WorldWideScience

Sample records for river lagoon florida

  1. Benthic Habitat Mapping - Indian River Lagoon, Florida Submerged Aquatic Vegetation (SAV) Data 1996 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Office for Coastal Management's Coastal Change Analysis Program, in cooperation with the St. Johns River and South Florida Water Management Districts, used...

  2. Benthic Habitat Mapping - Indian River Lagoon, Florida Submerged Aquatic Vegetation (SAV) Data 1996 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Office for Coastal Management's Coastal Change Analysis Program, in cooperation with the St. Johns River and South Florida Water Management Districts, used...

  3. Benthic Habitat Mapping - Indian River Lagoon, Florida Submerged Aquatic Vegetation (SAV) Data 1996 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Office for Coastal Management's Coastal Change Analysis Program, in cooperation with the St. Johns River and South Florida Water Management Districts, used...

  4. Multivariate Statistical Analysis of Water Quality data in Indian River Lagoon, Florida

    Science.gov (United States)

    Sayemuzzaman, M.; Ye, M.

    2015-12-01

    The Indian River Lagoon, is part of the longest barrier island complex in the United States, is a region of particular concern to the environmental scientist because of the rapid rate of human development throughout the region and the geographical position in between the colder temperate zone and warmer sub-tropical zone. Thus, the surface water quality analysis in this region always brings the newer information. In this present study, multivariate statistical procedures were applied to analyze the spatial and temporal water quality in the Indian River Lagoon over the period 1998-2013. Twelve parameters have been analyzed on twelve key water monitoring stations in and beside the lagoon on monthly datasets (total of 27,648 observations). The dataset was treated using cluster analysis (CA), principle component analysis (PCA) and non-parametric trend analysis. The CA was used to cluster twelve monitoring stations into four groups, with stations on the similar surrounding characteristics being in the same group. The PCA was then applied to the similar groups to find the important water quality parameters. The principal components (PCs), PC1 to PC5 was considered based on the explained cumulative variances 75% to 85% in each cluster groups. Nutrient species (phosphorus and nitrogen), salinity, specific conductivity and erosion factors (TSS, Turbidity) were major variables involved in the construction of the PCs. Statistical significant positive or negative trends and the abrupt trend shift were detected applying Mann-Kendall trend test and Sequential Mann-Kendall (SQMK), for each individual stations for the important water quality parameters. Land use land cover change pattern, local anthropogenic activities and extreme climate such as drought might be associated with these trends. This study presents the multivariate statistical assessment in order to get better information about the quality of surface water. Thus, effective pollution control/management of the surface

  5. Nitrogen limitation of growth and nutrient dynamics in a disturbed mangrove forest, Indian River Lagoon, Florida

    Science.gov (United States)

    Feller, Ilka C.; Whigham, D.F.; McKee, K.L.; Lovelock, C.E.

    2003-01-01

    The objectives of this study were to determine effects of nutrient enrichment on plant growth, nutrient dynamics, and photosynthesis in a disturbed mangrove forest in an abandoned mosquito impoundment in Florida. Impounding altered the hydrology and soil chemistry of the site. In 1997, we established a factorial experiment along a tree-height gradient with three zones, i.e., fringe, transition, dwarf, and three fertilizer treatment levels, i.e., nitrogen (N), phosphorus (P), control, in Mosquito Impoundment 23 on the eastern side of Indian River. Transects traversed the forest perpendicular to the shoreline, from a Rhizophora mangle-dominated fringe through an Avicennia germinans stand of intermediate height, and into a scrub or dwarf stand of A. germinans in the hinterland. Growth rates increased significantly in response to N fertilization. Our growth data indicated that this site is N-limited along the tree-height gradient. After 2 years of N addition, dwarf trees resembled vigorously growing saplings. Addition of N also affected internal dynamics of N and P and caused increases in rates of photosynthesis. These findings contrast with results for a R. mangle-dominated forest in Belize where the fringe is N-limited, but the dwarf zone is P-limited and the transition zone is co-limited by N and P. This study demonstrated that patterns of nutrient limitation in mangrove ecosystems are complex, that not all processes respond similarly to the same nutrient, and that similar habitats are not limited by the same nutrient when different mangrove forests are compared.

  6. Seasonality of selected surface water constituents in the Indian River Lagoon, Florida.

    Science.gov (United States)

    Qian, Y; Migliaccio, K W; Wan, Y; Li, Y C; Chin, D

    2007-01-01

    Seasonality is often the major exogenous effect that must be compensated for or removed to discern trends in water quality. Our objective was to provide a methodological example of trend analysis using water quality data with seasonality. Selected water quality constituents from 1979 to 2004 at three monitoring stations in southern Florida were evaluated for seasonality. The seasonal patterns of flow-weighted and log-transformed concentrations were identified by applying side-by-side boxplots and the Wilcoxon signed-rank test (p turbidity, color, and chloride), except for turbidity at Station C24S49, exhibited significant seasonal patterns. Almost all nutrient species (NO(2)-N, NH(4)-N, total Kjeldahl N, PO(4)-P, and total P) had an identical seasonal pattern of concentrations significantly greater in the wet than in the dry season. Some water quality constituents were observed to exhibit significant annual or seasonal trends. In some cases, the overall annual trend was insignificant while opposing trends were present in different seasons. By evaluating seasonal trends separately from all data, constituents can be assessed providing a more accurate interpretation of water quality trends.

  7. Water-Quality Monitoring and Biological Integrity Assessment in the Indian River Lagoon, Florida: Status, Trends, and Loadings (1988-1994).

    Science.gov (United States)

    Sigua; Steward; Tweedale

    2000-02-01

    / The Indian River Lagoon (IRL) system that extends from Ponce DeLeon Inlet to Jupiter Inlet is comprised of three interconnected estuarine lagoons: the Mosquito Lagoon (ML), the Banana River Lagoon (BRL), and the Indian River Lagoon (subdivided into North Indian River Lagoon, NIRL and the South Indian River Lagoon, SIRL). The declines in both the areal coverage and species diversity of seagrass communities within the IRL system are believed to be due in part to continued degradation of water quality. Large inflows of phosphorus (P) and nitrogen (N) -laden storm-water from urban areas and agricultural land have been correlated with higher chlorophyll a production in the central, south central, and the south segments of the lagoon. In a system as large and complex as the lagoon, N and P limitations are potentially subject to significant spatial and temporal variability. Total Kjeldahl nitrogen (TN) was higher in the north (1.25 mg/liter) and lower in the south (0.89 mg/liter). The reverse pattern was observed for total P (TP), i.e., lowest in the north (0.03 mg/liter) and highest at the south (0.14 mg/liter) ends of the IRL. This increased P concentration in the SIRL appears to have a significantly large effect on chlorophyll a production compared with the other segments, as indicated by stepwise regression statistics. This relationship can be expressed as follows: South IRL [chlorophyll a] = -8.52 + 162.41 [orthophosphate] + 7.86 [total nitrogen] + 0.38 [turbidity]; R(2) = 0.98**.

  8. Water-quality monitoring and biological integrity assessment in the Indian River Lagoon, Florida: Status, trends, and loadings (1988--1994)

    Energy Technology Data Exchange (ETDEWEB)

    Sigua, G.C.; Steward, J.S.; Tweedale, W.A.

    2000-02-01

    The Indian River Lagoon (IRL) system that extends from Ponce DeLeon inlet to Jupiter inlet is comprised of three interconnected estuarine lagoons: The Mosquito Lagoon (ML), the Banana River Lagoon (BRL), and the Indian River Lagoon. The declines in both the aerial coverage and species diversity of seagrass communities within the IRL system are believed to be due in part to continued degradation of water quality. Large inflows of phosphorus (P) and nitrogen (N)-laden storm-water from urban areas an agricultural land have been correlated with higher chlorophyll a production in the central, south central, and the south segments of the lagoon. In a system as large and complex as the lagoon, N and P limitations are potentially subject to significant spatial and temporal variability. Total Kjeidahl nitrogen (TN) was higher in the north and lower in the south. The reverse pattern was observed for total P (TP), i.e., lowest in the north and highest at the south ends of the IRL. This increased P concentration in the SIRL appears to have a significantly large effect on chlorophyll a production compared with the other segments, as indicated by stepwise regression statistics. This relationship can be expressed as follows: South IRL [chlorophyll a] = {minus}8.52 + 162.41 [orthophosphate] + 7.86 [total nitrogen] + 0.38 [turbidity]; R{sup 2} = 0.98**.

  9. Flow-sediment-oyster interaction around degraded, restored, and reference oyster reefs in Florida's Indian River Lagoon

    Science.gov (United States)

    Kitsikoudis, V.; Kibler, K. M.; Spiering, D. W.

    2017-12-01

    This study analyzes flow patterns and sediment distributions around three oyster reefs in a bar-built estuarine lagoon. We studied a degraded reef, a recently restored reef, and a reference condition reef with a healthy live oyster community. The restored reef had been regraded and restored with oyster shell mats to aid in recruitment of oyster spat, with the goal of reestablishing a healthy oyster community. Despite the fact that flow-biota-sediment interaction constitutes a blossoming research field, actual field data are sparse and current knowledge emanates from flume studies and numerical modeling. Moreover, the hydraulic effect of restored oyster reefs has not been thoroughly investigated and it is not clear if the flow field and sediment erosion/deposition are similar or diverge from natural reefs. Instantaneous three-dimensional flow velocities were collected on reefs using a Nortek Vectrino Profiler and an acoustic Doppler current profiler (Nortek Aquadopp). The former measured a 2 - 3 cm velocity profile above the oyster bed, while the latter quantified incoming velocities across the flow profile approximately 10 m from the edge of the reef. Flow measurements were conducted during rising tides and are coupled with simultaneous wind speed and direction data. In addition, 20 cm deep sediment cores were retrieved on and off the investigated reefs. Sediment grain size distributions were determined after individual cores were processed for loss on ignition. Incoming flow velocities were as high as 10 cm/s, relatively higher than those recorded close to reefs. Mean and turbulent flow velocities close to the reefs, varied among the investigated sites, despite the similar wind flow conditions offshore. For instance, the measurements at the degraded reef showed decreased wave attenuation and augmented flow velocities compared to the other sites. Boat wakes exhibited a very distinct signal in the flow velocity time-series and significantly increased the approaching

  10. Surface Water Quality Survey of Northern Indian River Lagoon from Sebastian Inlet to Mosquito Lagoon

    Science.gov (United States)

    Weaver, R. J.; Webb, B. M.

    2012-12-01

    Following news of an emerging brown tide algal bloom in the northern Indian River Lagoon (IRL), researchers sought to gain insight into the surface water quality in the IRL, as well as the extent of the algae coverage. A Portable SeaKeeper from YSI, mounted to a personal watercraft-based coastal profiling system, autonomously collected and analyzed the surface water. The system operates by recording sample data every 12 seconds while continuously underway at speeds up to and greater than 50 km/hr. The researchers covered a transect that started at Sebastian Inlet and followed a zig-zag path extending up through the Haulover Canal and into the Mosquito Lagoon. The survey path covered 166.7 km, and collected 2248 samples. Along the way stops were made at water quality stations used by the Saint John's River Water Management District, so that the data collected can be incorporated into ongoing monitoring efforts. The system analyzed the surface water for dissolved oxygen, pH, chlorophyll-a, salinity, temperature, turbidity, refined fuels, and CDOM. In the two days following the lagoon survey, the inlets at Port Canaveral and Sebastian were also surveyed for tidal currents and hydrography. The IRL transect survey data recorded evidence of the southern extent of the algae bloom in both chlorophyll-a and pH levels. Visual evidence of the bloom was striking as the water in the northern IRL turned a milk chocolaty brown color. Chlorophyll-a levels in the two inlets suggested bloom activity at these locations; however this bloom was different. This oceanic bloom was a result of a persistent upwelling event along the East Florida shelf, and the color was a paler green-yellow. The near-synoptic nature of the comprehensive lagoon survey, conducted in just over 7 hours, allows researchers to obtain a better understanding of water quality in coastal lagoons. Elevated levels of salinity, temperature, and refined fuels in the northern IRL indicate a low exchange rate and absence

  11. Advection within shallow pore waters of a coastal lagoon, Florida

    Science.gov (United States)

    Cable, J.E.; Martin, Jonathan B.; Swarzenski, Peter W.; Lindenberg, Mary K.; Steward, Joel

    2004-01-01

    Ground water sources can be a significant portion of a local water budget in estuarine environments, particularly in areas with high recharge rates, transmissive aquifers, and permeable marine sediments. However, field measurements of ground water discharge are often incongruent with ground water flow modeling results, leaving many scientists unsure which estimates are accurate. In this study, we find that both measurements and model results are reasonable. The difference between estimates apparently results from the sources of water being measured and not the techniques themselves. In two locations in the Indian River Lagoon estuarine system, we found seepage meter rates similar to rates calculated from the geochemical tracers 222Rn and 226Ra. Ground water discharge rates ranged from 4 to 9 cm/d using seepage meters and 3 to 20 cm/d using 222Rn and 226Ra. In contrast, in comparisons to other studies where finite element ground water flow modeling was used, much lower ground water discharge rates of ∼0.05 to 0.15 cm/d were estimated. These low rates probably represent discharge of meteoric ground water from land-recharged aquifers, while the much higher rates measured with seepage meters, 222Rn, and 226Ra likely include an additional source of surface waters that regularly flush shallow (recharged water and recirculated surface waters contributes to the total biogeochemical loading in this shallow estuarine environment.

  12. Intertidal deposits: river mouths, tidal flats, and coastal lagoons

    NARCIS (Netherlands)

    Eisma, D.; Boer, de P.L.; Cadee, G.C.; Dijkema, K.; Ridderinkhof, H.; Phillippart, C.

    1998-01-01

    Intertidal Deposits: River Mouths, Tidal Flats, and Coastal Lagoons combines the authors personal and professional experience with the mass of available literature to present a cohesive overview of intertidal deposits and the widely diverse conditions of their formation worldwide. This includes the

  13. A Tale of Two Inlets: Tidal Currents at Two Adjacent Inlets in the Indian River Lagoon

    Science.gov (United States)

    Webb, B. M.; Weaver, R. J.

    2012-12-01

    The tidal currents and hydrography at two adjacent inlets of the Indian River Lagoon estuary (Florida) were recently measured using a personal watercraft-based coastal profiling system. Although the two inlets—Sebastian Inlet and Port Canaveral Inlet—are separated by only 60 km, their characteristics and dynamics are quite unique. While Sebastian Inlet is a shallow (~4 m), curved inlet with a free connection to the estuary, Port Canaveral Inlet is dominated by a deep (~13 m), straight ship channel and has limited connectivity to the Banana River through a sector gate lock. Underway measurements of tidal currents were obtained using a bottom tracking acoustic Doppler current profiler; vertical casts of hydrography were obtained with a conductivity-temperature-depth profiling instrument; and continuous underway measurements of surface water hydrography were made using a Portable SeaKeeper system. Survey transects were performed to elucidate the along-channel variability of tidal flows, which appears to be significant in the presence of channel curvature. Ebb and flood tidal currents in Sebastian Inlet routinely exceeded 2.5 m/s from the surface to the bed, and an appreciable phase lag exists between tidal stage and current magnitude. The tidal currents at Port Canaveral Inlet were much smaller (~0.2 m/s) and appeared to be sensitive to meteorological forcing during the study period. Although the lagoon has free connections to the ocean 145 km to the north and 45 km to the south, Sebastian Inlet likely drains much of the lagoon to its north, an area of ~550 sq. km.

  14. Non-native fishes of the central Indian River Lagoon

    Science.gov (United States)

    Schofield, Pamela J.; Loftus, William F.; Reaver, Kristen M.

    2018-01-01

    We provide a comprehensive review of the status of non-native fishes in the central Indian River Lagoon (from Cape Canaveral to Grant-Valkaria, east of I-95) through literature review and field surveys. Historical records exist for 17 taxa (15 species, one hybrid, one species complex). We found historical records for one additional species, and collected one species in our field survey that had never been recorded in the region before (and which we eradicated). Thus, we evaluate 19 total taxa herein. Of these, we documented range expansion of four salt-tolerant cichlid species, extirpation of six species that were previously recorded from the area and eradication of three species. There was no noticeable change in geographic range for one widespread species and the records for one species are doubtful and may be erroneous. Currently, there is not enough information to evaluate geographic ranges for four species although at least one of those is established.

  15. Hyperspectral signatures and WorldView-3 imagery of Indian River Lagoon and Banana River Estuarine water and bottom types

    Science.gov (United States)

    Bostater, Charles R.; Oney, Taylor S.; Rotkiske, Tyler; Aziz, Samin; Morrisette, Charles; Callahan, Kelby; Mcallister, Devin

    2017-10-01

    Hyperspectral signatures and imagery collected during the spring and summer of 2017 and 2016 are presented. Ground sampling distances (GSD) and pixel sizes were sampled from just over a meter to less than 4.0 mm. A pushbroom hyperspectral imager was used to calculate bidirectional reflectance factor (BRF) signatures. Hyperspectral signatures of different water types and bottom habitats such as submerged seagrasses, drift algae and algal bloom waters were scanned using a high spectral and digital resolution solid state spectrograph. WorldView-3 satellite imagery with minimal water wave sun glint effects was used to demonstrate the ability to detect bottom features using a derivative reflectance spectroscopy approach with the 1.3 m GSD multispectral satellite channels centered at the solar induced fluorescence band. The hyperspectral remote sensing data collected from the Banana River and Indian River Lagoon watersheds represents previously unknown signatures to be used in satellite and airborne remote sensing of water in turbid waters along the US Atlantic Ocean coastal region and the Florida littoral zone.

  16. Oualidia lagoon, Morocco: an estuary without a river | Hilmi | African ...

    African Journals Online (AJOL)

    Coupled 2D hydrodynamic and advection-dispersion models (MIKE21) were then used to verify some renewal times. The tidally averaged renewal time for the whole lagoon was found to be 7 days, while the local renewal time at the upstream end of the lagoon was 25 days. Finally, an inverse modelling approach using ...

  17. Biodegradation of hexadecane using sediments from rivers and lagoons of the Southern Gulf of Mexico.

    Science.gov (United States)

    García-Cruz, N Ulises; Sánchez-Avila, Juan I; Valdés-Lozano, David; Gold-Bouchot, Gerardo; Aguirre-Macedo, Leopoldina

    2018-03-01

    The Southern Gulf of Mexico is an area highly impacted by crude oil extraction, refining activities and the presence of natural petroleum seepage. Oceanic currents in the Gulf of Mexico continually facilitate the transport of hydrocarbons to lagoons and rivers. This research evaluated hexadecane (HXD) degradation in marine sediment samples from lagoons and rivers that are fed by the Southern Gulf of Mexico, specifically six samples from rivers, three samples from lagoons, and one sample from a marine outfall. The highest rates of biodegradation were observed in sediments from the mouths of the Gonzalez River and the Champotón Lagoon. The lowest consumption rate was found in sediment from the mouth of the Coatzacoalcos River. With regards to the Ostión Lagoon and the Grijalva River, there was a low rate of consumption, but a high efficiency of degradation which took place at the end of the experiments. No correlation was found between the consumption rate and the environmental physicochemical parameters. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. 2008 Florida Division of Emergency Management Lidar: Middle Suwannee River

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — LiDAR Survey for the Suwannee River Water Management District (SRWMD), Florida. The LiDAR aerial acquisition was conducted in January of 2008, and the breaklines and...

  19. Carmel River Lagoon Enhancement Project: Water Quality and Aquatic Wildlife Monitoring, 2006-7

    OpenAIRE

    Perry, William; Watson, Fred; Casagrande, Joel; Hanley, Charles

    2007-01-01

    This is a report to the California Department of Parks and Recreation. It describes water quality and aquatic invertebrate monitoring after the construction of the Carmel River Lagoon Enhancement Project. Included are data that have been collected for two years and preliminary assessment of the enhanced ecosystem. This report marks the completion of 3-years of monitoring water quality and aquatic habitat. The report adopts the same format and certain background text from previous ...

  20. Aquatic vegetation were photographed from aircraft from Florida Bay, Indian River (Florida), and the Coast of Massachusetts (NODC Accession 0000411)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Aerial photographs were taken of the aquatic vegetation of Florida Bay, Indian River (Florida), and the Coast of Massachusetts. Photographs were scanned and...

  1. Harmful algae records in Venice lagoon and in Po River Delta (northern Adriatic Sea, Italy).

    Science.gov (United States)

    Facca, Chiara; Bilaničovà, Dagmar; Pojana, Giulio; Sfriso, Adriano; Marcomini, Antonio

    2014-01-01

    A detailed review of harmful algal blooms (HAB) in northern Adriatic Sea lagoons (Po River Delta and Venice lagoon) is presented to provide "updated reference conditions" for future research and monitoring activities. In the study areas, the high mollusc production requires the necessity to identify better methods able to prevent risks for human health and socioeconomical interests. So, an integrated approach for the identification and quantification of algal toxins is presented by combining microscopy techniques with Liquid Chromatography coupled with High Resolution Time of Flight Mass Spectrometry (HPLC-HR-TOF-MS). The method efficiency was first tested on some samples from the mentioned coastal areas, where Dinophysis spp. occurred during summer in the sites directly affected by seawaters. Although cell abundance was always <200 cells/L, the presence of Pectenotoxin-2 (PTX2), detected by HPLC-HR-TOF-MS, indicated the potential release of detectable amounts of toxins even at low cell abundance.

  2. Rare earth elements in sediment profiles from marginal lagoons of the Moji-Guacu River basin, Brazil

    International Nuclear Information System (INIS)

    Ferreira, J.R.; Fernandes, E.A.N.; Franca, E.J.; Tavares, G.A.; Silva, N.C. da; Taddei, M.H.T.

    2006-01-01

    Sediment cores from Catingueiro, Barrinha and Rio das Pedras marginal lagoons of the Moji-Guacu River basin were analyzed for rare earth elements (REEs), Fe, Ta and Th by instrumental neutron activation analysis (k 0 -INAA). Data indicated similarities between Catingueiro and Barrinha lagoons, while a distinct scenario was seen for Rio das Pedras likely due to changes of sedimentation rate in 1950's. By using Fe, Sc, Ta and Th as conservative elements, double normalization technique was performed in order to assess the distribution pattern of Ce, Eu, La, Sm and Tb for each core. In all cases, it was evident a depletion of lighter REE elements in the Rio das Pedras lagoon. (author)

  3. Fishes of the Taquari-Antas river basin (Patos Lagoon basin, southern Brazil

    Directory of Open Access Journals (Sweden)

    FG. Becker

    Full Text Available The aquatic habitats of the Taquari-Antas river basin (in the Patos Lagoon basin, southern Brazil are under marked environmental transformation because of river damming for hydropower production. In order to provide an information baseline on the fish fauna of the Taquari-Antas basin, we provide a comprehensive survey of fish species based on primary and secondary data. We found 5,299 valid records of fish species in the basin, representing 119 species and 519 sampling sites. There are 13 non-native species, six of which are native to other Neotropical river basins. About 24% of the total native species are still lacking a taxonomic description at the species level. Three native long-distance migratory species were recorded (Leporinus obtusidens, Prochilodus lineatus, Salminus brasiliensis, as well as two potential mid-distance migrators (Parapimelodus nigribarbis and Pimelodus pintado. Although there is only one officially endangered species in the basin (S. brasiliensis, restricted range species (21.7% of total species should be considered in conservation efforts.

  4. Agrochemical loading in drains and rivers and its connection with pollution in coastal lagoons of the Mexican Pacific.

    Science.gov (United States)

    Arellano-Aguilar, Omar; Betancourt-Lozano, Miguel; Aguilar-Zárate, Gabriela; Ponce de Leon-Hill, Claudia

    2017-06-01

    The state of Sinaloa in Mexico is an industrialized agricultural region with a documented pesticide usage of 700 t year -1 ; which at least 17 of the pesticides are classified as moderately to highly toxic. Pollutants in the water column of rivers and drains are of great concern because the water flows into coastal lagoons and nearshore waters and thereby affects aquatic organisms. This study was done in four municipalities in the state of Sinaloa that produce food intensively. To investigate the link between pollution in the lagoons and their proximity to agricultural sites, water was sampled in three coastal lagoons and in the rivers and drains that flow into them. Seawater from the Gulf of California, 10 km from the coast, was also analyzed. Concentrations of nutrients, organochlorines, and organophosphorus pesticides were determined. Nutrient determination showed an unhealthy environment with N/P ratios of pollution of the coastal lagoon of Pabellones could be traced mainly to the drains from the agricultural sites. Accumulation of OC pesticides was also observed in the Gulf of California. Tests for 22 organophosphates revealed only five (diazinon, disulfoton, methyl parathion, chlorpyrifos, and mevinphos); diazinon was detected at all the sites, although methyl parathion was present at some sites at concentrations one order of magnitude higher than diazinon.

  5. DETECTING FOREST STRESS AND DECLINE IN RESPONSE TO INCREASING RIVER FLOW IN SOUTHWEST FLORIDA, USA

    Science.gov (United States)

    Forest stress and decline resulting from increased river flows were investigated in Myakka River State Park (MRSP), Florida, USA. Since 1977, land-use changes around the upper Myakka River watershed have resulted in significant increases in water entering the river, which have...

  6. Fatal Asphyxiation in Bottlenose Dolphins (Tursiops truncatus from the Indian River Lagoon.

    Directory of Open Access Journals (Sweden)

    Megan Stolen

    Full Text Available Multiple single case reports of asphyxiation in dolphins caused by fish lodged in the esophagus exist. However, the significance of this cause of mortality in a single population has not been documented. We performed a retrospective evaluation of pathology records from stranded bottlenose dolphins (Tursiops truncatus from the Indian River Lagoon to evaluate the impact of this cause of death on this population. From 1997 to 2011, asphyxiation due to choking was identified as the cause of death in 14 of 350 cases (4%. Sampling of an unrelated but adjacent population over this same period yielded 186 necropsy cases of bottlenose dolphins with no cases of asphyxiation. Asphyxiated animals presented with a fish lodged in the cranial esophagus associated with a dislocated and obstructed or compressed larynx. There was no clear sex predilection. Affected animals included 12 adults and two juveniles. The fish species involved included sheepshead, black chin tilapia and striped mojarra. In five cases, recreational fishing gear was also present. Cetacean choking is related to selection of prey fish species with strong dorsal spines and may be secondarily associated with fish attached to fishing gear. Prey abundance and dolphin behavior may influence these selections. Environmental alterations leading to changes in prey availability or increased interactions with fishing gear may change the significance of fatal choking in dolphin populations.

  7. Effects of extended absence of flooding on the fish assemblages of three floodplain lagoons in the middle São Francisco River, Brazil

    Directory of Open Access Journals (Sweden)

    Paulo dos Santos Pompeu

    Full Text Available In the Neotropics, a large proportion of fish communities of large rivers use floodplain as habitats for feeding, reproduction, and refuge. An evaluation was made of the effects of extended dry periods on the species richness, abundance and local extinction of fish species in three marginal lagoons in the middle São Francisco River, southeastern Brazil. The studied lagoons fail to receive river floods during the study period (1994-1996. A gradual reduction in richness and abundance was observed in all lagoons. Migratory fish species had the highest probability to become extinct in the two lagoons that remained with large water volume. Species tolerant to low levels of dissolved oxygen had the lowest probability of local extinction in the lagoon showing an abrupt reduction in water volume. Similar changes to those observed in the current study are likely to occur in the floodplains if dams would be constructed in this segment of the river. Adequate water releases from Três Marias reservoir, located upstream, should be considered as a management tool for producing episodic flooding on the marginal lagoons of the region.

  8. PARASITIC AND SYMBIONIC FAUNA IN OYSTERS (CRASSOSTREA VIRGINICA) COLLECTED FROM THE CALOOSAHATCHEE RIVER AND ESTUARY, FLORIDA

    Science.gov (United States)

    Studies of oysters, Crassostrea virginica, collected from ten sites in the Caloosahatchee River and Estuary, Florida, revealed a varied parasite and symbiotic fauna that have never been reported from this area. Organisms observed included ovacystis virus infecting gametes...

  9. Peculiarities of hydrobiont mutagenesis in complicated ecological areas of the Nemunas river and the Kurshiu marios lagoon

    International Nuclear Information System (INIS)

    Barshiene, J.

    1992-01-01

    Cytogenetic disturbances of Viviparus contectus, Dreisena polymorpha, various bivalves, fish and trematodes species collected from the Nemunas river above Smalininkai, Tilzhe, Rusne, Kurshiu marios lagoon at Nida, Preila, Juodkrante, estuaries of Smiltele (Klaipeda), Vente have been studied. The data show that the highest level of chromosome sets changes was presented at Smalininkai, Vente, Preila and in biotopes of Klaipeda environs. It was marked that 50 % of clams from Smalininkai site were polyploidy and possessed cancer cells in their tissues. The great instability of chromosome sets in snails and unchangeable karyotypes of their parasites were detected. In fish tissues there were 12-21 % of altered cells with aneuploid or polyploid sets. The existence of polyploid, mosaic and hermaphroditic specimens of clams as well as the presence of high amount of cancer cells and mitotic suppression in their tissues, enable to state about complicated ecological zones in the Nemunas river: below Kaunas, Smalininkai, Tilzhe, in the Kurshiu marios lagoon: Vente, environs of Klaipeda and estuaries of the Shventoji river additionally. The highest level of β activity was detected in soft tissues of bivalve specimens containing 24-58 % of hypoploid cells. (author). 5 tabs., 1 fig., 4 refs

  10. Source Water Identification and Chemical Typing for Nitrogen at the Kissimmee River, Pool C, Florida--Preliminary Assessment

    National Research Council Canada - National Science Library

    Phelps, G. G

    2002-01-01

    As part of the South Florida Water Management District's Ground Water-Surface Water Interactions Study, a project was undertaken to identify the ages and sources of water in the area of Pool C, Kissimmee River, Florida...

  11. [The endoparasitic helminths of Pimelodus maculatus Lacépède, 1803 Siluriformes, Pimelodidae) from the two localities (Lagoon and gutter of the River) of the Guandu River, State of Rio de Janeiro, Brazil].

    Science.gov (United States)

    Albuquerque, Marcia C; Santos, Michelle D; Monteiro, Cassandra M; Martins, Amanda N; Ederli, Nicole B; Brasil-Sato, Marilia C

    2008-09-01

    Between November 2003 and March 2004, fourty specimens of Pimelodus maculatus Lacépède, 1803 from Guandu River and thirty-nine from Guandu Lagoon (Nova Iguaçu, RJ) were collected, for the analysis of endoparasitic fauna. A total of 236 specimens of Cucullanus pinnai Travassos, Artigas & Pereira, 1928 (Nematoda, Cucullanidae) were collected, being 163 adult specimens in the gut, three in the stomach and 70 larvae in the celomatic cavity and seven specimens of adults Nomimoscolex sp. (Eucestoda, Proteocephalidea) in the gut were found. Cucullanus pinnai presented prevalence (P) 77.50%, mean intensity (MI) 3.40 and mean abundance (MA) 2.60 on River and P: 66.67%, MI: 5.04, MA: 3.36 on Lagoon. Nomimoscolex sp. presented on River P: 2.50%, MI: 2.00, MA: 0.05, and P: 10.26%, MI: 1.25, MA: 0.13 on Lagoon. There was not significant positive interspecific association on the lagoon. In this research, the endoparasitic richness of P. maculatus was scarcest than similar studies in Guandu River and others rivers of different basins. The results about C. pinnai could be suggesting that the cycle of C. pinnai evolve only a host, occurring a histotrophic fase, in this case, in P. maculatus. Periodic analysis of the endoparasites indices in P. maculatus through the years may be used to describe the hydric quality of the Guandu River.

  12. Hydrology and ecology of the Apalachicola River, Florida : a summary of the river quality assessment

    Science.gov (United States)

    Elder, John F.; Flagg, Sherron D.; Mattraw, Harold C.

    1988-01-01

    During 1979-81, the U.S. Geological Survey conducted a large-scale study of the Apalachicola River in northwest Florida, the largest and one of the most economically important rivers in the State. Termed the Apalachicola River Quality Assessment, the study emphasized interrelations among hydrodynamics, the flood-plain forest, and the nutrient-detritus flow through the river system to the estuary. This report summarizes major findings of the study. Data on accumulation of toxic substances in sediments and benthic organisms in the river were also collected. Because of the multiple uses of the Apalachicola River system, there are many difficult management decisions. The river is a waterway for shipping; hence there is an economic incentive for modification to facilitate movement of barge traffic. Such modifications include the proposed construction of dams, levees, bend easings, and training dikes; ditching and draining in the flood plain; and dredging and snagging in the river channel. The river is also recognized as an important supplier of detritus, nutrients, and freshwater to the Apalachicola Bay, which maintains an economically important shellfish industry. The importance of this input to the bay creates an incentive to keep the river basin in a natural state. Other values, such as timber harvesting, recreation, sport hunting, nature appreciation, and wildlife habitat, add even more to the difficulty of selecting management strategies. Water and nutrient budgets based on data collected during the river assessment study indicate the relative importance of various inputs and outflows in the system. Waterflow is controlled primarily by rainfall in upstream watersheds and is not greatly affected by local precipitation, ground-water exchanges, or evapotranspiration in the basin. On an annual basis, the total nutrient inflow to the system is nearly equal in quantity to total outflow, but there is a difference between inflow and outflow in the chemical and physical

  13. Identifying resuspended sediment in an estuary using the 228Th/232Th activity ratio: the fate of lagoon sediment in the Bega River estuary, Australia

    International Nuclear Information System (INIS)

    Hancock, G.J.

    2000-01-01

    Thorium-series nuclides ( 228 Th and 232 Th) have been used to identify resuspended sediment in the Bega River estuary, south-eastern Australia. A non-conservative increase in concentration of suspended sediment of water in the vicinity of mid-estuary back-flow lagoons was associated with a decrease in the 228 Th/ 232 Th activity ratio (AR) of the suspended sediment. The lagoon sediment is characterized by a low estuarine 228 Th/ 232 Th signature, distinguishing it from freshwater suspended sediment recently delivered to the estuary, and identifying it as the likely source of the additional suspended sediment. Sediment-core 210 TPb profiles show that the lagoons are accumulating sediment, presumably during high river-flow events. However this study indicates that during intervening periods of low flow, 40% of sediment deposited in the lagoons is subsequently resuspended and exported to the lower estuary, and possibly to the ocean. The utility of the 228 Th/ 232 Th AR to quantify sediment resuspension in estuaries is likely to be estuary-dependent, and is controlled by the extent of scavenging of dissolved 228 Th by suspended particles. Copyright (2000) CSIRO Publishing

  14. Hydrologic data summary for the St. Lucie River Estuary, Martin and St. Lucie Counties, Florida, 1998-2001

    Science.gov (United States)

    Byrne, Michael J.; Patino, Eduardo

    2004-01-01

    A hydrologic analysis was made at three canal sites and four tidal sites along the St. Lucie River Estuary in southeastern Florida from 1998 to 2001. The data included for analysis are stage, 15-minute flow, salinity, water temperature, turbidity, and suspended-solids concentration. During the period of record, the estuary experienced a drought, major storm events, and high-water discharge from Lake Okeechobee. Flow mainly occurred through the South Fork of the St. Lucie River; however, when flow increased through control structures along the C-23 and C-24 Canals, the North Fork was a larger than usual contributor of total freshwater inflow to the estuary. At one tidal site (Steele Point), the majority of flow was southward toward the St. Lucie Inlet; at a second tidal site (Indian River Bridge), the majority of flow was northward into the Indian River Lagoon. Large-volume stormwater discharge events greatly affected the St. Lucie River Estuary. Increased discharge typically was accompanied by salinity decreases that resulted in water becoming and remaining fresh throughout the estuary until the discharge events ended. Salinity in the estuary usually returned to prestorm levels within a few days after the events. Turbidity decreased and salinity began to increase almost immediately when the gates at the control structures closed. Salinity ranged from less than 1 to greater than 35 parts per thousand during the period of record (1998-2001), and typically varied by several parts per thousand during a tidal cycle. Suspended-solids concentrations were observed at one canal site (S-80) and two tidal sites (Speedy Point and Steele Point) during a discharge event in April and May 2000. Results suggest that most deposition of suspended-solids concentration occurs between S-80 and Speedy Point. The turbidity data collected also support this interpretation. The ratio of inorganic to organic suspended-solids concentration observed at S-80, Speedy Point, and Steele Point

  15. Brazil The Duck Lagoon

    Science.gov (United States)

    2002-01-01

    This Multi-angle Imaging SpectroRadiometer (MISR) image of Brazil covers an area of about 298 kilometers x 358 kilometers, and was captured by the instrument's vertical-viewing (nadir) camera on December 27, 2001. The 'Lagoa dos Patos', in the Brazilian state of Rio Grande do Sul, translates to 'the Duck Lagoon'. It was named by 16th century Jesuit settlers, who asked the King of Spain to grant them title to the lagoon so that they could breed ducks. The King consented, but revoked his edict when he discovered that the 'duck-pond' (measuring about 14,000 square kilometers) was one of the largest lagoonal systems in the world. Note the sediment plume emanating from the southern end of the lagoon. Sailors in the 16th century imagined this outlet to be the mouth of a large river. Early Portuguese explorers mistook the entrance to the lagoon for the mouth of a great river and called it the Rio Grande. A series of wave-like points and curls form 'cusps' on the inner shores of the lagoon. The lagoon's characteristics change with short-term tide-induced cyclic perturbations, and with longer term large scale meteorological conditions. The distinctive wavelike 'cusps' along the inner shores result from the circulation, erosion and accumulation of sediments driven by wind and tidal action. The El Nino Southern Oscillation (ENSO) circulation affects precipitation amount and continental runoff, thereby changing the contents of the lagoon waters. High rainfall and increased freshwater discharge during El Nino events correspond with elevated dissolved nutrient concentrations and increased phytoplankton growth. La Nina years are dry and the associated low rainfall reduces the freshwater recharge to the lagoon, causing an increase in salinity. Occasional blooms of toxic cyanobacteria (Microcystis aeruginosa), have been registered in the lagoon when nutrient concentrations are elevated. A number of reeds and grasses are important to the lagoon estuary, including widgeon grass

  16. Estuarine River Data for the Ten Thousand Islands Area, Florida, Water Year 2005

    Science.gov (United States)

    Byrne, Michael J.; Patino, Eduardo

    2008-01-01

    The U.S. Geological Survey collected stream discharge, stage, salinity, and water-temperature data near the mouths of 11 tributaries flowing into the Ten Thousand Islands area of Florida from October 2004 to June 2005. Maximum positive discharge from Barron River and Faka Union River was 6,000 and 3,200 ft3/s, respectively; no other tributary exceeded 2,600 ft3/s. Salinity variation was greatest at Barron River and Faka Union River, ranging from 2 to 37 ppt, and from 3 to 34 ppt, respectively. Salinity maximums were greatest at Wood River and Little Wood River, each exceeding 40 ppt. All data were collected prior to the commencement of the Picayune Strand Restoration Project, which is designed to establish a more natural flow regime to the tributaries of the Ten Thousand Islands area.

  17. Changes in the fish fauna of the Kissimmee River basin, peninsular Florida: Nonnative additions

    Science.gov (United States)

    Nico, L.G.

    2005-01-01

    Recent decades have seen substantial changes in fish assemblages in rivers of peninsular Florida. The most striking change has involved the addition of nonnative fishes, including taxa from Asia, Africa, and Central and South America. I review recent and historical records of fishes occurring in the Kissimmee River basin (7,800 km2), a low-gradient drainage with 47 extant native fishes (one possibly the result of an early transplant), at least 7 foreign fishes (most of which are widely established), and a stocked hybrid. Kissimmee assemblages include fewer marine fishes than the nearby Peace and Caloosahatchee rivers, and fewer introduced foreign fishes than south Florida canals. Fish assemblages of the Kissimmee and other subtropical Florida rivers are dynamic, due to new introductions, range expansions of nonnative fishes already present, and periodic declines in nonnative fish populations during occasional harsh winters. The addition, dispersal, and abundance of nonnative fishes in the basin is linked to many factors, including habitat disturbance, a subtropical climate, and the fact that the basin is centrally located in a region where drainage boundaries are blurred and introductions of foreign fishes commonplace. The first appearance of foreign fishes in the basin coincided with the complete channelization of the Kissimmee River in the 1970s. Although not a causal factor, artificial waterways connecting the upper lakes and channelization of the Kissimmee River have facilitated dispersal. With one possible exception, there have been no basin-wide losses of native fishes. When assessing change in peninsular Florida waters, extinction or extirpation of fishes appears to be a poor measure of impact. No endemic species are known from peninsular Florida (although some endemic subspecies have been noted). Most native freshwater fishes are themselves descended from recent invaders that reached the peninsula from the main continent. These invasions likely were

  18. Untangling Trends and Drivers of Changing River Discharge Along Florida's Gulf Coast

    Science.gov (United States)

    Glodzik, K.; Kaplan, D. A.; Klarenberg, G.

    2017-12-01

    Along the relatively undeveloped Big Bend coastline of Florida, discharge in many rivers and springs is decreasing. The causes are unclear, though they likely include a combination of groundwater extraction for water supply, climate variability, and altered land use. Saltwater intrusion from altered freshwater influence and sea level rise is causing transformative ecosystem impacts along this flat coastline, including coastal forest die-off and oyster reef collapse. A key uncertainty for understanding river discharge change is predicting discharge from rainfall, since Florida's karstic bedrock stores large amounts of groundwater, which has a long residence time. This study uses Dynamic Factor Analysis (DFA), a multivariate data reduction technique for time series, to find common trends in flow and reveal hydrologic variables affecting flow in eight Big Bend rivers since 1965. The DFA uses annual river flows as response time series, and climate data (annual rainfall and evapotranspiration by watershed) and climatic indices (El Niño Southern Oscillation [ENSO] Index and North Atlantic Oscillation [NAO] Index) as candidate explanatory variables. Significant explanatory variables (one evapotranspiration and three rainfall time series) explained roughly 50% of discharge variation across rivers. Significant trends (representing unexplained variation) were shared among rivers, with geographical grouping of five northern rivers and three southern rivers, along with a strong downward trend affecting six out of eight systems. ENSO and NAO had no significant impact. Advancing knowledge of these dynamics is necessary for forecasting how altered rainfall and temperatures from climate change may impact flows. Improved forecasting is especially important given Florida's reliance on groundwater extraction to support its growing population.

  19. Sources of dissolved inorganic nitrogen in a coastal lagoon adjacent to a major metropolitan area, Miami Florida (USA)

    International Nuclear Information System (INIS)

    Swart, Peter K.; Anderson, William T.; Altabet, Mark A.; Drayer, Courtney; Bellmund, Sarah

    2013-01-01

    Highlights: • A range of biota (algae and sea grasses) shows enriched δ 15 N close to the coast. • Enriched signals are evident in the particulate and sedimentary organic material. • δ 15 N signals are correlated with high inputs of dissolved inorganic matter. • The enriched values support the presence of a sewage related component. • The δ 15 N could arise from the local landfill, injected wastewater, or septic systems. - Abstract: Between 2006 and 2007, a study was carried out to determine the relative importance of natural and anthropogenic input of nitrogen into Biscayne Bay (South Florida, USA) using δ 13 C and δ 15 N values of algae, seagrasses, and particulate organic material, δ 18 O and δ 15 N of the NO 3 - and δ 13 C of the dissolved inorganic carbon. The δ 15 N values of all components showed a strong east to west gradient approaching more positive values (+7 to +10‰) close to the land-sea interface. The nitrogen could have emanated from the local waste water treatment plant, septic systems within the region, or nitrogen which had been affected by denitrification and leached from the local landfill, wastewater which had been injected into the Floridan aquifer and leaked back to the surface, and/or some other as yet unidentified source. The measured NO 3 - δ 15 N and δ 18 O values indicated that the dissolved nitrate originated from anthropogenic sources and was fractionated during assimilation

  20. Variation in the hindgut microbial communities of the Florida manatee, Trichechus manatus latirostris over winter in Crystal River, Florida

    Science.gov (United States)

    Merson, Samuel D.; Ouwerkerk, Diane; Gulino, Lisa-Maree; Klieve, Athol; Bonde, Robert K.; Burgess, Elizabeth A.; Lanyon, Janet M.

    2014-01-01

    The Florida manatee, Trichechus manatus latirostris, is a hindgut-fermenting herbivore. In winter, manatees migrate to warm water overwintering sites where they undergo dietary shifts and may suffer from cold-induced stress. Given these seasonally induced changes in diet, the present study aimed to examine variation in the hindgut bacterial communities of wild manatees overwintering at Crystal River, west Florida. Faeces were sampled from 36 manatees of known sex and body size in early winter when manatees were newly arrived and then in mid-winter and late winter when diet had probably changed and environmental stress may have increased. Concentrations of faecal cortisol metabolite, an indicator of a stress response, were measured by enzyme immunoassay. Using 454-pyrosequencing, 2027 bacterial operational taxonomic units were identified in manatee faeces following amplicon pyrosequencing of the 16S rRNA gene V3/V4 region. Classified sequences were assigned to eight previously described bacterial phyla; only 0.36% of sequences could not be classified to phylum level. Five core phyla were identified in all samples. The majority (96.8%) of sequences were classified as Firmicutes (77.3 ± 11.1% of total sequences) or Bacteroidetes (19.5 ± 10.6%). Alpha-diversity measures trended towards higher diversity of hindgut microbiota in manatees in mid-winter compared to early and late winter. Beta-diversity measures, analysed through permanova, also indicated significant differences in bacterial communities based on the season.

  1. Diversions of the Ribeira river flow and their Influence on Sediment Supply in the Cananeia-Iguape Estuarine-Lagoonal System (SE Brazil)

    Science.gov (United States)

    Cornaggia, Flaminia; Jovane, Luigi; Alessandretti, Luciano; Alves de Lima Ferreira, Paulo; Lopes Figueira, Rubens C.; Rodelli, Daniel; Bueno Benedetti Berbel, Gláucia; Braga, Elisabete S.

    2018-04-01

    The Cananéia-Iguape system is a combined estuarine-lagoonal sedimentary system, located along the SE coast of Brazil. It consists of a network of channels and islands oriented mainly parallel to the coast. About 165 years ago, an artificial channel, the Valo Grande, was opened in the northern part of this system to connect a major river of the region, the Ribeira River, to the estuarine-lagoon complex. The Valo Grande was closed with a dam and re-opened twice between 1978 and 1995, when it was finally left open. These openings and closures of the Valo Grande had a significant influence on the Cananéia-Iguape system. In this study we present mineralogical, chemical, palaeomagnetic, and geochronological data from a sediment core collected at the southern end of the 50-km long lagoonal system showing how the phases of the opening and closure of the channel through time are expressed in the sedimentary record. Despite the homogeneity of the grain size and magnetic properties throughout the core, significant variations in the mineralogical composition showed the influence of the opening of the channel on the sediment supply. Less mature sediment, with lower quartz and halite and higher kaolinite, brucite, and franklinite, corresponded to periods when the Valo Grande was open. On the other hand, higher abundance of quartz and halite, as well as the disappearance of other detrital minerals, corresponded with periods of absence or closure of the channel, indicating a more sea-influenced depositional setting. This work represented an example of anthropogenic influence in a lagoonal-estuarine sedimentary system, which is a common context along the coast of Brazil.

  2. Hydrochemical evidence for mixing of river water and groundwater during high-flow conditions, lower Suwannee River basin, Florida, USA

    Science.gov (United States)

    Crandall, C.A.; Katz, B.G.; Hirten, J.J.

    1999-01-01

    Karstic aquifers are highly susceptible to rapid infiltration of river water, particularly during periods of high flow. Following a period of sustained rainfall in the Suwannee River basin, Florida, USA, the stage of the Suwannee River rose from 3.0 to 5.88 m above mean sea level in April 1996 and discharge peaked at 360 m3/s. During these high-flow conditions, water from the Suwannee River migrated directly into the karstic Upper Floridan aquifer, the main source of water supply for the area. Changes in the chemical composition of groundwater were quantified using naturally occurring geochemical tracers and mass-balance modeling techniques. Mixing of river water with groundwater was indicated by a decrease in the concentrations of calcium, silica, and 222Rn; and by an increase in dissolved organic carbon (DOC), tannic acid, and chloride, compared to low-flow conditions in water from a nearby monitoring well, Wingate Sink, and Little River Springs. The proportion (fraction) of river water in groundwater ranged from 0.13 to 0.65 at Wingate Sink and from 0.5 to 0.99 at well W-17258, based on binary mixing models using various tracers. The effectiveness of a natural tracer in quantifying mixing of river water and groundwater was related to differences in tracer concentration of the two end members and how conservatively the tracer reacted in the mixed water. Solutes with similar concentrations in the two end-member waters (Na, Mg, K, Cl, SO4, SiO2) were not as effective tracers for quantifying mixing of river water and groundwater as those with larger differences in end-member concentrations (Ca, tannic acid, DOC, 222Rn, HCO3). ?? Springer-Verlag.

  3. Molecular composition and bioavailability of dissolved organic nitrogen in a lake flow-influenced river in south Florida, USA

    Science.gov (United States)

    Dissolved organic nitrogen (DON) represents a large percentage of the total nitrogen in rivers and estuaries, and can contribute to coastal eutrophication and hypoxia. This study reports on the composition and bioavailability of DON along the Caloosahatchee River (Florida), a heavily managed system ...

  4. Seasonal fluctuation of some limnological variables on a floodplain lake (Patos lagoon of the Upper Paraná River, Mato Grosso do Sul State, Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigues Luzia Cleide

    2002-01-01

    Full Text Available Temporal variations of some limnological variables in limnetic and littoral regions of Patos lagoon, a "várzea" lake on the floodplain of the Upper Paraná River (22(0 43'12"S e 53(0 17'37"W, were studied in relation to hydrological and climatological factors. Measurements of water temperature, euphotic zone, suspended material, electrical conductivity, total alkalinity, pH, dissolved oxygen, carbon dioxide, total nitrogen, total Kjeldahl nitrogen, total phosphorus, dissolved phosphorus, reactive soluble phosphorus and chlorophyll a were taken monthly between March 1993 and February 1994. Results lend evidence to the importance of the hydrological regime on the dynamic of limnological variables in floodplain lakes. A dilution of nutrients in the lagoon, especially phosphates, occurred during floods. This was followed by fertilization of the environment by nutrients from the inundated marginal regions. During low connectivity periods, autochthonous, events such as ressuspension of sediment, brought on by wind and rain, governed limnological events in the lagoon.

  5. Surface-Water and Groundwater Interactions along the Withlacoochee River, West-Central Florida

    Science.gov (United States)

    Trommer, J.T.; Yobbi, D.K.; McBride, W.S.

    2009-01-01

    A study of the Withlacoochee River watershed in west-central Florida was conducted from October 2003 to March 2007 to gain a better understanding of the hydrology and surface-water and groundwater interactions along the river. The Withlacoochee River originates in the Green Swamp area in north-central Polk County and flows northerly through seven counties, emptying into the Gulf of Mexico. This study includes only the part of the watershed located between the headwaters in the Green Swamp and the U.S. Geological Survey gaging station near Holder, Florida. The Withlacoochee River within the study area is about 108 miles long and drains about 1,820 square miles. The Withlacoochee River watershed is underlain by thick sequences of carbonate rock that are covered by thin surficial deposits of unconsolidated sand and sandy clay. The clay layer is breached in many places because of the karst nature of the underlying limestone, and the degree of confinement between the Upper Florida aquifer and the surficial aquifer is highly variable throughout the watershed. The potential for movement of water from the surface or shallow deposits to deeper deposits, or from deeper deposits to the shallow deposits, exists throughout the Withlacoochee River watershed. Water levels were higher in deeper Upper Floridan aquifer wells than in shallow Upper Floridan aquifer wells or surficial aquifer wells at 11 of 19 paired or nested well sites, indicating potential for discharge to the surface-water system. Water levels were higher in shallow Upper Floridan aquifer or surficial aquifer wells than in deeper Upper Floridan aquifer wells at five other sites, indicating potential for recharge to the deeper Upper Floridan aquifer. Water levels in the surficial aquifer and Upper Floridan aquifer wells at the remaining three sites were virtually the same, indicating little or no confinement at the sites. Potentiometric-surface maps of the Upper Floridan aquifer indicate the pattern of groundwater

  6. Hydrobiological characteristics of Shark River estuary, Everglades National Park, Florida

    Science.gov (United States)

    McPherson, B.F.

    1970-01-01

    Water quality in the Shark River estuary was strongly influenced by seasonal patterns of rainfall, water level and temperature. During the rainy season (summer and early fall) the salinity in the 20-mile long estuary ranged from that of fresh water to half that of sea water while concentrations of dissolved oxygen were low, 2-5 milligrams per liter (mg/l) presumably because, among other factors, microbial activity and respiration were accelerated by high temperatures (30-33 degrees C). During the dry season (late fall through spring) the salinity ranged from 18 grams per liter (g/l) in the headwaters to 36 g/l at the Gulf during a dry year such as 1967 and from 1 to 25 g/l during a wet year such as 1969. Concentrations of dissolved oxygen increased from 2-3 mg/l in the summer of 1967 to 4-7 mg/l in the winter of 1968, and temperature decreased from an average of about 30 degrees C in summer to 20 degrees C in winter. Water level declined 5 to 10 decimeters in the headwaters during the dry season, and salinity and tidal action increased. Large amounts of submerged vegetation died in some headwater creeks at the end of the dry season, presumably killed by salinities above 3 g/l. The decaying organic matter and the decrease in photosynthesis resulted in low dissolved oxygen (1-2 mg/l). Fish died at this time probably as a result of the low dissolved oxygen. Trace elements, heavy metals and insecticides occurred in the waters of the estuary in concentrations below those indicated as harmful for aquatic life by current standards established by the Federal Water Pollution Control Administration (1968). The insecticides detected were concentrated in sediment and in various organisms. The patterns of distribution of planktonic and small nektonic animals in the estuary were related to salinity. Copepods (Arcatia tonsa, Labidocera aestiva, Pseudodiaptomus coronatus), cumaceans (Cyclaspis sp.), chaetognaths (Sagitta hispida), bay anchovies (Anchoa mitchilli), and scaled

  7. Importance of floodplain connectivity to fish populations in the Apalachicola River, Florida

    Science.gov (United States)

    Burgess, O.T.; Pine, William E.; Walsh, S.J.

    2013-01-01

    Floodplain habitats provide critical spawning and rearing habitats for many large-river fishes. The paradigm that floodplains are essential habitats is often a key reason for restoring altered rivers to natural flow regimes. However, few studies have documented spatial and temporal utilization of floodplain habitats by adult fish of sport or commercial management interest or assessed obligatory access to floodplain habitats for species' persistence. In this study, we applied telemetry techniques to examine adult fish movements between floodplain and mainstem habitats, paired with intensive light trap sampling of larval fish in these same habitats, to assess the relationships between riverine flows and fish movement and spawning patterns in restored and unmodified floodplain distributaries of the Apalachicola River, Florida. Our intent is to inform resource managers on the relationships between the timing, magnitude and duration of flow events and fish spawning as part of river management actions. Our results demonstrate spawning by all study species in floodplain and mainstem river habitat types, apparent migratory movements of some species between these habitats, and distinct spawning events for each study species on the basis of fish movement patterns and light trap catches. Additionally, Micropterus spp., Lepomis spp. and, to a lesser degree, Minytrema melanops used floodplain channel habitat that was experimentally reconnected to the mainstem within a few weeks of completing the restoration. This result is of interest to managers assessing restoration activities to reconnect these habitats as part of riverine restoration programmes globally.

  8. Export of materials along a tidal river channel that links a coastal lagoon to the adjacent sea

    Directory of Open Access Journals (Sweden)

    Javier Aldeco Ramírez

    2012-09-01

    Full Text Available Intratidal variability and flux of salt, chlorophyll-a and suspended materials were evaluated in a shallow tropical tidal channel linking a coastal lagoon to the western Gulf of Mexico. Velocity, temperature and conductivity were used to calculate the fluxes. Data were recorded during three tidal velocity cycles (tvc under extreme river discharge conditions. Chlorophyll-a and suspended materials were determined below the surface. In both seasons (dry and rainy, the flow was ebb-dominated and with longer duration than when in flood. Maximum current velocities were 0.30 m s-1 in May (dry season and 0.60 m s-1 in September (rainy season. In the dry season the mean chlorophyll-a export was of 7.56 Kg over tvc while the import was of 3.32 Kg. In the rainy season mean export (47.3 Kg was 6 times greater than the import (7.93 Kg over tvc. Phytoplankton was dominated by organisms of marine origin. The mean of exported, suspended materials in the rainy season (111.3 Kg was 4.6 times greater (859 Kg than that in the dry season (184.7 Kg over tvc. Tidal velocity asymmetry is an effective mechanism of exportation, introducing relatively warm and saltier water into the river through the tidal channel.A variabilidade intramaré, o fluxo de salinidade, a clorofila-a e material em suspensão foram avaliados em um canal superficial de maré tropical em uma lagoa costeira ao oeste do Golfo do México. Os dados de velocidade, temperatura e condutividade foram usados para cálculo dos fluxos durante três ciclos de velocidades das marés (tvc sob condições extremas de descarga. A Clorofila-a e material em suspensão foram determinados abaixo em subsuperfície. Em ambas as estações (seca e chuvosa, o fluxo dominante foi durante o refluxo e com duração maior durante o fluxo de entrada. A máxima velocidade encontrada foi 0.30 m s-1 em maio (estação seca e 0.60 m s-1 em setembro (estação chuvosa. Durante a época seca foram exportadas 7.56 Kg de clorofila

  9. Hydrograph simulation models of the Hillsborough and Alafia Rivers, Florida: a preliminary report

    Science.gov (United States)

    Turner, James F.

    1972-01-01

    Mathematical (digital) models that simulate flood hydrographs from rainfall records have been developed for the following gaging stations in the Hillsborough and Alafia River basins of west-central Florida: Hillsborough River near Tampa, Alafia River at Lithia, and north Prong Alafia River near Keysville. These models, which were developed from historical streamflow and and rainfall records, are based on rainfall-runoff and unit-hydrograph procedures involving an arbitrary separation of the flood hydrograph. These models assume the flood hydrograph to be composed of only two flow components, direct (storm) runoff, and base flow. Expressions describing these two flow components are derived from streamflow and rainfall records and are combined analytically to form algorithms (models), which are programmed for processing on a digital computing system. Most Hillsborough and Alafia River flood discharges can be simulated with expected relative errors less than or equal to 30 percent and flood peaks can be simulated with average relative errors less than 15 percent. Because of the inadequate rainfall network that is used in obtaining input data for the North Prong Alafia River model, simulated peaks are frequently in error by more than 40 percent, particularly for storms having highly variable areal rainfall distribution. Simulation errors are the result of rainfall sample errors and, to a lesser extent, model inadequacy. Data errors associated with the determination of mean basin precipitation are the result of the small number and poor areal distribution of rainfall stations available for use in the study. Model inadequacy, however, is attributed to the basic underlying theory, particularly the rainfall-runoff relation. These models broaden and enhance existing water-management capabilities within these basins by allowing the establishment and implementation of programs providing for continued development in these areas. Specifically, the models serve not only as a

  10. Satellite Derived Water Quality Observations Are Related to River Discharge and Nitrogen Loads in Pensacola Bay, Florida

    OpenAIRE

    John C. Lehrter; John C. Lehrter; Chengfeng Le

    2017-01-01

    Relationships between satellite-derived water quality variables and river discharges, concentrations and loads of nutrients, organic carbon, and sediments were investigated over a 9-year period (2003–2011) in Pensacola Bay, Florida, USA. These analyses were conducted to better understand which river forcing factors were the primary drivers of estuarine variability in several water quality variables. Remote sensing reflectance time-series data were retrieved from the MEdium Resolution Imaging ...

  11. 78 FR 79709 - Duke Energy Florida, Inc., Crystal River Unit 3 Nuclear Generating Plant Post-Shutdown...

    Science.gov (United States)

    2013-12-31

    ... NUCLEAR REGULATORY COMMISSION [Docket No. 50-302; NRC-2013-0283] Duke Energy Florida, Inc., Crystal River Unit 3 Nuclear Generating Plant Post-Shutdown Decommissioning Activities Report AGENCY: Nuclear Regulatory Commission (NRC). ACTION: Notice of receipt; availability; public meeting; and request...

  12. CDOM Distribution and Dynamics in a Mangrove Ecosystem along the Shark River, Florida Everglades

    Science.gov (United States)

    Andrew, A. A.; del Castillo, C. E.

    2016-02-01

    Mangrove forests, a fraction of tropical forest, are in general a disproportionately important component in the global carbon cycle. Mangroves are highly productive, sequestering CO2 at rates higher than many other ecosystems, however more than half of this fixed carbon cannot be accounted for. Additionally, as they sit at the intersection of land and ocean, it's hypothesized that a large fraction of DOC transformations occur in these ecosystems and represent a major sink of terrigenous DOM. These factors highlight the importance of understanding mangrove environments in terms of DOM optical signals as well as reactivity upon light absorption. Here, we present the CDOM dynamics and distribution for a mangrove ecosystem in the Shark River, along the Southwest coast of Florida, part of the largest contiguous mangrove forest in North America. Station sampling of the study area occurred over 4 cruises, approximately one week in length: October 2014, March 2015, July 2015 and September 2015. Most of the stations were along the Shark River, with a smaller number in the vicinity of Tarpon bay and Harney River. Optical measurements of CDOM absorption and fluorescence, fluorescence quantum yields, DOC and spectral slope were obtained for over 70 stations in the study area. The spatial distribution of these optical properties are presented including their relation to salinity and tidal patterns in the study area. Additionally, we present the wavelength dependent quantum photoproduction efficiencies of DIC obtained via irradiation experiments of selective samples in the study area.

  13. From channelization to restoration: Sociohydrologic modeling with changing community preferences in the Kissimmee River Basin, Florida

    Science.gov (United States)

    Chen, Xi; Wang, Dingbao; Tian, Fuqiang; Sivapalan, Murugesu

    2016-02-01

    The Kissimmee River Basin (Florida, USA) underwent river channelization in the 1960s and subsequent restoration in the 1990s, revealing a shift in management emphasis from flood protection to wetland health. In this paper, this shift is hypothesized to result from changing human values and preferences, and a power differential between the more numerous and affluent upstream urban residents (who prioritize wetland restoration) and downstream rural residents (who prioritize flood protection). We develop a conceptual sociohydrologic model to simulate the interactions between community interests and hydrology. The modeling results show that flood intensity decreased after channelization, which reduced concern about flooding. However, channelization also led to a decrease in wetland storage, which caused an increase of wetland concern, especially among the urban residents. Eventually, the community sensitivity switched from favoring flood protection to favoring wetlands, and subsequent management strategies switched from channelization to restoration. Using the model, we project that the wetlands will be recovering for the next 20 years and community sensitivity will slowly go back to a neutral state. However, possible rainfall intensification in the future could return the community sensitivity to favoring flood protection again. The preferential increase of upstream population growth will raise the community's concern about wetlands and the preferential increase of downstream population growth will magnify concern about flooding. This study provides insight into the driving forces behind human-water interactions in the Kissimmee River Basin while simultaneously demonstrating the potential of sociohydrologic modeling to describe complex human-water coupled systems with simple concepts and equations.

  14. Phase I of the Kissimmee River restoration project, Florida, USA: impacts of construction on water quality.

    Science.gov (United States)

    Colangelo, David J; Jones, Bradley L

    2005-03-01

    Phase I of the Kissimmee River restoration project included backfilling of 12 km of canal and restoring flow through 24 km of continuous river channel. We quantified the effects of construction activities on four water quality parameters (turbidity, total phosphorus flow-weighted concentration, total phosphorus load and dissolved oxygen concentration). Data were collected at stations upstream and downstream of the construction and at four stations within the construction zone to determine if canal backfilling and construction of 2.4 km of new river channel would negatively impact local and downstream water quality. Turbidity levels at the downstream station were elevated for approximately 2 weeks during the one and a half year construction period, but never exceeded the Florida Department of Environmental Protection construction permit criteria. Turbidity levels at stations within the construction zone were high at certain times. Flow-weighted concentration of total phosphorus at the downstream station was slightly higher than the upstream station during construction, but low discharge limited downstream transport of phosphorus. Total phosphorus loads at the upstream and downstream stations were similar and loading to Lake Okeechobee was not significantly affected by construction. Mean water column dissolved oxygen concentrations at all sampling stations were similar during construction.

  15. Sources of nitrate in water from springs and the Upper Floridan aquifer, Suwannee River basin, Florida

    Science.gov (United States)

    Katz, B.G.; Hornsby, H.D.; Böhlke, John Karl

    1999-01-01

    In the Suwannee River basin of northern Florida, nitrate-N concentrations are 1.5 to 20 mg 1-1 in waters of the karstic Upper Floridan aquifer and in springs that discharge into the middle reach of the Suwannee River. During 1996-1997, fertilizers and animal wastes from farming operations in Suwannee County contributed approximately 49% and 45% of the total N input, respectively. Values of ??15N-NO3 in spring waters range from 3.9??? to 5.8???, indicating that nitrate most likely originates from a mixture of inorganic (fertilizers) and organic (animal waste) sources. In Lafayette County, animal wastes from farming operations and fertilizers contributed approximately 53% and 39% of the total N input, respectively, but groundwater near dairy and poultry farms has ??15N-NO3 values of 11.0-12.1???, indicative of an organic source of nitrate. Spring waters that discharge to the Suwannee River from Lafayette County have ??15N-NO3 values of 5.4-8.39???, which are indicative of both organic and inorganic sources. Based on analyses of CFCs, the mean residence time of shallow groundwater and spring water ranges between 8-12 years and 12-25 years, respectively.

  16. Stability and spatio-temporal structure in fish assemblages of two floodplain lagoons of the lower Orinoco River

    Directory of Open Access Journals (Sweden)

    Nirson González

    Full Text Available Fish assemblage structure and variability were analyzed in two floodplain lagoons (Las Arhuacas and Los Cardonales along the lower Orinoco over a hydrological cycle. Every three months during continuous three-day sampling, experimental gill nets (5 to 12.5 cm of mesh opening and 1 mm-mesh seine nets were utilized according to the types of habitats presents. A total of 133 fish species were found in Las Arhuacas and 95 species in Cardonales. Fifty five and 17 species were exclusive to Las Arhuacas and Los Cardonales respectively, and 77 were common to both lagoons. In Las Arhuacas, the most speciesrich orders were Characiformes, Siluriformes, Perciformes and Gymnotiformes and in Los Cardonales, the most species-rich orders were Characiformes, Siluriformes, Clupeiformes and Perciformes. The richness, abundance and biomass were significantly higher (p < 0.001 in Arhuacas than in Cardonales. In general, the fishes assemblage was highly variable during the high water phase and moderately stable during low water phase in both lagoons, with more stability or less variability in Cardonales than Arhuacas. Also, there were significant differences in the fish assemblages between the two lagoons, mainly during low waters (ANOSIM; p < 0.001. The species that contributed most to the mean dissimilarity between the lagoons were Hypostomus argus, Aphanotorulus ammophilus, Potamorhina altamazonica, Prochilodus mariae, Loricaria gr. cataphracta, Oxydoras sifontesi, Hydrolycus armatus, Hyphopthalmus edentatus and Pterodoras rivasi. The last four species were more commonly collected in Los Cardonales. Also, the species of small size (mainly SL < 5 cm such as Rhinosardinia amazonica, Moenkhausia sp. 1 "lepidura", Moenkhausia sp. 2, Aphyocharax alburnus, Characidium sp. 1, Moenkhausia sp. 3, Exodon paradoxus and Roeboides dientonito contributed to the mean dissimilarity among the beach and aquatic vegetation habitats. The patterns of the species assemblage

  17. Standing crop and aboveground biomass partitioning of a dwarf mangrove forest in Taylor River Slough, Florida

    Science.gov (United States)

    Coronado-Molina, C.; Day, J.W.; Reyes, E.; Perez, B.C.

    2004-01-01

    The structure and standing crop biomass of a dwarf mangrove forest, located in the salinity transition zone ofTaylor River Slough in the Everglades National Park, were studied. Although the four mangrove species reported for Florida occurred at the study site, dwarf Rhizophora mangle trees dominated the forest. The structural characteristics of the mangrove forest were relatively simple: tree height varied from 0.9 to 1.2 meters, and tree density ranged from 7062 to 23 778 stems haa??1. An allometric relationship was developed to estimate leaf, branch, prop root, and total aboveground biomass of dwarf Rhizophora mangle trees. Total aboveground biomass and their components were best estimated as a power function of the crown area times number of prop roots as an independent variable (Y = B ?? Xa??0.5083). The allometric equation for each tree component was highly significant (pRhizophora mangle contributed 85% of total standing crop biomass. Conocarpus erectus, Laguncularia racemosa, and Avicennia germinans contributed the remaining biomass. Average aboveground biomass allocation was 69% for prop roots, 25% for stem and branches, and 6% for leaves. This aboveground biomass partitioning pattern, which gives a major role to prop roots that have the potential to produce an extensive root system, may be an important biological strategy in response to low phosphorus availability and relatively reduced soils that characterize mangrove forests in South Florida.

  18. Environmental Nitrogen Losses from Commercial Crop Production Systems in the Suwannee River Basin of Florida.

    Science.gov (United States)

    Prasad, Rishi; Hochmuth, George J

    2016-01-01

    The springs and the Suwannee river of northern Florida in Middle Suwanee River Basin (MSRB) are among several examples in this planet that have shown a temporal trend of increasing nitrate concentration primarily due to the impacts of non-point sources such as agriculture. The rate of nitrate increase in the river as documented by Ham and Hatzell (1996) was 0.02 mg N L-1 y-1. Best management practices (BMPs) for nutrients were adopted by the commercial farms in the MSRB region to reduce the amounts of pollutants entering the water bodies, however the effectiveness of BMPs remains a topic of interest and discussion among the researchers, environmental administrators and policy makers about the loads of nitrogen entering into groundwater and river systems. Through this study, an initiative was taken to estimate nitrogen losses into the environment from commercial production systems of row and vegetable crops that had adopted BMPs and were under a presumption of compliance with state water quality standards. Nitrogen mass budget was constructed by quantifying the N sources and sinks for three crops (potato (Solanum tuberosum L.), sweet corn (Zea mays L.) and silage corn (Zea mays L.)) over a four year period (2010-2013) on a large representative commercial farm in northern Florida. Fertilizer N was found to be the primary N input and represented 98.0 ± 1.4, 91.0 ± 13.9, 78.0 ± 17.3% of the total N input for potato, sweet corn, and silage corn, respectively. Average crop N uptake represented 55.5%, 60.5%, and 65.2% of the mean total input N whereas average mineral N left in top 0.3 m soil layer at harvest represented 9.1%, 4.5%, and 2.6% of the mean total input N. Mean environmental N losses represented 35.3%, 34.3%, and 32.7% of the mean total input N for potato, sweet corn, and silage corn, respectively. Nitrogen losses showed a linear trend with increase in N inputs. Although, there is no quick fix for controlling N losses from crop production in MSRB, the

  19. ESTABLISHING MINIMUM FLOWS AND LEVELS OF FRESHWATER IN THE CALOOSAHATCHEE RIVER, FLORIDA, USING RESPONSES OF OYSTERS.

    Science.gov (United States)

    Alterations in freshwater inflow resulting from watershed development and water management practices have impacted salinity and water quality and led to declines in oyster populations within southwest Florida estuaries. In the Caloosahatchee Estuary, Florida watershed management ...

  20. 2005/2006 Southwest Florida Water Management District (SWFWMD) Lidar: Peace River South (including Carter Creek)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) LAS dataset is a survey of select areas within Southwest Florida. These data were produced for the Southwest Florida Water...

  1. Water use in the Apalachicola-Chattahoochee-Flint River Basin, Alabama, Florida, and Georgia, 2010, and water-use trends, 1985-2010

    Science.gov (United States)

    Lawrence, Stephen J.

    2016-02-25

    The Apalachicola-Chattahoochee-Flint (ACF) River Basin encompasses about 20,230 square miles in parts of Alabama, Florida, and Georgia. Increasing population growth and agricultural production from the 1970s to 2010 has prompted increases in water-resources development and substantially increased water demand in the basin. Since the 1980s, Alabama, Florida, Georgia, and the U.S. Army Corps of Engineers are parties to litigation concerning water management in the ACF River Basin.

  2. Organic matter dynamics in a karstic watershed: Example from Santa Fe River, Florida, USA

    Science.gov (United States)

    Jin, J.; Khadka, M. B.; Martin, J. B.; Zimmerman, A. R.

    2011-12-01

    Organic matter (OM) dynamics in karstic watersheds can involve a range of interactions between organic and inorganic phases of carbon. These interactions include OM remineralization, which will changes its lability, increase dissolved inorganic carbon (DIC) concentrations, reduce pH, and enhance carbonate mineral dissolution. Dissolved organic carbon (DOC) concentrations are elevated in black-water rivers of northern Florida from both allochthonous and autochthonous sources and these rivers flow into and interact with the karstic Floridan Aquifer. One such river, the Santa Fe River, is split into upper confined and lower unconfined watersheds by the Cody Scarp, which represent the erosional edge of a regional confining unit. Water samples were collected from 8 sites across the entire Santa Fe River watershed (SFRW) during 9 sampling trips from December 2009 to May 2011 at flow conditions that ranged from 27 to 39 m3/s, with the highest flow about 45% higher than baseflow. At sites above the Cody Scarp, the river has elevated DOC concentrations, which decrease downstream, while dissolved inorganic carbon (DIC) and δ13C-DIC show opposite trends. At high flow, DOC concentrations progressively decrease downstream from dilution by low-DOC water discharging from the Floridan Aquifer. At low flow, the water chemistry varies little from upstream to downstream, largely because the composition of upstream water becomes similar to that of downstream water. DOC is inversely and linearly correlated with DIC and δ13C-DIC, but the slope of the correlations vary with discharge, with low flow having more negative slopes than high flow. The OM becomes more labile with distance downstream as assessed using two fluorescence indices, biological/autochthonous index (BIX) and humification index (HIX). This increase in lability suggests that DOC is produced in the river, and this production is reflected in a downstream increase in DOC flux regardless of dilution by the influx of low

  3. NOAA Office for Coastal Management Benthic Habitat Data, Apalachicola Bay, Dry Tortugas, Florida Bay, and Indian River Lagoon, Florida, 1991-2001 (NODC Accession 0001045)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are a collection of regional GIS (Arcview shapefiles and associated Federal Geographic Data Committee (FGDC) metadata) benthic habitat files from studies...

  4. Combining L- and X-Band SAR Interferometry to Assess Ground Displacements in Heterogeneous Coastal Environments: The Po River Delta and Venice Lagoon, Italy

    Directory of Open Access Journals (Sweden)

    Luigi Tosi

    2016-04-01

    Full Text Available From leveling to SAR-based interferometry, the monitoring of land subsidence in coastal transitional environments significantly improved. However, the simultaneous assessment of the ground movements in these peculiar environments is still challenging. This is due to the presence of relatively small built-up zones and infrastructures, e.g., coastal infrastructures, bridges, and river embankments, within large natural or rural lands, e.g., river deltas, lagoons, and farmland. In this paper we present a multi-band SAR methodology to integrate COSMO-SkyMed and ALOS-PALSAR images. The method consists of a proper combination of the very high-resolution X-band Persistent Scatterer Interferometry (PSI, which achieves high-density and precise measurements on single structures and constructed areas, with L-band Short-Baseline SAR Interferometry (SBAS, properly implemented to raise its effectiveness in retrieving information in vegetated and wet zones. The combined methodology is applied on the Po River Delta and Venice coastland, Northern Italy, using 16 ALOS-PALSAR and 31 COSMO-SkyMed images covering the period between 2007 and 2011. After a proper calibration of the single PSI and SBAS solution using available GPS records, the datasets have been combined at both the regional and local scales. The measured displacements range from ~0 mm/yr down to −35 mm/yr. The results reveal the variable pattern of the subsidence characterizing the more natural and rural environments without losing the accuracy in quantifying the sinking of urban areas and infrastructures. Moreover, they allow improving the interpretation of the natural and anthropogenic processes responsible for the ongoing subsidence.

  5. Investigation of Submarine Groundwater Discharge along the Tidal Reach of the Caloosahatchee River, Southwest Florida

    Science.gov (United States)

    Reich, Christopher D.

    2010-01-01

    The tidal reach of the Caloosahatchee River is an estuarine habitat that supports a diverse assemblage of biota including aquatic vegetation, shellfish, and finfish. The system has been highly modified by anthropogenic activity over the last 150 years (South Florida Water Management District (SFWMD), 2009). For example, the river was channelized and connected to Lake Okeechobee in 1881 (via canal C-43). Subsequently, three control structures (spillway and locks) were installed for flood protection (S-77 and S-78 in the 1930s) and for saltwater-intrusion prevention (S-79, W.P. Franklin Lock and Dam in 1966). The emplacement of these structures and their impact to natural water flow have been blamed for water-quality problems downstream within the estuary (Flaig and Capece, 1998; SFWMD, 2009). Doering and Chamberlain (1999) found that the operation of these control structures caused large and often rapid variations in salinity during various times of the year. Variable salinities could have deleterious impacts on the health of organisms in the Caloosahatchee River estuary. Flow restriction along the Caloosahatchee has also been linked to surface-water eutrophication problems (Doering and Chamberlain, 1999; SFWMD, 2009) and bottom-sediment contamination (Fernandez and others, 1999). Sources of nutrients (nitrogen and phosphorous) that cause eutrophication are primarily from residential sources and agriculture, though wastewater-treatment-plant discharges can also play a major role (SFWMD, 2009). The pathway for many of these nutrients is by land runoff and direct discharge from stormwater drains. An often overlooked source of nutrients and other chemical constituents is from submarine groundwater discharge (SGD). SGD can be either a diffuse or point source (for example, submarine springs) of nutrients and other chemical constituents to coastal waters (Valiela and others, 1990; Swarzenski and others, 2001; 2006; 2007; 2008). SGD can be composed of either fresh or

  6. Simulation of Regional Ground-Water Flow in the Suwannee River Basin, Northern Florida and Southern Georgia

    Science.gov (United States)

    Planert, Michael

    2007-01-01

    The Suwannee River Basin covers a total of nearly 9,950 square miles in north-central Florida and southern Georgia. In Florida, the Suwannee River Basin accounts for 4,250 square miles of north-central Florida. Evaluating the impacts of increased development in the Suwannee River Basin requires a quantitative understanding of the boundary conditions, hydrogeologic framework and hydraulic properties of the Floridan aquifer system, and the dynamics of water exchanges between the Suwannee River and its tributaries and the Floridan aquifer system. Major rivers within the Suwannee River Basin are the Suwannee, Santa Fe, Alapaha, and Withlacoochee. Four rivers west of the Suwannee River are the Aucilla, the Econfina, the Fenholloway, and the Steinhatchee; all drain to the Gulf of Mexico. Perhaps the most notable aspect of the surface-water hydrology of the study area is that large areas east of the Suwannee River are devoid of channelized, surface drainage; consequently, most of the drainage occurs through the subsurface. The ground-water flow system underlying the study area plays a critical role in the overall hydrology of this region of Florida because of the dominance of subsurface drain-age, and because ground-water flow sustains the flow of the rivers and springs. Three principal hydrogeologic units are present in the study area: the surficial aquifer system, the intermediate aquifer system, and the Floridan aquifer system. The surficial aquifer system principally consists of unconsoli-dated to poorly indurated siliciclastic deposits. The intermediate aquifer system, which contains the intermediate confining unit, lies below the surficial aquifer system (where present), and generally consists of fine-grained, uncon-solidated deposits of quartz sand, silt, and clay with interbedded limestone of Miocene age. Regionally, the intermediate aquifer system and intermediate con-fining unit act as a confining unit that restricts the exchange of water between the over

  7. Flood-tracking chart for the Withlacoochee and Little River Basins in south-central Georgia and northern Florida

    Science.gov (United States)

    Gotvald, Anthony J.; McCallum, Brian E.; Painter, Jaime A.

    2014-01-01

    The U.S. Geological Survey (USGS), in cooperation with other Federal, State, and local agencies, operates a flood-monitoring system in the Withlacoochee and Little River Basins. This system is a network of automated river stage stations (ten are shown on page 2 of this publication) that transmit stage data through satellite telemetry to the USGS in Atlanta, Georgia and the National Weather Service (NWS) in Peachtree City, Georgia. During floods, the public and emergency response agencies use this information to make decisions about road closures, evacuations, and other public safety issues. This Withlacoochee and Little River Basins flood-tracking chart can be used by local citizens and emergency response personnel to record the latest river stage and predicted flood-crest information along the Withlacoochee River, Little River, and Okapilco Creek in south-central Georgia and northern Florida. By comparing the current stage (water-surface level above a datum) and predicted flood crest to the recorded peak stages of previous floods, emergency response personnel and residents can make informed decisions concerning the threat to life and property.

  8. Sources and chronology of nitrate contamination in spring waters, Suwannee River basin, Florida

    Science.gov (United States)

    Katz, Brian G.; Hornsby, H.D.; Bohlke, J.K.; Mokray, M.F.

    1999-01-01

    A multi-tracer approach, which consisted of analyzing water samples for n aturally occurring chemical and isotopic indicators, was used to better understand sources and chronology of nitrate contamination in spring wate rs discharging to the Suwannee and Santa Fe Rivers in northern Florida. Dur ing 1997 and 1998, as part of a cooperative study between the Suwannee River Water Management District and the U.S. Geological Survey, water samples were collected and analyzed from 24 springs and two wells for major ions, nutrients, dissolved organic carbon, and selected environmental isotopes [18O/16O, D/H, 13C/12C, 15N/14N]. To better understand when nitrate entered the ground-water system, water samples were analyzed for chlorofluorocarbons (CFCs; CCl3F, CCl2F2, and C2Cl3F3) and tritium (3H); in this way, the apparent ages and residence times of spring waters and water from shallow zones in the Upper Floridan aquifer were determined. In addition to information obtained from the use of isotopic and other chemical tracers, information on changes in land-use activities in the basin during 1954-97 were used to estimate nitrogen inputs from nonpoint sources for five counties in the basin. Changes in nitrate concentrations in spring waters with time were compared with estimated nitrogen inputs for Lafayette and Suwannee Counties. Agricultural activities [cropland farming, animal farming operations (beef and dairy cows, poultry, and swine)] along with atmospheric deposition have contributed large quantities of nitrogen to ground water in the Suwannee River Basin in northern Florida. Changes in agricultural land use during the past 40 years in Alachua, Columbia, Gilchrist, Lafayette, and Suwannee Counties have contributed variable amounts of nitrogen to the ground-water system. During 1955-97, total estimated nitrogen from all nonpoint sources (fertilizers, animal wastes, atmospheric deposition, and septic tanks) increased continuously in Gilchrist and Lafayette Counties. In

  9. 2009 St. Johns River Water Management District (SJRWMD) Lidar: Portions of Orange and Seminole Counties, Florida

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The project area covers 318 square miles in the eastern half of Seminole County plus portions of north central and northeast Orange County in the state of Florida....

  10. Applying downscaled Global Climate Model data to a groundwater model of the Suwannee River Basin, Florida, USA

    Science.gov (United States)

    Swain, Eric D.; Davis, J. Hal

    2016-01-01

    The application of Global Climate Model (GCM) output to a hydrologic model allows for comparisons between simulated recent and future conditions and provides insight into the dynamics of hydrology as it may be affected by climate change. A previously developed numerical model of the Suwannee River Basin, Florida, USA, was modified and calibrated to represent transient conditions. A simulation of recent conditions was developed for the 372-month period 1970-2000 and was compared with a simulation of future conditions for a similar-length period 2039-2069, which uses downscaled GCM data. The MODFLOW groundwater-simulation code was used in both of these simulations, and two different MODFLOW boundary condition “packages” (River and Streamflow-Routing Packages) were used to represent interactions between surface-water and groundwater features.

  11. Emendation and new species of Hapalorhynchus Stunkard, 1922 (Digenea: Schistosomatoidea) from musk turtles (Kinosternidae: Sternotherus) in Alabama and Florida rivers.

    Science.gov (United States)

    Roberts, Jackson R; Halanych, Kenneth M; Arias, Cova R; Folt, Brian; Goessling, Jeffrey M; Bullard, Stephen A

    2017-12-01

    Hapalorhynchus Stunkard, 1922 is emended based on morphological study of existing museum specimens (type and voucher specimens) and newly-collected specimens infecting musk turtles (Testudines: Kinosternidae: Sternotherus spp.) from rivers in Alabama and Florida (USA). Hapalorhynchus conecuhensis n. sp. is described from an innominate musk turtle, Sternotherus cf. minor, (type host) from Blue Spring (31°5'27.64″N, 86°30'53.21″W; Pensacola Bay Basin, Alabama) and the loggerhead musk turtle, Sternotherus minor (Agassiz, 1857) from the Wacissa River (30°20'24.73″N, 83°59'27.56″W; Apalachee Bay Basin, Florida). It differs from congeners by lacking a body constriction at level of the ventral sucker, paired anterior caeca, and a transverse ovary as well as by having a small ventral sucker, proportionally short posterior caeca, nearly equally-sized anterior and posterior testes, a small cirrus sac, and a uterus extending dorsal to the ovary and the anterior testis. Specimens of Hapalorhynchus reelfooti Byrd, 1939 infected loggerhead musk turtles, stripe-necked musk turtles (Sternotherus peltifer Smith and Glass, 1947), Eastern musk turtles (Sternotherus odoratus [Latreille in Sonnini and Latreille, 1801]), and S. cf. minor. Those of Hapalorhynchus cf. stunkardi infected S. minor and S. odoratus. Sternothorus minor, S. peltifer, and S. cf. minor plus S. minor and S. odoratus are new host records for H. reelfooti and H. cf. stunkardi, respectively. This is the first report of an infected musk turtle from the Coosa and Tallapoosa Rivers (Mobile-Tensaw River Basin), Pensacola Bay Basin, or Apalachee Bay Basin. Sequence analysis of the large subunit rDNA (28S) showed a strongly-supported clade for Hapalorhynchus. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. A comparison of the reproductive physiology of largemouth bass, Micropterus salmoides, collected from the Escambia and Blackwater Rivers in Florida.

    Science.gov (United States)

    Orlando, E F; Denslow, N D; Folmar, L C; Guillette, L J

    1999-03-01

    Largemouth bass (LMB), Micropterus salmoides, were taken from the Escambia River (contaminated site) and the Blackwater River (reference site) near Pensacola, Florida. The Escambia River collection occurred downstream of the effluent from two identified point sources of pollution. These point sources included a coal-fired electric power plant and a chemical company. Conversely, the Blackwater River's headwaters and most of its length flow within a state park. Although there is some development on the lower part of the Blackwater River, fish were collected in the more pristine upper regions. Fish were captured by electroshocking and were maintained in aerated coolers. Physical measurements were obtained, blood was taken, and liver and gonads were removed. LMB plasma was assayed for the concentration of 17ss-estradiol (E2) and testosterone using validated radioimmunoassays. The presence of vitellogenin was determined by gel electrophoresis (SDS-PAGE) and Western blotting using a monoclonal antibody validated for largemouth bass vitellogenin. No differences in plasma concentrations of E2 or testosterone were observed in females from the two sites. Similarly, males exhibited no difference in plasma E2. However, plasma testosterone was lower in the males from the contaminated site, as compared to the reference site. Vitellogenic males occurred only at the contaminated site. Additionally, liver mass was proportionately higher in males from the contaminated site, as compared to males from the reference site. These data suggest that reproductive steroid levels may have been altered by increased hepatic enzyme activity, and the presence of vitellogenic males indicates that an exogenous source of estrogen was present in the Escambia River.

  13. Satellite Derived Water Quality Observations Are Related to River Discharge and Nitrogen Loads in Pensacola Bay, Florida

    Directory of Open Access Journals (Sweden)

    John C. Lehrter

    2017-09-01

    Full Text Available Relationships between satellite-derived water quality variables and river discharges, concentrations and loads of nutrients, organic carbon, and sediments were investigated over a 9-year period (2003–2011 in Pensacola Bay, Florida, USA. These analyses were conducted to better understand which river forcing factors were the primary drivers of estuarine variability in several water quality variables. Remote sensing reflectance time-series data were retrieved from the MEdium Resolution Imaging Spectrometer (MERIS and used to calculate monthly and annual estuarine time-series of chlorophyll a (Chla, colored dissolved organic matter (CDOM, and total suspended sediments (TSS. Monthly MERIS Chla varied from 2.0 mg m−3 in the lower region of the bay to 17.2 mg m−3 in the upper bay. MERIS CDOM and TSS exhibited similar patterns with ranges of 0.51–2.67 (m−1 and 0.11–8.9 (g m−3. Variations in the MERIS-derived monthly and annual Chla, CDOM, and TSS time-series were significantly related to monthly and annual river discharge and loads of nitrogen, organic carbon, and suspended sediments from the Escambia and Yellow rivers. Multiple regression models based on river loads (independent variables and MERIS Chla, CDOM, or TSS (dependent variables explained significant fractions of the variability (up to 62% at monthly and annual scales. The most significant independent variables in the regressions were river nitrogen loads, which were associated with increased MERIS Chla, CDOM, and TSS concentrations, and river suspended sediment loads, which were associated with decreased concentrations. In contrast, MERIS water quality variations were not significantly related to river total phosphorus loads. The spatially synoptic, nine-year satellite record expanded upon the spatial extent of past field studies to reveal previously unseen system-wide responses to river discharge and loading variation. The results indicated that variations in Pensacola Bay Chla

  14. Development of a solid-phase extraction system modified for preconcentration of emerging contaminants in large sample volumes from rivers of the lagoon system in the city of Rio de Janeiro, Brazil.

    Science.gov (United States)

    Lopes, Vitor Sergio Almeida; Riente, Roselene Ribeiro; da Silva, Alexsandro Araújo; Torquilho, Delma Falcão; Carreira, Renato da Silva; Marques, Mônica Regina da Costa

    2016-09-15

    A single method modified for monitoring of emerging contaminants in river water was developed for large sample volumes. Water samples from rivers of the lagoon system in the city of Rio de Janeiro (Brazil) were analyzed by the SPE-HPLC-MS-TOF analytical method. Acetaminophen was detected in four rivers in the concentration range of 0.09μgL(-1) to 0.14μgL(-1). Salicylic acid was also found in the four rivers in the concentration range of 1.65μgL(-1) to 4.81μgL(-1). Bisphenol-A was detected in all rivers in the concentration range of 1.37μgL(-1) to 39.86μgL(-1). Diclofenac was found in only one river, with concentration of 0.22μgL(-1). The levels of emerging organic pollutants in the water samples of the Jacarepaguá hydrographical basin are significant. The compounds are not routinely monitored and present potential risks to environmental health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. INVESTIGATIONS INTO THE EFFECTS OF SEASON AND WATER QUALITY ON OYSTERS (CRASSOSTREA VIRGINICA) AND ASSOCIATED FISH ASSEMBLAGES IN THE CALOOSAHATCHEE RIVER ESTUARY, FLORIDA: IMPLICATIONS OF ALTERED FRESHWATER INFLOW

    Science.gov (United States)

    A suite of biological and ecological responses of a Valued Ecosystem Component species, Crassostrea virginica, was used to investigate ecosystem-wide health effects of watershed alterations in the Caloosahatchee River estuary, Florida. The influence of water quality and season on...

  16. Location and description of transects for ecological studies in floodplain forests of the lower Suwannee River, Florida

    Science.gov (United States)

    Lewis, L.J.; Light, H.M.; Darst, M.R.

    2001-01-01

    Twelve transects were established in floodplain forests along the lower Suwannee River, Florida, as the principal data collection sites for a comprehensive study conducted by the U.S. Geological Survey and the Suwannee River Water Management District from 1996 to 2001. Data collected along the 12 transects included hydrologic conditions, land-surface elevations, soils, and vegetation of floodplain forests in relation to river flow. Transect locations are marked in the field with permanent markers at approximately 30 meter intervals. Detailed descriptions of the 12 transects and their locations are provided so that they can be used for future ecological studies. Descriptions of the transects include contact information necessary for access to the property on which the transects are located, maps showing transect locations and routes from the nearest city or major road, small scale maps of each transect showing marker locations, latitude and longitude of each marker, compass bearings of each transect line and graphs showing land-surface elevations of the transect with marker locations.

  17. Assessment of the hydraulic connection between ground water and the Peace River, west-central Florida

    Science.gov (United States)

    Lewelling, B.R.; Tihansky, A.B.; Kindinger, J.L.

    1998-01-01

    The hydraulic connection between the Peace River and the underlying aquifers along the length of the Peace River from Bartow to Arcadia was assessed to evaluate flow exchanges between these hydrologic systems. Methods included an evaluation of hydrologic and geologic records and seismic-reflection profiles, seepage investigations, and thermal infrared imagery interpretation. Along the upper Peace River, a progressive long-term decline in streamflow has occurred since 1931 due to a lowering of the potentiometric surface of the Upper Floridan aquifer by as much as 60 feet because of intensive ground-water withdrawals for phosphate mining and agriculture. Another effect from lowering the potentiometric surface has been the cessation of flow at several springs located near and within the Peace River channel, including Kissengen Spring, that once averaged a flow of about 19 million gallons a day. The lowering of ground-water head resulted in flow reversals at locations where streamflow enters sinkholes along the streambed and floodplain. Hydrogeologic conditions along the Peace River vary from Bartow to Arcadia. Three distinctive hydrogeologic areas along the Peace River were delineated: (1) the upper Peace River near Bartow, where ground-water recharge occurs; (2) the middle Peace River near Bowling Green, where reversals of hydraulic gradients occur; and (3) the lower Peace River near Arcadia, where ground-water discharge occurs. Seismic-reflection data were used to identify geologic features that could serve as potential conduits for surface-water and ground-water exchange. Depending on the hydrologic regime, this exchange could be recharge of surface water into the aquifer system or discharge of ground water into the stream channel. Geologic features that would provide pathways for water movement were identified in the seismic record; they varied from buried irregular surfaces to large-scale subsidence flexures and vertical fractures or enlarged solution conduits

  18. Hydrology, vegetation, and soils of four north Florida River flood plains with an evaluation of state and federal wetland determinations

    Science.gov (United States)

    Light, H.M.; Darst, M.R.; MacLaughlin, M.T.; Sprecher, S.W.

    1993-01-01

    A study of hydrologic conditions, vegetation, and soils was made in wetland forests of four north Florida streams from 1987 to 1990. The study was conducted by the U.S. Geological Survey in cooperation with the Florida Department of Environmental Regulation to support State and Federal efforts to improve wetland delineation methodology in flood plains. Plant communities and soils were described and related to topographic position and long-term hydrologic conditions at 10 study plots located on 4 streams. Detailed appendixes give average duration, frequency, and depth of flooding; canopy, subcanopy, and ground-cover vegetation; and taxonomic classification, series, and profile descriptions of soils for each plot. Topographic relief, range in stage, and depth of flooding were greatest on the alluvial flood plain of the Ochlockonee River, the largest of the four streams. Soils were silty in the lower elevations of the flood plain, and tree communities were distinctly different in each topographic zone. The Aucilla River flood plain was dominated by levees and terraces with very few depressions or low backwater areas. Oaks dominated the canopy of both lower and upper terraces of the Aucilla flood plain. Telogia Creek is a blackwater stream that is a major tributary of the Ochlockonee River. Its low, wet flood plain was dominated by Wyssa ogeche (Ogeechee tupelo) trees, had soils with mucky horizons, and was inundated by frequent floods of very short duration. The St. Marks River, a spring-fed stream with high base flow, had the least topographic relief and lowest range in stage of the four streams. St. Marks soils had a higher clay content than the other streams, and limestone bedrock was relatively close to the surface. Wetland determinations of the study plots based on State and Federal regulatory criteria were evaluated. Most State and Federal wetland determinations are based primarily on vegetation and soil characteristics because hydrologic records are usually not

  19. Long-Term Trends in Abundance and Distribution of Manatees (Trichechus Manatus) in the Northern Banana River, Brevard County, Florida

    Science.gov (United States)

    Provancha, J. A.; Provancha, M. J.

    1988-01-01

    Four aerial survey projects were conducted between 1977 and 1986 to determine the abundance, density and distribution of West Indian manatees (Trichechus manatus), in the northern Banana River, Kennedy Space Center, Florida. Manatee density and distribution within selected portions of the 78.5 sq km study area were determined. Peak numbers of manatees occurred in spring of each year. The maximum counts increased from 56 in 1978 to 297 in 1986. Manatee abundance was lowest in the winter of each year. Mean density per flight increased from 0.52 manatees/sq km in 1977-78 to 2.73/sq km in 1984-86. This increase may reflect increases in the east coast population or shifts in the population distribution. Distributional changes were observed in the study area through time, with a lower percentage of manatees occurring in industrial areas and a correspondingly higher percentage of manatees in nonindustrial areas by 1985.

  20. Florida's salt-marsh management issues: 1991-98.

    Science.gov (United States)

    Carlson, D B; O'Bryan, P D; Rey, J R

    1999-06-01

    During the 1990s, Florida has continued to make important strides in managing salt marshes for both mosquito control and natural resource enhancement. The political mechanism for this progress continues to be interagency cooperation through the Florida Coordinating Council on Mosquito Control and its Subcommittee on Managed Marshes (SOMM). Continuing management experience and research has helped refine the most environmentally acceptable source reduction methods, which typically are Rotational Impoundment Management or Open Marsh Water Management. The development of regional marsh management plans for salt marshes within the Indian River Lagoon by the SOMM has helped direct the implementation of the best management practices for these marshes. Controversy occasionally occurs concerning what management technique is most appropriate for individual marshes. The most common disagreement is over the benefits of maintaining an impoundment in an "open" vs. "closed" condition, with the "closed" condition, allowing for summer mosquito control flooding or winter waterfowl management. New federal initiatives influencing salt-marsh management have included the Indian River Lagoon-National Estuary Program and the Pesticide Environmental Stewardship Program. A new Florida initiative is the Florida Department of Environmental Protection's Eco-system Management Program with continuing involvement by the Surface Water Improvement and Management program. A developing mitigation banking program has the potential to benefit marsh management but mosquito control interests may suffer if not handled properly. Larvicides remain as an important salt-marsh integrated pest management tool with the greatest acreage being treated with temephos, followed by Bacillus thuringiensis israelensis and methoprene. However, over the past 14 years, use of biorational larvicides has increased greatly.

  1. Analysis of Fluvial Bed Sediments Along the Apalachicola River, Florida through Field Reconnaissance Studies

    Science.gov (United States)

    Passeri, D.; Hagen, S. C.; Daranpob, A.; Smar, D. E.

    2011-12-01

    River competence is an important parameter in understanding sediment transport in fluvial systems. Competence is defined as the measure of a stream's ability to transport a certain maximum grain size of sediment. Studies have shown that bed sediment particle size in rivers and streams tends to vary spatially along the direction of stream flow. Over a river section several reaches long, variability of sediment particle sizes can be seen, often becoming finer downstream. This phenomenon is attributed to mechanisms such as local control of stream gradient, coarse tributary sediment supply or particle breakdown. Average particle size may also be smaller in tributary sections of rivers due to river morphology. The relationship between river mean velocity and particle size that can be transported has also been explored. The Hjulstrom curve classifies this relationship by relating particle size to velocity, dividing the regions of sedimentation, transportation, and erosion. The curve can also be used to find values such as the critical erosion velocity (the velocity required to transport particles of various sizes in suspension) and settling velocity (the velocity at which particles of a given size become too heavy to be transported and fall out of suspension, consequently causing deposition). The purpose of this research is to explore the principles of river competence through field reconnaissance collection and laboratory analysis of fluvial sediment core samples along the Apalachicola River, FL and its distributaries. Sediment core samples were collected in the wetlands and estuarine regions of the Apalachicola River. Sieve and hydrometer analyses were performed to determine the spatial distribution of particle sizes along the river. An existing high resolution hydrodynamic model of the study domain was used to simulate tides and generate river velocities. The Hjulstrom curve and the generated river velocities were used to define whether sediment was being transported

  2. Hydrologic Conditions that Influence Streamflow Losses in a Karst Region of the Upper Peace River, Polk County, Florida

    Science.gov (United States)

    Metz, P.A.; Lewelling, B.R.

    2009-01-01

    The upper Peace River from Bartow to Fort Meade, Florida, is described as a groundwater recharge area, reflecting a reversal from historical groundwater discharge patterns that existed prior to the 1950s. The upper Peace River channel and floodplain are characterized by extensive karst development, with numerous fractures, crevasses, and sinks that have been eroded in the near-surface and underlying carbonate bedrock. With the reversal in groundwater head gradients, river water is lost to the underlying groundwater system through these karst features. An investigation was conducted to evaluate the hydrologic conditions that influence streamflow losses in the karst region of the upper Peace River. The upper Peace River is located in a basin that has been altered substantially by phosphate mining and increases in groundwater use. These alterations have changed groundwater flow patterns and caused streamflow declines through time. Hydrologic factors that have had the greatest influence on streamflow declines in the upper Peace River include the lowering of the potentiometric surfaces of the intermediate aquifer system and Upper Floridan aquifer beneath the riverbed elevation due to below-average rainfall (droughts), increases in groundwater use, and the presence of numerous karst features in the low-water channel and floodplain that enhance the loss of streamflow. Seepage runs conducted along the upper Peace River, from Bartow to Fort Meade, indicate that the greatest streamflow losses occurred along an approximate 2-mile section of the river beginning about 1 mile south of the Peace River at Bartow gaging station. Along the low-water and floodplain channel of this 2-mile section, there are about 10 prominent karst features that influence streamflow losses. Losses from the individual karst features ranged from 0.22 to 16 cubic feet per second based on measurements made between 2002 and 2007. The largest measured flow loss for all the karst features was about 50 cubic

  3. River of Interests: Water Management in South Florida and the Everglades, 1948-2010

    Science.gov (United States)

    2011-07-01

    influencing hundreds of people to write letters to the secretary of the interior about the project. In this essay , entitled "Rape of the Oklawaha...as "the prospect of helter-skelter development around the airport.ඏ Look issued a photo essay depicting "the assault on the Everglades,ඐ while...the town of Kissimmee, meandered along a 92-mile course through central Florida, eventu- ally reaching Lake Okeechobee. A lyrical description of the

  4. A Preliminary Assessment of Sources of Nitrate in Springwaters, Suwannee River Basin, Florida

    National Research Council Canada - National Science Library

    Katz, Brian G; Hornsby, H. D

    1998-01-01

    ... contamination in the middle Suwannee River region. In July and August 1997, water samples were collected and analyzed from six springs and two wells for major ions, nutrients, and dissolved organic carbon...

  5. Potential effects of deepening the St. Johns River navigation channel on saltwater intrusion in the surficial aquifer system, Jacksonville, Florida

    Science.gov (United States)

    Bellino, Jason C.; Spechler, Rick M.

    2013-01-01

    The U.S. Army Corps of Engineers (USACE) has proposed dredging a 13-mile reach of the St. Johns River navigation channel in Jacksonville, Florida, deepening it to depths between 50 and 54 feet below North American Vertical Datum of 1988. The dredging operation will remove about 10 feet of sediments from the surficial aquifer system, including limestone in some locations. The limestone unit, which is in the lowermost part of the surficial aquifer system, supplies water to domestic wells in the Jacksonville area. Because of density-driven hydrodynamics of the St. Johns River, saline water from the Atlantic Ocean travels upstream as a saltwater “wedge” along the bottom of the channel, where the limestone is most likely to be exposed by the proposed dredging. A study was conducted to determine the potential effects of navigation channel deepening in the St. Johns River on salinity in the adjacent surficial aquifer system. Simulations were performed with each of four cross-sectional, variable-density groundwater-flow models, developed using SEAWAT, to simulate hypothetical changes in salinity in the surficial aquifer system as a result of dredging. The cross-sectional models were designed to incorporate a range of hydrogeologic conceptualizations to estimate the effect of uncertainty in hydrogeologic properties. The cross-sectional models developed in this study do not necessarily simulate actual projected conditions; instead, the models were used to examine the potential effects of deepening the navigation channel on saltwater intrusion in the surficial aquifer system under a range of plausible hypothetical conditions. Simulated results for modeled conditions indicate that dredging will have little to no effect on salinity variations in areas upstream of currently proposed dredging activities. Results also indicate little to no effect in any part of the surficial aquifer system along the cross section near River Mile 11 or in the water-table unit along the cross

  6. Agricultural irrigated land-use inventory for the counties in the Suwannee River Water Management District in Florida, 2015

    Science.gov (United States)

    Marella, Richard L.; Dixon, Joann F.; Berry, Darbi R.

    2016-07-28

    A detailed inventory of irrigated crop acreage is not available at the level of resolution needed to accurately estimate agricultural water use or to project future water demands in many Florida counties. A detailed digital map and summary of irrigated acreage during the 2015 growing season was developed for 13 of the 15 counties that compose the Suwannee River Water Management District. The irrigated areas were delineated using land-use data, orthoimagery, and information obtained from the water management district consumptive water-use permits that were then field verified between May and November of 2015. Selected attribute data were collected for the irrigated areas, including crop type, primary water source, and type of irrigation system. Results indicate that an estimated 113,134 acres were either irrigated or had potential for irrigation in all or part of the 13 counties within the Suwannee River Water Management District during 2015. This estimate includes 108,870 acres of field-verified, irrigated crops and 4,264 acres of irrigated land observed as (1) idle (with an irrigation system visible but no crop present at the time of the field-verification visit), (2) acres that could not be verified during field visits, or (3) acres that were located on publicly owned research lands.

  7. Atmospheric deposition of nutrients to north Florida rivers: A multivariate statistical analysis. Final report. Master's thesis

    International Nuclear Information System (INIS)

    Fu, J.

    1991-01-01

    Atmospheric nutrient input to the Apalachicola Bay estuary was studied because it has been demonstrated that atmospheric deposition can be a major source of nutrients to eastern U.S. estuaries. Besides the Apalachicola River, the Sopchoppy and the Ochlockonee were also selected for a comparative analysis. Receptor model, absolute principal of component analysis (APCA), and mass balance methods were applied in the study. The results of the study show that nitrogen is probably not a limiting nutrient in the three rivers because their N:P mole ratios are nearly 3 times higher than the Redfield ratio for photosynthesis. The total atmospheric nitrogen depositions in the three river watershed are at least as great as their river fluxes. In the Apalachicola River, the atmospheric source of nitrogen is found to be several times higher than the largest possible input of urban sewage. Atmospheric deposition, therefore, might be the dominant nitrogen source entering the estuary. The results of APCA show that Apalachicola River water is mainly a mixture of components that correspond in their compositions to aged rain, ground water, and fresh rain. Atmospheric nitrate deposition is the result of the air pollution, i.e., acid rain. The studies also show that the annual average deposition of nitrate has a narrow range, mainly from 5.8 to 11.5 kg/ha/yr in most of the NADP sites in the 8 southeastern states. Since all the software and data sets employed in the study are accessible nationwide, the methods could be applied in other watersheds

  8. Estimation of survival of adult Florida manatees in the Crystal River, at Blue Spring, and on the Atlantic Coast

    Science.gov (United States)

    O'Shea, Thomas J.; Langtimm, Catherine A.; O'Shea, Thomas J.; Ackerman, B.B.; Percival, H. Franklin

    1995-01-01

    We applied Cormack-Jolly-Seber open population models to manatee (Trichechus manatus latirostris) photo-identification databases to estimate adult survival probabilities. The computer programs JOLLY and RECAPCO were used to estimate survival of 677 individuals in three study areas: Crystal River (winters 1977-78 to 1990-91), Blue Spring (winters 1977-78 to 1990-91), and the Atlantic Coast (winters 1984-85 to 1990-91). We also estimated annual survival from observations of 111 manatees tagged for studies with radiotelemetry. Survival estimated from observations with telemetry had broader confidence intervals than survival estimated with the Cormack-Jolly-Seber models. Annual probabilities of capture based on photo-identification records were generally high. The mean annual adult survival estimated from sighting-resighting records was 0.959-0.962 in the Crystal River and 0.936-0.948 at Blue Spring and may be high enough to permit population growth, given the values of other life-history parameters. On the Atlantic Coast, the estimated annual adult survival (range of means = 0.877-0.885) may signify a declining population. However, for several reasons, interpretation of data from the latter study group should be tempered with caution. Adult survivorship seems to be constant with age in all three study groups. No strong differences were apparent between adult survival ofmales and females in the Crystal River or at Blue Spring; the basis of significant differences between sexes on the Atlantic Coast is unclear. Future research into estimating survival with photo-identification and the Cormack-Jolly-Seber models should be vigorously pursued. Estimates of annual survival can provide an additional indication of Florida manatee population status with a stronger statistical basis than aerial counts and carcass totals.

  9. Relation between ground water and surface water in the Hillsborough River basin, west-central Florida

    Science.gov (United States)

    Wolansky, R.M.; Thompson, T.H.

    1987-01-01

    The relation between groundwater and surface water in the Hillsborough River basin was defined through the use of: seismic-reflection profiling along selected reaches of the Hillsborough River, and evaluation of streamflow, rainfall, groundwater levels, water quality, and geologic data. Major municipal well fields in the basin are Morris Bridge and Cypress Creek where an averages of 15.3 and 30.0 million gal/day (mgd), respectively, were pumped in 1980. Mean annual rainfall for the study area is 53.7 inches. Average rainfall for 1980, determined from eight rainfall stations, was 49.7 inches. Evapotranspiration, corrected for the 5% of the basin that is standing water, was 35.7 in/year. The principal geohydrologic units in the basin are the surficial aquifer, the intermediate aquifer and confining beds, the Upper Floridan aquifer, the middle confining unit, and the Lower Floridan aquifer. Total pumpage of groundwater in 1980 was 98.18 mgd. The surficial aquifer and the intermediate aquifer are not used for major groundwater supply in the basin. Continuous marine seismic-reflection data collected along selected reaches of the Hillsborough River were interpreted to define the riverbed profile, the thickness of surficial deposits, and the top of persistent limestone. Major areas of groundwater discharge near the Hillsborough River and its tributaries are the wetlands adjacent to the river between the Zephyrhills gaging stations and Fletcher Avenue and the wetlands adjacent to Cypress Creek. An estimated 20 mgd seeps upward from the Upper Floridan aquifer within those wetland areas. The runoff/sq mi is greater at the Zephyrhills station than at Morris Bridge. However, results of groundwater flow models and potentiometric-surface maps indicate that groundwater is flowing upward along the Hillsborough River between the Zephyrhills gage and the Morris Bridge gage. This upward leakage is lost to evapotranspiration. An aquifer test conducted in 1978 at the Morris Bridge well

  10. Geomorphic origin of Merritt Island-Cape Canaveral, Florida, USA: A paleodelta of the reversed St. Johns River?

    Science.gov (United States)

    Adams, Peter N.

    2018-04-01

    The Merritt Island-Cape Canaveral (MICCSC) sedimentary complex consists of a series of adjacent, non-conformable, beach ridge sets that suggest a multi-phase constructional history, but the feature's geomorphic and sedimentary origins are not well-understood. In spite of its notable sedimentary volume (surface area = 1200 km2), the MICCSC lacks a clear sediment source, or supply mechanism, to explain its presence today. Previously published U/Th, radiocarbon and OSL dates indicate that beach ridge deposition was active during MIS 5 (130-80 ka) on Merritt Island, but has occurred over a shorter, younger time interval on Cape Canaveral proper (6 ka to present). In this paper, it is proposed that the MICCSC is an abandoned paleodelta whose fluvial source provided a sediment supply sufficient for coastal progradation. Although the MICCSC, today, does not receive an appreciable sediment supply, the nearly 23,000 km2 drainage basin of the St. Johns River may well have provided such a sediment supply during MIS 5 times. This low-gradient fluvial system currently empties to the Atlantic Ocean some 200 km north of the MICCSC (near Jacksonville, Florida) but may have flowed southward during the time of MICCSC sedimentary construction, then experienced flow reversal since MIS 5 times. Three possible uplift mechanisms are proposed to explain the northward down-tilting that may have reversed the flow direction of the St. Johns, abandoning deltaic construction of the MICCSC: (1) karst-driven, flexural isostatic uplift in response to carbonate rock dissolution in central Florida, (2) glacio-hydro-isostatic tilting/back-tilting cycles during loading and unloading of the Laurentide ice sheet during the Pleistocene, and (3) mantle convection-driven dynamic topography operating within southeastern North America since the Pliocene. This example testifies to the sensitivity of low-gradient, low-relief landscapes to various sources of uplift, be they isostatic or otherwise.

  11. Geohydrology of the Aucilla-Suwannee-Ochlockonee River Basin, south-central Georgia and adjacent parts of Florida

    Science.gov (United States)

    Torak, Lynn J.; Painter, Jaime A.; Peck, Michael F.

    2010-01-01

    Major streams and tributaries located in the Aucilla-Suwannee-Ochlockonee (ASO) River Basin of south-central Georgia and adjacent parts of Florida drain about 8,000 square miles of a layered sequence of clastic and carbonate sediments and carbonate Coastal Plain sediments consisting of the surficial aquifer system, upper semiconfining unit, Upper Floridan aquifer, and lower confining unit. Streams either flow directly on late-middle Eocene to Oligocene karst limestone or carve a dendritic drainage pattern into overlying Miocene to Holocene sand, silt, and clay, facilitating water exchange and hydraulic connection with geohydrologic units. Geologic structures operating in the ASO River Basin through time control sedimentation and influence geohydrology and water exchange between geohydrologic units and surface water. More than 300 feet (ft) of clastic sediments overlie the Upper Floridan aquifer in the Gulf Trough-Apalachicola Embayment, a broad area extending from the southwest to the northeast through the center of the basin. These clastic sediments limit hydraulic connection and water exchange between the Upper Floridan aquifer, the surficial aquifer system, and surface water. Accumulation of more than 350 ft of low-permeability sediments in the Southeast Georgia Embayment and Suwannee Strait hydraulically isolates the Upper Floridan aquifer from land-surface hydrologic processes in the Okefenokee Basin physiographic district. Burial of limestone beneath thick clastic overburden in these areas virtually eliminates karst processes, resulting in low aquifer hydraulic conductivity and storage coefficient despite an aquifer thickness of more than 900 ft. Conversely, uplift and faulting associated with regional tectonics and the northern extension of the Peninsular Arch caused thinning and erosion of clastic sediments overlying the Upper Floridan aquifer southeast of the Gulf Trough-Apalachicola Embayment near the Florida-Georgia State line. Limestone dissolution in

  12. A preliminary assessment of sources of nitrate in springwaters, Suwannee River basin, Florida

    Science.gov (United States)

    Katz, B.G.; Hornsby, H.D.

    1998-01-01

    A cooperative study between the Suwannee River Water Management District (SRWMD) and the U.S. Geological Survey (USGS) is evaluating sources of nitrate in water from selected springs and zones in the Upper Floridan aquifer in the Suwannee River Basin. A multi-tracer approach, which consists of the analysis of water samples for naturally occurring chemical and isotopic indicators, is being used to better understand sources and chronology of nitrate contamination in the middle Suwannee River region. In July and August 1997, water samples were collected and analyzed from six springs and two wells for major ions, nutrients, and dissolved organic carbon. These water samples also were analyzed for environmental isotopes [18O/16O, D/H, 13C/12C, 15N/14N] to determine sources of water and nitrate. Chlorofluorocarbons (CCl3F, CCl2F2, and C2Cl3F3) and tritium (3H) were analyzed to assess the apparent ages (residence time) of springwaters and water from the Upper Floridan aquifer. Delta 15N-NO3 values in water from the six springs range from 3.94 per mil (Little River Springs) to 8.39 per mil (Lafayette Blue Spring). The range of values indicates that nitrate in the sampled springwaters most likely originates from a mixture of inorganic (fertilizers) and organic (animal wastes) sources, although the higher delta 15N-NO3 value for Lafayette Blue Spring indicates that an organic source of nitrogen is likely at this site. Water samples from the two wells sampled in Lafayette County have high delta 15N-NO3 values of 10.98 and 12.1 per mil, indicating the likelihood of an organic source of nitrate. These two wells are located near dairy and poultry farms, where leachate from animal wastes may contribute nitrate to ground water. Based on analysis of chlorofluorocarbons in ground water, the mean residence time of water in springs ranges from about 12 to 25 years. Chlorofluorocarbons-modeled recharge dates for water samples from the two shallow zones in the Upper Floridan aquifer

  13. Whole Genome Sequence Analysis of an Alachlor and Endosulfan Degrading Micrococcus sp. strain 2385 Isolated from Ochlockonee River, Florida.

    Science.gov (United States)

    Pathak, Ashish; Chauhan, Ashvini; Ewida, Ayman Y I; Stothard, Paul

    2016-01-01

    We recently isolated Micrococcus sp. strain 2385 from Ochlockonee River, Florida and demonstrated potent biodegradative activity against two commonly used pesticides- alachlor [(2-chloro-2`,6`-diethylphenyl-N (methoxymethyl)acetanilide)] and endosulfan [(6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9methano-2,3,4-benzo(e)di-oxathiepin-3-oxide], respectively. To further identify the repertoire of metabolic functions possessed by strain 2385, a draft genome sequence was obtained, assembled, annotated and analyzed. The genome sequence of Micrococcus sp. strain 2385 consisted of 1,460,461,440 bases which assembled into 175 contigs with an N50 contig length of 50,109 bases and a coverage of 600x. The genome size of this strain was estimated at 2,431,226 base pairs with a G+C content of 72.8 and a total number of 2,268 putative genes. RAST annotated a total of 340 subsystems in the genome of strain 2385 along with the presence of 2,177 coding sequences. A genome wide survey indicated that that strain 2385 harbors a plethora of genes to degrade other pollutants including caprolactam, PAHs (such as naphthalene), styrene, toluene and several chloroaromatic compounds.

  14. Evaluation of Water Quality for Two St. Johns River Tributaries Receiving Septic Tank Effluent, Duval County, Florida

    Science.gov (United States)

    Wicklein, Shaun M.

    2004-01-01

    Tributary streamflow to the St. Johns River in Duval County is thought to be affected by septic tank leachate from residential areas adjacent to these tributaries. Water managers and the city of Jacksonville have committed to infrastructure improvements as part of a management plan to address the impairment of tributary water quality. In order to provide data to evaluate the effects of future remedial activities in selected tributaries, major ion and nutrient concentrations, fecal coliform concentrations, detection of wastewater compounds, and tracking of bacterial sources were used to document septic tank influences on the water quality of selected tributaries. The tributaries Fishing Creek and South Big Fishweir Creek were selected because they drain subdivisions identified as high priority locations for septic tank phase-out projects: the Pernecia and Murray Hill B subdivisions, respectively. Population, housing (number of residences), and septic tank densities for the Murray Hill B subdivision are greater than those for the Pernecia subdivision. Water-quality samples collected in the study basins indicate influences from ground water and septic tanks. Estimated concentrations of total nitrogen ranged from 0.33 to 2.86 milligrams per liter (mg/L), and ranged from less than laboratory reporting limit (0.02 mg/L) to 0.64 mg/L for total phosphorus. Major ion concentrations met the State of Florida Class III surface-water standards; total nitrogen and total phosphorus concentrations exceeded the U.S. Environmental Protection Agency Ecoregion XII nutrient criteria for rivers and streams 49 and 96 percent of the time, respectively. Organic wastewater compounds detected at study sites were categorized as detergents, antioxidants and flame retardants, manufactured polycarbonate resins, industrial solvents, and mosquito repellent. The most commonly detected compound was para-nonylphenol, a breakdown product of detergent. Results of wastewater sampling give evidence that

  15. Organic and inorganic carbon dynamics in a karst aquifer: Santa Fe River Sink-Rise system, north Florida, USA

    Science.gov (United States)

    Jin, Jin; Zimmerman, Andrew R.; Moore, Paul J.; Martin, Jonathan B.

    2014-03-01

    Spatiotemporal variations in dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), major ions concentrations and other geochemical parameters including stable carbon isotopes of DIC (δ13CDIC), were measured in surface water and deep and shallow well water samples of the Santa Fe River Sink-Rise eogenetic karst system, north Florida, USA. Three end-member water sources were identified: one DOC-rich/DIC-poor/δ13CDIC-depleted, one DOC-poor/DIC-rich/δ13CDIC-enriched, and one enriched in major ions. Given their spatiotemporal distributions, they were presumed to represent soil water, upper aquifer groundwater, and deep aquifer water sources, respectively. Using assumed ratios of Na+, Cl, and SO42- for each end-member, a mixing model calculated the contribution of each water source to each sample. Then, chemical effects of biogeochemical reactions were calculated as the difference between those predicted by the mixing model and measured species concentrations. In general, carbonate mineral dissolution occurred throughout the Sink-Rise system, surface waters were net autotrophic and the subsurface was in metabolic balance, i.e., no net DOC or DIC production or consumption. However, there was evidence for chemolithoautotrophy, perhaps by hydrogen oxidizing microbes, at some deep aquifer sites. Mineralization of this autochthonous natural dissolved organic matter (NDOM) led to localized carbonate dissolution as did surface water-derived NDOM supplied to shallow well sites during the highest flow periods. This study demonstrates linkages between hydrology, abiotic and microbial processes and carbon dynamics and has important implications for groundwater quality, karst morphologic evolution, and hydrogeologic projects such as aquifer storage and recovery in karst systems.

  16. DV142 The application of the LOICZ-model on the Sacco di Goro Lagoon, Italy

    NARCIS (Netherlands)

    Edel, I.M.A.

    2002-01-01

    This report examines the application of the LOICZ-model to the Sacca di Goro lagoon. This estuary is located in the Po river delta, along de North Adriatic Coast, in Northern Italy. Activities in the lagoon itself, like fishery, aquaculture, tourism and activities in the hinterland, like:

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

    Science.gov (United States)

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

    2017-10-01

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

  18. A Blue Lagoon Function

    DEFF Research Database (Denmark)

    Markvorsen, Steen

    2007-01-01

    We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$.......We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$....

  19. Dynamics of marsh-mangrove ecotone since the mid-Holocene: A palynological study of mangrove encroachment and sea level rise in the Shark River Estuary, Florida.

    Science.gov (United States)

    Yao, Qiang; Liu, Kam-Biu

    2017-01-01

    Sea level rise and the associated inland shift of the marsh-mangrove ecotone in south Florida have raised many scientific and management concerns in recent years. Holocene paleoecological records can provide an important baseline to shed light on the long-term dynamics of vegetation changes across this ecotone in the past, which is needed to predict the future. In this study, we present palynological, X-ray fluorescence, and loss-on ignition data from four sedimentary cores recovered from a 20-km marine-to-freshwater transect along the Shark River Estuary, southwest Everglades, to document the patterns and processes of coastal vegetation changes in response to sea level rise since the mid-Holocene. Our record indicates that freshwater marsh progressively replaced marl prairies at the Shark River Estuary between 5700 and 4400 cal yr BP. As marine transgression continued, marine influence reached the threshold necessary for mangroves to establish at the current mouth of the Shark River Slough at 3800 cal yr BP. During the next 3000 years, although sea level rise in the Western North Atlantic slowed down to 0.4 mm/yr, a spatial and temporal gradient was evident as the marsh-mangrove ecotone shifted inland by 20 km from 3800 to 800 cal yr BP, accompanied by a gradual landward replacement of freshwater marsh by mangrove forest. If sea level continues to rise at 2.33 mm/yr in the 21st century in south Florida, it is possible that marine influence will reach the threshold for mangroves to establish in the central Everglades, and we could expect a much more aggressive mangrove encroachment toward the northern and interior parts of south Florida in the next few centuries.

  20. A Century of changes for Razelm-Sinoe Lagoon System

    Science.gov (United States)

    Scrieciu, Marian-Albert; Stanica, Adrian

    2014-05-01

    A Century of changes for Razelm-Sinoe Lagoon System Marian-Albert Scrieciu (a), Adrian Stanica (a) (a) National Institute of Marine Geology and Geoecology e GeoEcoMar, Str. Dimitrie Onciul 23e25, Sector 2, 024053 Bucharest, Romania Razelm-Sinoe Lagoon System, situated in the NW part of the Black Sea, in tight connection with the Danube Delta, has been subject to major changes due to human interventions in the past century. These changes have resulted into a complete change of the Lagoon specific ecosystems compared to its pristine state. In its natural state, as brackish - transitional environment, Antipa (1894) mentions Razelm Lagoon as one of the places with the greatest fisheries around the Black Sea coast (about 1879 - 1884, there were approximately 10,000 fishermen, all working on the Razelm Sinoe Lagoon System). Starting with the end of the XIXth Century, new canals were dug and existing channels were dredged in order to develop tighter connections with the Danube River. The natural inlet of Portita was blocked four decades ago and connections between the various parts of the lagoon system were controlled by the building of locks and sluices. The 2 inlets of Sinoe Lagoon were also controlled during early 1980s. Under these conditions, the lagoon ecosystem changed from brackish towards freshwater, with major effects on the existing flora and fauna. The period of brutal interventions ended in 1989 and the Razelm-Sinoe Lagoon System became part of the Danube Delta Biosphere Reserve in 1991, with a strict policy of nature protection and restoration. Spatial planning has been the major management option for the entire reserve, lagoon system included. Plans for sustainable development of the Razelm-Sinoe Lagoon System have been built in a participative manner, involving the local stakeholders, as part of FP7 ARCH project. Special attention has been given to impacts of climate change. The study presents the vision for the development Razelm-Sinoe Lagoon System over

  1. Caracterização trófica da ictiofauna de três lagoas da planície aluvial do alto rio Paraná, Brasil Trophic characterization of ichthyofauna from three lagoons of the Upper Paraná river floodplain, Brazil

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Gomes

    2001-05-01

    Full Text Available Com o objetivo de avaliar a composição da ictiocenose de lagoas da planície aluvial do alto rio Paraná em relação às categorias tróficas, foram realizadas coletas nas lagoas Figueira, Genipapo e Pousada, em março/1999. Após as capturas e obtenção dos dados biométricos, os peixes foram eviscerados e os estômagos fixados em formol 4%. Os conteúdos estomacais foram analisados pelos métodos de freqüência de ocorrência e volumétrico combinados no Índice Alimentar (IAi. Foram amostradas 40 espécies, as quais foram agrupadas em 10 categorias tróficas, ou seja, detritívora, iliófaga, zooplanctófaga, algívora, carcinófaga, piscívora, insetívora, bentófaga, herbívora e onívora. Para a lagoa Pousada, foram importantes, em número, as categorias zooplanctófagas (48,31%, na lagoa Genipapo foram os iliófagos (74,96%, enquanto que para a lagoa Figueira algívoros sobressaíram, com 75,58% da captura, s. Em relação à biomassa, observou-se que detritívoros foram dominantes na lagoa Pousada (45,7% e lagoa Figueira (27,7%, enquanto que na lagoa Genipapo predominaram os iliófagos (90,0%. Registrou-se alta disponibilidade de camarões nas três lagoas, embora estes tenham sobressaído apenas na dieta dos peixes da lagoa Figueira (20,7%. Embora a maior distância entre as três lagoas seja inferior a 1km, elas são submetidas a diferentes níveis de influência do rio Paraná, e apresentam fisiografias distintas e composições ictiofaunísticas diversas. Além disso, várias espécies icticas apresentam dietas distintas conforme a lagoa considerada, revelando papeis distintos na cadeia trófica desses ambientesIchthyofauna from three lagoons of the upper Paraná River floodplain was evaluated according to trophic categories. Samples were obtained in the Figueira, Genipapo, and Pousada lagoons in March 1999. Stomach contents were analyzed according to methods of occurrence and volumetric frequency, combined in an alimentary

  2. Movements and habitat use locations of manatees within Kings Bay Florida during the Crystal River National Wildlife Refuge winter season (November 15–March 31)

    Science.gov (United States)

    Slone, Daniel H.; Butler, Susan M.; Reid, James P.

    2018-04-06

    Kings Bay, Florida, is one of the most important natural winter habitat locations for the federally threatened Trichechus manatus latirostris (Florida manatee). Crystal River National Wildlife Refuge was established in 1983 specifically to provide protection for manatees and their critical habitat. To aid managers at the refuge and other agencies with this task, spatial analyses of local habitat use locations and travel corridors of manatees in Kings Bay during manatee season (November 15–March 31) are presented based on Global Positioning System telemetry of 41 manatees over a 12-year timespan (2006−18). Local habitat use areas and travel corridors differed spatially when Gulf of Mexico water temperatures were cold (less than or equal to 17 degrees Celsius) versus when they were warm (greater than 17 degrees Celsius). During times of cold water, manatees were found in higher concentrations in the main springs and canals throughout the eastern side of the bay, whereas when waters were warm, they were found more generally throughout the bay and into Crystal River, except for the central open part of the bay and the southwest corner.

  3. The impact of river water intrusion on trace metal cycling in karst aquifers: an example from the Floridan aquifer system at Madison Blue Spring, Florida

    Science.gov (United States)

    Brown, A. L.; Martin, J. B.; Screaton, E.; Spellman, P.; Gulley, J.

    2011-12-01

    Springs located adjacent to rivers can serve as recharge points for aquifers when allogenic runoff increases river stage above the hydraulic head of the spring, forcing river water into the spring vent. Depending on relative compositions of the recharged water and groundwater, the recharged river water could be a source of dissolved trace metals to the aquifer, could mobilize solid phases such as metal oxide coatings, or both. Whether metals are mobilized or precipitated should depend on changes in redox and pH conditions as dissolved oxygen and organic carbon react following intrusion of the river water. To assess how river intrusion events affect metal cycling in springs, we monitored a small recharge event in April 2011 into Madison Blue Spring, which discharges to the Withlacoochee River in north-central Florida. Madison Blue Spring is the entrance to a phreatic cave system that includes over 7.8 km of surveyed conduits. During the event, river stage increased over base flow conditions for approximately 25 days by a maximum of 8%. Intrusion of the river water was monitored with conductivity, temperature and depth sensors that were installed within the cave system and adjacent wells. Decreased specific conductivity within the cave system occurred for approximately 20 days, reflecting the length of time that river water was present in the cave system. During this time, grab samples were collected seven times over a period of 34 days for measurements of major ion and trace metal concentrations at the spring vent and at Martz sink, a karst window connected to the conduit system approximately 150 meters from the spring vent. Relative fractions of surface water and groundwater were estimated based on Cl concentrations of the samples, assuming conservative two end-member mixing during the event. This mixing model indicates that maximum river water contribution to the groundwater system was approximately 20%. River water had concentrations of iron, manganese, and other

  4. Application of Acoustic and Optic Methods for Estimating Suspended-Solids Concentrations in the St. Lucie River Estuary, Florida

    Science.gov (United States)

    Patino, Eduardo; Byrne, Michael J.

    2004-01-01

    Acoustic and optic methods were applied to estimate suspended-solids concentrations in the St. Lucie River Estuary, southeastern Florida. Acoustic Doppler velocity meters were installed at the North Fork, Speedy Point, and Steele Point sites within the estuary. These sites provide varying flow, salinity, water-quality, and channel cross-sectional characteristics. The monitoring site at Steele Point was not used in the analyses because repeated instrument relocations (due to bridge construction) prevented a sufficient number of samples from being collected at the various locations. Acoustic and optic instruments were installed to collect water velocity, acoustic backscatter strength (ABS), and turbidity data that were used to assess the feasibility of estimating suspended-solids concentrations in the estuary. Other data collected at the monitoring sites include tidal stage, salinity, temperature, and periodic discharge measurements. Regression analyses were used to determine the relations of suspended-solids concentration to ABS and suspended-solids concentration to turbidity at the North Fork and Speedy Point sites. For samples used in regression analyses, measured suspended-solids concentrations at the North Fork and Speedy Point sites ranged from 3 to 37 milligrams per liter, and organic content ranged from 50 to 83 percent. Corresponding salinity for these samples ranged from 0.12 to 22.7 parts per thousand, and corresponding temperature ranged from 19.4 to 31.8 ?C. Relations determined using this technique are site specific and only describe suspended-solids concentrations at locations where data were collected. The suspended-solids concentration to ABS relation resulted in correlation coefficients of 0.78 and 0.63 at the North Fork and Speedy Point sites, respectively. The suspended-solids concentration to turbidity relation resulted in correlation coefficients of 0.73 and 0.89 at the North Fork and Speedy Point sites, respectively. The adequacy of the

  5. Salinity levels as a factor of phyto planktonic structure and diversity remediation in a lagoon impact by human activities. (Bolmon Lagoon, Mediterranean Coast, France)

    International Nuclear Information System (INIS)

    Fayolle, S.; Charpy-Roubaud, C.; Ollivier, A.; Maasri, A.; Franquet, E.

    2009-01-01

    The Bolmon lagoon (south-eastern France) is located in the coastal hinterland of the Mediterranean Sea. It is connected to the salty Berre pond and in the other hand receives fresh waters from the La Cadiere River. This hyper-shallow lagoon has been classified in the early 70's as β mixo-mesohaline. Bolmon lagoon is important for human activities (tourism, fishing) and for the preservation of the diversity of marine and birds species. In the last decades, the intensive urbanisation of its drainage basin induced a high eutrophication of its waters and, as a consequence, drastic modifications in the biodiversity and in the functioning os this ecosystem. (Author)

  6. Sediment dynamics in the restored reach of the Kissimmee River Basin, Florida: A vast subtropical riparian wetland

    Science.gov (United States)

    Schenk, E.R.; Hupp, C.R.; Gellis, A.

    2012-01-01

    Historically, the Kissimmee River Basin consisted of a broad nearly annually inundated riparian wetland similar in character to tropical Southern Hemisphere large rivers. The river was channelized in the 1960s and 1970s, draining the wetland. The river is currently being restored with over 10 000 hectares of wetlands being reconnected to 70 river km of naturalized channel. We monitored riparian wetland sediment dynamics between 2007 and 2010 at 87 sites in the restored reach and 14 sites in an unrestored reference reach. Discharge and sediment transport were measured at the downstream end of the restored reach. There were three flooding events during the study, two as annual flood events and a third as a greater than a 5-year flood event. Restoration has returned periodic flood flow to the riparian wetland and provides a mean sedimentation rate of 11.3 mm per year over the study period in the restored reach compared with 1.7 mm per year in an unrestored channelized reach. Sedimentation from the two annual floods was within the normal range for alluvial Coastal Plain rivers. Sediment deposits consisted of over 20% organics, similar to eastern blackwater rivers. The Kissimmee River is unique in North America for its hybrid alluvial/blackwater nature. Fluvial suspended-sediment measurements for the three flood events indicate that a majority of the sediment (70%) was sand, which is important for natural levee construction. Of the total suspended sediment load for the three flood events, 3%–16% was organic and important in floodplain deposition. Sediment yield is similar to low-gradient rivers draining to the Chesapeake Bay and alluvial rivers of the southeastern USA. Continued monitoring should determine whether observed sediment transport and floodplain deposition rates are normal for this river and determine the relationship between historic vegetation community restoration, hydroperiod restoration, and sedimentation.

  7. Biomedical health assessments of the Florida manatee in Crystal River - providing opportunities for training during the capture, handling, and processing of this endangered aquatic mammal

    Science.gov (United States)

    Bonde, Robert K.; Garrett, Andrew; Belanger, Michael; Askin, Nesime; Tan, Luke; Wittnich, Carin

    2012-01-01

    Federal and state researchers have been involved in manatee (Trichechus manatus) biomedical health assessment programs for a couple of decades. These benchmark studies have provided a foundation for the development of consistent capture, handling, and processing techniques and protocols. Biologists have implemented training and encouraged multi-agency participation whenever possible to ensure reliable data acquisition, recording, sample collection, publication integrity, and meeting rigorous archival standards. Under a U.S. Fish and Wildlife Service wildlife research permit granted to the U.S. Geological Survey (USGS) Sirenia Project, federal biologists and collaborators are allowed to conduct research studies on wild and captive manatees detailing various aspects of their biology. Therefore, researchers with the project have been collaborating on numerous studies over the last several years. One extensive study, initiated in 2006 has focused on health and fitness of the winter manatee population located in Crystal River, Florida. During those health assessments, capture, handling, and work-up training has been afforded to many of the participants. That study has successfully captured and handled 123 manatees. The data gathered have provided baseline information on manatee health, reproductive status, and nutritional condition. This research initiative addresses concerns and priorities outlined in the Florida Manatee Recovery Plan. The assessment teams strive to continue this collaborative effort to help advance our understanding of health-related issues confronting manatees throughout their range and interlacing these findings with surrogate species concepts.

  8. Reconnaissance of chemical and physical characteristics of selected bottom sediments of the Caloosahatchee River and estuary, tributaries, and contiguous bays, Lee County, Florida, July 20-30, 1998

    Science.gov (United States)

    Fernandez, Mario; Marot, M.E.; Holmes, C.W.

    1999-01-01

    This report summarizes a reconnaissance study, conducted July 20-30, 1998, of chemical and physical characteristics of recently deposited bottom sediments in the Caloosahatchee River and Estuary. Recently deposited sediments were identified using an isotopic chronometer, Beryllium-7 (7Be), a short-lived radioisotope. Fifty-nine sites were sampled in an area that encompasses the Caloosahatchee River (River) about three miles upstream from the Franklin Lock (S-79), the entire tidally affected length of the river (estuary), and the contiguous water bodies of Matlacha Pass, San Carlos Bay, Estero Bay, Tarpon Bay, and Pine Island Sound in Lee County, Florida. Bottom sediments were sampled for 7Be at 59 sites. From the results of the 7Be analysis, 30 sites were selected for physical and chemical analysis. Sediments were analyzed for particle size, total organic carbon (TOC), trace elements, and toxic organic compounds, using semiquantitative methods for trace elements and organic compounds. The semiquantitative scans of trace elements indicated that cadmium, copper, lead, and zinc concentrations, when normalized to aluminum, were above the natural background range at 24 of 30 sites. Particle size and TOC were used to characterize sediment deposition patterns and organic content. Pesticides, polychlorinated biphenyls (PCBs), and carcinogenic polycyclic aromatic hydrocarbons (CaPAHs) were determined at 30 sites using immunoassay analysis. The semiquantitative immunoassay analyses of toxic organic compounds indicated that all of the samples contained DDT, cyclodienes as chlordane (pesticides), and CaPAHs. PCBs were not detected. Based on analyses of the 30 sites, sediments at 10 of these sites were analyzed for selected trace elements and toxic organic compounds, including pesticides, PCBs, and PAHs, using quantitative laboratory procedures. No arsenic or cadmium was detected. Zinc was detected at two sites with concentrations greater than the lower limit of the range of

  9. Functional implications of changes in seagrass species composition in two shallow coastal lagoons

    Science.gov (United States)

    While the consequences of losing seagrass meadows are well known, there is less information on the functional implications of changes in seagrass species composition. In this study, we use data from a long-term monitoring project in shallow lagoons on the Florida Gulf Coast to as...

  10. Flow Velocity Water Temperature, and Conductivity in Shark River Slough, Everglades National Park, Florida: August 2001-June 2002

    National Research Council Canada - National Science Library

    Riscassi, Ami L; Schaffranek, Raymond W

    2003-01-01

    ...." Data collected at four locations in Shark River Slough, Everglades National Park during the 2001 -2002 wet season are documented in the report and methods used to process the data are described...

  11. Conservation: saving Florida's manatees

    Science.gov (United States)

    Bonde, Robert K.

    2008-01-01

    Robert K. Bonde of the U.S. Geological Survey writes about the protected population of manatees in Crystal River, Florida, including information about the threats they face as they migrate in and out of protected waters. Photographer Carol Grant shares images of "Angel," a newborn manatee she photographed early one winter morning.

  12. Impact assessment of the introduction of Cichla kelberi in a large Neotropical reservoir and its lateral lagoons (Upper Paraná River Basin, Brazil

    Directory of Open Access Journals (Sweden)

    M. Ferrareze

    Full Text Available Abstract This study aimed to understand how the introduction of Cichla kelberi in Rosana Reservoir (Paranapanema River affected the native ichthyofauna. Data on the structure of the small fish fauna assemblage were obtained before and after the introduction of this carnivorous species. Samplings were carried out in February and September of 2004, previously to the register of Cichla kelberi in the reservoir, and after its introduction, November of 2004, January, March, May and August of 2005, February and June of 2006, February and July of 2007, February and October of 2008 and February of 2009. A total of 4,693 fish, belonging to 43 different species was sampled between 2004 and 2009. The order Characiformes was the most abundant, followed by Perciformes and Siluriformes. Comparative analyses, before and after the introduction, could not demonstrate significant changes in composition, richness, abundance, biomass, mean length and diversity of fish. Aquatic insects were the main feeding item of C. kelberi, followed by tetragonopterinae fish. Cannibalism was recorded during the whole study period. The results showed that Cichla cannot deeply affect the ichthyofauna assemblages of a large Neotropical reservoir, at least in a short or medium term period after its introduction. The results also allowed concluding that the introduction of C. kelberi in the reservoir is in the phase 3. In this phase, the specie can survive and reproduce in the new environment; however it is not totally established and disseminated. The reasons for the fact that Cichla is still not dominant in Rosana Reservoir could be related to feeding competition, high rate of cannibalism and the presence of large amount of aquatic macrophytes (refuge zones. In spite of the results, the continuous monitoring of the role of non-native species on the local fish fauna is absolutely necessary because the impacts caused by colonization of this undesirable species can be magnified by

  13. Hydrology, Water Quality, and Surface- and Ground-Water Interactions in the Upper Hillsborough River Watershed, West-Central Florida

    Science.gov (United States)

    Trommer, J.T.; Sacks, L.A.; Kuniansky, E.L.

    2007-01-01

    A study of the Hillsborough River watershed was conducted between October 1999 through September 2003 to characterize the hydrology, water quality, and interaction between the surface and ground water in the highly karstic uppermost part of the watershed. Information such as locations of ground-water recharge and discharge, depth of the flow system interacting with the stream, and water quality in the watershed can aid in prudent water-management decisions. The upper Hillsborough River watershed covers a 220-square-mile area upstream from Hillsborough River State Park where the watershed is relatively undeveloped. The watershed contains a second order magnitude spring, many karst features, poorly drained swamps, marshes, upland flatwoods, and ridge areas. The upper Hillsborough River watershed is subdivided into two major subbasins, namely, the upper Hillsborough River subbasin, and the Blackwater Creek subbasin. The Blackwater Creek subbasin includes the Itchepackesassa Creek subbasin, which in turn includes the East Canal subbasin. The upper Hillsborough River watershed is underlain by thick sequences of carbonate rock that are covered by thin surficial deposits of unconsolidated sand and sandy clay. The clay layer is breached in many places because of the karst nature of the underlying limestone, and the highly variable degree of confinement between the Upper Floridan and surficial aquifers throughout the watershed. Potentiometric-surface maps indicate good hydraulic connection between the Upper Floridan aquifer and the Hillsborough River, and a poorer connection with Blackwater and Itchepackesassa Creeks. Similar water level elevations and fluctuations in the Upper Floridan and surficial aquifers at paired wells also indicate good hydraulic connection. Calcium was the dominant ion in ground water from all wells sampled in the watershed. Nitrate concentrations were near or below the detection limit in all except two wells that may have been affected by

  14. A Centennial Tribute, 1906-2006: History of U.S. Geological Survey Streamgaging Activities for the Suwannee River at White Springs, Florida

    Science.gov (United States)

    Verdi, Richard Jay; Tomlinson, Stewart A.

    2009-01-01

    For centuries, the banks of the Suwannee River at White Springs were considered a sacred ground where people sought refuge in its 'healing waters'. Many believed that the mineral-enriched waters cured illnesses. The U.S. Geological Survey began continuous streamgaging activities at White Springs, Florida, in 1906 after an increase in congressional appropriations and rapid town development due to growing tourism and residential population. In 1906, streamgage data was a once-per-day gage reading that were handwritten in a water-level booklet by a local observer with discharge measurements taken every 6 to 8 weeks by a hydrographer. In 2006, real-time data were recorded at 1-hour increments and transmitted to U.S. Geological Survey computer networks using the Geostationary Operational Environmental Satellite, thus enabling the general public to access readings within minutes of the actual measurement. Additional data and measurements are taken and made available for high or low flows that occur during significant floods and droughts. The gage at White Springs has recorded several historic hydrologic events that affected the Suwannee River and surrounding areas. Major droughts include those during 1931-35, 1949-57, and 1998-2002. Severe floods occurred in 1948, 1973, and 2004. On April 10, 1973, the discharge was 38,100 cubic feet per second, which is the highest recorded discharge for the period of record. A flood of this magnitude is expected at a recurrence interval of about once every 200 to 500 years.

  15. An evaluation of biomarkers of reproductive function and potential contaminant effects in Florida largemouth bass ( Micropterus salmoidesfloridanus) sampled from the St. Johns River.

    Science.gov (United States)

    Sepúlveda, María S; Johnson, William E; Higman, John C; Denslow, Nancy D; Schoeb, Trenton R; Gross, Timothy S

    2002-04-22

    The objective of this study was to describe and compare several reproductive parameters for Florida largemouth bass (Micropterus salmoides floridanus) inhabiting the St. Johns River and exposed to different types and/or degrees of contamination. Welaka was selected as the reference site in this study because of its low urban and agricultural development, Palatka is in close proximity to a paper mill plant, the Green Cove site is influenced by marine shipping activities and Julington Creek site receives discharges of domestic wastewater and storm water runoff from recreational boating marinas. For this study, bass were sampled both prior to (September 1996) and during the spawning season (February 1997). In order to characterize chemical exposure, bass livers were analyzed for up to 90 trace organics and 11 trace metal contaminants. Reproductive parameters measured included gonadosomatic index (GSI), histological evaluation of gonads and plasma concentrations of vitellogenin (VTG), 17beta-estradiol (E2) and 11-ketotestosterone (11-KT). In general, the sum of organic chemicals was highest in livers from Palatka bass and bass from Green Cove and Julington Creek had higher hepatic concentrations of low molecular polycyclic aromatic hydrocarbons and polychlorinated biphenyls when compared to fish from Welaka. Metals were more variable across sites, with highest mean concentrations found in bass from either Julington Creek (Ag, As, Cr, Cu, Zn) or Welaka (Cd, Hg, Pb, Se, Tn). Female bass from Palatka and Green Cove had lower concentrations of E2, VTG and lower GSI in relation to Welaka. Males from Palatka and Green Cove showed comparable declines in 11-KT in relation to males from Julington Creek and GSI were decreased only in Palatka males. These results indicate a geographical trend in reproductive effects, with changes being most pronounced at the site closest to the paper mill (Palatka) and decreasing as the St. Johns River flows downstream. Since reproductive

  16. Fish fauna recovery in a newly re-flooded Mediterranean coastal lagoon

    Science.gov (United States)

    Koutrakis, Emmanuil; Sylaios, Georgios; Kamidis, Nikolaos; Markou, Dimitrios; Sapounidis, Argyris

    2009-08-01

    Drana Lagoon, located at the NW site of Evros River Delta, was drained in 1987 and re-flooded in 2004 within the framework of an integrated wetland restoration project. This study presents the results of a monitoring program of the lagoon's oceanographic, water quality and fish fauna characteristics, during the pre- and post-restoration period. Results depict the presence of high salinity water (up to 41) due to seawater intrusion, strong evaporation in its interior and inadequate freshwater inflows. Overall, nutrient levels were low depicting local changes. Tidal variability at the mouth was approximately 0.2 m, producing high velocity tidal currents (up to 0.75 m/s). Eleven fish fauna species were collected; seven species were caught in both the inlet channel and the lagoon during the pre-restoration period and nine species in the post-restoration period. Atherina boyeri (37.6%) and Pomatoschistus marmoratus (31.7%) dominated the lagoon during the post-restoration period. Most of the A. boyeri specimens (88.5%) were caught inside the lagoon, while P. marmoratus had an almost equal distribution in the inlet channel and the lagoon (56.3% and 43.7% respectively). The presence of species of the Mugilidae family (5.2% total average catches after lagoon re-flooding) was mainly in the inlet channel (12.6% of the average catches) and not inside the lagoon (only 1.3% of the average catches). The small number of fish species inhabiting the lagoon might be the result of the recent restoration or it could be related with the increased water flow observed at the lagoon mouth during the flood and ebb tidal phases, and also in the presence of a smooth bank in the concrete waterspout that connects the entrance channel with the lagoon. The limited presence of the Mugilidae juveniles inside the lagoon could be related to the prevailing tidal inlet dynamics (i.e. strong ebb flow at lagoon inlet), thus preventing the species to enter the lagoon. In order to restore the lagoon

  17. Fishes of the Taquari-Antas river basin (Patos Lagoon basin, southern Brazil Peixes da bacia do rio Taquari-Antas (sistema da Laguna dos Patos, sul do Brasil

    Directory of Open Access Journals (Sweden)

    FG. Becker

    2013-02-01

    Full Text Available The aquatic habitats of the Taquari-Antas river basin (in the Patos Lagoon basin, southern Brazil are under marked environmental transformation because of river damming for hydropower production. In order to provide an information baseline on the fish fauna of the Taquari-Antas basin, we provide a comprehensive survey of fish species based on primary and secondary data. We found 5,299 valid records of fish species in the basin, representing 119 species and 519 sampling sites. There are 13 non-native species, six of which are native to other Neotropical river basins. About 24% of the total native species are still lacking a taxonomic description at the species level. Three native long-distance migratory species were recorded (Leporinus obtusidens, Prochilodus lineatus, Salminus brasiliensis, as well as two potential mid-distance migrators (Parapimelodus nigribarbis and Pimelodus pintado. Although there is only one officially endangered species in the basin (S. brasiliensis, restricted range species (21.7% of total species should be considered in conservation efforts.Os ambientes aquáticos da Bacia do rio Taquari-Antas (Bacia da Laguna dos Patos, sul do Brasil vêm sofrendo considerável transformação, principalmente em razão da implantação de barragens para geração de energia elétrica. Com o objetivo de estabelecer um diagnóstico amplo da ictiofauna da Bacia do Taquari-Antas, realizou-se um inventário das espécies dessa bacia a partir de dados primários e secundários. Foram obtidos 5.299 registros válidos de espécies de peixe na bacia, representando 119 espécies e 519 localidades amostradas. Ocorrem, na bacia, 13 espécies não nativas, seis das quais são oriundas de outras bacias neotropicais. Cerca de 24% de todas as espécies carecem de descrição taxonômica no nível específico. Foram registradas três espécies nativas migradoras de longa distância (Leporinus obtusidens, Prochilodus lineatus e Salminus brasiliensis e

  18. Hybridization of two megacephalic map turtles (testudines: emydidae: Graptemys) in the Choctawhatchee River drainage of Alabama and Florida

    Science.gov (United States)

    Godwin, James; Lovich, Jeffrey E.; Ennen, Joshua R.; Kreiser, Brian R.; Folt, Brian; Lechowicz, Chris

    2014-01-01

    Map turtles of the genus Graptemys are highly aquatic and rarely undergo terrestrial movements, and limited dispersal among drainages has been hypothesized to drive drainage-specific endemism and high species richness of this group in the southeastern United States. Until recently, two members of the megacephalic “pulchra clade,” Graptemys barbouri andGraptemys ernsti, were presumed to be allopatric with a gap in both species' ranges in the Choctawhatchee River drainage. In this paper, we analyzed variation in morphology (head and shell patterns) and genetics (mitochondrial DNA and microsatellite loci) from G. barbouri, G. ernsti, and Graptemys sp. collected from the Choctawhatchee River drainage, and we document the syntopic occurrence of those species and back-crossed individuals of mixed ancestry in the Choctawhatchee River drainage. Our results provide a first counter-example to the pattern of drainage-specific endemism in megacephalic Graptemys. Geologic events associated with Pliocene and Pleistocene sea level fluctuations and the existence of paleo-river systems appear to have allowed the invasion of the Choctawhatchee system by these species, and the subsequent introgression likely predates any potential human-mediated introduction.

  19. Water characterization and trophic state of Chichoj Lagoon, Alta Verapaz, Guatemala

    International Nuclear Information System (INIS)

    Mourino, C.; Basterrechea, M.; Molina, S. E.; De Zepeda, M.; De Juarez, Y. C.; Aguilar, E.; Oliva, B.; Palacios, R.; Palma, J. A.; Castellanos, P.

    1993-01-01

    Chichoj lagoon has lost 71.6 ha in last 45 years, equivalent to 65% of its area on 1946. At the present, lagoon shows a great invasion of vegetation, with a trend to disappear if this process continues. Physicochemical data evaluation indicated an evident lymnological stress over lagoon due to minimal natural and significant anthropogenic contributions. Temperature was defined by physical factors as sunlight irradiation periods and caloric exchange with wind, promoting the mixing of its water between december and january. Dissolved oxygen concentrations were typical of euthrophic lakes, with over saturation in surface waters an anoxia below few meters depth describing a non-dependent temperature trend. The main affluent river contributions were oxygen-d efficient. pH behavior was related with dissolved oxygen, due to narrow relation between acidity and redox mechanisms in euthrophic waters. Lagoon and affluent river conductivities showed ionic materials contributions from basin (due to its variation with climatic changes), anthropogenic contributions (observed in affluent river) and metabolic activity from sediments speeded up in last portion of lagoon, draining great amounts of ionic substances through effluent river. Redox potentials indicated the trend of reductive process instead of oxidative ones in the affluent river and below 7 m depth in lagoon. Surface and Profile data evaluation suggested the presence of a point-source of contaminants and nutrients, and evidenced the metabolic activity produced over them in lagoon, expressed as a visual euthrophic condition. Next paper will describe nutrients and other water quality parameters behaviors and their interrelation with the physicochemical parameters described in this paper. 1 map, 5 tabs.(Author)

  20. Potentiometric Surface of the Upper Floridan Aquifer in the St. Johns River Water Management District and Vicinity, Florida, May 2009

    Science.gov (United States)

    Kinnaman, Sandra L.; Dixon, Joann F.

    2009-01-01

    This map depicts the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity for May 2009. Potentiometric contours are based on water-level measurements collected at 625 wells during the period May 14 - May 29, near the end of the dry season. Some contours are inferred from previous potentiometric-surface maps with larger well networks. The potentiometric surface of the carbonate Upper Floridan aquifer responds mainly to rainfall, and more locally, to groundwater withdrawals and spring flow. Potentiometric-surface highs generally correspond to topographic highs where the aquifer is recharged. Springs and areas of diffuse upward leakage naturally discharge water from the aquifer and are most prevalent along the St. Johns River. Areas of discharge are reflected by depressions in the potentiometric surface. Groundwater withdrawals locally have lowered the potentiometric surface. Groundwater in the Upper Floridan aquifer generally flows from potentiometric highs to potentiometric lows in a direction perpendicular to the contours.

  1. Potentiometric Surface of the Upper Floridan Aquifer in the St. Johns River Water Management District and Vicinity, Florida, May 2005

    Science.gov (United States)

    Kinnaman, Sandra L.

    2006-01-01

    INTRODUCTION This map depicts the potentiometric surface of the upper Floridan aquifer in the St. Johns River Water Management District and vicinity for May 2005. Potentiometric contours are based on water level measurements collected at 598 wens during the period May 5 - 31, near the end of the dry season. Some contours are inferred from previous potentiometric-surface maps with larger well networks. The potentiometric surface of the carbonate upper Floridan aquifer responds mainly to rainfall, and more locally, to ground water withdrawals. Potentiometric-surface highs generally correspond to topographic highs where the aquifer is recharged. Springs and areas of diffuse upward leakage naturally discharge water from the aquifer and are most prevalent along the St. Johns River. Areas of discharge are reflected by depressions in the potentiometric surface. Ground water withdrawals locally have lowered the potentiometric surface. Ground water in the upper Floridan aquifer generally flows from potentiometric highs to potentiometric lows in a direction perpendicular to the contours.

  2. Use and occurrence of pesticides in the Apalachicola-Chattahoochee-Flint River basin, Georgia, Alabama, and Florida, 1960-91

    Science.gov (United States)

    Stell, Susan M.; Hopkins, Evelyn H.; Buell, Gary R.; Hippe, Daniel J.

    1995-01-01

    The Apalachicola-Chattahoochee-Flint (ACF) River basin was one of the first 20 study units selected in 1991 by the U.S. Geological Survey for its National Water-Quality Assessment (NAWQA) program. Because pesticide contamination of surface water and ground water is a concern nationwide, a major emphasis of the NAWQA program is to examine the occurrence and distribution of pesticides in the water resources of these study unit basins. An understanding of the types and distribution of land uses; pesticide properties, pest-control practices, and pesticide use; and an evaluation of the occurrence and distribution of pesticides in the water resources of the ACF are necessary to meet this objective of the NAWQA program. This report describes land use and pesticide use at a county level, and the occurrence and distribution of pesticides in the water resources of the ACF River basin on the basis of previously-collected data. About 33 percent of the ACF River basin is used for agriculture, 16 percent is used for silviculture, and about 5 percent of the basin is in urban and suburban settings; primarily the Columbus, Albany, and Atlanta Metropolitan areas. The remainder is in wetlands and non-silvicultural forest. A broad range of synthetic-organic herbicides, insecticides, and fungicides are applied to land in agricultural, silvicultural, urban, and suburban areas. The period of intensive pesticide applications extends from March to October. Pesticide data available for the period from 1971 through 1989 in the U.S. Geological Survey National Water Information System (NWIS) and for the period from 1960 through 1991 in the U.S. Environmental Protection Agency Storage and Retrieval System (STORET) were analyzed to describe the occurrence and distribution of pesticides in water resources of the ACF River basin. Collectively, the NWIS and STORET databases contain about 19,600 individual analyses for pesticide concentration in the ACF River basin. Pesticide concentrations were at

  3. An integrated approach to investigate the hydrological behavior of the Santa Fe River Basin, north central Florida

    Science.gov (United States)

    Vibhava, F.; Graham, W. D.; De Rooij, R.; Maxwell, R. M.; Martin, J. B.; Cohen, M. J.

    2011-12-01

    The Santa Fe River Basin (SFRB) consists of three linked hydrologic units: the upper confined region (UCR), semi-confined transitional region (Cody Escarpment, CE) and lower unconfined region (LUR). Contrasting geological characteristics among these units affect streamflow generation processes. In the UCR, surface runoff and surficial stores dominate whereas in the LCR minimal surface runoff occurs and flow is dominated by groundwater sources and sinks. In the CE region the Santa Fe River (SFR) is captured entirely by a sinkhole into the Floridan aquifer, emerging as a first magnitude spring 6 km to the south. In light of these contrasting hydrological settings, developing a predictive, basin scale, physically-based hydrologic simulation model remains a research challenge. This ongoing study aims to assess the ability of a fully-coupled, physically-based three-dimensional hydrologic model (PARFLOW-CLM), to predict hydrologic conditions in the SFRB. The assessment will include testing the model's ability to adequately represent surface and subsurface flow sources, flow paths, and travel times within the basin as well as the surface-groundwater exchanges throughout the basin. In addition to simulating water fluxes, we also are collecting high resolution specific conductivity data at 10 locations throughout the river. Our objective is to exploit hypothesized strong end-member separation between riverine source water geochemistry to further refine the PARFLOW-CLM representation of riverine mixing and delivery dynamics.

  4. A Geochemical Mass-Balance Method for Base-Flow Separation, Upper Hillsborough River Watershed, West-Central Florida, 2003-2005 and 2009

    Science.gov (United States)

    Kish, G.R.; Stringer, C.E.; Stewart, M.T.; Rains, M.C.; Torres, A.E.

    2010-01-01

    Geochemical mass-balance (GMB) and conductivity mass-balance (CMB) methods for hydrograph separation were used to determine the contribution of base flow to total stormflow at two sites in the upper Hillsborough River watershed in west-central Florida from 2003-2005 and at one site in 2009. The chemical and isotopic composition of streamflow and precipitation was measured during selected local and frontal low- and high-intensity storm events and compared to the geochemical and isotopic composition of groundwater. Input for the GMB method included cation, anion, and stable isotope concentrations of surface water and groundwater, whereas input for the CMB method included continuous or point-sample measurement of specific conductance. The surface water is a calcium-bicarbonate type water, which closely resembles groundwater geochemically, indicating that much of the surface water in the upper Hillsborough River basin is derived from local groundwater discharge. This discharge into the Hillsborough River at State Road 39 and at Hillsborough River State Park becomes diluted by precipitation and runoff during the wet season, but retains the calcium-bicarbonate characteristics of Upper Floridan aquifer water. Field conditions limited the application of the GMB method to low-intensity storms but the CMB method was applied to both low-intensity and high-intensity storms. The average contribution of base flow to total discharge for all storms ranged from 31 to 100 percent, whereas the contribution of base flow to total discharge during peak discharge periods ranged from less than 10 percent to 100 percent. Although calcium, magnesium, and silica were consistent markers of Upper Floridan aquifer chemistry, their use in calculating base flow by the GMB method was limited because the frequency of point data collected in this study was not sufficient to capture the complete hydrograph from pre-event base-flow to post-event base-flow concentrations. In this study, pre-event water

  5. Assessing hog lagoon waste contamination in the Cape Fear Watershed using Bacteroidetes 16S rRNA gene pyrosequencing.

    Science.gov (United States)

    Arfken, Ann M; Song, Bongkeun; Mallin, Michael A

    2015-09-01

    Hog lagoons can be major sources of waste and nutrient contamination to watersheds adjacent to pig farms. Fecal source tracking methods targeting Bacteroidetes 16S rRNA genes in pig fecal matter may underestimate or fail to detect hog lagoon contamination in riverine environments. In order to detect hog lagoon wastewater contamination in the Cape Fear Watershed, where a large number of hog farms are present, we conducted pyrosequencing analyses of Bacteroidetes 16S rRNA genes in hog lagoon waste and identified new hog lagoon-specific marker sequences. Additional pyrosequencing analyses of Bacteroidetes 16S rRNA genes were conducted with surface water samples collected at 4 sites during 5 months in the Cape Fear Watershed. Using an operational taxonomic unit (OTU) identity cutoff value of 97 %, these newly identified hog lagoon markers were found in 3 of the river samples, while only 1 sample contained the pig fecal marker. In the sample containing the pig fecal marker, there was a relatively high percentage (14.1 %) of the hog lagoon markers and a low pig fecal marker relative abundance of 0.4 % in the Bacteroidetes 16S rRNA gene sequences. This suggests that hog lagoon contamination must be somewhat significant in order for pig fecal markers to be detected, and low levels of hog lagoon contamination cannot be detected targeting only pig-specific fecal markers. Thus, new hog lagoon markers have a better detection capacity for lagoon waste contamination, and in conjunction with a pig fecal marker, provide a more comprehensive and accurate detection of hog lagoon waste contamination in susceptible watersheds.

  6. Water quality assessment and apportionment of pollution sources using APCS-MLR and PMF receptor modeling techniques in three major rivers of South Florida.

    Science.gov (United States)

    Haji Gholizadeh, Mohammad; Melesse, Assefa M; Reddi, Lakshmi

    2016-10-01

    In this study, principal component analysis (PCA), factor analysis (FA), and the absolute principal component score-multiple linear regression (APCS-MLR) receptor modeling technique were used to assess the water quality and identify and quantify the potential pollution sources affecting the water quality of three major rivers of South Florida. For this purpose, 15years (2000-2014) dataset of 12 water quality variables covering 16 monitoring stations, and approximately 35,000 observations was used. The PCA/FA method identified five and four potential pollution sources in wet and dry seasons, respectively, and the effective mechanisms, rules and causes were explained. The APCS-MLR apportioned their contributions to each water quality variable. Results showed that the point source pollution discharges from anthropogenic factors due to the discharge of agriculture waste and domestic and industrial wastewater were the major sources of river water contamination. Also, the studied variables were categorized into three groups of nutrients (total kjeldahl nitrogen, total phosphorus, total phosphate, and ammonia-N), water murkiness conducive parameters (total suspended solids, turbidity, and chlorophyll-a), and salt ions (magnesium, chloride, and sodium), and average contributions of different potential pollution sources to these categories were considered separately. The data matrix was also subjected to PMF receptor model using the EPA PMF-5.0 program and the two-way model described was performed for the PMF analyses. Comparison of the obtained results of PMF and APCS-MLR models showed that there were some significant differences in estimated contribution for each potential pollution source, especially in the wet season. Eventually, it was concluded that the APCS-MLR receptor modeling approach appears to be more physically plausible for the current study. It is believed that the results of apportionment could be very useful to the local authorities for the control and

  7. Zebra Mussel Farming in the Szczecin (Oder Lagoon: Water-Quality Objectives and Cost-Effectiveness

    Directory of Open Access Journals (Sweden)

    Gerald Schernewski

    2012-06-01

    Full Text Available The Oder (Szczecin Lagoon in the southern Baltic Sea is a heavily eutrophicated and degraded coastal ecosystem. We applied a systems approach framework to critically evaluate whether existing water-management measures achieve water-quality objectives for the river and lagoon systems. Our simulations reveal that the existing water-quality objectives for the river and the coastal waters are not sufficiently complementary. We suggest new water-quality threshold concentrations, which are in agreement with the European Water Framework Directive, and we calculate acceptable maximum nutrient loads for the Oder River. These calculations suggest that external nutrient-load reductions in the river basin alone seem insufficient to achieve good water quality in the lagoon. A comprehensive eutrophication management approach should also include internal nutrient-retention and nutrient-removal measures in the lagoon. We focus on mussel farming, i.e., that of zebra mussels, Dreissena polymorpha, because they are efficient in removing nutrients and improving water transparency in the Oder Lagoon. For this purpose, the ecosystem model ERGOM is extended by a mussel module and an economic model. The economic model describes costs and benefits of mussel cultivation depending on the the farm size. We included additional potential sources of income such as water-quality tax or emission certificates. The simulations show that mussel farming in the lagoon is a suitable supportive measure and, at a load-reduction target of 50% or more, it is a cost-efficient measure for removing nutrients and for implementing the Baltic Sea Action Plan. In the Oder Lagoon, mussel farming could potentially remove nearly 1000 t of N (70 t of P/year, or about 2% of the present N and P loads, and it would have the additional benefit of improving water transparency.

  8. Whole genome sequence analysis of an Alachlor and Endosulfan degrading Pseudomonas strain W15Feb9B isolated from Ochlockonee River, Florida

    Directory of Open Access Journals (Sweden)

    Ashvini Chauhan

    2016-06-01

    Full Text Available We recently isolated a Pseudomonas sp. strain W15Feb9B from Ochlockonee River, Florida and demonstrated potent biodegradative activity against two commonly used pesticides - Alachlor [(2-chloro-2′,6′-diethylphenyl-N (methoxymethylacetanilide] and Endosulfan [(6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9methano-2,3,4-benzo(edi-oxathiepin-3-oxide], respectively. To further identify the repertoire of metabolic functions possessed by strain W15Feb9B, a draft genome sequence was obtained, assembled, annotated and analyzed. The genome sequence of strain 2385 has been deposited in GenBank under accession number JTKF00000000; BioSample number SAMN03151543. The sequences obtained from strain 2385 assembled into 192 contigs with a genome size of 6,031,588, G + C content of 60.34, and 5512 total number of putative genes. RAST annotated a total of 542 subsystems in the genome of strain W15Feb9B along with the presence of 5360 coding sequences. A genome wide survey of strain W15Feb9B indicated that it has the potential to degrade several other pollutants including atrazine, caprolactam, dioxin, PAHs (such as naphthalene and several chloroaromatic compounds.

  9. Potentiometric surface of the Upper Floridan aquifer in the St. Johns River water management district and vicinity, Florida, September 2005

    Science.gov (United States)

    Kinnaman, Sandra L.

    2006-01-01

    This map depicts the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity for September 2005. Potentiometric contours are based on water-level measurements collected at 643 wells during the period September 12-28, near the end of the wet season. Some contours are inferred from previous potentiometric-surface maps with larger well networks. The potentiometric surface of the carbonate Upper Floridan aquifer responds mainly to rainfall, and more locally, to ground-water withdrawals and springflow. Potentiometric-surface highs generally correspond to topographic highs where the aquifer is recharged. Springs and areas of diffuse upward leakage naturally discharge water from the aquifer and are most prevalent along the St. Johns River. Areas of discharge are reflected by depressions in the potentiometric surface. Ground-water withdrawals locally have lowered the potentiometric surface. Ground water in the Upper Floridan aquifer generally flows from potentiometric highs to potentiometric lows in a direction perpendicular to the contours.

  10. Potentiometric Surface of the Upper Floridan Aquifer in the St. Johns River Water Management District and Vicinity, Florida, September 2008

    Science.gov (United States)

    Kinnaman, Sandra L.; Dixon, Joann F.

    2009-01-01

    This map depicts the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity for September 2008. Potentiometric contours are based on water-level measurements collected at 589 wells during the period September 15-25, near the end of the wet season. Some contours are inferred from previous potentiometric-surface maps with larger well networks. The potentiometric surface of the carbonate Upper Floridan aquifer responds mainly to rainfall, and more locally, to ground-water withdrawals and spring flow. Potentiometric-surface highs generally correspond to topographic highs where the aquifer is recharged. Springs and areas of diffuse upward leakage naturally discharge water from the aquifer and are most prevalent along the St. Johns River. Areas of discharge are reflected by depressions in the potentiometric surface. Ground-water withdrawals locally have lowered the potentiometric surface. Ground water in the Upper Floridan aquifer generally flows from potentiometric highs to potentiometric lows in a direction perpendicular to the contours.

  11. Potentiometric Surface of the Upper Floridan Aquifer in the St. Johns River Water Management District and Vicinity, Florida, September 2007

    Science.gov (United States)

    Kinnaman, Sandra L.; Dixon, Joann F.

    2008-01-01

    This map depicts the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity for September 2007. Potentiometric contours are based on water-level measurements collected at 554 wells during the period September 15-27, near the end of the wet season. Some contours are inferred from previous potentiometric-surface maps with larger well networks. The potentiometric surface of the carbonate Upper Floridan aquifer responds mainly to rainfall, and more locally, to ground-water withdrawals and spring flow. Potentiometric-surface highs generally correspond to topographic highs where the aquifer is recharged. Springs and areas of diffuse upward leakage naturally discharge water from the aquifer and are most prevalent along the St. Johns River. Areas of discharge are reflected by depressions in the potentiometric surface. Ground-water withdrawals locally have lowered the potentiometric surface. Ground water in the Upper Floridan aquifer generally flows from potentiometric highs to potentiometric lows in a direction perpendicular to the contours.

  12. Potentiometric surface of the upper Floridan Aquifer in the St. Johns River Water Management District and vicinity, Florida, September, 2004

    Science.gov (United States)

    Kinnaman, Sandra L.

    2005-01-01

    Introduction: This map depicts the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity in September 2004. Potentiometric contours are based on water-level measurements collected at 608 wells during the period September 14-October 1, near the end of the wet season. The shapes of some contours have been inferred from previous potentiometric-surface maps with larger well networks. The potentiometric surface of the carbonate Upper Floridan aquifer responds mainly to rainfall, and more locally, to ground-water withdrawals. Potentiometric-surface highs generally correspond to topographic highs where the aquifer is recharged. Springs and areas of diffuse upward leakage naturally discharge water from the aquifer and are most prevalent along the St. Johns River. Areas of discharge are reflected by depressions in the potentiometric surface. Ground-water withdrawals locally have lowered the potentiometric surface. Ground water in the Upper Floridan aquifer generally flows from potentiometric highs to potentiometric lows in a direction perpendicular to the contours.

  13. Potentiometric Surface of the Upper Floridan Aquifer in the St. Johns River Water Management District and Vicinity, Florida, May, 2004

    Science.gov (United States)

    Kinnaman, Sandra L.; Knowles, Leel

    2004-01-01

    INTRODUCTION This map depicts the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity in May 2001. Potentiometric contours are based on water-level measurements collected at 684 wells during the period May 2 - 30, near the end of the dry season. The shapes of some contours have been inferred from previous potentiometric-surface maps with larger well networks. The potentiometric surface of the carbonate Upper Floridan aquifer responds mainly to rainfall, and more locally, to ground-water withdrawals. Potentiometric-surface highs generally correspond to topographic highs where the aquifer is recharged. Springs and areas of diffuse upward leakage naturally discharge water from the aquifer and are most prevalent along the St. Johns River. Areas of discharge are reflected by depressions in the potentiometric surface. Ground-water withdrawals locally have lowered the potentiometric surface. Ground water in the Upper Floridan aquifer generally flows from potentiometric highs to potentiometric lows in a direction perpendicular to the contours.

  14. Potentiometric Surface of the Upper Floridan Aquifer in the St. Johns River Water Management District and Vicinity, Florida, September 2006

    Science.gov (United States)

    Kinnaman, Sandra L.; Dixon, Joann F.

    2007-01-01

    Introduction This map depicts the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity for September 2006. Potentiometric contours are based on water-level measurements collected at 571 wells during the period September 11-29, near the end of the wet season. Some contours are inferred from previouspotentiometric-surface maps with larger well networks. The potentiometric surface of the carbonate Upper Floridan aquifer responds mainly to rainfall, and more locally, to ground-water withdrawals and spring flow. Potentiometric-surface highs generally correspond to topographic highs where the aquifer is recharged. Springs and areas of diffuse upward leakage naturally discharge water from the aquifer and are most prevalent along the St. Johns River. Areas of discharge are reflected by depressions in the potentiometric surface. Ground-water withdrawals locally have lowered the potentiometric surface. Ground water in the Upper Floridan aquifer generally flows from potentiometric highs to potentiometric lows in a direction perpendicular to the contours.

  15. Potentiometric Surface of the Upper Floridan Aquifer in the St. Johns River Water Management District and Vicinity, Florida, May 2006

    Science.gov (United States)

    Kinnaman, Sandra L.

    2006-01-01

    Introduction: This map depicts the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity for May 2006. Potentiometric contours are based on water-level measurements collected at 599 wells during the period May 14-31, near the end of the dry season. Some contours are inferred from previous potentiometric-surface maps with larger well networks. The potentiometric surface of the carbonate Upper Floridan aquifer responds mainly to rainfall, and more locally, to ground-water withdrawals and springflow. Potentiometric-surface highs generally correspond to topographic highs where the aquifer is recharged. Springs and areas of diffuse upward leakage naturally discharge water from the aquifer and are most prevalent along the St. Johns River. Areas of discharge are reflected by depressions in the potentiometric surface. Ground-water withdrawals locally have lowered the potentiometric surface. Ground water in the Upper Floridan aquifer generally flows from potentiometric highs to potentiometric lows in a direction perpendicular to the contours.

  16. Potentiometric Surface of the Upper Floridan Aquifer in the St. Johns River Water Management District and Vicinity, Florida, May 2007

    Science.gov (United States)

    Kinnaman, Sandra L.; Dixon, Joann F.

    2007-01-01

    Introduction This map depicts the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity for May 2007. Potentiometric contours are based on water-level measurements collected at 566 wells during the period May 4-June 11 near the end of the dry season, however most of the water level data for this map were collected by the U.S. Geological Survey during the period May 21-25, 2007. Some contours are inferred from previous potentiometric-surface maps with larger well networks. The potentiometric surface of the carbonate Upper Floridan aquifer responds mainly to rainfall, and more locally, to ground-water withdrawals and spring flow. Potentiometric-surface highs generally correspond to topographic highs where the aquifer is recharged. Springs and areas of diffuse upward leakage naturally discharge water from the aquifer and are most prevalent along the St. Johns River. Areas of discharge are reflected by depressions in the potentiometric surface. Ground-water withdrawals locally have lowered the potentiometric surface. Ground water in the Upper Floridan aquifer generally flows from potentiometric highs to potentiometric lows in a direction perpendicular to the contours.

  17. CRECIMIENTO Y POTENCIAL REPRODUCTIVO DE LA BORA ( Eichhornia crassipes (Mart. Solms ( PONTEDER I ACEA E EN ALGUNAS LAGUNAS DE LA PLANICIE DE INUNDACIÓN DEL TRAMO MEDIO, RÍO ORINOCO, VENEZUELA I GROWTH AND REPRODUCTIVE POTENTIAL OF WATER HYACINTH ( Eichhornia crassipes (Mart. SOLMS (PONTEDERIACEAE IN SOME LAGOONS AT FLOODPLAIN OF THE MIDDLE ORINOCO RIVER, VENEZUELA

    Directory of Open Access Journals (Sweden)

    Julio C. Rodríguez R.

    2018-05-01

    Full Text Available The water hyacinth ( Eichhornia crassipes grows naturally in some floodplains of the middle Orinoco River. Its widespread distribution and biomass is causing a great impact in the towns near these lentic ecosystems. The vegetative growth, floral biology and fecundity of E. crassipes were determined in the Castillero, Teja and Tejita lagoons near Caicara del Orinoco, from January to July 2005, during the dry season. Plants were placed at initial density of five rosettes in floating baskets in the floodplains and the number of daughter plants (g. m -2 and dry biomass m-2 were determined at fifteen, thirty, sixty and ninety days after seeding. The number of plants with and without flowers or fructified were counted in areas of the lagoons with the highest flowering intensity. The spatial distribution of stamens in relation to the stigma were observed in order to determine the presence of heterostyly. The number of water hyacinth plants and weight can double in an average of 20 and 24 days, respectively. The fastest growth rate (rossettes m -2 was found in January and February while the major growth rate in dry weight m-2 was recorded in February-May. It is frequent to find inflorescences in the dry season and occasionally in the wet season. From the kinds of heterostityly only plants with mesostyle flowers were found . The reproduction of water hyacinth is mainly vegetative and seeds are scarcely found in the capsules

  18. The lagoon a study in imagery The lagoon a study in imagery

    Directory of Open Access Journals (Sweden)

    Carmen Gago Alvarez

    2008-04-01

    Full Text Available The purpose of this paper is to prove that, through exuberant sensuous imagery - the strange tropical setting, the mystery of elements, light and darkness - Joseph Conrad, in his short-story "The Lagoon" describes and transmits Impressionistically, the dramatic story of a men surprised by his own act of cowardice, a man divided between loyalty to his own blood and love. This man, Arsat suffers a blockaded feeling towards himself because he failed to act when he had the occasion, and he missed it: he left his brother to die in the hands of the enemy while he. Arsat, escaped with his love Diamelen, to live in the "shadows" of "The Lagoon" - his own psychological, subconscious guilty conscience. The story starts with a description of nature, as motionless, and undefined as the plot still is: The forests, somber and dull, stood motionless and silent... In the stillness of the air ... minute blossoms seemed do have been bewitched into an immobility perfect and final. Nothing moved on the river (1 The purpose of this paper is to prove that, through exuberant sensuous imagery - the strange tropical setting, the mystery of elements, light and darkness - Joseph Conrad, in his short-story "The Lagoon" describes and transmits Impressionistically, the dramatic story of a men surprised by his own act of cowardice, a man divided between loyalty to his own blood and love. This man, Arsat suffers a blockaded feeling towards himself because he failed to act when he had the occasion, and he missed it: he left his brother to die in the hands of the enemy while he. Arsat, escaped with his love Diamelen, to live in the "shadows" of "The Lagoon" - his own psychological, subconscious guilty conscience. The story starts with a description of nature, as motionless, and undefined as the plot still is: The forests, somber and dull, stood motionless and silent... In the stillness of the air ... minute blossoms seemed do have been bewitched into an

  19. Metagenomes of Mediterranean coastal lagoons.

    Science.gov (United States)

    Ghai, Rohit; Hernandez, Claudia Mella; Picazo, Antonio; Mizuno, Carolina Megumi; Ininbergs, Karolina; Díez, Beatriz; Valas, Ruben; DuPont, Christopher L; McMahon, Katherine D; Camacho, Antonio; Rodriguez-Valera, Francisco

    2012-01-01

    Coastal lagoons, both hypersaline and freshwater, are common, but still understudied ecosystems. We describe, for the first time, using high throughput sequencing, the extant microbiota of two large and representative Mediterranean coastal lagoons, the hypersaline Mar Menor, and the freshwater Albufera de Valencia, both located on the south eastern coast of Spain. We show there are considerable differences in the microbiota of both lagoons, in comparison to other marine and freshwater habitats. Importantly, a novel uncultured sulfur oxidizing Alphaproteobacteria was found to dominate bacterioplankton in the hypersaline Mar Menor. Also, in the latter prokaryotic cyanobacteria were almost exclusively comprised by Synechococcus and no Prochlorococcus was found. Remarkably, the microbial community in the freshwaters of the hypertrophic Albufera was completely in contrast to known freshwater systems, in that there was a near absence of well known and cosmopolitan groups of ultramicrobacteria namely Low GC Actinobacteria and the LD12 lineage of Alphaproteobacteria.

  20. Modelling the salinization of a coastal lagoon-aquifer system

    Science.gov (United States)

    Colombani, N.; Mastrocicco, M.

    2017-08-01

    In this study, a coastal area constituted by alternations of saline-brackish lagoons and freshwater bodies was studied and modelled to understand the hydrological processes occurring between the lagoons, the groundwater system of the Po River Delta (Italy) and the Adriatic Sea. The contribution of both evaporation and anthropogenic factors on groundwater salinization was assessed by means of soil, groundwater and surface water monitoring. Highresolution multi-level samplers were used to capture salinity gradients within the aquifer and surface water bodies. Data were employed to calibrate a density-dependent numerical transport model implemented with SEAWAT code along a transect perpendicular to the coast line. The results show that the lagoon is hydraulically well connected with the aquifer, which provides the major source of salinity because of the upcoming of paleo-seawater from the aquitard laying at the base of the unconfined aquifer. On the contrary, the seawater (diluted by the freshwater river outflow) creates only a limited saltwater wedge. The increase in groundwater salinity could be of serious concern, especially for the pinewood located in the dune near the coast, sensitive to salinity increases. This case study represents an interesting paradigm for other similar environmental setting, where the assumption of classical aquifer salinization from a saltwater wedge intruding from the sea is often not representative of the actual aquifer’s salinization mechanisms.

  1. Metals in some lagoons of Mexico.

    Science.gov (United States)

    Vazquez, F G; Sharma, V K; Alexander, V H; Frausto, C A

    1995-02-01

    The concentrations of metals, Cd, Cu, Fe, Mn, Ni, Pb, and Zn were determined in some lagoons to establish the level of metal pollution. The lagoons studied were Alvarado lagoon, Veracruz; San Andres lagoon, Tamaulipas; and Terminos lagoon, Campeche. The concentrations were determined in water, oyster (Crassostrea virginica), and sediments. Metals were accumulated in either oysters or sediments. Cu and Zn were higher in oysters and Fe and Mn were higher in sediments. The results in water samples were compared with the limit established by the Secretaria de Ecologia and Desarrollo Urbano Report and briefly discussed.

  2. Recharge and discharge areas of the Floridan Aquifer in the St. Johns River Water Management District and vicinity, Florida

    Science.gov (United States)

    Phelps, G.G.

    1984-01-01

    The Floridan aquifer is the principal source of most of the freshwater used in the St. Johns River Water Management District. An important step in managing water resources is the delineation of recharge and discharge areas. Geohydrologic factors to be considered when delineating recharge and discharge areas include: altitude and configuration of the potentiometric surface; direction and magnitude of the gradient between the water table and the potentiometric surface; and thickness and permeability of the overlying sediments. Recharge to the aquifer comes almost entirely from rainfall within the Water Management District. Significant recharge occurs where the aquifer is at or very near land surface, and where the overlying sediments are very permeable sand so that recharge takes place downward leakage. Recharge also occurs through sinkholes, sinkhole lakes, and other lakes that have a good connection to the aquifer. Major recharge areas are delineated on the map. Discharge occurs in areas of artesian flow (where the potentiometric surface is above land surface), primarily by diffuse upward leakage and by discharge from springs. Fifty-five springs, with total discharge of about 1,600 million gallons per day, are in the Water Management District. Areas of discharge and the location of springs are shown on the map. In 1980, total pumpage in the Water Management District was about 1,000 million gallons per day. Under predevelopment conditions, discharge by springs and upward leakage approximately balanced recharged. Additional discharge by pumpage may or may not be balanced by decreased spring discharge of increased downward leakage. Examination of long-term water level trends can indicate if recharge and discharge balance. Graphs of rainfall, water levels, and municipal pumpage for Jacksonville, Orlando, and Daytona Beach are shown on the map. (USGS)

  3. Modeling ecosystem processes with variable freshwater inflow to the Caloosahatchee River Estuary, southwest Florida. II. Nutrient loading, submarine light, and seagrasses

    Science.gov (United States)

    Buzzelli, Christopher; Doering, Peter; Wan, Yongshan; Sun, Detong

    2014-12-01

    Short- and long-term changes in estuarine biogeochemical and biological attributes are consequences of variations in both the magnitude and composition of freshwater inputs. A common conceptualization of estuaries depicts nutrient loading from coastal watersheds as the stressor that promotes algal biomass, decreases submarine light penetration, and degrades seagrass habitats. Freshwater inflow depresses salinity while simultaneously introducing colored dissolved organic matter (color or CDOM) which greatly reduces estuarine light penetration. This is especially true for sub-tropical estuaries. This study applied a model of the Caloosahatchee River Estuary (CRE) in southwest Florida to explore the relationships between freshwater inflow, nutrient loading, submarine light, and seagrass survival. In two independent model series, the loading of dissolved inorganic nitrogen and phosphorus (DIN and DIP) was reduced by 10%, 20%, 30%, and 50% relative to the base model case from 2002 to 2009 (2922 days). While external nutrient loads were reduced by lowering inflow (Q0) in the first series (Q0 series), reductions were accomplished by decreasing the incoming concentrations of DIN and DIP in the second series (NP Series). The model also was used to explore the partitioning of submarine light extinction due to chlorophyll a, CDOM, and turbidity. Results suggested that attempting to control nutrient loading by decreasing freshwater inflow could have minor effects on water column concentrations but greatly influence submarine light and seagrass biomass. This is because of the relative importance of Q0 to salinity and submarine light. In general, light penetration and seagrass biomass decreased with increased inflow and CDOM. Increased chlorophyll a did account for more submarine light extinction in the lower estuary. The model output was used to help identify desirable levels of inflow, nutrient loading, water quality, salinity, and submarine light for seagrass in the lower CRE

  4. Organochlorine pesticides in sediment and biological samples from the coastal lagoons of Nicaragua

    International Nuclear Information System (INIS)

    Montenegro, S.; Lacayo, M.; Picado, F.; Lopez, A.

    1999-01-01

    A study was carried out on the Pacific coast of Nicaragua to investigate the contamination of the coastal lagoons with residues of agricultural pesticides. Samples were taken during 1995 from the areas of Estero Real, Padre Ramos, Maderas Negras, Naranjo and Paso Caballos, and during 1996 from Aposentillo to Estero Barquito - Posoltega River. Analysis of the samples of sediment and aquatic life (fishes, oysters and bivalves) showed that they were contaminated with organochlorine pesticides. The pesticides found in the highest concentrations were toxaphene (1,734 μg.kg -1 ) and p,p-DDE (275 μg kg -1 ). These data indicate widespread contamination of the ecosystem with organochlorine pesticides in the main Pacific coastal lagoons of Nicaragua, resulting from intensive agricultural use of pesticides during the past decades. The contamination has been carried from the agricultural areas to the coastal lagoons by the rivers passing through the cultivated areas. (author)

  5. Changes in abiotic characteristics of water in the Paranapanema River and three lateral lagoons at mouth zone of the Jurumirim Reservoir during the flood period, São Paulo, Brazil Cambios de las características abióticas del agua del río Paranapanema y de tres lagunas laterales en la zona de la boca de la Reserva de Jurumirim durante el periodo de inundación, São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Danielli Cristina Granado

    2012-03-01

    Full Text Available Floods increase the similarity of the abiotic water characteristics of the rivers with those of the surrounding floodplains and are the main factors that influence the ecosystem dynamics. The aim of this paper was to examine the alterations in abiotic characteristics of the Paranapanema River and three lateral lagoons with different degrees of connectivity to the river during the flood period. Samplings were performed twice a week during a three-month period. Water quality in the Camargo and Coqueiral lagoons, connected to the Paranapanema River, presented patterns of variation similar to those of the lotic ecosystem, evidenced by the principal component analysis. In Cavalos Lagoon, changes in water quality were observed in all the environments, such as a function of dilution after the water level increased and greater nutrients resulting from littoral plant decomposition after submersion. In conclusion, the marginal lagoons and river were influenced by two anthropogenic actions: water storage in a dam reservoir, which acted like a buffer against hydrological pulses, and the widening of the channel uniting Camargo Lagoon with the river, changing the connectivity level and causing an ever-greater similarity of the lagoon with the lotic system.Las inundaciones asemejan las características abióticas del agua de los ríos a la de los entornos de planicies aluviales y son los principales factores que influyen en la dinámica del ecosistema. El objetivo de este trabajo fue analizar las alteraciones en las características abióticas del río Paranapanema y de tres lagunas laterales con distintos niveles de conectividad al río durante el período de inundación. Los muestreos se realizaron dos veces por semana durante un período de tres meses. La calidad del agua en las lagunas Camargo y Coqueiral, conectadas al río Paranapanema, presentó patrones de variación similar a aquellos del ecosistema lótico, demostrado por medio de análisis de

  6. Spatial and temporal distribution of fish larvae in marginal lagoons of Pantanal, Mato Grosso State, Brazil

    Directory of Open Access Journals (Sweden)

    Karina Keyla Tondato

    Full Text Available An analysis was made of the spatial and temporal distribution of the abundance and composition of fish larvae assemblies, aiming to ascertain correlations with biotic and abiotic factors in marginal lagoons of the Cuiabá River floodplain in Brazil's Pantanal wetlands. Samples were collected bimonthly in the pelagic region of the marginal lagoons (fourteen lagoons close to the littoral zone covered by aquatic macrophytes from December 2006 to April 2007. The captured individuals consisted of 2,739 larvae, represented predominantly by Triportheus spp. (Characidae, Parodontidae, Anostomidae, Characidae and Serrasalmidae. Larval density varied among the sample lagoons in December, but the biotic (zooplankton density and abiotic (water temperature, electrical conductivity, dissolved oxygen, pH, water transparency and lagoon depth factors did not significantly affect larval composition and abundance. Larvae were captured throughout the sample period, with the highest densities occurring in December and early January. Temporally, lagoon depth, water transparency and fluviometric level showed a negative correlation with larval density. Both the zooplankton and the larval density vary positively, responding likewise to the environmental conditions imposed by flooding. The highest larval density was also found to coincide with the first rains (early December, when the rainfall has not yet reached its peak.

  7. Mud deposit formation on the open coast of the larger Patos Lagoon-Cassino Beach system

    Science.gov (United States)

    Vinzon, S. B.; Winterwerp, J. C.; Nogueira, R.; de Boer, G. J.

    2009-03-01

    This paper proposes an explanation of the mud deposits on the inner Shelf of Cassino Beach, South Brazil, by using computational modeling. These mud deposits are mainly formed by sediments delivered from Patos Lagoon, a coastal lagoon connected to the Shelf, next to Cassino Beach. The deposits are characterized by (soft) mud layers of about 1 m thick and are found between the -5 and -20 isobaths. Two hydrodynamic models of the larger Patos Lagoon-Cassino Beach system were calibrated against water elevation measured for a 5 months period, and against currents and salinity measured for a week period. The circulation patterns and water exchange through the mouth were analyzed as a function of local and remote wind effects, and river discharges. The remote wind effect mainly governs the quantity of water exchange with the Lagoon through its effect on mean sea level as a result of Ekman dynamics, while river discharges are important for the salinity of the exchanged water masses. Local winds augment the export-import rates by set-up and set-down within the Lagoon, but their effects are much smaller than those of the remote wind. Currents patterns on the inner Shelf during water outflow revealed a recirculation zone south of the Lagoon, induced by the local geometry and bathymetry of the system. This recirculation zone coincides with observed locations of mud deposition. Water, hence suspended sediment export occurs when remote and local winds are from the N-E, which explains why fine sediment deposits are mainly found south of the Lagoon's breakwater. A sensitivity analysis with the numerical model quantified the contribution of the various mechanisms driving the transport and fate of the fine suspended sediments, i.e. the effects of remote and local wind, of the astronomical tide, of river discharge and fresh-salt water-induced density currents, and of earth rotation. It is concluded that gravitational circulation and earth rotation affects the further dispersion of

  8. Estrogenic potential of the Venice, Italy, lagoon waters.

    Science.gov (United States)

    Pojana, Giulio; Bonfà, Angela; Busetti, Francesco; Collarin, Anna; Marcomini, Antonio

    2004-08-01

    The exposure of the Venice lagoon (Italy) to endocrine-disrupting compounds (EDCs) from different sources was investigated. Spatial and time distribution of EDC concentrations were determined in four sampling sessions (December 2001-May 2002) by solid phase extraction followed by high-performance liquid chromatography separation coupled with mass spectrometry detection via electrospray interface (SPE-HPLC-ESI-MS), which allowed identification of natural (estradiol, estrone) and synthetic estrogenic compounds, both steroidal (ethinylestradiol, mestranol) and nonsteroidal (benzophenone, bisphenol-A, nonylphenol, nonylphenol monoethoxylate carboxylate). No significant differences in the EDC distribution were observed between stations located near selected sources (raw sewage from the historical center of Venice, treated municipal and industrial effluents from sewage treatment plants, and areas undergoing the inflow of rivers). While synthetic nonsteroidal analytes were recorded in the 1 to 1040 ng/L range (average concentration: 34 ng/L), steroidal EDC (estradiol, ethinylestradiol) concentrations were lower (1-125 ng/L; average concentration: 8 ng/L). The estrogenic activity of lagoon waters was estimated in terms of estradiol equivalent concentration (EEQ) by applying the estradiol equivalency factors (EEFs). Steroidal EDCs (estradiol, ethinylestradiol) contributed >97% to the total potential estrogenicity of the waters, which accounted for 4 to 172 ng/L (average: 25 ng/L), as total EEQs. These levels are likely to pose adverse effects on the Venice lagoon aquatic organisms.

  9. The role of ocean tides on groundwater-surface water exchange in a mangrove-dominated estuary: Shark River Slough, Florida Coastal Everglades, USA

    Science.gov (United States)

    Smith, Christopher G.; Price, René M.; Swarzenski, Peter W.; Stalker, Jeremy C.

    2016-01-01

    Low-relief environments like the Florida Coastal Everglades (FCE) have complicated hydrologic systems where surface water and groundwater processes are intimately linked yet hard to separate. Fluid exchange within these lowhydraulic-gradient systems can occur across broad spatial and temporal scales, with variable contributions to material transport and transformation. Identifying and assessing the scales at which these processes operate is essential for accurate evaluations of how these systems contribute to global biogeochemical cycles. The distribution of 222Rn and 223,224,226Ra have complex spatial patterns along the Shark River Slough estuary (SRSE), Everglades, FL. High-resolution time-series measurements of 222Rn activity, salinity, and water level were used to quantify processes affecting radon fluxes out of the mangrove forest over a tidal cycle. Based on field data, tidal pumping through an extensive network of crab burrows in the lower FCE provides the best explanation for the high radon and fluid fluxes. Burrows are irrigated during rising tides when radon and other dissolved constituents are released from the mangrove soil. Flushing efficiency of the burrows—defined as the tidal volume divided by the volume of burrows— estimated for the creek drainage area vary seasonally from 25 (wet season) to 100 % (dry season) in this study. The tidal pumping of the mangrove forest soil acts as a significant vector for exchange between the forest and the estuary. Processes that enhance exchange of O2 and other materials across the sediment-water interface could have a profound impact on the environmental response to larger scale processes such as sea level rise and climate change. Compounding the material budgets of the SRSE are additional inputs from groundwater from the Biscayne Aquifer, which were identified using radium isotopes. Quantification of the deep groundwater component is not obtainable, but isotopic data suggest a more prevalent signal in the dry

  10. Airborne Lidar Measurements of Below-canopy Surface Water Height , Slope and Optical Properties in the Florida Everglades Shark River Slough

    Science.gov (United States)

    Dabney, P.; Harding, D. J.; Valett, S. R.; Yu, A. W.; Feliciano, E. A.; Neuenschwander, A. L.; Pitts, K.

    2015-12-01

    with 8 cm ranging precision, the surface altimetry data is acquired with very high spatial and vertical resolution. Examples of these capabilities will be shown using data collected in 2011 along and across the flow axis of the Florida Everglades Shark River Slough, targeting the slough's Long Term Ecology Research (LTER) field sites.

  11. Sludge storage lagoon biogas recovery and use

    Energy Technology Data Exchange (ETDEWEB)

    Muller, D.; Norville, C. (Memphis and Shelby County Div. of Planning and Development, TN (United States))

    1991-07-01

    The City of Memphis has two wastewater treatment plants. The SWTP employs two large anaerobic digestion sludge lagoons as part of the overall sludge treatment system. Although these lagoons are effective in concentrating and digesting sludge, they can generate offensive odors. The SWTP uses aerobic digesters to partially stabilize the sludge and help reduce objectionable odors before it enters the lagoons. The anaerobic digestion of sludge in the lagoons results in the dispersion of a large quantity of biogas into the atmosphere. The City realized that if the lagoons could be covered, the odor problem could be resolved, and at the same, time, biogas could be recovered and utilized as a source of energy. In 1987, the City commissioned ADI International to conduct a feasibility study to evaluate alternative methods of covering the lagoons and recovering and utilizing the biogas. The study recommended that the project be developed in two phases: (1) recovery of the biogas and (2) utilization of the biogas. Phase 1 consists of covering the two lagoons with an insulated membrane to control odor and temperature and collect the biogas. Phase 1 was found to be economically feasible and offered a unique opportunity for the City to save substantial operating costs at the treatment facility. The Memphis biogas recovery project is the only application in the world where a membrane cover has been used on a municipal wastewater sludge lagoon. It is also the largest lagoon cover system in the world.

  12. Occurrence and Distribution of Pesticides in the St. Lucie River Watershed, South-Central Florida, 2000-01, Based on Enzyme-Linked Immunosorbent Assay (ELISA) Screening

    Science.gov (United States)

    Lietz, A.C.

    2003-01-01

    The St. Lucie River watershed is a valuable estuarine ecosystem and resource in south-central Florida. The watershed has undergone extensive changes over the last century because of anthropogenic activities. These activities have resulted in a complex urban and agricultural drainage network that facilitates the transport of contaminants, including pesticides, to the primary canals and then to the estuary. Historical data indicate that aquatic life criteria for selected pesticides have been exceeded. To address this concern, a reconnaissance was conducted to assess the occurrence and distribution of selected pesticides within the St. Lucie River watershed. Numerous water samples were collected from 37 sites among various land-use categories (urban/built-up, citrus, cropland/pastureland, and inte-grated). Samples were collected at inflow points to primary canals (C-23, C-24, and C-44) and at control structures along these canals from October 2000 to September 2001. Samples were screened for four pesticide classes (triazines, chloroacetanilides, chlorophenoxy compounds, and organophosphates) by using Enzyme-Linked Immunosorbent Assay (ELISA) screening. A temporal distribution of pesticides within the watershed was made based on samples collected at the integrated sites during different rainfall events between October 2000 and September 2001. Triazines were detected in 32 percent of the samples collected at the integrated sites. Chloroacetanilides were detected in 60 percent of the samples collected at the integrated sites, with most detections occurring at one site. Chlorophenoxy compounds were detected in 17 percent of the samples collected at the integrated sites. Organophosphates were detected in only one sample. A spatial distribution and range of concentration of pesticides at the 37 sampling sites in the watershed were determined among land-use categories. Triazine concentrations ranged from highest to lowest in the citrus, urban/built-up, and integrated areas

  13. Environmental changes induced by human activities in the Northern Curonian Lagoon (Eastern Baltic: diatoms and stable isotope data

    Directory of Open Access Journals (Sweden)

    Giedrė Vaikutienė

    2017-05-01

    Full Text Available A sediment core collected from the northwestern part of the Curonian Lagoon, which was deposited approximately during 1800-2002, was analysed for several proxy records. Changes in diatom assemblages and carbon, nitrogen and oxygen stable isotopes (δ13C, δ15N and δ18O revealed two periods, which are characterized by differences in the sedimentation rate, sediment type and trophic state of the northern part of the Curonian Lagoon. Low δ15N values in organics and prevailing fresh-brackish benthic diatoms indicate low enrichment in the shallow, freshwater lagoon during the period 1800-1955. The eutrophic conditions in this shallow lagoon are reflected by a high abundance of planktonic diatoms common in nutrient-rich basins and increased d15N values in organics of the sediments since 1955. Starting approximately in the 1960s, decreased freshwater run-off and increased brackish-water inflow into the lagoon were observed. These changes were likely caused by the construction of the hydropower station (and a reservoir near the Nemunas River and the artificial deepening of the Klaipėda Strait during 1960-1962 and later, also by the rising sea level in the SE Baltic. The changed river run-off and the artificially deepened strait significantly influenced the fresh-brackish water circulation and environmental conditions in the northern part of the Curonian Lagoon in the last decades.

  14. Water Use in Florida, 2005 and Trends 1950-2005

    Science.gov (United States)

    Marella, Richard L.

    2008-01-01

    Water is among Florida's most valued resources. The State has more than 1,700 streams and rivers, 7,800 freshwater lakes, 700 springs, 11 million acres of wetlands, and underlying aquifers yielding quantities of freshwater necessary for both human and environmental needs (Fernald and Purdum, 1998). Although renewable, these water resources are finite, and continued growth in population, tourism, and agriculture will place increased demands on these water supplies. The permanent population of Florida in 2005 totaled 17.9 million, ranking fourth in the Nation (University of Florida, 2006); nearly 86 million tourists visited the State (Orlando Business Journal, 2006). In 2005, Florida harvested two-thirds of the total citrus production in the United States and ranked fifth in the Nation net farm income (Florida Department of Agriculture and Consumer Services, 2006). Freshwater is vital for sustaining Florida's population, economy, and agricultural production. Accurate estimates reflecting water use and trends in Florida are compiled in 5-year intervals by the U.S. Geological Survey (USGS) in cooperation with the Florida Department of Environmental Protection (FDEP) and the Northwest Florida, St. Johns River, South Florida, Southwest Florida, and Suwannee River Water Management Districts (Marella, 2004). This coordinated effort provides the necessary data and information for planning future water needs and resource management. The purpose of this fact sheet is to present the highlights of water use in Florida for 2005 along with some significant trends in withdrawals since 1950.

  15. Numerical and experimental investigations of submarine groundwater discharge to a coastal lagoon

    DEFF Research Database (Denmark)

    Haider, Kinza

    The main goal of this study is to understand and estimate the amount of submarine groundwater discharge into Ringkøbing Fjord from shallow and deep aquifer systems at the Eastern shoreline from Ringkøbing catchment in Western Denmark. In order to accomplish this objective, the study was initiated...... of the groundwater discharge occurred near the shoreline of the lagoon, but also off-shore discharge from deep confined aquifers system occurred at places where confining clay layers are eroded by buried valleys. The simulated fresh groundwater discharge was a non-negligible component, 59 % of recharge on the lagoon...... and 6 % of river input into the lagoon. This large-scale study was the motivation to conduct field investigation techniques in order to understand the dynamic processes in the near-shore environment. Field campaigns were conducted every two months in order to understand the seasonal groundwater...

  16. Anthropogenic changes to a billabong in New South Wales. 1. lagoon evolution and phosphorus dynamics

    International Nuclear Information System (INIS)

    Donnelly, T.H.; Ford, P.W.

    1999-01-01

    Anthropogenic changes detected in the sediment of a shallow (∼1.6 m) billabong (Horseshoe Lagoon) are the result of a Sewage Treatment Plant (STP) connection in 1958 and catchment urbanization around 1974. Nutrient-rich water caused the collapse of macrophyte populations, algal blooms became common, and urbanization increased sediment deposition (∼1 cm year -1 ). Changes in P retention were investigated by using dated cores, pore-water element profiles, and water quality records. Two of the cores were examined by analyses of pollen, 137 Cs, elemental analyses by XRF, C and N stable isotope ratio, and organic concentrations. The lagoon is the last of three STP holding ponds. Ponds 1 and 2 were sand-mining pits; they receive no sediment input and have negligible P adsorption. The Fe:P ratios in sediments from three Australian rivers have a common slope and this relationship was used to examine Fe:P ratios in the anoxic bottom sediments of the lagoon. A potential for effluent P adsorption developed in the lagoon through Fe mobilization and enrichment in the upper sediments and a strong clay-Fe-P association. The mean long- term P adsorption in the lagoon (35±) was the result of maintaining clay input to an oxic waterbody. Bacterial sulfate reduction is the main process decreasing available Fe for effluent P adsorption. Appropriately designed systems could expect to maintain effluent P adsorption efficiencies of around 70%. Copyright (1999) CSIRO Publishing

  17. Ground-Water Resources of the Lower Apalachicola-Chattahoochee-Flint River Basin in Parts of Alabama, Florida, and Georgia-Subarea 4 of the Apalachicola-Chattahoochee-Flint and Alabama-Coosa-Tallapoosa River Basins

    National Research Council Canada - National Science Library

    Torak, Lynn J; McDowell, Robin J

    1995-01-01

    .... The Intermediate system consists of the Intracoastal, Chipola, and Jackson Bluff Formations, is limited in areal extent to the southern part of the basin in Florida, and constitutes an aquifer of low yield...

  18. Flow characteristics and salinity patterns of tidal rivers within the northern Ten Thousand Islands, southwest Florida, water years 2007–14

    Science.gov (United States)

    Booth, Amanda C.; Soderqvist, Lars E.

    2016-12-12

    Freshwater flow to the Ten Thousand Islands estuary has been altered by the construction of the Tamiami Trail and the Southern Golden Gate Estates. The Picayune Strand Restoration Project, which is associated with the Comprehensive Everglades Restoration Plan, has been implemented to improve freshwater delivery to the Ten Thousand Islands estuary by removing hundreds of miles of roads, emplacing hundreds of canal plugs, removing exotic vegetation, and constructing three pump stations. Quantifying the tributary flows and salinity patterns prior to, during, and after the restoration is essential to assessing the effectiveness of upstream restoration efforts.Tributary flow and salinity patterns during preliminary restoration efforts and prior to the installation of pump stations were analyzed to provide baseline data and preliminary analysis of changes due to restoration efforts. The study assessed streamflow and salinity data for water years1 2007–2014 for the Faka Union River (canal flow included), East River, Little Wood River, Pumpkin River, and Blackwater River. Salinity data from the Palm River and Faka Union Boundary water-quality stations were also assessed.Faka Union River was the dominant contributor of freshwater during water years 2007–14 to the Ten Thousand Islands estuary, followed by Little Wood and East Rivers. Pumpkin River and Blackwater River were the least substantial contributors of freshwater flow. The lowest annual flow volumes, the highest annual mean salinities, and the highest percentage of salinity values greater than 35 parts per thousand (ppt) occurred in water year 2011 at all sites with available data, corresponding with the lowest annual rainfall during the study. The highest annual flow volumes and the lowest percentage of salinities greater than 35 ppt occurred in water year 2013 for all sites with available data, corresponding with the highest rainfall during the study.In water year 2014, the percentage of monitored annual flow

  19. EPA GOMEX Wild Goose Lagoon 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We compared nekton use of prominent habitat types within a lagoonal system of the northeastern Gulf of Mexico (GoM). These habitat types were defined by combinations...

  20. Transport of radionuclides from the LAMPF lagoons

    International Nuclear Information System (INIS)

    Ferenbaugh, R.W.; Purtymun, W.D.

    1985-01-01

    Monitoring of the discharge water from the Los Alamos Meson Physics Facility lagoons continued during June and December of 1983. The list of radionuclides being monitoring includes 7 Be, 57 Co, 134 Cs, 3 H, 54 Mn, 22 Na, and 83 Rb. The sampling locations and the data obtained to date are presented. Movement of radionuclides around the lagoons has been described in a previous report. 1 reference, 1 table

  1. Environmental perception among residents of Ratones and Peri Lagoon communities, Santa Catarina Island

    Directory of Open Access Journals (Sweden)

    Otávio da Silva Custódio

    2017-06-01

    Full Text Available Lack of basic sanitation is linked to population growth disjointed of public policies. This work developed between July 2015 and July 2016 aimed to evaluate the perceptions of riverside land owners on the status of water bodies in the locations of Ratones River and Peri Lagoon, Florianópolis (Santa Catarina. We interviewed 51 residents in total. And the residents of Ratones knew a larger number of rivers and described direct supply of water bodies to their homes, compared to that obtained in the community of Peri Lagoon, where most homes was supplied by the public network. Both communities have shown intradomiciliary water filtration, assumed riparian forests degraded, considered the rainwater important for ecosystems health, and reported lack of sewage treatment. We conclude that residents tended to have an anthropocentric environmental vision, which residents interpret the environment as a space disconnected from the man.

  2. Assessment of the metals concentration in sediments of Chimaliapan Lagoon, Lerma, Mexico State

    International Nuclear Information System (INIS)

    Perez V, I. A.

    2015-01-01

    The San Pedro Tultepec Lagoon of Quiroga in Lerma, known as Chimaliapan Lagoon is one of the Cienegas of the high course of the Lerma river. Considering that the lagoon is adjacent to an industrial area, have been altered the natural conditions of the channels, degrading the water quality and affecting the systems with different pollution sources, among which are industrial and municipal discharges and runoff of farmland. For this reason was decided to conduct a study in order to assess the concentration of metals in sediments of 4 sites and 4 downloads of the Chimaliapan Lagoon in order to infer the possible natural contributions and/or anthropogenic metals and their impact on both flora and fauna and the population that is supplied with the same, while assessing levels of enrichment of Ti, Cr, Mn, Fe, Cu, Zn and Pb metals as a result of contributions previously mentioned applying the technique of Energy Dispersive X-ray Fluorescence (EDXRF). According to the results by EDXRF, the sediments of the Lagoon assessed with the criterion of the EPA for the disposal of dredged sediments at this site, Mn and Fe only slightly exceed this criterion, then considering the Canadian criteria for the protection of aquatic life OMe, might have slight effects of Cr, Mn, Fe and Cu. Sediment discharges, evaluated with the same criteria indicate that Cr and Pb exceed the limit recommended by the EPA for the disposal of dredged sediments and Cr, Cu and Zn exceed the limit recommended for the protection of aquatic life OMe, noting that these metals may cause slight effects on organisms living in the Lagoon, such as carp and other organisms that live there, causing potential effects on humans through the food chain. (Author)

  3. Curonian Lagoon drainage basin modelling and assessment of climate change impact

    Directory of Open Access Journals (Sweden)

    Natalja Čerkasova

    2016-04-01

    Full Text Available The Curonian Lagoon, which is the largest European coastal lagoon with a surface area of 1578 km2 and a drainage area of 100,458 km2, is facing a severe eutrophication problem. With its increasing water management difficulties, the need for a sophisticated hydrological model of the Curonian Lagoon's drainage area arose, in order to assess possible changes resulting from local and global processes. In this study, we developed and calibrated a sophisticated hydrological model with the required accuracy, as an initial step for the future development of a modelling framework that aims to correctly predict the movement of pesticides, sediments or nutrients, and to evaluate water-management practices. The Soil and Water Assessment Tool was used to implement a model of the study area and to assess the impact of climate-change scenarios on the run-off of the Nemunas River and the Minija River, which are located in the Curonian Lagoons drainage basin. The models calibration and validation were performed using monthly streamflow data, and evaluated using the coefficient of determination (R2 and the Nash-Sutcliffe model efficiency coefficient (NSE. The calculated values of the R2 and NSE for the Nemunas and Minija Rivers stations were 0.81 and 0.79 for the calibration, and 0.679 and 0.602 for the validation period. Two potential climate-change scenarios were developed within the general patterns of near-term climate projections, as defined by the Intergovernmental Panel on Climate Change Fifth Assessment Report: both pessimistic (substantial changes in precipitation and temperature and optimistic (insubstantial changes in precipitation and temperature. Both simulations produce similar general patterns in river-discharge change: a strong increase (up to 22% in the winter months, especially in February, a decrease during the spring (up to 10% and summer (up to 18%, and a slight increase during the autumn (up to 10%.

  4. Variability of thermohaline properties in Pearl Lagoon, Nicaragua (ESP

    Directory of Open Access Journals (Sweden)

    Carlos L. Brenes

    2016-03-01

    Full Text Available Several hydrographic surveys were carried out in Pearl Lagoon, Nicaragua between april 1995 and december 1997 under the DIPAL (Proyecto para el Desarrollo Integral de la Pesca Artesanal en la Región Autónoma del Atlántico Sur project. Surface temperature, salinity, dissolved oxygen and turbidity have been measured in 88 hydrographic campaigns. The annual cycle shows maximum and minimum temperatures in May (29.4 °C and December (25.6 °C respectively, maximum salinity (25.6 °C in April, one month before the thermal peak, and minimum salinities (2‰ between July and August, when the annual precipitation index attains its seasonal maximum in the study area. In the case of dissolved O2 the maximum values of oxygen saturation were observed between March and May (90%, when the water turbidity in the lagoon is at its lowest and freshwater contributions from the rivers attains its minimum value. During the rainy season, in the second half of the year, there is an important decrease in oxygen contents, mainly as a consequence of the degradation of organic matter of riverine origin.

  5. Hair Mercury Concentrations and Fish Consumption Patterns in Florida Residents

    Directory of Open Access Journals (Sweden)

    Adam M. Schaefer

    2014-06-01

    Full Text Available Mercury exposure through the consumption of fish and shellfish represents a significant public health concern in the United States. Recent research has demonstrated higher seafood consumption and subsequent increased risk of methylmercury exposure among subpopulations living in coastal areas. The identification of high concentrations of total mercury in blood and skin among resident Atlantic bottlenose dolphins (Tursiops truncatus in the Indian River Lagoon (IRL, a coastal estuary in Florida, alerted us to a potential public health hazard in the contiguous human population. Therefore, we analyzed hair mercury concentrations of residents living along the IRL and ascertained their sources and patterns of seafood consumption. The total mean mercury concentration for 135 residents was 1.53 ± 1.89 µg/g. The concentration of hair mercury among males (2.02 ± 2.38 µg/g was significantly higher than that for females (0.96 ± 0.74 µg/g (p < 0.01. Log transformed hair mercury concentration was significantly associated with the frequency of total seafood consumption (p < 0.01. Individuals who reported consuming seafood once a day or more were 3.71 (95% CI 0.84–16.38 times more likely to have a total hair mercury concentration over 1.0 µg/g, which corresponds approximately to the U.S. EPA reference dose, compared to those who consumed seafood once a week or less. Hair mercury concentration was also significantly higher among individuals who obtained all or most of their seafood from local recreational sources (p < 0.01. The elevated human mercury concentrations mirror the elevated concentrations observed in resident dolphins in the same geographical region. The current study is one of the first to apply the concept of a sentinel animal to a contiguous human population.

  6. Aghien lagoon: a sustainable resource of fresh water for the city of Abidjan (Ivory Coast)? Description of the project and preliminary results

    Science.gov (United States)

    Kamagaté, Bamory; Effebi, Rose K.; Goula Bi, Tié Albert; Lanciné Goné, Droh; Noufé, Djibril; Diallo, Seydou; Ehouman, Serge K.; Koffi, Thierry; Zamblé Trabi, Armand; Lazare, Kouakou; Paturel, Jean Emmanuel; Perrin, Jean-Louis; Salles, Christian; Seguis, Luc; Tournoud, Marie-George; Karoui, Hela

    2016-04-01

    With more than 6 million inhabitants, Abidjan district faces tremendous difficulties in water supply. The aquifer of the Continental Terminal which is actually the only drinking water source of the city shows a decline of resources and water demand is increasing due to the population growth. Moreover significant evidences of chemical and biological pollution of the groundwater are observed The Aghien lagoon, the largest freshwater pool located near Abidjan, has been identified by the State of Côte d'Ivoire as a potential resource for the production of drinking water.. The main objective of this project is to assess the quantitative and qualitative capacity of the Aghien lagoon to complement the water supply of Abidjan city in the near future. The main components of the project are: • to assess the water budget of the lagoon and its tributaries, • to characterize the spatial and temporal variability of contaminant levels and fluxes from the tributaries toward the lagoon, • to assess the sustainability of the water resources (quantity and quality) of the lagoon according to land use changes in the catchments . The project started in January 2015. The first year was devoted to the set-up of hydro-meteorological gauges within the lagoon watershed. Three major tributaries of the lagoon are considered, the Mé (4000 km2), the Djibi (78 km2) and Bete (206 km2) rivers. Since the start of the project, bi-monthly hydrochemical sampling surveys have been carried out along the tributaries and in the lagoon. The data available from the surveys concern the physico-chemical parameters, trace elements, all the forms of nitrogen and phosphorus, organic carbon, suspended solids. The Djibi and Bete watersheds are partly urbanized while the Mé basin is mainly rural. Baseflow has been identified as the major contribution to streamflow at the annual scale. The Mé flows into a channel downstream to the Aghien lagoon but during the floods, water from the Mé River can flow up the

  7. Sedimentation rate and lateral migration of tidal channels in the Lagoon of Venice (Northern Italy)

    Science.gov (United States)

    Donnici, Sandra; Madricardo, Fantina; Serandrei-Barbero, Rossana

    2017-11-01

    Tidal channels are crucial for the functioning of highly valuable coastal environments, such as estuaries and lagoons. Their properties, however, are currently less understood than those of river systems. To elucidate their past behaviour, an extensive geophysical investigation was performed to reconstruct the evolution of channels and tidal surfaces in the central part of the Lagoon of Venice (Italy) over the past 5000 years. Comparing high-spatial-resolution acoustic data and sedimentary facies analyses of 41 cores, 29 of which were radiocarbon dated, revealed the sedimentation rates in different lagoonal environments and allowed the migration of two large meanders to be reconstructed. The average sedimentation rate of the study succession in the different sedimentary environments was 1.27 mm yr-1. The lateral migration rates were 13-23 m/century. This estimate is consistent with the lateral migration rates determined by comparing aerial photographs of recent channels. Comparing the buried channels with historical and current maps showed that, in general, the number of active channels is now reduced. Their morphology was sometimes simplified by artificial interventions. An understanding of the impact of the artificial interventions over time is useful for the management and conservation of tidal environments, particularly for the Lagoon of Venice, where management authorities are currently debating the possible deepening and rectification of large navigation channels.

  8. Trend of Heavy Metal Concentrations in Lagos Lagoon Ecosystem

    African Journals Online (AJOL)

    komla

    The distribution and occurrence of heavy metals in the sediment, water and benthic animals of the Lagos lagoon ... The concentrations of the metals detected in the lagoon sediment and water ..... waste products contaminating water sources.

  9. Ground-Water Resources of the Lower Apalachicola-Chattahoochee-Flint River Basin in Parts of Alabama, Florida, and Georgia-Subarea 4 of the Apalachicola-Chattahoochee-Flint and Alabama-Coosa-Tallapoosa River Basins

    Science.gov (United States)

    1995-01-01

    Counties, Ga . Evaluation of ground- water-development potential in the virtually untapped Intermediate system has questionable reliability due to the...Alabama, Florida, and Georgia into 4 districts: Fall Line Hills, Dougherty Plain, Tifton Upland, and Gulf Coastal Lowlands. Physiographic descriptions...approximately with the boundary between the Tifton Uplands and the Dough- erty Plain districts and the Gulf Coastal Lowlands district occupies the

  10. Groundwater-flow budget for the lower Apalachicola-Chattahoochee-Flint River Basin in southwestern Georgia and parts of Florida and Alabama, 2008–12

    Science.gov (United States)

    Jones, L. Elliott; Painter, Jaime A.; LaFontaine, Jacob H.; Sepúlveda, Nicasio; Sifuentes, Dorothy F.

    2017-12-29

    As part of the National Water Census program in the Apalachicola-Chattahoochee-Flint (ACF) River Basin, the U.S. Geological Survey evaluated the groundwater budget of the lower ACF, with particular emphasis on recharge, characterizing the spatial and temporal relation between surface water and groundwater, and groundwater pumping. To evaluate the hydrologic budget of the lower ACF River Basin, a groundwater-flow model, constructed using MODFLOW-2005, was developed for the Upper Floridan aquifer and overlying semiconfining unit for 2008–12. Model input included temporally and spatially variable specified recharge, estimated using a Precipitation-Runoff Modeling System (PRMS) model for the ACF River Basin, and pumping, partly estimated on the basis of measured agricultural pumping rates in Georgia. The model was calibrated to measured groundwater levels and base flows, which were estimated using hydrograph separation.The simulated groundwater-flow budget resulted in a small net cumulative loss of groundwater in storage during the study period. The model simulated a net loss in groundwater storage for all the subbasins as conditions became substantially drier from the beginning to the end of the study period. The model is limited by its conceptualization, the data used to represent and calibrate the model, and the mathematical representation of the system; therefore, any interpretations should be considered in light of these limitations. In spite of these limitations, the model provides insight regarding water availability in the lower ACF River Basin.

  11. A study of sediment transport in the Herbert River, Australia, using plutonium AMS

    International Nuclear Information System (INIS)

    Everett, S.E.; Tims, S.G.; Fifield, L.K.; Hancock, G.J.

    2005-01-01

    The ANU and CSIRO have begun a new collaboration to study the human impacts of sediment transport into the Great Barrier Reef (GBR) lagoon. The project aims to use fallout plutonium for essentially the first time, as an isotopic tracer of soil and sediment movement. The study aims to assess how recent human activity in the river catchments that feed the GBR lagoon is influencing the distribution and quantity of sediment entering the lagoon. 2 figs

  12. Dynamic behaviour of lagoon ecosystems

    International Nuclear Information System (INIS)

    Cioffi, F.

    2008-01-01

    The dynamic behaviour of primary producers in coastal lagoons due to change of external control parameters, phosphorous external load and maximum tidal flow rate, is investigated by using a eutrophication model. The eutrophication model allows the simulation of the temporal evolution of the concentration of the following species: a) in the water column: dissolved oxygen, vegetal organic carbon, particulate and dissolved organic carbon, dissolved phosphorous and hydrogen sulphide; b) in sediments: dissolved oxygen, particulate and dissolved organic carbon, dissolved and adsorbed phosphorous, hydrogen sulphide. The vegetal organic carbon is distinguished in three components related to the main groups of primary producers, namely eel grass, macro algae and microalgae, having different modalities of nutrient uptake and kinetics parameters depending on the S/V ratio. Diagrams representing the ecosystems dynamic response to the changes of the control parameters were constructed by simulations. The response diagrams suggest the existence of regime shifts which border different ecosystem stability ranges, characterized by the dominance of a specific group of primary producers and by different ecosystem vulnerability at summer water anoxia. A catastrophic bifurcation or abrupt regime shift, evidenced by Poincare sections obtained mapping, at a prefixed time period, the values of the concentration of the species, occurs for a critical value of the control parameter and manifests itself as an abrupt change of the dominant species from eel grass to macro algae. An analogous abrupt change from eel grass to macro algae occurs for a critical value of the tidal flowrate assumed as control parameter in simulations conducted for an assigned value of external phosphorous load.

  13. DISTRIBUSI HUTAN BAKAU DI LAGUNA PANTAI SELATAN YOGYAKARTA (Mangrove Distribution at the Lagoons in the Southern Coast of Yogyakarta

    Directory of Open Access Journals (Sweden)

    Tjut Sugandawaty Djohan

    2007-03-01

    Full Text Available ABSTRAK  Kehadiran sisa hutan bakau di laguna Bogowonto, pantai selatan Yogyakarta menunjukkan bahwa pada masa lalu laguna tersebut didominasi oleh hutan bakau, sehingga penelitian ini bertujuan mempelajari kehadiran vegetasi bakau di laguna-laguna dan muara sungai di pantai selatan tersebut. Ada empat laguna di pantai Selatan Yogyakarta, laguna Bogowonto, Serang, Progo, Opak, dan satu muara sungai, Kali Baron. Laguna tersebut merupakan laguna internitten, artinya pada musim kemarau, mulut sungainya tertutup gumuk pasir dan laguna didominasi oleh perairan tawar dan merupakan ekosistem tergenang. Sebaliknya di musim hujan mulut sungai terbuka, laguna bersifat sebagai ekosistem pasang surut. Data vegetasi dicuplik dengan menggunakan kuadrat plot berukuran 10m x 20m dengan ulangan dua kali. Kuadrat plot ditempatkan pada pusat distribusi mangrovenya, yang dipilih mulai dari rawa burit ke arah muara sungai. Tekstur tanah, hara tanah, salinitas air dan hara air juga dikaji. Kehadiran hutan bakau di laguna dibatasi oleh tekstur tanah. Tekstur pasir, 60-99 %, mendominasi laguna Serang, Progo, Opak dan muara kali Baron. Komunitas bakau hanya ditemukan di laguna Bogowonto, yang tersusun atas 5 jenis bakau, Sonneratia alba, Nypa fruticans, Acanthus ilicifolius, Acrosticum sp., dan Derris heterophylla, dan dua jenis spesies peralihan, Pandanus sp. dan Cynodon dactylon. Pola distribusi komunitasnya mengelompok (clump, mempunyai tipe riverine mangrove,dan tidak membentuk zonasi. Sonneratia hadir mulai dari muara sungai sampai di rawa burit. Ketika air surut salinitas berkisar antara 0-6,5 %. Nypa hanya ditemukan satu kelompok di kaki gumuk. Distribusi Sonneratia tidak ditentukan oleh tinggi genangan, akan tetapi tinggi pneumatophor mengikuti pola tinggi genangan air. Di laguna Bogowonto, spesies bakau tidak mempunyai zonasi dan beradaptasi pada sistem ekologinya.   ABSTRACT  The presence of mangrove remnant at the lagoon of Bogowonto River in the southern

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

    Science.gov (United States)

    Aké-Castillo, José A.; Vázquez, Gabriela

    2008-07-01

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

  15. Effects of organic pollution and physical stress on benthic macroinvertebrate communities from two intermittently closed and open coastal lagoons (ICOLLs)

    Science.gov (United States)

    Coelho, Susana; Pérez-Ruzafa, Angel; Gamito, Sofia

    2015-12-01

    Benthic macroinvertebrate communities and environmental conditions were studied in two intermittently closed and open coastal lakes and lagoons (ICOLLs), located in southern Algarve (Foz do Almargem e Salgados), with the purpose of evaluating the effects of organic pollution, originated mainly from wastewater discharges, and the physical stress caused by the irregular opening of the lagoons. Most of the year, lagoons were isolated from the sea, receiving the freshwater inputs from small rivers and in Salgados, also from the effluents of a wastewater plant. According to environmental and biotic conditions, Foz do Almargem presented a greater marine influence and a lower trophic state (mesotrophic) than Salgados (hypereutrophic). Benthic macroinvertebrate communities in the lagoons were distinct, just as their relations with environmental parameters. Mollusca were the most abundant macroinvertebrates in Foz do Almargem, while Insecta, Oligochaeta and Crustacea were more relevant in Salgados. Corophium multisetosum occurred exclusively in Salgados stations and, just as Chironomus sp., other Insecta and Oligochaeta, densities were positively related to total phosphorus, clay content and chlorophyll a concentration in the sediment, chlorophyll a concentration in water and with total dissolved inorganic nitrogen. Abra segmentum, Cerastoderma glaucum, Peringia ulvae and Ecrobia ventrosa occurred only in Foz do Almargem, with lower values of the above mentioned parameters. Both lagoons were dominated by deposit feeders and taxa tolerant to environmental stress, although in Salgados there was a greater occurrence of opportunistic taxa associated to pronounced unbalanced situations, due to excess organic matter enrichment.

  16. Diuron tolerance and potential degradation by pelagic microbiomes in the Great Barrier Reef lagoon

    Directory of Open Access Journals (Sweden)

    Florent E. Angly

    2016-03-01

    Full Text Available Diuron is a herbicide commonly used in agricultural areas where excess application causes it to leach into rivers, reach sensitive marine environments like the Great Barrier Reef (GBR lagoon and pose risks to marine life. To investigate the impact of diuron on whole prokaryotic communities that underpin the marine food web and are integral to coral reef health, GBR lagoon water was incubated with diuron at environmentally-relevant concentration (8 µg/L, and sequenced at specific time points over the following year. 16S rRNA gene amplicon profiling revealed no significant short- or long-term effect of diuron on microbiome structure. The relative abundance of prokaryotic phototrophs was not significantly altered by diuron, which suggests that they were largely tolerant at this concentration. Assembly of a metagenome derived from waters sampled at a similar location in the GBR lagoon did not reveal the presence of mutations in the cyanobacterial photosystem that could explain diuron tolerance. However, resident phages displayed several variants of this gene and could potentially play a role in tolerance acquisition. Slow biodegradation of diuron was reported in the incubation flasks, but no correlation with the relative abundance of heterotrophs was evident. Analysis of metagenomic reads supports the hypothesis that previously uncharacterized hydrolases carried by low-abundance species may mediate herbicide degradation in the GBR lagoon. Overall, this study offers evidence that pelagic phototrophs of the GBR lagoon may be more tolerant of diuron than other tropical organisms, and that heterotrophs in the microbial seed bank may have the potential to degrade diuron and alleviate local anthropogenic stresses to inshore GBR ecosystems.

  17. Diuron tolerance and potential degradation by pelagic microbiomes in the Great Barrier Reef lagoon

    Science.gov (United States)

    Pantos, Olga; Morgan, Thomas C.; Rich, Virginia; Tonin, Hemerson; Bourne, David G.; Mercurio, Philip; Negri, Andrew P.; Tyson, Gene W.

    2016-01-01

    Diuron is a herbicide commonly used in agricultural areas where excess application causes it to leach into rivers, reach sensitive marine environments like the Great Barrier Reef (GBR) lagoon and pose risks to marine life. To investigate the impact of diuron on whole prokaryotic communities that underpin the marine food web and are integral to coral reef health, GBR lagoon water was incubated with diuron at environmentally-relevant concentration (8 µg/L), and sequenced at specific time points over the following year. 16S rRNA gene amplicon profiling revealed no significant short- or long-term effect of diuron on microbiome structure. The relative abundance of prokaryotic phototrophs was not significantly altered by diuron, which suggests that they were largely tolerant at this concentration. Assembly of a metagenome derived from waters sampled at a similar location in the GBR lagoon did not reveal the presence of mutations in the cyanobacterial photosystem that could explain diuron tolerance. However, resident phages displayed several variants of this gene and could potentially play a role in tolerance acquisition. Slow biodegradation of diuron was reported in the incubation flasks, but no correlation with the relative abundance of heterotrophs was evident. Analysis of metagenomic reads supports the hypothesis that previously uncharacterized hydrolases carried by low-abundance species may mediate herbicide degradation in the GBR lagoon. Overall, this study offers evidence that pelagic phototrophs of the GBR lagoon may be more tolerant of diuron than other tropical organisms, and that heterotrophs in the microbial seed bank may have the potential to degrade diuron and alleviate local anthropogenic stresses to inshore GBR ecosystems. PMID:26989611

  18. Diuron tolerance and potential degradation by pelagic microbiomes in the Great Barrier Reef lagoon.

    Science.gov (United States)

    Angly, Florent E; Pantos, Olga; Morgan, Thomas C; Rich, Virginia; Tonin, Hemerson; Bourne, David G; Mercurio, Philip; Negri, Andrew P; Tyson, Gene W

    2016-01-01

    Diuron is a herbicide commonly used in agricultural areas where excess application causes it to leach into rivers, reach sensitive marine environments like the Great Barrier Reef (GBR) lagoon and pose risks to marine life. To investigate the impact of diuron on whole prokaryotic communities that underpin the marine food web and are integral to coral reef health, GBR lagoon water was incubated with diuron at environmentally-relevant concentration (8 µg/L), and sequenced at specific time points over the following year. 16S rRNA gene amplicon profiling revealed no significant short- or long-term effect of diuron on microbiome structure. The relative abundance of prokaryotic phototrophs was not significantly altered by diuron, which suggests that they were largely tolerant at this concentration. Assembly of a metagenome derived from waters sampled at a similar location in the GBR lagoon did not reveal the presence of mutations in the cyanobacterial photosystem that could explain diuron tolerance. However, resident phages displayed several variants of this gene and could potentially play a role in tolerance acquisition. Slow biodegradation of diuron was reported in the incubation flasks, but no correlation with the relative abundance of heterotrophs was evident. Analysis of metagenomic reads supports the hypothesis that previously uncharacterized hydrolases carried by low-abundance species may mediate herbicide degradation in the GBR lagoon. Overall, this study offers evidence that pelagic phototrophs of the GBR lagoon may be more tolerant of diuron than other tropical organisms, and that heterotrophs in the microbial seed bank may have the potential to degrade diuron and alleviate local anthropogenic stresses to inshore GBR ecosystems.

  19. Tracing organic matter sources in a tropical lagoon of the Caribbean Sea

    Science.gov (United States)

    Alonso-Hernández, Carlos M.; Garcia-Moya, Alejandro; Tolosa, Imma; Diaz-Asencio, Misael; Corcho-Alvarado, Jose Antonio; Morera-Gomez, Yasser; Fanelli, Emanuela

    2017-09-01

    The natural protected lagoon of Guanaroca, located between Cienfuegos Bay and the Arimao River, Cuba, has been heavily impacted by human-induced environmental changes over the past century. Sources of organic matter in the Guanaroca lagoon and concentrations of radioisotopes (210Pb, 226Ra, 137Cs and 239,240Pu), as tracers of anthropogenic impacts, were investigated in a 78 cm sediment core. Variations in total organic carbon (TOC), total nitrogen (TN), stable isotopic composition (δ13C and δ15N) and ratio of total organic carbon to total nitrogen (C/N) were analysed. On such a basis, environmental changes in the lagoon were revealed. Down core variation patterns of the parameters representing sources of organic matter were predominantly related to the impacts of human activities. Up to the nineteenth century, the principal sources of organic matter to sediments (more than 80%) were a mixing of terrestrial vascular plants ( 48%) and freshwater phytoplankton ( 8%), with minimal contribution from the marine component ( 16%). In the period 1900-1980, due to the strong influence of human activities in the catchment area, the water exchange capacity of the lagoon declined substantially, as indicated by the relatively high proportion of organic matter originated from human activities (58%). Since 1980, as a result of management actions in the protected area, the lagoon has regained gradually its capability to exchange freshwater, showing sources of organic matter similar to the natural conditions recorded previous to 1900, although an indication of human impact (treated sewage contributed for 26% to the organic matter in sediments) was still observed and further management measures would be required.

  20. 78 FR 17087 - Special Local Regulation; New River Raft Race, New River; Fort Lauderdale, FL

    Science.gov (United States)

    2013-03-20

    ...-AA08 Special Local Regulation; New River Raft Race, New River; Fort Lauderdale, FL AGENCY: Coast Guard... on the New River in Fort Lauderdale, Florida during the Rotary Club of Fort Lauderdale New River Raft... States during the Rotary Club of Fort Lauderdale New River Raft Race. On March 23, 2013, Fort Lauderdale...

  1. Seagrass community dynamics in a subtropical estuarine lagoon

    Energy Technology Data Exchange (ETDEWEB)

    Thorhaug, A.; Roessler, M.A.

    1977-11-01

    The temporal and spatial distributions of major plant and animal species were investigated for 4 years in south Biscayne Bay including Card Sound, Florida, a subtropical estuarine lagoon. This was part of a larger study including chemical, physical and geological investigations. The major species of plants were Thalassia testudinum Banks ex Konig, turtle grass, Laurencia poitei (Lamour.) Howe, a red macroalga and the green algae Penicillus capitatus Lamarck and Halimeda incrassata (Ellis) Lamour. Standing crop and production of plant material taken bi-weekly is given in detail for 16 stations in Card Sound for the 4-year period and for eight stations in Biscayne Bay for a 1-year period. The major animal species were not equally distributed; in the near-shore Thalassia community, species of Pagurus, Neopanope, Hippolyte, Cerithium, Bulla, Prunum and Modulus were dominant. In mid-bay, where patchy Thalassia plus green algae occurred, Thor and Chondrilla were the dominant animals. Near the fringing islands, where tidal flow caused more oceanic conditions, the community was dominated by sponges, urchins and corals. This highlights the structural differences in what is now termed the ''Thalassia community.'' Comparisons with other known Thalassia communities are made.

  2. Participation and Sustainable Management of Coastal Lagoon Ecosystems: The Case of the Fosu Lagoon in Ghana

    Directory of Open Access Journals (Sweden)

    Ernest K.A. Afrifa

    2010-01-01

    Full Text Available Participation as a tool has been applied as a social learning process and communication platform to create awareness among stakeholders in the context of resource utilisation. The application of participatory processes to aquatic ecosystem management is attracting a growing body of literature. However, the application of participation as a tool for sustainable management of coastal lagoon ecosystems is recent. This paper examines the context and the extent of participation of stakeholders in the management of the Fosu lagoon in Ghana. Six hundred individuals from twenty seven stakeholder groups were randomly selected for study. Both closed and open-ended questions were used in face-to-face interviews with stakeholders. The findings indicate that the stakeholder groups were not involved in decision-making regarding the conservation of the lagoon irrespective of their expertise in planning and/or their interest in lagoon resource utilisation. This situation has created apathy among some of the stakeholders who feel neglected in the decision-making process. There is scope for broadening the base of interest groups in decision-making processes regarding the lagoon and improving stakeholder participation in the management of the lagoon to ensure the sustainability of the management process.

  3. Assessment of the Trophic State of Saquarema Lagoonal System, Rio de Janeiro (Brazil

    Directory of Open Access Journals (Sweden)

    Pierre Philippe Belart Brandão Dias

    2017-08-01

    Full Text Available This work intends to apply new ecological descriptors to a coastal marine area aiming to assess its environmental trophic status. This approach makes possible to identify relevant variables associated with eutrophication process applicable and valid worldwide. The aim of this work is to study the organic matter (OM quality and quantity, in terms of biopolymers, in Saquarema Lagoonal System (SLS located in Rio de Janeiro State (Brazil. Sediment samples collected in SLS were analyzed in this study for granulometric and geochemical data such as total organic carbon (TOC, total sulfur (TS and biopolimeric carbon (BPC concentrations, including proteins (PTN, carbohydrates (CHO and lipids (LIP. These data were combined with additional environmental parameters measured in water of the four linked lagoons that compose SLS. Data analyses allowed the identification of four distinct regions in SLS: an inner and impacted zone characterized by sediment particularly enriched in TOC, with lowest quality of OM most probably provided by contaminated effluents and rivers runoff; an outer-less impacted lagoonal area with relatively low TOC content and submitted to high hydrodynamic forces; an intermediate area characterized by transitional features between the two previously mentioned and a zone that is influenced mainly by salinity. The organic matter accumulation depends on the hydrodynamic conditions mostly governed by tidal currents. The quality of organic matter seems to be mainly influenced by the water renewal, rivers inputs and mangroves contributions as well as by the autochthonous lagoonal biological productivity. Results of this work indicate that the inner zone of SLS is being affected by eutrophication not necessarily caused by anthropic factors.

  4. Hydrologic and water-quality conditions in the lower Apalachicola-Chattahoochee-Flint and parts of the Aucilla-Suwannee-Ochlockonee River basins in Georgia and adjacent parts of Florida and Alabama during drought conditions, July 2011

    Science.gov (United States)

    Gordon, Debbie W.; Peck, Michael F.; Painter, Jaime A.

    2012-01-01

    As part of the U.S. Department of the Interior sustainable water strategy, WaterSMART, the U.S. Geological Survey documented hydrologic and water-quality conditions in the lower Apalachicola-Chattahoochee-Flint and western and central Aucilla-Suwannee-Ochlockonee River basins in Alabama, Florida, and Georgia during low-flow conditions in July 2011. Moderate-drought conditions prevailed in this area during early 2011 and worsened to exceptional by June, with cumulative rainfall departures from the 1981-2010 climate normals registering deficits ranging from 17 to 27 inches. As a result, groundwater levels and stream discharges measured below median daily levels throughout most of 2011. Water-quality field properties including temperature, dissolved oxygen, specific conductance, and pH were measured at selected surface-water sites. Record-low groundwater levels measured in 12 of 43 surficial aquifer wells and 128 of 312 Upper Floridan aquifer wells during July 2011 underscored the severity of drought conditions in the study area. Most wells recorded groundwater levels below the median daily statistic, and 7 surficial aquifer wells were dry. Groundwater-level measurements taken in July 2011 were used to determine the potentiometric surface of the Upper Floridan aquifer. Groundwater generally flows to the south and toward streams except in reaches where streams discharge to the aquifer. The degree of connection between the Upper Floridan aquifer and streams decreases east of the Flint River where thick overburden hydraulically separates the aquifer from stream interaction. Hydraulic separation of the Upper Floridan aquifer from streams located east of the Flint River is shown by stream-stage altitudes that differ from groundwater levels measured in close proximity to streams. Most streams located in the study area during 2011 exhibited below normal flows (streamflows less than the 25th percentile), substantiating the severity of drought conditions that year. Streamflow

  5. Mercury in the sediments of the Marano and Grado Lagoon (northern Adriatic Sea): Sources, distribution and speciation

    Science.gov (United States)

    Acquavita, Alessandro; Covelli, Stefano; Emili, Andrea; Berto, Daniela; Faganeli, Jadran; Giani, Michele; Horvat, Milena; Koron, Neža; Rampazzo, Federico

    2012-11-01

    The existence of mining tailings in Idrija (Slovenia) and their subsequent transportation via the Isonzo River has been the primary source of mercury (Hg) in the northern Adriatic Sea for almost 500 years, making the Gulf of Trieste and the adjacent Marano and Grado Lagoon two of the most contaminated marine areas in the world. A further, more recent, contribution of Hg has been added by the operation of a chlor-alkali plant (CAP) located in the drainage basin flowing into the Lagoon. On the basis of previous research, as well as new data obtained from the "MIRACLE" project (Mercury Interdisciplinary Research for Appropriate Clam farming in a Lagoon Environment), the spatial distribution of Hg and its relationships with methylmercury (MeHg), organic matter and several geochemical parameters in surface sediments were investigated. The predominant and long-term impacts of the cinnabar-rich Isonzo River particulate matter in the Lagoon surface sediments are evident and confirmed by a decreasing concentration gradient from east (>11 μg g-1) to west (0.7 μg g-1). Hg originated from the CAP is only significant in the central sector of the Lagoon. Hg is primarily associated with fine-grained sediments (constitutes, on average, 0.08% of total Hg and percentages are comparable to those obtained in similar lagoon environments. Higher MeHg concentrations in low to intermediate Hg-contaminated sediments indicate that the metal availability is not a limiting factor for MeHg occurrence, thus suggesting a major role played by environmental conditions and/or speciation. The reasonably good correlation between MeHg normalized to humic acid (HA) content and humic δ13C indicates that MeHg is preferentially associated with autochthonous δ13C-enriched HAs in lagoon surface sediments, suggesting that the structure of "marine" HAs, less refractory and less aromatic, could favor MeHg binding and/or production. In the context of the potential hazard of Hg and MeHg accumulation in

  6. Application of the Support Vector Regression Method for Turbidity Assessment with MODIS on a Shallow Coral Reef Lagoon (Voh-Koné-Pouembout, New Caledonia

    Directory of Open Access Journals (Sweden)

    Guillaume Wattelez

    2017-09-01

    Full Text Available Particle transport by erosion from ultramafic lands in pristine tropical lagoons is a crucial problem, especially for the benthic and pelagic biodiversity associated with coral reefs. Satellite imagery is useful for assessing particle transport from land to sea. However, in the oligotrophic and shallow waters of tropical lagoons, the bottom reflection of downwelling light usually hampers the use of classical optical algorithms. In order to address this issue, a Support Vector Regression (SVR model was developed and tested. The proposed application concerns the lagoon of New Caledonia—the second longest continuous coral reef in the world—which is frequently exposed to river plumes from ultramafic watersheds. The SVR model is based on a large training sample of in-situ turbidity values representative of the annual variability in the Voh-Koné-Pouembout lagoon (Western Coast of New Caledonia during the 2014–2015 period and on coincident satellite reflectance values from MODerate Resolution Imaging Spectroradiometer (MODIS. It was trained with reflectance and two other explanatory parameters—bathymetry and bottom colour. This approach significantly improved the model’s capacity for retrieving the in-situ turbidity range from MODIS images, as compared with algorithms dedicated to deep oligotrophic or turbid waters, which were shown to be inadequate. This SVR model is applicable to the whole shallow lagoon waters from the Western Coast of New Caledonia and it is now ready to be tested over other oligotrophic shallow lagoon waters worldwide.

  7. Biological, chemical and other data collected from station Indian River Lagoon - Link Port (IRL-LP) by Florida Atlantic University and assembled by Southeast Coastal Ocean Observing Regional Association (SECOORA) in the Coastal Waters of Florida from 2015-10-07 to 2017-06-24 (NCEI Accession 0163764)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0163764 contains oceanographic and surface meteorological data in netCDF formatted files, which follow the Climate and Forecast metadata convention...

  8. Coastal Evolution in a Mediterranean Microtidal Zone: Mid to Late Holocene Natural Dynamics and Human Management of the Castelló Lagoon, NE Spain.

    Science.gov (United States)

    Ejarque, Ana; Julià, Ramon; Reed, Jane M; Mesquita-Joanes, Francesc; Marco-Barba, Javier; Riera, Santiago

    2016-01-01

    We present a palaeoenvironmental study of the Castelló lagoon (NE Spain), an important archive for understanding long-term interactions between dynamic littoral ecosystems and human management. Combining geochemistry, mineralogy, ostracods, diatoms, pollen, non-pollen palynomorphs, charcoal and archaeo-historical datasets we reconstruct: 1) the transition of the lagoon from a marine to a marginal environment between ~3150 cal BC to the 17th century AD; 2) fluctuations in salinity; and 3) natural and anthropogenic forces contributing to these changes. From the Late Neolithic to the Medieval period the lagoon ecosystem was driven by changing marine influence and the land was mainly exploited for grazing, with little evidence for impact on the natural woodland. Land-use exploitation adapted to natural coastal dynamics, with maximum marine flooding hampering agropastoral activities between ~1550 and ~150 cal BC. In contrast, societies actively controlled the lagoon dynamics and become a major agent of landscape transformation after the Medieval period. The removal of littoral woodlands after the 8th century was followed by the expansion of agrarian and industrial activities. Regional mining and smelting activities polluted the lagoon with heavy metals from the ~11th century onwards. The expansion of the milling industry and of agricultural lands led to the channelization of the river Muga into the lagoon after ~1250 cal AD. This caused its transformation into a freshwater lake, increased nutrient load, and the infilling and drainage of a great part of the lagoon. By tracking the shift towards an anthropogenically-controlled system around ~750 yr ago, this study points out Mediterranean lagoons as ancient and heavily-modified systems, with anthropogenic impacts and controls covering multi-centennial and even millennial timescales. Finally, we contributed to the future construction of reliable seashell-based chronologies in NE Spain by calibrating the Banyuls-sur-Mer

  9. Coastal Evolution in a Mediterranean Microtidal Zone: Mid to Late Holocene Natural Dynamics and Human Management of the Castello Lagoon, NE Spain.

    Directory of Open Access Journals (Sweden)

    Ana Ejarque

    Full Text Available We present a palaeoenvironmental study of the Castelló lagoon (NE Spain, an important archive for understanding long-term interactions between dynamic littoral ecosystems and human management. Combining geochemistry, mineralogy, ostracods, diatoms, pollen, non-pollen palynomorphs, charcoal and archaeo-historical datasets we reconstruct: 1 the transition of the lagoon from a marine to a marginal environment between ~3150 cal BC to the 17th century AD; 2 fluctuations in salinity; and 3 natural and anthropogenic forces contributing to these changes. From the Late Neolithic to the Medieval period the lagoon ecosystem was driven by changing marine influence and the land was mainly exploited for grazing, with little evidence for impact on the natural woodland. Land-use exploitation adapted to natural coastal dynamics, with maximum marine flooding hampering agropastoral activities between ~1550 and ~150 cal BC. In contrast, societies actively controlled the lagoon dynamics and become a major agent of landscape transformation after the Medieval period. The removal of littoral woodlands after the 8th century was followed by the expansion of agrarian and industrial activities. Regional mining and smelting activities polluted the lagoon with heavy metals from the ~11th century onwards. The expansion of the milling industry and of agricultural lands led to the channelization of the river Muga into the lagoon after ~1250 cal AD. This caused its transformation into a freshwater lake, increased nutrient load, and the infilling and drainage of a great part of the lagoon. By tracking the shift towards an anthropogenically-controlled system around ~750 yr ago, this study points out Mediterranean lagoons as ancient and heavily-modified systems, with anthropogenic impacts and controls covering multi-centennial and even millennial timescales. Finally, we contributed to the future construction of reliable seashell-based chronologies in NE Spain by calibrating the

  10. Analysis of the Szczecin Lagoon waters fungi

    Directory of Open Access Journals (Sweden)

    Waldemar Dąbrowski

    2014-08-01

    Full Text Available Quantitative and qualitative analysis of the Szczecin Lagoon waters was carried out between April and December 1996. Changes in yeasts numbers of this particular estuary were found to be typical for the marinę and estuary waters with maximum concentration of yeast-like fungi in the summer season. Qualitative analysis of the isolated strains, proved Rhodotorula glutinis to be the most frequently isolated species at the three sampling sites, with Candida coliculosa dominating at the forth one.

  11. Shear strength, consolidation and drainage of colliery tailings lagoons

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, J M

    1980-01-01

    The shear strength and consolidation characteristics of colliery tailings were related to the structure of the lagoon deposits. First, a theoretical investigation of vane shear tests in layered media is outlined, and then cone penetration tests are considered as an alternative tool for measuring strengths in situ. The geochemistry and sedimentology of colliery lagoons were investigated. The in-situ permeability of lagoons was also investigated and the results used to investigate the drainage characteristics. Finally, overtipping was investigated.

  12. Ecosystem level assessment of the Grand Calumet Lagoons, Indiana Dunes National Lakeshore

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, P.M. [National Biological Service, Porter, IN (United States)

    1995-12-31

    The Grand Calumet Lagoons make up the eastern section of the Grand Calumet River (GCR), Indiana Harbor and Ship Canal and nearshore Lake Michigan Area of Concern (AOC). The GCR AOC is the only one of the 42 Great Lakes Areas of Concern identified by the International Joint Commission with all 14 designated uses classified as impaired. Included within the boundaries of the Indiana Dunes National Lakeshore (INDU), is the central section of the Grand Calumet Lagoons. A number of biotic and abiotic factors were tested to determine the effects of an industrial landfill that borders the lagoons to assess the potential impact on park resources. Analysis included water quality testing, assessments of macroinvertebrate, fish, algae and aquatic plant communities and contaminant concentrations in water, sediment and plant and fish tissue. Surface water testing found very few contaminants, but significantly higher nutrient levels were found in the water column closest to the landfill. Macroinvertebrate, aquatic plant and fish communities all showed significant impairment in relationship to their proximity to the landfill. Aquatic plant growth habit became limited next to the landfill with certain growth habits disappearing entirely. Aquatic plants collected close to the landfill had high concentrations of several heavy metals in their stems and shoots. Using the index of biotic integrity (IBI), fish community assessment indicated impairment in the areas adjacent to the landfill. Sediments tested at one site had over 12% polycyclic aromatic hydrocarbons (PAH) and carp (Cyprinus carpio) collected from this site had whole fish tissue concentrations over 1 mg/kg PAH.

  13. Comparison of Water Flows in Four European Lagoon Catchments under a Set of Future Climate Scenarios

    Directory of Open Access Journals (Sweden)

    Cornelia Hesse

    2015-02-01

    Full Text Available Climate change is supposed to remarkably affect the water resources of coastal lagoons as they are highly vulnerable to changes occurring at their catchment and/or ocean or sea boundaries. Probable impacts of projected climate changes on catchment hydrology and freshwater input were assessed using the eco-hydrological model SWIM (Soil and Water Integrated Model for the drainage areas of four European lagoons: Ria de Aveiro (Portugal, Mar Menor (Spain, Tyligulskyi Liman (Ukraine and Vistula Lagoon (Poland/Russia under a set of 15 climate scenarios covering the time period until the year 2100. Climate change signals for all regions show continuously increasing trends in temperature, but various trends in precipitation. Precipitation is projected to decrease in two catchments on the Iberian Peninsula and increase in the Baltic region catchment, and does not show a clear trend in the catchment located near the Black Sea. The average projected changes in freshwater inputs reflect these changes in climate conditions, but often show variability between the scenarios, in future periods, and within the catchments. According to the individual degrees of water management influences in the four drainage basins, the climate sensitivity of river inflows is differently pronounced in each.

  14. Sludge storage lagoon biogas recovery and use. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Muller, D.; Norville, C. [Memphis and Shelby County Div. of Planning and Development, TN (United States)

    1991-07-01

    The City of Memphis has two wastewater treatment plants. The SWTP employs two large anaerobic digestion sludge lagoons as part of the overall sludge treatment system. Although these lagoons are effective in concentrating and digesting sludge, they can generate offensive odors. The SWTP uses aerobic digesters to partially stabilize the sludge and help reduce objectionable odors before it enters the lagoons. The anaerobic digestion of sludge in the lagoons results in the dispersion of a large quantity of biogas into the atmosphere. The City realized that if the lagoons could be covered, the odor problem could be resolved, and at the same, time, biogas could be recovered and utilized as a source of energy. In 1987, the City commissioned ADI International to conduct a feasibility study to evaluate alternative methods of covering the lagoons and recovering and utilizing the biogas. The study recommended that the project be developed in two phases: (1) recovery of the biogas and (2) utilization of the biogas. Phase 1 consists of covering the two lagoons with an insulated membrane to control odor and temperature and collect the biogas. Phase 1 was found to be economically feasible and offered a unique opportunity for the City to save substantial operating costs at the treatment facility. The Memphis biogas recovery project is the only application in the world where a membrane cover has been used on a municipal wastewater sludge lagoon. It is also the largest lagoon cover system in the world.

  15. Test plan: the Czechowice Oil Refinery bioremediation demonstration of a process waste lagoon

    Energy Technology Data Exchange (ETDEWEB)

    Altman, D.J.; Lombard, K.H.; Hazen, T.C.

    1997-03-31

    The remediation strategies that will be applied at the Czechowice Oil Refinery waste lagoon in Czechowice, Poland are designed, managed, and implemented under the direction of the Westinghouse Savannah River Company (WSRC) for the United States Department of Energy (DOE). WSRC will be assisted in the demonstration by The Institute for Ecology of Industrial Areas (IETU). This collaboration between IETU and DOE will provide the basis for international technology transfer of new and innovative remediation technologies that can be applied in Poland and the Eastern European Region as well.

  16. Bioaccumulation of mercury in reared and wild Ruditapes philippinarum of a Mediterranean lagoon

    Science.gov (United States)

    Giani, Michele; Rampazzo, Federico; Berto, Daniela; Maggi, Chiara; Mao, Andrea; Horvat, Milena; Emili, Andrea; Covelli, Stefano

    2012-11-01

    The Marano and Grado lagoon, one of the largest wetlands in the Mediterranean Sea, has been subject to mercury contamination by industrial and mining activities. This must be considered a severe threat for Manila clam harvesting, which is an important fishing and commercial activity in the area. Contamination levels and potential risk for human consumption both in reared and wild clams collected from the lagoon were assessed by analyzing total mercury (THg) and methylmercury (MeHg) contents. In addition, relationships between THg and MeHg in sediments and in the bivalves were investigated. Increased bioaccumulation of THg but not of MeHg with increasing size of wild clam populations was observed at most sites. Higher concentrations both of THg (605 ± 210 ng g-1 ww) and MeHg (147 ± 37 ng g-1 ww) were detected in the eastern lagoon where the highest THg contents in sediments were observed as a consequence of the long-term supply of cinnabar rich suspended material from the Isonzo river. The variation of Hg content in seeded Manila clams during growth was monitored over a period of 18 months at two sites of the western sector of the lagoon. Results showed that the two areas were suitable for clam farming, with THg levels in reared bivalves always lower than the 0.5 mg kg-1 ww European Community limit. At the same time, as clams grew bigger in size, their THg and MeHg concentrations decreased, becoming lower than in the starting seeded pool. Reared clams presented lower THg (84 ± 55 ng g-1 ww) and MeHg (44.1 ± 24.6 ng g-1 ww) content than wild clams of the same commercial size (>30 mm). Based on a precautionary approach, intake of Hg and MeHg with the estimated clam consumption does not seem to constitute a risk for human health in the studied area.

  17. Partitioning, bioavailability and origin of heavy metals from the Nador Lagoon sediments (Morocco) as a basis for their management

    Science.gov (United States)

    González, I.; Águila, E.; Galán, E.

    2007-08-01

    Nador Lagoon sediments show low trace element concentrations, and, in relation to the lagoon geochemical baseline, only some anomalies for As, Cd, Cu and Pb in the NW of the lagoon deserve to be outstanding. The distribution of major, minor and trace elements in the lagoon allows a breakdown in four zones. Between “Beni Ensar” and “Atelouane” (zone A), a quite confined zone rich in organic matter and S, the most important trace-element anomalies (As, Cd, Co, Cu, Mn, Pb, Zn) were found, mainly around industry and old mining activities. In the surrounding of the city of Nador (zone B), the anomalies correspond to Mn, Cu and Zn. The coastal barrier and Kebdana channel (zone C) show moderately concentrations of Cd, Cr and Ni at specific sites. The less polluted area is the SE of the lagoon (zone D), with no outstanding anomaly. In lagoon sediments, metal bioavailability is very low. The metal partitioning patterns show that Cu, Pb and Zn present a low availability because they are bounded to the residual, non-mobile phases of the sediments. Only in some sites, the fraction was associated with organic matter, which could be liberated easily. Arsenic is concentrated in both the residual phases and the organic matter, the latter being more available. Cadmium is mainly concentrated in some samples in the interchangeable fraction, which could be considered as a potentially toxic element because it is easily released. Concerning the origin of these trace elements, those found in zone A correspond mostly to a natural source by weathering of mount Gourougou volcanic rocks (As, Co, Cu, Pb and Zn), and to an anthropogenic origin (Cd) owing to the presence of industry and old mines. In zone B, contributions of Cu and Zn enter the lagoon through soil weathering and river-borne, and as anthropogenic pollution from urban wastes. In zone C the most important pollutant is Cd deduced to be of anthropogenic origin from the close industry and intensive agriculture area. In spite

  18. Effects of groundwater levels and headwater wetlands on streamflow in the Charlie Creek basin, Peace River watershed, west-central Florida

    Science.gov (United States)

    Lee, T.M.; Sacks, L.A.; Hughes, J.D.

    2010-01-01

    The Charlie Creek basin was studied from April 2004 to December 2005 to better understand how groundwater levels in the underlying aquifers and storage and overflow of water from headwater wetlands preserve the streamflows exiting this least-developed tributary basin of the Peace River watershed. The hydrogeologic framework, physical characteristics, and streamflow were described and quantified for five subbasins of the 330-square mile Charlie Creek basin, allowing the contribution of its headwaters area and tributary subbasins to be separately quantified. A MIKE SHE model simulation of the integrated surface-water and groundwater flow processes in the basin was used to simulate daily streamflow observed over 21 months in 2004 and 2005 at five streamflow stations, and to quantify the monthly and annual water budgets for the five subbasins including the changing amount of water stored in wetlands. Groundwater heads were mapped in Zone 2 of the intermediate aquifer system and in the Upper Floridan aquifer, and were used to interpret the location of artesian head conditions in the Charlie Creek basin and its relation to streamflow. Artesian conditions in the intermediate aquifer system induce upward groundwater flow into the surficial aquifer and help sustain base flow which supplies about two-thirds of the streamflow from the Charlie Creek basin. Seepage measurements confirmed seepage inflow to Charlie Creek during the study period. The upper half of the basin, comprised largely of the Upper Charlie Creek subbasin, has lower runoff potential than the lower basin, more storage of runoff in wetlands, and periodically generates no streamflow. Artesian head conditions in the intermediate aquifer system were widespread in the upper half of the Charlie Creek basin, preventing downward leakage from expansive areas of wetlands and enabling them to act as headwaters to Charlie Creek once their storage requirements were met. Currently, the dynamic balance between wetland

  19. Florida sinkhole index

    OpenAIRE

    Spencer, Steven; Lane, Ed.

    1995-01-01

    The following data were compiled from the Florida Sinkhole Research Institute data base. That database, which contains approximately 1900 sinkholes, is available from the Florida Geological Survey upon request. The data are arranged alphabetically by county. The first two digits of the identification number represents the county. These numbers correspond to the Florida Department of Transportation county numbering system. Following the county number are three numbers which represe...

  20. Research objectives to support the South Florida Ecosystem Restoration initiative-Water Conservation Areas, Lake Okeechobee, and the East/West waterways

    OpenAIRE

    Kitchens, Wiley M.

    1994-01-01

    The South Florida Ecosystem encompasses an area of approximately 28,000 km2 comprising at least 11 major physiographic provinces, including the Kissimmee River Valley, Lake Okeechobee, the Immokalee Rise, the Big Cypress, the Everglades, Florida Bay, the Atlantic Coastal Ridge, Biscayne Bay, the Florida Keys, the Florida Reef Tract, and nearshore coastal waters. South Florida is a heterogeneous system of wetlands, uplands, coastal areas, and marine areas, dominated by the watershe...

  1. Lake size and fish diversity in southern Brazil coastal lagoons

    Directory of Open Access Journals (Sweden)

    Lucia Ribeiro Rodrigues

    2015-10-01

    Full Text Available The coastal plain of Rio Grande do Sul, southern Brazil, presents a series of shallow lagoons with diverse size and morphology. The objective of this study is to determine whether the size of the lagoon is an effective factor for structuring fish diversity. In this regard, nine lagoons with distinct areas were sampled: three with an area up to 40 hectares, three with area between 40 and 80 hectares, and three with an area of over 80 hectares. Each lagoon was sampled once on the littoral and pelagic zones. At each point, fish were captured through a set of gill nets with different mesh sizes. Captured specimens were identified, quantified and evaluated for weight and length. A total of 24 fish species belonging to 10 families was obtained, with Characidae presenting the highest species richness. Cyanocharax alburnus was the only species that occurred in all lagoons. Cyphocharax voga, Astyanax eigenmmaniorum, Oligosarcus jenynsii and O. robustus were also frequent species, present in most of the sampled lagoons. Lycengraulis grossidens was captured in just two lagoons with increased conductivity. The community structure showed the highest species richness in lakes with an area over 40 ha, however the highest mean diversity values were observed in ponds up to 40 ha. Cluster Analysis yielded the formation of two groups: a group formed by just one lagoon and a second one cluster grouping all the other lagoons. This pattern may be associated with the presence of Lycengraulis grossidens as a dominant species in this lagoon clustered apart. The results indicate that lagoons with up to 40 ha present greater homogeneity on the species composition and higher average values of diversity; while intermediate ponds (between 40 and 80 ha have lower average diversity for the fish fauna due to increased heterogeneity in species abundance.

  2. Florida Energy Assurance Plan

    Science.gov (United States)

    Turner, Niescja E.; Murtagh, William; Guthrie, Kevin; Nykyri, Katariina; Radasky, William A.; Senkowicz, Eric

    2012-08-01

    This spring, Florida held the nation's first statewide emergency preparedness training and exercises geared specifically to the aftermath of severe geomagnetic events. Funded by the State of Florida Division of Emergency Management (FDEM) via a Department of Energy grant and held in collaboration with Watch House International, Inquesta Corporation, and the Florida Institute of Technology, the 17-19 April 2012 workshop had 99 on-site attendees in an oceanfront hotel in Melbourne, Florida, as well as 16 over live Web streaming. The workshop was the capstone to a three-month season of 21 regional space weather training sessions and workshops serving 386 attendees in total.

  3. Biogeochemical cycling and phyto- and bacterioplankton communities in a large and shallow tropical lagoon (Términos Lagoon, Mexico) under 2009-2010 El Niño Modoki drought conditions

    Science.gov (United States)

    Conan, Pascal; Pujo-Pay, Mireille; Agab, Marina; Calva-Benítez, Laura; Chifflet, Sandrine; Douillet, Pascal; Dussud, Claire; Fichez, Renaud; Grenz, Christian; Gutierrez Mendieta, Francisco; Origel-Moreno, Montserrat; Rodríguez-Blanco, Arturo; Sauret, Caroline; Severin, Tatiana; Tedetti, Marc; Torres Alvarado, Rocío; Ghiglione, Jean-François

    2017-03-01

    The 2009-2010 period was marked by an episode of intense drought known as the El Niño Modoki event. Sampling of the Términos Lagoon (Mexico) was carried out in November 2009 in order to understand the influence of these particular environmental conditions on organic matter fluxes within the lagoon's pelagic ecosystem and, more specifically, on the relationship between phyto- and bacterioplankton communities. The measurements presented here concern biogeochemical parameters (nutrients, dissolved and particulate organic matter [POM], and dissolved polycyclic aromatic hydrocarbons [PAHs]), phytoplankton (biomass and photosynthesis), and bacteria (diversity and abundance, including PAH degradation bacteria and ectoenzymatic activities). During the studied period, the water column of the Términos Lagoon functioned globally as a sink and, more precisely, as a nitrogen assimilator. This was due to the high production of particulate and dissolved organic matter (DOM), even though exportation of autochthonous matter to the Gulf of Mexico was weak. We found that bottom-up control accounted for a large portion of the variability of phytoplankton productivity. Nitrogen and phosphorus stoichiometry mostly accounted for the heterogeneity in phytoplankton and free-living prokaryote distribution in the lagoon. In the eastern part, we found a clear decoupling between areas enriched in dissolved inorganic nitrogen near the Puerto Real coastal inlet and areas enriched in phosphate (PO4) near the Candelaria estuary. Such a decoupling limited the potential for primary production, resulting in an accumulation of dissolved organic carbon and nitrogen (DOC and DON, respectively) near the river mouths. In the western part of the lagoon, maximal phytoplankton development resulted from bacterial activity transforming particulate organic phosphorus (PP) and dissolved organic phosphorus (DOP) to available PO4 and the coupling between Palizada River inputs of nitrate (NO3) and PP. The

  4. Physical Characterization of Florida International University Simulants

    Energy Technology Data Exchange (ETDEWEB)

    HANSEN, ERICHK.

    2004-08-19

    Florida International University shipped Laponite, clay (bentonite and kaolin blend), and Quality Assurance Requirements Document AZ-101 simulants to the Savannah River Technology Center for physical characterization and to report the results. The objectives of the task were to measure the physical properties of the fluids provided by FIU and to report the results. The physical properties were measured using the approved River Protection Project Waste Treatment Plant characterization procedure [Ref. 1]. This task was conducted in response to the work outlined in CCN066794 [Ref. 2], authored by Gary Smith and William Graves of RPP-WTP.

  5. Seasonal hydrochemical variation in a tropical coastal lagoon (Açu Lagoon, Brazil

    Directory of Open Access Journals (Sweden)

    G. G. Chagas

    Full Text Available Hydrochemical conditions in the Açu Lagoon are described using spatial and temporal variations of various limnological variables (water temperature, dissolved oxygen, electric conductivity, total alkalinity, carbon dioxide, dissolved and total nutrients (N, P and Si, and chlorophyll a. Collected data was used in order to understand the structure and functioning of an enclosed coastal lagoon strongly influenced by climatic conditions. Water samples were collected monthly (November 1999-December 2000 in five sampling stations established along the lagoon. A decreasing spatial gradient of electrical conductivity was observed beginning from a sand bar region between the lagoon and the sea in the direction of the sweet-water input area. The positive correlation observed between the pH and dissolved oxygen (DO values, and the negative one observed between pH values and those of carbon dioxide (CO2, evidenced coupled biological processes, e.g., primary production and decomposition. Both spatial and temporal variation of dissolved nutrients showed fast increase and decrease in the beginning of summer, suggesting that nutrient input resulting from rainfall stimulates phytoplankton production, as reflected by chlorophyll a concentration increase.

  6. Are coastal lagoons physically or biologically controlled ecosystems? Revisiting r vs. K strategies in coastal lagoons and estuaries

    Science.gov (United States)

    Pérez-Ruzafa, Angel; Marcos, Concepción; Pérez-Ruzafa, Isabel María; Pérez-Marcos, María

    2013-11-01

    Environmental stress influences biological assemblages, with species responding to stress by adopting particular life-history strategies (e.g., r vs. K). Coastal lagoons and estuaries are considered naturally stressed and physically controlled systems with frequent environmental disturbances and fluctuations. At the same time, their transitional nature (between terrestrial, freshwater and marine) makes them especially vulnerable to human impacts and land and freshwater inputs. As a result, it is hypothesised that residents of coastal lagoons would display characteristics of r-selected species. The r-strategy involves increased reproductive effort through early reproduction, small and numerous offspring with a large dispersive capability, short lifespan and small adult body size. Together, these traits provide a selective advantage in such unpredictable or short-lived environments. Alternatively, immigrants to coastal lagoons should mostly be K-strategists, with a competitive advantage over the r-strategists, at least on a temporary time scale. These hypotheses were explored using a dataset from 73 Atlanto-Mediterranean sites: 27 estuaries, 42 coastal lagoons and 4 from the sea, obtained from published sources. A detailed analysis of the distributions of the different resident fish species according to lagoon characteristics indicated that in lagoons with a higher marine influence the families Gobiidae, Blenniidae and Syngnathidae were common, while lagoons with freshwater influence are characterized by Cyprinidae and other freshwater species. In analyzing the biological strategies of lagoon species we found that fish assemblages inhabiting marine influenced lagoons were characterized by solitary, necto-benthonic sedentary species. These species are often hermaphroditic, with benthic broods and many exhibit brooding behaviour. This suggests that marine influenced lagoons are dominated by K-strategist species, while r-strategy species will be more common in

  7. Assessment of Water Quality Parameters of Kpeshie Lagoon of Ghana

    African Journals Online (AJOL)

    A study was carried out on the Kpeshi Lagoon to identify the chemical and physical characteristics of the water. A lot of industrial activities are carried out around the Lagoon and it is being gradually turned into a place of refuse damp. Standard methods were used for determining of chemical and physical characteristics of ...

  8. DESIGN INFORMATION REPORT: PROTECTION OF WASTEWATER LAGOON INTERIOR SLOPES

    Science.gov (United States)

    A problem common to many wastewater treatment and storage lagoons is erosion of the interior slopes. Erosion may be caused by surface runoff and wind-induced wave action. The soils that compose the steep interior slopes of lagoons are especially susceptible to erosion and slumpin...

  9. Distributions of phytoplankton in a coastal lagoon of Mahin, Ondo ...

    African Journals Online (AJOL)

    Distributions of phytoplankton were investigated in Mahin Lagoon within Transgressive mud coast of Ondo, Western Nigeria. Collections and analyses of samples of phytoplankton and surface waters (for some physico-chemical parameters) were done at fifteen stations along the stretch of the lagoon in October 2013 and ...

  10. Scottish saline lagoons: Impacts and challenges of climate change

    Science.gov (United States)

    Angus, Stewart

    2017-11-01

    The majority of Scotland's saline lagoons are located on the low-lying coastlines of the Western Isles and the northern archipelagos of Orkney and Shetland, where recorded annual relative sea level rise rates are among the highest in Scotland. The sediment-impounded lagoons of Orkney and Shetland will either lose their impoundment and become incorporated in marine coastal waters, or become increasingly saline, as relative sea levels rise. The rock-basin lagoons of the Western Isles will retain their restricted exchange with the sea but will also become more saline with rising sea level. Specialist lagoonal organisms tend to have wide salinity tolerances but may succumb to competition from marine counterparts. In all areas, there are sufficient fresh-water inland water bodies with potential to be captured as lagoons to compensate for loss of extent and number, but the specialist lagoon biota tend to have limited dispersal powers. It is thus possible that they will be unable to transfer to their analogue sites before existing lagoons become fully marine, giving conservation managers the problem of deciding on management options: leave natural processes to operate without interference, manage the saline inflow to maintain the current salinity regime, or translocate lagoon organisms perceived as threatened by rising salinities. Timing of conversion and capture is unpredictable due to local topography and complications caused by variable stratification.

  11. The Florida Seagrass Integrated Mapping and Monitoring (SIMM) Program: Indications of the effects of regional climate variability on these vital ecosystems

    Science.gov (United States)

    Yarbro, L.; Carlson, P. R., Jr.

    2016-12-01

    The SIMM program was developed to protect and manage seagrass resources in Florida by providing a collaborative vehicle for seagrass mapping, monitoring, data sharing, and reporting. We summarize and interpret mapping data and field assessments of seagrass abundance and diversity and water quality gathered by regional scientists and managers who work in estuaries from the Panhandle to the northeast Florida coast. Since 2013, regional reports summarizing the status and trends of seagrass ecosystems have been available on the web. The format provides current information for a wide stakeholder community. Ongoing collaborative efforts of more than 30 seagrass researchers and managers provide timely information on environmental and ecosystem changes in these important systems. Since the first published seagrass assessments in 2009, we have observed large changes in seagrass abundance and diversity in several regions; most but not all changes were likely due to variations in water quality that determine the light available to benthic vegetation. In the Panhandle and the Big Bend, in 2012-2104, increases in the frequency and severity of storms and resulting runoff reduced water quality which in turn decreased the abundance and distribution of seagrasses. The storm pattern resulted from changes in the subtropical jet stream and persisted for 3 years. In south Florida, heat and drought elevated salinities to extreme levels in Florida Bay in 2015; the resulting stratification along with high temperatures caused die-off of thousands of hectares of seagrass in the north central Bay. Extremely wet conditions in southeast Florida in 2015-2016 strained the water management system, resulting in large releases of polluted freshwater to estuaries on the southwest and southeast coasts, reducing light availability and causing large blooms of noxious algae. While other regions have also experienced algal blooms that reduced available light (Indian River Lagoon), seagrasses have

  12. Clipperton, a possible future for atoll lagoons

    Science.gov (United States)

    Charpy, L.; Rodier, M.; Couté, A.; Perrette-Gallet, C.; Bley-Loëz, C.

    2010-09-01

    Closure of the Clipperton Island atoll (10°17' N 109°13' W), now a meromictic lake, is estimated to have occurred between 1839 and 1849. It was still closed in 2005. Brackish waters in the upper layer (0-10 m) were oxygenated, while saline waters in the deep layer (>20 m) were anoxic. Allowing for the methodological difficulties of earlier measurements, the physical characteristics of the lagoon did not seem to have changed significantly since the last expedition (1980). The intermediate layer between brackish and saline waters was characterized by a strong density gradient and a temperature inversion of up to 1.6°C. Microbial activity, water exchange between the deep layer and surrounding oceanic waters and the geothermal flux hypothesis are discussed. The low DIN and SRP concentrations observed in the upper layer, despite high nutrient input by seabird droppings, reflect the high nutrient uptake by primary producers as attested by the elevated overall gross primary production (6.6 g C m-2 day-1), and high suspended photosynthetic biomass (2.23 ± 0.23 μg Chl a l-1) and production (263 ± 27 μg C l-1 day-1). Phytoplankton composition changed in 67 years with the advent of new taxa and the disappearance of previously recorded species. The freshwater phytoplanktonic community comprised 43 taxa: 37 newly identified during the expedition and 6 previously noted; 16 species previously found were not seen in 2005. The closure of the lagoon, combined with the positive precipitation-evaporation budget characteristic of the region, has induced drastic changes in lagoon functioning compared with other closed atolls.

  13. Spatial variability of primary organic sources regulates ichthyofauna distribution despite seasonal influence in Terminos lagoon and continental shelf of Campeche, Mexico

    Science.gov (United States)

    Romo Rios, J. A.; Aguíñiga-García, S.; Sanchez, A.; Zetina-Rejón, M.; Arreguín-Sánchez, F.; Tripp-Valdéz, A.; Galeana-Cortazár, A.

    2013-05-01

    Human activities have strong impacts on coastal ecosystems functioning through their effect on primary organic sources distributions and resulting biodiversity. Hence, it appears to be of utmost importance to quantify contribution of primary producers to sediment organic matter (SOM) spatial variability and its associated ichthyofauna. The Terminos lagoon (Gulf of Mexico) is a tropical estuary severely impacted by human activities even though of primary concern for its biodiversity, its habitats, and its resource supply. Stable isotope data (d13C, d15N) from mangrove, seaweed, seagrass, phytoplankton, ichthyofauna and SOM were sampled in four zones of the lagoon and the continental shelf through windy (November to February), dry (March to June) and rainy (July to October) seasons. Stable Isotope Analysis in R (SIAR) mixing model were used to determine relative contributions of the autotrophic sources to the ichthyofauna and SOM. Analysis of variance of ichthyofauna isotopic values showed significant differences (P < 0.001) in the four zones of lagoon despite the variability introduced by the windy, dry and rainy seasons. In lagoons rivers discharge zone, the mangrove contribution to ichthyofauna was 40% and 84% to SOM. Alternative use of habitat by ichthyofauna was evidenced since in the deep area of the lagoon (4 m), the contribution of mangrove to fish is 50%, and meanwhile contribution to SOM is only 77%. Although phytoplankton (43%) and seaweed (41%) contributions to the adjacent continental shelf ichthyofauna were the main organic sources, there was 37% mangrove contribution to SOM, demonstrating conspicuous terrigenous influence from lagoon ecosystem. Our results point toward organic sources spatial variations that regulate fish distribution. In Terminos lagoon, significant correlation (p-value = 0.2141 and r=0.79) of Ariopsis felis and Sphoeroides testudineus abundances and seaweed and seagrasses contributions (30-35%) during both dry and rainy seasons

  14. The Role of Terrestrial Inputs of Organic Matter in Arctic Lagoons: Comparative Studies from Open-Water and Ice-Covered Periods

    Science.gov (United States)

    Dunton, K. H.; McClelland, J. W.; Connelly, T.; Linn, S.; Khosh, M.

    2012-12-01

    Coastal ecosystems of the Arctic receive extraordinarily large quantities of terrestrial organic matter through river discharge and shoreline erosion. This organic matter, both in dissolved and particulate form, may provide an important carbon and energy subsidy that supports and maintains heterotrophic activity and food webs in coastal waters, especially in the lagoons. Recent food web studies using stable isotopes confirm the significant assimilation of terrestrial organic matter, based on the depletion in both 13C and 15N content of invertebrate and vertebrate consumers collected in eastern Beaufort Sea lagoons vs. offshore waters. Our current work specifically focuses on a set of 12 field sites along the eastern Alaskan Beaufort Sea coast, from Barter Island to Demarcation Bay. To examine linkages between biological communities and organic matter inputs from land, we compared sites ranging from lagoons to open coastal systems that receive differing amounts of freshwater runoff and also differ markedly in their exchange characteristics with shelf waters. Our temporal and spatial effort included field sampling during the ice covered period in a number of lagoons characterized by differences in their exchange characteristics with the nearshore shelf. Our preliminary chemical and biological measurements, the first of their kind in arctic coastal lagoons, reveal that lagoon benthos can become hypersaline (43) and net heterotrophic (values to 30% oxygen saturation) during winter, before rebounding during the period of ice break-up to net autotrophic (>100% saturation) under continued hypersaline conditions. Measurements of water and sediment chemistry, benthic and water column community characteristics, and natural abundance isotopic tracers promise to reveal the dynamic nature of these productive lagoon ecosystems under different hydrologic conditions. The possible role of terrestrially derived carbon to arctic estuarine food webs is especially important in view of

  15. The marsh vegetation of Kleinmond Lagoon

    Directory of Open Access Journals (Sweden)

    M. O'Callaghan

    1994-10-01

    Full Text Available The vegetation of Kleinmond Lagoon suggests that this system is in transition from an estuary to a coastal lake. Two major types of vegetation were recognized, one which is subjected to soil and water conditions of marine origin and the other which is subjected to conditions of terrestrial origin. These vegetation types are discussed and compared to the vegetation of other estuarine systems. Artificial manipulations of the mouth seem to have resulted in sediment deposition and a freshening of the system. These unseasonable manipulations also threaten the continued existence of a number of species in the system.

  16. 'Florida Beauty' strawberry

    Science.gov (United States)

    Florida Beauty’ strawberry (Fragaria x ananassa) originated from a 2012 cross made by the Queensland breeding program between Queensland Australia selection 2010-119 (female parent) and ‘Florida Radiance’ (male parent). Selection 2010-119 was chosen as a parent for its excellent fruit shape and fl...

  17. Acid Tar Lagoons: Management and Recovery

    Science.gov (United States)

    Bohers, Anna; Hroncová, Emília; Ladomerský, Juraj

    2017-04-01

    This contribution presents the issue with possibility of definitive removal of dangerous environmental burden in Slovakia - serious historical problem of two acid tar lagoons. In relation to their removal, no technology has been found so far - technologically and economically suitable, what caused problems with its management. Locality Predajná is well known in Slovakia by its character of contrasts: it is situated in the picturesque landscape of National Park buffer zone of Nízke Tatry, on the other site it is contaminated by 229 211m3 of acid tar with its characteristics of toxicity, carcinogenicity, teratogenicity, mutagenicity and toxicity especially for animals and plants. Acid tar in two landfills with depth of 1m in case of the first lagoon and 9,5m in case of the second lagoon is a waste product derived from operation of Petrochema Dubová - refinery and petrochemical plant whose activity was to process the crude oil through processes of sulfonation and adsorption technology for producing lubricating and special oils, synthetic detergents and special white oils for cosmetic and medical purposes. A part of acid tar was incinerated in two incineration plats. Concentration of SO2 in combustion gases was too high and it was not possible to decrease it under the value of 2000 mg.mn-3 [LADOMERSKÝ, J. - SAMEŠOVÁ, D.: Reduction in sulfur dioxide emissions waste gases of incineration plant. Acta facultatis ecologiae. 1999, p. 217-223]. That is why it was necessary to put them out of operation. Later, because of public opposition it was not possible to build a new incineration plat corresponding to the state of the art. Even though actual Slovak and European legislative for protection of environment against such impacts, neither of tried methods - bio or non-biologic treatment methods - was proved as suitable for processing or for recovery in the reason of different factors admission: i.e. strong aggressivity, difficulty with handling because of its sludgy and

  18. A preliminary investigation of the distribution of heavy metals in surface sediments of the Cona tidal marsh (Venice Lagoon)

    International Nuclear Information System (INIS)

    Bernardi, S.; Costa, F.; Vazzoler, S.; Zonta, R.

    1988-01-01

    Data are from the two series of surface sediment sampling in an interface area between the Venice Lagoon and the mainland. The distribution of heavy metals gives a correlation with polluted sourcesites-identified in the channel systems with a highly polluted input-and allows us to identify the localities of accumulation. Restricted to the estuary of the river tributary transporting a high concentration of pollutants into a tidal marsh area of the lagoon, the study shows the effect of the fresh water forcing to distribute heavy metals on surface sediments. Within the scope of this preliminary investigation, indications from sampling identify a sector of the 'palude of Cona' in this estuary, which is highly suitable for detailed studies on precesses affecting heavy-metal distributions in bottom surface sediments of shallow-water areas

  19. Overview of ecotoxicological studies performed in the Venice Lagoon (Italy).

    Science.gov (United States)

    Losso, C; Ghirardini, A Volpi

    2010-01-01

    This work reports on the state of the art of the bioindicators used to assess environmental quality (regarding chemical pollutant impacts) in the Venice lagoon. After a brief description of the roles, advantages and limitations of bioindicators in marine and transitional environments and a summary of the Venice lagoon characteristics, the ecotoxicological methods used during scientific studies and research projects in the Lagoon are reported. Since not all data are available and no database can be formulated, the main evidence from toxicity bioassays, biomarkers and bioaccumulation analyses since the end of the 1970s is spatially synthesized using maps and discussed according to the four Venice lagoon basins. The majority of indicators showed that the Lido basin (north-central lagoon), affected by the presence of the industrial area and the city of Venice, is the one most highly impacted (particularly in the sites located within or in front of the industrial area, which showed very high sediment toxicity and high levels of DNA damage). The Malamocco basin (south-central lagoon) seems to be the least problematic. The southern basin (Chioggia basin) was shown to be impacted by urban contaminants from the town of Chioggia. The northern basin (Treporti basin) presented both impacted sites (high toxicity and high bioaccumulation factor) and relatively unpolluted sites (absence of toxicity, absence of imposex and low levels of bioaccumulation). This review can serve as a basis on which to select pragmatic, cost-effective biomonitoring techniques for environmental effects in lagoon ecosystems.

  20. Hydrodynamics Modeling of Khung Krabaen Lagoon, Chanthaburi Province, Thailand

    Directory of Open Access Journals (Sweden)

    Tanuspong Pokavanich

    2018-01-01

    Full Text Available Khung Krabaen Lagoon (KKBL is a small low-inflow water body. There are vast areas of tidal flat occupied nearly 60% of the lagoon that host some of the most productive seagrass habitats in the region. The lagoon is surrounded by mangrove forest and intensive shrimp farms behind it. The KKBL was used as an intake and recipient water for the farms. However due some shrimp disease epidemics and possibly deteriorated water quality, the farms are now taking the intake water from the outer sea through very expensive (to construct and to maintain irrigation system. Objective of this study is to investigate the KKBL’s hydrodynamics using a numerical simulation model validated with measured data. The simulation model was setup two-dimensionally based on the Delft3D model. Results suggested that water currents inside, at the mouth and at the outer sea of the lagoon are mainly governed by tide and wind. Offshore of the lagoon, there are strong tidal currents flowing along northwest and southeast direction. The tidal currents flow into the lagoon through its mouth before dispersion rapidly inside the lagoon. Mean circulation largely varied seasonally and had direct correlations outer sea seasonal mean currents and the monsoons.

  1. Silica in invasive wetland plant species of lagoons, Côte d'Ivoire: Spatio-temporal patterns

    Science.gov (United States)

    José-mathieu Koné, Yéfanlan; Schoelynck, Jonas

    2017-04-01

    Tropical wetlands are known to accumulate a large quantity of Biogenic Silica (BSi) produced by wetland plant species (Struyf et al., 2015), and approximately 70-80% of the total supply of Dissolved Si (DSi) to the coastal zone occurs in (sub) tropical river systems (Jennerjahn et al. 2006). However, the data at these latitudes are limited. Here, we present the BSi concentration from eleven invasive macrophyte species randomly collected in three small ( 800ha) lagoons of Côte d'Ivoire during 12 months. Our data showed a large spatio-temporal variability of BSi in the three lagoons with no consistent trends. In general, the BSi concentrations obtained were high and values ranged from 0 to 54 mg g-1 through the entire sampling period, with the highest values found in Acroceras zizaniodes (emergent species of Poaceae). In general, free floating species had significantly less BSi than emergent species (Pspecies of fern, Salviniaceae) at the young stage were similar to those found in the emergent species. Based on yearly averages, highest BSi values were observed in Kodjoboué lagoon, and the lowest in the Ono lagoon that is 80% covered by macrophytes. Moreover, the dissolved silica (DSi) concentrations were systematically higher in Ono Lagoon than in Kodjoboué Lagoon. We conclude that in an eutrophic system Si accumulating in aquatic macrophytes is not related to Si availability but to other environmental factors. Jennerjahn, T.C., Knoppers, B.A., de Souze, W.F.L., Brunskill, G.J., Silva, E.I.L., Adi, S. et al., 2006. Factors controlling dissolved silica in tropical rivers. In: Ittekot, V. (ed) The silicon cycle. Island Press, Washington, D. C, pp 29-51 Schoelynck J and Struyf E, 2016. Silicon in aquatic vegetation. Functional Ecology. 30: 1323-1330. Struyf, E., Mosimane, K., Van Pelt, D., Murray-Hudson, M., Meire, P., Frings, P., Wolski, P., Schaller, J., Gondwe, M.J., Schoelynck, J. and Conley, D.J., 2015. The role of vegetation in the Okavango Delta silica sink

  2. Evaluation of pollution levels due to the use of consumer fertilizers under Florida conditions : summary.

    Science.gov (United States)

    2010-01-01

    Many surface waters in Florida are polluted with excessive nitrogen and phosphorus. Applied as fertilizer to turf and landscape plants, excess nutrients are deposited into rivers, lakes, and other surface waters through stormwater runoff. These nutri...

  3. Cinnabar presence ar round the Valentin stream in Florida district of Uruguay

    International Nuclear Information System (INIS)

    Sanchez, L.

    1993-01-01

    Some little grains of cinnabar were found in Valentin River, Florida, Uruguay during the Gold Exploration Project on the Area in 1991. We present some chemical data to prove the existence of mercury probably related to a greissen hydrothermal event.

  4. The dominance of cyanobacteria in Mediterranean hypereutrophic lagoons: a case study of Cabras Lagoon (Sardinia, Italy

    Directory of Open Access Journals (Sweden)

    Silvia Pulina

    2011-02-01

    Full Text Available An intense proliferation of cyanobacteria in Cabras Lagoon was investigated over a period of two years (July 2007 to June 2009. The influence of environmental and meteorological parameters in the lagoon on temporal variations in cyanobacteria orders was assessed. For 17 months, Chroococcales was the only cyanobacterial order observed in the lagoon. Cyanobium-type cells (Reynolds functional group Z were the most abundant phytoplankton taxon during this period. In the following months, drastic changes in the cyanobacteria assemblages occurred simultaneously with constant, intense rainfall that led to a sudden drop in the lagoon’s salinity. The succession of autumn–winter Oscillatoriales (Planktothrix sp. and Pseudanabaena catenata; Reynolds functional group S1 and late spring growth of Nostocales (Aphanizomenon gracile, Aphanizomenon aphanizomenoides, and Anabaenopsis circularis; Reynolds functional group H1 was monitored. Canonical Correspondence Analysis was carried out to quantify the influence of environmental variables, and indicated strong relationships between Chroococcales and salinity, Oscillatoriales and higher values of SRP and the DIN/SRP ratio, and Nostocales and lower nutrient concentrations, the DIN/SRP ratio and salinity.

  5. Is the Venice Lagoon Noisy? First Passive Listening Monitoring of the Venice Lagoon: Possible Effects on the Typical Fish Community.

    Science.gov (United States)

    Bolgan, Marta; Picciulin, Marta; Codarin, Antonio; Fiorin, Riccardo; Zucchetta, Matteo; Malavasi, Stefano

    2016-01-01

    Three passive listening surveys have been carried out in two of the three Venice lagoon tide inlets and inside the Venice island. The spectral content and the intensity level of the underwater noise as well as the presence or absence of Sciaena umbra and the distribution of its different sound patterns have been investigated in all the recording sites. The passive listening proved to be successful in detecting S. umbra drumming sounds in both Venice lagoon tide inlets. Our results indicate that the spectral content and the level of underwater noise pollution in the Venice lagoon could affect fish acoustic communication.

  6. Radioecology of the Kuecuek Cekmece lagoon

    International Nuclear Information System (INIS)

    Unlu, Y.M.

    1977-01-01

    In order to understand the physical-chemical conditions of the Kuecuekcekmece Lagon starting with its creation, meteorological, physical, chemical and biological conditions were determined. Radiometric analyses have been done on the dissected organs of animals which lives in the lagoon and sediments. The effect of the variation of salinity on the accumulationloss and distribution of 65 Zn in mussel (Mytilus galloprovincialis Lam.) were investigated. Besides of this, determination and comparison of 65 Zn flux rates in Mytilus galloprovincialis in the field and laboratory conditions are made. The results shows that, mixing of both marine and stream water the salinity and elemental composition of the Lagoon change frequently. This events has an influence on the 65 Zn precipitation. Remaining the salinities under the 10 ppt and the pH as an alkali, the 65 Zn adsorption to the small particle became to conciderable quantities. Since Mytilus galloprovincialis feeds itself by fittering the water, we would expect that it would accumulate more activity in such a medium. In contrast to this, less activities accumulated in low salinities and this accumulation is seen mostly in the shells. although the reason for this event cannot be explained as a whole, it can be expressed in two way according to : During adaptation of organisms to the new conditions by its isosmotical ability, some events takes place in the organisms which cause more strongly bounding of the existing zinc in the body. It is for this reason, 65 Zn cannot be able to change with body Zn. The radioactive zinc is not biologically available to the M. galloprovincialis at low salinities

  7. VISTA Stares Deeply into the Blue Lagoon

    Science.gov (United States)

    2011-01-01

    This new infrared image of the Lagoon Nebula was captured as part of a five-year study of the Milky Way using ESO's VISTA telescope at the Paranal Observatory in Chile. This is a small piece of a much larger image of the region surrounding the nebula, which is, in turn, only one part of a huge survey. Astronomers are currently using ESO's Visible and Infrared Survey Telescope for Astronomy (VISTA) to scour the Milky Way's central regions for variable objects and map its structure in greater detail than ever before. This huge survey is called VISTA Variables in the Via Lactea (VVV) [1]. The new infrared image presented here was taken as part of this survey. It shows the stellar nursery called the Lagoon Nebula (also known as Messier 8, see eso0936), which lies about 4000-5000 light-years away in the constellation of Sagittarius (the Archer). Infrared observations allow astronomers to peer behind the veil of dust that prevents them from seeing celestial objects in visible light. This is because visible light, which has a wavelength that is about the same size as the dust particles, is strongly scattered, but the longer wavelength infrared light can pass through the dust largely unscathed. VISTA, with its 4.1-metre diameter mirror - the largest survey telescope in the world - is dedicated to surveying large areas of the sky at near-infrared wavelengths deeply and quickly. It is therefore ideally suited to studying star birth. Stars typically form in large molecular clouds of gas and dust, which collapse under their own weight. The Lagoon Nebula, however, is also home to a number of much more compact regions of collapsing gas and dust, called Bok globules [2]. These dark clouds are so dense that, even in the infrared, they can block the starlight from background stars. But the most famous dark feature in the nebula, for which it is named, is the lagoon-shaped dust lane that winds its way through the glowing cloud of gas. Hot, young stars, which give off intense

  8. assessment of water quality parameters of kpeshi lagoon of ghana

    African Journals Online (AJOL)

    User

    A lot of industrial activities are carried out around the Lagoon and it is being gradually ... chemical and physical characteristics of water samples. .... Royal Hotel whereas the third section stretches .... for long in the environment (WRC, 2003).

  9. Physicochemical and microbiological monitoring analysis of the Iquipari Lagoon

    Directory of Open Access Journals (Sweden)

    Rafael Batista Justino

    2017-12-01

    Full Text Available The state of Rio de Janeiro holds many coastal lagoons with an extensive biodiversity. The lagoons are considered productive, but also defenseless due anthropic use. They can be great economic sources, as well as an ideal place for leisure and recreation. In order to evaluate the water quality of the Iquipari Lagoon, located in the city of São João da Barra, RJ, this work aims to demonstrate the results of physicochemical and microbiological parameters, and to discuss the results of the analysis. It was possible to observe that the parameters such as thermotolerant coliforms, pH and Turbidity (UNT showed high values established by CONAMA No. 357/05. However, it is necessary to give special attention to environmental education in the locality, as well as to encourage preservation of the natural environment in which the lagoon is located.

  10. Nutrient removal from swine lagoon effluent by duckweed

    Energy Technology Data Exchange (ETDEWEB)

    Bergmann, B.A.; Cheng, J.; Classen, J.; Stomp, A.M.

    2000-04-01

    Three duckweed geographic isolates were grown on varying concentrations of swine lagoon effluent in a greenhouse to determine their ability to remove nutrients from the effluent. Duckweed biomass was harvested every other day over a 12-day period. Duckweed biomass production, nutrient loss from the swine lagoon effluent, and nutrient content of duckweed biomass were used to identify effluent concentrations/geographic isolate combinations that are effective in terms of nutrient utilization from swine lagoon effluent and production of healthy duckweed biomass. When Lemna minor geographic isolate 8627 was grown on 50% swine lagoon effluent, respective losses of TKN, NH{sub 3}-N, TP, OPO{sub 4}-P, TOC, K, Cu, and Zn were 83, 100, 49, 31, 68, 21, 28 and 67%.

  11. Social foraging by waterbirds in shallow coastal lagoons in Ghana

    NARCIS (Netherlands)

    Battley, PF; Poot, M; Wiersma, P; Gordon, C; Ntiamoa-Baidu, Y; Piersma, T; Battley, Phil F.

    Social foraging in waterbirds in Ghanaian coastal lagoons was studied during October and November 1994. Two types of foraging were social: directionally synchronized flocks (often involving distinctive feeding methods used in unison) and dense pecking aggregations. Social flocks were typically

  12. Air--sea gaseous exchange of PCB at the Venice lagoon (Italy).

    Science.gov (United States)

    Manodori, L; Gambaro, A; Moret, I; Capodaglio, G; Cescon, P

    2007-10-01

    Water bodies are important storage media for persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) and this function is increased in coastal regions because their inputs are higher than those to the open sea. The air-water interface is extensively involved with the global cycling of PCBs because it is the place where they accumulate due to depositional processes and where they may be emitted by gaseous exchange. In this work the parallel collection of air, microlayer and sub-superficial water samples was performed in July 2005 at a site in the Venice lagoon to evaluate the summer gaseous flux of PCBs. The total concentration of PCBs (sum of 118 congeners) in air varies from 87 to 273 pg m(-3), whereas in the operationally defined dissolved phase of microlayer and sub-superficial water samples it varies from 159 to 391 pg L(-1). No significant enrichment of dissolved PCB into the microlayer has been observed, although a preferential accumulation of most hydrophobic congeners occurs. Due to this behaviour, we believe that the modified two-layer model was the most suitable approach for the evaluation of the flux at the air-sea interface, because it takes into account the influence of the microlayer. From its application it appears that PCB volatilize from the lagoon waters with a net flux varying from 58 to 195 ng m(-2)d(-1) (uncertainty: +/-50-64%) due to the strong influence of wind speed. This flux is greater than those reported in the literature for the atmospheric deposition and rivers input and reveals that PCB are actively emitted from the Venice lagoon in summer months.

  13. Phosphate gypsum wastes in Venice lagoon. Radiological impact

    International Nuclear Information System (INIS)

    Belli, M; Blasi, M; Guogang, J.; Rosamilia, S.; Sansone, U.; Biancotto, R.; Bidoli, P.; Sepulcri, D.

    2000-03-01

    The phosphoric minerals utilized in phosphoric acid production, presents high concentrations of radioactive materials: U238, Th 232, K 40. The phosphogypsum is the waste material obtained in the phosphoric acid production in wet process. This type of production method is employed for many years in Venice lagoon (Porto Marghera chemical plants). In this paper are reported evaluations of radiological impact on aquatic environment of lagoon [it

  14. Gaining insight into Clipperton's lagoon hydrology using tritium

    OpenAIRE

    Jean-baptiste, Philippe; Fourre, Elise; Charlou, Jean-luc; Donval, Jean-pierre; Correge, Thierry

    2009-01-01

    Historical descriptions of the Clipperton lagoon appear to converge on the fact that it became isolated from the surrounding ocean around 1858. Since then, because of the high precipitation rate which largely exceeds evaporation in this region of the eastern tropical Pacific, a brackish lens has formed on top of the saline oceanic waters. In 1980, literature data show that the thickness of this water body was reaching 14 m. During the 2005 Etienne's Clipperton expedition, we collected lagoon ...

  15. Seychelles Lagoon Provides Corals with a Refuge from Bleaching

    Directory of Open Access Journals (Sweden)

    David Iluz

    2008-01-01

    Full Text Available An extensive bleaching event in the summer of the year 1997-1998 affected most reefs along East Africa's shores. In the aftermath of that episode, the reefs of Île Alphonse in the Seychelles were examined and it was found that reefs along the seaward slopes of the island lost >95% of their branching coral colonies, with considerably higher survival of massive species. Île Alphonse features a nearly circular shallow lagoon, with steep seaward slopes. Contrary to our expectations, mortality in the warmer lagoon was far lower than of coral colonies on the surrounding slopes, bathed in deeper and cooler waters. We suggest that corals in the lagoon were protected from UV radiation by leachate stemming from seagrass leaves steeped in the lagoon. Our measurements in the lagoon showed a strong attenuation of ultraviolet radiation, not observed in the waters outside the lagoon, and laboratory examination confirmed that the strong UV absorption of substances leached into seawater from decomposing leaves of the seagrass Thalassodendron (=Cymodocea testudinaceum. Our findings demonstrate the synergism between elevated seawater temperature and UV radiation in triggering bleaching on shallow reefs.

  16. Seychelles Lagoon Provides Corals with a Refuge from Bleaching

    International Nuclear Information System (INIS)

    Iluz, D.; Chadwick, N.E.; Hoffman, R.; Dubinsky, Z.; Vago, R.; Chadwick, N.E.; Chadwick, N.E.

    2008-01-01

    An extensive bleaching event in the summer of the year 1997-1998 affected most reefs along East Africa's shores. In the aftermath of that episode, the reefs of Ile Alphonse in the Seychelles were examined and it was found that reefs along the seaward slopes of the island lost >95% of their branching coral colonies, with considerably higher survival of massive species. Ile Alphonse features a nearly circular shallow lagoon, with steep seaward slopes. Contrary to our expectations, mortality in the warmer lagoon was far lower than of coral colonies on the surrounding slopes, bathed in deeper and cooler waters. We suggest that corals in the lagoon were protected from UV radiation by leachate stemming from sea grass leaves steeped in the lagoon. Our measurements in the lagoon showed a strong attenuation of ultraviolet radiation, no observed in the waters outside the lagoon, and laboratory examination confirmed that the strong UV absorption of substances leached into seawater from decomposing leaves of the sea grass Thalassodendron (=Cymodocea) testudinaceum. Our findings demonstrate the synergism between elevated seawater temperature and UV radiation in triggering bleaching on shallow reefs.

  17. Chemical composition of sediments from the Patos Lagoon, Brazil

    International Nuclear Information System (INIS)

    Baisch, P.R.M.; Asmus, H.E.; Jounneau, J.-M.

    1989-01-01

    Analysis of major elements (Si,Al,Fe,Mg,Mn,Ca,Ti,K,Na), trace elements (Pb,Cu,Zn,Ni,Cr,Zr,Ba,Rb,Sr,Co,Ga) and organic matter (C-org.; N-org., S and P), and of bottom sediments from the Patos Lagoon, aim to define the regional geochemical variables of this lagoon. The results identified three main groups of trace elements: 1) trace elements associated with argillo-mineral and with organic matter: Zn, Ni, Cr, Rb; 2) trace elements of detrital origin: Ti, Za, Ba; and 3) trace elements connected exclusively to organic matter: Mn, Cu, Co. The results of this study also demonstrate the main regional variations of the major and trace elements, of the organic matter and of the sedimentary grain size along a north-south profile in the lagoon. Organic matter is the most important factor for the distribution of trace elements. The Guaiba hydrographic system is the main source for the detrital and non-detrital trace elements in the lagoon. Gradual sedimentation along the Patos Lagoon can be pointed to as the cause of higher concentrations of Pb, Cu and Cr (partial fraction) in the southern part of the lagoon. (author) [pt

  18. METALS POLLLUTION IN EL LIMON LAGOON, CHIAPAS, MEXICO

    Directory of Open Access Journals (Sweden)

    Ma. Teresa Leal-Ascencio

    2009-04-01

    Full Text Available El Limón Lagoon belongs to the Reforma county, in the State of Chiapas, Mexico. Massive fish killings have occurred in the lagoon, demanding a deeper study to determine the pollution state of the lagoon, as well as the possible cause of the deaths. Results show that the average concentrations of Zn, Ni, Cr, Cd and Cu in the lagoon are beyond the recommended limits in Canada and USA to avoid deleterious biological effects in aquatic species. Special mention has to be done for the case of Zn, with a maximum concentration of 1360 mg/kg, presumably associated with the use of this metal as a catalyst in a natural gas plant close to the lagoon. Although the industrial discharges comply with the Mexican Standards for metals in wastewaters, this has not been enough to avoid the accumulation of metals in sediments, which is a demonstration of failure of the Mexican Wastewater Standards that should be more restrictive especially in the case of lagoons with a low water recharge, taking into account the type of water body where the wastewater is loading. In the case of the application of this water for agriculture, the metals can accumulate in soils, with unwanted effects on crops.

  19. Organochlorines in the Vaccares Lagoon trophic web (Biosphere Reserve of Camargue, France)

    Energy Technology Data Exchange (ETDEWEB)

    Roche, H., E-mail: helene.roche@u-psud.f [Ecologie, Systematique et Evolution, UMR8079 CNRS, Universite Paris-Sud, AgroParisTech, F91405 Orsay Cedex (France); Vollaire, Y.; Persic, A.; Buet, A. [Ecologie, Systematique et Evolution, UMR8079 CNRS, Universite Paris-Sud, AgroParisTech, F91405 Orsay Cedex (France); Oliveira-Ribeiro, C. [Departamento de Biologia Celular, Universidade Federal do Parana, Caixa Postal 19031, CEP: 81.531-990, Curitiba, PR (Brazil); Coulet, E. [Nature Reserve of Camargue, La Capeliere, F13200 Arles (France); Banas, D.; Ramade, F. [Ecologie, Systematique et Evolution, UMR8079 CNRS, Universite Paris-Sud, AgroParisTech, F91405 Orsay Cedex (France)

    2009-08-15

    During a decade (1996-2006), ecotoxicological studies were carried out in biota of the Vaccares Lagoon (Biosphere Reserve in Rhone Delta, France). A multicontamination was shown at all levels of the trophic web due to a direct bioconcentration of chemical from the medium combined with a food transfer. Here, the pollutants investigated were organochlorines, among which many compounds banned or in the course of prohibition (or restriction) (PCB, lindane, pp'-DDE, dieldrin, aldrin, heptachlor, endosulfan...) and some substances likely still used in the Rhone River basin (diuron, fipronil). The results confirmed the ubiquity of contamination. It proves to be chronic, variable and tends to regress; however contamination levels depend on the trophic compartment. A biomagnification process was showed. A comparison of investigation methods used in other Mediterranean wetlands provides basis of discussion, and demonstrates the urgent need of modelling to assess the ecotoxicological risk in order to improve the management of such protected areas. - The Vaccares Lagoon trophic web biomagnifies organochlorine pollutants.

  20. First report of endosymbionts in Dreissena polymorpha from the brackish Curonian Lagoon, SE Baltic Sea

    Directory of Open Access Journals (Sweden)

    Romualda Chuševė

    2012-11-01

    Full Text Available We report the first results of a parasitological study ofDreissena polymorpha (zebra mussels from the brackishCuronian Lagoon, SE Baltic Sea. Zebra mussels were collected monthlyfrom May to October 2011 from a site near the mouth of the River Nemunas.Three types of endosymbionts were found in the mantle cavity andvisceral mass of the molluscs during dissections, i.e. thecommensal ciliate Conchophthirus acuminatus and parasitic ciliateOphryoglena sp., and rarely encountered, unidentified nematodes.The abundances of C. cuminatus and Ophryoglena sp.were positively associated with host shell length and watertemperature, but no effect of water salinity was detected.As the endosymbionts are either highly host-specific to zebra mussels(C. acuminatus and Ophryoglena sp. or are probablyfree-living organisms that inadvertently infect the molluscs (nematodes,we conclude that the presence of D. polymorpha in theCuronian Lagoon does not pose any serious parasitologicalrisk to native biota. We emphasize, however, that this conclusionshould be treated with caution as it is based on a study conductedonly at a single location. Our work extends the currentlyscarce records of D. polymorpha parasites and commensals frombrackish waters, and adds to a better understanding of the ecologicalimpact this highly invasive mollusc causes in the areas it has invaded.

  1. A review of the influence of biogeography, riverine linkages, and marine connectivity on fish assemblages in evolving lagoons and lakes of coastal southern Africa.

    Science.gov (United States)

    Whitfield, Alan K; Weerts, Steven P; Weyl, Olaf L F

    2017-09-01

    The Holocene evolution of eight South African coastal lakes and lagoons is examined and related to changes in fish composition over that period. Historical and current connectivity with riverine and marine environments are the primary determinants of present-day fish assemblages in these systems. A small and remarkably consistent group of relict estuarine species have persisted in these coastal lakes and lagoons. The loss or reduction of connectivity with the sea has impacted on the diversity of marine fishes in all eight study systems, with no marine fishes occurring in those water bodies where connectivity has been completely broken (e.g. Sibaya, Groenvlei). In systems that have retained tenuous linkages with the sea (e.g., Verlorenvlei, Wilderness lakes), elements of the marine fish assemblage have persisted, especially the presence of facultative catadromous species. Freshwater fish diversity in coastal lakes and lagoons is a function of historical and present biogeography and salinity. From a freshwater biogeography perspective, the inflowing rivers of the four temperate systems reviewed here contain three or fewer native freshwater fishes, while the subtropical lakes that are fed by river systems contain up to 40 freshwater fish species. Thus, the significantly higher fish species diversity in subtropical versus temperate coastal lakes and lagoons comes as no surprise. Fish species diversity has been increased further in some systems (e.g., Groenvlei) by alien fish introductions. However, the impacts of fish introductions and translocations have not been studied in the coastal lakes and lagoons of South Africa. In these closed systems, it is probable that predation impacts on small estuarine fishes are significant. The recent alien fish introductions is an example of the growing threats to these systems during the Anthropocene, a period when human activities have had significant negative impacts and show potential to match the changes recorded during the

  2. Determination of nitrate pollution sources in the Marano Lagoon (Italy) by using a combined approach of hydrochemical and isotopic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Saccon, Pierpaolo; Leis, Albrecht [JOANNEUM RESEARCH Forschungsgesellschaft mbH, Institute for Water, Energy and Sustainability, 8010 Graz (Austria); Marca, Alina; Kaiser, Jan; Campisi, Laura [School of Environmental Sciences, University of East Anglia, NR4 7TJ Norwich (United Kingdom); Boettcher, Michael E.; Escher, Peter [Leibniz Institute for Baltic Sea Research (IOW), Geochemistry and Isotope Geochemistry Group, D-18119 Rostock (Germany); Savarino, Joel; Erbland, Joseph [UJF-Grenoble 1/CNRS-INSU, Laboratoire de Glaciologie et Geophysique de l' Environnement (LGGE) UMR 5183 (France); Eisenhauer, Anton [GEOMAR, Helmholtz Zentrum fuer Ozean Forschung Kiel, Wischhofstr. 1-3, 24148 Kiel (Germany)

    2013-07-01

    Due to increased pollution by nitrate from intensive agricultural and other anthropogenic activities the Marano lagoon (northeast Italy) and part of its catchment area have been investigated, applying a combined approach of hydrochemical and isotopic techniques. Thus, to identify and characterize the potential multiple-sources of nitrate pollution the isotopic compositions of nitrate (δ{sup 15}N, δ{sup 18}O, and Δ{sup 17}O), boron (δ{sup 11}B), water (δ{sup 2}H and δ{sup 18}O), and sulphate (δ{sup 34}S and δ{sup 18}O), as well as the chemical composition of different water types have been determined. In the monitoring program water samples from the lagoon, its tributary rivers, the groundwater upwelling line, groundwater, sewage, and open sea on a quarterly interval from 2009 to 2010 have been collected and analyzed. Coupling isotopic and hydrochemical results indicate that the nitrate load in the lagoon was not only derived from agriculture activities but also from other sources such as urban wastewaters, in situ nitrification, and atmospheric deposition. However, none of the samples showed the isotopic characteristics of synthetic fertilizers. (authors)

  3. Drivers of pCO2 dynamics in two contrasting coral reef lagoons: The influence of submarine groundwater discharge (Invited)

    Science.gov (United States)

    Cyronak, T.; Santos, I. R.; Erler, D.; Maher, D. T.; Eyre, B.

    2013-12-01

    The carbon chemistry of coral reef lagoons can be highly variable over short time scales. While much of the diel variability in seawater carbon chemistry is explained by biological processes, external sources such as river and groundwater seepage may deliver large amounts of organic and inorganic carbon to coral reefs and represent a poorly understood feedback to ocean acidification. Here, we assess the impact of submarine groundwater discharge (SGD) on pCO2 variability in two coral reef lagoons with distinct SGD driving mechanisms. Diel variability of pCO2 in the two ecosystems was explained by a combination of biological drivers and SGD inputs. In Rarotonga, a South Pacific volcanic island, SGD was driven primarily by a steep terrestrial hydraulic gradient, and the lagoon was influenced by the high pCO2 (5,501 μatm) of the fresh groundwater. In Heron Island, a Great Barrier Reef coral cay, SGD was dominated by seawater recirculation through sediments (i.e. tidal pumping) and pCO2 was mainly impacted through the stimulation of biological processes. The Rarotonga water column had a relatively higher average pCO2 (549 μatm) than Heron Island (471 μatm). However, pCO2 exhibited a greater diel range in Heron Island (778 μatm) than in Rarotonga (507 μatm). The Rarotonga lagoon received 31.2 mmol CO2 m-2 d-1 from SGD, while the Heron Island lagoon received 12.3 mmol CO2 m-2 d-1. Over the course of this study both systems were sources of CO2 to the atmosphere (3.00 to 9.67 mmol CO2 m-2 d-1), with SGD-derived CO2 contributing a large portion to the air-sea CO2 flux. The relationship between both water column pH and aragonite saturation state (ΩAr) and radon (222Rn) concentrations indicate that SGD may enhance the local acidification of some coral reef lagoons. Studies measuring the carbon chemistry of coral reefs (e.g. community metabolism, calcification rates) may need to consider SGD-derived CO2.

  4. Klawock Lagoon, Alaska Benthic Habitats 2011 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  5. Klawock Lagoon, Alaska Benthic Habitats 2011 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  6. Klawock Lagoon, Alaska Benthic Habitats 2011 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  7. Klawock Lagoon, Alaska Benthic Habitats 2011 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  8. Woodville Karst Plain, North Florida

    OpenAIRE

    2006-01-01

    Map showing the largest mapped underwater cave systems and conduit flow paths confirmed by tracer testing relative to surface streams, sinkholes and potentiometric surface of the Florida aquifer in the Woodville Karst Plain, Florida

  9. Ecological Impacts of the Space Shuttle Program at John F. Kennedy Space Center, Florida

    Science.gov (United States)

    Hall, Carlton R.; Schmalzer, Paul A.; Breininger, David R.; Duncan, Brean W.; Drese, John H.; Scheidt, Doug A.; Lowers, Russ H.; Reyier, Eric A.; Holloway-Adkins, Karen G.; Oddy, Donna M.; hide

    2014-01-01

    The Space Shuttle Program was one of NASAs first major undertakings to fall under the environmental impact analysis and documentation requirements of the National Environmental Policy Act of 1969 (NEPA). Space Shuttle Program activities at John F. Kennedy Space Center (KSC) and the associated Merritt Island National Wildlife Refuge (MINWR) contributed directly and indirectly to both negative and positive ecological trends in the region through the long-term, stable expenditure of resources over the 40 year program life cycle. These expenditures provided support to regional growth and development in conjunction with other sources that altered land use patterns, eliminated and modified habitats, and contributed to cultural eutrophication of the Indian River Lagoon. At KSC, most Space Shuttle Program related actions were conducted in previously developed facilities and industrial areas with the exception of the construction of the shuttle landing facility (SLF) and the space station processing facility (SSPF). Launch and operations impacts were minimal as a result of the low annual launch rate. The majority of concerns identified during the NEPA process such as potential weather modification, acid rain off site, and local climate change did not occur. Launch impacts from deposition of HCl and particulates were assimilated as a result of the high buffering capacity of the system and low launch and loading rates. Metals deposition from exhaust deposition did not display acute impacts. Sub-lethal effects are being investigated as part of the Resource Conservation and Recovery Act (RCRA) regulatory process. Major positive Space Shuttle Program effects were derived from the adequate resources available at the Center to implement the numerous environmental laws and regulations designed to enhance the quality of the environment and minimize impacts from human activities. This included reduced discharges of domestic and industrial wastewater, creation of stormwater management

  10. Response of early Ruppia cirrhosa litter breakdown to nutrient addition in a coastal lagoon affected by agricultural runoff

    Science.gov (United States)

    Menéndez, Margarita

    2009-05-01

    The response of early Ruppia cirrhosa Petagna (Grande) litter decomposition to external nitrogen and phosphorus availability in La Tancada (Ebro River, NE Spain), a coastal lagoon that receives agricultural freshwater runoff from rice fields has been examined. Recently abscised dead R. cirrhosa stems were collected and 25 g of fresh weight was placed in litter bags with a mesh size of 100 μm and 1 mm. These bags were fertilised by adding nitrogen (N), a mixture of nitrogen plus phosphorus (N + P), or phosphorus (P), or were left untreated (CT). Macroinvertebrates were retrieved from the bags and the ash-free dry weight, and carbon, and N and P content of the remaining plant material were measured after 0, 3, 7, 14, 22 and 32 days. Litter decomposition rates, k (day -1), were estimated using a simple exponential model. Litter decay was clearly accelerated by the addition of P in the fine (100 μm) litter bags (0.042), but when N was added alone (0.0099) the decomposition rate was lower than in the CT treatments (0.022). No significant difference was observed between the N (0.0099-0.018) and N + P (0.0091-0.015) treatments in either the fine or the coarse (1 mm) litter bags. These results could be attributed to the relatively high availability of external (environmental) and internal (detritus contents) N. No significant effect of macro invertebrates was observed in the CT treatment or under N or P or N + P addition. The ratio between the decomposition rates in coarse and fine litter bags (k c/k f) was lower in disturbed Tancada lagoon (0.82) than in Cesine lagoon (2.11), a similar Mediterranean coastal water body with almost pristine conditions. These results indicate that, in addition to data on macroinvertebrate community structure, decomposition rates could also be used to assess water quality in coastal lagoons.

  11. Rapid proliferation of Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio cholerae during freshwater flash floods in French Mediterranean coastal lagoons.

    Science.gov (United States)

    Esteves, Kevin; Hervio-Heath, Dominique; Mosser, Thomas; Rodier, Claire; Tournoud, Marie-George; Jumas-Bilak, Estelle; Colwell, Rita R; Monfort, Patrick

    2015-11-01

    Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio cholerae of the non-O1/non-O139 serotype are present in coastal lagoons of southern France. In these Mediterranean regions, the rivers have long low-flow periods followed by short-duration or flash floods during and after heavy intense rainstorms, particularly at the end of the summer and in autumn. These floods bring large volumes of freshwater into the lagoons, reducing their salinity. Water temperatures recorded during sampling (15 to 24°C) were favorable for the presence and multiplication of vibrios. In autumn 2011, before heavy rainfalls and flash floods, salinities ranged from 31.4 to 36.1‰ and concentrations of V. parahaemolyticus, V. vulnificus, and V. cholerae varied from 0 to 1.5 × 10(3) most probable number (MPN)/liter, 0.7 to 2.1 × 10(3) MPN/liter, and 0 to 93 MPN/liter, respectively. Following heavy rainstorms that generated severe flash flooding and heavy discharge of freshwater, salinity decreased, reaching 2.2 to 16.4‰ within 15 days, depending on the site, with a concomitant increase in Vibrio concentration to ca. 10(4) MPN/liter. The highest concentrations were reached with salinities between 10 and 20‰ for V. parahaemolyticus, 10 and 15‰ for V. vulnificus, and 5 and 12‰ for V. cholerae. Thus, an abrupt decrease in salinity caused by heavy rainfall and major flooding favored growth of human-pathogenic Vibrio spp. and their proliferation in the Languedocian lagoons. Based on these results, it is recommended that temperature and salinity monitoring be done to predict the presence of these Vibrio spp. in shellfish-harvesting areas of the lagoons. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  12. Trace metals behaviour during salt and fresh water mixing in the Venice Lagoon

    International Nuclear Information System (INIS)

    Ghermandi, G.; Campolieti, D.; Cecchi, R.; Costa, F.; Zaggia, L.; Zonta, R.

    1993-01-01

    Preliminary results of an investigation on trace metals behaviour in the estuarine system of the Dese River (Venice Lagoon) are described. Hydrodynamical and water chemical-physical measurements and PIXE concentrations analysis on size-fractionated samples emphasize the complexity of the processes occurring in the area of salt and fresh water mixing. Suspended load variations in the bottom layer of the water column, which may be mostly ascribed to resuspension, regulate the trace metal concentrations and seem to play a fundamental role in the transport of pollutants in shallow water areas of the estuary. The behaviour of dissolved metals is masked by the presence of suspended matter, but some relationships with chemical-physical variables are distinguishable, furnishing information on the processes affecting their concentration in the system. (orig.)

  13. Spreading and autoecology of the invasive species Gracilaria vermiculophylla (Gracilariales, Rhodophyta) in the lagoons of the north-western Adriatic Sea (Mediterranean Sea, Italy)

    Science.gov (United States)

    Sfriso, A.; Wolf, M. A.; Maistro, S.; Sciuto, K.; Moro, I.

    2012-12-01

    Gracilaria vermiculophylla (Ohmi) Papenfuss, an invasive Rhodophyta recently recorded in the Po Delta lagoons (May 2008), was also found in the Venice lagoon in March 2009 and successively in Pialassa della Baiona (Emilia-Romagna Region) in May 2009. The species has colonized the eutrophic and confined areas of Venice by pleustophytic tangled populations (5-15 kg fwt m-2), replacing the allochthonous species whereas it is absent in the areas characterized by low nutrient availability and high water exchange. In contrast, in the Po Delta lagoons and in Pialassa della Baiona it is present everywhere, also with high water renewal, because of the eutrophication caused by the Po river and the industrial area of Ravenna. This study presents the autoecology and distribution of G. vermiculophylla in the above environments, according to their different eutrophication status, showing its relationship with physico-chemical parameters and nutrient concentrations in water column, pore-water, surface sediments and particulate matter collected by traps in a station of the Venice lagoon (Teneri) sampled monthly during one year. Furthermore, we give new information on its morphology and the high dimorphism between female and male gametophytes and tetrasporophytes.

  14. Florida's forests-2005 update

    Science.gov (United States)

    Mark J. Brown

    2007-01-01

    This bulletin highlights principal findings of an annual inventory of Florida's forests. Data summaries are based on measurements of 60 percent of the plots in the State. Additional data summaries and bulletins will be published as the remaining plots are measured.

  15. Intermittent ephemeral river-breaching

    Science.gov (United States)

    Reniers, A. J.; MacMahan, J. H.; Gallagher, E. L.; Shanks, A.; Morgan, S.; Jarvis, M.; Thornton, E. B.; Brown, J.; Fujimura, A.

    2012-12-01

    In the summer of 2011 we performed a field experiment in Carmel River State Beach, CA, at a time when the intermittent natural breaching of the ephemeral Carmel River occurred due to an unusually rainy period prior to the experiment associated with El Nino. At this time the river would fill the lagoon over the period of a number of days after which a breach would occur. This allowed us to document a number of breaches with unique pre- and post-breach topographic surveys, accompanying ocean and lagoon water elevations as well as extremely high flow (4m/s) velocities in the river mouth during the breaching event. The topographic surveys were obtained with a GPS-equipped backpack mounted on a walking human and show the evolution of the river breaching with a gradually widening and deepening river channel that cuts through the pre-existing beach and berm. The beach face is qualified as a steep with an average beach slope of 1:10 with significant reflection of the incident waves (MacMahan et al., 2012). The wave directions are generally shore normal as the waves refract over the deep canyon that is located offshore of the beach. The tide is mixed semi-diurnal with a range on the order of one meter. Breaching typically occurred during the low-low tide. Grain size is highly variable along the beach with layers of alternating fine and coarse material that could clearly be observed as the river exit channel was cutting through the beach. Large rocky outcroppings buried under the beach sand are also present along certain stretches of the beach controlling the depth of the breaching channel. The changes in the water level measured within the lagoon and the ocean side allows for an estimate of the volume flux associated with the breach as function of morphology, tidal elevation and wave conditions as well as an assessment of the conditions and mechanisms of breach closure, which occurred on the time scale of O(0.5 days). Exploratory model simulations will be presented at the

  16. Mechanism of nitrogen removal in wastewater lagoon: a case study.

    Science.gov (United States)

    Vendramelli, Richard A; Vijay, Saloni; Yuan, Qiuyan

    2017-06-01

    Ammonia being a nutrient facilitates the growth of algae in wastewater and causes eutrophication. Nitrate poses health risk if it is present in drinking water. Hence, nitrogen removal from wastewater is required. Lagoon wastewater treatment systems have become common in Canada these days. The study was conducted to understand the nitrogen removal mechanisms from the existing wastewater treatment lagoon system in the town of Lorette, Manitoba. The lagoon system consists of two primary aerated cells and two secondary unaerated cells. Surface samples were collected periodically from lagoon cells and analysed from 5 May 2015 to 9 November 2015. The windward and leeward sides of the ponds were sampled and the results were averaged. It was found that the free ammonia volatilization to the atmosphere is responsible for most of the ammonia removal. Ammonia and nitrate assimilation into biomass and biological growth in the cells appears to be the other mechanisms of nitrogen removal over the monitoring period. Factors affecting the nitrogen removal efficiency were found to be pH, temperature and hydraulic residence time. Also, the ammonia concentration in the effluent from the wastewater treatment lagoon was compared with the regulatory standard.

  17. Fine and coarse components in surface sediments from Bikini Lagoon

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V. E., LLNL

    1997-01-01

    In 1979, 21 years after the moratorium on nuclear testing in the Marshall Islands, surface sediment samples (to depths of 2 and 4 cm) were collected from 87 locations in the lagoon of Bikini Atoll, one of the two sites in the Marshall Islands used by the United States to test nuclear devices from 1946 through 1958. The main purpose for the collections was to map the distribution of long-lived man-made radionuclides associated with the bottom material. In addition the samples were processed to estimate the fraction of fine and coarse components to show, by comparison, what modifications occurred in the composition since the sediments were first described in samples collected before testing in 1946. Nuclear testing produced more finely divided material that is now found in the surface sediment layer over large areas of the lagoon and especially in regions of the lagoon and reef adjacent to test sites. The 5 cratering events alone at Bikini Atoll redistributed sufficient material to account for the higher inventory of fine material found over the surface 4 cm of the sediment of the lagoon. Although the fraction of fine material in the bottom sediments was altered by the nuclear events, the combined processes of formation, transport and deposition were not sufficiently dynamic to greatly change the general geographical features of the major sedimentary components over most of the lagoon floor.

  18. On the Hydrodynamic Geometry of Flow-Through versus Restricted Lagoons

    Directory of Open Access Journals (Sweden)

    Nikolaos Th. Fourniotis

    2018-02-01

    Full Text Available The classification of a lagoon as a restricted lagoon is shown to depend not solely on its geometry but also on the tidal hydraulics. By numerically simulating the tidal exchange of two lagoons of similar geometrical dimensions, the Nidova lagoon and the Papas lagoon, in Western Greece, subject to very similar tidal forcing, applied to the two tidal inlets in the first case and three in the second, very different residence times are found, namely 2.5 days for the Nidova and 25–30 days for the Papas lagoon. This large difference is attributed to the fact that whereas the Papas lagoon functions as a typical restricted lagoon, in which the water renewal is achieved by mixing in the lagoon of the tidal prism water exchanged within a tidal cycle, the Nidova lagoon functions as a flow-through system because of the differential arrival of the tide at its two tidal inlets. It is suggested that this way of enhancing the flushing rate of a lagoon be considered, whenever possible, when creating a new tidal inlet to the lagoon.

  19. Florida Hydrogen Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Block, David L

    2013-06-30

    The Florida Hydrogen Initiative (FHI) was a research, development and demonstration hydrogen and fuel cell program. The FHI program objectives were to develop Florida?s hydrogen and fuel cell infrastructure and to assist DOE in its hydrogen and fuel cell activities The FHI program funded 12 RD&D projects as follows: Hydrogen Refueling Infrastructure and Rental Car Strategies -- L. Lines, Rollins College This project analyzes strategies for Florida's early stage adaptation of hydrogen-powered public transportation. In particular, the report investigates urban and statewide network of refueling stations and the feasibility of establishing a hydrogen rental-car fleet based in Orlando. Methanol Fuel Cell Vehicle Charging Station at Florida Atlantic University ? M. Fuchs, EnerFuel, Inc. The project objectives were to design, and demonstrate a 10 kWnet proton exchange membrane fuel cell stationary power plant operating on methanol, to achieve an electrical energy efficiency of 32% and to demonstrate transient response time of less than 3 milliseconds. Assessment of Public Understanding of the Hydrogen Economy Through Science Center Exhibits, J. Newman, Orlando Science Center The project objective was to design and build an interactive Science Center exhibit called: ?H2Now: the Great Hydrogen Xchange?. On-site Reformation of Diesel Fuel for Hydrogen Fueling Station Applications ? A. Raissi, Florida Solar Energy Center This project developed an on-demand forecourt hydrogen production technology by catalytically converting high-sulfur hydrocarbon fuels to an essentially sulfur-free gas. The removal of sulfur from reformate is critical since most catalysts used for the steam reformation have limited sulfur tolerance. Chemochromic Hydrogen Leak Detectors for Safety Monitoring ? N. Mohajeri and N. Muradov, Florida Solar Energy Center This project developed and demonstrated a cost-effective and highly selective chemochromic (visual) hydrogen leak detector for safety

  20. 33 CFR 117.263 - Banana River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Banana River. 117.263 Section 117.263 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.263 Banana River. (a) The draw of the Mathers (SR...

  1. Copper complexation capacity in surface waters of the Venice Lagoon.

    Science.gov (United States)

    Delgadillo-Hinojosa, Francisco; Zirino, Alberto; Nasci, Cristina

    2008-10-01

    Total copper (Cu(T)), copper ion activity (pCu) and the copper complexation capacity (CuCC) were determined in samples of seawater collected in July 2003 from the Venice Lagoon. Cu(T) and CuCC showed considerable spatial variability: Cu(T) ranged from 1.8 to 70.0nM, whereas the CuCC varied from 195 to 573nM. pCu values varied from 11.6 to 12.6 and are consistent with those previously reported in estuarine and coastal areas (10.9-14.1). The range of Cu(T) values compares well with those reported in the past in the lagoon and in the adjacent Adriatic Sea. The highest concentrations of Cu(T) were found in samples collected near the industrial area of Porto Marghera, whereas the lowest were measured near the Chioggia and Malamocco inlets, where an intense tidally-driven renewal of seawater takes place. Although CuCC showed a high degree of spatial variability, the values recorded in the Venice Lagoon are comparable to those reported in other estuarine systems. In addition, CuCC was positively correlated with dissolved organic carbon (DOC), suggesting that organic ligands responsible for Cu complexation are part of the bulk organic matter pool in the lagoon. The CuCC:Cu(T) molar ratio was, on average 55:1, indicating that a large excess of complexation capacity exists in the Venice Lagoon. The high levels of CuCC and the narrow range of pCu indicates the importance of the role played by organic ligands in controlling the free ion Cu concentrations in the lagoon, and as a consequence, regulating its availability and/or toxicity.

  2. Subtidal hydrodynamics in a tropical lagoon: A dimensionless numbers approach

    Science.gov (United States)

    Tenorio-Fernandez, L.; Valle-Levinson, A.; Gomez-Valdes, J.

    2018-01-01

    Observations in a tropical lagoon of the Yucatan peninsula motivated a non-dimensional number analysis to examine the relative influence of tidal stress, density gradients and wind stress on subtidal hydrodynamics. A two-month observation period in Chelem Lagoon covered the transition from the dry to the wet season. Chelem Lagoon is influenced by groundwater inputs and exhibits a main sub-basin (central sub-basin), a west sub-basin and an east sub-basin. Subtidal hydrodynamics were associated with horizontal density gradients that were modified seasonally by evaporation, precipitation, and groundwater discharge. A tidal Froude number (Fr0), a Wedderburn number (W), and a Stress ratio (S0) were used to diagnose the relative importance of dominant subtidal driving forces. The Froude number (Fr0) compares tidal forcing and baroclinic forcing through the ratio of tidal stress to longitudinal baroclinic pressure gradient. The Wedderburn number (W) relates wind stress to baroclinicity. The stress ratio (S0) sizes tidal stress and wind stress. S0 is a new diagnostic tool for systems influenced by tides and winds, and represents the main contribution of this research. Results show that spring-tide subtidal flows in the tropical lagoon had log(Fr0) ≫ 0 and log(S0) > 0 , i.e., driven mainly by tidal stresses (advective accelerations). Neap tides showed log(Fr0) ≪ 0 and log(S0) < 0) , i.e., flows driven by baroclinicity, especially at the lagoon heads of the east and west sub-basins. However, when the wind stress intensified over the lagoon, the relative importance of baroclinicity decreased and the wind stress controlled the dynamics (log(W) ≫ 0). Each sub-basin exhibited a different subtidal response, according to the dimensionless numbers. The response depended on the fortnightly tidal cycle, the location and magnitude of groundwater input, and the direction and magnitude of the wind stress.

  3. State Waste Discharge Permit application, 100-N Sewage Lagoon

    International Nuclear Information System (INIS)

    1994-06-01

    As part of the Hanford Federal Facility Agreement and Consent Order negotiations (Ecology et al. 1994), the US Department of Energy, Richland Operations Office, the US Environmental Protection Agency, and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground on the Hanford Site which affect groundwater or have the potential to affect groundwater would be subject to permitting under the structure of Chapter 173--216 (or 173--218 where applicable) of the Washington Administrative Code, the State Waste Discharge Permit Program. As a result of this decision, the Washington State Department of Ecology and the US Department of Energy, Richland Operations Office entered into Consent Order No. DE 91NM-177, (Ecology and DOE-RL 1991). This document constitutes the State Waste Discharge Permit application for the 100-N Sewage Lagoon. Since the influent to the sewer lagoon is domestic waste water, the State Waste Discharge Permit application for Public Owned Treatment Works Discharges to Land was used. Although the 100-N Sewage Lagoon is not a Public Owned Treatment Works, the Public Owned Treatment Works application is more applicable than the application for industrial waste water. The 100-N Sewage Lagoon serves the 100-N Area and other Hanford Site areas by receiving domestic waste from two sources. A network of sanitary sewer piping and lift stations transfers domestic waste water from the 100-N Area buildings directly to the 100-N Sewage Lagoon. Waste is also received by trucks that transport domestic waste pumped from on site septic tanks and holding tanks. Three ponds comprise the 100-N Sewage Lagoon treatment system. These include a lined aeration pond and stabilization pond, as well as an unlined infiltration pond. Both piped-in and trucked-in domestic waste is discharged directly into the aeration pond

  4. Observations of emperor geese feeding at Nelson Lagoon, Alaska

    Science.gov (United States)

    Petersen, Margaret R.

    1983-01-01

    Estuaries along the north side of the Alaska Peninsula provide essential habitat for most of the American population of Emperor Goose (Chen canagica) during migration (Petersen and Gill 1982). Most of the population passes through Nelson Lagoon in spring and fall, with over 40,000 birds recorded there (Gill et al 1981). Little is known about the feeding activity of Emperor Geese while they are in estuaries, and the importance of estuaries as staging areas during spring and fall migration is poorly understood. Here I report observations on the feeding activity of emperor Geese at one estuary (Nelson Lagoon).

  5. Fishing Across the Centuries: What Prospects for the Venice Lagoon?

    OpenAIRE

    Silvestri, Silvia; Pellizzato, M.; Boatto, V.

    2006-01-01

    Fishing has always been an important activity for those Venetians who live near the Lagoon, and it still enjoys an important economic and social role in the region. Over the last few years, however, the fishing industry has been subject to a profound transformation both in the reduction of the variety and the abundance of the species found in the lagoon, and in the change from a complex and well-structured type of activity to one which has become monospecialist, that is based principally on t...

  6. Optical researches for cyanobacteria bloom monitoring in Curonian Lagoon

    Science.gov (United States)

    Shirshin, Evgeny A.; Budylin, Gleb B.; Yakimov, Boris P.; Voloshina, Olga V.; Karabashev, Genrik S.; Evdoshenko, Marina A.; Fadeev, Victor V.

    2016-04-01

    Cyanobacteria bloom is a great ecological problem of Curonian Lagoon and Baltic Sea. The development of novel methods for the on-line control of cyanobacteria concentration and, moreover, for prediction of bloom spreading is of interest for monitoring the state of ecosystem. Here, we report the results of the joint application of hyperspectral measurements and remote sensing of Curonian Lagoon in July 2015 aimed at the assessment of cyanobacteria communities. We show that hyperspectral data allow on-line detection and qualitative estimation of cyanobacteria concentration, while the remote sensing data indicate the possibility of cyanobacteria bloom detection using the spectral features of upwelling irradiation.

  7. National Guidebook for Application of Hydrogeomorphic Assessment to Tidal Fringe Wetlands

    Science.gov (United States)

    1998-12-01

    valleys, barrier islands, lagoons , fjords, and other coastal waterways; receive their water primarily from marine or estuarine sources; and are...range 1-3 m, e.g., the Georgia Bight) (3) Tidally restricted lagoons (e.g., Indian River Lagoon ) d. South Florida (Indian River, Florida, to Cedar...Organic constituents include plant detrital material, benthic micro- and macroinvertebrates , organic films, and animal fecal pellets (Kastler and

  8. Florida statewide radiation study

    International Nuclear Information System (INIS)

    Nagda, N.L.; Koontz, M.D.; Fortmann, R.C.; Schoenborn, W.A.; Mehegan, L.L.

    1987-01-01

    Florida phosphate deposits contain higher levels of uranium than most other soils and rocks, thus exposing the population to higher-than-desirable levels of radon and its short-lived daughters. The Florida Legislature ordered a survey of significant land areas where an environmental radiation standard should be applied. Among other things, the study assessed indoor radon in 6,000 homes, soil radon at 3,000 residences, and all data existing prior to the study. The report explains the purpose of the study, how it was designed and conducted, and its results. It concludes with a discussion of radon/radon decay product equilibrium factor, correlation between indoor and soil radon, and preliminary attempts to develop a safe threshold for soil radon below which few elevated indoor levels would be anticipated

  9. Age, growth, and recruitment patterns of juvenile ladyfish (Elops sp from the east coast of Florida (USA

    Directory of Open Access Journals (Sweden)

    Juan C. Levesque

    2015-11-01

    Full Text Available Ladyfish (Elops sp are a common and economically valuable coastal nearshore species found along coastal beaches, bays, and estuaries of the southeastern United States, and subtropical and tropical regions worldwide. Previously, ladyfish were a substantial bycatch in Florida’s commercial fisheries, but changes in regulations significantly reduced commercial landings. Today, ladyfish are still taken in commercial fisheries in Florida, but many are also taken by recreational anglers. Life-history information and research interest in ladyfish is almost non-existent, especially information on age and growth. Thus, the overarching purpose of this study was to expand our understanding of ladyfish age and growth characteristics. The specific objectives were to describe, for the first time, age, growth, and recruitment patterns of juvenile ladyfish from the east coast of Florida (USA. In the Indian River Lagoon (IRL, annual monthly length-frequency distributions were confounded because a few small individuals recruited throughout the year; monthly length-frequency data generally demonstrated a cyclical pattern. The smallest were collected in September and the largest in May. Post-hoc analysis showed no significant difference in length between August and May, or among the other months. In Volusia County (VC, annual monthly length-frequency distribution demonstrated growth generally occurred from late-winter and spring to summer. The smallest ladyfish were collected in February and the largest in August. On average, the absolute growth rate in the IRL was 36.3 mm in 60 days or 0.605 mm day−1. Cohort-specific daily growth rates, elevations, and coincidentals were similar among sampling years. Cohort-specific growth rates ranged from 1.807 in 1993 to 1.811 mm day−1 in 1994. Overall, growth was best (i.e., goodness of fit described by exponential regression. On average, the absolute growth rate in VC was 28 mm in 150 days or 0.1866 mm day−1. Cohort

  10. Seismic evidence of glacial-age river incision into the Tahaa barrier reef, French Polynesia

    Science.gov (United States)

    Toomey, Michael; Woodruff, Jonathan D.; Ashton, Andrew D.; Perron, J. Taylor

    2016-01-01

    Rivers have long been recognized for their ability to shape reef-bound volcanic islands. On the time-scale of glacial–interglacial sea-level cycles, fluvial incision of exposed barrier reef lagoons may compete with constructional coral growth to shape the coastal geomorphology of ocean islands. However, overprinting of Pleistocene landscapes by Holocene erosion or sedimentation has largely obscured the role lowstand river incision may have played in developing the deep lagoons typical of modern barrier reefs. Here we use high-resolution seismic imagery and core stratigraphy to examine how erosion and/or deposition by upland drainage networks has shaped coastal morphology on Tahaa, a barrier reef-bound island located along the Society Islands hotspot chain in French Polynesia. At Tahaa, we find that many channels, incised into the lagoon floor during Pleistocene sea-level lowstands, are located near the mouths of upstream terrestrial drainages. Steeper antecedent topography appears to have enhanced lowstand fluvial erosion along Tahaa's southwestern coast and maintained a deep pass. During highstands, upland drainages appear to contribute little sediment to refilling accommodation space in the lagoon. Rather, the flushing of fine carbonate sediment out of incised fluvial channels by storms and currents appears to have limited lagoonal infilling and further reinforced development of deep barrier reef lagoons during periods of highstand submersion.

  11. Characterisation of a Tunisian coastal lagoon through hyperspectral ...

    African Journals Online (AJOL)

    In 2008 an optical procedure was developed and applied in Ghar El Melh, a Tunisian lagoon which has been increasingly impacted by pollutant loading, especially from agriculture. In situ hyperspectral irradiance was measured at several stations, from which the apparent optical properties (AOPs), namely the irradiance ...

  12. Assessment of the pollution in Aghien lagoon and its tributaries ...

    African Journals Online (AJOL)

    The influence of the pollutants in surface water quality when used for drinking water is of great concern in many developing countries. This study seeks to characterize the types of pollution in Aghien lagoon and its tributaries. For the sampling, water was taken at a depth of 50 cm from the earth surface. Samples were ...

  13. Invasion of Langebaan Lagoon, South Africa, by Mytilus ...

    African Journals Online (AJOL)

    In 1992 the invasive mussel Mytilus galloprovincialis began establishing beds on the centre sandbanks of Langebaan Lagoon. This global invader had previously been restricted to rocky shores along the South African coastline. In order to investigate the effect of the invasion on naturally-occurring communities, ...

  14. Carrying capacity of Chaetoceros gracilis in Homa Lagoon and the ...

    African Journals Online (AJOL)

    The possibility for nutrient limitation to affect C. gracilis was assessed from two different ecosystems (Izmir Bay and Homa Lagoon). Our goal was to determine the growth rate of all nutrients and the maximum levels of the C. gracilis phytoplankton biomass (the maximum biomass carrying capacity) on the extent of its full ...

  15. Sediment budget in the Lagoon of Venice, Italy

    OpenAIRE

    Sarretta, Alessandro; Pillon, Simone; Molinaroli, Emanuela; Guerzoni, Stefano; Fontolan, Giorgio

    2009-01-01

    This is the accepted manuscript of the paper "Sediment budget in the Lagoon of Venice, Italy", published ad final paper in "Continental Shelf Research Volume 30, Issue 8, 15 May 2010, Pages 934-9499" (https://doi.org/10.1016/j.csr.2009.07.002)

  16. 9 Nutrient Load of the Sakumo Lagoon.cdr

    African Journals Online (AJOL)

    Administrator

    nutrients studied, phosphates were the highest in the Sakumo lagoon. The decreasing ... (2008), used nutrient and the trophic status to assess the ... the level of nutrient pollution of the Ramsar site. Materials and ... In assessing the nutrient load, water samples of the .... tidal waves resulting in sea water intrusion may account ...

  17. Boron, calcium and magnesium in Kavaratti lagoon water, Lakshadweep Archipelago

    Digital Repository Service at National Institute of Oceanography (India)

    Nasnolkar, C.M.; Salkar, V.R.; Shirodkar, P.V.; Abidi, S.A.H.

    1228.8 to 1319.8 mg kg sup(-1) (av. 1280.19 mg kg sup(-1)) and the salinity varied from 35.01 to 35.10 x 10 sup(-3) (av. 35.04 x 10 sup(-3)). The ratios of boron, calcium and magnesium to chlorinity in the lagoon water showed wide variation and were...

  18. The high resolution mapping of the Venice Lagoon tidal network

    Science.gov (United States)

    Madricardo, Fantina; Foglini, Federica; Kruss, Aleksandra; Bellafiore, Debora; Trincardi, Fabio

    2017-04-01

    One of the biggest challenges of the direct observation of the ocean is to achieve a high resolution mapping of its seafloor morphology and benthic habitats. So far, sonars have mapped just 0.05% of the ocean floor with less than ten-meter resolution. The recent efforts of the scientific community have been devoted towards the mapping of both Deep Ocean and very shallow coastal areas. Coastal and transitional environments in particular undergo strong morphological changes due to natural and anthropogenic pressure. Nowadays, only about 5% of the seafloor of these environments † have been mapped: the shallowness of these environments has prevented the use of underwater acoustics to reveal their morphological features. The recent technological development of multibeam echosounder systems, however, enables these instruments to achieve very high performances also in such shallow environments. In this work, we present results and case studies of an extensive multibeam survey carried out in the Lagoon of Venice in 2013. The Lagoon of Venice is the biggest lagoon in the Mediterranean Sea with a surface of about 550 km2 and with an average depth of about 1 m. In the last century, the morphological and ecological properties of the lagoon changed dramatically: the surface of the salt marshes was reduced by 60% and some parts of the lagoon are deepening with a net sediment flux exiting from the inlets. Moreover, major engineering interventions are currently ongoing at the inlets (MOSE project). These changes at the inlets could affect substantially the lagoon environment. To understand and monitor the future evolution of the Lagoon of Venice, ISMAR within the project RITMARE (a National Research Programme funded by the Italian Ministry of University and Research) carried out an extensive survey, involving a team of more than 25 scientists, to collect high resolution (0.5 m) bathymetry of key study areas such as the tidal inlets and channels. Following a broad

  19. Seasonal mercury transformation and surficial sediment detoxification by bacteria of Marano and Grado lagoons

    Science.gov (United States)

    Baldi, Franco; Gallo, Michele; Marchetto, Davide; Fani, Renato; Maida, Isabel; Horvat, Milena; Fajon, Vesna; Zizek, Suzana; Hines, Mark

    2012-11-01

    Marano and Grado lagoons are polluted by mercury from the Isonzo River and a chlor-alkali plant, yet despite this contamination, clam cultivation is one of the main activities in the region. Four stations (MA, MB, MC and GD) were chosen for clam seeding and surficial sediments were monitored in autumn, winter and summer to determine the Hg detoxifying role of bacteria. Biotransformation of Hg species in surficial sediments of Marano and Grado lagoons was investigated while taking into consideration the speciation of organic matter in the biochemical classes of PRT (proteins), CHO (carbohydrates) and LIP (lipids), water-washed cations and anions, bacterial biomass, Hg-resistant bacteria, some specific microbial activities such as sulfate reduction rates, Hg methylation rates, Hg-demethylation rates, and enzymatic ionic Hg reduction. MeHg in sediments was well correlated with PRT content, whereas total Hg in sediments correlated with numbers of Hg-resistant bacteria. Correlations of the latter with Hg-demethylation rates in autumn and winter suggested a direct role Hg-resistant bacteria in Hg detoxification by producing elemental Hg (Hg0) from ionic Hg and probably also from MeHg. MeHg-demethylation rates were ˜10 times higher than Hg methylation rates, were highest in summer and correlated with high sulfate reduction rates indicating that MeHg was probably degraded in summer by sulfate-reducing bacteria via an oxidative pathway. During the summer period, aerobic heterotrophic Hg-resistant bacteria decreased to <2% compared to 53% in winter. Four Hg-resistant bacterial strains were isolated, two Gram-positive (Staphylococcus and Bacillus) and two Gram-negative (Stenotrophomonas and Pseudomonas). Two were able to produce Hg0, but just one contained a merA gene; while other two strains did not produce Hg0 even though they were able to grow at 5 μg ml of HgCl2. Lagoon sediments support a strong sulfur cycle in summer that controls Hg methylation and demethylation

  20. Mapping of Affordance and Activity as the Biophilic Design Principle of Blue Lagoon Tourism Area Yogyakarta

    Directory of Open Access Journals (Sweden)

    Saptorini Hastuti

    2018-01-01

    Full Text Available Bathing and playing in the river is not a new phenomenon for some people. But this experience creates a recreational spirit on the Tepusriver which is now better known as the Blue Lagoon. This area is a term for the settlement that is split a piece of the river in the dusun Ndalem Ngemplak Sleman. Its tributaries are clear and blue, surrounded by some springs with natural bamboo groves and old trees that invite local and around communities for recreation. The local community has anticipated it by responding to the communities’ demands as well as the recreation area. Appear sporadically “warungs” and recreational activities follow-up though not yet grown in conceptual. This paper aims to study the map of affordance and activity of previous research findings and could be used to the biophilic design to afford the health, productivity, and wellbeing in the tourism area. The method is by synthesizing the previous research findings in 2016, some relevant urban design theories, and biophilic design principle. The conclusion is paid attention to two main principles. The first principle is maximizing the utilization of existing natural properties and the existing cultural skills into its development to nourish visitors both physically and psychologically. The second principle is the Government, and Non-Government Organizations (i.e., expertise, academics, universities, investors support, both policy and financially, in many sectors: tourism, environment, and infrastructure.

  1. Groundwater flow in the Venice lagoon and remediation of the Porto Marghera industrial area (Italy)

    Science.gov (United States)

    Beretta, Giovanni Pietro; Terrenghi, Jacopo

    2017-05-01

    This study aims to determine the groundwater flow in a large area of the Venice (northeast Italy) lagoon that is under great anthropogenic pressure, which is influencing the regional flow in the surficial aquifer (about 30 m depth). The area presents several elements that condition the groundwater flow: extraction by means of drainage pumps and wells; tidal fluctuation; impermeable barriers that define part of the coastline, rivers and artificial channels; precipitation; recharge, etc. All the elements were studied separately, and then they were brought together in a numerical groundwater flow model to estimate the impact of each one. Identification of the impact of each element will help to optimise the characteristics of the Porto Marghera remediation systems. Longstanding industrial activity has had a strong impact on the soil and groundwater quality, and expensive and complex emergency remediation measures in problematic locations have been undertaken to ensure the continuity of industrial and maritime activities. The land reclamation and remediation works withdraw 56-74% of the water budget, while recharge from the river accounts for about 21-48% of the input. Only 21-42% of groundwater in the modelled area is derived from natural recharge sources, untouched by human activity. The drop of the piezometric level due to the realization of the upgradient impermeable barrier can be counteracted with the reduction of the pumping rate of the remediation systems.

  2. University of Florida Advanced Technologies Campus Testbed

    Science.gov (United States)

    2017-09-21

    The University of Florida (UF) and its Transportation Institute (UFTI), the Florida Department of Transportation (FDOT) and the City of Gainesville (CoG) are cooperating to develop a smart transportation testbed on the University of Florida (UF) main...

  3. Polymorphic microsatellite DNA markers for the Florida manatee (Trichechus manatus latirostris)

    Science.gov (United States)

    Pause, K.C.; Nourisson, C.; Clark, A.; Kellogg, M.E.; Bonde, R.K.; McGuire, P.M.

    2007-01-01

    Florida manatees (Trichechus manatus latirostris) are marine mammals that inhabit the coastal waters and rivers of the southeastern USA, primarily Florida. Previous studies have shown that Florida manatees have low mitochondrial DNA variability, suggesting that nuclear DNA loci are necessary for discriminatory analyses. Here we report 10 polymorphic microsatellite loci with an average of 4.2 alleles per locus, and average heterozygosity of 50.1%. These loci have been developed for use in population studies, parentage assignment, and individual identification. ?? 2007 Blackwell Publishing Ltd.

  4. The evolution of the Lagoon of Venice as a paradigm of anthropogenic alteration of ecosystems: a palaeoenvironmental reconstruction through wide-area acoustic surveys and core sampling

    Science.gov (United States)

    Madricardo, Fantina; Donnici, Sandra

    2013-04-01

    rate of the natural channels ranging from 10 to 20 m/century with a filling rate between 0.5 and 2.5 mm/year. As a further result of this investigation, we found a general simplification of the morphologies over the centuries with a drastic reduction of the number of channels and salt marshes. This simplification can be explained by natural causes such as the general increase of the mean sea level, and by human activities such as artificial river diversion and inlet modifications causing a reduced sediment supply and a change of the hydrodynamics. Finally, we observed that this tendency accelerated dramatically in the last century as a consequence of the construction of a deep industrial canal, dredged between 1961 and 1969 to allow navigation of large containers. These results can contribute to planning effective environmental strategies for the Lagoon of Venice.

  5. FLORIDA TOWER FOOTPRINT EXPERIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    WATSON,T.B.; DIETZ, R.N.; WILKE, R.; HENDREY, G.; LEWIN, K.; NAGY, J.; LECLERC, M.

    2007-01-01

    The Florida Footprint experiments were a series of field programs in which perfluorocarbon tracers were released in different configurations centered on a flux tower to generate a data set that can be used to test transport and dispersion models. These models are used to determine the sources of the CO{sub 2} that cause the fluxes measured at eddy covariance towers. Experiments were conducted in a managed slash pine forest, 10 km northeast of Gainesville, Florida, in 2002, 2004, and 2006 and in atmospheric conditions that ranged from well mixed, to very stable, including the transition period between convective conditions at midday to stable conditions after sun set. There were a total of 15 experiments. The characteristics of the PFTs, details of sampling and analysis methods, quality control measures, and analytical statistics including confidence limits are presented. Details of the field programs including tracer release rates, tracer source configurations, and configuration of the samplers are discussed. The result of this experiment is a high quality, well documented tracer and meteorological data set that can be used to improve and validate canopy dispersion models.

  6. Toxicity of contaminants in lagoons and pannes of the Indiana Dunes National Lakeshore

    International Nuclear Information System (INIS)

    Gillespie, R.; Speelman, J.; Stewart, P.M.

    1995-01-01

    Contaminants in water and sediments of lagoons and pannes were 2--90 times greater at sites adjacent to slag and coal piles than those at reference sites. One site (Lagoon-US5) had sediments with very high concentrations of toxic organics (e.g. naphthalene, phenanthrene, dibenzofuran). Although analyses indicated a gradient of contaminant concentration with distance from their sources, toxicity assays were somewhat equivocal. With the exception of less reproduction in Ceriodaphnia at one lagoon site (US3 = 0.55 of reference), survival of fathead minnows and reproduction in Ceriodaphnia in lagoon and panne waters varied independently of the contaminant concentration. In fact, there was better Ceriodaphnia reproduction in water from two contaminated sites (Lagoon-US5, Panne-WP1) than in water from reference sites. Fathead minnow survival, Ceriodaphnia survival, Ceriodaphnia reproduction, amphipod survival, and amphipod growth varied among sites in toxicity assays with sediments, 100% mortality of fatheads at Lagoon-US5, 100% mortality of Ceriodaphnia at Lagoon-US3, and less survival of fathead minnows at Lagoon-US3 indicate possible toxicity from contaminants in sediments at these sites. Of all organisms and end-points tested, Ceriodaphnia survival seemed to be most closely associated with concentrations of contaminants in lagoon water and sediments. Amphipod survival also varied with contaminants in sediments, however, survival in sediments of contaminated sites ranged only from 0.90--0.93 of reference sites. Although the results are not consistent among organisms, toxicity assays indicate that sediments from the lagoon site with the highest contaminants (Lagoon-US5) and possibly those from another contaminated lagoon site (Lagoon-US3) could be toxic to aquatic organisms. Water and sediments from contaminated panne sites do not appear to be toxic to aquatic test organisms

  7. Alfred pilot wetland to treat municipal lagoon effluent - case study

    International Nuclear Information System (INIS)

    Crolla, A.; Kinsley, C.

    2002-01-01

    A constructed wetland demonstration system has been built to polish the municipal lagoon effluent from the village of Alfred. The treatment lagoons have an annual discharge in the spring and have currently reached maximum capacity; inhibiting further population growth or expansion of the local agri-food industries. The demonstration wetland system is designed to treat 15% of the municipal lagoon influent, that is, 155 m 3 /day or 23,250 m 3 /year. A three year monitoring program (2000-2002) was put in place to evaluate the wetland as a cost effective means to treat municipal lagoon wastewater for the village of Alfred. The 2000 and 2001 monitoring seasons have been completed, and the 2002 monitoring season will operate between June and October 2002. At the completion of the three year monitoring program the Alfred wetland system will be evaluated for its ability to polish the municipal lagoon effluent to meet the Spring/Summer/Fall discharge criteria, set by the Ontario Ministry of the Environment (MOE), for the receiving water body (Azatica Brook). As phosphorus is the most difficult element to remove down to MOE guidelines, the Alfred research wetland includes slag phosphorus adsorption filters and a vegetated filter as phosphorus polishing systems. Once the wetland system is approved by the MOE, the village of Alfred will be able to increase its capacity for municipal wastewater treatment. Constructed wetlands are still considered innovative systems in Ontario and government ministries (MOE, OMAFRA) are insisting upon 3-4 years of monitoring data for each constructed wetland system established. There is a clear need for monitoring data to be gathered on established systems, and for this data to be evaluated with the goal of developing reliable design guidelines. Ultimately this should result in having constructed wetlands recognised as viable wastewater treatment options in Ontario. With fewer grant programs for rural municipalities, cost effective systems such

  8. Gaining insight into Clipperton's lagoon hydrology using tritium

    International Nuclear Information System (INIS)

    Jean-Baptiste, P.; Fourre, E.; Charlou, J.L.; Donval, J.P.; Correge, T.

    2009-01-01

    Historical descriptions of the Clipperton lagoon appear to converge on the fact that it became isolated from the surrounding ocean around 1858. Since then, because of the high precipitation rate which largely exceeds evaporation in this region of the eastern tropical Pacific, a brackish lens has formed on top of the saline oceanic waters. In 1980, literature data show that the thickness of this water body was reaching 14 m. During the 2005 Etienne's Clipperton expedition, we collected lagoon water on two vertical profiles. Salinity, δ 18 O and tritium analyses were performed on these samples with the objective of gaining further insight into the lagoon hydrology and age of the deep waters. The upper 15 m were characterized by low salinities (5.4 ± 0.2), and δ 18 O and tritium values typical of local precipitation. At depth, waters had salinity and δ 18 O similar to oceanic surface waters but with low tritium concentrations, hence pointing to quite isolated waters representing a remnant of marine waters when the lagoon was still communicating with the ocean. At lagoon closure, the excess of precipitation over evaporation raised the lagoon level, thus creating a hydraulic pressure head which favored salt expulsion through the permeable walls of the atoll. A simple geohydrological modeling of this salt expulsion process based on Darcy's law describes reasonably well the time-evolution of the brackish lens. Tritium is used to discuss the main physical processes potentially involved in the slow ventilation of the halo-cline and deep saline layer, including vertical diffusion, sinking of salty Surface water intrusions and deep horizontal exchange through fissures in the limestone. These different mechanisms give reasonable results, which are all compatible with available salinity and isotopic data (δ 18 O and tritium), and therefore are all plausible candidates. Unfortunately, the lack of a detailed description of the vertical tritium profile in the halo

  9. Long-term changes of the phytoplankton community and biomass in the subtropical shallow Patos Lagoon Estuary, Brazil

    Science.gov (United States)

    Haraguchi, Lumi; Carstensen, Jacob; Abreu, Paulo Cesar; Odebrecht, Clarisse

    2015-09-01

    Seasonal and interannual changes (1993-2012) of water temperature and transparency, river discharge, salinity, water quality properties, chlorophyll a (chl-a) and the carbon biomass of the main taxonomical phytoplankton groups were evaluated at a shallow station (∼2 m) in the subtropical Patos Lagoon Estuary (PLE), Brazil. Large variations in salinity (0-35), due to a complex balance between Patos Lagoon outflow and oceanic inflows, affected significantly other water quality variables and phytoplankton dynamics, masking seasonal and interannual variability. Therefore, salinity effect was filtered out by means of a Generalized Additive Model (GAM). River discharge and salinity had a significant negative relation, with river discharge being highest and salinity lowest during July to October. Diatoms comprised the dominant phytoplankton group, contributing substantially to the seasonal cycle of chl-a showing higher values in austral spring/summer (September to April) and lowest in autumn/winter (May to August). PLE is a nutrient-rich estuary and the phytoplankton seasonal cycle was largely driven by light availability, with few exceptions in winter. Most variables exhibited large interannual variability. When varying salinity effect was accounted for, chl-a concentration and diatom biomass showed less irregularity over time, and significant increasing trends emerged for dinoflagellates and cyanobacteria. Long-term changes in phytoplankton and water quality were strongly related to variations in salinity, largely driven by freshwater discharge influenced by climatic variability, most pronounced for ENSO events. However, the significant increasing trend of the N:P ratio indicates that important environmental changes related to anthropogenic effects are undergoing, in addition to the hydrology in the PLE.

  10. Assessment of the metals concentration in sediments of Chimaliapan Lagoon, Lerma, Mexico State; Evaluacion de la concentracion de metales en sedimentos de la Laguna de Chimaliapan, Lerma, Estado de Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Perez V, I. A.

    2015-07-01

    The San Pedro Tultepec Lagoon of Quiroga in Lerma, known as Chimaliapan Lagoon is one of the Cienegas of the high course of the Lerma river. Considering that the lagoon is adjacent to an industrial area, have been altered the natural conditions of the channels, degrading the water quality and affecting the systems with different pollution sources, among which are industrial and municipal discharges and runoff of farmland. For this reason was decided to conduct a study in order to assess the concentration of metals in sediments of 4 sites and 4 downloads of the Chimaliapan Lagoon in order to infer the possible natural contributions and/or anthropogenic metals and their impact on both flora and fauna and the population that is supplied with the same, while assessing levels of enrichment of Ti, Cr, Mn, Fe, Cu, Zn and Pb metals as a result of contributions previously mentioned applying the technique of Energy Dispersive X-ray Fluorescence (EDXRF). According to the results by EDXRF, the sediments of the Lagoon assessed with the criterion of the EPA for the disposal of dredged sediments at this site, Mn and Fe only slightly exceed this criterion, then considering the Canadian criteria for the protection of aquatic life OMe, might have slight effects of Cr, Mn, Fe and Cu. Sediment discharges, evaluated with the same criteria indicate that Cr and Pb exceed the limit recommended by the EPA for the disposal of dredged sediments and Cr, Cu and Zn exceed the limit recommended for the protection of aquatic life OMe, noting that these metals may cause slight effects on organisms living in the Lagoon, such as carp and other organisms that live there, causing potential effects on humans through the food chain. (Author)

  11. Diet of the clupeid fish Platanichthys platana (Regan, 1917 in two different Brazilian coastal lagoons

    Directory of Open Access Journals (Sweden)

    Aguiaro Talita

    2003-01-01

    Full Text Available Platanichthys platana is considered a constant species in both Cabiúnas and Imboassica lagoons that are characterised by different marine and freshwater inputs, and anthropogenic influences. The stomach content analysis of P. platana captured between July 1991 and July 1993 revealed filamentous algae, detritus, eggs of benthic invertebrates, larvae of chironomids and bivalves as the main food sources in Imboassica lagoon. Small-sized cladocerans, copepods and shrimp larvae were the prevailing items in Cabiúnas lagoon. Seasonal food variations were noted for the fishes of Imboassica lagoon. Diet differences were highlighted within specimens lesser than 40 mm standard length in Imboassica lagoon, and were related to the increase of marine influence due to artificial sand barrier openings. Dissimilarities among size classes in relation to invertebrate larvae consumption were observed in fishes from Cabiúnas lagoon.

  12. Interaction between pesticides and humic substances from tropical coastal lagoons

    International Nuclear Information System (INIS)

    Gonzalez-Farias, F.; Carvalho, F.P.; Fowler, S.W.; Cotret, O.

    1999-01-01

    The HS that enter the lagoons with freshwater runoff tend to precipitate with salinity. Experiments were done in laboratory to determine the effect of HS (isolated from coastal lagoons) and humic acids (HA) (Aldrich) on the partition of selected pesticides between water and sediment phases. Due to the accurate results obtained with radio-labelled compounds, 14 C-labelled pesticides were used for the experiments. The selected pesticides were: chlorpyrifos (o,o-di-[1- 14 C]ethyl o-3,5,6-trichloro-2-pyridil phosphorotioate), DDT (1,1,1-trichloro-2,2-bis(p-chloro-[ring-U- 14 C]-phenyl)ethane) and parathion (o,o-diethyl o-4-nitro-[ring-U- 14 C]-phenyl phosphorotioate)

  13. Treatment of off-gas from lagoon sludge thermal decomposition

    International Nuclear Information System (INIS)

    Hwang, D. S.; Oh, J. H.; Choi, Y. D.; Hwang, S. T.; Park, J. H.; Ga, M. J.

    2005-01-01

    Korea Atomic Energy Research Institute (KAERI) has launched a decommissioning program of the uranium conversion plant in 2001. The treatment of the sludge waste, which was generated during the operation of the plant and stored in the lagoon, is one of the most important tasks in the decommissioning program of the plant. The major compounds of the lagoon sludge are ammonium nitrate, sodium nitrate, calcium nitrate, calcium carbonate, and uranium compounds. The minor compounds are iron, magnesium, aluminum, silicon and phosphorus. A treatment process of the sludge was developed as figure 1 based on the results of the sludge characteristics and the developed treatment technologies. A treatment of off-gas evolved from the nitrate salts thermal decomposition is one of the important process. Off-gas treatment by using a selective catalytic reduction (SCR) method was investigated in this study

  14. Very bright optical transient near the Trifid and Lagoon Nebulae

    Science.gov (United States)

    Dunsby, Peter

    2018-03-01

    Peter Dunsby (University of Cape Town) reports the detection of a very bright optical transient in the region between the Lagoon and Trifid Nebulae based on observations obtained from Cape Town on 20 March 2018, between 01:00 and 03:45 UT. The object was visible throughout the full duration of the observations and not seen when this field was observed previously (08 March 2018).

  15. Heavy-metal pollution assessment in the coastal lagoons of Jacarepaguá, Rio de Janeiro, Brazil.

    Science.gov (United States)

    Fernandes, H M; Bidone, E D; Veiga, L H; Patchineelam, S R

    1994-01-01

    The Jacarepaguá lagoon receives the waste from 239 industries and domestic sewage. Bottom sediment analysis revealed that metal pollution is not spread over the lagoons but restricted to the discharge areas of the main metal-carrier rivers. Metal concentrations in superficial water showed the following concentrations values in ng/ml: Zn, 9.63+/-3.59; Pb, 0.61+/-0.43; Cu, 0.94+/-0.45; Mn, 12.7+/-8.0. Metal concentration in fish (average of seven different species) presented the following results, in mg/kg wet weight: Cr, 0.08+/-0.01; Cu, 0.4+/-0.15; Zn, 4.6+/-3.4; Fe, 2.4+/-1.3; Mn, 0.4+/-0.3. These results imply, considering fish consumption rate and the RfD (USEPA Reference Dose), that the local population is not exposed to undue health risks. Metal concentrations in the water may, however, increase due to their dissolution induced by pH and redox changes in the sediments.

  16. Sedimentary records, reconstructing past trends in environmental changes and anthropogenic influences in the tropical lagoons of Tahiti and New Caledonia

    International Nuclear Information System (INIS)

    Fernandez, J.M.; Fichez, R.; Chifflet, S.; Bellet, S.; Badie, C.; Trescinski, M.; Harris, P.; Bernard, C.

    1998-01-01

    Full text: This work was designed to assess the ability of sediments to record past environmental changes in two lagoon systems of the South Pacific. Sediment cores were retrieved by SCUBA diving from Papeete Harbour (French Polynesia) and from the Bay of Dumbea (Noumea, New-Caledonia). The sediment was dated by measuring the decrease in the activity of excess 210 Pb. For each site a comparison is made between the evolution of geochemical tracer and the major events, including those related to human activity. As the research programme called for a large number of 210 Pb measurements, a microwave oven was used to enhance the efficiency of the radiochemical treatment of the samples (Polonium extraction). This decreased significantly the time required for sample preparation. In Papeete harbour, the building of a sea-wall on the barrier reef considerably reduced inputs of ocean water in this part of the lagoon. The corresponding modification in water circulation apparently produced major changes in the chemical behaviour of heavy metal. In Noumea, sediment records for the past 50 years tend to demonstrate that recent improved management of mining sites resulted in a significant decrease in the discharge of suspended solids by the Dumbea river

  17. Environmental Impact Analysis Process. Preliminary Environmental Constraints Survey U.S. Air Force, Space Division Advanced Launch System (ALS)

    Science.gov (United States)

    1988-09-01

    macroinvertebrates were collected from brackish lagoons surrounding Launch3 Complex 39A and the northern Banana River (NASA 1986). Many species of plants...East Coast 3 Surface water in the ETR includes portions of the Indian River, the Banana River, Mosquito Lagoon , and all of Banana Creek. These water...as shallow estuarine lagoons . In compliance with the Clean Water Act (CWA), surface waters have been classified by the State of Florida. Mosquito

  18. Metabolism and Gaseous Exchanges in Two Coastal Lagoons from Rio de Janeiro with Distinct Limnological Characteristics

    OpenAIRE

    Sidinei M. Thomaz; Alex Enrich-Prast; José F. Gonçalves Jr.; Anderson M. dos Santos; Francisco A. Esteves

    2001-01-01

    The global metabolism and exchange of gases with the atmosphere were measured during a diel cycle in two tropical coastal lagoons, using the curves of carbon dioxide and dissolved oxygen. Heterotrophic metabolism (net CO2 production and net O2 consumption) was observed in a black water lagoon (Comprida), and autotrophic metabolism (net O2 production and net CO2 consumption) in a clear water lagoon (Imboassica). These differences were attributed to the limnological characteristics of both ecos...

  19. Living benthic Foraminifera from the Saquarema lagoonal system (Rio de Janeiro, southeastern Brazil)

    OpenAIRE

    Belart, Pierre; Laut, Vanessa; Clemente, Iara; Raposo, Débora; Martins, Virgínia; Frontalini, Fabrizio; Lorini, Maria; Fortes, Rafael; Laut, Lazaro

    2017-01-01

    Transitional environments such as coastal lagoons with narrow connections to the sea are ecosystems very sensitive to natural or anthropogenic pressures. They are biodiversity hotspots and for this reason it should be studied and preserved. This study lists the benthic Foraminifera species from the Saquarema lagoonal system (SLS), Rio de Janeiro state, Brazil. This complex ecosystem consists of four large connected lagoons, namely Urussanga, Jardim, Boqueirão, and Saquarema. A poorly diversif...

  20. Bedrock neutralization study for the Bruin Lagoon Superfund Site

    International Nuclear Information System (INIS)

    Patelunas, G.M.; Lenhardt, D.R.; Niece, J.E.

    1989-01-01

    The Bruin Lagoon site is located in Bruin Butler County, Pennsylvania, and is listed as No. 3 on the U.S. Environmental Protection Agencies' National Priority List. The Lagoon contains waste petroleum tars, sulfuric acid, coal combustion ash, spent bauxite and other waste materials. This paper reports on the bedrock neutralization study, conducted to assess the feasibility of injecting caustic solutions into acid-contaminated bedrock beneath the lagoon. The site is underlain by a fine to medium grain quartz sandstone which is contaminated with acid to depths in excess of 30 feet. For this investigation, Nx-cores were obtained and pressure tests conducted to a depth of 30 feet below the top of rock. Leach tests were conducted on contaminated core sections using sodium hydroxide and sodium carbonate solutions. A total of 12 core sections were exposed in 3-inch diameter test cylinders and permeated under a positive pressure of 25 to 50 psi. Measurements of leachate volume, temperature, pH, and hydraulic conductivity were recorded

  1. Estimated discharge of treated wastewater in Florida, 1990

    Science.gov (United States)

    Marella, R.L.

    1994-01-01

    According to the Florida Department of Environ- mental Protection, 5,100 wastewater treatment systems were in operation during 1990. Of this total, 72 percent were domestic wastewater facilities and 28 percent were industrial waste- water facilities. The number of wastewater systems inventoried for 1990 was 1,062 (systems that treated and discharged more than 0.01 Mgal/d or had a plant capacity of greater than 0.04 Mgal/d. Based on this inventory, the estimated discharge of treated wastewater in Florida during 1990 totaled 1,638 million gallons per day. Approxi- mately 65 percent of this water was discharged to surface water during 1990 and the remaining 35 percent was discharged to ground water. Discharge to surface water includes effluent outfalls into the Atlantic Ocean (32 percent), while the re- maining (68 percent) is discharged into the Gulf of Mexico, bays, rivers, wetlands, and other surface water bodies throughout Florida. Discharge to ground-water includes treated effluent outfalls to land application systems (reuse systems and spray fields), drain fields, percolation ponds (51 percent), and to injection wells (49 percent). An estimated 322 million gallons per day of the treated domestic and industrial wastewater was reused during 1990. Discharge of treated domestic wastewater from the 994 systems inventoried in Florida during 1990 totaled 1,353 million gallons per day and served an estimated 8.58 million people (66 percent of the population of Florida in 1990). The remaining 34 percent of the popu- lation (4.36 million) are served by the 2,700 smaller domestic wastewater systems or have individual septic tanks. In 1990, there were 1.56 million septic tanks in Florida. Discharge of industrial wastewater was inventoried for 68 systems in 1990 and totaled 285 million gallons per day. Discharge of domestic wastewater in- creased more than 20 percent and industrial wastewater discharge increased 5 percent from 1985 to 1990. (USGS)

  2. Spatiotemporal variation of bacterial community composition and possible controlling factors in tropical shallow lagoons.

    Science.gov (United States)

    Laque, Thaís; Farjalla, Vinicius F; Rosado, Alexandre S; Esteves, Francisco A

    2010-05-01

    Bacterial community composition (BCC) has been extensively related to specific environmental conditions. Tropical coastal lagoons present great temporal and spatial variation in their limnological conditions, which, in turn, should influence the BCC. Here, we sought for the limnological factors that influence, in space and time, the BCC in tropical coastal lagoons (Rio de Janeiro State, Brazil). The Visgueiro lagoon was sampled monthly for 1 year and eight lagoons were sampled once for temporal and spatial analysis, respectively. BCC was evaluated by bacteria-specific PCR-DGGE methods. Great variations were observed in limnological conditions and BCC on both temporal and spatial scales. Changes in the BCC of Visgueiro lagoon throughout the year were best related to salinity and concentrations of NO (3) (-) , dissolved phosphorus and chlorophyll-a, while changes in BCC between lagoons were best related to salinity and dissolved phosphorus concentration. Salinity has a direct impact on the integrity of the bacterial cell, and it was previously observed that phosphorus is the main limiting nutrient to bacterial growth in these lagoons. Therefore, we conclude that great variations in limnological conditions of coastal lagoons throughout time and space resulted in different BCCs and salinity and nutrient concentration, particularly dissolved phosphorus, are the main limnological factors influencing BCC in these tropical coastal lagoons.

  3. Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation

    Energy Technology Data Exchange (ETDEWEB)

    McMurtry, G.M.; Schneider, R.C. (Hawaii Univ., Honolulu (USA). Hawaii Inst. of Geophysics); Colin, P.L. (Hawaii Inst. of Marine Biology, Honolulu (USA)); Buddemeier, R.W. (California Univ., Livermore (USA). Lawrence Livermore Lab.); Suchanek, T.H. (Fairleigh Dickinson Univ., St. Croix, Virgin Islands (USA). West Indies Lab.)

    1985-02-21

    The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. The authors report elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon.

  4. Numerical Survey of Contaminant Transport and Self-Cleansing of Water in Nador Lagoon, Morocco

    Directory of Open Access Journals (Sweden)

    E. M. Chaabelasri

    2014-01-01

    Full Text Available Numerical simulations are presented of the flow hydrodynamics and hypothetical contaminant dispersion patterns in Nador Lagoon, a shallow lagoon with a barrier island situated on the coast of Morocco. It is found that the natural circulation forced by the tidal flow in the lagoon is greatly affected by the development of an artificial inlet in the barrier island. The case study demonstrates the potential use of modern computational hydraulics as a tool integrated in the decision support system designed to manage a lagoon ecosystem.

  5. Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation

    International Nuclear Information System (INIS)

    McMurtry, G.M.; Schneider, R.C.; Buddemeier, R.W.; Suchanek, T.H.

    1985-01-01

    The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. The authors report elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon. (author)

  6. The effect of floods on sediment contamination in a microtidal coastal lagoon: the lagoon of Lesina, Italy.

    Science.gov (United States)

    D'Adamo, Raffaele; Specchiulli, Antonietta; Cassin, Daniele; Botter, Margherita; Zonta, Roberto; Fabbrocini, Adele

    2014-10-01

    The effects on the microtidal lagoon of Lesina of runoff and the discharge of water and material from agricultural activities were investigated combining chemical analyses of pollutants [11 metals and 16 priority polycyclic aromatic compounds (PAHs)], determination of organic matter and grain size, and performance of innovative ecotoxicological tests. For metals, enrichment factors >3 for arsenic, nickel, and copper (Cu) were observed in the eastern zone of the lagoon, which is affected by nearby urban activities with discharge of water and domestic waste and by agricultural input with waters rich in fertilizers. Cu was correlated with no other metal, and its high concentrations (≤77 µg g(-1)) may result from the use of Cu-based fungicides in vineyards. Total PAHs (2,230 ± 3,150 ng g(-1)) displayed a wide range of concentrations with hot spots near freshwater inputs from the part of the catchment area exploited for wheat crops. Pyrolitic contamination also emerged, with higher-mass PAH congeners, such as asphalt, bitumen or coal, usually present in higher fractions as the dominant components. Ecotoxicological evaluations recorded moderate to high toxicity levels; the innovative MOT test bioassay showed good discriminatory ability because it identified a lagoon area whose inputs mainly depend on agricultural activities and which is impacted by metals rather than PAHs. Floods during periods of heavy rain and the discharge of water and material from agricultural activities may impact vulnerable systems, such as the lagoon of Lesina, where the presence of hot spots with remarkably high pollution values was observed.

  7. Hydrogeologic controls on chemical transport at Malibu Lagoon, CA: Implications for land to sea exchange in coastal lagoon systems

    Directory of Open Access Journals (Sweden)

    N. Dimova

    2017-06-01

    New hydrological insights for the region: Nearshore lagoons that are seasonally disconnected from the coastal ocean occupy about 10% of coastal areas worldwide. Lagoon systems often are poorly flushed and thus sensitive to nutrient over-enrichment that can lead to eutrophication, oxygen depletion, and/or pervasive algal blooms. This sensitivity is exacerbated in lagoons that are intermittently closed to surface water exchange with the sea and occur in populous coastal areas. Such estuarine systems are disconnected from the sea during most of the year by wave-built barriers, but during the rainy season these berms can breach, enabling direct water exchange. Using naturally-occurring 222Rn as groundwater tracer, we estimate that groundwater discharge to Malibu Lagoon during open berm conditions was one order of magnitude higher (21 ± 17 cm/day than during closed berm conditions (1.8 ± 1.4 cm/day. The SGD (submarine groundwater discharge into nearshore coastal waters at the SurferRider and Colony Malibu was 4.2 cm/day on average. The exported total dissolved nitrogen (TDN through the berm during closed berm was 1.6 × 10−3 mol/day, whereas during open berm (exported by the Creek was 3.5 × 103 mol/day. Although these evaluations are specific to the collection campaigns the 2009 and 2010 hydro years, these two distinct hydrologic scenarios play an important role in the seasonality and geochemical impact of land/sea exchange, and highlight the sensitivity of such systems to future impacts such as sea level rise and increasing coastal populations.

  8. Seasonal steady-state budgets of nutrients and stoichiometric calculations in an Eastern Mediterranean lagoon (Papas Lagoon-Greece

    Directory of Open Access Journals (Sweden)

    E. KRASAKOPOULOU

    2011-01-01

    Full Text Available The Papas Lagoon is an enclosed, small shallow water body in western Greece. The lagoon is naturally affected by eutrophication phenomena, but occasionally during the summer season, dystrophic crises occur, related to the decomposition of large beds of macroalgae. Physicochemical data collected monthly, from June 1998 to September 1999, were compiled and coupled with historical meteorological data, in order to construct seasonal water, salt and nutrients budgets using a single box single layer LOICZ model. Nutrients and other hydrochemical parameters exhibit great spatial and temporal variations. The non-conservative dissolved inorganic phosphorus flux (ΔDIP is always positive, thus indicating that the system acts as a net source of DIP for the adjacent coastal waters. Higher values were estimated  uring summer and autumn, probably due to organic matter mineralisation and release of DIP from surficial sediments in the reduced environment. In contrast to the ΔDIP, the non-conservative balance of dissolved inorganic nitrogen (ΔDIN is negative for most of the year, except for the summer, indicating the dominance of DIN removal processes in the Papas Lagoon. The Ulva growth and decomposition processes seem likely to be of essential importance for the evaluation of the non-conservative DIN fluxes. During the investigated period the amount of organic carbon respired and mineralized is greater than that produced by gross photosynthesis and the Papas Lagoon is a net heterotrophic system. Losses of DIN via denitrification appear to dominate over its inputs through nitrogen fixation throughout the year.

  9. Fish community composition, seasonality and abundance in Fortaleza Lagoon, cidreira

    Directory of Open Access Journals (Sweden)

    Lúcia Cabral Schifino

    2004-09-01

    Full Text Available The Fortaleza Lagoon belongs to the Southern Tramandaí subsystem, formed by lagoons disposed linearly on the north-south direction (30º 08’S, 50º 13’W. The objective of this study was to describe some aspects related to the composition of the fish community of Fortaleza Lagoon. Samples were collected monthly from November 1998 to October 1999. The specimens were captured at four previously determined points in the lagoon, and classified in five orders, 12 families and 22 species. Cyphocharax voga, Hyphessobrycon luetkenii, Oligosarcus jenynsii, Oligosarcus robustus and Loricariichthys anus were more abundant species. Amongst the sampled species only two could not be characterised as freshwater species: Centropomus sp (marine and Lycengraulius grossidens (estuarine. The ichthyofauna of the lagoon was predominantly composed by constant species.A Planície Costeira do Rio Grande do Sul é formada por uma série de corpos d’água, dispostos em seqüência ao longo da costa. A lagoa da Fortaleza pertence ao subsistema lagunar Tramandaí-Sul que é composto por lagoas, dispostas linearmente no sentido norte-sul. O do presente estudo teve como objetivo descrever alguns aspectos relacionados à composição da comunidade de peixes da Lagoa da Fortaleza. As amostragens foram realizadas, mensalmente, no período de novembro de 1998 a outubro de 1999. Os exemplares foram capturados em 4 pontos da lagoa previamente determinados e classificados em 5 ordens, 11 famílias e 22 espécies. As espécies Cyphocharax voga, Hyphessobrycon luetkenii, Oligosarcus jenynsii, Oligosarcus robustus e Loricariichthys anus mostraram-se as mais abundantes. Entre as espécies coletadas apenas duas não caracterizam espécies de água doce: Centropomus sp (marinha and Lycengraulius grossidens (estuarina. A ictiofauna da lagoa caracterizou-se por uma predominância de espécies constantes.

  10. Depositional history and fault-related studies, Bolinas Lagoon, California

    Science.gov (United States)

    Berquist, Joel R.

    1978-01-01

    Studies of core sediments and seismic reflection profiles elucidate the structure and depositional history of Bolinas Lagoon, Calif., which covers 4.4 km 2 and lies in the San Andreas fault zone at the southeast corner of the Point Reyes Peninsula 20 km northwest of San Francisco. The 1906 trace of the San Andreas fault crosses the west side of the lagoon and was determined from (1) tectonically caused salt-marsh destruction indicated by comparison of 1854 and 1929 U.S. Coast and Geodetic Survey (U.S.C. & G.S.) topographic surveys, (2) formation of a tidal channel along the border of destroyed salt marshes, and (3) azimuths of the trend of the fault measured in 1907. Subsidence in the lagoon of 30 cm occurred east of the San Andreas fault in 1906. Near the east shore, seismic-reflection profiling indicates the existence of a graben fault that may connect to a graben fault on the Golden Gate Platform. Comparison of radiocarbon dates on shells and plant debris from boreholes drilled on Stinson Beach spit with a relative sea-level curve constructed for southern San Francisco Bay indicates 5.8 to more than 17.9 m of tectonic subsidence of sediments now located 33 m below mean sea level. Cored sediments indicate a marine transgression dated at 7770?65 yrs B.P. overlying freshwater organic-rich lake deposits. Fossil pollen including 2 to 8 percent Picea (spruce) indicate a late Pleistocene (?)-Early Holocene climate, cooler, wetter, and foggier than at present. Above the transgression are discontinuous and interfingering sequences of transgressive-regressive marine, estuarine, and barrier sediments that reflect rapid lateral and vertical shifts of successive depositional environments. Fossil megafauna indicate (1) accumulation in a protected, shallow-water estuary or bay, and (2) that the lagoon was probably continuously shallow and never a deep-water embayment. Analysis of grain-size parameters, pollen frequencies, and organic remains from a core near the north end of

  11. Study of organic sulphur compounds (DMS, DMSP and CS2) in lagoon ecosystems: the case of the Venice lagoon.

    Science.gov (United States)

    Gambaro, Andrea; Moret, Ivo; Piazza, Rossano; Andreoli, Carlo; Corami, Fabiana; Turetta, Clara; Cescon, Paolo

    2003-03-01

    This study of the origin and fate of dimethyl sulphide (DMS) in a particular and complex lagoon ecosystem such as that of the Venice lagoon focuses on the temporal evolutions of DMS concentrations in surface water together with those of dimethylsulphoniopropionate (DMSP), carbon disulphide (CS2), nutrients (nitrate, nitrite, ammonium, phosphate, silicate), sulphate, chlorophyll a, chlorinity, water temperature and phytoplankton (composition and density). Measurements were made from 3 March 1997 to 23 July 1998 at three stations in the central part of the Venice lagoon. The temporal trends of DMS concentration showed an absolute maximum concentration in winter (65 nmol S/l, 19/2/1998, Stn. 1; 119 nmol S/l, 19/2/1998, Stn. 2; 29 nmol S/l, 17/2/1998, Stn. 3) and two relative maxima in the spring-summer period. The spring-summer secondary maxima of DMS concentration were related to the maxima of DMSP and chlorophyll a concentrations and consequently to phytoplanktonic abundance while the winter DMS maximum showed no relation to DMSP or to chlorophyll a suggesting that the production and the fate of DMS could be different for the two periods. According to previous studies the CS2 concentration increased in the spring, achieved its maximum in summer, decreased in autumn and fell to its minimum in winter.

  12. Groundwater and porewater as major sources of alkalinity to a fringing coral reef lagoon (Muri Lagoon, Cook Islands

    Directory of Open Access Journals (Sweden)

    T. Cyronak

    2013-04-01

    Full Text Available To better predict how ocean acidification will affect coral reefs, it is important to understand how biogeochemical cycles on reefs alter carbonate chemistry over various temporal and spatial scales. This study quantifies the contribution of shallow porewater exchange (as quantified from advective chamber incubations and fresh groundwater discharge (as traced by 222Rn to total alkalinity (TA dynamics on a fringing coral reef lagoon along the southern Pacific island of Rarotonga over a tidal and diel cycle. Benthic alkalinity fluxes were affected by the advective circulation of water through permeable sediments, with net daily flux rates of carbonate alkalinity ranging from −1.55 to 7.76 mmol m−2 d−1, depending on the advection rate. Submarine groundwater discharge (SGD was a source of TA to the lagoon, with the highest flux rates measured at low tide, and an average daily TA flux of 1080 mmol m−2 d−1 at the sampling site. Both sources of TA were important on a reef-wide basis, although SGD acted solely as a delivery mechanism of TA to the lagoon, while porewater advection was either a sink or source of TA dependent on the time of day. This study describes overlooked sources of TA to coral reef ecosystems that can potentially alter water column carbonate chemistry. We suggest that porewater and groundwater fluxes of TA should be taken into account in ocean acidification models in order to properly address changing carbonate chemistry within coral reef ecosystems.

  13. Multi-annual and seasonal patterns of waterbird assemblages in a Mediterranean coastal lagoon (El Mellah lagoon of Northeastern Algeria

    Directory of Open Access Journals (Sweden)

    Telailia Salah

    2017-06-01

    Full Text Available Recently, Mediterranean coastal lagoons have raised considerable environmental concerns. Long-term studies of seasonal changes in waterbird assemblages are therefore extremely important in terms of ecological relevance and conservation of these sensitive ecosystems. An ornithological survey of four years was carried out in a typical costal wetland (El Mellah lagoon of Northeastern Algeria. Intra-seasonal comparison of waterbird assemblages (diversity indices demonstrates clear changes between the wintering and the breeding periods. It seems that the first one was rich in term of species number than the second season (43 against 24. In contrast, the breeding seasons were more equilibrate (high values of Simpson, Shannon and evenness index. Additionally, curves in the diversity/dominance diagram revealed that both wintering and breeding assemblages share the same characteristics of community structure, few dominant species (with intermediate relative abundance and many rare species with the relative abundance lower than 0.1. Invertebrates (25 species and piscivorous (11 species are the most abundant guilds over the four years of study (no significant differences among years have been calculated. The marked decline in bird species diversity recorded in this study (in comparison with previous studies is mainly due to salinity oscillations (due to aquaculture activities and may be of concern to wetland managers and it might be useful to provide some guidelines about the characteristics that coastal lagoons have to follow in the construction process to enhance the biodiversity.

  14. Spaceport Florida Authority: Business Plan

    Science.gov (United States)

    1996-01-01

    The Spaceport Florida Authority (SFA) was established under Florida Statute by the Governor and Legislature to assist the development of our nation's space transportation industry and to generate new space-related jobs, investment and opportunities statewide. Included in the Authorities' business plan is the statement of work and list of team members involved in creating the report, SFA's current operating concept, market analysis, assessment of accomplishments, a sample operating concept and a "roadmap to success".

  15. Regulation of bacterioplankton density and biomass in tropical shallow coastal lagoons

    Directory of Open Access Journals (Sweden)

    Fabiana MacCord

    Full Text Available AIM: Estimating bacterioplankton density and biomass and their regulating factors is important in order to evaluate aquatic systems' carrying capacity, regarding bacterial growth and the stock of matter in the bacterial community, which can be consumed by higher trophic levels. We aim to evaluate the limnological factors which regulate - in space and time - the bacterioplankton dynamics (abundance and biomass in five tropical coastal lagoons in the state of Rio de Janeiro, Brazil. METHOD: The current study was carried out at the following lagoons: Imboassica, Cabiúnas, Comprida, Carapebus and Garças. They differ in morphology and in their main limnological factors. The limnological variables as well as bacterioplankton abundance and biomass were monthly sampled for 14 months. Model selection analyses were performed in order to evaluate the main variables regulating the bacterioplankton's dynamics in these lagoons. RESULT: The salt concentration and the "space" factor (i.e. different lagoons explained great part of the bacterial density and biomass variance in the studied tropical coastal lagoons. When the lagoons were analyzed separately, salinity still explained great part of the variation of bacterial density and biomass in the Imboassica and Garças lagoons. On the other hand, phosphorus concentration was the main factor explaining the variance of bacterial density and biomass in the distrophic Cabiúnas, Comprida and Carapebus lagoons. There was a strong correlation between bacterial density and biomass (r² = 0.70, p < 0.05, indicating that bacterial biomass variations are highly dependent on bacterial density variations. CONCLUSION: (i Different limnological variables regulate the bacterial density and biomass in the studied coastal lagoons, (ii salt and phosphorus concentrations greatly explained the variation of bacterial density and biomass in the saline and distrophic lagoons, respectively, and (iii N-nitrate and chlorophyll

  16. Hydrology and Salt Balance in a Large, Hypersaline Coastal Lagoon: Lagoa de Araruama, Brazil

    Science.gov (United States)

    Kjerfve, Björn; Schettini, C. A. F.; Knoppers, Bastiaan; Lessa, Guilherme; Ferreira, H. O.

    1996-06-01

    Lagoa de Araruama in the state of Rio de Janeiro, Brazil, is a hypersaline coastal lagoon as a result of semi-arid climate conditions, a small drainage basin and a choked entrance channel. The lagoon has been continuously hypersaline for at least 4·5 centuries, but the mean salinity has varied substantially. It has recently decreased from 57 to 52 as indicated by density (salinity) measurements between 1965 and 1990. Analysis of more than 20 years of salinity time series data, in addition to monthly lagoon cruises to measure the spatial salinity distribution, indicate that the lagoon salinity largely fluctuates in response to the difference between evaporation and precipitation. The major factor explaining the long-term trend of decreasing salinity in the lagoon is the constant pumping of 1 m 3s -1of freshwater to the communities surrounding the lagoon from an adjacent watershed, and subsequent discharge of this water into Lagoa de Araruama. The net salt budget is primarily a balance between the advective import of salt from the coastal ocean and eddy diffusive export of salt to the ocean, although the extensive mining of salt from the lagoon during past decades is also a small but significant contribution to the salt budget. The flushing half-life is proposed as a useful time scale of water exchange, is calculated based on a combination of hydrological and tidal processes, and is excellent for comparison of lagoons and assessing water quality changes. The flushing half-life measures 83·5 days for Lagoa de Araruama, considerably longer than for most other coastal lagoons. The proposed dredging of a second ocean channel to Lagoa de Araruama is probably not a good idea. It is likely to accelerate the decrease of lagoon salinity and somewhat improve the lagoon water exchange. At the same time, this will eliminate the apparent buffering capacity provided by the hypersaline environment, and thus may potentially cause water quality problems.

  17. Stream-aquifer relations and the potentiometric surface of the Upper Floridan aquifer in the lower Apalachicola-Chattahoochee-Flint River basin in parts of Georgia, Florida, and Alabama, 1999-2000

    Science.gov (United States)

    Mosner, Melinda S.

    2002-01-01

    The Upper Floridan aquifer is the principal source of water for domestic and agricultural use in the lower Apalachicola-Chattahoochee-Flint (ACF) River Basin. Recent drought and increased water use have made understanding surface- and ground-water relations a priority for water-resource managers in the region. From July 1999 through August 2000, less than normal precipitation reduced streamflow in the area to less than 12 percent of average mean-daily streamflow and ground-water levels reached record or near-record lows. Effects of drought on stream-aquifer interactions in the basin were evaluated using baseflow estimation, ground-water seepage calculations, and potentiometric-surface maps. Ground-water discharge to streams, or baseflow, was estimated using three methods: field measurements, hydrograph separation, and linear regression analysis. Results were evaluated seasonally -- October 1999, April 2000, and August 2000 -- and for the period of record at four surface-water stations located on Kinchafoonee, Spring, Muckalee, and Turkey Creeks. Estimates of baseflow also were compared annually; ground-water discharge during the drought years, 1999 - 2000, was compared with ground-water discharge during a relatively wet year, 1994. Hydrograph separation indicated decreased base-flow of streams as the water level in the Upper Floridan aquifer declined. Mean-annual baseflow for Kinchafoonee, Spring, Muckalee, and Turkey Creeks ranged from 36 to 71 percent of total streamflow during the period of record. In 1994 baseflow accounted for only 37 to 56 percent of total streamflow, in 1999 baseflow comprised from 60 to 73 percent of total streamflow, and in 2000 baseflow comprised from 56 to 76 percent of streamflow. The percentage of total streamflow attributed to ground water increased during the drought, whereas other components of streamflow decreased (overland flow, interflow, and channel precipitation). Even though relative ground-water contributions were increased

  18. Andrew spares Florida Coast

    Science.gov (United States)

    Bush, Susan

    When geologists heard of the intensity of Hurricane Andrew, which struck the Florida coast on August 25 and then moved on to southern Louisiana, they were expecting the same kinds of coastal damage that Hurricane Hugo brought to the Caribbean and Carolina shores in 1989. Both storms were category 4 hurricanes, having winds of 131-155 mph and surges of 13-18 feet. However, the coastal damage never materialized, leaving geologists to analyze the factors that lessened the impact of the storm. “For minimum coastal damage, you couldn't have designed a better storm,” said Orrin Pilkey, director of the Program for the Study of Developed Shorelines (PSDS) in Durham, N.C. This was due in part to the nature of the storm itself and where it hit land, and in part to the regional geology, said Rob Thieler of PSDS. Despite the huge amounts of damage to buildings, there was virtually no evidence of coastal process destruction, he said.

  19. Recent sedimentary history of organic matter and nutrient accumulation in the Ohuira Lagoon, northwestern Mexico.

    Science.gov (United States)

    Ruiz-Fernández, Ana Carolina; Frignani, Mauro; Tesi, Tommaso; Bojórquez-Leyva, Humberto; Bellucci, Luca Giorgio; Páez-Osuna, Federico

    2007-08-01

    (210)Pb-derived sediment accumulation rates, as well as a suite of geochemical proxies (Al, Fe, delta(13)C, delta(15)N), were used to assess the time-dependent variations of C, N, and P fluxes recorded in two sediment cores collected at Ohuira Lagoon, in the Gulf of California, Mexico, during the last 100 years. Sedimentary C, N, and P concentrations increased with time and were related to land clearing, water impoundment, and agriculture practices, such as fertilization. C:N:P ratios and delta(13)C suggested an estuarine system that is responsive to increased C loading from a N-limited phytoplankton community, whereas delta(15)N values showed the transition between an estuarine-terrestrial to an estuarine-more marine environment, as a consequence of the declining freshwater supply into the estuary due to the channeling and impoundment of El Fuerte River between 1900 and 1956. The recent increases in nutrient fluxes (2- to 9-fold the pre-anthropogenic fluxes of C and N, and 2 to 13 times for P) taking place in the mainland from the 1940s, were related to the expansion of the intensive agriculture fields and to the more recent development of shrimp farming activities.

  20. Hexachlorocyclohexanes, Cyclodiene, Methoxychlor, and Heptachlor in Sediment of the Alvarado Lagoon System in Veracruz, Mexico

    Directory of Open Access Journals (Sweden)

    María del Refugio Castañeda-Chávez

    2018-01-01

    Full Text Available Organochlorine pesticides are used in agricultural areas and health campaigns, which reach the coastal environment through rivers, drains, runoffs, and atmospheric transport. In aquatic environments, they are adsorbed by particles of organic matter, depositing themselves in sediments in the bottom of these bodies, in which benthic organisms of commercial interest for human consumption inhabit. The objective of this research was to evaluate the concentration of organochlorine pesticides in sediment from the Alvarado lagoon system in Veracruz, Mexico. In 20 out of 41 sampling sites analyzed, 11 banned organochlorine pesticides were identified, such as hexachlorocyclohexane (HCH, lindane, aldrin, dieldrin, and endrin. The highest concentrations were as follows: aldrin: 46.05 ng g−1; β-HCH: 42.11 ng g−1; α-HCH: 38.44 ng g−1; gamma γ-HCH (lindane: 34.20 ng g−1; δ-HCH: 31.61 ng g−1; methoxychlor: 29.40 ng g−1; heptachlor epoxide: 25.70 ng g−1; heptachlor: 24.11 ng g−1; dieldrin: 22.13 ng g−1; endrin: 21.23 ng g−1; endrin aldehyde: 12.40 ng g−1. Concentrations reported are prohibited in international standards. There is a strong need to further evaluate, with scientific studies, the level of concentration reported by impact of compounds widely used in agricultural livestock activities.

  1. Length-weight relationship of fishes from coral reefs and lagoons of New Caledonia: an update

    OpenAIRE

    Letourneur, Y.; Kulbicki, M.; Labrosse, P.

    1998-01-01

    Length-weight relationships of 316 reef and lagoon fish from New Caledonia (SW Pacific Ocean) belonging to 68 families are computed. A total of 43,750 individuals was used for this purpose. Fish were sampled by different techniques such as rotenone poisoning, handline and bottom longline fishing, gill and trammel nets, and trawling in various isotopes (coral reefs, lagoon bottoms and mangroves).

  2. Plankton community dynamics in a subtropical lagoonal system and related factors

    Directory of Open Access Journals (Sweden)

    LETÍCIA DONADEL

    2016-03-01

    Full Text Available ABSTRACT Changes of the plankton community in a shallow, subtropical lagoonal system and its relation to environmental conditions were investigated during an annual cycle to provide information on its spatial and seasonal variation pattern. The study carried out at four sites (three in the Peixe lagoon and one in the Ruivo lagoon, which are located in the Lagoa do Peixe National Park, southern Brazil. The system has a temporary connection to the Atlantic Ocean by a narrow channel. The phytoplankton density was higher in the Peixe lagoon whereas the specific richness was higher in the Ruivo lagoon which is also a site with the lower salinity. The phytoplankton biomass near the channel showed seasonal variation with the highest value in fall and lowest in winter. Zooplankton richness was inversely correlated with salinity, and had the highest values in the Ruivo lagoon. Ordination analysis indicated seasonal and spatial patterns in plankton community in this lagoonal system, related to variation in salinity. In addition, the wind action and precipitation were important factors on the spatial and seasonal salinity changes in the lagoon with direct influence on the plankton community dynamics.

  3. Water quality characteristics at the estuary of Korle Lagoon in Ghana ...

    African Journals Online (AJOL)

    The Korle lagoon is a major run-off water receptacle and outlet from the city of Accra into the Gulf of Guinea. Uncontrolled discharges of domestic wastes and industrial effluents as well as raw sewage (which are washed into the lagoon during high tides), have led to its environment being seriously degraded.

  4. Sludge reduction and water quality improvement in anaerobic lagoons through influent pre-treatment

    Science.gov (United States)

    Confined swine production generates large volumes of wastewater typically stored and treated in anaerobic lagoons. These lagoons may require cleanup and closure measures in the future. In practice, liquid and sludge need to be removed by pumping, usually at great expense of energy, and land applied ...

  5. The Defense Committees of Sleepy Lagoon: A Convergent Struggle against Fascism, 1942-1944

    Science.gov (United States)

    Barajas, Frank P.

    2006-01-01

    The Sleepy Lagoon Defense Committee originated as an ad hoc committee and evolved to a broad-based movement for legal justice on behalf of seventeen youth convicted of murder and assault charges in connection with the Sleepy Lagoon case in Los Angeles in January 1943. This essay chronicles the multidimensional organizing to shift public opinion in…

  6. Production and zooplankton community structure in the lagoon and surrounding sea at Kavaratti atoll (Lakshadweep)

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, S.C.

    Higher values for the environmental parameters were generally obtained for the lagoon stations. Average values of pH, temperature, salinity, dissolved oxygen and phosphate-phosphorus, nitrate-nitrogen, silicate and silicon in the lagoon were 7.5, 31...

  7. Beach Ridge and Lagoon Systems as Indicator of Sea-Level Changes

    DEFF Research Database (Denmark)

    Sander, Lasse

    . This highstand period ended abruptly around 3.5 kyr BP with a marked RSL fall of approx. 1.3 m. In the lagoonal environments, facies transitions from organic-rich marine mud to marine sand are interpreted as winnowing lags resulting from a lowering of the wave-base. In a fossil lagoon system, the sand yields...

  8. Identifying tsunami deposits using shell taphonomy: Sur lagoon, Oman

    Science.gov (United States)

    Donato, S.; Reinhardt, E.; Rothaus, R.; Boyce, J.

    2007-05-01

    On November 28th, 1945 an 8.1 magnitude earthquake focused in the eastern portion of the Makran subduction zone (Arabian Sea) generated a powerful tsunami that destroyed many coastal villages in Pakistan and India. Reports indicate that the tsunami also caused significant damage in Muscat, Oman, although its effects elsewhere in Oman are unknown. A thick bivalve dominated shell horizon was discovered inside the Sur lagoon, which is located on the eastern promontory of Oman (200 km south of Muscat). This shell deposit is significant because it is laterally extensive (> 1 km2), extends deep within the lagoon (>2 km), ranges in thickness from 5 - 25 cm at the sample localities, contains numerous subtidal and offshore bivalve species, and articulated subtidal and offshore bivalve species are abundant. Although there is an absence of typical tsunami indicators such as allochthonous sediment in and around the lagoon, verbal accounts, cultural evidence recovered during coring, and the absence of strong storms during the past 100 years indicates that this shell unit was caused by the 1945 tsunami. In this setting, it would be advantageous to have another proxy for tsunami detection and risk prediction. The use of shell taphonomy is one of the potential indicators and here we present new evidence of its utility. We sampled this unit in eight locations, and compared the shell taphonomy to surface shell samples collected from beach and reworked horizons in the lagoon, and to shell samples from a known tsunami and corresponding storm/ballast deposit in Israel (Reinhardt et al., 2006). Taphonomic analysis yielded promising results, as the two tsunami horizons shared excellent agreement between the amount of fragmented shells, and the percentage of shells displaying angular breaks. Both of these categories were significantly different from the percentage of fragments and angular fragments recovered from the reworked, beach, and storm/ballast deposits, indicating different

  9. Simulated Effects of Seasonal Ground-Water Pumpage for Irrigation on Hydrologic Conditions in the Lower Apalachicola-Chattahoochee-Flint River Basin, Southwestern Georgia and Parts of Alabama and Florida, 1999-2002

    Science.gov (United States)

    Jones, L. Elliott; Torak, Lynn J.

    2006-01-01

    To determine the effects of seasonal ground-water pumpage for irrigation, a finite-element ground-water flow model was developed for the Upper Floridan aquifer in the lower Flint River Basin area, including adjacent parts of the Chattahoochee and Apalachicola River Basins. The model simulates withdrawal from the aquifer at 3,280 irrigation, municipal, and industrial wells; stream-aquifer flow between the aquifer and 36 area streams; leakage to and from the overlying upper semiconfining unit; regional ground-water flow at the lateral boundaries of the model; and water-table recharge in areas where the aquifer is at or near land surface. Steady-state calibration to drought conditions of October 1999 indicated that the model could adequately simulate measured groundwater levels at 275 well locations and streamflow gains and losses along 53 reaches of area streams. A transient simulation having 12 monthly stress periods from March 2001 to February 2002 incorporated time-varying stress from irrigation pumpage, stream and lake stage, head in the overlying upper semiconfining unit, and infiltration rates. Analysis of simulated water budgets of the Upper Floridan aquifer provides estimates of the source of water pumped for irrigation. During October 1999, an estimated 127 million gallons per day (Mgal/d) of irrigation pumpage from the Upper Floridan aquifer in the model area were simulated to be derived from changes in: stream-aquifer flux (about 56 Mgal/d, or 44 percent); leakage to or from the upper semiconfining unit (about 49 Mgal/d, or 39 percent); regional flow (about 18 Mgal/d, or 14 percent); leakage to or from Lakes Seminole and Blackshear (about 2.7 Mgal/d, or 2 percent); and flux at the Upper Floridan aquifer updip boundary (about 1.8 Mgal/d, or 1 percent). During the 2001 growing season (May-August), estimated irrigation pumpage ranged from about 310 to 830 Mgal/ d, about 79 percent of the 12-month total. During the growing season, irrigation pumpage was

  10. Venice, the city and the lagoon: a lost relationship?

    Directory of Open Access Journals (Sweden)

    Piero Pedrocco

    2014-01-01

    Full Text Available In June 2011, the Venetians Engineers organized a conference entitled: The Eighth district. The Laguna as a connection matrix. In a world where the concept of “city”, which has become improper, applies to so-called historical centers that increasingly large conurbations, much of the Laguna is peripheral space, where inedited stories and resonant events living with full-blown environmental degradation and decay culture, make it a place of margin. Today, the lagoon and coastal areas are a continuous with the water spaces and islands that separate them, facing with unfinished waterfront towards brackish non-places. In this context, the debates and choices around the Laguna alternate without a unified design. Venice is always less connected with the surroundings by water, and the water itself become a limit to mobility, where, on the contrary, it was the element that guaranteed it.In the renewed debate on development strategies, realized the MOSE, it will be asked for which city it has been made. The conference drew attention to the rediscovery of the central role of the Lagoon. Between local development and global challenges, including heritage and environmental protection. Is it possible to envisage a revitalization of the lagoon system as a matrix of physical and cultural connection? Which opportunities are offered today to the city of Venice to rediscover its amphibious and cosmopolitan size and discover the Laguna as an Eighth District? A place of sites for residence, recreation, work, in a renovated urban dimension across the board, opened towards the spaces of the islands.

  11. 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

  12. Temporal pattern in the bloom-forming macroalgae Chaetomorpha linum and Ulva pertusa in seagrass beds, Swan Lake lagoon, North China

    International Nuclear Information System (INIS)

    Zhang, Xiaomei; Zhou, Yi; Liu, Peng; Wang, Feng; Liu, Bingjian; Liu, Xujia; Xu, Qiang; Yang, Hongsheng

    2014-01-01

    Highlights: • We conducted an annual survey of bloom-forming macroalgae in a lagoon. • C. linum biomass reached 1712 ± 780 g DW m −2 at the northern part of the lagoon. • Macroalgae δ 15 N values indicated a land-based source of N enrichment to the blooms. • High nutrient concentrations near the river mouth supported the blooms. • C. linum blooms induced the loss of seagrasses and benthic filter feeders. - Abstract: Seagrasses that are distributed over a large area of the Swan Lake, Weihai, China, support a productive ecosystem. In recent years, however, frequent macroalgal blooms have changed the ecosystem structure and threatened the seagrasses. To understand the bloom-forming macroalgae we conducted a yearly field survey of Swan Lake. Results indicated that the macroalgae Chaetomorpha linum and Ulva pertusa both exhibited a much higher productivity and attained a greater maximum biomass (of 1712 ± 780 g DW m −2 and 1511 ± 555 g DW m −2 , respectively) than was the case for the seagrasses. The mean annual atomic ratios of C/N, C/P and N/P in C. linum were 14.31 ± 4.45, 402.82 ± 130.25, and 28.12 ± 2.08, respectively. The δ 15 N values (11.09 ± 0.91‰ for C. linum; 9.27 ± 2.83‰ for U. pertusa) indicated a land-based source of N enrichment to the macroalgal blooms. High concentrations of nitrogen and phosphorus in the lagoon, particularly near the river mouth, supported the blooms

  13. The role of benthic macrophytes and their associated macroinvertebrate community in coastal lagoon resistance to eutrophication.

    Science.gov (United States)

    Lloret, Javier; Marín, Arnaldo

    2009-12-01

    Eutrophication is widely recognised as one of the major menaces to coastal environments, particularly enclosed bays and lagoons. Although there is a general understanding of the consequences of eutrophication in these systems, there is a lack of sufficient knowledge concerning biotic feedbacks that influence eutrophication patterns and the resistance capacity of coastal environments. In this paper, the isotope ratios of main producers and consumers of a Mediterranean lagoon were examined in order to elucidate the fate of anthropogenic inputs from the main watercourse flowing into the lagoon. The results of the study of stable isotope data in the Mar Menor lagoon reflected that the whole benthic community plays an important role as a natural 'filter' that removes excess nutrients from the water column and stores them in the sediments, thereby enhancing lagoon resistance to eutrophication.

  14. The role of benthic macrophytes and their associated macroinvertebrate community in coastal lagoon resistance to eutrophication

    International Nuclear Information System (INIS)

    Lloret, Javier; Marin, Arnaldo

    2009-01-01

    Eutrophication is widely recognised as one of the major menaces to coastal environments, particularly enclosed bays and lagoons. Although there is a general understanding of the consequences of eutrophication in these systems, there is a lack of sufficient knowledge concerning biotic feedbacks that influence eutrophication patterns and the resistance capacity of coastal environments. In this paper, the isotope ratios of main producers and consumers of a Mediterranean lagoon were examined in order to elucidate the fate of anthropogenic inputs from the main watercourse flowing into the lagoon. The results of the study of stable isotope data in the Mar Menor lagoon reflected that the whole benthic community plays an important role as a natural 'filter' that removes excess nutrients from the water column and stores them in the sediments, thereby enhancing lagoon resistance to eutrophication.

  15. Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation.

    Science.gov (United States)

    McMurtry, G M; Schneider, R C; Colin, P L; Buddemeier, R W; Suchanek, T H

    The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. Studies of the burial of fallout radionuclides have been conducted on the islands and in several of the large craters, but studies of their vertical distribution have been limited to about the upper 20 cm of the lagoon sediments. We have found elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon.

  16. The Lagoon of Venice : the result of both natural factors and human influence

    Directory of Open Access Journals (Sweden)

    Oscar RAVERA

    2000-02-01

    Full Text Available This paper aims to present a picture of the lagoon of Venice and analyze the combined effects of natural factors and human influence on this fragile ecotone. The structure, functioning and evolution of the lagoon are illustrated. Under natural conditions, the solid load from the tributaries would transform the lagoon into dry land or, if the violence of the sea exceeded the solid load from the watershed, the lagoon would evolve into a marine bay. This natural succession has been hindered by the works undertaken by the Republic of Venice uninterruptedly through the centuries, because the lagoon environment was essential to the life and power of Venice. The effects of human activities from the beginning of the Venetian Republic to the present are described. In addition, the influence of socio-economic development on the lagoon area and, particularly, the impact of intensive agriculture and industrialization are discussed. A possible effect of eutrophication was the dramatic proliferation of the opportunistic macroalga Ulva rigida, which for about a decade played an important role in the physical, chemical and biological characteristics of the lagoon. At present, the most crucial problems of Venice and its lagoon are: the lowering of the level of the city in relation to that of the sea, the continuous decline in the number of inhabitants, the increasing frequency of the “high water” phenomenon, air and water pollution, and the increased erosion and salinity of the lagoon. The recent measures taken and those still to be applied for conserving and recovering Venice and its lagoon and, particularly, the works for preventing the risk of high water are compared. There is an evident need for a new type of socio-economic development in symbiosis with the environment and tradition of Venice.

  17. Epidemiology of Ciguatera in Florida.

    Science.gov (United States)

    Radke, Elizabeth G; Reich, Andrew; Morris, John Glenn

    2015-08-01

    Ciguatera is the most commonly reported marine food-borne illness worldwide. Because there is a biological plausibility that ciguatera may be impacted by long-term climate variability and Florida is on the northern border of the geographic distribution of ciguatera, it is important to update our understanding of its epidemiology in Florida. We performed an analysis of 291 reports in Florida from 2000 to 2011 and an e-mail survey of 5,352 recreational fishers to estimate incidence and underreporting and identify high risk demographic groups, fish types, and catch locations. Incidence was 5.6 per 100,000 adjusted for underreporting. Hispanics had the highest incidence rate (relative risk [RR] = 3.4) and were more likely to eat barracuda than non-Hispanics. The most common catch locations for ciguatera-causing fish were the Bahamas and Florida Keys. Cases caused by fish from northern Florida were infrequent. These results indicate that ciguatera incidence is higher than estimated from public health reports alone. There is little evidence that incidence or geographic range has increased because of increased seawater temperatures since earlier studies. © The American Society of Tropical Medicine and Hygiene.

  18. A habitat assessment for Florida panther population expansion into central Florida

    Science.gov (United States)

    Thatcher, C.A.; Van Manen, F.T.; Clark, J.D.

    2009-01-01

    One of the goals of the Florida panther (Puma concolor coryi) recovery plan is to expand panther range north of the Caloosahatchee River in central Florida. Our objective was to evaluate the potential of that region to support panthers. We used a geographic information system and the Mahalanobis distance statistic to develop a habitat model based on landscape characteristics associated with panther home ranges. We used cross-validation and an independent telemetry data set to test the habitat model. We also conducted a least-cost path analysis to identify potential habitat linkages and to provide a relative measure of connectivity among habitat patches. Variables in our model were paved road density, major highways, human population density, percentage of the area permanently or semipermanently flooded, and percentage of the area in natural land cover. Our model clearly identified habitat typical of that found within panther home ranges based on model testing with recent telemetry data. We identified 4 potential translocation sites that may support a total of approximately 36 panthers. Although we identified potential habitat linkages, our least-cost path analyses highlighted the extreme isolation of panther habitat in portions of the study area. Human intervention will likely be required if the goal is to establish female panthers north of the Caloosahatchee in the near term.

  19. Bacterial growth and DOC consumption in a tropical coastal lagoon

    Directory of Open Access Journals (Sweden)

    V. F. Farjalla

    Full Text Available The aims of this research were to determine the main limiting nutrient to bacterial growth in Imboassica lagoon, southeastern Brazil, to estimate the percentage of dissolved organic carbon (DOC available for bacterial growth, and to determine the bacterial growth efficiency (BGE of natural assemblages. Bacterial growth and DOC consumption were determined in batch culture experiments, in which water samples were supplemented with nitrogen and phosphorus together or separately, or incubated without nutrient additions. When added together, N and P stimulated higher bacterial growth rates and production, as well as higher DOC consumption. The BGEs and DOC consumption rates were strongly dependent on the method used to determine bacterial production. The BGE ranged from 11 to 72%. However, only a minor fraction of bulk DOC was consumed by the planktonic bacteria (from 0.7 to 3.4%. The results suggest that low availability of phosphorus and nitrogen coupled with excess organic carbon was the main factor responsible for the relatively low bacterial utilization of DOC in Imboassica lagoon.

  20. Analysis of lagoon sludge characteristics for choice of treatment process

    Energy Technology Data Exchange (ETDEWEB)

    Park, J. H.; Hwang, D. S.; Choi, Y. D.; Lee, K. I.; Hwang, S. T.; Jung, K. J. [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2002-04-01

    The Korea Atomic Energy Research Institute has launched a decommissioning program of uranium conversion plant. One of the important tasks in the decommissioning program is the treatment of the sludge, which was generated during operation and stored in the two ponds of the lagoon. The treatment requires the volume reduction of lagoon sludges for the low cost of the program and the conversion of the chemical forms, including uranium, for the acceptance at the final disposal site. The physical properties, such as densities, were measured and chemical compositions and radiological properties were analyzed. The denitration was a candidate process which would satisfy the requirements for sludge treatment, and the characteristics of thermal decomposition and dissolution with water were analyzed. The main compounds of the sludge were ammonium and sodium nitrate from conversion plant and calcium nitrate, calcium carbonate from Ca precipitation and impurities of the yellow cake. The content of uranium, thorium and Ra-226 was high in pond-1 and low in pond-2 because those were removed during Ca precipitation. On the base of the characteristics of the sludge and available technologies, reviewed in this study and being developed in Korea Atomic Energy Research Institute, two processes were proposed and evaluated in points of the expected technological difficulties. And the cost for treatment of sludges are estimated for both processes. 79 refs., 44 figs., 37 tabs. (Author)

  1. Enteric viruses in a mangrove lagoon, survival and shellfish incidence

    Energy Technology Data Exchange (ETDEWEB)

    Lopez de Cardona, I.; Bermudez, M.; Billmire, E.; Hazen, T.C. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico)

    1988-12-31

    Mangrove oysters (Crassostrea rhizophorae) were screened for enteric viruses. For 18 months oysters were collected from Cano Boqueron, a tropical mangrove lagoon on the southwest coast of Puerto Rico. This popular tourist resort has two primary sewage treatment plants which service 158 single family cabanas. In spite of the heavy seasonal input of sewage to Cano Boqueron and high densities of fecal coliform bacteria, enteric viruses were not detected in shellfish meat. Because no viruses were detected in the oysters, a virus survival study was performed. Poliovirus type 1 was placed in diffusion chambers in situ at two sites in Cano Boqueron. More than 95% of the poliovirus inactivation occurred within 24 h. Virus inactivation was significantly different by site, indicating different inactivation rates within the lagoon. Chamber studies done simultaneously with Escherichia coli did not reveal differences between sites. It is suggested that the sewage effluent had an antiviral effect in the absence of an antibacterial effect. This study demonstrates the importance for establishing microbial contamination standards for shellfish growing waters in the tropics based upon in situ studies with tropical species, e.g. mangrove oyster.

  2. Spatial variability in the icthyoplankton structure of a subtropicalhypersaline lagoon

    Directory of Open Access Journals (Sweden)

    Judson da Cruz Lopes da Rosa

    Full Text Available Abstract The Lagoa de Araruama is a hypersaline ecosystem inhabited by distinct fish species, either permanently or during their reproductive season. Over recent years, some significant environmental changes have been observed in this ecosystem related to the sewage runoff, as salinity decrease (from 64 to 41 psu during the last 40 years and nutrients increase. As both changes are thought to affect the ichthyoplankton assemblage, the present study aimed to evaluate all the potential relationships between salinity disruption and fish larvae distribution. Ichtyoplankton samples were collected monthly from January 2010 to March 2011 at eight sites in Araruama Lagoon by means of a WP2 plankton net equipped with a flowmeter. During this period, low egg densities were coincident with high salinity regions, suggesting that adults are avoiding to release their eggs under less favorable environmental conditions to the larvae. The uneven distribution of eggs and larvae inside the lagoon, as revealed by both spatial and temporal analyses lead us to suggest that changes in salinity have influenced the reproductive rhythms of those fish species that depend upon the Lagoa de Araruama.

  3. Vibrio trends in the ecology of the Venice lagoon.

    Science.gov (United States)

    Rahman, Mohammad Shamsur; Martino, Maria Elena; Cardazzo, Barbara; Facco, Pierantonio; Bordin, Paola; Mioni, Renzo; Novelli, Enrico; Fasolato, Luca

    2014-04-01

    Vibrio is a very diverse genus that is responsible for different human and animal diseases. The accurate identification of Vibrio at the species level is important to assess the risks related to public health and diseases caused by aquatic organisms. The ecology of Vibrio spp., together with their genetic background, represents an important key for species discrimination and evolution. Thus, analyses of population structure and ecology association are necessary for reliable characterization of bacteria and to investigate whether bacterial species are going through adaptation processes. In this study, a population of Vibrionaceae was isolated from shellfish of the Venice lagoon and analyzed in depth to study its structure and distribution in the environment. A multilocus sequence analysis (MLSA) was developed on the basis of four housekeeping genes. Both molecular and biochemical approaches were used for species characterization, and the results were compared to assess the consistency of the two methods. In addition, strain ecology and the association between genetic information and environment were investigated through statistical models. The phylogenetic and population analyses achieved good species clustering, while biochemical identification was demonstrated to be imprecise. In addition, this study provided a fine-scale overview of the distribution of Vibrio spp. in the Venice lagoon, and the results highlighted a preferential association of the species toward specific ecological variables. These findings support the use of MLSA for taxonomic studies and demonstrate the need to consider environmental information to obtain broader and more accurate bacterial characterization.

  4. Spatiotemporal dynamics of submerged macrophytes in a Mediterranean coastal lagoon

    Science.gov (United States)

    Obrador, Biel; Pretus, Joan Lluís

    2010-03-01

    The seasonal and interannual dynamics of the biomass and spatial distribution of a macrophyte meadow were explored in a Mediterranean coastal lagoon (Albufera des Grau, Balearic Islands) from 2002 to 2007. The dynamics in the main physicochemical variables were also analysed to assess the factors involved in the spatiotemporal variability of the submerged macrophytes. The meadows were dominated by Ruppia cirrhosa, which showed a marked seasonal cycle with winter quiescence and complete annual regrowth. The annual production of R. cirrhosa had high interannual variability and was amongst the highest described for this species in the literature, ranging 327-919 gDW m -2. The spatial distribution of macrophytes was determined by light availability and wave exposure, with the highest abundances found in shallow and gently sloped areas sheltered from the strong northerly winds. The interannual variations in macrophyte descriptors (area of occurrence, average depth of the meadows, and maximum biomass) were mainly related to water turbidity and salinity, but the effect of these variables was constrained to the spring and summer months, respectively. A significant negative correlation between the extent of coverage of R. cirrhosa and the water level at the end of the previous annual cycle was observed, suggesting a positive effect of desiccation on the extent of coverage of the macrophytes. After six years of apparent stability, the macrophytes abruptly disappeared from the lagoon. Although the mechanisms are not clear, this shift was likely attributable to a combination of several factors.

  5. The atypical hydrodynamics of the Mayotte Lagoon (Indian Ocean): Effects on water age and potential impact on plankton productivity

    Science.gov (United States)

    Chevalier, C.; Devenon, J. L.; Pagano, M.; Rougier, G.; Blanchot, J.; Arfi, R.

    2017-09-01

    In mesotidal lagoons of the Indian Ocean, the coral reef barrier may be temporarily submerged at high tide and partially exposed at low tide, and this may cause unusual lagoon dynamics. A field measurement campaign was conducted in the north-east Mayotte Lagoon in order to understand these processes. An experimental approach was used, combining measurements taken by 1) a side-mounted Acoustic Doppler Current Profiler (ADCP) on a moving boat along transects through the reef passages (17 transects) and 2) by more conventional high-resolution moored ADCP measurements. A specific tidal analysis methodology was used to determine the spatial variability of the velocity. The tidal hydrodynamics within the lagoon were determined using a numerical model and then analyzed. The tide acted as a quasi-progressive forced wave in the lagoon: at low tide, water entered through the south passage, over the reef and left the lagoon through the north passage. This flow was reversed at high tide. The tide-driven quasi-progressive wave created a specific lagoon dynamics. Contrary to most other channel lagoons, the flow over the reef was mainly outward. This increases the inflow through the passages, which renews the water in the lagoon as shown by the indicators of age and origin of the water inside the lagoon. This study also showed the importance of these indicators for better understanding the variations and levels of plankton biomass (with chlorophyll concentration as proxy) which is quite high in this lagoon.

  6. Mussel farming as a large-scale bioengineering tool: a numerical modelling case study in Rødsand lagoon, Denmark

    DEFF Research Database (Denmark)

    Forsberg, Pernille Louise; Ernstsen, Verner Brandbyge; Lumborg, Ulrik

    Rødsand lagoon in southeast Denmark is a non-tidal coastal lagoon, which is home to a wide range of marine flora and fauna and is protected under Natura 2000. An increase in turbidity within the lagoon may reduce the ecosystem health due to hindered light penetration. A threat to the lagoonal...... ecosystem is related to future increasing storm intensities (Olesen et al., 2014), which are presumed to increase the suspended sediment concentration (SSC) within the lagoon. Furthermore the planned construction of a tunnel between Germany and Denmark may propose a threat to the lagoon due to a possible...... spill of sediment, which could increase the longshore sediment influx to Rødsand lagoon. Mussels can reduce the SSC in marine environments (Schröder et al., 2014), why the implementation of a mussel farm has been considered as a management option. In the present study we developed a module to include...

  7. Impact of mussel bioengineering on fine-grained sediment dynamics in a coastal lagoon: a numerical modelling investigation

    DEFF Research Database (Denmark)

    Forsberg, Pernille Louise; Lumborg, Ulrik; Bundgaard, Klavs

    2017-01-01

    Rødsand lagoon in southeast Denmark is a non-tidal coastal lagoon. It is home to a wide range of marine flora and fauna and part of the Natura 2000 network. An increase in turbidity through elevated levels of suspended sediment concentration (SSC) within the lagoon may affect the ecosystem health...... due to reduced light penetration. Increasing SSC levels within Rødsand lagoon could be caused by increasing storm intensity or by a sediment spill from dredging activities west of the lagoon in relation to the planned construction of the Fehmarnbelt fixed link between Denmark and Germany. The aim...... of the study was to investigate the impact of a mussel reef on sediment import and SSC in a semi-enclosed lagoon through the development of a bioengineering modelling application that makes it possible to include the filtrating effect of mussels in a numerical model of the lagoonal system. The numerical...

  8. Evaluation of the Trophic Level of Kune and Vain Lagoons in Albania, Using Phytoplankton as a Bioindicator

    Directory of Open Access Journals (Sweden)

    Anni Koci Kallfa

    2014-03-01

    Full Text Available Concentration of chlorophyll is an adequate parameter for assessing the trophic state of lagoon ecosystems. Objectives of this study are: selection of a system of bioindicators to enable a good qualitative evaluation of the trophic state of the lagoons and their dynamics; evaluation of seasonal water quality variability and comparison between lagoons. The trophic state of the lagoons is analysed every month over the year. Water samples are retrieved at four different sites (exact coordinates each month, sites that are representative of different water circulation systems at each lagoon. The trophic level in the respective lagoons is thus assessed through selection of an adequate system of bioindicators, in order to observe the oscillations of the amount of chlorophyll and therefore to determine the level of eutrophication. Based on the above parameters, the comparison of the trophic state in these two lagoons has shown that they have different trophic states.

  9. Are Sea Surface Temperature satellite measurements reliable proxies of lagoon temperature in the South Pacific?

    Science.gov (United States)

    Van Wynsberge, Simon; Menkes, Christophe; Le Gendre, Romain; Passfield, Teuru; Andréfouët, Serge

    2017-12-01

    In remote coral reef environments, lagoon and reef in situ measurements of temperature are scarce. Sea Surface Temperature (SST) measured by satellite has been frequently used as a proxy of the lagoon temperature experienced by coral reef organisms (TL) especially during coral bleaching events. However, the link between SST and TL is poorly characterized. First, we compared the correlation between various SST series and TL from 2012 to 2016 in three atolls and one island in the Central South Pacific Ocean. Simple linear correlation between SST and TL ranged between 0.44 and 0.97 depending on lagoons, localities of sensors, and type of SST data. High-resolution-satellite-measurements of SST inside the lagoons did not outperform oceanic SST series, suggesting that SST products are not adapted for small lagoons. Second, we modelled the difference between oceanic SST and TL as a function of the drivers of lagoon water renewal and mixing, namely waves, tide, wind, and season. The multivariate models reduced significantly the bias between oceanic SST and TL. In atoll lagoons, and probably in other hydrodynamically semi-open systems, a correction taking into account these factors is necessary when SST are used to characterize organisms' thermal stress thresholds.

  10. Construction and operation of a covered lagoon methane recovery system for the Cal Poly Dairy

    International Nuclear Information System (INIS)

    Williams, D.W.; Moser, M.A.; Norris, G.

    1999-01-01

    This paper describes the design, construction and anticipated operation of a lagoon-type methane recovery system for the Cal Poly Dairy. The initial design was based upon the present and anticipated herd size, 300 to 600 cows, heifers and calves. The lagoon design meets USDA-NRCS standards, and accounts for limitations of the site, primarily shallow sandstone bedrock. The new lagoon, which has a liquid volume of 14,000 m 3 , was constructed next to an existing lagoon. The new lagoon was covered with a flexible membrane incorporating buoyant material so that the cover floats on the surface, and a gas collection system. The predicted output of the lagoon for the present population of approximately 350 cows, heifers and calves is estimated to average up to 320 m 3 of biogas per day. The biogas will fuel a micro-turbine electric generator, and produce up to 23 kW in parallel with the utility system. Odor control is the most important non-economic benefit. This project will provide environmental benefits-odor control by capturing the odorous gases that result from dairy manure storage; methane, a significant greenhouse gas is kept out of the atmosphere; and water pollution is reduced through the reduction in organic matter in the lagoon. Economic benefits include electricity and process heat, together worth up to 16,000 US dollars per year. (author)

  11. The role of connectivity and hydrodynamic conditions in the configuration of ichthyoplankton assemblages in coastal lagoons

    Science.gov (United States)

    Pérez-Ruzafa, Angel; Quispe, Jhoni I.; Umgiesser, Georg; Ghezzo, Michol; De Pascalis, Francesca; Marcos, Concepción

    2014-05-01

    Fish assemblages in coastal lagoons are constituted by species with different gilds and life stories including estuarine residents but also a high percentage of marine stragglers and marine migrants. Previous studies showed that different ichthyoplancton assemblages can be identified inside a lagoon, depending on hydrological conditions, but at the same time a high spatial and temporal variability haven observed. The proposed models to explain lagoon assemblages configuration based on probabilities of colonization from the open sea involves an important stochastic component and introduces some randomness that could lead to that high spatial and temporal variability at short and long-term scales. In this work we analyze the relationship between ichthyoplankton assemblages in the Mar Menor lagoon and the adjacent open sea in the framework of the hydrodynamics of the lagoon and connectivity between sampling stations using hydrodynamic models. The results, show a complex interaction between the different factors that lead to a highly variable system with high accumulated richness and diversity of species, and a large proportion of occasional visitors and stragglers suggesting that the mechanisms of competitive lottery can play an important role in the maintenance of communities of coastal lagoons , where environmental variability occurs in a system with strong differences in colonization rates and connectivity, not only with the open sea, but also between locations within the lagoon.

  12. Hydrology of Southeast Florida and Associated Topics.

    Science.gov (United States)

    Monsour, William, Comp.; Moyer, Maureen, Comp.

    This booklet deals with the hydrology of southeastern Florida. It is designed to provide the citizen, teacher, or student with hydrological information, to promote an understanding of water resources, and to initiate conservation practices within Florida communities. The collection of articles within the booklet deal with Florida water resources…

  13. Magnitude and variability of methane production and concentration in tropical coastal lagoons sediments

    Directory of Open Access Journals (Sweden)

    Antonella Petruzzella

    Full Text Available AIM: Coastal wetlands are potential zones for methane (CH4 production. The present study aims to evaluate the spatial variation of CH4 production and concentration in ten tropical coastal lagoons, the influence of aquatic macrophytes on the sediment CH4 concentration and how the magnitude of these potential CH4 production rates compare to those in other ecosystems. METHODS: Sediments were sampled in ten coastal lagoons, with one site in the limnetic region and another site in aquatic macrophyte stands when they were present in the littoral region. We measured the CH4 production as a potential rate, and CH4 concentration was directly measured from sediment samples. RESULTS: The highest potential CH4 production (PMP rates were found in alkaline and hypersaline lagoons. However, Cabiúnas, which is a freshwater lagoon densely colonized by aquatic macrophytes, also exhibited a high PMP rate. We also observed that the sediment CH4 concentration in the littoral region was higher than in the limnetic region in all of the investigated lagoons except Paulista, which presented the opposite pattern. The PMP rates observed in the studied lagoons were low compared to other aquatic ecosystems. CONCLUSION: Our results suggest that the sediments of saline lagoons are important CH4 production sites, and in general, aquatic macrophytes have a positive influence on methanogenesis, which was evident based on the CH4 concentrations present in the sediments of these lagoons. Further studies should focus on the processes underlying the CH4 patterns observed in the tropical coastal lagoons, especially concerning the coupling between CH4 production and concentration.

  14. River engineering

    NARCIS (Netherlands)

    De Vries, M.

    1993-01-01

    One dimension models - basic eauations, analytical models, numberical models. One dimensional models -suspended load, roughness and resistance of river beds. Solving river problems - tools, flood mitigation, bank protection.

  15. Miami, Florida: The Magic City

    Science.gov (United States)

    McIntosh, Phyllis

    2008-01-01

    With its subtropical climate and intimate ties to Latin America, Miami is like no other city in the United States. More than 65 percent of its population is Hispanic, and Spanish is the most commonly heard language. Situated at the southern tip of the 500-mile-long Florida peninsula, Miami is the largest urban area in the southeastern United…

  16. Residential Energy Efficiency Potential: Florida

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-16

    Energy used by Florida single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  17. REVIEW: Citanduy river diversion, advantages and disadvantages plan to conserve mangrove ecosystem in Segara Anakan

    Directory of Open Access Journals (Sweden)

    AHMAD DWI SETYAWAN

    2003-01-01

    Full Text Available Mangrove ecosystem at Segara Anakan lagoon, Cilacap having specific characteristics so that in developing this area should consider the conservation aspect. This area is the widest conserved-mangrove ecosystem at Java, and the place for breeding of many species of fish, crustacean and others. Thousand families of fisheries were supported both direct and indirectly from this ecosystem. However, along with the development activities in the watershed of Citanduy, Cimeneng/Cikonde and other rivers connected to the area has brought about the increase of sediment, and threaten the existence of the lagoon and surrounding mangrove ecosystem. Diversion of Citanduy river, dredging sediment, and reboisation of the watershed river was a preference of conserving the ecosystem, however, the diversion could be forming a new ecosystem, that actually threat the fisheries and tourism activities at Pangandaran, Ciamis.

  18. Fauna of gastropod molluscs in the Curonian Lagoon littoral biotopes (Baltic Sea, Kaliningrad region, Russia

    Directory of Open Access Journals (Sweden)

    Dmitry Filippenko

    2011-12-01

    Full Text Available A survey of the gastropod mollusc fauna in the coastal waters of the southern part of the Curonian Lagoon (Kaliningrad region, Russia were carried out. Study revealed 34 aquatic gastropods representing 30% of Prosobranchia and 70% of Pulmonata. Obtained data showed higher mollusc diversity in the littoral biotopes in comparison with open areas of the Lagoon. The fauna is represented by a typical Central European species complex of freshwater gastropods. The reed zone along the coastline in the Lagoon functions as a barrier and provides shallow water habitats with slow moving and warmer water, where maximum gastropod species concentrate.

  19. Lagoon microbialites on Isla Angel de la Guarda and associated peninsular shores, Gulf of California (Mexico)

    Science.gov (United States)

    Johnson, Markes E.; Ledesma-Vázquez, Jorge; Backus, David H.; González, Maria R.

    2012-07-01

    Examples of two closed lagoons with extensive growth of Recent microbialites showing variable surface morphology and internal structure are found on Isla Angel de la Guarda in the Gulf of California. Comparable lagoonal microbialites also occur ashore from Ensenada El Quemado on the adjacent peninsular mainland of Baja California. The perimeters of all three lagoons feature crusted structures indicative of thrombolites with a knobby surface morphology 2 cm to 3 cm in relief and internal clotting without any sign of laminations. Outward from this zone, thrombolitic construction thins to merge with a white calcified crust below which a soft substratum of dark organic material 4 cm to 6 cm in thickness is concealed. The substratum is laminated and heavily mucilaginous, as observed along the edges of extensive shrinkage cracks in the overlying crust. The thrombolitic crust is anchored to the shore, while the thinner crust and associated stromatolitic mats float on the surface of the lagoons. Laboratory cultures of the dark organic material yielded the solitary cyanobacterium Chroococcidiopsis as the predominant taxon interspersed with filamentous forms. In decreasing order of abundance, other morphotypes present include Phormidium, Oscillatoria, Geitlerinema, Chroococus, and probably Spirulina. The larger of the two island lagoons follows an east-west azimuth and covers 0.225 km2, while the smaller lagoon has a roughly north-south axis and covers only 0.023 km2. The salinity of water in the smaller lagoon was measured as148 ppt. Pliocene strata along the edge of the smaller modern lagoon include siltstone bearing calcified platelets suggestive of a microbial origin. Dry lagoons abandoned during the later Quaternary occur inland at higher elevations on the island, but retain no fossils except for sporadic white crusts cemented on cobbles around distinct margins. Raised Quaternary lagoons parallel to the big lagoon on Isla Angel de la Guarda are partly obscured by flood

  20. Toxicological biomarkers in the analysis of Orbetello lagoon (Italy); Biomarkers nella valutazione della qualita' di un sistema lagunare

    Energy Technology Data Exchange (ETDEWEB)

    Fossi, M. C.; Mori, G.; Baroni, D.; Bianchi, N. [Siena Univ., Siena (Italy). Dipt. di Scienze Ambientali

    2001-08-01

    Toxicological risk assessment in the Orbetello lagoon (Grosseto, Italy) was carried by two approaches: biomonitoring based on estimates of residue levels in indicator species and biomarkers studies by which their responses to chemical and environmental stress were evaluated. In specimens of Carcinus aestuarii sampled in three differently impacted areas of the lagoon, levels of chlorinated hydrocarbons (DDTs, PCBs and HCBs), heavy metals (Pb, Cd and Hg) and 3 specific biomarkers (mixed function oxidase (MFO) induction, butyrylcholinesterase (BChE) inhibition and porphyrin accumulation) were measured. Overall results indicate that the lagoon is highly polluted. Of the three study sites, the highest concentrations of HCBs, DDTs and PCBs were observed in specimens from the mouth of the river Albegna, in which butyrylcholinesterase induction usually attributed to organophosphates (OPs) and carbamates (CBs), was considerable, as well. Specimens from S. Liberata, once known to be the most pristine site, showed clear signs of environmental degradation with high levels of Pb, Cd and organochlorine compounds, including PCBs. Benzopyrene monooxygenase (BPMO) values also seem to confirm such chemical stress. High levels of Hg and largely accumulated protoporphyrins and total porphyrins in C. aestuarii of the Sitoco site are only partially ascribed to the occurrence of Hg, as the presence of some unknown xenobiotics is likely. [Italian] In questo studio e' stato valutato il potenziale pericolo di composti inquinanti su una comunita' naturale della Laguna di Orbetello (Grosseto) utilizzando sia indagini di biomonitoraggio basate sulla stima dei livelli di residui in organismi bioindicatori, si una metodologia innovativa come lo studio di biomarkers (intendendo con cio' la valutazione delle risposte che un organismo genera nei confronti di uno strss chimico-ambientale). Su esemplari di Carcinus aestuarii, scelti come organismi bioindicatori e campionati in tre aree

  1. Temporal shifts in reef lagoon sediment composition, Discovery Bay, Jamaica

    Science.gov (United States)

    Perry, Christopher T.; Taylor, Kevin G.; Machent, Philip G.

    2006-03-01

    Discovery Bay, north Jamaica, forms a large (1.5 km wide), deep (up to 56 m) embayment that acts as a sink for reef-derived and lagoonal carbonate sediments. Since the mid-1960s, the bay has also provided a sink for inputs of bauxite sediment that are spilled during loading at a boat terminal constructed within Discovery Bay. Bauxite has accumulated across much of the southern section of the bay with surficial sediments presently composed of up to 35 weight% non-carbonate. Cores recovered from sites on the western side of the bay provide a stratigraphic record of this history of bauxite contamination across water depths from 5 to 25 m. The bauxite-influenced upper sediment horizons are clearly visible in each core from the distinctive red-brown colouration of the sediment. These sediments are composed of approximately 10% non-carbonate (bauxite) and have Fe contents of around 2-3000 μg/g (up to 7000 μg/g). The thickness of this upper bauxite-contaminated sequence increases down transect (approximately 18 cm in the shallowest core, to around 47 cm in the deepest core), and in each core overlies a sequence of 'clean' lagoon carbonates. These typically are poorly sorted carbonate sands with variable amounts of coral rubble. Down-core data on CaCO 3 and Fe content provide a chemical record of decreasing sediment contamination with depth, with the lower 'clean' carbonates composed of only around 2% non-carbonate and coral, mollusc, Amphiroa and Halimeda in the clean lagoon sands, to assemblages dominated by Halimeda and Amphiroa within the surficial sediments. At the deeper sites, no major down-core shifts in sediment constituents occur. These sites thus record a rather complex history of changes in sediment composition and chemistry. Clear shifts in chemistry and stratigraphy occur in all the cores and reflect progressive bauxite contamination in the near-surface horizons. These inputs, however, do not appear to have directly affected carbonate production, since the

  2. Influence of CDOM and particle composition on ocean color of the Eastern New Caledonia Lagoon during the CALIOPE cruises

    Science.gov (United States)

    Dupouy, Cécile; Röttgers, Rüdiger; Tedetti, Marc; Martias, Chloe; Murakami, Hiroshi; Doxaran, David; Lantoine, Francois; Rodier, Martine; Favareto, Luciane; Kampel, Milton; Goutx, Madeleine; Frouin, Robert J.

    2014-11-01

    Ocean color of tropical lagoons is dependent on bathymetry and bottom type, as well as input of coastal living and mineral particles and chromophoric dissolved organic matter (CDOM). The New Caledonia lagoon lies in the Southwestern Tropical Pacific around 21° 30'S and 166° 30'E, with a great marine biodiversity in UNESCO Heritage coral reefs, benthic sea grass, and benthic communities. They are largely connected to the open ocean in the southern and eastern parts, but only by narrow passes in the southwest part. The trophic state is linked to spatial variations in flushing times. High run offs due to rain carrying abundant chromophoric dissolved organic matter (CDOM) and particle loads may greatly impact the functioning of ecosystems while rivers and sewage effluents may induce localized impacts. Two oceanographic cruises (CALIOPE 1 in 2011 and CALIOPE 2 in 2014) were carried out off the Eastern Coast of New Caledonia during a calm dry period and during high winds, respectively. Multi- and hyper-spectral marine reflectance was measured with a SIMBADA instrument and a TRIOS radiometer system, together with inherent optical properties (total and CDOM absorption coefficients with a PSICAM, in situ absorption and scattering with an AC9, backscattering with a Hydroscat-6). Fluorescence of CDOM (EEM/PARAFAC) was measured on collected 0.2 μm filtered samples. In 2014, Satlantic and FieldSpec hyper-spectral radiometers were available for in-water profiling of upwelling radiance and downwelling irradiance and above-water reflectance measurements, respectively. Inherent and apparent optical data from the two cruises are compared and used to estimate ocean color algorithms performance and evaluate a Linear Matrix Inversion method, providing tools for remote sensing on this highly under-sampled coastal region of New Caledonia.

  3. Escherichia coli pollution in a Baltic Sea lagoon: a model-based source and spatial risk assessment.

    Science.gov (United States)

    Schippmann, Bianca; Schernewski, Gerald; Gräwe, Ulf

    2013-07-01

    Tourism around the Oder (Szczecin) Lagoon, at the southern Baltic coast, has a long tradition, is an important source of income and shall be further developed. Insufficient bathing water quality and frequent beach closings, especially in the Oder river mouth, hamper tourism development. Monitoring data gives only an incomplete picture of Escherichia coli (E. coli) bacteria sources, spatial transport patterns, risks and does neither support an efficient bathing water quality management nor decision making. We apply a 3D ocean model and a Lagrangian particle tracking model to analyse pollution events and to obtain spatial E. coli pollution maps based on scenario simulations. Model results suggests that insufficient sewage treatment in the city of Szczecin is the major source of faecal pollution, even for beaches 20km downstream. E. coli mortality rate and emission intensity are key parameters for concentration levels downstream. Wind and river discharge play a modifying role. Prevailing southwestern wind conditions cause E. coli transport along the eastern coast and favour high concentration levels at the beaches. Our simulations indicate that beach closings in 2006 would not have been necessary according to the new EU-Bathing Water Quality Directive (2006/7/EC). The implementation of the new directive will, very likely, reduce the number of beach closings, but not the risk for summer tourists. Model results suggest, that a full sewage treatment in Szczecin would allow the establishment of new beaches closer to the city (north of Dabie lake). Copyright © 2013 Elsevier GmbH. All rights reserved.

  4. The zoobenthic community of the Orbetello Lagoon (Central Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Morgana, J G; Naviglio, L [ENEA Casaccia, S. Maria di Galeria, Rome (Italy). Dipt. Ambiente. AMB - PRO - ECO

    1996-12-31

    In this paper an analysis of the macrozoobenthic community structure of the Orbetello Lagoon is shown. During the study period taxa number, density, indices of diversity (Shannon), evenness (Pielou), richness (Margalef) and dominance (Simpson) were calculated for each sampling site. The similarity in species composition among was evaluated by community coefficients: a cluster analysis (UPGMA method) shows that the station 8 (near Ansedonia channel) and the station 4 ( in front of Patanella, near Fibbia channel) are very much alike (community coefficient = 82.86), whilst the station 1 (near Nassa channel) and the station 9 (near the domestic sewage of Orbetello Town) differ markedly from the other stations. The animal biomass (ash free dry weight) and the frequencies of trophic groups of each sampling site were estimated; the authors have found higher proportions of deposit feeders than suspension feeders in all the sampling sites.

  5. The zoobenthic community of the Orbetello Lagoon (Central Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Morgana, J.G.; Naviglio, L. [ENEA Casaccia, S. Maria di Galeria, Rome (Italy). Dipt. Ambiente. AMB - PRO - ECO

    1995-12-31

    In this paper an analysis of the macrozoobenthic community structure of the Orbetello Lagoon is shown. During the study period taxa number, density, indices of diversity (Shannon), evenness (Pielou), richness (Margalef) and dominance (Simpson) were calculated for each sampling site. The similarity in species composition among was evaluated by community coefficients: a cluster analysis (UPGMA method) shows that the station 8 (near Ansedonia channel) and the station 4 ( in front of Patanella, near Fibbia channel) are very much alike (community coefficient = 82.86), whilst the station 1 (near Nassa channel) and the station 9 (near the domestic sewage of Orbetello Town) differ markedly from the other stations. The animal biomass (ash free dry weight) and the frequencies of trophic groups of each sampling site were estimated; the authors have found higher proportions of deposit feeders than suspension feeders in all the sampling sites.

  6. Biogeochemical Impact of Hurricane Harvey on Texas Coastal Lagoons

    Science.gov (United States)

    Montagna, P.; Hu, X.; Walker, L.; Wetz, M.

    2017-12-01

    Hurricane Harvey made landfall Friday 25 August 2017 as a Category 4 hurricane, which is the strongest hurricane to hit the middle Texas coast since Carla in 1961. After the wind storm and storm surge, coastal flooding occurred due to the storm lingering over Texas for four more days, dumping as much as 50" of rain near Houston, producing 1:1000 year flood event. The Texas coast is characterized by lagoons behind barrier islands, and their ecology and biogeochemistry are strongly influenced by coastal hydrology. The ensuing inflow event replaced brackish water with fresh water that was high in inorganic an organic matter, significantly enhancing respiration of coastal blue carbon, and dissolved oxygen went to zero for a long period of time. Recovery will likely take months or nearly one year.

  7. Satellite-Observed Black Water Events off Southwest Florida: Implications for Coral Reef Health in the Florida Keys National Marine Sanctuary

    Directory of Open Access Journals (Sweden)

    Brian Lapointe

    2013-01-01

    Full Text Available A “black water” event, as observed from satellites, occurred off southwest Florida in 2012. Satellite observations suggested that the event started in early January and ended in mid-April 2012. The black water patch formed off central west Florida and advected southward towards Florida Bay and the Florida Keys with the shelf circulation, which was confirmed by satellite-tracked surface drifter trajectories. Compared with a previous black water event in 2002, the 2012 event was weaker in terms of spatial and temporal coverage. An in situ survey indicated that the 2012 black water patch contained toxic K. brevis and had relatively low CDOM (colored dissolved organic matter and turbidity but high chlorophyll-a concentrations, while salinity was somewhat high compared with historical values. Further analysis revealed that the 2012 black water was formed by the K. brevis bloom initiated off central west Florida in late September 2011, while river runoff, Trichodesmium and possibly submarine groundwater discharge also played important roles in its formation. Black water patches can affect benthic coral reef communities by decreasing light availability at the bottom, and enhanced nutrient concentrations from black water patches support massive macroalgae growth that can overgrow coral reefs. It is thus important to continue the integrated observations where satellites provide synoptic and repeated observations of such adverse water quality events.

  8. Threatened and Endangered Species Survey for Patrick Air Force Base, Florida

    Science.gov (United States)

    Oddy, Donna M.; Stolen, Eric D.; Schmalzer, Paul A.; Larson, Vickie L.; Hall, Patrice; Hensley, Melissa A.

    1997-01-01

    characteristic of species that occur in the Indian River Lagoon system. Twenty-five species of waterbirds were observed during quarterly surveys on PAFB, including five species listed as species of special concern by the state of Florida: Snowy Egret (Egretta thula), Little Blue Heron (Egretta caerulea), Tricolored Heron (Egretta tricolo4, White Ibis (Eudocimus albus), and Brown Pelican (Pelecanus occidentalis). The Golf Course was used extensively by almost all species of waterbirds on PAFB. Twenty-two species of shorebirds were observed on PAFB. Although no listed species were observed, the potential exists for several protected species of shorebirds to use the beach at PAFB during some parts of the year. The Airfield runways and associated grass areas were important sites at PAFB for loafing and feeding for some shorebirds. Surveys of rooftop nesting by Least Terns (Stema antillarum) on PAFB found a large colony on a rooftop in the PAFB Industrial Area. This colony produced some independent young. Two rooftop Least Tern colonies reported from previous years were inactive during 1996. A small number of Black Skimmers (Rhynchops nigee attempted to nest at the Least Ten colony but were unsuccessful. Surveys for the gopher tortoise (Gopherus polyphemus) revealed burrows and tortoises only at the Waste Study Site; five burrows and three tortoises were observed. No Florida scrub lizards (Sceloporus woodi), eastern indigo snakes (Drymarchon corais couperl), or diamondback terrapins (Malademys terrapin terrapin) were observed. American alligators (Alligator mississippiensis) were observed on the Golf Course and using ditches, ponds, and areas along the Banana River. The amount of dune habitat could be expanded by not mowing areas adjacent to the dunes to allow dune species to colonize and expand. Planting dune species as part of the beach renourishment project will also increase this habitat. Exotic plants dominate several areas on the base and are used by threatened, endangered, and

  9. Biological control of trace metal and organometal benthic fluxes in a eutrophic lagoon (Thau Lagoon, Mediterranean Sea, France)

    Science.gov (United States)

    Point, D.; Monperrus, M.; Tessier, E.; Amouroux, D.; Chauvaud, L.; Thouzeau, G.; Jean, F.; Amice, E.; Grall, J.; Leynaert, A.; Clavier, J.; Donard, O. F. X.

    2007-04-01

    In situ benthic chamber experiments were conducted in the Thau Lagoon that allowed the simultaneous determination of the benthic exchanges of trace metals (Cd, Co, Cu, Mn, Pb and U) and mercury species (iHg and MMHg). Fluxes of organotin compounds (MBT, DBT and TBT) were also investigated for the first time. The benthic incubations were performed during two campaigns at four stations that presented different macrobenthic and macrophytic species distribution and abundance (see [Thouzeau, G., Grall, J., Clavier, J., Chauvaud, L., Jean, F., Leynaert, A., Longpuirt, S., Amice, E., Amouroux, D., 2007. Spatial and temporal variability of benthic biogeochemical fluxes associated with macrophytic and macrofaunal distributions in the Thau lagoon (France). Estuarine, Coastal and Shelf Science 72 (3), 432 446.]). The results indicate that most of the flux intensity as well as the temporal and spatial variability can be explained by the combined influence of microscale and macroscale processes. Microscale changes were identified using Mn flux as a good indicator of the redox conditions at the sediment water interface, and by extension, as an accurate proxy of benthic fluxes for most trace metals and mercury species. We also observed that the redox gradient at the interface is promoted by both microbial and macrobenthic species activity that governs O2 budgets. Macroscale processes have been investigated considering macrobenthic organisms activity (macrofauna and macroalgal cover). The density of such macroorganisms is able to explain most of the spatial and temporal variability of the benthic metal fluxes within a specific site. A tentative estimation of the flux of metals and organometals associated with deposit feeder and suspension feeder activity was found to be in the range of the flux determined within the chambers for most considered elements. Furthermore, a light/dark incubation investigating a dense macroalgal cover present at the sediment surface illustrates the role

  10. Molecular Characterization of Swine Manure Lagoon Microbial and Antibiotic Resistant Populations

    Science.gov (United States)

    Background: The differences in swine manure lagoon effluent based on differing management styles or approaches such as different stages of swine rearing determines the presence of variable antibiotic resistance determinants and functional microbial populations. These concerns determine the suitabil...

  11. Mysidacea (Crustacea) from the Minicoy lagoon (Lakshadweep, India) with description of a new species of Anisomysis

    Digital Repository Service at National Institute of Oceanography (India)

    Biju, A.; Panampunnayil, S.U.; Prabhakaran, M.P.

    Four species of mysids collected from the Minicoy lagoon are reported. Anisomysis minicoyensis sp. nov. is distinguished from the related species by the shape of the rostrum, the relative length of the antennal scale and the short protuberances...

  12. Precise determination of the concentration of radiocesium in the water of Mururoa lagoon

    International Nuclear Information System (INIS)

    Bourlat, Y.; Martin, G.

    1992-01-01

    The aim of this study was to determine with maximal precision the concentration of 137 Cs in the water of Mururoa lagoon and to verify if traces of 134 Cs as reported by the Fondation Cousteau in June 1987, were present in the lagoon. Eighteen 1000-litre samples of water were collected from stations within the lagoon during June and July of 1990. Low-level gamma-ray spectrometry was used to determine cesium radionuclides. The concentration of 137 Cs ranged between 2.6 and 3.0 Bq/m 3 (mean 2.79 Bq/m 3 ), which is in good agreement with the annual measurements made by the Service Mixte de Securite Radiologique (SMSR) during systematic monitoring of the lagoon water. No trace of 134 Cs was detected. (author)

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

    International Nuclear Information System (INIS)

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

    1980-01-01

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

  14. Primary productivity of marine macrophytes in the coral reef lagoon of the Kadmat Island, Lakshadweep

    Digital Repository Service at National Institute of Oceanography (India)

    Dhargalkar, V.K.; Shaikh, N.

    n situ primary productivity measurements were carried out with different macrophyte species (belonging to four groups) dominating the benthic communities in the coral reef lagoon of the Kadmat Island of the Lakshadweep Archipelago...

  15. The tidal hydrodynamics modeling of the Topolobampo coastal lagoon system and the implications for pollutant dispersion

    International Nuclear Information System (INIS)

    Montano-Ley, Y.; Peraza-Vizcarra, R.; Paez-Osuna, F.

    2007-01-01

    The tidal hydrodynamics of the Topolobampo coastal lagoon system (Mexico) has been investigated through a modified two dimensional non-linear hydrodynamic finite difference model. The advective and diffusive process acting over a hypothetical pollutant released into the coastal lagoon have also been simulated. Maxima tidal currents (0.85 m/s) were predicted within the main channel, in agree with direct measurements. The direction of the observed fastest currents (SW), also agree quite well with the direction of the strongest tidal current predicted in this investigation, which occur during the ebb when the water of the coastal lagoon is discharged into the Gulf of California. Residual currents (0.01-0.05 m/s) were also predicted. The hypothetical pollutant released within the Topolobampo Harbor would spread to both Ohuira and Topolobampo sections, reaching the inlet after approximately 12 days. - A model has been developed to simulate the tidal hydrodynamics and the behavior of a pollutant in the Topolobampo lagoon

  16. Grain size analysis of beach sediment along the barrier bar lagoon ...

    African Journals Online (AJOL)

    Grain size analysis of beach sediment along the barrier bar lagoon coastal system, Lagos, Nigeria; its implication on coastal erosion. R Abdulkarim, EA Akinnigbagbe, DO Imo, MT Imhansoloeva, VO Aniebone, MP Ibitola, BR Faleye, O Shonde, YJ Appia ...

  17. Problems and Alternatives of Settlement Lagoons for Mine Water Treatment System

    Science.gov (United States)

    Lee, Dong-Kil

    2015-04-01

    A field test and computational flow analysis were conducted to identify the structural problems with existing settlement lagoons and to propose effective alternatives. When it comes to existing settlement lagoons without any specifically designed internal structure, mine water flows along a specific route while other regions remained stagnant. Such a flow pattern along a specific region causes a significant reduction in retention time as well as the ineffective use of the space in a settlement lagoon. When applying the modified settlement lagoon design proposed in this study, the flow distribution of mine drainage became uniform and the time taken for mine drainage to reach the outlet was improved by as much as 360 times and the exchange efficiency was significantly enhanced from 14.5% to 82.7%.

  18. Characterization Of Dissolved Organic Mattter In The Florida Keys Ecosystem

    Science.gov (United States)

    Adams, D. G.; Shank, G. C.

    2009-12-01

    Over the past few decades, Scleractinian coral populations in the Florida Keys have increasingly experienced mortality due to bleaching events as well as microbial mediated illnesses such as black band and white band disease. Such pathologies seem to be most correlated with elevated sea surface temperatures, increased UV exposures, and shifts in the microbial community living on the coral itself. Recent studies indicate that corals’ exposure to UV in the Florida Keys is primarily controlled by the concentration of CDOM (Chromophoric Dissolved Organic Matter) in the water column. Further, microbial community alterations may be linked to changes in concentration and chemical composition of the larger DOM (Dissolved Organic Matter) pool. Our research characterized the spatial and temporal properties of DOM in Florida Bay and along the Keys ecosystems using DOC analyses, in-situ water column optical measurements, and spectral analyses including absorbance and fluorescence measurements. We analyzed DOM characteristics along transects running from the mouth of the Shark River at the southwest base of the Everglades, through Florida Bay, and along near-shore Keys coastal waters. Two 12 hour time-series samplings were also performed at the Seven-Mile Bridge, the primary Florida Bay discharge channel to the lower Keys region. Photo-bleaching experiments showed that the chemical characteristics of the DOM pool are altered by exposure to solar radiation. Results also show that DOC (~0.8-5.8 mg C/L) and CDOM (~0.5-16.5 absorbance coefficient at 305nm) concentrations exhibit seasonal fluctuations in our study region. EEM analyses suggest seasonal transitions between primarily marine (summer) and terrestrial (winter) sources along the Keys. We are currently combining EEM-PARAFAC analysis with in-situ optical measurements to model changes in the spectral properties of DOM in the water column. Additionally, we are using stable δ13C isotopic analysis to further characterize DOM

  19. 33 CFR 334.500 - St. Johns River, Atlantic Ocean, Sherman Creek; restricted areas and danger zone, Naval Station...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false St. Johns River, Atlantic Ocean... AND RESTRICTED AREA REGULATIONS § 334.500 St. Johns River, Atlantic Ocean, Sherman Creek; restricted areas and danger zone, Naval Station Mayport, Florida. (a) The areas. (1) The St. Johns River restricted...

  20. Dynamics of pollution-indicator and heterotrophic bacteria in sewage treatment lagoons.

    OpenAIRE

    Legendre, P; Baleux, B; Troussellier, M

    1984-01-01

    The spatio-temporal dynamics of pollution-indicator bacteria and aerobic heterotrophic bacteria were studied in the sewage treatment lagoons of an urban wastewater center after 26 months of biweekly sampling at eight stations in these lagoons. Robust statistical methods of time-series analysis were used to study successional steps (through chronological clustering) and rhythmic behavior through time (through contingency periodogram). The aerobic heterotrophic bacterial community showed two ty...

  1. Bank filtration drinking water treatment in a costal lagoon in south Brazil

    OpenAIRE

    Romero-Esquivel, Luis Guillermo; Segalla-Pizzolatti, Bruno; Luiz-Sens, Mauricio

    2012-01-01

    Bank filtration (BF) consists in obtaining drinking water from wells in alluvial aquifers or other unconsolidated deposits hydraulically connected with a surface water source. The possibility of applying this technique was evaluated in a pilot scale on the banks of the Lagoa do Peri lagoon, Brazil. Observation and grain size analysis showed that the bottom of the lagoon and the adjacent aquifer have sandy texture. In addition, tests of constant head permeameter, standpipe falling head and a p...

  2. Environmental conditions and biotic communities in Foz de Almargem and Salgados coastal lagoons, Algarve (South Portugal)

    OpenAIRE

    Coelho, Susana Isabel Eusébio

    2013-01-01

    The present study intended to compare environmental conditions and biotic communities of two choked coastal lagoons located in the Algarve region, Foz de Almargem and Salgados, with the purpose of evaluating the effects of organic pollution from wastewater discharges in water quality and biotic communities from different levels of the food chain, namely phytoplankton and benthic macroinvertebrates. Both lagoons were seasonally connected to the sea, but most of the year they were isolated r...

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

    OpenAIRE

    Daniel Arceo-Carranza; Xavier Chiappa-Carrara

    2015-01-01

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

  4. Methanogenesis in an impacted and two dystrophic coastal lagoons (Macaé, Brazil)

    OpenAIRE

    Furtado, André Luiz dos Santos; Casper, Peter; Esteves, Francisco de Assis

    2002-01-01

    This study investigated the methanogenic activity in sediment of the Imboacica (human impacted), Cabiúnas and Comprida coastal lagoons in Rio de Janeiro State (Brazil). Methane was not detected in water and sediment samples from the three lagoons. The measured nutrient concentrations in the pore-water indicated that methanogens activity was not limited by nutrients. Methanogenic activity was not detected under in vitro conditions, indicating that terminal organic carbon mineralisation via met...

  5. Natural revegetation of coal fly ash in a highly saline disposal lagoon in Hong Kong

    Energy Technology Data Exchange (ETDEWEB)

    Chu, L.M. [Chinese University of Hong Kong, Hong Kong (China). Dept. of Biology

    2008-08-15

    Question: What is the relationship of the naturally colonizing vegetation and substrate characteristics in fly ash lagoons? Location: West lagoon, Deep Bay, a 13-ha coastal lagoon in Hong Kong in subtropical Southeast Asia. Methods: Vegetation establishment was examined in a coal fly ash lagoon two years after its abandonment to investigate the distribution of vegetation in relationship to the chemical properties of the fly ash in the lagoon. A greenhouse experiment assessed the limits imposed on plant growth in fly ash. Results: The fly ash was saline, slightly alkaline and very poor in organic matter and nitrogen. Ash from bare and vegetated areas differed significantly in their salinity and extractable concentrations of inorganic nitrogen and various metals. Bare ash had a significantly higher conductivity and extractable sodium, aluminum, manganese, potassium. and lead. In total 11 plant species that belonged to seven families were found growing on the fly ash: all species except the shrub Tamarix chinensis were herbaceous. Using discriminant analysis, the most important factors in distinguishing bare and vegetated ashes were conductivity and sodium. Cluster analysis of bare samples gave two distinct groups, one from the periphery of the lagoon, which had lower sodium, conductivity, organic carbon, potassium and copper, and the other from a second group that contained ashes from the central region of the lagoon. Results of the greenhouse experiment showed that the inhibition of plant growth was significantly correlated with the presence of soluble toxic elements in ash. Conclusion: Toxicity and salinity seem to be the major limiting factors to plant establishment in fly ash, and these factors must be ameliorated for the successful reclamation of these fly ash lagoons.

  6. The Dynamics of Mercury Speciation and Transport at a Central California Coastal Lagoon

    Science.gov (United States)

    Ganguli, P. M.; Swarzenski, P. W.; Dimova, N. T.; Merckling, J.; Kehrlein, N. C.; Hohn, R. A.; Richardson, C. M.; Johnson, C. D.; Fisher, A. T.; Lamborg, C. H.; Flegal, A. R., Jr.

    2014-12-01

    We evaluated spatial and temporal trends in total mercury and monomethylmercury (MMHg) in groundwater, lagoon water, and nearshore seawater to assess the drivers of MMHg production in a coastal lagoon system. Many West Coast streams transition from estuarine to lagoon conditions in the dry season when a sand berm develops at the stream mouth, restricting surface water exchange with the ocean. Because lagoons accumulate nutrients from their upstream watershed they are susceptible to eutrophication, which can promote the growth of anaerobic bacteria. In nearshore settings, these bacteria are primarily responsible for producing MMHg, a bioaccumulative neurotoxin. We found that MMHg concentrations in lagoon water (1 - 5 pM) were higher than in groundwater (0.2 - 1 pM) and coastal seawater (0.1 - 0.6 pM). Groundwater depth profiles combined with subsurface resistivity images suggest MMHg in lagoon water was transported through the sand berm to adjacent seawater. MMHg in seawater and groundwater followed similar trends, providing additional evidence of groundwater-surface water interaction. MMHg in groundwater directly below the lagoon was consistently higher where dissolved oxygen and NO3- decreased, implying MMHg production by anaerobic bacteria. Over a ~7-hour period we observed a 0.6 pM decrease in groundwater MMHg (1 to 0.4 pM) that coincided with a decrease in water temperature (16.5 to 13 °C). We hypothesize that microbial activity, and consequently MMHg production, were enhanced in warmer water. Because coastal lagoons support intricate food webs and serve as nurseries for a variety of organisms, processes that influence mercury speciation and transport in these ecosystems may have a disproportionate impact on nearshore mercury biogeochemical cycling.

  7. Assessment of the trophic state of a hypersaline-carbonatic environment: Vermelha Lagoon (Brazil.

    Directory of Open Access Journals (Sweden)

    Lazaro Laut

    Full Text Available Vermelha Lagoon is a hypersaline shallow transitional ecosystem in the state of Rio de Janeiro (Brazil. This lagoon is located in the protected area of Massambaba, between the cities of Araruama and Saquarema (Brazil, and displays two quite uncommon particularities: it exhibits carbonate sedimentation and displays the development of Holocene stromatolites. Due to both particularities, the salt industry and property speculation have been, increasingly, generating anthropic pressures on this ecosystem. This study aims to apply a multiproxy approach to evaluate the trophic state of Vermelha Lagoon based on physicochemical parameters and geochemical data for the quantification and qualification of organic matter (OM, namely total organic carbon (TOC, total sulfur (TS, total phosphorus (TP and biopolymeric carbon (BPC, including carbohydrates (CHO, lipids (LIP and proteins (PTN. The CHO/TOC ratio values suggest that OM supplied to the sediment is of autochthonous origin and results, essentially, from microbial activity. The cluster analyses allowed the identification of four regions in Vermelha Lagoon. The Region I included stations located in shallow areas of the eastern sector of Vermelha lagoon affected by the impact of the artificial channel of connection with Araruama Lagoon. The Region II, under the influence of salt pans, is characterized by the highest values of BPC, namely CHO promoted by microbiological activity. The Region III include stations spread through the lagoon with high values of dissolved oxygen and lower values of TP. Stromatolites and microbial mattes growth was observed in some stations of this sector. Region IV, where the highest values of TOC and TS were found, represents depocenters of organic matter, located in general in depressed areas. Results of this work evidences that the Vermelha Lagoon is an eutrophic but alkaline and well oxygenated environment (at both water column and surface sediment where the autotrophic

  8. Calibration of Linked Hydrodynamic and Water Quality Model for Santa Margarita Lagoon

    Science.gov (United States)

    2016-07-01

    was used to drive the transport and water quality kinetics for the simulation of 2007–2009. The sand berm, which controlled the opening/closure of...TECHNICAL REPORT 3015 July 2016 Calibration of Linked Hydrodynamic and Water Quality Model for Santa Margarita Lagoon Final Report Pei...Linked Hydrodynamic and Water Quality Model for Santa Margarita Lagoon Final Report Pei-Fang Wang Chuck Katz Ripan Barua SSC Pacific James

  9. The environmental impacts of land transformation in the coastal perimeter of the Mar Menor lagoon (Spain)

    OpenAIRE

    GARCÍA-AYLLON VEINTIMILLA, SALVADOR; Miralles García, José Luis

    2014-01-01

    Assigned to WIT Press all rights under copyright that may exist in and to the Work and any associated written or multimedia components or other enhancements accompanying the Work. The distinctive environment of the lagoon has long been attractive for visitors. A surge in touristic activities has taken place in the area since the early 1960s, characterised by intense urban development along the lagoon s perimeter to accommodate the growing seasonal population. This phenomenon has particular...

  10. Lagoon-sea exchanges, nutrient dynamics and water quality management of the Ria Formosa (Portugal)

    Science.gov (United States)

    Newton, Alice; Mudge, Stephen M.

    2005-02-01

    Historical data from the Ria Formosa lagoon are classified according to the EEA 2001 guidelines to provide a frame of reference to evaluate the effect of management during the implementation of the environmental legislative Directives. Water samples from the Ria Formosa lagoon were significantly enriched in nitrogen (NH 4+ NO 2- and NO 3-) with respect to the adjacent coastal waters indicating that inputs from sewage, agricultural runoff and benthic fluxes were not fully assimilated within the lagoon. Tidal flushing was insufficient in the inner areas of the lagoon to remove or effectively dilute these inputs. Enrichment was most severe close to the urban centres of Faro and Olhão, as well as in the Gilão Estuary and the shallow extremities. Dissolved oxygen undersaturation (mean 75% during daylight hours) was associated with the area close to the sewage outlets of Faro. In the shallow west end of the lagoon during summer, dissolved oxygen supersaturation reached 140% during the day but fell to 50% at night. Classification using the EEA (2001) guidelines suggests the system is "poor" or "bad" with respect to phosphate concentrations for the majority of the year and "poor" in nitrogen contamination during the autumn rainy period. Due to the high overall nitrogen load in the lagoon, there is a net export to the coastal waters, especially during November and December, and phosphate only becomes limiting briefly during the spring bloom (April). Therefore, substantial phytoplankton populations may be supported year-round in the lagoon. The consequences of water quality deterioration in the Ria Formosa would negatively affect the lagoon as a regional resource, important for its ecological, economic and recreational value. The industries most affected would be tourism, fisheries and aquaculture. Management options include Urban Waste Water Treatment, dredging, artificial inlets, limits on urban development and changes in agricultural practices.

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

    Directory of Open Access Journals (Sweden)

    Rayanne Barros Setubal

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

  12. Nutrient budgets and trophic state in a hypersaline coastal lagoon: Lagoa de Araruama, Brazil

    Science.gov (United States)

    Souza, Marcelo F. L.; Kjerfve, Björn; Knoppers, Bastiaan; Landim de Souza, Weber F.; Damasceno, Raimundo N.

    2003-08-01

    Lagoa de Araruama in the state of Rio de Janeiro, Brazil, is a hypersaline lagoon with salinity varying spatially from 45 to 56. We collected water samples during monthly cruises throughout the lagoon, and along the streams feeding the system, from April 1991 to March 1992. Nutrients and other water quality parameters exhibited great spatial and temporal variations. Mass balance calculations indicate large amounts of anthropogenic nutrient inputs. The data indicate that the lagoon currently is oligotrophic but is in a state of transition to become a mesotrophic system. Molar dissolved inorganic nitrogen:dissolved inorganic phosphorus (DIN/DIP) varied between 2.2:1 and 659:1 with a volume-weighted average of 22:1. The high DIN/DIP ratio contrasts with that found in nearby lagoons, suggesting that phytoplankton primary production is limited by phosphorus in Lagoa de Araruama. The major loss of DIP is apparently driven by biological assimilation and diagenic reactions in the sediments. Calculations indicate that the lagoon is slightly net autotrophic at +0.9 mol C m -2 yr -1. This suggests that the biomass of the primary producers is restricted by phosphorus availability. Phosphorus retention in the sediment and the hypersaline state of the lagoon prevent changes in autotrophic communities and the formation of eutrophic conditions.

  13. Mitochondrial and nuclear genetic variation across calving lagoons in Eastern North Pacific gray whales (Eschrichtius robustus).

    Science.gov (United States)

    Alter, S Elizabeth; Ramirez, Sergio Flores; Nigenda, Sergio; Ramirez, Jorge Urbán; Bracho, Lorenzo Rojas; Palumbi, Stephen R

    2009-01-01

    Accurate knowledge of population structure in cetaceans is critical for preserving and managing breeding habitat, particularly when habitat is not uniformly protected. Most eastern gray whales return to their major breeding range each winter along the Pacific coast of Baja California, Mexico, concentrating in 3 major calving lagoons, but it is unknown whether genetic differences exist between lagoons. Previous photo-identification studies and genetic studies suggest that gray whales may return to their natal lagoons to breed, potentially resulting in the buildup of genetic differences. However, an earlier genetic study used only one genetic marker and did not include samples from Bahia Magdalena, a major calving lagoon not currently designated as a wildlife refuge. To expand on this previous study, we collected genetic data from the mitochondrial control region (442 bp) and 9 microsatellite markers from 112 individuals across all 3 major calving lagoons. Our data suggest that migration rates between calving lagoons are high but that a small but significant departure from panmixia exists between Bahia Magdalena and Laguna San Ignacio (Fisher's Exact test, P 10% per generation). In addition, microsatellite data showed evidence of a severe population bottleneck. Eastern gray whales are still recovering from the impacts of whaling on their breeding grounds, and these populations should be protected and monitored for future genetic changes.

  14. Inhibition of microbial metabolism in anaerobic lagoons by selected sulfonamides, tetracyclines, lincomycin, and tylosin tartrate

    Science.gov (United States)

    Loftin, Keith A.; Henny, Cynthia; Adams, Craig D.; Surampali, Rao; Mormile, Melanie R.

    2005-01-01

    Antibiotics are used to maintain healthy livestock and to promote weight gain in concentrated animal feed operations. Antibiotics rarely are metabolized completely by livestock and, thus, are often present in livestock waste and in waste-treatment lagoons. The introduction of antibiotics into anaerobic lagoons commonly used for swine waste treatment has the potential for negative impacts on lagoon performance, which relies on a consortium of microbes ranging from fermentative microorganisms to methanogens. To address this concern, the effects of eight common veterinary antibiotics on anaerobic activity were studied. Anaerobic microcosms, prepared from freshly collected lagoon slurries, were amended with individual antibiotics at 10 mg/L for the initial screening study and at 1, 5, and 25 mg/L for the dose-response study. Monitored metabolic indicators included hydrogen, methane, and volatile fatty acid concentrations as well as chemical oxygen demand. The selected antibiotics significantly inhibited methane production relative to unamended controls, thus indicating that antibiotics at concentrations commonly found in swine lagoons can negatively impact anaerobic metabolism. Additionally, historical antibiotic usage seems to be a potential factor in affecting methane production. Specifically, less inhibition of methane production was noted in samples taken from the lagoon with a history of multiple-antibiotic use.

  15. Inhibition of microbial metabolism in anaerobic lagoons by selected sulfonamides, tetracyclines, lincomycin, and tylosin tartrate.

    Science.gov (United States)

    Loftin, Keith A; Henny, Cynthia; Adams, Craig D; Surampali, Rao; Mormile, Melanie R

    2005-04-01

    Antibiotics are used to maintain healthy livestock and to promote weight gain in concentrated animal feed operations. Antibiotics rarely are metabolized completely by livestock and, thus, are often present in livestock waste and in waste-treatment lagoons. The introduction of antibiotics into anaerobic lagoons commonly used for swine waste treatment has the potential for negative impacts on lagoon performance, which relies on a consortium of microbes ranging from fermentative microorganisms to methanogens. To address this concern, the effects of eight common veterinary antibiotics on anaerobic activity were studied. Anaerobic microcosms, prepared from freshly collected lagoon slurries, were amended with individual antibiotics at 10 mg/L for the initial screening study and at 1, 5, and 25 mg/L for the dose-response study. Monitored metabolic indicators included hydrogen, methane, and volatile fatty acid concentrations as well as chemical oxygen demand. The selected antibiotics significantly inhibited methane production relative to unamended controls, thus indicating that antibiotics at concentrations commonly found in swine lagoons can negatively impact anaerobic metabolism. Additionally, historical antibiotic usage seems to be a potential factor in affecting methane production. Specifically, less inhibition of methane production was noted in samples taken from the lagoon with a history of multiple-antibiotic use.

  16. 2009 SWFWMD Topographic Lidar: Peace River South (Florida)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — SWFWMD regularly uses digital topographic information to support regulatory, land management and acquisition, planning, engineering and habitat restoration projects....

  17. An update on the fish composition (Teleostei of the coastal lagoons of the Restinga de Jurubatiba National Park and the Imboassica Lagoon, northern Rio de Janeiro State

    Directory of Open Access Journals (Sweden)

    Fabio Di Dario

    Full Text Available AIM: We present an update on the composition of the fish species of the Restinga de Jurubatiba National Park and the Imboassica Lagoon, in the northern portion of Rio de Janeiro State, based on collecting efforts of almost two decades, historical museum records, and a review of the literature. METHODS: Specimens were collected using a variety of techniques, mostly between 1994 and 2012, and were fixed with the use of a 10% solution of formalin and subsequently stored in 70% alcohol solution. All specimens examined are deposited in the fish collections of the Núcleo em Ecologia e Desenvolvimento Socioambiental de Macaé, Universidade Federal do Rio de Janeiro (NPM, and Museu Nacional, Universidade Federal do Rio de Janeiro (MNRJ. Continental (freshwater fishes and some marine or estuarine species frequently collected were regarded as Resident, whereas marine species collected only sporadically were regarded as Occasional. Possible associations between the orientation of the lagoons and the composition of Resident fishes were explored through a Correspondence Analysis (CA. RESULTS: A total of 100 species, belonging to 19 orders and 41 families of the Teleostei were recorded. When both Resident and Occasional species are considered, families Carangidae and Engraulidae, with nine and eight species respectively, are the most representative. When only Resident species are considered, the Gerreidae and Gobiidae, both with seven species, are the most representative families. The Imboassica Lagoon, with 76 species, has the highest species richness among lagoons included in this study. A total of 81 species were recorded in the Restinga de Jurubatiba National Park, a number two times higher than reported on previous studies. An identification key, including 57 Resident species, is also presented. CONCLUSIONS: Parallel lagoons were characterized by a small group of continental species presumably of marine ancestry (Secondary Division, while marine species

  18. Levels of Platinum Group Metals in Selected Species (Sarotherodon melanotheron, Chonophorus lateristriga, Macrobrachium vollenhovenii and Crassostrea tulipa in Some Estuaries and Lagoons Along the Coast of Ghana

    Directory of Open Access Journals (Sweden)

    D. K. Essumang

    2010-01-01

    Full Text Available The use of some biota as bioindicators of heavy metal pollution has been demonstrated as particularly adequate due to their capacity of bioconcentration. This study evaluated the levels of platinum group metals (PGMs in some selected species along the coastal belt of Ghana, using the neutron activation analysis (NAA method. The result was processed to evaluate pollution indices in order to map the distribution of the metals in those species in the lagoons and estuaries along the costal belt of Ghana. The analysis showed significant levels of all PGMs in blackchin tilapia (Sarotherodon melanotheron Cichlidae, brown goby (Chonophorus lateristriga Gobiidae, shrimp (Macrobrachium vollenhovenii Palaemonidae, and mangrove oysters (Crassostrea tulipa Ostreidae in the lagoons and river Pra estuary. However, the oysters showed an elevated mean concentration of 0.13 μ/g (dry weight Pd. From the pollution indices, most of the sampling sites registered mean contamination factor (CF values between 1.20 and 3.00 for Pt, Pd, and Rh. The pollution load index (PLI conducted also gave an average pollution index between 0.79 and 2.37, indicating progressive contamination levels. The results revealed that anthropogenic sources, industrial and hospital effluent, etc., together with vehicular emissions, could be the contributing factors to the deposition of PGMs along the Ghanaian coast.

  19. 210Pb and 137Cs as chronometers for salt marsh accretion in the Venice Lagoon - links to flooding frequency and climate change

    International Nuclear Information System (INIS)

    Bellucci, L.G.; Frignani, M.; Cochran, J.K.; Albertazzi, S.; Zaggia, L.; Cecconi, G.; Hopkins, H.

    2007-01-01

    Five salt marsh sediment cores from different parts of the Venice Lagoon were studied to determine their depositional history and its relationship with the environmental changes occurred during the past ∼100 years. X-radiographs of the cores show no disturbance related to particle mixing. Accretion rates were calculated using a constant flux model applied to excess 210 Pb distributions in the cores. The record of 137 Cs fluxes to the sites, determined from 137 Cs profiles and the 210 Pb chronologies, shows inputs from the global fallout of 137 Cs in the late 1950s to early 1960s and the Chernobyl accident in 1986. Average accretion rates in the cores are comparable to the long-term average rate of mean sea level rise in the Venice Lagoon (∼0.25 cm y -1 ) except for a core collected in a marsh presumably affected by inputs from the Dese River. Short-term variations in accretion rate are correlated with the cumulative frequency of flooding, as determined by records of Acqua Alta, in four of the five cores, suggesting that variations in the phenomena causing flooding (such as wind patterns, storm frequency and NAO) are short-term driving forces for variations in marsh accretion rate

  20. 210Pb and 137Cs as chronometers for salt marsh accretion in the Venice Lagoon - links to flooding frequency and climate change.

    Science.gov (United States)

    Bellucci, L G; Frignani, M; Cochran, J K; Albertazzi, S; Zaggia, L; Cecconi, G; Hopkins, H

    2007-01-01

    Five salt marsh sediment cores from different parts of the Venice Lagoon were studied to determine their depositional history and its relationship with the environmental changes occurred during the past approximately 100 years. X-radiographs of the cores show no disturbance related to particle mixing. Accretion rates were calculated using a constant flux model applied to excess (210)Pb distributions in the cores. The record of (137)Cs fluxes to the sites, determined from (137)Cs profiles and the (210)Pb chronologies, shows inputs from the global fallout of (137)Cs in the late 1950s to early 1960s and the Chernobyl accident in 1986. Average accretion rates in the cores are comparable to the long-term average rate of mean sea level rise in the Venice Lagoon ( approximately 0.25 cm y(-1)) except for a core collected in a marsh presumably affected by inputs from the Dese River. Short-term variations in accretion rate are correlated with the cumulative frequency of flooding, as determined by records of Acqua Alta, in four of the five cores, suggesting that variations in the phenomena causing flooding (such as wind patterns, storm frequency and NAO) are short-term driving forces for variations in marsh accretion rate.

  1. {sup 210}Pb and {sup 137}Cs as chronometers for salt marsh accretion in the Venice Lagoon - links to flooding frequency and climate change

    Energy Technology Data Exchange (ETDEWEB)

    Bellucci, L.G. [Istituto di Scienze Marine - Sede di Bologna - Geologia Marina, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna (Italy)], E-mail: luca.bellucci@ismar.cnr.it; Frignani, M. [Istituto di Scienze Marine - Sede di Bologna - Geologia Marina, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna (Italy); Cochran, J.K. [Marine Sciences Research Center, Stony Brook University, Stony Brook, New York 11794-5000, NY (United States); Albertazzi, S. [Istituto di Scienze Marine - Sede di Bologna - Geologia Marina, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna (Italy); Zaggia, L. [Istituto di Scienze Marine, Consiglio Nazionale delle Ricerche - S. Polo 1364, 30125 Venezia (Italy); Cecconi, G. [Consorzio Venezia Nuova - S. Croce 505, 30135 Venezia (Italy); Hopkins, H. [Marine Sciences Research Center, Stony Brook University, Stony Brook, New York 11794-5000, NY (United States)

    2007-10-15

    Five salt marsh sediment cores from different parts of the Venice Lagoon were studied to determine their depositional history and its relationship with the environmental changes occurred during the past {approx}100 years. X-radiographs of the cores show no disturbance related to particle mixing. Accretion rates were calculated using a constant flux model applied to excess {sup 210}Pb distributions in the cores. The record of {sup 137}Cs fluxes to the sites, determined from {sup 137}Cs profiles and the {sup 210}Pb chronologies, shows inputs from the global fallout of {sup 137}Cs in the late 1950s to early 1960s and the Chernobyl accident in 1986. Average accretion rates in the cores are comparable to the long-term average rate of mean sea level rise in the Venice Lagoon ({approx}0.25 cm y{sup -1}) except for a core collected in a marsh presumably affected by inputs from the Dese River. Short-term variations in accretion rate are correlated with the cumulative frequency of flooding, as determined by records of Acqua Alta, in four of the five cores, suggesting that variations in the phenomena causing flooding (such as wind patterns, storm frequency and NAO) are short-term driving forces for variations in marsh accretion rate.

  2. Resistance and resilience of ecosystem descriptors and properties to dystrophic events: a study case in a Mediterranean lagoon

    OpenAIRE

    Basset, Alberto; Barbone, Enrico; Rosati, Ilaria; Vignes, Fabio; Breber, Paolo; Specchiulli, Antonietta; D'Adamo, Raffaele; Renzi, Monia; Focardi, Silvano; Ungaro, Nicola; Pinna, Maurizio

    2013-01-01

    Mediterranean lagoons are naturally exposed, during the dry season, to dystrophic and hypoxic events determining dis-equilibrium conditions along temporal and spatial scales, which are linked to metabolism and life cycle of the biotic components. In summer 2008, Lesina lagoon (SE Italian coastline) was interested by a geographically localized dystrophic crisis which affected up to 8% of the total lagoon surface. Temporal dynamics of principal descriptors of abiotic (water, sediment) and bioti...

  3. Three Dinophyceae from Clipperton Island lagoon (eastern Pacific Ocean), including a description of Peridiniopsis cristata var. tubulifera var. nov.

    OpenAIRE

    Coute, Alain; Perrette, Catherine; Chomerat, Nicolas

    2012-01-01

    Clipperton Island is a small French coral atoll in the eastern Pacific Ocean, which has been rarely investigated because of its remote location and difficult access. There is little scientific information on this ecosystem and only a few microalgae have been reported from the lagoon. To date, only one dinoflagellate taxon, Peridiniopsis cristata, is known to inhabit the lagoon. During an expedition in 2005 to study the lagoon and the surrounding oceanic waters of Clipperton Island, a further ...

  4. CISOCUR - Hydrodynamic circulation in the Curonian Lagoon inferred through stable isotope measurements and numerical modelling

    Science.gov (United States)

    Umgiesser, Georg; Razinkovas-Baziukas, Arturas; Barisevičiūtė, Ruta; Baziukė, Dalia; Ertürk, Ali; Gasiūnaitė, Jovita; Gulbinskas, Saulius; Lubienė, Irma; Maračkinaite, Jurgita; Petkuvienė, Jolita; Pilkaitytė, Renata; Ruginis, Tomas; Zemlys, Petras; Žilius, Mindaugas

    2013-04-01

    The spatial pattern of the hydrodynamic circulation of the Curonian lagoon, the largest European coastal lagoon, is still little understood. In absence of automatic current registration data all the existing models relied mostly on such data as water levels leaving high level of uncertainty. Here we present CISOCUR, a new project financed by the European Social Fund under the Global Grant measure. The project applies a new methodology that uses the carbon stable isotope (SI) ratio of C12 and C13 that characterize different water sources entering the lagoon and may be altered by internal kinetic processes. Through the tracing of these isotope ratios different water masses can be identified. This gives the possibility to validate several hypotheses of water circulation and validate hydrodynamic models. In particular it will be possible to 1) trace water masses entering the lagoon through the Nemunas and the Klaipeda strait; 2) test the hypothesis of sediment transport mechanisms inside the lagoon; 3) evaluate the importance of physical forcing on the lagoon circulation. The use of a hydrodynamic finite element model, coupled with the SI method, will allow for a realistic description of the transport processes inside the Curonian lagoon. So the main research goal is to apply the stable isotope tracers and a finite element model to determine the circulation patterns in the Curonian lagoon. Overall, the project will develop according to 4 main phases: 1) A pilot study to measure the isotope composition of different carbon compounds (dissolved and suspended) in different water bodies that feed water into the central lagoon. Through this pilot study the optimal study sites for the seasonal campaign will be identified as well. 2) Seasonal field campaigns in the monitoring stations identified in phase 1 to measure the carbon isotope ratio. 3) Development of a model that describes the kinetics of carbon isotopes and its transformation. 4) Application of a hydrodynamic model

  5. Groundwater dependence of coastal lagoons: The case of La Pletera salt marshes (NE Catalonia)

    Science.gov (United States)

    Menció, A.; Casamitjana, X.; Mas-Pla, J.; Coll, N.; Compte, J.; Martinoy, M.; Pascual, J.; Quintana, X. D.

    2017-09-01

    Coastal wetlands are among the most productive ecosystems of the world, playing an important role in coastal defense and wildlife conservation. These ecosystems, however, are usually affected by human activities, which may cause a loss and degradation of their ecological status, a decline of their biodiversity, an alteration of their ecological functioning, and a limitation of their ecosystem services. La Pletera salt marshes (NE Spain) are located in a region mainly dominated by agriculture and tourism activities. Part of these wetlands and lagoons has been affected by an incomplete construction of an urban development and in this moment is the focus of a Life+ project, whose aim is to restore this protected area. Several studies have analyzed the role of hydrological regime in nutrients, phytoplankton and zooplankton in this area, however, the role of groundwater was never considered as a relevant factor in the lagoon dynamics, and its influence is still unknown. In this study, the hydrogeological dynamics in La Pletera salt marshes has been analyzed, as a basis to set sustainable management guidelines for this area. In order to determine their dependence on groundwater resources, monthly hydrochemical (with major ions and nutrients) and isotopic (δ18OH2O and δD) campaigns have been conducted, from November 2014 to October 2015. In particular, groundwater from six wells, surface water from two nearby streams and three permanent lagoons, and sea water was considered in these surveys. Taking into account the meteorological data and the water levels in the lagoons, the General Lake Model has been conducted to determine, not only evaporation and rainfall occurring in the lagoons, but also the total inflows and outflows. In addition, the Gonfiantini isotopic model, together with equilibrium chemical-speciation/mass transfer models, has been used to analyze the evaporation and the physicochemical processes affecting the lagoons. Results show that during the dry

  6. Environmental quality of transitional waters: the lagoon of Venice case study.

    Science.gov (United States)

    Micheletti, C; Gottardo, S; Critto, A; Chiarato, S; Marcomini, A

    2011-01-01

    The health status of European aquatic environments, including transitional waters such as coastal lagoons, is regulated by the Water Framework Directive (WFD), which requires the classification of the water bodies' environmental quality and the achievement of a good ecological status by 2015. In the Venice lagoon, a transitional water body located in the northeastern part of Italy, the achievement of a good ecological status is hampered by several anthropogenic and natural pressures, such as sediment and water chemical contamination, and sediment erosion. In order to evaluate the lagoon's environmental quality according to the WFD (i.e. 5 quality classes, from High to Bad), an integrated Weight-of-Evidence methodology was developed and applied to classify the quality of the lagoon water bodies, integrating biological, physico-chemical, chemical, ecotoxicological, and hydromorphological data (i.e. Lines of Evidence, LOE). The quality assessment was carried out in two lagoon habitat typologies (previously defined on the basis of morphological, sediment, and hydrodynamic characteristics) which were selected taking into account the ecological gradient from sea to land, and the differences in anthropogenic pressure and contamination levels. The LOE classification was carried out by using indicators scored by comparing site specific conditions to reference conditions measured in lagoon reference sites, or provided by local, national or European regulations (e.g. Environmental Quality Standards, EQS, for chemicals). Finally, the overall quality status for each water body was calculated by a probabilistic approach, i.e. by reporting the final result as the frequency distribution of quality classes. The developed procedure was applied by using data and information concerning selected LOE and collected from monitoring programs and research studies carried out in the last 15 years in the lagoon of Venice. A set of sampling stations characterized by spatially and temporally

  7. 78 FR 43881 - Florida Petroleum Reprocessors Site, Davie, Broward County, Florida; Notice of Settlement

    Science.gov (United States)

    2013-07-22

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL9836-2; CERCLA-04-2013-3758] Florida Petroleum Reprocessors... entered into a settlement with Jap. Tech, Inc. concerning the Florida Petroleum Reprocessors Site located.... Painter. Submit your comments by Site name Florida Petroleum Reprocesssors Site by one of the following...

  8. Charles River

    Science.gov (United States)

    Information on the efforts of the US EPA, the Commonwealth of Massachusetts, the municipalities within the Charles River Watershed and nongovernmental organizations to improve the water quality of the Charles River.

  9. Zooplankton of an urban coastal lagoon: composition and association with environmental factors and summer fish kill

    Directory of Open Access Journals (Sweden)

    Leonardo C. e Souza

    2011-06-01

    Full Text Available Zooplankton may be regarded as a sensitive tool for monitoring environmental variations in coastal lagoons due to their ability to immediately react to changes in the water column trophic features and salinity levels. As a coastal lagoon with a broad history of anthropic influence, Rodrigo de Freitas Lagoon (Rio de Janeiro, Brazil is widely used for water sports and artisanal fishing. The present study aimed to expand the knowledge base about zooplankton in the Rodrigo de Freitas Lagoon by assessing the composition and time-spatial distribution of the major zooplankton groups. Samples were collected fortnightly from at four distinct sampling points August 2001 to July 2002. At each point, salinity, temperature, dissolved oxygen and water transparency were measured. During the study period, the lagoon behaved as an spatially homogeneous environment in what regards the abiotic variables. However, all these variables showed significant differences along the time, mainly related to seasonality (air temperature and rainy and dry periods. The zooplankton community showed low taxonomic richness, with the predominance of species commonly found in coastal lagoons, especially with mesohaline conditions, as well as those found in estuaries. An interesting fact was the rise in zooplankton abundance at all sampling points right after a fish kill event. Such increase was caused mainly by the Brachionus plicatilis O.F. Müller 1786 species. Thus, the zooplankton community was affected by physical and chemical factors, mainly by the dissolved oxygen decline event and variations in the influx of seawater into the lagoon. In addition, phytoplankton availability and fish predation pressure were suggested as important regulating factors of the zooplankton community.

  10. Hydrologic characteristics of lagoons at San Juan, Puerto Rico, during an October 1974 tidal cycle

    Science.gov (United States)

    Gómez-Gómez, Fernando; Ellis, S.R.

    1983-01-01

    Flow and water-quality changes were studied during a period of intense rainfall in the San Juan Lagoon system. The study covered a 25-hour period beginning 0900 hours 22 October, 1974. Precipitation during the study period averaged 70 millimeters. Sampling stations were located at Boca de Cangrejos, the main ocean outlet; Canal Pinones between Laguna de Pinones and Laguna La Torrecilla; Canal Suarez between Laguna San Jose, connects to Laguna La Torrecilla; and Cano de Martin Pena between Laguna San Jose and Bahia de San Juan. In addition water-elevation recording gages were installed at each lagoon. Water samples from the canal stations were analyzed for organic carbon, nitrogen and phosphorus species, and suspended sediment. Specific-conductance measurements were used with the chemical data to estimate the runoff contributions of nutrients. Runoff into the lagoon, system during the study period was about 2.8 million cubic meters, or about 70 percent of the average precipitation. The runoff contributed chemical loadings to the lagoons of 95,000 kilograms total-organic carbon; 2,700 kilograms of total phosphorus; and 10,000 kilograms of total Khjeldhal nitrogen. A comparison with a prior study during which there was no significant rain, show that dry-period loadings are less than 10 percent of the wet-period loadings. At the end of the study period the system had not reached equilibrium, and the lagoons retained 80 percent of the water inflows from 50 to 90 percent of the chemical loads. Nearly 95 percent of the water outflows occurred at the Boca de Cangrejos sea outlet. The three lagoons and interconnecting canals form a very complex hydraulic system that is difficult to study using traditional techniques. A model of the system will facilitate management to improve the quality of water in the lagoons.

  11. Reconstruction of historic sea ice conditions in a sub-Arctic lagoon

    Science.gov (United States)

    Petrich, Chris; Tivy, Adrienne C.; Ward, David H.

    2014-01-01

    Historical sea ice conditions were reconstructed for Izembek Lagoon, Bering Sea, Alaska. This lagoon is a crucial staging area during migration for numerous species of avian migrants and a major eelgrass (Zostera marina) area important to a variety of marine and terrestrial organisms, especially Pacific Flyway black brant geese (Branta bernicla nigricans). Ice cover is a common feature of the lagoon in winter, but appears to be declining, which has implications for eelgrass distribution and abundance, and its use by wildlife. We evaluated ice conditions from a model based on degree days, calibrated to satellite observations, to estimate distribution and long-term trends in ice conditions in Izembek Lagoon. Model results compared favorably with ground observations and 26 years of satellite data, allowing ice conditions to be reconstructed back to 1943. Specifically, periods of significant (limited access to eelgrass areas) and severe (almost complete ice coverage of the lagoon) ice conditions could be identified. The number of days of severe ice within a single season ranged from 0 (e.g., 2001) to ≥ 67 (e.g., 2000). We detected a slight long-term negative trend in ice conditions, superimposed on high inter-annual variability in seasonal aggregate ice conditions. Based on reconstructed ice conditions, the seasonally cumulative number of significant or severe ice days correlated linearly with mean air temperature from January until March. Further, air temperature at Izembek Lagoon was correlated with wind direction, suggesting that ice conditions in Izembek Lagoon were associated with synoptic-scale weather patterns. Methods employed in this analysis may be transferable to other coastal locations in the Arctic.

  12. Spatial and temporal distribution of coloured dissolved organic matter in a hypertrophic freshwater lagoon

    Directory of Open Access Journals (Sweden)

    Diana Vaičiūtė

    2015-05-01

    Full Text Available A dataset of 224 Medium Resolution Imaging Spectrometer (MERIS full resolution satellite images were processed to retrieve the concentration of coloured dissolved organic matter (CDOM in a hypertrophic estuary (Curonian Lagoon, Lithuania and Russia. Images covered a period of 7 months, spanning from the ice melting (March to the late summer (September of 7 consecutive years (2005-2011. The aim of the study was to analyse the spatial and temporal variations of CDOM, by focusing on the main regulating factors (riverine discharge, sea-lagoon water exchange, water temperature, chlorophyll a, wind in a large estuary. The working hypothesis is that CDOM distribution may reveal distinct, site specific seasonal patterns. Our results demonstrated that CDOM concentrations at the whole lagoon level were elevated (1.5-4 m-1 and slightly but significantly higher in spring (1.50 m-1 on average compared to the summer (1.45 m-1 on average. This is due to very different flow of CDOM-rich freshwater from the main lagoon tributary in spring compared to summer. They also highlight macroscopic differences among areas within the lagoon, depending on season, suggesting a complex regulation of CDOM in this system. Significant factors explaining observed differences are the dilution of lagoon water with CDOM-poor brackish water, regeneration of large amounts of dissolved organic matter from sediments and combinations of uptake/release from phytoplankton. CDOM and its variations are understudied due to inherent methodological and analytical difficulties. However, this pool has a demonstrated relevant role in the biogeochemistry of aquatic environments. We speculate that the dissolved organic pool in the Curonian Lagoon has a mainly allochthonous origin in the high discharge period and an autochthonous origin in the summer, algal bloom period. Both positive and negative relationships between CDOM and phytoplankton suggest that pelagic microalgae may act as a source or as

  13. Hydrogeological effects of dredging navigable canals through lagoon shallows. A case study in Venice

    Directory of Open Access Journals (Sweden)

    P. Teatini

    2017-11-01

    Full Text Available For the first time a comprehensive investigation has been carried out to quantify the possible effects of dredging a navigable canal on the hydrogeological system underlying a coastal lagoon. The study is focused on the Venice Lagoon, Italy, where the port authority is planning to open a new 10 m deep and 3 km long canal to connect the city passenger terminal to the central lagoon inlet, thus avoiding the passage of large cruise ships through the historic center of Venice. A modeling study has been developed to evaluate the short (minutes, medium (months, and long (decades term processes of water and pollutant exchange between the shallow aquifer system and the lagoon, possibly enhanced by the canal excavation, and ship wakes. An in-depth characterization of the lagoon subsurface along the channel has supported the numerical modeling. Piezometer and sea level records, geophysical acquisitions, laboratory analyses of groundwater and sediment samples (chemical analyses and ecotoxicity testing, and the outcome of 3-D hydrodynamic and computational fluid dynamic (CFD models have been used to set up and calibrate the subsurface multi-model approach. The numerical outcomes allow us to quantify the groundwater volume and estimate the mass of anthropogenic contaminants (As, Cd, Cu, Cr, Hg, Pb, Se likely leaked from the nearby industrial area over the past decades, and released into the lagoon from the canal bed by the action of depression waves generated by ships. Moreover, the model outcomes help to understand the effect of the hydrogeological layering on the propagation of the tidal fluctuation and salt concentration into the shallow brackish aquifers underlying the lagoon bottom.

  14. Marshall Islands Fringing Reef and Atoll Lagoon Observations of the Tohoku Tsunami

    Science.gov (United States)

    Ford, Murray; Becker, Janet M.; Merrifield, Mark A.; Song, Y. Tony

    2014-12-01

    The magnitude 9.0 Tohoku earthquake on 11 March 2011 generated a tsunami which caused significant impacts throughout the Pacific Ocean. A description of the tsunami within the lagoons and on the surrounding fringing reefs of two mid-ocean atoll islands is presented using bottom pressure observations from the Majuro and Kwajalein atolls in the Marshall Islands, supplemented by tide gauge data in the lagoons and by numerical model simulations in the deep ocean. Although the initial wave arrival was not captured by the pressure sensors, subsequent oscillations on the reef face resemble the deep ocean tsunami signal simulated by two numerical models, suggesting that the tsunami amplitudes over the atoll outer reefs are similar to that in deep water. In contrast, tsunami oscillations in the lagoon are more energetic and long lasting than observed on the reefs or modelled in the deep ocean. The tsunami energy in the Majuro lagoon exhibits persistent peaks in the 30 and 60 min period bands that suggest the excitation of closed and open basin normal modes, while energy in the Kwajalein lagoon spans a broader range of frequencies with weaker, multiple peaks than observed at Majuro, which may be associated with the tsunami behavior within the more irregular geometry of the Kwajalein lagoon. The propagation of the tsunami across the reef flats is shown to be tidally dependent, with amplitudes increasing/decreasing shoreward at high/low tide. The impact of the tsunami on the Marshall Islands was reduced due to the coincidence of peak wave amplitudes with low tide; however, the observed wave amplitudes, particularly in the atoll lagoon, would have led to inundation at different tidal phases.

  15. Environmental Assessment for Airfield Safety and Drainage Improvements at Patrick Air Force Base, Florida

    Science.gov (United States)

    2011-12-22

    of Cocoa Beach, and covers approximately 2,000 acres bounded by the Atlantic Ocean on the east and the Banana River on the west. The PAFB airfield...significance for greenhouse gas emissions, but the Federal government recognizes the need to reduce energy consumption and shift to renewable and...Historical and Architectural Documentation Reports of Patrick Air Force Base, Cocoa Beach, Florida. U.S. Army Construction Engineering Research

  16. Reconstructing the migration patterns of late Pleistocene mammals from northern Florida, USA

    Science.gov (United States)

    Hoppe, Kathryn A.; Koch, Paul L.

    2007-11-01

    We used analyses of the strontium isotope ( 87Sr/ 86Sr) ratios of tooth enamel to reconstruct the migration patterns of fossil mammals collected along the Aucilla River in northern Florida. Specimens date to the late-glacial period and before the last glacial maximum (pre-LGM). Deer and tapir displayed low 87Sr/ 86Sr ratios that were similar to the ratios of Florida environments, which suggest that these taxa did not migrate long distance outside of the Florida region. Mastodons, mammoths, and equids all displayed a wide range of 87Sr/ 86Sr ratios. Some individuals in each taxon displayed low 87Sr/ 86Sr ratios that suggest they ranged locally, while other animals had high 87Sr/ 86Sr ratios that suggest they migrated long distances (> 150 km) outside of the Florida region. Mastodons were the only taxa from this region that provided enough well-dated specimens to compare changes in migration patterns over time. Pre-LGM mastodons displayed significantly lower 87Sr/ 86Sr ratios than late-glacial mastodons, which suggests that late-glacial mastodons from Florida migrated longer distances than their earlier counterparts. This change in movement patterns reflects temporal changes in regional vegetation patterns.

  17. The Life of a Sponge in a Sandy Lagoon.

    Science.gov (United States)

    Ilan, M; Abelson, A

    1995-12-01

    Infaunal soft-bottom invertebrates benefit from the presence of sediment, but sedimentation is potentially harmful for hard-bottom dwellers. Most sponges live on hard bottom, but on coral reefs in the Red Sea, the species Biemna ehrenbergi (Keller, 1889) is found exclusively in soft-bottom lagoons, usually in the shallowest part. This location is a sink environment, which increases the deposition of particulate organic matter. Most of the sponge body is covered by sediment, but the chimney-like siphons protrude from the sediment surface. The sponge is attached to the buried beach-rock, which reduces the risk of dislodgment during storms. Dye injected above and into the sediment revealed, for the first time, a sponge pumping interstitial water (rich with particles and nutrients) into its aquiferous system. Visual examination of plastic replicas of the aquiferous system and electron microscopical analysis of sponge tissue revealed that the transcellular ostia are mostly located on the buried surface of the sponge. The oscula, however, are located on top of the siphons; their elevated position and their ability to close combine to prevent the filtering system outflow from clogging. The transcellular ostia presumably remain open due to cellular mobility. The sponge maintains a large population of bacteriocytes, which contains bacteria of several different species. Some of these bacteria disintegrate, and may be consumed by the sponge.

  18. Fragrances as new contaminants in the Venice lagoon.

    Science.gov (United States)

    Vecchiato, Marco; Cremonese, Simone; Gregoris, Elena; Barbaro, Elena; Gambaro, Andrea; Barbante, Carlo

    2016-10-01

    Fragrance Materials (FMs) are omnipresent components of household and Personal Care Products (PCPs). In spite of their widespread use, little is known about their environmental occurrence. We selected 17 among the longest-lasting and most stable fragrance ingredients that are commercially available, namely: Amberketal, Ambrofix, Amyl Salicylate, Benzyl Salicylate, Bourgeonal, Dupical, Hexyl Salicylate, Isobutavan, Lemonile, Mefranal, Myraldene, Okoumal, Oranger Crystals, Pelargene, Peonile, Tridecene-2-Nitrile, Ultravanil. A new analytical method was developed to quantify FMs in water samples and it was applied to perform the first study about the distribution of these compounds in the surface waters of the city of Venice and its lagoon. Total FMs concentrations range from about 30ngL(-1) to more than 10μgL(-1) in polluted canals during the low tide. Sewage discharges were supposed to be the main sources of the selected FMs in the environment. Salicylates, oestrogenic and allergenic compounds, were in general the most abundant and widespread components. This study reports for the first time the detection of most of the selected FMs in surface waters and represent the first step to understand their environmental fate. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Archive of bathymetry data collected in South Florida from 1995 to 2015

    Science.gov (United States)

    Hansen, Mark Erik; DeWitt, Nancy T.; Reynolds, Billy J.

    2017-08-10

    DescriptionLand development and alterations of the ecosystem in south Florida over the past 100 years have decreased freshwater and increased nutrient flows into many of Florida's estuaries, bays, and coastal regions. As a result, there has been a decrease in the water quality in many of these critical habitats, often prompting seagrass die-offs and reduced fish and aquatic life populations. Restoration of water quality in many of these habitats will depend partly upon using numerical-circulation and sediment-transport models to establish water-quality targets and to assess progress toward reaching restoration targets. Application of these models is often complicated because of complex sea floor topography and tidal flow regimes. Consequently, accurate and modern sea-floor or bathymetry maps are critical for numerical modeling research. Modern bathymetry data sets will also permit a comparison to historical data in order to help assess sea-floor changes within these critical habitats. New and detailed data sets also support marine biology studies to help understand migratory and feeding habitats of marine life.This data series is a compilation of 13 mapping projects conducted in south Florida between 1995 and 2015 and archives more than 45 million bathymetric soundings. Data were collected primarily with a single beam sound navigation and ranging (sonar) system called SANDS developed by the U.S. Geological Survey (USGS) in 1993. Bathymetry data for the Estero Bay project were supplemented with the National Aeronautics and Space Administration's (NASA) Experimental Advanced Airborne Research Lidar (EAARL) system. Data from eight rivers in southwest Florida were collected with an interferometric swath bathymetry system. The projects represented in this data series were funded by the USGS Coastal and Marine Geology Program (CMGP), the USGS South Florida Ecosystem Restoration Project- formally named Placed Based Studies, and other non-Federal agencies. The purpose of

  20. Benthic Habitats of Estero Bay Area, Florida 1999 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data produced for the Florida Fish and Wildlife Conservation Commission's Florida Marine Research Institute (FMRI) in partnership with the South Florida Water...

  1. Benthic Habitats of Estero Bay Area, Florida 1999 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data produced for the Florida Fish and Wildlife Conservation Commission's Florida Marine Research Institute (FMRI) in partnership with the South Florida Water...

  2. Benthic Habitats of Estero Bay Area, Florida 1999 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data produced for the Florida Fish and Wildlife Conservation Commission's Florida Marine Research Institute (FMRI) in partnership with the South Florida Water...

  3. Distribution and ecological relevance of fine sediments in organic-enriched lagoons: The case study of the Cabras lagoon (Sardinia, Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Magni, P. [CNR-IAMC, National Research Council - Institute for Coastal Marine Environment Localita Sa Mardini, Torregrande, 09072 Oristano (Italy); International Marine Centre, Localita Sa Mardini, Torregrande, 09072 Oristano (Italy)], E-mail: paolo.magni@iamc.cnr.it; De Falco, G. [CNR-IAMC, National Research Council - Institute for Coastal Marine Environment Localita Sa Mardini, Torregrande, 09072 Oristano (Italy); International Marine Centre, Localita Sa Mardini, Torregrande, 09072 Oristano (Italy); Como, S. [International Marine Centre, Localita Sa Mardini, Torregrande, 09072 Oristano (Italy); Casu, D. [Dip. di Botanica ed Ecologia vegetale, Universita di Sassari, 07100 Sassari (Italy); Floris, A. [Dip. di Zoologia e Genetica evoluzionistica, Universita di Sassari, 07100 Sassari (Italy); Petrov, A.N. [Institute of Biology of the Southern Seas NASU, 99011 Sevastopol (Ukraine); Castelli, A. [Dip. di Biologia, Universita di Pisa, 56126 Pisa (Italy); Perilli, A. [CNR-IAMC, National Research Council - Institute for Coastal Marine Environment Localita Sa Mardini, Torregrande, 09072 Oristano (Italy); International Marine Centre, Localita Sa Mardini, Torregrande, 09072 Oristano (Italy)

    2008-03-15

    In organic-enriched sedimentary systems, like many Mediterranean coastal lagoons, a detailed analysis of sediment grain size composition and partitioning within the muds is crucial to investigate sedimentological trends related to both hydrodynamic energy and basin morphology. In these systems, sediment dynamics are particularly important because the partitioning and transport of fine sediments can strongly influence the redistribution and accumulation of large amounts of organic matter, and consequently the distribution of benthic assemblages and the trophic status and functioning of a lagoon. Nevertheless, studies on benthic-sediment relationships have been based mainly on a rather coarse analysis of sediment grain size features. In muddy systems, however, this approach may impede a proper evaluation of the relationships and effects of the distribution of fine sediment and organic matter on the biotic benthic components. Here we show that the distribution of sedimentary organic matter (OM) and total organic carbon (TOC) in the Cabras lagoon (Sardinia, Italy) can be explained (i.e., predicted) as a function of a nonlinear increase in the amount of the cohesive fraction of sediments ({<=}8 {mu}m grain size particles) and that this fraction strongly influences the structure, composition and distribution of macrobenthic assemblages. Even in such a homogeneously muddy system, characterized by 'naturally' occurring impoverished communities, impaired benthic assemblages were found at {<=}8 {mu}m, OM, TOC contents of about 77%, 11% and 3.5%, respectively. A review of studies conducted in Mediterranean coastal lagoons highlighted a lack of direct integrated analysis of sediment features and the biotic components. We suggest that, especially in organic-enriched coastal lagoons, monitoring programs should primarily investigate and consider the cohesive fraction of sediments in order to allow a better assessment of benthic-sediment relationships and ecological

  4. Water Withdrawals, Use, and Trends in Florida, 2005

    Science.gov (United States)

    Marella, Richard L.

    2009-01-01

    In 2005, the total amount of water withdrawals in Florida was estimated at 18,359 million gallons per day (Mgal/d). Saline water accounted for 11,486 Mgal/d (63 percent), and freshwater accounted for 6,873 Mgal/d (37 percent). Groundwater accounted for 4,247 Mgal/d (62 percent) of freshwater withdrawals, and surface water accounted for the remaining 2,626 Mgal/d (38 percent). Surface water accounted for nearly all (99.9 percent) saline-water withdrawals. An additional 660 Mgal/d of reclaimed wastewater was used in Florida during 2005. The largest amount of freshwater was withdrawn from Palm Beach County, and the largest amount of saline water was withdrawn from Pasco County. Fresh groundwater provided drinking water (public supplied and self-supplied) for 16.19 million people (90 percent of Florida's population), and fresh surface water provided drinking water for 1.73 million people (10 percent). The majority of groundwater withdrawals (nearly 60 percent) in 2005 was obtained from the Floridan aquifer system which is present throughout the entire State. The majority of fresh surface-water withdrawals (59 percent) came from the southern Florida hydrologic unit subregion and is associated with Lake Okeechobee and the canals in the Everglades Agricultural Area of Glades, Hendry, and Palm Beach Counties, as well as the Caloosahatchee River and its tributaries in the agricultural areas of Collier, Glades, Hendry, and Lee Counties. Overall, agricultural irrigation accounted for 40 percent of the total freshwater withdrawals (ground and surface), followed by public supply with 37 percent. Public supply accounted for 52 percent of groundwater withdrawals, followed by agricultural self-supplied (31 percent), ommercial-industrial-mining self-supplied (8.5 percent), recreational irrigation and domestic self-supplied (4 percent each), and power generation (0.5 percent). Agricultural self-supplied accounted for 56 percent of fresh surface-water withdrawals, followed by power

  5. Water withdrawals, use, and trends in Florida, 2010

    Science.gov (United States)

    Marella, Richard L.

    2014-01-01

    In 2010, the total amount of water withdrawn in Florida was estimated to be 14,988 million gallons per day (Mgal/d). Saline water accounted for 8,589 Mgal/d (57 percent) and freshwater accounted for 6,399 Mgal/d (43 percent). Groundwater accounted for 4,166 Mgal/d (65 percent) of freshwater withdrawals, and surface water accounted for the remaining 2,233 Mgal/d (35 percent). Surface water accounted for nearly all (99.9 percent) saline-water withdrawals. An additional 659 Mgal/d of reclaimed wastewater was used in Florida during 2010. Freshwater withdrawals were greatest in Palm Beach County (707 Mgal/d), and saline-water withdrawals were greatest in Hillsborough County (1,715 Mgal/d). Fresh groundwater provided drinking water (public supplied and self-supplied) for 17.33 million people (92 percent of Florida’s population), and fresh surface water provided drinking water for 1.47 million people (8 percent). The statewide public-supply gross per capita use for 2010 was 134 gallons per day, whereas the statewide public-supply domestic per capita use was 85 gallons per day. The majority of groundwater withdrawals (almost 62 percent) in 2010 were obtained from the Floridan aquifer system, which is present throughout most of the State. The majority of fresh surface-water withdrawals (56 percent) came from the southern Florida hydrologic unit subregion and is associated with Lake Okeechobee and the canals in the Everglades Agricultural Area of Glades, Hendry, and Palm Beach Counties, as well as the Caloosahatchee River and its tributaries in the agricultural areas of Collier, Glades, Hendry, and Lee Counties. Overall, agricultural irrigation accounted for 40 percent of the total freshwater withdrawals (ground and surface), followed by public supply with 35 percent. Public supply accounted for 48 percent of groundwater withdrawals, followed by agricultural self-supplied (34 percent), commercial-industrial-mining self-supplied (7 percent), recreational

  6. Impact of mussel bioengineering on fine-grained sediment dynamics in a coastal lagoon: A numerical modelling investigation

    Science.gov (United States)

    Forsberg, Pernille L.; Lumborg, Ulrik; Bundgaard, Klavs; Ernstsen, Verner B.

    2017-12-01

    Rødsand lagoon in southeast Denmark is a non-tidal coastal lagoon. It is home to a wide range of marine flora and fauna and part of the Natura 2000 network. An increase in turbidity through elevated levels of suspended sediment concentration (SSC) within the lagoon may affect the ecosystem health due to reduced light penetration. Increasing SSC levels within Rødsand lagoon could be caused by increasing storm intensity or by a sediment spill from dredging activities west of the lagoon in relation to the planned construction of the Fehmarnbelt fixed link between Denmark and Germany. The aim of the study was to investigate the impact of a mussel reef on sediment import and SSC in a semi-enclosed lagoon through the development of a bioengineering modelling application that makes it possible to include the filtrating effect of mussels in a numerical model of the lagoonal system. The numerical implementation of an exterior mussel reef generated a reduction in the SSC in the vicinity of the reef, through the adjacent inlet and in the western part of the lagoon. The mussel reef reduced the sediment import to Rødsand lagoon by 13-22% and reduced the SSC within Rødsand lagoon by 5-9% depending on the filtration rate and the reef length. The results suggest that the implementation of a mussel reef has the potential to relieve the pressure of increasing turbidity levels within a semi-enclosed lagoonal system. However, further assessment and development of the bioengineering application and resulting ecosystem impacts are necessary prior to actual implementation.

  7. Biodiversity patterns of macrophyte and macroinvertebrate communities in two lagoons of Western Greece.

    Science.gov (United States)

    Fyttis, G.; Reizopoulou, S.; Papastergiadou, E.

    2012-04-01

    Aquatic macrophytes and benthic macroinvertebrates were studied seasonally (Spring, Autumn, Summer) between the years 2009 - 2011 in two coastal lagoons (Kotychi and Prokopos) located in Peloponnese, Greece, in order to investigate spatial and temporal biodiversity trends related to hydrological processes (degree of confinement, nitrates, phosphates, chl-a, total suspended materials, light irradiance, pH, salinity, temperature and dissolved oxygen). Kotychi lagoon presents a better communication with the sea, while Prokopos has a high degree of confinement. Both ecosystems seasonally receive freshwater input from streams. The submerged aquatic macrophytes constituted a major component of the ecosystems studied. In total, 22 taxa of aquatic macrophytes (angiosperms and macroalgae), 16 taxa for Kotychi (2 Rhodophyta, 8 Chlorophyta, 5 Magnoliophyta, 1 Streptophyta) and 14 taxa for Prokopos (1 Rhodophyta, 5 Chlorophyta, 5 Magnoliophyta, 3 Streptophyta) were found. Ruppia cirrhosa, and Potamogeton pectinatus were dominant in both lagoons. Kotychi lagoon was also dominated by Zostera noltii and Prokopos by Zannichellia pallustris ssp. pedicellata, while the biomass of aquatic species peaked during the summer periods, in both lagoons. The total number of macroinvertebrates found in the lagoons was 28 taxa for Kotychi and 19 for Prokopos. Chironomidae were dominant in both lagoons, while Kotychi was also dominated by Lekanesphaera monodi and Monocorophium insidiosum, and Prokopos by Ostracoda and Lekanesphaera monodi. Benthic diversity ranged from 1.33 to 2.57 in Kotychi and from 0.67 to 2.48 in Prokopos. Species richness, diversity, and abundance of benthic macroinvertebrates were strongly related to aquatic vegetation and to the degree of communication with the marine environment. Moreover, species richness and abundance of both macrophytes and macroinvertebrates were mainly dependent on depth, temperature, pH and concentration of total suspended materials (TSM). Results

  8. [Species and size composition of fishes in Barra de Navidad lagoon, Mexican central Pacific].

    Science.gov (United States)

    González-Sansón, Gaspar; Aguilar-Betancourt, Consuelo; Kosonoy-Aceves, Daniel; Lucano-Ramírez, Gabriela; Ruiz-Ramírez, Salvador; Flores-Ortega, Juan Ramón; Hinojosa-Larios, Angel; de Asís Silva-Bátiz, Francisco

    2014-03-01

    Coastal lagoons are considered important nursery areas for many coastal fishes. Barra de Navidad coastal lagoon (3.76km2) is important for local economy as it supports tourism development and artisanal fisheries. However, the role of this lagoon in the dynamics of coastal fish populations is scarcely known. Thus, the objectives of this research were: to characterize the water of the lagoon and related weather conditions, to develop a systematic list of the ichthyofauna, and to estimate the proportion of juveniles in the total number of individuals captured of most abundant species. Water and fish samples were collected between March 2011 and February 2012. Physical and chemical variables were measured in rainy and dry seasons. Several fishing gears were used including a cast net, beach purse seine and gillnets of four different mesh sizes. Our results showed that the lagoon is most of the time euhaline (salinity 30-40ups), although it can be mixopolyhaline (salinity 18-30ups) during short periods. Chlorophyll and nutrients concentrations suggested eutrophication in the lagoon. Mean water temperature changed seasonally from 24.9 degrees C (April, high tide) to 31.4 degrees C (October, low tide). Considering ichthyofauna species, a total of 36 448 individuals of 92 species were collected, 31 of them adding up to 95% of the total of individuals caught. Dominant species were Anchoa spp. (44.6%), Diapterus peruvianus (10.5%), Eucinostomus currani (8.1%), Cetengraulis mysticetus (7.8%), Mugil curema (5.2%) and Opisthonema libertate (4.5%). The lagoon is an important juvenile habitat for 22 of the 31 most abundant species. These included several species of commercial importance such as snappers (Lutjanus argentiventris, L. colorado and L. novemfasciatus), snook (Centropomus nigrescens) and white mullet (Mugil curema). Other four species seem to use the lagoon mainly as adults. This paper is the first contribution on the composition of estuarine ichthyofauna in Jalisco

  9. Estimation of dynamic load of mercury in a river with BASINS-HSPF model

    Science.gov (United States)

    Ying Ouyang; John Higman; Jeff Hatten

    2012-01-01

    Purpose Mercury (Hg) is a naturally occurring element and a pervasive toxic pollutant. This study investigated the dynamic loads of Hg from the Cedar-Ortega Rivers watershed into the Lower St. Johns River (LSJR), Florida, USA, using the better assessment science integrating point and nonpoint sources (BASINS)-hydrologic simulation program - FORTRAN (HSPF) model....

  10. Fluoride tracer test for the performance analysis of a basin used as a lagooning pre-treatment facility in a WTP.

    Science.gov (United States)

    Ruffino, Barbara

    2015-07-01

    The water treatment plant (WTP) of the city of Torino (NW Italy), which treats about 40 · 10(6) m(3)/year of raw water from Po river, has a 15-ha basin used as a lagooning pre-treatment facility. Since the efficiency of the lagooning process in the removal of pollutants from raw water depends on the internal hydrodynamics of the basin, the hydraulic performance of the basin was studied by combining the results of a stimulus-response tracer test with the monitoring of the tracer (fluoride) concentration throughout the basin at different times. The outcomes of the test demonstrated that the system was efficiently mixed and could be assimilated to a continuous stirred reactor presenting no flow anomalies, with an actual mean residence time (RT) of 12.7 days, compared with a nominal RT of 18 days. This assured that dissolved contaminants (such as fluoride) coming from the river were efficiently diluted before entering the WTP. The axial dispersion coefficient calculated from the RT distribution was approximately 47,300 m(2)/day. Three of the most popular formulae developed for the calculation of the axial dispersion coefficient provided results spreading over three orders of magnitude, thus showing their limitations. Finally, because of the width extent of the basin and the characteristics of its inflow, the 1-D advection-dispersion model failed in predicting the tracer concentration values in time at the outlet channel. On the contrary, the analytical solution of the 2-D advection-dispersion model proved to be suitable to fit the tracer concentration data over time at the outlet channel but it failed in describing the tracer distribution throughout the basin on the monitoring dates.

  11. Do lagoons near concentrated animal feeding operations promote nitrous oxide supersaturation?

    International Nuclear Information System (INIS)

    Makris, Konstantinos C.; Sarkar, Dibyendu; Andra, Syam S.; Bach, Stephan B.H.; Datta, Rupali

    2009-01-01

    Animal wastewater lagoons nearby concentrated animal feeding operations (CAFOs) represent the latest tendency in global animal farming, severely impacting the magnitude of greenhouse gas emissions, including nitrous oxide (N 2 O). We hypothesized that lagoon wastewater could be supersaturated with N 2 O as part of incomplete microbial nitrification/denitrification processes, thereby regulating the N 2 O partitioning in the gaseous phase. The objectives of this study were: (i) to investigate the magnitude of dissolved N 2 O concentrations in the lagoon; and (ii) to determine the extent to which supersaturation of N 2 O occurs in wastewater lagoons. Dissolved N 2 O concentrations in the wastewater samples were high, ranging from 0.4 to 40.5 μg N 2 O mL -1 . Calculated dissolved N 2 O concentrations from the experimentally measured partition coefficients were much greater than those typically expected in aquatic systems ( 2 O mL -1 ). Knowledge of the factors controlling the magnitude of N 2 O supersaturation could potentially bridge mass balance differences between in situ measurements and global N 2 O models. - Supersaturation of nitrous oxide may occur in lagoons near concentrated animal feeding operations.

  12. Comprehensive assessment of hormones, phytoestrogens, and estrogenic activity in an anaerobic swine waste lagoon

    Science.gov (United States)

    Yost, Erin E.; Meyer, Michael T.; Dietze, Julie E.; Meissner, Benjamin M.; Williams, Mike; Worley-Davis, Lynn; Lee, Boknam; Kullman, Seth W.

    2013-01-01

    In this study, the distribution of steroid hormones, phytoestrogens, and estrogenic activity was thoroughly characterized within the anaerobic waste lagoon of a typical commercial swine sow operation. Three independent rounds of sampling were conducted in June 2009, April 2010, and February 2011. Thirty-seven analytes in lagoon slurry and sludge were assessed using LC/MS-MS, and yeast estrogen screen was used to determine estrogenic activity. Of the hormone analytes, steroidal estrogens were more abundant than androgens or progesterone, with estrone being the predominant estrogen species. Conjugated hormones were detected only at low levels. The isoflavone metabolite equol was by far the predominant phytoestrogen species, with daidzein, genistein, formononetin, and coumestrol present at lower levels. Phytoestrogens were often more abundant than steroidal estrogens, but contributed minimally towards total estrogenic activity. Analytes were significantly elevated in the solid phases of the lagoon; although low observed log KOC values suggest enhanced solubility in the aqueous phase, perhaps due to dissolved or colloidal organic carbon. The association with the solid phase, as well as recalcitrance of analytes to anaerobic degradation, results in a markedly elevated load of analytes and estrogenic activity within lagoon sludge. Overall, findings emphasize the importance of adsorption and transformation processes in governing the fate of these compounds in lagoon waste, which is ultimately used for broadcast application as a fertilizer.

  13. Diversity of resource use and property rights in Tam Giang Lagoon, Vietnam

    Directory of Open Access Journals (Sweden)

    Ta Thi Thanh Huong

    2011-02-01

    Full Text Available Since the early 1990s, aquaculture has become the most important livelihood activity in Tam Giang Lagoon, Vietnam. The aquaculture boom has reduced the available water area for mobile gear fishers, polarized different user-groups, created resource conflicts, and increased pressures on the lagoon systems. Aquaculture in the lagoon is governed by both customary and legal rights. The objective of this paper is to explore the diversity of resource use and the complexity of property rights in one of the villages located in the lagoon. The paper emphasizes the linkages between changes in commons institutions and changes in resource use and property rights. First, the political and socio-economic changes in Vietnam are examined as well as how they have influenced traditional commons institutions and lagoon resource management in the village. Second, the linkages between common institutions and the diversity of property rights are analyzed. Particular attention is given to the analysis of different types of resource use associated with "bundle of rights" and the diversity of property rights regimes in the village.

  14. Studies of lagoon ash from Sarawak to assess the impact on the environment

    Energy Technology Data Exchange (ETDEWEB)

    Prabir Kumar Kolay; Harwant Singh [University Malaysia Sarawak, Sarawak (Malaysia). Dept. of Civil Engineering

    2010-02-15

    Coal utilization, mainly in thermal power plants, has increased significantly from 4.2 to 13 million tonnes within 2000 to 2005, which resulted in the production of approximately 2 million tonnes of coal ash in Malaysia. Of this only a small percentage is used as a cement ingredient, in concrete industry, as a fill material, etc. and with the rest of the amount being disposed in ash ponds or lagoons. If the lagoons are not properly designed with a landfill liner or if there is spillage from the ash pond, the toxic heavy metal present in coal ash can result in the contamination of the subsurface soil and the ground water. The concentration of heavy metals or trace elements in coal residues depends on the composition of a particular parent coal and the bulk utilization of lagoon ash for various purposes requires a complete characterization of the ash. Hence, this paper analyzes the coal ash for its trace element content and characterizes mainly physical, chemical, mineralogical, morphological and thermal properties of the lagoon ash from a local coal based thermal power plant from Sarawak, Malaysia. The results also indicated that, the concentration of some trace elements is quite high from the environmental perspective in this particular lagoon ash. 43 refs., 4 figs., 4 tabs.

  15. 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.

  16. Assessing pollution in a Mediterranean lagoon using acid volatile sulfides and estimations of simultaneously extracted metals.

    Science.gov (United States)

    Zaaboub, Noureddine; Helali, Mohamed Amine; Martins, Maria Virgínia Alves; Ennouri, Rym; Béjaoui, Béchir; da Silva, Eduardo Ferreira; El Bour, Monia; Aleya, Lotfi

    2016-11-01

    Bizerte Lagoon is a southern Mediterranean semi-enclosed lagoon with a maximum depth of 12 m. After assessing sediment quality, the authors report on the physicochemical characteristics of the lagoon's surface sediment using SEM (simultaneously extracted metals) and AVS (acid volatile sulfides) as proxies. Biogeochemical tools are used to investigate the environmental disturbance at the water-sediment interface by means of SEM and AVS to seek conclusions concerning the study area's pollution status. Results confirm accumulation of trace elements in sediment. The use of the SEM-AVS model with organic matter in sediment (ƒOC) confirms possible bioavailability of accumulated trace elements, especially Zn, in the southern part of the lagoon, with organic matter playing an important role in SEM excess correction to affirm a nontoxic total metal sediment state. Individual trace element toxicity is dependent on the bioavailable fraction of SEM Metal on sediment, as is the influence of lagoon inflow from southern water sources on element bioavailability. Appropriate management strategies are highly recommended to mitigate any potential harmful effects on health from this heavy-metal-based pollution.

  17. Investigation of residence time and groundwater flux in Venice Lagoon: comparing radium isotope and hydrodynamic models.

    Science.gov (United States)

    Rapaglia, John; Ferrarin, Christian; Zaggia, Luca; Moore, Willard S; Umgiesser, Georg; Garcia-Solsona, Ester; Garcia-Orellana, Jordi; Masqué, Pere

    2010-07-01

    The four naturally-occurring isotopes of radium were coupled with a previously evaluated hydrodynamic model to determine the apparent age of surface waters and to quantify submarine groundwater discharge (SGD) into the Venice Lagoon, Italy. Mean apparent age of water in the Venice Lagoon was calculated using the ratio of 224Ra to 228Ra determined from 30 monitoring stations and a mean pore water end member. Average apparent age was calculated to be 6.0 d using Ra ratios. This calculated age was very similar to average residence time calculated for the same period using a hydrodynamic model (5.8 d). A mass balance of Ra was accomplished by quantifying each of the sources and sinks of Ra in the lagoon, with the unknown variable being attributed to SGD. Total SGD were calculated to be 4.1 +/- 1.5, 3.8 +/- 0.7, 3.0 +/- 1.3, and 3.5 +/- 1.0 x 10(10) L d(-1) for (223,224,226, 228)Ra, respectively, which are an order of magnitude larger than total mean fluvial discharge into the Venice Lagoon (3.1 x 10(9) L d(-1)). The SGD as a source of nutrients in the Venice Lagoon is also discussed and, though significant to the nutrient budget, is likely to be less important as the dominant control on SGD is recirculated seawater rather than freshwater. 2009 Elsevier Ltd. All rights reserved.

  18. Investigation of residence time and groundwater flux in Venice Lagoon: comparing radium isotope and hydrodynamical models

    International Nuclear Information System (INIS)

    Rapaglia, John; Ferrarin, Christian; Zaggia, Luca; Moore, Willard S.; Umgiesser, Georg; Garcia-Solsona, Ester; Garcia-Orellana, Jordi; Masque, Pere

    2010-01-01

    The four naturally-occurring isotopes of radium were coupled with a previously evaluated hydrodynamic model to determine the apparent age of surface waters and to quantify submarine groundwater discharge (SGD) into the Venice Lagoon, Italy. Mean apparent age of water in the Venice Lagoon was calculated using the ratio of 224 Ra to 228 Ra determined from 30 monitoring stations and a mean pore water endmember. Average apparent age was calculated to be 6.0 d using Ra ratios. This calculated age was very similar to average residence time calculated for the same period using a hydrodynamic model (5.8 d). A mass balance of Ra was accomplished by quantifying each of the sources and sinks of Ra in the lagoon, with the unknown variable being attributed to SGD. Total SGD were calculated to be 4.1 ± 1.5, 3.8 ± 0.7, 3.0 ± 1.3, and 3.5 ± 1.0 x 10 10 L d -1 for 223,224,226,228 Ra, respectively, which are an order of magnitude larger than total mean fluvial discharge into the Venice Lagoon (3.1 x 10 9 L d -1 ). The SGD as a source of nutrients in the Venice Lagoon is also discussed and, though significant to the nutrient budget, is likely to be less important as the dominant control on SGD is recirculated seawater rather than freshwater.

  19. Pan-European management of coastal lagoons: A science-policy-stakeholder interface perspective

    Science.gov (United States)

    Lillebø, Ana I.; Stålnacke, Per; Gooch, Geoffrey D.; Krysanova, Valentina; Bielecka, Małgorzata

    2017-11-01

    The main objective of the work carried out in the scope of a three years collaborative research project was to develop science-based strategies and a decision support framework for the integrated management of coastal lagoons and their catchments and, in this context, to enhance connectivity between research and policymaking. In this paper our main objective is to share the lessons learned from the innovative methodology used throughout the project. To achieve the proposed objectives, the multidisciplinary scientific knowledge in the project team was combined and integrated with the knowledge and views of local stakeholders of four selected European coastal lagoons, using a three step participatory approach. With this innovative approach, which included the usage of eco-hydrological and water quality-modelling tools, the team developed and analyzed integrated scenarios of possible economic development and environmental impacts in four European lagoons and their catchments. These scenarios were presented and discussed with stakeholders, giving rise to management recommendations for each case study lagoon. Results show that some management options might be transferrable to other European lagoons having similar climatic, geophysical and socio-economic settings. In management terms, the project output provides a set of policy guidelines derived from the different analyses conducted and proposes initiatives concerning management implementation in a local-regional-national-European setting.

  20. Seagrasses and sediment response to changing physical forcing in a coastal lagoon

    Directory of Open Access Journals (Sweden)

    J. Figueiredo da Silva

    2004-01-01

    Full Text Available The Ria de Aveiro is an estuary–coastal lagoon system connected to the Atlantic Ocean by a channel with a cross-sectional area that, for more than a century, has increased steadily, partly because of dredging over the last 50 years. Local ocean tides, with amplitudes of up to 3 m, are today transmitted to the lagoon by the single, engineered inlet channel and propagate to the end of the lagoon channels as a damped progressive wave. The increase in tidal amplitude with time has affected the lagoon ecosystem and the water has become more saline. Seagrass beds are important indicators of ecosystem change; until 1980, much of the lagoon bed was covered by seagrasses (Zostera, Ruppia, Potamogeton, which were collected in large quantities for use in agriculture. After 1960, the harvesting declined and the seagrass beds became covered in sediment, so that the area of seagrasses decreased substantially despite the decline in the quantity collected. The change in the pattern of seagrass populations can be related to changes in the physical forcing associated with increased tidal wave penetration. This has, in turn, induced transport and redistribution of coarser, sandy sediment and increased re-suspension and turbidity in the water column. However, the initiating cause for this ecosystem change was dredging, which, since the 1950s, has been used increasingly to widen and deepen the channels of the system.

  1. A review on the availability of ecological data aiming new researches in Peri Lagoon

    Directory of Open Access Journals (Sweden)

    Maurício Mello Petrucio

    2008-06-01

    Full Text Available The increase in population as well as the water resource demand has been intensifying the human influence in Peri Lagoon basin. A review on the availability of data concerning the ecology of Peri Lagoon was made, aiming at the development of new researches to understand the functioning of this ecosystem. This information can contribute to the elaboration of a conservation proposal and sustainable use of the Lagoon in the future. High cyanobacteria density (Cylindrospermopsis raciborskii was detected in the Lagoon waters, which happens to be a risky situation for the ecosystem’s health and consequently for the population. The review highlights a lack of available information about the dynamics, functioning and structure of aquatic communities, as well as their relationships with the surrounding area and the infl uence of abiotic factors. Series of continuum data with respect to time are also considered to be lacking. Educational, political and social practices in environmental conservation are necessary, aiming at the management and sustainable use of Peri Lagoon basin. These practices will guarantee water resource quality and availability for the current and future generations.

  2. Trace metals in water and sediments from Ologe Lagoon, southwestern Nigeria

    International Nuclear Information System (INIS)

    Yusuf, K.A.; Osibanjo, O.

    2006-01-01

    The concentrations of trace metals in water and sediment samples from Ologe lagoon located in southwestern Nigeria were investigated. The lagoon is a source of water for domestic, transportation and fishing activities. The water quality characteristics for a period of two years (January, 1997 - November, 1998), and the speciation of metals in the lagoon sediments were evaluated. The lagoon water quality characteristics, with respect to heavy metal contamination, were compared with global averages for freshwater and international water quality standards for drinking water. All elements except iron, were well within the safety limits. Sequential extraction techniques were used to establish the association of the total concentrations of Zn, Cu, Pb, Cd and Mn in the sediment samples with their contents as exchangeable, carbonates, Fe/Mn oxides, and organic and residual fractions. The concentrations of trace metals in the whole sediments were generally below the world-wide background levels. When compared to a number of sediment quality guidelines, the concentrations of trace metals were found to be below the level considered to have the potential to cause biological effects. Pb and Cd were extracted from the residual fraction at values greater than 50%. The metals that were most easily extractable in the samples analyzed were Mn and Zn, which posed the highest risk to water contamination. The low level of industrialization in the study area has kept the lagoon relatively free from heavy metal contamination. (author)

  3. Atmospheric Deposition of Inorganic Elements and Organic Compounds at the Inlets of the Venice Lagoon

    Directory of Open Access Journals (Sweden)

    E. Morabito

    2014-01-01

    Full Text Available The Venice Lagoon is subjected to long-range transport of contaminants via aerosol from the near Po Valley. Moreover, it is an area with significant local anthropogenic emissions due to the industrial area of Porto Marghera, the urban centres, and the glass factories and with emissions by ships traffic within the Lagoon. Furthermore, since 2005, the Lagoon has also been affected by the construction of the MOSE (Modulo Sperimentale Elettromeccanico—Electromechanical Experimental Module mobile dams, as a barrier against the high tide. This work presents and discusses the results from chemical analyses of bulk depositions, carried out in different sites of the Venice Lagoon. Fluxes of pollutants were also statistically analysed on PCA with the aim of investigating the spatial variability of depositions and their correlation with precipitations. Fluxes of inorganic pollutants depend differently on precipitations, while organic compounds show a more seasonal trend. The statistical analysis showed that the site in the northern Lagoon has lower and almost homogeneous fluxes of pollutants, while the other sites registered more variable concentrations. The study also provided important information about the annual trend of pollutants and their evolution over a period of about five years, from 2005 to 2010.

  4. Preliminary study for treatment methodology establishment of liquid waste containing uranium in refining facility lagoon

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Jik; Lee, Kune Woo; Won, Hui Jun; Ahn, Byung Gil; Shim, Joon Bo

    1999-12-01

    The preliminary study which establishes the treatment methodology of the sludge waste containing uranium in the conversion facility lagoon was performed. The property of lagoon liquid waste such as the initial water content, the density including radiochemical analysis results were obtained using the samples taken from the lagoon. The objective of this study is to provide some basically needed materials for selection of the most proper lagoon waste treatment methodology by reviewing the effective processes and methods for minimizing the secondary waste resulting from the treatment and disposition of large amount of radioactive liquid waste according to the facility closing. The lagoon waste can be classified into two sorts, such as supernatant and precipitate. The supernatants contain uranium less than 5 ppm and their water content are about 35 percent. Therefore, supernatants are solutions composed of mainly salt components. However, the precipitates have lots of uranium compound contained in the coagulation matrix, and are formed as two kinds of crystalline structures. The most proper method minimizing the secondary waste would be direct drying and solidification of the supernatants and precipitates after separation of them by filtering. (author)

  5. Integrated Approach to Transboundary Waters Management, such as a Rivermouth and a Lagoon

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.H.; Lee, B.K.; Yoo, H.J. [Korea Environment Institute, Seoul (Korea); Kang, D.S.; Nam, J.H. [Korea Maritime Institute, Seoul (Korea)

    2001-12-01

    Estuaries and coastal lagoons (estuarine environments) are typical transitional ecosystems between land and sea, where sea water is mixed with fresh water. It is well known that estuarine environments are very valuable ecosystems because of their unique ecological functions and geographical features, as well as socioeconomic values. These precious estuaries, however, have become severely deteriorated and damaged by human activities through watersheds and intensive coastal developments. In this respect, this study aims to develop integrated management strategies for protection, improvement, and restoration of estuarine environments that would support sustainable uses of those precious natural resources. This study found that regardless of their ecological value, estuaries and coastal lagoons in Korea have deteriorated due to a lack of appropriate management systems and imprudent development and utilization. Furthermore, considering the fact that destruction of the estuaries has been caused by national development projects, the study urges the Korean government to change its development-oriented policies on estuaries and coastal lagoons to more sustainable ones so that future generations may enjoy the benefits from healthy natural estuaries and coastal lagoons. The Korean government, thus, needs to declare that it will no longer promote any development-oriented policy that might destroy valuable estuaries and coastal lagoons, in preparing for the 2002 WSSD which will be held in South Africa in 2002. (author). 175 refs., 72 figs., 95 tabs.

  6. Saltwater intrusion monitoring in Florida

    Science.gov (United States)

    Prinos, Scott T.

    2016-01-01

    Florida's communities are largely dependent on freshwater from groundwater aquifers. Existing saltwater in the aquifers, or seawater that intrudes parts of the aquifers that were fresh, can make the water unusable without additional processing. The quality of Florida's saltwater intrusion monitoring networks varies. In Miami-Dade and Broward Counties, for example, there is a well-designed network with recently constructed short open-interval monitoring wells that bracket the saltwater interface in the Biscayne aquifer. Geochemical analyses of water samples from the network help scientists evaluate pathways of saltwater intrusion and movement of the saltwater interface. Geophysical measurements, collected in these counties, aid the mapping of the saltwater interface and the design of monitoring networks. In comparison, deficiencies in the Collier County monitoring network include the positioning of monitoring wells, reliance on wells with long open intervals that when sampled might provide questionable results, and the inability of existing analyses to differentiate between multiple pathways of saltwater intrusion. A state-wide saltwater intrusion monitoring network is being planned; the planned network could improve saltwater intrusion monitoring by adopting the applicable strategies of the networks of Miami-Dade and Broward Counties, and by addressing deficiencies such as those described for the Collier County network.

  7. Sexual Harassment Policies in Florida School Districts.

    Science.gov (United States)

    Rienzo, Barbara A.; Moore, Michele Johnson

    1998-01-01

    Investigated the extent to which Florida's school districts complied with the Florida Department of Education's (FDOE) recommendations for addressing sexual harassment in schools. Surveys of district equity coordinators and analysis of policies indicated that most districts approved sexual harassment policies incorporating many FDOE…

  8. Transitions in ancient inland freshwater resource management in Sri Lanka affect biota and human populations in and around coastal lagoons.

    Science.gov (United States)

    Dahdouh-Guebas, F; Hettiarachchi, S; Lo Seen, D; Batelaan, O; Sooriyarachchi, S; Jayatissa, L P; Koedam, N

    2005-03-29

    The increasing anthropogenic pressure on natural environments results in impacts that affect tropical forest areas and their biodiversity. Adverse impacts on terrestrial and oceanic environments often compound in the intertidal area, where mangrove forest ecosystems thrive. In tropical coastal areas of many developing countries where people depend on wood and other mangrove forest products and services, forest degradation leads to socioeconomic problems. At the same time, increasing freshwater needs in these areas are expected to cause additional problems. On the basis of remote sensing and ground truthing complemented by colonial archival material from the Dutch East India Company (1602-1800), we report that changes to the historic system of inland freshwater management have increased dramatically in recent times. Hydrological changes, such as interbasin transfers, have resulted in a qualitative ecological and socioeconomic degradation in three coastal lagoons in southern Sri Lanka. Variations in river hydrology have caused changes in the areas suitable as mangrove habitat and, thus, have resulted in an altered distribution. However, increases in mangrove area can mask the degradation of the site in terms of floristic composition, significance of the species, and biodiversity (this effect is termed "cryptic ecological degradation"). It is important that such changes be carefully monitored to ensure biological and socioeconomic sustainability.

  9. Organic matter composition in the sediment of three Brazilian coastal lagoons: district of Macaé, Rio de Janeiro (Brazil).

    Science.gov (United States)

    Zink, Klaus-Gerhard; Furtado, André L S; Casper, Peter; Schwark, Lorenz

    2004-03-01

    Freshwater lagoons comprise important coastal ecosystems and natural buffers between urbanized land areas and open ocean in the Rio de Janeiro State, Brazil. Studies of sediment and water chemistry, zooplankton and bacterial communities to assess the extent of anthropogenic disturbance are available. Here we contribute with an organic-geochemical approach supplemented by some microbiological aspects to complete the characterization of these lagoonal ecosystems. Bulk organic matter and extractable lipids (aliphatic hydrocarbons, alcohols and fatty acids, sterols) were investigated from two locations per lagoon: at the seaward site and landward ends - and at two depth intervals (0-3 and 3-6 cm) per site. Urbanized Imboacica Lagoon received increased anthropogenic input over the most recent years represented by the topmost 3 cm of sediment, whereas deeper sediment layers are less affected by human influence. Eutrophication or nutrient availability favored enhanced algal/cyanobacterial growth. In remote Cabiúnas and Comprida Lagoons pristine conditions are preserved. Organic matter from vascular plants dominates (chain length of free lipids up to C36), which is exceptionally well preserved by acidic lagoonal waters. Differentiation between landward and seaward sites in these two lagoons is less well established due to much smaller surface/volume to catchment ratios. No anthropogenic influences are yet detectable in sediments of Cabiúnas and Comprida Lagoons.

  10. Wind effects on prey availability: How northward migrating waders use brackish and hypersaline lagoons in the Sivash, Ukraine

    NARCIS (Netherlands)

    Verkuil, Yvonne I.; Koolhaas, Anita; Van Der Winden, Jan

    1993-01-01

    Large numbers of waders migrating northward in spring use the Sivash, a large system of shallow, brackish and hypersaline lagoons in the Black Sea and Azov Sea region (Ukraine). The bottoms of these lagoons are often uncovered by the wind. Hence, for waders the time and space available for feeding

  11. Controls of Sediment Nitrogen Dynamics in Tropical Coastal Lagoons

    Science.gov (United States)

    Enrich-Prast, Alex; Figueiredo, Viviane; Esteves, Francisco de Assis; Nielsen, Lars Peter

    2016-01-01

    Sediment denitrification rates seem to be lower in tropical environments than in temperate environments. Using the isotope pairing technique, we measured actual denitrification rates in the sediment of tropical coastal lagoons. To explain the low denitrification rates observed at all study sites (<5 μmol N2 m-2 h-1), we also evaluated potential oxygen (O2) consumption, potential nitrification, potential denitrification, potential anammox, and estimated dissimilatory nitrate (NO3-) reduction to ammonium (NH4+; DNRA) in the sediment. 15NO3- and 15NH4+ conversion was measured in oxic and anoxic slurries from the sediment surface. Sediment potential O2 consumption was used as a proxy for overall mineralization activity. Actual denitrification rates and different potential nitrogen (N) oxidation and reduction processes were significantly correlated with potential O2 consumption. The contribution of potential nitrification to total O2 consumption decreased from contributing 9% at sites with the lowest sediment mineralization rates to less than 0.1% at sites with the highest rates. NO3- reduction switched completely from potential denitrification to estimated DNRA. Ammonium oxidation and nitrite (NO2-) reduction by potential anammox contributed up to 3% in sediments with the lowest sediment mineralization rates. The majority of these patterns could be explained by variations in the microbial environments from stable and largely oxic conditions at low sediment mineralization sites to more variable conditions and the prevalences of anaerobic microorganisms at high sediment mineralization sites. Furthermore, the presence of algal and microbial mats on the sediment had a significant effect on all studied processes. We propose a theoretical model based on low and high sediment mineralization rates to explain the growth, activity, and distribution of microorganisms carrying out denitrification and DNRA in sediments that can explain the dominance or coexistence of DNRA and

  12. Migration Rate Of Tidal Meanders: Inferences From The Venice Lagoon

    Science.gov (United States)

    Finotello, A.; D'Alpaos, A.; Ghinassi, M.; Lanzoni, S.; Marani, M.; Rinaldo, A.

    2015-12-01

    Meandering channels are ubiquitous features of tidal landscapes. However, despite their fundamental role on the eco-morphodynamic evolution of these landscapes, tidal meanders have received less attention when compared to their fluvial counterparts. Improving current understanding of tidal meander migration, a largely-examined topic in fluvial landscapes, is a key step to highlight analogies and differences between tidal and fluvial cases. The migration of about 400 meander bends, belonging to 40 salt-marsh channels in the Northern Venice Lagoon (Italy), from 1968 to nowadays, has been investigated by means of both a classical method in fluvial frameworks and new procedure. Similarities with fluvial meanders occur, although important difference also emerge. Meanders cutting through the San Felice marsh follow the relationship between cartesian length and channel width, typical of meanders developed within different settings. However, meander migration rates proved to be smaller than those characterizing fluvial meanders. Indeed, the analysis of meander migration suggests a mean migration rate of about 0.10 m/year, consistent with the few data available in the literature. As for the fluvial case, the maximum-potential migration rate (i.e. the envelope curve of the relationship between migration rate and bend radius, both divided by channel width) reaches a maximum for radius-over-width ratio included between 2 and 3, regardless of the considered method. Nevertheless, the new-proposed method allows us to provide a more objective and continuous characterization. By using this new procedure, the channel curvature has finally been Fourier-analyzed, confirming the importance of even harmonics along the curvature spectrum. A correlation between migration rates and dominant harmonics seems to drive the evolution of tidal meanders and might represent a key-feature to distinguish them from their fluvial counterparts.

  13. Distribution to heavy metals in sediments of the Venice Lagoon: The role of the industrial area

    International Nuclear Information System (INIS)

    Frignani, M.; Bellucci, L.G.; Ravanelli, M.; Paolucci, D.

    1999-01-01

    The Venice Lagoon has been heavily polluted both from diffuse and direct sources. It has been recently established that the atmospheric delivery of contaminants to the lagoon can be very significant in zones far from direct sources, but the influence of the industrial area of Porto Marghera, though widely recognized, has not been entirely described and quantified. In order to assess the temporal and spatial variability of metal pollution, and to better understand the contribution of the industrial channels as sources of contaminants, in May 1996 we sampled 18 stations in the lagoon and 9 in the channels of the industrial area of Porto Marghera. At each site a short core, 10 cm long, was taken and immediately extruded to obtain 4 slices 2-2.5 cm thick. Sediment samples have been analysed for As, Cd, Pb, and Zn after acid extraction

  14. 210Pb and 210Po in Venice Lagoon Biota and their contribution to population dose

    International Nuclear Information System (INIS)

    Jia Guogang; Rosamilia, S.; Blasi, M.; Sansone, U.; Belli, M.; Sepulcri, D.; Bidoli, P.

    2002-01-01

    Phosphogypsum is a by-product resulting from the processes applied in phosphoric acid or phosphate fertilizer production. The phosphate ore used in these chemical processes contains the naturally occurring radioactive materials U, and Th, along with their decay products. Large volumes of solid waste products were discharged from a phosphoric acid production plant on the edge of the Venice lagoon (Italy). Water, suspended matter, and biota were monitored in the Venice lagoon, since this aquatic environment can be considered to represent the final area of deposition for the radionuclides transported from inland. The present paper reports data on the activity concentrations of 210 Po and 210 Pb determined in biota living in the lagoon, and an estimation of the contribution to internal dose to man from the ingestion of food originating in the investigated area. (orig.)

  15. Lagoon Sediment Dynamics: A Coupled Model to Study a Medium-Term Silting of Tidal Channels

    Directory of Open Access Journals (Sweden)

    Marco Petti

    2018-04-01

    Full Text Available The silting of tidal channels is a natural process that affects several shallow lagoons and makes it difficult to navigate, requiring regular maintenance interventions. This phenomenon is the result of the complex non-linear interaction between tidal currents and wave motion. In this work, the morphodynamic evolution of the Marano and Grado lagoon is investigated by means of a two-dimensional horizontal (2DH morphological-hydrodynamic and a spectral coupled model. An innovative procedure to reproduce the overall bathymetric changes in the medium term and, in particular, the volumes deposited inside channels, is presented. An average year with a sequence of winds and tides acting over that time was reconstructed, carrying out cross correlation techniques and spectral analyses of measured data. The predicted morphological evolution matches the annual dredged volumes in the lagoon critical branches and shows the distribution of erosion and deposition of cohesive sediments according to spatially variable values of critical shear stress.

  16. Effect of Coastal Waves on Hydrodynamics in One-Inlet Coastal Nador Lagoon, Morocco

    Directory of Open Access Journals (Sweden)

    Jeyar Mohammed

    2015-01-01

    Full Text Available Nador lagoon is a coastal system connected to the sea through a narrow and shallow inlet; understanding its hydraulic performance is required for its design and operation. This paper investigates the hydrodynamic impacts of the whole lagoon due to tidal waves using a numerical approach. In this study we use a two-dimensional, depth-averaged hydrodynamic model based on so-called shallow water equations solved within triangular mesh by a developed efficient finite volume method. The method was calibrated and validated against observed data and applied to analyze and predict water levels, tidal currents, and wind effects within the lagoon. Two typical idealized scenarios were investigated: tide only and tide with wind forcing. The predicted sea surface elevations and current speeds have been presented during a typical tidal period and show correct physics in different scenarios.

  17. Shallow gas accumulation in sediments of the Patos Lagoon, Southern Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Weschenfelder, Jair; Corrrea, Iran C.S.; Pereira, Carla M.; Vasconcellos, Vinicius E.B. de [Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil). Inst. de Geociencias; Aliotta, Salvador [Instituto Argentino de Oceanografia Complejo CRIBABB, Bahia Blanca (Argentina)

    2006-07-15

    A high resolution seismic survey was conducted in the Patos Lagoon, southern Brazil, aboard of the research vessel LARUS of the Fundacao Universidade Federal do Rio Grande (FURG). Around 400 km of 3.5 k Hz seismic profiles were collected, which provided acoustic signals of good penetration depth and resolution. Seismic anomalies, including turbidity and pocket gas, revealed that gas-charged sediments are common in several areas of the lagoon. The gas accumulations in the Patos Lagoon are controlled by the spatial distribution of the sedimentary facies. Either in 'curtains' or in 'acoustic turbid zones', the main gas accumulations occur in areas with paleotopographic lows related to fluvial channels and valleys developed in the Rio Grande do Sul coastal plain during regressive/transgressive events of the Quaternary. (author)

  18. Florida Atlantic Coast Telemetry (FACT) Array: A Working Partnership

    Science.gov (United States)

    Scheidt, Douglas; Ault, Erick; Ellis, Robert D.; Gruber, Samuel; Iafrate, Joseph; Kalinowsky, Chris; Kessel, Steven; Reyier, Eric; Snyder, David; Watwood, Stephanie; hide

    2015-01-01

    The Florida Atlantic Coast Telemetry (FACT) Array is a collaborative partnership of researchers from 24 different organizations using passive acoustic telemetry to document site fidelity, habitat preferences, seasonal migration patterns, and reproductive strategies of valuable sportfish, sharks, and marine turtles. FACT partners have found that by bundling resources, they can leverage a smaller investment to track highly mobile animals beyond a study area typically restrained in scale by funds and manpower. FACT is guided by several simple rules: use of the same type of equipment, locate receivers in areas that are beneficial to all researchers when feasible, maintain strong scientific ethics by recognizing that detection data on any receiver belongs to the tag owner, do not use other members detection data without permission and acknowledge FACT in publications. Partners have access to a network of 480 receivers deployed along a continuum of habitats from freshwater rivers to offshore reefs and covers 1100 km of coastline from the Dry Tortugas, Florida to South Carolina and extends to the Bahamas. Presently, 49 species, (25 covered by Fisheries Management Plans and five covered by the Endangered Species Act) have been tagged with 2736 tags in which 1767 tags are still active.

  19. Spatial variability in fish species assemblage and community structure in four subtropical lagoons of the Okavango Delta, Botswana

    Science.gov (United States)

    Mosepele, K.; Mosepele, B.; Bokhutlo, T.; Amutenya, K.

    The species assemblage and community structure of four lagoons was assessed through time series data collected between 2001 and 2005 in the Okavango Delta. The main aim of this study was to evaluate the importance of lagoons as fish habitats in the Delta. Therefore, this study assessed the importance of these habitats through determining fish species diversity, composition, relative abundance, and community structure between the lagoons. Forty six species belonging to 11 families and five orders were collected over the study period. Main results showed that Cichlidae was the most important family and had the highest species richness in the lagoons. Significant differences ( p lodges are constructed, which makes subsequently makes them vulnerable to pollution. Therefore, the integrity of lagoon habitats needs to be maintained so that their ecosystem functioning (i.e. fish repositories) is maintained.

  20. Linking pipefishes and seahorses to their habitat: implications for species conservation in the Venice lagoon

    Directory of Open Access Journals (Sweden)

    Luca Scapin

    2015-11-01

    Full Text Available Seagrass meadows of the Venice lagoon (Northern Adriatic Sea, Italy are spatially heterogeneous systems, with attributes such as degree of coverage and plant assemblages varying along multiple environmental gradients. They play a particularly relevant role in conservation of fish diversity, since they provide vital habitats for pipefish and seahorse species (family Syngnathidae. Aim of the study was to investigate the diversity of syngnathid assemblages in the Venice lagoon and link species distributions to habitat characteristics, in order to evaluate the importance of seagrass meadows of the lagoon for the conservation of these species. The analyses of this work are based on eight years of fish data collected between 2001 and 2014 in 186 shallow water sites across the entire lagoon. Water parameters, presence of macroalgae, seagrass presence and coverage, as well as meadows species composition, were considered as predictors in a modelling framework, to explain the distribution of each species. Overall, two species of seahorses and seven species of pipefishes including the Adriatic endemism Syngnathus taenionotus were found. Three species (S. abaster, S. typhle and Nerophis ophidion were the most abundant, together accounting for 98% of total individuals caught. Both seagrass presence and its coverage resulted significant predictors, with densities of S. abaster, S. typhle, N. ophidion and Hippocampus guttulatus being positively associated with higher percentages of seagrass cover. In addition, some evidences suggested a different functionality of different meadow types in supporting both S. typhle and N. ophidion. The study highlighted the role of Venice lagoon as biodiversity hotspot for syngnathids, since it supports nine out of the 10 species known in the Mediterranean (with only S. phlegon being absent. Results also suggested the importance of habitat management, which should aim at compensating for seagrass habitat loss and therefore

  1. Study on the sedimentation of the Olho D'Agua Lagoon, State of Pernambuco - Brazil

    International Nuclear Information System (INIS)

    Valentim, Eliane; Hazin, Clovis A.; Lima, Ricardo de A.; Amaral, Romilton S.; Godoy, Jose M.

    1999-01-01

    The Olho D'Agua Lagoon, placed in the municipal district of Jabotao of Guararapes, metropolitan area of Recife, is the main natural lagoon of the State of Pernambuco. For possessing a great potential paisagistic and environmental and for its extension, articulations between the City hall of Jaboatao of Guararapes and the Federal Government were accomplished in order to be built in I spill it of the lagoon a tourist park with the cooperation of several international organs. The urban and industrial development of this area happened the approximately 50 years ago, and ever since the Olho D'Agua Lagoon has if turned a deposit of domestic and industrial sink, because 95% of the spontaneous establishment are located in its margins and 15% are just assisted by sinks nets. So that a program of revitalization of this estuary is executed it is necessary to evaluate the ecological impact in this lagoon due to the activities. With base in this, it was determined the sedimentation rate and dating of its sediments in order to evaluate the pollution degree in the sets and to compare them with the profile of heavy metals and granulometer of the sediments. The obtained results show an expressive growth of the sedimentation rate, of 0,1 cm/year to 0,3 cm/year for 0,6 cm/year to 1,0 cm/year starting from the decade of 40. These results are in agreement with the text of heavy metals observed in each section of the lagoon and they agree with the industrial history of the area. (author)

  2. Bacterioplankton diversity and community composition in the Southern Lagoon of Venice.

    Science.gov (United States)

    Simonato, Francesca; Gómez-Pereira, Paola R; Fuchs, Bernhard M; Amann, Rudolf

    2010-04-01

    The Lagoon of Venice is a large water basin that exchanges water with the Northern Adriatic Sea through three large inlets. In this study, the 16S rRNA approach was used to investigate the bacterial diversity and community composition within the southern basin of the Lagoon of Venice and at one inlet in October 2007 and June 2008. Comparative sequence analysis of 645 mostly partial 16S rRNA gene sequences indicated high diversity and dominance of Alphaproteobacteria, Gammaproteobacteria and Bacteroidetes at the lagoon as well as at the inlet station, therefore pointing to significant mixing. Many of these sequences were close to the 16S rRNA of marine, often coastal, bacterioplankton, such as the Roseobacter clade, the family Vibrionaceae, and class Flavobacteria. Sequences of Actinobacteria were indicators of a freshwater input. The composition of the bacterioplankton was quantified by catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH) with a set of rRNA-targeted oligonucleotide probes. CARD-FISH counts corroborated the dominance of members of the phyla Alphaproteobacteria, Gammaproteobacteria and Bacteroidetes. When assessed by a probe set for the quantification of selected clades within Alphaproteobacteria and Gammaproteobacteria, bacterioplankton composition differed between October 2007 and June 2008, and also between the inlet and the lagoon. In particular, members of the readily culturable copiotrophic gammaproteobacterial genera Vibrio, Alteromonas and Pseudoalteromonas were enriched in the southern basin of the Lagoon of Venice. Interestingly, the alphaproteobacterial SAR11 clade and related clusters were also present in high abundances at the inlet and within the lagoon, which was indicative of inflow of water from the open sea.

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

    Science.gov (United States)

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

    2017-05-01

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

  4. Assessing the Impact of Animal Waste Lagoon Seepage on the Geochemistry of an Underlying Shallow Aquifer

    Energy Technology Data Exchange (ETDEWEB)

    McNab, W W; Singleton, M J; Moran, J E; Esser, B K

    2006-03-07

    Dairy facilities and similar confined animal operation settings pose a significant nitrate contamination threat via oxidation of animal wastes and subsequent transport to shallow groundwater. While nitrate contamination resulting from application of animal manure as fertilizer to fields is well recognized, the impact of manure lagoon leakage on groundwater quality is less well characterized. In this study, a dairy facility located in the southern San Joaquin Valley of California has been instrumented with monitoring wells as part of a two-year multidisciplinary study to evaluate nitrate loading and denitrification associated with facility operations. Among multiple types of data collected from the site, groundwater and surface water samples have been analyzed for major cations, anions, pH, oxidation-reduction potential, dissolved organic carbon, and selected dissolved gases (CO{sub 2}, CH{sub 4}, N{sub 2}, Ar, Ne). Modeling of putative geochemical processes occurring within the dairy site manure lagoons shows substantial off-gassing of CO{sub 2} and CH{sub 4} in response to mineralization of organic matter. The gas ebullition appears to strip dissolved gases, including Ar and Ne, from the lagoon water leaving concentrations that are undersaturated with respect to the atmosphere. The resulting fractionated dissolved gas signature serves as an effective tracer for the lagoon water in the underlying shallow groundwater and can be used to constrain inverse geochemical models that assess mixing fractions of lagoon water and local groundwater water. Together with ion exchange and mineral equilibria reactions, identification of lagoon seepage helps explain key attributes of the local groundwater chemistry, including input and cycling of nitrogen, across the site.

  5. Chasing boundaries and cascade effects in a coupled barrier-marsh-lagoon system

    Science.gov (United States)

    Lorenzo-Trueba, Jorge; Mariotti, Giulio

    2017-08-01

    The long-term dynamic evolution of an idealized barrier-marsh-lagoon system experiencing sea-level rise is studied by coupling two existing numerical models. The barrier model accounts for the interaction between shoreface dynamics and overwash flux, which allows the occurrence of barrier drowning. The marsh-lagoon model includes both a backbarrier marsh and an interior marsh, and accounts for the modification of the wave regime associated with changes in lagoon width and depth. Overwash, the key process that connects the barrier shoreface with the marsh-lagoon ecosystems, is formulated to account for the role of the backbarrier marsh. Model results show that a number of factors that are not typically associated with the dynamics of coastal barriers can enhance the rate of overwash-driven landward migration by increasing backbarrier accommodation space. For instance, lagoon deepening could be triggered by marsh edge retreat and consequent export of fine sediment via tidal dispersion, as well as by an expansion of inland marshes and consequent increase in accommodation space to be filled in with sediment. A deeper lagoon results in a larger fraction of sediment overwash being subaqueous, which coupled with a slow shoreface response sending sediment onshore can trigger barrier drowning. We therefore conclude that the supply of fine sediments to the back-barrier and the dynamics of both the interior and backbarrier marsh can be essential for maintaining the barrier system under elevated rates of sea-level rise. Our results highlight the importance of considering barriers and their associated backbarriers as part of an integrated system in which sediment is exchanged.

  6. 2014 Suwannee River Water Management District Lidar: Cooks Hammock (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the Suwannee River G14PD00206 0.7 Meter LiDAR Survey in central Florida and encompasses 571 square...

  7. 2013 Suwannee River Water Management District (SRWMD) Lidar: Ichetucknee (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the Suwannee River G12PD00242 1.0 Meter LiDAR Survey area 2 in north-central Florida and encompasses...

  8. Suwannee River Water Management District Lidar: Falmouth (FL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Light Detection and Ranging (LiDAR) dataset is a survey of the Suwannee River G12PD00242 1.0 Meter LiDAR Survey area 5 in north-central Florida and encompasses...

  9. Methodology for the selection of the regime of flow in lagoons of stabilization

    International Nuclear Information System (INIS)

    Cruz T, Luis Eduardo; Alayon Torres, Walter E; Monsegny S, Carlos Emilio

    2000-01-01

    To model biological processes, information is needed on the stoichiometry and kinetics of the reactions and about the hydraulic regime of the system. The stoichiometry of a reaction refers to the quantity of consumed reactants (such as substrates) and to the quantity of formed products (such as microorganisms). The hydraulic regime makes reference to the configuration of the flow inside of and outside of the process and to the mixture and distribution of the solids of the fluid inside the reactor. The present article it is centered in studying the different mixture regimens and its kinetic models of degradation of organic matter applied to the case specify of the lagoon of stabilization of residual waters of the Municipality of Tocancipa; also it the methodology discusses to determine the type of flow that is presented in a stabilization lagoon. The kinetic models of degradation of organic matter in stabilization lagoons are classified according with the presence or absence of oxygen in the lagoon and with the mixture regime that it is presented in this. The regimens of flow that are presented in the stabilization lagoons are those of complete mixture and the piston flow, one completely opposed to the other one. Between these two is the denominated regime of dispersed or arbitrary flow. The determination of the mixture regime is of great importance, since with this it is possible to have an idea of the behavior of the rates of removal of the nutrients that arrive to the system, of the consumption of oxygen and the kinetic pattern of removal of organic matter among others. The regime of mixture complete ideal this characterized because the mass of water that enters to the system is dispersed instantly, making that the characteristics of the water are the same ones in any point, that is to say that the reaction rates are constant in the reactor and the demand of oxygen it is identical in any sampling point, likewise it happens with the removal rate; this has big

  10. Dioxins in the Venice lagoon: Present situation, projects and recovering hypotheses.

    Science.gov (United States)

    Raccanelli, S; Bonamin, V

    2000-01-01

    Venice is famous around the world for its uniqueness and architectural splendours, arts and the history of the "Serenissima Repubblica", as it was known in the past, but few are aware that Venice economy is strongly dependent on the industrial activities based mainly on the adjacent Porto Marghera area. For many years, the lagoon that physically separates the city from the dry land has avoided association between the concern connected with the pollution derived from these industrial activities and the public perception of Venice. Since 1995, dioxins have appeared as a lagoon contaminant, and their presence, at such a level requiring immediate "in depth" studies and interventions, has been fully realized for decades.

  11. Temporal stability of otolith elemental fingerprints discriminates among lagoon nursery habitats

    Science.gov (United States)

    Tournois, Jennifer; Ferraton, Franck; Velez, Laure; McKenzie, David J.; Aliaume, Catherine; Mercier, Lény; Darnaude, Audrey M.

    2013-10-01

    The chemical composition of fish otoliths reflects that of the water masses that they inhabit. Otolith elemental compositions can, therefore, be used as natural tags to discriminate among habitats. However, for retrospective habitat identification to be valid and reliable for any adult, irrespective of its age, significant differences in environmental conditions, and therefore otolith signatures, must be temporally stable within each habitat, otherwise connectivity studies have to be carried out by matching year-classes to the corresponding annual fingerprints. This study investigated how various different combinations of chemical elements in otoliths could distinguish, over three separate years, between four coastal lagoon habitats used annually as nurseries by gilthead sea bream (Sparus aurata L.) in the Gulf of Lions (NW Mediterranean). A series of nine elements were measured in otoliths of 301 S. aurata juveniles collected in the four lagoons in 2008, 2010 and 2011. Percentages of correct re-assignment of juveniles to their lagoon of origin were calculated with the Random Forest classification method, considering every possible combination of elements. This revealed both spatial and temporal variations in accuracy of habitat identification, with correct re-assignment to each lagoon ranging from 44 to 99% depending on the year and the lagoon. There were also annual differences in the combination of elements that provided the best discrimination among the lagoons. Despite this, when the data from the three years were pooled, a combination of eight elements (B, Ba, Cu, Li, Mg, Rb, Sr and Y) provided greater than 70% correct re-assignment to each single lagoon, with a multi-annual global accuracy of 79%. When considering the years separately, discrimination accuracy with these elemental fingerprints was above 90% for 2008 and 2010. It decreased to 61% in 2011, when unusually heavy rainfall occurred, which presumably reduced chemical differences among several of the

  12. THE APPLICATION OF A BPL INDEX IN THE POLISH PART OF THE VISTULA LAGOON

    Directory of Open Access Journals (Sweden)

    Monika Agnieszka Michałek

    2015-01-01

    Full Text Available This paper presents a biopollution assessment results with respect to macrozoobenthic non-indigenous species in the Polish part of the Vistula Lagoon. A biopollution level index (BPL was applied and evaluated based on the studies on macrozoobenthos conducted in 2010 and 2012 within the frame of several individual projects. Overall 15 macrozoobenthic species were identified, 5 of which were aquatic alien species: Marenzelleria neglecta, Rhitropanopeus harrissi, Potamopyrgus antipodarum, Dreissena polymorpha and Rangia cuneata. According to the applied criteria the Vistula Lagoon was moderately influenced by invasive species.

  13. Seasonal succession of cyanoprokaryotes in a hypereutrophic oligo-mesohaline lagoon from the South of France

    Science.gov (United States)

    Chomérat, Nicolas; Garnier, Robert; Bertrand, Céline; Cazaubon, Arlette

    2007-05-01

    The Bolmon lagoon (South of France) is an oligo-mesohaline coastal lagoon that has undergone intense eutrophication in the past decades, resulting from a strong concentration of human activities in its drainage basin. Consequently, it exhibits some characteristics typical of an advanced trophic state; namely, the disappearance of submerged vegetation, the permanently intense phytoplankton growth and the recurrence of cyanoprokaryote blooms. As cyanoprokaryote dominance in south-temperate saline lagoons is little reported, we carried out this study in order to understand the seasonal variations in the phytoplankton composition and biomass, and to analyse the influence of environmental parameters such as salinity, nutrients and climate on the seasonal succession of species. In this lagoon, the phytoplankton was permanently dominated by cyanoprokaryotes, probably because of high availability of nutrients, low light penetration in the water column and frequent turbulent mixing induced by wind. The two most abundant species Planktothrix agardhii (in winter-spring) and Pseudanabaena limnetica (in summer) have low light requirements and are well adapted to a high mixing frequency, which defines the S1 functional group in Reynolds' typology for phytoplankton. Although widely studied in north-temperate lakes, blooms of these typically freshwater species are almost unreported in the Mediterranean area, especially in brackish ecosystems that are not their normal habitat. In the Bolmon lagoon, all their requirements for nutrients, light and mixing are satisfied and they seem to cope with a moderate presence of salt but P. agardhii was less competitive than P. limnetica at highest salinities, the latter being probably more halophytic. Contrary to the observations in lakes located at higher latitudes, the Mediterranean climate seems to induce a typical seasonal pattern of succession characterised by the dominance of P. agardhii (winter) - Chroococcales (spring

  14. The Caloosahatchee River Estuary: a monitoring partnership between Federal, State, and local governments, 2007-13

    Science.gov (United States)

    Patino, Eduardo

    2014-01-01

    The tidal Caloosahatchee River and downstream estuaries have substantial environmental, recreational, and economic value for southwest Florida residents and visitors. Modifications to the Caloosahatchee River watershed have altered the predevelopment hydrology, thereby threatening the environmental health of estuaries in the area. Hydrologic monitoring of the freshwater contributions from tributaries to the tidal Caloosahatchee River and its estuaries is necessary to adequately describe the total freshwater inflow and constituent loads to the delicate estuarine system.

  15. NASA Hydrogen Research at Florida Universities

    International Nuclear Information System (INIS)

    David L Block; Ali T-Raissi

    2006-01-01

    This paper presents a summary of the activities and results from 36 hydrogen research projects being conducted over a four-year period by Florida universities for the U. S. National Aeronautics and Space Administration (NASA). The program entitled 'NASA Hydrogen Research at Florida Universities' is managed by the Florida Solar Energy Center (FSEC). FSEC has 22 years of experience in conducting research in areas related to hydrogen technologies and fuel cells. The R and D activities under this program cover technology areas related to production, cryogenics, sensors, storage, separation processes, fuel cells, resource assessments and education. (authors)

  16. Distribution and migration of pesticide residues in mosquito control impoundments St. Lucie County, Florida, USA

    Science.gov (United States)

    Parkinson, R. W.; Wang, T. C.; White, J. R.; David, J. R.; Hoffman, M. E.

    1993-09-01

    This project was designed to: (1) document the distribution and migration of organochlorine pesticide residues within marsh substrates of 18 St. Lucie County mosquito control impoundments located along the Indian River Lagoon estuary, and (2) evaluate the impact of water management techniques on residue mobility. Our results indicate that detectible concentrations of organochlorine compounds, applied between the late 1940s and early 1950s, are present in 16 of the 18 St. Lucie County mosquito control impoundments. These compounds are primarily restricted to the surficial, organic-rich wetland sediment, which, based upon geotechnical analysis, was exposed to the atmosphere at a time when the impoundments were subjected to pesticide treatment. Contaminated sediments are present below the surficial, organic-rich layer, suggesting that some vertical migration of pesticides has occurred. It is unlikely that leaching associated with the downward percolation of impounded water was responsible for this migration as pesticide residues were never detected within the in situ pore waters. An alternative explanation is that biological processes (e.g., rooting, burrowing) facilitated the downward flux of organochlorine compounds into sediment horizons not subjected to direct treatment. Eighty-eight surface water samples obtained from two impoundments subjected to contrasting water management techniques were analyzed for pesticide content. None of the surficial water samples collected in association with these impoundments contained detectible concentrations of organochlorine compounds. These samples were unfiltered and contained as much as 25 mg/1 of particulate organic matter. This suggests that the currently preferred management technique (RIM), which is designed to maintain water quality, limit mosquito production, and provide for ecological continuity, does not hydraulically mobilize pesticide residues into the Indian River Lagoon estuary.

  17. Millennial, centennial and decadal sea- level change in Florida, USA

    Science.gov (United States)

    Kemp, A.; Hawkes, A. D.; Donnelly, J. P.; Horton, B. P.

    2012-12-01

    Reconstructions of relative sea-level changes on millennial timescales provide data against which to test and calibrate Earth-Ice models. On the U.S. mid-Atlantic coast they constrain the geometry of the Laurentide Ice Sheet's collapsing forebulge. Sea -level data from southeastern Atlantic coast additionally constrain ice-equivalent meltwater input. Here we produce the first Holocene sea-level curve for Florida and Georgia from the St. Mary's River using agglutinated foraminifera preserved in radiocarbon-dated brackish and salt-marsh sediment. The use of foraminfera as sea-level indicators was underpinned by local and regional datasets describing the modern distribution of assemblages that are analogues for those preserved in buried sediment. This approach produced 25 index points that record 5.2 m of relative sea level rise over the last 8000 years with no evidence of a mid Holocene high stand. These reconstructions indicate that existing GIA models do not replicate proxy reconstructions and that northern Florida is subsiding in response to ongoing forebulge collapse at an estimated rate of approximately 0.3 mm/yr. Over multi decadal time scales, detailed sea level reconstructions provide an appropriate geological context for modern rates of sea-level rise. Reconstructions spanning the last 2000 years of known climate variability are important for developing models with predictive capacity that link climate and sea level changes. A reconstruction of sea-level changes since 2000 years BP was developed using a core of brackish marsh sediment from the Nassau River in Florida. Foraminifera estimated the elevation of former sea level with an uncertainty of ± 10 cm. Consistent downcore assemblages indicate that the marsh maintained its tidal elevation for 2000 years. An age depth model was developed for the core results from radiocarbon dating, 210Pb and 137Cs. The resulting relative sea level record was adjusted for the contribution made by glacio

  18. Use of an estuarine environment (Barra do Saí lagoon, Brazil as nursery by fish Utilização de um ambiente estuarino (Santa Catarina, Brasil como berçário de peixes

    Directory of Open Access Journals (Sweden)

    Ana L. Vendel

    2006-12-01

    Full Text Available Studies were carried out at the Barra do Saí lagoon, on the northern coast of Santa Catarina State, Brazil, to evaluate the function played by this estuary in the life cycle of fish found at the coastal zone. Samplings were performed using beach seine net from December 2000 to November 2001. The continental influence is strong, as showed by the occurrence of freshwater fishes, although most of the 43 species recorded are marine ones. It was verified that around summer, when the temperature of the water is high, the values of salinity decrease and those of turbidity increase. At this time there is also an increase in the abundance of juvenile fish in the lagoon. Because of its average depth of less than 0.7 m, the lagoon is inhabited primarily by juveniles, which may enter either by active movement or passive displacement, originating from the sea or the river to which the lagoon is connected. The lagoon is not used for sheltering spawning individuals. It is showed that a shallow, small estuary with a blind bottom can conceal an importance for the coastal ichthyofauna that is greater than it could be expected from the occurrence - in this case, modest - of large individuals.A laguna de Barra do Saí, litoral norte de Santa Catarina, foi estudada para avaliar o papel desse estuário no ciclo de vida de peixes da zona costeira. Arrastos de praia foram realizados, e dados abióticos e de biometria foram obtidos, de dezembro de 2000 a novembro de 2001. No verão, quando a temperatura da água se eleva, diminuem os valores de salinidade e aumentam os de turbidez. A influência fluvial é corroborada pela ocorrência de espécies dulceaqüícolas, embora a maioria das 43 espécies registradas na laguna seja marinha. É também nesta época que aumenta a abundância de peixes jovens. O sistema não se notabiliza por acolher indivíduos em desova: face à baixa profundidade, ele é habitado essencialmente pelos jovens, que possivelmente ingressam em

  19. Spatial patterns of fish communities along two estuarine gradients in southern Florida

    Science.gov (United States)

    Green, D.P.J.; Trexler, J.C.; Lorenz, J.J.; McIvor, C.C.; Philippi, T.

    2006-01-01

    In tropical and subtropical estuaries, gradients of primary productivity and salinity are generally invoked to explain patterns in community structure and standing crops of fishes. We documented spatial and temporal patterns in fish community structure and standing crops along salinity and nutrient gradients in two subtropical drainages of Everglades National Park, USA. The Shark River drains into the Gulf of Mexico and experiences diurnal tides carrying relatively nutrient enriched waters, while Taylor River is more hydrologically isolated by the oligohaline Florida Bay and experiences no discernable lunar tides. We hypothesized that the more nutrient enriched system would support higher standing crops of fishes in its mangrove zone. We collected 50 species of fish from January 2000 to April 2004 at six sampling sites spanning fresh to brackish salinities in both the Shark and Taylor River drainages. Contrary to expectations, we observed lower standing crops and density of fishes in the more nutrient rich tidal mangrove forest of the Shark River than in the less nutrient rich mangrove habitats bordering the Taylor River. Tidal mangrove habitats in the Shark River were dominated by salt-tolerant fish and displayed lower species richness than mangrove communities in the Taylor River, which included more freshwater taxa and yielded relatively higher richness. These differences were maintained even after controlling for salinity at the time of sampling. Small-scale topographic relief differs between these two systems, possibly created by tidal action in the Shark River. We propose that this difference in topography limits movement of fishes from upstream marshes into the fringing mangrove forest in the Shark River system, but not the Taylor River system. Understanding the influence of habitat structure, including connectivity, on aquatic communities is important to anticipate effects of construction and operational alternatives associated with restoration of the

  20. Tracing the sources of fine sediment in a nickel mining catchment using fallout and geogenic radionuclides (Thio River, New Caledonia)

    Science.gov (United States)

    Evrard, Olivier; Navratil, Oldrich; Lefèvre, Irène; Laceby, J. Patrick; Allenbach, Michel

    2016-04-01

    Soil erosion and subsequent sediment transfer in rivers are exacerbated in tropical regions exposed to heavy rainfall. In New Caledonia, an island located in the southwestern part of the Southern Pacific Ocean, a significant fraction of this sediment is likely originating from tributaries draining nickel mining sites that are known to increase the terrigenous inputs to the rivers and, potentially to UNESCO World Heritage listed coastal lagoons. However, downstream contributions from these tributaries remain to be quantified. A pilot sediment tracing study has therefore been conducted in the 400-km² Thio River catchment. Fallout and geogenic radionuclides have been measured in sediment deposits collected in potential sources, i.e. (i) tributaries draining mines, (ii) tributaries draining 'natural' areas affected by landslides, and (iii) the main stem of the Thio River. Thorium-228 and Caesium-137 provide the best discrimination between sediment originating from the two tributaries. A distribution modelling approach was used to quantify the relative sediment contributions from these tributaries to the Thio River main stem. Results demonstrate that tributaries draining mining sites supply the majority of sediment (67-84%) to the main river. In the future, the validity of these results obtained on sediment deposits collected in April and May 2015 should be verified over a longer time period by applying a similar approach to sediment cores collected in the Thio river deltaic plain. Once validated, this method will be applicable to other catchments draining mines in New Caledonia to design appropriate measures to limit sediment supply to the lagoon.