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Sample records for hudson river estuary

  1. Transport of fallout and reactor radionuclides in the drainage basin of the Hudson River estuary

    International Nuclear Information System (INIS)

    Simpson, H.J.; Linsalata, P.; Olsen, C.R.

    1982-01-01

    The transport and fate of Strontium 90, Cesium 137 and Plutonium 239, 240 in the Hudson River Estuary is discussed. Rates of radionuclide deposition and accumulation over time and space are calculated for the Hudson River watershed, estuary, and continental shelf offshore. 37 references, 7 figures, 15 tables

  2. Desorption of Ba and 226Ra from river-borne sediments in the Hudson estuary

    International Nuclear Information System (INIS)

    Li, Y.-H.

    1979-01-01

    The pronounced desorption of Ba and 226 Ra from river-borne sediments in the Hudson estuary can be explained quantitatively by the drastic decrease in the distribution coefficients of both elements from a fresh to a salty water medium. The desorption in estuaries can augment, at least, the total global river fluxes of dissolved Ba and 226 Ra by one and nine times, respectively. The desorption flux of 226 Ra from estuaries accounts for 17-43% of the total 226 Ra flux from coastal sediments. Two mass balance models depicting mixing and adsorption-desorption processes in estuaries are discussed. (Auth.)

  3. Benthic bacterial biomass and production in the Hudson River estuary

    International Nuclear Information System (INIS)

    Austin, H.K.; Findlay, S.E.G.

    1989-01-01

    Bacterial biomass, production, and turnover were determined for two freshwater march sites and a site in the main river channel along the tidally influenced Hudson River. The incorporation of [methyl- 3 H]thymidine into DNA was used to estimate the growth rate of surface and anaerobic bacteria. Bacterial production at marsh sites was similar to, and in some cases considerably higher than, production estimates reported for other aquatic wetland and marine sediment habitats. Production averaged 1.8-2.8 mg C·m -2 · hour -1 in marsh sediments. Anaerobic bacteria in marsh sediment incorporated significant amounts of [methyl- 3 H]thymidine into DNA. Despite differences in dominant vegatation and tidal regime, bacterial biomass was similar (1 x 10 3 ± 0.08 mg C·m -2 ) in Trapa, Typha, and Nuphar aquatic macrophyte communities. Bacterial abundance and productivity were lower in sandy sediments associated with Scirpus communities along the Hudson River (0.2 x 10 3 ± 0.05 mg C·m -2 and 0.3 ± 0.23 mg C · m -2 · hour -1 , respectively)

  4. Salt Marsh Formation in the Lower Hudson River Estuary

    Science.gov (United States)

    Merley, Michael; Peteet, Dorothy; Hansen, James E. (Technical Monitor)

    2001-01-01

    Salt marshes are constant depositional environments and as a result contain accurate indicators of past relative sea level rise and salinity. The Hudson River marshes are at least twice as deep when compared to coastal marshes on either side of the mouth of the Hudson. The reason for this difference in sedimentation is unclear. This study uses macrofossil data as well as sediment stratigraphy in order to understand the formation and evolution of these marshes. The composition of seeds, roots, shoots and foraminifera, are used to indicate past sea levels. The four sites involved in this study are, from south to north, the Arthur Kill Marsh in Staten Island (40 36 N, 74 77W), Piermont marsh (N 4100; 73 55W) Croton Point (41 14 N; 73 50W) and Iona Island (41 18N, 73 58W). These are all tidally influenced but with increasing distances from the New York Bight, which gives a good spectrum of tidal influence. AMS-C14 dates on basal macrofossils will document the time of each marsh formation. Basal material from Arthur Kill (8 m) includes freshwater seeds such as Viola, Potomageton and Alnus along with Salix buds. Basal material from Croton Point (10 m) includes fibrous woody material, foraminifera and Zanichellia seeds and other brackish vegetational components. The basal material from Piermont (13.77 m) is lacking any identifiable macrofossils between 150 and 500 microns. The basal material from Iona Island (10 m) has vegetation such as Scirpus and Cyperus seeds, probably implying a brackish environment. The freshwater origin of the Arthur Kill marsh in Staten Island is significant because it predates either sea level rise or the western channel incision. Additional implications for this study include evidence for changes in river channel geomorphology. Reasons for the relatively deeper river marshes include possible basal clay compaction, high production due to river and marine nutrients as well as tectonic activity. This study provides the groundwork for more high

  5. The partitioning of Triclosan between aqueous and particulate bound phases in the Hudson River Estuary

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Brittan [University of Massachusetts, Department of Environment, Earth and Ocean Sciences, 100 Morrissey Blvd., Boston, MA 02125 (United States); Chen, Robert F. [University of Massachusetts, Department of Environment, Earth and Ocean Sciences, 100 Morrissey Blvd., Boston, MA 02125 (United States); Cantwell, Mark [NHEERL, Atlantic Ecology Division, US Environmental Protection Agency, 27 Tarzwell Drive, Narragansett, RI 02882 (United States); Gontz, Allen; Jun, Zhu; Olsen, Curtis R. [University of Massachusetts, Department of Environment, Earth and Ocean Sciences, 100 Morrissey Blvd., Boston, MA 02125 (United States)

    2009-07-01

    The distribution of Triclosan within the Hudson River Estuary can be explained by a balance among the overall effluent inputs from municipal sewage treatment facilities, dilution of Triclosan concentrations in the water column with freshwater and seawater inputs, removal of Triclosan from the water column by adsorption to particles, and loss to photodegradation. This study shows that an average water column concentration of 3 {+-} 2 ng/l (in the lower Hudson River Estuary) is consistent with an estimate for dilution of average wastewater concentrations with seawater and calculated rates of adsorption of Triclosan to particles. An average Triclosan sediment concentration of 26 {+-} 11 ng/g would be in equilibrium with the overlying water column if Triclosan has a particle-to-water partitioning coefficient of k{sub d} {approx} 10{sup 4}, consistent with laboratory estimates.

  6. The partitioning of Triclosan between aqueous and particulate bound phases in the Hudson River Estuary

    International Nuclear Information System (INIS)

    Wilson, Brittan; Chen, Robert F.; Cantwell, Mark; Gontz, Allen; Zhu Jun; Olsen, Curtis R.

    2009-01-01

    The distribution of Triclosan within the Hudson River Estuary can be explained by a balance among the overall effluent inputs from municipal sewage treatment facilities, dilution of Triclosan concentrations in the water column with freshwater and seawater inputs, removal of Triclosan from the water column by adsorption to particles, and loss to photodegradation. This study shows that an average water column concentration of 3 ± 2 ng/l (in the lower Hudson River Estuary) is consistent with an estimate for dilution of average wastewater concentrations with seawater and calculated rates of adsorption of Triclosan to particles. An average Triclosan sediment concentration of 26 ± 11 ng/g would be in equilibrium with the overlying water column if Triclosan has a particle-to-water partitioning coefficient of k d ∼ 10 4 , consistent with laboratory estimates.

  7. Seasonal air-water exchange fluxes of polychlorinated biphenyls in the Hudson River Estuary

    International Nuclear Information System (INIS)

    Yan Shu; Rodenburg, Lisa A.; Dachs, Jordi; Eisenreich, Steven J.

    2008-01-01

    Polychlorinated biphenyls (PCBs) were measured in the air and water over the Hudson River Estuary during six intensive field campaigns from December 1999 to April 2001. Over-water gas-phase ΣPCB concentrations averaged 1100 pg/m 3 and varied with temperature. Dissolved-phase ΣPCB concentrations averaged 1100 pg/L and displayed no seasonal trend. Uncertainty analysis of the results suggests that PCBs with 5 or fewer chlorines exhibited net volatilization. The direction of net air/water exchange could not be determined for PCBs with 6 or more chlorines. Instantaneous net fluxes of ΣPCBs ranged from +0.2 to +630 ng m -2 d -1 . Annual fluxes of ΣPCBs were predicted from modeled gas-phase concentrations, measured dissolved-phase concentrations, daily surface water temperatures and wind speeds. The net volatilization flux was +62 μg m -2 yr -1 , corresponding to an annual loss of +28 kg/yr of ΣPCBs from the Hudson River Estuary for the year of 2000. - Investigation of the air-water exchange of PCBs in the Hudson River Estuary suggests that PCBs with 5 or fewer chlorines undergo net volatilization

  8. Spatial patterns of pharmaceuticals and wastewater tracers in the Hudson River Estuary.

    Science.gov (United States)

    Cantwell, Mark G; Katz, David R; Sullivan, Julia C; Shapley, Daniel; Lipscomb, John; Epstein, Jennifer; Juhl, Andrew R; Knudson, Carol; O'Mullan, Gregory D

    2018-06-15

    The widespread use of pharmaceuticals by human populations results in their sustained discharge to surface waters via wastewater treatment plants (WWTPs). In this study, 16 highly prescribed pharmaceuticals were quantified along a 250 km transect of the Hudson River Estuary and New York Harbor to describe their sources and spatial patterns. Sampling was conducted over two dry weather periods in May and July 2016, at 72 sites which included mid-channel and nearshore sites, as well as locations influenced by tributaries and WWTP outfalls. The detection frequency of the study pharmaceuticals was almost identical between the May and July sampling periods at 55% and 52%, respectively. Six pharmaceuticals were measurable at 92% or more of the sites during both sampling periods, illustrating their ubiquitous presence throughout the study area. Individual pharmaceutical concentrations were highly variable spatially, ranging from non-detect to 3810 ng/L during the study. Major factors controlling concentrations were proximity and magnitude of WWTP discharges, inputs from tributaries and tidal mixing. Two compounds, sucralose and caffeine, were evaluated as tracers to identify wastewater sources and assess pharmaceutical behavior. Sucralose was useful in identifying wastewater inputs to the river and concentrations showed excellent correlations with numerous pharmaceuticals in the study. Caffeine-sucralose ratios showed potential in identifying discharges of untreated wastewater occurring during a combined sewage overflow event. Many of the study pharmaceuticals were present throughout the Hudson River Estuary as a consequence of sustained wastewater discharge. Whereas some concentrations were above published effects levels, a more complete risk assessment is needed to understand the potential for ecological impacts due to pharmaceuticals in the Hudson River Estuary. Published by Elsevier Ltd.

  9. 2010 Hudson River Shallow Water Sediment Cores

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Hudson River Shallow Water Mapping project characterizes the bottom of the Hudson River Estuary in shallow water (<3 m). The characterization includes...

  10. 239 240Pu and 238Pu in sediments of the Hudson River estuary

    International Nuclear Information System (INIS)

    Linsalata, P.; Wrenn, M.E.; Cohen, N.; Singh, N.P.

    1980-01-01

    Plutonium-239,240 and plutonium-238 were determined in 59 Hudson River sediment dredge samples collected during 1973-77 in the vicinity of the Indian Point Nuclear Power Station. Acid leaching followed by solvent extraction, electrodeposition, and alpha-spectrometry were used to extract, purify, and quantitate plutonium isotopes present in these samples. Annual median plutonium-238/plutonium-239,240 isotopic activity ratios in surficial sediments were 0.032 (1973-74), 0.035 (1975), 0.042 (1976), and 0.040 (1977). The source of these nuclides in the estuary was identified by analysis of the sample isotopic activity ratios. On the basis of the sampling regimen and the methods used, it is concluded that no input, other than that of fallout, has contributed significantly to the plutonium burden in Hudson sediments

  11. Transport of fallout and reactor radionuclides in the drainage basin of the Hudson River estuary

    International Nuclear Information System (INIS)

    Simpson, H.J.; Linsalata, P.; Olsen, C.R.; Cohen, N.; Trier, R.M.

    1987-01-01

    Fallout plutonium and radiocesium derived from both weapons testing and local reactor releases are found in the water column and sediments of the Hudson River in readily measurable amounts. The history of fallout delivery and dissolved phase runoff from the drainage basin of 80 Sr, 137 Cs, and /sup 239,240/Pu have been extensively documented since the mid-1950s. Sediment and water column concentrations of 134 Cs, 137 Cs, and /sup 239,240/Pu in the Hudson have also been documented since the mid-1960's and are summarized. Since the peak fallout years, substantial portions of the fallout radionuclides in the drainage basin have become unavailable to normal weathering processes as reflected by a measured decrease in the fallout nuclide transport to the waters of the tidal Hudson. Budget calculations indicate that plutonium may be transported into the estuary from the coastal ocean, and that desorption of radiocesium from particles has allowed a substantial fraction of radiocesium to be exported from the Hudson to marine waters. 29 references, 6 figures, 8 tables

  12. Impact of entrainment and impingement on fish populations in the Hudson River estuary. Volume I. Entrainment-impact estimates for six fish populations inhabiting the Hudson River estuary

    International Nuclear Information System (INIS)

    Boreman, J.; Barnthouse, L.W.; Vaughn, D.S.; Goodyear, C.P.; Christensen, S.W.; Kumar, K.D.; Kirk, B.L.; Van Winkle, W.

    1982-01-01

    This volume is concerned with the estimation of the direct (or annual) entrainment impact of power plants on populations of striped bass, white perch, Alosa spp. (blueback herring and alewife), American shad, Atlantic tomcod, and bay anchovy in the Hudson River estuary. Entrainment impact results from the killing of fish eggs, larvae, and young juveniles that are contained in the cooling water cycled through a power plant. An Empirical Transport Model (ETM) is presented as the means of estimating a conditional entrainment mortality rate (defined as the fraction of a year class which would be killed due to entrainment in the absence of any other source of mortality). Most of this volume is concerned with the estimation of several parameters required by the ETM: physical input parameters (e.g., power-plant withdrawal flow rates); the longitudinal distribution of ichthyoplankton in time and space; the duration of susceptibility of the vulnerable organisms; the W-factors, which express the ratios of densities of organisms in power plant intakes to densities of organisms in the river; and the entrainment mortality factors (f-factors), which express the probability that an organism will be killed if it is entrained. Once these values are obtained, the ETM is used to estimate entrainment impact for both historical and projected conditions

  13. Three-dimensional simulation of flow, salinity, sediment, and radionuclide movements in the Hudson River estuary

    International Nuclear Information System (INIS)

    Onishi, Y.; Trent, D.S.

    1985-04-01

    The three-dimensional, finite difference model, FLESCOT simulates time-varying movements of flow, turbulent kinetic energy, salinity, water temperature, sediment, and contaminants in estuarine, coastal, and ocean waters. The model was applied to a 106-km (66-mi) reach of the Hudson River estuary in New York between Chelsea and the mouth of the river. It predicted the time-varying, three-dimensional distributions of tidal flow, salinity, three separate groups of sediments (i.e., sand, silt, and clay), and a radionuclide ( 137 Cs) in both dissolved and particulate (those sorbed by sediments) forms for over 40 days. The model also calculated riverbed elevation changes caused by sediment deposition and bed erosion, bed sediment size distribution and armoring, and distributions of the particulate 137 Cs sorbed by sand, silt, and clay in the bed

  14. Diatoms as Proxies for Abrupt Events in the Hudson River Estuary

    Science.gov (United States)

    Skorski, W.; Abbott, D. H.; Recasens, C.; Breger, D. L.

    2014-12-01

    The Hudson River estuary has been subject to many abrupt events throughout its history including hurricanes, droughts and pluvials. Hurricanes in particular are rare, discrete events that if fingerprinted can be used to develop better age models for Hudson River sediments. Proxies use observed physical characteristics or biological assemblages (e.g. diatom and foraminiferal assemblages) as tools to reconstruct past conditions prior to the modern instrumental record. Using a sediment core taken from the Hudson River (CDO2-29A), in New York City, drought and pluvial layers were selected based on Cs-137 dating while hurricane layers were determined from occurrences of tropical to subtropical foraminifera. Contrary to previous studies (Weaver, 1970, Weiss et al, 1978), more than sixty different diatom species have been identified using a scanning electron microscope (SEM). Cosmopolitan, hurricane and drought assemblages have begun to be identified after observing multiple layers (Table 1). Tropical foraminifera dominated by Globigerinoides ruber pink were also found in a hurricane layer that we infer was deposited during Hurricane Belle in 1976. More diatom abundance analyses and cataloged SEM pictures will provide further insight into these proxies. Table 1 Diatom Genera and Species Environment Clarification Cyclotella caspia Planktonic, marine-brackish Cosmopolitan Karayevia clevei Freshwater Cosmopolitan Melosira sp Planktonic, marine Cosmopolitan Thalassiosira sp Marine, brackish Cosmopolitan Staurosirella leptostauron Benthic, freshwater Cosmopolitan Actinoptychus senarius Planktonic or benthic, freshwater to brackish Hurricane and pluvial layers Amphora aff. sp Benthic, marine or freshwater Hurricane layers only Nitzschia sp Benthic, marine or freshwater Hurricane layers only Gomphonema sp Freshwater Hurricane layers only Surirella sp Marine-brackish Drought layer only Triceratium sp Marine Drought layer only Other Genera and species Environment Clarification

  15. Hudson River Sub-Bottom Profile Points

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hudson River Estuary Shallow Water Surveys. Subbottom Profile Points. Subbottom data was collected November 5 to December 15, 2009, in the estuary north from...

  16. Estimates of entrainment mortality for striped bass and other fish species inhabiting the Hudson River estuary

    International Nuclear Information System (INIS)

    Boreman, J.; Goodyear, C.P.

    1988-01-01

    An empirically derived age-, time-, and space-variant equation was used to estimate entrainment mortality at power plants for seven fish species inhabiting the Hudson River estuary. Entrainment mortality is expressed as a conditional rate, which is the fractional reduction in year-class strength due to entrainment if other sources of mortality are density-independent. Estimates of the conditional entrainment mortality, based on historical and projected once-through cooling operation of five power plants, were 11-22% for striped bass, 11-17% for white perch, 5-7% for Atlantic tomcod, 14-21% for American shad, 4-11% for river herring (alewife and blueback herring combined), and 35-79% for bay anchovy. Closed-cycle cooling (natural-draft cooling towers) at three of the power plants (Indian Point, Bowline Point, and Roseton) would reduce entrainment mortality of striped bass by 50-80%, of white perch by 75-80%, of Atlantic tocod by 65-70%, of American shad by 80%, of river herring by 30-90%, and of bay anchovy by 45-80%. The life stages most vulnerable to entrainment mortality were post-yolk-sac larva and entrainable size juvenile. 18 refs., 7 tabs

  17. Widespread Micropollutant Monitoring in the Hudson River Estuary Reveals Spatiotemporal Micropollutant Clusters and Their Sources.

    Science.gov (United States)

    Carpenter, Corey M G; Helbling, Damian E

    2018-06-05

    The objective of this study was to identify sources of micropollutants in the Hudson River Estuary (HRE). We collected 127 grab samples at 17 sites along the HRE over 2 years and screened for up to 200 micropollutants. We quantified 168 of the micropollutants in at least one of the samples. Atrazine, gabapentin, metolachlor, and sucralose were measured in every sample. We used data-driven unsupervised methods to cluster the micropollutants on the basis of their spatiotemporal occurrence and normalized-concentration patterns. Three major clusters of micropollutants were identified: ubiquitous and mixed-use (core micropollutants), sourced from sewage treatment plant outfalls (STP micropollutants), and derived from diffuse upstream sources (diffuse micropollutants). Each of these clusters was further refined into subclusters that were linked to specific sources on the basis of relationships identified through geospatial analysis of watershed features. Evaluation of cumulative loadings of each subcluster revealed that the Mohawk River and Rondout Creek are major contributors of most core micropollutants and STP micropollutants and the upper HRE is a major contributor of diffuse micropollutants. These data provide the first comprehensive evaluation of micropollutants in the HRE and define distinct spatiotemporal micropollutant clusters that are linked to sources and conserved across surface water systems around the world.

  18. Plutonium, radiocesium and radiocobalt in sediments of the Hudson River estuary

    International Nuclear Information System (INIS)

    Olsen, C.R.; Simpson, H.J.; Trier, R.M.; Columbia Univ., Palisades, NY

    1981-01-01

    Anthropogenic radionuclides have reached the Hudson estuary as global fallout from nuclear weapons testing and through local releases from commercial nuclear reactors. Significant activities of 238 Pu and 239 , 240 Pu (fallout-derived), 134 Cs and 60 Co (reactor-released), and 137 Cs (derived from both sources), have accumulated in the sediments throughout the estuary, with the primary zone of accumulation near the downstream end of the system in New York harbor. The estuary appears to have trapped nearly all of the 239 , 240 Pu delivered as fallout, and consequently, ocean dumping of dredged harbor sediment is currently the primary means for the net transport of these nuclides to coastal waters. In contrast, only 10-30% of the 137 Cs, 134 Cs and 60 Co delivered to the estuary have been retained on the fine particles which accumulate at a rapid rate in the harbor. (orig./HAE)

  19. Tsunami hazard assessment in the Hudson River Estuary based on dynamic tsunami-tide simulations

    Science.gov (United States)

    Shelby, Michael; Grilli, Stéphan T.; Grilli, Annette R.

    2016-12-01

    This work is part of a tsunami inundation mapping activity carried out along the US East Coast since 2010, under the auspice of the National Tsunami Hazard Mitigation program (NTHMP). The US East Coast features two main estuaries with significant tidal forcing, which are bordered by numerous critical facilities (power plants, major harbors,...) as well as densely built low-level areas: Chesapeake Bay and the Hudson River Estuary (HRE). HRE is the object of this work, with specific focus on assessing tsunami hazard in Manhattan, the Hudson and East River areas. In the NTHMP work, inundation maps are computed as envelopes of maximum surface elevation along the coast and inland, by simulating the impact of selected probable maximum tsunamis (PMT) in the Atlantic ocean margin and basin. At present, such simulations assume a static reference level near shore equal to the local mean high water (MHW) level. Here, instead we simulate maximum inundation in the HRE resulting from dynamic interactions between the incident PMTs and a tide, which is calibrated to achieve MHW at its maximum level. To identify conditions leading to maximum tsunami inundation, each PMT is simulated for four different phases of the tide and results are compared to those obtained for a static reference level. We first separately simulate the tide and the three PMTs that were found to be most significant for the HRE. These are caused by: (1) a flank collapse of the Cumbre Vieja Volcano (CVV) in the Canary Islands (with a 80 km3 volume representing the most likely extreme scenario); (2) an M9 coseismic source in the Puerto Rico Trench (PRT); and (3) a large submarine mass failure (SMF) in the Hudson River canyon of parameters similar to the 165 km3 historical Currituck slide, which is used as a local proxy for the maximum possible SMF. Simulations are performed with the nonlinear and dispersive long wave model FUNWAVE-TVD, in a series of nested grids of increasing resolution towards the coast, by one

  20. Sources of heavy metals in sediments of the Hudson River Estuary

    International Nuclear Information System (INIS)

    Williams, S.C.; Simpson, H.J.; Olsen, C.R.; Bopp, R.F.

    1978-01-01

    Sediments in the Hudson Estuary contain zinc, copper and lead from metal pollutants discharged to the harbor in the New York City area, from dispersed sources of contamination introduced upstream, and from natural weathering processes. The magnitude of the contribution from each of these three sources to particular sites can be estimated on the basis of total metal abundances, relative proportions of several metals, and other sediment properties. The pattern of recent heavy-metal contamination in Hudson sediments closely follows the distribution in sediments of 137 Cs which was derived over the past two decades from global fallout and local releases from a commercial nuclear reactor. Several simple empirical corrections related to grain size and mineralogy variations are suggested for comparing heavy-metal contamination levels of sandy continental shelf sediments with fine-grained estuarine and coastal sediments. Iron has little variation in Hudson sediments while manganese is greater in surface sediment of some low-salinity and fresh-water areas than deeper in the sediments, and generally less in the high-salinity area of rapid sediment deposition in New York harbor. Much of the pollutant Cu added to the harbor appears to be rapidly deposited in the sediments. (Auth.)

  1. Sources, distribution, and mobility of plutonium and radiocesium in soils, sediments and water of the Hudson River Estuary and watershed

    International Nuclear Information System (INIS)

    Linsalata, P.

    1984-01-01

    Results of 239 240 Pu, 238 Pu and 137 Cs measurements are reported for soil cores sampled within the watershed, for many sediment cores and surface dredge samples taken along the length of the Hudson River Estuary and for water samples collected on a continuous basis in both fresh and estuarine reaches. Accumulations of 239 240 Pu and 137 Cs measured within sediment cores taken from discrete regions of the river-estuary were summed to arrive at total sediment inventories of 1.6 +/- 0.7 Ci and 53 +/- 20 Ci, respectively. The variability observed in the sediment accumulation of radionuclides is discussed in terms of the physical and chemical characteristics of the river-estuary. Plutonium-239,240 and 137 Cs were similary distributed in sediments and water sampled from fresh water reaches of the Hudson with activity ratios (i.e., 239 240 Pu/ 1 2number 7 Cs) ranging from 0.01 to 0.03. Distribution coefficients, which were determined both in vitro and in situ were similar for both nuclides (i.e., from 1 x 10 5 to 3 x 10 5 L.kg -1 ) in fresh water, but diverged significantly (as a result of increased 137 Cs solubility) in brackish waters that exhibited chlorinities in excess of 1-2 g Cl - .L -1 . The concentrations of 239 240 Pu and 137 Cs observed in fresh water samples were primarily functions of the suspended load. Approximately 60-70% of the annual downstream transport of 239 240 Pu and 137 Cs calculated during 1980 and 1981 (i.e., 4 +/- 0.5 mCi and 515 +/- 84 mCi, respectively) was associated with suspended particulates greater than or equal to 0.45 μm. An empirical model was developed to determine the rates of vertical migration of these nuclides in soils of the watershed

  2. Biological effects of simulated discharge plume entrainment at Indian Point Nuclear Power Station, Hudson River estuary, USA

    International Nuclear Information System (INIS)

    Lanza, G.R.; Lauer, G.J.; Ginn, T.C.; Storm, P.C.; Zubarik, L.; New York Univ., N.Y.

    1975-01-01

    Laboratory and field simulations of the discharge plume entrainment of phytoplankton, zooplankton and fish were carried out at the Indian Point Nuclear Station, Hudson River estuary, USA. Phytoplankton assemblages studied on two dates produced different response patterns measured as photosynthetic activity. Chlorophyll-a levels did not change following simulated entrainment. Possible explanations for the differences are discussed. The two abundant copepods Acartia tonsa and Eurytemorta affinis appear to tolerate exposure to discharge plume ΔT without adverse effects. Copepods subjected to plume entrainment may suffer considerable mortality during periods of condenser chlorination. In general, the amphipod Gammarus spp. did not appear to suffer significant mortality during simulated entrainment. Juvenile striped bass, Morone saxatilis, were not affected by simulated plume transit before and during plant condenser chlorination; however, a simulated ''worst possible case'' plume ΔT produced statistically significant moralities. (author)

  3. Microstructure, CTD and ADCP data collected from R/V ONRUST in Hudson River Estuary during 6 short cruises from 1994-05-19 to 2001-05-01 (NCEI Accession 0146260)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Observations of turbulent mixing, stratification and currents in the Hudson River Estuary made in 6 short cruises in 1994/1995 and 2001 were assembled. The lower...

  4. Ecological carryover effects associated with partial migration in white perch (Morone americana) within the Hudson River Estuary

    Science.gov (United States)

    Gallagher, Brian K.; Piccoli, Philip M.; Secor, David H.

    2018-01-01

    Partial migration in complex life cycles allows environmental conditions experienced during one life-stage to interact with genetic thresholds and produce divergent spatial behaviors in the next stage. We evaluated partial migration over the entire life cycle of white perch, (Morone americana) within the Hudson River Estuary, combining otolith microchemistry, population demographics and environmental data analysis. Ecological carryover effects were used as a framework to test how environmental variation during the larval period influenced migration behaviors and growth characteristics in subsequent life-stages. Two annual cohorts of juveniles were classified based on whether they persisted in natal habitats (freshwater resident contingent) or dispersed into non-natal habitats (brackish water migratory contingent) as juveniles. The migratory contingent tended to hatch earlier and experience cooler temperatures as larvae, while the availability of zooplankton prey during the larval period appeared to influence growth dynamics before and after metamorphosis. Juvenile migration behaviors were reversible but usually persisted into adulthood. As juveniles, the consequences of partial migration on growth appeared to be modified by river flow, as demonstrated by the influence of a large storm event on feeding conditions in one of the study years. Migratory adults grew faster and attained larger maximum sizes, but may also experience higher rates of mortality. The interplay uncovered between life-stage transitions, conditional migration behaviors and habitat productivity throughout the life cycle shapes white perch population dynamics and will likely play an important role in responses to long-term environmental change.

  5. Plutonium, cesium and uranium series radionuclides in the Hudson River estuary and other environments. Annual technical progress report, 1 December 1980-30 November 1981

    International Nuclear Information System (INIS)

    Simpson, H.J.; Trier, R.M.

    1981-01-01

    Radionuclide activities were measured in sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of 137 Cs, 134 Cs, 60 Co, 239 240 Pu, and 238 Pu indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City, resulting in 239 240 Pu accumulations there more than an order of magnitude greater than the fallout delivery rate. Fallout 239 240 Pu reaching the Hudson is almost completely retained within the systems by particle deposition, while 80 to 90% of the 137 Cs derived from both reactor releases and fallout is exported to the coastal waters in solution. Depth profiles of radionuclides in Hudson sediments are not significantly altered by physical mixing processes in the sediments in areas accumulating particles at greater than 1 cm/yr. Measurements of fallout 239 2 xperimental quantities

  6. Plutonium, cesium, uranium and thorium series radionuclides in the Hudson River estuary and other environments. Annual technical progress report, 1 December 1984-30 November 1985

    International Nuclear Information System (INIS)

    Simpson, H.J.; Trier, R.M.; Anderson, R.F.

    1985-01-01

    We have measured radionuclide activities in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of 137 Cs, 134 Cs and 60 Co determined by gamma spectrometry and /sup 239,240/Pu and 238 Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City, resulting in /sup 239,240/Pu accumulations there more than an order of magnitude greater than the fallout delivery rate. Fallout /sup 239,240/Pu moving downstream in the Hudson appears to be almost completely retained within the system by particle deposition, while more than 50% of the 137 Cs derived from both reactor releases and fallout has been exported from the tidal Hudson to coastal waters. Some significant movement of dissolved plutonium into the estuary from the adjacent coastal waters may well be occurring. Depth profiles of radionuclides in Hudson sediments do not appear to be significantly altered by physical mixing processes in the sediment in areas accumulating particles at greater than 1 cm/y. Transport of fallout radionuclides from the drainage basin to the tidal Hudson appears to have decreased much faster than would be calculated from continuous removal from a well-mixed soil reservoir, indicating that sequestering of a substantial portion of the soil fallout burden has occurred in the watershed soils over the past two decades. Activities of 60 Co in New York harbor sediments in 1984 averaged considerably higher than in 1979 and 1981, suggesting releases of this nuclide to the Hudson comparable to the first five years of reactor operations. 12 figs., 9 tabs

  7. Natural activity in Hudson River estuary samples and their influence on the detection limits for gamma emitting radionuclides using NaI gamma spectrometry

    International Nuclear Information System (INIS)

    Wrenn, M.E.; Jinks, S.M.; Hairr, L.M.; Paschoa, A.S.; Lentsch, J.W.

    1972-01-01

    Sources of natural radioactivity in Hudson River Estuary are described. The technique of analysis for gamma spectrometry of environmental samples is presented and its pros and cons discussed. The distribution of natural radioactivity in water, biota and sediment was reported as well as the role played by the vertical distribution of cesium-137 in sediments as an indicator of the rate of sedimentation. The effect of the presence of natural radionuclides on the detection limits of man-made nuclides in the Hudson River environment is thoroughly examined. The results obtained with a 4-in. sodium iodide well crystal housed in a low background mercury shielding compare favorably with a more sophisticated Ge(Li) system which uses anticoincidence, as far as the analysis of environmental samples is concerned. (U.S.)

  8. Plutonium, cesium, uranium, and thorium series radionuclides in the Hudson River estuary and other environments. Annual technical progress report, December 1, 1982-November 30, 1983

    International Nuclear Information System (INIS)

    Simpson, H.J.; Trier, R.M.; Anderson, R.F.

    1983-01-01

    We have measured radionuclide activities in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of 137 Cs, 134 Cs and 60 Co determined by gamma spectrometry and 239 240 Pu and 238 Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City, resulting in 239 240 Pu accumulations there more than an order of magnitude greater than the fallout delivery rate. Fallout 239 240 Pu moving downstream in the Hudson appears to be almost completely retained within the system by particle deposition, while more than 50% of the 137 Cs derived from both reactor releases and fallout has been exported from the tidal Hudson to coastal waters. Measurements of fallout 239 240 Pu in a saline lake with a high carbonate ion concentration yielded water column activities about two orders of magnitude greater than has been found for fallout plutonium in other continental waters, indicating extensive mobility in some natural water environments. Experiments using lake water suggest that carbonate ion is likely to be a critical factor in regulating plutonium solubility in some environments and that low molecular weight complexes are primarily responsible for enhanced plutonium solubility. 5 references

  9. Geographic variability in amoeboid protists and other microbial groups in the water column of the lower Hudson River Estuary (New York, USA)

    Science.gov (United States)

    Juhl, Andrew R.; Anderson, O. Roger

    2014-12-01

    In comparison to other groups of planktonic microorganisms, relatively little is known about the role of amoeboid protists (amebas) in planktonic ecosystems. This study describes the first geographic survey of the abundance and biomass of amebas in an estuarine water column. Samples collected in the lower Hudson River Estuary were used to investigate relationships between ameba abundance and biomass and hydrographic variables (temperature, salinity, and turbidity), water depth (surface and near bottom), distance from mid-channel to shore, phytoplankton biomass (chlorophyll fluorescence) and the occurrence of other heterotrophic microbial groups (heterotrophic bacteria, nanoflagellates, and ciliates) in the plankton. Although salinity increased significantly towards the mouth of the estuary, there were no significant differences in the abundance or biomass of any microbial group in surface samples collected at three stations separated by 44 km along the estuary's mid-channel. Peak biomass values for all microbial groups were found at the station closest to shore, however, cross-channel trends in microbial abundance and biomass were not statistically significant. Although ameba abundance and biomass in most samples were low compared to other microbial groups, clear patterns in ameba distribution were nevertheless found. Unlike other microbial groups examined, ameba numbers and biomass greatly increased in near bottom water compared to surface samples. Ameba abundance and biomass (in surface samples) were also strongly related to increasing turbidity. The different relationships of ameba abundance and biomass with turbidity suggest a rising contribution of large amebas in microbial communities of the Hudson estuary when turbidity increases. These results, emphasizing the importance of particle concentration as attachment and feeding surfaces for amebas, will help identify the environmental conditions when amebas are most likely to contribute significantly to estuarine

  10. Plutonium and cesium radionuclides in the Hudson River estuary. Annual technical progress report, December 1, 1976--November 30, 1977

    International Nuclear Information System (INIS)

    Simpson, H.J.; Trier, R.M.

    1977-01-01

    We have obtained a large set of sediment cores from the Hudson estuary through much of the ambient salinity range. A number of core sections and samples of suspended particles have been analyzed for 137 Cs, 134 Cs and 60 Co by direct gamma counting, and 239 Pu, 240 Pu, and 238 Pu by alpha spectrometry. The distribution of both 137 Cs and 239 Pu, 240 Pu indicates rapid accumulation in marginal cover areas, and especially in the harbor region adjacent to New York City. The distributions of both 137 Cs and 239 Pu, 240 Pu are similar in surface sediments and with depth in cores, but there are deviations from the fallout ratio due to addition of reactor 137 Cs and loss of 137 Cs from the particle phases at higher salinities. Measureable amounts of reactor-derived 134 Cs and 60 Co are found in nearly all sediment samples containing appreciable 137 Cs, between 15 km upstream of Indian Point and the downstream extent of our sampling, 70 km south of the reactor. Accumulations of 239 Pu, 240 Pu in New York harbor sediments are more than an order of magnitude greater than the fallout delivery rate. The most likely explanation is accumulation of fine particles in the harbor which have been transported from upstream areas of the Hudson. Our evidence so far indicates that Indian Point is probably not a significant source of 239 Pu, 240 Pu or 238 Pu compared with the fallout burden of these nuclides already in the sediments

  11. Plutonium and cesium radionuclides in the Hudson River Estuary. Annual technical progress report, 1 December 1975--30 November 1976

    International Nuclear Information System (INIS)

    Simpson, H.J.; Williams, S.C.

    1976-01-01

    We have obtained a large set of cores from the Hudson Estuary covering nearly all of the ambient salinity range. A number of core sections have been analyzed for 137 Cs, 134 Cs, 60 Co and 40 K by direct gamma counting and for 239 , 240 Pu and 238 Pu by alpha-spectrometry. Rapid accumulation, up to 20 cm/year, of sediments containing 239 , 240 Pu, 137 Cs, 134 Cs and 60 Co occurs in New York Harbor. Marginal coves upstream from the harbor also serve as depositional environments. The ratio of sediment /sup 239,240/Pu to 137 Cs is higher than the fallout ratio in the seaward end of New York Harbor, despite the presence of a significant component of reactor 137 Cs in the sediments, but lower than the range of ratios observed by others for nearshore environments with low sediment deposition rates. A substantial portion of gamma emitting fission product and activation nuclides released from the Indian Point nuclear facility have accumulated in New York Harbor, more than 60 km downstream from the release area. We have not yet established whether local transuranic releases to the Hudson have occurred

  12. Hudson River Sub_Bottom Profile Data - Raw SEG-Y Files (*.sgy)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hudson River Estuary Shallow Water Surveys. Subbottom data was collected November 5 to December 15, 2009, in the estuary north from Saugerties to Troy. Data...

  13. Plutonium, cesium and uranium series radionuclides in the Hudson River estuary and other environments. Annual technical progress report, December 1, 1979-November 30, 1980

    International Nuclear Information System (INIS)

    Simpson, H.J.; Trier, R.M.; Olsen, C.R.

    1980-01-01

    Radionuclide activities were measured in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of 137 Cs, 134 Cs and 60 Co determined by gamma spectrometry and 239 240 Pu and 238 Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City, resulting in 239 240 Pu accumulations there more than an order of magnitude greater than the fallout delivery rate. Measurable amounts of reactor-derived 134 Cs and 60 Co are found in nearly al sediment samples containing appreciable 137 Cs between 15 km upstream of Indian Point and the downstream extent of our sampling about 70 km south of the reactor. Fallout 239 240 Pu reaching the Hudson appears to be almost completely retained within the systems by particle deposition, while 70 to 90% of the 137 Cs derived from both reactor releases and fallout has been exported to the coastal waters in solution. Activity levels of 239 240 Pu in New York harbor sediments indicate a significant source in addition to suspended particles carried down the Hudson. The most likely cause appears to be transport into the estuary of particles from offshore waters having higher specific activities of 239 240 Pu. Measurements of fallout 239 240 Pu in a saline lake with a high carbonate ion concentration yielded water column activities about two orders of magnitude greater than has been found for fallout plutonium in other continental waters, indicating extensive mobility in some natural water environments. Experiments using lake water suggest that carbonate ion may indeed be a critical factor in regulating plutonium solubility and that low molecular weight complexes are primarily responsible for enhanced plutonium solubility

  14. Plutonium, cesium and uranium series radionuclides in the Hudson River estuary and other environments. Annual technical progress report, December 1, 1979-November 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, H. J.; Trier, R. M.; Olsen, C. R.

    1980-01-01

    Radionuclide activities were measured in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of /sup 137/Cs, /sup 134/Cs and /sup 60/Co determined by gamma spectrometry and /sup 239/ /sup 240/Pu and /sup 238/Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City, resulting in /sup 239/ /sup 240/Pu accumulations there more than an order of magnitude greater than the fallout delivery rate. Measurable amounts of reactor-derived /sup 134/Cs and /sup 60/Co are found in nearly al sediment samples containing appreciable /sup 137/Cs between 15 km upstream of Indian Point and the downstream extent of our sampling about 70 km south of the reactor. Fallout /sup 239/ /sup 240/Pu reaching the Hudson appears to be almost completely retained within the systems by particle deposition, while 70 to 90% of the /sup 137/Cs derived from both reactor releases and fallout has been exported to the coastal waters in solution. Activity levels of /sup 239/ /sup 240/Pu in New York harbor sediments indicate a significant source in addition to suspended particles carried down the Hudson. The most likely cause appears to be transport into the estuary of particles from offshore waters having higher specific activities of /sup 239/ /sup 240/Pu. Measurements of fallout /sup 239/ /sup 240/Pu in a saline lake with a high carbonate ion concentration yielded water column activities about two orders of magnitude greater than has been found for fallout plutonium in other continental waters, indicating extensive mobility in some natural water environments. Experiments using lake water suggest that carbonate ion may indeed be a critical factor in regulating plutonium solubility and that low molecular weight complexes are primarily responsible for enhanced plutonium solubility.

  15. Plutonium and cesium radionuclides in the Hudson River Estuary. Annual technical progress report, December 1, 1974--November 30, 1975

    International Nuclear Information System (INIS)

    Simpson, H.J.; Williams, S.C.

    1975-01-01

    We have obtained a large set of gravity cores from the Hudson Estuary through much of the ambient salinity range. A number of core sections have been analyzed for 137 Cs, 134 Cs, 60 Co, and 40 K by direct gamma counting, and for 239 , 240 Pu by alpha-spectrometry. The distribution of both 137 Cs and 239 , 240 Pu indicates rapid accumulation in marginal cove areas and in the harbor region adjacent to New York City. The distribution of both 137 Cs and 239 , 240 Pu in the sediments is quite similar in surface sediments, and the trends with depth in cores are also similar. The ratio of sediment 239 , 240 Pu to 137 Cs throughout the sampled salinity range (0-20 0 / 00 ) approximates that in fallout, except near the nuclear reactor at Indian Point where releases of 137 Cs result in a ratio lower (0.004 to 0.008) than typical of fallout (0.015). Measurement amounts of reactor-derived 134 Cs, 60 Co, and 54 Mn are found in nearly all of the samples containing appreciable 137 Cs. These samples were between 15 km upstream of Indian Point reactor site and the downstream extent of our sampling, 70 km south of the reactor

  16. Dating sediment cores from Hudson River marshes

    International Nuclear Information System (INIS)

    Robideau, R.; Bopp, R.F.

    1993-01-01

    There are several methods for determining sediment accumulation rates in the Hudson River estuary. One involves the analysis of the concentration of certain radionuclides in sediment core sections. Radionuclides occur in the Hudson River as a result of: natural sources, fallout from nuclear weapons testing and low level aqueous releases from the Indian Point Nuclear Power Facility. The following radionuclides have been studied in the authors work: Cesium-137, which is derived from global fallout that started in the 1950's and has peaked in 1963. Beryllium-7, a natural radionuclide with a 53 day half-life and found associated with very recently deposited sediments. Another useful natural radionuclide is Lead-210 derived from the decay of Radon-222 in the atmosphere. Lead-210 has a half-life of 22 years and can be used to date sediments up to about 100 years old. In the Hudson River, Cobalt-60 is a marker for Indian Point Nuclear Reactor discharges. The author's research involved taking sediment core samples from four sites in the Hudson River Estuarine Research Reserve areas. These core samples were sectioned, dried, ground and analyzed for the presence of radionuclides by the method of gamma-ray spectroscopy. The strength of each current pulse is proportional to the energy level of the gamma ray absorbed. Since different radionuclides produce gamma rays of different energies, several radionuclides can be analyzed simultaneously in each of the samples. The data obtained from this research will be compared to earlier work to obtain a complete chronology of sediment deposition in these Reserve areas of the river. Core samples may then by analyzed for the presence of PCB's, heavy metals and other pollutants such as pesticides to construct a pollution history of the river

  17. Plutonium and cesium radionuclides in the Hudson River Estuary and other environments. Annual technical progress report, 1 December 1977--30 November 1978

    International Nuclear Information System (INIS)

    Simpson, H.J.; Trier, R.M.

    1978-01-01

    Radionuclide activities were measured in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of 137 Cs, 134 Cs, and 60 Co determined by gamma spectrometry and 239 , 240 Pu and 238 Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City. General distributions of 137 Cs and 239 , 240 Pu are similar in surface sediments and with depth in cores, but there are deviations from the fallout ratio due to (1) addition of reactor 137 Cs and (2) loss of 137 Cs from the particle phases at higher salinities. Measurable amounts of reactor-derived 134 Cs and 60 Co are found in nearly all sediment samples containing appreciable 137 Cs between 15 Km upstream of Indian Point and 70 Km south of the reactor. Accumulations of 239 , 240 Pu in New York harbor sediments are more than an order of magnitude greater than the fallout delivery rate. Depth profiles of radionuclides and variations of activities with particle size at low salinities in the Hudson indicate the importance of organic phases, including large flocculent particles greater than 180μ, in binding plutonium, and no evidence of significant chemical migration within the sediments. Measurements of water column fallout 239 , 240 Pu in a saline lake with a high carbonate ion concentration yielded activities about two orders of magnitude greater than has been found for fallout plutonium in other continental waters, indicating extensive mobility in some natural water environments

  18. Plutonium, cesium, uranium, and thorium series radionuclides in the Hudson River estuary and other environments. Annual technical progress report, December 1, 1981-November 30, 1982

    International Nuclear Information System (INIS)

    Simpson, H.J.; Trier, R.M.; Anderson, R.F.

    1982-01-01

    Radionuclide activities were measured in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of 137 Cs, 134 Cs and 60 Co determined by gamma spectrometry and 239 240 Pu and 238 Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City, resulting in 239 240 Pu accumulations there more than an order of magnitude greater than the fallout delivery rate. Fallout 239 240 Pu moving downstream in the Hudson appears to be almost completely retained within the system by particle deposition, while 80 to 90% of the 137 Cs derived from both reactor releases and fallout has been exported to the coastal waters in solution. Measurements of fallout 239 240 Pu in a saline lake with a high carbonate ion concentration yielded water column activities about two orders of magnitude greater than has been found for fallout plutonium in other continental waters, indicating extensive mobility in some natural water environments. Experiments using lake water suggest that carbonate ion is likely to be a critical factor in regulating plutonium solubility in some environments and that low molecular weight complexes are primarily responsible for enhanced plutonium solubility. Activities of several other nuclides of interest in radioactive waste management ( 238 U, 234 U, 232 Th, 230 Th, 228 Th, 231 Pa) were also found to be orders of magnitude greater in high carbonate waters than in other natural waters

  19. Plutonium and cesium radionuclides in the Hudson River estuary and other environments. Annual technical progress report, December 1, 1978-November 30, 1979

    International Nuclear Information System (INIS)

    Simpson, H.J.; Trier, R.M.

    1979-01-01

    Radionuclide activities were measured in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of 137 Cs, 134 Cs and 60 Co determined by gamma spectrometry and 239 240 Pu and 238 Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City. General distributions of 137 Cs and 239 240 Pu are similar in surface sediments and with depth in cores, but there are deviations from the fallout ratio due to addition of reactor 137 Cs and loss of 137 Cs from the particle phases at higher salinities. Measurable amounts of reactor-derived 134 Cs and 60 Co are found in nearly all sediment samples containing appreciable 137 Cs between 15 km upstream of Indian Point and the downstream of our sampling about 70 km south of the reactor. Accumulations of 239 240 Pu in New York harbor sediments are more than an order of magnitude greater than the fallout delivery rate, probably primarily due to the accumulation of fine particles containing fallout plutonium in the harbor which have been transported from upstream areas of the Hudson. Measurements of fallout 239 240 Pu in a saline lake with a high carbonate ion concentration yielded water column activities about two orders of magnitude greater than has been found for fallout plutonium in other continental waters, indicating extensive mobility in some natural water environments. Experiments using lake water suggest that carbonate ion may indeed be a critical factor in regulatory plutonium solubility

  20. Plutonium and cesium radionuclides in the Hudson River estuary and other environments. Annual technical progress report, December 1, 1978-November 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, H. J.; Trier, R. M.

    1979-01-01

    Radionuclide activities were measured in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of /sup 137/Cs, /sup 134/Cs and /sup 60/Co determined by gamma spectrometry and /sup 239/ /sup 240/Pu and /sup 238/Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City. General distributions of /sup 137/Cs and /sup 239/ /sup 240/Pu are similar in surface sediments and with depth in cores, but there are deviations from the fallout ratio due to addition of reactor /sup 137/Cs and loss of /sup 137/Cs from the particle phases at higher salinities. Measurable amounts of reactor-derived /sup 134/Cs and /sup 60/Co are found in nearly all sediment samples containing appreciable /sup 137/Cs between 15 km upstream of Indian Point and the downstream of our sampling about 70 km south of the reactor. Accumulations of /sup 239/ /sup 240/Pu in New York harbor sediments are more than an order of magnitude greater than the fallout delivery rate, probably primarily due to the accumulation of fine particles containing fallout plutonium in the harbor which have been transported from upstream areas of the Hudson. Measurements of fallout /sup 239/ /sup 240/Pu in a saline lake with a high carbonate ion concentration yielded water column activities about two orders of magnitude greater than has been found for fallout plutonium in other continental waters, indicating extensive mobility in some natural water environments. Experiments using lake water suggest that carbonate ion may indeed be a critical factor in regulatory plutonium solubility.

  1. Plutonium, cesium, uranium and thorium series radionuclides in the Hudson River estuary and other environments. Annual technical progress report, December 1, 1983-November 30, 1984

    International Nuclear Information System (INIS)

    Simpson, H.J.; Trier, R.M.; Anderson, R.F.

    1984-01-01

    Radionuclide activities were measured in sediment cores and suspended particle samples from the Hudson River estuary. Activities of 137 Cs, 134 Cs, and 60 Co, 239 240 Pu and 238 Pu indicate rapid accumulation in marginal cove areas, and very rapid deposition in the harbor adjacent to New York City, resulting in 239 240 Pu accumulations of more than an order of magnitude greater than the fallout delivery rate. Fallout 239 240 Pu moving downstream appears to be retained within the system by particle deposition, while more than 50% of the 137 Cs derived from both reactor releases and fallout has been exported. Significant movement of dissolved plutonium into the estuary from adjacent coastal waters may be occurring. Depth profiles of radionuclides are not significantly altered by physical mixing processes in areas accumulating particles at greater than 1 cm/yr. Transport of fallout radionuclides appears to have decreased faster than would be calculated from continuous removal from a well-mixed soil reservoir, indicating that sequestering of a substantial portion of the soil fallout burden has occurred in the watershed soils over the past two decades. Measurements of fallout 239 240 Pu in a saline lake with a high carbonate ion concentration yielded water column activities two orders of magnitude greater than that found for fallout plutonium in other continental waters, indicating extensive mobility in some natural water environments. Experiments using lake water suggest that carbonate ions are likely to be important in regulating plutonium solubility in some environments and that low molecular weight complexes are primarily responsible for enhanced plutonium solubility. 45 references, 17 figures, 14 tables

  2. Nelson River and Hudson Bay

    Science.gov (United States)

    2002-01-01

    Rivers that empty into large bodies of water can have a significant impact on the thawing of nearshore winter ice. This true-color Moderate Resolution Imaging Spectroradiometer (MODIS) image from May 18, 2001, shows the Nelson River emptying spring runoff from the Manitoba province to the south into the southwestern corner of Canada's Hudson Bay. The warmer waters from more southern latitudes hasten melting of ice near the shore, though some still remained, perhaps because in shallow coastal waters, the ice could have been anchored to the bottom. High volumes of sediment in the runoff turned the inflow brown, and the rim of the retreating ice has taken on a dirty appearance even far to the east of the river's entrance into the Bay. The sediment would have further hastened the melting of the ice because its darker color would have absorbed more solar radiation than cleaner, whiter ice. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  3. 27 CFR 9.47 - Hudson River Region.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Hudson River Region. 9.47... Hudson River Region. (a) Name. The name of the viticultural area described in this section is “Hudson River Region.” (b) Approved maps. The approved maps for determining the boundaries of Hudson River...

  4. 77 FR 22530 - Safety Zone; Fireworks, Hudson River, Rhinecliff, NY

    Science.gov (United States)

    2012-04-16

    ...-AA00 Safety Zone; Fireworks, Hudson River, Rhinecliff, NY AGENCY: Coast Guard, DHS. ACTION: Notice of... navigable waters of the Hudson River in the vicinity of Rhinecliff, NY for a fireworks display. This... fireworks displays. This rule is intended to restrict all vessels from a portion of the Hudson River before...

  5. Hudson River settlement agreement: Technical rationale and cost considerations

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Boreman, J.; Englert, T.L.; Kirk, W.L.; Horn, E.G.

    1988-01-01

    In an effort to end litigation over open-cycle cooling at Hudson River power plants, out-of-court negotiations began in August 1979. On December 19, 1980, an agreement that was acceptable to all parties was reached. As an alternative to building cooling towers at the Indian Point, Bowline Point, and Roseton generating stations, the utilities agreed to a variety of technical and operational changes intended to reduce entrainment and impingement. In addition, they agreed to supplement the production of striped bass in the Hudson River estuary by means of a hatchery, to conduct a biological monitoring program, and to fund an independent research foundation for study of Hudson River environmental problems. Although the settlement costs were substantial, they were much smaller than the estimated costs of constructing and operating cooling towers. The settlement was expected to provide 15-43% of the impact reduction that might have been obtained with cooling at approximately 10% of the cost. 20 refs., 3 tabs

  6. Stock characteristics of Hudson River striped bass

    International Nuclear Information System (INIS)

    Hoff, T.B.; McLaren, J.B.; Cooper, J.C.

    1988-01-01

    Striped bass, because of their tremendous popularity both commercially and recreationally, were a principal focus of the Hudson River power plant case. Between 1976 and 1979, over 23,000 age-II and older striped bass were studied as one facet of an extensive research program on the spring population in the Hudson River. Samples were collected from the overwintering as well as the spawning portion of the striped bass population, and included immature as well as mature fish. At least 12 age-groups contributed to spawning each year. Of these 12, age-groups III, IV, and V usually were most abundant, but the percentage of the population represented by any single age-group varied as the result of fluctuations in year-class strength. Males first became sexually mature at age II and females at age IV. Fast-growing individuals within a year class tended to mature earlier. Fecundity increased with the size of fish, reaching an observed maximum of about 3 million eggs per female. Although significant annual variations in maturity and growth were detected for Hudson River striped bass, there was no evidence of a consistent change in either variable that might be associated with increasing power plant operations and a reduction in striped bass abundance. Age at maturity and age structure are the two life history components that differ the most between the Hudson River population and other striped bass populations. 36 refs., 7 tabs

  7. Sediment mixing and accumulation rate effects on radionuclide depth profiles in Hudson estuary sediments

    International Nuclear Information System (INIS)

    Olsen, C.R.; Simpson, H.J.; Peng, T.; Bopp, R.F.; Trier, R.M.

    1981-01-01

    Measured anthropogenic radionuclide profiles in sediment cores from the Hudson River estuary were compared with profiles computed by using known input histories of radionuclides to the estuary and mixing coefficients which decreased exponentially with depth in the sediment. Observed 134 Cs sediment depth profiles were used in the mixing rate computation because reactor releases were the only significant source for this nuclide, whereas the inputs of 137 Cs and /sup 239.240/Pu to the estuary were complicated by runoff or erosion in upstream areas, in addition to direct fallout from precipitation. Our estimates for the rates of surface sediment mixing in the low salinity reach of the estuary range from 0.25 to 1 cm 2 /yr, or less. In some areas of the harbor adjacent to New York City, were fine-particle accumulation rates are generally >3 cm/yr, and often as high as 10 to 20 cm/yr, sediment mixing rates as high as 10 cm 2 /yr would have little effect on radionuclide peak distributions. Consequently, anthropogenic radionuclide maximum activities in subsurface sediments of the Hudson appear to be useful as time-stratigraphic reference levels, which can be correlated with periods of maximum radionuclide inputs for estimating rates and patterns of sediment accumulation

  8. Tests of bioaccumulation models for polychlorinated biphenyl compounds: a study of young-of-the-year bluefish in the Hudson River estuary, USA.

    Science.gov (United States)

    Leblanc, Lawrence A; Buckel, Jeffrey A; Conover, David O; Brownawell, Bruce J

    2006-08-01

    A field-based study regarding uptake of polychlorinated biphenyl compounds (PCBs) by young-of-the-year (YOY) bluefish (Pomatomus saltatrix) was initiated to test a steady-state model of bioaccumulation and trophic transfer in a rapidly growing fish. Determination of prey composition as well as size-dependent growth and specific consumption rates for YOY bluefish from separate field and laboratory studies enabled the input of these species-specific parameters into the model. Furthermore, the time and duration of the exposure of YOY bluefish to dissolved PCBs from a well-characterized system (Hudson River, USA) was well known. Patterns of accumulation of individual PCB congeners differed relative to the accumulation of total PCBs, with the greatest net accumulation occurring for the higher-molecular-weight congeners. Comparison of lipid-normalized bioaccumulation factors (BAFs) with the octanol-water partition coefficients of individual PCB congeners revealed bluefish to be above the BAFs predicted by lipid-based equilibrium partitioning, suggesting that uptake from food is an important source of PCBs in YOY bluefish. Comparison of measured BAFs with values predicted by a steady-state, food-chain model showed good first-order agreement.

  9. A River Summer on the Hudson

    Science.gov (United States)

    Kenna, T. C.; Pfirman, S.; Selleck, B.; Son, L.; Land, M.; Cronin, J.

    2006-12-01

    River Summer is a month-long faculty development program extending from the continental shelf off New York City to the headwaters of the Hudson in the Adirondack Mountains. During the program, faculty from the Environmental Consortium of Hudson Valley Colleges and Universities teach each other about the Hudson environment, using innovative methods of teaching and learning, with a focus on incorporation of hands-on approaches from the perspective of multiple disciplines. Over four weeks, faculty from research universities, community colleges, liberal arts institutions, and middle and high schools work and live together, on board a research vessel or in a remote tent campsite, for several days at a time. Using the geology, hydrology, and landscape of the River as a foundation, River Summer focuses on understanding development of the Hudson within the context of its natural resources and cultural history. Participants conduct field sampling and analyses and consider issues through approaches that are common to many disciplines: scaling for problem solving; sampling and assessing bias and representation; observing and documenting; representing and depicting; interpretation and assessing relationships and causality; and evaluation. They also get a chance to experience, first-hand, the complexity and often open-ended nature of doing science. By allowing individuals, many of whom come from non-science disciplines, to experience these methods and processes in a safe learning environment, science is made more meaningful and accessible. The program's pedagogy is based on the principles of cognitive psychology and immersive field-, place- and inquiry-based learning. Field programs have been found to provide memorable, transformative experiences for undergraduate students, and our experience with River Summer 2005 and 2006 suggests they are equally effective with faculty. Evaluation shows that River Summer has a significant impact on its participants. Participants develop new

  10. A History of Vegetation, Sediment and Nutrient Dynamics at Tivoli North Bay, Hudson Estuary, New York

    Science.gov (United States)

    Sritrairat, Sanpisa; Peteet, Dorothy M.; Kenna, Timothy C.; Sambrotto, Ray; Kurdyla, Dorothy; Guilderson, Tom

    2012-01-01

    We conduct a stratigraphic paleoecological investigation at a Hudson River National Estuarine Research Reserve (HRNERR) site, Tivoli Bays, spanning the past 1100 years. Marsh sediment cores were analyzed for ecosystem changes using multiple proxies, including pollen, spores, macrofossils, charcoal, sediment bulk chemistry, and stable carbon and nitrogen isotopes. The results reveal climatic shifts such as the warm and dry Medieval Warm Period (MWP) followed by the cooler Little Ice Age (LIA), along with significant anthropogenic influence on the watershed ecosystem. A five-fold expansion of invasive species, including Typha angustifolia and Phragmites australis, is documented along with marked changes in sediment composition and nutrient input. During the last century, a ten-fold sedimentation rate increase due to land-use changes is observed. The large magnitude of shifts in vegetation, sedimentation, and nutrients during the last few centuries suggest that human activities have made the greatest impact to the marshes of the Hudson Estuary during the last millennium. Climate variability and ecosystem changes similar to those observed at other marshes in northeastern and mid-Atlantic estuaries, attest to the widespread regional signature recorded at Tivoli Bays.

  11. Evidence of Spatially Extensive Resistance to PCBs in an Anadromous Fish of the Hudson River

    Science.gov (United States)

    Yuan, Zhanpeng; Courtenay, Simon; Chambers, R. Christopher; Wirgin, Isaac

    2006-01-01

    Populations of organisms that are chronically exposed to high levels of chemical contaminants may not suffer the same sublethal or lethal effects as naive populations, a phenomenon called resistance. Atlantic tomcod (Microgadus tomcod) from the Hudson River, New York, are exposed to high concentrations of polycyclic aromatic hydrocarbons (PAHs) and bioaccumulate polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs). They have developed resistance to PCBs and PCDDs but not to PAHs. Resistance is largely heritable and manifests at early-life-stage toxic end points and in inducibility of cytochrome P4501A (CYP1A) mRNA expression. Because CYP1A induction is activated by the aryl hydrocarbon receptor (AHR) pathway, as are most toxic responses to these compounds, we sought to determine the geographic extent of resistance to CYP1A mRNA induction by PCBs in the Hudson River tomcod population. Samples of young-of-the-year tomcod were collected from seven locales in the Hudson River, extending from the Battery at river mile 1 (RM 1) to RM 90, and from the Miramichi River, New Brunswick, Canada. Laboratory-reared offspring of tomcod adults from Newark Bay, in the western portion of the Hudson River estuary, were also used in this study. Fish were partially depurated in clean water and intraperitoneally injected with 10 ppm coplanar PCB-77, 10 ppm benzo[a]pyrene (BaP), or corn oil vehicle, and levels of CYP1A mRNA were determined. CYP1A was significantly inducible by treatment with BaP in tomcod from the Miramichi River, from laboratory-spawned offspring of Newark Bay origin, and from all Hudson River sites spanning 90 miles of river. In contrast, only tomcod from the Miramichi River displayed significantly induced CYP1A mRNA expression when treated with PCB-77. Our results suggest that the population of tomcod from throughout the Hudson River estuary has developed resistance to CYP1A inducibility and probably

  12. Technical descriptions of Hudson River electricity generating stations

    International Nuclear Information System (INIS)

    Hutchison, J.B.

    1988-01-01

    Six fossil-fueled and one nuclear electricity generating plants are sited along the Hudson River estuary between kilometers 8 and 228, measured from the river mouth. Their aggregate rated capacity is 5,798 MW of electricity; operating at that capacity they would withdraw cooling water from the river at the rate of 1.5 x 10 to the 9th power cu m/d and reject heat at the rate of 155 x 10 to the 9th power kcal/d. Three of these plants, the fossil-fueled Roseton and Bowline and the nuclear Indian Point facilities; account for 75% of total rated capacity, 62% of maximum water withdrawal, and 79% of potential heat rejection. These three plants and a proposed pumped-storage facility at Cornwall, all sited between km 60 and 106, were the focus of environmental litigation. The Indian Point plant normally operates at 100% generation capacity; the other plants may experience daily operating load changes that vary from approximately 50% to 100% of total generation capacity, depending on system electrical demand or economic considerations. All plants experience periodic unscheduled outages for repairs. 6 refs., 7 figs

  13. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: RVRMILES (River Mile Marker Lines)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains human-use resource data for river miles along the Hudson River. Vector lines in this data set represent river mile markers. This data set...

  14. Tetrachlorodibenzo-p-dioxins and tetrachlorodibenzofurans in Atlantic coast striped bass and in selected Hudson River fish, waterfowl and sediments

    Energy Technology Data Exchange (ETDEWEB)

    O' Keefe, P; Hilker, D; Meyer, C; Aldous, K; Shane, L; Donnelly, R; Smith, R; Sloan, R; Skinner, L; Horn, E

    1884-01-01

    In striped bass samples from the lower Hudson River and its estuary 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) was found at concentrations from 16 to 120 pg/g (ppt). Striped bass from two other locations (Rhode Island coastal waters and Chesapeake Bay, Maryland) had <5 ppt, 2,3,7,8-TCDD. The contaminant, 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF), was found in striped bass from all three locations with concentrations varying from 6 ppt in Chesapeake Bay to 78 ppt in the Hudson River. Results from a limited number of non-migratory fish (carp and goldfish) and sediments suggest that the upper Hudson River is not a source for 2,3,7,8-TCDD/2,3,7,8-TCDF contamination of striped bass. 26 references, 3 tables.

  15. Science, law, and Hudson River power plants: A case study in environmental impact assessment

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Klauda, R.J.; Vaughan, D.S.; Kendall, R.L.

    1988-01-01

    Between 1963 and 1980, the Hudson River estuary was the focus of one of the most ambitious environmental research and assessment programs ever performed. The studies supported a series of US federal proceedings involving licenses and discharge permits for two controversial electric power generating facilities: the Cornwall pumped storage facility, and units 2 and 3 of the Indian Point nuclear generating station. Both facilities were to draw large volumes of water from a region of the Hudson used as spawning and nursery habitat by several fish species, including the striped bass. Fishermen and conservationists feared that a major fraction of the striped bass eggs and larvae in the Hudson would be entrained with the pumped water and killed. Additional fish would be killed on trash screens at the intakes. Scientists were asked to aid the utility companies and regulatory agencies in determining the biological importance of entrainment and impingement. This monograph contains both technical papers that present research results and synthesis papers that summarize and interpret the results. The intent was to: (1) summarize the scientific issues and approaches; (2) present the significant results of the Hudson River biological studies; (3) describe the role of the studies in the decision-making process; (4) evaluate the successes and failures of the studies; and (5) present recommendations for future estuarine impact assessments. Separate abstracts are processed for 22 papers for inclusion in the appropriate data bases

  16. Zirconium/niobium-95 determined in Hudson River water

    International Nuclear Information System (INIS)

    Linsalata, P.; Cohen, N.

    1982-01-01

    Zirconium 95 and Niobium 95 are the fission products detected in greatest abundance in Hudson River water following the atmospheric testing of a nuclear device in N.W. China in 1980. Water samples, collected continuously and on a 'grab' basis, and processed monthly, have been studied to determine 95 Zr and 95 Nb concentrations, and plotted against collection time. Total precipitation values for each month, averaged over the whole Hudson River are also plotted. Airborne concentration data were obtained from sites in Lower Manhattan and Chester, N.J. A maximum value for 95 Zr in the Hudson River was found for February 1981. Half-time removal of 95 Zr from water was also calculated. (U.K.)

  17. 75 FR 76943 - Regulated Navigation Area; Hudson River South of the Troy Locks, NY

    Science.gov (United States)

    2010-12-10

    ...-AA11 Regulated Navigation Area; Hudson River South of the Troy Locks, NY AGENCY: Coast Guard, DHS... Navigation Area (RNA) on the navigable waters of the Hudson River in New York, south of the Troy Locks. This... within the waters of the Hudson River south of the Troy Locks when ice is a threat to navigation. DATES...

  18. 75 FR 8486 - Regulated Navigation Area; Hudson River south of the Troy Locks, New York

    Science.gov (United States)

    2010-02-25

    ...-AA11 Regulated Navigation Area; Hudson River south of the Troy Locks, New York AGENCY: Coast Guard, DHS... area on the navigable waters of the Hudson River south of the Troy Locks. This regulated navigation... Hudson River south of the Troy locks when ice conditions are 8 inches or greater unless authorized by the...

  19. 76 FR 8654 - Regulated Navigation Area; Hudson River South of the Troy Locks, NY

    Science.gov (United States)

    2011-02-15

    ...-AA11 Regulated Navigation Area; Hudson River South of the Troy Locks, NY AGENCY: Coast Guard, DHS... navigable waters of the Hudson River in New York, south of the Troy Locks. This action is necessary to... Hudson River south of the Troy Locks when ice is a threat to navigation. DATES: This rule is effective in...

  20. National Status and Trends: Bioeffects Program - Magnitude and Extent of Sediment Toxicity in the Hudson-Raritan Estuary

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A survey of the toxicity of sediments was performed by NOAA's National Status and Trends (NSandT) Program throughout the Hudson-Raritan Estuary. The objectives of...

  1. Ecological investigation of Hudson River macrozooplankton in the vicinity of a nuclear power plant

    International Nuclear Information System (INIS)

    Ginn, T.C.

    1977-01-01

    Studies were conducted on selected Hudson River macrozooplankton species to determine temporal and spatial distributions and responses to power plant operation. Distinguishing morphological and habitat characteristics were determined for the three gammarid amphipods (Gammarus daiberi, G. tigrinus, and G. fasciatus) occurring in the Hudson River. The oedicerotid amphipod Monoculodes edwardsi and the mysid Neomysis americana, in addition to the gammarid amphipods, displayed characteristic diel and seasonal abundances which affect their potential availability for power plant entrainment. The selected macrozooplankton species were utilized in temperature and chlorine bioassays in order to predict responses to cooling water entrainment. Although amphipods (Gammarus spp. and M. edwardsi) survived typical Indian Point cooling water temperatures, N. americana had high mortalities during a 30-minute, 8.3 0 C ΔT at 25 0 C ambient temperature. The bioassay results were substantiated by generally high survivals of entrained amphipods at the Indian Point plant. Neomysis americana were more heat sensitive, as indicated in bioassays, with average entrainment mortalities ranging from 30 to 60 percent during the summer. All species examined had higher immediate and latent mortalities during plant condenser chlorination. The ability of Gammarus to survive condenser passage and exposure to the Indian Point thermal discharge plume indicates that power plant operation on the lower Hudson River Estuary has no adverse impact on local gammarid amphipod populations. Entrained N. americana experience considerable mortalities; however, the impact on Atlantic Coast populations is minimized by the limited exposure of the population fringe to the Indian Point power plant

  2. Hudson River cooling tower proceeding: Interface between science and law

    International Nuclear Information System (INIS)

    Bergen, G.S.P.

    1988-01-01

    As the Hudson River power plant case proceeded, the regulatory ground shifted under the utility companies. At first, the US Environmental Protection Agency (EPA) contended that the utilities should build expensive closed-cycle cooling towers at three plants to minimize the plants' discharge of heated effluents to the river. When the formal hearing began, however, EPA claimed that cooling towers were needed to minimize the number of organisms impinged at and entrained through the plants. The Hudson River proceeding became a policy dispute over what the appropriate standard of environmental conduct should be, instead of a determination of whether a standard had been met or not. Such policy issues, which arise when legal precedent has yet to be developed for new laws like the Clean Water Act, are better addressed by a rule-making proceeding than by the adjudicatory hearing format used in the Hudson case. A rule-making proceeding would have markedly shortened the Hudson deliberations, probably without substantive change in the final settlement, and is recommended for future cases in which ambiguity in legislation or the lack of precedent has left policy matters unresolved. 2 refs

  3. Impact of impingement on the Hudson River white perch population

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Van Winkle, W.

    1980-01-01

    The impact of power plant impingement on the 1974 and 1975 year classes of the Hudson River white perch population is assessed using a simple model derived from Ricker's theory of fisheries dynamics. The impact of impingement is expressed in the model as the conditional mortality rate, rather than as the more commonly used exploitation rate. Since the calculated impact is sensitive to errors in the estimation of population size and total mortality, ranges of probable values of these quantities are used to compute upper and lower bounds on the fractional reduction in abundance of each year class. Best estimates of abundance and mortality are used to compute the conditional impingement mortality rate separately for each plant and month. The results are used to assess the relative impacts of white perch impingement at six Hudson River power plants and to identify the seasons during which the impact is highest

  4. 75 FR 38714 - Safety Zone; Macy's Fourth of July Fireworks Display, Hudson River, New York, NY

    Science.gov (United States)

    2010-07-06

    ... is scheduled to occur on the waters of the Hudson River. This temporary safety zone is necessary to... public notification. Although the temporary safety zone will apply to the entire width of the river... establishment of a temporary safety zone on a portion of the Hudson River during the launching of fireworks. An...

  5. 33 CFR 165.162 - Safety Zone: New York Super Boat Race, Hudson River, New York.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone: New York Super Boat Race, Hudson River, New York. 165.162 Section 165.162 Navigation and Navigable Waters COAST GUARD... § 165.162 Safety Zone: New York Super Boat Race, Hudson River, New York. (a) Regulated area. The...

  6. 77 FR 41271 - Safety Zone; Newburgh to Beacon Swim, Newburgh, Hudson River, NY

    Science.gov (United States)

    2012-07-13

    ... 1625-AA00 Safety Zone; Newburgh to Beacon Swim, Newburgh, Hudson River, NY AGENCY: Coast Guard, DHS... navigable waters of the Hudson River, NY in the vicinity of Newburgh, NY for the annual Newburgh Beacon Swim... Beacon Swim is an annual recurring event that has a permanent safety zone found at 33 CFR 165.160. The...

  7. The Hudson River Plume: Exploring Human Impact on the Coastal Environment

    Science.gov (United States)

    McDonnell, Janice; Duncan, Ravit; Lichtenwalner, C. Sage; Dunbar, Laura

    2010-01-01

    The Hudson River Watershed contains a variety of geologic, topographic, climatic, and hydrologic features and a diversity of land-use patterns--making it an ideal model for studying human impact on the coastal environment. In this article, the authors present the Hudson River Plume (HRP), a problem-based online module that explores nonpoint-source…

  8. 33 CFR 207.50 - Hudson River Lock at Troy, N.Y.; navigation.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Hudson River Lock at Troy, N.Y..., DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.50 Hudson River Lock at Troy, N.Y.; navigation. (a...) [Reserved] (n) Trespass on U.S. property. Trespass on U.S. property, or willful injury to the banks, masonry...

  9. 78 FR 31454 - Drawbridge Operation Regulation; Hudson River, Troy and Green Island, NY

    Science.gov (United States)

    2013-05-24

    ...-AA09 Drawbridge Operation Regulation; Hudson River, Troy and Green Island, NY AGENCY: Coast Guard, DHS... that governs the highway bridge (Troy Green Island) across the Hudson River, mile 152.7, between Troy... the regulations for the 112th Street Bridge, mile 155.4, between Troy and Cohoes which has been...

  10. 78 FR 56607 - Drawbridge Operation Regulation; Hudson River, Troy and Green Island, NY

    Science.gov (United States)

    2013-09-13

    ...-AA09 Drawbridge Operation Regulation; Hudson River, Troy and Green Island, NY AGENCY: Coast Guard, DHS... operation of the highway bridge across the Hudson River, mile 152.7, between Troy and Green Island, New York... Street Bridge, mile 155.4, between Troy and Cohoes which has been converted to a fixed bridge. It is...

  11. Impact of entrainment and impingement on fish populations in the Hudson River Estuary. Volume II. Impingement impact analyses, evaluations of alternative screening devices, and critiques of utility testimony relating to density-dependent growth, the age-composition of the striped bass spawning stock, and the LMS real-time life cycle model

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Van Winkle, W.; Golumbek, J.; Cada, G.F.; Goodyear, C.P.; Christensen, S.W.; Cannon, J.B.; Lee, D.W.

    1982-04-01

    This volume includes a series of four exhibits relating to impacts of impingement on fish populations, together with a collection of critical evaluations of testimony prepared for the utilities by their consultants. The first exhibit is a quantitative evaluation of four sources of bias (collection efficiency, reimpingement, impingement on inoperative screens, and impingement survival) affecting estimates of the number of fish killed at Hudson River power plants. The two following exhibits contain, respectively, a detailed assessment of the impact of impingement on the Hudson River white perch population and estimates of conditional impingement mortality rates for seven Hudson River fish populations. The fourth exhibit is an evaluation of the engineering feasibility and potential biological effectiveness of several types of modified intake structures proposed as alternatives to cooling towers for reducing impingement impacts. The remainder of Volume II consists of critical evaluations of the utilities' empirical evidence for the existence of density-dependent growth in young-of-the-year striped bass and white perch, of their estimate of the age-composition of the striped bass spawning stock in the Hudson River, and of their use of the Lawler, Matusky, and Skelly (LMS) Real-Time Life Cycle Model to estimate the impact of entrainment and impingement on the Hudson River striped bass population

  12. Natural radiation dose to Gammarus from Hudson river

    International Nuclear Information System (INIS)

    Paschoa, A.S.; Wrenn, M.E.; Eisenbud, M.

    1979-01-01

    The purpose of this investigation is to evaluate the natural radiation dose rate to whole body and components of the Gammarus species, a zooplankton which occurs in the Hudson River among other places, and to compare the results with the upper limits of dose rates from man-made sources. The alpha dose rates to the exoskeleton and soft tissues are about 10 times the average alpha dose rate to the whole body, assuming uniform distribution of 226 Ra. The natural alpha radiation dose rate to Gammarus represents only about 5% of the total natural dose to the organism, i.e., 492 mrad/yr. The external dose rate due to 40 K, 238 U plus daughters and 232 Th plus daughters accumulated in the sediments comprise 91% of that total natural dose rate, the remaining percentage being due to natural internal beta emitters and cosmic radiation. Man-made sources can cause an external dose rate up to 224 mrad/yr, which comprises roughly 1/3 of the total dose rate (up to 716 mrad/yr; natural plus man-made) to the Gammarus of Hudson River in front of Indian Point Nuclear Power Station. However, in terms of dose-equivalent the natural sources of radiation would contribute more than 75% of the total dose to Gammarus

  13. Historical development of entrainment models for Hudson River striped bass

    International Nuclear Information System (INIS)

    Christensen, S.W.; Englert, T.L.

    1988-01-01

    In the mid-1960s, concerns surfaced regarding entrainment and impingement of young-of-the-year (age-0) striped bass by electric power generating facilities on the Hudson River. These concerns stimulated the development of increasingly complex models to evaluate the impacts of these facilities. The earliest simplistic formulas, based on empirical data, proved inadequate because of conceptual shortcomings, incomplete development, and lack of data. By 1972, complex transport models based on biological and hydrodynamic principles had been developed and applied by scientists representing both the utilities and the government. Disagreements about the acceptability of these models spurred the development of even more complex models. The entrainment models stimulated the collection of substantial amounts of field data to define the spatial distributions and entrainment survival of early life stages. As the difficulties of accounting for the movement of early life stages from hydrodynamic principles became more evident and as more field data became available, simpler empirical modeling approaches became both practical and defensible. Both empirical and hydrodynamic modeling approaches were applied during the US Environmental Protection Agency's hearings on the Hudson River power case (1977-1980). The main lessons learned from the experience with entrainment-impingement modeling are that complex mechanistic models are not necessarily better than simpler empirical models for young fish, and that care must be taken to construct even the simple models correctly. 29 refs., 4 figs., 1 tab

  14. The Mntafufu and Mzamba River estuaries

    African Journals Online (AJOL)

    1989-03-14

    Mar 14, 1989 ... A survey of the fish fauna of Transkei estuaries. Part Four: The Mntafufu and Mzamba River estuaries. E.E. Plumstead • and J.F. Prinsloo. Department of Zoology, University of Transkei, Private Bag X1, Unitra, Umtata, Republic of Transkei. H.J. Schoonbee. Department of Zoology, Rand Afrikaans University, ...

  15. Environmental Sensitivity Index (ESI) Atlas: Hudson River, maps and geographic information systems data (NODC Accession 0014791)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) data for the Hudson River from 1942 to 2005. ESI data characterize estuarine environments and...

  16. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species in the Hudson River. Vector polygons in this...

  17. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: REPTILES (Reptile Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for estuarine reptiles (turtles, terrapins) and amphibians (salamanders, frogs) for the Hudson River....

  18. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: INVERT (Invertebrate Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine invertebrate species for the Hudson River. Vector polygons in this data set...

  19. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: STAGING (Staging Site Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains human-use resource data for staging sites along the Hudson River. Vector points in this data set represent locations of possible staging areas...

  20. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: MGT (Management Area Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive human-use data for regional and state parks, historic sites, marine sanctuaries, and other managed areas for the Hudson River....

  1. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: SENSITIV (Sensitive Area Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains human-use resource data for sensitive areas along the Hudson River. Vector points in this data set represent sensitive areas. This data set...

  2. Characterizing seston in the Penobscot River Estuary.

    Science.gov (United States)

    Meseck, Shannon L; Li, Yaqin; Sunila, Inke; Dixon, Mark; Clark, Paul; Lipsky, Christine; Stevens, Justin R; Music, Paul; Wikfors, Gary H

    2017-10-01

    The Penobscot River Estuary is an important system for diadromous fish in the Northeast United States of American (USA), in part because it is home to the largest remnant population of Atlantic salmon, Salmo salar, in the country. Little is known about the chemical and biological characteristics of seston in the Penobscot River Estuary. This study used estuarine transects to characterize the seston during the spring when river discharge is high and diadromous fish migration peaks in the Penobscot River Estuary. To characterize the seston, samples were taken in spring 2015 for phytoplankton identification, total suspended matter (TSM), percent organic TSM, chlorophyll a, particle size (2 μm-180 μm), particulate carbon and nitrogen concentrations, and stable carbon and nitrogen isotopes. The estuarine profiles indicate that TSM behaved non-conservatively with a net gain in the estuary. As phytoplankton constituted only 1/1000 of the particles, the non-conservative behavior of TSM observed in the estuary was most likely not attributable to phytoplankton. Particulate carbon and nitrogen ratios and stable isotope signals indicate a strong terrestrial, allochthonous signal. The seston in the Penobscot River Estuary was dominated by non-detrital particles. During a short, two-week time period, Heterosigma akashiwo, a phytoplankton species toxic to finfish, also was detected in the estuary. A limited number of fish samples, taken after the 2015 Penobscot River Estuary bloom of H. akashiwo, indicated frequent pathological gill damage. The composition of seston, along with ichthyotoxic algae, suggest the need for further research into possible effects upon resident and migratory fish in the Penobscot River Estuary. Published by Elsevier Ltd.

  3. Heavy metals in Mindhola river estuary, India

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Rokade, M.A; Mandalia, A

    The heavy metal concentrations are studied along the Mindhola river estuary. Surface and bottom water samples were collected using Niskin Sampler. The sediment samples were collected using a Van Veen grab. The heavy metal concentration is estimated...

  4. Improvements in Hudson River Water Quality Create the Need for a new Approach to Monitoring and Management

    Science.gov (United States)

    O'Mullan, G. D.; Juhl, A.; Sambrotto, R.; Lipscomb, J.; Brown, T.

    2008-12-01

    The lower Hudson River is a well-flushed temperate estuary that continues to support diverse wildlife populations although its shores are home to the nation's most populated metropolitan area. Data sets from the last hundred years clearly demonstrate extreme nutrient concentrations, pathogen loading, and periods of persistent hypoxia. These data also show a clear trend of steadily improving water quality in the last thirty years. Recent increases in recreational activity, expanded shoreline parks, and waterfront redevelopment, indicate the return of the people of New York to the River, concomitant with improved water quality. While mean seasonal water quality indicators are now often acceptable for large portions of the River, there remains a lack of information about the finer scale spatial and temporal variability of water quality. A new water quality sampling program was initiated in the Fall of 2006 to address this challenge. Monthly sampling cruises collected continuous underway surface measurements of hydrographic variables in parallel with discrete sampling for nutrients and microbiology. In general, these data indicate that mid-channel locations are often within acceptable water quality standards during dry weather, but that wet weather events deliver large quantities of sewage to the River, leading to short-term deterioration in water quality. In 2006-2007, only 6 of 27 sample sites had geometric mean values for Enterococcus , a sewage-indicating microorganism, that suggest consistently poor water quality. In contrast, single-day exceedances of EPA recommended guidelines for Enterococcus were found at 21 of the 27 sites. Although the mid-channel of the River was relatively homogenous with respect to sewage indicators, large changes were observed at tributary mixing interfaces and along the shallow edges of the River where human contact is most likely. The changing use of the River, together with new information about the importance of episodic and

  5. Simulating the Effects of Sea Level Rise on the Resilience and Migration of Tidal Wetlands along the Hudson River.

    Directory of Open Access Journals (Sweden)

    Nava M Tabak

    Full Text Available Sea Level Rise (SLR caused by climate change is impacting coastal wetlands around the globe. Due to their distinctive biophysical characteristics and unique plant communities, freshwater tidal wetlands are expected to exhibit a different response to SLR as compared with the better studied salt marshes. In this study we employed the Sea Level Affecting Marshes Model (SLAMM, which simulates regional- or local-scale changes in tidal wetland habitats in response to SLR, and adapted it for application in a freshwater-dominated tidal river system, the Hudson River Estuary. Using regionally-specific estimated ranges of SLR and accretion rates, we produced simulations for a spectrum of possible future wetland distributions and quantified the projected wetland resilience, migration or loss in the HRE through the end of the 21st century. Projections of total wetland extent and migration were more strongly determined by the rate of SLR than the rate of accretion. Surprisingly, an increase in net tidal wetland area was projected under all scenarios, with newly-formed tidal wetlands expected to comprise at least 33% of the HRE's wetland area by year 2100. Model simulations with high rates of SLR and/or low rates of accretion resulted in broad shifts in wetland composition with widespread conversion of high marsh habitat to low marsh, tidal flat or permanent inundation. Wetland expansion and resilience were not equally distributed through the estuary, with just three of 48 primary wetland areas encompassing >50% of projected new wetland by the year 2100. Our results open an avenue for improving predictive models of the response of freshwater tidal wetlands to sea level rise, and broadly inform the planning of conservation measures of this critical resource in the Hudson River Estuary.

  6. Sedimentary Records of Hyperpycnal Flows and the Influence of River Damming on Sediment Dynamics of Estuaries: Examples from the Nelson, Churchill, Moisie and Sainte-Marguerite Rivers (Canada)

    Science.gov (United States)

    St-Onge, G.; Duboc, Q.; Boyer-Villemaire, U.; Lajeunesse, P.; Bernatchez, P.

    2015-12-01

    Sediment cores were sampled in the estuary of the Nelson and Churchill Rivers in western Hudson Bay, as well as in the estuary of the Moisie and Sainte-Marguerite Rivers in Gulf of St. Lawrence in order to evaluate the impact of hydroelectric dams on the sedimentary regime of these estuaries. The gravity cores at the mouth of the Nelson River recorded several cm-thick rapidly deposited layers with a reverse to normal grading sequence, indicating the occurrence of hyperpycnal flows generated by major floods during the last few centuries. These hyperpycnal flows were probably caused by ice-jam formation, which can increase both the flow and the sediment concentration following the breaching of such natural dams. Following the construction of hydroelectric dams since the 1960s, the regulation of river discharge prevented the formation of hyperpycnal flows, and hence the deposition of hyperpycnites in the upper part of the cores. In the core sampled in the estuary of the Churchill River, only one hyperpycnite was recorded. This lower frequency may be due to the enclosed estuary of the Churchill River, its weaker discharge and the more distal location of the coring site.In the Gulf of St. Lawrence, grain size measurements allowed the identification of a major flood around AD 1844±4 years in box cores from both the Sainte-Marguerite and Moisie Rivers, whereas a drastic decrease in variations in the median grain size occurred around AD ~1900 in the estuary of the Sainte-Marguerite River, highlighting the offshore impact of the SM1 dam construction in the early 1900s. Furthermore, sedimentological variations in the box cores from both estuaries have been investigated by wavelet analysis and the sharp disappearance of high frequencies around AD 1900 in the estuary of the dammed river (Sainte-Marguerite River), but not in the estuary of the natural river (Moisie River), also provides evidence of the influence of dams on the sedimentary regime of estuaries.

  7. Birds of Mahi River estuary, Gujarat, India

    Directory of Open Access Journals (Sweden)

    P.J. Pandya

    2010-06-01

    Full Text Available The Mahi river estuary is one of the major estuaries of Gujarat. This paper presents a comprehensive list of birds of the Mahi river estuary (nearly 50 km stretch and the adjacent banks/ravines and defines the avian diversity at three major estuarine gradations with a brief check of similarity and diversity within the three. The present observation is the outcome of a 3 year period from August 2006 to July 2009. A sum total of 118 species belonging to 42 families were reported and listed as on Upstream, Midstream, and Downstream of estuary. No significant difference was seen in the species richness at the three zones; a change in avian composition at upstream and downstream was notable.

  8. What we didn't learn about the Hudson River, why, and what it means for environmental assessment

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Klauda, R.J.; Vaughan, D.S.

    1988-01-01

    Many of the major objectives of utility-sponsored and agency-sponsored Hudson River research programs were not achieved. Among these were identification and quantification of regulatory mechanisms and discovery of factors controlling year-class strength in striped bass and other important fish populations. Questions about community-level and ecosystem-level effects were not seriously addressed. Because of these limitations, an unambiguous assessment of the effects of power plants on the long-term production and persistence of Hudson River fish populations was not possible. It is argued that the failure to reach a scientifically defensible bottom line was largely due to: (1) institutional constraints on the design and conduct of assessment studies; (2) the complexity and spatiotemporal variability of estuarine ecosystems; and (3) the inadequacy of existing population and ecosystem theory. It is concluded that, for the foreseeable future, estimates of short-term impacts on populations will continue to be the most useful indices of power plants effects. Long-term monitoring and basic research on ecological processes in estuaries, funded and managed independently of the regulatory process, are essential to improving future environmental impact assessments. 44 refs

  9. Analysis of impingement impacts on Hudson River fish populations

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; van Winkle, W.

    1988-01-01

    Impacts of impingement, expressed as reductions in year-class abundance, were calculated for six Hudson River fish populations. Estimates were made for the 1974 and 1975 year classes of white perch, striped bass, Atlantic tomcod, and American shad, and the 1974 year classes of alewife and blueback herring. The maximum estimated reductions in year-class abundance were less than 5% for all year classes except the 1974 and 1975 white perch year classes and the 1974 striped bass year class. Only for white perch were the estimates greater than 10% per year. For striped bass, the 146,000 fish from the 1974 year class that were killed by impingement could have produced 12,000-16,000 5-year-old fish or 270-300 10-year-olds. Also estimated were the reductions in mortality that could have been achieved had closed-cycle cooling systems been installed at one or more of three power plants (Bowline point, Indian Point, and Roseton) and had the screen-wash systems at Bowline Point and Indian Point been modified to improve the survival of impinged fish. Closed-cycle cooling at all three plants would have reduced impingement impacts on white perch, striped bass, and Atlantic tomcod by 75% or more; installation of closed-cycle cooling at Indian Point alone would have reduced impingement impacts on white perch and Atlantic tomcod by 50%-80%. Modified traveling screens would have been less effective than closed-cycle cooling, but still would have reduced impingement impacts on white perch by roughly 20%. 23 refs., 1 fig., 3 tabs

  10. Estuary-wide genetic stock distribution and salmon habitat use, tidal-fluvial estuary - Columbia River Estuary Tidal Habitats

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of the tidal-fluvial estuary study is to determine the estuary's contribution to the spatial structure and life history diversity of Columbia River salmon...

  11. Mouth Bar Formation in Yangtze River Estuary

    NARCIS (Netherlands)

    Wei, C.

    2002-01-01

    The periodic shifting of the bifurcation point of the North Channel and South Channel of the Yangtze river is very important in the estuary. The North Channel is bifurcated from the South Branch by cutting a channel through the submerged sandbanks. Once a bifurcation channel is formed, the

  12. In-stream PIT detection, estuary wetlands - Columbia River Estuary Tidal Habitats

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of the tidal-fluvial estuary study is to determine the estuary's contribution to the spatial structure and life history diversity of Columbia River salmon...

  13. Salmon habitat use, tidal-fluvial estuary - Columbia River Estuary Tidal Habitats

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of the tidal-fluvial estuary study is to determine the estuary's contribution to the spatial structure and life history diversity of Columbia River salmon...

  14. Selective analysis of power plant operation on the Hudson River with emphasis on the Bowline Point Generating Station. Volume 2

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Cannon, J.B.; Christensen, S.G.

    1977-07-01

    Because of the location of the Bowline, Roseton, and Indian Point power generating facilities in the low-salinity zone of the Hudson estuary, operation of these plants with the present once-through cooling systems will adversely influence the fish populations that use the area for spawning and initial periods of growth and development. Recruitment rates and standing crops of several fish species may be lowered in response to the increased mortality caused by entrainment of nonscreenable eggs and larvae and by impingement of screenable young of the year. Entrainment and impingement data are particularly relevant for assessing which fish species have the greatest potential for being adversely affected by operation of Bowline, Roseton, and Indian Point with once-through cooling. These data from each of these three plants suggest that the six species that merit the greatest consideration are striped bass, white perch, tomcod, alewife, blueback herring, and bay anchovy. Two points of view are available for assessing the relative importance of the fish species in the Hudson River. From the fisheries point of view, the only two species of major importance are striped bass and shad. From the fish-community and ecosystem point of view, the dominant species, as determined by seasonal and regional standing crops (in numbers and biomass per hectare), are the six species most commonly entrained and impinged, namely, striped bass, white perch, tomcod, alewife, blueback herring, and anchovy

  15. Nutrient characterisation of river inflow into the estuaries of the ...

    African Journals Online (AJOL)

    Nutrient characterisation of river inflow into the estuaries of the Gouritz Water ... into the estuaries within the Gouritz Water Management Area (WMA) of South Africa. ... Long-term water quality monitoring data (dissolved inorganic nitrogen, i.e. ...

  16. Skagit IMW - Skagit River Estuary Intensively Monitored Watershed Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study evaluates system-level effects of several estuary restoration projects on juvenile Chinook salmon production in the Skagit River estuary. The monitoring...

  17. 33 CFR 207.60 - Federal Dam, Hudson River, Troy, N.Y.; pool level.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Federal Dam, Hudson River, Troy, N.Y.; pool level. 207.60 Section 207.60 Navigation and Navigable Waters CORPS OF ENGINEERS..., N.Y.; pool level. (a) Whenever the elevation of the pool created by the Federal dam at Troy, N.Y...

  18. 75 FR 39839 - Regulated Navigation Area; Hudson River and Port of NY/NJ

    Science.gov (United States)

    2010-07-13

    ... navigation area (RNA) from Port Coeymans, New York on the Hudson River to Jersey City, New Jersey on Upper... replacement span. DATES: This rule is effective from July 13, 2010 through October 31, 2010. The RNA will be... time and place announced by a later notice in the Federal Register. [[Page 39840

  19. Using destination image to predict visitors' intention to revisit three Hudson River Valley, New York, communities

    Science.gov (United States)

    Rudy M. Schuster; Laura Sullivan; Duarte Morais; Diane Kuehn

    2009-01-01

    This analysis explores the differences in Affective and Cognitive Destination Image among three Hudson River Valley (New York) tourism communities. Multiple regressions were used with six dimensions of visitors' images to predict future intention to revisit. Two of the three regression models were significant. The only significantly contributing independent...

  20. Low Latitude Pelagic Foraminifera Found in the Hudson River: Are They Hurricane Deposits?

    Science.gov (United States)

    Monahan, K. M.; Abbott, D. H.; Hoenisch, B.; Breger, D.

    2011-12-01

    River sediment cores provide a record of past environmental changes through stacked layers of sediments. In core CD02-29A, recovered from the southern Hudson River, a significant number of tropical planktic foraminifer tests were found. Foraminifera were concentrated in sediment layers of low impedance, suggesting high carbonate content. Because modern planktic foraminifera are exclusively marine, their presence in Hudson sediments in the core was remarkable. We can think of only two mechanisms that could explain this observation: either living specimens are carried upriver with the daily tides, or storm surges carry large amounts of seawater and re-suspended marine sediment upriver. To test for the presence of living specimens in Hudson River water, plankton tow samples were collected during high tide at the Hudson Battery south of the sample site, and at Piermont Pier north of the sample site and no living foraminifera were found. In addition, oxygen isotope (δ18O) analyses reveal a marine composition but the large difference in δ18O between the two surface dwelling species Globigerinoides ruber (pink) and Globigerinoides sacculifer, picked from the same sediment layer, suggests re-suspension and mixing of marine sediment deposits. Because only planktic, tropical to subtropical foraminiferal assemblages were found, the Hudson River deposits differ from previously recorded storm deposits found on Long Island and in New Jersey. In particular, the foraminiferal assemblages contain up to 40% G. ruber (pink), suggesting a highly tropical signal from a location where abundances of G. ruber are very low. This data, in addition to the pulsed occurrence of tests in the sediment suggests that the introduction of planktic foraminifera into the Hudson River must be driven by rare events. We suggest that storm surges from rare high-intensity hurricanes most likely explain the presence of these tests in Hudson River sediments, possibly assisted by the Gulf Stream entraining

  1. Hudson River Sub-Bottom Profile Lines_r09272010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Subbottom Profiler Tracklines. Data was collected November 5 to December 15, 2009, in the estuary north from Saugerties to Troy. Fugro utilized the GeoAcoustics...

  2. Side-Scan-Sonar Lines for Hudson River, NY

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Side Scan Sonar and Subbottom Profiler Tracklines. Data was collected November 5 to December 15, 2009, in the estuary north from Saugerties to Troy. Fugro utilized...

  3. Management of Fishery Resources in Yangtze River Estuary

    OpenAIRE

    Li, Meiling; Huang, Shuolin

    2009-01-01

    We introduce the fish fauna composition and main commercial fishes in Yangtze River estuary. We also analyze the current situation of resources and environment in Yangtze River estuary as well as the influential factors. Finally, related countermeasures are put forward on how to protect and use the fishery resources in Yangtze River.

  4. Peat Archives in the Hudson River Estuary… Marsh Formation, Carbon Storage and Release, and Resilience

    Science.gov (United States)

    Peteet, D. M.; Corbett, E. J.; Nichols, J. E.; Kenna, T. C.; Chang, C.

    2017-12-01

    We target deep peat stores (at least 8 meters) of carbon in the lower Hudson Estuary, which formed as the glacial fjord became an estuary with mid-Holocene sea level rise. These deep marshes play an extremely important role in the estuary health and stability in a changing climate. Never before have we faced the threats to coastal marshes that we are facing today, and the resulting sedimentation rates, inorganic/organic component histories, pollen, macrofossil, isotopic, and XRF data reveal critical information about past vegetation and climate change. Long-term shifts in organic/inorganic storage appear to be linked to drought, as watershed erosion results in more sand, silt and clay in the marshes. Climatic shifts often result in regional watershed shifts in vegetation, both locally and regionally. Understanding how these marshes are linked to human impact (disturbance, invasive species, higher nitrogen, heavy metal pollution, dams) over the last four centuries is critical to providing management of these key ecosystems, and their preservation as sea level rises. Quantification of processes that cause carbon degradation and release from these wetlands to the estuary is also key to this investigation. Peat loss would contribute to heavy metal pollution in the estuary as well as carbon loss. Young investigators from secondary schools in New York City participated in much of the fieldwork as part of the NASA/GISS NYC Research Initiative and the LDEO Secondary School Field Research Carbon Team.

  5. Radiogenic Lead Isotopes and Time Stratigraphy in the Hudson River, New York

    International Nuclear Information System (INIS)

    Chillrud, Steven N.; Bopp, Richard F.; Ross, James M.; Chaky, Damon A.; Hemming, Sidney; Shuster, Edward L.; Simpson, H. James; Estabrooks, Frank

    2004-01-01

    Radionuclide, radiogenic lead isotope and trace metal analyses on fine-grained sediment cores collected along 160 km of the upper and tidal Hudson River were used to examine temporal trends of contaminant loadings and to develop radiogenic lead isotopes both as a stratigraphic tool and as tracers for resolving decadal particle transport fluxes. Very large inputs of Cd, Sb, Pb, and Cr are evident in the sediment record, potentially from a single manufacturing facility. The total range in radiogenic lead isotope ratios observed in well-dated cores collected about 24 km downstream of the plant is large (e.g., maximum difference in 206 Pb/ 207 Pb is 10%), characterized by four major shifts occurring in the 1950s, 1960s, 1970s and 1980s. The upper Hudson signals in Cd and radiogenic lead isotopes were still evident in sediments collected 160 km downstream in the tidal Hudson. The large magnitude and abrupt shifts in radiogenic lead isotope ratios as a function of depth provide sensitive temporal constraints that complement information derived from radionuclide analyses to significantly improve the precision of dating assignments. Application of a simple dilution model to data from paired cores suggests much larger sediment inputs in one section of the river than previously reported, suggesting particle influxes to the Hudson have been underestimated

  6. Improving navigability on the Kromme River Estuary: A choice ...

    African Journals Online (AJOL)

    Navigation of estuaries is a vitally important aspect of boating recreation in South Africa and elsewhere. This paper uses a choice experiment to estimate recreation values of the Kromme River Estuary, a popular estuary along South Africa's east coast. This valuation methodology allows for the identification of preferred ...

  7. Methods to assess impacts on Hudson River white perch: report for the period October 1, 1978 to September 30, 1979

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Kirk, B.L.; Kumar, K.D.; Van Winkle, W.; Vaughan, D.S.

    1980-06-01

    This report is a brief description of the work done on the NRC project entitled 'Methods to Assess Impacts on Hudson River White Perch' October 1, 1978 to September 30, 1979. Accounts of special studies of white perch entrainment at Hudson River power plants, of density-dependent growth in the Hudson River white perch population, and of data on the white perch populations of the Delaware and Chesapeake systems were performed. Complete accounts of these special studies are included in this report. During this period, a final draft topical report entitled 'Evaluation of Impingement Losses of White Perch at the Indian Point Nuclear Station and Other Hudson River Power Plants' (NUREG/CR-1100) was completed

  8. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: M_MAMMAL (Marine Mammal Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine mammals (seals) in the Hudson River. Vector polygons in this data set represent marine mammal...

  9. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: ESI (Environmental Sensitivity Index Shoreline Types - Lines and Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector lines and polygons representing the shoreline and coastal habitats for the Hudson River, classified according to the Environmental...

  10. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: T_MAMMAL (Terrestrial Mammal Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for small terrestrial mammals (woodrats, myotis, muskrat, mink) for the Hudson River. Vector polygons in...

  11. Impact of entrainment and impingement on fish populations in the Hudson River estuary. Volume III. An analysis of the validity of the utilities' stock-recruitment curve-fitting exercise and prior estimation of beta technique. Environmental Sciences Division publication No. 1792

    International Nuclear Information System (INIS)

    Christensen, S.W.; Goodyear, C.P.; Kirk, B.L.

    1982-03-01

    This report addresses the validity of the utilities' use of the Ricker stock-recruitment model to extrapolate the combined entrainment-impingement losses of young fish to reductions in the equilibrium population size of adult fish. In our testimony, a methodology was developed and applied to address a single fundamental question: if the Ricker model really did apply to the Hudson River striped bass population, could the utilities' estimates, based on curve-fitting, of the parameter alpha (which controls the impact) be considered reliable. In addition, an analysis is included of the efficacy of an alternative means of estimating alpha, termed the technique of prior estimation of beta (used by the utilities in a report prepared for regulatory hearings on the Cornwall Pumped Storage Project). This validation methodology should also be useful in evaluating inferences drawn in the literature from fits of stock-recruitment models to data obtained from other fish stocks

  12. Historical changes in the Columbia River Estuary

    Science.gov (United States)

    Sherwood, Christopher R.; Jay, David A.; Bradford Harvey, R.; Hamilton, Peter; Simenstad, Charles A.

    Historical changes in the hydrology, sedimentology, and physical oceanography of the Columbia River Estuary have been evaluated with a combination of statistical, cartographic, and numerical-modelling techniques. Comparison of data digitized from US Coast and Geodetic Survey bathymetric surveys conducted in the periods 1867-1875, 1926-1937, and 1949-1958 reveals that large changes in the morphology of the estuary have been caused by navigational improvements (jetties, dredged channels, and pile dikes) and by the diking and filling of much of the wetland area. Lesser changes are attributable to natural shoaling and erosion. There has been roughly a 15% decrease in tidal prism and a net accumulation of about 68 × 10 6m 3 of sediment in the estuary. Large volumes of sediment have been eroded from the entrance region and deposited on the continental shelf and in the balance of the estuary, contributing to formation of new land. The bathymetric data indicate that, ignoring erosion at the entrance, 370 to 485 × 10 6m 3 of sediment has been deposited in the estuary since 1868 at an average rate of about 0.5 cm y -1, roughly 5 times the rate at which sea level has fallen locally since the turn of the century. Riverflow data indicate that the seasonal flow cycle of the Columbia River has been significantly altered by regulation and diversion of water for irrigation. The greatest changes have occurred in the last thirty years. Flow variability over periods greater than a month has been significantly damped and the net discharge has been slightly reduced. These changes in riverflow are too recent to be reflected in the available in the available bathymetric data. Results from a laterally averaged, multiple-channel, two-dimensional numerical flow model (described in HAMILTON, 1990) suggest that the changes in morphology and riverflow have reduced mixing, increased stratification, altered the response to fortnightly (neap-spring) changes in tidal forcing, and decreased the

  13. Influence of Aroclor 1242 Concentration on Polychlorinated Biphenyl Biotransformations in Hudson River Test Tube Microcosms

    Science.gov (United States)

    Fish, K. M.

    1996-01-01

    When 93.3 to 933 (mu)mol of Aroclor 1242 per kg was added to Hudson River sediment test tube microcosms, the rates of polychlorinated biphenyl biotransformations increased with increasing Aroclor 1242 concentration after a 4- to 8-week acclimation period. In contrast, when 37.3 (mu)mol of Aroclor 1242 per kg was added, polychlorinated biphenyl biotransformations occurred at slow constant rates. PMID:16535387

  14. Distributions of polyhalogenated compounds in Hudson River (New York, USA) fish in relation to human uses along the river

    International Nuclear Information System (INIS)

    Skinner, Lawrence C.

    2011-01-01

    PCBs (as Aroclor concentrations) have been extensively examined in fish along the Hudson River, but other xenobiotic chemicals in fish have had limited assessment. This study determined concentrations and congener distributions of polybrominated diphenyl ethers (PBDEs), polybrominated and polychlorinated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs and PCDD/Fs), and polychlorinated biphenyls (PCBs) in smallmouth bass and striped bass taken from a 385 km reach of the Hudson River. Concentrations of PBDEs and PCBs in smallmouth bass, and PCBs in striped bass, were positively related to human uses of the compounds in the basin. Generally low levels of PCDD/Fs were found. One striped bass, however, contained elevated 2,3,7,8-TCDD, indicating exposure to a known source in the adjacent Newark Bay-Passaic River basin. PBDDs were generally below detection. PBDFs were present in four of 18 smallmouth bass, but were not detected in striped bass. Dioxin-like PCBs contribute most to 2,3,7,8-TCDD toxic equivalents in 29 of 30 samples. - Highlights: → In the Hudson River, → PBDEs in smallmouth bass follow human population patterns, but do not for striped bass. → Proximity to known PCB sources govern PCB levels and patterns in fish. → PBDFs were in smallmouth bass but not striped bass. PBDDs were present in one fish. → PCDD/Fs were low in 29 of 30 fish. A 2,3,7,8-TCDD source affected one striped bass. → PCBs contribute most to 2,3,7,8-TCDD toxic equivalents in 29 of 30 samples. - Residues of polyhalogenated compounds in resident and migratory fish from the Hudson River are compared with human uses of the compounds in the river basin.

  15. Distributions of polyhalogenated compounds in Hudson River (New York, USA) fish in relation to human uses along the river

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Lawrence C., E-mail: lxskinne@gw.dec.state.ny.us [New York State Department of Environmental Conservation, 625 Broadway, Albany, NY 12233 (United States)

    2011-10-15

    PCBs (as Aroclor concentrations) have been extensively examined in fish along the Hudson River, but other xenobiotic chemicals in fish have had limited assessment. This study determined concentrations and congener distributions of polybrominated diphenyl ethers (PBDEs), polybrominated and polychlorinated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs and PCDD/Fs), and polychlorinated biphenyls (PCBs) in smallmouth bass and striped bass taken from a 385 km reach of the Hudson River. Concentrations of PBDEs and PCBs in smallmouth bass, and PCBs in striped bass, were positively related to human uses of the compounds in the basin. Generally low levels of PCDD/Fs were found. One striped bass, however, contained elevated 2,3,7,8-TCDD, indicating exposure to a known source in the adjacent Newark Bay-Passaic River basin. PBDDs were generally below detection. PBDFs were present in four of 18 smallmouth bass, but were not detected in striped bass. Dioxin-like PCBs contribute most to 2,3,7,8-TCDD toxic equivalents in 29 of 30 samples. - Highlights: > In the Hudson River, > PBDEs in smallmouth bass follow human population patterns, but do not for striped bass. > Proximity to known PCB sources govern PCB levels and patterns in fish. > PBDFs were in smallmouth bass but not striped bass. PBDDs were present in one fish. > PCDD/Fs were low in 29 of 30 fish. A 2,3,7,8-TCDD source affected one striped bass. > PCBs contribute most to 2,3,7,8-TCDD toxic equivalents in 29 of 30 samples. - Residues of polyhalogenated compounds in resident and migratory fish from the Hudson River are compared with human uses of the compounds in the river basin.

  16. Tritium in the Savannah River Estuary and adjacent marine waters

    International Nuclear Information System (INIS)

    Hayes, D.W.

    1978-01-01

    The tritium distribution in the Savannah River estuary and adjacent marine waters was measured to provide information on the dilution, mixing, and movement of Savannah River water in this region. The Savannah River marine region was chosen because the average tritium concentration in this river is 5 pCi/ml, whereas other rivers in the southeastern United States average less than 0.5 pCi/ml. The increased tritium concentration in the Savannah River is due to releases from the Savannah River Plant of the Department of Energy. Tritium measurements have proved particularly effective in estimating the flushing time of the Savannah River estuary (2.4 days) and in delineating the relative contribution to the water masses in Ossabaw and Port Royal Sounds from the River and from sea water. Ossabaw and Port Royal Sounds are located approximately 20 km south and north of the Savannah River estuary, respectively

  17. Tritium in the Savannah River estuary and adjacent marine waters

    International Nuclear Information System (INIS)

    Hayes, D.W.

    1979-01-01

    The tritium distribution in the Savannah River estuary and adjacent marine waters was measured to provide information on the dilution, mixing and movement of Savannah River water in this region. The Savannah River marine region was chosen because the average tritium concentration in this river is approximately 5 pCi/ml, whereas other rivers in the southeastern United States of America average less than 0.5 pCi/ml. The increased tritium concentration in the Savannah River is due to releases from the Savannah River Plant of the Department of Energy. Tritium measurements have proved particularly effective in estimating the flushing time of the Savannah River estuary (2.4 days) and in delineating the relative contribution to the water masses in Ossabaw and Port Royal Sounds from the river and from sea-water. Ossabaw and Port Royal Sounds are located approximately 20 km south and north of the Savannah River estuary respectively. (author)

  18. Hudson River Unionids and Zebra Mussels: The Beginning of the End or the End of the Beginning?

    Science.gov (United States)

    Strayer, D. L.; Malcom, H. M.

    2005-05-01

    The invasion of the Hudson River estuary by zebra mussels was followed by steep declines (77 to >99.7%) in populations of all species of native bivalves between 1992 and 1999. Body condition of all unionids, and growth and recruitment of young unionids also declined significantly. Declines in population size and body condition were correlated primarily with the filtration rate of the zebra mussel population, not with fouling of native bivalves by zebra mussels. Samples taken since 2000, however, have shown that populations of all 4 common native bivalves have stabilized or even recovered, although the zebra mussel population has not declined. The mechanisms underlying this apparent reversal of fortune are not clear: recruitment and growth of young mussels have showed limited recovery, but body condition of adults has not. We found no evidence that spatial refuges contributed to this reversal of population declines. Simple statistical models project now that native bivalves may persist at population densities about an order of magnitude below their pre-invasion densities.

  19. 76 FR 8345 - Endangered and Threatened Species; Recovery Plan Module for Columbia River Estuary Salmon and...

    Science.gov (United States)

    2011-02-14

    ... and Threatened Species; Recovery Plan Module for Columbia River Estuary Salmon and Steelhead AGENCY.... ACTION: Notice of availability; recovery plan module for Columbia River estuary salmon and steelhead... Plan Module for Salmon and Steelhead (Estuary Module). The Estuary Module addresses the estuary...

  20. Estuary fish data - Juvenile salmon in migratory corridors of lower Columbia River estuary

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sampling juvenile salmon and associated fishes in open waters of the lower Columbia River estuary. Field work includes bi-weekly sampling during the spring...

  1. Understanding Spatial and Temporal Shifts in Blue Carbon, Piermont Marsh, Lower Hudson Estuary, NY

    Science.gov (United States)

    Peteet, D. M.; Nichols, J. E.; Kenna, T. C.; Corbett, E. J.; Allen, K. A.; Newton, R.; Vincent, S.; Haroon, A.; Shumer, M.

    2015-12-01

    Piermont Marsh is a National Estuarine Research Reserve (NERR) protected brackish wetland in the lower Hudson Valley. It serves as a nursery for fish, a coastal buffer in storms, a repository of native wetland species unique to the Hudson, and a paleoenvironmental archive. At risk for disappearance due to rising sea level, we assess the present carbon stores and their spatial and temporal variability through time. Determining the depth of peat in transects throughout Piermont Marsh (41°N, 73°55'W), is one step in reconstructing the stores of carbon in the marsh and how they have shifted over millennia. Through the last decade, we have focused field efforts on probing the depths of the marsh through a series of transects and in acquiring sediment cores from which we establish sedimentation rates and carbon storage through time. AMS C-14 dating, XRF fluorescence, pollen analysis, and Cesium-137 provide chronological control for the sedimentation rates, pollution history, and an understanding of the regional and local shifts in vegetation. C-13 and pollen measurements in selected cores indicate major shifts in local vegetation with coastal eutrophication as the marsh has been invaded, first by Typha angustifolia in the nineteenth century and then by Phragmites australis in the twentieth century up to the present. N-15 measurements indicate a large shift in nitrogen as humans have impacted the marsh. We present a comprehensive, three-dimensional view of the effects of climate, vegetation, and human impact on the carbon storage of Piermont Marsh. This project provided a site for a place- and project-based learning through Lamont-Doherty's Secondary School Field Research Program. Many of the field samples were collected by young investigators from schools in New York City and towns near Piermont.

  2. Measurement Error Affects Risk Estimates for Recruitment to the Hudson River Stock of Striped Bass

    Directory of Open Access Journals (Sweden)

    Dennis J. Dunning

    2002-01-01

    Full Text Available We examined the consequences of ignoring the distinction between measurement error and natural variability in an assessment of risk to the Hudson River stock of striped bass posed by entrainment at the Bowline Point, Indian Point, and Roseton power plants. Risk was defined as the probability that recruitment of age-1+ striped bass would decline by 80% or more, relative to the equilibrium value, at least once during the time periods examined (1, 5, 10, and 15 years. Measurement error, estimated using two abundance indices from independent beach seine surveys conducted on the Hudson River, accounted for 50% of the variability in one index and 56% of the variability in the other. If a measurement error of 50% was ignored and all of the variability in abundance was attributed to natural causes, the risk that recruitment of age-1+ striped bass would decline by 80% or more after 15 years was 0.308 at the current level of entrainment mortality (11%. However, the risk decreased almost tenfold (0.032 if a measurement error of 50% was considered. The change in risk attributable to decreasing the entrainment mortality rate from 11 to 0% was very small (0.009 and similar in magnitude to the change in risk associated with an action proposed in Amendment #5 to the Interstate Fishery Management Plan for Atlantic striped bass (0.006— an increase in the instantaneous fishing mortality rate from 0.33 to 0.4. The proposed increase in fishing mortality was not considered an adverse environmental impact, which suggests that potentially costly efforts to reduce entrainment mortality on the Hudson River stock of striped bass are not warranted.

  3. Potential well yields from unconsolidated deposits in the lower Hudson and Delaware River basins, New York

    Science.gov (United States)

    Wolcott, Stephen W.

    1987-01-01

    A comprehensive groundwater protection plan, developed by the New York State Department of Environmental Conservation in 1985, identified the need to delineate significant aquifers within the state. A map of the unconsolidated aquifers in the lower Hudson and Delaware River basins was compiled from available data on the surficial geology and well yields. It delineates the significant unconsolidated aquifers and indicates the potential yield of wells that tap these aquifers. The potential well yield is categorized into three ranges: 100 gal/min. No yield range is given for till, but some large diameter or dug wells in till may yield up 10 gal/min. (Lantz-PTT)

  4. St. Louis River Estuary 2011 - 2013 Faucet snail location data

    Data.gov (United States)

    U.S. Environmental Protection Agency — The dataset consists of GPS coordinates for benthic invertebrate collections made in the St. Louis River Estuary in 2011 through 2013, and information on whether and...

  5. Short term variations in particulate matter in Mahi river estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Rokade, M.A.; Zingde, M.D.

    The particulate matter (PM) collected from Mahi River Estuary was analysed for organic carbon (POC), nitrogen (PON), and chlorophyll a (Chl a). The concentration of PM, POC, PON and Chl a showed short term variations. Average surface concentration...

  6. Phytoplankton Diversity in the Cross River Estuary of Nigeria ...

    African Journals Online (AJOL)

    DR. MIKE HORSFALL

    This study was carried out to provide a concise set of structural based .... further growth of diatom in this zone due to rapid uptake of ... Table 1: Taxonomic listing and spatial distribution of phytoplankton species in Cross Rivers estuary. (+ =.

  7. Impact of impingement on the Hudson River white perch population. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Barnthouse, L.W.; Van Winkle, W.; Kirk, B.L.; Vaughan, D.S.

    1982-02-01

    This report summarizes a series of analyses of the magnitude and biological significance of the impingement of white perch at the Indian Point Nuclear Generating Station and other Hudson River power plants. Included in these analyses were evaluations of: (1) two independent lines of evidence relating to the magnitude of impingement impacts on the Hudson River white perch population; (2) the additional impact caused by entrainment of white perch; (3) data relating to density-dependent growth among young-of-the-year white perch; (4) the feasibility of performing population-level analyses of impingement impacts on the white perch populations of Chesapeake Bay and the Delaware River; and (5) the feasibility of using simple food chain and food web models to evaluate community-level effects of impingement and entrainment. Estimated reductions in the abundances of the 1974 and 1975 white perch year classes, caused by impingement and entrainment, were high enough that the possibility of adverse long-term effects cannot be excluded.

  8. Methods to assess impacts on Hudson River striped bass: report for the period October 1, 1977 to September 30, 1979

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Christensen, S.W.; Kirk, B.L.; Kumar, K.D.; Van Winkle, W.

    1980-06-01

    The overall objective of this project is to develop and apply quantitative methods for assessing the effects of power plant entrainment and impingement on the Hudson River striped bass population. During the two years covered in this reporting period, our work dealt with five interrelated aspects of this assessment problem: (1) young-of-the year models, (2) mortality of entrained eggs, larvae, and juveniles, (3) projection of long-term impacts using stock recruitment models, (4) relative contribution of the Hudson River stock to the Atlantic coastal striped bass population, and (5) distribution of entrainable striped bass life stages in the immediate vicinity of power plant intakes

  9. Juvenile salmon usage of the Skeena River estuary.

    Science.gov (United States)

    Carr-Harris, Charmaine; Gottesfeld, Allen S; Moore, Jonathan W

    2015-01-01

    Migratory salmon transit estuary habitats on their way out to the ocean but this phase of their life cycle is more poorly understood than other phases. The estuaries of large river systems in particular may support many populations and several species of salmon that originate from throughout the upstream river. The Skeena River of British Columbia, Canada, is a large river system with high salmon population- and species-level diversity. The estuary of the Skeena River is under pressure from industrial development, with two gas liquefaction terminals and a potash loading facility in various stages of environmental review processes, providing motivation for understanding the usage of the estuary by juvenile salmon. We conducted a juvenile salmonid sampling program throughout the Skeena River estuary in 2007 and 2013 to investigate the spatial and temporal distribution of different species and populations of salmon. We captured six species of juvenile anadromous salmonids throughout the estuary in both years, and found that areas proposed for development support some of the highest abundances of some species of salmon. Specifically, the highest abundances of sockeye (both years), Chinook in 2007, and coho salmon in 2013 were captured in areas proposed for development. For example, juvenile sockeye salmon were 2-8 times more abundant in the proposed development areas. Genetic stock assignment demonstrated that the Chinook salmon and most of the sockeye salmon that were captured originated from throughout the Skeena watershed, while some sockeye salmon came from the Nass, Stikine, Southeast Alaska, and coastal systems on the northern and central coasts of British Columbia. These fish support extensive commercial, recreational, and First Nations fisheries throughout the Skeena River and beyond. Our results demonstrate that estuary habitats integrate species and population diversity of salmon, and that if proposed development negatively affects the salmon populations that

  10. Nutrient input through submarine groundwater discharge in two major Chinese estuaries: the Pearl River Estuary and the Changjiang River Estuary

    Science.gov (United States)

    Liu, Jianan; Du, Jinzhou; Wu, Ying; Liu, Sumei

    2018-04-01

    In this study, we used a 224Ra mass balance model to evaluate the importance of submarine groundwater discharge (SGD) for the budgets of biogenic elements in two major Chinese estuaries: the Pearl River Estuary (PRE) and the Changjiang River Estuary (CRE). The apparent water age in the PRE was estimated to be 4.8 ± 1.1 days in the dry season and 1.8 ± 0.6 days in the wet season using a physical model based on the tidal prism. In the dry season, the water age in the CRE was estimated to be 11.7 ± 3.0 days using the 224Ra/223Ra activities ratios apparent age model. By applying the 224Ra mass balance model, we obtained calculations of the SGD flow in the PRE of (4.5-10) × 108 m3 d-1 (0.23-0.50 m3 m-2 d-1) and (1.2-2.7) × 108 m3 d-1 (0.06-0.14 m3 m-2 d-1) in the dry season and wet season, respectively, and the estimated SGD flux was (4.6-11) × 109 m3 d-1 (0.18-0.45 m3 m-2 d-1) in the dry season of the CRE. In comparison with the nutrient fluxes from the rivers, the SGD-derived nutrient fluxes may play a vital role in controlling the nutrient budgets and stoichiometry in the study areas. The large amount of dissolved inorganic nitrogen and phosphorus fluxes together with high N: P ratios into the PRE and CRE would potentially contribute to eutrophication and the occurrence of red tides along the adjacent waters.

  11. Groundwater quality in the Upper Hudson River Basin, New York, 2012

    Science.gov (United States)

    Scott, Tia-Marie; Nystrom, Elizabeth A.

    2014-01-01

    Water samples were collected from 20 production and domestic wells in the Upper Hudson River Basin (north of the Federal Dam at Troy, New York) in New York in August 2012 to characterize groundwater quality in the basin. The samples were collected and processed using standard U.S. Geological Survey procedures and were analyzed for 148 physiochemical properties and constituents, including dissolved gases, major ions, nutrients, trace elements, pesticides, volatile organic compounds (VOCs), radionuclides, and indicator bacteria. The Upper Hudson River Basin covers 4,600 square miles in upstate New York, Vermont, and Massachusetts; the study area encompasses the 4,000 square miles that lie within New York. The basin is underlain by crystalline and sedimentary bedrock, including gneiss, shale, and slate; some sandstone and carbonate rocks are present locally. The bedrock in some areas is overlain by surficial deposits of saturated sand and gravel. Eleven of the wells sampled in the Upper Hudson River Basin are completed in sand and gravel deposits, and nine are completed in bedrock. Groundwater in the Upper Hudson River Basin was typically neutral or slightly basic; the water typically was moderately hard. Bicarbonate, chloride, calcium, and sodium were the major ions with the greatest median concentrations; the dominant nutrient was nitrate. Methane was detected in 7 samples. Strontium, iron, barium, boron, and manganese were the trace elements with the highest median concentrations. Two pesticides, an herbicide degradate and an insecticide degredate, were detected in two samples at trace levels; seven VOCs, including chloroform, four solvents, and the gasoline additive methyl tert-butyl ether (MTBE) were detected in four samples. The greatest radon-222 activity, 2,900 picocuries per liter, was measured in a sample from a bedrock well; the median radon activity was higher in samples from bedrock wells than in samples from sand and gravel wells. Coliform bacteria were

  12. Declining metal levels at Foundry Cove (Hudson River, New York): Response to localized dredging of contaminated sediments

    International Nuclear Information System (INIS)

    Mackie, Joshua A.; Natali, Susan M.; Levinton, Jeffrey S.; Sanudo-Wilhelmy, Sergio A.

    2007-01-01

    This study examines the effectiveness of remediating a well-recognized case of heavy metal pollution at Foundry Cove (FC), Hudson River, New York. This tidal freshwater marsh was polluted with battery-factory wastes (1953-1979) and dredged in 1994-1995. Eight years after remediation, dissolved and particulate metals (Cd, Co, Cu, Pb, Ni, and Ag) were found to be lower than levels in the lower Hudson near New York City. Levels of metals (Co, Ni, Cd) on suspended particles were comparatively high. Concentrations of surface sediment Cd throughout the marsh system remain high, but have decreased both in the dredged and undredged areas: Cd was 2.4-230 mg/kg dw of sediment in 2005 vs. 109-1500 mg/kg in the same area in 1983. The rate of tidal export of Cd from FC has decreased by >300-fold, suggesting that dredging successfully stemmed a major source of Cd to the Hudson River. - Dredging of a hotspot of metal-contaminated sediment is associated with a recognizable local and river-wide decline in cadmium in the Hudson River, New York

  13. The Natural Palette: Hudson River Artists and the Land. Teacher's Guide. Curriculum Resource: Grades 4 through 12.

    Science.gov (United States)

    Lind, Ted; Sorin, Gretchen Sullivan; Mack, Stevie; Fiore, Jennifer, Ed.

    This interdisciplinary curriculum guide resource kit focuses on 19th-century Euro-American painters of the Hudson River School. Lessons are designed to encourage student recognition of the significant impact of North American Indians, the natural environment, and the romantic period writers and philosophers artists and their work. The guide…

  14. Computer simulation model for the striped bass young-of-the-year population in the Hudson River

    International Nuclear Information System (INIS)

    Eraslan, A.H.; Van Winkle, W.; Sharp, R.D.; Christensen, S.W.; Goodyear, C.P.; Rush, R.M.; Fulkerson, W.

    1975-09-01

    This report presents a daily transient (tidal-averaged), longitudinally one-dimensional (cross-section-averaged) computer simulation model for the assessment of the entrainment and impingement impacts of power plant operations on young-of-the-year populations of the striped bass, Morone saxatilis, in the Hudson River

  15. Riverbed Micromorphology of the Yangtze River Estuary, China

    Directory of Open Access Journals (Sweden)

    Shuaihu Wu

    2016-05-01

    Full Text Available Dunes are present in nearly all fluvial channels and are vital in understanding sediment transport, deposition, and flow conditions during floods of rivers and estuaries. This information is pertinent for helping developing management practices to reduce risks in river transportation and engineering. Although a few recent studies have investigated the micromorphology of a portion of the Yangtze River estuary in China, our understanding of dune development in this large estuary is incomplete. It is also poorly understood how the development and characteristics of these dunes have been associated with human activities in the upper reach of the Yangtze River and two large-scale engineering projects in the estuarine zone. This study analyzed the feature in micromorphology of the entire Yangtze River estuary bed over the past three years and assessed the morphological response of the dunes to recent human activities. In 2012, 2014, and 2015, multi-beam bathymetric measurements were conducted on the channel surface of the Yangtze River estuary. The images were analyzed to characterize the subaqueous dunes and detect their changes over time. Bottom sediment samples were collected for grain size analysis to assess the physical properties of the dunes. We found that dunes in the Yangtze River estuary can be classified in four major classes: very large dunes, large dunes, medium dunes, and small dunes. Large dunes were predominant, amounting to 51.5%. There was a large area of dunes developed in the middle and upper reaches of the Yangtze River estuary and in the Hengsha Passage. A small area of dunes was observed for the first time in the turbidity maximum zone of the Yangtze River estuary. These dunes varied from 0.12 to 3.12 m in height with a wide range of wavelength from 2.83 to 127.89 m, yielding a range in height to wavelength of 0.003–0.136. Sharp leeside slope angles suggest that the steep slopes of asymmetrical dunes in the middle and upper

  16. 77 FR 40518 - Swim Events in the Captain of the Port New York Zone; Hudson River, East River, Upper New York...

    Science.gov (United States)

    2012-07-10

    ... 1625-AA00 Swim Events in the Captain of the Port New York Zone; Hudson River, East River, Upper New York Bay, Lower New York Bay; New York, NY ACTION: Final rule. SUMMARY: The Coast Guard is establishing seven temporary safety zones for swim events within the Captain of the Port (COTP) New York Zone. These...

  17. Trace elements and radionuclides in the Connecticut River and Amazon River estuary

    International Nuclear Information System (INIS)

    Dion, E.P.

    1983-01-01

    The Connecticut River, its estuary, and the Amazon River estuary were studied to elucidate some of the processes which control river water chemistry and the flux of elements to the sea. The approach taken was to identify inputs to the Connecticut River and to investigate geochemical processes which modify the dissolved load. The form and quantity of nuclides which are in turn supplied to the estuary are altered by processes unique to that transition zone to the ocean. The Connecticut River estuary was sampled on a seasonal basis to investigate the role of the estuary in controlling the flux of elements to the sea. The knowledge gained from the Connecticut River study was applied to the quantitatively more significant Amazon River estuary. There a variety of samples were analyzed to understand the processes controlling the single greatest flux of elements to the Atlantic Ocean. The results indicate that estimates of the total flux of nuclides to the oceans can best be calculated based on groundwater inputs. Unless significant repositories for nuclides exist in the river-estuarine system, the groundwater flux of dissolved nuclides is that which will eventually be delivered to the ocean despite the reactions which were shown to occur in both rivers and estuaries. 153 references, 63 figures, 28 tables

  18. Survival of fishes after impingement on traveling screens at Hudson River power plants

    International Nuclear Information System (INIS)

    Muessig, P.H.; Hutchison, J.B.; King, L.R.; Ligotino, R.J.; Daley, M.

    1988-01-01

    The survival of Hudson River fishes, juveniles and adults, after they had been impinged on continuously rotated traveling screens at the Bowline Point and Danskammer Point power plants was examined. Survival of principal species was similar at the two plants, and estimates of survival improved as monitoring stress was reduced. Adjusted for survival of control fish, survival over 84-108 h after fish were recovered from the screens was highest for Atlantic tomcod, striped bass, and white perch (50-90%) and lowest for bay anchovy, alewife, and blueback herring; other species showed intermediate survival. Survival of striped bass and white perch was positively correlated with water temperature in winter and with conductivity in spring and fall. Continual rotation of the screens, which shortens the average time that fish are impinged, increased survival over that associated with intermittent rotation. 24 refs., 9 figs., 4 tabs

  19. Continuous resistivity profiling data from the Corsica River Estuary, Maryland

    Science.gov (United States)

    Cross, V.A.; Bratton, J.F.; Worley, C.R.; Crusius, J.; Kroeger, K.D.

    2011-01-01

    Submarine groundwater discharge (SGD) into Maryland's Corsica River Estuary was investigated as part of a larger study to determine its importance in nutrient delivery to the Chesapeake Bay. The Corsica River Estuary represents a coastal lowland setting typical of much of the eastern bay. An interdisciplinary U.S. Geological Survey (USGS) science team conducted field operations in the lower estuary in April and May 2007. Resource managers are concerned about nutrients that are entering the estuary via SGD that may be contributing to eutrophication, harmful algal blooms, and fish kills. Techniques employed in the study included continuous resistivity profiling (CRP), piezometer sampling of submarine groundwater, and collection of a time series of radon tracer activity in surface water. A CRP system measures electrical resistivity of saturated subestuarine sediments to distinguish those bearing fresh water (high resistivity) from those with saline or brackish pore water (low resistivity). This report describes the collection and processing of CRP data and summarizes the results. Based on a grid of 67.6 kilometers of CRP data, low-salinity (high-resistivity) groundwater extended approximately 50-400 meters offshore from estuary shorelines at depths of 5 to >12 meters below the sediment surface, likely beneath a confining unit. A band of low-resistivity sediment detected along the axis of the estuary indicated the presence of a filled paleochannel containing brackish groundwater. The meandering paleochannel likely incised through the confining unit during periods of lower sea level, allowing the low-salinity groundwater plumes originating from land to mix with brackish subestuarine groundwater along the channel margins and to discharge. A better understanding of the spatial variability and geological controls of submarine groundwater flow beneath the Corsica River Estuary could lead to improved models and mitigation strategies for nutrient over-enrichment in the

  20. The importance of the river-estuary interface (REI) zone in estuaries

    African Journals Online (AJOL)

    drinie

    2002-07-03

    Jul 3, 2002 ... A multidisciplinary and multi-institutional research programme studied the influence of river flow rate on salinity distribution and response of the ... alia, the state of the mouth influences the extent of water exchange with the sea, vertical and ... The Kariega Estuary is a marine dominated system with very little.

  1. Selective analysis of power plant operation on the Hudson River with emphasis on the Bowline Point Generating Station. Volume 1

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Cannon, J.B.; Christensen, S.G.

    1977-07-01

    A comprehensive study of the effects of power plant operation on the Hudson River was conducted. The study included thermal, biological, and air quality effects of existing and planned electrical generating stations. This section on thermal impacts presents a comprehensive mathematical modeling and computer simulation study of the effects of heat rejection from the plants. The overall study consisted of three major parts: near-field analysis; far-field analysis; and zone-matched near-field/far-field analysis. Near-field analyses were completed for Roseton, Danskammer, and Bowline Point Generating Stations, and near-field dilution ratios range from a low of about 2 for Bowline Point and 3 for Roseton to a maximum of 6 for both plants. The far-field analysis included a critical review of existing studies and a parametric review of operating plants. The maximum thermal load case, based on hypothetical 1974 river conditions, gives the daily maximum cross-section-averaged and 2-mile-segment-averaged water temperatures as 83.80 0 F in the vicinity of the Indian Point Station and 83.25 0 F in the vicinity of the Bowline Station. This maximum case will be significantly modified if cooling towers are used at certain units. A full analysis and discussion of these cases is presented. A study of the Hudson River striped bass population is divided into the following eight subsections: distribution of striped bass eggs, larvae, and juveniles in the Hudson River; entrainment mortality factor; intake factor; impingement; effects of discharges; compensation; model estimates of percent reduction; and Hudson River striped bass stock

  2. Physical biological coupling in the Pearl River Estuary

    Science.gov (United States)

    Harrison, Paul J.; Yin, Kedong; Lee, J. H. W.; Gan, Jianping; Liu, Hongbin

    2008-07-01

    The Pearl River Estuary is a subtropical estuary and the second largest in China based on discharge volume from the Pearl River. Processes in the estuary vary spatially and temporally (wet vs dry season). In the dry season at the head of the estuary, hypoxic and nearly anoxic conditions occur and NH 4 reaches >600 μM, NO 3 is ˜300 μM and nitrite is ˜60 μM indicating that nitrification and denitrification may be important dry season processes in the region extending 40 km upstream of the Humen outlet. There are very few biological studies conducted in this upper section of the estuary in either the dry or wet seasons and hence there is a need for further research in this region of the river. In the wet season, the salinity wedge extends to the Hongqimen outlet and oxygen is low (35-80% saturation). Nitrate is ˜100 μM, silicate ˜140 μM; and phosphate is relatively low at ˜0.5 μM, yielding an N:P ratio up to ˜200:1 in summer. Nutrients decrease in the lower estuary and primary productivity may become potentially P-limited. Eutrophication is not as severe as one would expect from the nutrient inputs from the Pearl River and from Hong Kong's sewage discharge. This estuary shows a remarkable capacity to cope with excessive nutrients. Physical processes such as river discharge, tidal flushing, turbulent dispersion, wind-induced mixing, and estuarine circulation play an important role in controlling the production and accumulation of algal blooms and the potential occurrence of hypoxia. Superimposed on the physical processes of the estuary are the chemical and biological processes involved in the production of the bloom. For example, the 100N:1P ratio indicates that P potentially limits the amount of algal biomass (and potential biological oxygen demand) in summer. While extended periods of hypoxia are rare in Hong Kong waters, episodic events have been reported to occur during late summer due to factors such as low wind, high rainfall and river discharge which

  3. Hydrographic and chemical observations in the Sierra Leone River estuary

    International Nuclear Information System (INIS)

    Koske, P.H.; Weiler, K.

    1979-01-01

    Hydrographic and chemical observations in the Sierra Leone River estuary are reported, a West-African river in the tropics. Because of the typical change between rainy season in the sommer months and dry season in winter time the research work has been adapted to these semi-annual changes. The collected data and results are given and discussed under this aspect of the seasonal fluctuations. (orig.) [de

  4. Trace elements distribution in bottom sediments from Amazon River estuary

    International Nuclear Information System (INIS)

    Lara, L.B.L.S.; Nadai Fernandes, E. de; Oliveira, H. de; Bacchi, M.A.

    1994-01-01

    The Amazon River discharges into a dynamic marine environment where there have been many interactive processes affecting dissolved and particulate solids, either those settling on the shelf or reaching the ocean. Trace elemental concentration, especially of the rare earth elements, have been determined by neutron activation analysis in sixty bottom sediment samples of the Amazon River estuary, providing information for the spatial and temporal variation study of those elements. (author). 16 refs, 6 figs, 3 tabs

  5. 76 FR 23306 - Takes of Marine Mammals Incidental to Specified Activities; Russian River Estuary Management...

    Science.gov (United States)

    2011-04-26

    ... Marine Mammals Incidental to Specified Activities; Russian River Estuary Management Activities AGENCY...) to incidentally harass, by Level B harassment only, three species of marine mammals during estuary... December 31, 2010; and Russian River Estuary Outlet Channel Adaptive Management Plan. NMFS' Environmental...

  6. Flushing characteristics of Mahim river estuary (Bombay)

    Digital Repository Service at National Institute of Oceanography (India)

    Sabnis, M.M; Zingde, M

    to the influence of wastewater. Flushing time of 19 tidal cycles was estimated by applying modified tidal prism method. After a large number of tidal cycles the estuary would retain 9.3x10 super(4) m super(3) of wastewater which was over 15% of the spring high tide...

  7. Hydrodynamics of the Bot river estuary revisited

    CSIR Research Space (South Africa)

    Van Niekerk, L

    2005-01-01

    Full Text Available For the past 20 years management of the Bot/Kleinmond estuarine system in the south-western Cape has been based on the premise that, barring intervention, the estuary was naturally evolving into a freshwater coastal lake. This paper presents...

  8. Sedimentation in a river dominated estuary

    CSIR Research Space (South Africa)

    Cooper, JAG

    1993-10-01

    Full Text Available The Mgeni Estuary on the wave dominated cast coast of South Africa occupies a narrow, bedrock confined, alluvial valley and is partially blocked at the coast by an elongate sandy barrier. Fluvial sediment extends to the barrier and marine depositon...

  9. Replication of Annual Cycles in Mn in Hudson River Cores: Mn Peaks During High Water Flow

    Science.gov (United States)

    Abbott, D. H.; Hutson, D.; Marrero, A. M.; Block, K. A.; Chang, C.; Cai, Y.

    2017-12-01

    Using the results from an ITRAX, XRF scanner, we previously reported apparent annual cycles in Mn in a single, high sedimentation rate Hudson River core, LWB1-8, taken off Yonkers, NY (Carlson et al., 2016). We replicated these results in three more high sedimentation rate cores and found stratigraphic markers that verify our inferences about the annual nature of the Mn cycles. The three new cores are LWB4-5 taken off Peekskill, NY, and LWB3-44 and LWB3-25, both taken in Haverstraw Bay. The cores are from water depths of 7-9 meters and all have high magnetic susceptibilities (typically > 30 cgs units) in their upper 1 to 2 meters. The high susceptibilities are primarily produced by magnetite from modern industrial combustion. One core, LWB1-8, has reconnaissance Cs dates that verify the annual nature of the cycles. More Cs dates are expected before the meeting. We developed several new methods of verifying the annual nature of our layer counts. The first is looking at the grain size distribution and age of layers with unusually high Mn peaks. Peaks in Si, Ni and Ti and peaks in percentage of coarse material typically accompany the peaks in Mn. Some are visible as yellow sandy layers. The five highest peaks in Mn in LWB1-8 have layer counted ages that correspond (within 1 year in the top meter and within 2 years in the bottom meter) to 1996, 1948, 1913, 1857 and 1790. The latter three events are the three largest historical spring freshets on the Hudson. 1996 is a year of unusually high flow rate during the spring freshet. Based on our work and previous work on Mn cycling in rivers, we infer that the peaks in Mn are produced by extreme erosional events that erode sediment and release pore water Mn into the water column. The other methods of testing our chronology involve marine storms that increase Ca and Sr and a search for fragments of the Peekskill meteorite that fell in October 1992. More information on the latter will be available by the meeting.

  10. Implications of power plant mortality for management of the Hudson River striped bass fishery

    International Nuclear Information System (INIS)

    Goodyear, C.P.

    1988-01-01

    The Atlantic coastal stock of striped bass apparently declined from colonial times to the early 1930s and subsequently recovered. The reasons for the decline and recovery are not known, but fishing remains a possible explanation, which would suggest population sensitivity to increased mortality. Evidence suggests that fishing mortality has been increasing in recent years and will continue to increase in the absence of management intervention. The consequence of increased fishing mortality is an increase in the marginal effect of the power plant mortality which based on the utilities' models and parameter fits, could result in important reductions in the Hudson River striped bass population. Any management actions imposed to arrest population decline or to increase yield per effort in the fishery would be required to mitigate the impact of the power plants by reducing fishing mortality. It is estimated that a 20% conditional power plant mortality is equivalent to a 14% increase in the number of average fishermen using the stock. Consequently, should any management intervention be required on behalf of the population, managers would be required to reduce fishing mortality by about 14% just to account for the power plant mortality. 26 refs., 5 figs., 4 tabs

  11. Large wood in the Snowy River estuary, Australia

    Science.gov (United States)

    Hinwood, Jon B.; McLean, Errol J.

    2017-02-01

    In this paper we report on 8 years of data collection and interpretation of large wood in the Snowy River estuary in southeastern Australia, providing quantitative data on the amount, sources, transport, decay, and geomorphic actions. No prior census data for an estuary is known to the authors despite their environmental and economic importance and the significant differences between a fluvial channel and an estuarine channel. Southeastern Australian estuaries contain a significant quantity of large wood that is derived from many sources, including river flood flows, local bank erosion, and anthropogenic sources. Wind and tide are shown to be as important as river flow in transporting and stranding large wood. Tidal action facilitates trapping of large wood on intertidal bars and shoals; but channels are wider and generally deeper, so log jams are less likely than in rivers. Estuarine large wood contributes to localised scour and accretion and hence to the modification of estuarine habitat, but in the study area it did not have large-scale impacts on the hydraulic gradients nor the geomorphology.

  12. Oceanographic and surface meteorological data collected from station Port of Albany weather/hydro by Hudson River Environmental Conditions Observing System (HRECOS) and assembled by Mid-Atlantic Regional Association Coastal Ocean Observing System (MARACOOS) in the Hudson River from 2011-01-04 to 2017-07-31 (NCEI Accession 0163364)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0163364 contains oceanographic and surface meteorological data collected at Port of Albany weather/hydro, a fixed station in the Hudson River. These...

  13. Oceanographic and surface meteorological data collected from station Schodack Island hydro/weather by Hudson River Environmental Conditions Observing System (HRECOS) and assembled by Mid-Atlantic Regional Association Coastal Ocean Observing System (MARACOOS) in the Hudson River from 2008-04-25 to 2017-05-31 (NCEI Accession 0163416)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0163416 contains oceanographic and surface meteorological data collected at Schodack Island hydro/weather, a fixed station in the Hudson River. These...

  14. The recreational value of river inflows into South African estuaries ...

    African Journals Online (AJOL)

    For the 37 estimates deemed reliable (but not necessarily valid), the average of the predicted median values of river inflow into estuaries was calculated to be 3.4 c/m3 (South African cents, ZAR) and standard deviation 3.84 c/m3. The average of the predicted mean values was calculated to be 7.4 c/m3 and the standard ...

  15. Salt Plug Formation Caused by Decreased River Discharge in a Multi-channel Estuary

    OpenAIRE

    Shaha, Dinesh Chandra; Cho, Yang-Ki

    2016-01-01

    Freshwater input to estuaries may be greatly altered by the river barrages required to meet human needs for drinking water and irrigation and prevent salt water intrusion. Prior studies have examined the salt plugs associated with evaporation and salt outwelling from tidal salt flats in single-channel estuaries. In this work, we discovered a new type of salt plug formation in the multi-channel Pasur River Estuary (PRE) caused by decreasing river discharges resulting from an upstream barrage. ...

  16. 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.

  17. Adult tree swallow survival on the polychlorinated biphenyl-contaminated Hudson River, New York, USA, between 2006 and 2010

    Science.gov (United States)

    Custer, Christine M.; Custer, Thomas W.; Hines, James E.

    2012-01-01

    The upper Hudson River basin in east central New York, USA, is highly contaminated, primarily with polychlorinated biphenyls (PCBs). Reduced adult survival has been documented in tree swallows (Tachycineta bicolor) at a similarly PCB-contaminated river system in western Massachusetts. The purpose of the present study was to assess whether adult survival of tree swallows was likewise affected in the Hudson River basin. Between 2006 and 2010, a total of 521 female tree swallows were banded, of which 148 were retrapped at least once. The authors used Program MARK and an information theoretic approach to test the hypothesis that PCB contamination reduced annual survival of female tree swallows. The model that best described the processes that generated the capture history data included covariate effects of year and female plumage coloration on survival but not PCB/river. Annual survival rates of brown-plumaged females (mostly one year old) were generally lower (mean phi = 0.39) than those of blue-plumaged females (mean phi = 0.50, one year or older). Poor early spring weather in 2007 was associated with reduced survival in both plumage-color groups compared to later years. Models with the effects of PCB exposure on survival (all ΔAICc values >5.0) received little support.

  18. 77 FR 24471 - Takes of Marine Mammals Incidental to Specified Activities; Russian River Estuary Management...

    Science.gov (United States)

    2012-04-24

    ... Marine Mammals Incidental to Specified Activities; Russian River Estuary Management Activities AGENCY...) to incidentally harass, by Level B harassment only, three species of marine mammals during estuary... Estuary Outlet Channel Adaptive Management Plan; and Feasibility of Alternatives to the Goat Rock State...

  19. Oil spill response planning on the Columbia river estuary

    International Nuclear Information System (INIS)

    Christopherson, S.K.; Slyman, P.M.

    1993-01-01

    The Columbia River Estuary lies along the Washington-Oregon state boundary on the west coast of the United States. The entire area is environmentally very sensitive with numerous large, shallow bays, exposed mud flats, wetland areas, and central channels having maximum currents of three to four knots. These features make the area very difficult to protect from an oil spill. Spill response is further complicated because of the many different state, federal, and local jurisdictions with mandated responsibilities in oil spill response and environmental protection. Under the leadership of the US Coast Guard Marine Safety Office in Portland, Oregon, a steering group was established to guide the development of a response plan for the Columbia River Estuary. A concerted effort was made to include representatives from response organizations, natural resource agencies, and resource users from federal, state, and local governments, and commercial sectors in the planning process. The first draft of an operational response plan was completed the summer of 1992 through a combination of technical workshops, field trips, and small working groups meeting with local communities. The Columbia River Estuary Response Plan prioritizes areas to protect; identifies specific response strategies for protecting these areas; and outlines the Iogistics needed to implement these strategies, including equipment needs, the location of staging areas, and the identification of pre-designed command posts. The local spill response cooperative and oil transportation industry are using the plan to coordinate the purchase of response equipment and the staging of this equipment at numerous locations along the river. The key to success is ensuring that all the groups responding to an event participate in the planning process together. This process has worked well and will serve as a model for response planning for other areas along the Columbia River and coastal areas of Washington and Oregon

  20. Trace elements and radionuclides in the Connecticut River and Amazon River estuary

    International Nuclear Information System (INIS)

    Dion, E.P.

    1983-01-01

    The Connecticut River, its estuary and the Amazon River plume were studied to elucidate processes which control the flux of nuclides to the sea. Major ions (Ca, Mg, Na, Cl, Bicarbonate) and selected trace elements (Ra, Ba, Cu, Si) are introduced to the Connecticut River in proportion to the total dissolved load of various groundwaters. Si, Ra, and Ba are subject to removal from solution by seasonal diatom productivity; whereas the other groundwater-derived elements are found in proportion to TDS both time and space. These nuclides are released in the estuary when a portion of the Ra, Ba, and Si in riverine biogenic detritus is trapped in salt marshes and coves bordering the estuary where it redissolves and is exported to the main river channel at ebb tide. In the Amazon River estuary, the Ra and Ba are released in mid-salinity waters. Ra and Ba together with Si are subsequently removed by diatom productivity as reflected in increased Ra and Ba in the suspended particles and depleted dissolved nuclide concentrations in samples from the high productivity zone. In both the Connecticut River system and the Amazon River plume, Cu behaves conservatively; whereas the fates of Fe and Al are linked to soil-derived humic acids. Trace elements in Amazon plume sediments are found simply in proportion to the percentage of fine-grained size materials, despite low Th-228/Ra-228 mean residence times in the plume and the presence of Cs-137 in the sediment column. Estimates of the total flux of nuclides to the oceans can best be calculated on a mass balance basis using groundwater inputs. Unless significant repositories for nuclides exist in the river-estuarine system, the groundwater flux of dissolved nuclides is net flux to the ocean despite the reactions which occur in both rivers and estuaries

  1. Fractionation of rare earth elements in the Mississippi River estuary and river sediments

    Science.gov (United States)

    Adebayo, S. B.; Johannesson, K. H.

    2017-12-01

    This study presents the first set of data on the fractionation of rare earth elements (REE) in the mixing zone between the Mississippi River and the Gulf of Mexico, as well as the fractionation of REE in the operationally defined fractions of Mississippi River sediments. This subject is particularly important because the Mississippi river is one of the world's major rivers, and contributes a substantial amount of water and sediment to the ocean. Hence, it is a major source of trace elements to the oceans. The geochemistry of the REE in natural systems is principally important because of their unique chemical properties, which prompt their application as tracers of mass transportation in modern and paleo-ocean environments. Another important consideration is the growth in the demand and utilization of REE in the green energy and technology industries, which has the potential to bring about a change in the background levels of these trace elements in the environment. The results of this study show a heavy REE enrichment of both the Mississippi River water and the more saline waters of the mixing zone. Our data demonstrate that coagulation and removal of REE in the low salinity region of the estuary is more pronounced among the Light REE ( 35% for Nd) compared to the Heavy REE. Remarkably, our data also indicate that REE removal in the Mississippi River estuary is significantly less than that observed in other estuaries, including the Amazon River system. We propose that the high pH/alkalinity of the Mississippi River is responsible for the greater stability of REE in the Mississippi River estuary. The results of sequential extraction of river sediments reveal different Sm/Nd ratios for the various fractions, which we submit implies different 143Nd/144Nd ratios of the labile fractions of the sediments. The possible impact of such hypothesized different Nd isotope signatures of labile fractions of the river sediments on Gulf of Mexico seawater is under investigation.

  2. Selective analysis of power plant operation on the Hudson River with emphasis on the Bowline Point Generating Station. Volume 2. [Multiple impact of power plant once-through cooling systems on fish populations

    Energy Technology Data Exchange (ETDEWEB)

    Barnthouse, L. W.; Cannon, J. B.; Christensen, S. G.

    1977-07-01

    Because of the location of the Bowline, Roseton, and Indian Point power generating facilities in the low-salinity zone of the Hudson estuary, operation of these plants with the present once-through cooling systems will adversely influence the fish populations that use the area for spawning and initial periods of growth and development. Recruitment rates and standing crops of several fish species may be lowered in response to the increased mortality caused by entrainment of nonscreenable eggs and larvae and by impingement of screenable young of the year. Entrainment and impingement data are particularly relevant for assessing which fish species have the greatest potential for being adversely affected by operation of Bowline, Roseton, and Indian Point with once-through cooling. These data from each of these three plants suggest that the six species that merit the greatest consideration are striped bass, white perch, tomcod, alewife, blueback herring, and bay anchovy. Two points of view are available for assessing the relative importance of the fish species in the Hudson River. From the fisheries point of view, the only two species of major importance are striped bass and shad. From the fish-community and ecosystem point of view, the dominant species, as determined by seasonal and regional standing crops (in numbers and biomass per hectare), are the six species most commonly entrained and impinged, namely, striped bass, white perch, tomcod, alewife, blueback herring, and anchovy.

  3. Methane and nitrous oxide emissions from a subtropical estuary (the Brisbane River estuary, Australia)

    Energy Technology Data Exchange (ETDEWEB)

    Musenze, Ronald S.; Werner, Ursula [Advanced Water Management Centre (AWMC), the University of Queensland, Brisbane, Qld 4072 (Australia); Grinham, Alistair [Advanced Water Management Centre (AWMC), the University of Queensland, Brisbane, Qld 4072 (Australia); School of Civil Engineering, the University of Queensland, Brisbane, Qld 4072 (Australia); Udy, James [Healthy Waterways Ltd, P.O. Box 13086, George Street, Brisbane, Qld 4003 (Australia); Yuan, Zhiguo, E-mail: z.yuan@awmc.uq.edu.au [Advanced Water Management Centre (AWMC), the University of Queensland, Brisbane, Qld 4072 (Australia)

    2014-02-01

    in tropical rivers and polluted estuaries. • Emissions are dominated by N2O, which positively correlated with NOx concentrations. • Currently existing models contribute to uncertainty in emission estimates.

  4. Methane and nitrous oxide emissions from a subtropical estuary (the Brisbane River estuary, Australia)

    International Nuclear Information System (INIS)

    Musenze, Ronald S.; Werner, Ursula; Grinham, Alistair; Udy, James; Yuan, Zhiguo

    2014-01-01

    Methane (CH 4 ) and nitrous oxide (N 2 O) are two key greenhouse gases. Their global atmospheric budgeting is, however, flout with challenges partly due to lack of adequate field studies determining the source strengths. Knowledge and data limitations exist for subtropical and tropical regions especially in the southern latitudes. Surface water methane and nitrous oxide concentrations were measured in a subtropical estuarine system in the southern latitudes in an extensive field study from 2010 to 2012 and water–air fluxes estimated using models considering the effects of both wind and flow induced turbulence. The estuary was found to be a strong net source of both CH 4 and N 2 O all-year-round. Dissolved N 2 O concentrations ranged between 9.1 ± 0.4 to 45.3 ± 1.3 nM or 135 to 435% of atmospheric saturation level, while CH 4 concentrations varied between 31.1 ± 3.7 to 578.4 ± 58.8 nM or 1210 to 26,430% of atmospheric saturation level. These results compare well with measurements from tropical estuarine systems. There was strong spatial variability with both CH 4 and N 2 O concentrations increasing upstream the estuary. Strong temporal variability was also observed but there were no clear seasonal patterns. The degree of N 2 O saturation significantly increased with NO x concentrations (r 2 = 0.55). The estimated water–air fluxes varied between 0.1 and 3.4 mg N 2 O m −2 d −1 and 0.3 to 27.9 mg CH 4 m −2 d −1 . Total emissions (CO 2 -e) were N 2 O (64%) dominated, highlighting the need for reduced nitrogen inputs into the estuary. Choice of the model(s) for estimation of the gas transfer velocity had a big bearing on the estimated total emissions. - Highlights: • The estuary is a strong source of atmospheric methane and nitrous oxide. • Emissions had strong spatial-temporal variability with unclear seasonal patterns. • Dissolved gas saturation comparable to that in tropical rivers and polluted estuaries. • Emissions are dominated by N2O, which

  5. Computer simulation model for the striped bass young-of-the-year population in the Hudson River. [Effects of entrainment and impingement at power plants on population dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Eraslan, A.H.; Van Winkle, W.; Sharp, R.D.; Christensen, S.W.; Goodyear, C.P.; Rush, R.M.; Fulkerson, W.

    1975-09-01

    This report presents a daily transient (tidal-averaged), longitudinally one-dimensional (cross-section-averaged) computer simulation model for the assessment of the entrainment and impingement impacts of power plant operations on young-of-the-year populations of the striped bass, Morone saxatilis, in the Hudson River.

  6. Building sustainable communities using sense of place indicators in three Hudson River Valley, NY, tourism destinations: An application of the limits of acceptable change process

    Science.gov (United States)

    Laura E. Sullivan; Rudy M. Schuster; Diane M. Kuehn; Cheryl S. Doble; Duarte. Morais

    2010-01-01

    This study explores whether measures of residents' sense of place can act as indicators in the Limits of Acceptable Change (LAC) process to facilitate tourism planning and management. Data on community attributes valued by residents and the associated values and meanings were collected through focus groups with 27 residents in three Hudson River Valley, New York,...

  7. Plutonium AMS measurements in Yangtze River estuary sediment

    International Nuclear Information System (INIS)

    Tims, S.G.; Pan, S.M.; Zhang, R.; Fifield, L.K.; Wang, Y.P.; Gao, J.H.

    2010-01-01

    The Yangtze River is the largest single source of sediment to the continental shelf of the East China Sea. The quantity of material exported by the river is expected to decrease substantially as a consequence of an extensive continuing program of dam construction within the river catchment. We report here AMS measurements of plutonium isotope concentrations and ratios for selected depth increments from a sediment core, collected from the sub-aqueous delta of the Yangtze River estuary. The Pu derives from atmospheric nuclear weapons testing in the 1950s and 1960s, and is potentially a useful tracer of sediment deposition times in the marine environment. The results show considerable structure in the depth-concentration profile, and offer an excellent opportunity to compare Pu with the more commonly used 137 Cs isotopic tracer. The AMS data show superior sensitivity and indicate that the 240 Pu/ 239 Pu ratio can provide a check on the deposition dates. The changes in the 240 Pu and 239 Pu concentrations and the 240 Pu/ 239 Pu ratios with sediment depth all indicate the possibility of using Pu as a geochronological tool for coastal sediment studies.

  8. Science, law, and Hudson River power plants: a case study in environmental impact assessment

    National Research Council Canada - National Science Library

    Barnthouse, L. W; Barnthouse, Lawrence W

    1988-01-01

    Scientists spent more than 15 years studying the physical and chemical characteristics and biological productivity of the estuary and documenting the abundance, distribution, and life histories of the major fish species...

  9. Side-Scan_Sonar backscatter tiles for Hudson River, NY (.xtf)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Raw XTF files. Sonar data were collected November 6 to December 15, 2009, in the estuary north from Saugerties to Troy. Data Collection and Processing: The...

  10. 78 FR 1246 - Otay River Estuary Restoration Project; South San Diego Bay Unit and Sweetwater Marsh Unit of the...

    Science.gov (United States)

    2013-01-08

    ...-FF08RSDC00] Otay River Estuary Restoration Project; South San Diego Bay Unit and Sweetwater Marsh Unit of the... scoping with regard to the environmental impact statement (EIS) for the proposed Otay River Estuary... one of the following methods. Email: [email protected] . Please include ``Otay Estuary NOI'' in the...

  11. 76 FR 70480 - Otay River Estuary Restoration Project, South San Diego Bay Unit of the San Diego Bay National...

    Science.gov (United States)

    2011-11-14

    ... River Estuary Restoration Project, South San Diego Bay Unit of the San Diego Bay National Wildlife...), intend to prepare an environmental impact statement (EIS) for the proposed Otay River Estuary Restoration... any one of the following methods. Email: [email protected] . Please include ``Otay Estuary NOI'' in the...

  12. 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

  13. A Study of Sedimentation at the River Estuary on the Change of Reservoir Storage

    OpenAIRE

    Iskahar; Suripin; Isdiyana

    2018-01-01

    Estuary of the river that leads to the reservoir has characteristics include: relatively flat, there is a change in the increase of wet cross-sectional area and backwater. The backwater will cause the flow velocity to be reduced, so that the grains of sediment with a certain diameter carried by the flow will settle in the estuary of the river. The purpose of this research is to know the distribution and sedimentation pattern at the river estuary that leads to the reservoir with the change of ...

  14. Engineering Condition Survey and Evaluation of Troy Lock and Dam, Hudson River, New York Report 2. Evaluation and Rehabilitation.

    Science.gov (United States)

    1981-01-01

    boats in both the spring and fall make seasonal trips from the sunny south to the more mountainous , wooded north, as well as completing many short...back- ground of Troy Lock and Dam 8. The Hudson River originates in the Adirondack Mountains in northern New York State among the highest peaks of the...0.00 0.00 0.00 ___ ___ __ ___ ___ __ __is_ B C BC 25.24 34.14 0.00 0.00 C 25.24 36.00 0. 00 0.06 &M~E ALEA D 3.45 36.00 0.00 6.10 E 3.45 17.00 0.00

  15. Multi-timescale sediment responses across a human impacted river-estuary system

    Science.gov (United States)

    Chen, Yining; Chen, Nengwang; Li, Yan; Hong, Huasheng

    2018-05-01

    Hydrological processes regulating sediment transport from land to sea have been widely studied. However, anthropogenic factors controlling the river flow-sediment regime and subsequent response of the estuary are still poorly understood. Here we conducted a multi-timescale analysis on flow and sediment discharges during the period 1967-2014 for the two tributaries of the Jiulong River in Southeast China. The long-term flow-sediment relationship remained linear in the North River throughout the period, while the linearity showed a remarkable change after 1995 in the West River, largely due to construction of dams and reservoirs in the upland watershed. Over short timescales, rainstorm events caused the changes of suspended sediment concentration (SSC) in the rivers. Regression analysis using synchronous SSC data in a wet season (2009) revealed a delayed response (average 5 days) of the estuary to river input, and a box-model analysis established a quantitative relationship to further describe the response of the estuary to the river sediment input over multiple timescales. The short-term response is determined by both the vertical SSC-salinity changes and the sediment trapping rate in the estuary. However, over the long term, the reduction of riverine sediment yield increased marine sediments trapped into the estuary. The results of this study indicate that human activities (e.g., dams) have substantially altered sediment delivery patterns and river-estuary interactions at multiple timescales.

  16. Research, Monitoring, and Evaluation for the Federal Columbia River Estuary Program

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Diefenderfer, Heida L.; Ebberts, Blaine D.; Tortorici, Cathy; Yerxa, Tracey; Leary, J.; Skalski, John R.

    2008-02-05

    The purpose ofthis document is to describe research, monitoring, and evaluation (RME) for the Federal Columbia River Estuary Program. The intent of this RME effort is to provide data and information to evaluate progress toward meeting program goals and objectives and support decision-making in the Estuary Program. The goal of the Estuary Program is to understand, conserve, and restore the estuary ecosystem to improve the performance of listed salmonid populations. The Estuary Program has five general objectives, designed to fulfill the program goal, as follows. 1. Understand the primary stressors affecting ecosystem controlling factors, such as ocean conditions and invasive species. 2. Conserve and restore factors controlling ecosystem structures and processes, such as hydrodynamics and water quality. 3. Increase the quantity and quality of ecosystem structures, i.e., habitats, juvenile salmonids use during migration through the estuary. 4. Maintain the food web to benefit salmonid performance. 5. Improve salmonid performance in terms of life history diversity, foraging success, growth, and survival. The goal of estuary RME is to provide pertinent and timely research and monitoring information to planners, implementers, and managers of the Estuary Program. In conclusion, the estuary RME effort is designed to meet the research and monitoring needs of the estuary Program using an adaptive management process. Estuary RME's success and usefulness will depend on the actual conduct of adaptive management, as embodied in the objectives, implrementation, data, reporting, and synthesis, evaluation, and decision-making described herein.

  17. Use of an ADCP to compute suspended-sediment discharge in the tidal Hudson River, New York

    Science.gov (United States)

    Wall, Gary R.; Nystrom, Elizabeth A.; Litten, Simon

    2006-01-01

    Acoustic Doppler current profilers (ADCPs) can provide data needed for computation of suspended-sediment discharge in complex river systems, such as tidal rivers, in which conventional methods of collecting time-series data on suspended-sediment concentration (SSC) and water discharge are not feasible. Although ADCPs are not designed to measure SSC, ADCP data can be used as a surrogate under certain environmental conditions. However, the software for such computation is limited, and considerable post-processing is needed to correct and normalize ADCP data for this use. This report documents the sampling design and computational procedure used to calibrate ADCP measures of echo intensity to SSC and water velocity to discharge in the computation of suspended-sediment discharge at the study site on the Hudson River near Poughkeepsie, New York. The methods and procedures described may prove useful to others doing similar work in different locations; however, they are specific to this study site and may have limited applicability elsewhere.

  18. Characteristics of Sediments in the James River Estuary, Virginia, 1968 (NODC Accession 7001081)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This report presents data on the physical and chemical characteristics of bottom sediments in the James River estuary, Virgina. The data were generated as part of a...

  19. Determination of petroleum hydrocarbons in sediment samples from Bombay harbour, Dharamtar creek and Amba river estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Ingole, S.A.; Dhaktode, S.S.; Kadam, A.N.

    The surface sediment samples were collected by van Veen grab sampler during premonsoon, monsoon and postmonsoon seasons from Bombay harbour, Dharamtar creek and Amba river estuary Moisture content of the samples ranges from 36 to 67.5...

  20. 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...

  1. Spatial and vertical distribution of bacteria in the Pearl River estuary ...

    African Journals Online (AJOL)

    Yomi

    2012-01-31

    Jan 31, 2012 ... Key words: Bacterial community structure, the Pearl River estuary, denaturing gradient gel electrophoresis ... change rapidly in response to the change of environ- ..... Chlorinated and polycyclic aromatic hydrocarbons in.

  2. An autonomous underwater vehicle "Maya", for monitoring coastal waters, estuaries, rivers and dams

    Digital Repository Service at National Institute of Oceanography (India)

    Mascarenhas, A.A; Navelkar, G.S.; Madhan, R.; Dabholkar, N.A; Prabhudesai, S.P.; Maurya, P.K.; Desa, E.; Afzulpurkar, S.; Suresh, T.; Matondkar, S.G.P.; Mahalunkar, A

    This article demonstrates the use of Maya, Autonomous Underwater Vehicle (AUV) for monitoring coastal waters, estuaries, rivers and dams. Maya is a mono hull structure with detachable nose and tail cones. The nose cone is mission specific...

  3. Physical aspects of estuarine pollution - A case study in Amba river estuary

    Digital Repository Service at National Institute of Oceanography (India)

    DineshKumar, P.K.; Josanto, V.; Sarma, R.V.; Zingde, M.D.

    Tide dominated Amba river estuary was studied to evaluate it's physical characteristics with a point on application to locate a suitable release point of industrial effluents. It is important to site the outfall in a manner ensuring that the water...

  4. Environmental Settings and Harmful Algal Blooms in the Sea Area Adjacent to the Changjiang River Estuary

    OpenAIRE

    Zhou, Mingjiang

    2010-01-01

    The characteristics of the environmental settings of the sea area adjacent to the Changjiang River estuary include complex currents and water masses, the diluted water plume and its redirection, upwelling, front, and nutrients and their sources. The Changjiang River estuary characteristics also include the phytoplankton community, which can affect the growth, migration, assembling, resting and competition of algae to form red tides in this area.. The features of red tide events recorded in th...

  5. Concentrations, loads, and sources of polychlorinated biphenyls, Neponset River and Neponset River Estuary, eastern Massachusetts

    Science.gov (United States)

    Breault, Robert F.

    2011-01-01

    Polychlorinated biphenyls (PCBs) are known to contaminate the Neponset River, which flows through parts of Boston, Massachusetts, and empties into the Neponset River Estuary, an important fish-spawning area. The river is dammed and impassable to fish. The U.S. Geological Survey, in cooperation with the Massachusetts Department of Fish and Game, Division of Ecological Restoration, Riverways Program, collected, analyzed, and interpreted PCB data from bottom-sediment, water, and (or) fish-tissue samples in 2002, 2004-2006. Samples from the Neponset River and Neponset River Estuary were analyzed for 209 PCB congeners, PCB homologs, and Aroclors. In order to better assess the overall health quality of river-bottom sediments, sediment samples were also tested for concentrations of 31 elements. PCB concentrations measured in the top layers of bottom sediment ranged from 28 nanograms per gram (ng/g) just upstream of the Mother Brook confluence to 24,900 ng/g measured in Mother Brook. Concentrations of elements in bottom sediment were generally higher than background concentrations and higher than levels considered toxic to benthic organisms according to freshwater sediment-quality guidelines defined by the U.S. Environmental Protection Agency. Concentrations of dissolved PCBs in water samples collected from the Neponset River (May 13, 2005 to April 28, 2006) averaged about 9.2 nanograms per liter (ng/L) (annual average of monthly values); however, during the months of August (about 16.5 ng/L) and September (about 15.6 ng/L), dissolved PCB concentrations were greater than 14 ng/L, the U.S. Environmental Protection Agency's freshwater continuous chronic criterion for aquatic organisms. Concentrations of PCBs in white sucker (fillets and whole fish) were all greater than 2,000 ng/g wet wt, the U.S. Environmental Protection Agency's guideline for safe consumption of fish: PCB concentrations measured in fish-tissue samples collected from the Tileston and Hollingsworth and

  6. Heavy Metallic Element Distribution in Cisadane River Estuary's Water and Sediment

    Directory of Open Access Journals (Sweden)

    M. Taufik Kaisupy

    2006-04-01

    Full Text Available Observation of heavy metallic elements in Cisadane River Estuary has been done in July and November 2005. The results show that heavy metallic elements content in seawater is lower and still below the treshold value stated by government for fisheries. There was an indication of heavy metallic elements on sediment. Distribution of Pb on July and of Cu on November 2005 were found higher near the coast and decrease towards the sea, and commonly were found in front of estuary such as Cisadane, Muara Saban and Tanjung Pasir. High Pb and Zn distributions on November 2005 were found only in front of Cisadane estuary. Cd distribution of Cisadane estuary was constant at all station but did not show any correlation with the distance of station and estuary. The Cd content on July and November 2005 is lower than 0,001 ppm. Generally, heavy metallic elements content have a uniform distribution at all stations inspite of its distance to estuary.

  7. A Study of Sedimentation at the River Estuary on the Change of Reservoir Storage

    Directory of Open Access Journals (Sweden)

    Iskahar

    2018-01-01

    Full Text Available Estuary of the river that leads to the reservoir has characteristics include: relatively flat, there is a change in the increase of wet cross-sectional area and backwater. The backwater will cause the flow velocity to be reduced, so that the grains of sediment with a certain diameter carried by the flow will settle in the estuary of the river. The purpose of this research is to know the distribution and sedimentation pattern at the river estuary that leads to the reservoir with the change of water level in the reservoir storage, so the solution can be found to remove / reduce sediment before entering the reservoir. The method used is the experimental, by making the physical model of the river estuary leading to the reservoir. This study expects a solution to reduce sedimentation, so that sedimentation can be removed / minimized before entering the reservoir. This research tries to apply bypass channel to reduce the sedimentation at the river estuary. Bypass channels can be applied to overcome sedimentation at the river estuary, but in order for the sediment to be removed optimally, it is necessary to modify the mouth of bypass channel and channel angle.

  8. Heavy metal anomalies in the Tinto and Odiel River and estuary system, Spain

    Science.gov (United States)

    Nelson, C.H.; Lamothe, P.J.

    1993-01-01

    The Tinto and Odiel rivers drain 100 km from the Rio Tinto sulphide mining district, and join at a 20-km long estuary entering the Atlantic Ocean. A reconnaissance study of heavy metal anomalies in channel sand and overbank mud of the river and estuary by semi-quantitative emission dc-arc spectrographic analysis shows the following upstream to downstream ranges in ppm (??g g-1): As 3,000 to TOC), sandysilty overbank clay has been analyzed to represent suspended load materials. The high content of heavy metals in the overbank clay throughout the river and estuary systems indicates the importance of suspended sediment transport for dispersing heavy metals from natural erosion and anthropogenic mining activities of the sulfide deposit. The organic-poor (0.21-0.37% TOC) river bed sand has been analyzed to represent bedload transport of naturally-occurring sulfide minerals. The sand has high concentrations of metals upstream but these decrease an order of magnitude in the lower estuary. Although heavy metal contamination of estuary mouth beach sand has been diluted to background levels estuary mud exhibits increased contamination apparently related to finer grain size, higher organic carbon content, precipitation of river-borne dissolved solids, and input of anthropogenic heavy metals from industrial sources. The contaminated estuary mud disperses to the inner shelf mud belt and offshore suspended sediment, which exhibit metal anomalies from natural erosion and mining of upstream Rio Tinto sulphide lode sources (Pb, Cu, Zn) and industrial activities within the estuary (Fe, Cr, Ti). Because heavy metal contamination of Tinto-Odiel river sediment reaches or exceeds the highest levels encountered in other river sediments of Spain and Europe, a detailed analysis of metals in water and suspended sediment throughout the system, and epidemiological analysis of heavy metal effects in humans is appropriate. ?? 1993 Estuarine Research Federation.

  9. Methylmercury bioaccumulation in an urban estuary: Delaware River USA.

    Science.gov (United States)

    Buckman, Kate; Taylor, Vivien; Broadley, Hannah; Hocking, Daniel; Balcom, Prentiss; Mason, Rob; Nislow, Keith; Chen, Celia

    2017-09-01

    Spatial variation in mercury (Hg) and methylmercury (MeHg) bioaccumulation in urban coastal watersheds reflects complex interactions between Hg sources, land use, and environmental gradients. We examined MeHg concentrations in fauna from the Delaware River estuary, and related these measurements to environmental parameters and human impacts on the waterway. The sampling sites followed a north to south gradient of increasing salinity, decreasing urban influence, and increasing marsh cover. Although mean total Hg in surface sediments (top 4cm) peaked in the urban estuarine turbidity maximum and generally decreased downstream, surface sediment MeHg concentrations showed no spatial patterns consistent with the examined environmental gradients, indicating urban influence on Hg loading to the sediment but not subsequent methylation. Surface water particulate MeHg concentration showed a positive correlation with marsh cover whereas dissolved MeHg concentrations were slightly elevated in the estuarine turbidity maximum region. Spatial patterns of MeHg bioaccumulation in resident fauna varied across taxa. Small fish showed increased MeHg concentrations in the more urban/industrial sites upstream, with concentrations generally decreasing farther downstream. Invertebrates either showed no clear spatial patterns in MeHg concentrations (blue crabs, fiddler crabs) or increasing concentrations further downstream (grass shrimp). Best-supported linear mixed models relating tissue concentration to environmental variables reflected these complex patterns, with species specific model results dominated by random site effects with a combination of particulate MeHg and landscape variables influencing bioaccumulation in some species. The data strengthen accumulating evidence that bioaccumulation in estuaries can be decoupled from sediment MeHg concentration, and that drivers of MeHg production and fate may vary within a small region.

  10. Pu and 137Cs in the Yangtze River estuary sediments: distribution and source identification.

    Science.gov (United States)

    Liu, Zhiyong; Zheng, Jian; Pan, Shaoming; Dong, Wei; Yamada, Masatoshi; Aono, Tatsuo; Guo, Qiuju

    2011-03-01

    Pu isotopes and (137)Cs were analyzed using sector field ICP-MS and γ spectrometry, respectively, in surface sediment and core sediment samples from the Yangtze River estuary. (239+240)Pu activity and (240)Pu/(239)Pu atom ratios (>0.18) shows a generally increasing trend from land to sea and from north to south in the estuary. This spatial distribution pattern indicates that the Pacific Proving Grounds (PPG) source Pu transported by ocean currents was intensively scavenged into the suspended sediment under favorable conditions, and mixed with riverine sediment as the water circulated in the estuary. This process is the main control for the distribution of Pu in the estuary. Moreover, Pu is also an important indicator for monitoring the changes of environmental radioactivity in the estuary as the river basin is currently the site of extensive human activities and the sea level is rising because of global climate changes. For core sediment samples the maximum peak of (239+240)Pu activity was observed at a depth of 172 cm. The sedimentation rate was estimated on the basis of the Pu maximum deposition peak in 1963-1964 to be 4.1 cm/a. The contributions of the PPG close-in fallout Pu (44%) and the riverine Pu (45%) in Yangtze River estuary sediments are equally important for the total Pu deposition in the estuary, which challenges the current hypothesis that the riverine Pu input was the major source of Pu budget in this area.

  11. Research, Monitoring, and Evaluation for the Federal Columbia River Estuary Program.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Diefenderfer, Heida L. (Pacific Northwest National Laboratory)

    2008-02-20

    The purpose of this document is to describe research, monitoring, and evaluation (RME) for the Federal Columbia River Estuary Program, hereafter called 'the Estuary Program'. The intent of this RME effort is to provide data and information to evaluate progress toward meeting program goals and objectives and support decision making in the Estuary Program. The goal of the Estuary Program is to understand, conserve, and restore the estuary ecosystem to improve the performance of listed salmonid populations. The Estuary Program has five general objectives, designed to fulfill the program goal, as follows: (1) Understand the primary stressors affecting ecosystem controlling factors, such as ocean conditions and invasive species. (2) Conserve and restore factors controlling ecosystem structures and processes, such as hydrodynamics and water quality. (3) Increase the quantity and quality of ecosystem structures, i.e., habitats, juvenile salmonids use during migration through the estuary. (4) Maintain the food web to benefit salmonid performance. (5) Improve salmonid performance in terms of life history diversity, foraging success, growth, and survival. The goal of estuary RME is to provide pertinent and timely research and monitoring information to planners, implementers, and managers of the Estuary Program. The goal leads to three primary management questions pertaining to the main focus of the Estuary Program: estuary habitat conservation and restoration. (1) Are the estuary habitat actions achieving the expected biological and environmental performance targets? (2) Are the offsite habitat actions in the estuary improving juvenile salmonid performance and which actions are most effective at addressing the limiting factors preventing achievement of habitat, fish, or wildlife performance objectives? (3) What are the limiting factors or threats in the estuary/ocean preventing the achievement of desired habitat or fish performance objectives? Performance measures

  12. Embryotoxicity and genotoxicity evaluation of sediments from Yangtze River estuary using zebrafish (Danio rerio) embryos.

    Science.gov (United States)

    Li, Qian; Chen, Ling; Liu, Li; Wu, Lingling

    2016-03-01

    Sediments function both as a sink and a source of pollutants in aquatic ecosystems and may impose serious effects on benthic organisms and human health. As one of the largest estuaries in the world, the Yangtze River estuary suffers from abundant wastewater from the coastal cities. In this study, the zebrafish (Danio rerio) embryos were employed in the fish embryo test and a comet assay to evaluate the embryotoxicity and genotoxicity of the sediments from the Yangtze River estuary, respectively. Results showed that the sediments from the Yangtze River estuary significantly increased mortality, induced development abnormalities, and reduced hatching rate and heart rate of zebrafish embryos after 96 h of exposure. Significant genotoxicity was observed in the samples relative to the controls. Relatively low-level embryotoxicity and genotoxicity of sediments were found in the Yangtze River compared with other river systems. Toxic responses were also discussed in relation to the analyzed organic contaminants in sediments. More attention should be paid to non-priority pollutant monitoring in the Yangtze River estuary.

  13. Pollution in the estuary of the Baracoa river, La Habana, Cuba

    Directory of Open Access Journals (Sweden)

    Regla Duthit Somoza

    2011-04-01

    Full Text Available The environmental quality of the Baracoa river estuary was studied from the physic (temperature and salinity, chemic variables (dissolved oxygen, oxygen biochemical demand (DBO, oxygen chemical demand (DQO, nitrogen cycle, inorganic phosphorus and total phosphorus and the microbiological variables (total and thermotolerant coliforms and faecal streptococci. The samplings were made on February 2006, May and October 2007. Spatial distribution of the physical and chemical parameters measured suggests that the estuary is dominated by the marine conditions. The salinity and temperature analyses show that in general the characteristics of the estuary could be influenced by the contribution of the river basin drainage. In general, the concentrations of the measured parameters in the Baracoa river estuary, strongly suggest that this area is under influence of human activities on the river basin, due to the low levels of dissolved oxygen and an oxygen average deficit of -1.6 mg/L. nthropogenic actions in this estuary are mainly related to the emission of domestic and farming rejects without suitable treatment. This is visibly associated with the observed values of the total coliforms concentrations as well as the concentration of faecal streptococci, that surpassed reference values from the Cuban norm for water quality, following on bad or doubtful quality levels pointing out negatively measurements made next to the communication channel the estuary and the El Doctor lagoon.

  14. Proceedings of the Columbia River Estuary Conference on Ecosystem Restoration.

    Energy Technology Data Exchange (ETDEWEB)

    U.S. Bonneville Power Administration

    2008-08-01

    The 2008 Columbia River Estuary Conference was held at the Liberty Theater in Astoria, Oregon, on April 19-20. The conference theme was ecosystem restoration. The purpose of the conference was to exchange data and information among researchers, policy-makers, and the public, i.e., interrelate science with management. Conference organizers invited presentations synthesizing material on Restoration Planning and Implementation (Session 1), Research to Reduce Restoration Uncertainties (Session 2), Wetlands and Flood Management (Session 3), Action Effectiveness Monitoring (Session 4), and Management Perspectives (Session 5). A series of three plenary talks opened the conference. Facilitated speaker and audience discussion periods were held at the end of each session. Contributed posters conveyed additional data and information. These proceedings include abstracts and notes documenting questions from the audience and clarifying answers from the presenter for each talk. The proceedings also document key points from the discussion periods at the end of each session. The conference program is outlined in the agenda section. Speaker biographies are presented in Appendix A. Poster titles and authors are listed in Appendix B. A list of conference attendees is contained in Appendix C.

  15. From headwaters to coast: Influence of human activities on water quality of the Potomac River Estuary

    Science.gov (United States)

    Bricker, Suzanne B.; Rice, Karen C.; Bricker, Owen P.

    2014-01-01

    The natural aging process of Chesapeake Bay and its tributary estuaries has been accelerated by human activities around the shoreline and within the watershed, increasing sediment and nutrient loads delivered to the bay. Riverine nutrients cause algal growth in the bay leading to reductions in light penetration with consequent declines in sea grass growth, smothering of bottom-dwelling organisms, and decreases in bottom-water dissolved oxygen as algal blooms decay. Historically, bay waters were filtered by oysters, but declines in oyster populations from overfishing and disease have led to higher concentrations of fine-sediment particles and phytoplankton in the water column. Assessments of water and biological resource quality in Chesapeake Bay and tributaries, such as the Potomac River, show a continual degraded state. In this paper, we pay tribute to Owen Bricker’s comprehensive, holistic scientific perspective using an approach that examines the connection between watershed and estuary. We evaluated nitrogen inputs from Potomac River headwaters, nutrient-related conditions within the estuary, and considered the use of shellfish aquaculture as an in-the-water nutrient management measure. Data from headwaters, nontidal, and estuarine portions of the Potomac River watershed and estuary were analyzed to examine the contribution from different parts of the watershed to total nitrogen loads to the estuary. An eutrophication model was applied to these data to evaluate eutrophication status and changes since the early 1990s and for comparison to regional and national conditions. A farm-scale aquaculture model was applied and results scaled to the estuary to determine the potential for shellfish (oyster) aquaculture to mediate eutrophication impacts. Results showed that (1) the contribution to nitrogen loads from headwater streams is small (about 2 %) of total inputs to the Potomac River Estuary; (2) eutrophic conditions in the Potomac River Estuary have improved in

  16. Working with Decision Makers to Improve Energy-Water System Resiliency in the Lower Hudson River Basin

    Science.gov (United States)

    Fellows, J. D.; Schoonen, M. A.; Pullen, J.; González, J. E.; Saleh, F.; Bhatt, V.

    2017-12-01

    Nearly half of the 180 million people living in the eastern U.S. reside in coastal watershed or shoreline counties. The population density of these areas continues to increase, driving an increase in energy-water (EW) system demand and expansion of critical infrastructure. Along with population, these areas are also being stressed by environmental and technology stresses, including climate change. We have been working with decision makers in the Lower Hudson River Basin (LHRB) to develop the tools and data needed to better understand and improve the resiliency of LHRB EW systems facing these kinds of stresses. The LHRB represents: 1) a coastal environment subject to sea level rise that is among the fastest in the East; 2) one of the steepest gradients in population density in the US, with Manhattan the most densely populated coastal county in the nation; 3) a EWN infrastructure serving the largest metropolitan area in the US and the financial center of the world; 4) a history of environmental impacts, ranging from heatwaves, hurricanes to localized storms, that can be used to hindcast; and 5) a wealth of historic and real-time data, extensive monitoring facilities and existing specific sector models that can be leveraged. This presentation will focus on the lessons learned working with the LHRB decision makers.

  17. Sediment-water distribution of perfluorooctane sulfonate (PFOS) in Yangtze River Estuary

    International Nuclear Information System (INIS)

    Pan Gang; You Chun

    2010-01-01

    Analysis of Perfluorooctane sulfonate (PFOS) distribution in water and sediment in Yangtze River Estuary showed that the estuary was a sink for PFOS. Salinity was an important parameter in controlling the sediment-water interactions and the fate or transport of PFOS in the aquatic environment. As the salinity (S per mille ) increased from 0.18 to 3.31, the distribution coefficient (K d ) between sediment and water linearly increased from 0.76 to 4.70 L g -1 . The study suggests that PFOS may be carried with the river water and transported for long distances before it reaches to the sea and largely scavenged to the sediment in the estuaries due to the dramatic change in salinity. - PFOS may be largely scavenged to the sediment in estuaries due to the dramatic change in salinity during its transport from lands to oceans.

  18. VISION, STRATEGY AND ACTION PLAN FOR SHELLFISH FARMING DEVELOPMENT IN THE KRKA RIVER ESTUARY

    Directory of Open Access Journals (Sweden)

    Drago Maguš

    2009-10-01

    Full Text Available In this paper are presented the vision, strategic guidelines/measures and the action plan for shellfish farming development in the Krka river estuary. They came as a result from several discussions that were held with shellfish farmers of the estuary area in year 2008 while writing the Integrated Plan for Shellfish Farming for Krka Estuary Area, which was realized in the framework of the Green Business Support Programme (UNDP COST Project — Conservation, and Sustainable Use of Biodiversity in the Dalmatian Coast through Greening Coastal Development. For a short–term, a considerable impetus for the development of shellfish farming in the Krka river estuary could be the construction of common distribution and purification center, building of warehouse for shellfish farming equipment, and providing work space for the preparation of the equipment as well as the space for waste disposal; for a long–term it could be building of shellfish hatchery at the location of Martinska marine station.

  19. Upriver transport of dissolved substances in an estuary and sub-estuary system of the lower James River, Chesapeake Bay

    Science.gov (United States)

    Hong, Bo; Shen, Jian; Xu, Hongzhou

    2018-01-01

    The water exchange between the James River and the Elizabeth River, an estuary and sub-estuary system in the lower Chesapeake Bay, was investigated using a 3D numerical model. The conservative passive tracers were used to represent the dissolved substances (DS) discharged from the Elizabeth River. The approach enabled us to diagnose the underlying physical processes that control the expansion of the DS, which is representative of potential transport of harmful algae blooms, pollutants from the Elizabeth River to the James River without explicitly simulating biological processes. Model simulations with realistic forcings in 2005, together with a series of processoriented numerical experiments, were conducted to explore the correlations of the transport process and external forcing. Model results show that the upriver transport depends highly on the freshwater discharge on a seasonal scale and maximum upriver transport occurs in summer with a mean transport time ranging from 15-30 days. The southerly/easterly wind, low river discharge, and neap tidal condition all act to strengthen the upriver transport. On the other hand, the northerly/westerly wind, river pulse, water level pulse, and spring tidal condition act to inhibit the upriver transport. Tidal flushing plays an important role in transporting the DS during spring tide, which shortens the travel time in the lower James River. The multivariable regression analysis of volume mean subtidal DS concentration in the mesohaline portion of the James River indicates that DS concentration in the upriver area can be explained and well predicted by the physical forcings (r = 0.858, p = 0.00001).

  20. Particulate organic matter predicts bacterial productivity in a river dominated estuary

    Science.gov (United States)

    Crump, B. C.

    2015-12-01

    Estuaries act as coastal filters for organic and inorganic fluvial materials in which microbial, biogeochemical, and ecological processes combine to transform organic matter and nutrients prior to export to the coastal ocean. The function of this estuarine 'bioreactor' is linked to the residence times of those materials and to rates of microbial heterotrophic activity. Our ability to forecast the impact of global change on estuarine bioreactor function requires an understanding of the basic controls on microbial community activity and diversity. In the Columbia River estuary, the microbial community undergoes a dramatic seasonal shift in species composition during which a spring bacterioplankton community, dominated by Flavobacteriaceae and Oceanospirillales, is replaced by a summer community, dominated by Rhodobacteraceae and several common marine taxa. This annual shift occurs in July, following the spring freshet, when river flow and river chlorophyll concentration decrease and when estuarine water residence time increases. Analysis of a large dataset from 17 research cruises (1990-2014) showed that the composition of particulate organic matter in the estuary changes after the freshet with decreasing organic carbon and nitrogen content, and increasing contribution of marine and autochthonous estuarine organic matter (based on PO13C and pigment ratios). Bacterial production rates (measured as leucine or thymidine incorporation rates) in the estuary respond to this change, and correlate strongly with labile particulate nitrogen concentration and temperature during individual sampling campaigns, and with the concentration of chlorophyll in the Columbia River across all seasons. Regression models suggest that the concentration of labile particulate nitrogen and the rate of bacterial production can be predicted from sensor measurements of turbidity, salinity, and temperature in the estuary and chlorophyll in the river. These results suggest that the quality of

  1. Discontinuous Galerkin modeling of the Columbia River's coupled estuary-plume dynamics

    Science.gov (United States)

    Vallaeys, Valentin; Kärnä, Tuomas; Delandmeter, Philippe; Lambrechts, Jonathan; Baptista, António M.; Deleersnijder, Eric; Hanert, Emmanuel

    2018-04-01

    The Columbia River (CR) estuary is characterized by high river discharge and strong tides that generate high velocity flows and sharp density gradients. Its dynamics strongly affects the coastal ocean circulation. Tidal straining in turn modulates the stratification in the estuary. Simulating the hydrodynamics of the CR estuary and plume therefore requires a multi-scale model as both shelf and estuarine circulations are coupled. Such a model has to keep numerical dissipation as low as possible in order to correctly represent the plume propagation and the salinity intrusion in the estuary. Here, we show that the 3D baroclinic discontinuous Galerkin finite element model SLIM 3D is able to reproduce the main features of the CR estuary-to-ocean continuum. We introduce new vertical discretization and mode splitting that allow us to model a region characterized by complex bathymetry and sharp density and velocity gradients. Our model takes into account the major forcings, i.e. tides, surface wind stress and river discharge, on a single multi-scale grid. The simulation period covers the end of spring-early summer of 2006, a period of high river flow and strong changes in the wind regime. SLIM 3D is validated with in-situ data on the shelf and at multiple locations in the estuary and compared with an operational implementation of SELFE. The model skill in the estuary and on the shelf indicate that SLIM 3D is able to reproduce the key processes driving the river plume dynamics, such as the occurrence of bidirectional plumes or reversals of the inner shelf coastal currents.

  2. Occurrences of dissolved trace metals (Cu, Cd, and Mn) in the Pearl River Estuary (China), a large river-groundwater-estuary system

    Science.gov (United States)

    Wang, Deli; Lin, Wenfang; Yang, Xiqian; Zhai, Weidong; Dai, Minhan; Arthur Chen, Chen-Tung

    2012-12-01

    This study for the first time examined dissolved metals (Cu, Cd, and Mn) together with dissolved oxygen and carbonate system in the whole Pearl River Estuary system, from the upper rivers to the groundwater discharges until the estuarine zone, and explored their potential impacts in the adjacent northern South China Sea (SCS) during May-August 2009. This river-groundwater-estuary system was generally characterized by low dissolved metal levels as a whole, whilst subject to severe perturbations locally. In particular, higher dissolved Cu and Cd occurred in the North River (as high as 60 nmol/L of Cu and 0.99 nmol/L of Cd), as a result of an anthropogenic source from mining activities there. Dissolved Cu levels were elevated in the upper estuary near the city of Guangzhou (Cu: ˜40 nmol/L), which could be attributable to sewage and industrial effluent discharges there. Elevated dissolved metal levels (Cu: ˜20-40 nmol/L; Cd: ˜0.2-0.8 nmol/L) also occurred in the groundwaters and parts of the middle and lower estuaries, which could be attributable to a series of geochemical reactions, e.g., chloride-induced desorption from the suspended sediments, oxidation of metal sulfides, and the partial dissolution of minerals. The high river discharge during our sampling period (May-August 2009) significantly diluted anthropogenic signals in the estuarine mixing zone. Of particular note was the high river discharge (which may reach 18.5 times as high as in the dry season) that transported anthropogenic signals (as indicated by dissolved Cu and Cd) into the adjacent shelf waters of the northern SCS, and might have led to the usually high phytoplankton productivity there (chlorophyll-a value >10 μg/L).

  3. Landscape controls on total and methyl mercury in the upper Hudson River basin of New York State

    Science.gov (United States)

    Burns, D. A.; Murray, K. R.; Bradley, P. M.; Brigham, M. E.; Aiken, G.; Smith, M.

    2010-12-01

    High levels of mercury (Hg) in aquatic biota have been identified in surface waters of the Adirondack region of New York, and factors such as the prevalence of wetlands, extensive forest cover, and oligotrophic waters promote Hg bioaccumulation in this region. Past research in this region has focused on improved understanding of the Hg cycle in lake ecosystems. In the study described herein, the landscape controls on total Hg and methylmercury (MeHg) concentrations in riverine ecosystems were explored through synoptic surveys of 27 sites in the upper Hudson River basin of the Adirondack region. Stream samples were collected and analyzed for total Hg, MeHg, dissolved organic carbon (DOC), and ultraviolet absorbance at 254 nm (UV254) during spring and summer of 2006-08. Landscape indices including many common land cover, hydrographic, and topographic-based measures were explored as predictors of Hg through multivariate linear regression. Multivariate models that included a wetland or riparian area-based metric, an index for open water area, and in some cases a topographic metric such as the wetness index explained 55 to 65 percent of the variation in MeHg concentrations, and 55 to 80 percent of the variation in total Hg concentrations. An open water index (OWI) was developed that incorporated both the basin area drained by ponded water and the surface area of these ponds. This index was inversely related to concentrations of total Hg and MeHg. This OWI was also inversely related to specific ultra-violet absorbance, consistent with previous studies showing that open water increases the influence of algal-derived carbon on DOC, decreasing aromaticity, which should decrease the ability of the dissolved carbon pool to bind Hg. The OWI was not significant in models for total Hg that also included UV254 as a predictive variable, but the index did remain significant in similar models for MeHg suggesting that biogeochemical factors in addition to decreasing carbon

  4. Distribution and flux of 226Ra and 228Ra in the Amazon River estuary

    International Nuclear Information System (INIS)

    Key, R.M.; Sarmiento, J.L.; Stallard, R.F.; Moore, W.S.

    1985-01-01

    Measurements of 226 Ra and 228 Ra in the Amazon River estuary show that desorption from riverborne suspended particulate matter in the estuary increases the riverine flux of both isotopes to the ocean by a factor of approximately 5 over the flux attributable to radium dissolved in the river water alone. The total Amazon flux supplies approximately 0.20% of the 226 Ra and approximately 2.6% of the 228 Ra standing crops in the near-surface Atlantic (0-200 m). Diffusive flux from estuarine and shelf sediments and desorption from resuspended sediments in the region of the estuary approximately double the estuarine 226 Ra concentration and quadruple the estuarine 228 Ra concentration above that caused by the dissolved and desorbed river components alone

  5. Distribution and sources of polycyclic aromatic hydrocarbons in surface sediments of rivers and an estuary in Shanghai, China

    International Nuclear Information System (INIS)

    Ying Liu; Ling Chen; Zhao Jianfu; Huang Qinghui; Zhu Zhiliang; Gao Hongwen

    2008-01-01

    Concentrations, spatial distribution and sources of 17 polycyclic aromatic hydrocarbons (PAHs) and methylnaphthalene were investigated in surface sediments of rivers and an estuary in Shanghai, China. Total PAH concentrations, excluding perylene, ranged from 107 to 1707 ng/g-dw. Sedimentary PAH concentrations of the Huangpu River were higher than those of the Yangtze Estuary. The concentration of the Suzhou River was close to the average concentration of the Huangpu River. PAHs source analysis suggested that, in the Yangtze Estuary, PAHs at locations far away from cities were mainly from petrogenic sources. At other locations, both petrogenic and pyrogenic inputs were significant. In the Huangpu and Suzhou Rivers, pyrogenic input outweighed other sources. The pyrogenic PAHs in the upper reaches of the Huangpu River were mainly from the incomplete combustion of grass, wood and coal, and those in the middle and lower reaches were from vehicle and vessel exhaust. - Surface sediments of two rivers and an estuary in Shanghai were contaminated by PAHs

  6. Some physico-chemical aspects of pollution in the Karnafully river estuary

    International Nuclear Information System (INIS)

    Islam, M.N.; Zamal, H.; Anwar, M.N.; Saha, S.B.

    2003-01-01

    An investigation was carried out to determine the characteristics of low tide water of Karnafully river estuary during January to December 1997. The study reveals that low tide water of the estuary is highly turbid which inhibits penetration of incident light (K t =16.66) and limits the euphotic zone within a narrow depth of 0.19 m. The estuarine water is oligohaline and neutral in nature and remains under-saturated with dissolved oxygen throughout the year. The load of different nutrients is higher than that of the world average of river water. (author)

  7. Evaluation of a barrier net used to mitigate fish impingement at a Hudson River power plant intake

    International Nuclear Information System (INIS)

    Hutchison, J.B.; Matousek, J.A.

    1988-01-01

    A multifilament nylon net of 0.95-cm bar mesh was deployed as a physical barrier to fish in front of the Bowline Point power plant cooling water intake on the Hudson River from 1976 to 1985. The barrier net was deployed during the historical peak impingement months of October-May. The primary species impinged on the intake screens during this period were young-of-year and yearling white perch, striped bass, rainbow smelt, alewife, blue-back herring, and American shad, generally ranging from 5 to 10 cm in total length. When the barrier net was deployed, median impingement of all fish was 91% lower than during comparable periods before the net was installed. A mark-recapture population estimate indicated that 230,000 yearling striped bass and white perch were in the embayment outside the net in April 1982; over a 9-d study period, only 1.6% of this estimated population was impinged. Concurrent survival probability studies of fish marked and released at locations inside and outside the barrier net showed that fish released inside had 72% lower survival (P

  8. Salt Plug Formation Caused by Decreased River Discharge in a Multi-channel Estuary

    Science.gov (United States)

    Shaha, Dinesh Chandra; Cho, Yang-Ki

    2016-01-01

    Freshwater input to estuaries may be greatly altered by the river barrages required to meet human needs for drinking water and irrigation and prevent salt water intrusion. Prior studies have examined the salt plugs associated with evaporation and salt outwelling from tidal salt flats in single-channel estuaries. In this work, we discovered a new type of salt plug formation in the multi-channel Pasur River Estuary (PRE) caused by decreasing river discharges resulting from an upstream barrage. The formation of a salt plug in response to changes in river discharge was investigated using a conductivity-temperature-depth (CTD) recorder during spring and neap tides in the dry and wet seasons in 2014. An exportation of saline water from the Shibsa River Estuary (SRE) to the PRE through the Chunkhuri Channel occurred during the dry season, and a salt plug was created and persisted from December to June near Chalna in the PRE. A discharge-induced, relatively high water level in the PRE during the wet season exerted hydrostatic pressure towards the SRE from the PRE and thereby prevented the intrusion of salt water from the SRE to the PRE. PMID:27255892

  9. Biogeochemical transport in the Loxahatchee River estuary, FL: The role of submarine groundwater discharge

    Science.gov (United States)

    Swarzenski, P.; Orem, B.; McPherson, B.; Baskaran, M.; Wan, Y.

    2005-05-01

    The distributions of dissolved organic carbon (DOC), silica, select trace elements (Mn, Fe, Ba, Sr, Co, V,) and a suite of naturally-occurring radionuclides in the U/Th decay series (222Rn, 223,224,226,228Ra, 238U) were studied during high and low discharge conditions in the Loxahatchee River estuary, Florida. The zero-salinity endmember of this still relatively pristine estuary may reflect not only river-borne constituents, but also those advected during active groundwater/surface-water discharge. During low discharge conditions, with the notable exception of Co, trace metals indicate nearly conservative mixing from a salinity of ~12 through the estuary (This statement contracdicts with what is said in p. 7). In contrast, of the trace metals studied, only Sr, Fe, U and V exhibited conservative estuarine mixing during high discharge. Dissolved organic carbon and Si concentrations were highest at zero salinities, and generally decreased with an increase in salinity during both discharge regimes, indicating removal of land-derived dissolved organic matter and silica in the estuary. Suspended particulate matter (SPM) concentrations were generally lowest ( 28 dpm L-1) at the freshwater endmember of the estuary, and appear to identify regions of the river most influenced by active submarine groundwater discharge (where is the data that show this?). Activities of four naturally-occurring isotopes of Ra (223,224,226,228Ra) in this estuary and select adjacent shallow groundwater wells indicate mean estuarine water mass residence times of less than 1 day; values in close agreement to those calculated by tidal prism and tidal period. A radium-based model for estimating submarine groundwater discharge to the Loxahatchee River estuary yielded an average of 1.03 V 3.84 x 105 m3 day-1, depending on river discharge stage as well as slight variations in the particular Ra models used. Such calculated flux estimates are in close agreement with results obtained from a 2-day

  10. Polychlorinated biphenyls in adult black bass and yellow perch were not associated with their reproductive success in the upper Hudson River, New York, USA.

    Science.gov (United States)

    Maceina, Michael J; Sammons, Steven M

    2013-07-01

    Although production and use of polychlorinated biphenyls (PCBs) ceased nearly 35 yr ago, questions still remain concerning the potential chronic effects these compounds may have on wild fish, including their reproductive success. In the upper Hudson River, New York, USA, fish were exposed to PCBs primarily from 2 manufacturing plants located approximately 320 km upstream of New York City, New York, from the 1940s to 1977. The authors collected yellow perch (Perca flavescens), smallmouth bass (Micropterus dolomieu), and largemouth bass (M. salmoides) using electrofishing, measured PCBs in these adults, and estimated abundance and size of their offspring at age 1 yr (age-1 fish). Fish were collected annually from 2004 to 2009 from 1 control site upstream of the PCB discharge sites and from 2 sites downstream from where PCBs were released. These sites (pools) are separated by a series of dams, locks, and canals. Muscle tissue wet weight PCB and lipid-based PCB concentrations in adults in the 2 PCB exposure pools averaged approximately 1 to 3 µg/g and 100 to 500 µg/g, respectively. Age-1 abundances were not related to adult PCB concentrations but were inversely related to river flow. Size of age-1 fish was slightly greater at the PCB-exposure sites. Levels of PCBs in yellow perch, largemouth bass, and smallmouth bass in the upper Hudson River did not impair or reduce recruitment or reproductive success. Copyright © 2013 SETAC.

  11. Hazard Assessment from Storm Tides and Rainfall on a Tidal River Estuary

    Science.gov (United States)

    Orton, P.; Conticello, F.; Cioffi, F.; Hall, T.; Georgas, N.; Lall, U.; Blumberg, A.

    2015-01-01

    Here, we report on methods and results for a model-based flood hazard assessment we have conducted for the Hudson River from New York City to Troy/Albany at the head of tide. Our recent work showed that neglecting freshwater flows leads to underestimation of peak water levels at up-river sites and neglecting stratification (typical with two-dimensional modeling) leads to underestimation all along the Hudson. As a result, we use a three-dimensional hydrodynamic model and merge streamflows and storm tides from tropical and extratropical cyclones (TCs, ETCs), as well as wet extratropical cyclone (WETC) floods (e.g. freshets, rain-on-snow events). We validate the modeled flood levels and quantify error with comparisons to 76 historical events. A Bayesian statistical method is developed for tropical cyclone streamflows using historical data and consisting in the evaluation of (1) the peak discharge and its pdf as a function of TC characteristics, and (2) the temporal trend of the hydrograph as a function of temporal evolution of the cyclone track, its intensity and the response characteristics of the specific basin. A k-nearest-neighbors method is employed to determine the hydrograph shape. Out of sample validation tests demonstrate the effectiveness of the method. Thus, the combined effects of storm surge and runoff produced by tropical cyclones hitting the New York area can be included in flood hazard assessment. Results for the upper Hudson (Albany) suggest a dominance of WETCs, for the lower Hudson (at New York Harbor) a case where ETCs are dominant for shorter return periods and TCs are more important for longer return periods (over 150 years), and for the middle-Hudson (Poughkeepsie) a mix of all three flood events types is important. However, a possible low-bias for TC flood levels is inferred from a lower importance in the assessment results, versus historical event top-20 lists, and this will be further evaluated as these preliminary methods and results are

  12. Late Holocene (~ 2 ka) East Asian Monsoon variations inferred from river discharge and climate interrelationships in the Pearl River Estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Nan, Q.; Li, T.; Chen, J.; Nigam, R.

    A sediment core from the Pearl River Estuary (PRE) was analyzed for grain size and organic geochemistry parameters (TOC and δ13Corg). The results showed that high mean grain-size value and increased sand content were correlated...

  13. Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2005

    Energy Technology Data Exchange (ETDEWEB)

    Diefenderfer, Heida L.; Thom, Ronald M.; Borde, Amy B.; Roegner, G. C.; Whiting, Allan H.; Johnson, Gary E.; Dawley, Earl; Skalski, John R.; Vavrinec, John; Ebberts, Blaine D.

    2006-12-20

    This report is the second annual report of a six-year project to evaluate the cumulative effects of habitat restoration projects in the Columbia River Estuary, conducted by Pacific Northwest National Laboratory's Marine Sciences Laboratory, NOAA's National Marine Fisheries Service Pt. Adams Biological Field Station, and the Columbia River Estuary Study Taskforce for the US Army Corps of Engineers. In 2005, baseline data were collected on two restoration sites and two associated reference sites in the Columbia River estuary. The sites represent two habitat types of the estuary--brackish marsh and freshwater swamp--that have sustained substantial losses in area and that may play important roles for salmonids. Baseline data collected included vegetation and elevation surveys, above and below-ground biomass, water depth and temperature, nutrient flux, fish species composition, and channel geometry. Following baseline data collection, three kinds of restoration actions for hydrological reconnection were implemented in several locations on the sites: tidegate replacements (2) at Vera Slough, near the city of Astoria in Oregon State, and culvert replacements (2) and dike breaches (3) at Kandoll Farm in the Grays River watershed in Washington State. Limited post-restoration data were collected: photo points, nutrient flux, water depth and temperature, and channel cross-sections. In subsequent work, this and additional post-restoration data will be used in conjunction with data from other sites to estimate net effects of hydrological reconnection restoration projects throughout the estuary. This project is establishing methods for evaluating the effectiveness of individual projects and a framework for assessing estuary-wide cumulative effects including a protocol manual for monitoring restoration and reference sites.

  14. Pollution history of the Savannah River estuary. Final report, September 1, 1976--December 31, 1977

    International Nuclear Information System (INIS)

    Goldberg, E.D.; Hodge, V.; Griffin, J.J.; Koide, M.; Windom, H.

    1978-04-01

    Records of natural and pollutant fluxes to the Savannah River Estuary are found in some river and marsh deposits into which time frames can be introduced by Pb-210 or plutonium geochronologies. Plutonium releases from the Savannah River Plant are evident in only one deposit and in marsh grass which received the transuranic element from atmospheric transport. The pollution records can be disturbed by bioturbative activities of organisms, by the input of marine solid phases to the estuarine deposits, and by river scour and fill

  15. Nutrient Budgets and Management Actions in the Patuxent River Estuary, Maryland

    Science.gov (United States)

    Multi-year nitrogen (N) and phosphorus (P) budgets were developed for the Patuxent River estuary, a seasonally stratified and moderately eutrophic tributary of Chesapeake Bay. Major inputs (point, diffuse, septic and direct atmospheric) were measured for 13 years during which la...

  16. Current status of non-native fish species in the St. Louis River estuary

    Science.gov (United States)

    The fish community of the St. Louis River estuary is well characterized, thanks to fishery assessment and invasive species early detection monitoring by federal, state, and tribal agencies. This sampling includes long-standing adult/juvenile fish surveys, larval fish surveys beg...

  17. The fish community of the Berg River estuary and an assessment of ...

    African Journals Online (AJOL)

    Zoology Department and Marine Biology Research Institute, University of Cape Town, Rondebosch, 7700. Republic of South Africa. Received I May 1993; accepted 6 October /993. Data concerning the species composition, abundance and distribution of fishes inhab~ing the Berg River estuary are presented and used to ...

  18. Spatial and vertical distribution of bacteria in the Pearl River estuary ...

    African Journals Online (AJOL)

    In order to investigate the spatial and vertical change of bacteria community structure in the Pearl River estuary sediment, denaturing gradient gel electrophoresis (DGGE) and multivariate statistical analyses were carried out in this study. Results of multidimensional scaling analyses (MDS) were in good agreement with the ...

  19. Protocols for Monitoring Habitat Restoration Projects in the Lower Columbia River and Estuary

    Energy Technology Data Exchange (ETDEWEB)

    Roegner, G. Curtis; Diefenderfer, Heida L.; Borde, Amy B.; Thom, Ronald M.; Dawley, Earl M.; Whiting, Allan H.; Zimmerman, Shon A.; Johnson, Gary E.

    2008-04-25

    Protocols for monitoring salmon habitat restoration projects are essential for the U.S. Army Corps of Engineers' environmental efforts in the Columbia River estuary. This manual provides state-of-the science data collection and analysis methods for landscape features, water quality, and fish species composition, among others.

  20. Investigating phenology of larval fishes in St. Louis River estuary shallow water habitats

    Science.gov (United States)

    As part of the development of an early detection monitoring strategy for non-native fishes, larval fish surveys have been conducted since 2012 in the St. Louis River estuary. Survey data demonstrates there is considerable variability in fish abundance and species assemblages acro...

  1. A numerical study of the plume in Cape Fear River Estuary and adjacent coastal ocean

    Science.gov (United States)

    Xia, M.; Xia, L.; Pietrafesa, L. J.

    2006-12-01

    Cape Fear River Estuary (CFRE), located in southeast North Carolina, is the only river estuary system in the state which is directly connected to the Atlantic Ocean. It is also an important nursery for economically and ecologically important juvenile fish, crabs, shrimp, and other species because of the tidal influence and saline waters. In this study, Environmental Fluid Dynamic Code (EFDC) is used to simulate the salinity plume and trajectory distribution at the mouth of the CFRE and adjacent coastal ocean. Prescribed with the climatological freshwater discharge rates in the rivers, the modeling system was used to simulate the salinity plume and trajectory distribution distribution in the mouth of the CFRE under the influence of climatological wind conditions and tidal effect. We analyzed the plume formation processes and the strong relationship between the various plume distributions with respect to the wind and river discharge in the region. The simulations also indicate that strong winds tend to reduce the surface CFRE plume size and distorting the bulge region near the estuary mouth due to enhanced wind induced surface mixing. Even moderate wind speeds could fully reverse the buoyancy-driven plume structure in CFRE under normal river discharge conditions. Tide and the river discharge also are important factors to influence the plume structure. The comparions between the distribution of salinity plume and trajectory also are discussed in the study.

  2. Influence of the Three Gorges Project on saltwater intrusion in the Yangtze River Estuary

    Science.gov (United States)

    An, Qiang; Wu, Yanqing; Taylor, Shauna; Zhao, Bin

    2009-02-01

    The Three Gorges Project (TGP) is a transcentury project that has aroused world attention. It is expected that the flow velocity and runoff of the Yangtze River will be changed after the project has been accomplished. Consequently, however, the ecological environment in the Yangtze River Basin, particularly in the estuary region, will be affected. Salinity intrusion into the Yangtze River estuary, in general, is mostly affected by the Yangtze River discharge and its external tidal level. This paper focuses on examining the influence of changes in runoff on salinity value. The question, to which should be paid attention is: how is the interaction between changes in runoff of the Yangtze River and salinity distribution in the Yangtze River estuary, China? In this research, a three-dimensional model has been used to identify the effects of runoff change on salinity distribution. The drawn conclusion is that the change of salinity is influenced by discharge variation. Positive and negative impacts of TGP would both turn up but in different period. In sum, TGP is in favor of restraining saltwater intrusion. Nevertheless a suitable method should be found to resolve its negative influences.

  3. Use of glacier river-fed estuary channels by juvenile coho salmon: transitional or rearing habitats?

    Science.gov (United States)

    Hoem Neher, Tammy D.; Rosenberger, Amanda E.; Zimmerman, Christian E.; Walker, Coowe M.; Baird, Steven J.

    2014-01-01

    Estuaries are among the most productive ecosystems in the world and provide important rearing environments for a variety of fish species. Though generally considered important transitional habitats for smolting salmon, little is known about the role that estuaries serve for rearing and the environmental conditions important for salmon. We illustrate how juvenile coho salmonOncorhynchus kisutch use a glacial river-fed estuary based on examination of spatial and seasonal variability in patterns of abundance, fish size, age structure, condition, and local habitat use. Fish abundance was greater in deeper channels with cooler and less variable temperatures, and these habitats were consistently occupied throughout the season. Variability in channel depth and water temperature was negatively associated with fish abundance. Fish size was negatively related to site distance from the upper extent of the tidal influence, while fish condition did not relate to channel location within the estuary ecotone. Our work demonstrates the potential this glacially-fed estuary serves as both transitional and rearing habitat for juvenile coho salmon during smolt emigration to the ocean, and patterns of fish distribution within the estuary correspond to environmental conditions.

  4. Flushing characteristics of Amba river estuary, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    DineshKumar, P.K.; Sarma, R.V.; Josanto, V.

    of 22 tidal cycles for neap, 6 to 7 tidal cycles for spring and dry weather flushing time of 45 tidal cycles for neap, 6 to 7 tidal cycles for spring based on modified tidal prism method indicated that the load retained in the estuary after infinite...

  5. Environmental studies of the Ambika and associated river estuaries

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Narvekar, P.V.; Sharma, P.; Sabnis, M.M.

    loads quantified. High sea water influx, strong currents and small low tide volume rendered the estuaries well mixed with excellent flushing characteristics. The fraction of freshwater method gave a flushing time of 2.5 and 5.8 tidal cycles in October...

  6. Physico-chemical investigations in Auranga river estuary (Gujarat)

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Sharma, P.; Sabnis, M.M.

    currents. The flushing time calculated (2.7-4.1 tidal cycles) by applying the fraction of fresh water method was at least three times higher than computed on the basis of the tidal prism method. The load retained in the estuary under continuous flow...

  7. Heavy Metallic Element Distribution in Cisadane River Estuary's Water and Sediment

    OpenAIRE

    M. Taufik Kaisupy; Abdul Rozak; Endang Rochyatun

    2006-01-01

    Observation of heavy metallic elements in Cisadane River Estuary has been done in July and November 2005. The results show that heavy metallic elements content in seawater is lower and still below the treshold value stated by government for fisheries. There was an indication of heavy metallic elements on sediment. Distribution of Pb on July and of Cu on November 2005 were found higher near the coast and decrease towards the sea, and commonly were found in front of estuary such as Cisadane, Mu...

  8. A water-quality study of the tidal Potomac River and Estuary: An overview

    Science.gov (United States)

    Callendar, Edward; Carter, Virginia; Hahl, D.C.; Hitt, Kerie; Schultz, Barbara I.

    1984-01-01

    The U.S. Geological Survey began a 5-year interdisciplinary study of the tidal Potomac River and Estuary in October of 1977. The objectives of the study are: (1) to provide a basic understanding of physical, chemical, and biological processes; (2) to develop flow and transport models to predict the movement and fate of nutrients and algaes and (3) to develop efficient techniques for the study of tidal rivers and estuaries. The ultimate goal is to aid water-quality decision-making for the tidal Potomac River and Estuary. The study is being conducted by scientists from many disciplines involved in 14 interrelated studies. These scientists are addressing five major problem areas: nutrient enrichment, algal blooms, dissolved oxygen, sedimentation, and effects of water quality on living resources. Preliminary results show that treatment of sewage has reduced the concentration load of organic carbon and phosphorus below that of the 1960's and 1970's, and changed the form of dissolved nitrogen in the tidal river. Concentrations of chlorophyll a during the study period were lower than those experienced during the massive algal blooms of the 1960's. Dissolved oxygen concentrations fluctuate in response to changes in algal populations, but remain above the Environmental Protection Agency limits during the summer low-flow period. Sedimentation rates have accelerated during the past 50-70 years due to urbanization and farming. Asian clams have recently invaded the tidal river; submersed aquatic vegetation has declined since the early 1900's, but conditions may now favor its return.

  9. Sandbar Formation in the Mesjid River Estuary, Rupat Strait, Riau Province, Indonesia

    Directory of Open Access Journals (Sweden)

    Rifardi Rifardi

    2017-07-01

    Full Text Available At the aim to clarify the relationship between the sandbar  formation and lithogeneous sediment discharges, the sedimentological aspects of the Mesjid River Estuary are revealed by various analysis. The samples of bottom surface sediments and the suspended sediment were collected at 50 stations in the estuary using grab and van dorm samplers. Oceanographic observation were also carried out  at the stations. The Mesjid River Estuary receives lithogeneous sediments mainly from the Mesjid River’s drainage areas which play important role on the formation of sandbar which is shown by  a belt-like area (0.5-1.0 m depth in the area off the river mouth. The sandbar might become a sandbank in 20 to 40 years later. High suspended sediment up to 354.61 mg/l indicates the river mouth receives lithogeneous sediments. Total of 926  ton/day of the sediments supplied by the river are deposited 0.024 m/year into the area.

  10. Source identification, geochemical normalization and influence factors of heavy metals in Yangtze River Estuary sediment.

    Science.gov (United States)

    Sun, Xueshi; Fan, Dejiang; Liu, Ming; Tian, Yuan; Pang, Yue; Liao, Huijie

    2018-06-18

    Sediment samples, including 40 surface samples and 12 sediment cores, were collected from 52 stations of the Yangtze River Estuary (YRE) in 2015 and 2016. The 95% linear prediction intervals (LPI) and principal components analysis (PCA), were conducted to evaluate the metal sources and grain-size effect (GSE). The in situ physico-chemical properties of pH, Eh, DO, salinity, temperature and turbidity were combined to elucidate the relationships between environmental factors and the fate of heavy metals in the river-estuary-shelf system. This study indicates a decreasing trend of metals in sediments from the estuary towards the adjacent shelf and the river channel and that Zn, Cu and Cr are mainly derived from natural processes throughout the catchment, whereas Pb appears to have anthropogenic inputs via atmospheric deposition. Furthermore, considering the best fit regression lines between the concentrations of Al and heavy metals as well as the deficiencies of the conventional C elements /C Al method, we introduce an approach (Al-SN: Al-scope normalization) that can eliminate the GSE on heavy metals and be applied to other estuaries. After Al-scope normalization, the relatively constant levels of Zn, Cu and Cr that remain in sediments from the river channel to the estuary and shelf confirmed that the variation of grain size in sediments almost entirely explained the distribution patterns of sediment toxicity in the YRE, while the enrichment of Pb in estuarine sediments could be attributed to its chemical species and physico-chemical properties. The results further suggest that the relationship between grain size and spatial behavior of sediment pollutants should be given priority over the contamination assessment and provenance discrimination in estuarine or similar environments with complex sediment compositions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Plutonium speciation and isotope ratios in Yenisey and Ob river and Yenisey estuary

    International Nuclear Information System (INIS)

    Skipperud, L.; Oughton, DH.; Fifield, K.; Lind, O.C.; Salbu, B.; Brown, J.

    2004-01-01

    Plutonium isotope ratios are known to vary with reactor type, nuclear fuel-burn up time, neutron flux, and energy, and for fallout from nuclear detonations, weapon type and yield. Weapons-grade plutonium is characterized by a low content of the 240 Pu isotope, with 240 Pu/ 239 Pu isotope ratio less than 0.05. In contrast, both global weapons fallout and spent nuclear fuel from civil reactors have higher 240 Pu/ 239 Pu isotope ratios (civil nuclear power reactors have 240 Pu/ 239 Pu atom ratios of between about 0.2-1). Thus, different sources often exhibit characteristic plutonium isotope ratios and these ratios can be used to identify the origin of contamination, calculate inventories, or follow the migration of contaminated sediments and waters. Together with activity measurements and isotope ratios, knowledge of plutonium speciation in the Ob and Yenisey rivers and processes controlling its behaviour in estuarine systems is a prerequisite for predicting the transfer and subsequent environmental impact to Arctic Seas. With this in mind, the study had two objectives: first to determine whether discharges from nuclear installations in the river catchment areas are having any influence on Pu levels in the estuaries; and, second, to investigate the transfer and mobility of plutonium in the Yenisey river and estuary. Plutonium 240/239 ratios were determined using accelerator mass spectrometry (AMS). The data indicated a clear influence from a low 240 Pu: 239 Pu source in surface sediments collected from the Yenisey Estuary, whereas plutonium in the Ob Estuary sediments are dominated by global fallout. The results also show an increase in plutonium concentration and a decrease in isotope ratio going upstream from the estuary. Sequential extractions of sediments indicate that up 70% of the Pu in the Yenisey river is easily mobilized with weak oxidizing agents, which indicates that the Pu is organically bound, while the Pu is more strongly irreversible bound further out

  12. Reduced river discharge intensifies phytoplankton bloom in Godavari estuary, India

    Digital Repository Service at National Institute of Oceanography (India)

    Acharyya, T.; Sarma, V.V.S.S.; Sridevi, B.; Venkataramana, V.; Bharathi, M.D.; Naidu, S.A.; Kumar, B.S.K.; Prasad, V.R.; Bandyopadhyay, D.; Reddy, N.P.C.; DileepKumar, M.

    et al., 2009; Sarma et al., 2011), behaviour of different 3 elements (Sarma et al., 1993) and heavy metals (Somayajulu et al., 1993).Virtually no systematic studies have been undertaken so far in these estuaries focussing on spatial and... their class specific marker pigment fucoxanthin (Jeffry et al., 1997; Mantoura and Llewellyn, 1983; Wright et al., 1991). To confirm the influence of SPM and flushing time on phytoplankton bloom a laboratory- based incubation experiment was conducted...

  13. The physico-chemical characteristics of Imo River Estuary in ...

    African Journals Online (AJOL)

    Sampling was done monthly at fishing grounds in the estuary designated upper, middle and lower course, respectively. Mean water temperature was 26.2°C; transparency, 58.66cm and salinity, 12.66‰. Total dissolved solids, total suspended solids, and total solids had means of 7.91mg/l, 11.91 and 19.82mg/l, respectively.

  14. Place branding and endogenous rural development. Departure points for developing an inner brand for the River Minho estuary

    NARCIS (Netherlands)

    Dominguez Garcia, M.D.; Horlings, L.G.; Swagemakers, P.; Simón Fernández, X.

    2013-01-01

    Place branding holds a promising contribution to sustainable territorial development and requires changes in the social organisation of places, which implies complex transitional processes towards new management regimes. This article explores place branding of the River Minho estuary in the

  15. Current status of emerging hypoxia in a eutrophic estuary: The lower reach of the Pearl River Estuary, China

    Science.gov (United States)

    Qian, Wei; Gan, Jianping; Liu, Jinwen; He, Biyan; Lu, Zhongming; Guo, Xianghui; Wang, Deli; Guo, Liguo; Huang, Tao; Dai, Minhan

    2018-05-01

    We examine the current status of dissolved oxygen (DO) and its trend over the past 25 years in the lower Pearl River Estuary, a large eutrophic estuary located in Southern China and surrounded by large cities including Hong Kong, Shenzhen and Guangzhou. Monthly cruises conducted from April 2010 to March 2011 clearly show that DO depletion began to emerge in the bottom layer of the lower estuary off Hong Kong in June, and became fully developed in July and August when oxygen-deficient water occupied ∼1000 km2 before gradually becoming re-oxygenated in September and October. The development of the low oxygen zone was closely coupled with phytoplankton blooms in the surface water, which was supersaturated with respect to DO suggesting the importance of autochthonous organic matter in fueling bottom DO consumption after settling through the pycnocline. Long-term monitoring data collected in the study area adjacent to Hong Kong by the Hong Kong Environmental Protection Department showed a decreasing trend of ∼2 ± 0.9 μmol kg-1 yr-1 in the annual minimum DO concentration in bottom water over the past 25 years. Associated with the decrease in DO was an increase in the annual maximum surface concentration of dissolved inorganic nitrogen (DIN) at a rate of ∼1.4 ± 0.3 μmol kg-1 yr-1, suggesting again that eutrophication is the most plausible driver of oxygen deficiency in this region. Therefore, our monthly cruises, along with the decadal monitoring data, reveal a large low oxygen zone, likely developing into a large hypoxic zone driven primarily by anthropogenic eutrophication. This new development suggests environmental stressors such as eutrophication may have a cascading effect, with important and expensive consequences for the regional environment.

  16. Effects of Nitrogen Availability and Form on Phytoplankton Growth in a Eutrophied Estuary (Neuse River Estuary, NC, USA)

    Science.gov (United States)

    Paerl, Hans W.; Wetz, Michael S.

    2016-01-01

    Nitrogen availability and form are important controls on estuarine phytoplankton growth. This study experimentally determined the influence of urea and nitrate additions on phytoplankton growth throughout the growing season (March 2012, June 2011, August 2011) in a temperate, eutrophied estuary (Neuse River Estuary, North Carolina, USA). Photopigments (chlorophyll a and diagnostic photopigments: peridinin, fucoxanthin, alloxanthin, zeaxanthin, chlorophyll b) and microscopy-based cell counts were used as indicators of phytoplankton growth. In March, the phytoplankton community was dominated by Gyrodinium instriatum and only fucoxanthin-based growth rates were stimulated by nitrogen addition. The limited response to nitrogen suggests other factors may control phytoplankton growth and community composition in early spring. In June, inorganic nitrogen concentrations were low and stimulatory effects of both nitrogen forms were observed for chlorophyll a- and diagnostic photopigment-based growth rates. In contrast, cell counts showed that only cryptophyte and dinoflagellate (Heterocapsa rotundata) growth were stimulated. Responses of other photopigments may have been due to an increase in pigment per cell or growth of plankton too small to be counted with the microscopic methods used. Despite high nitrate concentrations in August, growth rates were elevated in response to urea and/or nitrate addition for all photopigments except peridinin. However, this response was not observed in cell counts, again suggesting that pigment-based growth responses may not always be indicative of a true community and/or taxa-specific growth response. This highlights the need to employ targeted microscopy-based cell enumeration concurrent with pigment-based technology to facilitate a more complete understanding of phytoplankton dynamics in estuarine systems. These results are consistent with previous studies showing the seasonal importance of nitrogen availability in estuaries, and also

  17. Effects of Nitrogen Availability and Form on Phytoplankton Growth in a Eutrophied Estuary (Neuse River Estuary, NC, USA).

    Science.gov (United States)

    Cira, Emily K; Paerl, Hans W; Wetz, Michael S

    2016-01-01

    Nitrogen availability and form are important controls on estuarine phytoplankton growth. This study experimentally determined the influence of urea and nitrate additions on phytoplankton growth throughout the growing season (March 2012, June 2011, August 2011) in a temperate, eutrophied estuary (Neuse River Estuary, North Carolina, USA). Photopigments (chlorophyll a and diagnostic photopigments: peridinin, fucoxanthin, alloxanthin, zeaxanthin, chlorophyll b) and microscopy-based cell counts were used as indicators of phytoplankton growth. In March, the phytoplankton community was dominated by Gyrodinium instriatum and only fucoxanthin-based growth rates were stimulated by nitrogen addition. The limited response to nitrogen suggests other factors may control phytoplankton growth and community composition in early spring. In June, inorganic nitrogen concentrations were low and stimulatory effects of both nitrogen forms were observed for chlorophyll a- and diagnostic photopigment-based growth rates. In contrast, cell counts showed that only cryptophyte and dinoflagellate (Heterocapsa rotundata) growth were stimulated. Responses of other photopigments may have been due to an increase in pigment per cell or growth of plankton too small to be counted with the microscopic methods used. Despite high nitrate concentrations in August, growth rates were elevated in response to urea and/or nitrate addition for all photopigments except peridinin. However, this response was not observed in cell counts, again suggesting that pigment-based growth responses may not always be indicative of a true community and/or taxa-specific growth response. This highlights the need to employ targeted microscopy-based cell enumeration concurrent with pigment-based technology to facilitate a more complete understanding of phytoplankton dynamics in estuarine systems. These results are consistent with previous studies showing the seasonal importance of nitrogen availability in estuaries, and also

  18. 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

  19. Particulate and dissolved organic carbon and chlorophyll A in the Zaire river, estuary and plume

    Science.gov (United States)

    Cadée, G. C.

    Data were collected on POC, DOC and phytoplankton in the Zaire river, estuary and plume. Mean river value for POC was 1.1 mg·l -1, 4.7% of the suspended matter. Average DOC content of the river water was 8.5 mg·l -1. These values are in accordance with the calculations of TOC input from rivers to the world's ocean. Within the estuary POC and chlorophyll decreased regularly up to a salinity of 20. Between salinities of 20 and 32 small phytoplankton bloom occurred resulting also in higher POC values. DOC mixed conservatively up to a salinity of 25; at salinities above 25, values indicate DOC production. This DOC production occurred partly in the bottom water of the canyon where low oxygen values indicated mineralization and conversion of the accumulated POC into DOC. Another area of DOC production observed inside and outside the surface waters of the plume, was partly related to autolysis and degradation of the phytoplankton bloom. This study shows that the influence of rivers on the organic carbon in the ocean will not be confined to the amount introduced directly, but that we have to add the amounts of POC and DOC resulting from enhanced phytoplankton primary production by nutrient input from rivers and by river induced upwelling.

  20. Towards a sustainable future in Hudson Bay

    International Nuclear Information System (INIS)

    Okrainetz, G.

    1991-01-01

    To date, ca $40-50 billion has been invested in or committed to hydroelectric development on the rivers feeding Hudson Bay. In addition, billions more have been invested in land uses such as forestry and mining within the Hudson Bay drainage basin. However, there has never been a study of the possible impacts on Hudson Bay resulting from this activity. Neither has there been any federal environmental assessment on any of the economic developments that affect Hudson Bay. To fill this gap in knowledge, the Hudson Bay Program was established. The program will not conduct scientific field research but will rather scan the published literature and consult with leading experts in an effort to identify biophysical factors that are likely to be significantly affected by the cumulative influence of hydroelectric and other developments within and outside the region. An annotated bibliography on Hudson Bay has been completed and used to prepare a science overview paper, which will be circulated for comment, revised, and used as the basis for a workshop on cumulative effects in Hudson Bay. Papers will then be commissioned for a second workshop to be held in fall 1993. A unique feature of the program is its integration of traditional ecological knowledge among the Inuit and Cree communities around Hudson Bay with the scientific approach to cumulative impact assessment. One goal of the program is to help these communities bring forward their knowledge in such a way that it can be integrated into the cumulative effects assessment

  1. Carbonate system and nutrients in the Pearl River estuary, China: Seasonal and inter-annual variations

    Science.gov (United States)

    Guo, X.

    2017-12-01

    Located in southern China and surrounded by several metropolis, the Pearl River estuary is a large subtropical estuary under significant human perturbation. We examined the impact of sewage treatment rate on the water environmental factors. Carbonate system parameters (Dissolved inorganic carbon or DIC, Total alkalinity or TA, and pH), and nutrients were surveyed in the Pearl River estuary from 2000 to 2015. Spatially, concentrations of nutrients were high at low salinity and decreased with salinity in both wet and dry seasons although seasonal variation occurred. However, distribution patterns of DIC and TA differed in wet and dry seasons. In wet season, both DIC and TA were low at low salinity (600-1500 umol kg-1) and increased with salinity, but in dry season they were high at low salinity (3000-3500 umol kg-1) and decreased with salinity. Compared with the years before 2010, both values and distribution patterns of DIC, TA and pH were similar among the years in wet season, but they were conspicuously different in the upper estuary in dry season. Both DIC and TA were more than 1000 umol kg-1 lower than those in the years before 2010. For nutrients at low salinity, the ammonia concentration was much lower in the years after 2010 (200 vs. 400 umol kg-1 in wet season and 400 vs. 800 umol kg-1 in dry season), but nitrate concentration was slightly higher (180 vs 120 mmol kg-1 in wet season and 200 vs 180 mmol kg-1 in dry season). As a reference, carbonate system parameters and nutrients were stable among the 16 years in the adjacent northern South China Sea. The variations in biogeochemical processes induced by nutrients concentration and structure as a result of sewage discharge will be discussed in detail. The decrease in DIC, TA and nutrients in the upper Pearl River estuary after 2010 was due mainly to the improvement of sewage treatment rate and capacity.

  2. Importance of a winter dinoflagellate-microflagellate bloom in the Patuxent River estuary

    Science.gov (United States)

    Sellner, K. G.; Lacouture, R. V.; Cibik, S. J.; Brindley, A.; Brownlee, S. G.

    1991-01-01

    A dense bloom of Katodinium rotundatum was observed in the Patuxent River estuary from December to February 1989. The dinoflagellate dominated phytoplankton densities reaching 10 8 cells l -1 and contributed up to 1900 μgC l -1 in near-surface depths. The bloom maintained a distinct patch extending over 10-25 km of the estuary or approximately one-third to one-half of the total estuary (salinities from 5-13 ppt) and was restricted to regions immediately upriver of the transition between the shallow upriver (3-4 m) and deeper lower estuary (10 m). Daily measurements collected in the primary bloom area at the same time each day in the study area indicated 80- and 120-fold variations in chlorophyll and cell densities from day to day. Densities of potential grazers in the region were high with rotifers, primarily Synchaeta baltica, reaching densities of 1000 l -1 in early winter, and the copepod Eurytemora affinis reaching levels exceeding 1·15 × 10 5 m -3 in February. Estimates of grazing pressure by these planktonic herbivores indicated substantial grazing losses for the bloom, with up to 67% of bloom biomass consumed day -1 in February. Nutrient concentrations and ratios of N/P during the bloom suggested potentially N-limited conditions; bloom demise was coincident with a shift to high N/P ratios and high river flows. These data as well as other historical data suggest that dinoflagellate blooms in the lower Patuxent River estuary could be the primary source of carbon to the system during the winter and supply a large reservoir of labile organic matter to planktonic secondary producers prior to annual spring diatom blooms in the region.

  3. Geochemical behaviour of plutonium isotopes in natural media (lakes, rivers, estuaries)

    International Nuclear Information System (INIS)

    Jeandel, C.P.

    1981-10-01

    Artificial radionuclide activities ( 238 Pu, 239+240 Pu) were measured in natural environments. Their distribution and geochemical behaviour are evaluated and compared them to these of the 137 Cs. In a volcanic crater lake, influenced only by atmospheric fallout (Lac Pavin, France), sediments are enriched in 239+240 Pu, whereas 137 Cs stays in the dissolved phase. Diffusion processes and migration of radionuclides is shown to occur in sediments. Remobilization of 239+240 Pu is probable at the sediment/water interface. In the Garonne-Dordogne, Seine and Loire rivers, the 239+240 Pu activity levels in suspended matter are little influenced by the waste discharges of nuclear power plants. The element is essentially transported in the particulate fraction, more than is 137 Cs. In all the esturies studied (Gironde, Seine, Loire) 239+240 Pu concentrations in suspended matter increase between the river and the estuary. Simultaneously a removal of plutonium from the dissolved phase is observed. High plutonium concentrations are measured in the Seine estuary; they are attributed to a ''marine'' contamination: the French nuclear reprocessing plant of La Hague discharges low level radioactive liquid wastes, a part may reach the Seine estuary. There are no decrease in particulate 137 Cs concentrations between the river and the estuary of the Gironde, such as it occurs in the Loire. In this last case, the phenomenon is explained by the presence of ''young caesium'' originating in the power plant effluents and which is more exchangeable than 137 Cs of atmospheric origin. In the Seine estuary, the influence of marine contamination causes an increase of particulate and dissolved 137 Cs concentrations [fr

  4. Evaluation of Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Diefenderfer, Heida L.; Thom, Ronald M.; Roegner, G. Curtis; Ebberts, Blaine D.; Skalski, John R.; Borde, Amy B.; Dawley, Earl; Coleman, Andre M.; Woodruff, Dana L.; Breithaupt, Stephen A.; Cameron, April; Corbett, C.; Donley, Erin E.; Jay, D. A.; Ke, Yinghai; Leffler, K.; McNeil, C.; Studebaker, Cindy; Tagestad, Jerry D.

    2012-05-01

    This is the seventh and final annual report of a project (2004–2010) addressing evaluation of the cumulative effects of habitat restoration actions in the 235-km-long lower Columbia River and estuary. The project, called the Cumulative Effects (CE) study, was conducted for the U.S. Army Corps of Engineers Portland District by a collaboration of research agencies led by the Pacific Northwest National Laboratory. We achieved the primary goal of the CE study to develop a methodology to evaluate the cumulative effects of habitat actions in the Columbia Estuary Ecosystem Restoration Program. We delivered 1) standard monitoring protocols and methods to prioritize monitoring activities; 2) the theoretical and empirical basis for a CE methodology using levels-of-evidence; 3) evaluations of cumulative effects using ecological relationships, geo-referenced data, hydrodynamic modeling, and meta-analyses; and 4) an adaptive management process to coordinate and coalesce restoration efforts in the LCRE. A solid foundation has been laid for future comprehensive evaluations of progress made by the Columbia Estuary Ecosystem Restoration Program to understand, conserve, and restore ecosystems in the lower Columbia River and estuary.

  5. A retrospective streamflow ensemble forecast for an extreme hydrologic event: a case study of Hurricane Irene and on the Hudson River basin

    Science.gov (United States)

    Saleh, Firas; Ramaswamy, Venkatsundar; Georgas, Nickitas; Blumberg, Alan F.; Pullen, Julie

    2016-07-01

    This paper investigates the uncertainties in hourly streamflow ensemble forecasts for an extreme hydrological event using a hydrological model forced with short-range ensemble weather prediction models. A state-of-the art, automated, short-term hydrologic prediction framework was implemented using GIS and a regional scale hydrological model (HEC-HMS). The hydrologic framework was applied to the Hudson River basin ( ˜ 36 000 km2) in the United States using gridded precipitation data from the National Centers for Environmental Prediction (NCEP) North American Regional Reanalysis (NARR) and was validated against streamflow observations from the United States Geologic Survey (USGS). Finally, 21 precipitation ensemble members of the latest Global Ensemble Forecast System (GEFS/R) were forced into HEC-HMS to generate a retrospective streamflow ensemble forecast for an extreme hydrological event, Hurricane Irene. The work shows that ensemble stream discharge forecasts provide improved predictions and useful information about associated uncertainties, thus improving the assessment of risks when compared with deterministic forecasts. The uncertainties in weather inputs may result in false warnings and missed river flooding events, reducing the potential to effectively mitigate flood damage. The findings demonstrate how errors in the ensemble median streamflow forecast and time of peak, as well as the ensemble spread (uncertainty) are reduced 48 h pre-event by utilizing the ensemble framework. The methodology and implications of this work benefit efforts of short-term streamflow forecasts at regional scales, notably regarding the peak timing of an extreme hydrologic event when combined with a flood threshold exceedance diagram. Although the modeling framework was implemented on the Hudson River basin, it is flexible and applicable in other parts of the world where atmospheric reanalysis products and streamflow data are available.

  6. Radionuclide tracers for the fate of metals in the Savannah estuary: River-ocean exchange processes

    International Nuclear Information System (INIS)

    Olsen, C.R.; Thein, M.; Larsen, I.L.; Byrd, J.T.; Windom, H.L.

    1989-01-01

    Plutonium-238 from the US Department of Energy's Savannah River Plant labels riverborne particles, providing a unique opportunity for examining the fate of metals in estuaries and for tracing river-ocean exchange processes. Results indicate that plutonium and lead-210 are enriched on estuarine particles and that inputs of plutonium from oceanic sources greatly exceed inputs from riverborne or drainage-basin sources as far upstream as the landward limit of seawater penetration. We suggest that these radionuclides (and other chemically reactive metals) are being scavenged from oceanic water by sorption onto particles in turbid estuarine and coastal areas. Since estuaries, bays, mangroves, and intertidal areas serve as effective traps for fine particles and associated trace substances, these results have important implications concerning the disposal of chemically reactive substances in oceanic waters. 13 refs., 1 fig., 1 tab

  7. Spatial Distribution of Lead and Copper in the Bottom Sediments of Pahang River Estuary, Pahang, Malaysia

    International Nuclear Information System (INIS)

    Kamaruzzaman Yunus; Siti Waznah Ahmad; Chuan, O.M.; Bidai, J.

    2010-01-01

    Bottom sediment samples from 30 stations of Pahang River estuary collected in April 2008 were analyzed for the concentration of Pb and Cu using the Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The average concentrations of Pb and Cu were 74.31 ± 22.97 μg/ g dry weights and 18.65± 7.65 μg/ g dry weights, respectively. In this study, the concentrations were significantly higher near the mouth river and declined as the sampling points were further away from the estuary. Generally, the concentrations of heavy metals were relatively low when compare with other studies in Malaysia. However, the calculated enrichment factors (EF) obtained for Pb, has a slightly higher value, and was probably influenced by anthropogenic input. The concentration for both metals increased with the decrease of mean size, suggesting their association with the fine fraction of the sediments. (author)

  8. Metal surveys in South African estuaries I. Swartkops River

    International Nuclear Information System (INIS)

    Watling, R.J.; Watling, H.R.

    1982-01-01

    Water, surface sediment and sediment core samples were collected from sites in the Swartkops River up to 15 km from the mouth and analysed for up to sixteen elements. The results indicate the presence of four main areas of contamination in the river, at Redhouse, Swartkops, the brickworks and Amsterdam Hoek. The accumulation of zinc, copper, lead and nickel by oysters grown at the mouth of the river confirms the presence of greater than normal metal concentrations in the river. Fish-water Flats outfall contributes metals to the nearshore marine environment, but the strong tidal sweep disperses the effluent relatively quickly so that metal build-up in the area is minimal. In general, metal levels in the Swartkops River are low and, as yet, the area cannot be described as 'polluted' in the true sense of the word

  9. Sources, fluxes, and behaviors of fluorescent dissolved organic matter (FDOM) in the Nakdong River Estuary, Korea

    Science.gov (United States)

    Lee, Shin-Ah; Kim, Guebuem

    2018-02-01

    We monitored seasonal variations in dissolved organic carbon (DOC), the stable carbon isotope of DOC (δ13C-DOC), and fluorescent dissolved organic matter (FDOM) in water samples from a fixed station in the Nakdong River Estuary, Korea. Sampling was performed every hour during spring tide once a month from October 2014 to August 2015. The concentrations of DOC and humic-like FDOM showed significant negative correlations against salinity (r2 = 0.42-0.98, p ocean.

  10. Simulation of chlorinated water discharges from power plants on estuaries and rivers

    International Nuclear Information System (INIS)

    Eraslan, A.H.; Lietzke, M.H.; Fischer, S.K.; Kalmaz, E.V.

    1977-01-01

    The fast-transient (tidal-transient) one-dimensional discrete-element chemical transport model and its associated computer code CHMONE were applied to study the effects of chlorinated water discharges from power plants on tidal estuaries and controlled rivers. The mathematical model has the capability to predict simultaneously the hydrodynamic, thermal, and chemical composition of water as one-dimensional time-dependent distributions

  11. Nike (Awaous melanocephalus) Fishery and Mercury Contamination in the Estuary of BoneBolango River

    OpenAIRE

    Aziz Salam; Femy M Sahami; Citra Panigoro

    2016-01-01

    Nike fish (Awaous melanocephalus) is a tiny-kind of fish harvested lunar-monthly in the estuary of BoneBolango River in the City of Gorontalo. The fishing activity is showing steady increase recently as the commodity finds its way to the international market. Fishermen are putting more efforts by escalating the catching capacity of their gears. Meanwhile, mercury used by the artisanal and small-scale gold mining (ASGM) in the headwaters for amalgamation put another aspect to the A...

  12. Multi-Scale Action Effectiveness Research in the Lower Columbia River and Estuary, 2012

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Sather, Nichole K.; Storch, Adam; Johnson, Jeff; Skalski, J. R.; Teel, D. J.; Brewer, Taylor; Bryson, Amanda J.; Dawley, Earl M.; Kuligowski, D. R.; Whitesel, T.; Mallette, Christine

    2013-11-30

    The study reported herein was conducted for the U.S. Army Corps of Engineers, Portland District (USACE) by researchers at the Pacific Northwest National Laboratory (PNNL), Oregon Department of Fish and Wildlife (ODFW), National Marine Fisheries Service (NMFS), University of Washington (UW), and U.S. Fish and Wildlife Service (USFWS). The goal of the study was to evaluate the ecological benefits of restoration actions for juvenile salmon in the lower Columbia River and estuary (LCRE; rkm 0–234).

  13. Distribution, sources and ecological risk assessment of PAHs in surface sediments from the Luan River Estuary, China.

    Science.gov (United States)

    Zhang, Daolai; Liu, Jinqing; Jiang, Xuejun; Cao, Ke; Yin, Ping; Zhang, Xunhua

    2016-01-15

    The distribution, sources and risk assessment of 16 polycyclic aromatic hydrocarbons (PAHs) of surface sediments in the Luan River Estuary, China, have been investigated in the research. The results indicated that the total concentrations of 16 PAHs in surface sediments of the Luan River Estuary ranged from 5.1 to 545.1 ng g(-1)dw with a mean value of 120.8 ng g(-1)dw, which is relatively low in comparison with other estuaries around the world. The PAHs in the study area were mainly originated from pyrogenic sources. Besides, PAHs may be contaminated by petrogenic PAHs as indicated by the selected ratios of PAHs, the 2-tailed Pearson correlation analysis and principal components analysis at different sites. The result of the ecological risk assessment shows little negative effect for most individual PAHs in surface sediments of the Luan River Estuary, China. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Lower Columbia River and Estuary Habitat Monitoring Study, 2011 - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Borde, Amy B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kaufmann, Ronald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cullinan, Valerie I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zimmerman, Shon A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thom, Ronald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wright, Cynthia L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2012-03-01

    The Ecosystem Monitoring Program is a collaborative effort between the Lower Columbia River Estuary Partnership (LCREP), University of Washington, Wetland Ecosystem Team (UW), US Geological Survey, Water Science Center (USGS), National Oceanic and Atmospheric Administration, National Marine Fisheries Service (NOAA-Fisheries, hereafter NOAA), and Pacific Northwest National Laboratory, Marine Sciences Laboratory (PNNL). The goal of the program is to conduct emergent wetland monitoring aimed at characterizing salmonid habitats in the lower Columbia River and estuary (LCRE) from the mouth of the estuary to Bonneville Dam (Figure 1). This is an ecosystem based monitoring program focused on evaluating status and trends in habitat and reducing uncertainties regarding these ecosystems to ultimately improve the survival of juvenile salmonids through the LCRE. This project comprehensively assesses habitat, fish, food web, and abiotic conditions in the lower river, focusing on shallow water and vegetated habitats used by juvenile salmonids for feeding, rearing and refugia. The information is intended to be used to guide management actions associated with species recovery, particularly that of threatened and endangered salmonids. PNNL’s role in this multi-year study is to monitor the habitat structure (e.g., vegetation, topography, channel morphology, and sediment type) as well as hydrologic patterns.

  15. Macrozoobenthos Community Structure In The Estuary of Donan River, Cilacap, Central Java Province, Indonesia

    Directory of Open Access Journals (Sweden)

    Taufik Fakih Hakiki

    2017-12-01

    Full Text Available Estuary of Donan Riverwhich is adjacent to Segara Anakan Lagoon in Cilacap, Central Java Province (Indonesia has been used for a number of activities such asfishieries, agriculture, industry, harbor, and tourism activities.  The aim of this study is to analyze the ecosystem condition based on mazcrozoobenthos community structure. This study was conducted from Augustus 2015 to January 2016. Samples were collected monthly at five stations from the river close area to the ocean close area. The study was conducted to identify kinds of generaand densityof themacrozoobenthos, and analyze substrates and water quality.Data analysis was performed onabundance, diversity, evenness and dominance indexes.Based on the study, macrozoobenthos at the estuary of Donan River consists of three classes i.e Gastropod (12 genera, Bivalvia(9 genera, and Polychaeta (6 genera. Based on the sampling location, Gastropod and Bivalvia are the largest composition found at five stations. Based on the sampling location, the macrozoobenthos density, diversity index, evennes index,and dominance index can be inferred that the estuary of Donan River is classified to be moderately ecological polluted.

  16. Migratory Behavior and Survival of Juvenile Salmonids in the Lower Columbia River and Estuary in 2009

    Energy Technology Data Exchange (ETDEWEB)

    McMichael, Geoffrey A.; Harnish, Ryan A.; Bellgraph, Brian J.; Carter, Jessica A.; Ham, Kenneth D.; Titzler, P. Scott; Hughes, Michael S.

    2010-08-01

    The study reported herein was funded as part of the Anadromous Fish Evaluation Program, which is managed by the U.S. Army Corps of Engineers (USACE). The Anadromous Fish Evaluation Program study code is EST P 02 01: A Study of Salmonid Survival and Behavior through the Columbia River Estuary Using Acoustic Tags. The study was conducted by the Pacific Northwest National Laboratory (PNNL) and National Oceanic and Atmospheric Administration (NOAA) Fisheries for the USACE Portland District. Estimated survival of acoustic-tagged juvenile Chinook salmon and steelhead through the lower Columbia River and estuary in 2009 was lowest in the final 50 km of the estuary. Probability of survival was relatively high (>0.90) for yearling and subyearling Chinook salmon from the Bonneville Dam forebay (rkm 236) to Three-tree Point (rkm 49.6). Survival of juvenile Chinook salmon declined sharply through the lower 50 km of the estuary. Acoustic-tagged steelhead smolts did not survive as well as juvenile Chinook salmon between Bonneville Dam and the mouth of the Columbia River. Steelhead survival began to decline farther upstream (at rkm 86) relative to that of the Chinook salmon stocks. Subyearling Chinook salmon survival decreased markedly as the season progressed. It remains to be determined whether later migrating subyearling Chinook salmon are suffering increasing mortality as the season progresses or whether some portion of the apparent loss is due to fish extending their freshwater residence. This study provided the first glimpse into what promises to be a very informative way to learn more about how juvenile salmonid passage experiences through the FCRPS may influence their subsequent survival after passing Bonneville Dam. New information regarding the influence of migration pathway through the lower 50 km of the Columbia River estuary on probability of survival of juvenile salmonids, combined with increased understanding regarding the foraging distances and time periods of

  17. Restoration of Hydrodynamic and Hydrologic Processes in the Chinook River Estuary, Washington ? Feasibility Assessment

    International Nuclear Information System (INIS)

    Khangaonkar, Tarang P.; Breithaupt, Stephen A.; Kristanovich, Felix C.

    2006-01-01

    A hydrodynamic and hydrologic modeling analysis was conducted to evaluate the feasibility of restoring natural estuarine functions and tidal marine wetlands habitat in the Chinook River estuary, located near the mouth of the Columbia River in Washington. The reduction in salmonid populations is attributable primarily to the construction of a Highway 101 overpass across the mouth of the Chinook River in the early 1920s with a tide gate under the overpass. This construction, which was designed to eliminate tidal action in the estuary, has impeded the upstream passage of salmonids. The goal of the Chinook River Restoration Project is to restore tidal functions through the estuary, by removing the tide gate at the mouth of the river, filling drainage ditches, restoring tidal swales, and reforesting riparian areas. The hydrologic model (HEC-HMS) was used to compute Chinook River and tributary inflows for use as input to the hydrodynamic model at the project area boundary. The hydrodynamic model (RMA-10) was used to generate information on water levels, velocities, salinity, and inundation during both normal tides and 100-year storm conditions under existing conditions and under the restoration alternatives. The RMA-10 model was extended well upstream of the normal tidal flats into the watershed domain to correctly simulate flooding and drainage with tidal effects included, using the wetting and drying schemes. The major conclusion of the hydrologic and hydrodynamic modeling study was that restoration of the tidal functions in the Chinook River estuary would be feasible through opening or removal of the tide gate. Implementation of the preferred alternative (removal of the tide gate, restoration of the channel under Hwy 101 to a 200-foot width, and construction of an internal levee inside the project area) would provide the required restorations benefits (inundation, habitat, velocities, and salinity penetration, etc.) and meet flood protection requirements. The

  18. Sediment accumulation and mixing in the Penobscot River and estuary, Maine.

    Science.gov (United States)

    Yeager, K M; Schwehr, K A; Schindler, K J; Santschi, P H

    2018-04-16

    Mercury (Hg) was discharged in the late 1960s into the Penobscot River by the Holtra-Chem chlor-alkali production facility, which was in operation from 1967 to 2000. To assess the transport and distribution of total Hg, and recovery of the river and estuary system from Hg pollution, physical and radiochemical data were assembled from sediment cores collected from 58 of 72 coring stations sampled in 2009. These stations were located throughout the lower Penobscot River, and included four principal study regions, the Penobscot River (PBR), Mendall Marsh (MM), the Orland River (OR), and the Penobscot estuary (ES). To provide the geochronology required to evaluate sedimentary total Hg profiles, 58 of 72 sediment cores were dated using the atmospheric radionuclide tracers 137 Cs, 210 Pb, and 239,240 Pu. Sediment cores were assessed for depths of mixing, and for the determination of sediment accumulation rates using both geochemical (total Hg) and radiochemical data. At most stations, evidence for significant vertical mixing, derived from profiles of 7 Be (where possible) and porosity, was restricted to the upper ~1-3cm. Thus, historic profiles of both total Hg and radionuclides were only minimally distorted, allowing a reconstruction of their depositional history. The pulse input tracers 137 Cs and 239,240 Pu used to assess sediment accumulation rates agreed well, while the steady state tracer 210 Pb exhibited weaker agreement, likely due to irregular lateral sediment inputs. Copyright © 2018. Published by Elsevier B.V.

  19. Contribution of wave-induced liquefaction in triggering hyperpycnal flows in Yellow River Estuary

    Science.gov (United States)

    Liu, X.; Jia, Y.

    2017-12-01

    Hyperpycnal flows, driven mainly by the gravity of near-bed negatively buoyant layers, are one of the most important processes for moving marine sediment across the earth. The issue of hyperpycnal flows existing in marine environment has drawn increasing scholars' attention since that was observed in situ off the Yellow River estuary in the 1980s. Most researches maintain that hyperpycnal flows in the Yellow River estuary are caused by the high-concentration sediments discharged from the Yellow River into sea, however, other mechanisms have been discounted since the sediment input from the river has been significantly changed due to climate and anthropogenic change. Here we demonstrate that wave-seabed interactions can generate hyperpycnal flows, without river input, by sediment flux convergence above an originally consolidated seabed. Using physical model experiments and multi-sensor field measurements, we characterize the composition-dependent liquefaction properties of the sediment due to wave-induced pore water pressure accumulation. This allows quantification of attenuation of sediment threshold velocity and critical shear stress (predominant variables in transport mechanics) during the liquefaction under waves. Parameterising the wave-seabed interactions in a new concept model shows that high waves propagating over the seabed sediment can act as a scarifier plough remoulding the seabed sediment. This contributes to marine hyperpycnal flows as the sediment is quickly resuspended under accumulating attenuation in strength. Therefore, the development of more integrative numerical models could supply realistic predictions of marine record in response to rising magnitude and frequency of storms.

  20. Sedimentary fabrics of the macrotidal, mud-dominated, inner estuary to fluvio-tidal transition zone, Petitcodiac River estuary, New Brunswick, Canada

    Science.gov (United States)

    Shchepetkina, Alina; Gingras, Murray K.; Zonneveld, John-Paul; Pemberton, S. George

    2016-03-01

    The study provides a detailed description of mud-dominated sedimentary fabrics and their application for the rock record within the inner estuary to the fluvial zone of the Petitcodiac River estuary, New Brunswick, Canada. Sedimentological characteristics and facies distributions of the clay- and silt-rich deposits are reported. The inner estuary is characterized by thick accumulations of interbedded silt and silty clay on intertidal banks that flank the tidally influenced channel. The most common sedimentary structures observed are parallel and wavy lamination, small-scale soft-sediment deformation with microfaults, and clay and silt current ripples. The tidal channel contains sandy silt and clayey silt with planar lamination, massive and convolute bedding. The fluvio-tidal transition zone is represented by interbedded trough cross-stratified sand and gravel beds with planar laminated to massive silty mud. The riverine, non-tidal reach of the estuary is characterized by massive, planar tabular and trough cross-stratified gravel-bed deposits. The absence of bioturbation within the inner estuary to the fluvio-tidal transition zone can be explained by the following factors: low water salinities (0-5 ppt), amplified tide and current speeds, and high concentrations of flocculated material in the water body. Notably, downstream in the middle and outer estuary, bioturbation is seasonally pervasive: in those locales the sedimentary conditions are similar, but salinity is higher. In this study, the sedimentological (i.e., grain size, bedding characters, sedimentary structures) differences between the tidal estuary and the fluvial setting are substantial, and those changes occur over only a few hundred meters. This suggests that the widely used concept of an extensive fluvio-tidal transition zone and its depositional character may not be a geographically significant component of fluvial or estuary deposits, which can go unnoticed in the study of the ancient rocks.

  1. Dynamics of organic and inorganic carbon in surface sediments of the Yellow River Estuary

    Science.gov (United States)

    Yu, Z.; Wang, X.; Liu, X.; Zhang, E.; Hang, F.

    2017-12-01

    Estuarine sediment is an important carbon reservoir thus may play an important role in the global carbon cycle. However, little is known on the dynamics of organic carbon (OC) and inorganic carbon (IC) in the surface sediment of the Yellow River Estuary, a large estuary in northern China. In this study, we applied element analyses and isotopic approach to study spatial distribution and sources of OC and IC in the Yellow River Estuary. We found that TIC concentration (6.3-20.1 g kg-1) was much higher than TOC (0.2-4.4 g kg-1) in the surface sediment. There showed a large spatial variability in TOC and TIC and their stable isotopes. Both TOC and TIC were higher to the north (2.6 and 14.5 g kg-1) than to the south (1.6 and 12.2 g kg-1), except in the southern bay where TOC and TIC reached 2.7 and 15.4 g kg-1, respectively. Generally, TOC and TIC in our study area was mainly autochthonous. The lower TOC values in the south section were due to relatively higher kinetic energy level whereas the higher values in the bay was attributable to terrigenous matters accumulation and lower kinetic energy level. However, the southern bay revealed the most negative δ13Corg and δ13Ccarb, suggesting that there might exist some transfer of OC to IC in the section. Our study points out that the dynamics of sedimentary carbon in the Yellow River Estuary is influenced by multiple and complex processes, and highlights the importance of carbonate in carbon sequstration.

  2. Effect of winds and waves on salt intrusion in the Pearl River estuary

    Directory of Open Access Journals (Sweden)

    W. Gong

    2018-02-01

    Full Text Available Salt intrusion in the Pearl River estuary (PRE is a dynamic process that is influenced by a range of factors and to date, few studies have examined the effects of winds and waves on salt intrusion in the PRE. We investigate these effects using the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST modeling system applied to the PRE. After careful validation, the model is used for a series of diagnostic simulations. It is revealed that the local wind considerably strengthens the salt intrusion by lowering the water level in the eastern part of the estuary and increasing the bottom landward flow. The remote wind increases the water mixing on the continental shelf, elevates the water level on the shelf and in the PRE and pumps saltier shelf water into the estuary by Ekman transport. Enhancement of the salt intrusion is comparable between the remote and local winds. Waves decrease the salt intrusion by increasing the water mixing. Sensitivity analysis shows that the axial down-estuary wind, is most efficient in driving increases in salt intrusion via wind straining effect.

  3. Effect of winds and waves on salt intrusion in the Pearl River estuary

    Science.gov (United States)

    Gong, Wenping; Lin, Zhongyuan; Chen, Yunzhen; Chen, Zhaoyun; Zhang, Heng

    2018-02-01

    Salt intrusion in the Pearl River estuary (PRE) is a dynamic process that is influenced by a range of factors and to date, few studies have examined the effects of winds and waves on salt intrusion in the PRE. We investigate these effects using the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) modeling system applied to the PRE. After careful validation, the model is used for a series of diagnostic simulations. It is revealed that the local wind considerably strengthens the salt intrusion by lowering the water level in the eastern part of the estuary and increasing the bottom landward flow. The remote wind increases the water mixing on the continental shelf, elevates the water level on the shelf and in the PRE and pumps saltier shelf water into the estuary by Ekman transport. Enhancement of the salt intrusion is comparable between the remote and local winds. Waves decrease the salt intrusion by increasing the water mixing. Sensitivity analysis shows that the axial down-estuary wind, is most efficient in driving increases in salt intrusion via wind straining effect.

  4. Carbon Transformations and Source - Sink Dynamics along a River, Marsh, Estuary, Ocean Continuum

    Science.gov (United States)

    Anderson, I. C.; Crosswell, J.; Czapla, K.; Van Dam, B.

    2017-12-01

    Estuaries, the transition zone between land and the coastal ocean, are highly dynamic systems in which carbon sourced from watersheds, marshes, atmosphere, and ocean may be transformed, sequestered, or exported. The net fate of carbon in estuaries, governed by the interactions of biotic and physical drivers varying on spatial and temporal scales, is currently uncertain because of limited observational data. In this study, conducted in a temperate, microtidal, and shallow North Carolina USA estuary, carbon exchanges via river, tributary, and fringing salt marsh, air-water fluxes, sediment C accumulation, and metabolism were monitored over two-years, with sharply different amounts of rainfall. Air-water CO2 fluxes and metabolic variables were simultaneously measured in channel and shoal by conducting high-resolution surveys at dawn, dusk and the following dawn. Marsh CO2 exchanges, sediment C inputs, and lateral exports of DIC and DOC were also measured. Carbon flows between estuary regions and export to the coastal ocean were calculated by quantifying residual transport of DIC and TOC down-estuary as flows were modified by sources, sinks and internal transformations. Variation in metabolic rates, CO2, TOC and DIC exchanges were large when determined for short time and limited spatial scales. However, when scaled to annual and whole estuarine scales, variation tended to decrease because of counteracting metabolic rates and fluxes between channel and shoal or between seasons. Although overall salt marshes accumulated OC, they were a negligible source of DIC and DOC to the estuary, and net inputs of C to the marsh were mainly derived from sediment OC. These results, as observed in other observational studies of estuaries, show that riverine input, light, temperature and metabolism are major controls on carbon cycling. Comparison of our results with other types of estuaries varying in depth, latitude, and nutrification demonstrates large discrepancies underscoring the

  5. Historical Relationships Between Research and Resource Management in the Apalachicola River Estuary.

    Science.gov (United States)

    Livingston, Robert J

    1991-11-01

    A continuous field research effort has been carried out in the Apalachicola River estuary since March 1972. The information generated from this interdisciplinary study has been directly applied to the management of the Apalachicola resource by means of close associations among local, state, and federal officials and university scientists. During the early years, scientific data were instrumental in the prevention of the impoundment of the Apalachicola River. A series of regional studies was carried out to evaluate various forms of effects due to forestry activities, pesticides, and stormwater runoff from urban areas. A review was made of fisheries problems associated with dredging, overfishing, and marine pollution. Results of such studies were directly applied to local management questions. Research that linked the river wetlands with the estuary, in terms of the input of fresh water, nutrients, and organic matter, served as the basis for the purchase of extensive bottomland tracts. Other initiatives were carried out that were designed to protect the naturally high productivity of the river estuary. Further purchases of estuarine wetlands and barrier island properties were made that formed an almost continuous buffer of publicly held lands between upland developments and critical habitats and important populations of the bay system. A regional management plan was adopted that was designed to limit local municipal development in the estuarine region. Analyses of the long-term scientific data indicated that dominant, commercially important estuarine populations are associated with river flow, local salinity characteristics, and biological (predation, competition) interactions with the salinity regime and food web structure. Such interactions are not straight forward, however; they reflect complex interactions of the freshwater influxes and biological response in the estuary that are not well understood. Species-specific responses to the principal driving factors

  6. Turning the tide: effects of river inflow and tidal amplitude on sandy estuaries in laboratory landscape experiments

    Science.gov (United States)

    Kleinhans, Maarten; Braat, Lisanne; Leuven, Jasper; Baar, Anne; van der Vegt, Maarten; van Maarseveen, Marcel; Markies, Henk; Roosendaal, Chris; van Eijk, Arjan

    2016-04-01

    Many estuaries formed over the Holocene through a combination of fluvial and coastal influxes, but how estuary planform shape and size depend on tides, wave climate and river influxes remains unclear. Here we use a novel tidal flume setup of 20 m length by 3 m width, the Metronome (http://www.uu.nl/metronome), to create estuaries and explore a parameter space for the simple initial condition of a straight river in sandy substrate. Tidal currents capable of transporting sediment in both the ebb and flood phase because they are caused by periodic tilting of the flume rather than the classic method of water level fluctuation. Particle imaging velocimetry and a 1D shallow flow model demonstrate that this principle leads to similar sediment mobility as in nature. Ten landscape experiments recorded by timelapse overhead imaging and AGIsoft DEMs of the final bed elevation show that absence of river inflow leads to short tidal basins whereas even a minor discharge leads to long convergent estuaries. Estuary width and length as well as morphological time scale over thousands of tidal cycles strongly depend on tidal current amplitude. Paddle-generated waves subdue the ebb delta causing stronger tidal currents in the basin. Bar length-width ratios in estuaries are slightly larger to those in braided rivers in experiments and nature. Mutually evasive ebb- and flood-dominated channels are ubiquitous and appear to be formed by an instability mechanism with growing bar and bifurcation asymmetry. Future experiments will include mud flats and live vegetation.

  7. Nutrients and carbon fluxes in the estuaries of major rivers flowing into the tropical Atlantic

    Directory of Open Access Journals (Sweden)

    Moacyr Cunha De Araujo

    2014-05-01

    Full Text Available Knowledge of the seasonal variability of river discharge and the concentration of nutrients in the estuary waters of large rivers flowing into the tropical Atlantic contributes to a better understanding of the biogeochemical processes that occur in adjacent coastal and ocean systems. The monthly averaged variations of the physical and biogeochemical contributions of the Orinoco, Amazon, São Francisco, Paraíba do Sul (South America, Volta, Niger and Congo (Africa Rivers are estimated from models or observations. The results indicate that these rivers deliver approximately 0.1 Pg C yr-1 in its dissolved organic (DOC 0.046 Pg C yr-1 and inorganic (DIC 0.053 Pg C yr-1 forms combined. These values represent 27.3% of the global DOC and 13.2% of the global DIC delivered by rivers into the world’s oceans. Estimations of the air-sea CO2 fluxes indicate a slightly higher atmospheric liberation for the African systems compared with the South American estuaries (+10.67 mmol m-2 day-1 and +5.48 mmol m-2 day-1, respectively. During the high river discharge periods, the fluxes remained positive in all of the analyzed systems (average +128 mmol m-2 day-1, except at the mouth of the Orinoco River, which continued to act as a sink for CO2. During the periods of low river discharges, the mean CO2 efflux decreased to +5.29 mmol m-2 day-1. The updated and detailed review presented here contributes to the accurate quantification of CO2 input into the atmosphere and to ongoing studies on the oceanic modeling of biogeochemical cycles in the tropical Atlantic.

  8. Mapping ecosystem services in the St. Louis River Estuary

    Science.gov (United States)

    Sustainable management of ecosystems for the perpetual flow of services beneficial to human communities requires reliable data about from where in the ecosystem services flow. Our objective is to map ecosystem services in the St. Louis River with the overarching U.S. EPA goal of ...

  9. Mapping ecosystem services in the St. Louis River estuary (presentation)

    Science.gov (United States)

    Management of ecosystems for sustainable provision of services beneficial to human communities requires reliable data about from where in the ecosystem services flow. Our objective is to map ecosystem services in the St. Louis River with the overarching EPA goal of community sust...

  10. Effects of dams on downstream molluscan predator-prey interactions in the Colorado River estuary.

    Science.gov (United States)

    Smith, Jansen A; Handley, John C; Dietl, Gregory P

    2018-05-30

    River systems worldwide have been modified for human use and the downstream ecological consequences are often poorly understood. In the Colorado River estuary, where upstream water diversions have limited freshwater input during the last century, mollusc remains from the last several hundred years suggest widespread ecological change. The once abundant clam Mulinia modesta has undergone population declines of approximately 94% and populations of predators relying on this species as a food source have probably declined, switched to alternative prey species or both. We distinguish between the first two hypotheses using a null model of predation preference to test whether M. modesta was preyed upon selectively by the naticid snail, Neverita reclusiana , along the estuary's past salinity gradient. To evaluate the third hypothesis, we estimate available prey biomass today and in the past, assuming prey were a limiting resource. Data on the frequency of drill holes-identifiable traces of naticid predation on prey shells-showed several species, including M. modesta , were preferred prey. Neverita reclusiana was probably able to switch prey. Available prey biomass also declined, suggesting the N. reclusiana population probably also declined. These results indicate a substantial change to the structure of the benthic food web. Given the global scale of water management, such changes have probably also occurred in many of the world's estuaries. © 2018 The Author(s).

  11. Variation of phytoplankton community structure from the Pearl River estuary to South China Sea.

    Science.gov (United States)

    Jiang, Zhao-Yu; Wang, You-Shao; Cheng, Hao; Sun, Cui-Ci; Wu, Mei-Lin

    2015-10-01

    The Pearl River is located in the northern part of South China Sea. The environment of the Pearl River estuary (PRE) is significantly impacted by nutrients from anthropogenic activities. Along the anthropogenic pollution gradient from the PRE to South China Sea, the phylogenetic diversity and biomass of phytoplankton was examined in relation to physic-chemical variables. The richness of rbcL gene was higher in the open sea than the estuary, while the concentration of chlorophyll a (Chl a) was higher in the estuary than in the open sea. The cluster analysis of the sequences data resulted in seven phytoplankton community types and the dominant species of phytoplankton changed from Cryptophytes and Diatoms to Prymnesiophytes and Diatoms along the gradient. The community structure of phytoplankton was shaped by nutrients and salinity. The phytoplankton biomass was significantly positively affected by phosphorus, nitrite and ammonium (P < 0.01) but negatively by salinity (P < 0.05); the phytoplankton diversity was highly positively affected by salinity (P < 0.05) but negatively by silicate and nitrate (P < 0.01; P < 0.05, respectively). Anthropogenic activities played a critical role in the phytoplankton distribution and biomass of the study area. Further research is necessary to reveal the influence mechanism of environmental factors on the phytoplankton.

  12. Sediment accumulation rate and radiological characterisation of the sediment of Palmones River estuary (southern of Spain)

    International Nuclear Information System (INIS)

    Rubio, L.; Linares-Rueda, A.; Duenas, C.; Fernandez, M.C.; Clavero, V.; Niell, F.X.; Fernandez, J.A.

    2003-01-01

    Chemical analyses and radioecological methods were combined in order to estimate the sediment accumulation rate in the upper 20 cm depth of the Palmones River estuary. Organic matter, total carbon, C:N and 137 Cs vertical profiles showed changes at 13 cm depth. These changes could be associated with the decrease in river input since 1987 when a dam situated in the upper part of the estuary started to store water. Using 1987 as reference to date the sediment, accumulation rate was 1.2 cm yr -1 . As alternative method, two layer model of 210 Pb xs vertical distribution showed a sedimentation rate of 0.7 cm yr -1 with a surface mixing layer of 7 cm thickness. The high ammonium, potassium and sodium content in pore water and the strong correlation between 137 Cs activities and organic matter in dry sediment suggests that 137 Cs (the only anthropogenic product detected) is mainly accumulated in the estuary associated with the particulate organic material from the catchment area

  13. Effects of Spartina alterniflora Invasion on Soil Respiration in the Yangtze River Estuary, China

    Science.gov (United States)

    Bu, Naishun; Qu, Junfeng; Li, Zhaolei; Li, Gang; Zhao, Hua; Zhao, Bin; Li, Bo; Chen, Jiakuan; Fang, Changming

    2015-01-01

    Many studies have found that plant invasion can enhance soil organic carbon (SOC) pools, by increasing net primary production (NPP) and/or decreased soil respiration. While most studies have focused on C input, little attention has been paid to plant invasion effects on soil respiration, especially in wetland ecosystems. Our study examined the effects of Spartina alterniflora invasion on soil respiration and C dynamics in the Yangtze River estuary. The estuary was originally occupied by two native plant species: Phragmites australis in the high tide zone and Scirpus mariqueter in the low tide zone. Mean soil respiration rates were 185.8 and 142.3 mg CO2 m−2 h−1 in S. alterniflora and P. australis stands in the high tide zone, and 159.7 and 112.0 mg CO2 m−2 h−1 in S. alterniflora and S. mariqueter stands in the low tide zone, respectively. Aboveground NPP (ANPP), SOC, and microbial biomass were also significantly higher in the S. alterniflora stands than in the two native plant stands. S. alterniflora invasion did not significantly change soil inorganic carbon or pH. Our results indicated that enhanced ANPP by S. alterniflora exceeded invasion-induced C loss through soil respiration. This suggests that S. alterniflora invasion into the Yangtze River estuary could strengthen the net C sink of wetlands in the context of global climate change. PMID:25799512

  14. Effects of Spartina alterniflora invasion on soil respiration in the Yangtze River estuary, China.

    Science.gov (United States)

    Bu, Naishun; Qu, Junfeng; Li, Zhaolei; Li, Gang; Zhao, Hua; Zhao, Bin; Li, Bo; Chen, Jiakuan; Fang, Changming

    2015-01-01

    Many studies have found that plant invasion can enhance soil organic carbon (SOC) pools, by increasing net primary production (NPP) and/or decreased soil respiration. While most studies have focused on C input, little attention has been paid to plant invasion effects on soil respiration, especially in wetland ecosystems. Our study examined the effects of Spartina alterniflora invasion on soil respiration and C dynamics in the Yangtze River estuary. The estuary was originally occupied by two native plant species: Phragmites australis in the high tide zone and Scirpus mariqueter in the low tide zone. Mean soil respiration rates were 185.8 and 142.3 mg CO2 m(-2) h(-1) in S. alterniflora and P. australis stands in the high tide zone, and 159.7 and 112.0 mg CO2 m(-2) h(-1) in S. alterniflora and S. mariqueter stands in the low tide zone, respectively. Aboveground NPP (ANPP), SOC, and microbial biomass were also significantly higher in the S. alterniflora stands than in the two native plant stands. S. alterniflora invasion did not significantly change soil inorganic carbon or pH. Our results indicated that enhanced ANPP by S. alterniflora exceeded invasion-induced C loss through soil respiration. This suggests that S. alterniflora invasion into the Yangtze River estuary could strengthen the net C sink of wetlands in the context of global climate change.

  15. Effects of Spartina alterniflora invasion on soil respiration in the Yangtze River estuary, China.

    Directory of Open Access Journals (Sweden)

    Naishun Bu

    Full Text Available Many studies have found that plant invasion can enhance soil organic carbon (SOC pools, by increasing net primary production (NPP and/or decreased soil respiration. While most studies have focused on C input, little attention has been paid to plant invasion effects on soil respiration, especially in wetland ecosystems. Our study examined the effects of Spartina alterniflora invasion on soil respiration and C dynamics in the Yangtze River estuary. The estuary was originally occupied by two native plant species: Phragmites australis in the high tide zone and Scirpus mariqueter in the low tide zone. Mean soil respiration rates were 185.8 and 142.3 mg CO2 m(-2 h(-1 in S. alterniflora and P. australis stands in the high tide zone, and 159.7 and 112.0 mg CO2 m(-2 h(-1 in S. alterniflora and S. mariqueter stands in the low tide zone, respectively. Aboveground NPP (ANPP, SOC, and microbial biomass were also significantly higher in the S. alterniflora stands than in the two native plant stands. S. alterniflora invasion did not significantly change soil inorganic carbon or pH. Our results indicated that enhanced ANPP by S. alterniflora exceeded invasion-induced C loss through soil respiration. This suggests that S. alterniflora invasion into the Yangtze River estuary could strengthen the net C sink of wetlands in the context of global climate change.

  16. Disposal of radioactive wastes into rivers, lakes and estuaries

    International Nuclear Information System (INIS)

    1971-01-01

    The purpose of this report is to present, in the light of the information and experience accumulated to date, those principles and practices which, if applied to the disposal of radioactive wastes into inland surface and estuarial waters will ensure that man will not experience radiation exposures that are above the limits recommended by the International Commission for Radiation Protection (ICRP); and further, that radiation exposures are kept as far below those limits as is practicable. Disposal into sub-surface waters has not been specifically considered as this topic has been covered in another International Atomic Energy Agency publication. The report discusses the mechanisms and parameters which affect and control the fate of radionuclides introduced into fresh waters; it discusses the concepts of ''critical nuclide'', ''critical pathway'' and ''critical population group'' and demonstrates how the use of these concepts provides a sound, convenient and economical means for setting discharge limits and maintaining a continuing surveillance. It offers practical advice on the use of these concepts; gives some detailed information on uptake and dispersion mechanisms; and offers instruction on how to use this information and these concepts to estimate potential radiation doses and thus establish discharge limits.

  17. Mathematical modelling for distribution of heavy metals in estuary area of Red River (Vietnam)

    Science.gov (United States)

    Nguyen, N. T. T.; Volkova, I. V.

    2018-05-01

    In this paper, the authors studied the features of spatial distribution of some heavy metals (Pb, Hg, As) in the system “suspended substance - bottom sediments” in the mouth area of the Red River (Vietnam). A mathematical modelling for diffusion processes of heavy metals in a suspended form, in bottom sediments and the spatial analysis for the results of these models were proposed and implemented. The studies were carried out during main hydrological seasons of 2014 - 2016 (during the flood and inter-natal periods). The propagation of heavy metals was modeled by solving the equation of turbulent diffusion. A spatial analysis of the content of heavy metals in the suspended form and in the bottom sediments was implemented by using the interpolation model in ArcGIS 10.2.2. The distribution of Pb, Hg, As concentration of the suspended form and bottom sediment phases in the estuary area of the Red River was characterized by maximum in the mouths of the branches and general decreasing gradient towards the sea. Maximum concentrations of Pb, Hg in suspended forms were observed in the surface layer of water at the river-sea barrier. The content of Hg and As in the estuary region of the Red River was observed in the following order: SSsurfBS.

  18. Association of plutonium with sediments from the Ob and Yenisey Rivers and Estuaries

    International Nuclear Information System (INIS)

    Skipperud, Lindis; Brown, Justin; Fifield, L. Keith; Oughton, Deborah H.; Salbu, Brit

    2009-01-01

    The present study applied sequential extraction techniques to investigate the binding and mobility of plutonium (Pu) in sediments from the rivers and estuaries of the Ob and Yenisey. As a study site, the Ob and Yenisey are particularly interesting as both rivers have weapons-grade Pu sources in their catchment areas, including the Russian Pu production and reprocessing plants at Mayak, Tomsk-7 and Krashnoyarsk, and the Semipalantinsk nuclear weapons testing site in Kazakhstan. Plutonium activity and 240 Pu/ 239 Pu ratios were determined using accelerator mass spectrometry (AMS). Sequential extractions showed that between 47 and 80% of the Pu in Yenisey River sediments and 35-53% of the Pu in soils around the Techa River are mobilized with weak oxidising agents, which can indicate that Pu is bound to organic material. In contrast, Pu in Ob and Yenisey Estuarine sediments was more strongly bound, with 60-100% being found in the HNO 3 -extractable fraction. This change in speciation could reflect either that Pu bound to organic material in the Techa and Yenisey River sediments becomes more fixed to the sediments with time, or that organic-bound Pu is mobilized and released to the water when the sediments encounter the more saline water of the Ob and Yenisey estuaries. In general, 240 Pu/ 239 Pu ratios were relatively consistent between different extraction fractions, although, in whole sediments, an increase in ratio was observed with distance from the source. This reflects the increased influence of weapon fallout from catchment runoff within the river systems, as compared to the weapons-grade sources close to the production and reprocessing plants. Knowledge of Pu speciation in the Ob and Yenisey Rivers, and the processes controlling its behaviour in estuarine systems, can improve predictions of its transfer and subsequent environmental impact to Arctic Seas

  19. An assessment of natural radionuclides in water of Langat River estuary, Selangor

    Energy Technology Data Exchange (ETDEWEB)

    Hamzah, Zaini, E-mail: tengkuliana88@gmail.com; Rosli, Tengku Nurliana Tuan Mohd, E-mail: tengkuliana88@gmail.com; Saat, Ahmad, E-mail: tengkuliana88@gmail.com; Wood, Ab. Khalik, E-mail: tengkuliana88@gmail.com [Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia)

    2014-02-12

    An estuary is an area that has a free connection with the open sea and it is a dynamic semi-enclosed coastal bodies. Ex-mining, aquaculture and industrial areas in Selangor are the sources of pollutants discharged into the estuary water. Radionuclides are considered as pollutants to the estuary water. Gamma radiations emitted by natural radionuclides through their decaying process may give impact to human. The radiological effect of natural radionuclides which are {sup 226}Ra, {sup 228}Ra, {sup 40}K, {sup 238}U and {sup 232}Th, were explored by determining the respective activity concentrations in filtered water along the Langat estuary, Selangor. Meanwhile, in- situ water quality parameters such as temperature, dissolve oxygen (DO), salinity, total suspended solid (TSS), pH and turbidity were measured by using YSI portable multi probes meter. The activity concentration of {sup 226}Ra, {sup 228}Ra and {sup 40}K were determined by using gamma-ray spectrometry with high-purity germanium (HPGe) detector. The activity concentrations of {sup 226}Ra, {sup 228}Ra and {sup 40}K in samples are in the range of 0.17 - 0.67 Bq/L, 0.16 - 0.97 Bq/L and 1.22 - 5.57 Bq/L respectively. On the other hand, the concentrations of uranium-238 and thorium-232 were determined by using Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF). The thorium concentrations are between 0.17 ppm to 0.28 ppm and uranium concentrations were 0.25 ppm to 0.31 ppm. The results show activity concentrations of radionuclides are slightly high near the river estuary. The Radium Equivalent, Absorbed Dose Rate, External Hazard Index, and Annual Effective Dose of {sup 226}Ra, {sup 228}Ra and {sup 40}K are also studied.

  20. A Coupled Model of the 1D River Network and 3D Estuary Based on Hydrodynamics and Suspended Sediment Simulation

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2014-01-01

    Full Text Available River networks and estuaries are very common in coastal areas. Runoff from the upper stream interacts with tidal current from open sea in these two systems, leading to a complex hydrodynamics process. Therefore, it is necessary to consider the two systems as a whole to study the flow and suspended sediment transport. Firstly, a 1D model is established in the Pearl River network and a 3D model is applied in its estuary. As sufficient mass exchanges between the river network and its estuary, a strict mathematical relationship of water level at the interfaces can be adopted to couple the 1D model with the 3D model. By doing so, the coupled model does not need to have common nested grids. The river network exchanges the suspended sediment with its estuary by adding the continuity conditions at the interfaces. The coupled model is, respectively, calibrated in the dry season and the wet season. The results demonstrate that the coupled model works excellently in simulating water level and discharge. Although there are more errors in simulating suspended sediment concentration due to some reasons, the coupled model is still good enough to evaluate the suspended sediment transport in river network and estuary systems.

  1. Antibiotics in riverine runoff of the Pearl River Delta and Pearl River Estuary, China: Concentrations, mass loading and ecological risks

    International Nuclear Information System (INIS)

    Xu, Weihai; Yan, Wen; Li, Xiangdong; Zou, Yongde; Chen, Xiaoxiang; Huang, Weixia; Miao, Li; Zhang, Ruijie; Zhang, Gan; Zou, Shichun

    2013-01-01

    Ten antibiotics belonging to three groups (macrolides, fluoroquinolones and sulfonamides) were investigated in riverine runoff of the Pearl River Delta (PRD) and Pearl River Estuary (PRE), South China for assessing the importance of riverine runoff in the transportation of contaminants from terrestrial sources to the open ocean. All antibiotics were detected in the eight outlets with concentrations ranging from 0.7 to 127 ng L −1 . The annual mass loadings of antibiotics from the PRD to the PRE and coast were 193 tons with 102 tons from the fluoroquinolone group. It showed that antibiotics decreased from the riverine outlets to the PRE and open ocean. Risk assessment showed that most of these antibiotics showed various ecological risks to the relevant aquatic organisms, in which ofloxacin (OFL), erythromycin (ETM) and ciprofloxacin (CIP) posed high ecological risks to the studied aquatic environments. -- Highlights: •Antibiotics were ubiquitous in the river water and costal water in the Pearl River Delta. •Antibiotics exhibited distinct temporal and spatial trends in the riverine runoff outlets. •Annual outflows of antibiotics were 193 tons from the Pearl River to coastal ocean. •Some antibiotics posed high risks to some organisms in the PRD environments. -- Antibiotics were ubiquitous in the river and coastal water in the Pearl River Delta and posed various ecological risks to the relevant aquatic organisms

  2. The morphology and morphodynamics of sand-gravel subaquatic dunes: the Raba River estuary, Poland

    Directory of Open Access Journals (Sweden)

    Artur RADECKI-PAWLIK

    2012-08-01

    Full Text Available In the outlet of the Raba River to the Vistula, the biggest river in Poland, the morphology and morphodynamics of sand and fine-gravel subaquatic dunes were investigated. The site is situated in highland region just about the entrance to Polish Carpathians. The dunes formed on the Raba River bed estuary are composed of sand and fine gravel (d50 up to 11 mm. Systematic observation (within the 2000-2005 were made of geometry, sediment composition and hydraulic climate under which the dunes grew and decomposed. The investigation focuses here mostly on the geometrical parameters of these bed forms such as height, length, as well as granulometric characteristics of the sediment. Based on in-site measurements different hydraulic parameters were calculated such as shear stresses, resistant coefficient, Froude and Reynolds numbers and roughness coefficient. It was found that the relation between height (H and length (L of the Raba estuary dunes describes the formula: H = 0.05L0.35. Also these dunes are steeper and flatter then classical H/L index is: H/L = 0.0518L0.622. During the field campaign, when the foot access to the estuary was possible and dunes were spotted on the river bed the range of measured water velocity was from v = 0.39 m∙s-1 to v = 0.81 m∙s-1 with the highest velocity over the dune crest. At the same time the measured range of shear stresses within the dune field formation were from t = 0.115 N×m-2 to t = 1.59 N×m-2. On the field investigations the CCHE2D - two-dimensional unsteady flow and sediment transport model for non-equilibrium transport of non-uniform sediment mixtures – was applied. The model was used to simulate the morphodynamic changes along the outlet of the Raba River basing on field observations of the 2005 summer flood as well as calculate hydraulics parameters. It was also used to test and confirm the range of morphodynamic changes, which take place along the research reach where the dunes are being developed

  3. Use of multitracers for the study of water mixing in the Paraiba do Sul River estuary

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Thaisa Abreu, E-mail: abreu.thaisa@gmail.co [Departamento de Quimica, Pontificia Universidade Catolica, 22453-900 Rio de Janeiro, RJ (Brazil); Godoy, Jose Marcus [Departamento de Quimica, Pontificia Universidade Catolica, 22453-900 Rio de Janeiro, RJ (Brazil); Instituto de Radioprotecao e Dosimetria IRD/CNEN, 22780-160 Rio de Janeiro, RJ (Brazil); Godoy, Maria Luiza D.P. [Instituto de Radioprotecao e Dosimetria IRD/CNEN, 22780-160 Rio de Janeiro, RJ (Brazil); Moreira, Isabel [Departamento de Quimica, Pontificia Universidade Catolica, 22453-900 Rio de Janeiro, RJ (Brazil); Carvalho, Zenildo L. [Instituto de Radioprotecao e Dosimetria IRD/CNEN, 22780-160 Rio de Janeiro, RJ (Brazil); Salomao, Marcos Sarmet M.B.; Rezende, Carlos E. [Centro de Biociencias e Biotecnologia, Universidade Estadual do Norte Fluminense, 28013-600 Campos dos Goytacazes, RJ (Brazil)

    2010-07-15

    Multitracers were used to study water mixing in the Paraiba do Sul River estuary region in August 2007 (dry season) and March 2008 (rainy season) and to evaluate the reach of the river plume in the direction of the open ocean. Two sampling campaigns were carried out, each in a different season. Based on these results, it was possible to conclude that the multitracers used in this study (salinity, Si, Ba and U, as well as the radium isotopes {sup 223}Ra, {sup 224}Ra, {sup 226}Ra and {sup 228}Ra) presented satisfactory results toward defining the plume reach and determining the residence time and water-mixing processes in the estuary. A strong correlation was observed between tracers and the distance to the coast. During the low river water discharge period, the riverine water took about 10 days to reach open ocean waters (salinity {approx} 35). During the rainy period this value decreased to 6 days. Based on the radium results, it was possible to calculate diffusion coefficients (K{sub h}) of 23 km{sup 2} d{sup -1} and 38 km{sup 2} d{sup -1} for {sup 224}Ra and {sup 223}Ra, respectively, during the dry season (winter). Values of 65 km{sup 2} d{sup -1} and 68 km{sup 2} d{sup -1} for {sup 223}Ra and {sup 224}Ra, respectively, were found for the rainy period (summer).

  4. Use of multitracers for the study of water mixing in the Paraiba do Sul River estuary

    International Nuclear Information System (INIS)

    Souza, Thaisa Abreu; Godoy, Jose Marcus; Godoy, Maria Luiza D.P.; Moreira, Isabel; Carvalho, Zenildo L.; Salomao, Marcos Sarmet M.B.; Rezende, Carlos E.

    2010-01-01

    Multitracers were used to study water mixing in the Paraiba do Sul River estuary region in August 2007 (dry season) and March 2008 (rainy season) and to evaluate the reach of the river plume in the direction of the open ocean. Two sampling campaigns were carried out, each in a different season. Based on these results, it was possible to conclude that the multitracers used in this study (salinity, Si, Ba and U, as well as the radium isotopes 223 Ra, 224 Ra, 226 Ra and 228 Ra) presented satisfactory results toward defining the plume reach and determining the residence time and water-mixing processes in the estuary. A strong correlation was observed between tracers and the distance to the coast. During the low river water discharge period, the riverine water took about 10 days to reach open ocean waters (salinity ∼ 35). During the rainy period this value decreased to 6 days. Based on the radium results, it was possible to calculate diffusion coefficients (K h ) of 23 km 2 d -1 and 38 km 2 d -1 for 224 Ra and 223 Ra, respectively, during the dry season (winter). Values of 65 km 2 d -1 and 68 km 2 d -1 for 223 Ra and 224 Ra, respectively, were found for the rainy period (summer).

  5. Fate of polybrominated diphenyl ethers in the environment of the Pearl River Estuary, South China

    International Nuclear Information System (INIS)

    Guan Yufeng; Sojinu, O.S. Samuel; Li Shaomeng; Zeng, Eddy Y.

    2009-01-01

    Ninety-six riverine runoff samples collected at eight major outlets in the Pearl River Delta (PRD), South China, during 2005-2006 were analyzed for 17 brominated diphenyl ether (BDE) congeners (defined as Σ 17 PBDE). Fourteen and 15 congeners were detected, respectively, in the dissolved and particulate phases. These data were further used to elucidate the partitioning behavior of BDE congeners in riverine runoff. Several related fate processes, i.e. air-water exchange, dry and wet deposition, degradation, and sedimentation, within the Pearl River Estuary (PRE), were examined to estimate the inputs of Σ 10 PBDE (sum of the target BDE congeners, BDE-28, -47, -66, -85, -99, -100, -138, -153, -154, and -183) and BDE-209 from the PRD to the coastal ocean based on mass balance considerations. The results showed that annual outflows of Σ 10 PBDE and BDE-209 were estimated at 126 and 940 kg/year, respectively from the PRE to coastal ocean. Besides sedimentation and degradation, the majority of Σ 10 PBDE and BDE-209 discharged into the PRE via riverine runoff was transported to the coastal ocean. - Fate of polybrominated diphenyl ethers in the environment the Pearl River Estuary, South China.

  6. Nitrogen Source Apportionment for the Catchment, Estuary, and Adjacent Coastal Waters of the River Scheldt

    Directory of Open Access Journals (Sweden)

    Jan E. Vermaat

    2012-06-01

    Full Text Available Using the systems approach framework (SAF, a coupled model suite was developed for simulating land-use decision making in response to nutrient abatement costs and water and nutrient fluxes in the hydrological network of the Scheldt River, and nutrient fluxes in the estuary and adjacent coastal sea. The purpose was to assess the efficiency of different long-term water quality improvement measures in current and future climate and societal settings, targeting nitrogen (N load reduction. The spatial-dynamic model suite consists of two dynamically linked modules: PCRaster is used for the drainage network and is combined with ExtendSim modules for farming decision making and estuarine N dispersal. Model predictions of annual mean flow and total N concentrations compared well with data available for river and estuary (r² ≥ 0.83. Source apportionment was carried out to societal sectors and administrative regions; both households and agriculture are the major sources of N, with the regions of Flanders and Wallonia contributing most. Load reductions by different measures implemented in the model were comparable (~75% remaining after 30 yr, but costs differed greatly. Increasing domestic sewage connectivity was more effective, at comparatively low cost (47% remaining. The two climate scenarios did not lead to major differences in load compared with the business-as-usual scenario (~88% remaining. Thus, this spatially explicit model of water flow and N fluxes in the Scheldt catchment can be used to compare different long-term policy options for N load reduction to river, estuary, and receiving sea in terms of their effectiveness, cost, and optimal location of implementation.

  7. Evaluation of distribution and sources of sewage molecular marker (LABs) in selected rivers and estuaries of Peninsular Malaysia.

    Science.gov (United States)

    Magam, Sami M; Zakaria, Mohamad Pauzi; Halimoon, Normala; Aris, Ahmad Zaharin; Kannan, Narayanan; Masood, Najat; Mustafa, Shuhaimi; Alkhadher, Sadeq; Keshavarzifard, Mehrzad; Vaezzadeh, Vahab; Sani, Muhamad S A; Latif, Mohd Talib

    2016-03-01

    This is the first extensive report on linear alkylbenzenes (LABs) as sewage molecular markers in surface sediments collected from the Perlis, Kedah, Merbok, Prai, and Perak Rivers and Estuaries in the west of Peninsular Malaysia. Sediment samples were extracted, fractionated, and analyzed using gas chromatography mass spectrometry (GC-MS). The concentrations of total LABs ranged from 68 to 154 (Perlis River), 103 to 314 (Kedah River), 242 to 1062 (Merbok River), 1985 to 2910 (Prai River), and 217 to 329 ng g(-1) (Perak River) dry weight (dw). The highest levels of LABs were found at PI3 (Prai Estuary) due to the rapid industrialization and population growth in this region, while the lowest concentrations of LABs were found at PS1 (upstream of Perlis River). The LABs ratio of internal to external isomers (I/E) in this study ranged from 0.56 at KH1 (upstream of Kedah River) to 1.35 at MK3 (Merbok Estuary) indicating that the rivers receive raw sewage and primary treatment effluents in the study area. In general, the results of this paper highlighted the necessity of continuation of water treatment system improvement in Malaysia.

  8. Assessment of water quality of a river-dominated estuary with hydrochemical parameters: A statistical approach.

    Digital Repository Service at National Institute of Oceanography (India)

    Padma, P.; Sheela, V.S.; Suryakumari, S.; Jayalakshmy, K.V.; Nair, S.M.; Kumar, N.C.

    stream_size 64084 stream_content_type text/plain stream_name Water_Qual_Expos_Health_5_197.pdf.txt stream_source_info Water_Qual_Expos_Health_5_197.pdf.txt Content-Encoding UTF-8 Content-Type text/plain; charset=UTF-8... Water Qual Expo Health DOI 10.1007/s12403-014-0115-9 ORIGINAL PAPER Assessment of Water Quality of a River-Dominated Estuary with Hydrochemical Parameters: A Statistical Approach P. Padma · V. S. Sheela · S. Suryakumari · K. V. Jayalakshmy · S. M. Nair...

  9. Some ecological studies of the lower Cape Fear River Estuary, ocean outfall, and Dutchman Creek, 1971

    International Nuclear Information System (INIS)

    Copeland, B.J.; Birkhead, W.S.

    1972-01-01

    A survey of the hydrography and biological components of the Cape Fear River Estuary and nearshore ocean off Oak Island was conducted. Species diversity indices were computed from nekton samples and phytoplankton, zooplankton, and benthos samples are being analysed. A computer program was developed whereby data were alphabetized by species, sorted by location, station, and date, and printed. Experiments were conducted to determine the Critical Thermal Maximum of shrimp. Measurements were made on water temperature, salinity, and dissolved oxygen from June through October. (U.S.)

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

    Science.gov (United States)

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

    2010-05-01

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

  11. Multivariate statistical study of heavy metal enrichment in sediments of the Pearl River Estuary

    International Nuclear Information System (INIS)

    Liu, W.X.; Li, X.D.; Shen, Z.G.; Wang, D.C.; Wai, O.W.H.; Li, Y.S.

    2003-01-01

    Multivariate statistical analysis identified the heavy metal accumulation layers of sediment profiles and showed the various sources of metals in the estuary. - The concentrations and chemical partitioning of heavy metals in the sediment cores of the Pearl River Estuary were studied. Based on Pearson correlation coefficients and principal component analysis results, Al was selected as the concentration normalizer for Pb, while Fe was used as the normalizing element for Co, Cu, Ni and Zn. In each profile, sections with metal concentrations exceeding the upper 95% prediction interval of the linear regression model were regarded as metal enrichment layers. The heavy metal accumulation mainly occurred at sites in the western shallow water areas and east channel, which reflected the hydraulic conditions and influence from riparian anthropogenic activities. Heavy metals in the enrichment sections were evaluated by a sequential extraction method for possible chemical forms in sediments. Since the residual, Fe/Mn oxides and organic/sulfide fractions were dominant geochemical phases in the enriched sections, the bioavailability of heavy metals in sediments was generally low. The 206 Pb/ 207 Pb ratios in the metal-enriched sediment sections also revealed the influence of anthropogenic sources. The spatial distribution of cumulative heavy metals in the sediments suggested that the Zn and Cu mainly originated from point sources, while the Pb probably came from non-point sources in the estuary

  12. Microplastics in oysters Saccostrea cucullata along the Pearl River Estuary, China.

    Science.gov (United States)

    Li, Heng-Xiang; Ma, Li-Sha; Lin, Lang; Ni, Zhi-Xin; Xu, Xiang-Rong; Shi, Hua-Hong; Yan, Yan; Zheng, Guang-Ming; Rittschof, Daniel

    2018-05-01

    As a transitional zone between riverine and marine environments, an estuary plays an important role for the sources, accumulation and transport of microplastics. Although estuarine environments are hotspots of microplastic pollution, the correlation between microplastic pollution and aquatic organisms is less known. Here we investigated microplastic pollution in wild oysters Saccostrea cucullata from 11 sampling sites along the Pearl River Estuary in South China. The microplastic abundances in oysters ranged from 1.4 to 7.0 items per individual or from 1.5 to 7.2 items per gram tissue wet weight, which were positively related to those in surrounding waters. The oysters near urban areas contained significantly more microplastics than those near rural areas. Fibers accounted for 69.4% of the total microplastics in oysters. Microplastic sizes varied from 20 to 5000 μm and 83.9% of which were less than 100 μm. Light color microplastics were significantly more common than dark color ones. Based on the results, oysters are recommended as a biomonitor for the microplastic pollution in estuaries. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Mixing behavior of chromophoric dissolved organic matter in the Pearl River Estuary in spring

    Science.gov (United States)

    Lei, Xia; Pan, Jiayi; Devlin, Adam T.

    2018-02-01

    Mixing behavior of chromophoric dissolved organic matter (CDOM) in the Pearl River Estuary (PRE) and relevant hydrodynamic parameters such as horizontal transport and vertical mixing are identified and discussed based on a set of sampling data obtained during a cruise in May 2014. Using a theoretical conservative mixing model, the surface CDOM in the PRE in spring is classified into two groups by the CDOM absorption-spectral slope relationship (a(300) vs S(275-295)): First, terrigenous CDOM under a non-conservative mixing condition, and removal processes such as photobleaching are suggested to happen; second, marine CDOM behaves conservatively during mixing. The mixing of CDOM at the bottom is shown to be conservative. Controlled by the two-layer gravitational circulation in the PRE, the northern and western estuary shows higher CDOM absorption and lower spectral slope than the southern and eastern estuary, and the surface CDOM presents higher absorption and lower spectral slope than the bottom. Horizontal transport is hypothesized to be the dominant hydrodynamic mechanism affecting CDOM variation and mixing behavior in the PRE, while the vertical mixing has less influence.

  14. PPCPs in Jiulong River estuary (China): Spatiotemporal distributions, fate, and their use as chemical markers of wastewater.

    Science.gov (United States)

    Sun, Qian; Li, Yan; Li, Mingyue; Ashfaq, Muhammad; Lv, Min; Wang, Hongjie; Hu, Anyi; Yu, Chang-Ping

    2016-05-01

    The occurrence and fate of 50 pharmaceuticals and personal care products (PPCPs) were investigated in the surface water of Jiulong River estuary in the southeast of China in spring, wet season, summer, autumn and winter. Results demonstrated a wide distribution of PPCPs in Jiulong River estuary, where 34 PPCPs were detected at least once and 5 PPCPs were detected in all the samples, including caffeine, diclofenac, metoprolol, methyl paraben, and propyl paraben. Spatial and seasonal variations were observed. Special emphasis was placed on the PPCP fate in the estuary. Most PPCPs showed a non-conservative behavior in the estuary, while the non-steroidal anti-inflammatory drugs and bisphenol A showed a pseudo-conservative behavior. The non-conservative and pseudo-conservative behavior was attributed to the combination of the seawater dilution, the introduction of PPCPs via the sewage water, and the physical, chemical, or biological removal processes. Furthermore, PPCP concentrations showed drastic variations in the turbidity maximum zones. To our best knowledge, this is the first work to indicate the pseudo-conservative behavior of PPCPs in the estuary, and to show the drastic variations of PPCPs in the turbidity maximum zone. In addition, the ratio of labile to conservative PPCPs was calculated to track the source of untreated sewage contamination. Results showed a significantly higher ratio compared to the average value in WWTP effluents, indicating the ubiquitous discharge of untreated domestic wastewater in Jiulong River estuary. In addition, the high ratio of bisphenol A to conservative PPCPs implied the potential input of untreated industrial wastewater in Jiulong River estuary. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Analysis of thermal impact in tidal rivers and estuaries

    International Nuclear Information System (INIS)

    Haeuser, J.; Eppel, D.; Tanzer, F.

    1980-01-01

    The paper presents a far field mathematical model for numerical simulation of transient one or two-dimensional thermal distributions in regions with severe reversing flow conditions. The Eulerian formulation employs the integral form of the conservation principles for mass and thermal energy. The two-dimensional (2 D) solution area is spanned by discrete elements of variable size and shape. The three-dimensional geometry of the flow region is accounted for by spatially intergrating over the enclosure surfaces of the discrete element. The derivation of the two-dimensional depth-averaged temperatur equations includes the constributions of the vertical variations of velocity and temperature. Surface heat transfer as well as turbulent effects are taken into account. Important mathematical and computational features of the model are summarized. There is a discussion of the four main algorithms, necessary to treat flow regions with complex shoreline geometries, viz. (i) specification of the boundary (ii) determination of all discrete element midpoints lying within the (possibly multiconnected) solution area (iii) construction of discrete elements of irregular geometry exactly matching the (curved) boundary, (iv) treatment of boundary condiditons and numerical solution of the resulting mathematical system of weakly coupled, ordinary differential equations derived from the conservation principles. Preliminary results of a computer simulation are compared with the available data for a section of the Lower Elbe river. The calculation of the two-dimensional temperature distribution includes existing power plants and industrial sites. (orig.) [de

  16. Change in Sediment Provenance Near the Current Estuary of Yellow River Since the Holocene Transgression

    Science.gov (United States)

    Song, Sheng; Feng, Xiuli; Li, Guogang; Liu, Xiao; Xiao, Xiao; Feng, Li

    2018-06-01

    Sedimentary sequence and sediment provenance are important factors when it comes to the studies on marine sedimentation. This paper studies grain size distribution, lithological characteristics, major and rare earth elemental compositions, micropaleontological features and 14C ages in order to examine sedimentary sequence and sediment provenance of the core BH6 drilled at the mouth of the Yellow River in Bohai Sea. According to the grain size and the micropaleontological compositions, 4 sedimentary units have been identified. Unit 1 (0-8.08 mbsf) is of the delta sedimentary facies, Unit 2 (8.08-12.08 mbsf) is of the neritic shelf facies, Unit 3 (12.08-23.85 mbsf) is of near-estuary beach-tidal facies, and Unit 4 (23.85 mbsf-) is of the continental lake facies. The deposits from Unit 1 to Unit 3 have been found to be marine strata formed after the Holocene transgression at about 10 ka BP, while Unit 4 is continental lacustrine deposit formed before 10 ka BP. The provenances of core BH6 sediments show properties of the continental crust and vary in different sedimentary periods. For Unit 4 sediments, the source regions are dispersed while the main provenance is not clear, although the parent rock characteristics of a few samples are similar to the Luanhe River sediments. For Unit 3, sediments at 21.1-23.85 mbsf have been mainly transported from the Liaohe River, while sediments above 21.1 mbsf are mainly from the Yellow River and partially from the Liaohe River. For Unit 2, the sediments have been mainly transported from the Yellow River, with a small amount from other rivers. For Unit 1, the provenance is mainly the Yellow River catchment. These results help in better understanding the evolution of the Yellow River Delta.

  17. Hydrochemical and isotopic characteristics of estuarial seawater and river water of Bailanghe in Laizhou Bay, China

    Science.gov (United States)

    Yang, Qiaofeng; Xu, Suning; Wang, Ruijiu; Li, Wenpeng; Wang, Zhiyi; Mei, Junjun; Ding, Zhilei; Yang, Peijie; Yu, Liangju; Lv, Tieying; Bai, Gang; Kang, Wei

    2016-04-01

    In the study of seawater intrusion, seawater is usually taken as an end-member that mixes with other source(s). However, compared to standard seawater, the coastal seawater particularly that near the estuary, can be strongly influenced by the rivers into the sea and by coastal human activities. Their composition can be thus continuously changed and redistributed with space and time. Therefore, before investigating seawater intrusion in a certain area, it is essentially important to determine the features of the estuarine seawater (e.g. the mixture percentage between standard seawater and river water). In this study, we aimed to gain a clear situation of the seawater intrusion in Laizhou Bay, Southern Bohai, China. The issue aforementioned was investigated by comparing the stable isotopic and hydrochemical composition of the marine and river water collected in this area. Samples investigated include 5 surface water samples collected at the downstream of the Bailanghe and 7 seawater samples near the estuary of Laizhou Bay. Inert tracers (δD, δ18O, Cl, Br) and reaction tracers (Na, Mg, SO4, HCO3, Ca, NO3) are particularly analyzed. The major results are as follows: 1) All the river water samples fall below the Global Meteoric Water Line in the δD - δ18O diagram, reflecting evaporation of the upstream reservoir water. The seawater samples fall on the mixing line of standard seawater and the river water in the stable isotopic diagram. 2) The Cl-δ18O diagram indicates widespread dissolution of evaporate into the river, while high concentration of Ca and HCO3-, as well as the SO42- - Cl relation of the river water samples reflect the dissolution of CO2 , carbonate and sulfate in the atmosphere and on the ground. 3) The Br/Cl ratios of seawater samples are closed to the marine ratios. This together with the plots of major ions vs. Cl suggest that the seawater samples are originated from the mixture of standard seawater and river water. Therefore, when referring to the

  18. Phytoplankton pigments and functional community structure in relation to environmental factors in the Pearl River Estuary

    Directory of Open Access Journals (Sweden)

    Chao Chai

    2016-07-01

    Full Text Available Two cruises were undertaken in the Pearl River Estuary in November 2011 and March 2012 to analyze the distribution of phytoplankton pigments and to define the relationships of pigment indices and functional community structure with environmental factors. Among 22 pigments, 17 were detected by high-performance liquid chromatography. Chlorophyll a was found in all samples, with a maximum of 7.712 μg L−1 in spring. Fucoxanthin was the most abundant accessory pigment, with mean concentrations of 2.914 μg L−1 and 0.207 μg L−1 in spring and autumn, respectively. Chlorophyll a, chlorophyll c2, fucoxanthin, diadinoxanthin, and diatoxanthin were high in the northern or northwest estuary in spring and in the middle-eastern and northeast estuary in autumn. Chlorophyll b, chlorophyll c3, prasinoxanthin, and peridinin were similarly distributed during the two cruises. Chlorophyll a and fucoxanthin positively correlated with nutrients in spring, whereas 19′-hex-fucoxanthin and 19′-but-fucoxanthin negatively correlated. The biomass proportion of microphytoplankton (BPm was higher in spring, whereas that of picophytoplankton (BPp was higher in autumn. BPm in spring was high in areas with salinity 30. BPm increased but BPn reduced with the increase in nutrient contents. By comparison, BPp reduced with the increase in nutrient contents in spring, but no relationship was found between BPp and nutrient contents in autumn. The ratios of photosynthetic carotenoids to photoprotective carotenoids in the southern estuary approached unity linear relationship in spring and were under the unity line in autumn.

  19. Dynamics of circulation and salt balance in the upper reaches of Periyar river estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Varma, P.U.; Pylee, A.; Sankaranarayanan, V.N.

    The Eulerian residual currents of the upper reaches of Periyar estuary (Kerala, India) were directed down the estuary throughout the water column during the monsoon season. During the summer months the residual flow was directed up the estuary...

  20. Upstream Freshwater and Terrestrial Sources Are Differentially Reflected in the Bacterial Community Structure along a Small Arctic River and Its Estuary

    DEFF Research Database (Denmark)

    Hauptmann, Aviaja Zenia Edna Lyberth; Markussen, Thor N; Stibal, Marek

    2016-01-01

    of different water sources on the microbial communities in Arctic rivers and estuaries remains unknown. In this study we used 16S rRNA gene amplicon sequencing to assess a small river and its estuary on the Disko Island, West Greenland (69°N). Samples were taken in August when there is maximum precipitation...... and temperatures are high in the Disko Bay area. We describe the bacterial community through a river into the estuary, including communities originating in a glacier and a proglacial lake. Our results show that water from the glacier and lake transports distinct communities into the river in terms of diversity...

  1. Distribution and sources of the polycyclic aromatic hydrocarbons in the sediments of the Pearl River estuary, China.

    Science.gov (United States)

    Zhang, Jian-Dong; Wang, You-Shao; Cheng, Hao; Jiang, Zhao-Yu; Sun, Cui-Ci; Wu, Mei-Lin

    2015-10-01

    The Pearl River delta, one of the most prosperous economically region in China, has experienced significant contaminant inputs. However, the dynamics of pollutants in the Pearl River estuary and the adjacent coastal areas are still unclear at present. In the paper, distribution and sources of polycyclic aromatic hydrocarbons (PAHs) were investigated in the surface sediments of the Pearl River estuary. The total PAHs concentrations ranged from 126.08 to 3828.58 ng/g with a mean value of 563.52 ng/g, whereas the highest PAHs were observed in Guangzhou channel. Among the U.S. Environmental Protection Agency's 16 priority PAHs, PAHs with 3-4 rings exhibited relative higher levels. A positive relationship was found between PAHs and total organic carbon. The source analysis further showed that the major sources of PAHs in the Pearl River estuary were originated from the pyrolytic inputs, reflecting a mixed energy structure such as wood, coal and petroleum combustion. In summary, although PAHs in Lingding Bay and the adjacent coastal areas of the Pearl River estuary exhibited a relatively low pollution level, the relatively high pollution level of PAHs in Guangzhou channel will be attended.

  2. Multiproxies (benthic foraminifera, ostracods and biopolymers approach applied to identify the environmental partitioning of the Guadiana River Estuary (Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Lazaro Luiz Mattos Laut

    2016-04-01

    Full Text Available The Guadiana River is the fourth longest river in Europe and is a natural frontier between southern Portugal and Spain. This river was historically used to transport minerals exploited in the region since the Roman Empire and therefore suffered human interventions that have been intensified after the industrial revolution. The Guadiana River has in its limits the Guadiana Valley Natural Park, which is of great value for the Conservation of Geobiodiversity. This study mainly aims to identify zones with the environmental characteristics in the estuarine area of the Guadiana River based on the distribution and ecology of microorganisms (ostracods and foraminifera associated with physicochemical parameters and sedimentological and geochemical (carbohydrate, lipid, protein, total organic carbon and total sulfur data. Fifty-five foraminifera taxa were identified along the estuary with dominance of Ammonia tepida and Miliammina fusca and 13 ostracods taxa with dominance Leptocythere lacertosa and Loxoconcha elliptica. Detrended correspondence analysis (DCA performed using biotic and abiotic variables indicated that pH, grain size, total organic carbon (TOC and lipids were the most influent factors in the distribution of these organisms. Four zones were identified in the Guadiana River estuary: i Low estuary - region with the largest marine influence with sandy sediment, higher salinity and total sulfur and mainly represented by the dominance of estuarine species of foraminifera (Ammonia tepida and Cribroelphidium vadescens and by the ostracods (Darwinula stevensoni, Semicytherura sulcata and Urocythereis oblonga; ii Intermediate estuary - region characterized by neutral pH and sandy sediment enriched in carbohydrates; this region is characterized by the presence of the ostracods species Cytherois fischeri and Neocytherideis subulata and by calcareous and agglutinated species in foraminiferal assemblages; iii Upper estuary - silt, high TOC, proteins and

  3. Ship Emission Inventories in Estuary of the Yangtze River Using Terrestrial AIS Data

    Directory of Open Access Journals (Sweden)

    Xin Yao

    2016-12-01

    Full Text Available Estuary forms a transition zone between inland river and open sea. In China, the estuary of the Yangtze River plays a vital role in connecting the inland and oversea shipping, and witnesses heavy vessel traffic in the recent decades. Nowadays, more attentions have been directed to the issue of ship pollution in busy waterways. In order to investigate the ship emission inventory, this paper presents an Automatic Identification System(AIS based method. AIS data is the realistic data of vessel traffic including dynamic information (position, speed, course, etc. and static information (ship type, dimensions, name, etc.. According to ship dimensions, the power of engines is estimated for different ship types. By using AIS based bottom-up approach, ship emission inventories and shares of air pollutants and GHGs (Greenhouse gases are developed. Spatial distribution of ship emissions is illustrated in the form of heat map. As a case study, the emission inventories are analyzed using AIS data of 2010 in the estuary, and following results are made:(1 shares of the emission are cruise ships 6.59%, bulk carriers 5.16%, container ships 52.96%, tankers 15.16%, fishing ships 9.16%, other ships 10.97%; (2 CO2 is the dominant part of the emission. (3 Areas of highest emission intensity are generally clustered around the South Channel, the North Channel and ports in the vicinity. The proposed method is promising because it is derived from the AIS data which contains not only real data of individual ship but also vessel traffic situation in the study area. It can server as a reference for other researchers and policy makers working in this field.

  4. [Ciliate diversity and spatiotemporal variation in surface sediments of Yangtze River estuary hypoxic zone].

    Science.gov (United States)

    Feng, Zhao; Kui-Dong, Xu; Zhao-Cui, Meng

    2012-12-01

    By using denaturing gradient gel electrophoresis (DGGE) and sequencing as well as Ludox-QPS method, an investigation was made on the ciliate diversity and its spatiotemporal variation in the surface sediments at three sites of Yangtze River estuary hypoxic zone in April and August 2011. The ANOSIM analysis indicated that the ciliate diversity had significant difference among the sites (R = 0.896, P = 0.0001), but less difference among seasons (R = 0.043, P = 0.207). The sequencing of 18S rDNA DGGE bands revealed that the most predominant groups were planktonic Choreotrichia and Oligotrichia. The detection by Ludox-QPS method showed that the species number and abundance of active ciliates were maintained at a higher level, and increased by 2-5 times in summer, as compared with those in spring. Both the Ludox-QPS method and the DGGE technique detected that the ciliate diversity at the three sites had the similar variation trend, and the Ludox-QPS method detected that there was a significant variation in the ciliate species number and abundance between different seasons. The species number detected by Ludox-QPS method was higher than that detected by DGGE bands. Our study indicated that the ciliates in Yangtze River estuary hypoxic zone had higher diversity and abundance, with the potential to supply food for the polyps of jellyfish.

  5. Evaluating Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2009

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Diefenderfer, Heida L.; Borde, Amy B.; Bryson, Amanda J.; Cameron, April; Coleman, Andre M.; Corbett, C.; Dawley, Earl M.; Ebberts, Blaine D.; Kauffman, Ronald; Roegner, G. Curtis; Russell, Micah T.; Silva, April; Skalski, John R.; Thom, Ronald M.; Vavrinec, John; Woodruff, Dana L.; Zimmerman, Shon A.

    2010-10-26

    This is the sixth annual report of a seven-year project (2004 through 2010) to evaluate the cumulative effects of habitat restoration actions in the lower Columbia River and estuary (LCRE). The project, called the Cumulative Effects Study, is being conducted for the U.S. Army Corps of Engineers Portland District (USACE) by the Marine Sciences Laboratory of the Pacific Northwest National Laboratory (PNNL), the Pt. Adams Biological Field Station of the National Marine Fisheries Service (NMFS), the Columbia River Estuary Study Taskforce (CREST), and the University of Washington. The goal of the Cumulative Effects Study is to develop a methodology to evaluate the cumulative effects of multiple habitat restoration projects intended to benefit ecosystems supporting juvenile salmonids in the 235-km-long LCRE. Literature review in 2004 revealed no existing methods for such an evaluation and suggested that cumulative effects could be additive or synergistic. From 2005 through 2009, annual field research involved intensive, comparative studies paired by habitat type (tidal swamp versus marsh), trajectory (restoration versus reference site), and restoration action (tidegate replacement vs. culvert replacement vs. dike breach).

  6. Economic compensation standard for irrigation processes to safeguard environmental flows in the Yellow River Estuary, China

    Science.gov (United States)

    Pang, Aiping; Sun, Tao; Yang, Zhifeng

    2013-03-01

    SummaryAgriculture and ecosystems are increasingly competing for water. We propose an approach to assess the economic compensation standard required to release water from agricultural use to ecosystems while taking into account seasonal variability in river flow. First, we defined agricultural water shortage as the difference in water volume between agricultural demands and actual supply after maintaining environmental flows for ecosystems. Second, we developed a production loss model to establish the relationship between production losses and agricultural water shortages in view of seasonal variation in river discharge. Finally, we estimated the appropriate economic compensation for different irrigation stakeholders based on crop prices and production losses. A case study in the Yellow River Estuary, China, demonstrated that relatively stable economic compensation for irrigation processes can be defined based on the developed model, taking into account seasonal variations in river discharge and different levels of environmental flow. Annual economic compensation is not directly related to annual water shortage because of the temporal variability in river flow rate and environmental flow. Crops that have stable planting areas to guarantee food security should be selected as indicator crops in economic compensation assessments in the important grain production zone. Economic compensation may be implemented by creating funds to update water-saving measures in agricultural facilities.

  7. Historic Habitat Opportunities and Food-Web Linkages of Juvenile Salmon in the Columbia River Estuary, Annual Report of Research.

    Energy Technology Data Exchange (ETDEWEB)

    Bottom, Daniel L.; Simenstad, Charles A.; Campbell, Lance [Northwest Fisheries Science Center

    2009-05-15

    In 2002 with support from the U.S. Army Corps of Engineers (USACE), an interagency research team began investigating salmon life histories and habitat use in the lower Columbia River estuary to fill significant data gaps about the estuary's potential role in salmon decline and recovery . The Bonneville Power Administration (BPA) provided additional funding in 2004 to reconstruct historical changes in estuarine habitat opportunities and food web linkages of Columbia River salmon (Onchorhynchus spp.). Together these studies constitute the estuary's first comprehensive investigation of shallow-water habitats, including selected emergent, forested, and scrub-shrub wetlands. Among other findings, this research documented the importance of wetlands as nursery areas for juvenile salmon; quantified historical changes in the amounts and distributions of diverse habitat types in the lower estuary; documented estuarine residence times, ranging from weeks to months for many juvenile Chinook salmon (O. tshawytscha); and provided new evidence that contemporary salmonid food webs are supported disproportionately by wetland-derived prey resources. The results of these lower-estuary investigations also raised many new questions about habitat functions, historical habitat distributions, and salmon life histories in other areas of the Columbia River estuary that have not been adequately investigated. For example, quantitative estimates of historical habitat changes are available only for the lower 75 km of the estuary, although tidal influence extends 217 km upriver to Bonneville Dam. Because the otolith techniques used to reconstruct salmon life histories rely on detection of a chemical signature (strontium) for salt water, the estuarine residency information we have collected to date applies only to the lower 30 or 35 km of the estuary, where fish first encounter ocean water. We lack information about salmon habitat use, life histories, and growth within the long tidal

  8. Critique and sensitivity analysis of the compensation function used in the LMS Hudson River striped bass models. Environmental Sciences Division publication No. 944

    International Nuclear Information System (INIS)

    Van Winkle, W.; Christensen, S.W.; Kauffman, G.

    1976-12-01

    The description and justification for the compensation function developed and used by Lawler, Matusky and Skelly Engineers (LMS) (under contract to Consolidated Edison Company of New York) in their Hudson River striped bass models are presented. A sensitivity analysis of this compensation function is reported, based on computer runs with a modified version of the LMS completely mixed (spatially homogeneous) model. Two types of sensitivity analysis were performed: a parametric study involving at least five levels for each of the three parameters in the compensation function, and a study of the form of the compensation function itself, involving comparison of the LMS function with functions having no compensation at standing crops either less than or greater than the equilibrium standing crops. For the range of parameter values used in this study, estimates of percent reduction are least sensitive to changes in YS, the equilibrium standing crop, and most sensitive to changes in KXO, the minimum mortality rate coefficient. Eliminating compensation at standing crops either less than or greater than the equilibrium standing crops results in higher estimates of percent reduction. For all values of KXO and for values of YS and KX at and above the baseline values, eliminating compensation at standing crops less than the equilibrium standing crops results in a greater increase in percent reduction than eliminating compensation at standing crops greater than the equilibrium standing crops

  9. Critique and sensitivity analysis of the compensation function used in the LMS Hudson River striped bass models. Environmental Sciences Division publication No. 944

    Energy Technology Data Exchange (ETDEWEB)

    Van Winkle, W.; Christensen, S.W.; Kauffman, G.

    1976-12-01

    The description and justification for the compensation function developed and used by Lawler, Matusky and Skelly Engineers (LMS) (under contract to Consolidated Edison Company of New York) in their Hudson River striped bass models are presented. A sensitivity analysis of this compensation function is reported, based on computer runs with a modified version of the LMS completely mixed (spatially homogeneous) model. Two types of sensitivity analysis were performed: a parametric study involving at least five levels for each of the three parameters in the compensation function, and a study of the form of the compensation function itself, involving comparison of the LMS function with functions having no compensation at standing crops either less than or greater than the equilibrium standing crops. For the range of parameter values used in this study, estimates of percent reduction are least sensitive to changes in YS, the equilibrium standing crop, and most sensitive to changes in KXO, the minimum mortality rate coefficient. Eliminating compensation at standing crops either less than or greater than the equilibrium standing crops results in higher estimates of percent reduction. For all values of KXO and for values of YS and KX at and above the baseline values, eliminating compensation at standing crops less than the equilibrium standing crops results in a greater increase in percent reduction than eliminating compensation at standing crops greater than the equilibrium standing crops.

  10. The pollution history of the Savannah River Estuary. Final report 1 Sep 1976--31 Dec 1977

    International Nuclear Information System (INIS)

    Goldberg, E.D.; Griffin, J.J.; Hodge, V.; Koide, M.

    1978-06-01

    Records of natural and pollutant fluxes to the Savannah River Estuary are found in some river and marsh deposits into which time frames can be introduced by 210 Pb or plutonium geochronologies. Plutonium releases from the Savannah River Plant are evident in only one deposit and in marsh grass which received the transuranic element from atmospheric transport. The pollution records can be disturbed by bioturbative activities of organisms, by the input of marine solid phases to the estuarine deposits, and by river scour and fill

  11. Evaluation of the Level of Organochlorinated Pesticides Contamination in Environment of the Red River and its Balat Estuary

    International Nuclear Information System (INIS)

    Nguyen Manh Am; Dang Duc Nhan; Vo Van Thuan; Nguyen Duc Cu; Luu Van Dieu; Nguyen Chu Hoi

    1995-01-01

    The pollution level of OC pesticides such as Lindane, DDT and its metabolites contaminants in water, sediments and Biota collected along the Red River and from the Balat estuary have, for the first time in the North of Vietnam, been determined by GC technique using capillary columns and electron capture detection (ECD). The concentration of DDT and DDE was found to be up to 38.4 ppb and 27.3 ppb, respectively, in sediments from the Red River and its Balat estuary. Lindane residue in Red River's and Balat estuary's sediments was found at level of 1.3-4.2 and 14.6-52.6 ppb, respectively. In water Lindane contaminant was detected in the sample collected from the estuarine area only, while DDE was found in both River and estuarine water. Residue of Lindane in mussel flesh was found to be always higher (up to 145 ppb) than that of any DDT's metabolites, e.g. the highest value of DDE contaminant is 66 ppb. The finding shows that Lindane contamination in marine environmental samples from the Balat estuary is higher as compared with those from the Mediterranean Sea but DDT's ones are at the same level. (author). 8 refs., 6 tabs., 1 map

  12. Emergy and Economic Evaluations of Four Fruit Production Systems on Reclaimed Wetlands Surrounding the Pearl River Estuary, China

    Science.gov (United States)

    Emergy and economic methods were used to evaluate and compare a traditional tropical fruit cultivation system, for bananas, and three newly introduced fruit cultivation systems, for papaya, guava and wampee, on reclaimed wetlands of the Pearl River Estuary, China. The evaluations...

  13. Polycyclic aromatic hydrocarbons in suspended particulate matter and sediments from the Pearl River Estuary and adjacent coastal areas, China

    International Nuclear Information System (INIS)

    Luo Xiaojun; Chen Shejun; Mai Bixian; Yang Qingshu; Sheng Guoying; Fu Jiamo

    2006-01-01

    The spatial distribution, composition, and sources of polycyclic aromatic hydrocarbons (PAHs) in sediments and suspended particulate matter (SPM) from the Pearl River Estuary and adjacent coastal areas were examined. Total PAH concentrations varied from 189 to 637 ng/g in sediments and 422 to 1850 ng/g in SPM. PAHs were dominated by 5,6-ring compounds in sediments and by 2,3-ring compounds in SPM samples. Assessment of PAH sources suggested that biomass and coal combustion is the major PAH source to the outer part of the estuary sediments and that petroleum combustion is the major PAH source to the inner part of estuary sediments. As for SPM samples, PAH isomer pair ratios indicated multiple (petroleum, petroleum combustion, and biomass and coal combustion) PAH sources, and significant temporal variations could exist for the sources of water column PAHs in the study area. The distribution of perylene in SPM samples indicated that the river was the dominant source of perylene in SPM and that perylene could be taken as an index to assess the contribution of river inflow to the total PAHs in SPM samples. The high concentration of perylene in the sediment was indicative of an in situ biogenic origin. - PAH were determined in suspended particulate matter and sediments from Pearl River Estuary

  14. River-tide dynamics : Exploration of nonstationary and nonlinear tidal behavior in the Yangtze River estuary

    NARCIS (Netherlands)

    Guo, L.; Van der Wegen, M.; Jay, D.A.; Matte, P.; Wang, Z.B.; Roelvink, J.A.; He, Q.

    2015-01-01

    River-tide dynamics remain poorly understood, in part because conventional harmonic analysis (HA) does not cope effectively with nonstationary signals. To explore nonstationary behavior of river tides and the modulation effects of river discharge, this work analyzes tidal signals in the Yangtze

  15. Physical, chemical, and biological aspects of the Duwamish River Estuary, King County, Washington, 1963-67

    Science.gov (United States)

    Santos, John F.; Stoner, J.D.

    1972-01-01

    This report describes the significant results to 1967 of a comprehensive study that began in 1963 to evaluate what changes take place in an estuary as the loads .of raw and partially treated industrial and municipal wastes are replaced by effluent from a secondary treatment plant. The study area is the Duwamish River estuary, about 18.3 river kilometers long. At mean sea level the estuary has a water-surface area of about 1 square mile and a mean width of 440 feet. At the lowest and highest recorded tides, the volume of the estuary is about 205 and 592 million cubic feet, respectively. The estuary is well stratified (salt-wedge type) at fresh-water inflows greater than 1,000 cfs (cubic feet per second), but when inflow rates are less than 1,000 cfs the lower 5.6 kilometers of the estuary grades into the partly mixed type. The crosschannel salinity distribution is uniform for a given location and depth. Salinity migration is controlled by tides and fresh-water inflow. At fresh-water inflow rates greater than 1,000 cfs, water in the upper 8.4 kilometers of the estuary is always fresh regardless of tide. At inflow rates less than 600 cfs and tide heights greater than 10 feet; some salinity has been detected 16.1 kilometers above the mouth of the estuary. Studies using a fluorescent dye show that virtually no downward mixing into the salt wedge occurs; soluble pollutants introduced at the upper end of the estuary stay in the surface layer (5-15 ft thick). On the basis of dye studies when fresh-water inflow is less than 400 cfs, it is estimated that less than 10 percent of a pollutant will remain in the estuary a minimum of 7 days. Longitudinal dispersion coefficients for the surface layer have been determined to be on the order of 100-400 square feet per second. Four water-quality stations automatically monitor DO (dissolved oxygen), water temperature, pH, and specific conductance; at one station solar radiation also is measured. DO concentration in the surface layer

  16. Volatile organic compounds in urban rivers and their estuaries in Osaka, Japan.

    Science.gov (United States)

    Yamamoto, K; Fukushima, M; Kakutani, N; Kuroda, K

    1997-01-01

    The levels and distribution of 55 volatile organic compounds (VOCs) were determined by purge and trap GC-MS on water samples from 30 sites within the urban rivers and estuaries of Osaka, a populated industrialized city of Japan. Forty of 55 target VOCs listed in the US EPA Method 524.2 were detected. Dichloromethane (DCM) was found at higher levels at all of the sampling sites. The distribution of dominant VOCs followed four different patterns. First, the most common VOCs (DCM, toluene, trichloroethene and tetrachloroethene) showed concentration maxima in the river segments, and the sites of maximum concentration fluctuated due to irregular large spills and/or loadings. Second, one VOC (cis-1,2-dichloroethene) was evenly distributed in particular rivers due to fixed loadings. Both of these patterns were found in the upper and middle reaches. Third, some of VOCs (1,2,3-trichloropropane and benzene) were specific to a single industrial site and truceable to those sources. Finally, some VOCs showed no concentration maxima along the rivers and entered from multiple sources (chloroform and bromodichloromethane). Diurnal variations of VOCs at the border of the city area, receiving domestic and industrial discharges, provided information to interpret their observed downstream distribution and possible sources.

  17. Assessment of Water Salinity Model Using Hydrodynamic Numerical Modelling in Estuary of Selangor River, Malaysia

    International Nuclear Information System (INIS)

    Mohd Ekhwan Toriman; Mohd Ekhwan Toriman; Norbaya Hashim; Mohd Khairul Amri Kamarudin; Abdul Jalil Hassan; Ayaari Muhamad; Nor Azlina Abd Aziz

    2015-01-01

    Issues such as water pollution and extraction of water from Sungai Selangor system has been said to be the cause of fading fireflies. Salinity intrusion into estuary of the Sungai Selangor has been carried out on a hydrodynamic numerical modeling to access the parameter that governed the amount of salt in the river. The berembang trees on the river bank that become the fireflies habitat need some amount of salt for proper growth. Living at the lower reaches of Sungai Selangor, the fireflies are affected not only by the activities in their vicinity, but by activities in the entire river basin. Rapid economic development in the basin and the strong demand for the water resources puts pressure on the ecosystem. This research has been carried out to investigate the effect of water extraction along Sungai Selangor towards altering the amount of salt content in the river. The hydrodynamic modeling with regards to the salt content is expected to support long term assessment that may affect the berembang trees as a result of changes in the flow from upstream because of the water abstraction activity for domestic water supply. (author)

  18. Estuaries of the northeastern United States: Habitat and land use signatures

    Science.gov (United States)

    Roman, C.T.; Jaworski, N.; Short, F.T.; Findlay, S.; Warren, R.S.

    2000-01-01

    Geographic signatures are physical, chemical, biotic, and human-induced characteristics or processes that help define similar or unique features of estuaries along latitudinal or geographic gradients. Geomorphologically, estuaries of the northeastern U.S., from the Hudson River estuary and northward along the Gulf of Maine shoreline, are highly diverse because of a complex bedrock geology and glacial history. Back-barrier estuaries and lagoons occur within the northeast region, but the dominant type is the drowned-river valley, often with rocky shores. Tidal range and mean depth of northeast estuaries are generally greater when compared to estuaries of the more southern U.S. Atlantic coast and Gulf of Mexico. Because of small estuarine drainage basins, low riverine flows, a bedrock substrate, and dense forest cover, sediment loads in northeast estuaries are generally quite low and water clarity is high. Tidal marshes, seagrass meadows, intertidal mudflats, and rocky shores represent major habitat types that fringe northeast estuaries, supporting commercially-important fauna, forage nekton and benthos, and coastal bird communities, while also serving as links between deeper estuarine waters and habitats through detritus-based pathways. Regarding land use and water quality trends, portions of the northeast have a history of over a century of intense urbanization as reflected in increased total nitrogen and total phosphorus loadings to estuaries, with wastewater treatment facilities and atmospheric deposition being major sources. Agricultural inputs are relatively minor throughout the northeast, with relative importance increasing for coastal plain estuaries. Identifying geographic signatures provides an objective means for comparing the structure function, and processes of estuaries along latitudinal gradients.

  19. Report on the workshop examining the potential effects of hydroelectric development on Beluga of the Nelson River Estuary, Winnipeg, Manitoba, November 6 and 7, 1990

    International Nuclear Information System (INIS)

    Lawrence, M.J.; Paterson, M.; Baker, R.F.; Schmidt, R.

    1992-01-01

    A summary is presented of discussions and conclusions at a workshop held to examine the potential effects of hydroelectric development on beluga whales of the Nelson River estuary in Manitoba. Background information is provided on the estuary, beluga whales and their use of arctic and subarctic estuaries, and hydroelectric development on the Nelson River. Potential impacts of such development on the whales are reviewed in the categories of direct effects of changes in physical-chemical conditions (temperature and discharge), indirect effects of disturbances mediated through the food chain, and effects on socioeconomic conditions that may affect beluga whales. Since the biology of beluga whales and other phenomena of interest in this study are poorly known, recommendations are made for research and monitoring activities in the Nelson River estuary. In general, the workshop participants felt that changes in the estuary due to hydroelectric development would not be large enough to affect beluga whales strongly. 34 refs., 1 fig

  20. Oceanographic data collected from Saturn Estuary Station 03 by Center for Coastal Margin Observation and Prediction (CMOP) and assembled by Northwest Association of Networked Ocean Observation Systems (NANOOS) in the Columbia River Estuary and North East Pacific Ocean from 2008-04-19 to 2017-08-01 (NCEI Accession 0162617)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0162617 contains biological, chemical and physical data collected at Saturn Estuary Station 03, a fixed station in the Columbia River estuary -...

  1. Oceanographic data collected from Saturn Estuary Station 01 by Center for Coastal Margin Observation and Prediction (CMOP) and assembled by Northwest Association of Networked Ocean Observation Systems (NANOOS) in the Columbia River Estuary and North East Pacific Ocean from 2008-04-13 to 2017-07-01 (NCEI Accession 0162182)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0162182 contains biological, chemical and physical data collected at Saturn Estuary Station 01, a fixed station in the Columbia River estuary -...

  2. CO2 emissions from a temperate drowned river valley estuary adjacent to an emerging megacity (Sydney Harbour)

    Science.gov (United States)

    Tanner, E. L.; Mulhearn, P. J.; Eyre, B. D.

    2017-06-01

    The Sydney Harbour Estuary is a large drowned river valley adjacent to Sydney, a large urban metropolis on track to become a megacity; estimated to reach a population of 10 million by 2100. Monthly underway surveys of surface water pCO2 were undertaken along the main channel and tributaries, from January to December 2013. pCO2 showed substantial spatio-temporal variability in the narrow high residence time upper and mid sections of the estuary, with values reaching a maximum of 5650 μatm in the upper reaches and as low as 173 μatm in the mid estuary section, dominated by respiration and photosynthesis respectively. The large lower estuary displayed less variability in pCO2 with values ranging from 343 to 544 μatm controlled mainly by tidal pumping and temperature. Air-water CO2 emissions reached a maximum of 181 mmol C m-2 d-1 during spring in the eutrophic upper estuary. After a summer high rainfall event nutrient-stimulated biological pumping promoted a large uptake of CO2 transitioning the Sydney Harbour Estuary into a CO2 sink with a maximum uptake of rate of -10.6 mmol C m-2 d-1 in the mid-section of the estuary. Annually the Sydney Harbour Estuary was heterotrophic and a weak source of CO2 with an air-water emission rate of 1.2-5 mmol C m-2 d-1 (0.4-1.8 mol C m-2 y-1) resulting in a total carbon emission of around 930 tonnes per annum. CO2 emissions (weighted m3 s-1 of discharge per km2 of estuary surface area) from Sydney Harbour were an order of magnitude lower than other temperate large tectonic deltas, lagoons and engineered systems of China, India, Taiwan and Europe but were similar to other natural drowned river valley systems in the USA. Discharge per unit area appears to be a good predictor of CO2 emissions from estuaries of a similar climate and geomorphic class.

  3. Impact of the river Liffey discharge on nutrient and chlorophyll concentrations in the Liffey estuary and Dublin Bay (Irish Sea)

    Science.gov (United States)

    O'Higgins, T. G.; Wilson, J. G.

    2005-08-01

    Temperature, salinity, nutrients (total oxidised nitrogen (TON), ammonium (NH 4) and orthophosphate (PO 4)) and chlorophyll a were monitored in the Liffey estuary and Dublin Bay from June 2000 to June 2003. Four groups of sites were defined comprising the upper estuary (Gp. I), the outer estuary (Gp. III) with a small set (Gp. II) of sites between Groups I and III heavily influenced by the sewage treatment works outflow, and the Bay proper (Gp. IV). Riverine inputs of TON and PO 4 were calculated at an average of 826 t N y -1 and 31 t P y -1, respectively, and were largely controlled by flow rate. The sewage treatment works were identified as a major source of PO 4 and NH 4 to the system. Mixing in the upper estuary of nutrient limited saline waters with hypernutrified river water regularly (i.e. annually) produced relatively high concentrations of chlorophyll a (>10 mg chl a m -3), and also sporadic blooms with extremely high chlorophyll a values (max. 121.6 mg chl a m -3). These latter phytoplankton blooms occurred in high salinity waters and were due to mixing of nutrient limited saline waters and nutrient rich river waters. The mean annual flux of phytoplankton carbon from the river Liffey was calculated at 23.5 t C y -1, of which half was accumulated or remineralised in the estuary and did not enter the Bay. In the Bay proper (Gp. IV) summer nutrient concentrations dropped below detection limits, and chlorophyll a concentrations followed the classic pattern with a spring bloom maximum of 5.5 mg chl a m -3. This pattern in nutrients and chlorophyll a came from the advection of waters into the Bay from an offshore source. Overall while there was considerable evidence for eutrophication in the estuary, the bay itself showed little biological response to nutrient loading.

  4. Assessment of the Mutagenicity of Sediments from Yangtze River Estuary Using Salmonella Typhimurium/Microsome Assay

    Science.gov (United States)

    Liu, Li; Chen, Ling; Floehr, Tilman; Xiao, Hongxia; Bluhm, Kerstin; Hollert, Henner; Wu, Lingling

    2015-01-01

    Sediments in estuaries are of important environmental concern because they may act as pollution sinks and sources to the overlying water body. These sediments can be accumulated by benthic organisms. This study assessed the mutagenic potential of sediment extracts from the Yangtze River estuary by using the Ames fluctuation assay with the Salmonella typhimurium his (−) strain TA98 (frameshift mutagen indicator) and TA100 (baseshift mutagen indicator). Most of the sediment samples were mutagenic to the strain TA98, regardless of the presence or absence of exogenous metabolic activation (S9 induction by β-naphthoflavone/phenobarbital). However, none of the samples were mutagenic to the strain TA100. Thus, the mutagenicity pattern was mainly frameshift mutation, and the responsible toxicants were both direct (without S9 mix) and indirect (with S9 mix) mutagens. The mutagenicity of the sediment extracts increased when S9 was added. Chemical analysis showed a poor correlation between the content of priority polycyclic aromatic hydrocarbons and the detected mutagenicity in each sample. The concept of effect-directed analysis was used to analyze possible compounds responsible for the detected mutagenic effects. With regard to the mutagenicity of sediment fractions, non-polar compounds as well as weakly and moderately polar compounds played a main role. Further investigations should be conducted to identify the responsible components. PMID:26606056

  5. Effect of water flux and sediment discharge of the Yangtze River on PAHs sedimentation in the estuary.

    Science.gov (United States)

    Li, Rufeng; Feng, Chenghong; Wang, Dongxin; He, Maozhi; Hu, Lijuan; Shen, Zhenyao

    2016-12-01

    Historical distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) and their carriers (i.e., organic matter and mineral particles) in the sediment cores of the Yangtze Estuary were investigated, with emphasis laid on the role of the Yangtze River. Grain size component of sediments (clay, silt, and sand) and organic carbon (black carbon and total organic carbon) in the sediment cores were markedly affected by water flux and sediment discharge of the Yangtze River. Qualitative and quantitative analysis results showed that sands and black carbon acted as the main carriers of PAHs. The sedimentation of two-ring to three-ring PAHs in the estuary had significant correlations with water flux and sediment discharge of the Yangtze River. The relative lower level of the four-ring and five-ring to six-ring PAHs concentrations appeared around the year 2003 and remained for the following several years. This time period accorded well with the water impoundment time of the Three Gorges Reservoir. The decreased level of two-ring to three-ring PAHs occurred in the year 1994, and the peak points around the year 2009 indicated that PAHs sedimentation in the estuary also had close relationship to severe drought and flood in the catchments. The findings presented in this paper could provide references for assessing the impacts of water flux and sediment discharge on the historical deposition of PAHs and their carriers in the Yangtze Estuary.

  6. 226Ra and 228Ra in the mixing zones of the Pee Dee River-Winyah Bay, Yangtze River and Delaware Bay Estuaries

    International Nuclear Information System (INIS)

    Elsinger, R.J.; Moore, W.S.

    1984-01-01

    226 Ra and 228 Ra have non-conservative excess concentrations in the mixing zones of the Pee Dee River-Winyah Bay estuary, the Yangtze River estuary, and the Delaware Bay estuary. Laboratory experiments, using Pee Dee River sediment, indicate desorption of 226 Ra to increase with increasing salinities up to 20 per mille. In Winyah Bay desorption from river-borne sediments could contribute almost all of the increases for both isotopes. Desorption adds only a portion of the excess 228 Ra measured in the Yangtze River and adjacent Shelf waters and Delaware Bay. In the Yangtze River the mixing zone extends over a considerable portion of the Continental Shelf where 228 Ra is added to the water column by diffusion from bottom sediments, while 226 Ra concentrations decrease from dilution. Diffusion of 228 Ra from bottom sediments in Delaware Bay primarily occurs in the upper part of the bay ( 228 Ra of 0.33 dpm cm -2 year was determined for Delaware Bay. (author)

  7. The distribution and partitioning of common antibiotics in water and sediment of the Pearl River Estuary, South China.

    Science.gov (United States)

    Liang, Ximei; Chen, Baowei; Nie, Xiangping; Shi, Zhen; Huang, Xiaoping; Li, Xiangdong

    2013-09-01

    Antibiotics released into the aquatic environment play an important role in the spread of antibiotic resistance. In the Pearl River Estuary (PRE) and the coastal zone, the concentrations of antibiotics decreased from the Pearl River to the estuary, suggesting that antibiotics primarily originated from river tributaries and terrigenous sources. Within the PRE area, the concentrations of antibiotics in water were higher in the west coast than the east side, reflecting the high density of anthropogenic activities and hydraulic conditions along the west riverbank. Seasonal variations were also observed for most of detected antibiotics in water. The pseudo-partitioning coefficient of norfloxacin had a good correlation with the TOC content of sediments, as did erythromycin-H2O with the pH of water. The results suggest that environmental conditions can significantly affect the distribution of antibiotics between water and sediment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Ecological status and sources of anthropogenic contaminants in mangroves of the Wouri River Estuary (Cameroon)

    KAUST Repository

    Fusi, Marco

    2016-07-07

    Mangroves are critically threatened by human activities, despite the important ecosystem functions and services they provide. Mangroves in Cameroon represent no exception to the worldwide trend of mangrove destruction, especially around Douala, on the Wouri river estuary. In two sites around Douala, we assessed the presence of sterols, PAHs, PCBs, DEHP, DDT and its metabolite p,p\\'-DDE and potentially toxic metals in sediment samples. As a proxy of ecological quality, we measured the diversity and abundance of macrobenthos assemblages. We detected p,p\\'-DDE contamination, with concentrations higher than 3μgkg-1 in 16 out of 26 samples which were attributed to recent widespread use of DDT. The detection of sterols revealed faecal contamination. Significant sensitivity of the macrobenthos to contaminants was revealed, with possible implications on the overall mangrove vulnerability to climate change and on the provision of ecosystem services to local populations. © 2016 Elsevier Ltd.

  9. Using Fishers Knowledge in Community Based Fisheries Management in the River Nun Estuary, Niger Delta

    Directory of Open Access Journals (Sweden)

    Ngodigha Sabina

    2018-02-01

    Full Text Available A study of fishers’ knowledge in community based fisheries management practices in the Nun River estuary were conducted to assess the contribution of fishers’ knowledge to fisheries resources conservation. The total number of fishers that operated in the area were 390, and 221 fishers were interviewed based on a minimum of 10 years fishing experience using the socio-ecological approach. The laws introduced are banned on the use of mesh size less than five cm and banned on chemical fishing. Fishers caught using chemicals to fish were arrested and handed over to the police for prosecution. The management method has enhanced conservation of fisheries’ resources, which is a major source of livelihood for the people. It is therefore pertinent to introduce community based laws to check over exploitation of fisheries’ resources in fishing communities in the Niger Delta.

  10. A dinoflagellate Cochlodinium geminatum bloom in the Zhujiang (Pearl) River estuary in autumn 2009

    Science.gov (United States)

    Ke, Zhixin; Huang, Liangmin; Tan, Yehui; Song, Xingyu

    2012-05-01

    A severe Cochlodinium geminatum red tide (>300 km2) was observed in the Zhujiang (Pearl) River estuary, South China Sea in autumn 2009. We evaluated the environmental conditions and phytoplankton community structure during the outbreak. The red tide water mass had significantly higher dissolved inorganic phosphate (DIP), ammonia, and temperature, but significantly lower nitrite, nitrate, dissolved inorganic nitrogen (DIN), and DIN/DIP relative to the non-red-tide zones. The phytoplankton assemblage was dominated by dinoflagellates and diatoms during the red tide. C. geminatum was the most abundant species, with a peak density of 4.13×107 cell/L, accounting for >65% of the total phytoplankton density. The DIN/DIP ratio was the most important predictor of species, accounting for 12.45% of the total variation in the phytoplankton community. Heavy phosphorus loading, low precipitation, and severe saline intrusion were likely responsible for the bloom of C. geminatum.

  11. Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2007

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Diefenderfer, Heida L.; Borde, Amy B.; Dawley, Earl M.; Ebberts, Blaine D.; Putman, Douglas A.; Roegner, G. C.; Russell, Micah; Skalski, John R.; Thom, Ronald M.; Vavrinec, John

    2008-10-01

    The goal of this multi-year study (2004-2010) is to develop a methodology to evaluate the cumulative effects of multiple habitat restoration projects intended to benefit ecosystems supporting juvenile salmonids in the lower Columbia River and estuary. Literature review in 2004 revealed no existing methods for such an evaluation and suggested that cumulative effects could be additive or synergistic. Field research in 2005, 2006, and 2007 involved intensive, comparative studies paired by habitat type (tidal swamp vs. marsh), trajectory (restoration vs. reference site), and restoration action (tide gate vs. culvert vs. dike breach). The field work established two kinds of monitoring indicators for eventual cumulative effects analysis: core and higher-order indicators. Management implications of limitations and applications of site-specific effectiveness monitoring and cumulative effects analysis were identified.

  12. Ecological status and sources of anthropogenic contaminants in mangroves of the Wouri River Estuary (Cameroon).

    Science.gov (United States)

    Fusi, Marco; Beone, Gian Maria; Suciu, Nicoleta Alina; Sacchi, Angela; Trevisan, Marco; Capri, Ettore; Daffonchio, Daniele; Din, Ndongo; Dahdouh-Guebas, Farid; Cannicci, Stefano

    2016-08-30

    Mangroves are critically threatened by human activities, despite the important ecosystem functions and services they provide. Mangroves in Cameroon represent no exception to the worldwide trend of mangrove destruction, especially around Douala, on the Wouri river estuary. In two sites around Douala, we assessed the presence of sterols, PAHs, PCBs, DEHP, DDT and its metabolite p,p'-DDE and potentially toxic metals in sediment samples. As a proxy of ecological quality, we measured the diversity and abundance of macrobenthos assemblages. We detected p,p'-DDE contamination, with concentrations higher than 3μgkg(-1) in 16 out of 26 samples which were attributed to recent widespread use of DDT. The detection of sterols revealed faecal contamination. Significant sensitivity of the macrobenthos to contaminants was revealed, with possible implications on the overall mangrove vulnerability to climate change and on the provision of ecosystem services to local populations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Nitrogen cycle of a typical Suaeda salsa marsh ecosystem in the Yellow River estuary.

    Science.gov (United States)

    Mou, Xiaojie; Sun, Zhigao; Wang, Lingling; Wang, Chuanyuan

    2011-01-01

    The nitrogen (N) biological cycle of the Suaeda salsa marsh ecosystem in the Yellow River estuary was studied during 2008 to 2009. Results showed that soil N had significant seasonal fluctuations and vertical distribution. The N/P ratio (15.73 +/- 1.77) of S. salsa was less than 16, indicating that plant growth was limited by both N and P. The N absorption coefficient of S. salsa was very low (0.007), while the N utilization and cycle coefficients were high (0.824 and 0.331, respectively). The N turnover among compartments of S. salsa marsh showed that N uptake from aboveground parts and roots were 2.539 and 0.622 g/m2, respectively. The N translocation from aboveground parts to roots and from roots to soil were 2.042 and 0.076 g/m2, respectively. The N translocation from aboveground living bodies to litter was 0.497 g/m2, the annual N return from litter to soil was far less than 0.368 g/m2, and the net N mineralization in topsoil during the growing season was 0.033 g/m2. N was an important limiting factor in S. salsa marsh, and the ecosystem was classified as unstable and vulnerable. S. salsa was seemingly well adapted to the low-nutrient status and vulnerable habitat, and the nutrient enrichment due to N import from the Yellow River estuary would be a potential threat to the S. salsa marsh. Excessive nutrient loading might favor invasive species and induce severe long-term degradation of the ecosystem if human intervention measures were not taken. The N quantitative relationships determined in our study might provide a scientific basis for the establishment of effective measures.

  14. Impacts of sea cucumber farming on biogeochemical characteristics in the Yellow River estuary, Northern China

    Science.gov (United States)

    Fu, Jing; Yokoyama, Hisashi; Cui, Baoshan; Zhou, Jin; Yan, Jiaguo; Ma, Xu; Shibata, Shozo

    2017-02-01

    To investigate the potential environmental effects of pond farming for Apostichopus japonicas in Yellow River estuary, we examined discrepancies of distance-based typical pollution indicators (TOC, TN, NO3-, NH4+, NO2- and PO43-) and biochemical tracers (δ13C and δ15N) in water column and sediment, as well as dietary characteristics of dominant macrobenthos between farming and non-farming areas. The results revealed that studied variables in water column showed no uniform spatial differences. Meanwhile, those in sediment displayed similar decrease tendencies from farming pond to the adjacent tidal flat, which was considered to represent the environmental effects of farming. Biochemical tracers (δ13C and δ15N) in both water column and sediment confirmed the origin of organic matters from the aquaculture waste. The detectable dispersion distance of aquaculture waste was restricted to an area within 50 m distance as determined by most variables in sediment (TOC, TN, NO3- and NH4+), particularly by C:N ratio and δ13C with which origins of the wastes were traced. Bayesian mixing models indicated that in the farming area BMA had a larger contribution, while POM(marine) showed a smaller contribution to the diets of Helice tridens and Macrophthalmus abbreviates compared to those in the non-farming area. The overall results showed that pond farming for Apostichopus japonicus in the Yellow River estuary altered the local environment to a certain extent. For methodological consideration, sediment biogeochemical characteristics as a historical recorder much more effectively reflected aquaculture waste accumulation, and stable isotope approaches are efficient in tracing the origin and extent of various allogenous sources.

  15. Stratification and salt-wedge in the Seomjin river estuary under the idealized tidal influence

    Science.gov (United States)

    Hwang, Jin Hwan; Jang, Dongmin; Kim, Yong Hoon

    2017-12-01

    Advection, straining, and vertical mixing play primary roles in the process of estuarine stratification. Estuaries can be classified as salt-wedge, partially-mixed or well-mixed depending on the vertical density structure determined by the balancing of advection, mixing and straining. In particular, straining plays a major role in the stratification of the estuarine water body along the estuarine channel. Also, the behavior of a salt wedge with a halocline shape in a stratified channel can be controlled by the competition between straining and mixing induced by buoyancy from the riverine source and tidal forcing. The present study uses Finite Volume Coastal Ocean Model (FVCOM) to show that straining and vertical mixing play major roles in controlling along-channel flow and stratification structures in the Seomjin river estuary (SRE) under idealized conditions. The Potential Energy Anomaly (PEA) dynamic equation quantifies the governing processes thereby enabling the determination of the stratification type. By comparing terms in the equation, we examined how the relative strengths of straining and mixing alter the stratification types in the SRE due to changes in river discharge and the depth resulting from dredging activities. SRE under idealized tidal forcing tends to be partially-mixed based on an analysis of the balance between terms and the vertical structure of salinity, and the morphological and hydrological change in SRE results in the shift of stratification type. While the depth affects the mixing, the freshwater discharge mainly controls the straining, and the balance between mixing and straining determines the final state of the stratification in an estuarine channel. As a result, the development and location of a salt wedge along the channel in a partially mixed and highly stratified condition is also determined by the ratio of straining to mixing. Finally, our findings confirm that the contributions of mixing and straining can be assessed by using the

  16. Combined Stable Carbon Isotope and C/N Ratios as Indicators of Source and Fate of Organic Matter in the Bang Pa kong River Estuary, Thailand

    International Nuclear Information System (INIS)

    Boonphakdee, Thanomsak; Kasai, Akihide; Fujiwara, Tateki; Sawangwong, Pichan; Cheevaporn, Voravit

    2007-08-01

    Full text: Stable carbon isotopes and C/N ratios of particulate organic matter (POM) in suspended solids and surficial sediment were used to define the spatial and temporal variability in an anthropogenic tropical river estuary, the Bang Pa kong River Estuary. Samples were taken along salinity gradients during the four different river discharges in the beginning, high river discharge and at the end of the wet season, and low river discharge during the dry season. The values of [C/N]a ratio and d13C in the river estuary revealed significant differences from those of the offshore station. Conservative behaviors of [C/N]a and d13C in the estuary during the wet season indicated major contribution of terrigenous C3 plants derived OM. By contrast, during the dry season, marine input mainly dominated OM contribution with an evidence of anthropogenic input to the estuary. These compositions of the bulk sedimentary OM were dominated by paddy rice soils and marine derived OM during the wet and dry seasons, respectively. These results show that the combined stable carbon isotopes and C/N ratios can be used to identify the source and fate of OM even in a river estuary. This tool will be useful to achieve sustainable management in coastal zone

  17. Tracing the origin of the oxygen-consuming organic matter in the hypoxic zone in a large eutrophic estuary: the lower reach of the Pearl River Estuary, China

    Science.gov (United States)

    Su, Jianzhong; Dai, Minhan; He, Biyan; Wang, Lifang; Gan, Jianping; Guo, Xianghui; Zhao, Huade; Yu, Fengling

    2017-09-01

    We assess the relative contributions of different sources of organic matter, marine vs. terrestrial, to oxygen consumption in an emerging hypoxic zone in the lower Pearl River Estuary (PRE), a large eutrophic estuary located in Southern China. Our cruise, conducted in July 2014, consisted of two legs before and after the passing of Typhoon Rammasun, which completely de-stratified the water column. The stratification recovered rapidly, within 1 day after the typhoon. We observed algal blooms in the upper layer of the water column and hypoxia underneath in bottom water during both legs. Repeat sampling at the initial hypoxic station showed severe oxygen depletion down to 30 µmol kg-1 before the typhoon and a clear drawdown of dissolved oxygen after the typhoon. Based on a three endmember mixing model and the mass balance of dissolved inorganic carbon and its isotopic composition, the δ13C of organic carbon remineralized in the hypoxic zone was -23.2 ± 1.1 ‰. We estimated that 65 ± 16 % of the oxygen-consuming organic matter was derived from marine sources, and the rest (35 ± 16 %) was derived from the continent. In contrast to a recently studied hypoxic zone in the East China Sea off the Changjiang Estuary where marine organic matter dominated oxygen consumption, here terrestrial organic matter significantly contributed to the formation and maintenance of hypoxia. How varying amounts of these organic matter sources drive oxygen consumption has important implications for better understanding hypoxia and its mitigation in bottom waters.

  18. Upstream Freshwater and Terrestrial Sources Are Differentially Reflected in the Bacterial Community Structure along a Small Arctic River and Its Estuary

    Science.gov (United States)

    Hauptmann, Aviaja L.; Markussen, Thor N.; Stibal, Marek; Olsen, Nikoline S.; Elberling, Bo; Bælum, Jacob; Sicheritz-Pontén, Thomas; Jacobsen, Carsten S.

    2016-01-01

    Glacier melting and altered precipitation patterns influence Arctic freshwater and coastal ecosystems. Arctic rivers are central to Arctic water ecosystems by linking glacier meltwaters and precipitation with the ocean through transport of particulate matter and microorganisms. However, the impact of different water sources on the microbial communities in Arctic rivers and estuaries remains unknown. In this study we used 16S rRNA gene amplicon sequencing to assess a small river and its estuary on the Disko Island, West Greenland (69°N). Samples were taken in August when there is maximum precipitation and temperatures are high in the Disko Bay area. We describe the bacterial community through a river into the estuary, including communities originating in a glacier and a proglacial lake. Our results show that water from the glacier and lake transports distinct communities into the river in terms of diversity and community composition. Bacteria of terrestrial origin were among the dominating OTUs in the main river, while the glacier and lake supplied the river with water containing fewer terrestrial organisms. Also, more psychrophilic taxa were found in the community supplied by the lake. At the river mouth, the presence of dominant bacterial taxa from the lake and glacier was unnoticeable, but these taxa increased their abundances again further into the estuary. On average 23% of the estuary community consisted of indicator OTUs from different sites along the river. Environmental variables showed only weak correlations with community composition, suggesting that hydrology largely influences the observed patterns. PMID:27708629

  19. Upstream freshwater and terrestrial sources are differentially reflected in the bacterial community structure along a small Arctic river and its estuary

    Directory of Open Access Journals (Sweden)

    Aviaja Lyberth Hauptmann

    2016-09-01

    Full Text Available Glacier melting and altered precipitation patterns influence Arctic freshwater and coastal ecosystems. Arctic rivers are central to Arctic water ecosystems by linking glacier meltwaters and precipitation with the ocean through transport of particulate matter and microorganisms. However, the impact of different water sources on the microbial communities in Arctic rivers and estuaries remains unknown. In this study we used 16S rRNA gene amplicon sequencing to assess a small river and its estuary on the Disko Island, West Greenland (69°N. Samples were taken in August when there is maximum precipitation and temperatures are high in the Disko Bay area. We describe the bacterial community through a river into the estuary, including communities originating in a glacier and a proglacial lake. Our results show that water from the glacier and lake transports distinct communities into the river in terms of diversity and community composition. Bacteria of terrestrial origin were among the dominating OTUs in the main river, while the glacier and lake supplied the river with water containing fewer terrestrial organisms. Also, more psychrophilic taxa were found in the community supplied by the lake. At the river mouth, the presence of dominant bacterial taxa from the lake and glacier was unnoticeable, but these taxa increased their abundances again further into the estuary. On average 23% of the estuary community consisted of indicator OTUs from different sites along the river. Environmental variables showed only weak correlations with community composition, suggesting that hydrology largely influences the observed patterns.

  20. Researcher Interview: Tom Hudson

    Science.gov (United States)

    Tom Hudson, M.D., President and Scientific Director of the Ontario Institute for Cancer Research, describes the International Cancer Genome Consortium (ICGC), which brings together cancer genomic data and research from across the world.

  1. Changes of Benthic Macroinvertebrates in Thi Vai River and Cai Mep Estuaries Under Polluted Conditions with Industrial Wastewater

    Directory of Open Access Journals (Sweden)

    Huong Nguyen Thi Thanh

    2017-06-01

    Full Text Available The pollution on the Thi Vai River has been spreading out rapidly over the two lasted decades caused by the wastewater from the industrial parks in the left bank of Thi Vai River and Cai Mep Estuaries. The evaluation of the benthic macroinvertebrate changes was very necessary to identify the consequences of the industrial wastewater on water quality and aquatic ecosystem of Thi Vai River and Cai Mep Estuaries. In this study, the variables of benthic macroinvertebrates and water quality were investigated in Thi Vai River and Cai Mep Estuaries, Southern Vietnam. The monitoring data of benthic macroinvertebrates and water quality parameters covered the period from 1989 to 2015 at 6 sampling sites in Thi Vai River and Cai Mep Estuaries. The basic water quality parameters were also tested including pH, dissolved oxygen (DO, total nitrogen, and total phosphorus. The biodiversity indices of benthic macroinvertebrates were applied for water quality assessment. The results showed that pH ranged from 6.4 – 7.6 during the monitoring. The DO concentrations were in between 0.20 - 6.70 mg/L. The concentrations of total nitrogen and total phosphorous ranged from 0.03 - 5.70 mg/L 0.024 - 1.380 mg/L respectively. Macroinvertebrate community in the study area consisted of 36 species of polychaeta, gastropoda, bivalvia, and crustacea, of which, species of polychaeta were dominant in species number. The benthic macroinvertebartes density ranged from 0 - 2.746 individuals/m−1 with the main dominant species of Neanthes caudata, Prionospio malmgreni, Paraprionospio pinnata, Trichochaeta carica, Maldane sarsi, Capitella capitata, Terebellides stroemi, Euditylia polymorpha, Grandidierella lignorum, Apseudes vietnamensis. The biodiversity index values during the monitoring characterized for aquatic environmental conditions of mesotrophic to polytrophic. Besides, species richness positively correlated with DO, total nitrogen, and total phosphorus. The results

  2. Thermal impact assessment of multi power plant operations on estuaries

    International Nuclear Information System (INIS)

    Eraslan, A.H.; Kim, K.H.; Harris, J.L.

    1977-01-01

    The assessment of the thermal impact of multi power plant operations on large estuaries requires careful consideration of the problems associated with: re-entrainment, re-circulation, thermal interaction, delay in the attainment of thermal equilibrium state, and uncertainty in specifying open boundaries and open boundary conditions of the regions, which are critically important in the analysis of the thermal conditions in receiving water bodies with tidal dominated, periodically reversing flow conditions. The results of an extensive study in the Hudson River at Indian Point, 42 miles upstream of the ocean end at the Battery, concluded that the tidal-transient, multi-dimensional discrete-element (UTA) thermal transport models (ESTONE, FLOTWO, TMPTWO computer codes) and the near-field far-field zone-matching methodology can be employed with a high degree of reliability in the assessment of the thermal impact of multi power plant operations on tidal dominated estuaries

  3. A Numerical Modeling Study of Mesodinium Bloom Formation and Retention in a River-Dominated Mesotidal Estuary

    Science.gov (United States)

    Spitz, Y. H.; Cervantes, B.

    2016-02-01

    The Columbia River estuary experiences extensive seasonal red-colored blooms caused by a mixotrophic ciliate of the genus Mesodinium. Although the blooms are non-toxic, they have a significant influence on the levels of nutrients, light and oxygen in the estuary. Mesodinium spp. displays very particular physiology that makes it one of few planktonic species able to thrive in a highly flushed system: a high growth rate due to its ability to photosynthesize using the photosynthetic organelles of its preys, and complex vertical migration patterns. Knowledge of the migration pattern is based on limited observations of Mesodinium behavior in culture and recent in-situ measurements collected in the Columbia River estuary. A more comprehensive understanding is needed of the mechanisms allowing Mesodinium spp. to be retained and experience rapid growth. To this end, we extended the finite element circulation model SELFE to include a 5-component behavioral model that simulates the relationships between nutrients, detritus, Mesodinium spp. and its cryptophyte prey. We then used the model to investigate various migration patterns and growth scenarios to determine their role in the formation and retention of the Mesodinium spp. bloom in the brackish water of the estuary.

  4. Monitoring of persistent organic pollutants in seawater of the Pearl River Estuary with rapid on-site active SPME sampling technique

    International Nuclear Information System (INIS)

    Huang, Siming; He, Shuming; Xu, Hao; Wu, Peiyan; Jiang, Ruifen; Zhu, Fang; Luan, Tiangang; Ouyang, Gangfeng

    2015-01-01

    An on-site active solid-phase microextraction (SPME) sampling technique coupled with gas chromatography-mass spectrometry (GC–MS) for sampling and monitoring 16 polycyclic aromatic hydrocarbons (PAHs) and 8 organochlorine pesticides (OCPs) in seawater was developed. Laboratory experiments demonstrated that the sampling-rate calibration method was practical and could be used for the quantification of on-site sampling. The proposed method was employed for field tests which covered large amounts of water samples in the Pearl River Estuary in rainy and dry seasons. The on-site SPME sampling method can avoid the contamination of sample, the losses of analytes during sample transportation, as well as the usage of solvent and time-consuming sample preparation process. Results indicated that the technique with the designed device can address the requirement of modern environment water analysis. In addition, the sources, bioaccumulation and potential risk to human of the PAHs and OCPs in seawater of the Pearl River Estuary were discussed. - Highlights: • SPME on-site active sampling technique was developed and validated. • The technique was employed for field tests in the Pearl River Estuary. • 16 PAHs and 8 OCPs in the seawater of Pearl River Estuary were monitored. • The potential risk of the PAHs and OCPs in Pearl River Estuary were discussed. - An on-site active SPME sampling technique was developed and successfully applied for sampling and monitoring 16 PAHs and 8 OCPs in the Pearl River Estuary

  5. 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

  6. Milwaukee Estuary AOC

    Science.gov (United States)

    The rivers in the Milwaukee estuary in Wisconsin drain into Lake Michigan. Wastewater treatment plants and combined sewer overflows contribute pollution which affects fish and wildlife and recreation.

  7. Multi-Scale Action Effectiveness Research in the Lower Columbia River and Estuary, 2011 - FINAL ANNUAL REPORT

    Energy Technology Data Exchange (ETDEWEB)

    Sather, Nichole K.; Storch, Adam; Johnson, Gary E.; Teel, D. J.; Skalski, J. R.; Bryson, Amanda J.; Kaufmann, Ronald M.; Woodruff, Dana L.; Blaine, Jennifer; Kuligowski, D. R.; Kropp, Roy K.; Dawley, Earl M.

    2012-05-31

    The study reported here was conducted by researchers at Pacific Northwest National Laboratory (PNNL), the Oregon Department of Fish and Wildlife (ODFW), the University of Washington (UW), and the National Marine Fisheries Service (NMFS) for the U.S. Army Corps of Engineers, Portland District (USACE). This research project was initiated in 2007 by the Bonneville Power Administration to investigate critical uncertainties regarding juvenile salmon ecology in shallow tidal freshwater habitats of the lower Columbia River. However, as part of the Washington Memorandum of Agreement, the project was transferred to the USACE in 2010. In transferring from BPA to the USACE, the focus of the tidal freshwater research project shifted from fundamental ecology toward the effectiveness of restoration in the Lower Columbia River and estuary (LCRE). The research is conducted within the Action Agencies Columbia Estuary Ecosystem Restoration Program (CEERP). Data reported herein spans the time period May 2010 to September 2011.

  8. Resuspension and estuarine nutrient cycling: insights from the Neuse River Estuary

    Directory of Open Access Journals (Sweden)

    D. R. Corbett

    2010-10-01

    Full Text Available For at least the past several decades, North Carolina's Neuse River Estuary (NRE has been subject to water quality problems relating to increased eutrophication. Research initiated in the past several years have addressed the nutrient processes of the water column and the passive diffusion processes of the benthic sedimentary environment. Resuspension of bottom sediments, by bioturbation, tides, or winds, may also have a significant effect on the flux of nutrients in an estuarine system These processes can result in the advective transport of sediment porewater, rich with nitrogen, phosphorus and carbon, into the water column. Thus, estimates of nutrient and carbon inputs from the sediments may be too low.

    This study focused on the potential change in bottom water nutrient concentrations associated with measured resuspension events. Previous research used short-lived radionuclides and meteorological data to characterize the sediment dynamics of the benthic system of the estuary. These techniques in conjunction with the presented porewater inventories allowed evaluation of the depth to which sediments have been disturbed and the advective flux of nutrients to the water column. The largest removal episode occurred in the lower NRE as the result of a wind event and was estimated that the top 2.2 cm of sediment and corresponding porewater were removed. NH4+ advective flux (resuspended was 2 to 6 times greater than simply diffusion. Phosphate fluxes were estimated to be 15 times greater than the benthic diffusive flux. Bottom water conditions with elevated NH4+ and PO43− indicate that nutrients stored in the sediments continue to play an important role in overall water quality and this study suggests that the advective flux of nutrients to the water column is critical to understand estuarine nutrient cycling.

  9. Migratory Behavior and Survival of Juvenile Salmonids in the Lower Columbia River, Estuary, and Plume in 2010

    Energy Technology Data Exchange (ETDEWEB)

    McMichael, Geoffrey A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Harnish, Ryan A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Skalski, John R. [Univ. of Washington, Seattle, WA (United States); Deters, Katherine A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ham, Kenneth D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Townsend, Richard L. [Univ. of Washington, Seattle, WA (United States); Titzler, P. Scott [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hughes, Michael S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kim, Jin A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Trott, Donna M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2011-09-01

    Uncertainty regarding the migratory behavior and survival of juvenile salmonids passing through the lower Columbia River and estuary after negotiating dams on the Federal Columbia River Power System (FCRPS) prompted the development and application of the Juvenile Salmon Acoustic Telemetry System (JSATS). The JSATS has been used to investigate the survival of juvenile salmonid smolts between Bonneville Dam (river kilometer (rkm) 236) and the mouth of the Columbia River annually since 2004. In 2010, a total of 12,214 juvenile salmonids were implanted with both a passive integrated transponder (PIT) and a JSATS acoustic transmitter. Using detection information from JSATS receiver arrays deployed on dams and in the river, estuary, and plume, the survival probability of yearling Chinook salmon and steelhead smolts tagged at John Day Dam was estimated form multiple reaches between rkm 153 and 8.3 during the spring. During summer, the survival probability of subyearling Chinook salmon was estimated for the same reaches. In addition, the influence of routes of passage (e.g., surface spill, deep spill, turbine, juvenile bypass system) through the lower three dams on the Columbia River (John Day, The Dalles, and Bonneville) on juvenile salmonid smolt survival probability from the dams to rkm 153 and then between rkm 153 and 8.3 was examined to increase understanding of the immediate and latent effects of dam passage on juvenile salmon survival. Similar to previous findings, survival probability was relatively high (>0.95) for most groups of juvenile salmonids from the Bonneville Dam tailrace to about rkm 50. Downstream of rkm 50 the survival probability of all species and run types we examined decreased markedly. Steelhead smolts suffered the highest mortality in this lower portion of the Columbia River estuary, with only an estimated 60% of the tagged fish surviving to the mouth of the river. In contrast, yearling and subyearling Chinook salmon smolts survived to the mouth

  10. Larval fish composition and spatio-temporal variation in the estuary of Pendas River, southwestern Johor, Peninsular Malaysia

    OpenAIRE

    Arshad, Aziz Bin; Ara, Roushon; Amin, S. M. Nurul; Daud, Siti Khalijah; Ghaffar, Mazlan Abdul

    2012-01-01

    The temporal and spatial patterns of family composition and abundance of fish larvae in the Pendas River mangrove estuary (Southwestern Johor) of Peninsular Malaysia was studied monthly using bongo net in daylight sampling. Environmental factors viz., water temperature, salinity, dissolved oxygen, pH and conductivity were also monitored during sampling. In total 2687 individuals representing 19 families were collected during 12 months study period (October 2007 to September 2008). The larval ...

  11. Weight-of-evidence approach in assessment of ecotoxicological risks of acid sulphate soils in the Baltic Sea river estuaries

    Energy Technology Data Exchange (ETDEWEB)

    Wallin, Jaana, E-mail: jaana.wallin@jyu.fi [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland); Karjalainen, Anna K. [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland); Schultz, Eija [Finnish Environment Institute SYKE, Hakuninmaantie 6, FI-00430 Helsinki (Finland); Järvistö, Johanna; Leppänen, Matti; Vuori, Kari-Matti [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland)

    2015-03-01

    Acidity and leaching of metals from acid sulphate soils (ASSs) impair the water quality of receiving surface waters. The largest ASS areas in Europe are found in the coasts of the northern Baltic Sea. We used weight-of-evidence (WoE) approach to assess potential risks in 14 estuary sites affected by ASS in the Gulf of Finland, northern Baltic Sea. The assessment was based on exposure and effect profiles utilizing sediment and water metal concentrations and concurrent pH variation, sediment toxicity tests using the luminescent bacterium Vibrio fischeri and the midge Chironomus riparius, and the ecological status of benthic macroinvertebrate communities. Sediment metal concentrations were compared to national sediment quality criteria/guidelines, and water metal concentrations to environmental quality standards (EQSs). Hazard quotients (HQs) were established for maximum aluminium, cadmium and zinc concentrations at low pH based on applicable US EPA toxicity database. Sediment metal concentrations were clearly elevated in most of the studied estuaries. The EQS of cadmium (0.1 μg/l) was exceeded in 3 estuaries out of 14. The pH-minima were below the national threshold value (5.5) between good and satisfactory water quality in 10 estuaries. V. fischeri bioluminescence indicated toxicity of the sediments but toxic response was not observed in the C. riparius emergence test. Benthic invertebrate communities were deteriorated in 6 out of 14 sites based on the benthic invertebrate quality index. The overall ecotoxicological risk was assessed as low in five, moderate in three and high in five of the estuary sites. The risk assessment utilizing the WoE approach indicated that harmful effects of ASSs are likely to occur in the Baltic Sea river estuaries located at the ASS hotspot area. - Highlights: • Acid sulphate soils release high amounts of metals and acidity. • Metals and acidity are transported to estuary sites. • Acid sulphate soils impair the ecological status

  12. Salmon Life Histories, Habitat, and Food Webs in the Columbia River Estuary: An Overview of Research Results, 2002-2006.

    Energy Technology Data Exchange (ETDEWEB)

    Bottom, Daniel L.; Anderson, Greer; Baptisa, Antonio

    2008-08-01

    From 2002 through 2006 we investigated historical and contemporary variations in juvenile Chinook salmon Oncorhynchus tshawytscha life histories, habitat associations, and food webs in the lower Columbia River estuary (mouth to rkm 101). At near-shore beach-seining sites in the estuary, Chinook salmon occurred during all months of the year, increasing in abundance from January through late spring or early summer and declining rapidly after July. Recently emerged fry dispersed throughout the estuary in early spring, and fry migrants were abundant in the estuary until April or May each year. Each spring, mean salmon size increased from the tidal freshwater zone to the estuary mouth; this trend may reflect estuarine growth and continued entry of smaller individuals from upriver. Most juvenile Chinook salmon in the mainstem estuary fed actively on adult insects and epibenthic amphipods Americorophium spp. Estimated growth rates of juvenile Chinook salmon derived from otolith analysis averaged 0.5 mm d-1, comparable to rates reported for juvenile salmon Oncorhynchus spp. in other Northwest estuaries. Estuarine salmon collections were composed of representatives from a diversity of evolutionarily significant units (ESUs) from the lower and upper Columbia Basin. Genetic stock groups in the estuary exhibited distinct seasonal and temporal abundance patterns, including a consistent peak in the Spring Creek Fall Chinook group in May, followed by a peak in the Western Cascades Fall Chinook group in July. The structure of acanthocephalan parasite assemblages in juvenile Chinook salmon from the tidal freshwater zone exhibited a consistent transition in June. This may have reflected changes in stock composition and associated habitat use and feeding histories. From March through July, subyearling Chinook salmon were among the most abundant species in all wetland habitat types (emergent, forested, and scrub/shrub) surveyed in the lower 100 km of the estuary. Salmon densities

  13. Upstream Freshwater and Terrestrial Sources Are Differentially Reflected in the Bacterial Community Structure along a Small Arctic River and Its Estuary

    DEFF Research Database (Denmark)

    Hauptmann, Aviaja Zenia Edna Lyberth; Markussen, Thor N; Stibal, Marek

    2016-01-01

    of different water sources on the microbial communities in Arctic rivers and estuaries remains unknown. In this study we used 16S rRNA gene amplicon sequencing to assess a small river and its estuary on the Disko Island, West Greenland (69°N). Samples were taken in August when there is maximum precipitation......Glacier melting and altered precipitation patterns influence Arctic freshwater and coastal ecosystems. Arctic rivers are central to Arctic water ecosystems by linking glacier meltwaters and precipitation with the ocean through transport of particulate matter and microorganisms. However, the impact...... and temperatures are high in the Disko Bay area. We describe the bacterial community through a river into the estuary, including communities originating in a glacier and a proglacial lake. Our results show that water from the glacier and lake transports distinct communities into the river in terms of diversity...

  14. [Effects of Long-term Implementation of the Flow-Sediment Regulation Scheme on Grain and Clay Compositions of Inshore Sediments in the Yellow River Estuary].

    Science.gov (United States)

    Wang, Miao-miao; Sun, Zhi-gao; Lu, Xiao-ning; Wang, Wei; Wang, Chuan-yuan

    2015-04-01

    Based on the laser particle size and X-ray diffraction (XRD) analysis, 28 sediment samples collected from the inshore region of the Yellow River estuary in October 2013 were determined to discuss the influence of long-term implementation of the flow-sediment regulation scheme (FSRS, initiated in 2002) on the distributions of grain size and clay components (smectite, illite, kaolinite and chlorite) in sediments. Results showed that, after the FSRS was implemented for more than 10 years, although the proportion of sand in inshore sediments of the Yellow River estuary was higher (average value, 23.5%) than those in sediments of the Bohai Sea and the Yellow River, silt was predominated (average value, 59.1%) and clay components were relatively low (average value, 17.4%). The clay components in sediments of the inshore region in the Yellow River estuary were close with those in the Yellow River. The situation was greatly changed due to the implementation of FSRS since 2002, and the clay components were in the order of illite > smectite > chlorite > kaolinite. This study also indicated that, compared to large-scale investigation in Bohai Sea, the local study on the inshore region of the Yellow River estuary was more favorable for revealing the effects of long-term implementation of the FSRS on sedimentation environment of the Yellow River estuary.

  15. Massive production of heavy metals in the Ganga (Hooghly) River estuary, India: Global importance of solute-particle interaction and enhanced metal fluxes to the oceans

    Science.gov (United States)

    Samanta, Saumik; Dalai, Tarun K.

    2018-05-01

    The Ganga River System is a major contributor to the global sediment and water discharge to the oceans. The estuary of Ganga (Hooghly) River in India is under increasing influence of anthropogenic contributions via discharge of the industrial and urban effluents. Here we document, based on the investigation of water and suspended sediment samples collected during six periods over two years, that there is extensive production of heavy metals (Co, Ni and Cu) in the estuary such that the annual dissolved fluxes of metals from the Hooghly River are enhanced by up to 230-1770%. Furthermore, the estuarine dissolved metal fluxes, when normalized with water fluxes, are the highest among estuaries of the major rivers in the world. Our simultaneous data on the dissolved, suspended particulate and exchangeable phases allow us to identify the ion-exchange process (coupled adsorption and desorption) as the dominant contributor to the generation of heavy metals in the middle and lower estuary where the estimated anthropogenic contribution is negligible. The estimated contributions from the groundwater are also insufficient to explain the measured metal concentrations in the estuary. A strong positive correlation that is observed between the dissolved heavy metal fluxes and the suspended particulate matter (SPM) fluxes, after normalizing them with the water fluxes, for estuaries of the major global rivers imply that the solute-particle interaction is a globally significant process in the estuarine production of metals. Based on this correlation that is observed for major estuaries around the world, we demonstrate that the South Asian Rivers which supply only ∼9% of the global river water discharge but carry elevated SPM load, contribute a far more significant proportion (∼40 ± 2% Ni and 15 ± 1% Cu) to the global supply of the dissolved metals from the rivers.

  16. A network model shows the importance of coupled processes in the microbial N cycle in the Cape Fear River Estuary

    Science.gov (United States)

    Hines, David E.; Lisa, Jessica A.; Song, Bongkeun; Tobias, Craig R.; Borrett, Stuart R.

    2012-06-01

    Estuaries serve important ecological and economic functions including habitat provision and the removal of nutrients. Eutrophication can overwhelm the nutrient removal capacity of estuaries and poses a widely recognized threat to the health and function of these ecosystems. Denitrification and anaerobic ammonium oxidation (anammox) are microbial processes responsible for the removal of fixed nitrogen and diminish the effects of eutrophication. Both of these microbial removal processes can be influenced by direct inputs of dissolved inorganic nitrogen substrates or supported by microbial interactions with other nitrogen transforming pathways such as nitrification and dissimilatory nitrate reduction to ammonium (DNRA). The coupling of nitrogen removal pathways to other transformation pathways facilitates the removal of some forms of inorganic nitrogen; however, differentiating between direct and coupled nitrogen removal is difficult. Network modeling provides a tool to examine interactions among microbial nitrogen cycling processes and to determine the within-system history of nitrogen involved in denitrification and anammox. To examine the coupling of nitrogen cycling processes, we built a nitrogen budget mass balance network model in two adjacent 1 cm3 sections of bottom water and sediment in the oligohaline portion of the Cape Fear River Estuary, NC, USA. Pathway, flow, and environ ecological network analyses were conducted to characterize the organization of nitrogen flow in the estuary and to estimate the coupling of nitrification to denitrification and of nitrification and DNRA to anammox. Centrality analysis indicated NH4+ is the most important form of nitrogen involved in removal processes. The model analysis further suggested that direct denitrification and coupled nitrification-denitrification had similar contributions to nitrogen removal while direct anammox was dominant to coupled forms of anammox. Finally, results also indicated that partial

  17. [Spectral absorption properties of the water constituents in the estuary of Zhujiang River].

    Science.gov (United States)

    Wang, Shan-shan; Wang, Yong-bo; Fu, Qing-hua; Yin, Bin; Li, Yun-mei

    2014-12-01

    Spectral absorption properties of the water constituents is the main factor affecting the light field under the surface of the water and the spectrum above the surface of the water. Thus, the study is useful for understanding of the water spectral property and the remote reversing of water quality parameters. Absorption properties of total suspended particles, non-algal particles, phytoplankton and CDOM were analyzed using the 30 samples collected in July 2013 in the estuary of Zhujiang River. The results indicated that: (1) the non-algal particles absorption dominated the absorption of the total suspended particles; (2) the absorption coefficient of the non-algal particles, which mainly came from the terrigenous deposits, decreased exponentially from short to long wavelength. In addition, the average value and spatial variation of the slope S(d) were higher than those in inland case- II waters; (3) the absorption coefficient of phytoplankton in 440 nm showed a better polynomial relationship with chlorophyll a concentration, while the absorption coefficient of phytoplankton in 675 nm linearly related with the chlorophyll a concentration. Moreover, the influence of accessory pigments on phytoplankton absorption coefficient mainly existed in the range of short wavelength, and Chlorophyll a was the main influencing factor for phytoplankton absorption in long wavelength. The specific absorption coefficient of phytoplankton decreased the power exponentially with the increase of the chlorophyll a concentration; (4) CDOM mainly came from the terrigenous sources and its spectral curve had an absorption shoulder between 250-290 nm. Thus, a piecewise S(g) fitting function could effectively express CDOM absorption properties, i.e., M value and S(g) value in period A (240-260 nm) showed a strong positive correlation. The M value was low, and the humic acid had a high proportion in CDOM; (5) the non-algal particles absorption dominated the total absorption in the estuary of

  18. Estimation of low-flow statistics at ungaged sites on streams in the Lower Hudson River Basin, New York, from data in geographic information systems

    Science.gov (United States)

    Randall, Allan D.; Freehafer, Douglas A.

    2017-08-02

    A variety of watershed properties available in 2015 from geographic information systems were tested in regression equations to estimate two commonly used statistical indices of the low flow of streams, namely the lowest flows averaged over 7 consecutive days that have a 1 in 10 and a 1 in 2 chance of not being exceeded in any given year (7-day, 10-year and 7-day, 2-year low flows). The equations were based on streamflow measurements in 51 watersheds in the Lower Hudson River Basin of New York during the years 1958–1978, when the number of streamflow measurement sites on unregulated streams was substantially greater than in subsequent years. These low-flow indices are chiefly a function of the area of surficial sand and gravel in the watershed; more precisely, 7-day, 10-year and 7-day, 2-year low flows both increase in proportion to the area of sand and gravel deposited by glacial meltwater, whereas 7-day, 2-year low flows also increase in proportion to the area of postglacial alluvium. Both low-flow statistics are also functions of mean annual runoff (a measure of net water input to the watershed from precipitation) and area of swamps and poorly drained soils in or adjacent to surficial sand and gravel (where groundwater recharge is unlikely and riparian water loss to evapotranspiration is substantial). Small but significant refinements in estimation accuracy resulted from the inclusion of two indices of stream geometry, channel slope and length, in the regression equations. Most of the regression analysis was undertaken with the ordinary least squares method, but four equations were replicated by using weighted least squares to provide a more realistic appraisal of the precision of low-flow estimates. The most accurate estimation equations tested in this study explain nearly 84 and 87 percent of the variation in 7-day, 10-year and 7-day, 2-year low flows, respectively, with standard errors of 0.032 and 0.050 cubic feet per second per square mile. The equations

  19. Tracing the origin of the oxygen-consuming organic matter in the hypoxic zone in a large eutrophic estuary: the lower reach of the Pearl River Estuary, China

    Directory of Open Access Journals (Sweden)

    J. Su

    2017-09-01

    Full Text Available We assess the relative contributions of different sources of organic matter, marine vs. terrestrial, to oxygen consumption in an emerging hypoxic zone in the lower Pearl River Estuary (PRE, a large eutrophic estuary located in Southern China. Our cruise, conducted in July 2014, consisted of two legs before and after the passing of Typhoon Rammasun, which completely de-stratified the water column. The stratification recovered rapidly, within 1 day after the typhoon. We observed algal blooms in the upper layer of the water column and hypoxia underneath in bottom water during both legs. Repeat sampling at the initial hypoxic station showed severe oxygen depletion down to 30 µmol kg−1 before the typhoon and a clear drawdown of dissolved oxygen after the typhoon. Based on a three endmember mixing model and the mass balance of dissolved inorganic carbon and its isotopic composition, the δ13C of organic carbon remineralized in the hypoxic zone was −23.2 ± 1.1 ‰. We estimated that 65 ± 16 % of the oxygen-consuming organic matter was derived from marine sources, and the rest (35 ± 16 % was derived from the continent. In contrast to a recently studied hypoxic zone in the East China Sea off the Changjiang Estuary where marine organic matter dominated oxygen consumption, here terrestrial organic matter significantly contributed to the formation and maintenance of hypoxia. How varying amounts of these organic matter sources drive oxygen consumption has important implications for better understanding hypoxia and its mitigation in bottom waters.

  20. Geographic specificity of Aroclor 1268 in bottlenose dolphins (Tursiops truncatus) frequenting the Turtle/Brunswick River Estuary, Georgia (USA)

    International Nuclear Information System (INIS)

    Pulster, Erin L.; Maruya, Keith A.

    2008-01-01

    Coastal marine resources are at risk from anthropogenic contaminants, including legacy persistent organic pollutants (POPs) with half-lives of decades or more. To determine if polychlorinated biphenyl (PCB) signatures can be used to distinguish among local populations of inshore bottlenose dolphins (Tursiops truncatus) along the southeastern U.S. coast, blubber from free-ranging and stranded animals were collected along the Georgia coast in 2004 and analyzed for PCB congeners using gas chromatography with electron capture and negative chemical ionization mass spectrometric detection (GC-ECD and GC-NCI-MS). Mean total PCB concentrations (77 ± 34 μg/g lipid) were more than 10 fold higher and congener distributions were highly enriched in Cl 7 -Cl 10 homologs in free-ranging animals from the Turtle/Brunswick River estuary (TBRE) compared with strandings samples from Savannah area estuaries 90 km to the north. Using principal components analysis (PCA), the Aroclor 1268 signature associated with TBRE animals was distinct from that observed in Savannah area animals, and also from those in animals biopsied in other southeastern U.S estuaries. Moreover, PCB signatures in dolphin blubber closely resembled those in local preferred prey fish species, strengthening the hypothesis that inshore T. truncatus populations exhibit long-term fidelity to specific estuaries and making them excellent sentinels for assessing the impact of stressors on coastal ecosystem health

  1. Climatic variability and its role in regulating C, N and P retention in the James River Estuary

    Science.gov (United States)

    Bukaveckas, Paul A.; Beck, Michael; Devore, Dana; Lee, William M.

    2018-05-01

    Transformations and retention of C, N and P inputs to estuaries are subject to external factors such as discharge-driven variation in loading rates, and internal processes regulating biogeochemical cycles. We used an 8-year time series of finely resolved (monthly) mass balances for the tidal freshwater segment of the James River Estuary to assess the influence of discharge and temperature on C, N and P retention. Peak export and retention of organic, likely particulate, fractions occurred in months of highest discharge. With increasing discharge we observed higher mass retention, greater proportional retention (in relation to inputs) and more selective retention (with P retained preferentially over N and C). DIN retention was strongly influenced by water temperature with 10-fold high retention occurring at high (>20 °C) vs. low (estuaries is in dissolved inorganic form, and therefore subject to temperature dependent rates of biological assimilation and denitrification. By contrast, the bulk of the P load was in particulate form, which is retained via sediment trapping, and not appreciably affected by water temperature. The tidal freshwater estuary was an important site for nutrient removal where the accumulation of N- and P- rich materials may delay recovery in response to nutrient load reductions.

  2. Spatial-temporal distribution and risk assessment of mercury in different fractions in surface sediments from the Yangtze River estuary.

    Science.gov (United States)

    Wang, Qingrui; Liu, Ruimin; Men, Cong; Xu, Fei; Guo, Lijia; Shen, Zhenyao

    2017-11-15

    The temporal and spatial distributions of mercury in different fractions and its potential ecological risk were investigated in sediments from the Yangtze River estuary (YRE) by analyzing data collected from the study area. The results showed that mercury in the organic and residual fractions had dominant proportions, from 15.2% to 48.52% and from 45.96% to 81.59%, respectively. The fractions were more susceptible to seasonal changes than other fractions. Higher proportions of mercury in organic fraction were found in wet seasons; the opposite was true for mercury in residual fraction. With respect to the spatial distribution, the concentration mercury in exchangeable, carbonate and Fe-Mn oxide fractions showed a decreasing trend from the inner estuary to the outer estuary, but no obvious trends were found in the distributions of mercury in the organic and residual fractions. The risk assessment code (RAC) was used to evaluate the potential ecological risk in the study area based on the proportions of exchangeable and carbonate fractions. The average RAC values during the four periods were 6.00%, 2.20%, 2.83%, and 0.61%. Although these values show that the risk in the study area is generally low, the distribution of RAC values indicates that the inner estuary has a medium risk, with a value up to 10%. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Geographic specificity of Aroclor 1268 in bottlenose dolphins (Tursiops truncatus) frequenting the Turtle/Brunswick River Estuary, Georgia (USA)

    Energy Technology Data Exchange (ETDEWEB)

    Pulster, Erin L. [Marine Sciences Department, Savannah State University, Savannah, Georgia, 31404 (United States); Skidaway Institute of Oceanography, 10 Ocean Science Circle, Savannah, Georgia, 31411 (United States)], E-mail: epulster@mote.org; Maruya, Keith A. [Skidaway Institute of Oceanography, 10 Ocean Science Circle, Savannah, Georgia, 31411 (United States)

    2008-04-15

    Coastal marine resources are at risk from anthropogenic contaminants, including legacy persistent organic pollutants (POPs) with half-lives of decades or more. To determine if polychlorinated biphenyl (PCB) signatures can be used to distinguish among local populations of inshore bottlenose dolphins (Tursiops truncatus) along the southeastern U.S. coast, blubber from free-ranging and stranded animals were collected along the Georgia coast in 2004 and analyzed for PCB congeners using gas chromatography with electron capture and negative chemical ionization mass spectrometric detection (GC-ECD and GC-NCI-MS). Mean total PCB concentrations (77 {+-} 34 {mu}g/g lipid) were more than 10 fold higher and congener distributions were highly enriched in Cl{sub 7}-Cl{sub 10} homologs in free-ranging animals from the Turtle/Brunswick River estuary (TBRE) compared with strandings samples from Savannah area estuaries 90 km to the north. Using principal components analysis (PCA), the Aroclor 1268 signature associated with TBRE animals was distinct from that observed in Savannah area animals, and also from those in animals biopsied in other southeastern U.S estuaries. Moreover, PCB signatures in dolphin blubber closely resembled those in local preferred prey fish species, strengthening the hypothesis that inshore T. truncatus populations exhibit long-term fidelity to specific estuaries and making them excellent sentinels for assessing the impact of stressors on coastal ecosystem health.

  4. Diet and trophic organization of the fish assemblage from the Mamanguape River Estuary, Brazil

    OpenAIRE

    Medeiros, Aline Paiva Morais de; Xavier, Josias Henrique de Amorim; Rosa, Ierecê Maria de Lucena

    2017-01-01

    ABSTRACT The present work aims to characterize a fish assemblage from a northeastern Brazilian estuary according to its diet and trophic organization along the estuarine-reef gradient. Sampling was performed at the Mamanguape Estuary, and fishes were collected using three types of nets at seventeen sites, grouped into four regions according to salinity range: reefs and the lower, middle, and upper estuary. The most abundant species were Atherinella brasiliensis, Mugil curema, and Sphoeroides ...

  5. Estuarine Habitats for Juvenile Salmon in the Tidally-Influenced Lower Columbia River and Estuary : Reporting Period September 15, 2008 through May 31, 2009.

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, António M. [Oregon Health & Science University, Science and Technology Center for Coastal Margin Observation and Prediction

    2009-08-02

    This work focuses on the numerical modeling of Columbia River estuarine circulation and associated modeling-supported analyses conducted as an integral part of a multi-disciplinary and multi-institutional effort led by NOAA's Northwest Fisheries Science Center. The overall effort is aimed at: (1) retrospective analyses to reconstruct historic bathymetric features and assess effects of climate and river flow on the extent and distribution of shallow water, wetland and tidal-floodplain habitats; (2) computer simulations using a 3-dimensional numerical model to evaluate the sensitivity of salmon rearing opportunities to various historical modifications affecting the estuary (including channel changes, flow regulation, and diking of tidal wetlands and floodplains); (3) observational studies of present and historic food web sources supporting selected life histories of juvenile salmon as determined by stable isotope, microchemistry, and parasitology techniques; and (4) experimental studies in Grays River in collaboration with Columbia River Estuary Study Taskforce (CREST) and the Columbia Land Trust (CLT) to assess effects of multiple tidal wetland restoration projects on various life histories of juvenile salmon and to compare responses to observed habitat-use patterns in the mainstem estuary. From the above observations, experiments, and additional modeling simulations, the effort will also (5) examine effects of alternative flow-management and habitat-restoration scenarios on habitat opportunity and the estuary's productive capacity for juvenile salmon. The underlying modeling system is part of the SATURN1coastal-margin observatory [1]. SATURN relies on 3D numerical models [2, 3] to systematically simulate and understand baroclinic circulation in the Columbia River estuary-plume-shelf system [4-7] (Fig. 1). Multi-year simulation databases of circulation are produced as an integral part of SATURN, and have multiple applications in understanding estuary

  6. Acoustic tag detections of green sturgeon in the Columbia River and Coos Bay estuaries, Washington and Oregon, 2010–11

    Science.gov (United States)

    Hansel, Hal C.; Romine, Jason G.; Perry, Russell W.

    2017-11-08

    The Columbia River, in Washington and Oregon, and Coos Bay, in Oregon, are economically important shipping channels that are inhabited by several fishes protected under the Endangered Species Act (ESA). Maintenance of shipping channels involves dredge operations to maintain sufficient in-channel depths to allow large ships to navigate the waterways safely. Fishes entrained by dredge equipment often die or experience delayed mortality. Other potential negative effects of dredging include increased turbidity, reductions in prey resources, and the release of harmful contaminants from the dredged sediments. One species of concern is the ESA-listed green sturgeon (Acipenser medirostris; Southern Distinct Population Segment). In this study, we used acoustic telemetry to identify habitat use, arrival and departure timing, and the extent of upstream migration of green sturgeon in the Columbia River and Coos Bay to help inform dredge operations to minimize potential take of green sturgeon. Autonomous acoustic receivers were deployed in Coos Bay from the mouth to river kilometer (rkm) 21.6 from October 2009 through October 2010. In the Columbia River Estuary, receivers were deployed between the mouth and rkm 37.8 from April to November in 2010 and 2011. A total of 29 subadult and adult green sturgeon were tagged with temperature and pressure sensor tags and released during the study, primarily in Willapa Bay and Grays Harbor, Washington, and the Klamath River, Oregon. Green sturgeon detected during the study but released by other researchers also were included in the study.The number of tagged green sturgeon detected in the two estuaries differed markedly. In Coos Bay, only one green sturgeon was detected for about 2 hours near the estuary mouth. In the Columbia River Estuary, 9 green sturgeon were detected in 2010 and 10 fish were detected in 2011. Green sturgeon entered the Columbia River from May through October during both years, with the greatest numbers of fish being

  7. Mixing and photoreactivity of dissolved organic matter in the Nelson/Hayes estuarine system (Hudson Bay, Canada)

    Science.gov (United States)

    Guéguen, C.; Mokhtar, M.; Perroud, A.; McCullough, G.; Papakyriakou, T.

    2016-09-01

    This work presents the results of a 4-year study (2009-2012) investigating the mixing and photoreactivity of dissolved organic matter (DOM) in the Nelson/Hayes estuary (Hudson Bay). Dissolved organic carbon (DOC), colored DOM, and humic-like DOM decreased with increasing salinity (r2 = 0.70-0.84). Removal of DOM was noticeable at low to mid salinity range, likely due to degradation and/or adsorption to particles. DOM photobleaching rates (i.e., decrease in DOM signal resulting from exposure to solar radiation) ranged from 0.005 to 0.030 h- 1, corresponding to half-lives of 4.9-9.9 days. Dissolved organic matter from the Nelson and Hayes Rivers was more photoreactive than from the estuary where the photodegradation of terrestrial DOM decreased with increasing salinity. Coincident with the loss of CDOM absorption was an increase in spectral slope S, suggesting a decrease in DOM molecular weight. Marked differences in photoreactivity of protein- and humic-like DOM were observed with highly humidified material being the most photosensitive. Information generated by our study will provide a valuable data set for better understanding the impacts of future hydroelectric development and climate change on DOM biogeochemical dynamics in the Nelson/Hayes estuary and coastal domain. This study will constitute a reference on terrestrial DOM fate prior to building additional generating capacity on the Nelson River.

  8. Organophosphorus flame retardants in mangrove sediments from the Pearl River Estuary, South China.

    Science.gov (United States)

    Hu, Yong-Xia; Sun, Yu-Xin; Li, Xiao; Xu, Wei-Hai; Zhang, Ying; Luo, Xiao-Jun; Dai, Shou-Hui; Xu, Xiang-Rong; Mai, Bi-Xian

    2017-08-01

    Forty-eight surface sediments were collected from three mangrove wetlands in the Pearl River Estuary (PRE) of South China to investigate the distribution of organophosphorus flame retardants (OPFRs) and the relationship between OPFRs and microbial community structure determined by phospholipid fatty acid. Concentrations of ΣOPFRs in mangrove sediments of the PRE ranged from 13.2 to 377.1 ng g -1 dry weight. Levels of ΣOPFRs in mangrove sediments from Shenzhen and Guangzhou were significantly higher than those from Zhuhai, indicating that OPFRs were linked to industrialization and urbanization. Tris(chloropropyl)phosphate was the predominant profile of OPFRs in mangrove sediments from Shenzhen (38.9%) and Guangzhou (35.0%), while the composition profile of OPFRs in mangrove sediments from Zhuhai was dominated by tris(2-chloroethyl) phosphate (25.5%). The mass inventories of OPFRs in the mangrove sediments of Guangzhou, Zhuhai and Shenzhen were 439.5, 133.5 and 662.3 ng cm -2 , respectively. Redundancy analysis revealed that OPFRs induced a shift in the structure of mangrove sediment microbial community and the variations were significantly correlated with tris(1,3-dichloro-2-propyl)phosphate and tris(2-butoxyethyl) phosphate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. [Health assessment of Qi'ao Island mangrove wetland ecosystem in Pearl River Estuary].

    Science.gov (United States)

    Wang, Shu-Gong; Zheng, Yao-Hui; Peng, Yi-Sheng; Chen, Gui-Zhu

    2010-02-01

    Based on the theories of wetland ecosystem health and by using "Pressure-State-Response" model, a health assessment indicator system for Qi' ao Island mangrove wetland ecosystem in Pearl River Estuary was built, and the assessment indices, assessment criteria, indices weighted values, assessment grades, and assessment methods were established to assess the health state of this ecosystem. In 2008, the overall health index of this ecosystem was 0.6580, health level was of grade II (healthy), and the pressure, state, and response indices were 0.3469, 0.8718, and 0.7754, respectively, suggesting that this ecosystem was good in state and response, but still had definite pressure. As a provincial nature reserve, this ecosystem was to be further improved in its health level. However, the research on the health assessment of mangrove wetland ecosystem was still young. Further studies should be made on the selection of assessment indices, long-term oriented monitoring of these indices, and quantification of the relations between ecosystem health level and ecosystem services.

  10. Characterization of phosphorus sorption on the sediments of Yangtze River Estuary and its adjacent areas

    International Nuclear Information System (INIS)

    Cao, Xiaoyan; Liu, Xiaoyue; Zhu, Jiamei; Wang, Lisha; Liu, Sumei; Yang, Guipeng

    2017-01-01

    This paper studied the kinetics, isotherm and thermodynamics of phosphorus sorption onto the sediments of the Yangtze River estuary and its adjacent waters, as well as the sediments' compositions and physicochemical properties. The process could be described well by a two-compartment first order equation. The sorbed phosphorus mainly consisted of Ex-P and Fe-P, with Ex-P being the dominant. The equilibrium isotherms could be fitted well with a modified Langmuir equation. The calculations of the thermodynamic parameters indicated that the process was spontaneous and exothermic. The CEC and the fractions of clay, calcite and organic matter were correlated with the sorption parameters, while the surface proton charge of the sediments was significantly negatively correlated with them. Considering the kinetics and phosphorus forms changes during the process, the sorption in our study could be considered that the physical process plays an important role. - Highlights: • The kinetic curves and phosphorus fractions changes during sorption were studied. • The sorbed phosphorus mainly consisted of Ex − P and Fe-P, with Ex − P being dominant. • The equilibrium isotherms and thermodynamic parameters were investigated. • Sediment composition and surface characteristics influenced phosphorus sorption parameters.

  11. Variations in early life history traits of Japanese anchovy Engraulis japonicus in the Yangtze River Estuary.

    Science.gov (United States)

    Liu, Chunlong; Xian, Weiwei; Liu, Shude; Chen, Yifeng

    2018-01-01

    Resources of Japanese anchovy ( Engraulis japonicus Temminck & Schlegel, 1846) are undergoing dramatic recessions in China as the consequence of intensifying anthropogenic activities. Elucidating the influences of local-scale environmental factors on early life history traits is of great importance to design strategies conserving and restoring the declining anchovy resources. In this research, we studied hatching date and early growth of anchovy in the Yangtze River Estuary (YRE) using information obtained from otolith microstructure. Onset of hatching season and growth rates of anchovy was compared to populations in Japan and Taiwan. In YRE, the hatching date of anchovy ranged from February 26th to April 6th and mean growth rate ranged from 0.27 to 0.77 mm/d. Anchovies hatching later had higher growth rates than individuals hatching earlier before the 25th day. Among populations, hatching onsets of anchovy from the higher latitude were later than populations in the lower latitude, and growth rates of anchovy in YRE were much lower than populations in Japan and Taiwan. Variations in hatching onsets and early growth patterns of anchovy thus provide important knowledge on understanding the adaptation of anchovy in YRE and designing management strategies on conserving China's anchovy resources.

  12. Lower Columbia River and Estuary Ecosystem Restoration Program Reference Site Study: 2011 Restoration Analysis - FINAL REPORT

    Energy Technology Data Exchange (ETDEWEB)

    Borde, Amy B.; Cullinan, Valerie I.; Diefenderfer, Heida L.; Thom, Ronald M.; Kaufmann, Ronald M.; Zimmerman, Shon A.; Sagar, Jina; Buenau, Kate E.; Corbett, C.

    2012-05-31

    The Reference Site (RS) study is part of the research, monitoring, and evaluation (RME) effort developed by the Action Agencies (Bonneville Power Administration [BPA], U.S. Army Corps of Engineers, Portland District [USACE], and U.S. Bureau of Reclamation) in response to Federal Columbia River Power System (FCRPS) Biological Opinions (BiOp). While the RS study was initiated in 2007, data have been collected at relatively undisturbed reference wetland sites in the LCRE by PNNL and collaborators since 2005. These data on habitat structural metrics were previously summarized to provide baseline characterization of 51 wetlands throughout the estuarine and tidal freshwater portions of the 235-km LCRE; however, further analysis of these data has been limited. Therefore, in 2011, we conducted additional analyses of existing field data previously collected for the Columbia Estuary Ecosystem Restoration Program (CEERP) - including data collected by PNNL and others - to help inform the multi-agency restoration planning and ecosystem management work underway in the LCRE.

  13. Identification and apportionment of hazardous elements in the sediments in the Yangtze River estuary.

    Science.gov (United States)

    Wang, Jiawei; Liu, Ruimin; Wang, Haotian; Yu, Wenwen; Xu, Fei; Shen, Zhenyao

    2015-12-01

    In this study, positive matrix factorization (PMF) and principal components analysis (PCA) were combined to identify and apportion pollution-based sources of hazardous elements in the surface sediments in the Yangtze River estuary (YRE). Source identification analysis indicated that PC1, including Al, Fe, Mn, Cr, Ni, As, Cu, and Zn, can be defined as a sewage component; PC2, including Pb and Sb, can be considered as an atmospheric deposition component; and PC3, containing Cd and Hg, can be considered as an agricultural nonpoint component. To better identify the sources and quantitatively apportion the concentrations to their sources, eight sources were identified with PMF: agricultural/industrial sewage mixed (18.6 %), mining wastewater (15.9 %), agricultural fertilizer (14.5 %), atmospheric deposition (12.8 %), agricultural nonpoint (10.6 %), industrial wastewater (9.8 %), marine activity (9.0 %), and nickel plating industry (8.8 %). Overall, the hazardous element content seems to be more connected to anthropogenic activity instead of natural sources. The PCA results laid the foundation for the PMF analysis by providing a general classification of sources. PMF resolves more factors with a higher explained variance than PCA; PMF provided both the internal analysis and the quantitative analysis. The combination of the two methods can provide more reasonable and reliable results.

  14. Numerical Study on Effects of Coastline Change on Salinity variation in the Liao River Estuary

    Science.gov (United States)

    Li, Xin; Zhang, Xue-qing; Zhao, Yang; Li, Qing-zhen; Yu, Jin-zhen

    2017-08-01

    A 3D numerical model is used to simulate the effect of coastline change on salinity distribution variation in the Liao River Estuary (LHE), China, consists of shallow channel and extensive tidal flat. Simulations are run with reclamation and land-ocean interaction to evaluate their effects on salinity transport for LHE. It is so evident to express the salinity diurnal varying with tide rather than the amount of runoff discharge; the LHE is always the rising tide advantage free of reclamation. To succinctly quantify the asymmetry degree of salinity distribution across the Gaizhou beach (GZB), the calculated parameter of low-salinity area is chosen. For dry seasons, such as May, the amplitude of its scale is from 209.54 km2 reducing to 185.6 km2. More interestingly, it demonstrates the variation shape divided into increasing at the west of GZB and decreasing in the east, varying from 7.4 to 20.9 km2, especially the east of GZB. Despite the trend is basically consistent with flood seasons, the scale is 1.6 times higher than dry seasons. Reclamation has impact on low-salinity area variation enhanced coastal change influences on salinity distribution are less distinctive, but significant in ecological sustainability just like fishery breeding stability.

  15. Methane and nitrous oxide fluxes in the polluted Adyar River and estuary, SE India

    International Nuclear Information System (INIS)

    Nirmal Rajkumar, A.; Barnes, J.; Ramesh, R.; Purvaja, R.; Upstill-Goddard, R.C.

    2008-01-01

    We measured dissolved N 2 O, CH 4 , O 2 , NH 4 + , NO 3 - and NO 2 - on 7 transects along the polluted Adyar River-estuary, SE India and estimated N 2 O and CH 4 emissions using a gas exchange relation and a floating chamber. High NO 2 - implied some nitrification of a large anthropogenic NH 4 + pool. In the lower catchment CH 4 was maximal (6.3 ± 4.3 x 10 4 nM), exceeding the ebullition threshold, whereas strong undersaturation of N 2 O and O 2 implied intense denitrification. Emissions fluxes for the whole Adyar system ∼2.5 x 10 8 g CH 4 yr -1 and ∼2.4 x 10 6 g N 2 O yr -1 estimated with a gas exchange relation and ∼2 x 10 9 g CH 4 yr -1 derived with a floating chamber illustrate the importance of CH 4 ebullition. An equivalent CO 2 flux ∼1-10 x 10 10 g yr -1 derived using global warming potentials is equivalent to total Chennai motor vehicle CO 2 emissions in one month. Studies such as this may inform more effective waste management and future compliance with international emissions agreements

  16. Rates and probable causes of freshwater tidal marsh failure, Potomac River Estuary, Northern Virginia, USA

    Science.gov (United States)

    Litwin, Ronald J.; Smoot, Joseph P.; Pavich, Milan J.; Markewich, Helaine Walsh; Oberg, Erik T.; Steury, Brent W.; Helwig, Ben; Santucci, Vincent L.; Sanders, Geoffrey

    2013-01-01

    Dyke Marsh, a distal tidal marsh along the Potomac River estuary, is diminishing rapidly in areal extent. This study documents Dyke Marsh erosion rates from the early-1860s to the present during pre-mining, mining, and post-mining phases. From the late-1930s to the mid-1970s, Dyke Marsh and the adjacent shallow riverbottom were mined for gravel, resulting in a ~55 % initial loss of area. Marsh loss continued during the post-mining phase (1976–2012). Causes of post-mining loss were unknown, but were thought to include Potomac River flooding. Post-mining areal-erosion rates increased from 0.138 ha yr−1 (~0.37 ac yr−1) to 0.516 ha yr−1(~1.67 ac yr−1), and shoreline-erosion rates increased from 0.76 m yr−1 (~2.5 ft yr−1) to 2.60 m yr−1 (~8.5 ft yr−1). Results suggest the accelerating post-mining erosion reflects a process-driven feedback loop, enabled by the marsh's severely-altered geomorphic and hydrologic baseline system; the primary post-mining degradation process is wave-induced erosion from northbound cyclonic storms. Dyke Marsh erosion rates are now comparable to, or exceed, rates for proximal coastal marshes in the same region. Persistent and accelerated erosion of marshland long after cessation of mining illustrates the long-term, and potentially devastating, effects that temporally-restricted, anthropogenic destabilization can have on estuarine marsh systems.

  17. Hudson 3 essentials

    CERN Document Server

    Meinholz, Lloyd

    2013-01-01

    A practical guide, packed with illustrations, that will help you become proficient with Hudson and able to utilize it how you want.If you are a Java developer or administrator who would to like automate some of the mundane work required to build and test software and improve software quality, this is the book for you. If you are a development manager or tester, you can also benefit from learning how Hudson works by gaining some insight into test results and historical trends.

  18. [Changes of wetland landscape pattern in Dayang River Estuary based on high-resolution remote sensing image].

    Science.gov (United States)

    Wu, Tao; Zhao, Dong-zhi; Zhang, Feng-shou; Wei, Bao-quan

    2011-07-01

    Based on the comprehensive consideration of the high resolution characteristics of remote sensing data and the current situation of land cover and land use in Dayang River Estuary wetland, a classification system with different resolutions of wetland landscape in the Estuary was established. The landscape pattern indices and landscape transition matrix were calculated by using the high resolution remote sensing data, and the dynamic changes of the landscape pattern from 1984 to 2008 were analyzed. In the study period, the wetland landscape components changed drastically. Wetland landscape transferred from natural wetland into artificial wetland, and wetland core regional area decreased. Natural wetland's largest patch area index descended, and the fragmentation degree ascended; while artificial wetland area expanded, its patch number decreased, polymerization degree increased, and the maximum patch area index had an obvious increasing trend. Increasing human activities, embankment construction, and reclamation for aquaculture were the main causes for the decrease of wetland area and the degradation of the ecological functions of Dayang River Estuary. To constitute long-term scientific and reasonable development plan, establish wetland nature reserves, protect riverway, draft strict inspective regimes for aquaculture reclamation, and energetically develop resource-based tourism industry would be the main strategies for the protection of the estuarine wetland.

  19. Over one hundred years of trace metal fluxes in the sediments of the Pearl River Estuary, South China

    International Nuclear Information System (INIS)

    Ip, C.C.M.; Li, X.D.; Zhang, G.; Farmer, J.G.; Wai, O.W.H.; Li, Y.S.

    2004-01-01

    The rapid economic development in the Pearl River Delta (PRD) region in South China in the last three decades has had a significant impact on the local environment. Estuarine sediment is a major sink for contaminants and nutrients in the surrounding ecosystem. The accumulation of trace metals in sediments may cause serious environmental problems in the aquatic system. Thirty sediment cores were collected in the Pearl River Estuary (PRE) in 2000 for a study on trace metal pollution in this region. Heavy metal concentrations and Pb isotopic compositions in the four 210 Pb-dated sediment cores were determined to assess the fluxes in metal deposits over the last one hundred years. The concentrations of Cu, Pb and Zn in the surface sediment layers were generally elevated when compared with the sub-surface layers. There has been a significant increase in inputs of Cu, Pb and Zn in the PRE since the 1970s. The results also showed that different sampling locations in the estuary received slightly different types of inputs. Pb isotopic composition data indicated that the increased Pb in the recent sediments was of anthropogenic origin. The results of trace metal influxes showed that about 30% of total Pb and 15% of total Zn in the sediments in the 1990s were from anthropogenic sources. The combination of trace metal analysis, Pb isotopic composition and 210 Pb dating in an estuary can provide vital information on the long-term accumulation of metals in sediments

  20. [Distribution and source of particulate organic carbon and particulate nitrogen in the Yangtze River Estuary in summer 2012].

    Science.gov (United States)

    Xing, Jian-Wei; Xian, Wei-Wei; Sheng, Xiu-Zhen

    2014-07-01

    Based on the data from the cruise carried out in August 2012 in the Yangtze River Estuary and its adjacent waters, spatial distributions of particulate organic carbon (POC), particulate nitrogen (PN) and their relationships with environmental factors were studied, and the source of POC and the contribution of phytoplankton to POC were analyzed combined with n (C)/n (N) ratio and chlorophyll a (Chl a) in the Yangtze River Estuary in summer 2012. The results showed that the concentrations of POC in the Yangtze River Estuary ranged from 0.68 mg x L(-1) to 34.80 mg x L(-1) in summer and the average content was 3.74 mg x L(-1), and PN contents varied between 0.03 mg x L(-1) and 9.13 mg x L(-1) with an average value of 0.57 mg x L(-1). Both of them presented that the concentrations in bottom layers were higher than those in the surface. POC and PN as well as total suspended matter (TSM) showed a extremel similar horizontal distribution trend that the highest values appeared in the near of the mouth and southwest of the survey waters, and decreased rapidly as toward the open seas, both of them showed higher contents in coastal zones and lower in outer sea. There was a fairly good positive linear relationship between POC and PN, which indicated that they had the same source. POC and PN expressed significantly positive correlations with TSM and chemical oxygen demand (COD), but showed relatively weak correlations with salinit and chlorophyll a, which demonstrated that terrestrial inputs had a strong influence on the distribution of POC and PN, and phytoplankton production was not the major source of organic matters in the Yangtze River Estuary. Both the n (C)/n (N) ratio and POC/Chl a analysis showed that the main source of POC was terrestrial inputs, and organic debris was the main existence form of POC. Quantitative analysis showed the biomass of phytoplankton only made an average of 2.54% contribution to POC in the Yangtze Rive Estuary in summer and non-living POC

  1. [Residues and potential ecological risk assessment of metal in sediments from lower reaches and estuary of Pearl River].

    Science.gov (United States)

    Xie, Wen-Ping; Wang, Shao-Bing; Zhu, Xin-Ping; Chen, Kun-Ci; Pan, De-Bo; Hong, Xiao-You; Yin, Yi

    2012-06-01

    In order to investigate the heavy metal concentrations and their potential ecological risks in surface sediments of lower reaches and estuary of Pearl River, 21 bottom sediment samples were collected from lower reaches and estuary of Pearl River. Total contents of Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Sb, Pb and Hg in these samples were measured by the inductively coupled plasma mass spectrometry (ICP-MS) and the atomic fluorescence spectrometry (AFS) and using the index of geoaccumulation and the potential ecological risk index to evaluate the pollution degree of heavy metals in the sediments. Results indicated that the concentration of total Fe and total Mn were 41658.73 and 1104.73 mg x kg(-1) respectively and toxic trace metals, such as Cr, Co, Ni, Cu, Zn, As, Se, Cd, Sb, Pb and Hg were 86.62, 18.18, 54.10, 80.20, 543.60, 119.55, 4.28, 10.60, 20.26, 104.58 and 0.520 mg x kg(-1). The descending order of pollution degree of various metals is: Cd > As approximately Zn > Hg > Pb approximately Cu approximately Cr, while the single potential ecological risk followed the order: Cd > Hg > As > Cu > Pb > Zn > Cr. The pollution extent and potential ecological risk of Cd were the most serious among all heavy metals. The distribution pattern of Cd individual potential ecological risk indices is exactly the same as that of general potential ecological risk indices for all heavy metals. Clustering analysis indicates that the sampling stations may be classified into five groups which basically reflected the characteristics of the heavy metal contamination and sedimentation environments along the different river reaches in lower reaches and estuary of Pearl Rive. In general, the serious heavy metal pollution and the high potential ecological risk existed in three river reaches: Chengcun-Shawan, Chengcun-Shundegang and Waihai-Hutiaomen. The pollution degree and potential ecological risk are higher in related river reaches of Beijiang than that in other lower reaches and

  2. Uranium isotopes in rivers, estuaries and adjacent coastal sediments of western India: their weathering, transport and oceanic budget

    International Nuclear Information System (INIS)

    Borole, D.V.; Krishnaswami, S.; Somayajulu, B.L.K.

    1982-01-01

    The two major river systems on the west coast of India, Narbada and Tapti, their estuaries and the coastal Arabian sea sediments have been extensively studied for their uranium concentrations and 234 U/ 238 U activity ratios. The 238 U concentrations in the aqueous phase of these river systems exhibit a strong positive correlation with the sum of the major cations, and with the HCO 3 - ion contents. The abundance ratio of dissolved U to the sum of the major cations in these waters is similar to their ratio in typical crustal rocks. In the estuaries, both 238 U and its great-grand daughter 234 U behave conservatively beyond chlorosities 0.14 g/l. A review of the uranium isotope measurements in river waters yield a discharge weighted-average 238 U concentration of 0.22 μg/l with a 234 U/ 238 U activity ratio of 1.20 +-0.06. The residence time of uranium isotopes in the oceans estimated from the 238 U concentration and the 234 U/ 238 U A.R. of the rivers yield conflicting results; the material balance of uranium isotopes in the marine environment still remains a paradox. If the disparity between the results is real, then an additional 234 U flux of about 0.25 dpm/cm 2 .10 3 yr into the oceans is necessitated. (author)

  3. Phytosociology of planted and natural mangrove forests in the estuary of the Ostras River, Rio de Janeiro State, Brazil

    Directory of Open Access Journals (Sweden)

    Elaine Bernini

    2014-03-01

    Full Text Available The phytosociology of planted and natural mangrove forests were compared in the estuary of the Ostras River, Rio de Janeiro State, Brazil. Vegetation sampling was performed by the plot method, and the diameter at breast height (DBH and height of individuals > 1 m tall were recorded. The results indicated that the planted forest had lower average DBH and basal area and higher density of trunks in relation to natural forest. The distribution of individuals by height class and the distribution of stems per diameter class showed that the planted forest was younger. Laguncularia racemosa and Rhizophora mangle occurred in both forests, while Avicennia schaueriana was found only in the planted forest. Laguncularia racemosa showed greater dominance and relative density at all sites analyzed, probably because it is characteristic of sites with less marine influence and the fact that the estuary had been altered by human disturbance.

  4. Natural 222Rn and 220Rn indicate the impact of the Water–Sediment Regulation Scheme (WSRS) on submarine groundwater discharge in the Yellow River estuary, China

    International Nuclear Information System (INIS)

    Xu, Bochao; Xia, Dong; Burnett, William C.; Dimova, Natasha T.; Wang, Houjie; Zhang, Longjun; Gao, Maosheng; Jiang, Xueyan; Yu, Zhigang

    2014-01-01

    Highlights: • 220 Rn and 222 Rn were combined to locate intensive SGD sites. • Influence of WSRS to SGD was found for the first time. • SGD was a dominant nutrient pathway in the Yellow River estuary. - Abstract: Submarine groundwater discharge (SGD) in estuaries brings important influences to coastal ecosystems. In this study, we observed significant SGD in the Yellow River estuary, including a fresh component, during the Water–Sediment Regulation Scheme (WSRS) period. We used the 222 Rn and 220 Rn isotope pair to locate sites of significant SGD within the study area. Three apparent SGD locations were found during a non-WSRS period, one of which became much more pronounced, according to the remarkably elevated radon levels, during the WSRS. Increased river discharge (from 245 m 3 s −1 to 3560 m 3 s −1 ) and the elevated river water level (from 11 m to 13 m) during the WSRS led to a higher hydraulic head, enhancing groundwater discharge in the estuary. Our results suggest that high river discharge (>3000 m 3 s −1 ) might be necessary for elevated fresh submarine groundwater discharging (FSGD). Vertical profiles of salinity, DO and turbidity anomalies along the benthic boundary layer also indicated significant FSGD in the estuary during the WSRS. Nutrient concentrations had positive correlations with 222 Rn during a 24-h observation, which indicates that SGD is a dominant nutrient pathway in this area

  5. Historical trends of hypoxia in Changjiang River estuary: Applications of chemical biomarkers and microfossils

    Science.gov (United States)

    Li, X.; Bianchi, T.S.; Yang, Z.; Osterman, L.E.; Allison, M.A.; DiMarco, Steven F.; Yang, G.

    2011-01-01

    Over the past two decades China has become the largest global consumer of fertilizers, which has enhanced river nutrient fluxes and caused eutrophication and hypoxia in the Yangtze (Changjiang) large river delta-front estuary (LDE). In this study, we utilized plant pigments, lignin-phenols, stable isotopes (δ13C and δ15N) and foraminiferal microfossils in 210Pb dated cores to examine the history of hypoxia in the Changjiang LDE. Two sediment cores were collected onboard R/V Dong Fang Hong 2 using a stainless-steel box-corer; one at a water depth of 24.7 m on Jun. 15, 2006 and the other at 52 m on Nov. 20, 2007, both in the hypoxic region off the Changjiang LDE. There has been a significant increase in the abundance of plant pigments after 1979 that are indicators of enhanced diatom and cyanobacterial abundance, which agrees with post-1980 record of increasing nutrient loads in the Changjiang River. The increased inputs of terrestrially derived materials to the LDE are largely woody plant sources and most likely due to deforestation that began in the early 1950s. However, post-1960 lignin data did not reflect enhanced loading of woody materials despite continued deforestation possibly due to increased trapping from greater dam construction, a reduction of deforestation in the drainage basin since the last 1990s, and soil conservation practices. The lack of linkages between bulk indices (stable isotopes, % OC, molar C/N ratios) and microfossil/chemical biomarkers may reflect relative differences in the amount of carbon tracked by these different proxies. Although NO3− is likely responsible for most of the changes in phytoplankton production (post 1970s), historical changes in N loading from the watershed and hypoxia on the LDE shelf may not be as well linked in East China Sea (ECS) sediments due to possible denitrification/ammonification processes; finally, increases in low-oxygen tolerant foraminiferal microfossils indicate there has been an increase in the

  6. Anthropogenic effects on greenhouse gas (CH4 and N2O) emissions in the Guadalete River Estuary (SW Spain)

    International Nuclear Information System (INIS)

    Burgos, M.; Sierra, A.; Ortega, T.; Forja, J.M.

    2015-01-01

    Coastal areas are subject to a great anthropogenic pressure because more than half of the world's population lives in its vicinity causing organic matter inputs, which intensifies greenhouse gas emissions into the atmosphere. Dissolved concentrations of CH 4 and N 2 O have been measured seasonally during 2013 in the Guadalete River Estuary, which flows into the Cadiz Bay (southwestern Spanish coast). It has been intensely contaminated since 1970. Currently it receives wastewater effluents from cities and direct discharges from nearby agriculture crop. Eight sampling stations have been established along 18 km of the estuary. CH 4 and N 2 O were measured using a gas chromatograph connected to an equilibration system. Additional parameters such as organic matter, dissolved oxygen, nutrients and chlorophyll were determinate as well, in order to understand the relationship between physicochemical and biological processes. Gas concentrations increased from the River mouth toward the inner part, closer to the wastewater treatment plant discharge. Values varied widely within 21.8 and 3483.4 nM for CH 4 and between 9.7 and 147.6 nM for N 2 O. Greenhouse gas seasonal variations were large influenced by the precipitation regime, masking the temperature influence. The Guadatete Estuary acted as a greenhouse gas source along the year, with mean fluxes of 495.7 μmol m −2 d −1 and 92.8 μmol m −2 d −1 for CH 4 and N 2 O, respectively. - Highlights: • The estuary acts as a source of atmospheric methane and nitrous oxide. • Anthropogenic inputs affect the distribution of the greenhouse gases. • Dissolved gases presented an important longitudinal gradient. • Seasonal variations highly depended on the precipitation regimen

  7. Waterbird Population Changes in the Wetlands at Chongming Dongtan in the Yangtze River Estuary, China

    Science.gov (United States)

    Ma, Zhijun; Wang, Yong; Gan, Xiaojing; Li, Bo; Cai, Yinting; Chen, Jiakuan

    2009-06-01

    We studied the changes in wetland habitats and waterbird communities between the 1980s and the 2000s at Chongming Dongtan, a Ramsar site in the Yangtze River estuary, an ecologically important region. This region is an important stopover site for shorebirds along the East Asian-Australasian flyway and is extensively used by waterfowl. A net loss of 11% of the wetland area was estimated during study periods at Chongming Dongtan. The change was dependent on wetland types: while the area of artificial habitats such as paddy fields and aquacultural ponds more than doubled, more than 65% of natural habitats including sea bulrush ( Scirpus mariqueter) and common reed ( Phragmites australis) marshes were lost over the two decades. An exotic plant species introduced from North America, smooth cordgrass ( Spartina alterniflora), occupied 30% of the vegetated intertidal zone by the 2000s. Although waterbird species richness did not change between the 1980s (110) and the 2000s (111), 13 species found in 1980s were replaced by 14 newly recorded species. Moreover, there were more species with declining trends (58) than with increasing trends (19). The population trends of species were affected by residential status and habitat types. Transients, wintering migrants, and habitat specialists were more likely to show declining trends compared to those breeding at Dongtan (including year-round and summer residents) and habitat generalists. Furthermore, species associated mainly with natural wetlands were more likely to decline than those associated mainly with artificial wetlands. These patterns suggest that the loss and change of wetland habitats at Chongming Dongtan adversely affected local population dynamics and might have contributed to the global decline of some waterbird species. Because Chongming Dongtan provides stopover and wintering habitats for many migratory waterbirds, protection and restoration of natural wetlands at Chongming Dongtan are urgently needed.

  8. [Faunal characteristics and distribution pattern of crustaceans in the vicinity of Pearl River estuary].

    Science.gov (United States)

    Huang, Zi-Rong; Sun, Dian-Rong; Chen, Zuo-Zhi; Zhang, Han-Hua; Wang, Xue-Hui; Wang, Yue-Zhong; Fang, Hong-Da; Dong, Yan-Hong

    2009-10-01

    Based on the data of bottom trawl surveys in the vicinity of Pearl River estuary in August (summer), October (autumn), December (winter) 2006, and April (spring) 2007, the faunal characteristics and distribution pattern of crustaceans were analyzed. A total of 54 species belonging to 25 genera, 17 families, and 2 orders were collected, including 22 species of shrimps, 22 species of crabs, and 10 species of squills. Most of the crustaceans were tropical-subtropical warm-water species, a few of them were eurythermal species, and no warm-water and cold-water species occurred. Euryhaline species were most abundant, followed by halophile species, and the low-salinity species were the least. Most of the crustacean species belonged to the fauna of Indian Ocean-western Pacific Ocean. The faunal assemblages were closer to those of the East China Sea, Philippine Sea, Indonesia Sea, and the Japan Sea, and estranger with those of the Yellow Sea, Bohai Sea, and Korea Sea. The dominant species were Metapenaeus joyner, Oratosquilla oratoria, Charybdis miles, Portunus sanguinolentus, Harpiosquilla harpax, Charybdis feriatus, Charybdis japonica, Oratosquilla nepa, Solenocera crassicornis, Portunus trituberculatus, and Calappa philargius. The crustaceans had the largest species number (33) in autumn and the least one (26) in spring, and the highest stock density at the water depth of crabs had the highest stock density (41.81 kg x km(-2)), followed by shrimps (38.91 kg x km(-2)), and squills (18.88 kg x km(-2)). The stock densities of the 3 species groups showed an obvious seasonal variation. Shrimps had the highest stock density (120.32 kg x km(-2)) in summer and the lowest density (0.67 kg x km(-2)) in spring, while crabs and squills had the highest density (62.01 and 29.49 kg x km(-2), respectively) in winter and the lowest density (24.64 and 6.30 kg x km(-2), respectively) in autumn.

  9. Osprey: worldwide sentinel species for assessing and monitoring environmental contamination in rivers, lakes, reservoirs, and estuaries.

    Science.gov (United States)

    Grove, Robert A; Henny, Charles J; Kaiser, James L

    2009-01-01

    In the United States, many fish and wildlife species have been used nationwide to monitor environmental contaminant exposure and effects, including carcasses of the bald eagle (Haliaeetus leucocephalus), the only top avian predator regularly used in the past. Unfortunately, bald eagles are sensitive to investigator intrusion at the nest. Thus, the osprey (Pandion haliaetus) is evaluated as a potential sentinel species for aquatic ecosystems. Several characteristics support the choice of the osprey as a sentinel species, including: (1) fish-eating diet atop the aquatic food web, (2) long-lived with strong nest fidelity, (3) adapts to human landscapes (potentially the most contaminated), (4) tolerates short-term nest disturbance, (5) nests spatially distributed at regular intervals, (6) highly visible nests easily located for study, (7) ability to accumulate most, if not all, lipophilic contaminants, (8) known sensitivity to many contaminants, and (9) nearly a worldwide distribution. These osprey traits have been instrumental in successfully using the species to understand population distribution, abundance, and changes over time; the effects of various contaminants on reproductive success; how contaminants in prey (fish on biomass basis) contribute to egg concentrations (i.e., biomagnification factors); and spatial residue patterns. Data summarized include nesting population surveys, detailed nesting studies, and chemical analyses of osprey egg, organ, blood, and feather samples for contaminants that bioaccumulate and/or biomagnify in aquatic food webs; and biochemical evaluations of blood and various organs. Studies in the United States, Canada, Mexico, Europe, and elsewhere have shown the osprey to be a useful sentinel species for monitoring selected environmental contaminants, including some emerging contaminants in lakes, reservoirs, rivers, and estuaries.

  10. Heavy metal and Pb isotopic compositions of aquatic organisms in the Pearl River Estuary, South China

    International Nuclear Information System (INIS)

    Ip, C.C.M.; Li, X.D.; Zhang, G.; Wong, C.S.C.; Zhang, W.L.

    2005-01-01

    The accumulation of trace metals in aquatic organisms may lead to serious health problems through the food chain. The present research project aims to study the accumulation and potential sources of trace metals in aquatic organisms of the Pearl River Estuary (PRE). Four groups of aquatic organisms, including fish, crab, shrimp, and shellfish, were collected in the PRE for trace metal and Pb isotopic analyses. The trace metal concentrations in the aquatic organism samples ranged from 0.01 to 2.10 mg/kg Cd, 0.02 to 4.33 mg/kg Co, 0.08 to 4.27 mg/kg Cr, 0.15 to 77.8 mg/kg Cu, 0.17 to 31.0 mg/kg Ni, 0.04 to 30.7 mg/kg Pb, and 8.78 to 86.3 mg/kg Zn (wet weight). High concentrations of Cd were found in crab, shrimp and shellfish samples, while high concentration of Pb was found in fish. In comparison with the baseline reference values in other parts of the world, fish in the PRE had the highest elevated trace metals. The results of Pb isotopic compositions indicated that the bioaccumulation of Pb in fish come from a wide variety of food sources and/or exposure pathways, particularly the anthropogenic inputs. - Relative high concentrations of Cd were found in crab, shrimp and shellfish samples while high concentration of Pb was found in fish, particularly from the anthropogenic inputs

  11. [Photodegradation of chromophoric dissolved organic matter from Jiulong River Estuary under natural solar radiation].

    Science.gov (United States)

    Guo, Wei-dong; Cheng, Yuan-yue

    2008-06-01

    Low salinity water sample collected from Jiulong River Estuary filtered using 0.2 microm Millipore filter was exposed to natural solar radiation from 10:00 to 16:00 each day during one week period in early and late May, 2005. Photodegradation of fluorescence and absorption properties of CDOM (chromophoric dissolved organic matter) was observed. The results showed that humic-like fluorescence (lambda Ex/lambda Em = 350/450 nm), tryptophan-like fluorescence (lambda Ex/lambda Em = 225/350 nm) and absorption coefficient of CDOM can be significantly photodegraded during short-term solar exposure in early summer. These photodegradation processes followed the first-order dynamic equation. The degradation half time of humic-like fluorescence, tryptophan-like fluorescence and a (280) were calculated as 3.5-5.1 d, 3.0-4.5 d and 6.3 d. The absorption loss spectra of CDOM indicated that the solar UV radiation was responsible for the photochemical degradation of CDOM. The loss of humic-like fluorescence (70%) was obviously higher than loss of a (280) (about 40%), suggesting that photobleaching ability of CDOM fluorophores were much stronger than CDOM chromophores. However, the correlation relationship between humic-like fluorescence and absorption coefficient are still kept. A250/A350 of CDOM increased till the end of radiation experiment compared with the control group, suggesting photodegradation may decrease the average molecular size of CDOM. These findings show that terrestrial CDOM can be transformed and removed by photochemical decomposition after transport into the sea, and photodegradation might be an important sink for terrestrial CDOM.

  12. Occurrence and levels of polybrominated diphenyl ethers in surface sediments from the Yellow River Estuary, China.

    Science.gov (United States)

    Yuan, Zijiao; Liu, Guijian; Lam, Michael Hon Wah; Liu, Houqi; Da, Chunnian

    2016-05-01

    A total of 21 surface sediments collected from the Yellow River Estuary, China were analyzed for 40 kinds of polybrominated diphenyl ethers (PBDEs) using gas chromatography-mass spectrometry (GC-MS). Their levels, spatial distribution, congener profiles and possible sources were investigated. Only ten congeners were detected in the sediments. The total concentrations of the lower brominated BDEs (∑PBDEslow, PBDEs excluding BDE 209) and BDE 209 ranged from 0.482 ng/g to 1.07 ng/g and 1.16-5.40 ng/g, with an average value of 0.690 and 2.79 ng/g, respectively, which were both at the low end of the global contamination level. The congener profiles were dominated by BDE 209, with the average value accounting for 79.2% of the total PBDEs in the sediment samples. Among the nine lower brominated BDE congeners, BDE 47, 99 and 183 had high abundances. Although the commercial Penta/Octa-BDE products have been banned in most countries, the residual commercial Penta/Octa/Deca-BDE products and the debromination of highly brominated BDE compounds such as BDE 209 were still found to be the possible sources for the trace level of PBDEs in the present study area. In spite of the gradual removal of the commercial PBDEs in the world, the present research results further suggested that scientific attention should not be reduced on the issue of environmental contamination caused by these outdated chemical compounds. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Tempo-spatial dynamics of water quality and its response to river flow in estuary of Taihu Lake based on GOCI imagery.

    Science.gov (United States)

    Du, Chenggong; Li, Yunmei; Wang, Qiao; Liu, Ge; Zheng, Zhubin; Mu, Meng; Li, Yuan

    2017-12-01

    Knowledge of tempo-spatial dynamics of water quality and its response to river flow is important for the management of lake water quality because river discharge associated with rainstorms can be an important source of pollutants to the estuary. Total phosphorus (TP), chlorophyll a (Chl-a), and total suspended matter (TSM) are important indexes of water quality and important factors influencing eutrophication and algal blooms. In this study, remote sensing was used to monitor these indexes to investigate the effects of river discharge on the estuary of Taihu Lake by the largest inflow river which is Chendong River using a total of 136 Geostationary Ocean Color Images (GOCI). In situ datasets collected during the four cruise experiments on Taihu Lake between 2011 and 2015 were used to develop the TP, Chl-a, and TSM inversion models based on simple empirical algorithms: 154 points for TP (mg/L), 114 for Chl-a (μg/L), and 181 for TSM (mg/L). The spatial and temporal changes of the concentration of the three parameters in the Chendong River estuary were analyzed by combining the GOCI data, the flow of the Chendong River, and meteorological data throughout the year in 2014. The several key findings are as follows: (1) In summer and autumn, TP, Chl-a, and TSM contents were significantly higher than in winter and spring. TP and Chl-a have a few similar distribution characteristics. And organic suspended matter in summer was the main reason for the increase of the TSM concentration. (2) The severe surface erosion in the rivers cannot be ignored; the high erodibility is an important factor in the increase of TP and TSM concentrations in the estuary. The concentration of the water quality parameter showed exponential decay with distance from the shore. The concentration decreased slowly after 12 km and then remained essentially constant. (3) TP content in the Chendong River estuary decreased under steady flow inputs and dramatically increased when the flow became large

  14. Detecting the transport barriers in the Pearl River estuary, Southern China with the aid of Lagrangian coherent structures

    Science.gov (United States)

    Wei, Xing; Zhan, Haigang; Cai, Shuqun; Zhan, Weikang; Ni, Peitong

    2018-05-01

    Knowledge of horizontal transport pathways is important for the protection of the marine ecosystem in coastal areas. In this paper, we develop a 3D model to simulate hydrodynamics and particle transport in the Pearl River Estuary (PRE), Southern China, to study the barriers to transport in the PRE. Specifically, we use the flow velocity produced by the model to locate Lagrangian coherent structures (LCSs) hidden in ocean surface currents. Our findings show that a remarkable LCS begins upstream near the Humen inlet, extends to the Wanshan Islands via Neilingding Island, and can act as a transport barrier in the estuary. This LCS appeared 1-2 h after high tide and was persistent for 6-7 h during every ebb tide. Particles released on the west side of the LCS moved downstream, exited the estuary by Daxi Channel, and seldom spread to the east side, especially the Hong Kong Sea area. An analysis of several scenarios suggested that the formation of this LCS was due to topography restrictions and tidal forces.

  15. The changes in trace metal contamination over the last decade in surface sediments of the Pearl River Estuary, South China.

    Science.gov (United States)

    Chen, Baowei; Liang, Ximei; Xu, Weihai; Huang, Xiaoping; Li, Xiangdong

    2012-11-15

    Surface sediments can provide useful information on the recent pollution status of an estuary. One recent field survey was carried out in the Pearl River Estuary (PRE), South China in 2011. The comparisons with previous surveys demonstrated that the concentrations of Ni and Pb in the PRE declined over the last decade, but the concentration of Cu increased in the same time frame. The significant decreases in the concentrations of Ni and Pb were probably due to a reduction of anthropogenic inputs, such as industrial wastewater, into the PRE environment, and the ban imposed on leaded gasoline. Statistical analyses have consistently demonstrated that the process of the sedimentation of fine particles was the dominant factor in controlling the transport and distribution of trace metals in the PRE. The riverine trace metals generally displayed a pattern of diffusion from the northwest to the southeast in the estuary. However, the riparian industrial activities at the east bank of the inner PRE caused significant metal contamination in sediments. In general, effective pollution control measures in the PRD region have decreased the levels of some trace metals in the entire PRE over the last decade with the exception of Cu. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Modeled long-term changes of DIN:DIP ratio in the Changjiang River in relation to Chl-α and DO concentrations in adjacent estuary

    Science.gov (United States)

    Wang, Jianing; Yan, Weijin; Chen, Nengwang; Li, Xinyan; Liu, Lusan

    2015-12-01

    In the past four decades (1970-2013), nitrogen and phosphorous inputs to the Changjiang River basin, mainly from human activities, have increased 3-fold and 306-fold, respectively. The riverine nutrient fluxes to the estuary have also grown exponentially. Dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorous (DIP) fluxes of the Changjiang River increased by 338% and 574% during 1970-2013 period, and red tides and benthic hypoxia have been observed in the outflow region of the Changjiang River in the East China Sea (ECS). We assumed that time series changes in the DIN:DIP ratio from the Changjiang River could have a significant impact on Chlorophyll-α (Chl-α) concentration in the surface sea water and dissolved oxygen (DO) concentration in the bottom sea water of the Changjiang estuary. Our study showed that the DIN:DIP ratio from the Changjiang River increased from 76 to 384 between 1970 and 1985, and decreased from 255 to 149 between 1986 and 2013. The observed Chl-α concentration increased by 146% from 1992 to 2010 in the Changjiang estuary, and was negatively related to the DIN:DIP ratio in 1992-2010. Bottom sea water DO concentration decreased by 24.6% during 1992-2010 and a "low oxygen zone" (122°∼123°E, 32°∼33°N) was observed during summer since 1999. The anthropogenically enhanced nutrient inputs dominated river DIN and DIP fluxes and influenced Chl-α concentrations as well as bottom DO concentrations in the estuary. Scenarios emphasizing global collaboration and proactive environmental problem-solving may result in reductions in the river nutrient exports and in Chl-α and DO concentration in the Changjiang estuary by 2050.

  17. Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2004

    Energy Technology Data Exchange (ETDEWEB)

    Diefenderfer, Heida L.; Roegner, Curtis; Thom, Ronald M.; Dawley, Earl M.; Whiting, Allan H.; Johnson, Gary E.; Sobocinski, Kathryn L.; Anderson, Michael G.; Ebberts, Blaine

    2005-12-15

    indicators for detecting a signal in the estuarine system resulting from the multiple projects were also reviewed, i.e. organic matter production, nutrient cycling, sedimentation, food webs, biodiversity, salmon habitat usage, habitat opportunity, and allometry. In subsequent work, this information will be used to calculate the over net effect on the ecosystem. To evaluate the effectiveness of habitat restoration actions in the lower Columbia River and estuary, a priority of this study has been to develop a set of minimum ecosystem monitoring protocols based on metrics important for the CRE. The metrics include a suite of physical measurements designed to evaluate changes in hydrological and topographic features, as well as biological metrics that will quantify vegetation and fish community structure. These basic measurements, intended to be conducted at all restoration sites in the CRE, will be used to (1) evaluate the effectiveness of various restoration procedures on target metrics, and (2) provide the data to determine the cumulative effects of many restoration projects on the overall system. A protocol manual is being developed for managers, professional researchers, and informed volunteers, and is intended to be a practical technical guide for the design and implementation of monitoring for the effects of restoration activities. The guidelines are intended to standardize the collection of data critical for analyzing the anticipated ecological change resulting from restoration treatments. Field studies in 2005 are planned to initiate the testing and evaluation of these monitoring metrics and protocols and initiate the evaluation of higher order metrics for cumulative effects.

  18. Collection and analysis of remotely sensed data from the Rhode River Estuary Watershed. [ecological parameters of Chesapeake Bay

    Science.gov (United States)

    Jenkins, D. W.

    1972-01-01

    NASA chose the watershed of Rhode River, a small sub-estuary of the Bay, as a representative test area for intensive studies of remote sensing, the results of which could be extrapolated to other estuarine watersheds around the Bay. A broad program of ecological research was already underway within the watershed, conducted by the Smithsonian Institution's Chesapeake Bay Center for Environmental Studies (CBCES) and cooperating universities. This research program offered a unique opportunity to explore potential applications for remote sensing techniques. This led to a joint NASA-CBCES project with two basic objectives: to evaluate remote sensing data for the interpretation of ecological parameters, and to provide essential data for ongoing research at the CBCES. A third objective, dependent upon realization of the first two, was to extrapolate photointerpretive expertise gained at the Rhode River watershed to other portions of the Chesapeake Bay.

  19. Looking for Damming Effects on the Sedimentation Rates in the Estuary Region of the Paraiba do Sul River, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Wanderley, C. V.A. [Departamento de Quimica, Pontificia Universidade Catolica, PUC-RIO, Rio de Janeiro, RJ (Brazil); Godoya, J. M. [Departamento de Quimica, Pontificia Universidade Catolica, PUC-RIO, Rio de Janeiro and Instituto de Radioprotecao e Dosimetria, IRD, Comissao Nacional de Energia Nuclear, Rio de Janeiro, RJ (Brazil); Rezende, C. E. [Centro de Biociencias e Biotecnologia, Universidade Estadual Norte Fluminense Darcy Ribeiro, UENF, Campos dos Goytacases, RJ (Brazil); Godoy, M. L.D.P.; Carvalho, Z. L. [Instituto de Radioprotecao e Dosimetria, IRD, Comissao Nacional de Energia Nuclear, Rio de Janeiro, RJ (Brazil)

    2013-07-15

    The objective of this work is to evaluate the sedimentation rates at Paraiba do Sul estuary and to correlate them with the strong erosion that occurs in Atafona, Rio de Janeiro. The coastal line of Atafona has been regressing in the last 50 years and the sea has destroyed some constructions. There are traces that one of the factors of the situation in Atafona is the disruption of the equilibrium deposition-erosion. The sedimentation rates will show the influence of the river material input and when it happened, enabling the evaluation of the human and natural impacts suffered by the river. The work was based on three transects, north, centre and south, where 10 sediment cores with about 350 sediment samples were collected in January 2010. The sedimentation rates were obtained based on {sup 210}Pb dating and the data validated based on the heavy metal profiles and the local anthropogenic impacts records. (author)

  20. A Synthesis of Environmental and Plant Community Data for Tidal Wetland Restoration Planning in the Lower Columbia River and Estuary

    Energy Technology Data Exchange (ETDEWEB)

    Diefenderfer, Heida L.; Borde, Amy B.; Cullinan, Valerie I.

    2013-12-01

    This report reanalyzes and synthesizes previously existing environmental and plant community data collected by PNNL at 55 tidal wetlands and 3 newly restored sites in the lower Columbia River and estuary (LCRE) between 2005 and 2011. Whereas data were originally collected for various research or monitoring objectives of five studies, the intent of this report is to provide only information that will have direct utility in planning tidal wetland restoration projects. Therefore, for this report, all tidal wetland data on plants and the physical environment, which were originally developed and reported by separate studies, were tabulated and reanalyzed as a whole. The geographic scope of the data collected in this report is from Bonneville Lock and Dam to the mouth of the Columbia River

  1. The Accumulation and Seasonal Dynamic of the Soil Organic Carbon in Wetland of the Yellow River Estuary, China

    Directory of Open Access Journals (Sweden)

    Xianxiang Luo

    2014-01-01

    Full Text Available The wetland of the Yellow River estuary is a typical new coastal wetland in northern China. It is essential to study the carbon pool and its variations for evaluating the carbon cycle process. The study results regarding the temporal-spatial distribution and influential factors of soil organic carbon in four typical wetlands belonging to the Yellow River estuary showed that there was no significant difference in the contents of the surface soil TOC to the same season among the four types of wetlands. For each type of wetlands, the TOC content in surface soils was significantly higher in October than that in both May and August. On the whole, the obvious differences in DOC contents in surface soils were not observed in the different wetland types and seasons. The peak of TOC appeared at 0–10 cm in the soil profiles. The contents of TOC and DOC were significantly higher in salsa than those in reed, suggesting that the rhizosphere effect of organic carbon in salsa was more obvious than that in reed. The results of the principal component analysis showed that the nitrogen content, salinity, bulk density, and water content were dominant influential factors for organic carbon accumulation and seasonal variation.

  2. Mercury profiles in sediments of the Pearl River Estuary and the surrounding coastal area of South China

    International Nuclear Information System (INIS)

    Shi Jianbo; Ip, Carman C.M.; Zhang Gan; Jiang Guibin; Li Xiangdong

    2010-01-01

    The spatial and temporal variations of mercury (Hg) in sediments of the Pearl River Estuary (PRE) and the surrounding coastal area (South China Sea) were studied. In surface sediments, the concentrations of Hg ranged from 1.5 to 201 ng/g, with an average of 54.4 ng/g, displaying a decreasing trend with the distance from the estuary to the open sea. This pattern indicates that the anthropogenic emissions from the Pearl River Delta (PRD) region are probably the main sources of Hg in this coastal region. Using the 210 Pb dating technique, the historical changes in the concentrations and influxes of Hg in the last 100 years were also investigated. The variations in Hg influxes in sediment cores obviously correlate with the economic development and urbanization that has occurred the PRD region, especially in the last three decades. - The spatial and historical changes of Hg in sediment reflect the industrial development and urbanization of the region in south China.

  3. First occurrence of thinlip grey mullet, Liza ramada (Risso, 1827 in the Odra River estuary (NW Poland: genetic identification

    Directory of Open Access Journals (Sweden)

    Remigiusz Panicz

    2016-07-01

    Full Text Available The presence of exotic fish species in the Baltic Sea and its tributaries poses a serious threat for native ichthyofauna, mainly due to the spread of new pathogens. As the accurate identification of species is essential for an effective assessment of changes related to the appearance of non-native species in an aquatic environment, in this paper we tested the usefulness of biometrics and molecular markers in identifying a specimen from the Mugilidae family found in the Odra estuary. The results demonstrated that unambiguous identification of the specimen using biometric features was impossible due to high morphological similarities shared by grey mullets. Unambiguous identification was possible only due to molecular markers, e.g. rhodopsin gene, which helped to identify the collected fish specimen as Liza ramada (Risso, 1827, the first specimen of this species found in the Odra River estuary. The presence of an L. ramada specimen in the Odra River – which could signal the expansion of non-native species into wider ranges – may be linked to climate change or human activity.

  4. Surficial and vertical distribution of heavy metals in different estuary wetlands in the Pearl river, South China

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Honggang; Cui, Baoshan [State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing (China); Zhang, Kejiang [Xinjiang Research Center of Water and Wastewater Treatment, Xinjiang Deland Co., LTD., Urumqi (China)

    2012-10-15

    A total of 87 soil profiles sampled from five types of wetlands in the Pearl River estuary were analyzed to investigate the surficial and vertical distributions of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn). The results show that wetlands directly connected with rivers (e.g., riparian wetlands, estuarine wetlands, and mangrove wetlands) has much higher metal concentrations than those indirectly connected with rivers (e.g., pond wetlands and reclaimed wetlands). The river water is the major pollution source for all investigated heavy metals. The vertical distribution of heavy metals can be classified into three patterns: (i) linear distribution pattern. The concentration of heavy metals gradually decreases with an increase in soil depth (for riparian and estuarine wetlands); (ii) irregular and stable pattern (for pond and reclaimed wetlands); and (iii) middle enrichment pattern (for mangrove wetlands). In addition to river-borne inputs, a variety of vegetation composition, hydraulic conditions, and human activities also contribute to the variation in distribution of heavy metals in different wetlands. Soil properties (e.g., particle size, pH, salinity, and SOM) also affect the distribution of trace metals in each soil layer. The major pollution source of heavy metals is industrial wastewater. Other sources include agriculture and domestic premises, and atmospheric deposition. This study provides a sound basis for the risk assessment of heavy metals in the studied wetlands and for wetland conservation in general. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Linkages between the spatial toxicity of sediments and sediment dynamics in the Yangtze River Estuary and neighboring East China Sea.

    Science.gov (United States)

    Gao, Jinjuan; Shi, Huahong; Dai, Zhijun; Mei, Xuefei; Zong, Haibo; Yang, Hongwei; Hu, Lingling; Li, Shushi

    2018-02-01

    Anthropogenic activities are driving an increase in sediment contamination in coastal areas. This poses significant challenges for the management of estuarine ecosystems and their adjacent seas worldwide. However, few studies have been conducted on how dynamic mechanisms affect the sediment toxicity in the estuarine environment. This study was designed to investigate the linkages between sediment toxicity and hydrodynamics in the Yangtze River Estuary (YRE) area. High sediment toxicity was found in the Yangtze River mouth (Region I), the depocenter of the Yangtze River Delta (Region II), and the southeastern area of the adjacent sea (Region III), while low sediment toxicity was found in the northeastern offshore region (Region IV). A spatial comparison analysis and regression model indicated that the distributed pattern of sediment toxicity was likely related to hydrodynamics and circumfluence in the East China Sea (ECS) shelf. Specifically, high sediment toxicity in Region I may be affected by the Yangtze River Pump (YRP) and the low hydrodynamics there, and high toxicity in Region II can be influenced by the low sediment dynamics and fine sediment in the depocenter. The high sediment toxicity in Region III might be related to the combination of the YRP and Taiwan Warm Current, while the low toxicity in Region IV may be influenced by the local coarse-grained relict sand with strong sediment dynamics there. The present research results further suggest that it is necessary to link hydrodynamics and the spatial behavior of sediment and sediment-derived pollutants when assessing the pollution status of estuarine environments, especially for those mega-estuaries and their neighboring ocean environments with complex waves, tides and ocean currents. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Numerical study of hydrodynamic and salinity transport processes in the Pink Beach wetlands of the Liao River estuary, China

    Directory of Open Access Journals (Sweden)

    H. Qiao

    2018-06-01

    Full Text Available Interaction studies of vegetation within flow environments are essential for the determination of bank protection, morphological characteristics and ecological conditions for wetlands. This paper uses the MIKE 21 hydrodynamic and salinity model to simulate the hydrodynamic characteristics and salinity transport processes in the Pink Beach wetlands of the Liao River estuary. The effect of wetland plants on tidal flow in wetland areas is represented by a varying Manning coefficient in the bottom friction term. Acquisition of the vegetation distribution is based on Landsat TM satellites by remote sensing techniques. Detailed comparisons between field observation and simulated results of water depth, salinity and tidal currents are presented in the vegetated domain of the Pink Beach wetlands. Satisfactory results were obtained from simulations of both flow characteristics and salinity concentration, with or without vegetation. A numerical experiment was conducted based on variations in vegetation density, and compared with the tidal currents in non-vegetated areas; the computed current speed decreased remarkably with an increase in vegetation density. The impact of vegetation on water depth and salinity was simulated, and the findings revealed that wetland vegetation has an insignificant effect on the water depth and salinity in this wetland domain. Several stations (from upstream to downstream in the Pink Beach wetlands were selected to estimate the longitudinal variation of salinity under different river runoff conditions; the results showed that salinity concentration decreases with an increase in river runoff. This study can consequently help increase the understanding of favourable salinity conditions for particular vegetation growth in the Pink Beach wetlands of the Liao River estuary. The results also provide crucial guidance for related interaction studies of vegetation, flow and salinity in other wetland systems.

  7. Occurrence and levels of polybrominated diphenyl ethers in surface sediments from the Yellow River Estuary, China

    International Nuclear Information System (INIS)

    Yuan, Zijiao; Liu, Guijian; Lam, Michael Hon Wah; Liu, Houqi; Da, Chunnian

    2016-01-01

    A total of 21 surface sediments collected from the Yellow River Estuary, China were analyzed for 40 kinds of polybrominated diphenyl ethers (PBDEs) using gas chromatography-mass spectrometry (GC–MS). Their levels, spatial distribution, congener profiles and possible sources were investigated. Only ten congeners were detected in the sediments. The total concentrations of the lower brominated BDEs (∑PBDEs_l_o_w_, PBDEs excluding BDE 209) and BDE 209 ranged from 0.482 ng/g to 1.07 ng/g and 1.16–5.40 ng/g, with an average value of 0.690 and 2.79 ng/g, respectively, which were both at the low end of the global contamination level. The congener profiles were dominated by BDE 209, with the average value accounting for 79.2% of the total PBDEs in the sediment samples. Among the nine lower brominated BDE congeners, BDE 47, 99 and 183 had high abundances. Although the commercial Penta/Octa-BDE products have been banned in most countries, the residual commercial Penta/Octa/Deca-BDE products and the debromination of highly brominated BDE compounds such as BDE 209 were still found to be the possible sources for the trace level of PBDEs in the present study area. In spite of the gradual removal of the commercial PBDEs in the world, the present research results further suggested that scientific attention should not be reduced on the issue of environmental contamination caused by these outdated chemical compounds. - Highlights: • This is the first study concentrating specifically on PBDEs in the study area. • The commercial Penta/Octa/Deca-BDE products were the possible sources. • The debromination of highly brominated PBDEs were also found to be the sources. • Scientific attention should not be reduced on these outdated chemical compounds. - The commercial Penta/Octa/Deca-BDE products and the debromination of highly brominated BDE compounds were found to be the possible sources.

  8. Diversity of fish sound types in the Pearl River Estuary, China

    Directory of Open Access Journals (Sweden)

    Zhi-Tao Wang

    2017-10-01

    Full Text Available Background Repetitive species-specific sound enables the identification of the presence and behavior of soniferous species by acoustic means. Passive acoustic monitoring has been widely applied to monitor the spatial and temporal occurrence and behavior of calling species. Methods Underwater biological sounds in the Pearl River Estuary, China, were collected using passive acoustic monitoring, with special attention paid to fish sounds. A total of 1,408 suspected fish calls comprising 18,942 pulses were qualitatively analyzed using a customized acoustic analysis routine. Results We identified a diversity of 66 types of fish sounds. In addition to single pulse, the sounds tended to have a pulse train structure. The pulses were characterized by an approximate 8 ms duration, with a peak frequency from 500 to 2,600 Hz and a majority of the energy below 4,000 Hz. The median inter-pulsepeak interval (IPPI of most call types was 9 or 10 ms. Most call types with median IPPIs of 9 ms and 10 ms were observed at times that were exclusive from each other, suggesting that they might be produced by different species. According to the literature, the two section signal types of 1 + 1 and 1 + N10 might belong to big-snout croaker (Johnius macrorhynus, and 1 + N19 might be produced by Belanger’s croaker (J. belangerii. Discussion Categorization of the baseline ambient biological sound is an important first step in mapping the spatial and temporal patterns of soniferous fishes. The next step is the identification of the species producing each sound. The distribution pattern of soniferous fishes will be helpful for the protection and management of local fishery resources and in marine environmental impact assessment. Since the local vulnerable Indo-Pacific humpback dolphin (Sousa chinensis mainly preys on soniferous fishes, the fine-scale distribution pattern of soniferous fishes can aid in the conservation of this species. Additionally, prey and predator

  9. Employment of the generalized adsorption model for the prediction of the solid-water distribution of radiocesium in the river-estuary-ocean system

    International Nuclear Information System (INIS)

    Fan, Qiaohui; Takahashi, Yoshio

    2017-01-01

    Since last century, a large amount of radiocesium (RCs) released from atomic weapon tests and nuclear accidents, such as in Chernobyl and Fukushima, was directly introduced into the environment through atmospheric transportation and deposition on land surface soil, discharged into river systems by erosion effects during rainfall, and finally released into the ocean. In this study, a generalized adsorption model (GAM) for Cs + was employed to estimate the solid-water distribution of Cs + in the river-estuary-ocean system. The results confirmed that the capacity of each adsorption site of river sediments, i.e., interlayer site, type II site, and planar site, can be precisely optimized through the adsorption isotherm of Cs + on the river sediments combined with the radiocesium interception potential (RIP) and cation exchange capacity (CEC). According to the GAM, the main contributor for Cs + adsorption is the frayed edge site rather than others due to the very low concentration of Cs + in the river-estuary-ocean system. The different solid-water distribution of Cs + in the river-estuary-ocean system was dominantly controlled by the salinity in the aqueous phase. Therefore, Cs + should be highly reactive with strong adsorptive character to particulate matter in the river system, whereas a conservative distribution must be dominant in ocean with much weaker affinity to particulate matter because of the high salinity. - Highlights: • A new method to extend the utility range of GAM from illite to natural samples. • GAM was adapted to quantitatively explore the transportation of radiocesium in river in rive-estuary-ocean system. • High reactivity in river water and conservative behavior in seawater were clarified.

  10. Aquatic environmental DNA detects seasonal fish abundance and habitat preference in an urban estuary.

    Directory of Open Access Journals (Sweden)

    Mark Y Stoeckle

    Full Text Available The difficulty of censusing marine animal populations hampers effective ocean management. Analyzing water for DNA traces shed by organisms may aid assessment. Here we tested aquatic environmental DNA (eDNA as an indicator of fish presence in the lower Hudson River estuary. A checklist of local marine fish and their relative abundance was prepared by compiling 12 traditional surveys conducted between 1988-2015. To improve eDNA identification success, 31 specimens representing 18 marine fish species were sequenced for two mitochondrial gene regions, boosting coverage of the 12S eDNA target sequence to 80% of local taxa. We collected 76 one-liter shoreline surface water samples at two contrasting estuary locations over six months beginning in January 2016. eDNA was amplified with vertebrate-specific 12S primers. Bioinformatic analysis of amplified DNA, using a reference library of GenBank and our newly generated 12S sequences, detected most (81% locally abundant or common species and relatively few (23% uncommon taxa, and corresponded to seasonal presence and habitat preference as determined by traditional surveys. Approximately 2% of fish reads were commonly consumed species that are rare or absent in local waters, consistent with wastewater input. Freshwater species were rarely detected despite Hudson River inflow. These results support further exploration and suggest eDNA will facilitate fine-scale geographic and temporal mapping of marine fish populations at relatively low cost.

  11. Quantifying the effect of predators on endangered species using a bioenergetics approach : Caspian terns and juvenile salmonids in the Columbia River estuary

    NARCIS (Netherlands)

    Roby, DD; Lyons, DE; Craig, DP; Collis, K; Visser, GH

    We estimated the consumption of juvenile salmonids (Oncorhynchus spp.) and other forage fishes by Caspian terns (Sterna caspia) nesting on Rice Island in the Columbia River estuary in 1997 and 1998 using a bioenergetics modeling approach. The study was prompted by concern that Caspian tern predation

  12. 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...

  13. Dissolved inorganic carbon (DIC) and its δ13C in the Ganga (Hooghly) River estuary, India: Evidence of DIC generation via organic carbon degradation and carbonate dissolution

    Digital Repository Service at National Institute of Oceanography (India)

    Samanta, S.; Dalai, T.K.; Pattanaik, J.K.; Rai, S.K.; Mazumdar, A.

    to the oceans, which accounts for ca. 0.2% of the global river water flux. The results of this study suggest that estuaries in regions affected by tropical monsoon can be important in terms of their production of significant amounts of DIC and its delivery...

  14. Influence of filtration and glucose amendment on bacterial growth rate at different tidal conditions in the Minho Estuary River (NW Portugal)

    DEFF Research Database (Denmark)

    Anne, I.; Fidalgo, M. L.; Thosthrup, L.

    2006-01-01

    Bacterioplankton abundance, biomass and growth rates were studied in the Minho Estuary River (NW Portugal). The influence of tidal conditions, glucose amendment, and the filtration process on total bacterial abundance, total and faecal coliforms, as well as faecal streptococci, were evaluated...

  15. 226Ra behavior in the Pee Dee river-Winyah Bay estuary

    International Nuclear Information System (INIS)

    Elsinger, R.J.; Moore, W.S.

    1980-01-01

    Concentrations of dissolved 226 Ra in Winyah Bay, South Carolina, and in the adjacent Atlantic Ocean are augmented by the desorption of radium from sediments in the low-salinity area of the estuary and diffusion from bottom sediments. Desorption of 226 Ra is reflected by lower concentrations in suspended sediments from higher-salinity regions of the estuary. Bottom sediments from the high-salinity region have lower 226 Ra/ 230 Th activity ratios than those from the low-salinity end. (orig./ME)

  16. Estuarine Landcover Along the Lower Columbia River Estuary Determined from Compact Ariborne Spectrographic Imager (CASI) Imagery, Technical Report 2003.

    Energy Technology Data Exchange (ETDEWEB)

    Garono, Ralph; Robinson, Rob

    2003-10-01

    Developing an understanding of the distribution and changes in estuarine and riparian habitats is critical to the management of biological resources in the lower Columbia River. In a recently completed comprehensive ecosystem protection and enhancement plan for the lower Columbia River Estuary (CRE), Jerrick (1999) identified habitat loss and modification as one of the key threats to the integrity of the CRE ecosystem. This management plan called for an inventory of habitats as key first step in the CRE long-term restoration effort. While previous studies have produced useful data sets depicting habitat cover types along portions of the lower CRE (Thomas, 1980; Thomas, 1983; Graves et al., 1995; NOAA, 1997; Allen, 1999), no single study has produced a description of the habitats for the entire CRE. Moreover, the previous studies differed in data sources and methodologies making it difficult to merge data or to make temporal comparisons. Therefore, the Lower Columbia River Estuary Partnership (Estuary Partnership) initiated a habitat cover mapping project in 2000. The goal of this project was to produce a data set depicting the current habitat cover types along the lower Columbia River, from its mouth to the Bonneville Dam, a distance of {approx}230-km (Fig. 1) using both established and emerging remote sensing techniques. For this project, we acquired two types of imagery, Landsat 7 ETM+ and Compact Airborne Spectrographic Imager (CASI). Landsat and CASI imagery differ in spatial and spectral resolution: the Landsat 7 ETM+ sensor collects reflectance data in seven spectral bands with a spatial resolution of 30-m and the CASI sensor collects reflectance data in 19 bands (in our study) with a spatial resolution of 1.5-m. We classified both sets of imagery and produced a spatially linked, hierarchical habitat data set for the entire CRE and its floodplain. Landsat 7 ETM+ classification results are presented in a separate report (Garono et al., 2003). This report

  17. Effect of water-sediment regulation and its impact on coastline and suspended sediment concentration in Yellow River Estuary

    Directory of Open Access Journals (Sweden)

    Hai-bo Yang

    2017-10-01

    Full Text Available Implementation of the water-sediment regulation (WSR scheme, mainly focused on solving the sedimentation problems of reservoirs and the lower reaches of the Yellow River, has inevitably influenced the sediment distribution and coastal morphology of the Yellow River Estuary. Using coastline delineation and suspended sediment concentration (SSC retrieval methods, this study investigated water and sediment changes, identified detailed inter-annual and intra-annual variations of the coastline and SSC in the normal period (NP: 1986–2001, before and after the flood season and WSR period (WSRP: 2002–2013, before and after WSR. The results indicate that (1 the sedimentation in the low reaches of the Yellow River turned into erosion from 2002 onward; (2 the inter-annual coastline changes could be divided into an accretion stage (1986–1996, a slow erosion stage (1996–2002, and a slow accretion stage (2002–2013; (3 an intra-annual coastline extension occurred in the river mouth in most years of the WSRP; and (4 the mean intra-annual accretion area was 0.789 km2 in the NP and 4.73 km2 in the WSRP, and the mean SSC increased from 238 mg/L to 293 mg/L in the NP and from 192 mg/L to 264 mg/L in the WSRP.

  18. Eelgrass Enhancement and Restoration in the Lower Columbia River Estuary, Period of Performance: Feb 2008-Sep 2009.

    Energy Technology Data Exchange (ETDEWEB)

    Judd, C.; Thom, R; Borde, A. [Pacific Northwest National Laboratory

    2009-09-08

    The purpose of this study was to evaluate the ability to enhance distribution of eelgrass (Zostera marina) in the Columbia River Estuary to serve as refuge and feeding habitat for juvenile salmon, Dungeness crab, and other fish and wildlife. We strongly suspected that limited eelgrass seed dispersal has resulted in the present distribution of eelgrass meadows, and that there are other suitable places for eelgrass to survive and form functional meadows. Funded as part of the Bonneville Power Administration's call for Innovative Projects, we initiated a multistage study in 2008 that combined modeling, remote sensing, and field experimentation to: (1) Spatially predict habitat quality for eelgrass; (2) Conduct experimental plantings; and (3) Evaluate restoration potential. Baseline in-situ measurements and remote satellite observations were acquired for locations in the Lower Columbia River Estuary (LCRE) to determine ambient habitat conditions. These were used to create a habitat site-selection model, using data on salinity, temperature, current velocity, light availability, wave energy, and desiccation to predict the suitability of nearshore areas for eelgrass. Based on this model and observations in the field, five sites that contained no eelgrass but appeared to have suitable environmental conditions were transplanted with eelgrass in June 2008 to test the appropriateness of these sites for eelgrass growth. We returned one year after the initial planting to monitor the success rate of the transplants. During the year after transplanting, we carried out a concurrent study on crab distribution inside and outside eelgrass meadows to study crab usage of the habitat. One year after the initial transplant, two sites, one in Baker Bay and one in Young's Bay, had good survival or expansion rates with healthy eelgrass. Two sites had poor survival rates, and one site had a total loss of the transplanted eelgrass. For submerged aquatic vegetation (SAV) restoration

  19. Sediment-stabilizing and Destabilizing Ecoengineering Species from River to Estuary: the Case of the Scheldt System

    Science.gov (United States)

    Selakovic, S.; Cozzoli, F.; Leuven, J.; Van Braeckel, A.; Speybroeck, J.; Kleinhans, M. G.; Bouma, T.

    2017-12-01

    Interactions between organisms and landscape forming processes play an important role in evolution of coastal landscapes. In particular, biota has a strong potential to interact with important geomorphological processes such as sediment dynamics. Although many studies worked towards quantifying the impact of different species groups on sediment dynamics, information has been gathered on an ad hoc base. Depending on species' traits and distribution, functional groups of ecoengineering species may have differential effects on sediment deposition and erosion. We hypothesize that the spatial distributions of sediment-stabilizing and destabilizing species across the channel and along the whole salinity gradient of an estuary partly determine the planform shape and channel-shoal morphology of estuaries. To test this hypothesis, we analyze vegetation and macrobenthic data taking the Scheldt river-estuarine continuum as model ecosystem. We identify species traits with important effects on sediment dynamics and use them to form functional groups. By using linearized mixed modelling, we are able to accurately describe the distributions of the different functional groups. We observe a clear distinction of dominant ecosystem engineering functional groups and their potential effects on the sediment in the river-estuarine continuum. The first results of longitudinal cross section show the highest effects of stabilizing plant species in riverine and sediment bioturbators in weak polyhaline part of continuum. The distribution of functional groups in transverse cross sections shows dominant stabilizing effect in supratidal zone compared to dominant destabilizing effect in the lower intertidal zone. This analysis offers a new and more general conceptualization of distributions of sediment stabilizing and destabilizing functional groups and their potential impacts on sediment dynamics, shoal patterns, and planform shapes in river-estuarine continuum. We intend to test this in future

  20. Evaluation of the Ecotoxicity of Sediments from Yangtze River Estuary and Contribution of Priority PAHs to Ah Receptor-Mediated Activities

    Science.gov (United States)

    Liu, Li; Chen, Ling; Shao, Ying; Zhang, Lili; Floehr, Tilman; Xiao, Hongxia; Yan, Yan; Eichbaum, Kathrin; Hollert, Henner; Wu, Lingling

    2014-01-01

    In this study, in vitro bioassays were performed to assess the ecotoxicological potential of sediments from Yangtze River estuary. The cytotoxicity and aryl hydrocarbon receptor (AhR)-mediated toxicity of sediment extracts with rainbow trout (Oncorhynchus mykiss) liver cells were determined by neutral red retention and 7-ethoxyresorufin-O-deethylase assays. The cytotoxicity and AhR-mediated activity of sediments from the Yangtze River estuary ranged from low level to moderate level compared with the ecotoxicity of sediments from other river systems. However, Yangtze River releases approximately 14 times greater water discharge compared with Rhine, a major river in Europe. Thus, the absolute pollution mass transfer of Yangtze River may be detrimental to the environmental quality of estuary and East China Sea. Effect-directed analysis was applied to identify substances causing high dioxin-like activities. To identify unknown substances contributing to dioxin-like potencies of whole extracts, we fractionated crude extracts by open column chromatography. Non-polar paraffinic components (F1), weakly and moderately polar components (F2), and highly polar substances (F3) were separated from each crude extract of sediments. F2 showed the highest dioxin-like activities. Based on the results of mass balance calculation of chemical toxic equivalent concentrations (TEQs), our conclusion is that priority polycyclic aromatic hydrocarbons indicated a low portion of bio-TEQs ranging from 1% to 10% of crude extracts. Further studies should be conducted to identify unknown pollutants. PMID:25111307

  1. Evaluation of the ecotoxicity of sediments from Yangtze river estuary and contribution of priority PAHs to ah receptor--mediated activities.

    Science.gov (United States)

    Liu, Li; Chen, Ling; Shao, Ying; Zhang, Lili; Floehr, Tilman; Xiao, Hongxia; Yan, Yan; Eichbaum, Kathrin; Hollert, Henner; Wu, Lingling

    2014-01-01

    In this study, in vitro bioassays were performed to assess the ecotoxicological potential of sediments from Yangtze River estuary. The cytotoxicity and aryl hydrocarbon receptor (AhR)-mediated toxicity of sediment extracts with rainbow trout (Oncorhynchus mykiss) liver cells were determined by neutral red retention and 7-ethoxyresorufin-O-deethylase assays. The cytotoxicity and AhR-mediated activity of sediments from the Yangtze River estuary ranged from low level to moderate level compared with the ecotoxicity of sediments from other river systems. However, Yangtze River releases approximately 14 times greater water discharge compared with Rhine, a major river in Europe. Thus, the absolute pollution mass transfer of Yangtze River may be detrimental to the environmental quality of estuary and East China Sea. Effect-directed analysis was applied to identify substances causing high dioxin-like activities. To identify unknown substances contributing to dioxin-like potencies of whole extracts, we fractionated crude extracts by open column chromatography. Non-polar paraffinic components (F1), weakly and moderately polar components (F2), and highly polar substances (F3) were separated from each crude extract of sediments. F2 showed the highest dioxin-like activities. Based on the results of mass balance calculation of chemical toxic equivalent concentrations (TEQs), our conclusion is that priority polycyclic aromatic hydrocarbons indicated a low portion of bio-TEQs ranging from 1% to 10% of crude extracts. Further studies should be conducted to identify unknown pollutants.

  2. The hyperturbid state of the water column in estuaries and rivers: the importance of hindered settling

    Science.gov (United States)

    Dijkstra, Yoeri M.; Schuttelaars, Henk M.; Winterwerp, Johan C.

    2018-03-01

    Over the last few decades, some estuaries have undergone a transition to a hyperturbid state, characterised by suspended sediment concentrations of several grammes per litre averaged over the water column. To improve our understanding of this transition and of naturally hyperturbid estuaries, we systematically identify the processes allowing for high suspended sediment concentrations using a water column (1DV) model. Under a range of realistic forcing conditions, the state of the water column can be characterised by one of two equilibrium states. The first is an erosion-limited state, in which there still is sediment available for erosion at the bed. We find that this state only occurs with relatively low concentrations. The second is a supply-limited state, in which all erodable sediment is in suspension. The concentration in this state depends entirely on the amount of sediment in the system and can potentially be very high. We identify the conditions under which the state of the water column can jump from a low to a high concentration and identify hysteresis in the transition between the two states. The mechanism responsible for this hysteresis is hindered settling. It thus follows that hyperturbidity is only possible in a supply-limited state. From this observation we derive a necessary condition for an estuarine system to make the transition from low turbidity to hyperturbidity in a 1DV context. This is an important step towards understanding why some estuaries are hyperturbid and assessing the risk that particular estuaries may become hyperturbid in the future.

  3. The Bot River, a closed estuary in the south-western Cape

    African Journals Online (AJOL)

    and artificial opening of the estuary. The major primary .... Figure 2 shows the bathymetric chart of the lagoon. The ... part, while an erosion channel, developed from the artificial ... and there is no direct contact with the sea, no tidal effects occur.

  4. Petroleum hydrocarbons in a water-sediment system from Yellow River estuary and adjacent coastal area, China: Distribution pattern, risk assessment and sources.

    Science.gov (United States)

    Wang, Min; Wang, Chuanyuan; Li, Yuanwei

    2017-09-15

    Aliphatic hydrocarbons (AHs), biomarker and polycyclic aromatic hydrocarbons (PAHs) concentrations of surface water and sediment samples collected from Yellow River Estuary and adjacent coastal area in China were measured to determine their spatial distributions, analyze their sources and evaluate the ecological risk of PAHs in the water-sediment system. The spatial distributions of n-alkane in sediments are mainly controlled by the mixing inputs of terrigenous and marine components. In comparison with AHs, the total concentrations of Σ16PAHs in surface sediments from a transect of the offshore area were noticeably higher than that of the riverine and estuary areas. Additionally, the AHs and total PAHs concentrations all indicated an overall pattern of a seaward decrease. The PAHs concentrations during the dry season (mainly in the form of dissolved phase) were higher than that of PAHs (mainly dissolved phase and particulate phase form) in the flooding season. In comparison with global concentration levels of PAHs, the level of PAHs in suspended particulate matter and sediments from the Yellow River Estuary was lower than those from other countries, while the concentration of PAHs in the dissolved phase were in the middle range. Petroleum contamination, mainly from oil exploration and discharge of pollutants from rivers, was the main source of n-alkanes. The PAHs in the river were mostly of petrogenic origin, while those in the estuarial and marine areas originated mainly from pyrogenic sources. The results of the toxicology assessment suggested that the PAHs in sediments from Yellow River Estuary and adjacent coastal area exhibited a low potential eco-toxicological contamination level. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Mechanisms and Variability of Salt Transport in Partially-Stratified Estuaries

    National Research Council Canada - National Science Library

    Bowen, Melissa

    2000-01-01

    .... Analysis of salt transport from observations in the Hudson Estuary show that stratified periods with elevated estuarine salt transport occur in five-day intervals once a month during apogean neap tides...

  6. Parasitological survey of mangrove oyster, Crassostrea rhizophorae, in the Pacoti River Estuary, Ceará State, Brazil.

    Science.gov (United States)

    Sabry, Rachel Costa; Gesteira, Tereza Cristina Vasconcelos; Magalhães, Aimê Rachel Magenta; Barracco, Margherita Anna; Guertler, Cristhiane; Ferreira, Liana Pinho; Vianna, Rogério Tubino; da Silva, Patrícia Mirella

    2013-01-01

    The mangrove oyster, Crassostrea rhizophorae (Bivalvia, Ostreidae) is commonly collected by fisherwomen in the estuaries of the Ceará State (CE), Northeastern Brazil. Despite the socioeconomic importance of this natural resource, there are few studies on the health of the oysters in this region. This study aimed to survey pathological changes in the mangrove oyster C. rhizophorae in the estuary of the Pacoti River, CE. Adult oysters were collected in August 2008 (N=450) and December 2009 (N=450) at three sites of the Pacoti estuary and in 2010 (N=600) samplings were done quarterly at one site which has showed the higher prevalence de Perkinsus. Macroscopical and histological analyses were used to evaluate pathological changes, Ray's Fluid Thioglycollate Medium (RFTM) to detect Perkinsus spp. and polymerase chain reactions (PCR) and DNA sequencing to identify Perkinsus species. In 2009, RFTM assay detected Perkinsus sp. infecting the tissues of C. rhizophorae with low prevalences of 1.3%, 6.7% e 7.3% in sites 1, 2 and 3, respectively, and in 2010, in site 3, prevalence was 2% (12 of 600 oysters). PCR did not confirm any positive case in 2009 and only 5 in 2010. The phylogenetic analyses strongly indicate that the Perkinsus species infecting oysters C. rhizophorae of this study belongs to Perkinsus beihaiensis. The histology confirmed 11 cases of Perkinsus sp. infecting the C. rhizophorae in 2009, and only two cases in 2010. Nematopsis sp. was the protozoan observed with greater prevalence (up 96.7%). Other found protozoa were: Trichodina, Sphenophrya, Ancistrocoma - like and an unknown ovarian parasite. The metazoa found were the polychaete Polydora with high prevalences, a turbellarian, possibly of the genus Urastoma, an unidentified digenean metacercariae and larvae of cestode Tylocephalum. A continuous monitoring of diseases in bivalves from this natural population is recommended, since the phylogenetic analyses indicate the occurrence of P. beihaiensis

  7. Heavy metal accumulation during the last 30 years in the Karnaphuli River estuary, Chittagong, Bangladesh.

    Science.gov (United States)

    Wang, Ai-Jun; Kawser, Ahmed; Xu, Yong-Hang; Ye, Xiang; Rani, Seema; Chen, Ke-Liang

    2016-01-01

    Heavy metal contamination of aquatic environment has attracted global attention owing to its abundance, persistence, and environmental toxicity, especially in developing countries like Bangladesh. Five heavy metals, namely chromium (Cr), copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn) were investigated in surface and core sediments of the Karnaphuli River (KR) estuary in Chittagong, Bangladesh, in order to reveal the heavy metal contamination history in estuarine sediments and its response to catastrophic events and human activities. The surface sediment was predominantly composed of silt and sand, and the surface sediment was contaminated with Cr and Pb. Based on the 210 Pb chronology, the sedimentation rate in the inter-tidal zone of KR estuary was 1.02 cm/a before 2007, and 1.14 cm/a after 2008. The core sediment collected from 8 to 20 cm below the surface mainly originated from terrestrial materials induced by catastrophic events such as cyclone, heavy rainfall and landslides in 2007 and 2008. The values of contamination factor ( CF ) showed that the sediment became moderately contaminated with Cr and Pb in the last 30 years. The variation and accumulation of heavy metals in core sediment before 2000 was mainly related to natural variations in sediment sources; however, in subsequent years, the anthropogenic inputs of heavy metals have increased due to rapid physical growth of urban and industrial areas in the Chittagong city. In general, the accumulation pattern of heavy metals after normalization to Aluminum in sediments of KR estuary indicated an accelerated rate of urbanization and industrialization in the last 30 years, and also suggested the influence of natural catastrophic event on estuarine environment.

  8. Use of Reflectance Ratios as a Proxy for Coastal Water Constituent Monitoring in the Pearl River Estuary

    Directory of Open Access Journals (Sweden)

    Hong-Li Li

    2009-01-01

    Full Text Available Spectra, salinity, total suspended solids (TSS, in mg/L and colored dissolved organic matter (CDOM, ag(400 at 400 nm sampled in stations in 44 different locations on December 18, 19 and 21, in 2006 were measured and analyzed. The studied field covered a large variety of optically different waters, the absorption coefficient of CDOM ([ag(400] in m-1 varied between 0.488 and 1.41 m-1, and the TSS concentrations (mg/L varied between 7.0 and 241.1 mg/L. In order to detect salinity of the Pearl River Estuary, we analyzed the spectral properties of TSS and CDOM, and the relationships between field water reflectance spectra and water constituents’ concentrations based on the synchronous in-situ and satellite hyper-spectral image analysis. A good correlation was discovered (the positive correlation by linear fit, between in-situ reflectance ratio R680/R527 and TSS concentrations (R2 = 0.65 for the salinity range of 1.74-22.12. However, the result also showed that the absorption coefficient of CDOM was not tightly correlated with reflectance. In addition, we also observed two significant relationships (R2 > 0.77, one between TSS concentrations and surface salinity and the other between the absorption coefficient of CDOM and surface salinity. Finally, we develop a novel method to understand surface salinity distribution of estuarine waters from the calibrated EO-1 Hyperion reflectance data in the Pearl River Estuary, i.e. channels with high salinity and shoals with low salinity. The EO-1 Hyperion derived surface salinity and TSSconcentrations were validated using in-situ data that were collected on December 21, 2006, synchronous with EO-1 Hyperion satellite imagery acquisition. The results showed that the semi-empirical relationships are capable of predicting salinity from EO-1 Hyperion imagery in the Pearl River Estuary (RMSE < 2‰.

  9. Heavy metal fractions and ecological risk assessment in sediments from urban, rural and reclamation-affected rivers of the Pearl River Estuary, China.

    Science.gov (United States)

    Zhang, Guangliang; Bai, Junhong; Xiao, Rong; Zhao, Qingqing; Jia, Jia; Cui, Baoshan; Liu, Xinhui

    2017-10-01

    Rapid urbanization and reclamation processes in coastal areas have resulted in serious pollution to the aquatic environment. Less is known on the geochemical fractions and ecological risks in river sediment under various human activities pressures, which is essential for addressing the connections between heavy metal pollution and anthropogenic influences. River sediments were collected from different landscapes (i.e., urban, rural and reclamation areas) to investigate the impacts of urbanization and reclamation on the metallic pollution levels and ecological risks in the Pear River Estuary of China. Results showed that Cd, Zn and Cu with high total contents and geoaccumulation index (I geo ) were the primary metals in the Peal River sediments. Generally, urban river sediments, especially the surface sediment layer (0-10 cm), exhibited higher metallic pollution levels. As for geochemical fractions, reducible and residual fractions were the dominant forms for six determined metals. And the percentage of heavy metals bound to Fe-Mn oxides decreased with increasing soil depth but the reverse tendency was observed for residual fractions. Compared with rural river sediments, heavy metals were highly associated with the exchangeable and carbonate fractions in both urban and reclamation-affected river sediments, suggesting that anthropogenic activities mainly increased the active forms of metals. Approximately 80% of Cd existed in the non-residual fraction and posed medium to high ecological risk according to the risk assessment code (RAC) values. The redundancy analysis (RDA) revealed that both urbanization and reclamation processes would cause similar metallic characteristics, and sediment organic matter (SOC) might be the prominent influencing factor. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Arsenic speciation in water, suspended particles, and coastal organisms from the Taehwa River Estuary of South Korea

    International Nuclear Information System (INIS)

    Hong, Seongjin; Kwon, Hye-Ok; Choi, Sung-Deuk; Lee, Jung-Suk; Khim, Jong Seong

    2016-01-01

    Water, suspended particulate matter (SPM), and biota samples were collected from the Taehwa River Estuary to determine the distributions, partitioning, and bioaccumulation of arsenicals. Six forms of As were quantitated by the use of HPLC-ICP/MS. As was found mainly near urban and industrial areas, and inorganic As V was the predominant As form in both water and SPM. Particulate arsenicals were found at the greatest concentrations in coarse particles (> 180 μm), followed by medium (30–180 μm) and fine (0.45–30 μm) particles, in freshwater. Arsenical concentrations were similar across the three particle fractions in saltwater. Field-based distribution coefficient (K d ) values for As depended strongly on SPM, with a less robust dependence on salinity. Concentrations of As were greater in macroalgae than in marine animals, such as fishes, bivalves, crabs, shrimps, and gastropods. Overall, the results of the present study provide useful information on the behaviors and fate of arsenicals in an estuarine environment. - Highlights: •Concentrations of As were greater in industrial and urban areas than in suburban area. •The predominant form of As in water and suspended particles was inorganic As V . •Particle-size distributions of arsenicals differed between freshwater and saltwater. •The K d values for As depended strongly on the presence of SPMs along the estuary. •Greater concentrations of arsenicals were found in macroalgae than in marine animals.

  11. Effect of Migration Pathway on Travel Time and Survival of Acoustic-Tagged Juvenile Salmonids in the Columbia River Estuary

    Energy Technology Data Exchange (ETDEWEB)

    Harnish, Ryan A.; Johnson, Gary E.; McMichael, Geoffrey A.; Hughes, Michael S.; Ebberts, Blaine D.

    2012-02-01

    Off-channel areas (side channels, tidal flats, sand bars, and shallow-water bays) may serve as important migration corridors through estuarine environments for salmon and steelhead smolts. Relatively large percentages (21-33%) of acoustic-tagged yearling and subyearling Chinook salmon and steelhead smolts were detected migrating through off-channel areas of the Columbia River estuary in 2008. The probability of survival for off-channel migrants (0.78-0.94) was similar to or greater than the survival probability of main channel migrants (0.67-0.93). Median travel times were similar for all species or run types and migration pathways we examined, ranging from 1-2 d. The route used by smolts to migrate through the estuary may affect their vulnerability to predation. Acoustic-tagged steelhead that migrated nearest to avian predator nesting colonies experienced higher predation rates (24%) than those that migrated farthest from the colonies (10%). The use of multiple migration pathways may be advantageous to out-migrating smolts because it helps to buffer against high rates of mortality, which may occur in localized areas, and helps to minimize inter- and intraspecific competition.

  12. Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2009

    Energy Technology Data Exchange (ETDEWEB)

    Diefenderfer, Heida L.; Johnson, Gary E.; Sather, Nichole K.; Skalski, John R.; Dawley, Earl M.; Coleman, Andre M.

    2010-08-01

    This report describes the 2009 research conducted under the U.S. Army Corps of Engineers (USACE or Corps) project EST-09-P-01, titled “Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary.” The research was conducted by the Pacific Northwest National Laboratory, Marine Science Laboratory and Hydrology Group, in partnership with the University of Washington, School of Aquatic and Fishery Sciences, Columbia Basin Research, and Earl Dawley (NOAA Fisheries, retired). This Columbia River Fish Mitigation Program project, referred to as “Salmonid Benefits,” was started in FY 2009 to evaluate the state-of-the science regarding the ability to quantify the benefits to listed salmonids1 of habitat restoration actions in the lower Columbia River and estuary.

  13. Tidal current energy potential of Nalón river estuary assessment using a high precision flow model

    Science.gov (United States)

    Badano, Nicolás; Valdés, Rodolfo Espina; Álvarez, Eduardo Álvarez

    2018-05-01

    Obtaining energy from tide currents in onshore locations is of great interest due to the proximity to the points of consumption. This opens the door to the feasibility of new installations based on hydrokinetic microturbines even in zones of moderate speed. In this context, the accuracy of energy predictions based on hydrodynamic models is of paramount importance. This research presents a high precision methodology based on a multidimensional hydrodynamic model that is used to study the energetic potential in estuaries. Moreover, it is able to estimate the flow variations caused by microturbine installations. The paper also shows the results obtained from the application of the methodology in a study of the Nalón river mouth (Asturias, Spain).

  14. The 137Cs distribution in sediment profiles from the Yangtze River estuary: a comparison of modeling and experimental results

    International Nuclear Information System (INIS)

    Pan, S.M.; Xu, Y.H.; Wang, A.; Povinec, P.P.

    2012-01-01

    It has been generally accepted when estimating sedimentation rates using the 137 Cs dating method that the position of the 137 Cs maximum in a sediment profile represents the year 1963. In this paper we validated this approach by developing a model in which the annual 137 Cs global fallout flux for the Yangtze River estuary was established on the basis of the Tokyo flux corrected for precipitation rates observed in Shanghai. As the 137 Cs maxima in the sediment deposition profiles depend on the sedimentation rates, the sub-sampling intervals were calculated accordingly. Higher measured than the calculated values were found in some cores, what may be due to fluctuating sedimentation rates and an additional deposition of 137 Cs from land-based sources. The study provides useful information on the reliability of the measured 137 Cs maxima in sediment profiles frequently used for dating of sediments in marine (coastal regions, open seas) as well as in terrestrial (lakes) environments. (author)

  15. Relationships between pesticides and organic carbon fractions in sediments of the Danshui River estuary and adjacent coastal areas of Taiwan

    International Nuclear Information System (INIS)

    Hung, C.-C.; Gong, G.-C.; Chen, H.-Y.; Hsieh, H.-L.; Santschi, Peter H.; Wade, Terry L.; Sericano, Jose L.

    2007-01-01

    In order to understand the fate of pesticides in marine environments, concentrations of pesticides and different carbonaceous fractions were determined for surface sediments in the Danshui River and nearby coastal areas of Taiwan. The major compounds detected were tetrachlorobenzene, HCHs, chlordane, aldrin, DDDs, DDEs and DDTs. Total concentrations of pesticides in the sediments ranged from not detectable to 23 ng g -1 , with the maximum value detected near the discharge point of the marine outfall from the Pali sewage treatment plant. These results confirm that pesticides persist in estuarine and nearby coastal environments of the Danshui River well after their ban. Concentrations of total pesticides significantly correlate with concentrations of total organic carbon and black carbon in these sediments, suggesting that total organic carbon and black carbon regulate the distribution of trace organic pollutants in fluvial and coastal marine sediments. - Total organic carbon and black carbon regulate the distribution of trace organic pollutants in sediments of the Danshui River estuary and adjacent coastal areas of Taiwan

  16. Estimation of chlorophyll-a concentration in estuarine waters: case study of the Pearl River estuary, South China Sea

    International Nuclear Information System (INIS)

    Zhang Yuanzhi; Lin Hui; Chen, Chuqun; Chen Liding; Zhang Bing; Gitelson, Anatoly A

    2011-01-01

    The objective of this work is to estimate chlorophyll-a (chl-a) concentration in the Pearl River estuary in China. To test the performance of algorithms for the estimation of the chl-a concentration in these productive turbid waters, the maximum band ratio (MBR) and near-infrared-red (NIR-red) models are used in this study. Specific focus is placed on (a) comparing the ability of the models to estimate chl-a in the range 1-12 mg m -3 , which is typical for coastal and estuarine waters, and (b) assessing the potential of the Moderate Resolution Imaging Spectrometer (MODIS) and Medium Resolution Imaging Spectrometer (MERIS) to estimate chl-a concentrations. Reflectance spectra and water samples were collected at 13 stations with chl-a ranging from 0.83 to 11.8 mg m -3 and total suspended matter from 9.9 to 21.5 g m -3 . A close relationship was found between chl-a concentration and total suspended matter concentration with the determining coefficient (R 2 ) above 0.89. The MBR calculated in the spectral bands of MODIS proved to be a good proxy for chl-a concentration (R 2 > 0.93). On the other hand, both the NIR-red three-band model, with wavebands around 665, 700, and 730 nm, and the NIR-red two-band model (with bands around 665 and 700 nm) explained more than 95% of the chl-a variation, and we were able to estimate chl-a concentrations with a root mean square error below 1 mg m -3 . The two- and three-band NIR-red models with MERIS spectral bands accounted for 93% of the chl-a variation. These findings imply that the extensive database of MODIS and MERIS images could be used to quantitatively monitor chl-a in the Pearl River estuary.

  17. n-Alkanes in sediments from the Yellow River Estuary, China: Occurrence, sources and historical sedimentary record.

    Science.gov (United States)

    Wang, Shanshan; Liu, Guijian; Yuan, Zijiao; Da, Chunnian

    2018-04-15

    A total of 21 surface sediments from the Yellow River Estuary (YRE) and a sediment core from the abandoned Old Yellow River Estuary (OYRE) were analyzed for n-alkanes using gas chromatography-mass spectrometry (GC-MS). n-Alkanes in the range C 12 -C 33 and C 13 -C 34 were identified in the surface sediments and the core, respectively. The homologous series were mainly bimodal distribution pattern without odd/even predominance in the YRE and OYRE. The total n-alkanes concentrations in the surface sediments ranged from 0.356 to 0.572mg/kg, with a mean of 0.434mg/kg on dry wt. Evaluation of n-alkanes proxies indicated that the aliphatic hydrocarbons in the surface sediments were derived mainly from a petrogenic source with a relatively low contribution of submerged/floating macrophytes, terrestrial and emergent plants. The dated core covered the time period 1925-2012 and the mean sedimentation rate was ca. 0.5cm/yr. The total n-alkanes concentrations in the core ranged from 0.0394 to 0.941mg/kg, with a mean of 0.180mg/kg. The temporal evolution of n-alkanes reflected the historical input of aliphatic hydrocarbons and was consistent with local and regional anthropogenic activity. In general, the investigation on the sediment core revealed a trend of regional environmental change and the role of anthropogenic activity in environmental change. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Distribution and risk assessment of trace metals in sediments from Yangtze River estuary and Hangzhou Bay, China.

    Science.gov (United States)

    Li, Feipeng; Mao, Lingchen; Jia, Yubao; Gu, Zhujun; Shi, Weiling; Chen, Ling; Ye, Hua

    2018-01-01

    The Yangtze River estuary (YRE) and Hangzhou Bay (HZB) is of environmental significance because of the negative impact from industrial activities and rapid development of aquaculture on the south bank of HZB (SHZB) in recent years. This study investigated the distribution and risk assessments of trace metals (Cr, Cu, Zn, Hg, Pb, and Cd) accumulated in surface sediments by sampling in YRE, outer and south HZB. Copper and Zn concentration (avg. 35.4 and 98.7 mg kg -1 , respectively) in surface sediments were generally higher than the background suggesting a widespread of Cu and Zn in the coastal area of Yangtze River Delta. High concentrations of Cu (~ 42 mg kg -1 ), Zn (~ 111 mg kg -1 ), Cd (~ 0.27 mg kg -1 ), and Hg (~ 0.047 mg kg -1 ) were found in inner estuary of YRE and decreased offshore as a result of terrestrial input and dilution effect of total metal contents by "cleaner" sediments from the adjacent sea. In outer HZB, accumulation of terrestrial derived metal has taken place near the Zhoushan Islands. Increase in sediment metal concentration from the west (inner) to the east (outer) of SHZB gave rise to the input of fine-grained sediments contaminated with metals from outer bay. According the results from geoaccumulation index, nearly 75% of samples from YRE were moderately polluted (1.0 < I geo  < 2.0) by Cd. Cadmium and Hg contributed for 80~90% to the potential ecological risk index in the YRE and HZB, with ~ 72% sites in HZB under moderate risk (150 ≤ RI < 300) especially near Zhoushan Islands.

  19. A multi-band semi-analytical algorithm for estimating chlorophyll-a concentration in the Yellow River Estuary, China.

    Science.gov (United States)

    Chen, Jun; Quan, Wenting; Cui, Tingwei

    2015-01-01

    In this study, two sample semi-analytical algorithms and one new unified multi-band semi-analytical algorithm (UMSA) for estimating chlorophyll-a (Chla) concentration were constructed by specifying optimal wavelengths. The three sample semi-analytical algorithms, including the three-band semi-analytical algorithm (TSA), four-band semi-analytical algorithm (FSA), and UMSA algorithm, were calibrated and validated by the dataset collected in the Yellow River Estuary between September 1 and 10, 2009. By comparing of the accuracy of assessment of TSA, FSA, and UMSA algorithms, it was found that the UMSA algorithm had a superior performance in comparison with the two other algorithms, TSA and FSA. Using the UMSA algorithm in retrieving Chla concentration in the Yellow River Estuary decreased by 25.54% NRMSE (normalized root mean square error) when compared with the FSA algorithm, and 29.66% NRMSE in comparison with the TSA algorithm. These are very significant improvements upon previous methods. Additionally, the study revealed that the TSA and FSA algorithms are merely more specific forms of the UMSA algorithm. Owing to the special form of the UMSA algorithm, if the same bands were used for both the TSA and UMSA algorithms or FSA and UMSA algorithms, the UMSA algorithm would theoretically produce superior results in comparison with the TSA and FSA algorithms. Thus, good results may also be produced if the UMSA algorithm were to be applied for predicting Chla concentration for datasets of Gitelson et al. (2008) and Le et al. (2009).

  20. Pollution status of polycyclic aromatic hydrocarbons in surface sediments from the Yangtze River Estuary and its adjacent coastal zone.

    Science.gov (United States)

    Wang, Chenglong; Zou, Xinqing; Gao, Jianhua; Zhao, Yifei; Yu, Wenwen; Li, Yali; Song, Qiaochu

    2016-11-01

    Polycyclic aromatic hydrocarbons (PAHs) are mainly produced by incomplete combustion and are used as indicators of anthropogenic activities on the environment. This study analyses the PAHs level in the Yangtze River Estuary (YRE), an important component of Yangtze River and a developed and populated region in China. Surface sediments were collected from 77 sites at the YRE and its adjacent coastal zone (IACZ) for a comprehensive study of PAHs. Kriging interpolation technology and Positive matrix factorization (PMF) model were applied to explore the spatial distribution and sources of PAHs. Concentrations of 16 PAHs (ΣPAHs) varied from 27.2 ng g(-1) to 621.6 ng g(-1) dry weight, with an average value of 158.2 ng g(-1). Spatially, ΣPAHs exhibited wide fluctuation and exhibited an increasing tendency from north to south. In addition, ΣPAHs exhibited a decreasing trend with increasing distance between the estuary and IACZ. The deposition flux of PAHs indicated that more than 107.8 t a(-1) PAHs was deposited in the study area annually. The results of the PMF model revealed that anthropogenic activities were the main sources of PAHs in the study area. Vehicle emissions and marine engines were the most important sources and accounted for 40.9% of the pollution. Coal combustion, petrogenic sources, and wood combustion were other sources that contributed 23.9%, 23.6%, and 11.5%, respectively. The distribution patterns of PAHs in the YRE and IACZ were influenced by many complicated factors such as sediment grain size, hydrodynamics and so on. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Distribution, historical trends and inventories of polychlorinated biphenyls in sediments from Yangtze River Estuary and adjacent East China Sea

    International Nuclear Information System (INIS)

    Yang Huayun; Zhuo Shanshan; Xue Bin; Zhang Chunlong; Liu Weiping

    2012-01-01

    A large portion of polychlorinated biphenyls (PCBs) from e-waste released into the coastal areas may be the potential source of PCBs to the global oceans. The paper presents data of PCBs concentrations in fifty surface sediment samples and a dated sediment core in Yangtze River Delta (YRE) and adjacent East China Sea (ECS). The total PCBs levels varied from 5.08 to 19.64 ng/g dry weight, with the highest concentrations situate within the river-sea boundary zone which is so-called “marginal filter”. Concurrent with the operation of e-waste recycling over the last two decades, PCB fluxes started to rise again after 1980s and reached a maximum in this century. The full data set was used to estimate the burden of PCBs in YRE and adjacent ECS. A total sediment burdens were 192.8 tons, with the spatial density of 364 ng/cm 2 which accounts for 1.9% of all the PCBs in China. - Highlights: ► PCBs residues remained widespread in Yangtze River Delta and adjacent East China Sea. ► Highest PCBs concentrations situate within the river-sea boundary zone. ► Congener profiles and PCA highlight the influence of e-waste recycling. ► Temporal distributions indicated PCB fluxes reached a maximum in this century. ► Total sediment burdens accounts for 1.9 % of all the PCBs in China. - Spatial and temporal distributions of polychlorinated biphenyls have been delineated in sediments from Yangtze River Estuary and adjacent East China Sea.

  2. High CO2 emissions from the tropical Godavari estuary (India) associated with monsoon river discharges

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.; Kumar, N.A.; Prasad, V.R.; Venkataramana, V.; Appalanaidu, S.; Sridevi, B.; Kumar, B.S.K.; Bharati, M.D.; Subbaiah, C.V.; Acharyya, T.; Rao, G.D.; Viswanadham, R.; Gawade, L.; Manjary, D.T.; Kumar, P.P.; Rajeev, K.; Reddy, N.P.C.; Sarma, V.V.; Kumar, M.D.; Sadhuram, Y.; Murty, T.V.R.

    ). Air-water flux of CO 2 was estimated following Wanninkhof (1992) using measured wind speed. 3. Results and discussion The dam controlled freshwater discharge into the Godavari estuary was maximal in August (Fig. 2a). There was virtually... bacterioplankton. Appl. Environ. Microbiol.52,1298-1303. Lewis, E., and D.W.R. Wallace (1998). Program developed for CO2 system calculations. ORNL/CDIAC-105. Carbon dioxide information analysis center, Oak Ridge National Laboratory, U.S. Department of Energy...

  3. Distribution and pollution assessment of heavy metals in surface sediments in Xiaoqing river estuary and its adjacent sea of Laizhou bay

    Science.gov (United States)

    Wang, Li; Luo, Xianxiang; Fan, Yuqing

    2018-03-01

    In this paper, the monitoring results of four heavy metals Cu, Pb, Zn and Hg at 10 sampling stations in Xiaoqing river estuary and its adjacent sea of Laizhou Bay in November 2008 were analyzed and evaluated. The results showed that the concentrations of heavy metals in the steam channel and estuary are higher than those in the adjacent sea, and the metal concentrations were below the standard for I class of marine sediment quality, excepting the station 2 in the steam channel and station 5 in the estuary. The assessment of the single-factor pollution index showed that the overall pollution level of the study area was relatively low, but there was serious pollution phenomenon in individual station. The potential ecological risk of heavy metals in the surface sediments was generally at a low level, and Hg had the highest potential risk.

  4. Mathematical simulation of sediment and radionuclide transport in estuaries

    International Nuclear Information System (INIS)

    Onishi, Y.; Trent, D.S.

    1982-11-01

    The finite element model LFESCOT (Flow, Energy, Salinity, Sediment and Contaminant Transport Model) was synthesized under this study to simulate radionuclide transport in estuaries to obtain accurate radionuclide distributions which are affected by these factors: time variance, three-dimensional flow, temperature, salinity, and sediments. Because sediment transport and radionuclide adsorption/desorption depend strongly on sizes or types of sediments, FLESCOT simulates sediment and a sediment-sorbed radionuclide for the total of three sediment-size fractions (or sediment types) of both cohesive and noncohesive sediments. It also calculates changes of estuarine bed conditions, including bed elevation changes due to sediment erosion/deposition, and three-dimensional distributions of three bed sediment sizes and sediment-sorbed radionuclides within the bed. Although the model was synthesized for radionuclide transport, it is general enough to also handle other contaminants such as heavy metals, pesticides, or toxic chemicals. The model was checked for its capability for flow, water surface elevation change, salinity, sediment and radionuclide transport under various simple conditions first, confirming the general validity of the model's computational schemes. These tests also revealed that FLESCOT can use large aspect ratios of computational cells, which are necessary in handling long estuarine study areas. After these simple tests, FLESCOT was applied to the Hudson River estuary between Chelsea and the mouth of the river to examine how well the model can predict radionuclide transport through simulating tidally influenced three-dimensional flow, salinity, sediment and radionuclide movements with their interactions

  5. Benthic Bacillariophyta of the Paripe River estuary in Pernambuco state, Brazil

    Directory of Open Access Journals (Sweden)

    AN. Moura

    Full Text Available The aim of this study was to evaluate the benthic diatom composition from the estuary sediment in the Pernambuco State, based on 32 samples. Samples were collected monthly from September through December 1999 (dry period and from April through July 2000 (rainy period during four pre established sampling stations. Results indicated 19 families and 31 specific and infraspecific taxa. Eight new records were founded for Pernambuco State: Auliscus coelatus, Fallacia nummularia, Navicula algida, Plagiograma pulchellum, Terpsinoe americana, Triceratium antideluvianna and Tryblionella coarctata and one, Auliscus punctatus Bailey, in northeastern Brazil.

  6. Tracking historical lead pollution in the coastal area adjacent to the Yangtze River Estuary using lead isotopic compositions

    International Nuclear Information System (INIS)

    Hao Yunchao; Guo Zhigang; Yang Zuosheng; Fan, Dejiang; Fang Ming; Li Xiangdong

    2008-01-01

    The rapid economic development in the Yangtze River Delta (YRD), China in the last three decades has had a significant impact on the environment of the East China Sea (ECS). Lead isotopic compositions of a 210 Pb dated sediment core collected from the coastal ECS adjacent to the Yangtze River Estuary were analyzed to track the Pb pollution in the region. The baseline Pb concentration in the coastal ECS sediments before the industrialization in China was 32 μg g -1 , and the corresponding 206 Pb/ 207 Pb ratio was 1.195. The high-resolution profiles of Pb flux and 206 Pb/ 207 Pb ratios had close relationships with the economic development and the history of the use of leaded gasoline in China, and they were clearly different from those of most European countries and United States. - The combination of Pb concentration, sedimentary flux, Pb isotopic composition and 210 Pb dating in the coastal ECS sediments revealed the historical Pb pollution in China

  7. Feeding ecology and trophic relationships of fish species in the lower Guadiana River Estuary and Castro Marim e Vila Real de Santo António Salt Marsh

    Science.gov (United States)

    Sá, Rita; Bexiga, Constança; Veiga, Pedro; Vieira, Lina; Erzini, Karim

    2006-10-01

    In this study we analyze the feeding ecology and trophic relationships of some of the main fish species (Soleidae, Moronidae, Mullidae, Sparidae, Mugilidae, and Batrachoididae) of the lower Estuary of the Guadiana River and the Castro Marim e Vila Real de Santo António Salt Marsh. We examined the stomachs of 1415 fish caught monthly between September 2000 and August 2001. Feeding indices and coefficients were determined and used along with the results of multivariate analysis to develop diagrams of trophic interactions (food webs). Results show that these species are largely opportunistic predators. The most important prey items are amphipods, gobies (Gobiidae), shrimps ( Palaemon serratus and Crangon crangon), and polychaete worms. The lower Estuary and associated salt marshes are important nurseries and feeding grounds for the species studied. In this area, it is therefore important to monitor the effects of changes in river runoff, nutrient input, and temperature that result from construction of the Alqueva Dam upstream.

  8. Change characteristics of DSi and nutrition structure at the Yangtze River Estuary after Three Gorges Project impounding and their ecological effect

    Directory of Open Access Journals (Sweden)

    Li Lei

    2017-06-01

    Full Text Available The variation law of dissolved silica (DSi, dissolved inorganic nitrogen (DIN, dissolved inorganic phosphorus (DIP and nutrition structure after the Three Gorges Project (TGP impounding as well as their ecological effect were analyzed according to monitoring survey of the Yangtze River Estuary in spring (May and summer (August from 2004-2009. The results showed that after impounding, DSi and DIN concentration decreased and increased, respectively. During the study period, DSi decreased by about 63%, while DIN almost tripled. DIP concentration fluctuated slightly. With respect to nutrition structure, N:P increased, whereas Si:P and Si:N declined. According to chemometry standard of nutrient limits, nutrition structure tended to be imbalanced and the limiting factor of phytoplankton growth (P was studied. Changes of nutrition structure have largely decreased diatom and caused different composition of dominant phytoplankton species. This may change ecosystem structure of the Yangtze River Estuary.

  9. Metagenomic evidence for reciprocal particle exchange between the mainstem estuary and lateral bay sediments of the lower Columbia River

    Directory of Open Access Journals (Sweden)

    Mariya W Smith

    2015-10-01

    Full Text Available Lateral bays of the lower Columbia River estuary are areas of enhanced water retention that influence net ecosystem metabolism through activities of their diverse microbial communities. Metagenomic characterization of sediment microbiota from three disparate sites in two brackish lateral bays (Baker and Youngs produced approximately 100 Gbp of DNA sequence data analyzed subsequently for predicted SSU rRNA and peptide-coding genes. The metagenomes were dominated by Bacteria. A large component of Eukaryota was present in Youngs Bay samples, i.e. the inner bay sediment was enriched with the invasive New Zealand mudsnail, Potamopyrgus antipodarum, known for high ammonia production. The metagenome was also highly enriched with an archaeal ammonia oxidizer closely related to Nitrosoarchaeum limnia. Combined analysis of sequences and continuous, high-resolution time series of biogeochemical data from fixed and mobile platforms revealed the importance of large-scale reciprocal particle exchanges between the mainstem estuarine water column and lateral bay sediments. Deposition of marine diatom particles in sediments near Youngs Bay mouth was associated with a dramatic enrichment of Bacteroidetes (58% of total Bacteria and corresponding genes involved in phytoplankton polysaccharide degradation. The Baker Bay sediment metagenome contained abundant Archaea, including diverse methanogens, as well as functional genes for methylotrophy and taxonomic markers for syntrophic bacteria, suggesting that active methane cycling occurs at this location. Our previous work showed enrichments of similar anaerobic taxa in particulate matter of the mainstem estuarine water column. In total, our results identify the lateral bays as both sources and sinks of biogenic particles significantly impacting microbial community composition and biogeochemical activities in the estuary.

  10. In situ fate and partitioning of waterborne perfluoroalkyl acids (PFAAs) in the Youngsan and Nakdong River Estuaries of South Korea

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Seongjin [School of Earth and Environmental Sciences, Seoul National University, Seoul (Korea, Republic of); Khim, Jong Seong, E-mail: jskocean@snu.ac.kr [School of Earth and Environmental Sciences, Seoul National University, Seoul (Korea, Republic of); Park, Jinsoon [School of Earth and Environmental Sciences, Seoul National University, Seoul (Korea, Republic of); Kim, Minhee; Kim, Woong-Ki; Jung, Jinho; Hyun, Seunghun; Kim, Jeong-Gyu [Division of Environmental Science and Ecological Engineering, Korea University, Seoul (Korea, Republic of); Lee, Hyojin; Choi, Heeseon J. [Department of Environmental Chemistry and Ecology, GeoSystem Research Corporation, Gunpo (Korea, Republic of); Codling, Garry [Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, SK (Canada); Giesy, John P. [Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, SK (Canada); Department of Zoology, Center for Integrative Toxicology, Michigan State University, East Lansing, MI (United States); Department of Biology and Chemistry and State Key Laboratory in Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong, SAR (China)

    2013-02-15

    Concentrations, distributions, fate, and partitioning of perfluoroalkyl acids (PFAAs) were investigated in surface water (n = 34) collected from the Youngsan and Nakdong River Estuaries of South Korea. Thirteen individual PFAAs in water and suspended solids (SS) were quantified by use of HPLC–MS/MS. PFAAs were detected in all samples, which indicated that they were widely distributed in the study area. Greater concentrations of PFAAs were found at some inland sites which seemed to be affected by direct input from point sources, such as wastewater treatment plants, and/or indirect diffusive sources, such as surface runoff. Spatial distributions of PFAAs in estuaries along transects toward the open sea demonstrated that these chemicals were transported to the outer region primarily by water discharged during the rainy season. Field-based partition coefficients (K{sub d}) for long-chain PFAAs (C ≥ 8) were significantly correlated with salinity (r{sup 2} = 0.48 to 0.73, p < 0.01); K{sub d} values increased exponentially as a function of salinity. Due to the ‘salting-out’ effect, PFAAs were largely scavenged by adsorption onto SS and/or sediments in estuarine environments. In addition, values for K{sub d} of those PFAAs were directly proportional to the number of carbon atoms in the PFAAs. Salting constants of selected PFAAs were notably greater than those of other environmental organic contaminants, which indicated that adsorption of PFAAs is largely associated with salinity. Overall, the results of the present study will provide better understanding of the fate and transport of PFAAs in the zone of salinity boundary that can be used for developing fate models of PFAAs in the coastal marine environment. - Highlights: ► In situ fate and partitioning of PFAAs were described along salinity gradients in estuaries. ► Salinity was found to be the key factor controlling adsorption of waterborne PFAAs. ► The K{sub d} for longer-chain PFAAs (C ≥ 8) increased as

  11. Leven estuary project. Fisheries Department final report

    OpenAIRE

    Bayliss, B.D.

    1997-01-01

    This is the report on the Leven estuary project: Fisheries Department final report produced by the Environment Agency North West in 1997. This report contains information about Leven estuary, river Leven catchment, river Crake catchment and the Ulverston Discharges. The Leven estuary is characterised by being very shallow, and shares the extremely variable tides and currents that characterize the whole of Morecambe Bay. There was little detailed knowledge of the impact on the Leven estuary, a...

  12. Bacteria of fecal origin in mangrove oysters (Crassostrea rhizophorae) in the Cocó River estuary, Ceará State, Brazil

    OpenAIRE

    Silva,Ana I.M.; Vieira,Regine H.S.F.; Menezes,Francisca G.R.; Fonteles-Filho,Antonio A.; Torres,Regina C.O.; Sant'Anna,Ernani S.

    2004-01-01

    This study was aimed at evaluating the microbiological quality of mangrove oysters (Crassostrea rhizophorae), collected at a natural oyster bed in the estuary of Cocó river (Fortaleza, Ceará, Brazil). MPN values were used for estimating the total (TC) and fecal (FC) coliforms and Enterococcus spp. TC and FC MPN values in the whole muscle and intervalve liquid ranged from 1,600/g and from

  13. Study of the dynamic behaviour of the estuary of the Guadalquivir river

    International Nuclear Information System (INIS)

    Baonza, E.; Plata Bedmar, A.; Jimenez, J.A.; Ruiz Mateos, A.

    1979-01-01

    One of the largest rivers in Spain, the Guadalquivir, is showing signs of two types of contamination. The first is caused by effluents from industry and settlements on the river, which include Seville. The second is due to penetration by salt water from the Atlantic, which is carried more than 100km by tides. Both types of contamination, and especially the second, seriously affect the water collected for irrigating rice fields, which can tolerate a maximum salinity of 0.8g/l. The flow of fresh water carried by the river is regulated in its final stretch by the Alcala del Rio dam upstream from Seville. To determine the influence of variations in river discharge on the penetration of sea-water and on the dilution of salt water and contaminated water, twelve 82 Br point injections of 4Ci each were carried out at different spots; the passage of the radioactive cloud and its dilution were then monitored along the river. A single tritium injection of 30Ci was also made at the foot of the Alcala del Rio dam and the passage of the tracer was studied from three stations, the last of which was situated at the mouth of the river where it enters the Atlantic. The field data were used to prepare a mathematical model which yielded very interesting information, suggesting ways in which the use of the river could be improved. (author)

  14. Spatial and temporal distribution in density and biomass of two Pseudodiaptomus species (Copepoda: Calanoida in the Caeté river estuary (Amazon region - North of Brazil

    Directory of Open Access Journals (Sweden)

    A. Magalhães

    Full Text Available Spatial and temporal density and biomass distribution of the planktonic copepods Pseudodiaptomus richardi and P. acutus along a salinity gradient were investigated in the Caeté River Estuary (North-Brazil in June and December, 1998 (dry season and in February and May, 1999 (rainy season. Copepod biomass was estimated using regression parameters based on the relation of dry weight and body length (prosome of adult organisms. The Caeté River Estuary was characterized by high spatial and temporal variations in salinity (0.8-37.2‰. Exponential length-weight relationships were observed for both Pseudodiaptomus species. Density and biomass values oscillated between 0.28-46.18 ind. m-3 and 0.0022-0.3507 mg DW. m-3 for P. richardi; and between 0.01-17.02 ind. m-3 and 0.0005-0.7181 mg DW. m-3 for P. acutus. The results showed that the contribution of P. richardi for the secondary production in the Caeté River Estuary is more important in the limnetic zone than in other zones where euhaline-polyhaline regimes were predominant. However, it was not possible to observe a clear pattern of spatial and temporal distribution for P. acutus.

  15. Modeling the influence of river discharge on salt intrusion and residual circulation in Danshuei River estuary, Taiwan

    Science.gov (United States)

    Liu, W.-C.; Chen, W.-B.; Cheng, R.T.; Hsu, M.-H.; Kuo, A.Y.

    2007-01-01

    A 3-D, time-dependent, baroclinic, hydrodynamic and salinity model was implemented and applied to the Danshuei River estuarine system and the adjacent coastal sea in Taiwan. The model forcing functions consist of tidal elevations along the open boundaries and freshwater inflows from the main stream and major tributaries in the Danshuei River estuarine system. The bottom friction coefficient was adjusted to achieve model calibration and verification in model simulations of barotropic and baroclinic flows. The turbulent diffusivities were ascertained through comparison of simulated salinity time series with observations. The model simulation results are in qualitative agreement with the available field data. The validated model was then used to investigate the influence of freshwater discharge on residual current and salinity intrusion under different freshwater inflow condition in the Danshuei River estuarine system. The model results reveal that the characteristic two-layered estuarine circulation prevails most of the time at Kuan-Du station near the river mouth. Comparing the estuarine circulation under low- and mean flow conditions, the circulation strengthens during low-flow period and its strength decreases at moderate river discharge. The river discharge is a dominating factor affecting the salinity intrusion in the estuarine system. A correlation between the distance of salt intrusion and freshwater discharge has been established allowing prediction of salt intrusion for different inflow conditions. ?? 2007 Elsevier Ltd. All rights reserved.

  16. Temporal and spatial distributions of sediment total organic carbon in an estuary river.

    Science.gov (United States)

    Ouyang, Y; Zhang, J E; Ou, L-T

    2006-01-01

    Understanding temporal and spatial distributions of naturally occurring total organic carbon (TOC) in sediments is critical because TOC is an important feature of surface water quality. This study investigated temporal and spatial distributions of sediment TOC and its relationships to sediment contaminants in the Cedar and Ortega Rivers, Florida, USA, using three-dimensional kriging analysis and field measurement. Analysis of field data showed that large temporal changes in sediment TOC concentrations occurred in the rivers, which reflected changes in the characteristics and magnitude of inputs into the rivers during approximately the last 100 yr. The average concentration of TOC in sediments from the Cedar and Ortega Rivers was 12.7% with a maximum of 22.6% and a minimum of 2.3%. In general, more TOC accumulated at the upper 1.0 m of the sediment in the southern part of the Ortega River although the TOC sedimentation varied with locations and depths. In contrast, high concentrations of sediment contaminants, that is, total polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), were found in sediments from the Cedar River. There was no correlation between TOC and PAHs or PCBs in these river sediments. This finding is in contradiction to some other studies which reported that the sorption of hydrocarbons is highly related to the organic matter content of sediments. This discrepancy occurred because of the differences in TOC and hydrocarbon source input locations. It was found that more TOC loaded into the southern part of the Ortega River, while almost all of the hydrocarbons entered into the Cedar River. This study suggested that the locations of their input sources as well as the land use patterns should also be considered when relating hydrocarbons to sediment TOC.

  17. Drought and flood effects on macrobenthic communities in the estuary of Australia's largest river system

    Science.gov (United States)

    Dittmann, Sabine; Baring, Ryan; Baggalley, Stephanie; Cantin, Agnes; Earl, Jason; Gannon, Ruan; Keuning, Justine; Mayo, Angela; Navong, Nathavong; Nelson, Matt; Noble, Warwick; Ramsdale, Tanith

    2015-11-01

    Estuaries are prone to drought and flood events, which can vary in frequency and intensity depending on water management and climate change. We investigated effects of two different drought and flow situations, including a four year long drought (referred to as Millennium drought) and a major flood event, on the macrobenthic community in the estuary and coastal lagoon of the Murray Mouth and Coorong, where freshwater inflows are strictly regulated. The analysis is based on ten years of annual monitoring of benthic communities and environmental conditions in sediment and water. The objectives were to identify changes in diversity, abundance, biomass and distribution, as well as community shifts and environmental drivers for the respective responses. The Millennium drought led to decreased taxonomic richness, abundance and biomass of macrobenthos as hypersaline conditions developed and water levels dropped. More taxa were found under very high salinities than predicted from the Remane diagram. When a flood event broke the Millennium drought, recovery took longer than from a shorter drought followed by small flows. A flow index was developed to assess the biological response subject to the duration of the preceding drought and flow volumes. The index showed higher taxonomic richness, abundance and biomass at intermediate and more continuous flow conditions. Abundance increased quickly after flows were restored, but the benthic community was initially composed of small bodied organisms and biomass increased only after several years once larger organisms became more abundant. Individual densities and constancy of distribution dropped during the drought for almost all macrobenthic taxa, but recoveries after the flood were taxon specific. Distinct benthic communities were detected over time before and after the drought and flood events, and spatially, as the benthic community in the hypersaline Coorong was split off with a salinity threshold of 64 identified by LINKTREE

  18. Using fecal sterols to assess dynamics of sewage input in sediments along a human-impacted river-estuary system in eastern China.

    Science.gov (United States)

    He, Ding; Zhang, Kai; Tang, Jianhui; Cui, Xingqian; Sun, Yongge

    2018-05-01

    Sedimentary fecal sterols and other sterol biomarkers, combined with bulk total organic carbon (TOC) and its stable carbon isotope were applied to characterize the sewage contamination across a ca. 280 km transect from the Xiaoqing River to the Laizhou Bay, a typical river-estuary system subjected to extensive anthropogenic stress due to rapid regional urbanization and industrialization in eastern China. Two sampling events were performed in both spring and summer seasons in the Laizhou Bay adjacent to the Xiaoqing River in order to assess the potential seasonal variation. Fecal sterols such as coprostanol and epicoprostanol, which are typical indicators of anthropogenic sewage input, displayed high concentrations of up to 63.2 μg g -1 dry weight (dw) and 13.1 μg g -1 dw, respectively. Results suggested that most of the stations along the Xiaoqing River were severely contaminated by fecal inputs with a decreasing trend from the river to the estuary that was mainly explained by the increasing distance from the diffuse sewage sources and the gradual dilution by sea water. Although there was no significant difference in fecal sterol concentrations between spring and summer in the Laizhou Bay, suggestive of no significant difference in sewage abundance, significantly higher average epicoprostanol/coprostanol and lower coprostanol/epicoprostanol ratios were observed in spring than summer, indicative of different sewage sources (e.g., human vs. non-human). Seasonal discharge and land-runoff, air temperature related to microbial activity differences and different extend of animal manure irrigation during agricultural planting could be additional reasons and need further investigation. Nevertheless, fecal sterol concentrations, distributions and diagnostic ratios should all be taken into consideration to better understand sewage inputs and source dynamics in river-estuary ecosystems. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Behaviour of boron, calcium and magnesium in Mindola river estuary (Gujarat)

    Digital Repository Service at National Institute of Oceanography (India)

    Narvekar, P.V.; Zingde, M.D.; Dalal, V.N.K.

    percentage of removal of B at low chlorinities indicated its rapid removal in the initial encounter of river water with seawater. On the contrary, Ca was preferentially added at low chlorinities. Addition decreased as the chlorinity increased and removal...

  20. Estimation of chlorophyll-a concentration in estuarine waters: case study of the Pearl River estuary, South China Sea

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yuanzhi; Lin Hui [Institute of Space and Earth Information Science, Yuen Yuen Research Centre for Satellite Remote Sensing, Chinese University of Hong Kong, Shatin, N.T. (Hong Kong); Chen, Chuqun [South China Institute of Oceanology, Chinese Academy of Sciences, Guangzhou (China); Chen Liding [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing (China); Zhang Bing [Center for Earth Observation and Digital Earth, Chinese Academy of Sciences, Beijing (China); Gitelson, Anatoly A, E-mail: yuanzhizhang@cuhk.edu.hk [Center for Advanced Land Management Information Technologies (CALMIT), School of Natural Resources, University of Nebraska-Lincoln (United States)

    2011-04-15

    The objective of this work is to estimate chlorophyll-a (chl-a) concentration in the Pearl River estuary in China. To test the performance of algorithms for the estimation of the chl-a concentration in these productive turbid waters, the maximum band ratio (MBR) and near-infrared-red (NIR-red) models are used in this study. Specific focus is placed on (a) comparing the ability of the models to estimate chl-a in the range 1-12 mg m{sup -3}, which is typical for coastal and estuarine waters, and (b) assessing the potential of the Moderate Resolution Imaging Spectrometer (MODIS) and Medium Resolution Imaging Spectrometer (MERIS) to estimate chl-a concentrations. Reflectance spectra and water samples were collected at 13 stations with chl-a ranging from 0.83 to 11.8 mg m{sup -3} and total suspended matter from 9.9 to 21.5 g m{sup -3}. A close relationship was found between chl-a concentration and total suspended matter concentration with the determining coefficient (R{sup 2}) above 0.89. The MBR calculated in the spectral bands of MODIS proved to be a good proxy for chl-a concentration (R{sup 2} > 0.93). On the other hand, both the NIR-red three-band model, with wavebands around 665, 700, and 730 nm, and the NIR-red two-band model (with bands around 665 and 700 nm) explained more than 95% of the chl-a variation, and we were able to estimate chl-a concentrations with a root mean square error below 1 mg m{sup -3}. The two- and three-band NIR-red models with MERIS spectral bands accounted for 93% of the chl-a variation. These findings imply that the extensive database of MODIS and MERIS images could be used to quantitatively monitor chl-a in the Pearl River estuary.

  1. Concentrations and fluxes of dissolved uranium in the Yellow River estuary: seasonal variation and anthropogenic (Water-Sediment Regulation Scheme) impact

    International Nuclear Information System (INIS)

    Juanjuan, Sui; Zhigang, Yu; Bochao, Xu; Wenhua, Dong; Dong, Xia; Xueyan, Jiang

    2014-01-01

    The Water-Sediment Regulation Scheme (WSRS) of the Yellow River is a procedure implemented annually from June to July to expel sediments deposited in Xiaolangdi and other large middle-reach reservoirs and to scour the lower reaches of the river, by controlling water and sediment discharges. Dissolved uranium isotopes were measured in river waters collected monthly as well as daily during the 2010 WSRS (June 19–July 16) from Station Lijin (a hydrologic station nearest to the Yellow River estuary). The monthly samples showed dissolved uranium concentrations of 3.85–7.57 μg l −1 and 234 U/ 238 U activity ratios of 1.24–1.53. The concentrations were much higher than those reported for other global major rivers, and showed seasonal variability. Laboratory simulation experiments showed significant uranium release from bottom and suspended sediment. The uranium concentrations and activity ratios differed during the two stages of the WSRS, which may reflect desorption/dissolution of uranium from suspended river sediments of different origins. An annual flux of dissolved uranium of 1.04 × 10 8 g y −1 was estimated based on the monthly average water discharge and dissolved uranium concentration in the lower reaches of the Yellow River. The amount of dissolved uranium (2.65 × 10 7 g) transported from the Yellow River to the sea during the WSRS constituted about 1/4 of the annual flux. -- Highlights: • Dissolved U in the Yellow River estuary has distinct seasonal variability. • Geochemistry of dissolved U influenced by the WSRS has been analyzed. • Uranium flux during the WSRS has been evaluated

  2. Sources of suspended-sediment loads in the lower Nueces River watershed, downstream from Lake Corpus Christi to the Nueces Estuary, south Texas, 1958–2010

    Science.gov (United States)

    Ockerman, Darwin J.; Heitmuller, Franklin T.; Wehmeyer, Loren L.

    2013-01-01

    The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, Fort Worth District; City of Corpus Christi; Guadalupe-Blanco River Authority; San Antonio River Authority; and San Antonio Water System, developed, calibrated, and tested a Hydrological Simulation Program-FORTRAN (HSPF) watershed model to simulate streamflow and suspended-sediment concentrations and loads during 1958-2010 in the lower Nueces River watershed, downstream from Lake Corpus Christi to the Nueces Estuary in south Texas. Data available to simulate suspended-sediment concentrations and loads consisted of historical sediment data collected during 1942-82 in the study area and suspended-sediment concentration data collected periodically by the USGS during 2006-7 and 2010 at three USGS streamflow-gaging stations (08211000 Nueces River near Mathis, Tex. [the Mathis gage], 08211200 Nueces River at Bluntzer, Tex. [the Bluntzer gage], and 08211500 Nueces River at Calallen, Tex. [the Calallen gage]), and at one ungaged location on a Nueces River tributary (USGS station 08211050 Bayou Creek at Farm Road 666 near Mathis, Tex.). The Mathis gage is downstream from Wesley E. Seale Dam, which was completed in 1958 to impound Lake Corpus Christi. Suspended-sediment data collected before and after completion of Wesley E. Seale Dam provide insights to the effects of the dam and reservoir on suspended-sediment loads transported by the lower Nueces River downstream from the dam to the Nueces Estuary. Annual suspended-sediment loads at the Nueces River near the Mathis, Tex., gage were considerably lower for a given annual mean discharge after the dam was completed than before the dam was completed.

  3. Tidal wetlands of the Yaquina and Alsea River estuaries, Oregon: Geographic Information Systems layer development and recommendations for National Wetlands Inventory revisions

    Science.gov (United States)

    Brophy, Laura S.; Reusser, Deborah A.; Janousek, Christopher N.

    2013-01-01

    Geographic Information Systems (GIS) layers of current, and likely former, tidal wetlands in two Oregon estuaries were generated by enhancing the 2010 National Wetlands Inventory (NWI) data with expert local field knowledge, Light Detection and Ranging-derived elevations, and 2009 aerial orthophotographs. Data were generated for two purposes: First, to enhance the NWI by recommending revised Cowardin classifications for certain NWI wetlands within the study area; and second, to generate GIS data for the 1999 Yaquina and Alsea River Basins Estuarine Wetland Site Prioritization study. Two sets of GIS products were generated: (1) enhanced NWI shapefiles; and (2) shapefiles of prioritization sites. The enhanced NWI shapefiles contain recommended changes to the Cowardin classification (system, subsystem, class, and/or modifiers) for 286 NWI polygons in the Yaquina estuary (1,133 acres) and 83 NWI polygons in the Alsea estuary (322 acres). These enhanced NWI shapefiles also identify likely former tidal wetlands that are classified as upland in the current NWI (64 NWI polygons totaling 441 acres in the Yaquina estuary; 16 NWI polygons totaling 51 acres in the Alsea estuary). The former tidal wetlands were identified to assist strategic planning for tidal wetland restoration. Cowardin classifications for the former tidal wetlands were not provided, because their current hydrology is complex owing to dikes, tide gates, and drainage ditches. The scope of this project did not include the field evaluation that would be needed to determine whether the former tidal wetlands are currently wetlands, and if so, determine their correct Cowardin classification. The prioritization site shapefiles contain 49 prioritization sites totaling 2,177 acres in the Yaquina estuary, and 39 prioritization sites totaling 1,045 acres in the Alsea estuary. The prioritization sites include current and former (for example, diked) tidal wetlands, and provide landscape units appropriate for basin

  4. Occurrence of Cymbasoma longispinosum Bourne, 1890 (Copepoda: Monstrilloida in the Curuçá River estuary (Amazon Littoral

    Directory of Open Access Journals (Sweden)

    Natália R. Leite

    2010-09-01

    Full Text Available The present work was carried out to verify the occurrence and distribution of Cymbasoma longispinosum Bourne, 1890 in a tropical Amazon estuary from North Brazil. Samplings were performed bimonthly from July/2003 to July/2004 at two different transects (Muriá and Curuçá rivers situated along the Curuçá estuary (Pará, North Brazil. Samples were collected during neap tides via gentle (1 to 1.5 knots 200 μm-mesh net tows from a small boat. Additional subsurface water samples were collected for the determination of environmental parameters. Males and females of Cymbasoma longispinosum were only observed during September and November/2003. The highest number of organisms was found in September/2003 at the Muriá River transect. The presence of C. longispinosum in samples obtained during September and November/2003 could probably be related to the reproductive period of this species in the studied estuary, which is directly related to the dry period in the region. The highest salinity values and the highest number of individuals observed in September/2003 corroborate with the previous assumption, since no C. longispinosum was found during the months comprising the rainy period (January to June.O presente trabalho foi desenvolvido para verificar a ocorrência e distribuição de Cymbasoma longispinosum Bourne, 1890 em um estuário tropical amazônico da região norte do Brasil. As coletas foram realizadas bimestralmente de julho/2003 a julho/2004 em dois diferentes transectos (rios Muriá e Curuçá situados ao longo do estuário do Curuçá (Pará, Norte do Brasil. Amostras foram coletadas durante marés de quadratura por intermédio de arrastos com redes de plâncton de 200μm de abertura de malha, através de um pequeno barco a motor (1 a 1,5 knots. Amostras adicionais de água subsuperficial foram coletadas para determinação dos parâmetros ambientais. Machos e fêmeas de C. longispinosum foram observados apenas durante os meses de

  5. Fate of mercury species in the coastal plume of the Adour River estuary (Bay of Biscay, SW France)

    International Nuclear Information System (INIS)

    Sharif, Abubaker; Monperrus, Mathilde; Tessier, Emmanuel; Bouchet, Sylvain; Pinaly, Hervé; Rodriguez-Gonzalez, Pablo; Maron, Philippe; Amouroux, David

    2014-01-01

    Because mercury (Hg) undergoes significant biogeochemical processes along the estuarine-coastal continuum, the objective of this work was to investigate the distribution and reactivity of methylmercury (MeHg), inorganic mercury (Hg(II)) and gaseous Hg (DGM) in plume waters of the Adour River estuary (Bay of Biscay). Vertical profiles, spatial and tidal variability of Hg species concentrations were evaluated during two campaigns (April 2007 and May 2010) characterized by significant plume extents over the coastal zone. Incubations with isotopically enriched tracers were performed on bulk and filtered waters under sunlight or dark conditions to investigate processes involved in Hg methylation, demethylation and reduction rates. Total Hg(II) concentrations were more dispersed in April 2007 (5.2 ± 4.9 pM) than in May 2010 (2.5 ± 1.1 pM) while total MeHg concentrations were similar for both seasons and averaged 0.13 ± 0.07 and 0.18 ± 0.11 pM, respectively. DGM concentrations were also similar between the two campaigns, averaging 0.26 ± 0.10 and 0.20 ± 0.09 pM, respectively. Methylation yields remained low within the estuarine plume (< 0.01–0.4% day −1 ) while MeHg was efficiently demethylated via both biotic and abiotic pathways (2.3–55.3% day −1 ), mainly photo-induced. Hg reduction was also effective in these waters (0.3–43.5% day −1 ) and was occurring in both light and dark conditions. The results suggest that the plume is overall a sink for MeHg with integrated net demethylation rates, ranging from 2.0–3.7 g (Hg) d −1 , in the same range than the estimated MeHg inputs from the estuary (respectively, 0.9 and 3.5 g (Hg) d −1 ). The large evasion of DGM from the plume waters to the atmosphere (8.8–26.9 g (Hg) d −1 ) may also limit Hg T inputs to coastal waters (33–69 g (Hg) d −1 ). These processes are thus considered to be most significant in controlling the fate of Hg transferred from the river to the coastal zone. - Highlights:

  6. Fate of mercury species in the coastal plume of the Adour River estuary (Bay of Biscay, SW France)

    Energy Technology Data Exchange (ETDEWEB)

    Sharif, Abubaker; Monperrus, Mathilde; Tessier, Emmanuel; Bouchet, Sylvain; Pinaly, Hervé; Rodriguez-Gonzalez, Pablo [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l' Environnement et les Matériaux, UMR 5254 CNRS, Université de Pau et des Pays de l' Adour, Hélioparc Pau Pyrénées, 2 av. P. Angot, 64053 Pau cedex 9 (France); Maron, Philippe [Laboratoire des Sciences de l' Ingénieur Appliquées à la Mécanique et au Génie Electrique, Institut Supérieur Aquitain du Bâtiment et des Travaux Publics, Université de Pau et des Pays de l' Adour, Allée du Parc Montaury, 64600 Anglet (France); Amouroux, David, E-mail: david.amouroux@univ-pau.fr [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l' Environnement et les Matériaux, UMR 5254 CNRS, Université de Pau et des Pays de l' Adour, Hélioparc Pau Pyrénées, 2 av. P. Angot, 64053 Pau cedex 9 (France)

    2014-10-15

    Because mercury (Hg) undergoes significant biogeochemical processes along the estuarine-coastal continuum, the objective of this work was to investigate the distribution and reactivity of methylmercury (MeHg), inorganic mercury (Hg(II)) and gaseous Hg (DGM) in plume waters of the Adour River estuary (Bay of Biscay). Vertical profiles, spatial and tidal variability of Hg species concentrations were evaluated during two campaigns (April 2007 and May 2010) characterized by significant plume extents over the coastal zone. Incubations with isotopically enriched tracers were performed on bulk and filtered waters under sunlight or dark conditions to investigate processes involved in Hg methylation, demethylation and reduction rates. Total Hg(II) concentrations were more dispersed in April 2007 (5.2 ± 4.9 pM) than in May 2010 (2.5 ± 1.1 pM) while total MeHg concentrations were similar for both seasons and averaged 0.13 ± 0.07 and 0.18 ± 0.11 pM, respectively. DGM concentrations were also similar between the two campaigns, averaging 0.26 ± 0.10 and 0.20 ± 0.09 pM, respectively. Methylation yields remained low within the estuarine plume (< 0.01–0.4% day{sup −1}) while MeHg was efficiently demethylated via both biotic and abiotic pathways (2.3–55.3% day{sup −1}), mainly photo-induced. Hg reduction was also effective in these waters (0.3–43.5% day{sup −1}) and was occurring in both light and dark conditions. The results suggest that the plume is overall a sink for MeHg with integrated net demethylation rates, ranging from 2.0–3.7 g (Hg) d{sup −1}, in the same range than the estimated MeHg inputs from the estuary (respectively, 0.9 and 3.5 g (Hg) d{sup −1}). The large evasion of DGM from the plume waters to the atmosphere (8.8–26.9 g (Hg) d{sup −1}) may also limit Hg{sub T} inputs to coastal waters (33–69 g (Hg) d{sup −1}). These processes are thus considered to be most significant in controlling the fate of Hg transferred from the river to the

  7. Investigating the Impacts of Landuse-landcover (LULC Change in the Pearl River Delta Region on Water Quality in the Pearl River Estuary and Hong Kong’s Coast

    Directory of Open Access Journals (Sweden)

    Hongyan Xi

    2009-11-01

    Full Text Available Water quality information in the coastal region of Hong Kong and the Pearl River Estuary (PRE is of great concern to the local community. Due to great landuse-landcover (LULC changes with rapid industrialization and urbanization in the Pearl River Delta (PRD region, water quality in the PRE has worsened during the last 20 years. Frequent red tide and harmful algal blooms have occurred in the estuary and its adjacent coastal waters since the 1980s and have caused important economic losses, also possibly threatening to the coastal environment, fishery, and public health in Hong Kong. In addition, recent literature shows that water nutrients in Victoria Harbor of Hong Kong have been proven to be strongly influenced by both the Pearl River and sewage effluent in the wet season (May to September, but it is still unclear how the PRE diluted water intrudes into Victoria Harbor. Due to the cloudy and rainy conditions in the wet season in Hong Kong, ASAR images will be used to monitor the PRE river plumes and track the intruding routes of PRE water nutrients. In this paper, we first review LULC change in the PRD and then show our preliminary results to analyze water quality spatial and temporal information from remote observations with different sensors in the coastal region and estuary. The study will also emphasizes on time series of analysis of LULC trends related to annual sediment yields and critical source areas of erosion for the PRD region since the 1980s.

  8. The source of natural and anthropogenic heavy metals in the sediments of the Minjiang River Estuary (SE China): Implications for historical pollution

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yonghang, E-mail: yonghang_xu@163.com [Open Laboratory of Ocean and Coast Environmental Geology, Third Institute of Oceanography State Oceanic Administration, 178 Daxue Road, Xiamen 361005 (China); Sun, Qinqin [Fujian Provincial Key Laboratory of Coast and Island Management Technology Study, Fujian Institute of Oceanography, Xiamen 361013 (China); Yi, Liang [State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029 (China); Yin, Xijie; Wang, Aijun; Li, Yunhai; Chen, Jian [Open Laboratory of Ocean and Coast Environmental Geology, Third Institute of Oceanography State Oceanic Administration, 178 Daxue Road, Xiamen 361005 (China)

    2014-09-15

    Two sedimentary cores in the Minjiang River estuary (SE China) are documented for grain size, clay minerals, heavy metals, magnetic parameters and Pb isotopes to investigate the source and historical variation of heavy metals. The MJK9 core was collected outside of the Minjiang River estuary, and the core is composed of mixed sediments, of which ∼ 70% from the Yangtze River and 30% from the Minjiang River. It is thus difficult to be used for tracing the human activity along the Minjiang River. In contrast, the sediments of MJK16 core which was collected in a nearshore area are primarily from the Minjiang River. The enrichment factors of the sediments were < 1.5, indicating minor pollution. The results indicate that the sediments of the MJK16 core have Cu and Pb concentrations increasing since 1980, associated with the increase of magnetic mineral concentration and {sup 206}Pb/{sup 207}Pb and {sup 206}Pb/{sup 208}Pb of the sediments. We compared the Pb isotopic compositions between our results and those for the deposit mining in the Minjiang River basin, and aerosols and coal dust in south China, and considered that Pb in the sediments of the MJK16 core was derived primarily from weathered rocks as well as industrial emission (e.g. coal combustion). The sediments have anthropogenic Pb concentrations ranging from 6% in 1950 to 23.7% in 2010, consistent with the impact of rapid urban and industrial development in China. - Highlights: • Grain size, clay mineral and Pb isotope were used to identify sediment sources. • The contribution of Yangtze River to northern of Taiwan Strait was quantified. • Enrichment factors indicated Cu and Pb have increased over the last decades. • Coal combustion was the prevailing contamination source. • The anthropogenic Pb concentrations ranged from 6% in 1950 to 23.7% in 2010.

  9. The source of natural and anthropogenic heavy metals in the sediments of the Minjiang River Estuary (SE China): Implications for historical pollution

    International Nuclear Information System (INIS)

    Xu, Yonghang; Sun, Qinqin; Yi, Liang; Yin, Xijie; Wang, Aijun; Li, Yunhai; Chen, Jian

    2014-01-01

    Two sedimentary cores in the Minjiang River estuary (SE China) are documented for grain size, clay minerals, heavy metals, magnetic parameters and Pb isotopes to investigate the source and historical variation of heavy metals. The MJK9 core was collected outside of the Minjiang River estuary, and the core is composed of mixed sediments, of which ∼ 70% from the Yangtze River and 30% from the Minjiang River. It is thus difficult to be used for tracing the human activity along the Minjiang River. In contrast, the sediments of MJK16 core which was collected in a nearshore area are primarily from the Minjiang River. The enrichment factors of the sediments were < 1.5, indicating minor pollution. The results indicate that the sediments of the MJK16 core have Cu and Pb concentrations increasing since 1980, associated with the increase of magnetic mineral concentration and 206 Pb/ 207 Pb and 206 Pb/ 208 Pb of the sediments. We compared the Pb isotopic compositions between our results and those for the deposit mining in the Minjiang River basin, and aerosols and coal dust in south China, and considered that Pb in the sediments of the MJK16 core was derived primarily from weathered rocks as well as industrial emission (e.g. coal combustion). The sediments have anthropogenic Pb concentrations ranging from 6% in 1950 to 23.7% in 2010, consistent with the impact of rapid urban and industrial development in China. - Highlights: • Grain size, clay mineral and Pb isotope were used to identify sediment sources. • The contribution of Yangtze River to northern of Taiwan Strait was quantified. • Enrichment factors indicated Cu and Pb have increased over the last decades. • Coal combustion was the prevailing contamination source. • The anthropogenic Pb concentrations ranged from 6% in 1950 to 23.7% in 2010

  10. Biogeochemical alteration of dissolved organic material in the Cape Fear River Estuary as a function of freshwater discharge

    Science.gov (United States)

    Dixon, Jennifer L.; Helms, John R.; Kieber, Robert J.; Avery, G. Brooks

    2014-08-01

    This study presents the first extensive examination of the controls on optical properties of chromophoric dissolved organic matter (CDOM) within the Cape Fear River Estuary (CFRE) utilizing spectral slope ratios (SR). The application of SUVA254 values, absorption spectral slopes (S) and SR values has presented a distinct opportunity to observe compositional changes in CDOM in the CFRE that was not possible using bulk DOC and aCDOM(350) values alone. By comparing estuarine trends in CDOM spectral shape during both normal and historically low flow conditions, we found that diagenetic processing of CDOM in the CFRE is controlled primarily by riverine discharge rates. These findings suggest that the chromophoric fraction of DOM is altered during estuarine transport under low flow regimes but reaches the coastal ocean relatively unaltered under higher flow conditions. This highlights the tendency for autochthonous sources of DOC to offset photochemical losses and indicates that in situ DOC production can significantly contribute to the overall carbon load if discharge is low or sufficient biogeochemical alteration of the terrestrial DOM end-member occurs. This provides new insight into the usefulness of these optical properties into understanding the cycling, fate and transport of CDOM to the coastal ocean. SR values provide a simple but potentially powerful tool in understanding the flux, transport and impact of terrestrially derived organic material deposited in the coastal ocean.

  11. Brominated flame retardants in mangrove sediments of the Pearl River Estuary, South China: spatial distribution, temporal trend and mass inventory.

    Science.gov (United States)

    Zhang, Zai-Wang; Sun, Yu-Xin; Sun, Kai-Feng; Xu, Xiang-Rong; Yu, Shen; Zheng, Tian-Ling; Luo, Xiao-Jun; Tian, Yun; Hu, Yong-Xia; Diao, Zeng-Hui; Mai, Bi-Xian

    2015-03-01

    Sediments were collected from three mangrove wetlands in the Pearl River Estuary (PRE) of South China to investigate spatial and temporal distributions of polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE). Concentrations of ΣPBDEs, DBDPE and BTBPE in mangrove sediments of the PRE ranged from 1.25-206, 0.364-34.9, and not detected-0.794 ng g(-1) dry weight, respectively. The highest concentrations of ΣPBDEs, DBDPE and BTBPE were found at the mangrove wetland from Shenzhen, followed by Zhuhai and Guangzhou, showing the dependence on the proximity to urban areas. PBDEs were the predominant brominated flame retardants (BFRs) in mangrove sediments. The concentrations of ΣPBDEs, DBDPE and BTBPE in sediment cores showed an increasing trend from the bottom to top layers, reflecting the increasing usage of these BFRs. The inventories of ΣPBDEs, DBDPE and BTBPE in mangrove sediments were 1962, 245, and 4.10 ng cm(-2), respectively. This is the first study to report the occurrence of DBDPE and BTBPE in mangrove ecosystems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Non-aromatic hydrocarbons in surface sediments near the Pearl River estuary in the South China Sea

    International Nuclear Information System (INIS)

    Gao Xuelu; Chen Shaoyong; Xie Xueliang; Long Aimin; Ma Fujun

    2007-01-01

    Surface sediment samples at 4 sites along an offshore transect from outer continental shelf off the Pearl River estuary to the shelf slope region of the northern South China Sea, have been analyzed for total organic carbon (TOC), total nitrogen (TN), solvent extractable organic matter (EOM) and non-aromatic hydrocarbons. TOC, TN and EOM show distinct spatial variations. Their highest values are all recorded at the shelf slope region. EOM varies from 18.70-38.58 μg g -1 dry sediment and accounts for 0.20-0.72% of the TOC contents. The non-aromatic hydrocarbons are an important fraction of EOM. Their contents range from 3.43-7.06 μg g -1 dry sediment. n-Alkanes with carbon number ranging from 15-38 are identified. They derive from both biogenic and petrogenic sources in different proportions. Results of isoprenoid hydrocarbons, hopanes and steranes also suggest possible petroleum contamination. - Anthropogenic activities have influences on the composition of non-aromatic hydrocarbons in the surface sediments of the northern South China Sea outer continental shelf

  13. Parasites in the mangrove oyster Crassostrea rhizophorae cultivated in the estuary of the Graciosa River in Taperoá, Bahia.

    Science.gov (United States)

    Cova, Aliane Watanabe; Serafim Júnior, Moacyr; Boehs, Guisla; Souza, Jackson Moreira de

    2015-01-01

    In this work, parasites associated with the mangrove oyster Crassostrea rhizophorae were studied at a cultivation unit in the estuary of the Graciosa River in Taperoá, Bahia. On a monthly basis, between April 2011 and March 2012, 20 oysters were collected, measured and fixed in 10% formaldehyde. In order to identify the parasites, routine histological techniques were used. The specimens were embedded in paraffin and sections, 7 µm thick, were cut. These were then stained with Harris hematoxylin and eosin and were examined using an optical microscope. The parameters analyzed to investigate water quality showed that the temperature ranged from 23.9 °C to 29.3 °C, water salinity from 0.4 to 24.2 Practical Salinity Units PSU and recorded rainfall from 80 mm to 406.4 mm/month. During the parasitological analyses, infestation of the polychaete Neanthes succinea was observed in 41% of the oysters. Through histological techniques, the following parasites were identified: colonies of Rickettsia-like organisms (RLOs); the protozoa Nematopsis sp. and Ancistrocoma sp.; the turbellarian Urastoma sp.; the metacestode Tylocephalum sp. and an unidentified tapeworm. The data collected showed that there was low-intensity infection with and prevalence of parasites, except for Nematopsis sp., thus attesting that these cultivated oysters were in a healthy condition.

  14. First record of parasitism in the mangrove oyster Crassostrea rhizophorae (Bivalvia: Ostreidae at Jaguaribe River estuary - Ceará, Brazil

    Directory of Open Access Journals (Sweden)

    RC Sabry

    Full Text Available Mangrove oysters Crassostrea rhizophorae were sampled monthly in the estuary of Jaguaribe River, on the east coast of Ceará State, Brazil, between August, 2000 and December, 2001, making up 170 individuals. The water temperature varied from 26 to 30 °C and salinity from 21 to 42‰. The animals' size ranged from 3.4 to 7.2 cm height. Macroscopical and histopathological analyses were carried out in the oysters' tissues. The histological exams showed protozoans and metazoans of genera Nematopsis and Tylocephalum, respectively. Nematopsis prevalence varied from 60 to 100% and it was higher in the gills and mantle. The oocysts presented a mean size of 11.5 µm (±1.32 length and 9.1 µm (±1.06 width (n = 30, up to 3 oocysts/phagocyte having been observed. Several animals presented focal hemocitical reaction. The percentage of Tylocephalum was 1.7%. In spite of the high infection prevalence by Nematopsis, infected animals did not have their reproductive cycle impaired.

  15. Parasites in the mangrove oyster Crassostrea rhizophorae cultivated in the estuary of the Graciosa River in Taperoá, Bahia

    Directory of Open Access Journals (Sweden)

    Aliane Watanabe Cova

    Full Text Available In this work, parasites associated with the mangrove oyster Crassostrea rhizophorae were studied at a cultivation unit in the estuary of the Graciosa River in Taperoá, Bahia. On a monthly basis, between April 2011 and March 2012, 20 oysters were collected, measured and fixed in 10% formaldehyde. In order to identify the parasites, routine histological techniques were used. The specimens were embedded in paraffin and sections, 7 µm thick, were cut. These were then stained with Harris hematoxylin and eosin and were examined using an optical microscope. The parameters analyzed to investigate water quality showed that the temperature ranged from 23.9 °C to 29.3 °C, water salinity from 0.4 to 24.2 Practical Salinity Units PSU and recorded rainfall from 80 mm to 406.4 mm/month. During the parasitological analyses, infestation of the polychaete Neanthes succinea was observed in 41% of the oysters. Through histological techniques, the following parasites were identified: colonies of Rickettsia-like organisms (RLOs; the protozoa Nematopsis sp. and Ancistrocoma sp.; the turbellarian Urastoma sp.; the metacestode Tylocephalum sp. and an unidentified tapeworm. The data collected showed that there was low-intensity infection with and prevalence of parasites, except for Nematopsis sp., thus attesting that these cultivated oysters were in a healthy condition.

  16. Occurrence, distribution, and sources of emerging organic contaminants in tropical coastal sediments of anthropogenically impacted Klang River estuary, Malaysia.

    Science.gov (United States)

    Omar, Tuan Fauzan Tuan; Aris, Ahmad Zaharin; Yusoff, Fatimah Md; Mustafa, Shuhaimi

    2018-06-01

    This baseline assessment reports on the occurrence, distribution, and sources of emerging organic contaminants (EOCs) in tropical coastal sediments of anthropogenically impacted Klang River estuary, Malaysia. Bisphenol A was the highest concentration detected at 16.84 ng g -1 dry weight, followed by diclofenac (13.88 ng g -1 dry weight) and E1 (12.47 ng g -1 dry weight). Five compounds, namely, amoxicillin, progesterone, diazinon, bisphenol A, and E1, were found in all sampling stations assessed, and other compounds such as primidone, diclofenac, testosterone, E2, and EE2 were ubiquitously present in sediment samples, with percentage of detection range from 89.04% to 98.38%. Organic carbon content and pH were the important factors controlling the fate of targeted compounds in the tropical estuarine sediment. On the basis of the literature from other studies, the sources of EOCs are thought to be from wastewater treatment plants, domestic/medical waste discharge, livestock activities, industrial waste discharge, and agricultural activities. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Valuing Ecosystem Services with Fishery Rents: A Lumped-Parameter Approach to Hypoxia in the Neuse River Estuary

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    Larry B. Crowder

    2011-11-01

    Full Text Available Valuing ecosystem services with microeconomic underpinnings presents challenges because these services typically constitute nonmarket values and contribute to human welfare indirectly through a series of ecological pathways that are dynamic, nonlinear, and difficult to quantify and link to appropriate economic spatial and temporal scales. This paper develops and demonstrates a method to value a portion of ecosystem services when a commercial fishery is dependent on the quality of estuarine habitat. Using a lumped-parameter, dynamic open access bioeconomic model that is spatially explicit and includes predator-prey interactions, this paper quantifies part of the value of improved ecosystem function in the Neuse River Estuary when nutrient pollution is reduced. Specifically, it traces the effects of nitrogen loading on the North Carolina commercial blue crab fishery by modeling the response of primary production and the subsequent impact on hypoxia (low dissolved oxygen. Hypoxia, in turn, affects blue crabs and their preferred prey. The discounted present value fishery rent increase from a 30% reduction in nitrogen loadings in the Neuse is $2.56 million, though this welfare estimate is fairly sensitive to some parameter values. Surprisingly, this number is not sensitive to initial conditions.

  18. Spatiotemporal Trends of Heavy Metals in Indo-Pacific Humpback Dolphins (Sousa chinensis) from the Western Pearl River Estuary, China.

    Science.gov (United States)

    Gui, Duan; Yu, Ri-Qing; Karczmarski, Leszek; Ding, Yulong; Zhang, Haifei; Sun, Yong; Zhang, Mei; Wu, Yuping

    2017-02-07

    We assessed the spatiotemporal trends of the concentrations of 11 heavy metals (HMs) in the liver and kidney of Indo-Pacific humpback dolphins (Sousa chinensis) from western Pearl River Estuary (PRE) during 2004-2015. The hepatic levels of Cr, As, and Cu in these dolphins were among the highest reported for cetaceans globally, and the levels of Zn, Cu, and Hg were sufficiently high to cause toxicological effects in some of the animals. Between same age-sex groups, dolphins from Lingdingyang were significantly more contaminated with Hg, Se, and V than those from the West-four region, while the opposite was true for Cd. Generalized additive mixed models showed that most metals had significant but dissimilar temporal trends over a 10-year period. The concentrations of Cu and Zn increased significantly in recent years, corresponding to the high input of these metals in the region. Body-length-adjusted Cd levels peaked in 2012, accompanied by the highest annual number of dolphin stranding events. In contrast to the significant decrease in HM levels in the dolphins in Hong Kong waters (the eastern reaches of the PRE), the elevated metal exposure in the western PRE raises serious concerns.

  19. Trace metal distribution in sediments of the Pearl River Estuary and the surrounding coastal area, South China

    International Nuclear Information System (INIS)

    Ip, Carman C.M.; Li Xiangdong; Zhang Gan; Wai, Onyx W.H.; Li, Y.-S.

    2007-01-01

    Surface sediments and sediment cores collected at the Pearl River Estuary (PRE) and its surrounding coastal area were analysed for total metal concentrations, chemical partitioning, and Pb isotopic compositions. The distribution of Cu, Cr, Pb, and Zn demonstrated a typical diffusion pattern from the land to the direction of the sea. Two hotspots of trace metal contamination were located at the mixed zone between freshwater and marine waters. The enrichment of metals in the sediments could be attributed to the deposition of the dissolved and particulate trace metals in the water column at the estuarine area. The similar Pb isotopic signatures of the sediments at the PRE and its surrounding coastal area offered strong evidence that the PRE was a major source of trace metals to the adjacent coastal area. Slightly lower 206 Pb/ 207 Pb ratios in the coastal sediments may indicate other inputs of Pb in addition to the PRE sources, including the inputs from Hong Kong and other parts of the region. - The distribution of trace metals in sediments reflected contaminant sources, physical and chemical deposition processes

  20. Proceedings of the Columbia River Estuary Conference on Ecosystem Restoration, April 29-30, 2008, Astoria, Oregon.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E. [Pacific Northwest National Laboratory; Sutherland, G. Bruce [Oregon Department of Environmental Quality (retired)

    2008-09-29

    The 2008 Columbia River Estuary Conference was held at the Liberty Theater in Astoria, Oregon, on April 19-20. The conference theme was ecosystem restoration. The purpose of the conference was to exchange data and information among researchers, policy-makers, and the public, i.e., interrelate science with management. Conference organizers invited presentations synthesizing material on Restoration Planning and Implementation (Session 1), Research to Reduce Restoration Uncertainties (Session 2), Wetlands and Flood Management (Session 3), Action Effectiveness Monitoring (Session 4), and Management Perspectives (Session 5). A series of three plenary talks opened the conference. Facilitated speaker and audience discussion periods were held at the end of each session. Contributed posters conveyed additional data and information. These proceedings include abstracts and notes documenting questions from the audience and clarifying answers from the presenter for each talk. The proceedings also document key points from the discussion periods at the end of each session. The conference program is outlined in the agenda section. Speaker biographies are presented in Appendix A. Poster titles and authors are listed in Appendix B. A list of conference attendees is contained in Appendix C. A compact disk, attached to the back cover, contains material in hypertext-markup-language from the conference website (http://cerc.labworks.org/) and the individual presentations.

  1. Postlarval development of Halicarcinus planatus females (Crustacea, Decapoda, Hymenosomatidae in the estuary of the Deseado River, Argentina

    Directory of Open Access Journals (Sweden)

    Julio H. Vinuesa

    2008-03-01

    Full Text Available This study analyses morphology and morphometric growth changes of Halicarcinus planatus females until their terminal moult, and characterises new juvenile stages. Monthly samples were collected in the estuary of the Deseado River, Santa Cruz Province, Argentina. Crabs were sampled between the mid-intertidal and upper subtidal levels. Intermoult stages were analysed in sub-samples of adolescents and adults, and the presence of epizoic organisms was registered. Juveniles and adults were reared at the laboratory and examined for moult changes. All 3376 crabs caught were females, indicating a clear spatial segregation between sexes. Five juvenile stages (immature 1, 2, 3, 4 and adolescent and a mature one were recognised on the basis of morphology and morphometry. All immature stages differed in cephalothorax width (CW and abdomen width (AW. Positive allometry was observed in some juvenile stages and isometry in an immature stage and in mature females. Adolescents and adults encompassed a wide range of sizes, and the considerable size overlap between them suggests an anomalous growth process. Moult staging analysis indicated that adolescents have a high incidence of pre-moult stages in winter, when the terminal moult occurs. The measurements performed in laboratory-reared females indicated no abnormal increases during the moult. The terminal moult occurs within a wide size range, perhaps in association with mating.

  2. Import and export fluxes of macrozooplankton are taxa- and season-dependent at Jiuduansha marsh, Yangtze River estuary

    Science.gov (United States)

    Qin, Haiming; Sheng, Qiang; Chu, Tianjiang; Wang, Sikai; Wu, Jihua

    2015-09-01

    Macrozooplankton may play important roles in influencing nutrient exchange between salt marsh and nearby estuarine ecosystems through predator-prey interactions and their transport by tidal flows. In this study, macrozooplankton transport through year-round monthly sampling was investigated in a salt marsh creek of the Yangtze River estuary. Twenty-one orders of macrozooplankton were captured. Calanoida and Decapoda were dominant and numerically comprised 59.59% and 37.59% respectively of the total captured macrozooplankton throughout the year. Decapoda mainly occurred in April, May and June. In other months, the Calanoida contributed over 90% of the total individuals. The annual Ferrari index (I) for total individual number of macrozooplankton was 0.27, which generally supports the viewpoint that salt marshes are sources of zooplankton. The salt marsh was mainly a source for decapods and mysids, possibly because of larval release in their breeding seasons. The marsh was also a source for amphipods, probably because some benthic forms became transient planktonic forms during tidal water flushing. Copepods and fish larvae exhibited net import into the salt marsh, which may result from predation from salt marsh settlers or retention in the salt marsh. Monthly Ferrari index (I) estimations revealed that the role of the salt marsh as a sink or source of macrozooplankton was time-dependent, which is related to the life history of animals. This study showed that whether the salt marsh zooplankton act as energy importers or exporters is group/taxa-dependent and time-dependent.

  3. Ducks change wintering patterns due to changing climate in the important wintering waters of the Odra River Estuary

    Directory of Open Access Journals (Sweden)

    Domini