A coast

Rising synchrony controls western North American ecosystems

Science.gov (United States)

Black, Bryan A.; van der Sleen, Peter; Di Lorenzo, Emanuele; Griffin, Daniel; Sydeman, William J.; Dunham, Jason B.; Rykaczewski, Ryan R.; Garcia-Reyes, Marisol; Safeeq, Mohammad; Arismendi, Ivan; Bograd, Steven J.

2018-01-01

Along the western margin of North America, the winter expression of the North Pacific High (NPH) strongly influences interannual variability in coastal upwelling, storm track position, precipitation, and river discharge. Coherence among these factors induces covariance among physical and biological processes across adjacent marine and terrestrial ecosystems. Here, we show that over the past century the degree and spatial extent of this covariance (synchrony) has substantially increased, and is coincident with rising variance in the winter NPH. Furthermore, centuries‐long blue oak (Quercus douglasii) growth chronologies sensitive to the winter NPH provide robust evidence that modern levels of synchrony are among the highest observed in the context of the last 250 years. These trends may ultimately be linked to changing impacts of the El Niño Southern Oscillation on mid‐latitude ecosystems of North America. Such a rise in synchrony may destabilize ecosystems, expose populations to higher risks of extinction, and is thus a concern given the broad biological relevance of winter climate to biological systems.

Mechanisms and risk of cumulative impacts to coastal ecosystem services: An expert elicitation approach

KAUST Repository

Singh, Gerald G.; Sinner, Jim; Ellis, Joanne; Kandlikar, Milind; Halpern, Benjamin S.; Satterfield, Terre; Chan, Kai M.A.

2017-01-01

Coastal environments are some of the most populated on Earth, with greater pressures projected in the future. Managing coastal systems requires the consideration of multiple uses, which both benefit from and threaten multiple ecosystem services

Payments for coastal and marine ecosystem services: prospects and principles

Energy Technology Data Exchange (ETDEWEB)

Mohammed, Essam Yassin

2012-05-15

Coastal and marine resources provide millions of impoverished people across the global South with livelihoods, and provide the world with a range of critical 'ecosystem services', from biodiversity and culture to carbon storage and flood protection. Yet across the world, these resources are fast-diminishing under the weight of pollution, land clearance, coastal development, overfishing, natural disasters and climate change. Traditional approaches to halt the decline focus on regulating against destructive practices, but to little effect. A more successful strategy could be to establish payments for ecosystem services (PES) schemes, or incorporate an element of PES in existing regulatory mechanisms. Examples from across the world suggest that PES can work to protect both livelihoods and environments. But to succeed, these schemes must be underpinned by robust research, clear property rights, equitable benefit sharing and sustainable finance.

Coastal Fog Sustains Summer Baseflow in Northern Californian Watershed

Science.gov (United States)

Chung, M.; Dufour, A.; Leonardson, R.; Thompson, S. E.; Dawson, T. E.

2015-12-01

The Mediterranean climate of Northern California imposes significant water stress on ecosystems and water resources during the dry summer months. During summer, frequently the only water inputs occur as occult precipitation, in the form of fog and dew. In this study, we characterized the role of coastal fog, a dominant feature of Northern Californian coastal ecosystems and a widespread phenomenon associated with deep marine upwelling in west coast, arid, and Mediterranean climates worldwide. We monitored fog occurrence and intensity, throughfall following canopy interception of fog, soil moisture, streamflow, and meteorological variables, and made visual observations of the spatial extent of fog using time-lapse imagery in Upper Pilarcitos Creek Watershed (managed by San Francisco Public Utilities Commission as part of the San Francisco area water supply). We adopted a stratified sampling design that captured the watershed's elevation gradient, forest-edge versus interior locations, and different vegetation cover. The point-scale observations of throughfall inputs and transpiration suppression, estimated from the Penman equation, were upscaled using such watershed features and the observed fog "footprint" identified from the time-lapse images. When throughfall input and fog-induced transpiration suppression were incorporated into the operational watershed model, they improved estimates of summer baseflow, which remained persistently higher than could be explained without the fog effects. Fog, although providing relatively small volumetric inputs to the water balance, appears to offer significant relief of water stress throughout the terrestrial and aquatic components of the coastal Californian ecosystem and thus should be accounted for when assessing water stress availability in dry ecosystems.

Ecosystem services provided by a complex coastal region: challenges of classification and mapping

Science.gov (United States)

Sousa, Lisa P.; Sousa, Ana I.; Alves, Fátima L.; Lillebø, Ana I.

2016-03-01

A variety of ecosystem services classification systems and mapping approaches are available in the scientific and technical literature, which needs to be selected and adapted when applied to complex territories (e.g. in the interface between water and land, estuary and sea). This paper provides a framework for addressing ecosystem services in complex coastal regions. The roadmap comprises the definition of the exact geographic boundaries of the study area; the use of CICES (Common International Classification of Ecosystem Services) for ecosystem services identification and classification; and the definition of qualitative indicators that will serve as basis to map the ecosystem services. Due to its complexity, the Ria de Aveiro coastal region was selected as case study, presenting an opportunity to explore the application of such approaches at a regional scale. The main challenges of implementing the proposed roadmap, together with its advantages are discussed in this research. The results highlight the importance of considering both the connectivity of natural systems and the complexity of the governance framework; the flexibility and robustness, but also the challenges when applying CICES at regional scale; and the challenges regarding ecosystem services mapping.

Ecosystem services provided by a complex coastal region: challenges of classification and mapping.

Science.gov (United States)

Sousa, Lisa P; Sousa, Ana I; Alves, Fátima L; Lillebø, Ana I

2016-03-11

A variety of ecosystem services classification systems and mapping approaches are available in the scientific and technical literature, which needs to be selected and adapted when applied to complex territories (e.g. in the interface between water and land, estuary and sea). This paper provides a framework for addressing ecosystem services in complex coastal regions. The roadmap comprises the definition of the exact geographic boundaries of the study area; the use of CICES (Common International Classification of Ecosystem Services) for ecosystem services identification and classification; and the definition of qualitative indicators that will serve as basis to map the ecosystem services. Due to its complexity, the Ria de Aveiro coastal region was selected as case study, presenting an opportunity to explore the application of such approaches at a regional scale. The main challenges of implementing the proposed roadmap, together with its advantages are discussed in this research. The results highlight the importance of considering both the connectivity of natural systems and the complexity of the governance framework; the flexibility and robustness, but also the challenges when applying CICES at regional scale; and the challenges regarding ecosystem services mapping.

Climate change and ocean deoxygenation within intensified surface-driven upwelling circulations.

Science.gov (United States)

Bakun, Andrew

2017-09-13

Ocean deoxygenation often takes place in proximity to zones of intense upwelling. Associated concerns about amplified ocean deoxygenation arise from an arguable likelihood that coastal upwelling systems in the world's oceans may further intensify as anthropogenic climate change proceeds. Comparative examples discussed include the uniquely intense seasonal Somali Current upwelling, the massive upwelling that occurs quasi-continuously off Namibia and the recently appearing and now annually recurring 'dead zone' off the US State of Oregon. The evident 'transience' in causal dynamics off Oregon is somewhat mirrored in an interannual-scale intermittence in eruptions of anaerobically formed noxious gases off Namibia. A mechanistic scheme draws the three examples towards a common context in which, in addition to the obvious but politically problematic remedy of actually reducing 'greenhouse' gas emissions, the potentially manageable abundance of strongly swimming, finely gill raker-meshed small pelagic fish emerges as a plausible regulating factor.This article is part of the themed issue 'Ocean ventilation and deoxygenation in a warming world'. © 2017 The Author(s).

Study on water quality around mangrove ecosystem for coastal rehabilitation

Science.gov (United States)

Guntur, G.; Sambah, A. B.; Arisandi, D. M.; Jauhari, A.; Jaziri, A. A.

2018-01-01

Coastal ecosystems are vulnerable to environmental degradation including the declining water quality in the coastal environment due to the influence of human activities where the river becomes one of the input channels. Some areas in the coastal regions of East Java directly facing the Madura Strait indicate having experienced the environmental degradation, especially regarding the water quality. This research was conducted in the coastal area of Probolinggo Regency, East Java, aiming to analyze the water quality as the basis for coastal rehabilitation planning. This study was carried out using survey and observation methods. Water quality measurement results were analyzed conforming to predetermined quality standards. The coastal area rehabilitation planning as a means to restore the degraded water quality parameters is presumably implemented through mangrove planting. Thus, the mangrove mapping was also devised in this research. Based on 40 sampling points, the results illustrate that according to the quality standard, the water quality in the study area is likely to be deteriorated. On account of the mapping analysis of mangrove distribution in the study area, the rehabilitation of the coastal zone can be done through planning the mangrove forest plantation. The recommended coastal area maintenance is a periodic water quality observation planning in the river region which is divided into three zones to monitor the impact of fluctuating changes in land use or human activities on the coastal water quality.

Mechanisms and risk of cumulative impacts to coastal ecosystem services: An expert elicitation approach.

Science.gov (United States)

Singh, Gerald G; Sinner, Jim; Ellis, Joanne; Kandlikar, Milind; Halpern, Benjamin S; Satterfield, Terre; Chan, Kai M A

2017-09-01

Coastal environments are some of the most populated on Earth, with greater pressures projected in the future. Managing coastal systems requires the consideration of multiple uses, which both benefit from and threaten multiple ecosystem services. Thus understanding the cumulative impacts of human activities on coastal ecosystem services would seem fundamental to management, yet there is no widely accepted approach for assessing these. This study trials an approach for understanding the cumulative impacts of anthropogenic change, focusing on Tasman and Golden Bays, New Zealand. Using an expert elicitation procedure, we collected information on three aspects of cumulative impacts: the importance and magnitude of impacts by various activities and stressors on ecosystem services, and the causal processes of impact on ecosystem services. We assessed impacts to four ecosystem service benefits - fisheries, shellfish aquaculture, marine recreation and existence value of biodiversity-addressing three main research questions: (1) how severe are cumulative impacts on ecosystem services (correspondingly, what potential is there for restoration)?; (2) are threats evenly distributed across activities and stressors, or do a few threats dominate?; (3) do prominent activities mainly operate through direct stressors, or do they often exacerbate other impacts? We found (1) that despite high uncertainty in the threat posed by individual stressors and impacts, total cumulative impact is consistently severe for all four ecosystem services. (2) A subset of drivers and stressors pose important threats across the ecosystem services explored, including climate change, commercial fishing, sedimentation and pollution. (3) Climate change and commercial fishing contribute to prominent indirect impacts across ecosystem services by exacerbating regional impacts, namely sedimentation and pollution. The prevalence and magnitude of these indirect, networked impacts highlights the need for approaches

Mechanisms and risk of cumulative impacts to coastal ecosystem services: An expert elicitation approach

KAUST Repository

Singh, Gerald G.

2017-05-23

Coastal environments are some of the most populated on Earth, with greater pressures projected in the future. Managing coastal systems requires the consideration of multiple uses, which both benefit from and threaten multiple ecosystem services. Thus understanding the cumulative impacts of human activities on coastal ecosystem services would seem fundamental to management, yet there is no widely accepted approach for assessing these. This study trials an approach for understanding the cumulative impacts of anthropogenic change, focusing on Tasman and Golden Bays, New Zealand. Using an expert elicitation procedure, we collected information on three aspects of cumulative impacts: the importance and magnitude of impacts by various activities and stressors on ecosystem services, and the causal processes of impact on ecosystem services. We assessed impacts to four ecosystem service benefits — fisheries, shellfish aquaculture, marine recreation and existence value of biodiversity—addressing three main research questions: (1) how severe are cumulative impacts on ecosystem services (correspondingly, what potential is there for restoration)?; (2) are threats evenly distributed across activities and stressors, or do a few threats dominate?; (3) do prominent activities mainly operate through direct stressors, or do they often exacerbate other impacts? We found (1) that despite high uncertainty in the threat posed by individual stressors and impacts, total cumulative impact is consistently severe for all four ecosystem services. (2) A subset of drivers and stressors pose important threats across the ecosystem services explored, including climate change, commercial fishing, sedimentation and pollution. (3) Climate change and commercial fishing contribute to prominent indirect impacts across ecosystem services by exacerbating regional impacts, namely sedimentation and pollution. The prevalence and magnitude of these indirect, networked impacts highlights the need for

Patterns of Arbuscular Mycorrhizal Fungal Distribution on Mainland and Island Sandy Coastal Plain Ecosystems in Brazil.

Science.gov (United States)

da Silva, Iolanda Ramalho; de Souza, Francisco Adriano; da Silva, Danielle Karla Alves; Oehl, Fritz; Maia, Leonor Costa

2017-10-01

Although sandy coastal plains are important buffer zones to protect the coast line and maintain biological diversity and ecosystem services, these ecosystems have been endangered by anthropogenic activities. Thus, information on coastal biodiversity and forces shaping coastal biological diversity are extremely important for effective conservation strategies. In this study, we aimed to compare arbuscular mycorrhizal (AM) fungal communities from soil samples collected on the mainland and nearby islands located in Brazilian sandy coastal plain ecosystems (Restingas) to get information about AM fungal biogeography and identify factors shaping these communities. Soil samples were collected in 2013 and 2014 on the beachfront of the tropical sandy coastal plain at six sites (three island and three mainland locations) across the northeast, southeast, and south regions of Brazil. Overall, we recorded 53 AM fungal species from field and trap culture samples. The richness and diversity of AM fungal species did not differ between mainland and island locations, but AM fungal community assemblages were different between mainland and island environments and among most sites sampled. Glomeromycota communities registered from island samples showed higher heterogeneity than communities from mainland samples. Sandy coastal plains harbor diverse AM fungal communities structured by climatic, edaphic, and spatial factors, while the distance from the colonizing source (mainland environments) does not strongly affect the AM fungal communities in Brazilian coastal environments.

Marine ecosystem modeling beyond the box: using GIS to study carbon fluxes in a coastal ecosystem.

Science.gov (United States)

Wijnbladh, Erik; Jönsson, Bror Fredrik; Kumblad, Linda

2006-12-01

Studies of carbon fluxes in marine ecosystems are often done by using box model approaches with basin size boxes, or highly resolved 3D models, and an emphasis on the pelagic component of the ecosystem. Those approaches work well in the ocean proper, but can give rise to considerable problems when applied to coastal systems, because of the scale of certain ecological niches and the fact that benthic organisms are the dominant functional group of the ecosystem. In addition, 3D models require an extensive modeling effort. In this project, an intermediate approach based on a high resolution (20x20 m) GIS data-grid has been developed for the coastal ecosystem in the Laxemar area (Baltic Sea, Sweden) based on a number of different site investigations. The model has been developed in the context of a safety assessment project for a proposed nuclear waste repository, in which the fate of hypothetically released radionuclides from the planned repository is estimated. The assessment project requires not only a good understanding of the ecosystem dynamics at the site, but also quantification of stocks and flows of matter in the system. The data-grid was then used to set up a carbon budget describing the spatial distribution of biomass, primary production, net ecosystem production and thus where carbon sinks and sources are located in the area. From these results, it was clear that there was a large variation in ecosystem characteristics within the basins and, on a larger scale, that the inner areas are net producing and the outer areas net respiring, even in shallow phytobenthic communities. Benthic processes had a similar or larger influence on carbon fluxes as advective processes in inner areas, whereas the opposite appears to be true in the outer basins. As many radionuclides are expected to follow the pathways of organic matter in the environment, these findings enhance our abilities to realistically describe and predict their fate in the ecosystem.

Marine Ecosystem Modeling Beyond the Box: Using GIS to Study Carbon Fluxes in a Coastal Ecosystem

International Nuclear Information System (INIS)

Wijnbladh, Erik; Joensson, Bror Fredrik; Kumblad, Linda

2006-01-01

Studies of carbon fluxes in marine ecosystems are often done by using box model approaches with basin size boxes, or highly resolved 3D models, and an emphasis on the pelagic component of the ecosystem. Those approaches work well in the ocean proper, but can give rise to considerable problems when applied to coastal systems, because of the scale of certain ecological niches and the fact that benthic organisms are the dominant functional group of the ecosystem. In addition, 3D models require an extensive modeling effort. In this project, an intermediate approach based on a high resolution (20x20 m) GIS data-grid has been developed for the coastal ecosystem in the Laxemar area (Baltic Sea, Sweden) based on a number of different site investigations. The model has been developed in the context of a safety assessment project for a proposed nuclear waste repository, in which the fate of hypothetically released radionuclides from the planned repository is estimated. The assessment project requires not only a good understanding of the ecosystem dynamics at the site, but also quantification of stocks and flows of matter in the system. The data-grid was then used to set up a carbon budget describing the spatial distribution of biomass, primary production, net ecosystem production and thus where carbon sinks and sources are located in the area. From these results, it was clear that there was a large variation in ecosystem characteristics within the basins and, on a larger scale, that the inner areas are net producing and the outer areas net respiring, even in shallow phyto benthic communities. Benthic processes had a similar or larger influence on carbon fluxes as advective processes in inner areas, whereas the opposite appears to be true in the outer basins. As many radionuclides are expected to follow the pathways of organic matter in the environment, these findings enhance our abilities to realistically describe and predict their fate in the ecosystem

Geostationary Coastal Ecosystem Dynamics Imager (GEO CEDI) for the GEO Coastal and Air Pollution Events (GEO CAPE) Mission. Concept Presentation

Science.gov (United States)

Janz, Scott; Smith, James C.; Mannino, Antonio

2010-01-01

This slide presentation reviews the concepts of the Geostationary Coastal Ecosystem Dynamics Imager (GEO CEDI) which will be used on the GEO Coastal and Air Pollution Events (GEO CAPE) Mission. The primary science requirements require scans of the U.S. Coastal waters 3 times per day during the daylight hours. Included in the overview are presentations about the systems, the optics, the detectors, the mechanical systems, the electromechanical systems, the electrical design, the flight software, the thermal systems, and the contamination prevention requirements.

The physical structure of an upwelling filament off the North-west ...

African Journals Online (AJOL)

... in dispersal of material originating in the region of active coastal upwelling. The location of the filament studied appears repeatable from year to year, suggestive of a strong relation with the topographically trapped eddy, which was situated downstream of a lateral ridge between the. Canary Islands and the African coast.

Environmental changes associated with monsoon induced upwelling, off central west coast of India

Digital Repository Service at National Institute of Oceanography (India)

DeSousa, S.N.; Sawkar, K.; Rao, P.V.S.S.D.P.

in response to prevailing equatorward winds. High salinity ocean waters of rich nutrient contents were observed at the coast in some locations. However, the effect of upwelling on the surface distribution of properties was reduced to some extent due to coastal...

Spatio-temporal variability of upwelling along the southwest coast of India based on satellite observations

Science.gov (United States)

Jayaram, Chiranjivi; Kumar, P. K. Dinesh

2018-03-01

Upwelling phenomenon along the eastern boundaries of global ocean has received greater attention in the recent times due to its environmental and economic significance in the global warming and the scenario of changing climate as opined by IPCC AR5. In this context, the availabile satellite data on sea surface winds, sea surface temperature (SST), sea level anomaly (SLA) and chlorophyll-a concentration (Chl-a), for the period 1981-2016 were analyzed to identify the coastal upwelling pattern in the Southeastern Arabian Sea (SEAS). Synergistic approach, using winds, SST, SLA and Chl-a revealed that strong upwelling was prevailing between 8°N and 12°N. During the study period, geographical differences existed in the peak values of upwelling favorable conditions considered for study. Analysis of the alongshore winds which are conducive for upwelling were observed to be curtailed towards the northern part of the study region between 2005 and 2010. Also, the strength of upwelling reduced during the strong ENSO years of 1997 and 2015. Linear regression based trend analysis of upwelling indices like Ekman transport, SST and chlorophyll along the coast, during the upwelling period, revealed slight increase in the strength towards the southern region while it decreased to the north during the study period.

Ecological Security and Ecosystem Services in Response to Land Use Change in the Coastal Area of Jiangsu, China

Directory of Open Access Journals (Sweden)

Caiyao Xu

2016-08-01

Full Text Available Urbanization, and the resulting land use/cover change, is a primary cause of the degradation of coastal wetland ecosystems. Reclamation projects are seen as a way to strike a balance between socioeconomic development and maintenance of coastal ecosystems. Our aim was to understand the ecological changes to Jiangsu’s coastal wetland resulting from land use change since 1977 by using remote sensing and spatial analyses. The results indicate that: (1 The area of artificial land use expanded while natural land use was reduced, which emphasized an increase in production-orientated land uses at the expense of ecologically important wetlands; (2 It took 34 years for landscape ecological security and 39 years for ecosystem services to regain equilibrium. The coastal reclamation area would recover ecological equilibrium only after a minimum of 30 years; (3 The total ecosystem service value decreased significantly from $2.98 billion per year to $2.31 billion per year from 1977 to 2014. Food production was the only one ecosystem service function that consistently increased, mainly because of government policy; (4 The relationship between landscape ecological security and ecosystem services is complicated, mainly because of the scale effect of landscape ecology. Spatial analysis of changing gravity centers showed that landscape ecological security and ecosystem service quality became better in the north than the south over the study period.

Climate change impacts on U.S. coastal and marine ecosystems

Science.gov (United States)

Scavia, Donald; Field, John C.; Boesch, Donald F.; Buddemeier, Robert W.; Burkett, Virginia; Cayan, Daniel R.; Fogarty, Michael; Harwell, Mark A.; Howarth, Robert W.; Mason, Curt; Reed, Denise J.; Royer, Thomas C.; Sallenger, Asbury H.; Titus, James G.

2002-01-01

Increases in concentrations of greenhouse gases projected for the 21st century are expected to lead to increased mean global air and ocean temperatures. The National Assessment of Potential Consequences of Climate Variability and Change (NAST 2001) was based on a series of regional and sector assessments. This paper is a summary of the coastal and marine resources sector review of potential impacts on shorelines, estuaries, coastal wetlands, coral reefs, and ocean margin ecosystems. The assessment considered the impacts of several key drivers of climate change: sea level change; alterations in precipitation patterns and subsequent delivery of freshwater, nutrients, and sediment; increased ocean temperature; alterations in circulation patterns; changes in frequency and intensity of coastal storms; and increased levels of atmospheric CO2. Increasing rates of sea-level rise and intensity and frequency of coastal storms and hurricanes over the next decades will increase threats to shorelines, wetlands, and coastal development. Estuarine productivity will change in response to alteration in the timing and amount of freshwater, nutrients, and sediment delivery. Higher water temperatures and changes in freshwater delivery will alter estuarine stratification, residence time, and eutrophication. Increased ocean temperatures are expected to increase coral bleaching and higher CO2 levels may reduce coral calcification, making it more difficult for corals to recover from other disturbances, and inhibiting poleward shifts. Ocean warming is expected to cause poleward shifts in the ranges of many other organisms, including commercial species, and these shifts may have secondary effects on their predators and prey. Although these potential impacts of climate change and variability will vary from system to system, it is important to recognize that they will be superimposed upon, and in many cases intensify, other ecosystem stresses (pollution, harvesting, habitat destruction

Long-Distance Interactions Regulate the Structure and Resilience of Coastal Ecosystems

NARCIS (Netherlands)

van de Koppel, J.; van der Heide, T.; Altieri, A.H.; Eriksson, B.K.; Bouma, T.J.; Olff, H.; Silliman, B.R.

2015-01-01

Mounting evidence indicates that spatial interactions are important in structuring coastal ecosystems. Until recently, however, most of this work has been focused on seemingly exceptional systems that are characterized by regular, self-organized patterns. In this review, we document that

Assessing biomass of diverse coastal marsh ecosystems using statistical and machine learning models

Science.gov (United States)

Mo, Yu; Kearney, Michael S.; Riter, J. C. Alexis; Zhao, Feng; Tilley, David R.

2018-06-01

The importance and vulnerability of coastal marshes necessitate effective ways to closely monitor them. Optical remote sensing is a powerful tool for this task, yet its application to diverse coastal marsh ecosystems consisting of different marsh types is limited. This study samples spectral and biophysical data from freshwater, intermediate, brackish, and saline marshes in Louisiana, and develops statistical and machine learning models to assess the marshes' biomass with combined ground, airborne, and spaceborne remote sensing data. It is found that linear models derived from NDVI and EVI are most favorable for assessing Leaf Area Index (LAI) using multispectral data (R2 = 0.7 and 0.67, respectively), and the random forest models are most useful in retrieving LAI and Aboveground Green Biomass (AGB) using hyperspectral data (R2 = 0.91 and 0.84, respectively). It is also found that marsh type and plant species significantly impact the linear model development (P biomass of Louisiana's coastal marshes using various optical remote sensing techniques, and highlights the impacts of the marshes' species composition on the model development and the sensors' spatial resolution on biomass mapping, thereby providing useful tools for monitoring the biomass of coastal marshes in Louisiana and diverse coastal marsh ecosystems elsewhere.

Modelling Ecosystem Dynamics of the Oxygen Minimum Zones in the Angola Gyre and the Northern Benguela Upwelling System.

Science.gov (United States)

Schmidt, M.; Eggert, A.

2016-02-01

The Angola Gyre and the Northern Benguela Upwelling System are two major oxygen minimum zones (OMZ) of different kind connected by the system of African Eastern Boundary Currents. We discuss results from a 3-dimensional coupled biogeochemical model covering both oxygen-deficient systems. The biogeochemical model component comprises trophic levels up to zooplankton. Physiological properties of organisms are parameterized from field data gained mainly in the course of the project "Geochemistry and Ecology of the Namibian Upwelling System" (GENUS). The challenge of the modelling effort is the different nature of both systems. The Angola Gyre, located in a "shadow zone" of the tropical Atlantic, has a low productivity and little ventilation, hence a long residence time of water masses. In the northern Benguela Upwelling System, trade winds drive an intermittent, but permanent nutrient supply into the euphotic zone which fuels a high coastal productivity, large particle export and high oxygen consumption from dissimilatory processes. In addition to the local processes, oxygen-deficient water formed in the Angola Gyre is one of the source water masses of the poleward undercurrent, which feeds oxygen depleted water into the Benguela system. In order to simulate the oxygen distribution in the Benguela system, both physical transport as well as local biological processes need to be carefully adjusted in the model. The focus of the analysis is on the time scale and the relative contribution of the different oxygen related processes to the oxygen budgets in both the oxygen minimum zones. Although these are very different in both the OMZ, the model is found as suitable to produce oxygen minimum zones comparable with observations in the Benguela and the Angola Gyre as well. Variability of the oxygen concentration in the Angola Gyre depends strongly on organismic oxygen consumption, whereas the variability of the oxygen concentration on the Namibian shelf is governed mostly by

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

Interactions of aquaculture, marine coastal ecosystems, and near-shore waters: A bibliography. Bibliographies and literature of agriculture (Final)

International Nuclear Information System (INIS)

Hanfman, D.T.; Coleman, D.E.; Tibbitt, S.J.

1991-01-01

The bibliography contains selected literature citations on the interactions of aquaculture and marine coastal ecosystems. The focus is on aquaculture effluents and their impact on marine coastal ecosystems and waterways as well as the impact of pollutants on aquaculture development. Factors affecting these issues include domestic and industrial wastes, thermal discharges, acid rain, heavy metals, oil spills, and microbial contamination of marine waters and aquatic species. Coastal zone management, environmenal impact of aquaculture, and water quality issues are also included in the bibliography

Physical structure and algae community of summer upwelling off eastern Hainan

Science.gov (United States)

Xu, H.; Liu, S.; Xie, Q.; Hong, B.; Long, T.

2017-12-01

The upwelling system is the most productive ecosystem along the continental shelf of the northern South China Sea Shelf. It brings nutrient from bottom to surface and blooms biotic community driven by summer monsoon. In this study, we present observed results of physical and biotic community structures during August, 2015 in the upwelling system along Hainan eastern coast, which is one the strongest upwelling systems in the northern South China Sea. By using hydrological data collected by CTD, we found a significant cold water tongue with high salinity which extended from offshore to 100 m isobaths. However, dissolved oxygen (DO) showed a sandwich structure in which high core of DO concentration appeared at the layer from 5 m to 30 m. It possibly was caused by the advection transport of high DO from adjacent area. Basically, this upwelling system was constrained at northern area of 18.8ºN in horizontal due to the weakening summer monsoon in August. In addition, we collected water sample at the upwelling area and measured algae categories and concentration by high performance liquid chromatography (HPLC). Results show the biotic community was dominated by five types of algae mainly, they were diatoms, dinoflagellates, green algae, prokaryotes and prochlorococcus. And different patterns of different algae were demonstrated. In the upwelling area, diatoms and prokaryotes show opposite structures, and more complex pattern for the rest three algae indicating an active biotic community in the upwelling system.

Initial observation of upwelling along east coast of Peninsular Malaysia musica-gratis.softonic.it/ >musica gratis

Science.gov (United States)

Akhir, M.; Tanggang, F.

2013-12-01

There is no published evidence of upwelling in coastal area along the east coast of Peninsular Malaysia. However numbers of recent cruise data collected during the southwest monsoon found features of thermocline lifting and isolated cooler temperature water along the coast, These sign was observed along the 104°E from numbers of parallel transects. To confirm the presence of upwelling, satellite remote sensing data was used, and numerical model experiments were conducted. Cooler sea-surface temperature along the coast was observed from both in-situ and satellite data, while upward movement in the vertical profiles agreed with the location of upwelling from both in-situ and satellite data. Moreover, these data also show that the upwelled water band along the 104°E longitude stretch approximately 650 km long. Initially, southwesterly wind during this season is believed to be the important mechanism that contributed to this wind-induced Ekman upwelling. musica-gratis.softonic.it/ >musica gratis

Impact of river basin management on coastal water quality and ecosystem services: A southern Baltic estuary

Science.gov (United States)

Schernewski, Gerald; Hürdler, Jens; Neumann, Thomas; Stybel, Nardine; Venohr, Markus

2010-05-01

Eutrophication management is still a major challenge in the Baltic Sea region. Estuaries or coastal waters linked to large rivers cannot be managed independently. Nutrient loads into these coastal ecosystems depend on processes, utilisation, structure and management in the river basin. In practise this means that we need a large scale approach and integrated models and tools to analyse, assess and evaluate the effects of nutrient loads on coastal water quality as well as the efficiency of river basin management measures on surface waters and especially lagoons and estuaries. The Odra river basin, the Szczecin Lagoon and its coastal waters cover an area of about 150,000 km² and are an eutrophication hot-spot in the Baltic region. To be able to carry out large scale, spatially integrative analyses, we linked the river basin nutrient flux model MONERIS to the coastal 3D-hydrodynamic and ecosystem model ERGOM. Objectives were a) to analyse the eutrophication history in the river basin and the resulting functional changes in the coastal waters between early 1960's and today and b) to analyse the effects of an optimal nitrogen and phosphorus management scenario in the Oder/Odra river basin on coastal water quality. The models show that an optimal river basin management with reduced nutrient loads (e.g. N-load reduction of 35 %) would have positive effects on coastal water quality and algae biomass. The availability of nutrients, N/P ratios and processes like denitrification and nitrogen-fixation would show spatial and temporal changes. It would have positive consequences for ecosystems functions, like the nutrient retention capacity, as well. However, this optimal scenario is by far not sufficient to ensure a good coastal water quality according to the European Water Framework Directive. A "good" water quality in the river will not be sufficient to ensure a "good" water quality in the coastal waters. Further, nitrogen load reductions bear the risk of increased

Emergy analysis of coastal systems influenced by upwelling in northern Chile: Estimation of ecological-economic sustainability at multiple scales

Science.gov (United States)

Numerous studies carried out in a variety of environments have suggested that coastal marine systems generate a variety of goods and services for humanity. However, in recent decades there has been a marked degradation of these ecosystems, as well as over-exploitation of natural ...

Recreational impacts on the fauna of Australian coastal marine ecosystems.

Science.gov (United States)

Hardiman, Nigel; Burgin, Shelley

2010-11-01

This paper reviews recent research into the ecological impacts of recreation and tourism on coastal marine fauna in Australia. Despite the high and growing importance of water-based recreation to the Australian economy, and the known fragility of many Australian ecosystems, there has been relatively limited research into the effects of marine tourism and recreation, infrastructure and activities, on aquatic resources. In this paper we have reviewed the ecological impacts on fauna that are caused by outdoor recreation (including tourism) in Australian coastal marine ecosystems. We predict that the single most potentially severe impact of recreation may be the introduction and/or dispersal of non-indigenous species of marine organisms by recreational vessels. Such introductions, together with other impacts due to human activities have the potential to increasingly degrade recreation destinations. In response, governments have introduced a wide range of legislative tools (e.g., impact assessment, protected area reservation) to manage the recreational industry. It would appear, however, that these instruments are not always appropriately applied. Copyright 2010 Elsevier Ltd. All rights reserved.

A Lagrangian study tracing water parcel origins in the Canary Upwelling System

Directory of Open Access Journals (Sweden)

Evan Mason

2012-08-01

Full Text Available The regional ocean circulation within the Canary Upwelling System between 31°N and 35°N is studied using numerical tools. Seasonal mean and near-instantaneous velocity fields from a previously-generated climatological Regional Ocean Modelling System (ROMS solution of the Canary Basin are used to force a series of offline Lagrangian particle-tracking experiments. The primary objective is to identify the pathways through which water parcels arrive at the upwelling region north of Cape Ghir. Examining year-long pathways, the Azores Current contributes over 80% of particles annually, of which a large proportion arrive directly from offshore (from the northwest, while others travel along the shelf and slope from the Gulf of Cadiz. The remaining ~20% originate within the Gulf of Cadiz or come from the south, although the southern contribution is only significant in autumn and winter. When season-long pathways are considered, the alongshore contributions become increasingly important: northern contributions reach 40% in spring and summer, while southern values exceed 35% in winter. This study also shows that coastal upwelling changes both spatially and temporally. Upwelling becomes intensified near Cape Beddouza, with most upwelling occurring within ~40 km from shore although significant values may reach as far as 120 km offshore north of Cape Beddouza; at these locations the offshore integrated upwelling reaches as much as 4 times the offshore Ekman transport. In the Cape Beddouza area (32°N to 33°N, upwelling is negligible in February but intensifies in autumn, reaching as much as 3 times the offshore Ekman transport.

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.

A resilience framework for chronic exposures: water quality and ecosystem services in coastal social-ecological systems

Science.gov (United States)

We outline a tailored resilience framework that applies ecosystem service concepts to coastal social-ecological systems (SES) affected by water quality degradation. Unlike acute coastal disturbances such as hurricanes or oil spills, water quality issues, particularly those relate...

Bloom dynamics and life cycle strategies of two toxic dinoflagellates in a coastal upwelling system (NW Iberian Peninsula)

Science.gov (United States)

Bravo, Isabel; Fraga, Santiago; Isabel Figueroa, Rosa; Pazos, Yolanda; Massanet, Ana; Ramilo, Isabel

2010-02-01

A study of Gymnodinium catenatum and Alexandrium minutum blooms on the Galician coast was conducted from 2005 to 2007 in order to increase knowledge of the mechanisms governing recurrent blooms of these species. Considerable differences in their bloom dynamics were observed. G. catenatum blooms occurred in autumn and winter, following the pattern previously reported in the literature: they began off-shore and were advected to the Galician rias when a relaxation of the coastal upwelling occurred. On the other hand, A. minutum blooms developed inside embayments in spring and summer during the upwelling season and were associated with water stability and stratification. Both the vegetative population and the cyst distribution of A. minutum were related to less saline water from freshwater river outputs, which support a saline-gradient relationship postulated herein for this species. Dinoflagellates may produce both long-term double-walled cysts (resting) and short-term pellicle cysts. Resting cyst deposition and distribution in sediments showed that seeding occurred during the blooms of both species. However, the relationship between the cyst distribution in the sediments in Baiona Bay and the intensity and occurrence of G. catenatum blooms, suggests that the latter are not directly related to resting cyst germination. Moreover, the results presented in the present study point to other difference between the two species, such as the detection of pellicle cysts only for A. minutum. Finally, we discuss how the life cycle strategies of these two species may help to explain the different mechanisms of bloom formation reported herein.

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

Modelling shelf-ocean exchange and its biogeochemical consequences in coastal upwelling systems

DEFF Research Database (Denmark)

Muchamad, Al Azhar

margin bathymetry, and 3) what processes determine the observed variability of total organic carbon (TOC) content in shelf sediments underlying the upwelling system, with implications for the formation of petroleum source rocks. Here, a numerical ocean modeling approach is used in this thesis to explore...... processes and the development of anoxia/euxinia under the present day or past geological conditions. Thirdly and last, processes controlling distribution of total organic carbon (TOC) content in sediments across the continental margin is evaluated by application of the model to the Benguela upwelling system....... In the model, biological primary production and shelf bottom-water anoxia result in enhanced sedimentary TOC concentrations on the mid shelf and upper slope. The simulated TOCs implicate that bottom lateral transport only has a significant effect on increasing the deposition of the organic carbon on the mid...

Linking benthic biodiversity to the functioning of coastal ecosystems subjected to river runoff (NW Mediterranean

Directory of Open Access Journals (Sweden)

Harmelin–Vivien, M. L.

2009-12-01

Full Text Available Continental particulate organic matter (POM plays a major role in the functioning of coastal marine ecosystems as a disturbance as well as an input of nutrients. Relationships linking continental inputs from the Rhone River to biodiversity of the coastal benthic ecosystem and fishery production were investigated in the Golfe du Lion (NW Mediterranean Sea. Macrobenthic community diversity decreased when continen¬tal inputs of organic matter increased, whereas ecosystem production, measured by common sole (Solea solea fishery yields in the area, increased. Decreases in macrobenthic diversity were mainly related to an increasing abundance of species with specific functional traits, particularly deposit-feeding polychaetes. The decrease in macrobenthic diversity did not result in a decrease, but an increase in ecosystem production, as it enhanced the transfer of continental POM into marine food webs. The present study showed that it is necessary to consider functional traits of species, direct and indirect links between species, and feedback loops to understand the effects of biodiversity on ecosystem functioning and productivity.

Coastal Zone Ecosystem Services: from science to values and decision making; a case study.

Science.gov (United States)

Luisetti, T; Turner, R K; Jickells, T; Andrews, J; Elliott, M; Schaafsma, M; Beaumont, N; Malcolm, S; Burdon, D; Adams, C; Watts, W

2014-09-15

This research is concerned with the following environmental research questions: socio-ecological system complexity, especially when valuing ecosystem services; ecosystems stock and services flow sustainability and valuation; the incorporation of scale issues when valuing ecosystem services; and the integration of knowledge from diverse disciplines for governance and decision making. In this case study, we focused on ecosystem services that can be jointly supplied but independently valued in economic terms: healthy climate (via carbon sequestration and storage), food (via fisheries production in nursery grounds), and nature recreation (nature watching and enjoyment). We also explored the issue of ecosystem stock and services flow, and we provide recommendations on how to value stock and flows of ecosystem services via accounting and economic values respectively. We considered broadly comparable estuarine systems located on the English North Sea coast: the Blackwater estuary and the Humber estuary. In the past, these two estuaries have undergone major land-claim. Managed realignment is a policy through which previously claimed intertidal habitats are recreated allowing the enhancement of the ecosystem services provided by saltmarshes. In this context, we investigated ecosystem service values, through biophysical estimates and welfare value estimates. Using an optimistic (extended conservation of coastal ecosystems) and a pessimistic (loss of coastal ecosystems because of, for example, European policy reversal) scenario, we find that context dependency, and hence value transfer possibilities, vary among ecosystem services and benefits. As a result, careful consideration in the use and application of value transfer, both in biophysical estimates and welfare value estimates, is advocated to supply reliable information for policy making. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

Top-down control as important as nutrient enrichment for eutrophication effects in North Atlantic coastal ecosystems

NARCIS (Netherlands)

Ostman, Orjan; Eklof, Johan; Eriksson, Britas Klemens; Olsson, Jens; Moksnes, Per-Olav; Bergstrom, Ulf

Seagrass and seaweed habitats constitute hotspots for diversity and ecosystem services in coastal ecosystems. These habitats are subject to anthropogenic pressures, of which eutrophication is one major stressor. Eutrophication favours fast-growing ephemeral algae over perennial macroalgae and

Strategies of bioremediation of a contaminated coastal Ecosystem (Bolmon Lagoon, South-Easter Mediterranean Coast)

International Nuclear Information System (INIS)

Charpy-Roubaud, C.; Fayolle, S.; Franquet, E.; Pietri, L.; Anselmet, F.; Brun, L.; Roux, B.

2009-01-01

Bolmon ecosystem (Bouches du Rhone, South-easter France) is a coastal mediterranean lagoon. This ecosystem presents a great interest in terms of ecology, economy and cultural aspects. Bolmon is connected to the salty Berre pond, itself connected to Mediterranean sea, via tiny artificial channels and a main one (rove channel) that also bounds it to the South. (Author)

Strategies of bioremediation of a contaminated coastal Ecosystem (Bolmon Lagoon, South-Easter Mediterranean Coast)

Energy Technology Data Exchange (ETDEWEB)

Charpy-Roubaud, C.; Fayolle, S.; Franquet, E.; Pietri, L.; Anselmet, F.; Brun, L.; Roux, B.

2009-07-01

Bolmon ecosystem (Bouches du Rhone, South-easter France) is a coastal mediterranean lagoon. This ecosystem presents a great interest in terms of ecology, economy and cultural aspects. Bomon is connected to the salty Berre pond, itself connected to Mediterranean sea, via tiny artificial channels and a main one (rove channel) that also bounds it to the South. (Author)

Integrating societal perspectives and values for improved stewardship of a coastal ecosystem engineer

Directory of Open Access Journals (Sweden)

Steven B. Scyphers

2014-09-01

Full Text Available Oyster reefs provide coastal societies with a vast array of ecosystem services, but are also destructively harvested as an economically and culturally important fishery resource, exemplifying a complex social-ecological system (SES. Historically, societal demand for oysters has led to destructive and unsustainable levels of harvest, which coupled with multiple other stressors has placed oyster reefs among the most globally imperiled coastal habitats. However, more recent studies have demonstrated that large-scale restoration is possible and that healthy oyster populations can be sustained with effective governance and stewardship. However, both of these require significant societal support or financial investment. In our study, we explored relationships among how coastal societies (1 perceive and value oyster ecosystem services, (2 recognize and define problems associated with oyster decline, and (3 perceive or support stewardship initiatives. We specifically focused on the SES of eastern oysters (Crassostrea virginica and coastal societies in the northern Gulf of Mexico, a region identified as offering among the last and best opportunities to sustainably balance conservation objectives with a wild fishery. We found that, in addition to harvest-related benefits, oysters were highly valued for providing habitat, mitigating shoreline erosion, and improving water quality or clarity. Our results also showed that although most respondents recognized that oyster populations have declined, many respondents characterized the problem differently than most scientific literature does. Among a variety of initiatives for enhancing sustainability, spawning sanctuaries and reef restoration were well supported in all states, but support for harvest reductions was less consistent. Our study suggests that public support for maintaining both harvest and ecosystem services exists at societal levels and that enhancing public awareness regarding the extent and causes

Impact of petroleum pollution on aquatic coastal ecosystems in Brazil

International Nuclear Information System (INIS)

Silva, E.M. da; Peso-Aguiar, M.C.; Navarro, M.F.T.; Chastinet, C.B.A.

1997-01-01

Although oil activities generate numerous forms of environmental impact on biological communities, studies of these impacts on Brazilian coastal ecosystems are rate. Results of tests for the content of oil in sediments and organisms indicate a substantially high rate of degradation. Results for uptake of polycyclic aromatic hydrocarbons in bivalves suggested the recent occurrence of oil spills and that these organisms differed in their capabilities to bioconcentrate oil. The mangrove community has suffered constant inputs of oil and has responded with increased numbers of aerial roots, generation of malformed leaves and fruits by plants, and a decrease in litter production. Studies of the impact of oil on rocky shore communities and the toxicity of oil and its by-products to marine organisms have confirmed the results reported in the literature. Presently most of the available studies deal with the macroscopic effects of oil on organisms and have indicated that the nature of oil, climate characteristics, the physical environment, and the structure of the community influence the symptoms of oil contamination in organisms of coastal waters. Long-term studies should be carried out to assess changes in community structure, sublethal effects in populations, and the resilience of contaminated ecosystems

A statistical approach to coastal upwelling in the Baltic Sea based on the analysis of satellite data for 1990-2009

Directory of Open Access Journals (Sweden)

Andreas Lehmann

2012-06-01

Full Text Available A statistical analysis of Baltic Sea upwelling has been carried out to cover, for the first time, the entire sea area for the period 1990-2009. Weekly composite SST maps based on NOAA/AVHRR satellite data were used to evaluate the location and frequency of upwelling. The results obtained were analysed and compared with earlier studies with excellent agreement. Our study enables the most intense upwelling areas in the entire Baltic Sea to be evaluated. According to the analysis of 443 SST maps, the most common upwelling regions are found off the Swedish south and east coasts (frequency 10-25%, the Swedish coast of the Bothnian Bay (16%, the southern tip of Gotland (up to 15%, and the Finnish coast of the Gulf of Finland (up to 15%. Pronounced upwelling also occurs off the Estonian coast and the Baltic east coast (up to 15%, the Polish coast and the west coast of Rügen (10-15%; otherwise the upwelling frequency was between 5 and 10%. Additionally, simulated SST distributions derived from a Baltic Sea numerical model were analysed for the same period. Furthermore, at specific positions close to the coastline, surface winds based on the SMHI meteorological data base were analysed for the same 20-year period. Wind components parallel to the coast were discriminated into favourable and unfavourable winds forcing upwelling. The obtained frequencies of upwelling-favourable winds fit very well the observed upwelling frequencies derived from satellite SST maps. A positive trend of upwelling frequencies along the Swedish east coast and the Finnish coast of the Gulf of Finland was calculated for the period 1990-2009.

Quantifying Economic Value of Coastal Ecosystem Services: A Review

Directory of Open Access Journals (Sweden)

Seyedabdolhossein Mehvar

2018-01-01

Full Text Available The complexity of quantifying ecosystem services in monetary terms has long been a challenging issue for economists and ecologists. Many case specific valuation studies have been carried out in various parts of the World. Yet, a coherent review on the valuation of coastal ecosystem services (CES, which systematically describes fundamental concepts, analyzes reported applications, and addresses the issue of climate change (CC impacts on the monetary value of CES is still lacking. Here, we take a step towards addressing this knowledge gap by pursuing a coherent review that aims to provide policy makers and researchers in multidisciplinary teams with a summary of the state-of-the-art and a guideline on the process of economic valuation of CES and potential changes in these values due to CC impacts. The article highlights the main concepts of CES valuation studies and offers a systematic analysis of the best practices by analyzing two global scale and 30 selected local and regional case studies, in which different CES have been valued. Our analysis shows that coral reefs and mangroves are among the most frequently valued ecosystems, while sea-grass beds are the least considered ones. Currently, tourism and recreation services as well as storm protection are two of the most considered services representing higher estimated value than other CES. In terms of the valuation techniques used, avoided damage, replacement and substitute cost method as well as stated preference method are among the most commonly used valuation techniques. Following the above analysis, we propose a methodological framework that provides step-wise guidance and better insight into the linkages between climate change impacts and the monetary value of CES. This highlights two main types of CC impacts on CES: one being the climate regulation services of coastal ecosystems, and the other being the monetary value of services, which is subject to substantial uncertainty. Finally, a

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.

Exploratory analysis of atmospheric pollution in a coastal forest ecosystem in central Italy

Directory of Open Access Journals (Sweden)

Rita Aromolo

2015-02-01

Full Text Available Exploratory analysis of atmospheric pollution in a coastal forest ecosystem in central Italy - The study of spatial and temporal distribution of heavy metals in the atmosphere through the continuous assessment of deposition is of great interest for the analysis of anthropogenic pressure on the environment and the potential toxicity to humans and other living organisms. Information based on reliable estimates of heavy metals is therefore crucial for the evaluation of environmental quality. Trends in heavy metal concentration in atmospheric depositions on a coastal forest ecosystem (Castelporziano, Rome are analyzed in the present study based on a three-year monitoring field survey over three sites representative of different woodland characteristics in the area. Our results highlight both the influence of transportation processes in the short and medium distance based on the human pressure reflecting urban expansion and infrastructure development on the fringe of Castelporziano pristine forest. Further studies investigating the latent correlation with meteorological variables at various temporal scales are needed to provide a comprehensive picture of environmental conditions in a forest ecosystem subjected to increasing human pressure. Analysis of runoff water quality and the determination of other heavy metals, such as arsenic, may identify additional sources of pollution impacting soil and forest ecosystem.

An invasive foundation species enhances multifunctionality in a coastal ecosystem.

Science.gov (United States)

Ramus, Aaron P; Silliman, Brian R; Thomsen, Mads S; Long, Zachary T

2017-08-08

While invasive species often threaten biodiversity and human well-being, their potential to enhance functioning by offsetting the loss of native habitat has rarely been considered. We manipulated the abundance of the nonnative, habitat-forming seaweed Gracilaria vermiculophylla in large plots (25 m 2 ) on southeastern US intertidal landscapes to assess impacts on multiple ecosystem functions underlying coastal ecosystem services. We document that in the absence of native habitat formers, this invasion has an overall positive, density-dependent impact across a diverse set of ecosystem processes (e.g., abundance and richness of nursery taxa, flow attenuation). Manipulation of invader abundance revealed both thresholds and saturations in the provisioning of ecosystem functions. Taken together, these findings call into question the focus of traditional invasion research and management that assumes negative effects of nonnatives, and emphasize the need to consider context-dependence and integrative measurements when assessing the impact of an invader, including density dependence, multifunctionality, and the status of native habitat formers. This work supports discussion of the idea that where native foundation species have been lost, invasive habitat formers may be considered as sources of valuable ecosystem functions.

Characterizing Coastal Ecosystem Service Trade-offs with Future Urban Development in a Tropical City.

Science.gov (United States)

Richards, Daniel R; Friess, Daniel A

2017-11-01

With rapid urbanization in the coastal zone and increasing habitat losses, it is imperative to understand how urban development affects coastal biodiversity and ecosystem service provision. Furthermore, it is important to understand how habitat fragments can best be incorporated into broader land use planning and coastal management, in order to maximize the environmental benefits they provide. In this study, we characterized the trade-offs between (a) urban development and individual mangrove environmental indicators (habitat quality and ecosystem services), and (b) between different environmental indicators in the tropical nation of Singapore. A range of biological, biophysical, and cultural indicators, including carbon, charcoal production, support for offshore fisheries, recreation, and habitat quality for a threatened species were quantified using field-based, remote sensing, and expert survey methods. The shape of the trade-off Pareto frontiers was analyzed to assess the sensitivity of environmental indicators for development. When traded off individually with urban development, four out of five environmental indicators were insensitive to development, meaning that relatively minor degradation of the indicator occurred while development was below a certain threshold, although indicator loss accelerated once this threshold was reached. Most of the pairwise relationships between the five environmental indicators were synergistic; only carbon storage and charcoal production, and charcoal production and recreational accessibility showed trade-offs. Trade-off analysis and land use optimization using Pareto frontiers could be a useful decision-support tool for understanding how changes in land use and coastal management will impact the ability of ecosystems to provide environmental benefits.

Characterizing Coastal Ecosystem Service Trade-offs with Future Urban Development in a Tropical City

Science.gov (United States)

Richards, Daniel R.; Friess, Daniel A.

2017-11-01

With rapid urbanization in the coastal zone and increasing habitat losses, it is imperative to understand how urban development affects coastal biodiversity and ecosystem service provision. Furthermore, it is important to understand how habitat fragments can best be incorporated into broader land use planning and coastal management, in order to maximize the environmental benefits they provide. In this study, we characterized the trade-offs between (a) urban development and individual mangrove environmental indicators (habitat quality and ecosystem services), and (b) between different environmental indicators in the tropical nation of Singapore. A range of biological, biophysical, and cultural indicators, including carbon, charcoal production, support for offshore fisheries, recreation, and habitat quality for a threatened species were quantified using field-based, remote sensing, and expert survey methods. The shape of the trade-off Pareto frontiers was analyzed to assess the sensitivity of environmental indicators for development. When traded off individually with urban development, four out of five environmental indicators were insensitive to development, meaning that relatively minor degradation of the indicator occurred while development was below a certain threshold, although indicator loss accelerated once this threshold was reached. Most of the pairwise relationships between the five environmental indicators were synergistic; only carbon storage and charcoal production, and charcoal production and recreational accessibility showed trade-offs. Trade-off analysis and land use optimization using Pareto frontiers could be a useful decision-support tool for understanding how changes in land use and coastal management will impact the ability of ecosystems to provide environmental benefits.

El Niño and similar perturbation effects on the benthos of the Humboldt, California, and Benguela Current upwelling ecosystems

Science.gov (United States)

Arntz, W. E.; Gallardo, V. A.; Gutiérrez, D.; Isla, E.; Levin, L. A.; Mendo, J.; Neira, C.; Rowe, G. T.; Tarazona, J.; Wolff, M.

2006-03-01

To a certain degree, Eastern Boundary Current (EBC) ecosystems are similar: Cold bottom water from moderate depths, rich in nutrients, is transported to the euphotic zone by a combination of trade winds, Coriolis force and Ekman transport. The resultant high primary production fuels a rich secondary production in the upper pelagic and nearshore zones, but where O2 exchange is restricted, it creates oxygen minimum zones (OMZs) at shelf and upper slope (Humboldt and Benguela Current) or slope depths (California Current). These hypoxic zones host a specifically adapted, small macro- and meiofauna together with giant sulphur bacteria that use nitrate to oxydise H2S. In all EBC, small polychaetes, large nematodes and other opportunistic benthic species have adapted to the hypoxic conditions and co-exist with sulphur bacteria, which seem to be particularly dominant off Peru and Chile. However, a massive reduction of macrobenthos occurs in the core of the OMZ. In the Humboldt Current area the OMZ ranges between immigrants. The autochthonous benthic fauna emigrates to deeper water or poleward, or suffers mortality. However, some local macrofaunal species experience important population proliferations, presumably due to improved oxygenation (in the southern hemisphere), higher temperature tolerance, reduced competition or the capability to use different food. Both these negative and positive effects of El Niño influence local artisanal fisheries and the livelihood of coastal populations. In the Humboldt Current system the hypoxic seafloor at outer shelf depths receives important flushing from the equatorial zone, causing havoc on the sulphur bacteria mats and immediate recolonisation of the sediments by mega- and macrofauna. Conversely, off California, the intruding equatorial water masses appear to have lower oxygen than ambient waters, and may cause oxygen deficiency at upper slope depths. Effects of this change have not been studied in detail, although shrimp and other

On an upwelling front along the west coast of India during later part of southwest monsoon

Digital Repository Service at National Institute of Oceanography (India)

Unnikrishnan, A.S.; Antony, M.K.

A coastal front, associated with upwelling, is identified from the observed thermal field along the west coast of India during September, 1987. The front, which is seen very clearly upto a depth of about 75 m, has a horizontal gradient...

Influence of upwelling induced near shore hypoxia on the Alappuzha mud banks, South West Coast of India

Digital Repository Service at National Institute of Oceanography (India)

GireeshKumar, T.R.; Mathew, D.; Pratihary, A.K.; Naik, H.; Narvekar, K.U.; Araujo, J.; Balachandran, K.K.; Muraleedharan, K.R.; Thorat, B.R.; Nair, M.; Naqvi, S.W.A.

The results of the first time-series measurements spanning 18-weeks (22 April to 20 September 2014) from a coastal environment (Alappuzha, southwest India), where two process of upwelling and mud banks are concurrent during summer monsoon...

Coastal upwelling by wind-driven forcing in Jervis Bay, New South Wales: A numerical study for 2011

Science.gov (United States)

Sun, Youn-Jong; Jalón-Rojas, Isabel; Wang, Xiao Hua; Jiang, Donghui

2018-06-01

The Princeton Ocean Model (POM) was used to investigate an upwelling event in Jervis Bay, New South Wales (SE Australia), with varying wind directions and strengths. The POM was adopted with a downscaling approach for the regional ocean model one-way nested to a global ocean model. The upwelling event was detected from the observed wind data and satellite sea surface temperature images. The validated model reproduced the upwelling event showing the input of bottom cold water driven by wind to the bay, its subsequent deflection to the south, and its outcropping to the surface along the west and south coasts. Nevertheless, the behavior of the bottom water that intruded into the bay varied with different wind directions and strengths. Upwelling-favorable wind directions for flushing efficiency within the bay were ranked in the following order: N (0°; northerly) > NNE (30°; northeasterly) > NW (315°; northwesterly) > NE (45°; northeasterly) > ENE (60°; northeasterly). Increasing wind strengths also enhance cold water penetration and water exchange. It was determined that wind-driven downwelling within the bay, which occurred with NNE, NE and ENE winds, played a key role in blocking the intrusion of the cold water upwelled through the bay entrance. A northerly wind stress higher than 0.3 N m-2 was required for the cold water to reach the northern innermost bay.

Winter-summer nutrient composition linkage to algae-produced toxins in shellfish at a eutrophic coastal lagoon (Óbidos lagoon, Portugal)

Science.gov (United States)

Pereira, Patrícia; Botelho, Maria João; Cabrita, Maria Teresa; Vale, Carlos; Moita, Maria Teresa; Gonçalves, Célia

2012-10-01

The current work examines the linkage of pronounced winter-summer fluctuations on the nutrient composition with phytoplankton assemblages and mussel toxicity produced by the presence of toxic dinoflagellates. The work was performed at the Óbidos lagoon, a coastal eutrophic ecosystem that is permanently connected to an area characterized by frequent upwelling episodes. The lagoon and adjoining coastal area exhibit recurrent incidents of diarrhetic and paralytic shellfish poisoning. The conclusions are based on: (1) inorganic and organic nutrients at five sites of the lower, middle and upper Óbidos lagoon, and inorganic nutrients at two sites of the adjacent coastal area; biannual campaigns were performed in winter and summer between 2006 and 2010; (2) phytoplankton assemblages at three sites of the lagoon (located at lower and upper areas) in winter and summer of 2009; (3) algae-derived toxicity of wild mussels from the lower lagoon and coastal area, on a 1-2 week time scale, over 2006 and 2009. Nutrient molar ratios in Óbidos lagoon contrast between winter and summer. The lower median ratios DIN:P (31 and 0.8) and Si:P (11 and 3.3) in summer reflect the excess of phosphate. Excess was mainly attributed to phosphorus regeneration in sediments of the upper lagoon with accentuated symptoms of eutrophication. Dissolved organic nitrogen and dissolved organic phosphorus were also higher in summer, particularly in this area. No significant winter-summer differences were recorded for nutrient ratios in the adjacent coastal area. Phytoplankton assemblages pointed to a winter-summer contrast characterized by a shift of non-siliceous-based phytoplankton to diatoms. The toxic dinoflagellate species (Gymnodinium catenatum, Dinophysis cf. acuminata and Dinophysis acuta), presumably imported from the adjacent coast following upwelling episodes in summer, were observed in the lower lagoon. In summer of the two surveyed years, toxins produced by dinoflagellates occurred in

A numerical investigation of the atmosphere-ocean thermal contrast over the coastal upwelling region of Cabo Frio, Brazil

Energy Technology Data Exchange (ETDEWEB)

Dourado, M. [Departamento de Meteorologia, Universidade Federal de Pelotas, Pelotas RS (Brazil)]. E-mail: marcelo_dourado@ufpel.edu.br; Pereira de Oliveira, A. [Departamento de Ciencias Atmosfericas, Instituto de Astronomia, Geofisica e Ciencias Atmosfericas, Universidade de Sao Paulo, (Brazil)

2008-01-15

An one-dimensional atmospheric second order closure model, coupled to an oceanic mixed layer model, is used to investigate the short term variation of the atmospheric and oceanic boundary layers in the coastal upwelling area of Cabo Frio, Brazil (23 degrees Celsius S, 42 degrees Celsius 08' W). The numerical simulations were carried out to evaluate the impact caused by the thermal contrast between atmosphere and ocean on the vertical extent and other properties of both atmospheric and oceanic boundary layers. The numerical simulations were designed taking as reference the observations carried out during the passage of a cold front that disrupted the upwelling regime in Cabo Frio in July of 1992. The simulations indicated that in 10 hours the mechanical mixing, sustained by a constant background flow of 10 m s-1, increases the atmospheric boundary layer in 214 m when the atmosphere is initially 2 K warmer than the ocean (positive thermal contrast observed during upwelling regime). For an atmosphere initially -2 K colder than the ocean (negative thermal contrast observed during passage of the cold front), the incipient thermal convection intensifies the mechanical mixing increasing the vertical extent of the atmospheric boundary layer in 360 m. The vertical evolution of the atmospheric boundary layer is consistent with the observations carried out in Cabo Frio during upwelling condition. When the upwelling is disrupted, the discrepancy between the simulated and observed atmospheric boundary layer heights in Cabo Frio during July of 1992 increases considerably. During the period of 10 hours, the simulated oceanic mixed layer deepens 2 m and 5.4 m for positive and negative thermal contrasts of 2 K and -2 K, respectively. In the latter case, the larger vertical extent of the oceanic mixed layer is due to the presence of thermal convection in the atmospheric boundary layer, which in turn is associated to the absence of upwelling caused by the passage of cold fronts

Cloud shading and fog drip influence the metabolism of a coastal pine ecosystem.

Science.gov (United States)

Carbone, Mariah S; Park Williams, A; Ambrose, Anthony R; Boot, Claudia M; Bradley, Eliza S; Dawson, Todd E; Schaeffer, Sean M; Schimel, Joshua P; Still, Christopher J

2013-02-01

Assessing the ecological importance of clouds has substantial implications for our basic understanding of ecosystems and for predicting how they will respond to a changing climate. This study was conducted in a coastal Bishop pine forest ecosystem that experiences regular cycles of stratus cloud cover and inundation in summer. Our objective was to understand how these clouds impact ecosystem metabolism by contrasting two sites along a gradient of summer stratus cover. The site that was under cloud cover ~15% more of the summer daytime hours had lower air temperatures and evaporation rates, higher soil moisture content, and received more frequent fog drip inputs than the site with less cloud cover. These cloud-driven differences in environmental conditions translated into large differences in plant and microbial activity. Pine trees at the site with greater cloud cover exhibited less water stress in summer, larger basal area growth, and greater rates of sap velocity. The difference in basal area growth between the two sites was largely due to summer growth. Microbial metabolism was highly responsive to fog drip, illustrated by an observed ~3-fold increase in microbial biomass C with increasing summer fog drip. In addition, the site with more cloud cover had greater total soil respiration and a larger fractional contribution from heterotrophic sources. We conclude that clouds are important to the ecological functioning of these coastal forests, providing summer shading and cooling that relieve pine and microbial drought stress as well as regular moisture inputs that elevate plant and microbial metabolism. These findings are important for understanding how these and other seasonally dry coastal ecosystems will respond to predicted changes in stratus cover, rainfall, and temperature. © 2012 Blackwell Publishing Ltd.

Seasonal and inter-annual variation of mesozooplankton in the coastal upwelling zone off central-southern Chile

Science.gov (United States)

Escribano, Ruben; Hidalgo, Pamela; González, Humberto; Giesecke, Ricardo; Riquelme-Bugueño, Ramiro; Manríquez, Karen

2007-11-01

Zooplankton sampling at Station 18 off Concepción (36°30‧S and 73°07‧W), on an average frequency of 30 days (August 2002 to December 2005), allowed the assessment of seasonal and inter-annual variation in zooplankton biomass, its C and N content, and the community structure in relation to upwelling variability. Copepods contributed 79% of the total zooplankton community and were mostly represented by Paracalanus parvus, Oithona similis, Oithona nana, Calanus chilensis, and Rhincalanus nasutus. Other copepod species, euphausiids (mainly Euphausia mucronata), gelatinous zooplankton, and crustacean larvae comprised the rest of the community. Changes in the depth of the upper boundary of the oxygen minimum zone indicated the strongly seasonal upwelling pattern. The bulk of zooplankton biomass and total copepod abundance were both strongly and positively associated with a shallow (oxygen minimum zone; these values increased in spring/summer, when upwelling prevailed. Gelatinous zooplankton showed positive abundance anomalies in the spring and winter, whereas euphausiids had no seasonal pattern and a positive anomaly in the fall. The C content and the C/N ratio of zooplankton biomass significantly increased during the spring when chlorophyll- a was high (>5 mg m -3). No major changes in zooplankton biomass and species were found from one year to the next. We concluded that upwelling is the key process modulating variability in zooplankton biomass and its community structure in this zone. The spring/summer increase in zooplankton may be largely the result of the aggregation of dominant copepods within the upwelling region; these may reproduce throughout the year, increasing their C content and C/N ratios given high diatom concentrations.

Including ecosystem dynamics in risk assessment of radioactive waste in coastal regions

International Nuclear Information System (INIS)

Kumblad, L.; Kautsky, U.; Gilek, M.

2000-01-01

Radiation protection has mainly focused on assessing and minimising risks of negative effects on human health. Although some efforts have been made to estimate effects on non-human populations, modelling of radiation risks to other components of the ecosystem have often lead to more or less disappointing results. In this paper an ecosystem approach is suggested and exemplified with a preliminary 14 C model of a coastal Baltic ecosystem. Advantages with the proposed ecosystem approach are for example the possibility to detect important but previously neglected pathways to humans since the whole ecosystem is analysed. The results from the model indicate that a rather small share of hypothetical released 14 C would accumulate in biota due to large water exchange in the modelled area. However, modelled future scenarios imply opposite results, i.e. relatively high doses in biota, due to changes of the physical properties in the area that makes a larger accumulation possible. (author)

Millennium Ecosystem Assessment: MA Ecosystems

Data.gov (United States)

National Aeronautics and Space Administration — The Millennium Ecosystem Assessment: MA Ecosystems provides data and information on the extent and classification of ecosystems circa 2000, including coastal,...

Fate and effects of petroleum hydrocarbons in marine coastal ecosystems

International Nuclear Information System (INIS)

Vanderhorst, J.R.

1977-01-01

Preliminary results are reported from field and laboratory studies on the effects of petroleum hydrocarbons on marine organisms of Northwest Pacific coastal ecosystems. Chemical methods for the characterization of test solutions for specific hydrocarbons (benzene, toluene, xylene, and heptodecane) were developed concurrently with population and community studies of the effects of short-term and chronic exposures. Results are reported from studies on algae (Ulva), clams (protothaca staminea), crustaceans (Anomyx and Neomysis) and burrowing worms

FAUNA OF COLEPTERA,TENEBRIORIDAE OF ARID COASTAL AND ISLAND ECOSYSTEMS OF THE CASPIAN SEA.

Directory of Open Access Journals (Sweden)

G. M. Abdurakhmanov

2014-01-01

Full Text Available Aim. The aim of the given paper is to expose species structure and geographical distribution of Coleoptera, Tenebrioridae (C, T of coastal and island ecosystem of the Caspian Sea. The given report is compiled of the matcrials, collected in different periods by authors (1961-2013 in the Caucasian part of the Caspian Sea, in the south of the European part of the Russian Federation, Kazakhstan, islands (the Chechen island, the Nord island. The Tuleniyisland. The Kulaly island, collective materials (ZIN; RAS, museum of Zoology of MSU, Institute NAN of Azerbaijan, National museum of Georgia and materials published (Kryzhanovsky, 1965, Medvedev, 1987, 1990; Medvedev, Nepesova, 1990; Shuster, 1934; Kaluzhnaya, 1982; Arzanov and others, 2004, Egorov, 2006.Methods. We used the traditional methods of collecting (hand picking, traps soil, soil traps light amplification light traps, processing and material definition. List of species composition discussed fauna composed by modern taxonomy using directories. Location. Coastal and island ecosystems of the Caspian sea.Results. Species structure and data on general and regional distribution of C,T of coastal and island ecosystems of the Caspian Sea is represented in the paper. Faund discussed is widely represented in the fauna of arid regions of land, especially in the fauna of subtropical deserts and semideserts.Main conclusions. Results of the study will be a step in the determination of age of the islands through the biological diversity and the consequent level regime of the Caspian Sea, as well as possible changes in the population structure of darkling beetles (Coleoptera: Tenebrionidae on island ecosystems.

Comparing marine and terrestrial ecosystems: Implications for the design of coastal marine reserves

Science.gov (United States)

Carr, M.H.; Neigel, J.E.; Estes, J.A.; Andelman, S.; Warner, R.R.; Largier, J. L.

2003-01-01

Concepts and theory for the design and application of terrestrial reserves is based on our understanding of environmental, ecological, and evolutionary processes responsible for biological diversity and sustainability of terrestrial ecosystems and how humans have influenced these processes. How well this terrestrial-based theory can be applied toward the design and application of reserves in the coastal marine environment depends, in part, on the degree of similarity between these systems. Several marked differences in ecological and evolutionary processes exist between marine and terrestrial ecosystems as ramifications of fundamental differences in their physical environments (i.e., the relative prevalence of air and water) and contemporary patterns of human impacts. Most notably, the great extent and rate of dispersal of nutrients, materials, holoplanktonic organisms, and reproductive propagules of benthic organisms expand scales of connectivity among near-shore communities and ecosystems. Consequently, the "openness" of marine populations, communities, and ecosystems probably has marked influences on their spatial, genetic, and trophic structures and dynamics in ways experienced by only some terrestrial species. Such differences appear to be particularly significant for the kinds of organisms most exploited and targeted for protection in coastal marine ecosystems (fishes and macroinvertebrates). These and other differences imply some unique design criteria and application of reserves in the marine environment. In explaining the implications of these differences for marine reserve design and application, we identify many of the environmental and ecological processes and design criteria necessary for consideration in the development of the analytical approaches developed elsewhere in this Special Issue.

Atmospheric Wind Relaxations and the Oceanic Response in the California Current Large Marine Ecosystem

Science.gov (United States)

Fewings, M. R.; Dorman, C. E.; Washburn, L.; Liu, W.

2010-12-01

On the West Coast of North America in summer, episodic relaxation of the upwelling-favorable winds causes warm water to propagate northward from southern to central California, against the prevailing currents [Harms and Winant 1998, Winant et al. 2003, Melton et al. 2009]. Similar wind relaxations are an important characteristic of coastal upwelling ecosystems worldwide. Although these wind relaxations have an important influence on coastal ocean dynamics, no description exists of the regional atmospheric patterns that lead to wind relaxations in southern California, or of the regional ocean response. We use QuikSCAT wind stress, North American Regional Reanalysis atmospheric pressure products, water temperature and velocity from coastal ocean moorings, surface ocean currents from high-frequency radars, and MODIS satellite sea-surface temperature and ocean color images to analyze wind relaxation events and the ocean response. We identify the events based on an empirical index calculated from NDBC buoy winds [Melton et al. 2009]. We describe the regional evolution of the atmosphere from the Gulf of Alaska to Baja California over the few days leading up to wind relaxations, and the coastal ocean temperature, color, and current response off southern and central California. We analyze ~100 wind relaxation events in June-September during the QuikSCAT mission, 1999-2009. Our results indicate south-central California wind relaxations in summer are tied to mid-level atmospheric low-pressure systems that form in the Gulf of Alaska and propagate southeastward over 3-5 days. As the low-pressure systems reach southern California, the atmospheric pressure gradient along the coast weakens, causing the surface wind stress to relax to near zero. The weak wind signal appears first at San Diego and propagates northward. QuikSCAT data indicate the relaxed winds extend over the entire Southern California Bight and up to 200 km offshore of central California. Atmospheric dynamics in

Catchment2Coast: A systems approach to coupled river-coastal ecosystem science and management

CSIR Research Space (South Africa)

Monteiro, PMS

2009-07-01

Full Text Available Catchment2Coast was an interdisciplinary research and modelling project that aimed to improve understanding of the linkages between coastal ecosystems and the adjacent river catchments. The project involved nine partner organizations from three...

Development of a 3D coupled physical-biogeochemical model for the Marseille coastal area (NW Mediterranean Sea): what complexity is required in the coastal zone?

Science.gov (United States)

Fraysse, Marion; Pinazo, Christel; Faure, Vincent Martin; Fuchs, Rosalie; Lazzari, Paolo; Raimbault, Patrick; Pairaud, Ivane

2013-01-01

Terrestrial inputs (natural and anthropogenic) from rivers, the atmosphere and physical processes strongly impact the functioning of coastal pelagic ecosystems. The objective of this study was to develop a tool for the examination of these impacts on the Marseille coastal area, which experiences inputs from the Rhone River and high rates of atmospheric deposition. Therefore, a new 3D coupled physical/biogeochemical model was developed. Two versions of the biogeochemical model were tested, one model considering only the carbon (C) and nitrogen (N) cycles and a second model that also considers the phosphorus (P) cycle. Realistic simulations were performed for a period of 5 years (2007-2011). The model accuracy assessment showed that both versions of the model were able of capturing the seasonal changes and spatial characteristics of the ecosystem. The model also reproduced upwelling events and the intrusion of Rhone River water into the Bay of Marseille well. Those processes appeared to greatly impact this coastal oligotrophic area because they induced strong increases in chlorophyll-a concentrations in the surface layer. The model with the C, N and P cycles better reproduced the chlorophyll-a concentrations at the surface than did the model without the P cycle, especially for the Rhone River water. Nevertheless, the chlorophyll-a concentrations at depth were better represented by the model without the P cycle. Therefore, the complexity of the biogeochemical model introduced errors into the model results, but it also improved model results during specific events. Finally, this study suggested that in coastal oligotrophic areas, improvements in the description and quantification of the hydrodynamics and the terrestrial inputs should be preferred over increasing the complexity of the biogeochemical model.

Coastal livelihood transitions under globalization with implications for trans-ecosystem interactions.

Science.gov (United States)

Kramer, Daniel B; Stevens, Kara; Williams, Nicholas E; Sistla, Seeta A; Roddy, Adam B; Urquhart, Gerald R

2017-01-01

Anthropogenic threats to natural systems can be exacerbated due to connectivity between marine, freshwater, and terrestrial ecosystems, complicating the already daunting task of governance across the land-sea interface. Globalization, including new access to markets, can change social-ecological, land-sea linkages via livelihood responses and adaptations by local people. As a first step in understanding these trans-ecosystem effects, we examined exit and entry decisions of artisanal fishers and smallholder farmers on the rapidly globalizing Caribbean coast of Nicaragua. We found that exit and entry decisions demonstrated clear temporal and spatial patterns and that these decisions differed by livelihood. In addition to household characteristics, livelihood exit and entry decisions were strongly affected by new access to regional and global markets. The natural resource implications of these livelihood decisions are potentially profound as they provide novel linkages and spatially-explicit feedbacks between terrestrial and marine ecosystems. Our findings support the need for more scientific inquiry in understanding trans-ecosystem tradeoffs due to linked-livelihood transitions as well as the need for a trans-ecosystem approach to natural resource management and development policy in rapidly changing coastal regions.

Coastal livelihood transitions under globalization with implications for trans-ecosystem interactions.

Directory of Open Access Journals (Sweden)

Daniel B Kramer

Full Text Available Anthropogenic threats to natural systems can be exacerbated due to connectivity between marine, freshwater, and terrestrial ecosystems, complicating the already daunting task of governance across the land-sea interface. Globalization, including new access to markets, can change social-ecological, land-sea linkages via livelihood responses and adaptations by local people. As a first step in understanding these trans-ecosystem effects, we examined exit and entry decisions of artisanal fishers and smallholder farmers on the rapidly globalizing Caribbean coast of Nicaragua. We found that exit and entry decisions demonstrated clear temporal and spatial patterns and that these decisions differed by livelihood. In addition to household characteristics, livelihood exit and entry decisions were strongly affected by new access to regional and global markets. The natural resource implications of these livelihood decisions are potentially profound as they provide novel linkages and spatially-explicit feedbacks between terrestrial and marine ecosystems. Our findings support the need for more scientific inquiry in understanding trans-ecosystem tradeoffs due to linked-livelihood transitions as well as the need for a trans-ecosystem approach to natural resource management and development policy in rapidly changing coastal regions.

Meteorological constraints on oceanic halocarbons above the Peruvian upwelling

Directory of Open Access Journals (Sweden)

S. Fuhlbrügge

2016-09-01

Full Text Available During a cruise of R/V METEOR in December 2012 the oceanic sources and emissions of various halogenated trace gases and their mixing ratios in the marine atmospheric boundary layer (MABL were investigated above the Peruvian upwelling. This study presents novel observations of the three very short lived substances (VSLSs – bromoform, dibromomethane and methyl iodide – together with high-resolution meteorological measurements, Lagrangian transport and source–loss calculations. Oceanic emissions of bromoform and dibromomethane were relatively low compared to other upwelling regions, while those for methyl iodide were very high. Radiosonde launches during the cruise revealed a low, stable MABL and a distinct trade inversion above acting as strong barriers for convection and vertical transport of trace gases in this region. Observed atmospheric VSLS abundances, sea surface temperature, relative humidity and MABL height correlated well during the cruise. We used a simple source–loss estimate to quantify the contribution of oceanic emissions along the cruise track to the observed atmospheric concentrations. This analysis showed that averaged, instantaneous emissions could not support the observed atmospheric mixing ratios of VSLSs and that the marine background abundances below the trade inversion were significantly influenced by advection of regional sources. Adding to this background, the observed maximum emissions of halocarbons in the coastal upwelling could explain the high atmospheric VSLS concentrations in combination with their accumulation under the distinct MABL and trade inversions. Stronger emissions along the nearshore coastline likely added to the elevated abundances under the steady atmospheric conditions. This study underscores the importance of oceanic upwelling and trade wind systems on the atmospheric distribution of marine VSLS emissions.

Meteorological constraints on oceanic halocarbons above the Peruvian upwelling

Science.gov (United States)

Fuhlbrügge, Steffen; Quack, Birgit; Atlas, Elliot; Fiehn, Alina; Hepach, Helmke; Krüger, Kirstin

2016-09-01

During a cruise of R/V METEOR in December 2012 the oceanic sources and emissions of various halogenated trace gases and their mixing ratios in the marine atmospheric boundary layer (MABL) were investigated above the Peruvian upwelling. This study presents novel observations of the three very short lived substances (VSLSs) - bromoform, dibromomethane and methyl iodide - together with high-resolution meteorological measurements, Lagrangian transport and source-loss calculations. Oceanic emissions of bromoform and dibromomethane were relatively low compared to other upwelling regions, while those for methyl iodide were very high. Radiosonde launches during the cruise revealed a low, stable MABL and a distinct trade inversion above acting as strong barriers for convection and vertical transport of trace gases in this region. Observed atmospheric VSLS abundances, sea surface temperature, relative humidity and MABL height correlated well during the cruise. We used a simple source-loss estimate to quantify the contribution of oceanic emissions along the cruise track to the observed atmospheric concentrations. This analysis showed that averaged, instantaneous emissions could not support the observed atmospheric mixing ratios of VSLSs and that the marine background abundances below the trade inversion were significantly influenced by advection of regional sources. Adding to this background, the observed maximum emissions of halocarbons in the coastal upwelling could explain the high atmospheric VSLS concentrations in combination with their accumulation under the distinct MABL and trade inversions. Stronger emissions along the nearshore coastline likely added to the elevated abundances under the steady atmospheric conditions. This study underscores the importance of oceanic upwelling and trade wind systems on the atmospheric distribution of marine VSLS emissions.

A Holocene record of ocean productivity and upwelling from the northern California continental slope

Science.gov (United States)

Addison, Jason A.; Barron, John A.; Finney, Bruce P.; Kusler, Jennifer E.; Bukry, David; Heusser, Linda E.; Alexander, Clark R.

2018-01-01

The Holocene upwelling history of the northern California continental slope is examined using the high-resolution record of TN062-O550 (40.9°N, 124.6°W, 550 m water depth). This 7-m-long marine sediment core spans the last ∼7500 years, and we use it to test the hypothesis that marine productivity in the California Current System (CCS) driven by coastal upwelling has co-varied with Holocene millennial-scale warm intervals. A combination of biogenic sediment concentrations (opal, total organic C, and total N), stable isotopes (organic matter δ13C and bulk sedimentary δ15N), and key microfossil indicators of upwelling were used to test this hypothesis. The record of biogenic accumulation in TN062-O550 shows considerable Holocene variability despite being located within 50 km of the mouth of the Eel River, which is one of the largest sources of terrigenous sediment to the Northeast Pacific Ocean margin. A key time interval beginning at ∼2900 calibrated years before present (cal yr BP) indicates the onset of modern upwelling in the CCS, and this period also corresponds to the most intense period of upwelling in the last 7500 years. When these results are placed into a regional CCS context during the Holocene, it was found that the timing of upwelling intensification at TN062-O550 corresponds closely to that seen at nearby ODP Site 1019, as well as in the Santa Barbara Basin of southern California. Other CCS records with less refined age control show similar results, which suggest late Holocene upwelling intensification may be synchronous throughout the CCS. Based on the strong correspondence between the alkenone sea surface temperature record at ODP Site 1019 and the onset of late Holocene upwelling in northern California, we suggest that CCS warming may be conducive to upwelling intensification, though future changes are unclear as the mechanisms forcing SST variability may differ.

Using models in Integrated Ecosystem Assessment of coastal areas

Science.gov (United States)

Solidoro, Cosimo; Bandelj, Vinko; Cossarini, Gianpiero; Melaku Canu, Donata; Libralato, Simone

2014-05-01

Numerical Models can greatly contribute to integrated ecological assessment of coastal and marine systems. Indeed, models can: i) assist in the identification of efficient sampling strategy; ii) provide space interpolation and time extrapolation of experiemtanl data which are based on the knowedge on processes dynamics and causal realtionships which is coded within the model, iii) provide estimates of hardly measurable indicators. Furthermore model can provide indication on potential effects of implementation of alternative management policies. Finally, by providing a synthetic representation of an ideal system, based on its essential dynamic, model return a picture of ideal behaviour of a system in the absence of external perturbation, alteration, noise, which might help in the identification of reference behaivuor. As an important example, model based reanalyses of biogeochemical and ecological properties are an urgent need for the estimate of the environmental status and the assessment of efficacy of conservation and environmental policies, also with reference to the enforcement of the European MSFD. However, the use of numerical models, and particularly of ecological models, in modeling and in environmental management still is far from be the rule, possibly because of a lack in realizing the benefits which a full integration of modeling and montoring systems might provide, possibly because of a lack of trust in modeling results, or because many problems still exists in the development, validation and implementation of models. For istance, assessing the validity of model results is a complex process that requires the definition of appropriate indicators, metrics, methodologies and faces with the scarcity of real-time in-situ biogeochemical data. Furthermore, biogeochemical models typically consider dozens of variables which are heavily undersampled. Here we show how the integration of mathematical model and monitoring data can support integrated ecosystem

High-resolution climate of the past ∼7300 years of coastal northernmost California: Results from diatoms, silicoflagellates, and pollen

Science.gov (United States)

Barron, John A.; Bukry, David; Heusser, Linda E.; Addison, Jason A.; Alexander, Clark R.

2018-01-01

Piston core TN062-O550, collected about 33 km offshore of Eureka, California, contains a high-resolution record of the climate and oceanography of coastal northernmost California during the past ∼7.34 kyr. Chronology established by nine AMS ages on a combination of planktic foraminifers, bivalve shell fragments, and wood yields a mean sedimentation rate of 103 cm kyr−1. Marine proxies (diatoms and silicoflagellates) and pollen transported by the nearby Eel River reveal a stepwise development of both modern offshore surface water oceanography and coastal arboreal ecosystems. Beginning at ∼5.4 cal ka the relative abundance of coastal redwood pollen, a proxy for coastal fog, displays a two fold increase suggesting enhanced coastal upwelling. A decline in the relative contribution of subtropical diatoms at ∼5.0 cal ka implies cooling of sea surface temperatures (SSTs). At ∼3.6 cal ka an increase in the relative abundance of alder and oak at the expense of coastal redwood likely signals intensified riverine transport of pollen from inland environments. Cooler offshore SSTs and increased precipitation characterize the interval between ∼3.6 and 2.8 cal ka. A rapid, stepwise change in coastal climatology and oceanography occurs between ∼2.8 and 2.6 cal ka that suggests an enhanced expression of modern Pacific Decadal Oscillation-like (PDO) cycles. A three-fold increase in the relative abundance of the subtropical diatom Fragilariopsis doliolus at 2.8 cal ka appears to mark an abrupt warming of winter SSTs. Soon afterwards at 2.6 cal ka, a two fold increase in the relative abundance of coastal redwood pollen is suggestive of an abrupt intensification of spring upwelling. After ∼2.8 cal ka a sequence of cool-warm, PDO-like cycles occurs wherein cool cycles are characterized by relative abundance increases in coastal redwood pollen and decreased contributions of subtropical diatoms, whereas opposite proxy trends distinguish warm cycles.

Wind influence on a coastal buoyant outflow

Science.gov (United States)

Whitney, Michael M.; Garvine, Richard W.

2005-03-01

This paper investigates the interplay between river discharge and winds in forcing coastal buoyant outflows. During light winds a plume influenced by the Earth's rotation will flow down shelf (in the direction of Kelvin wave propagation) as a slender buoyancy-driven coastal current. Downwelling favorable winds augment this down-shelf flow, narrow the plume, and mix the water column. Upwelling favorable winds drive currents that counter the buoyancy-driven flow, spread plume waters offshore, and rapidly mix buoyant waters. Two criteria are developed to assess the wind influence on a buoyant outflow. The wind strength index (Ws) determines whether a plume's along-shelf flow is in a wind-driven or buoyancy-driven state. Ws is the ratio of the wind-driven and buoyancy-driven along-shelf velocities. Wind influence on across-shelf plume structure is rated with a timescale (ttilt) for the isopycnal tilting caused by wind-driven Ekman circulation. These criteria are used to characterize wind influence on the Delaware Coastal Current and can be applied to other coastal buoyant outflows. The Delaware buoyant outflow is simulated for springtime high-river discharge conditions. Simulation results and Ws values reveal that the coastal current is buoyancy-driven most of the time (∣Ws∣ Wind events, however, overwhelm the buoyancy-driven flow (∣Ws∣ > 1) several times during the high-discharge period. Strong upwelling events reverse the buoyant outflow; they constitute an important mechanism for transporting fresh water up shelf. Across-shelf plume structure is more sensitive to wind influence than the along-shelf flow. Values of ttilt indicate that moderate or strong winds persisting throughout a day can modify plume width significantly. Plume widening during upwelling events is accompanied by mixing that can erase the buoyant outflow.

Impacts of the Nutrient Inputs from Riverine on the Dynamic and Community Structure of Fungal-like Protists in the Coastal Ocean Ecosystems

Science.gov (United States)

Duan, Y.; Wang, G.; Xie, N.

2016-02-01

The coastal ocean connects terrestrial (e.g., rivers and estuaries) with oceanic ecosystems and is considered as a major component of global carbon cycles and budgets. The coastal waters are featured with a high biodiversity and high primary production. Because of the excessive primary production, a large fraction of primary organic matter becomes available to consumers as detritus in the coastal waters. Bacterioplankton have long been known to play a key role in the degradation of this detritus, and export and storage of organic matter in the coastal ecosystems. However, the primary and secondary production and the carbon biogeochemical processes in the ecosystems are largely regulated by nutrient inputs from riverine and other anthropogenic activities through heterotrophic microbial communities. Thraustochytrids, commonly known as fungal-like protists, are unicellular heterotrophic protists and are recently acknowledged to play a significant role in ocean carbon cycling. Their abundance exceeds that of bacterioplankton in the most time of the year in the coastal waters of China. Also, their abundance and diversity are largely regulated by nutrients inputs from riverine and other anthropogenic activities. Our findings support that thraustochytrids are a dominant heterotrophic microbial group in the coastal waters. Evidently, thraustochytrids are an import, but neglected, component in microbial carbon biogeochemical processes of the coastal ocean.

Evaluation of the ecological integrity and ecosystem health of three benthic networks influenced by coastal upwelling in the northern Chile

Science.gov (United States)

The ecological health of ecosystems relates to the maintenance or restoration of optimal system function when confronted with a disturbance. A healthy ecosystem is a prerequisite for ecological sustainability. Ecological integrity has been defined as an emergent property of ecosy...

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

Surface circulation and upwelling patterns around Sri Lanka

Science.gov (United States)

de Vos, A.; Pattiaratchi, C. B.; Wijeratne, E. M. S.

2013-09-01

Sri Lanka occupies a unique location within the equatorial belt in the northern Indian Ocean with the Arabian Sea on its western side and the Bay of Bengal on its eastern side. The region is characterised by bi-annually reversing monsoon winds resulting from seasonal differential heating and cooling of the continental land mass and the ocean. This study explored elements of the dynamics of the surface circulation and coastal upwelling in the waters around Sri Lanka using satellite imagery and the Regional Ocean Modelling System (ROMS) configured to the study region and forced with ECMWF interim data. The model was run for 2 yr to examine the seasonal and shorter term (∼10 days) variability. The results confirmed the presence of the reversing current system in response to the changing wind field: the eastward flowing Southwest Monsoon Current (SMC) during the Southwest (SW) monsoon transporting 11.5 Sv and the westward flowing Northeast Monsoon Current (NMC) transporting 9.5 Sv during the Northeast (NE) monsoon, respectively. A recirculation feature located to the east of Sri Lanka during the SW monsoon, the Sri Lanka Dome, is shown to result from the interaction between the SMC and the Island of Sri Lanka. Along the eastern and western coasts, during both monsoon periods, flow is southward converging along the south coast. During the SW monsoon the Island deflects the eastward flowing SMC southward whilst along the east coast the southward flow results from the Sri Lanka Dome recirculation. The major upwelling region, during both monsoon periods, is located along the south coast and is shown to be due to flow convergence and divergence associated with offshore transport of water. Higher surface chlorophyll concentrations were observed during the SW monsoon. The location of the flow convergence and hence the upwelling centre was dependent on the relative strengths of wind driven flow along the east and west coasts: during the SW (NE) monsoon the flow along the

High resolution projections for the western Iberian coastal low level jet in a changing climate

Science.gov (United States)

Soares, Pedro M. M.; Lima, Daniela C. A.; Cardoso, Rita M.; Semedo, Alvaro

2017-09-01

The Iberian coastal low-level jet (CLLJ) is one of the less studied boundary layer wind jet features in the Eastern Boundary Currents Systems (EBCS). These regions are amongst the most productive ocean ecosystems, where the atmosphere-land-ocean feedbacks, which include marine boundary layer clouds, coastal jets, upwelling and inland soil temperature and moisture, play an important role in defining the regional climate along the sub-tropical mid-latitude western coastal areas. Recently, the present climate western Iberian CLLJ properties were extensively described using a high resolution regional climate hindcast simulation. A summer maximum frequency of occurrence above 30 % was found, with mean maximum wind speeds around 15 ms-1, between 300 and 400 m heights (at the jet core). Since the 1990s the climate change impact on the EBCS is being studied, nevertheless some lack of consensus still persists regarding the evolution of upwelling and other components of the climate system in these areas. However, recently some authors have shown that changes are to be expected concerning the timing, intensity and spatial homogeneity of coastal upwelling, in response to future warming, especially at higher latitudes, namely in Iberia and Canaries. In this study, the first climate change assessment study regarding the Western Iberian CLLJ, using a high resolution (9 km) regional climate simulation, is presented. The properties of this CLLJ are studied and compared using two 30 years simulations: one historical simulation for the 1971-2000 period, and another simulation for future climate, in agreement with the RCP8.5 scenario, for the 2071-2100 period. Robust and consistent changes are found: (1) the hourly frequency of occurrence of the CLLJ is expected to increase in summer along the western Iberian coast, from mean maximum values of around 35 % to approximately 50 %; (2) the relative increase of the CLLJ frequency of occurrence is higher in the north off western Iberia; (3

Urgent and Compelling Need for Coastal and Inland Aquatic Ecosystem Research Using Space-Based Sensors

Science.gov (United States)

Otis, D. B.; Muller-Karger, F. E.; Hestir, E.; Turpie, K. R.; Roberts, D. A.; Frouin, R.; Goodman, J.; Schaeffer, B. A.; Franz, B. A.; Humm, D. C.

2016-12-01

Coastal and inland waters and associated aquatic habitats, including wetlands, mangroves, submerged grasses, and coral reefs, are some of the most productive and diverse ecosystems on the planet. They provide services critical to human health, safety, and prosperity. Yet, they are highly vulnerable to changes in climate and other anthropogenic pressures. With a global population of over seven billion people and climbing, and a warming atmosphere driven by carbon dioxide now in excess of 400 ppb, these services are at risk of rapidly diminishing globally. We know little about how these ecosystems function. We need to characterize short-term changes in the functional biodiversity and biogeochemical cycles of these coastal and wetland ecosystems, from canopy to benthos, and trace these changes to their underlying environmental influences. This requires an observation-based approach that covers coastal and inland aquatic ecosystems in a repeated, synoptic manner. Space-borne sensing systems can provide this capability, supported by coordinated in situ calibration and product validation activities. The design requires high temporal resolution (weekly or better), medium spatial resolution (30 m pixels at nadir to complement Landsat-class sensors), and highly sensitive, ocean-color radiometric quality, high resolution spectroscopy with Visible and Short-Wave IR bands (order of 10 nm or better) to assess both atmospheric correction parameters and land vegetation composition. The strategy needs to include sunglint avoidance schemes, and methods to maximize signal to noise ratios and temporal coverage of aquatic areas. We describe such a system, and urge the U.S. to implement such an observing strategy in the short-term and sustain it for the benefit of humankind.

Drought and coastal ecosystems: an assessment of decision maker needs for information

Science.gov (United States)

Kirsten Lackstrom; Amanda Brennan; Kirstin Dow

2016-01-01

The National Integrated Drought Information System (NIDIS) is in the process of developing drought early warning systems in areas of the U.S. where the development and coordination of drought information is needed. In summer 2012, NIDIS launched a pilot program in North and South Carolina, addressing the uniqueness of drought impacts on coastal ecosystems.

Oceans and Human Health: Linking Ocean, Organism, and Human Health for Sustainable Management of Coastal Ecosystems

Science.gov (United States)

Sandifer, P. A.; Trtanj, J.; Collier, T. K.

2012-12-01

Scientists and policy-makers are increasingly recognizing that sustainable coastal communities depend on healthy and resilient economies, ecosystems, and people, and that the condition or "health" of the coastal ocean and humans are intimately and inextricably connected. A wealth of ecosystem services provided by ocean and coastal environments are crucial for human survival and well being. Nonetheless, the health of coastal communities, their economies, connected ecosystems and ecosystem services, and people are under increasing threats from health risks associated with environmental degradation, climate change, and unwise land use practices, all of which contribute to growing burdens of naturally-occurring and introduced pathogens, noxious algae, and chemical contaminants. The occurrence, frequency, intensity, geographic range, and number and kinds of ocean health threats are increasing, with concomitant health and economic effects and eroding public confidence in the safety and wholesomeness of coastal environments and resources. Concerns in the research and public health communities, many summarized in the seminal 1999 NRC Report, From Monsoons to Microbes and the 2004 final report of the US Commission on Ocean Policy, resulted in establishment of a new "meta-discipline" known as Oceans and Human Health (OHH). OHH brings together practitioners in oceanography, marine biology, ecology, biomedical science, medicine, economics and other social sciences, epidemiology, environmental management, and public health to focus on water- and food-borne causes of human and animal illnesses associated with ocean and coastal systems and on health benefits of seafood and other marine products. It integrates information across multiple disciplines to increase knowledge of ocean health risks and benefits and communicate such information to enhance public safety. Recognizing the need for a comprehensive approach to ocean health threats and benefits, Congress passed the Oceans and

Surface mixing and biological activity in the four Eastern Boundary Upwelling Systems

Directory of Open Access Journals (Sweden)

V. Rossi

2009-08-01

Full Text Available Eastern Boundary Upwelling Systems (EBUS are characterized by a high productivity of plankton associated with large commercial fisheries, thus playing key biological and socio-economical roles. Since they are populated by several physical oceanic structures such as filaments and eddies, which interact with the biological processes, it is a major challenge to study this sub- and mesoscale activity in connection with the chlorophyll distribution. The aim of this work is to make a comparative study of these four upwelling systems focussing on their surface stirring, using the Finite Size Lyapunov Exponents (FSLEs, and their biological activity, based on satellite data. First, the spatial distribution of horizontal mixing is analysed from time averages and from probability density functions of FSLEs, which allow us to divide each areas in two different subsystems. Then we studied the temporal variability of surface stirring focussing on the annual and seasonal cycle. We also proposed a ranking of the four EBUS based on the averaged mixing intensity. When investigating the links with chlorophyll concentration, the previous subsystems reveal distinct biological signatures. There is a global negative correlation between surface horizontal mixing and chlorophyll standing stocks over the four areas. To try to better understand this inverse relationship, we consider the vertical dimension by looking at the Ekman-transport and vertical velocities. We suggest the possibility of a changing response of the phytoplankton to sub/mesoscale turbulence, from a negative effect in the very productive coastal areas to a positive one in the open ocean. This study provides new insights for the understanding of the variable biological productivity in the ocean, which results from both dynamics of the marine ecosystem and of the 3-D turbulent medium.

Hot-spots of primary productivity: An Alternative interpretation to Conventional upwelling models

Science.gov (United States)

van Ruth, Paul D.; Ganf, George G.; Ward, Tim M.

2010-12-01

The eastern Great Australian Bight (EGAB) forms part of the Southern and Indian Oceans and is an area of high ecological and economic importance. Although it supports a commercial fishery, quantitative estimates of the primary productivity underlying this industry are open to debate. Estimates range from 500 mg C m -2 day -1. Part of this variation may be due to the unique upwelling circulation of shelf waters in summer/autumn (November-April), which shares some similarities with highly productive eastern boundary current upwelling systems, but differs due to the influence of a northern boundary current, the Flinders current, and a wide continental shelf. This study examines spatial variations in primary productivity in the EGAB during the upwelling seasons of 2005 and 2006. Daily integral productivity calculated using the vertically generalised production model (VGPM) showed a high degree of spatial variation. Productivity was low (modelled with the VGPM, which uses surface measures of phytoplankton biomass to calculate productivity. Macro-nutrient concentrations could not be used to explain the difference in the low and high productivities (silica > 1 μmol L -1, nitrate/nitrite > 0.4 μmol L -1, phosphate > 0.1 μmol L -1). Mixing patterns or micro-nutrient concentrations are possible explanations for spatial variations in primary productivity in the EGAB. On a global scale, daily rates of primary productivity of the EGAB lie between the highly productive eastern boundary current upwelling systems, and less productive coastal regions of western and south eastern Australia, and the oligotrophic ocean. However, daily productivity rates in the upwelling hotspots of the EGAB rival productivities in Benguela and Humboldt currents.

The capacities of institutions for the integration of ecosystem services in coastal strategic planning: The case of Jiaozhou Bay

NARCIS (Netherlands)

Li, Ruiqian; Li, Yongfu; Woltjer, Johan; van den Brink, Margo

2015-01-01

This paper explains how the practice of integrating ecosystem-service thinking (i.e., ecological benefits for human beings) and institutions (i.e., organisations, policy rules) is essential for coastal spatial planning. Adopting an integrated perspective on ecosystem services (ESs) both helps

Coastal upwelling ecosystems are often identified as regions ...

African Journals Online (AJOL)

spamer

... are often identified as regions susceptible to seasonal blooms of harmful ... that the bay acts as a net importer of bottom water and net exporter of surface waters over a synoptic cycle. This ... waves or wind stress on the surface friction layer.

Currents and upwelling along the Latium coasts in the Central Tyrrhenian Sea (western Mediterranean

Directory of Open Access Journals (Sweden)

V. Rossi

1995-04-01

Full Text Available In this study, springtime coastal currents along the Latium coast and their relation to external forcings, mainly wind stress curl and atmospheric pressure, are analysed. As a main result, we find that hydrographical measurements reveal currents parallel to the bottom isobaths, but with isopycnal sloping upwards towards the coast, suggesting the importance of upwellings in determining the coastal currents. This is confirmed by thermal satellite data showing the presence of a ~10-km-wide patch of cold water east of Mount Argentario, i.e. a cyclonic vortex. The current meter data give rather small values of the time-averaged alongshore velocities (~2 cm s–1 for most current meters and ~3 cm s–1 for the current meter placed immediately off the Argentario and also smaller values for the offshore velocities. The correlation between these two types of currents is rather poor; this is also due to the variability characteristic of a wind-induced upwelling. Finally, we obtain a value of 0.74 for the correlation between the alongshore current (first mode of Empirical Orthogonal Functions decomposition and the wind stress if a 23-h time lag is assumed.

Changes in the partial pressure of carbon dioxide in the Mauritanian–Cap Vert upwelling region between 2005 and 2012

Directory of Open Access Journals (Sweden)

M. González-Dávila

2017-08-01

Full Text Available Coastal upwellings along the eastern margins of major ocean basins represent regions of large ecological and economic importance due to the high biological productivity. The role of these regions for the global carbon cycle makes them essential in addressing climate change. The physical forcing of upwelling processes that favor production in these areas are already being affected by global warming, which will modify the intensity of upwelling and, consequently, the carbon dioxide cycle. Here, we present monthly high-resolution surface experimental data for temperature and partial pressure of carbon dioxide in one of the four most important upwelling regions of the planet, the Mauritanian–Cap Vert upwelling region, from 2005 to 2012. This data set provides direct evidence of seasonal and interannual changes in the physical and biochemical processes. Specifically, we show an upwelling intensification and an increase of 0.6 Tg yr−1 in CO2 outgassing due to increased wind speed, despite increased primary productivity. This increase in CO2 outgassing together with the observed decrease in sea surface temperature at the location of the Mauritanian Cap Blanc, 21° N, produced a pH rate decrease of −0.003 ± 0.001 yr−1.

Development of a 3D coupled physical-biogeochemical model for the Marseille coastal area (NW Mediterranean Sea: what complexity is required in the coastal zone?

Directory of Open Access Journals (Sweden)

Marion Fraysse

Full Text Available Terrestrial inputs (natural and anthropogenic from rivers, the atmosphere and physical processes strongly impact the functioning of coastal pelagic ecosystems. The objective of this study was to develop a tool for the examination of these impacts on the Marseille coastal area, which experiences inputs from the Rhone River and high rates of atmospheric deposition. Therefore, a new 3D coupled physical/biogeochemical model was developed. Two versions of the biogeochemical model were tested, one model considering only the carbon (C and nitrogen (N cycles and a second model that also considers the phosphorus (P cycle. Realistic simulations were performed for a period of 5 years (2007-2011. The model accuracy assessment showed that both versions of the model were able of capturing the seasonal changes and spatial characteristics of the ecosystem. The model also reproduced upwelling events and the intrusion of Rhone River water into the Bay of Marseille well. Those processes appeared to greatly impact this coastal oligotrophic area because they induced strong increases in chlorophyll-a concentrations in the surface layer. The model with the C, N and P cycles better reproduced the chlorophyll-a concentrations at the surface than did the model without the P cycle, especially for the Rhone River water. Nevertheless, the chlorophyll-a concentrations at depth were better represented by the model without the P cycle. Therefore, the complexity of the biogeochemical model introduced errors into the model results, but it also improved model results during specific events. Finally, this study suggested that in coastal oligotrophic areas, improvements in the description and quantification of the hydrodynamics and the terrestrial inputs should be preferred over increasing the complexity of the biogeochemical model.

NASA COAST and OCEANIA Airborne Missions in Support of Ecosystem and Water Quality Research in the Coastal Zone

Science.gov (United States)

Guild, Liane S.; Hooker, Stanford B.; Kudela, Raphael; Morrow, John; Russell, Philip; Myers, Jeffrey; Dunagan, Stephen; Palacios, Sherry; Livingston, John; Negrey, Kendra;

The Humboldt Current System: Ecosystem components and processes, fisheries, and sediment studies

Science.gov (United States)

Montecino, Vivian; Lange, Carina B.

2009-12-01

In the Humboldt Current System (HCS), biological and non-biological components, ecosystem processes, and fisheries are known to be affected by multi-decadal, inter-annual, annual, and intra-seasonal scales. The interplay between atmospheric variability, the poleward undercurrent, the shallow oxygen minimum zone (OMZ), and the fertilizing effect of coastal upwelling and overall high primary production rates drive bio-physical interactions, the carbon biomass, and fluxes of gases and particulate and dissolved matter through the water column. Coastal upwelling (permanent and seasonally modulated off Peru and northern Chile, and markedly seasonal between 30°S and 40°S) is the key process responsible for the high biological productivity in the HCS. At present, the western coast of South America produces more fish per unit area than any other region in the world ocean (i.e. ∼7.5 × 10 6 t of anchoveta were landed in 2007). Climate changes on different temporal scales lead to alterations in the distribution ranges of anchoveta and sardine populations and shifts in their dominance throughout the HCS. The factors affecting the coastal marine ecosystem that reverberate in the fisheries are crucial from a social perspective, since the economic consequences of mismanagement can be severe. Fish remains are often well-preserved in sediment settings under the hypoxic conditions of the OMZ off Peru and Chile, and reveal multi-decadal variability and centennial-scale changes in fish populations. Sediment studies from the Chilean continental margin encompassing the last 20,000 years of deposition reveal changes in sub-surface conditions in the HCS during deglaciation, interpreted to include: a major reorganization of the OMZ; a deglacial increase in denitrification decoupled from local marine productivity; and higher deglacial and Holocene paleoproductivities compared to the Last Glacial Maximum in central-south Chile (35-37°S) while this scheme is reversed for north

Capacity building for tropical coastal ecosystems management using a dynamic teaching model

DEFF Research Database (Denmark)

Lindberg, Annika Büchert; Nielsen, Thomas; Macintosh, Donald

2008-01-01

This learning opportunity illustrates effective capacity building through a dynamic teaching model that involves you and gives you personal experiences. The teaching model is easy to adapt to local environments and the learning opportunity is relevant to everyone working in coastal natural resource...... in combining knowledge and methods and applying these in a real life situation. Objectives: The participants will apply the acquired knowledge of ecosystems and project management tools when describing ecosystem services and when planning a project The participants will act as different stakeholders during...... the role play and hereby gain experience from a situation mimicking real life project situation.; The participants will experience how dynamic teaching can improve capacity building....

Marine and coastal ecosystem services on the science–policy–practice nexus: challenges and opportunities from 11 European case studies

NARCIS (Netherlands)

Drakou, E.G.; Kermagoret, C.; Liquete, C.; Ruiz-Frau, A.; Burkhard, K.; Lillebø, A.I.; van Oudenhoven, A.P.E.; Ballé-Béganton, J.; Rodrigues, J.G.; Nieminen, E.; Oinonen, S.; Ziemba, A.; Gissi, E.; Depellegrin, D.; Veidemane, K.; Ruskule, A.; Delangue, J.; Böhnke-Henrichs, A.; Boon, A.; Wenning, R.; Martino, S.; Hasler, B.; Termansen, M.; Rockel, M.; Hummel, H.; El Serafy, G.; Peev, P.

2017-01-01

We compared and contrasted 11 European case studies to identify challenges and opportunitiestoward the operationalization of marine and coastal ecosystem service (MCES) assessments inEurope. This work is the output of a panel convened by the Marine Working Group of theEcosystemServices Partnership

Ecosystem-based management of coastal zones in face of climate change impacts: Challenges and inequalities.

Science.gov (United States)

Fernandino, Gerson; Elliff, Carla I; Silva, Iracema R

2018-06-01

Climate change effects have the potential of affecting both ocean and atmospheric processes. These changes pose serious threats to the millions of people that live by the coast. Thus, the objective of the present review is to discuss how climate change is altering (and will continue to alter) atmospheric and oceanic processes, what are the main implications of these alterations along the coastline, and which are the ecosystem-based management (EBM) strategies that have been proposed and applied to address these issues. While ocean warming, ocean acidification and increasing sea level have been more extensively studied, investigations on the effects of climate change to wind and wave climates are less frequent. Coastal ecosystems and their respective natural resources will respond differently according to location, environmental drivers and coastal processes. EBM strategies have mostly concentrated on improving ecosystem services, which can be used to assist in mitigating climate change effects. The main challenge for developing nations regards gaps in information and scarcity of resources. Thus, for effective management and adaptive EBM strategies to be developed worldwide, information at a local level is greatly needed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of natural and human-induced hypoxia on coastal benthos

OpenAIRE

Levin, L. A.; Ekau, W.; Gooday, A. J.; Jorissen, F.; Middelburg, J. J.; Naqvi, S. W. A.; Neira, C.; Rabalais, N. N.; Zhang, J.

2009-01-01

Coastal hypoxia (<1.42 ml L⁻¹; 62.5 μM; 2 mg L⁻¹, approx. 30% oxygen saturation) occurs seasonally in many estuaries, fjords, and along open coasts subject to upwelling or excessive riverine nutrient input, and permanently in some isolated seas and marine basins. Underlying causes of hypoxia include enhanced nutrient input from natural causes (upwelling) or anthropogenic origin (eutrophication) and reduction of mixing by...

Metals content in surface waters of an upwelling system of the northern Humboldt Current (Mejillones Bay, Chile)

Science.gov (United States)

Valdés, Jorge; Román, Domingo; Alvarez, Gabriel; Ortlieb, Luc; Guiñez, Marcos

Physical-chemical parameters (temperature, salinity, dissolved oxygen, nutrients, and chlorophyll concentration) of surface waters were used to evaluate the influence of biological and physical processes over the metal concentrations (Cd, Ni, V, Mo, Mn, and Fe) in different periods of a normal annual cycle (June 2002 and April 2003), in Mejillones Bay (23° S), one of northern Chile's strongest upwelling cells. Two points were sampled every 2 months, but statistical analysis of these parameters did not show any spatial differences in surface water composition (annual average) in this bay. The order of total and dissolved metals by abundance (annual mean) in the Mejillones Bay surface waters during the sampling period was Cd Oxygen Minimum Zone which characterizes the Mejillones bay should have an important influence on surface distribution of trace metals and can explain the high temporal variability observed in most of the metals analyzed in this work. A two-box conceptual model is proposed to suggest possible influences on metals in surface waters of this coastal ecosystem.

Macro and micro plastics sorb and desorb metals and act as a point source of trace metals to coastal ecosystems.

Science.gov (United States)

Munier, B; Bendell, L I

2018-01-01

Nine urban intertidal regions in Burrard Inlet, Vancouver, British Columbia, Canada, were sampled for plastic debris. Debris included macro and micro plastics and originated from a wide diversity of uses ranging from personal hygiene to solar cells. Debris was characterized for its polymer through standard physiochemical characteristics, then subject to a weak acid extraction to remove the metals, zinc, copper, cadmium and lead from the polymer. Recently manufactured low density polyethylene (LDPE), nylon, polyethylene terephthalate (PET), polypropylene (PP), polystyrene (PS) and polyvinyl chloride (PVC) were subject to the same extraction. Data was statistically analyzed by appropriate parametric and non-parametric tests when needed with significance set at P Plastic debris will affect metals within coastal ecosystems by; 1) providing a sorption site (copper and lead), notably for PVC 2) desorption from the plastic i.e., the "inherent" load (cadmium and zinc) and 3) serving as a point source of acute trace metal exposure to coastal ecosystems. All three mechanisms will put coastal ecosystems at risk to the toxic effects of these metals.

Phytoplankton primary production in the world's estuarine-coastal ecosystems

Science.gov (United States)

Cloern, James E.; Foster, S.Q.; Kleckner, A.E.

2014-01-01

Estuaries are biogeochemical hot spots because they receive large inputs of nutrients and organic carbon from land and oceans to support high rates of metabolism and primary production. We synthesize published rates of annual phytoplankton primary production (APPP) in marine ecosystems influenced by connectivity to land – estuaries, bays, lagoons, fjords and inland seas. Review of the scientific literature produced a compilation of 1148 values of APPP derived from monthly incubation assays to measure carbon assimilation or oxygen production. The median value of median APPP measurements in 131 ecosystems is 185 and the mean is 252 g C m−2 yr−1, but the range is large: from −105 (net pelagic production in the Scheldt Estuary) to 1890 g C m−2 yr−1 (net phytoplankton production in Tamagawa Estuary). APPP varies up to 10-fold within ecosystems and 5-fold from year to year (but we only found eight APPP series longer than a decade so our knowledge of decadal-scale variability is limited). We use studies of individual places to build a conceptual model that integrates the mechanisms generating this large variability: nutrient supply, light limitation by turbidity, grazing by consumers, and physical processes (river inflow, ocean exchange, and inputs of heat, light and wind energy). We consider method as another source of variability because the compilation includes values derived from widely differing protocols. A simulation model shows that different methods reported in the literature can yield up to 3-fold variability depending on incubation protocols and methods for integrating measured rates over time and depth. Although attempts have been made to upscale measures of estuarine-coastal APPP, the empirical record is inadequate for yielding reliable global estimates. The record is deficient in three ways. First, it is highly biased by the large number of measurements made in northern Europe (particularly the Baltic region) and North America. Of the 1148

Warm water upwelling in the Cenozoic Era

Science.gov (United States)

Zhang, Y.

2017-12-01

Modern observations show that the occurrence of wind-driven upwelling is often tied to cold sea surface temperatures (SSTs). However, SST reconstructions indicate that globally, the upwelling regions were much warmer in the Miocene and Pliocene. This questions the overall strength of deep-water upwelling in the geological past, with important implications for the associated atmospheric, climatic and biogeochemical processes, and the fate of upwelling regions in a high-CO2 world. We recently showed that the eastern equatorial Pacific (EEP) was characterized by strong air-sea disequilibrium of CO2 during the late Miocene - Pliocene. Combined with export productivity proxies, we interpreted these as signs of vigorous upwelling. The upwelled waters were nutrient- and CO2-rich, but warm. The cause of the "excess" warming in the upwelling regions is linked to the source waters which originated from the higher latitudes. In other words, the reduced east (upwelling) to west (non-upwelling) temperature gradients along the equator in major ocean basins are rooted in the reduced meridional temperature gradients. To further test this hypothesis, we examine the history of the EEP and temperature gradients during the even-warmer Eocene - middle Miocene.

Natural ocean acidification at Papagayo upwelling system (north Pacific Costa Rica): implications for reef development

Science.gov (United States)

Sánchez-Noguera, Celeste; Stuhldreier, Ines; Cortés, Jorge; Jiménez, Carlos; Morales, Álvaro; Wild, Christian; Rixen, Tim

2018-04-01

Numerous experiments have shown that ocean acidification impedes coral calcification, but knowledge about in situ reef ecosystem response to ocean acidification is still scarce. Bahía Culebra, situated at the northern Pacific coast of Costa Rica, is a location naturally exposed to acidic conditions due to the Papagayo seasonal upwelling. We measured pH and pCO2 in situ during two non-upwelling seasons (June 2012, May-June 2013), with a high temporal resolution of every 15 and 30 min, respectively, using two Submersible Autonomous Moored Instruments (SAMI-pH, SAMI-CO2). These results were compared with published data from the 2009 upwelling season. Findings revealed that the carbonate system in Bahía Culebra shows a high temporal variability. Incoming offshore waters drive intra- and interseasonal changes. Lowest pH (7.8) and highest pCO2 (658.3 µatm) values measured during a cold-water intrusion event in the non-upwelling season were similar to those minimum values reported from upwelling season (pH = 7.8, pCO2 = 643.5 µatm), unveiling that natural acidification also occurs sporadically in the non-upwelling season. This affects the interaction of photosynthesis, respiration, calcification and carbonate dissolution and the resulting diel cycle of pH and pCO2 in the reefs of Bahía Culebra. During the non-upwelling season, the aragonite saturation state (Ωa) rises to values of > 3.3 and during the upwelling season falls below 2.5. The Ωa threshold values for coral growth were derived from the correlation between measured Ωa and coral linear extension rates which were obtained from the literature and suggest that future ocean acidification will threaten the continued growth of reefs in Bahía Culebra. These data contribute to building a better understanding of the carbonate system dynamics and coral reefs' key response (e.g., coral growth) to natural low-pH conditions, in upwelling areas in the eastern tropical Pacific and beyond.

[Multi-scenario simulation and prediction of ecosystem services as affected by urban expansion: A case study in coastal area of Tianjin, North China].

Science.gov (United States)

Huang, Huan-Chun; Yun, Ying-Xia; Miao, Zhan-Tang; Hao, Cui; Li, Hong-yuan

2013-03-01

Based on the modified Logistic-CA model, and taking the coastal area of Tianjin as a case, this paper simulated the spatial evolution patterns of ecosystem services as affected by the urban expansion in 2011-2020 under the scenarios of historical extrapolation, endogenous development, and exogenous development. Overall, the total ecosystem services of the study area under the three scenarios were generally the same, and the functional region with the lowest level ecosystem services had the identical spatial pattern. However, the spatial evolution patterns of the ecosystem services of the study area under the three scenarios had a great difference. The functional regions with lower-level ecosystem services grew in a cross-shaped pattern, with the Tanggu downtown as a center, and finally formed a full connectivity area along the Haihe River and coastal zone.

Defining seascapes for marine unconsolidated shelf sediments in an eastern boundary upwelling region: The southern Benguela as a case study

Science.gov (United States)

Karenyi, Natasha; Sink, Kerry; Nel, Ronel

2016-02-01

Marine unconsolidated sediment habitats, the largest benthic ecosystem, are considered physically controlled ecosystems driven by a number of local physical processes. Depth and sediment type are recognised key drivers of these ecosystems. Seascape (i.e., marine landscape) habitat classifications are based solely on consistent geophysical features and provide an opportunity to define unconsolidated sediment habitats based on processes which may vary in distribution through space and time. This paper aimed to classify unconsolidated sediment seascapes and explore their diversity in an eastern boundary upwelling region at the macro-scale, using the South African west coast as a case study. Physical variables such as sediment grain size, depth and upwelling-related variables (i.e., maximum chlorophyll concentration, austral summer bottom oxygen concentration and sediment organic carbon content) were included in the analyses. These variables were directly measured through sampling, or collated from existing databases and the literature. These data were analysed using multivariate Cluster, Principal Components Ordination and SIMPER analyses (in PRIMER 6 + with PERMANOVA add-in package). There were four main findings; (i) eight seascapes were identified for the South African west coast based on depth, slope, sediment grain size and upwelling-related variables, (ii) three depth zones were distinguished (inner, middle and outer shelf), (iii) seascape diversity in the inner and middle shelves was greater than the outer shelf, and (iv) upwelling-related variables were responsible for the habitat diversity in both inner and middle shelves. This research demonstrates that the inclusion of productivity and its related variables, such as hypoxia and sedimentary organic carbon, in seascape classifications will enhance the ability to distinguish seascapes on continental shelves, where productivity is most variable.

Seal carrion is a predictable resource for coastal ecosystems

Science.gov (United States)

Quaggiotto, Maria-Martina; Barton, Philip S.; Morris, Christopher D.; Moss, Simon E. W.; Pomeroy, Patrick P.; McCafferty, Dominic J.; Bailey, David M.

2018-04-01

The timing, magnitude, and spatial distribution of resource inputs can have large effects on dependent organisms. Few studies have examined the predictability of such resources and no standard ecological measure of predictability exists. We examined the potential predictability of carrion resources provided by one of the UK's largest grey seal (Halichoerus grypus) colonies, on the Isle of May, Scotland. We used aerial (11 years) and ground surveys (3 years) to quantify the variability in time, space, quantity (kg), and quality (MJ) of seal carrion during the seal pupping season. We then compared the potential predictability of seal carrion to other periodic changes in food availability in nature. An average of 6893 kg of carrion •yr-1 corresponding to 110.5 × 103 MJ yr-1 was released for potential scavengers as placentae and dead animals. A fifth of the total biomass from dead seals was consumed by the end of the pupping season, mostly by avian scavengers. The spatial distribution of carcasses was similar across years, and 28% of the area containing >10 carcasses ha-1 was shared among all years. Relative standard errors (RSE) in space, time, quantity, and quality of carrion were all below 34%. This is similar to other allochthonous-dependent ecosystems, such as those affected by migratory salmon, and indicates high predictability of seal carrion as a resource. Our study illustrates how to quantify predictability in carrion, which is of general relevance to ecosystems that are dependent on this resource. We also highlight the importance of carrion to marine coastal ecosystems, where it sustains avian scavengers thus affecting ecosystem structure and function.

NASA COAST and OCEANIA Airborne Missions Support Ecosystem and Water Quality Research in the Coastal Zone

Science.gov (United States)

Guild, Liane; Kudela, Raphael; Hooker, Stanford; Morrow, John; Russell, Philip; Palacios, Sherry; Livingston, John M.; Negrey, Kendra; Torres-Perez, Juan; Broughton, Jennifer

2014-01-01

NASA has a continuing requirement to collect high-quality in situ data for the vicarious calibration of current and next generation ocean color satellite sensors and to validate the algorithms that use the remotely sensed observations. Recent NASA airborne missions over Monterey Bay, CA, have demonstrated novel above- and in-water measurement capabilities supporting a combined airborne sensor approach (imaging spectrometer, microradiometers, and a sun photometer). The results characterize coastal atmospheric and aquatic properties through an end-to-end assessment of image acquisition, atmospheric correction, algorithm application, plus sea-truth observations from state-of-the-art instrument systems. The primary goal is to demonstrate the following in support of calibration and validation exercises for satellite coastal ocean color products: 1) the utility of a multi-sensor airborne instrument suite to assess the bio-optical properties of coastal California, including water quality; and 2) the importance of contemporaneous atmospheric measurements to improve atmospheric correction in the coastal zone. The imaging spectrometer (Headwall) is optimized in the blue spectral domain to emphasize remote sensing of marine and freshwater ecosystems. The novel airborne instrument, Coastal Airborne In-situ Radiometers (C-AIR) provides measurements of apparent optical properties with high dynamic range and fidelity for deriving exact water leaving radiances at the land-ocean boundary, including radiometrically shallow aquatic ecosystems. Simultaneous measurements supporting empirical atmospheric correction of image data are accomplished using the Ames Airborne Tracking Sunphotometer (AATS-14). Flight operations are presented for the instrument payloads using the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter flown over Monterey Bay during the seasonal fall algal bloom in 2011 (COAST) and 2013 (OCEANIA) to support bio-optical measurements of

Coastal Ecosystem Assessment, Development and Creation of a Policy Tool using Unmanned Aerial Vehicles (UAVs) for: A Case Study of Western Puerto Rico Coastal Region

Science.gov (United States)

Munoz Barreto, J.; Pillich, J.; Aponte Bermúdez, L. D.; Torres Pagan, G.

2017-12-01

This project utilizes low-cost Unmanned Aerial Vehicles (UAVs) based systems for different applications, such as low-altitude (high resolution) aerial photogrammetry for aerial analysis of vegetation, reconstruction of beach topography and mapping coastal erosion to understand, and estimated ecosystem values. As part of this work, five testbeds coastal sites, designated as the Caribbean Littoral Aerial Surveillance System (CLASS), were established. The sites are distributed along western Puerto Rico coastline where population and industry (tourism) are very much clustered and dense along the coast. Over the past year, rapid post-storm deployment of UAV surveying has been successfully integrated into the CLASS sites, specifically at Rincon (Puerto Rico), where coastal erosion has raised the public and government concern over the past decades. A case study is presented here where we collected aerial photos before and after the swells caused by Hurricane Mathew (October 2016). We merged the point cloud obtained from the UAV photogrammetric assessment with topo-bathymetric data, to get a complete beach topography. Using the rectified and georeferenced UAV orthophotos, we identified the maximum wave runup for the pre-swell and post-swell events. Also, we used numerical modeling (X-Beach) to simulate the rate-of-change dynamics of the coastal zones and compare the model results to observed values (including multiple historic shoreline positions). In summary, our project has accomplished the first milestone which is the Development and Implementation of an Effective Shoreline Monitoring Program using UAVs. The activities of the monitoring program have enabled the collection of crucial data for coastal mapping along Puerto Rico's shorelines with emphasis on coastal erosion hot spots zones and ecosystem values. Our results highlight the potential of the synergy between UAVs, photogrammetry, and Geographic Information Systems to provide faster and low-cost reliable

Oceanographic features of the upwelling in front of Gaira's intent Magdalena Department, minor dry season of 2006

International Nuclear Information System (INIS)

Arevalo Martinez, Damian Leonardo; Franco Herrera, Andres

2008-01-01

In order to determine the influence of the ocean and atmospheric coupling dynamics on upwelling events, caused by Ekman's transport and by continental winds, as well as the possible fertilization effect produced by the increasing of the concentration of inorganic nutrients in coastal waters of Gaira's inlet, Magdalena department, during the minor dry season of 2006, atmospheric, oceanographic, and biological variables were measured by the implementation of the Eurelian method. A total of four samplings were carried out, among which two presented atmospheric and oceanic conditions that evidence the occurrence of upwelling events 48 hours before in response to strong winds coming from northeast (trade winds) and from the continent, whereas the other two samplings presented similar characteristics to those typical of rainy seasons. During this study, wind velocity and direction presented expected values during upwelling events caused by Ekman's transport and by continental winds (≥ 4.5 m/s, 26 Celsius degrade and 120 Celsius degrade, respectively), generating enough stress levels in the sea surface layer that could move it offshore (1.2 dynes/cm 2 ). During the days following the upwelling events, anomalies in water physical and chemical characteristics were observed, presenting low temperatures (26.1 +- 1.1 Celsius degrade), high salinity (36.0 +- 0.5) and, as a consequence, high densities (δ 26.31 +- 0.50), as well as low dissolved oxygen levels (4.04 +- 0.29 mL/L) and predominant subsaturation (84.3 +- 6.1 %) Inorganic nutrient concentration showed a relatively homogeneous behavior, keeping low nitrite (0.35 +- 0.02 μM) and phosphate (0.30 +- 0.01 μM) levels during all samplings, whereas the mean ammonium concentration was relatively high (1.08 +- 0.11 μM). In contrast, nitrate levels were high during all samplings, with higher values corresponding to upwelling events (9.48 +- 0.49 μM), although variation was not statistically significative. Phytoplanktonic

Human activities and climate variability drive fast-paced change across the world's estuarine-coastal ecosystems

Science.gov (United States)

Cloern, James E.; Abreu, Paulo C.; Carstensen, Jacob; Chauvaud, Laurent; Elmgren, Ragnar; Grall, Jacques; Greening, Holly; Johansson, John O.R.; Kahru, Mati; Sherwood, Edward T.; Xu, Jie; Yin, Kedong

2016-01-01

Time series of environmental measurements are essential for detecting, measuring and understanding changes in the Earth system and its biological communities. Observational series have accumulated over the past 2–5 decades from measurements across the world's estuaries, bays, lagoons, inland seas and shelf waters influenced by runoff. We synthesize information contained in these time series to develop a global view of changes occurring in marine systems influenced by connectivity to land. Our review is organized around four themes: (i) human activities as drivers of change; (ii) variability of the climate system as a driver of change; (iii) successes, disappointments and challenges of managing change at the sea-land interface; and (iv) discoveries made from observations over time. Multidecadal time series reveal that many of the world's estuarine–coastal ecosystems are in a continuing state of change, and the pace of change is faster than we could have imagined a decade ago. Some have been transformed into novel ecosystems with habitats, biogeochemistry and biological communities outside the natural range of variability. Change takes many forms including linear and nonlinear trends, abrupt state changes and oscillations. The challenge of managing change is daunting in the coastal zone where diverse human pressures are concentrated and intersect with different responses to climate variability over land and over ocean basins. The pace of change in estuarine–coastal ecosystems will likely accelerate as the human population and economies continue to grow and as global climate change accelerates. Wise stewardship of the resources upon which we depend is critically dependent upon a continuing flow of information from observations to measure, understand and anticipate future changes along the world's coastlines.

Temporal development of coastal ecosystems in the Baltic Sea - an assessment of patterns and trends

DEFF Research Database (Denmark)

Olsson, Jens; Bergström, Lena; Tomczak, Maciej

2014-01-01

in the north, covers between two to five trophic levels per area, and include time series dating back to the early 1990s. Using multivariate analyses, we assess the temporal development of species abundance or biomass at different trophic levels in relation to the development of variables related to local...... and regional climate, hydrology, nutrient loading and fishing pressure. Our results highlight the relative timing of change in ecosystem structure and the development of key biological elements across areas. Besides describing the temporal development of coastal ecosystems in the Baltic Sea during the past two...

Erosi Pantai, Ekosistem Hutan Bakau dan Adaptasi Masyarakat Terhadap Bencana Kerusakan Pantai Di negara Tropis (Coastal Erosion, Mangrove Ecosystems and Community Adaptation to Coastal Disasters in Tropical Countries

Directory of Open Access Journals (Sweden)

Aji Ali Akbar

2017-05-01

Full Text Available ABSTRAK   Tulisan ini bertujuan untuk mengkaji terjadinya kerusakan lingkungan pantai di negara tropis dan sebagian negara subtropis akibat perilaku manusia. Perilaku manusia yang menyebabkan kerusakan lingkungan adalah memanfaatkan sumberdaya alam pesisir tanpa memperhatikan keberlanjutan sumber daya alam dan daya dukung lingkungannya. Kerusakan lingkungan pantai yang umum terjadi di negara tropis dan sebagian subtropis adalah erosi pantai dan degradasi ekosistem hutan bakau. Kerusakan lingkungan pantai ini akibat alih fungsi lahan menjadi jaringan jalan, permukiman, lahan pertanian/ perkebunan, pertambakan, dan pertambangan pasir. Kerusakan lingkungan pantai mempengaruhi kondisi sosial ekonomi masyarakat setempat seperti hilangnya badan jalan, permukiman, lahan pertanian, dan fasilitas umum akibat abrasi pantai. Upaya penanggulangan kerusakan lingkungan pantai sebagai bagian dari adaptasi manusia mempertahankan kehidupannya berupa pembangunan pemecah gelombang (breakwaters dan rehabilitasi ekosistem hutan bakau. Upaya penanggulangan bencana tersebut tentunya membutuhkan biaya yang besar dan waktu lama daripada upaya pencegahan. Oleh karena itu, perubahan pola pikir baik pemerintah dan masyarakat dalam memanfaatkan, mengelola dan melestarikan sumber daya alam perlu ditingkatkan melalui perbaikan informasi, ilmu pengetahuan, dan strategi perencanaan yang holistik. Kata kunci: erosi pantai, kerusakan ekosistem hutan bakau, alih fungsi lahan, pemecah gelombang, rehabilitasi ABSTRACT This paper aims to assess the coastal degradation in tropical and subtropical countries in part due to human behavior. Human behavior is causing coastal degradation is to utilize natural resources without regard to the sustainability of coastal natural resources and the carrying capacity of the environment. Degradation of coastal common in most tropical and subtropical countries are coastal erosion and degradation of mangrove ecosystems. This coastal degradation as a

Bioavailability and impact of effluents on coastal ecosystems

International Nuclear Information System (INIS)

Anon.

1976-01-01

The Bioavailability and Impact of Effluents on Coastal Ecosystems program was initiated in July 1974. The program's major objective was to bring together a multidisciplinary team of researchers to investigate the biogeochemical processes that control the transport, transfer, distribution, biological availability and toxicity of materials found in energy-related effluents. This year has been spent in planning the needed research tasks, assembling the necessary personnel and equipment, and initiating first stage research as defined by the program. The program is centered at the Marine Research Laboratory, Sequim, Washington, and involves scientists located at Sequim and Richland. The operating philosophy is to conduct the program at the Marine Research Laboratory and use equipment and expertise from Richland as a resource for studies that cannot be practically done at Sequim. The research described represents the first year's efforts by the investigators involved in the program

Major threats of pollution and climate change to global coastal ecosystems and enhanced management for sustainability

NARCIS (Netherlands)

Lu, Y.; Yuan, J.; Lu, X.; Su, Chao; Zhang, Y.; Wang, C.; Cao, X.; Li, Q.; Su, Jilan; Ittekkot, Venugopalan; Garbutt, Richard Angus; Bush, S.R.; Fletcher, Stephen; Wagey, Tonny; Kachur, Anatolii; Sweijd, Neville

2018-01-01

Coastal zone is of great importance in the provision of various valuable ecosystem services. However, it is also sensitive and vulnerable to environmental changes due to high human populations and interactions between the land and ocean. Major threats of pollution from over enrichment of nutrients,

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

Intraseasonal patterns in coastal plankton biomass off central Chile derived from satellite observations and a biochemical model

Science.gov (United States)

Gomez, Fabian A.; Spitz, Yvette H.; Batchelder, Harold P.; Correa-Ramirez, Marco A.

2017-10-01

Subseasonal (5-130 days) environmental variability can strongly affect plankton dynamics, but is often overlooked in marine ecology studies. We documented the main subseasonal patterns of plankton biomass in the coastal upwelling system off central Chile, the southern part of the Humboldt System. Subseasonal variability was extracted from temporal patterns in satellite data of wind stress, sea surface temperature, and chlorophyll from the period 2003-2011, and from a realistically forced eddy-resolving physical-biochemical model from 2003 to 2008. Although most of the wind variability occurs at submonthly frequencies (< 30 days), we found that the dominant subseasonal pattern of phytoplankton biomass is within the intraseasonal band (30-90 days). The strongest intraseasonal coupling between wind and plankton is in spring-summer, when increased solar radiation enhances the phytoplankton response to upwelling. Biochemical model outputs show intraseasonal shifts in plankton community structure, mainly associated with the large fluctuations in diatom biomass. Diatom biomass peaks near surface during strong upwelling, whereas small phytoplankton biomass peaks at subsurface depths during relaxation or downwelling periods. Strong intraseasonally forced changes in biomass and species composition could strongly impact trophodynamics connections in the ecosystem, including the recruitment of commercially important fish species such as common sardine and anchovy. The wind-driven variability of chlorophyll concentration was connected to mid- and high-latitude atmospheric anomalies, which resemble disturbances with frequencies similar to the tropical Madden-Julian Oscillation.

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

The presence of the Indo-Pacific symbiont-bearing foraminifer Amphistegina lobifera in Greek coastal ecosystems (Aegean Sea, Eastern Mediterranean

Directory of Open Access Journals (Sweden)

M.V. TRIANTAPHYLLOU

2009-12-01

Full Text Available During the last decades, hundreds of species of Indo-Pacific origin from the Red Sea have traversed the Suez Canal and settled in the Eastern Mediterranean. Nowadays, Amphistegina lobifera Larsen, is known to be a successful immigrant that is widely distributed in the coastal ecosystems of the Eastern Mediterranean Sea. Amphistegina is the most common epiphytic, symbiont- bearing large foraminifer. In this study we provide additional data on the presence of this species in the coastal ecosystems of Aegean Sea, Greece. The high relative abundance of A. lobifera is the result of very successful adaptation of this species to local conditions and suggests that it has become a significant part of the epiphytic foraminiferal fauna.

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

Science.gov (United States)

Kaneko, Korehisa; Matsushima, Hajime

2017-12-01

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

Megacities and large urban agglomerations in the coastal zone: interactions between atmosphere, land, and marine ecosystems.

Science.gov (United States)

von Glasow, Roland; Jickells, Tim D; Baklanov, Alexander; Carmichael, Gregory R; Church, Tom M; Gallardo, Laura; Hughes, Claire; Kanakidou, Maria; Liss, Peter S; Mee, Laurence; Raine, Robin; Ramachandran, Purvaja; Ramesh, R; Sundseth, Kyrre; Tsunogai, Urumu; Uematsu, Mitsuo; Zhu, Tong

2013-02-01

Megacities are not only important drivers for socio-economic development but also sources of environmental challenges. Many megacities and large urban agglomerations are located in the coastal zone where land, atmosphere, and ocean meet, posing multiple environmental challenges which we consider here. The atmospheric flow around megacities is complicated by urban heat island effects and topographic flows and sea breezes and influences air pollution and human health. The outflow of polluted air over the ocean perturbs biogeochemical processes. Contaminant inputs can damage downstream coastal zone ecosystem function and resources including fisheries, induce harmful algal blooms and feedback to the atmosphere via marine emissions. The scale of influence of megacities in the coastal zone is hundreds to thousands of kilometers in the atmosphere and tens to hundreds of kilometers in the ocean. We list research needs to further our understanding of coastal megacities with the ultimate aim to improve their environmental management.

Accumulation of Carbonates Contributes to Coastal Vegetated Ecosystems Keeping Pace With Sea Level Rise in an Arid Region (Arabian Peninsula)

KAUST Repository

Saderne, Vincent; Cusack, Michael; Almahasheer, Hanan; Serrano, Oscar; Masqué , Pere; Arias-Ortiz, Ariane; Krishnakumar, Periyadan Kadinjappalli; Rabaoui, Lotfi; Qurban, Mohammad Ali; Duarte, Carlos M.

2018-01-01

Anthropogenic sea level rise (SLR) presents one of the greatest risks to human lives and infrastructures. Coastal vegetated ecosystems, that is, tidal marshes, seagrass meadows, and mangrove forests, elevate the seabed through soil accretion, providing a natural coastline protection against SLR. The soil accretion of these ecosystems has never been assessed in hot desert climate regions, where water runoff is negligible. However, tropical marine ecosystems are areas of intense calcification that may constitute an important source of sediment supporting seabed elevation, compensating for the lack of terrestrial inputs. We estimated the long-term (C-centennial) and short-term (Pb-20th century) soil accretion rates (SARs) and inorganic carbon (C) burial in coastal vegetated ecosystems of the Saudi coasts of the central Red Sea and the Arabian Gulf. Short-term SARs (±SE) in mangroves of the Red Sea (0.27 ± 0.22 cm/year) were twofold the SLR for that region since 1925 (0.13 cm/year). In the Arabian Gulf, only mangrove forest SAR is equivalent to local SLR estimates for the period 1979-2007 (0.21 ± 0.09 compared to 0.22 ± 0.05 cm/year, respectively). Long-term SARs are comparable or higher than the global estimates of SLR for the late Holocene (0.01 cm/year). In all habitats of the Red Sea and Arabian Gulf, SARs are supported by high carbonate accretion rates, comprising 40% to 60% of the soil volume. Further studies on the role of carbonates in coastal vegetated ecosystems are required to understand their role in adaptation to SLR.

Accumulation of Carbonates Contributes to Coastal Vegetated Ecosystems Keeping Pace With Sea Level Rise in an Arid Region (Arabian Peninsula)

KAUST Repository

Saderne, Vincent

2018-04-12

Anthropogenic sea level rise (SLR) presents one of the greatest risks to human lives and infrastructures. Coastal vegetated ecosystems, that is, tidal marshes, seagrass meadows, and mangrove forests, elevate the seabed through soil accretion, providing a natural coastline protection against SLR. The soil accretion of these ecosystems has never been assessed in hot desert climate regions, where water runoff is negligible. However, tropical marine ecosystems are areas of intense calcification that may constitute an important source of sediment supporting seabed elevation, compensating for the lack of terrestrial inputs. We estimated the long-term (C-centennial) and short-term (Pb-20th century) soil accretion rates (SARs) and inorganic carbon (C) burial in coastal vegetated ecosystems of the Saudi coasts of the central Red Sea and the Arabian Gulf. Short-term SARs (±SE) in mangroves of the Red Sea (0.27 ± 0.22 cm/year) were twofold the SLR for that region since 1925 (0.13 cm/year). In the Arabian Gulf, only mangrove forest SAR is equivalent to local SLR estimates for the period 1979-2007 (0.21 ± 0.09 compared to 0.22 ± 0.05 cm/year, respectively). Long-term SARs are comparable or higher than the global estimates of SLR for the late Holocene (0.01 cm/year). In all habitats of the Red Sea and Arabian Gulf, SARs are supported by high carbonate accretion rates, comprising 40% to 60% of the soil volume. Further studies on the role of carbonates in coastal vegetated ecosystems are required to understand their role in adaptation to SLR.

The importance of dissimilatory nitrate reduction to ammonium (DNRA) in the nitrogen cycle of coastal ecosystems

DEFF Research Database (Denmark)

Giblin, Anne E.; Tobias, Craig R.; Song, Bongkeun

2013-01-01

Until recently, it was believed that biological assimilation and gaseous nitrogen (N) loss through denitrification were the two major fates of nitrate entering or produced within most coastal ecosystems. Denitrification is often viewed as an important ecosystem service that removes reactive N from...... the ecosystem. However, there is a competing nitrate reduction process, dissimilatory nitrate reduction to ammonium (DNRA), that conserves N within the ecosystem. The recent application of nitrogen stable isotopes as tracers has generated growing evidence that DNRA is a major nitrogen pathway that cannot...... of denitrification and DNRA, and how the balance changes with increased nitrogen loading, is of critical importance for predicting eutrophication trajectories. Recent improvements in methods for assessing rates of DNRA have helped refine our understanding of the rates and controls of this process, but accurate...

Land-margin ecosystem hydrologic data for the coastal Everglades, Florida, water years 1996-2012

Science.gov (United States)

Anderson, Gordon H.; Smith, Thomas J.; Balentine, Karen M.

2014-01-01

Mangrove forests and salt marshes dominate the landscape of the coastal Everglades (Odum and McIvor, 1990). However, the ecological effects from potential sea-level rise and increased water flows from planned freshwater Everglades restoration on these coastal systems are poorly understood. The National Park Service (NPS) proposed the South Florida Global Climate Change Project (SOFL-GCC) in 1990 to evaluate climate change and the effect from rising sea levels on the coastal Everglades, particularly at the marsh/mangrove interface or ecotone (Soukup and others, 1990). A primary objective of SOFL-GCC project was to monitor and synthesize the hydrodynamics of the coastal Everglades from the upstream freshwater marsh to the downstream estuary mangrove. Two related hypotheses were set forward (Nuttle and Cosby, 1993): 1. There exists hydrologic conditions (tide, local rainfall, and upstream water deliveries), which characterize the location of the marsh/mangrove ecotone along the marine and terrestrial hydrologic gradient; and 2. The marsh/mangrove ecotone is sensitive to fluctuations in sea level and freshwater inflow from inland areas. Hydrologic monitoring of the SOFL-GCC network began in 1995 after startup delays from Hurricane Andrew (August 1992) and organizational transfers from the NPS to the National Biological Survey (October 1993) and the merger with the U.S. Geological Survey (USGS) Biological Research Division in 1996 (Smith, 2004). As the SOFL-GCC project progressed, concern by environmental scientists and land managers over how the diversion of water from Everglades National Park would affect the restoration of the greater Everglades ecosystem. Everglades restoration scenarios were based on hydrodynamic models, none of which included the coastal zone (Fennema and others, 1994). Modeling efforts were expanded to include the Everglades coastal zone (Schaffranek and others, 2001) with SOFL-GCC hydrologic data assisting the ecological modeling needs. In 2002

The circulation dynamics associated with a northern Benguela upwelling filament during October 2010

Science.gov (United States)

Muller, Annethea A.; Mohrholz, Volker; Schmidt, Martin

2013-07-01

Upwelling filaments, a common feature in all the major upwelling systems, are also regularly observed in the Benguela upwelling system and are thought to provide an effective mechanism for the exchange of matter between the shelf and the open ocean. The mesoscale dynamics of a northern Benguela upwelling filament located at approximately 18.5°S were examined and the associated transport was quantified. The development of the filament was tracked using optimal interpolated SST satellite data and two transects were consequently sampled across the feature using a towed undulating CTD (ScanFish). Additional hydrographic, nutrient and biological parameters were investigated at several stations along each transect. Following 7 days of strong upwelling favorable winds, sampling coincided with a period of relative wind relaxation and the filament was presumably in a decaying state. The basic mesoscale structure of the investigated filament corresponded well to what had previously been described for filaments from other eastern boundary current systems. The cross-shore transport associated with the filament was found to be significantly greater than the integrated Ekman transport in the region. With the combination of the high resolution dataset and a MOM-4 ecosystem model the complex mesoscale flow field associated with the feature could be observed and the counterbalancing onshore transport, associated with subsurface dipole eddies, was revealed within the filament. The results further suggest that an interaction between the offshore bending of flow at the Angola-Benguela Front (ABF), the detachment of the strong poleward flow from the coast as the thermal front meanders and the observed dipole eddies may be driving filament occurrence in the region off Cape Frio.

Convergent tectonics and coastal upwelling: a history of the Peru continental margin ( Pacific).

Science.gov (United States)

von Huene, Roland E.; Suess, E.; Emeis, K.C.

1987-01-01

Late in 1986, scientists on the ODP drillship JOIDES Resolution confirmed that the upper slope of the Peruvian margin consists of continental crust whereas the lower slope comprises an accretionary complex. An intricate history of horizontal and vertical movements can be detected, and the locations of ancient centers of upwelling appear to have varied, partly due to tectonic movements of the margin. In this review of Leg 112, the 3 scientific leaders on this cruise discuss their results. -from Journal Editor

Natural ocean acidification at Papagayo upwelling system (north Pacific Costa Rica: implications for reef development

Directory of Open Access Journals (Sweden)

C. Sánchez-Noguera

2018-04-01

Full Text Available Numerous experiments have shown that ocean acidification impedes coral calcification, but knowledge about in situ reef ecosystem response to ocean acidification is still scarce. Bahía Culebra, situated at the northern Pacific coast of Costa Rica, is a location naturally exposed to acidic conditions due to the Papagayo seasonal upwelling. We measured pH and pCO2 in situ during two non-upwelling seasons (June 2012, May–June 2013, with a high temporal resolution of every 15 and 30 min, respectively, using two Submersible Autonomous Moored Instruments (SAMI-pH, SAMI-CO2. These results were compared with published data from the 2009 upwelling season. Findings revealed that the carbonate system in Bahía Culebra shows a high temporal variability. Incoming offshore waters drive intra- and interseasonal changes. Lowest pH (7.8 and highest pCO2 (658.3 µatm values measured during a cold-water intrusion event in the non-upwelling season were similar to those minimum values reported from upwelling season (pH  =  7.8, pCO2  =  643.5 µatm, unveiling that natural acidification also occurs sporadically in the non-upwelling season. This affects the interaction of photosynthesis, respiration, calcification and carbonate dissolution and the resulting diel cycle of pH and pCO2 in the reefs of Bahía Culebra. During the non-upwelling season, the aragonite saturation state (Ωa rises to values of  >  3.3 and during the upwelling season falls below 2.5. The Ωa threshold values for coral growth were derived from the correlation between measured Ωa and coral linear extension rates which were obtained from the literature and suggest that future ocean acidification will threaten the continued growth of reefs in Bahía Culebra. These data contribute to building a better understanding of the carbonate system dynamics and coral reefs' key response (e.g., coral growth to natural low-pH conditions, in upwelling areas in the eastern tropical

The use of circulation weather types to predict upwelling activity along the Western Iberian Peninsula coast

Science.gov (United States)

Ramos, Alexandre M.; Cordeiro Pires, Ana; Sousa, Pedro M.; Trigo, Ricardo M.

2013-04-01

Coastal upwelling is a phenomenon that occurs in most western oceanic coasts due to the presence of mid-latitude high-pressure systems that generate equatorward winds along the coast and consequent offshore displacement of surface waters that in turn cause deeper, colder, nutrient-rich waters to arise. In western Iberian Peninsula (IP) the high-pressure system associated to northerly winds occurs mainly during spring and summer. Upwelling systems are economically relevant, being the most productive regions of the world ocean and crucial for fisheries. In this work, we evaluate the intra- and inter-annual variability of the Upwelling Index (UI) off the western coast of the IP considering four locations at various latitudes: Rias Baixas, Aveiro, Figueira da Foz and Cabo da Roca. In addition, the relationship between the variability of the occurrence of several circulation weather types (Ramos et al., 2011) and the UI variability along this coast was assessed in detail, allowing to discriminate which types are frequently associated with strong and weak upwelling activity. It is shown that upwelling activity is mostly driven by wind flow from the northern quadrant, for which the obtained correlation coefficients (for the N and NE types) are higher than 0.5 for the four considered test locations. Taking into account these significant relationships, we then developed statistical multi-linear regression models to hindcast upwelling series (April to September) at the four referred locations, using monthly frequencies of circulation weather types as predictors. Modelled monthly series reproduce quite accurately observational data, with correlation coefficients above 0.7 for all locations, and relatively small absolute errors. Ramos AM, Ramos R, Sousa P, Trigo RM, Janeira M, Prior V (2011) Cloud to ground lightning activity over Portugal and its association with Circulation Weather Types. Atmospheric Research 101:84-101. doi: 10.1016/j.atmosres.2011.01

Application of the Benthic Ecosystem Quality Index 2 to benthos in Dutch transitional and coastal waters

NARCIS (Netherlands)

Van Loon, W.M.G.M.; Boon, A.R.; Gittenberger, A.; Walvoort, D.J.J.; Lavaleye, M.S.S.; Duineveld, G.C.A.; Verschoor, A.J.

2015-01-01

The Benthic Ecosystem Quality Index 2 (BEQI2) is the Dutch multi-metric index (MMI) for assessing the status and trend of benthic invertebrates in transitional and coastal waters for the Water Framework Directive (WFD). It contains the same indicators, i.e. species richness, Shannon index and AMBI,

Application of the Benthic Ecosystem Quality Index 2 to benthos in Dutch transitional and coastal waters

NARCIS (Netherlands)

Loon, van W.M.G.M.; Boon, A.R.; Gittenberger, A.; Walvoort, D.J.J.; Lavaleye, M.; Duineveld, G.C.A.; Verschoor, A.J.

2015-01-01

The Benthic Ecosystem Quality Index 2 (BEQI2) is the Dutch multi-metric index (MMI) for assessing the status and trend of benthic invertebrates in transitional and coastal waters for the Water Framework Directive (WFD). It contains the same indicators, i.e. species richness, Shannon index and

Hydrodynamic control of microphytoplankton bloom in a coastal sea

Indian Academy of Sciences (India)

K Narasimha Murty

2017-08-31

Aug 31, 2017 ... surface water to depths in regions where there is no barrier layer at the ... ent availability (and light) alone does not give place to blooms in the ...... ics in a coastal upwelling system off southwestern Africa;. Deep Sea Res.

Anthropogenic nutrient sources rival natural sources on small scales in the coastal waters of the Southern California Bight

KAUST Repository

Howard, Meredith D. A.; Sutula, Martha; Caron, David A.; Chao, Yi; Farrara, John D.; Frenzel, Hartmut; Jones, Burton; Robertson, George; McLaughlin, Karen; Sengupta, Ashmita

2014-01-01

Anthropogenic nutrients have been shown to provide significant sources of nitrogen (N) that have been linked to increased primary production and harmful algal blooms worldwide. There is a general perception that in upwelling regions, the flux of anthropogenic nutrient inputs is small relative to upwelling flux, and therefore anthropogenic inputs have relatively little effect on the productivity of coastal waters. To test the hypothesis that natural sources (e.g., upwelling) greatly exceed anthropogenic nutrient sources to the Southern California Bight (SCB), this study compared the source contributions of N from four major nutrient sources: (1) upwelling, (2) treated wastewater effluent discharged to ocean outfalls, (3) riverine runoff, and (4) atmospheric deposition. This comparison was made using large regional data sets combined with modeling on both regional and local scales. At the regional bight-wide spatial scale, upwelling was the largest source of N by an order of magnitude to effluent and two orders of magnitude to riverine runoff. However, at smaller spatial scales, more relevant to algal bloom development, natural and anthropogenic contributions were equivalent. In particular, wastewater effluent and upwelling contributed the same quantity of N in several subregions of the SCB. These findings contradict the currently held perception that in upwelling-dominated regions anthropogenic nutrient inputs are negligible, and suggest that anthropogenic nutrients, mainly wastewater effluent, can provide a significant source of nitrogen for nearshore productivity in Southern California coastal waters.

Anthropogenic nutrient sources rival natural sources on small scales in the coastal waters of the Southern California Bight

KAUST Repository

Howard, Meredith D. A.

2014-01-26

Anthropogenic nutrients have been shown to provide significant sources of nitrogen (N) that have been linked to increased primary production and harmful algal blooms worldwide. There is a general perception that in upwelling regions, the flux of anthropogenic nutrient inputs is small relative to upwelling flux, and therefore anthropogenic inputs have relatively little effect on the productivity of coastal waters. To test the hypothesis that natural sources (e.g., upwelling) greatly exceed anthropogenic nutrient sources to the Southern California Bight (SCB), this study compared the source contributions of N from four major nutrient sources: (1) upwelling, (2) treated wastewater effluent discharged to ocean outfalls, (3) riverine runoff, and (4) atmospheric deposition. This comparison was made using large regional data sets combined with modeling on both regional and local scales. At the regional bight-wide spatial scale, upwelling was the largest source of N by an order of magnitude to effluent and two orders of magnitude to riverine runoff. However, at smaller spatial scales, more relevant to algal bloom development, natural and anthropogenic contributions were equivalent. In particular, wastewater effluent and upwelling contributed the same quantity of N in several subregions of the SCB. These findings contradict the currently held perception that in upwelling-dominated regions anthropogenic nutrient inputs are negligible, and suggest that anthropogenic nutrients, mainly wastewater effluent, can provide a significant source of nitrogen for nearshore productivity in Southern California coastal waters.

Benthic macroinvertebrates as ecological indicators for estuarine and coastal ecosystems : assessment and intercalibration

OpenAIRE

Teixeira, Heliana Lilita Gonçalves

2010-01-01

Tese de doutoramento em Biologia (Ecologia) apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra The aim of the research work presented in this thesis is to be a contribution to the field of ecological assessment in coastal and transitional ecosystems. The main goals were: a) to present a method for the assessment of the ecological status of benthic macroinvertebrate communities in Portuguese transitional waters that would meet the requirements of the Eur...

Exposure of coastal ecosystems to river plume spreading across a near-equatorial continental shelf

Science.gov (United States)

Tarya, A.; Hoitink, A. J. F.; Vegt, M. Van der; van Katwijk, M. M.; Hoeksema, B. W.; Bouma, T. J.; Lamers, L. P. M.; Christianen, M. J. A.

2018-02-01

The Berau Continental Shelf (BCS) in East Kalimantan, Indonesia, harbours various tropical marine ecosystems, including mangroves, seagrass meadows and coral reefs. These ecosystem are located partly within reach of the Berau River plume, which may affect ecosystem health through exposure to land-derived sediments, nutrients and pollutants carried by the plume. This study aims (1) to assess the exposure risk of the BCS coastal ecosystems to river plume water, measured as exposure time to three different salinity levels, (2) to identify the relationships between these salinity levels and the abundance and diversity of coral and seagrass ecosystems, and (3) to determine a suitable indicator for the impacts of salinity on coral reef and seagrass health. We analysed hydrodynamic models, classified salinity levels, and quantified the correlations between the salinity model parameters and ecological metrics for the BCS systems. An Empirical Orthogonal Functions (EOF) analysis revealed three modes of river plume dispersal patterns, which strongly reflect monsoon seasonality. The first mode, explaining 39% of the variability, was associated with the southward movement of the plume due to northerly winds, while the second and third modes (explaining 29% and 26% of the variability, respectively) were associated with the northeastward migration of the plume related to southwesterly and southerly winds. Exposure to low salinity showed higher correlations with biological indicators than mean salinity, indicating that low salinity is a more suitable indicator for coastal ecosystem health. Significant correlations (R2) were found between exposure time to low salinity (days with salinity values below 25 PSU) with coral cover, coral species richness, seagrass cover, the number of seagrass species, seagrass leaf phosphorus, nitrogen, C:N ratio and iron content. By comparing the correlation coefficients and the slopes of the regression lines, our study suggests that coral reefs are

A COMPARATIVE ANALYSIS OF SPECIES COMPOSITION OF GROUND BEETLES OF COASTAL AND ISLAND ECOSYSTEMS OF THE WESTERN CASPIAN

Directory of Open Access Journals (Sweden)

G. M. Abdurakhmanov

2011-01-01

Full Text Available For the first time studied the species composition of ground beetles of coastal and island ecosystems of the Western Caspian. The article provides a comparative analysis of species composition of ground beetles and adjacent areas.

Developments in Coastal Ocean Modeling

Science.gov (United States)

Allen, J. S.

2001-12-01

Capabilities in modeling continental shelf flow fields have improved markedly in the last several years. Progress is being made toward the long term scientific goal of utilizing numerical circulation models to interpolate, or extrapolate, necessarily limited field measurements to provide additional full-field information describing the behavior of, and providing dynamical rationalizations for, complex observed coastal flow. The improvement in modeling capabilities has been due to several factors including an increase in computer power and, importantly, an increase in experience of modelers in formulating relevant numerical experiments and in analyzing model results. We demonstrate present modeling capabilities and limitations by discussion of results from recent studies of shelf circulation off Oregon and northern California (joint work with Newberger, Gan, Oke, Pullen, and Wijesekera). Strong interactions between wind-forced coastal currents and continental shelf topography characterize the flow regimes in these cases. Favorable comparisons of model and measured alongshore currents and other variables provide confidence in the model-produced fields. The dependence of the mesoscale circulation, including upwelling and downwelling fronts and flow instabilities, on the submodel used to parameterize the effects of small scale turbulence, is discussed. Analyses of model results to provide explanations for the observed, but previously unexplained, alongshore variability in the intensity of coastal upwelling, which typically results in colder surface water south of capes, and the observed development in some locations of northward currents near the coast in response to the relaxation of southward winds, are presented.

Airborne Mission Concept for Coastal Ocean Color and Ecosystems Research

Science.gov (United States)

Guild, Liane S.; Hooker, Stanford B.; Morrow, John H.; Kudela, Raphael M.; Palacios, Sherry L.; Torres Perez, Juan L.; Hayashi, Kendra; Dunagan, Stephen E.

2016-01-01

NASA airborne missions in 2011 and 2013 over Monterey Bay, CA, demonstrated novel above- and in-water calibration and validation measurements supporting a combined airborne sensor approach (imaging spectrometer, microradiometers, and a sun photometer). The resultant airborne data characterize contemporaneous coastal atmospheric and aquatic properties plus sea-truth observations from state-of-the-art instrument systems spanning a next-generation spectral domain (320-875 nm). This airborne instrument suite for calibration, validation, and research flew at the lowest safe altitude (ca. 100 ft or 30 m) as well as higher altitudes (e.g., 6,000 ft or 1,800 m) above the sea surface covering a larger area in a single synoptic sortie than ship-based measurements at a few stations during the same sampling period. Data collection of coincident atmospheric and aquatic properties near the sea surface and at altitude allows the input of relevant variables into atmospheric correction schemes to improve the output of corrected imaging spectrometer data. Specific channels support legacy and next-generation satellite capabilities, and flights are planned to within 30 min of satellite overpass. This concept supports calibration and validation activities of ocean color phenomena (e.g., river plumes, algal blooms) and studies of water quality and coastal ecosystems. The 2011 COAST mission flew at 100 and 6,000 ft on a Twin Otter platform with flight plans accommodating the competing requirements of the sensor suite, which included the Coastal-Airborne In-situ Radiometers (C-AIR) for the first time. C-AIR (Biospherical Instruments Inc.) also flew in the 2013 OCEANIA mission at 100 and 1,000 ft on the Twin Otter below the California airborne simulation of the proposed NASA HyspIRI satellite system comprised of an imaging spectrometer and thermal infrared multispectral imager on the ER-2 at 65,000 ft (20,000 m). For both missions, the Compact-Optical Profiling System (Biospherical

Modeled Sea Level Rise Impacts on Coastal Ecosystems at Six Major Estuaries on Florida's Gulf Coast: Implications for Adaptation Planning.

Science.gov (United States)

Geselbracht, Laura L; Freeman, Kathleen; Birch, Anne P; Brenner, Jorge; Gordon, Doria R

2015-01-01

The Sea Level Affecting Marshes Model (SLAMM) was applied at six major estuaries along Florida's Gulf Coast (Pensacola Bay, St. Andrews/Choctawhatchee Bays, Apalachicola Bay, Southern Big Bend, Tampa Bay and Charlotte Harbor) to provide quantitative and spatial information on how coastal ecosystems may change with sea level rise (SLR) and to identify how this information can be used to inform adaption planning. High resolution LiDAR-derived elevation data was utilized under three SLR scenarios: 0.7 m, 1 m and 2 m through the year 2100 and uncertainty analyses were conducted on selected input parameters at three sites. Results indicate that the extent, spatial orientation and relative composition of coastal ecosystems at the study areas may substantially change with SLR. Under the 1 m SLR scenario, total predicted impacts for all study areas indicate that coastal forest (-69,308 ha; -18%), undeveloped dry land (-28,444 ha; -2%) and tidal flat (-25,556 ha; -47%) will likely face the greatest loss in cover by the year 2100. The largest potential gains in cover were predicted for saltmarsh (+32,922 ha; +88%), transitional saltmarsh (+23,645 ha; na) and mangrove forest (+12,583 ha; +40%). The Charlotte Harbor and Tampa Bay study areas were predicted to experience the greatest net loss in coastal wetlands The uncertainty analyses revealed low to moderate changes in results when some numerical SLAMM input parameters were varied highlighting the value of collecting long-term sedimentation, accretion and erosion data to improve SLAMM precision. The changes predicted by SLAMM will affect exposure of adjacent human communities to coastal hazards and ecosystem functions potentially resulting in impacts to property values, infrastructure investment and insurance rates. The results and process presented here can be used as a guide for communities vulnerable to SLR to identify and prioritize adaptation strategies that slow and/or accommodate the changes underway.

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

Contrasting Patterns of Phytoplankton Assemblages in Two Coastal Ecosystems in Relation to Environmental Factors (Corsica, NW Mediterranean Sea

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Marie Garrido

2014-04-01

Full Text Available Corsica Island is a sub-basin of the Northwestern Mediterranean Sea, with hydrological features typical of both oligotrophic systems and eutrophic coastal zones. Phytoplankton assemblages in two coastal ecosystems of Corsica (the deep Bay of Calvi and the shallow littoral of Bastia show contrasting patterns over a one-year cycle. In order to determine what drives these variations, seasonal changes in littoral phytoplankton are considered together with environmental parameters. Our methodology combined a survey of the physico-chemical structure of the subsurface water with a characterization of the phytoplankton community structure. Sampling provided a detailed record of the seasonal changes and successions that occur in these two areas. Results showed that the two sampled stations presented different phytoplankton abundance and distribution patterns, notably during the winter–spring bloom period. Successions in pico-, nano-, and microphytoplankton communities appeared mainly driven by differences in the ability to acquire nutrients, and in community-specific growth rates. Phytoplankton structure and dynamics are discussed in relation to available data on the Northwestern Mediterranean Sea. These results confirm that integrated monitoring of coastal areas is a requisite for gaining a proper understanding of marine ecosystems.

Ecosystem resilience and threshold response in the Galápagos coastal zone.

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Alistair W R Seddon

Full Text Available BACKGROUND: The Intergovernmental Panel on Climate Change (IPCC provides a conservative estimate on rates of sea-level rise of 3.8 mm yr(-1 at the end of the 21(st century, which may have a detrimental effect on ecologically important mangrove ecosystems. Understanding factors influencing the long-term resilience of these communities is critical but poorly understood. We investigate ecological resilience in a coastal mangrove community from the Galápagos Islands over the last 2700 years using three research questions: What are the 'fast and slow' processes operating in the coastal zone? Is there evidence for a threshold response? How can the past inform us about the resilience of the modern system? METHODOLOGY/PRINCIPAL FINDINGS: Palaeoecological methods (AMS radiocarbon dating, stable carbon isotopes (δ(13C were used to reconstruct sedimentation rates and ecological change over the past 2,700 years at Diablas lagoon, Isabela, Galápagos. Bulk geochemical analysis was also used to determine local environmental changes, and salinity was reconstructed using a diatom transfer function. Changes in relative sea level (RSL were estimated using a glacio-isostatic adjustment model. Non-linear behaviour was observed in the Diablas mangrove ecosystem as it responded to increased salinities following exposure to tidal inundations. A negative feedback was observed which enabled the mangrove canopy to accrete vertically, but disturbances may have opened up the canopy and contributed to an erosion of resilience over time. A combination of drier climatic conditions and a slight fall in RSL then resulted in a threshold response, from a mangrove community to a microbial mat. CONCLUSIONS/SIGNIFICANCE: Palaeoecological records can provide important information on the nature of non-linear behaviour by identifying thresholds within ecological systems, and in outlining responses to 'fast' and 'slow' environmental change between alternative stable states. This study

Wind-driven upwelling effects on cephalopod paralarvae: Octopus vulgaris and Loliginidae off the Galician coast (NE Atlantic)

Science.gov (United States)

Otero, Jaime; Álvarez-Salgado, X. Antón; González, Ángel F.; Souto, Carlos; Gilcoto, Miguel; Guerra, Ángel

2016-02-01

Circulation patterns of coastal upwelling areas may have central consequences for the abundance and cross-shelf transport of the larval stages of many species. Previous studies have provided evidences that larvae distribution results from a combination of subtidal circulation, species-specific behaviour and larval sources. However, most of these works were conducted on organisms characterised by small-sized and abundant early life phases. Here, we studied the influence of the hydrography and circulation of the Ría de Vigo and adjacent shelf (NW Iberian upwelling system) on the paralarval abundance of two contrasting cephalopods, the benthic common octopus (Octopus vulgaris) and the pelagic squids (Loliginidae). We sampled repeatedly a cross-shore transect during the years 2003-2005 and used zero inflated models to accommodate the scarcity and patchy distribution of cephalopod paralarvae. The probability of catching early stages of both cephalopods was higher at night. Octopus paralarvae were more abundant in the surface layer at night whereas loliginids preferred the bottom layer regardless of the sampling time. Abundance of both cephalopods increased when shelf currents flowed polewards, water temperature was high and water column stability was low. The probability of observing an excess of zero catches decreased during the year for octopus and at high current speed for loliginids. In addition, the circulation pattern conditioned the body size distribution of both paralarvae; while the average size of the captured octopuses increased (decreased) with poleward currents at daylight (nighttime), squids were smaller with poleward currents regardless of the sampling time. These results contribute to the understanding of the effects that the hydrography and subtidal circulation of a coastal upwelling have on the fate of cephalopod early life stages.

Southern African Coastal vulnerability assessment

CSIR Research Space (South Africa)

Rautenbach, C

2015-10-01

Full Text Available or business. The CSIR coastal systems group uses specialist skills in coastal engineering, geographic engineering systems and numerical modelling to assess and map vulnerable coastal ecosystems to develop specific adaptation measures and coastal protection...

Stable nitrogen isotopes in coastal macroalgae: Geographic and anthropogenic variability

International Nuclear Information System (INIS)

Viana, Inés G.; Bode, Antonio

2013-01-01

Growing human population adds to the natural nitrogen loads to coastal waters. Both anthropogenic and natural nitrogen is readily incorporated in new biomass, and these different nitrogen sources may be traced by the measurement of the ratio of stable nitrogen isotopes (δ 15 N). In this study δ 15 N was determined in two species of macroalgae (Ascophyllum nodosum and Fucus vesiculosus), and in nitrate and ammonium to determine the relative importance of anthropogenic versus natural sources of nitrogen along the coast of NW Spain. Both algal species and nitrogen sources showed similar isotopic enrichment for a given site, but algal δ 15 N was not related to either inorganic nitrogen concentrations or δ 15 N in the water samples. The latter suggests that inorganic nitrogen inputs are variable and do not always leave an isotopic trace in macroalgae. However, a significant linear decrease in macroalgal δ 15 N along the coast is consistent with the differential effect of upwelling. Besides this geographic variability, the influence of anthropogenic nitrogen sources is evidenced by higher δ 15 N in macroalgae from rias and estuaries compared to those from open coastal areas and in areas with more than 15 × 10 3 inhabitants in the watershed. These results indicate that, in contrast with other studies, macroalgal δ 15 N is not simply related to either inorganic nitrogen concentrations or human population size but depends on other factors as the upwelling or the efficiency of local waste treatment systems. - Highlights: ► Anthropogenic versus upwelling nitrogen effect on macroalgal δ 15 N was studied. ► The influence of populations and upwelling has not been made before on macroalgal δ 15 N. ► Natural variability has not been taken into account in most biomonitoring studies. ► Upwelling explains most of the variability in δ 15 N in macroalgae

Variabilidad mensual de la velocidad de surgencia y clorofila a en la región del Panama Bight (Monthly rate variation upwelling and chlorophyll a in the region of Panama Bight

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Nancy Villegas

2016-09-01

Full Text Available Las zonas de surgencia y la presencia de clorofila a en la región del Panamá Bight (golfo de Panamá fueron comparadas en una escala mensual. Las variables utilizadas fueron la velocidad vertical de surgencia estimada mediante el software EVA. V.2.0 y la concentración de clorofila a obtenida de imágenes satelitales SeaWifs. El estudio fue realizado para el área costera entre 6° 30’ y 2° N y en los tres principales focos de ascenso de agua, el primero ubicado entre 83-84° W y 1° 30’-2° 30’ N, el segundo entre 81-82° W y 1° 30’-2° 30’ N, y el tercero entre 82-83° W y 2° 30’-3° 30’ N. Los resultados muestran la asociación directa entre la concentración de clorofila a y la surgencia durante todo el año. El estudio también resalta que el desplazamiento de la zona de convergencia intertropical ZCIT determina la variabilidad estacional del proceso de ascenso, atenuándolo cuando pasa sobre el área de estudio y reforzándolo mientras se aleja. El análisis de correlación entre las variables bajo estudio dio como resultado coeficientes estadísticamente significativos entre 0.5 y 0.9 en los tres focos principales y valores no significativos en la zona costera. (Abstract. The influence of the migration of the ITCZ on the climatic variability of the upwelling vertical velocity (Vz and the spatial-temporal behavior of upwelling spots over the CPO was determined. This influence was corroborated by the presence of chlorophyll a in the upwelling zones. Vz values were calculated with EVA . V.2.0 software. The chlorophyll a content was extracted from satellite images for 1997-2000. A comparison between the upwelling zones distribution, the migration of ITCZ and chlorophyll a was made. This comparison was based on the correlation between variables of three upwelling focuses and a coastal upwelling. The first focus was located between 83-84° W and 1° 30’-2° 30’ N, the second one between 81-82° W and 1° 30’- 2° 30�

Introduction to the special issue on “Understanding and predicting change in the coastal ecosystems of the northern Gulf of Mexico”

Science.gov (United States)

Brock, John C.; Barras, John A.; Williams, S. Jeffress

2013-01-01

The coastal region of the northern Gulf of Mexico owes its current landscape structure to an array of tectonic, erosional and depositional, climatic, geochemical, hydrological, ecological, and human processes that have resulted in some of the world's most complex, dynamic, productive, and threatened ecosystems. Catastrophic hurricane landfalls, ongoing subsidence and erosion exacerbated by sea-level rise, disintegration of barrier island chains, and high rates of wetland loss have called attention to the vulnerability of northern Gulf coast ecosystems, habitats, built infrastructure, and economy to natural and anthropogenic threats. The devastating hurricanes of 2005 (Katrina and Rita) motivated the U.S. Geological Survey Coastal and Marine Geology Program and partnering researchers to pursue studies aimed at understanding and predicting landscape change and the associated storm hazard vulnerability of northern Gulf coast region ecosystems and human communities. Attaining this science goal requires increased knowledge of landscape evolution on geologic, historical, and human time scales, and analysis of the implications of such changes in the natural and built components of the landscape for hurricane impact susceptibility. This Special Issue of the Journal of Coastal Research communicates northern Gulf of Mexico research results that (1) improve knowledge of prior climates and depositional environments, (2) assess broad regional ecosystem structure and change over Holocene to human time scales, (3) undertake process studies and change analyses of dynamic landscape components, and (4) integrate framework, climate, variable time and spatial scale mapping, monitoring, and discipline-specific process investigations within interdisciplinary studies.

Uncertainty Analysis of Phytoplankton Dynamics in Coastal Waters

NARCIS (Netherlands)

Niu, L.

2015-01-01

There is an increasing concern about the interactions between phytoplankton and coastal ecosystems, especially on the negative effects from coastal eutrophication and phytoplankton blooms. As the key indicator of the coastal ecosystem, phytoplankton plays an important role in the whole impact-effect

Development of Phaeocystis globosa blooms in the upwelling waters of the South Central coast of Viet Nam

Science.gov (United States)

Hai, Doan-Nhu; Lam, Nguyen-Ngoc; Dippner, Joachim W.

2010-11-01

Blooms of haptophyte algae in the south central coastal waters of Viet Nam often occur in association with upwelling phenomenon during the southwest (SW) monsoon. Depending on the magnitude of the blooms, damage to aquaculture farms may occur. Based on two years of data on biology, oceanography, and marine chemistry, the present study suggests a conceptual model of the growth of the haptophyte Phaeocystis globosa. At the beginning of the bloom, low temperature and abundant nutrient supply, especially nitrate from rain and upwelling, favour bloom development. Diatoms utilize available nitrate and phosphate; subsequently, higher ammonium concentration allows P. globosa to grow faster than the diatoms. At the end of the Phaeocystis bloom, free cells may become available as food for a heterotrophic dinoflagellate species, Noctiluca scintillans. During and after the phytoplankton bloom, remineralization by bacteria reduces dissolved oxygen to a very low concentration at depth, and favors growth of nitrate-reducing bacteria.A Lagrangian Harmful Algal Bloom (HAB) model, driven by a circulation model of the area, realistically simulates the transport of microalgae in surface waters during strong and weak SW monsoon periods, suggesting that it may be a good tool for early warning of HABs in Vietnamese coastal waters.

Risks for marine coastal ecosystems from anthropogenic loading in the Leningrad NPP environs

International Nuclear Information System (INIS)

Zimina, L.; Zimin, V.; Shchukina, T.; Pomiluiko, G.; Ryabova, V.

1998-01-01

Data on conditions and variations in phytoplankton, zooplankton and fish communities, chlorophyll 'a' and hydrochemical parameters in the coastal waters of Koporskaya Bay (cooling water body of the Leningrad NPP) were analyzed. The most significant anthropogenic factors issued from the Leningrad nuclear power plant activity are of non-radioactive character, as it was recognized during long-time (20 years) ecological monitoring. Main factors influenced ecosystem of the NPP cooling water body are thermal water discharge and nutrient outflows from the bay catchment area. (authors)

Primary producers may ameliorate impacts of daytime CO2 addition in a coastal marine ecosystem.

Science.gov (United States)

Bracken, Matthew E S; Silbiger, Nyssa J; Bernatchez, Genevieve; Sorte, Cascade J B

2018-01-01

Predicting the impacts of ocean acidification in coastal habitats is complicated by bio-physical feedbacks between organisms and carbonate chemistry. Daily changes in pH and other carbonate parameters in coastal ecosystems, associated with processes such as photosynthesis and respiration, often greatly exceed global mean predicted changes over the next century. We assessed the strength of these feedbacks under projected elevated CO 2 levels by conducting a field experiment in 10 macrophyte-dominated tide pools on the coast of California, USA. We evaluated changes in carbonate parameters over time and found that under ambient conditions, daytime changes in pH, p CO 2 , net ecosystem calcification ( NEC ), and O 2 concentrations were strongly related to rates of net community production ( NCP ). CO 2 was added to pools during daytime low tides, which should have reduced pH and enhanced p CO 2 . However, photosynthesis rapidly reduced p CO 2 and increased pH, so effects of CO 2 addition were not apparent unless we accounted for seaweed and surfgrass abundances. In the absence of macrophytes, CO 2 addition caused pH to decline by ∼0.6 units and p CO 2 to increase by ∼487 µatm over 6 hr during the daytime low tide. As macrophyte abundances increased, the impacts of CO 2 addition declined because more CO 2 was absorbed due to photosynthesis. Effects of CO 2 addition were, therefore, modified by feedbacks between NCP , pH, p CO 2 , and NEC . Our results underscore the potential importance of coastal macrophytes in ameliorating impacts of ocean acidification.

Testing compound-specific δ13C of amino acids in mussels as a new approach to determine the average 13C values of primary production in littoral ecosystems

Science.gov (United States)

Vokhshoori, N. L.; Larsen, T.; McCarthy, M.

2012-12-01

Compound-specific isotope analysis of amino acids (CSI-AA) is a technique used to decouple trophic enrichment patterns from source changes at the base of the food web. With this new emerging tool, it is possible to precisely determine both trophic position and δ15N or δ13C source values in higher feeding organisms. While most work to date has focused on nitrogen (N) isotopic values, early work has suggested that δ13C CSI-AA has great potential as a new tracer both to a record δ13C values of primary production (unaltered by trophic transfers), and also to "fingerprint" specific carbon source organisms. Since essential amino acids (EAA) cannot be made de novo in metazoans but must be obtained from diet, the δ13C value of the primary producer is preserved through the food web. Therefore, the δ13C values of EAAs act as a unique signature of different primary producers and can be used to fingerprint the dominant carbon (C) source driving primary production at the base of the food web. In littoral ecosystems, such as the California Upwelling System (CUS), the likely dominant C sources of suspended particulate organic matter (POM) pool are kelp, upwelling phytoplankton or estuarine phytoplankton. While bulk isotopes of C and N are used extensively to resolve relative consumer hierarchy or shifting diet in a food web, we found that the δ13C bulk values in mussels cannot distinguish exact source in littoral ecosystems. Here we show 15 sites within the CUS, between Cape Blanco, OR and La Jolla, CA where mussels were sampled and analyzed for both bulk δ13C and CSI-AA. We found no latitudinal trends, but rather average bulk δ13C values for the entire coastal record were highly consistent (-15.7 ± 0.9‰). The bulk record would suggest either nutrient provisioning from kelp or upwelled phytoplankton, but 13C-AA fingerprinting confines these two sources to upwelling. This suggests that mussels are recording integrated coastal phytoplankton values, with the enriched �

Spawning of the chilean hake (Merluccius gayi in the upwelling system off Talcahuano in relation to oceanographic features

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Cristian A. Vargas

2001-06-01

Full Text Available Previous studies have shown that the upwelling area off Talcahuano, in central-south Chile, is an important spawning zone for the hake Merluccius gayi. We document the results of a study designed to assess the importance of oceanographic features on the horizontal and vertical distribution of hake eggs and larvae. Ichthyoplankton samples and oceanographic data (CTDO casts, and wind speed and direction were collected during a cruise carried out off Talcahuano (36º22´S-37º10´S in early spring (October 1996, which included a grid of 61 stations up to 60 nm offshore. The oceanographic information obtained revealed the presence of an upwelling plume at Lavapie Point (southern zone extending northward over the shelf, and the presence of a warmer water parcel close to shore in the northern area. Peak egg densities occurred in this northern area over the shelf, in a nucleus located at the shoreward moving deeper layer (40-100 m deep and associated with the upwelling front about 20-30 nm from shore. The highest larval abundance also occurred in the northern area over the shelf and in the deeper layer but closer to shore than the egg nucleus. Because the timing (early spring and location of spawning (at depth, over the shelf and in association with frontal structures are also shared by other hake species in upwelling areas, we propose that they may be part of a more commonly developed strategy to enhance offspring survival in coastal upwelling areas of eastern boundary currents.

The effects of spilled oil on coastal ecosystems: Lessons from the Exxon Valdez spill: Chapter 11

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Bodkin, James L.; Esler, Daniel N.; Rice, Stanley D.; Matkin, Craig O.; Ballachey, Brenda E.; Maslo, Brooke; Lockwood, Julie L.

2014-01-01

Oil spilled from ships or other sources into the marine environment often occurs in close proximity to coastlines, and oil frequently accumulates in coastal habitats. As a consequence, a rich, albeit occasionally controversial, body of literature describes a broad range of effects of spilled oil across several habitats, communities, and species in coastal environments. This statement is not to imply that spilled oil has less of an effect in pelagic marine ecosystems, but rather that marine spills occurring offshore may be less likely to be detected, and associated effects are more difficult to monitor, evaluate, and quantify (Peterson et al., 2012). As a result, we have a much greater awareness of coastal pollution, which speaks to our need to improve our capacities in understanding the ecology of the open oceans. Conservation of coastal ecosystems and assessment of risks associated with oil spills can be facilitated through a better understanding of processes leading to direct and indirect responses of species and systems to oil exposure.It is also important to recognize that oil spilled from ships represents only ~9% of the nearly 700 000 barrels of petroleum that enter waters of North America annually from anthropogenic sources (NRC, 2003). The immediate effects of large spills can be defined as acute, due to the obvious and dramatic effects that are observed. In contrast, the remaining 625 000 barrels that are released each year can be thought of as chronic non-point pollution, resulting from oil entering the coastal ocean as runoff in a more consistent but much less conspicuous rate. In this chapter, we primarily address the effects of large oil spills that occur near coastlines and consider their potential for both acute and chronic effects on coastal communities. As described below, in some instances, the effects from chronic exposure may meet or exceed the more evident acute effects from large spills. Consequently, although quantifying chronic effects

Contribution of Cultural Ecosystem Services to Natural Capital in the coastal area of Civitavecchia (Latium, Italy)

Science.gov (United States)

Marcelli, Marco; Madonia, Alice; Tofani, Anna; Molino, Chiara; Manfredi Frattarelli, Francesco

2017-04-01

Natural Capital evaluation is emerging as a fundamental tool to support the management of natural resources. Indeed, the achievement of the compatibility among their multiple uses, often in conflict in coastal areas, is a priority to avoid the increasing undesirable effects which threat both ecosystems and human health and well-being. It represents the scientific basis for actions needed to enhance the conservation and sustainable use of those systems and their contribution to human well-being. Furthermore the Millennium Ecosystem Assessment (called by Kofi Annan in 2000), assessed the consequences of ecosystem change for human well-being, and in particular, the analysis method has been centered on the linkages between "ecosystem services" and human well-being. This "Ecosystem Approach" allows to evaluate the consequences of ecosystems changes on human well-being through the assessment of the Ecosystem Services (ES), which are defined as "the benefits that people obtain from ecosystems". These include provisioning services (food, water, timber, etc.), regulating services (climate, floods, disease, etc.); cultural services (recreational, aesthetic and spiritual benefits) and supporting services (soil formation, photosynthesis, nutrient cycling, etc.) Also the reference guidelines for European Environmental Policy (Marine Strategy Framework Directive 2008/56 / EC - MSFD; Maritime Spatial Planning Directive 2014/89 / EC - MSP) are based on the principle of the Ecosystem Approach to define the monitoring criteria of marine and maritime space management ecosystems. The assessment of ES provided by Natural Capital cannot overlook the integration of ecological data with economic and socio-cultural ones, since they are considered as the direct and indirect contributions to human well-being provided by ecosystems. Cultural Ecosystem Services (CES), often omitted in the cost-benefit impact studies, has been receiving increasing interest from the scientific community in order

Marine Phytophthora species can hamper conservation and restoration of vegetated coastal ecosystems.

Science.gov (United States)

Govers, Laura L; Man In 't Veld, Willem A; Meffert, Johan P; Bouma, Tjeerd J; van Rijswick, Patricia C J; Heusinkveld, Jannes H T; Orth, Robert J; van Katwijk, Marieke M; van der Heide, Tjisse

2016-08-31

Phytophthora species are potent pathogens that can devastate terrestrial plants, causing billions of dollars of damage yearly to agricultural crops and harming fragile ecosystems worldwide. Yet, virtually nothing is known about the distribution and pathogenicity of their marine relatives. This is surprising, as marine plants form vital habitats in coastal zones worldwide (i.e. mangrove forests, salt marshes, seagrass beds), and disease may be an important bottleneck for the conservation and restoration of these rapidly declining ecosystems. We are the first to report on widespread infection of Phytophthora and Halophytophthora species on a common seagrass species, Zostera marina (eelgrass), across the northern Atlantic and Mediterranean. In addition, we tested the effects of Halophytophthora sp. Zostera and Phytophthora gemini on Z. marina seed germination in a full-factorial laboratory experiment under various environmental conditions. Results suggest that Phytophthora species are widespread as we found these oomycetes in eelgrass beds in six countries across the North Atlantic and Mediterranean. Infection by Halophytophthora sp. Zostera, P. gemini, or both, strongly affected sexual reproduction by reducing seed germination sixfold. Our findings have important implications for seagrass ecology, because these putative pathogens probably negatively affect ecosystem functioning, as well as current restoration and conservation efforts. © 2016 The Author(s).

Iberian and California-Oregon Upwelling Systems: trends and status of two upwelling systems at the same latitude over the last four decades.

Science.gov (United States)

Barreiro, B.; Barton, E. D.

2012-04-01

The study of Eastern Boundary Upwelling Systems is of vital importance, given the interest in rational management of the fisheries resources. The high level of biogeochemical activity associated with the physical process of upwelling increases primary production and enriches the living resources of these areas. This presentation focuses on the variability of these physical processes on daily to interdecadal scales, in an investigation of the effects of climate change in the Iberian and California-Oregon Upwelling Systems. The Upwelling Index (UI) was analysed for the period 1967-2010 at 35.5-44.5°N in both areas. The two systems differ in that the magnitudes of upwelling intensity off California-Oregon are 3.3 higher than off Iberia but they show a similar latitudinal behaviour. The annual/interannual scale variability of upwelling can be represented by the recently introduced Cumulative Upwelling Index (CUI) based on summing the mean daily UI. The seasonal cycle results show the length of upwelling season increases southwards from 180 to 300 days and a net upwelling occurs only for latitudes lower than 43°N. On the interannual scales, the CUI showed a roughly linear change at high and low latitudes (R>0.9), with slopes between 250 and -130 m3 s-1 km-1 day-1 in Iberian and 620 and -290 m3 s-1 km-1 day-1 in California-Oregon. The central areas (40.5-42.5°N) are less stable and shifted between net upwelling and downwelling over extended periods. This information helps us contextualize the present state of the study area and interpreted ongoing intensive process-oriented studies within the longer term variability.

Linking restoration ecology with coastal dune restoration

Science.gov (United States)

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

2013-10-01

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

Population parameters and the relationships between environmental factors and abundance of the Acetes americanus shrimp (Dendrobranchiata: Sergestidae near a coastal upwelling region of Brazil

Directory of Open Access Journals (Sweden)

Ana Paula Freitas dos Santos

2015-09-01

Full Text Available AbstractThe population dynamics of Acetes americanus was investigated, focusing on the sex ratio, individual growth, longevity, recruitment and relationship between abundance and environmental factors in the region of Macaé, strongly influenced by coastal upwelling. Otter trawl net samplings were performed from July 2010 to June 2011 at two points (5 m and 15 m. Nearly 19,500 specimens, predominantly females (77.15%, were captured. Their sizes, larger than that of males, indicated sexual dimorphism. Shrimps at lower latitudes present larger sizes and longer longevity than those from higher latitudes. This difference is probably due to low temperatures and high primary productivity. Though no statistical correlation was found between abundance and environmental factors, the species was more abundant in temperatures closer to 20.0º C and in months with high chlorophyll-a levels. Due to the peculiar characteristics of this region, A. americanusshowed greater differences in size and longevity than individuals sampled in other studies undertaken in the continental shelf of Southeast Brazil.

Local ecological knowledge related with marine ecosystems in two coastal communities: El Valle and Sapzurro

International Nuclear Information System (INIS)

Correa, Sandra Liliana; Turbay, Sandra; Velez, Madelene

2012-01-01

The inhabitants of the Colombian coastal populations of El Valle, in the Pacific, and Sapzurro, in the Caribbean Darien, have ecological knowledge about coastal ecosystems that is a result of their constant relation with the sea, through fishing and navigation. The sea is a source of food and economical resources, but it is also the sphere where the male personality is forged. The accurate knowledge about mangrove, coral, coral reef, beaches and fishing grounds has been enriched through the dialog between local inhabitants and researchers in the conservation biology field. However, the tensions with researchers and environmental authorities still exist. The paper suggests that local ecological knowledge studies could be a starting point for maintaining a more horizontal dialogue between environmentalist and the populations with livelihoods derived of fishing.

Latitudinal variation in the reproductive cycle of two bivalves with contrasting biogeographical origin along the Humboldt Current Upwelling Ecosystem

Directory of Open Access Journals (Sweden)

Roberto A. Uribe

2012-10-01

Full Text Available Argopecten purpuratus (Lamarck, 1819 and Mesodesma donacium (Lamarck, 1818 are bivalves that inhabit the Humboldt Current Upwelling Ecosystem. They have contrasting biogeographical origins, suggesting that their responses to exogenous factors should differ. Using circular statistics, we examine synchrony/asynchrony in the reproductive cycle between populations of each species. The results indicate that there is reproductive asynchrony in both species along their distributional range. However, there was synchrony for A. purpuratus in several location-pairs, including Paita-Chimbote, Chimbote-Callao, Callao-Pisco and Pisco-Antofagasta. For M. donacium, there were only two synchronic groups: Camaná-Capellanía-Mehuín and Hornitos-Peñuelas-Longotoma-La Ligua-Cucao-Quilanlar. A. purpuratus showed gametogenenic activity throughout the year. In contrast, M. donacium showed strong seasonality, with gametogenesis in winter and spawning in spring/summer. In conclusion, the patterns observed for these sympatric species suggest that on a large scale the reproductive cycles follow the expected patterns for the contrasting biogeographic origin of each species, so it could be argued that they are modulated by endogenous factors. However, at a local scale, the reproductive cycles of these species show variation, likely determined by local oceanographic or hydrographic processes.

Bacterial and Archaeal Communities Variability Associated with Upwelling and Anthropogenic Pressures in the Protection Area of Arraial do Cabo (Cabo Frio region - RJ).

Science.gov (United States)

Coelho-Souza, Sergio A; Araújo, Fábio V; Cury, Juliano C; Jesus, Hugo E; Pereira, Gilberto C; Guimarães, Jean R D; Peixoto, Raquel S; Dávila, Alberto M R; Rosado, Alexandre S

2015-09-01

Upwelling systems contain a high diversity of pelagic microorganisms and their composition and activity are defined by factors like temperature and nutrient concentration. Denaturing gradient gel electrophoresis (DGGE) technique was used to verify the spatial and temporal genetic variability of Bacteria and Archaea in two stations of the Arraial do Cabo coastal region, one under upwelling pressure and another under anthropogenic pressure. In addition, biotic and abiotic variables were measured in surface and deep waters from three other stations between these stations. Six samplings were done during a year and adequately represented the degrees of upwelling and anthropogenic pressures to the system. Principal Component Analysis (PCA) showed negative correlations between the concentrations of ammonia and phosphorous with prokaryotic secondary production and the total heterotrophic bacteria. PCA also showed negative correlation between temperature and the abundance of prokaryotic cells. Bacterial and archaeal compositions were changeable as were the oceanographic conditions, and upwelling had a regional pressure while anthropogenic pressure was punctual. We suggest that the measurement of prokaryotic secondary production was associated with both Bacteria and Archaea activities, and that substrate availability and temperature determine nutrients cycling.

Microlevel mapping of coastal geomorphology and coastal resources of Rameswaram island, India: A remote sensing and GIS perspective

Digital Repository Service at National Institute of Oceanography (India)

Nobi, E.P.; Shivaprasad, A.; Karikalan, R.; Dilipan, E.; Thangaradjou, T.; Sivakumar, K.

Coastal areas are facing serious threats from both manmade and natural disturbances; coastal erosion, sea-level variation, and cyclones are the major factors that alter the coastal topography and coastal resources of the island ecosystems...

The ichthyoplankton assemblage of the Canaries-African Coastal Transition Zone: A review

Science.gov (United States)

Rodriguez, J. M.; Moyano, M.; Hernandez-Leon, S.

2009-12-01

In this paper we review information on the ichthyoplankton assemblage of the Canaries-African Coastal Transition Zone (C-ACTZ). This CTZ shows the singularity that the Canary Archipelago interrupts the main flow of the Canary Current and Trade Winds, introducing large mesoscale variability, in the form of island warm wakes and cyclonic and anticyclonic eddies downstream of the islands. Besides, upwelling filaments stretch towards the archipelago from the African coastal upwelling, transporting phytoplankton, zooplankton and fish larvae. They also interact with eddies shed from the islands to exchange water properties and biogenic material. All these mesoscale features influence the composition, structure, abundance and distribution of the larval fish community (LFC) of the region. The Canary Current (CC) and eddies shed from the islands drag larvae of island neritic fish species into the oceanic region and contribute, along warm wakes, to the horizontal distribution of fish larvae. Upwelling and upwelling filaments transport larvae of African neritic species into the oceanic region. These larvae dominate the LFC and account for the relatively high average larval fish abundance found in the C-ACTZ during the summer upwelling season. Filaments originated in the region of Cape Juby-Cape Bojador are entrained around a quasi-permanent cyclonic eddy, trapped between Gran Canaria Island and the African coast, forming a system through which most of the African neritic larvae may return to the African shelf. However, some larvae reach the eastern islands of the Canary archipelago and they may be spread all over the neritic region of the archipelago by eddies shed from the islands. Also in summer, the distribution of the LFC of the C-ACTZ is vertically stratified and fish larvae seem to carry out little or not diel vertical migration. Overall, this study highlights the strong relationship between mesoscale oceanographic processes and the LFC in the C-ACTZ.

From nitrogen enrichment to oxygen depletion: a mechanistic model of coastal marine ecosystems response

DEFF Research Database (Denmark)

Cosme, Nuno Miguel Dias; Koski, Marja; Hauschild, Michael Zwicky

Nitrogen (N) emissions from anthropogenic sources may enrich coastal waters and lead to marine eutrophication impacts. Processes describing N-limited primary production (PP), zooplankton grazing, and bacterial respiration of sinking organic carbon, were modelled to quantify the potential dissolved...... oxygen (DO) consumption as a function of N input. Such indicator is the basis for an eXposure Factor (XF) applied in Life Cycle Impact Assessment (LCIA) to estimate impacts from N enrichment. The Large Marine Ecosystems (LME) biogeographical classification system was adopted to address the spatial...

Isotopic and enzymatic analyses of planktonic nitrogen utilisation in the vicinity of Cape Sines (Portugal) during weak upwelling activity

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Slawyk, Gerd; Coste, Bernard; Collos, Yves; Rodier, Martine

1997-01-01

Using measurements of 15N uptake and activities of nitrate reductase and glutamine synthetase, the utilization of nitrogenous nutrients by microplankton in the Portuguese upwelling area was investigated. During this cruise the euphotic zone of coastal waters was in most cases bisected by a nitracline forming two layers. Total inorganic nitrogen uptake rates (NH 4+ + NO 3-) in the upper mixed and nitrate-impoverished layer ranged from 0.1 to 0.8 nM h -1 and were primarily supported by regenerated (ammonium) nitrogen (62-97%), whereas they varied between 0.9 and 10.4 nM h -1 in the deep nitrate-rich layer and were mainly driven by new (nitrate) nitrogen (52-82%). Depth profiles of Chl a-specific uptake rates for ammonium and nitrate paralleled those of absolute uptake rates, i.e. values of VNH 4+Chl were highest (up to 16.1 nmol μg -1 h -1) in nitrate-poor surface waters while values of VNO 3-Chl were maximum (up to 8.4 nmol μg -1 h -1)within the nitracline. This latter vertical ordering of planktonic nitrogen nutrition was consistent with an aged upwelling situation. However, applying several indices of cell metabolism and nutritional status, such as 15N uptake/enzyme activity, surge uptake internally controlled uptake, and V maxChl/K t ratios, we were able to demonstrate that the phytoplankton assemblages inhabiting the nutrient-impoverished upper layer still bore the signature of physically mediated nitrogen (nitrate) supply generated by active upwelling that had occurred during the week before our visit to the area. This signature was the most evident in samples from the station furthest inshore and faded with distance from shore as a result of the deepening of the nitrate isopleths (weakening of upwelling activity), which showed the same offshore trend. The appearance of nitrate-rich waters at the surface, after a strong pulse of upwelling favourable winds just before the end of the cruise, led to a five-fold increase in average (over the euphotic zone

Stable nitrogen isotopes in coastal macroalgae: Geographic and anthropogenic variability

Energy Technology Data Exchange (ETDEWEB)

Viana, Inés G., E-mail: ines.gonzalez@co.ieo.es; Bode, Antonio

2013-01-15

Growing human population adds to the natural nitrogen loads to coastal waters. Both anthropogenic and natural nitrogen is readily incorporated in new biomass, and these different nitrogen sources may be traced by the measurement of the ratio of stable nitrogen isotopes (δ{sup 15}N). In this study δ{sup 15}N was determined in two species of macroalgae (Ascophyllum nodosum and Fucus vesiculosus), and in nitrate and ammonium to determine the relative importance of anthropogenic versus natural sources of nitrogen along the coast of NW Spain. Both algal species and nitrogen sources showed similar isotopic enrichment for a given site, but algal δ{sup 15}N was not related to either inorganic nitrogen concentrations or δ{sup 15}N in the water samples. The latter suggests that inorganic nitrogen inputs are variable and do not always leave an isotopic trace in macroalgae. However, a significant linear decrease in macroalgal δ{sup 15}N along the coast is consistent with the differential effect of upwelling. Besides this geographic variability, the influence of anthropogenic nitrogen sources is evidenced by higher δ{sup 15}N in macroalgae from rias and estuaries compared to those from open coastal areas and in areas with more than 15 × 10{sup 3} inhabitants in the watershed. These results indicate that, in contrast with other studies, macroalgal δ{sup 15}N is not simply related to either inorganic nitrogen concentrations or human population size but depends on other factors as the upwelling or the efficiency of local waste treatment systems. - Highlights: ► Anthropogenic versus upwelling nitrogen effect on macroalgal δ{sup 15}N was studied. ► The influence of populations and upwelling has not been made before on macroalgal δ{sup 15}N. ► Natural variability has not been taken into account in most biomonitoring studies. ► Upwelling explains most of the variability in δ{sup 15}N in macroalgae.

Modeled Sea Level Rise Impacts on Coastal Ecosystems at Six Major Estuaries on Florida’s Gulf Coast: Implications for Adaptation Planning

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Birch, Anne P.; Brenner, Jorge; Gordon, Doria R.

2015-01-01

The Sea Level Affecting Marshes Model (SLAMM) was applied at six major estuaries along Florida’s Gulf Coast (Pensacola Bay, St. Andrews/Choctawhatchee Bays, Apalachicola Bay, Southern Big Bend, Tampa Bay and Charlotte Harbor) to provide quantitative and spatial information on how coastal ecosystems may change with sea level rise (SLR) and to identify how this information can be used to inform adaption planning. High resolution LiDAR-derived elevation data was utilized under three SLR scenarios: 0.7 m, 1 m and 2 m through the year 2100 and uncertainty analyses were conducted on selected input parameters at three sites. Results indicate that the extent, spatial orientation and relative composition of coastal ecosystems at the study areas may substantially change with SLR. Under the 1 m SLR scenario, total predicted impacts for all study areas indicate that coastal forest (-69,308 ha; -18%), undeveloped dry land (-28,444 ha; -2%) and tidal flat (-25,556 ha; -47%) will likely face the greatest loss in cover by the year 2100. The largest potential gains in cover were predicted for saltmarsh (+32,922 ha; +88%), transitional saltmarsh (+23,645 ha; na) and mangrove forest (+12,583 ha; +40%). The Charlotte Harbor and Tampa Bay study areas were predicted to experience the greatest net loss in coastal wetlands The uncertainty analyses revealed low to moderate changes in results when some numerical SLAMM input parameters were varied highlighting the value of collecting long-term sedimentation, accretion and erosion data to improve SLAMM precision. The changes predicted by SLAMM will affect exposure of adjacent human communities to coastal hazards and ecosystem functions potentially resulting in impacts to property values, infrastructure investment and insurance rates. The results and process presented here can be used as a guide for communities vulnerable to SLR to identify and prioritize adaptation strategies that slow and/or accommodate the changes underway. PMID:26207914

Light-stress avoidance mechanisms in a Sphagnum-dominated wet coastal Arctic tundra ecosystem in Alaska.

Science.gov (United States)

Zona, D; Oechel, Walter C; Richards, James H; Hastings, Steven; Kopetz, Irene; Ikawa, Hiroki; Oberbauer, Steven

2011-03-01

The Arctic experiences a high-radiation environment in the summer with 24-hour daylight for more than two months. Damage to plants and ecosystem metabolism can be muted by overcast conditions common in much of the Arctic. However, with climate change, extreme dry years and clearer skies could lead to the risk of increased photoxidation and photoinhibition in Arctic primary producers. Mosses, which often exceed the NPP of vascular plants in Arctic areas, are often understudied. As a result, the effect of specific environmental factors, including light, on these growth forms is poorly understood. Here, we investigated net ecosystem exchange (NEE) at the ecosystem scale, net Sphagnum CO2 exchange (NSE), and photoinhibition to better understand the impact of light on carbon exchange from a moss-dominated coastal tundra ecosystem during the summer season 2006. Sphagnum photosynthesis showed photoinhibition early in the season coupled with low ecosystem NEE. However, later in the season, Sphagnum maintained a significant CO2 uptake, probably for the development of subsurface moss layers protected from strong radiation. We suggest that the compact canopy structure of Sphagnum reduces light penetration to the subsurface layers of the moss mat and thereby protects the active photosynthetic tissues from damage. This stress avoidance mechanism allowed Sphagnum to constitute a significant percentage (up to 60%) of the ecosystem net daytime CO2 uptake at the end of the growing season despite the high levels of radiation experienced.

Coral Reef and Coastal Ecosystems Decision Support Workshop April 27-29, 2010 Caribbean Coral Reef Institute, La Parguera, Puerto Rico

Science.gov (United States)

The U.S. Environmental Protection Agency (EPA) and Caribbean Coral Reef Institute (CCRI) hosted a Coral Reef and Coastal Ecosystems Decision Support Workshop on April 27-28, 2010 at the Caribbean Coral Reef Institute in La Parguera, Puerto Rico. Forty-three participants, includin...

Ecomorphology of crabs and swimming crabs (Crustacea DecapodaBrachyura from coastal ecosystems

Directory of Open Access Journals (Sweden)

Murilo Zanetti Marochi

Full Text Available Abstract Brachyuran crabs are one of the most diverse taxa of crustaceans, occurring in almost all coastal habitats. Due to their high morphological diversification, the authors sought to ascertain the existence of morphological patterns related to the habitat of coastal brachyuran crabs. We analyzed 17 species from mangrove forests, rocky shores, sandy beaches and exclusively aquatic marine/estuarine ecosystems. A total of 16 linear measurements of males and 17 of females were obtained for each habitat. We were able to discriminate three functional groups of crab species, based on their habitat: 1. Complex Substrates, 2. Semiterrestrial, 3. Exclusively Aquatic. The species belonging to the Complex Substrates group had long ambulatory legs, as well as being heteroquely related to uneven terrain. Semiterrestrial species showed ambulatory legs of different sizes, allowing them to walk easily on the terrestrial terrain due to the long fourth ambulatory leg, and long eyestalks which are important for visual communication. Exclusively Aquatic species showed the largest carapace widths and the shortest eyestalks. The presence of different crab lineages in the environments analyzed allows us to demonstrate the clear evolutionary convergence, by which the crabs adapted to their specific habitat and environment.

Diurnal Variability of the inner-shelf circulation in the lee of a cape under upwelling conditions

Science.gov (United States)

Lamas, Luisa; Peliz, Álvaro; Marchesiello, Patrick

2013-04-01

The circulation over the inner-shelf is a key component of shelf dynamics and an important mechanism for cross-shore exchange on most shelves. Yet our understanding of the cross-shore circulation and how it depends on different forcing conditions, bathymetry and stratification remains poor due in part to sparse observations and the difficulty of resolving spatial and temporal scales within the inner-shelf. Most studies of cross-shore transport on the inner-shelf consider only a 2D circulation, due to coastal upwelling or downwelling and assume along-shore uniformity. However, divergence in the along-shore and cross-shore flows may occur with the presence of complex coastline topography or subtle bathymetric features, and can drive substantial horizontal cross-shore exchange, with same order of magnitude as coastal upwelling and downwelling. A recent study using observational data collected near cape Sines, Portugal, showed that not only wind, waves and tides are important forcing mechanisms of the inner-shelf circulation, but also that the along-shore pressure gradient plays a major role on driving cross-shore exchange. A modeling study was conducted in order to study the complexity of the inner-shelf dynamics, in the presence of a cape. A simplified configuration was used in order to isolate the effects of individual processes: wind, heat fluxes, tides and waves. The preliminary results of the effects of these processes on the inner-shelf circulation will be presented.

Contrasting biogeochemical responses of ENSO induced upwelling variability in the Humboldt Current System

Science.gov (United States)

Franco, Ana C.; Gruber, Nicolas; Münnich, Matthias

2017-04-01

The Humboldt Current System (HCS) is one of the most productive ecosystems in the world. This high productivity is supported by a large input of nutrients from the subsurface layers to the surface due to year-round upwelling. However, upwelling also supplies waters with low pH and low aragonite saturation state potentially affecting many organisms, especially those that calcify. The influence, extent and source of upwelled water vary substantially on interannual timescales in association with the El Niño/Southern Oscillation (ENSO) phenomenon, generating natural contrasting responses on the biogeochemistry of this system. Here we analyze these responses using an eddy resolving, basin-scale ocean model that covers the whole Pacific Ocean with high resolution (4 km) on the west coast of South America. We performed a simulation of the last 30 years (hindcast simulation) that allows us to investigate the influence of at least eight El Niño episodes and eight La Niña episodes on productivity variations and changes in oxygen concentration and aragonite saturation state. An absolute change in surface omega aragonite of almost 2 units, as well as an absolute change of the aragonite saturation depth of 200 m result from the change of an El Niño phase to a La Niña phase. This variability is on the same order of magnitude as the projected change in the aragonite saturation state in a centennial timescale. During La Niña events, a lower aragonite saturation state values and reduced oxygen concentration in the surface layer are a direct consequence of enhanced upwelling and increased net primary productivity. The opposite is true during El Niño events, where high values of omega aragonite occur in concordance with extraordinarily low net primary productivity values.

Belowground dynamics in mangrove ecosystems

Science.gov (United States)

McKee, Karen L.

2004-01-01

Mangrove ecosystems are tropical/subtropical communities of primarily tree species that grow in the intertidal zone. These tidal communities are important coastal ecosystems that are valued for a variety of ecological and societal goods and services (fig. 1). Mangrove wetlands are important filters of materials moving between the land and sea, trapping sediment, nutrients, and pollutants in runoff from uplands and preventing their direct introduction into sensitive marine ecosystems such as seagrass beds and coral reefs. Mangroves serve as nursery grounds and refuge for a variety of organisms and are consequently vital to the biological productivity of coastal waters. Furthermore, because mangroves are highly resilient to disturbances such as hurricanes, they represent a self-sustaining, protective barrier for human populations living in the coastal zone. Mangrove ecosystems also contribute to shoreline stabilization through consolidation of unstable mineral sediments and peat formation. In order to help conserve mangrove ecoystems, scientists with the United States Geological Survey (USGS) at the National Wetlands Research Center are working to more fully understand the dynamics that impact these vital ecosystems.

Tropical South-East Atlantic response to ENSO as an ecosystem ...

African Journals Online (AJOL)

Cases were selected based on indices of Pacific sea surface temperature and South-East African rainfall. ... an El Niño event, and higher sardine Sardinops sagax catches tend to follow a La Niña event, through the northward and southward shift respectively of the South Atlantic anticyclone and attendant coastal upwelling.

Improving the Remote Sensing Retrieval of Phytoplankton Functional Types (PFT Using Empirical Orthogonal Functions: A Case Study in a Coastal Upwelling Region

Directory of Open Access Journals (Sweden)

Marco Correa-Ramirez

2018-03-01

Full Text Available An approach that improves the spectral-based PHYSAT method for identifying phytoplankton functional types (PFT in satellite ocean-color imagery is developed and applied to one study case. This new approach, called PHYSTWO, relies on the assumption that the dominant effect of chlorophyll-a (Chl-a in the normalized water-leaving radiance (nLw spectrum can be effectively isolated from the signal of accessory pigment biomarkers of different PFT by using Empirical Orthogonal Function (EOF decomposition. PHYSTWO operates in the dimensionless plane composed by the first two EOF modes generated through the decomposition of a space–nLw matrix at seven wavelengths (412, 443, 469, 488, 531, 547, and 555 nm. PFT determination is performed using orthogonal models derived from the acceptable ranges of anomalies proposed by PHYSAT but adjusted with the available regional and global data. In applying PHYSTWO to study phytoplankton community structures in the coastal upwelling system off central Chile, we find that this method increases the accuracy of PFT identification, extends the application of this tool to waters with high Chl-a concentration, and significantly decreases (~60% the undetermined retrievals when compared with PHYSAT. The improved accuracy of PHYSTWO and its applicability for the identification of new PFT are discussed.

Surface distribution of brachyuran megalopae and ichthyoplankton in the Columbia River plume during transition from downwelling to upwelling conditions

Science.gov (United States)

Roegner, G. Curtis; Daly, Elizabeth A.; Brodeur, Richard D.

2013-06-01

In the California Current coastal boundary zone, the spring transition between downwelling and upwelling conditions, along with the fluctuating structure of the Columbia River plume, creates highly dynamic interactions. In this study, we investigated whether the surface distribution of brachyuran larvae and ichthyoplankton would track the dynamics of the Columbia River plume. By happenstance, the cruise period coincided with the spring transition from downwelling to sustained upwelling conditions in 2010, a year when the transition was delayed and Columbia River flow was substantially higher than average. We used time series of wind and freshwater input to evaluate the influence of physical forcing on oceanographic patterns, and sampled hydrography and surface plankton concentrations within a 182 km2 grid off Willapa Bay, WA. Additionally, two longer transects, one cross-shelf and the other along-shore, were made to discern the extent of plume influence on larval crab and fish abundance. We found that plume waters that were trapped in a northward-flowing coastal-boundary current during downwelling conditions were advected offshore after several days of upwelling-favorable winds. Neustonic collections of brachyuran larvae and ichthyoplankton varied in response to this large seaward advective event. Megalopae of cancrid crabs exhibited patterns of both offshore transport (Cancer oregonensis/productus) and nearshore retention (C. magister). Additionally, abundant numbers of large juvenile widow (Sebastes entomelas) and yellowtail (S. flavidus) rockfish of a size appropriate for settlement were sampled during a period when ocean conditions favored high recruitment success. These results demonstrated that the response of planktonic crab larvae and ichthyoplankton to large-scale advection varied by species, with larger and more vagile fish exhibiting less evidence of passive transport than smaller crab larvae. Importantly, portions of the planktonic fish and crab

Ecomarkets for conservation and sustainable development in the coastal zone.

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Fujita, Rod; Lynham, John; Micheli, Fiorenza; Feinberg, Pasha G; Bourillón, Luis; Sáenz-Arroyo, Andrea; Markham, Alexander C

2013-05-01

Because conventional markets value only certain goods or services in the ocean (e.g. fish), other services provided by coastal and marine ecosystems that are not priced, paid for, or stewarded tend to become degraded. In fact, the very capacity of an ecosystem to produce a valued good or service is often reduced because conventional markets value only certain goods and services, rather than the productive capacity. Coastal socio-ecosystems are particularly susceptible to these market failures due to the lack of clear property rights, strong dependence on resource extraction, and other factors. Conservation strategies aimed at protecting unvalued coastal ecosystem services through regulation or spatial management (e.g. Marine Protected Areas) can be effective but often result in lost revenue and adverse social impacts, which, in turn, create conflict and opposition. Here, we describe 'ecomarkets' - markets and financial tools - that could, under the right conditions, generate value for broad portfolios of coastal ecosystem services while maintaining ecosystem structure and function by addressing the unique problems of the coastal zone, including the lack of clear management and exclusion rights. Just as coastal tenure and catch-share systems generate meaningful conservation and economic outcomes, it is possible to imagine other market mechanisms that do the same with respect to a variety of other coastal ecosystem goods and services. Rather than solely relying on extracting goods, these approaches could allow communities to diversify ecosystem uses and focus on long-term stewardship and conservation, while meeting development, food security, and human welfare goals. The creation of ecomarkets will be difficult in many cases, because rights and responsibilities must be devolved, new social contracts will be required, accountability systems must be created and enforced, and long-term patterns of behaviour must change. We argue that efforts to overcome these obstacles

Effects of near-future ocean acidification, fishing, and marine protection on a temperate coastal ecosystem.

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Cornwall, Christopher E; Eddy, Tyler D

2015-02-01

Understanding ecosystem responses to global and local anthropogenic impacts is paramount to predicting future ecosystem states. We used an ecosystem modeling approach to investigate the independent and cumulative effects of fishing, marine protection, and ocean acidification on a coastal ecosystem. To quantify the effects of ocean acidification at the ecosystem level, we used information from the peer-reviewed literature on the effects of ocean acidification. Using an Ecopath with Ecosim ecosystem model for the Wellington south coast, including the Taputeranga Marine Reserve (MR), New Zealand, we predicted ecosystem responses under 4 scenarios: ocean acidification + fishing; ocean acidification + MR (no fishing); no ocean acidification + fishing; no ocean acidification + MR for the year 2050. Fishing had a larger effect on trophic group biomasses and trophic structure than ocean acidification, whereas the effects of ocean acidification were only large in the absence of fishing. Mortality by fishing had large, negative effects on trophic group biomasses. These effects were similar regardless of the presence of ocean acidification. Ocean acidification was predicted to indirectly benefit certain species in the MR scenario. This was because lobster (Jasus edwardsii) only recovered to 58% of the MR biomass in the ocean acidification + MR scenario, a situation that benefited the trophic groups lobsters prey on. Most trophic groups responded antagonistically to the interactive effects of ocean acidification and marine protection (46%; reduced response); however, many groups responded synergistically (33%; amplified response). Conservation and fisheries management strategies need to account for the reduced recovery potential of some exploited species under ocean acidification, nonadditive interactions of multiple factors, and indirect responses of species to ocean acidification caused by declines in calcareous predators. © 2014 Society for Conservation Biology.

Our evolving conceptual model of the coastal eutrophication problem

Science.gov (United States)

Cloern, James E.

2001-01-01

A primary focus of coastal science during the past 3 decades has been the question: How does anthropogenic nutrient enrichment cause change in the structure or function of nearshore coastal ecosystems? This theme of environmental science is recent, so our conceptual model of the coastal eutrophication problem continues to change rapidly. In this review, I suggest that the early (Phase I) conceptual model was strongly influenced by limnologists, who began intense study of lake eutrophication by the 1960s. The Phase I model emphasized changing nutrient input as a signal, and responses to that signal as increased phytoplankton biomass and primary production, decomposition of phytoplankton-derived organic matter, and enhanced depletion of oxygen from bottom waters. Coastal research in recent decades has identified key differences in the responses of lakes and coastal-estuarine ecosystems to nutrient enrichment. The contemporary (Phase II) conceptual model reflects those differences and includes explicit recognition of (1) system-specific attributes that act as a filter to modulate the responses to enrichment (leading to large differences among estuarine-coastal systems in their sensitivity to nutrient enrichment); and (2) a complex suite of direct and indirect responses including linked changes in: water transparency, distribution of vascular plants and biomass of macroalgae, sediment biogeochemistry and nutrient cycling, nutrient ratios and their regulation of phytoplankton community composition, frequency of toxic/harmful algal blooms, habitat quality for metazoans, reproduction/growth/survival of pelagic and benthic invertebrates, and subtle changes such as shifts in the seasonality of ecosystem functions. Each aspect of the Phase II model is illustrated here with examples from coastal ecosystems around the world. In the last section of this review I present one vision of the next (Phase III) stage in the evolution of our conceptual model, organized around 5

Community response of zooplankton to oceanographic changes (2002-2012) in the central/southern upwelling system of Chile

Science.gov (United States)

Medellín-Mora, Johanna; Escribano, Ruben; Schneider, Wolfgang

2016-03-01

A 10-year time series (2002-2012) at Station 18 off central/southern Chile allowed us to study variations in zooplankton along with interannual variability and trends in oceanographic conditions. We used an automated analysis program (ZooImage) to assess changes in the mesozooplankton size structure and the composition of the taxa throughout the entire community. Oceanographic conditions changed over the decade: the water column became less stratified, more saline, and colder; the mixed layer deepened; and the oxygen minimum zone became shallower during the second half of the time series (2008-2012) in comparison with the first period (2002-2007). Both the size structure and composition of the zooplankton were significantly associated with oceanographic changes. Taxonomic and size diversity of the zooplankton community increased to the more recent period. For the second period, small sized copepods (1.5 mm) and medium size copepods (1-1.5 mm), whereas euphausiids, decapod larvae, appendicularian and ostracods increased their abundance during the second period. These findings indicated that the zooplankton community structure in this eastern boundary ecosystem was strongly influenced by variability of the upwelling process. Thus, climate-induced forcing of upwelling trends can alter the zooplankton community in this highly productive region with potential consequences for the ecosystem food web.

Case Study of the California Low Level Coastal Jet Comparisons Between Observed and Model-Estimated Winds and Temperatures using WRF and COAMPS

Science.gov (United States)

Tomé, Ricardo; Semedo, Alvaro; Ranjha, Raza; Tjernström, Michael; Svensson, Gunilla

2010-05-01

A low level coastal jet (LLCJ) is a low-troposphereic wind feature driven by the pressure gradient produced by a sharp contrast between high temperatures over land and lower temperatures over sea. This feature has been identified and studied in several areas of the world, where such a land-sea temperature contrast exist: off the coast of Somalia, near Lima, Peru, off the Mediterranean coast of Spain, in the Southwest coast of Africa, or in the South China Sea coast. Nevertheless, the California LLCJ is probably the most studied coastal jet in the world, with several studies available in the literature. Coastal jets have a notorious impact on coastal areas. Climatologically they are associated with coastal upwelling processes. The major coastal fishing grounds in the world are usually in areas of upwelling, and the abundance of fish at the surface is supported by the upwelled nutrient-rich waters from deeper levels. The effect of this upwelled water to the fishing industry and to the habitat of an enormous diversity of marine life is of paramount importance, and has led to numerous studies in this field. Littoral areas are usually densely populated, and often airports are built in areas where a LLCJ may occur. Thus, aviation operations are deeply influenced by this weather feature, which has a significant impact on the takeoff and landing of airplanes. Therefore the forecasting of LLCJ features is very important for several reasons.The forecasting skills of mesoscale models, while challenging in any region, become particularly complex near coastlines, where processes associated with the coastal boundary add additional complexity: interaction of the flow with the coastal orography, sharp sea-land temperature gradients, highly baroclinic environment, complex air-sea exchanging processes, etc. The purpose of this study is to assess the forecasting skills of the limited-area models WRF (Weather Research and Forecasting) and COAMPS® (Coupled Ocean-Atmosphere Mesoscale

Pliocene Warm Period Upwelling in the Southern Benguela Region

Science.gov (United States)

Petrick, B. F.; McClymont, E.; Felder, S.; Leng, M. J.; Rosell Mele, A.; Rueda, G.

2014-12-01

The mid-Pliocene has been proposed as a possible analogue for understanding future climate change and testing climate models. Previous work has shown that during the Pliocene the major upwelling systems were relatively warm, and thus either inactive, contracted, or upwelling warmer waters than present. Here we examine evidence from a core site located on the margins of the modern Benguela upwelling system, to test whether the upwelling cells had migrated or contracted relative to present during the Pliocene. We applied several organic geochemistry proxies and foraminiferal analyses to reconstruct the Pliocene history of ODP site 1087 (31º28'S, 15º19'E, 1374m water depth), including the UK37' index and TEX86 index (for reconstructing sea surface temperatures), chlorins (for estimating primary productivity) and planktonic foraminifera assemblages (for inferring water mass changes). These proxies show that between 3.5 and 3.0 Ma the southern Benguela region was significantly cooler than the northern Benguela region, the latter where the main upwelling cells are found today. Coupled with higher primary production, a shift in planktonic foraminifera assemblage, and an offset between the UK37' index and TEX86 index, we infer that more extensive upwelling was present in the southern Benguela region during the Pliocene. We infer that the main Benguela upwelling cells had shifted southward relative to today, as a result of changes in the local wind field. We find evidence for pronounced cooling and a shift in the planktonic foraminifera assemblage during the M2 and KM2 glacial stages, showing a sensitivity of Benguela upwelling to these short-lived climate events.

A conceptual framework for Lake Michigan coastal/nearshore ecosystems, with application to Lake Michigan Lakewide Management Plan (LaMP) objectives

Science.gov (United States)

Seelbach, Paul W.; Fogarty, Lisa R.; Bunnell, David Bo; Haack, Sheridan K.; Rogers, Mark W.

2013-01-01

The Lakewide Management Plans (LaMPs) within the Great Lakes region are examples of broad-scale, collaborative resource-management efforts that require a sound ecosystems approach. Yet, the LaMP process is lacking a holistic framework that allows these individual actions to be planned and understood within the broader context of the Great Lakes ecosystem. In this paper we (1) introduce a conceptual framework that unifies ideas and language among Great Lakes managers and scientists, whose focus areas range from tributary watersheds to open-lake waters, and (2) illustrate how the framework can be used to outline the geomorphic, hydrologic biological, and societal processes that underlie several goals of the Lake Michigan LaMP, thus providing a holistic and fairly comprehensive roadmap for tackling these challenges. For each selected goal, we developed a matrix that identifies the key ecosystem processes within the cell for each lake zone and each discipline; we then provide one example where a process is poorly understood and a second where a process is understood, but its impact or importance is unclear. Implicit in these objectives was our intention to highlight the importance of the Great Lakes coastal/nearshore zone. Although the coastal/nearshore zone is the important linkage zone between the watershed and open-lake zones—and is the zone where most LaMP issues are focused--scientists and managers have a relatively poor understanding of how the coastal/nearshore zone functions. We envision follow-up steps including (1) collaborative development of a more detailed and more complete conceptual model of how (and where) identified processes are thought to function, and (2) a subsequent gap analysis of science and monitoring priorities.

Seasonal climatology of hydrographic conditions in the upwelling region off northern Chile

Science.gov (United States)

Blanco, J. L.; Thomas, A. C.; Carr, M.-E.; Strub, P. T.

2001-06-01

Over 30 years of hydrographic data from the northern Chile (18°S-24°S) upwelling region are used to calculate the surface and subsurface seasonal climatology extending 400 km offshore. The data are interpolated to a grid with sufficient spatial resolution to preserve cross-shelf gradients and then presented as means within four seasons: austral winter (July-September), spring (October-December), summer (January-March), and fall (April-June). Climatological monthly wind forcing, surface temperature, and sea level from three coastal stations indicate equatorward (upwelling favorable) winds throughout the year, weakest in the north. Seasonal maximum alongshore wind stress is in late spring and summer (December-March). Major water masses of the region are identified in climatological T-S plots and their sources and implied circulation discussed. Surface fields and vertical transects of temperature and salinity confirm that upwelling occurs year-round, strongest in summer and weakest in winter, bringing relatively fresh water to the surface nearshore. Surface geostrophic flow nearshore is equatorward throughout the year. During summer, an anticyclonic circulation feature in the north which extends to at least 200 m depth is evident in geopotential anomaly and in both temperature and geopotential variance fields. Subsurface fields indicate generally poleward flow throughout the year, strongest in an undercurrent near the coast. This undercurrent is strongest in summer and most persistent and organized in the south (south of 21°S). A subsurface oxygen minimum, centered at ˜250 m, is strongest at lower latitudes. Low-salinity subsurface water intrudes into the study area near 100 m, predominantly in offshore regions, strongest during summer and fall and in the southernmost portion of the region. The climatological fields are compared to features off Baja within the somewhat analogous California Current and to measurements from higher latitudes within the Chile

L' upwelling de la côte atlantique du Maroc entre 1994 et 1998

Science.gov (United States)

Makaoui, Ahmed; Orbi, Abdelattif; Hilmi, Karim; Zizah, Soukaina; Larissi, Jamila; Talbi, Mohammed

2005-12-01

The pelagic ecosystem of the Moroccan Atlantic coast is influenced by the spatiotemporal variability of upwelling. The changes in the physicochemical and biological parameters as well as their interrelationship and regrouping by the principal components analysis allowed us to subdivide the Atlantic coast in four active areas: two areas located at the north of Cape Juby (28°N), characterised by a summery activity and two areas located at the south, active permanently, with a variable intensity. To cite this article: A. Makaoui et al., C. R. Geoscience 337 (2005).

7Be content in rainfall and soil deposition in South American coastal ecosystems

International Nuclear Information System (INIS)

Cardoso, R.; Ayub, J. Juri; Anjos, Roberto Meigikos dos; Cid, Alberto Silva; Velasco, H.

2011-01-01

soil deposition in a semiarid ecosystem at San Luis Province, central Argentina. Now, we are starting measurements in coastal ecosystems at Niteroi, southeastern Brazil. At this conference, we are going to present preliminary results on 7 Be content in rains, relationships with precipitation regime, and assess the 7 Be deposition in soil and its seasonality. (author)

Implications of Upwells as Hydrodynamic Jets in a Pulse Jet Mixed System

Energy Technology Data Exchange (ETDEWEB)

Pease, Leonard F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bamberger, Judith A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Minette, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2017-02-28

This report evaluates the physics of the upwell flow in pulse jet mixed systems in the Hanford Tank Waste Treatment and Immobilization Plant (WTP). Although the initial downward flow and radial flow from jets characteristic of pulse jet mixers (PJMs) has been analyzed, the upwells have received considerably less attention despite having significant implications for vessel mixing. Do the upwells behave like jets? How do the upwells scale? When will the central upwell break through? What proportion of the vessel is blended by the upwells themselves? Indeed, how the physics of the central upwell is affected by multiple PJMs (e.g., six in the proposed mixing vessels), non-Newtonian rheology, and significant multicomponent solids loadings remain unexplored.

Properties of Red Sea coastal currents

KAUST Repository

Churchill, J.H.

2014-02-14

Properties of coastal flows of the central Red Sea are examined using 2 years of velocity data acquired off the coast of Saudi Arabia near 22 °N. The tidal flow is found to be very weak. The strongest tidal constituent, the M2 tide, has a magnitude of order 4 cm s−1. Energetic near-inertial and diurnal period motions are observed. These are surface-intensified currents, reaching magnitudes of >10 cm s−1. Although the diurnal currents appear to be principally wind-driven, their relationship with the surface wind stress record is complex. Less than 50% of the diurnal current variance is related to the diurnal wind stress through linear correlation. Correlation analysis reveals a classical upwelling/downwelling response to the alongshore wind stress. However, less than 30% of the overall sub-inertial variance can be accounted for by this response. The action of basin-scale eddies, impinging on the coastal zone, is implicated as a primary mechanism for driving coastal flows.

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.

Mass-specific respiration of mesozooplankton and its role in the maintenance of an oxygen-deficient ecological barrier (BEDOX) in the upwelling zone off Chile upon presence of a shallow oxygen minimum zone

Science.gov (United States)

Donoso, Katty; Escribano, Ruben

2014-01-01

A shallow oxygen minimum zone (OMZ) in the coastal upwelling zone off Chile may vertically confine most zooplankton to a narrow (oxygen consumption of the mesozooplankton community obtained in Bay of Mejillones, northern Chile (23°S) in May 2010, December 2010 and August 2011. Mass-specific respiration rates were in the range of 8.2-24.5 μmol O2 mg dry mass- 1 day- 1, at an average temperature of 12 °C. Estimates of the mesozooplankton biomass in the water column indicated that its aerobic respiration may remove daily a maximum of about 20% of oxygen available at the base of the oxycline. Since previous work indicates that zooplankton aggregate near the base of the oxycline, the impact of aerobic respiration on oxygen content might be even stronger at this depth. Mesozooplankton respiration, along with community respiration by microorganisms near the base of the oxycline and a strongly stratified condition (limiting vertical flux of O2), are suggested as being critical factors causing and maintaining a persistent subsurface oxygen-deficient ecological barrier (BEDOX) in the upwelling zone. This BEDOX layer can have a major role in affecting and regulating zooplankton distribution and their dynamics in the highly productive coastal upwelling zone of the Humboldt Current System.

Dinoflagellate blooms in upwelling systems: Seeding, variability, and contrasts with diatom bloom behaviour

Science.gov (United States)

Smayda, T. J.; Trainer, V. L.

2010-04-01

The influence of diatom bloom behaviour, dinoflagellate life cycles, propagule type and upwelling bloom cycles on the seeding of dinoflagellate blooms in eastern boundary current upwelling systems is evaluated. Winter-spring diatom bloom behaviour is contrasted with upwelling bloom behaviour because their phenology impacts dinoflagellate blooms. The winter-spring diatom bloom is usually sustained, whereas the classical upwelling diatom bloom occurs as a series of separate, recurrent mini-blooms intercalated by upwelling-relaxation periods, during which dinoflagellates often bloom. Four sequential wind-regulated phases characterize upwelling cycles, with each phase having different effects on diatom and dinoflagellate bloom behaviour: bloom “spin up”, bloom maximum, bloom “spin down”, and upwelling relaxation. The spin up - bloom maximum is the period of heightened diatom growth; the spin down - upwelling-relaxation phases are the periods when dinoflagellates often bloom. The duration, intensity and ratio of the upwelling and relaxation periods making up upwelling cycles determine the potential for dinoflagellate blooms to develop within a given upwelling cycle and prior to the subsequent “spin up” of upwelling that favours diatom blooms. Upwelling diatoms and meroplanktonic dinoflagellates have three types of propagules available to seed blooms: vegetative cells, resting cells and resting cysts. However, most upwelling dinoflagellates are holoplanktonic, which indicates that the capacity to form resting cysts is not an absolute requirement for growth and survival in upwelling systems. The long-term (decadal) gaps in bloom behaviour of Gymnodinium catenatum and Lingulodinium polyedrum, and the unpredictable bloom behaviour of dinoflagellates generally, are examined from the perspective of seeding strategies. Mismatches between observed and expected in situ bloom behaviour and resting cyst dynamics are common among upwelling dinoflagellates. This

Tropical land-sea couplings: Role of watershed deforestation, mangrove estuary processing, and marine inputs on N fluxes in coastal Pacific Panama.

Science.gov (United States)

Valiela, Ivan; Elmstrom, Elizabeth; Lloret, Javier; Stone, Thomas; Camilli, Luis

2018-07-15

We review data from coastal Pacific Panama and other tropical coasts with two aims. First, we defined inputs and losses of nitrogen (N) mediating connectivity of watersheds, mangrove estuaries, and coastal sea. N entering watersheds-mainly via N fixation (79-86%)-was largely intercepted; N discharges to mangrove estuaries (3-6%), small compared to N inputs to watersheds, nonetheless significantly supplied N to mangrove estuaries. Inputs to mangrove estuaries (including watershed discharges, and marine inputs during flood tides) were matched by losses (mainly denitrification and export during ebb tides). Mangrove estuary subsidies of coastal marine food webs take place by export of forms of N [DON (62.5%), PN (9.1%), and litter N (12.9%)] that provide dissimilative and assimilative subsidies. N fixation, denitrification, and tidal exchanges were major processes, and DON was major form of N involved in connecting fluxes in and out of mangrove estuaries. Second, we assessed effects of watershed forest cover on connectivity. Decreased watershed forest cover lowered N inputs, interception, and discharge into receiving mangrove estuaries. These imprints of forest cover were erased during transit of N through estuaries, owing to internal N cycle transformations, and differences in relative area of watersheds and estuaries. Largest losses of N consisted of water transport of energy-rich compounds, particularly DON. N losses were similar in magnitude to N inputs from sea, calculated without considering contribution by intermittent coastal upwelling, and hence likely under-estimated. Pacific Panama mangrove estuaries are exposed to major inputs of N from land and sea, which emphasizes the high degree of bi-directional connectivity in these coupled ecosystems. Pacific Panama is still lightly affected by human or global changes. Increased deforestation can be expected, as well as changes in ENSO, which will surely raise watershed-derived loads of N, as well as significantly

Investigation of different coastal processes in Indonesian waters using SeaWiFS data

Science.gov (United States)

Hendiarti, Nani; Siegel, Herbert; Ohde, Thomas

2004-01-01

SeaWiFS data were applied to investigate coastal processes in Indonesian waters around the most populated island of Java. Coastal processes due to wind forcing were studied the first time using SeaWiFS-derived chlorophyll and TSM concentrations in combination with AVHRR-derived SST in the period from September 1997 to December 2001. Upwelling events were studied along the southern coast of Java during the southeast monsoon (June to September). Satellite-derived chlorophyll concentrations higher than 0.8 mg/ m3 and sea-surface temperatures lower than 28°C are indications of upwelling. Upwelling events influence the distribution and growth of phytoplankton and provide by that good feeding condition for zooplankton, larvae, juvenile and adult of pelagic fish. Coastal discharge into the western Java Sea contains organic and inorganic materials originating from different sources. Diffuse impacts, particularly from fish farms and aquaculture, as well as coastal erosion influence large coastal areas during the rainy season (December to March), and to a lesser extent during the dry season. Strong Citarum river discharge was observed during the transition phase from the rainy to the dry season (March and April), when the maximum amount of transported material reaches the sea. The river plume is evident from chlorophyll concentrations higher than 2.5 mg/ m3, and suspended particulate matter concentrations of more than 8 mg/dm3. The Sunda Strait is seasonally influenced by water transport from the Java Sea and from the Indian Ocean. The satellite data show that water transport from the Java Sea occurs during the pre-dominantly easterly winds period (June to September). This is characterized by warm water (SST higher than 29.5°C) and chlorophyll concentrations higher than 0.5 mg/ m3. This water transport influences the fish abundance in the Sunda Strait. High fish catches coincide with the presence of Java Sea water, while the surface currents lead to the migration of

Application of the Hyperspectral Imager for the Coastal Ocean to Phytoplankton Ecology Studies in Monterey Bay, CA, USA

Directory of Open Access Journals (Sweden)

John P. Ryan

2014-01-01

Full Text Available As a demonstrator for technologies for the next generation of ocean color sensors, the Hyperspectral Imager for the Coastal Ocean (HICO provides enhanced spatial and spectral resolution that is required to understand optically complex aquatic environments. In this study we apply HICO, along with satellite remote sensing and in situ observations, to studies of phytoplankton ecology in a dynamic coastal upwelling environment—Monterey Bay, CA, USA. From a spring 2011 study, we examine HICO-detected spatial patterns in phytoplankton optical properties along an environmental gradient defined by upwelling flow patterns and along a temporal gradient of upwelling intensification. From a fall 2011 study, we use HICO’s enhanced spatial and spectral resolution to distinguish a small-scale “red tide” bloom, and we examine bloom expansion and its supporting processes using other remote sensing and in situ data. From a spectacular HICO image of the Monterey Bay region acquired during fall of 2012, we present a suite of algorithm results for characterization of phytoplankton, and we examine the strengths, limitations, and distinctions of each algorithm in the context of the enhanced spatial and spectral resolution.

In hot water: the future of Australia's coastal and marine ecosystems

International Nuclear Information System (INIS)

Richardson, Anthony J; Poloczanska, Elvira

2007-01-01

Full text: Full text: Marine ecosystems are extremely important economically and ecologically to Australia in terms of tourism, coastal defence, resources, and ecosystem services such as nutrient cycling and waste disposal. Australia is also a globally important repository of biodiversity. Here we describe the observed and potential future impacts of climate change on Australia's marine diversity. Climate simulations project oceanic warming, an increase in stratification, a strengthening of the Eastern Australian Current, increased ocean acidification, a rise in sea level, and altered storm and rainfall regimes, which taken collectively will fundamentally change marine ecosystems. There has already been widespread bleaching of tropical corals, poleward shifts of temperate fish and plankton populations, and a decline in cold-water giant kelp off Tasmania. Future changes are likely to be even more dramatic and have considerable economic and ecological consequences, especially in 'hot spots' of climate change such as theTasman Sea and the Great Barrier Reef area. Corals are likely to bleach more frequently and decline in abundance in response to both warming and ocean acidification. Planktonic animals with calcium carbonate shells, such as winged pteropod snails and coccolithophorid phytoplankton, are likely to decline as increased ocean acidification impairs their ability to maintain carbonate body structures. The projected high warming off south-east Australia is of particular concern. Marine ecosystems in this region are already stressed by high metal concentrations, sewage pollution, and overfishing, and climate models project that this region will warm more than anywhere else in the Southern Hemisphere this century because of enhanced southerly penetration of the East Australian Current. Venomous jellyfish and harmful algal blooms, which are major threats to human health, will potentially extend further south and occur more frequently. Temperate species

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...

Degradation of mangroves adversely affected ecosystem and rural inhabitant in the Sindh's coastal area

International Nuclear Information System (INIS)

Naqvi, S.R.; Inam, Z.

2005-01-01

Mangroves the ecological treasure of Sindh, are facing a steady decline due to in active Government policies and lack of interest of local people. Mangroves provide important breeding Zone of to the marine biodiversity because of the reduction of silt flows, the area of active growth of delta, has been reduced from an original estimate of 2600 sq km to about 260 sq km. Similarly, the area of Mangroves from 345,000 hectares, the area is now only 205000 hectares. Pakistani Mangroves rank 6th among the mangroves spread in 92 countries. Mangroves forests act as inter face b/w land and sea. It provides nutrients to marine fisheries and is vital healthy Ecosystem. During past 50 years, nearly 100,000 hectares have been destroyed. The destruction is quite high from 1975 to 1992. It is due to water shortage in the river Indus. Degradation of mangroves adversely affected ecosystem and rural inhabitant in the coastal area. Thus to find root causes of degradation and its effects this study was made. (author)

Effluent Mixing Modeling for Liquefied Natural Gas Outfalls in a Coastal Ecosystem

Directory of Open Access Journals (Sweden)

Mustafa Samad

2014-06-01

Full Text Available Liquid Natural Gas (LNG processing facilities typically are located on ocean shores for easy transport of LNG by marine vessels. These plants use large quantities of water for various process streams. The combined wastewater effluents from the LNG plants are discharged to the coastal and marine environments typically through submarine outfalls. Proper disposal of effluents from an LNG plant is essential to retain local and regional environmental values and to ensure regulatory and permit compliance for industrial effluents. Typical outfall designs involve multi-port diffuser systems where the design forms a part of the overall environmental impact assessment for the plant. The design approach needs to ensure that both near-field plume dispersion and far-field effluent circulation meets the specified mixing zone criteria. This paper describes typical wastewater process streams from an LNG plant and presents a diffuser system design case study (for an undisclosed project location in a meso-tidal coast to meet the effluent mixing zone criteria. The outfall is located in a coastal and marine ecosystem where the large tidal range and persistent surface wind govern conditions for the diffuser design. Physical environmental attributes and permit compliance criteria are discussed in a generic format. The paper describes the design approach, conceptualization of numerical model schemes for near- and far-field effluent mixing zones, and the selected diffuser design.

How marine upwelling influences the distribution of Artemesia longinaris (Decapoda: Penaeoidea?

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Gustavo S Sancinetti

2014-05-01

Full Text Available Upwelling events can occur in most of the oceans altering the water physical, chemical and sediment conditions and consequently the species communities dwelling the areas. For better understanding the behavior of populations inhabiting upwelling regions, the spatial and temporal distribution of a Penaeoidea shrimp was studied correlating it with the abiotic factors that vary during upwelling and non-upwelling periods in an area under influence of Cabo Frio upwelling. Bottom salinity and temperature, organic matter and sediment type from each station were sampled from March 2008 to February 2010, in six stations located between 5 and 45 m depth. The lowest temperatures were recorded during spring and summer for both years with temperature values lower than 19ºC. A total of 26,466 Artemesia longinaris shrimps were captured mainly in 10-35 m depth. Upwelling periods showed significant differences in abundance in relation to non-upwelling periods. The spatial distribution among stations varied according to the temperature with higher abundance in stations with values between 19 and 21ºC. The highest abundance of A. longinaris was recorded in spring and summer when intrusions of the cold waters of South Atlantic Central Waters (SACW were frequent. Thus, the effect of cold water of SACW boosted by the upwelling was a determinant factor in the spatial and temporal distribution of A. longinaris in the studied region.

Nutrient variations and isotopic evidences of particulate organic matter provenance in fringing reefs, South China

International Nuclear Information System (INIS)

Cao, Di; Cao, Wenzhi; Liang, Ying; Huang, Zheng

2016-01-01

Nutrient over-enrichment is considered to be one of the causes of coral decline. Increase in traditional fishing in the Xuwen National Coral Reefs Reserve tract (XW) and tourism around the Sanya National Coral Reefs Reserve tract (SY) are causing this coral decline. This study reviews the current state of knowledge of the nutrient status of coastal fringing reefs in South China and evaluates the primary sources of nutrients using stable isotope method. Surveys of seawater nutrients showed that the seawater remained clean in both the XW and SY coastal coral reef areas. Based on the isotopic differences between anthropogenic sewage and naturally occurring aquatic nutrients, the isotopic values of particulate organic matter (POM) and the C/N ratios were successfully used to identify the presence of anthropogenic nutrients in aquatic environments. The δ"1"3C, δ"1"5N and C/N compositions of POM from XW and SY (− 21.18 ± 2.11‰, 10.30 ± 5.54‰, and 5.35 ± 0.69 and − 20.80 ± 1.34‰, 7.06 ± 3.95‰, and 5.77 ± 2.15, respectively) showed statistically significant variations with the season. The δ"1"3C and δ"1"5N values of POM suggest marine and terrestrial-derived nutrient sources. Organic carbon is a mixture of marine phytoplankton, marine benthic algae and terrestrial-derived plants. The δ"1"5N values suggest terrestrial-derived sewage and upwelling-dominated nitrogen sources. In the presence of natural upwelling and coastal currents, coastal coral reef areas are more vulnerable to the increasing anthropogenic nutrient inputs. Anthropogenic activities might lead to large increases in the nutrient concentrations and could trigger the shift from coral- to macroalgae-dominated ecosystems, which would ultimately result in the degradation of the coastal coral reef ecosystem. These results provide some understanding of the declining coral reef ecosystem and the importance of conservation areas and coastal coral reef resource management. - Highlights: • The

Nutrient variations and isotopic evidences of particulate organic matter provenance in fringing reefs, South China

Energy Technology Data Exchange (ETDEWEB)

Cao, Di; Cao, Wenzhi, E-mail: wzcao@xmu.edu.cn; Liang, Ying; Huang, Zheng

2016-10-01

Nutrient over-enrichment is considered to be one of the causes of coral decline. Increase in traditional fishing in the Xuwen National Coral Reefs Reserve tract (XW) and tourism around the Sanya National Coral Reefs Reserve tract (SY) are causing this coral decline. This study reviews the current state of knowledge of the nutrient status of coastal fringing reefs in South China and evaluates the primary sources of nutrients using stable isotope method. Surveys of seawater nutrients showed that the seawater remained clean in both the XW and SY coastal coral reef areas. Based on the isotopic differences between anthropogenic sewage and naturally occurring aquatic nutrients, the isotopic values of particulate organic matter (POM) and the C/N ratios were successfully used to identify the presence of anthropogenic nutrients in aquatic environments. The δ{sup 13}C, δ{sup 15}N and C/N compositions of POM from XW and SY (− 21.18 ± 2.11‰, 10.30 ± 5.54‰, and 5.35 ± 0.69 and − 20.80 ± 1.34‰, 7.06 ± 3.95‰, and 5.77 ± 2.15, respectively) showed statistically significant variations with the season. The δ{sup 13}C and δ{sup 15}N values of POM suggest marine and terrestrial-derived nutrient sources. Organic carbon is a mixture of marine phytoplankton, marine benthic algae and terrestrial-derived plants. The δ{sup 15}N values suggest terrestrial-derived sewage and upwelling-dominated nitrogen sources. In the presence of natural upwelling and coastal currents, coastal coral reef areas are more vulnerable to the increasing anthropogenic nutrient inputs. Anthropogenic activities might lead to large increases in the nutrient concentrations and could trigger the shift from coral- to macroalgae-dominated ecosystems, which would ultimately result in the degradation of the coastal coral reef ecosystem. These results provide some understanding of the declining coral reef ecosystem and the importance of conservation areas and coastal coral reef resource management

The Triassic upwelling system of Arctic Alaska

Science.gov (United States)

Yurchenko, I.; Graham, S. A.

2017-12-01

The Middle to Upper Triassic Shublik Formation of Arctic Alaska is a laterally and vertically heterogeneous rock unit that has been analyzed both in outcrop and in the subsurface. The Shublik Formation sediments are distinguished by a characteristic set of lithologies that include glauconitic, phosphatic, organic-rich, and cherty facies consistent with a coastal upwelling zone deposition interpretation. It is often recognized by abundance of impressions and shells of distinctive Triassic bivalves. To understand main controls on lithofacies distributions, this study reviews and refines lithologic and paleoenvironmental interpretations of the Shublik Formation, and incorporates the newly acquired detailed geochemical analyses of two complete Shublik cores. This work focuses on organic geochemistry (analyses of biomarkers and diamondoids), chemostratigraphy (hand-held XRF), and iron speciation analysis to reconstruct paleoproductivity and redox conditions. Based on the available evidence, during Shublik deposition, an upwelling-influenced open shelf resulted in high nutrient supply that stimulated algal blooms leading to high net organic productivity, reduced water transparency, oxygen deficiency, and water column stratification. Evidence of such eutrophic conditions is indicated by the lack of photic benthic organisms, bioturbation and trace fossils, and dominance of the monospecific light-independent epibenthic bivalves. The flat, subcircular, thin shells of these carbonate-secreting organisms allowed them to adapt to dysoxic conditions, and float on soft, soupy, muddy substrate. The distinctive clay- and organic-rich facies with abundant bivalves occurred on the mid to outer stable broad shelf, and were deposited when organic productivity at times overlapped with periods of increased siliciclastic input controlled by sea level and changes in local sediment dispersal systems, and therefore are more spatially and temporally localized than the widespread clay

Large Plankton Enhance Heterotrophy Under Experimental Warming in a Temperate Coastal Ecosystem

KAUST Repository

Huete-Stauffer, Tamara Megan

2017-12-15

Microbes are key players in oceanic carbon fluxes. Temperate ecosystems are seasonally variable and thus suitable for testing the effect of warming on microbial carbon fluxes at contrasting oceanographic conditions. In four experiments conducted in February, April, August and October 2013 in coastal NE Atlantic waters, we monitored microbial plankton stocks and daily rates of primary production, bacterial heterotrophic production and respiration at in situ temperature and at 2 and 4°C over ambient values during 4-day incubations. Ambient total primary production (TPP) exceeded total community respiration (< 200 µm, TR) in winter and fall but not in spring and summer. The bacterial contribution to ecosystem carbon fluxes was low, with bacterial production representing on average 6.9 ± 3.2% of TPP and bacterial respiration (between 0.8 and 0.2 µm) contributing on average 35 ± 7% to TR. Warming did not result in a uniform increase in the variables considered, and most significant effects were found only for the 4°C increase. In the summer and fall experiments, under warm and nutrient-deficient conditions, the net TPP/TR ratio decreased by 39 and 34% in the 4°C treatment, mainly due to the increase in respiration of large organisms rather than bacteria. Our results indicate that the interaction of temperature and substrate availability in determining microbial carbon fluxes has a strong seasonal component in temperate planktonic ecosystems, with temperature having a more pronounced effect and generating a shift toward net heterotrophy under more oligotrophic conditions as found in summer and early fall.

Short commentary on marine productivity at Arctic shelf breaks: upwelling, advection and vertical mixing

Directory of Open Access Journals (Sweden)

A. Randelhoff

2018-04-01

Full Text Available The future of Arctic marine ecosystems has received increasing attention in recent years as the extent of the sea ice cover is dwindling. Although the Pacific and Atlantic inflows both import huge quantities of nutrients and plankton, they feed into the Arctic Ocean in quite diverse regions. The strongly stratified Pacific sector has a historically heavy ice cover, a shallow shelf and dominant upwelling-favourable winds, while the Atlantic sector is weakly stratified, with a dynamic ice edge and a complex bathymetry. We argue that shelf break upwelling is likely not a universal but rather a regional, albeit recurring, feature of the new Arctic. It is the regional oceanography that decides its importance through a range of diverse factors such as stratification, bathymetry and wind forcing. Teasing apart their individual contributions in different regions can only be achieved by spatially resolved time series and dedicated modelling efforts. The Northern Barents Sea shelf is an example of a region where shelf break upwelling likely does not play a dominant role, in contrast to the shallower shelves north of Alaska where ample evidence for its importance has already accumulated. Still, other factors can contribute to marked future increases in biological productivity along the Arctic shelf break. A warming inflow of nutrient-rich Atlantic Water feeds plankton at the same time as it melts the sea ice, permitting increased photosynthesis. Concurrent changes in sea ice cover and zooplankton communities advected with the boundary currents make for a complex mosaic of regulating factors that do not allow for Arctic-wide generalizations.

Short commentary on marine productivity at Arctic shelf breaks: upwelling, advection and vertical mixing

Science.gov (United States)

Randelhoff, Achim; Sundfjord, Arild

2018-04-01

The future of Arctic marine ecosystems has received increasing attention in recent years as the extent of the sea ice cover is dwindling. Although the Pacific and Atlantic inflows both import huge quantities of nutrients and plankton, they feed into the Arctic Ocean in quite diverse regions. The strongly stratified Pacific sector has a historically heavy ice cover, a shallow shelf and dominant upwelling-favourable winds, while the Atlantic sector is weakly stratified, with a dynamic ice edge and a complex bathymetry. We argue that shelf break upwelling is likely not a universal but rather a regional, albeit recurring, feature of the new Arctic. It is the regional oceanography that decides its importance through a range of diverse factors such as stratification, bathymetry and wind forcing. Teasing apart their individual contributions in different regions can only be achieved by spatially resolved time series and dedicated modelling efforts. The Northern Barents Sea shelf is an example of a region where shelf break upwelling likely does not play a dominant role, in contrast to the shallower shelves north of Alaska where ample evidence for its importance has already accumulated. Still, other factors can contribute to marked future increases in biological productivity along the Arctic shelf break. A warming inflow of nutrient-rich Atlantic Water feeds plankton at the same time as it melts the sea ice, permitting increased photosynthesis. Concurrent changes in sea ice cover and zooplankton communities advected with the boundary currents make for a complex mosaic of regulating factors that do not allow for Arctic-wide generalizations.

DNA metabarcoding reveals diverse diet of the three-spined stickleback in a coastal ecosystem.

Directory of Open Access Journals (Sweden)

Eglė Jakubavičiūtė

Full Text Available The three-spined stickleback (Gasterosteus aculeatus L., hereafter 'stickleback' is a common mesopredatory fish in marine, coastal and freshwater areas. In large parts of the Baltic Sea, stickleback densities have increased >10-fold during the last decades, and it is now one of the dominating fish species both in terms of biomass and effects on lower trophic levels. Still, relatively little is known about its diet-knowledge which is essential to understand the increasing role sticklebacks play in the ecosystem. Fish diet analyses typically rely on visual identification of stomach contents, a labour-intensive method that is made difficult by prey digestion and requires expert taxonomic knowledge. However, advances in DNA-based metabarcoding methods promise a simultaneous identification of most prey items, even from semi-digested tissue. Here, we studied the diet of stickleback from the western Baltic Sea coast using both DNA metabarcoding and visual analysis of stomach contents. Using the cytochrome oxidase (CO1 marker we identified 120 prey taxa in the diet, belonging to 15 phyla, 83 genera and 84 species. Compared to previous studies, this is an unusually high prey diversity. Chironomids, cladocerans and harpacticoids were dominating prey items. Large sticklebacks were found to feed more on benthic prey, such as amphipods, gastropods and isopods. DNA metabarcoding gave much higher taxonomic resolution (median rank genus than visual analysis (median rank order, and many taxa identified using barcoding could not have been identified visually. However, a few taxa identified by visual inspection were not revealed by barcoding. In summary, our results suggest that the three-spined stickleback feeds on a wide variety of both pelagic and benthic organisms, indicating that the strong increase in stickleback populations may affect many parts of the Baltic Sea coastal ecosystem.

Use of fish parasite species richness indices in analyzing anthropogenically impacted coastal marine ecosystems

Science.gov (United States)

Dzikowski, R.; Paperna, I.; Diamant, A.

2003-10-01

The diversity of fish parasite life history strategies makes these species sensitive bioindicators of aquatic ecosystem health. While monoxenous (single-host) species may persist in highly perturbed, extreme environments, this is not necessarily true for heteroxenous (multiple-host) species. As many parasites possess complex life cycles and are transmitted through a chain of host species, their dependency on the latter to complete their life cycles renders them sensitive to perturbed environments. In the present study, parasite communities of grey mullet Liza aurata and Liza ramada (Mugilidae) were investigated at two Mediterranean coastal sites in northern Israel: the highly polluted Kishon Harbor (KH) and the relatively unspoiled reference site, Ma'agan Michael (MM). Both are estuarine sites in which grey mullet are one of the most common fish species. The results indicate that fish at the polluted site had significantly less trematode metacercariae than fish at the reference site. Heteroxenous gut helminths were completely absent at the polluted sampling site. Consequently, KH fish displayed lower mean parasite species richness. At the same time, KH fish mean monoxenous parasite richness was higher, although the prevalence of different monoxenous taxa was variable. Copepods had an increased prevalence while monogenean prevalence was significantly reduced at the polluted site. This variability may be attributed to the differential susceptibility of the parasites to the toxicity of different pollutants, their concentration, the exposure time and possible synergistic effects. In this study, we used the cumulative species curve model that extrapolates "true" species richness of a given habitat as a function of increasing sample size. We considered the heteroxenous and monoxenous species separately for each site, and comparison of curves yielded significant results. It is proposed to employ this approach, originally developed for estimating the "true" parasite

Coastal upwelling ecosystems are known to be parts of the most ...

African Journals Online (AJOL)

spamer

very high rate of primary production, but they are ... However, in areas such as Peru, Senegal and Côte ... mixed layer off Peru in winter is taken into account, the speed of surface ..... Fish Resources, San José, Costa Rica, April 1983. Sharp,.

Preface: Biogeochemistry–ecosystem interaction on changing continental margins in the Anthropocene

Digital Repository Service at National Institute of Oceanography (India)

Liu, K-K.; Emeis, K.-C.; Levin, L.A.; Naqvi, S.W.A.; Roman, M.

and hypercapnia in upwelling systems • Interactions between natural and social sciences for better steward- ship of continental margins. It has long been acknowledged (e.g., Doney, 2010; Liu et al., 2010) that marine ecosystems on continental margins, including... and possibly manage margin ecosystems in a changing world. Effective governance of social–ecological systems on continental margins is key to reducing the pervasive over- exploitation, depletion and destruction of marine resources and http://dx.doi.org/10...

Managing coastal resources in the 21st century

NARCIS (Netherlands)

Weinstein, Michael P.; Baird, Ronald C.; Conover, David O.; Gross, Matthias; Keulartz, Jozef; Loomis, David K.; Naveh, Zev; Peterson, Susan B.; Reed, Denise J.; Roe, Emery; Swanson, R. Lawrence; Swart, Jacques A. A.; Teal, John M.; Turner, R. Eugene; van der Windt, Henny J.

Coastal ecosystems are increasingly dominated by humans. Consequently, the human dimensions of sustainability science have become an integral part of emerging coastal governance and management practices. But if we are to avoid the harsh lessons of land management, coastal decision makers must

Radiolarian Indices of Paleoproductivity Variation in the late Pleistocene Benguela Upwelling System, ODP Site 1084

Science.gov (United States)

Bittniok, B. B.; Lazarus, D. B.; Diester-Haass, L.; Billups, K.; Meyers, P.

2006-12-01

Changes in export productivity play a significant role in ocean carbon budgets and global climate change. Proxies for export productivity can be difficult to interpret: benthic foraminifera accumulation rates (BFAR) can be affected by carbonate dissolution in organic-carbon rich sediments; bulk opal can be affected by silica limitation of source waters. Recent work (Lazarus et al. 2006; Mar. Micropal.) has shown that a new index based on radiolarian faunal changes (WADE ratio) correlates well to total organic carbon (TOC) values from the same samples over the long term (latest Miocene-Recent) history of productivity in the Benguela Upwelling System (BUS). We present new data on variation in export productivity proxies (WADE, TOC, carbonate, radiolarian opal, BFAR) for the last glacial-interglacial cycle from ODP Site 1084, located just offshore from the main coastal upwelling cells of the BUS. Our age model, from mean Quaternary sedimentation rates (Leg 175 Scientific Results), is in accordance with cyclic variation in other climate sensitive parameters (carbonate and color reflectance). Although opal content and radiolarian preservation is only moderate in our samples, WADE values vary significantly and suggest higher productivity during the last glacial, in accordance with current interpretations of BUS history. Radiolarian opal accumulation is also higher during the last glacial, suggesting that silica limitation (opal paradox) conditions did not dominate over this time period. Similar results for bulk opal have been reported from late Quaternary piston cores from the more northerly Congo upwelling region (Schneider et al, 1997; Paleoc.). We conclude that WADE ratios are a useful proxy for late Pleistocene productivity in the BUS at glacial- interglacial time scales.

Coastal remote sensing – towards integrated coastal research and management

CSIR Research Space (South Africa)

Lück-Vogel, Melanie

2012-10-01

Full Text Available coastal resources and anthropogenic infrastructure for a safer future. What is the role of remote sensing? The coastal zone connects terrestrial biophysical systems with marine systems. Some marine ecosystems cannot function without intact inland... for the development of sound integrated management solutions. To date, however, remote sensing applications usually focus on areas landward from the highwater line (?terrestrial? remote sensing), while ?marine? remote sensing does not pay attention to the shallow...

Changes in the coastal and marine environments

Digital Repository Service at National Institute of Oceanography (India)

DeSousa, S.N.; Ahmed, A.U.; DileepKumar, M.; Jagtap, T.G.; Sardessai, S.; Hassan, A.

to the euphotic layer. These factors make the Arabian Sea a potentially fertile area, since any vertical disturbance that can disrupt or shift the thermocline banier can lead to injection of nutrients into the euphotic layer and fuel increased biological...) injecting nutrients from the thermocline region into the surface layer, as observed by de Sousa et a!. (1996b). 1.1.3 Biological Response It was seen in sections 1.1.1-1.1.2 that processes of upwelling (both coastal and open ocean) during summer monsoon...

Aquaculture in mangrove ecosystems of India: State of art and prospects

Digital Repository Service at National Institute of Oceanography (India)

Parulekar, A.H.

The mangrove vegetation spread over 0.35 million hactares accounts for less than 1/10th of the extensive coastal ecosystems of India. It's an experience that the coastal ecosystems which are intricately diverse are equally high productive biotopes...

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.

The need for ecosystem-based coastal planning in Trabzon city

OpenAIRE

Dikhan, Mustafa; Güneroğlu, Nilgün; Güneroğlu, Abdülaziz; Karslı, Fevzi

2017-01-01

Coastalurbanization problem was emanated from willingness of coastal living. Urbansprawl is one of the most important coastal problems in Turkey as it is inTrabzon city which is known for its natural and historical assets. In order toensure the sustainability and ecological continuity of the city, an ecosystembased coastal planning is an issue of high priority. Protection and usagebalance of the coastal areas could also ensure transition of the natural valuesto future generations. Trabzon cit...

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.

Models for ecological models: Ocean primary productivity

Science.gov (United States)

Wikle, Christopher K.; Leeds, William B.; Hooten, Mevin B.

2016-01-01

The ocean accounts for more than 70% of planet Earth's surface, and it processes are critically important to marine and terrestrial life.  Ocean ecosystems are strongly dependent on the physical state of the ocean (e.g., transports, mixing, upwelling, runoff, and ice dynamics(.  As an example, consider the Coastal Gulf of Alaska (CGOA) region.

A marine eutrophication impacts assessment method in LCIA coupling coastal ecosystems exposure to nitrogen and species sensitivity to hypoxia

DEFF Research Database (Denmark)

Cosme, Nuno Miguel Dias; Koski, Marja; Hauschild, Michael Zwicky

Characterisation modelling in Life Cycle Impact Assessment (LCIA) aims at quantifying potential impacts of anthropogenic emissions. It delivers substance-specific Characterisation Factors (CF) expressing ecosystem responses to marginal increments in emitted quantities. Nitrogen (N) emissions from e.......g. agriculture and industry enrich coastal marine ecosystems. Excessive algal growth and dissolved oxygen (DO) depletion typify the resulting marine eutrophication. LCIA modelling frameworks typically encompass fate, exposure and effect in the environment. The present novel method couples relevant marine...... biological processes of ecosystem’s N exposure (Exposure Factor, XF) with the sensitivity of select species to hypoxia (Effect Factor, EF). The XF converts N-inputs into a sinking carbon flux from planktonic primary production and DO consumed by bacterial respiration in bottom waters, whereas EF builds...

The sustainable use of tropical coastal resources - A key conservation issue

Energy Technology Data Exchange (ETDEWEB)

Holdgate, M W [IUCN-World Conservation Union, Gland (Switzerland)

1993-01-01

The three papers covered in this review form a series, addressing broadly the same issues in increasing detail. The paper by Carl Gustaf Lundin and Olof Linden, on 'Coastal ecosystems: Attempts to manage a threatened resource', takes a wide view of the coastal zones (the regions between the seaward margins of the continental shelves, in water depths of around 200 m and the landward edge of the coastal plains at a comparable altitude above mean sea level), and the nature of the pressures upon them. The paper by Magnus A.K. Ngoile and Chris J. Horrill, on 'Coastal ecosystems productivity and ecosystem protection: Coastal ecosystem management', focuses very much on these same issues of use and pressure in the Eastern Africa Region. The paper by M.C.Oehman, A. Rajasuriya and O. Linden, on 'Human disturbances on coral reefs in Sri Lanka: A case study' looks in some depth at the situation on three selected reef systems in the one country. All the papers address the key question of how the management of coastal resources should change, in order to avoid continuing degradation and the cost and impoverishment it is likely to bring. The three papers mentioned is published in this issue of Ambio, p. 461-480

Wind-driven coastal upwelling along the western boundary of the Bay of Bengal during the southwest monsoon

Digital Repository Service at National Institute of Oceanography (India)

Shetye, S.R.; Shenoi, S.S.C.; Gouveia, A.D.; Michael, G.S.; Sundar, D.; Nampoothiri, G.

The western boundary regions of the world's oceans generally show the influence of remote forcing by the presence of a western boundary current. On the continental shelf off Florida, U.S.A., influence of the Gulf Stream is felt at locations as shallow as 75... upwelling on the Bay of Bengal 1403 ee" ~t 32 i i* Fig. 6. bo" , e.5, , , to" Salinity (ppt) at the surface. Dots indicate station locations. using available climatologies. The charts for 10-day mean ship-drift averaged over 1 ° x 1 ° given...

A model study of the seasonality of sea surface temperature and circulation in the Atlantic North-Eastern Tropical Upwelling System.

Directory of Open Access Journals (Sweden)

Saliou eFaye

2015-09-01

Full Text Available The climatological seasonal cycle of the sea surface temperature (SST in the north-eastern tropical Atlantic (7-25°N, 26-12°W is studied using a mixed layer heat budget in a regional ocean general circulation model. The region, which experiences one of the larger SST cycle in the tropics, forms the main part of the Guinea Gyre. It is characterized by a seasonally varying open ocean and coastal upwelling system, driven by the movements of the intertropical convergence zone (ITCZ. The model annual mean heat budget has two regimes schematically. South of roughly 12°N, advection of equatorial waters, mostly warm, and warming by vertical mixing, is balanced by net air-sea flux. In the rest of the domain, a cooling by vertical mixing, reinforced by advection at the coast, is balanced by the air-sea fluxes. Regarding the seasonal cycle, within a narrow continental band, in zonal mean, the SST early decrease (from September, depending on latitude, until December is driven by upwelling dynamics off Senegal and Mauritania (15°-20°N, and instead by air-sea fluxes north and south of these latitudes. Paradoxically, the later peaks of upwelling intensity (from March to July, with increasing latitude essentially damp the warming phase, driven by air-sea fluxes. The open ocean cycle to the west, is entirely driven by the seasonal net air-sea fluxes. The oceanic processes significantly oppose it, but for winter north of ~18°N. Vertical mixing in summer-autumn tends to cool (warm the surface north (south of the ITCZ, and advective cooling or warming by the geostrophic Guinea Gyre currents and the Ekman drift. This analysis supports previous findings on the importance of air-sea fluxes offshore. It mainly offers quantitative elements on the modulation of the SST seasonal cycle by the ocean circulation, and particularly by the upwelling dynamics.Keywords: SST, upwelling, circulation, heat budget, observations, modeling

Introducing mixotrophy into a biogeochemical model describing an eutrophied coastal ecosystem: The Southern North Sea

Science.gov (United States)

Ghyoot, Caroline; Lancelot, Christiane; Flynn, Kevin J.; Mitra, Aditee; Gypens, Nathalie

2017-09-01

Most biogeochemical/ecological models divide planktonic protists between phototrophs (phytoplankton) and heterotrophs (zooplankton). However, a large number of planktonic protists are able to combine several mechanisms of carbon and nutrient acquisition. Not representing these multiple mechanisms in biogeochemical/ecological models describing eutrophied coastal ecosystems can potentially lead to different conclusions regarding ecosystem functioning, especially regarding the success of harmful algae, which are often reported as mixotrophic. This modelling study investigates the implications for trophic dynamics of including 3 contrasting forms of mixotrophy, namely osmotrophy (using alkaline phosphatase activity, APA), non-constitutive mixotrophy (acquired phototrophy by microzooplankton) and also constitutive mixotrophy. The application is in the Southern North Sea, an ecosystem that faced, between 1985 and 2005, a significant increase in the nutrient supply N:P ratio (from 31 to 81 mol N:P). The comparison with a traditional model shows that, when the winter N:P ratio in the Southern North Sea is above 22 molN molP-1 (as occurred from mid-1990s), APA allows a 3-32% increase of annual gross primary production (GPP). In result of the higher GPP, the annual sedimentation increases as well as the bacterial production. By contrast, APA does not affect the export of matter to higher trophic levels because the increased GPP is mainly due to Phaeocystis colonies, which are not grazed by copepods. Under high irradiance, non-constitutive mixotrophy appreciably increases annual GPP, transfer to higher trophic levels, sedimentation, and nutrient remineralisation. In this ecosystem, non-constitutive mixotrophy is also observed to have an indirect stimulating effect on diatoms. Constitutive mixotrophy in nanoflagellates appears to have little influence on this ecosystem functioning. An important conclusion from this work is that contrasting forms of mixotrophy have different

Satellite Sensor Requirements for Monitoring Essential Biodiversity Variables of Coastal Ecosystems

Science.gov (United States)

Muller-Karger, Frank E.; Hestir, Erin; Ade, Christiana; Turpie, Kevin; Roberts, Dar A.; Siegel, David; Miller, Robert J.; Humm, David; Izenberg, Noam; Keller, Mary;

Spatial distribution of common Minke whale (Balaenoptera acutorostrata) as an indication of a biological hotspot in the East Sea

Science.gov (United States)

Lee, Dasom; An, Yong Rock; Park, Kyum Joon; Kim, Hyun Woo; Lee, Dabin; Joo, Hui Tae; Oh, Young Geun; Kim, Su Min; Kang, Chang Keun; Lee, Sang Heon

2017-09-01

The minke whale (Balaenoptera acutorostrata) is the most common baleen whale among several marine mammal species observed in Korea. Since a high concentrated condition of prey to whales can be obtained by physical structures, the foraging whale distribution can be an indicator of biological hotspot. Our main objective is verifying the coastal upwelling-southwestern East Sea as a productive biological hotspot based on the geographical distribution of minke whales. Among the cetacean research surveys of the National Institute of Fisheries Science since 1999, 9 years data for the minke whales available in the East Sea were used for this study. The regional primary productivity derived from Moderate-Resolution Imaging Spectroradiometer (MODIS) was used for a proxy of biological productivity. Minke whales observed during the sighting surveys were mostly concentrated in May and found mostly (approximately 70%) in the southwestern coastal areas (whales was found in recent years, which indicate that the major habitats of mink whales have been shifted into the north of the common coastal upwelling regions. This is consistent with the recently reported unprecedented coastal upwelling in the mid-eastern coast of Korea. Based on high phytoplankton productivity and high distribution of minke whales, the southwestern coastal regions can be considered as one of biological hotspots in the East Sea. These regions are important for ecosystem dynamics and the population biology of top marine predators, especially migratory whales and needed to be carefully managed from a resource management perspective.

Coastal Innovation Imperative

Directory of Open Access Journals (Sweden)

Bruce C. Glavovic

2013-03-01

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

Kinetics of N-Utilization By Natural Phytoplankton Assemblages During Upwelling Events At The NW Iberian Shelf

Science.gov (United States)

Brion, N.; Elskens, M.; Dehairs, F.; Baeyens, W.

2003-04-01

, nitrate uptake rate was dominant resulting in f-ratio values greater than 0.5, a characteristic of a new production regime. The new production rate is only marginally sensitive to increases of the ambient nitrate, but is drastically inhibited by small increases of the ambient ammonium. The situation of September 1999 was very close to that observed in July 1998, with higher nitrate concentrations in the coastal northern part of the sampling area dominated by upwelling.

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.

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

Differential responses of calcifying and non-calcifying epibionts of a brown macroalga to present-day and future upwelling pCO2.

Directory of Open Access Journals (Sweden)

Vincent Saderne

Full Text Available Seaweeds are key species of the Baltic Sea benthic ecosystems. They are the substratum of numerous fouling epibionts like bryozoans and tubeworms. Several of these epibionts bear calcified structures and could be impacted by the high pCO2 events of the late summer upwellings in the Baltic nearshores. Those events are expected to increase in strength and duration with global change and ocean acidification. If calcifying epibionts are impacted by transient acidification as driven by upwelling events, their increasing prevalence could cause a shift of the fouling communities toward fleshy species. The aim of the present study was to test the sensitivity of selected seaweed macrofoulers to transient elevation of pCO2 in their natural microenvironment, i.e. the boundary layer covering the thallus surface of brown seaweeds. Fragments of the macroalga Fucus serratus bearing an epibiotic community composed of the calcifiers Spirorbis spirorbis (Annelida and Electra pilosa (Bryozoa and the non-calcifier Alcyonidium hirsutum (Bryozoa were maintained for 30 days under three pCO2 conditions: natural 460 ± 59 µatm, present-day upwelling1193 ± 166 µatm and future upwelling 3150 ± 446 µatm. Only the highest pCO2 caused a significant reduction of growth rates and settlement of S. spirorbis individuals. Additionally, S. spirorbis settled juveniles exhibited enhanced calcification of 40% during daylight hours compared to dark hours, possibly reflecting a day-night alternation of an acidification-modulating effect by algal photosynthesis as opposed to an acidification-enhancing effect of algal respiration. E. pilosa colonies showed significantly increased growth rates at intermediate pCO2 (1193 µatm but no response to higher pCO2. No effect of acidification on A. hirsutum colonies growth rates was observed. The results suggest a remarkable resistance of the algal macro-epibionts to levels of acidification occurring at present day upwellings in the Baltic

Octopus vulgaris paralarvae vertical distribution in a fluctuating upwelling-downwelling system

Directory of Open Access Journals (Sweden)

Lorena Olmos Pérez

2014-06-01

- Upwelling situation: superficial waters (0-20m enter through the northern mouth of the Ría and are washed through the southern mouth. This water movement promotes the entrance of cold, bottom upwelled water through the southern mouth of the Ría. Under this scenario, Octopus paralarvae are concentrated at the surface (10-0m, thus leaving the Ría. This difference is bigger after strong upwelling during the previous days. Abundances inside the Ría are the highest, maybe because it acts as a temporal retention area, or because cold upwelled waters might stimulate hatching inside the Ría. Day/night changes under strong upwelling conditions: paralarvae abundance in both mouths was quite similar, except that during the day they were in sub-surficial waters (10-5 m, while at night paralarvae were mainly found close to the surface (0-5 m. This vertical distribution during the day is remarkable because paralarvae may select offward surface waters.

Environmental controls on the carbon isotope composition of ecosystem-respired CO{sub 2} in contrasting forest ecosystems in Canada and the USA

Energy Technology Data Exchange (ETDEWEB)

Alstad, K.P. [Lethbridge Univ., Lethbridge, AB (Canada). Dept. of Biological Sciences; Toledo Univ., Toledo, OH (United States). Dept. of Environmental Sciences; Flanagan, L.B. [Lethbridge Univ., Lethbridge, AB (Canada). Dept. of Biological Sciences; Lai, C.T. [Utah Univ., Salt Lake City, UT (United States); San Diego State Univ., San Diego, CA (United States); Ehleringer, J.R. [Utah Univ., Salt Lake City, UT (United States)

2007-10-15

Eleven forest ecosystems in Canada and the United States were compared in order to test for differences among forest {delta}{sup 13} carbon (C) responses to seasonal variations in environmental conditions from May to October 2004. Carbon isotope composition of ecosystem-respired carbon dioxide (CO{sub 2}) was considered as a proxy for short-term changes in photosynthetic discrimination. The study compared coniferous and deciduous forests, as well as forests in boreal and coastal environments. It was hypothesized that the carbon isotope composition of ecosystem-respired CO{sub 2} varied in a manner consistent with results obtained in leaf-level studies. Results of the study showed that higher R{sup 2} values were obtained for coastal ecosystems. The relationships between {delta}{sup 13}C{sub R} and environmental conditions were consistent with results obtained from leaf-level studies. Vapour pressure deficits and soil temperatures were significant determinants of variations in {delta}{sup 13}C{sub R} in the boreal forest ecosystem. Variations in {delta}{sup 13}C{sub R} in the coastal forest ecosystem correlated with changes in photosynthetic photon flux (PPF). It was concluded that {delta}{sup 13}C{sub R} measurements can be used to assess yearly variations in ecosystem physiological responses to changing environmental conditions. 59 refs., 7 tabs., 6 figs.

Climate variability and El Niño Southern Oscillation: implications for natural coastal resources and management

Science.gov (United States)

Thatje, Sven; Heilmayer, Olaf; Laudien, Jürgen

2008-03-01

The El Niño Southern Oscillation (ENSO) significantly influences marine ecosystems and the sustained exploitation of marine resources in the coastal zone of the Humboldt Current upwelling system. Both its warm (El Niño: EN) and cold (La Niña: LN) phase have drastic implications for the ecology, socio-economy and infrastructure along most of Pacific South America. Local artisanal fisheries, which especially suffer from the effects of EN, represent a major part for the domestic economy of Chile and Peru and in consequence a huge amount of published and unpublished studies exists aiming at identifying effects of EN and LN. However, most processes and underlying mechanisms fostering the ecology of organisms along Pacific South America have not been analyzed yet and for the marine realm most knowledge is traditionally based on rather descriptive approaches. We herein advocate that small-scale comparative and interdisciplinary process studies work as one possible solution to understand better the variability observed in EN/LN effects at local scale. We propose that differences in small-scale impacts of ENSO along the coast rather than the macro-ecological and oceanographic view are essential for the sustainable management of costal ecosystems and the livelihood of the people depending on it. Based on this, we summarize the conceptual approach from the EU-funded International Science and Technology Cooperation (INCO) project “Climate variability and El Niño Southern Oscillation: Implications for Natural Coastal Resources and Management (CENSOR)” that aims at enhancing the detection, compilation, and understanding of EN and LN effects on the coastal zone and its natural resources. We promote a multidisciplinary avenue within present international funding schemes, with the intention to bridge the traditional gap between basic and applied coastal research. The long-term aim is an increased mitigation of harm caused by EN as well as a better use of beneficial effects

Historical and contemporary imagery to assess ecosystem change on the Arctic coastal plain of northern Alaska

Science.gov (United States)

Tape, Ken D.; Pearce, John M.; Walworth, Dennis; Meixell, Brandt W.; Fondell, Tom F.; Gustine, David D.; Flint, Paul L.; Hupp, Jerry W.; Schmutz, Joel A.; Ward, David H.

2014-01-01

The Arctic Coastal Plain of northern Alaska is a complex landscape of lakes, streams, and wetlands scattered across low-relief tundra that is underlain by permafrost. This region of the Arctic has experienced a warming trend over the past three decades leading to thawing of on-shore permafrost and the disappearance of sea ice at unprecedented rates. The U.S. Geological Survey’s (USGS) Changing Arctic Ecosystems (CAE) research initiative was developed to investigate and forecast these rapid changes in the physical environment of the Arctic, and the associated changes to wildlife populations, in order to inform key management decisions by the U.S. Department of the Interior and other agencies. Forecasting future wildlife responses to changes in the Arctic can benefit greatly from historical records that inform what changes have already occurred. Several Arctic wildlife and plant species have already responded to climatic and physical changes to the Arctic Coastal Plain of northern Alaska. Thus, we located historical aerial imagery to improve our understanding of recent habitat changes and the associated response to such changes by wildlife populations.

Towards a more complete SOCCR: Establishing a Coastal Carbon Data Network

Science.gov (United States)

Pidgeon, E.; Howard, J.; Tang, J.; Kroeger, K. D.; Windham-Myers, L.

2015-12-01

The 2007 State of the Carbon Cycle Report (SOCCR) was highly influential in ensuring components of the carbon cycle were accounted for in national policy and related management. However, while SOCCR detailed the significance of North American coastal wetlands, it was not until recently that leading governments began to fully recognized these ecosystems for their carbon sequestration and storage capacity and hence the significant role coastal ecosystems can play in GHG emission reductions strategies, offset mechanisms, coastal management strategies and climate mitigation policy. The new attention on coastal carbon systems has exposed limitations in terms of data availability and data quality, as well as insufficient knowledge of coastal carbon distributions, characteristics and coastal carbon cycle processes. In addition to restricting scientific progress, lack of comprehensive, comparable, and quality-controlled coastal carbon data is hindering progress towards carbon based conservation and coastal management. To directly address those limitations, we are developing a Global Science and Data Network for Coastal "Blue" Carbon, with support from the Carbon Cycle Interagency Working Group. Goals include: • Improving basic and applied science on carbon and GHG cycling in vegetated coastal ecosystems; • Supporting a coastal carbon and associated GHG data archive for use by the science community, coastal and climate practitioners and other data users; • Building the capacity of coastal carbon stakeholders globally to collect and interpret high quality coastal carbon science and data; • Providing a forum and mechanism to promote exchange and collaboration between scientists and coastal carbon data users globally; and • Outreach activities to ensure the best available data are globally accessible and that science is responsive to the needs of coastal managers and policy-makers.

Abyssal Upwelling and Downwelling and the role of boundary layers

Science.gov (United States)

McDougall, T. J.; Ferrari, R. M.

2016-02-01

The bottom-intensified mixing activity arising from the interaction of internal tides with bottom topography implies that the dianeutral advection in the ocean interior is downwards, rather than upwards as is required by continuity. The upwelling of Bottom Water through density surfaces in the deep ocean is however possible because of the sloping nature of the sea floor. A budget study of the abyss (deeper than 2000m) will be described that shows that while the upwelling of Bottom Water might be 25 Sv, this is achieved by very strong upwelling in the bottom turbulent boundary layer (of thickness 50m) of 100 Sv and strong downwelling in the ocean interior of 75 Sv. This downwelling occurs within 10 degrees of longitude of the continental boundaries. This near-boundary confined strong upwelling and downwelling clearly has implications for the Stommel-Arons circulation.

Long-time observation of annual variation of Taiwan Strait upwelling in summer season

Science.gov (United States)

Tang, D. L.; Kawamura, H.; Guan, L.

The Taiwan Strait is between Taiwan Island and Mainland China, where several upwelling zones are well known for good fishing grounds. Earlier studies in the strait have been conducted on detecting upwelling by ship measurements with short-term cruises, but long-term variations of upwelling in this region are not understood. The present paper examines satellite images for a long-time observation of two major upwelling zones in the Taiwan Strait: Taiwan Bank Upwelling (TBU) and Dongshan Upwelling (DSU). Sea surface temperature (SST) and chlorophyll a (Chl-a) images have been analyzed for summer months (June, July, and August) from 1980 to 2002. Results reveal annual variation of two upwelling zones. These two upwelling zones occur every year characterized with distinct low water temperature and high Chl-a concentrations. During the period from 1989 to 1998, SST is found to be 1.15 °C lower in TBU, and 1.42 °C lower in the DSU than the Taiwan Strait. The size of DSU has been found to be larger during summer of 1989, 1990, 1993 and 1995; TBU has been found to be weak during summer of 1994 and 1997. Ocean color images obtained from CZCS, OCI, and SeaWiFS also show high Chl-a concentrations (0.8-2.5 mg m-3) in two upwelling zones, which coincide with low SST in terms of location, shape, and time. These high Chl-a concentrations in TBU and DSU may be related to upwelling waters that bring nutrients from bottom to surface. The present results also show the potential of using satellite data for monitoring of ocean environment for long time period.

Tracking the Fate of Explosive-Trinitrotriazine (RDX) in Coastal Marine Ecosystems Using Stable Isotopic Tracer

Science.gov (United States)

Ariyarathna, T. S.; Ballentine, M.; Vlahos, P.; Smith, R. W.; Bohlke, J. K.; Tobias, C. R.; Fallis, S.; Groshens, T.; Cooper, C.

2017-12-01

It has been estimated that there are hundreds of explosive-contaminated sites all over the world and managing these contaminated sites is an international challenge. As coastal zones and estuaries are commonly impacted zones, it is vital to understand the fate and transport of munition compounds in these environments. The demand for data on sorption, biodegradation and mineralization of trinitrotriazine (RDX) in coastal ecosystems is the impetus for this study using stable nitrogen isotopes to track its metabolic pathways. Mesocosm experiments representing subtidal vegetated, subtidal unvegetated and intertidal marsh ecocosms were conducted. Steady state concentrations of RDX were maintained in the systems throughout two-week time duration of experiments. Sediment, pore-water and overlying water samples were analyzed for RDX and degradation products. Isotope analysis of the bulk sediments revealed an initial rising inventory of 15N followed by a decay illustrating the role of sediments on sorption and degradation of RDX in anaerobic sediments respectively. Both pore-water and overlying water samples were analyzed for 15N inventories of different inorganic nitrogen pools including ammonium, nitrate, nitrite, nitrous oxide and nitrogen gases. RDX is mineralized to nitrogen gas through a series of intermediates leaving nitrous oxide as the prominent metabolite of RDX. Significant differences in RDX metabolism were observed in the three different ecosystems based on sediment characteristics and redox conditions in the systems. Fine grained organic carbon rich sediments show notably higher mineralization rates of RDX in terms of production of its metabolites. Quantification of degradation and transformation rates leads to mass balances of RDX in the systems. Further analysis of results provides insights for mineralization pathways of RDX into both organic and inorganic nitrogen pools entering the marine nitrogen cycle.

Satellite infrared imagery for thermal plume contamination monitoring in coastal ecosystem of Cernavoda NPP

Science.gov (United States)

Zoran, M. A.; Zoran, Liviu Florin V.; Dida, Adrian I.

2017-10-01

Satellite remote sensing is an important tool for spatio-temporal analysis and surveillance of NPP environment, thermal heat waste of waters being a major concern in many coastal ecosystems involving nuclear power plants. As a test case the adopted methodology was applied for 700x2 MW Cernavoda nuclear power plant (NPP) located in the South-Eastern part of Romania, which discharges warm water affecting coastal ecology. The thermal plume signatures in the NPP hydrological system have been investigated based on TIR (Thermal Infrared) spectral bands of NOAA AVHRR, Landsat TM/ETM+/OLI, and MODIS Terra/Aqua time series satellite data during 1990-2016 period. If NOAA AVHRR data proved the general pattern and extension of the thermal plume signature in Danube river and Black Sea coastal areas, Landsat TM/ETM and MODIS data used for WST (Water Surface Temperature) change detection, mapping and monitoring provided enhanced information about the plume shape, dimension and direction of dispersion in these waters. Thermal discharge from two nuclear reactors cooling is dissipated as waste heat in Danube-Black -Sea Channel and Danube River. From time-series analysis of satellite data during period 1990-2016 was found that during the winter season thermal plume was localized to an area of a few km of NPP, and the mean temperature difference between the plume and non-plume areas was about 1.7 oC. During summer and fall, derived mean temperature difference between the plume and non-plume areas was of about 1.3°C and thermal plume area was extended up to 5- 10 km far along Danube Black Sea Channel.

An Altimetry-Derived Index of the Offshore Forcing on the "Pressure Point" of the West Florida Shelf: Anomalous Upwelling and Its Influence on Harmful Algal Blooms

Science.gov (United States)

Liu, Y.; Weisberg, R. H.; Lenes, J. M.; Zheng, L.; Hubbard, K.; Walsh, J. J.

2017-12-01

Gulf of Mexico Loop Current (LC) interactions with the West Florida Shelf (WFS) slope play an important role in shelf ecology through the upwelling of new inorganic nutrients across the shelf break. This is particularly the case when the LC impinges upon the shelf slope in the southwest portion of the WFS near the Dry Tortugas. By contacting shallow water isobaths at this "pressure point" the LC forcing sets the entire shelf into motion. Characteristic patterns of LC interactions with the WFS and their occurrences are identified from altimetry data using unsupervised neural network, self-organizing map. The duration of the occurrences of such LC patterns is used as an indicator of offshore forcing of anomalous upwelling. Consistency is found between the altimetry-derived offshore forcing and the occurrence and severity of WFS coastal blooms of the toxic dinoflagellate, Karenia brevis: years without major blooms tend to have prolonged LC contact at the "pressure point," whereas years with major blooms tend not to have prolonged offshore forcing. Resetting the nutrient state of the shelf by the coastal ocean circulation in response to deep-ocean forcing demonstrates the importance of physical oceanography in shelf ecology. A satellite altimetry-derived seasonal predictor for major K. brevis blooms is also proposed.

Ekman estimates of upwelling at cape columbine based on ...

African Journals Online (AJOL)

Ekman estimates of upwelling at cape columbine based on measurements of longshore wind from a 35-year time-series. AS Johnson, G Nelson. Abstract. Cape Columbine is a prominent headland on the south-west coast of Africa at approximately 32°50´S, where there is a substantial upwelling tongue, enhancing the ...

Modeling Coastal Vulnerability through Space and Time.

Science.gov (United States)

Hopper, Thomas; Meixler, Marcia S

2016-01-01

Coastal ecosystems experience a wide range of stressors including wave forces, storm surge, sea-level rise, and anthropogenic modification and are thus vulnerable to erosion. Urban coastal ecosystems are especially important due to the large populations these limited ecosystems serve. However, few studies have addressed the issue of urban coastal vulnerability at the landscape scale with spatial data that are finely resolved. The purpose of this study was to model and map coastal vulnerability and the role of natural habitats in reducing vulnerability in Jamaica Bay, New York, in terms of nine coastal vulnerability metrics (relief, wave exposure, geomorphology, natural habitats, exposure, exposure with no habitat, habitat role, erodible shoreline, and surge) under past (1609), current (2015), and future (2080) scenarios using InVEST 3.2.0. We analyzed vulnerability results both spatially and across all time periods, by stakeholder (ownership) and by distance to damage from Hurricane Sandy. We found significant differences in vulnerability metrics between past, current and future scenarios for all nine metrics except relief and wave exposure. The marsh islands in the center of the bay are currently vulnerable. In the future, these islands will likely be inundated, placing additional areas of the shoreline increasingly at risk. Significant differences in vulnerability exist between stakeholders; the Breezy Point Cooperative and Gateway National Recreation Area had the largest erodible shoreline segments. Significant correlations exist for all vulnerability (exposure/surge) and storm damage combinations except for exposure and distance to artificial debris. Coastal protective features, ranging from storm surge barriers and levees to natural features (e.g. wetlands), have been promoted to decrease future flood risk to communities in coastal areas around the world. Our methods of combining coastal vulnerability results with additional data and across multiple time

Are large macroalgal blooms necessarily bad? Nutrient impacts on seagrass in upwelling-influenced estuaries.

Science.gov (United States)

Hessing-Lewis, Margot L; Hacker, Sally D; Menge, Bruce A; McConville, Sea-oh; Henderson, Jeremy

2015-07-01

Knowledge of nutrient pathways and their resulting ecological interactions can alleviate numerous environmental problems associated with nutrient increases in both natural and managed systems. Although not unique, coastal systems are particularly prone to complex ecological interactions resulting from nutrient inputs from both the land and sea. Nutrient inputs to coastal systems often spur ulvoid macroalgal blooms, with negative consequences for seagrasses, primarily through shading, as well as through changes in local biogeochemistry. We conducted complementary field and mesocosm experiments in an upwelling-influenced estuary, where marine-derived nutrients dominate, to understand the direct and indirect effects of nutrients on the macroalgal-eelgrass (Zostera marina L.) interaction. In the field experiment, we found weak evidence that nutrients and/or macroalgal treatments had a negative effect on eelgrass. However, in the mesocosm experiment, we found that a combination of nutrient and macroalgal treatments led to strongly negative eelgrass responses, primarily via indirect effects associated with macroalgal additions. Together, increased total light attenuation and decreased sediment oxygen levels were associated with larger effects on eelgrass than shading alone, which was evaluated using mimic algae treatments that did not alter sediment redox potential. Nutrient addition in the mesocosms directly affected seagrass density; biomass, and morphology, but not as strongly as macroalgae. We hypothesize that the contrary results from these parallel experiments are a consequence of differences in the hydrodynamics between field and mesocosm settings. We suggest that the high rates of water movement and tidal submersion of our intertidal field experiments alleviated the light reduction and negative biogeochemical changes in the sediment associated with macroalgal canopies, as well as the nutrient effects observed in the mesocosm experiments. Furthermore, adaptation

Uncovering a New Current: The Southwest MAdagascar Coastal Current

Science.gov (United States)

Ramanantsoa, Juliano D.; Penven, P.; Krug, M.; Gula, J.; Rouault, M.

2018-02-01

Cruise data sets, satellite remote sensing observations, and model data analyses are combined to highlight the existence of a coastal surface poleward flow in the southwest of Madagascar: the Southwest MAdagascar Coastal Current (SMACC). The SMACC is a relatively shallow (water surface signature of the SMACC extends from 22°S (upstream) to 26.4°S (downstream). The SMACC exhibits a seasonal variability: more intense in summer and reduced in winter. The average volume transport of its core is about 1.3 Sv with a mean summer maximum of 2.1 Sv. It is forced by a strong cyclonic wind stress curl associated with the bending of the trade winds along the southern tip of Madagascar. The SMACC directly influences the coastal upwelling regions south of Madagascar. Its existence is likely to influence local fisheries and larval transport patterns, as well as the connectivity with the Agulhas Current, affecting the returning branch of the global overturning circulation.

A long history of equatorial deep-water upwelling in the Pacific Ocean

Science.gov (United States)

Zhang, Yi Ge; Pagani, Mark; Henderiks, Jorijntje; Ren, Haojia

2017-06-01

Cold, nutrient- and CO2-rich waters upwelling in the eastern equatorial Pacific (EEP) give rise to the Pacific cold tongue. Quasi-periodic subsidence of the thermocline and attenuation in wind strength expressed by El Niño conditions decrease upwelling rates, increase surface-water temperatures in the EEP, and lead to changes in regional climates both near and far from the equatorial Pacific. EEP surface waters have elevated CO2 concentrations during neutral (upwelling) or La Niña (strong upwelling) conditions. In contrast, approximate air-sea CO2 equilibrium characterizes El Niño events. One hypothesis proposes that changes in physical oceanography led to the establishment of a deep tropical thermocline and expanded mixed-layer prior to 3 million years ago. These effects are argued to have substantially reduced deep-water upwelling rates in the EEP and promoted a "permanent El Niño-like" climate state. For this study, we test this supposition by reconstructing EEP "excess CO2" and upwelling history for the past 6.5 million years using the alkenone-pCO2 methodology. Contrary to previous assertions, our results indicate that average temporal conditions in the EEP over the past ∼6.5 million years were characterized by substantial CO2 disequilibrium and high nutrient delivery to surface waters - characteristics that imply strong upwelling of deep waters. Upwelling appears most vigorous between ∼6.5 to 4.5 million years ago coinciding with high accumulation rates of biogenic material during the late Miocene - early Pliocene "biogenic bloom".

Evaluating the Ability of Oysters (Crassostrea virginica) to Mitigate Coastal Nitrogen Over-Enrichment

Science.gov (United States)

Human actions have resulted in a doubling of the rate of bio-available nitrogen production in the biosphere, leading to over-fertilization of coastal ecosystems worldwide. Such over-fertilization has numerous negative consequences for coastal ecosystems, such as excessive algal g...

Exploring the ecosystem engineering ability of Red Sea shallow benthic habitats using stocks and fluxes in carbon biogeochemistry