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Sample records for inhabiting estuarine waters

  1. The inhabitants of the spring ice, under-ice water, and sediments of the white sea in the estuarine zone of the Severnaya Dvina River

    Science.gov (United States)

    Sazhin, A. F.; Sapozhnikov, F. V.; Rat'kova, T. N.; Romanova, N. D.; Shevchenko, V. P.; Filippov, A. S.

    2011-04-01

    The data on the supra-ice snow, ice, under-ice water, and benthic algal flora obtained in 2007-2008 by sampling in the estuary of the Severnaya Dvina River are analyzed. The river ice and under-ice water in the estuarine zone and in the channel part of the Severnaya Dvina differed greatly in the algal flora's composition. The fresh water species never exceeded 8.6%, while the ice algae composed 90-96% of the total ice inhabitants' biomass. In the under-ice water, this value did not exceed 58-64%. The bacteria in the ice composed not more than 2.5-10% of the total biomass, while, in the under-ice water, 36-49%. The shares of ciliates (0.04%) and nematodes (0.005-1.6%) in the total biomass were negligible. In the estuarine zone, the ice was inhabited mainly by nematodes (78% of the total biomass), while, in the river, their share decreased to 9%. The contribution of bacteria was 15% in Dvina Bay and increased to 61% in the river. The importance of algae in the snow was minor: 7% of the total biomass in the marine zone and 30% in the river region. High species diversity of the algal flora in the sandy and sandy-silty littoral grounds was revealed. The values of the total biomass of the bottom algal flora (0.38 g C/m2) were only two to three times lower than the values revealed in similar habitats in the summer. The epipelithic forms (0.15 g C/m2) dominated, being represented by 46 species of algae (49%). The shares of epipsammonic (0.12 g C/m2) and planktonic (0.11 g C/m2) species were almost equal to each other: 25 and 22 species, respectively (27 and 24%).

  2. Biomarker responses and PAH ratios in fish inhabiting an estuarine urban waterway.

    Science.gov (United States)

    Duarte, Rafael Mendonça; Sadauskas-Henrique, Helen; de Almeida-Val, Vera Maria Fonseca; Val, Adalberto Luis; Nice, Helen Elizabeth; Gagnon, Marthe Monique

    2017-10-01

    Many cities worldwide are established adjacent to estuaries and their catchments resulting in estuarine contamination due to intense anthropogenic activities. The aim of this study was to evaluate if fish living in an estuarine urban waterway were affected by contamination, via the measurement of a suite of biomarkers of fish health. Black bream (Acanthopagrus butcheri) were sampled in a small urban embayment and a suite of biomarkers of fish health measured. These were condition factor (CF), liver somatic index (LSI), gonadosomatic index (GSI), hepatic EROD activity, polycyclic aromatic hydrocarbon (PAH) biliary metabolites, serum sorbitol dehydrogenase (s-SDH) and branchial enzymes cytochrome C oxidase (CCO), and lactate dehydrogenase (LDH) activities. The biomarkers of exposure EROD activity, and pyrene- and B(a)P-type biliary metabolites confirmed current or recent exposure of the fish and that fish were metabolizing contaminants. Relative to a reference site, LSI was higher in fish collected in the urban inlet as was the metabolic enzyme LDH activity. CF, GSI, s-SDH, CCO, and naphthalene-type metabolites were at similar levels in the urban inlet relative to the reference site. PAH biliary metabolite ratios of high-molecular-weight to low-molecular-weight suggest that fish from the urban inlet were exposed to pyrogenic PAHs, likely from legacy contamination and road runoff entering the embayment. Similarly, the sediment PAH ratios and the freshness indices suggested legacy contamination of a pyrogenic source, likely originating from the adjacent historic gasworks site and a degree of contamination of petrogenic nature entering the inlet via storm water discharge. Biomarkers of exposure and effect confirmed that black bream collected in the Claisebrook Cove inlet, Western Australia, are currently exposed to contamination and are experiencing metabolic perturbations not observed in fish collected at a nearby reference site. © 2017 Wiley Periodicals, Inc.

  3. Abiotic water quality control on mangrove distribution in estuarine ...

    African Journals Online (AJOL)

    Abiotic water quality control on mangrove distribution in estuarine river channels assessed by a novel boat-mounted electromagnetic- induction technique. Melissa A .... of operation depends on coil orientation, spacing and operation. * To whom all .... the visual estimation method in proportion (%) to the total site area ...

  4. Zoonotic Cryptosporidium Species in Animals Inhabiting Sydney Water Catchments.

    Science.gov (United States)

    Zahedi, Alireza; Monis, Paul; Aucote, Sarah; King, Brendon; Paparini, Andrea; Jian, Fuchun; Yang, Rongchang; Oskam, Charlotte; Ball, Andrew; Robertson, Ian; Ryan, Una

    2016-01-01

    Cryptosporidium is one of the most common zoonotic waterborne parasitic diseases worldwide and represents a major public health concern of water utilities in developed nations. As animals in catchments can shed human-infectious Cryptosporidium oocysts, determining the potential role of animals in dissemination of zoonotic Cryptosporidium to drinking water sources is crucial. In the present study, a total of 952 animal faecal samples from four dominant species (kangaroos, rabbits, cattle and sheep) inhabiting Sydney's drinking water catchments were screened for the presence of Cryptosporidium using a quantitative PCR (qPCR) and positives sequenced at multiple loci. Cryptosporidium species were detected in 3.6% (21/576) of kangaroos, 7.0% (10/142) of cattle, 2.3% (3/128) of sheep and 13.2% (14/106) of rabbit samples screened. Sequence analysis of a region of the 18S rRNA locus identified C. macropodum and C. hominis in 4 and 17 isolates from kangaroos respectively, C. hominis and C. parvum in 6 and 4 isolates respectively each from cattle, C. ubiquitum in 3 isolates from sheep and C. cuniculus in 14 isolates from rabbits. All the Cryptosporidium species identified were zoonotic species with the exception of C. macropodum. Subtyping using the 5' half of gp60 identified C. hominis IbA10G2 (n = 12) and IdA15G1 (n = 2) in kangaroo faecal samples; C. hominis IbA10G2 (n = 4) and C. parvum IIaA18G3R1 (n = 4) in cattle faecal samples, C. ubiquitum subtype XIIa (n = 1) in sheep and C. cuniculus VbA23 (n = 9) in rabbits. Additional analysis of a subset of samples using primers targeting conserved regions of the MIC1 gene and the 3' end of gp60 suggests that the C. hominis detected in these animals represent substantial variants that failed to amplify as expected. The significance of this finding requires further investigation but might be reflective of the ability of this C. hominis variant to infect animals. The finding of zoonotic Cryptosporidium species in these animals may

  5. Zoonotic Cryptosporidium Species in Animals Inhabiting Sydney Water Catchments.

    Directory of Open Access Journals (Sweden)

    Alireza Zahedi

    Full Text Available Cryptosporidium is one of the most common zoonotic waterborne parasitic diseases worldwide and represents a major public health concern of water utilities in developed nations. As animals in catchments can shed human-infectious Cryptosporidium oocysts, determining the potential role of animals in dissemination of zoonotic Cryptosporidium to drinking water sources is crucial. In the present study, a total of 952 animal faecal samples from four dominant species (kangaroos, rabbits, cattle and sheep inhabiting Sydney's drinking water catchments were screened for the presence of Cryptosporidium using a quantitative PCR (qPCR and positives sequenced at multiple loci. Cryptosporidium species were detected in 3.6% (21/576 of kangaroos, 7.0% (10/142 of cattle, 2.3% (3/128 of sheep and 13.2% (14/106 of rabbit samples screened. Sequence analysis of a region of the 18S rRNA locus identified C. macropodum and C. hominis in 4 and 17 isolates from kangaroos respectively, C. hominis and C. parvum in 6 and 4 isolates respectively each from cattle, C. ubiquitum in 3 isolates from sheep and C. cuniculus in 14 isolates from rabbits. All the Cryptosporidium species identified were zoonotic species with the exception of C. macropodum. Subtyping using the 5' half of gp60 identified C. hominis IbA10G2 (n = 12 and IdA15G1 (n = 2 in kangaroo faecal samples; C. hominis IbA10G2 (n = 4 and C. parvum IIaA18G3R1 (n = 4 in cattle faecal samples, C. ubiquitum subtype XIIa (n = 1 in sheep and C. cuniculus VbA23 (n = 9 in rabbits. Additional analysis of a subset of samples using primers targeting conserved regions of the MIC1 gene and the 3' end of gp60 suggests that the C. hominis detected in these animals represent substantial variants that failed to amplify as expected. The significance of this finding requires further investigation but might be reflective of the ability of this C. hominis variant to infect animals. The finding of zoonotic Cryptosporidium species in these

  6. Relating watershed nutrient loads to satellite derived estuarine water quality

    Science.gov (United States)

    Lehrter, J. C.; Le, C.

    2015-12-01

    Nutrient enhanced phytoplankton production is a cause of degraded estuarine water quality. Yet, relationships between watershed nutrient loads and the spatial and temporal scales of phytoplankton blooms and subsequent water quality impairments remain unquantified for most systems. This is partially due to a lack of observations. In many systems, satellite remote sensing of water quality variables may be used to supplement limited field observations and improve understanding of linkages to nutrients. Here, we present the results from a field and satellite ocean color study that quantitatively links nutrients to variations in estuarine water quality endpoints. The study was conducted in Pensacola Bay, Florida, an estuary in the northern Gulf of Mexico that is impacted by watershed nutrients. We developed new empirical band ratio algorithms to retrieve phytoplankton biomass as chlorophyll a (chla), colored dissolved organic matter (CDOM), and suspended particulate matter (SPM) from the MEdium Resolution Imaging Spectrometer (MERIS). MERIS had suitable spatial resolution (300-m) for the scale of Pensacola Bay (area = 370 km2, mean depth = 3.4 m) and a spectral band centered at wavelength 709 nm that was used to minimize the effect of organic matter on chla retrieval. The algorithms were applied to daily MERIS remote sensing reflectance (level 2) data acquired from 2003 to 2011 to calculate nine-year time-series of mean monthly chla, CDOM, and SPM concentrations. The MERIS derived time-series were then analyzed for statistical relations with time-series of mean monthly river discharge and river loads of nitrogen, phosphorus, dissolved organic carbon, and SPM. Regression analyses revealed significant relationships between river loads and MERIS water quality variables. The simple regression models provide quantitative predictions about how much chla, CDOM, and SPM concentrations in Pensacola Bay will increase with increased river loading, which is necessary information

  7. A survey of Vibrio cholerae O1 and O139 in estuarine waters and ...

    African Journals Online (AJOL)

    This study determined whether the estuarine and freshwater environment in Beira, Mozambique, serves as a reservoir of Vibrio cholerae O1 and O139. Ninety-nine estuarine water samples were collected at 6 sites in Beira. An additional 54 samples were collected from rural areas around Beira which included 3 freshwater ...

  8. Toxic pressure of herbicides on microalgae in Dutch estuarine and coastal waters

    NARCIS (Netherlands)

    Booij, P.; Sjollema, S.B.; van der Geest, H.G.; Leonards, P.E.G.; Lamoree, M.H.; de Voogt, P.; Admiraal, W.; Laane, R.W.P.M.; Vethaak, A.D.

    2015-01-01

    For several decades now, there has been an increase in the sources and types of chemicals in estuarine and coastal waters as a consequence of anthropogenic activities. This has led to considerable concern about the effects of these chemicals on the marine food chain. The fact is that estuarine and

  9. Utilization of cyclohexanol by bacteria in a tropical estuarine water.

    Science.gov (United States)

    Ilori, M O

    1999-01-01

    The Lagos lagoon is a wide expanse of estuarine water. The range of temperature, pH and conductivity of samples collected from 3 sources were 27-30 degrees C, 7.8-8.3 and 2.34-2.85 mS respectively. Consistent increase and decrease in the population of indigenous bacteria occurred in the test and control experiments respectively. Organisms in samples from Apapa and Iddo utilized cyclohexanol better than those in the sample from the University of Lagos. The cyclohexanol degrading bacteria were identified as species of Pseudomonas. Acinetobacter, Vibrio, Micrococcus and Flavobacterium. Pseudomonas sp. had the highest growth potential on cyclohexanol. These organisms play important roles in reducing the pollutant loads of the Lagos lagoon.

  10. Suspended solids moderate the degradation and sorption of waste water-derived pharmaceuticals in estuarine waters.

    Science.gov (United States)

    Aminot, Yann; Fuster, Laura; Pardon, Patrick; Le Menach, Karyn; Budzinski, Hélène

    2018-01-15

    This study focuses on the fate of pharmaceuticals discharged into an estuarine environment, particularly into the Turbidity Maximum Zone (TMZ). Batch experiments were set up to investigate the factors regulating the degradation of 53 selected pharmaceuticals. Treated effluents from Bordeaux city (France) were mixed with water from the estuarine Garonne River during 4weeks under 6 characterized conditions in order to assess the influence of suspended particulates, sterilization, untreated wastewater input and dilution on the degradation kinetics. Of the 53 pharmaceuticals monitored, 43 were quantified at the initial time. Only 7 exhibited a persistent behavior (e.g. carbamazepine, meprobamate) while biotic degradation was shown to be the main attenuation process for 38 molecules (e.g. abacavir, ibuprofen highly degradable). Degradation was significantly enhanced by increasing concentrations of suspended solids. A persistence index based on the half-lives of the compounds has been calculated for each of the 43 pharmaceuticals to provide a practical estimate of their relative stability. The stability of pharmaceuticals in estuarine environments is likely to be highly variable and attenuated primarily by changes in suspended solid concentration. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Methicillin-Resistant Bacteria Inhabiting Surface Waters Monitored by mecA-Targeted Oligonucleotide Probes.

    Science.gov (United States)

    Seyedmonir, Elnaz; Yilmaz, Fadime; Icgen, Bulent

    2016-08-01

    Part of a 20-60 kb staphylococcal chromosome cassette called mecA encodes low-affinity penicillin-binding protein PBP2a and causes methicillin resistance. Among all methicillin-resistant bacteria, methicillin-resistant Staphylococcus aureus is a major pathogen and main concern worldwide. Although the origin of the mecA is not very well-defined, mecA homologues are also ubiquitous in methicillin-resistant non-staphylococcal bacteria. Due to the dissemination of methicillin resistance through the transmission of mecA gene among staphylococcal and non-staphylococcal bacteria inhabiting surface waters, there is a need to monitor mecA gene in these waters for public health safety. Therefore, this study aimed at monitoring mecA harboring bacteria inhabiting surface waters by using fluorescently labelled mecA-targeted oligonucleotide probes. Under the hybridization conditions of 55 % formamide and 0.020 M NaCl at 46°C, the oligonucleotide probe used in the study showed high hybridization stringency to the mecA gene targeted. The strong linear relationships observed between the signal intensity and the target gene were used to assess the population dynamics of mecA harboring isolates over a 2-year-period. The results indicated that mecA-targeted oligonucleotide probes can be effectively used for in situ monitoring of methicillin resistant isolates inhabiting surface waters.

  12. Urban Estuarine Beaches and Urban Water Cycle Seepage: The Influence of Temporal Scales

    Directory of Open Access Journals (Sweden)

    Sérgia Costa-Dias

    2018-02-01

    Full Text Available Temperate estuarine beaches are an asset to coastal cities. Being located within the transition zone where the river meets the sea can provide several environmental benefits such as warm water temperature during the summer, flat waters, protection from coastal upwelling-induced morning fog, as well as additional recreational and cultural values. In this study we address a major question—can the urban water cycle impair the water quality dynamics during a bathing season in a temperate Atlantic estuary (Douro, Northwest Portugal? Water quality was assessed according to the EU legal criteria at different time scales. No daily, weekly, or monthly patterns for microbiological descriptors were found, which rather followed the hourly tidal dynamics. Quality decreased during high tide, affecting potentially 800+ beach-users during mid-summer weekends (4 m2 per person. Low water quality was transported upstream from highly populated urban areas. Therefore, the understanding of the dynamics of estuarine systems is essential to adapt the standard official approach, and the obtained results can be used to draw policy recommendations to improve the sampling strategy, aiming for more accurate assessment of the water quality to reduce the risk hazard of estuarine beaches.

  13. Pigment specific in vivo light absorption of phytoplankton from estuarine, coastal and oceanic waters

    DEFF Research Database (Denmark)

    Stæhr, A.; Markager, S.; Sand-Jensen, K.

    2004-01-01

    The influence of phytoplankton photoacclimation and adaptation to natural growth conditions on the chlorophyll a-specific in vivo absorption coefficient (a* ph) was evaluated for samples collected in estuarine, coastal and oceanic waters. Despite an overall gradient in the physio......-chemical environment from estuaries, over coastal, to oceanic waters, no clear relationships were found between a* ph and the prevailing light, temperature, salinity and nutrient concentrations, indicating that short-term cellular acclimation was of minor importance for the observed variability in a* ph. The clear...... decline in a* ph from oceanic, over coastal, to estuarine waters was, however, strongly correlated with an increase in cell size and intracellular chlorophyll a (chl a) content of the phytoplankton, and a reduction of photosynthetic carotenoids relative to chl a. Variations in photoprotective carotenoids...

  14. ESTIMATION OF INHERENT OPTICAL PROPERTIES AND THE WATER QUALITY COMPONENTS IN THE NEUSE RIVER-PAMLICO SOUND ESTUARINE SYSTEM

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    Field observations carried out in the Neuse River-Pamlico Sound Estuarine System (NRE-PS), North Carolina, USA were used to develop optical algorithms for assessing inherent optical properties, IOPs (absorption and backscattering) associated with water quality components (WQC).

  15. Some analytic diagnostic models for transport processes in estuarine and coastal waters

    International Nuclear Information System (INIS)

    Suarez Antola, R.

    2001-03-01

    Advection and dispersion processes in estuarine and coastal waters are briefly reviewed. Beginning from the basic macroscopic equations of transport for a substance diluted or suspended in the considered body of water,several levels of filtering in time and space are described and applied to obtain suitable diagnostic mathematical models both with scale effects and gaussian.The solutions of the aforementioned models,for initial distributions and boundary conditions with enough symmetry,are discussed, as well as their applications to a parameter characterization of the transport properties of the receiving body of water

  16. Numerical modeling of oil spills in continental and estuarine waters

    International Nuclear Information System (INIS)

    Goeury, C.

    2012-10-01

    The application of the European Water Framework Directive on water quality for human consumption and industrial activities creates a need for water quality assessment and monitoring systems. The MIGR'HYCAR research project (http://www.migrhycar.com) was initiated to provide decisional tools for risks connected to oil spills in continental waters (rivers, lakes and estuaries), which represent more than 50% of accidental spills in France. Within the framework of this project, a new numerical oil spill model has been developed, as part of the TELEMAC hydro-informatics system (http://www.opentelemac.org), by combining Lagrangian and Eulerian methods. The Lagrangian model describes the transport of an oil spill near the free surface. The oil spill model enables to simulate the main processes driving oil plumes: advection, diffusion, oil beaching, oil re-floating, evaporation, dissolution, spreading and volatilization. Though generally considered as a minor process, dissolution is important from the point of view of toxicity. To model dissolved oil in water, an Eulerian advection-diffusion model is used. The fraction of dissolved oil is represented by a passive tracer. This approach is able to follow dissolved hydrocarbons in the water column. Laboratory experiments were conducted to characterise the numerous kinetics of the processes listed above. In addition, meso-scale dynamic experiments in artificial channels and test cases derived from the literature are used to validate the numerical model. (author)

  17. Bacterial growth efficiency in the tropical estuarine and coastal waters of Goa, southwest coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Ram, A.; Nair, S.; Chandramohan, D.

    that affect or regulate them? To answer the above ques tions, a series of experiments were conducted with both estuarine and coastal waters using short incubation peri ods [4, 36], In this paper we report for the first time the growth efficiencies...M and 0.62 IlM, respectively. The minimum and maximum phosphate levels in the es· tuarine waters were from 0.85 to 1.58 J.lM. The ammonium concentration ranged from 0.08 to 4.21 IlM. In general, the nutrient concentration was comparatively higher...

  18. Decision aiding handbooks for managing contaminated food production systems, drinking water and inhabited areas in Europe

    DEFF Research Database (Denmark)

    Nisbet, A.F.; Brown, J.; Howard, B.J.

    2010-01-01

    government departments and agencies, emergency services, radiation protection experts, the agriculture and food production sectors, industry and others who may be affected. The handbooks include management options for application in the different phases of an incident. Sources of contamination considered......Three handbooks have been developed, in conjunction with a wide range of stakeholders to assist in the management of contaminated food production systems, inhabited areas and drinking water following a radiological incident. The handbooks are aimed at national and local authorities, central...... non-crisis conditions, to engage stakeholders and to develop local and regional plans. The handbooks can also be applied as part of the decision-aiding process to develop a recovery strategy following an incident. In addition, the handbooks are useful for training purposes and during emergency...

  19. Abiotic water quality control on mangrove distribution in estuarine ...

    African Journals Online (AJOL)

    Due to climate change impacts and the resulting sea-level rise, saline waters have been found further inland in tropical riverine estuaries such as the Godineau ... Red mangrove (Rhizophora mangle) was found in areas with little oxygen, high salinities and high acidity, making it more adaptable to conditions resulting from ...

  20. Variability in estuarine water temperature gradients and influence on ...

    African Journals Online (AJOL)

    Structure and variability of water temperature gradients and potential influence on distribution of two tropical zooplankters (the mysid Mesopodopsis africana and the copepod Acartia natalensis) and their temperate congenerics (M. wooldridgei and A. longipatella) was investigated over a 10-year period in the Mgazi Estuary, ...

  1. Toxic pressure of herbicides on microalgae in Dutch estuarine and coastal waters

    Science.gov (United States)

    Booij, Petra; Sjollema, Sascha B.; van der Geest, Harm G.; Leonards, Pim E. G.; Lamoree, Marja H.; de Voogt, W. Pim; Admiraal, Wim; Laane, Remi W. P. M.; Vethaak, A. Dick

    2015-08-01

    For several decades now, there has been an increase in the sources and types of chemicals in estuarine and coastal waters as a consequence of anthropogenic activities. This has led to considerable concern about the effects of these chemicals on the marine food chain. The fact is that estuarine and coastal waters are the most productive ecosystems with high primary production by microalgae. The toxic pressure of specific phytotoxic chemicals now poses a major threat to these ecosystems. In a previous study, six herbicides (atrazine, diuron, irgarol, isoproturon, terbutryn and terbutylazine) were identified as the main contaminants affecting photosynthesis in marine microalgae. The purpose of this study is to investigate the toxic pressure of these herbicides in the Dutch estuarine and coastal waters in relation to the effective photosystem II efficiency (ΦPSII) in microalgae. Temporal and spatial variations in the concentrations of these herbicides were analyzed based on monitoring data. Additionally, a field study was carried out in which chemical analysis of water was performed and also a toxicity assessment using the Pulse Amplitude Modulation (PAM) fluorometry assay that measures ΦPSII. The toxic pressure on ΦPSII in microalgae has decreased with 55-82% from 2003 to 2012, with the Western Scheldt estuary showing the highest toxic pressure. By combining toxicity data from the PAM assay with chemical analysis of herbicide concentrations, we have identified diuron and terbutylazine as the main contributors to the toxic pressure on microalgae. Although direct effects are not expected, the toxic pressure is close to the 10% effect level in the PAM assay. A compliance check with the current environmental legislation of the European Union revealed that the quality standards are not sufficient to protect marine microalgae.

  2. Distribution of tritium in estuarine waters: the role of organic matter

    International Nuclear Information System (INIS)

    Turner, Andrew; Millward, Geoffrey E.; Stemp, Martin

    2009-01-01

    Tritium is an important environmental radionuclide whose reactivity with ligands and solids in aquatic systems is assumed to be limited. We studied the fractionation and sorption of tritium (added as tritiated water) in river water and seawater, and found that its distribution appears to be influenced by its affinity for organic matter. Tritium rapidly equilibrates with dissolved organic ligands that are retained by a reverse-phase C18 column, and with suspended sediment particles. Significantly, a measurable fraction of sorbed tritium associates with proteinaceous material that is potentially available to sediment-feeding organisms. These characteristics have not been reported previously and cannot be accounted for solely by isotopic exchange with hydrogen. Nevertheless, they are in qualitative agreement with available measurements of tritium in estuarine and coastal waters where its principal discharge is as tritiated water. Further research into the estuarine biogeochemical behaviour of tritium is required and radiological distribution coefficients and concentration factors that are assumed for this radionuclide may require reconsideration.

  3. Degradation of organophosphorus pesticides and their transformation products in estuarine waters

    International Nuclear Information System (INIS)

    Lacorte, S.; Lartiges, S.B.; Garrigues, P.; Barcelo, D.

    1995-01-01

    The degradation of 10 organophosphorus pesticides in natural estuarine waters was studied. Estuarine water samples were spiked with organophosphorus pesticides at 50 μg/L level and were placed into 2-L Pyrexflasks being exposed outdoor to ambient sunlight and temperature. A sample of 10-75 mL of water was collected every week for analysis during a period of 5-6 weeks from January to March. The analytical determinations were performed by solid-phase extraction (SPE) with C 18 Emporedisks followed by GC-NPD and GC-MS with EI and by on-line SPE using PLRP-s exchangeable cartridges (Prospekt) followed by LC-DAD and LC-thermospray MS in PI mode. Five organophosphorus pesticides were stable for less than 1 week (disulfoton, fenamiphos, fenthion, malathion, and temephos), others had a half-life of ca. 1 week (chlorpyrifos-methyl, methidathion, and diazinon), and the rest showed a half-life of ca. 10 days (isofenphos and pyridafenthion). The half-life of three pesticidetransformation products: disulfoton sulfoxide, disulfoton sulfone, and fenthion sulfoxide varied from 7 to 12 days

  4. Seasonal Variability of Mesozooplankton Feeding Rates on Phytoplankton in Subtropical Coastal and Estuarine Waters

    Directory of Open Access Journals (Sweden)

    Mianrun Chen

    2017-06-01

    Full Text Available In order to understand how mesozooplankton assemblages influenced phytoplankton in coastal and estuarine waters, we carried out a monthly investigation on mesozooplankton composition at two contrasting stations of Hong Kong coastal and estuarine waters and simultaneously conducted bottle incubation feeding experiments. The assemblage of mesozooplankton was omnivorous at both stations with varying carnivory degree (the degree of feeding preference of protozoa and animal food to phytoplankton and the variations of carnivory degree were significantly associated with microzooplankton biomass (ciliates for the coastal station, both ciliates and dinoflagellates for the estuarine stations and physical environmental parameters (primarily salinity. High carnivory was primarily due to high composition of noctilucales, Corycaeus spp., Oithona spp. and Acartia spp. Results of feeding experiments showed that grazing impacts on phytoplankton ranged from −5.9 to 17.7%, while the mean impacts were just <4% at both stations. The impacts were size-dependent, by which mesozooplankton consumed around 9% of large-sized phytoplankton while indirectly caused an increase of 4% of small-sized phytoplankton. Mesozooplankton clearance rate on phytoplankton, calculated from the log response of chlorophyll a concentrations by the introduction of bulk grazers after 1-day incubation, was significantly reduced by increasing carnivory degree of the mesozooplankton assemblage. The mechanism for the reduction of mesozooplankton clearance rate with increasing carnivory degree was primarily due to less efficient of filtering feeding and stronger trophic cascades due to suppression of microzooplankton. The feeding rates of mesozooplankton on microzooplankton were not obtained in this study, but the trophic cascades indirectly induced by mesozooplankton carnivorous feeding can be observed by the negative clearance rate on small-sized phytoplankton. Overall, the main significance of

  5. VIS - A database on the distribution of fishes in inland and estuarine waters in Flanders, Belgium.

    Science.gov (United States)

    Brosens, Dimitri; Breine, Jan; Van Thuyne, Gerlinde; Belpaire, Claude; Desmet, Peter; Verreycken, Hugo

    2015-01-01

    The Research Institute for Nature and Forest (INBO) has been performing standardized fish stock assessments in Flanders, Belgium. This Flemish Fish Monitoring Network aims to assess fish populations in public waters at regular time intervals in both inland waters and estuaries. This monitoring was set up in support of the Water Framework Directive, the Habitat Directive, the Eel Regulation, the Red List of fishes, fish stock management, biodiversity research, and to assess the colonization and spreading of non-native fish species. The collected data are consolidated in the Fish Information System or VIS. From VIS, the occurrence data are now published at the INBO IPT as two datasets: 'VIS - Fishes in inland waters in Flanders, Belgium' and 'VIS - Fishes in estuarine waters in Flanders, Belgium'. Together these datasets represent a complete overview of the distribution and abundance of fish species pertaining in Flanders from late 1992 to the end of 2012. This data paper discusses both datasets together, as both have a similar methodology and structure. The inland waters dataset contains over 350,000 fish observations, sampled between 1992 and 2012 from over 2,000 locations in inland rivers, streams, canals, and enclosed waters in Flanders. The dataset includes 64 fish species, as well as a number of non-target species (mainly crustaceans). The estuarine waters dataset contains over 44,000 fish observations, sampled between 1995 and 2012 from almost 50 locations in the estuaries of the rivers Yser and Scheldt ("Zeeschelde"), including two sampling sites in the Netherlands. The dataset includes 69 fish species and a number of non-target crustacean species. To foster broad and collaborative use, the data are dedicated to the public domain under a Creative Commons Zero waiver and reference the INBO norms for data use.

  6. Particulate organic matter in the coastal and estuarine waters of Goa and its relationship with phytoplankton production

    Digital Repository Service at National Institute of Oceanography (India)

    Verlecar, X.N.; Qasim, S.Z.

    . The mean values of chlorophyll and primary productivity were 1.94 mg m-3 and 938.1 mg Cm-2 day-1 in the coastal waters and 4.3 mg m-3 and 636.5 mg Cm-1 day-1 in estuarine waters, respectively. POC/chl ratios were low in June and October even when POC values...

  7. The application of a Biopollution Index in German Baltic estuarine and lagoon waters

    Directory of Open Access Journals (Sweden)

    Anne K. J. Wittfoth

    2013-01-01

    Full Text Available This paper assesses the status of three German Baltic estuarine and lagoon waters with respect to invasive species (macrozoobenthos andtheir impact. A Biological Pollution Index was applied and evaluated. Overall 130 macrozoobenthic species were identified, 17 of whichwere aquatic alien species. The Szczecin Lagoon had the highest number of invasive species (13. Most species were of Pontocaspian origin;inland waterways are likely to play a significant role in their migration. According to the Biological Pollution Index Level (BPL this lagoonwas ‘moderately influenced’ by invasive species. Warnow Estuary had 11 invasive species; their origin noted generally from North-America,suggesting shipping traffic as the major distribution vector; invasive species had the same BPL as in the Szczecin Lagoon. In theDarß-Zingst-Bodden-Chain only 6 invasive species were observed, having the highest relative abundance (9–71%. Furthermore, this areahad the highest BPL of all three areas, i.e. a strong negative impact. The BPL required a lot of data (including historical and some ratingswere subjective and comparisons with other areas assessed were difficult and often impossible. Due to these limitations, it is suggested thatthe BPL should only be used with restrictions as a universal assessment tool for invasive species in the estuarine and lagoon waters of theBaltic Sea.

  8. Comparison of the Seasonal Variations of Synechococcus Assemblage Structures in Estuarine Waters and Coastal Waters of Hong Kong

    Science.gov (United States)

    Xia, Xiaomin; Vidyarathna, Nayani K.; Palenik, Brian; Lee, Puiyin

    2015-01-01

    Seasonal variation in the phylogenetic composition of Synechococcus assemblages in estuarine and coastal waters of Hong Kong was examined through pyrosequencing of the rpoC1 gene. Sixteen samples were collected in 2009 from two stations representing estuarine and ocean-influenced coastal waters, respectively. Synechococcus abundance in coastal waters gradually increased from 3.6 × 103 cells ml−1 in March, reaching a peak value of 5.7 × 105 cells ml−1 in July, and then gradually decreased to 9.3 × 103 cells ml−1 in December. The changes in Synechococcus abundance in estuarine waters followed a pattern similar to that in coastal waters, whereas its composition shifted from being dominated by phycoerythrin-rich (PE-type) strains in winter to phycocyanin-only (PC-type) strains in summer owing to the increase in freshwater discharge from the Pearl River and higher water temperature. The high abundance of PC-type Synechococcus was composed of subcluster 5.2 marine Synechococcus, freshwater Synechococcus (F-PC), and Cyanobium. The Synechococcus assemblage in the coastal waters, on the other hand, was dominated by marine PE-type Synechococcus, with subcluster 5.1 clades II and VI as the major lineages from April to September, when the summer monsoon prevailed. Besides these two clades, clade III cooccurred with clade V at relatively high abundance in summer. During winter, the Synechococcus assemblage compositions at the two sites were similar and were dominated by subcluster 5.1 clades II and IX and an undescribed clade (represented by Synechococcus sp. strain miyav). Clade IX Synechococcus was a relatively ubiquitous PE-type Synechococcus found at both sites, and our study demonstrates that some strains of the clade have the ability to deal with large variation of salinity in subtropical estuarine environments. Our study suggests that changes in seawater temperature and salinity caused by the seasonal variation of monsoonal forcing are two major determinants of

  9. Phytoplankton blooms in estuarine and coastal waters: Seasonal patterns and key species

    Science.gov (United States)

    Carstensen, Jacob; Klais, Riina; Cloern, James E.

    2015-01-01

    Phytoplankton blooms are dynamic phenomena of great importance to the functioning of estuarine and coastal ecosystems. We analysed a unique (large) collection of phytoplankton monitoring data covering 86 coastal sites distributed over eight regions in North America and Europe, with the aim of investigating common patterns in the seasonal timing and species composition of the blooms. The spring bloom was the most common seasonal pattern across all regions, typically occurring early (February–March) at lower latitudes and later (April–May) at higher latitudes. Bloom frequency, defined as the probability of unusually high biomass, ranged from 5 to 35% between sites and followed no consistent patterns across gradients of latitude, temperature, salinity, water depth, stratification, tidal amplitude or nutrient concentrations. Blooms were mostly dominated by a single species, typically diatoms (58% of the blooms) and dinoflagellates (19%). Diatom-dominated spring blooms were a common feature in most systems, although dinoflagellate spring blooms were also observed in the Baltic Sea. Blooms dominated by chlorophytes and cyanobacteria were only common in low salinity waters and occurred mostly at higher temperatures. Key bloom species across the eight regions included the diatoms Cerataulina pelagica and Dactyliosolen fragilissimus and dinoflagellates Heterocapsa triquetra and Prorocentrum cordatum. Other frequent bloom-forming taxa were diatom genera Chaetoceros, Coscinodiscus, Skeletonema, and Thalassiosira. Our meta-analysis shows that these 86 estuarine-coastal sites function as diatom-producing systems, the timing of that production varies widely, and that bloom frequency is not associated with environmental factors measured in monitoring programs. We end with a perspective on the limitations of conclusions derived from meta-analyses of phytoplankton time series, and the grand challenges remaining to understand the wide range of bloom patterns and

  10. Zooplankton variability and copepod assemblage in the coastal and estuarine waters of Goa along the central-west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Achuthankutty, C.T.; Ramaiah, Neelam; Padmavati, G.

    and some typical coastal water taxa rare in the estuary. Copepods were predominant in both areas, but the coastal water population comprised 45 species against 28 species in the estuary. The estuarine copepod population dwindles during the low salinity...

  11. Seasonal dynamics of the genus: Planktoniella Schutt in the estuarine waters of Indian Sundarbans.

    Science.gov (United States)

    Sekh, Sanoyaz; Biswas, Biswajit; Mandal, Manjushree; Sarkar, Neera Sen

    2016-01-01

    The study highlights the dynamics and morphological characteristics of the Genus Planktoniella Schutt. The two available species P. sol (Wallich) Schutt. and P. blanda (Schmidt) Syvertsen and Hasle are important components of the phytoplankton assemblage in the estuarine system of Indian Sundarbans and also marine systems elsewhere. The sampling sites for the purpose of this study include four different spots along a riverine stretch in the estuarine region adjacent to the Tiger Reserve in the Indian Sundarbans flowing into the Bay of Bengal. Integrated phytoplankton samples were preserved for the purpose from composite water samples from each site. The water samples were analysed in field for determining pH, temperature, salinity, conductivity, TDS, turbidity and DO and subsequent to treatment and processing, the samples were microscopically analysed in the laboratory. Significant negative correlation of cell count of both species found with respect to temperature and turbidity. P. sol versus temperature (significant at α = 0.01, p = 0.001) and P. blanda versus temperature (significant at α = 0.05, p = 0.037); P. sol versus turbidity (at α = 0.05, p = 0.019) and P. blanda versus turbidity (at α = 0.05, p = 0.019). Significant positive correlation found with respect to DO and as correlation between the two species themselves. A model has been generated for each of the two species with temperature, turbidity and DO as predictor variables and the two species of Planktoniella as response variables. The influence of other dominant phytoplankton in the samples has also been considered with Pearson correlation computed for each set of species.

  12. Reproductive status of western mosquitofish inhabiting selenium- contaminated waters in the Grassland Water District, Merced County, California

    Science.gov (United States)

    Saiki, M.K.; Martin, B.A.; May, T.W.

    2004-01-01

    This study was implemented to determine if western mosquitofish (Gambusia affinis) populations in the Grassland Water District suffer from impaired reproduction because of seleniferous inflows of agricultural drainwater from the Grassland Bypass Project. During June to July 2001, laboratory trials with pregnant female fish collected from two seleniferous treatment sites exposed to selenium-laden drainwater and two nonseleniferous reference sites yielded fry that averaged >96% survival at birth. In addition, none of the newborn fry exhibited evidence of teratogenesis, a typical consequence of selenium toxicity. Chemical analysis of postpartum female fish and their newborn fry indicated that mosquitofish from seleniferous sites accumulated relatively high body burdens of selenium (3.96 to 17.5 μg selenium/g in postpartum female fish and 5.35 to 29.2 μg selenium/g in their fry), whereas those from nonseleniferous sites contained lower body burdens (0.40 to 2.72 μg selenium/g in postpartum female fish and 0.61 to 4.68 μg selenium/g in their fry). Collectively, these results strongly suggest that mosquitofish inhabiting selenium-contaminated waters are not experiencing adverse reproductive effects at current levels of selenium exposure.

  13. Reproductive status of western mosquitofish inhabiting selenium-contaminated waters in the Grassland water district, Merced county, California.

    Science.gov (United States)

    Saiki, M K; Martin, B A; May, T W

    2004-10-01

    This study was implemented to determine if western mosquitofish (Gambusia affinis) populations in the Grassland Water District suffer from impaired reproduction because of seleniferous inflows of agricultural drainwater from the Grassland Bypass Project. During June to July 2001, laboratory trials with pregnant female fish collected from two seleniferous treatment sites exposed to selenium-laden drainwater and two nonseleniferous reference sites yielded fry that averaged > 96% survival at birth. In addition, none of the newborn fry exhibited evidence of teratogenesis, a typical consequence of selenium toxicity. Chemical analysis of postpartum female fish and their newborn fry indicated that mosquitofish from seleniferous sites accumulated relatively high body burdens of selenium (3.96 to 17.5 microg selenium/g in postpartum female fish and 5.35 to 29.2 microg selenium/g in their fry), whereas those from nonseleniferous sites contained lower body burdens (0.40 to 2.72 microg selenium/g in postpartum female fish and 0.61 to 4.68 microg selenium/g in their fry). Collectively, these results strongly suggest that mosquitofish inhabiting selenium-contaminated waters are not experiencing adverse reproductive effects at current levels of selenium exposure. Copyright 2004 Springer Science + Business Media, Inc.

  14. Preliminary Evidence for the Amplification of Global Warming in Shallow, Intertidal Estuarine Waters.

    Science.gov (United States)

    Oczkowski, Autumn; McKinney, Richard; Ayvazian, Suzanne; Hanson, Alana; Wigand, Cathleen; Markham, Erin

    2015-01-01

    Over the past 50 years, mean annual water temperature in northeastern U.S. estuaries has increased by approximately 1.2°C, with most of the warming recorded in the winter and early spring. A recent survey and synthesis of data from four locations in Southern Rhode Island has led us to hypothesize that this warming may be amplified in the shallow (<1 m), nearshore portions of these estuaries. While intertidal areas are not typically selected as locations for long-term monitoring, we compiled data from published literature, theses, and reports that suggest that enhanced warming may be occurring, perhaps at rates three times higher than deeper estuarine waters. Warmer spring waters may be one of the factors influencing biota residing in intertidal regions both in general as well as at our specific sites. We observed greater abundance of fish, and size of Menidia sp., in recent (2010-2012) seine surveys compared to similar collections in 1962. While any linkages are speculative and data are preliminary, taken together they suggest that shallow intertidal portions of estuaries may be important places to look for the effects of climate change.

  15. Preliminary Evidence for the Amplification of Global Warming in Shallow, Intertidal Estuarine Waters.

    Directory of Open Access Journals (Sweden)

    Autumn Oczkowski

    Full Text Available Over the past 50 years, mean annual water temperature in northeastern U.S. estuaries has increased by approximately 1.2°C, with most of the warming recorded in the winter and early spring. A recent survey and synthesis of data from four locations in Southern Rhode Island has led us to hypothesize that this warming may be amplified in the shallow (<1 m, nearshore portions of these estuaries. While intertidal areas are not typically selected as locations for long-term monitoring, we compiled data from published literature, theses, and reports that suggest that enhanced warming may be occurring, perhaps at rates three times higher than deeper estuarine waters. Warmer spring waters may be one of the factors influencing biota residing in intertidal regions both in general as well as at our specific sites. We observed greater abundance of fish, and size of Menidia sp., in recent (2010-2012 seine surveys compared to similar collections in 1962. While any linkages are speculative and data are preliminary, taken together they suggest that shallow intertidal portions of estuaries may be important places to look for the effects of climate change.

  16. Water quality data collected by the the National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP), 1996 - 1998 (NODC Accession 0000789)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP) collected water quality data in 22 reserves in the United States and...

  17. Water quality, meteorological, and nutrient data collected by the the National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP), 1994 - 2005 (NODC Accession 0019215)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP) collected water quality, meteorological, and nutrient data in 25...

  18. Development and application of a shipboard method for spectrophotometric determination of trace dissolved manganese in estuarine and coastal waters

    Science.gov (United States)

    Feng, Sichao; Huang, Yongming; Yuan, Dongxing; Zhu, Yong; Zhou, Tingjin

    2015-01-01

    A shipboard method for the determination of trace dissolved manganese in estuarine and coastal waters was developed using a technique of reverse flow injection analysis, which adopted a 1-m liquid waveguide capillary cell and spectrophotometric detection of manganese derivation with 1-(2-pyridylazo)-2-naphthol (PAN). The design of dual-sample-carrier speeded up the sample throughput and eliminated the Schlieren effect. The salinity of estuarine and coastal waters caused a huge increase in the blank absorption value at the maximum absorption wavelength; therefore, a less sensitive detection wavelength was selected to achieve a low blank value while the method sensitivity was not significantly decreased. Method parameters were optimized. The salinity effect from estuarine and coastal waters was carefully investigated, and interference from iron was evaluated. The proposed method had high sensitivity with a detection limit of 3.0 nmol L-1 and a wide linear range of 10-1500 nmol L-1 for dissolved manganese in seawater (S=35). The analytical results of five water samples with different salinities obtained using the proposed method showed good agreement with those using a reference ICP-MS method. The sample throughput of the proposed method was 120 h-1, which was capable of obtaining high spatial and temporal resolution data in shipboard analysis. The proposed method had the advantages of convenient application in estuarine and coastal waters with different salinities, low detection limit, as well as high sample throughput. The proposed method was successfully applied to a 24 h on-line analysis and a shipboard underway analysis of dissolved manganese in the Jiulongjiang Estuary.

  19. Biofouling Growth in Cold Estuarine Waters and Evaluation of Some Chitosan and Copper Anti-Fouling Paints

    OpenAIRE

    Pelletier, ?milien; Bonnet, Claudie; Lemarchand, Karine

    2009-01-01

    Ecological concerns about antifouling paints containing non-green tin and copper compounds have highlighted the need for environmentally friendly alternatives. We report here a field test conducted in estuarine waters over two months designed to evaluate the efficiency of a number of active natural and man-made chemical ingredients added into a silicon-polyurethane marine paint. Early steps of biofouling in cold seawater of the St. Lawrence Estuary (Canada) were observed. Analyses, including ...

  20. Multi-reflection photometric flow cell for use in flow injection analysis of estuarine waters

    International Nuclear Information System (INIS)

    Ellis, Peter S.; Lyddy-Meaney, Amanda J.; Worsfold, Paul J.; McKelvie, Ian D.

    2003-01-01

    A multi-reflection flow cell suitable for flow analysis is described. Light from an LED is directed through an optical fibre into a silver coated capillary through a sidewall aperture, and emerges through a similar aperture 10 mm along the capillary after undergoing an estimated 19 reflections. This process provides a sensitivity enhancement of approximately 2.5 compared with a conventional z-cell of the same nominal path length. This enhancement is due to both the increased optical path length achieved by multiple reflection of the light beam through the sample, and minimization of physical dispersion by the use of a short, small internal diameter capillary as the flow cell. The optical design of this flow cell also minimizes the Schlieren effect. Optical and hydrodynamic characteristics of this multi-reflection cell have been evaluated using a series of bromothymol blue dye studies. Application of the flow cell to the determination of reactive phosphorus in estuarine waters with wide variation in salinity and refractive index is also described

  1. Distinct Aeromonas Populations in Water Column and Associated with Copepods from Estuarine Environment (Seine, France

    Directory of Open Access Journals (Sweden)

    Gautier Chaix

    2017-07-01

    Full Text Available Aeromonas spp. are ubiquitous bacteria primarily recovered from aquatic ecosystems. They are found in fresh water as well as estuarine and marine waters, and in association with numerous autochthonous aquatic organisms in these environments. However, aeromonads are also etiologic agents of fish diseases and are now recognized as emerging pathogens in humans. The estuary is therefore a key environment, harboring autochthonous aeromonads, and aeromonads originating from humans and animals, mainly released by treated WWTP effluent or watershed run-off via tributaries. The present study compares the abundance and the diversity of Aeromonas populations. Over 2 years of monitoring (eight campaigns from February 2013 to November 2015, the occurrence of Aeromonas was investigated within the water column (water and fluid mud and in association with copepods. Moreover, the diversity of Aeromonas populations was ascertained by analyzing gyrB and radA sequences, and the antibiotic-resistance phenotypes were determined using the disk diffusion method. This study shows, for the first time, the presence of Aeromonas spp. in water (1.1 × 102 to 1.2 ± 0.3 × 103 CFU.100 mL-1, fluid mud (2.6 ± 2.6 × 102 to 9.8 ± 0.9 × 103 CFU.g-1 and in association with living copepods (1.9 ± 0.7 × 102 to >1.1 × 104 CFU.g-1 in the Seine estuary. Moreover, the diversity study, conducted on 36 strains isolated from the water column and 47 strains isolated from copepods, indicates distinct populations within these two compartments. Strains distributed in five clusters corresponding to A. bestiarum (n = 6; 5.45%, A. encheleia (n = 1; 0.91%, A. media (n = 22; 20.0%, A. rivipollensis (n = 34; 30.91% and A. salmonicida (n = 47; 42.73%. A. salmonicida is the most abundant species associated with Eurytemora affinis (n = 35; 74.47%. In contrast, A. salmonicida accounts for only 30.56% (n = 11 of isolates in the water column. This study shows the coexistence of distinct populations

  2. North Inlet-Winyah Bay National Estuarine Research Reserve's (NERR) Estuarine Water Quality Data for the North Inlet and Winyah Bay Estuaries, Georgetown, South Carolina: 1993-2002

    Data.gov (United States)

    Baruch Institute for Marine and Coastal Sciences, Univ of South Carolina — The North Inlet Estuary and the adjacent lower northeastern section of the Winyah Bay Estuary were designated as part of the National Estuarine Research Reserve...

  3. Bioaccumulation of selected metals in bivalves (Unionidae) and Phragmites australis inhabiting a municipal water reservoir

    OpenAIRE

    Rzymski, Piotr; Niedzielski, Przemysław; Klimaszyk, Piotr; Poniedziałek, Barbara

    2014-01-01

    Urbanization can considerably affect water reservoirs by, inter alia, input, and accumulation of contaminants including metals. Located in the course of River Cybina, Maltański Reservoir (Western Poland) is an artificial shallow water body built for recreation and sport purposes which undergoes restoration treatment (drainage) every 4 years. In the present study, we demonstrate an accumulation of nine metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) in water, sediment, three bivalve species (Anodo...

  4. Influence of dissolved organic matter on particle-water interactions of Co, Cu and Cd under estuarine conditions

    Science.gov (United States)

    Takata, Hyoe; Aono, Tatsuo; Tagami, Keiko; Uchida, Shigeo

    2012-10-01

    Influence of dissolved organic matter (DOM) on particle-water interactions of trace metals (Co, Cu, and Cd) between particulate (>0.2 μm) and dissolved (≤0.2 μm) phases has been investigated along a salinity gradient using samples from the estuarine area of northern Sagami Bay, Japan. Partitioning experiments were performed by mixing riverine suspended particles with the mixtures of different proportions of river and marine end-members and determining concentrations of Co, Cu and Cd in particulate and dissolved phases. Concentrations and distribution coefficients (Kds) between particulate and dissolved phases of Co and Cu were dependent on the presence of DOM. The Kds of Co and Cu in the mixtures in the presence of DOM were lower than those in mixtures that had been ultraviolet-irradiated (UV-irradiated) (absence of DOM), throughout the salinity gradient. In addition, speciation calculations estimated that a greater fraction of Co and Cu in the dissolved phase was present in organic form throughout the salinity gradient, while the seawater ion concentrations and ligand competition (e.g., competition from Ca and Mg and formation of stable and soluble chloro-, sulphato-, and carbonato complexes) had a small effect on the speciation of Co. These results indicate that DOM may play an important role in controlling the speciation and the particle-water interactions of Co and Cu in the estuarine waters. As for Cd, the effect of DOM on the interactions of this metal was less intense than for Co and Cu. Seawater ions appeared to act as an important variable for controlling the particle-water interactions of Cd in the estuarine waters.

  5. Estimation of settling velocity of sediment particles in estuarine and coastal waters

    Science.gov (United States)

    Nasiha, Hussain J.; Shanmugam, Palanisamy

    2018-04-01

    A model for estimating the settling velocity of sediment particles (spherical and non-spherical) in estuarine and coastal waters is developed and validated using experimental data. The model combines the physical, optical and hydrodynamic properties of the particles and medium to estimate the sediment settling velocity. The well-known Stokes law is broadened to account for the influencing factors of settling velocity such as particle size, shape and density. To derive the model parameters, laboratory experiments were conducted using natural flaky seashells, spherical beach sands and ball-milled seashell powders. Spectral light backscattering measurements of settling particles in a water tank were made showing a distinct optical feature with a peak shifting from 470-490 nm to 500-520 nm for particle populations from spherical to flaky grains. This significant optical feature was used as a proxy to make a shape determination in the present model. Other parameters experimentally determined included specific gravity (ΔSG) , Corey shape factor (CSF) , median grain diameter (D50) , drag coefficient (Cd) and Reynolds number (Re) . The CSF values considered ranged from 0.2 for flaky to 1.0 for perfectly spherical grains and Reynolds numbers from 2.0 to 105 for the laminar to turbulent flow regimes. The specific gravity of submerged particles was optically derived and used along with these parameters to estimate the sediment settling velocity. Comparison with the experiment data showed that the present model estimated settling velocities of spherical and non-spherical particles that were closely consistent with the measured values. Findings revealed that for a given D50, the flaky particles caused a greater decrease in settling velocity than the spherical particles which suggests that the particle shape factor has a profound role in influencing the sediment settling velocity and drag coefficients, especially in transitional and turbulent flow regimes. The present model can

  6. Reproductive biology of the tarpon snook Centropomus pectinatus (Perciformes, Centropomidae) in estuarine waters in the south-western Atlantic.

    Science.gov (United States)

    Freitas, M O; Abilhoa, V

    2017-08-01

    The reproductive biology of Centropomus pectinatus is described from an artisanal fish landings collaborative monitoring programme between May 2012 and April 2013 in estuarine waters in north-eastern Brazil. The total length (L T ) at which 50% are mature was 24 cm, corresponding to 37·7% of the maximum recorded L T . Gonado-somatic indices were variable, but highest values were in June and August 2012. Length-frequency distributions showed male dominance in smaller length classes (15-30 cm) and females in larger length classes (>30 cm). © 2017 The Fisheries Society of the British Isles.

  7. Salicylic acid determination in estuarine and riverine waters using hollow fiber liquid-phase microextraction and capillary zone electrophoresis.

    Science.gov (United States)

    da Silva, Gilmar Silvério; Lima, Diana L D; Esteves, Valdemar Inocêncio

    2017-06-01

    A low-cost methodology using hollow fiber liquid-phase microextraction (HF-LPME) and capillary zone electrophoresis (CZE) with UV-Vis detector was developed to analyze the salicylic acid (SA) in estuarine and riverine waters. The technique is easy-to-use and rapid, and demands little volume of organic solvent. The extraction was carried out using a polypropylene membrane supporting into octan-1-ol. HF-LPME under optimized conditions (donor solution sample pH 2, acceptor solution pH 14, sample volume 25 mL, fiber length 10 cm, acceptor volume 25 μL, extraction time 3 h and stirring speed 350 rpm) presented high enrichment factor (407 times) and good recovery in real water samples (from 88 to 110%). A limit of detection of 2.6 μg L -1 was achieved using CZE with UV-Vis detector as quantification method. The method was applied to direct quantification of SA in environmental complex estuarine and riverine water matrices.

  8. VIS – A database on the distribution of fishes in inland and estuarine waters in Flanders, Belgium

    Directory of Open Access Journals (Sweden)

    Dimitri Brosens

    2015-01-01

    Full Text Available The Research Institute for Nature and Forest (INBO has been performing standardized fish stock assessments in Flanders, Belgium. This Flemish Fish Monitoring Network aims to assess fish populations in public waters at regular time intervals in both inland waters and estuaries. This monitoring was set up in support of the Water Framework Directive, the Habitat Directive, the Eel Regulation, the Red List of fishes, fish stock management, biodiversity research, and to assess the colonization and spreading of non-native fish species. The collected data are consolidated in the Fish Information System or VIS. From VIS, the occurrence data are now published at the INBO IPT as two datasets: ‘VIS - Fishes in inland waters in Flanders, Belgium’ and ‘VIS - Fishes in estuarine waters in Flanders, Belgium’. Together these datasets represent a complete overview of the distribution and abundance of fish species pertaining in Flanders from late 1992 to the end of 2012. This data paper discusses both datasets together, as both have a similar methodology and structure. The inland waters dataset contains over 350,000 fish observations, sampled between 1992 and 2012 from over 2,000 locations in inland rivers, streams, canals, and enclosed waters in Flanders. The dataset includes 64 fish species, as well as a number of non-target species (mainly crustaceans. The estuarine waters dataset contains over 44,000 fish observations, sampled between 1995 and 2012 from almost 50 locations in the estuaries of the rivers Yser and Scheldt (“Zeeschelde”, including two sampling sites in the Netherlands. The dataset includes 69 fish species and a number of non-target crustacean species. To foster broad and collaborative use, the data are dedicated to the public domain under a Creative Commons Zero waiver and reference the INBO norms for data use.

  9. A parasitological survey of natural water springs and inhabitants of a tourist city in southeastern Brazil.

    Science.gov (United States)

    Branco, Nilson; Leal, Diego Averaldo Guiguet; Franco, Regina Maura Bueno

    2012-05-01

    The goals of this study were to investigate the occurrence of Cryptosporidium oocysts and Giardia cysts in main springs of Campos do Jordão, an important tourist city, in Brazil and to gather the largest amount of parasitological data from autochthonous population that live in rural areas of this city. The membrane filtration technique followed by direct immunofluorescence assay was employed for concentration and visualization of waterborne protozoa. In the period between June 2003 and May 2004, the presence of at least one pathogenic protozoa was detected in 25.0% (3/12) of the springs studied, with mean concentrations ranging from 0.2 to 0.3 Cryptosporidium sp. oocysts and 0.07 to 0.1 Giardia sp. cysts/L. The coproparasitological investigation conducted in dwellers from two rural communities from this city revealed that 49.2% (91/185) of people had intestinal parasites. Among pathogenic protozoa, Cryptosporidium was the most prevalent species (8.1%) followed by Giardia duodenalis (5.9%), Entamoeba histolytica/Entamoeba dispar (2.7%), and Blastocystis hominis (2.2%). The most prevalent geohelminths were Ascaris lumbricoides (14.9%) and Trichuris trichiura (9.7%). This study demonstrated the contamination and the distribution of intestinal parasites, especially Cryptosporidium and Giardia species, in different springs of an important tourist city in Brazil, highlighting the need of monitoring natural water sources. The high prevalence of intestinal parasitosis detected in some specific populations of this city may function as a link of transmission of different intestinal parasitosis due to soil and water contamination, contributing to the maintenance of parasite life cycles. Therefore, the inclusion of consistent public health interventions with measures that include the protection of springs, the installation of minimum health infrastructure, and primary education of the population are widely necessary, aiming the control and prevention of parasite infections.

  10. Arius kesslerl & Sciadeops troschelii (Pisces: Ariidae growth in floating net cages in estuarine waters of Buenventura Bay-Colombia

    Directory of Open Access Journals (Sweden)

    Efraín Alfonso Rubio

    1999-07-01

    Full Text Available Two species of estuary catfish the Arius kessleri (CoCoCo and the Sciadeops troschelii (Nato were held in floating net cages at varying densities in estuarine waters of Buenventura Bay-Colombia. After 120 days for the Cococo had weights of 84.1 g Y64 g with densities of 5 and 30 specimen/rn'. The growth average was 0.58-0.39 g/day; the net yield obtained vary from 0.35 to 1.16 Kg/m', the food conversion ratio vary from 3.3 to 5.0 and de survival rate vary from 86% to 100%. With the Nato we obtained weights of 164 and 184 g, beginning with weights of 41 and 108 g their growth average vary from 0.50 to 0.82 g/day. The net yield obtained vary from 0.58 to 0.75 Kg/m' and the survival rate vary from 83% to 100%. From these results we conclude that the two species of catfish studied are strong species but they do not offer good possibilities for fish farming in estuarine waters.

  11. Hydrocarbons identified in extracts from estuarine water accommodated no. 2 fuel oil by gas chromatography-mass spectrometry

    Science.gov (United States)

    Lewis, B. W.; Walker, A. L.; Bieri, R. H.

    1974-01-01

    Results are presented on a computerized gas chromatograph-mass spectrometer analysis of methylene chloride and n-heptane extracts of a No. 2 fuel oil accommodated estuarine water sample. The analytical method is briefly described, and the limitations on the identifications are categorized. Some attempt was made to determine major and trace constituents in the water accommodate. Altogether 66 hydrocarbon compounds were identified specifically, and 75 compounds were partially identified. Seven compounds could be recognized as major constituents of the water accommodated oil and ten were present only as traces. The aromatic compounds found were alkyl benzenes, naphthalene, tetralin, indane, biphenyl, fluorene, anthracene, and some of their alkyl substituted isomers in the range of carbon numbers C7 to C15. Four n-alkanes, C10 to C13, were found along with four other assorted hydrocarbons.

  12. Impact of Calcium and Magnesium in Groundwater and Drinking Water on the Health of Inhabitants of the Slovak Republic.

    Science.gov (United States)

    Rapant, Stanislav; Cvečková, Veronika; Fajčíková, Katarína; Sedláková, Darina; Stehlíková, Beáta

    2017-03-08

    This work aims to evaluate the impact of the chemical composition of groundwater/drinking water on the health of inhabitants of the Slovak Republic. Primary data consists of 20,339 chemical analyses of groundwater (34 chemical elements and compounds) and data on the health of the Slovak population expressed in the form of health indicators (HI). Fourteen HIs were evaluated including life expectancy, potential years of lost life, relative/standardized mortality for cardiovascular and oncological diseases, and diseases of the gastrointestinal and respiratory systems. The chemical and health data were expressed as the mean values for each of the 2883 Slovak municipalities. Artificial neural network (ANN) was the method used for environmental and health data analysis. The most significant relationship between HI and chemical composition of groundwater was documented as Ca + Mg (mmol·L -1 ), Ca and Mg. The following limit values were set for these most significant groundwater chemical parameters: Ca + Mg 2.9-6.1 mmol·L -1 , Ca 78-155 mg·L -1 and Mg 28-54 mg·L -1 . At these concentration ranges, the health of the Slovak population is the most favorable and the life expectancy is the highest. These limit values are about twice as high in comparison to the current Slovak valid guideline values for drinking water.

  13. Simulation of the fate of faecal bacteria in estuarine and coastal waters based on a fractionated sediment transport model

    Science.gov (United States)

    Yang, Chen; Liu, Ying

    2017-08-01

    A two-dimensional depth-integrated numerical model is refined in this paper to simulate the hydrodynamics, graded sediment transport process and the fate of faecal bacteria in estuarine and coastal waters. The sediment mixture is divided into several fractions according to the grain size. A bed evolution model is adopted to simulate the processes of the bed elevation change and sediment grain size sorting. The faecal bacteria transport equation includes enhanced source and sink terms to represent bacterial kinetic transformation and disappearance or reappearance due to sediment deposition or re-suspension. A novel partition ratio and dynamic decay rates of faecal bacteria are adopted in the numerical model. The model has been applied to the turbid water environment in the Bristol Channel and Severn estuary, UK. The predictions by the present model are compared with field data and those by non-fractionated model.

  14. Biofouling growth in cold estuarine waters and evaluation of some chitosan and copper anti-fouling paints.

    Science.gov (United States)

    Pelletier, Emilien; Bonnet, Claudie; Lemarchand, Karine

    2009-07-14

    Ecological concerns about antifouling paints containing non-green tin and copper compounds have highlighted the need for environmentally friendly alternatives. We report here a field test conducted in estuarine waters over two months designed to evaluate the efficiency of a number of active natural and man-made chemical ingredients added into a silicon-polyurethane marine paint. Early steps of biofouling in cold seawater of the St. Lawrence Estuary (Canada) were observed. Analyses, including dry biomass, flow cytometry and spectrofluorimetry, demonstrated a short-term antibacterial action of chitosan-based paints although no significant anti-algal action was observed. Cuprous oxide paints were efficient against bacteria and algae invasion in the first two weeks, especially those with added organic biocides such as isothiazolone and copper pyrithione. However, the overall dry biomass and chlorophyll a content were similar for all chitosan-and copper-based paints after 63 days. Microscopic observations revealed variation in the highly diverse benthic diatom population including species Navicula, Melosira, Cocconeis, Nitshzcia, Fragilaria and Amphora. Results suggest no real long-term efficiency for tested antifouling paints and highlight a particular need for green antifouling ingredients that are active under northern estuarine conditions.

  15. Biofouling Growth in Cold Estuarine Waters and Evaluation of Some Chitosan and Copper Anti-Fouling Paints

    Directory of Open Access Journals (Sweden)

    Karine Lemarchand

    2009-07-01

    Full Text Available Ecological concerns about antifouling paints containing non-green tin and copper compounds have highlighted the need for environmentally friendly alternatives. We report here a field test conducted in estuarine waters over two months designed to evaluate the efficiency of a number of active natural and man-made chemical ingredients added into a silicon-polyurethane marine paint. Early steps of biofouling in cold seawater of the St. Lawrence Estuary (Canada were observed. Analyses, including dry biomass, flow cytometry and spectrofluorimetry, demonstrated a short-term antibacterial action of chitosan-based paints although no significant anti-algal action was observed. Cuprous oxide paints were efficient against bacteria and algae invasion in the first two weeks, especially those with added organic biocides such as isothiazolone and copper pyrithione. However, the overall dry biomass and chlorophyll a content were similar for all chitosan- and copper-based paints after 63 days. Microscopic observations revealed variation in the highly diverse benthic diatom population including species Navicula, Melosira, Cocconeis, Nitshzcia, Fragilaria and Amphora. Results suggest no real long-term efficiency for tested antifouling paints and highlight a particular need for green antifouling ingredients that are active under northern estuarine conditions.

  16. An inversion of the estuarine circulation by sluice water discharge and its impact on suspended sediment transport

    Science.gov (United States)

    Schulz, Kirstin; Gerkema, Theo

    2018-01-01

    The Wadden Sea is characterized by a complex topography of branching channels and intertidal flats, in which the interplay between fresh water discharges, wind forcing and the tidal current causes sediment transport rates and direction to be highly variable in space and time. During three field campaigns, indications of a negative estuarine circulation have been found in a channel adjacent to the coast in the Western Dutch Wadden Sea. Contrary to the classical picture of estuarine circulation, a periodic density stratification was observed that builds up during flood and breaks down during ebb. This can be related to a large freshwater source at the mouth of the channel, the sluice in Kornwerderzand. In this study, observations of this phenomenon are presented, and with the help of a numerical model the different drivers for residual suspended matter transport in this area, namely tidal asymmetries in the current velocity and the above mentioned periodic stratification, are investigated. It is found that the residual current in the area of interest points in ebb direction, caused by both the elongated ebb flow phase and the periodic stratification. On the contrary, the stronger flood currents cause a transport of suspended matter in flood direction. This transport is counteracted and therefore diminished by the effects of the sluice discharge.

  17. Water relations of coastal and estuarine Rhizophora mangle: xylem pressure potential and dynamics of embolism formation and repair.

    Science.gov (United States)

    Melcher, P J; Goldstein, G; Meinzer, F C; Yount, D E; Jones, T J; Holbrook, N M; Huang, C X

    2001-01-01

    Physiological traits related to water transport were studied in Rhizophora mangle (red mangrove) growing in coastal and estuarine sites in Hawaii. The magnitude of xylem pressure potential (P x ), the vulnerability of xylem to cavitation, the frequency of embolized vessels in situ, and the capacity of R. mangle to repair embolized vessels were evaluated with conventional and recently developed techniques. The osmotic potential of the interstitial soil water (π sw ) surrounding the roots of R. mangle was c. -2.6±5.52×10 -3 and -0.4±6.13×10 -3  MPa in the coastal and estuarine sites, respectively. Midday covered (non-transpiring) leaf water potentials (Ψ L ) determined with a pressure chamber were 0.6-0.8 MPa more positive than those of exposed, freely-transpiring leaves, and osmotic potential of the xylem sap (π x ) ranged from -0.1 to -0.3 MPa. Consequently, estimated midday values of P x (calculated by subtracting π x from covered Ψ L ) were about 1 MPa more positive than Ψ L determined on freely transpiring leaves. The differences in Ψ L between covered and transpiring leaves were linearly related to the transpiration rates. The slope of this relationship was steeper for the coastal site, suggesting that the hydraulic resistance was larger in leaves of coastal R. mangle plants. This was confirmed by both hydraulic conductivity measurements on stem segments and high-pressure flowmeter studies made on excised leafy twigs. Based on two independent criteria, loss of hydraulic conductivity and proportions of gas- and liquid-filled vessels in cryo-scanning electron microscope (cryo-SEM) images, the xylem of R. mangle plants growing at the estuarine site was found to be more vulnerable to cavitation than that of plants growing at the coastal site. However, the cryo-SEM analyses suggested that cavitation occurred more readily in intact plants than in excised branches that were air-dried in the laboratory. Cryo-SEM analyses also revealed that, in both sites

  18. Simultaneous determination of twelve trace elements in estuarine and sea water using pre-irradiation chromatography

    International Nuclear Information System (INIS)

    Greenberg, R.R.; Kingston, H.M.

    1982-01-01

    A procedure is described for the preconcentration of 100 m of estuarine and seawater into a solid sample using Chelex-100 resin. This solid sample weighs less than half a gram and contains the transition metals and many other elements of interest, but is essentially free from the alkali metals, the alkaline earth metals, and the halogens. The concentrations of Co, Cr, Cu, Fe, Mn, Mo, Ni, Sc, Th, U, V and Zn have been determined in seawater when this procedure was coupled to neutron activation analysis. (author)

  19. Serological responses to Cryptosporidium antigens in inhabitants of Hungary using conventionally filtered surface water and riverbank filtered drinking water.

    Science.gov (United States)

    Farkas, K; Plutzer, J; Moltchanova, E; Török, A; Varró, M J; Domokos, K; Frost, F; Hunter, P R

    2015-10-01

    In this study the putative protective seroprevalence (PPS) of IgG antibodies to the 27-kDa and 15/17-kDa Cryptosporidium antigens in sera of healthy participants who were and were not exposed to Cryptosporidium oocysts via surface water-derived drinking water was compared. The participants completed a questionnaire regarding risk factors that have been shown to be associated with infection. The PPS was significantly greater (49-61%) in settlements where the drinking water originated from surface water, than in the control city where riverbank filtration was used (21% and 23%). Logistic regression analysis on the risk factors showed an association between bathing/swimming in outdoor pools and antibody responses to the 15/17-kDa antigen complex. Hence the elevated responses were most likely due to the use of contaminated water. Results indicate that waterborne Cryptosporidium infections occur more frequently than reported but may derive from multiple sources.

  20. Assessment of natural radium isotopes and 222Rn in water samples from Cananeia-Iguape estuarine complex, Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Oliveira, Joselene de; Jesus, Sueli Carvalho de; Abrahao, Fernanda Franco; Santos, Glorivania Ferreira dos; Braga, Elisabete de Santis; Chiozzini, Vitor

    2009-01-01

    Radium isotopes and radon are among the most important natural radionuclides in the environment from both radioprotection and geo-hydrological points of view. These radionuclides are a powerful tool for studying coastal processes and have been used intensively as tracers of groundwater sources that discharge into the ocean. In this paper, naturally occurring radium isotopes and 222 Rn were determined to trace water exchange and SGD in Cananeia-Iguape estuarine complex, a shallow coastal plain estuary in southern Sao Paulo area. The research work was carried out during the first semester of 2009 and covered stations located both in Cananeia and Iguape outlets, as well as samples collected in Ribeira of Iguape River and groundwater. Activity concentrations of 226 Ra in estuarine waters from Cananeia outlet varied from 2.9 mBq L -1 to 4.7 mBq L -1 , while 228 Ra concentrations ranged from 22 mBq L -1 to 45 mBq L -1 . In Iguape outlet, activities of 226 Ra ranged from 1.6 mBq L -1 to 6.6 mBq L -1 ; 228 Ra varied from 13 mBq L -1 to 20 mBq L -1 . Activities of Ra were slightly higher in samples collected at 5 m depth than at the surface water level. Groundwater activity concentrations of 226 Ra ranged from 0.63 mBq L -1 to 12 mBq L -1 and for 228 Ra from 18 mBq L -1 to 39 mBq L -1 . In groundwater, the 228 Ra/ 226 Ra activity ratios varied from 3.3 to 31.7. 222 Rn activities in groundwater up to 747 Bq L -1 were observed. Increased nitrate contents were observed in groundwater samples collected in Cananeia and Comprida Island. (author)

  1. Molecular Approach to Microbiological Examination of Water Quality in the Grand Bay National Estuarine Research Reserve (NERR) in Mississippi, USA

    Science.gov (United States)

    Kishinhi, Stephen S.; Tchounwou, Paul B.; Farah, Ibrahim O.

    2013-01-01

    Grand Bay National Estuarine Research Reserve (NERR) is an important ecosystem in the Mississippi Gulf Coast. It serves as important nursery areas for juveniles of many species of fish. The bay is also used for fishing, crabbing, oyster togging, boating as well as recreation. Like in other aquatic environments, this bay may be contaminated by microorganisms including pathogenic bacteria. The objective of this study was to evaluate the microbiological quality of water in the Grand Bay NERR and determine the levels and potential source(s) of human fecal pollution. To achieve this goal, water samples were collected aseptically every month in Bayou Heron, Bayou Cumbest, Point Aux Chenes Bay and Bangs Lake. Enterococci were concentrated from water samples by membrane filtration according to the methodology outlined in USEPA Method 1600. After incubation, DNA was extracted from bacteria colonies on the membrane filters by using QIAamp DNA extraction kit. Water samples were also tested for the presence of traditional indicator bacteria including: heterotrophic plate count, total coliforms, fecal coliforms, and Enterococcus bacteria. The marker esp gene was detected in one site of Bayou Cumbest, an area where human populations reside. Data from this study indicates higher concentrations of indicator bacteria compared to the recommended acceptable levels. Presence of esp marker and high numbers of indicator bacteria suggest a public health concern for shellfish and water contact activities. Hence, control strategies should be developed and implemented to prevent further contamination of the Grand bay NERR waters. PMID:23761974

  2. Parameterization of the chlorophyll a-specific in vivo light absorption coefficient covering estuarine, coastal and oceanic waters

    DEFF Research Database (Denmark)

    Stæhr, P. A.; Markager, S. S.

    2004-01-01

    We evaluated models predicting the spectral chlorophyll-a (Chl a)-specific absorption coefficient (a*ph (¿)) from Chl a concentration [Chl a] on the basis of 465 phytoplankton absorption spectra collected in estuarine, coastal and oceanic waters. A power model on ln-transformed data provided.......015 m2 mg-1 Chl a) at 440 nm, the peak absorption of Chl a in the blue part of the spectrum. The variations in the modelled a*ph spectra were within realistic predictions of a*ph (¿) and the model satisfactorily reproduced the spectral flattening with increasing [Chl a]. The parameterization of a......*ph (¿) confirmed the indirect dependency of a*ph (¿) on [Chl a] through co-variations between [Chl a] with pigment packaging and pigment composition. Although pigment packaging determined the spectral flattening, analysis of absorption ratios revealed a systematic change in pigment composition with profound...

  3. Water-quality trends and basin activities and characteristics for the Albemarle-Pamlico estuarine system, North Carolina and Virginia

    Science.gov (United States)

    Harned, D.A.; Davenport, M.S.

    1990-01-01

    The Albemarle-Pamlico estuarine system has a total basin area of nearly 31,000 square miles and includes the Neuse, Tar, Pamlico, Roanoke, Chowan, and Alligator Rivers, and the Albemarle, Pamlico, Currituck, Croatan, and Roanoke Sounds. Albemarle Sound receives the greatest freshwater inflow of all the sounds in the estuarine system. Inflow to this sound averages about 13,500 cubic feet per second. Inflow to Pamlico Sound from the Pamlico River averages around 5,400 cubic feet per second, and average inflow into the Neuse River estuary is about 6,100 cubic feet per second. Approximately one-half of the inflow into the system is from ground-water discharge. The Neuse River basin has had the greatest increases in wastewater discharges (650 percent since the 1950's) and had the greatesttotal wastewater discharges of any of the basins in the study area, averaging about 200 million gallons per day in 1988. Wastewater discharges into the Neuse and Tar Rivers were nearly equal to the 7-day, 10-year low flows for these rivers. Land-use data compiled in 1973 for the lower parts of the Neuse River basin and lower part of the Tar-Pamlico River basin indicate that 25 percent of the area was evergreen forest, 25 percent was forested wetlands, 20 percent was cropland and pasture, 12 percent was mixed forest, 10 percent was nonforested wetland, and 4 percent was urban. The amount of nonforested wetland in the part of the study area along the Outer Banks declined 6.5 percent from 1973 to 1983. The numbers of farms and acreage in agricultural use in the study area have declined since the 1920's. A decrease of more than 60 percentin the number of farms was shown between the early 1950's and 1982. Fertilizer sales increased through the 1970's, but declined in the 1980's. Manufacturing employment has increased in the last 30 years, while agricultural employment has decreased. Data from seven stations of the U.S. Geological Survey National Stream Quality Accounting Network were used to

  4. Reproductive and health assessment of fathead minnows (Pimephales promelas) inhabiting a pond containing oil sands process-affected water

    Energy Technology Data Exchange (ETDEWEB)

    Kavanagh, Richard J., E-mail: rkavanag@uoguelph.ca [Department of Integrative Biology, University of Guelph, Guelph, ON, Canada N1G 2W1 (Canada); Frank, Richard A.; Solomon, Keith R. [Centre for Toxicology, University of Guelph, Guelph, ON, Canada N1G 2W1 (Canada); Van Der Kraak, Glen [Department of Integrative Biology, University of Guelph, Guelph, ON, Canada N1G 2W1 (Canada)

    2013-04-15

    Highlights: ► Fish were collected from a pond containing oil sands process-affected water (OSPW). ► They were compared to fish from two reference sites within the oil sands region. ► Differences in GSIs and tubercle numbers were observed in fish from the OSPW pond. ► Opercula, gills, and 11-KT concentrations also differed in fish from the OSPW pond. ► Black spot and tapeworms were not observed in any of the fish from the OSPW pond. -- Abstract: Previous laboratory based studies have shown that oil sands process-affected waters (OSPWs) containing high concentrations of naphthenic acids (>25 mg/l) have adverse effects on the reproductive physiology of fish. The purpose of this study was to assess the reproductive development and health of a wild population of fathead minnows (Pimephales promelas) inhabiting an OSPW pond that has moderate concentrations of naphthenic acids (∼10 mg/l). Fathead minnows were collected at various times during the period of 2006 through 2008 from Demonstration Pond (OSPW) located at Syncrude Canada Ltd., and two reference sites, Beaver Creek reservoir and Poplar Creek reservoir, which are all north of Fort McMurray, AB, Canada. Condition factor, gill histopathology, gonadosomatic indices, liver somatic indices, male secondary sexual characteristics, and plasma sex steroids were examined. Depending on the time of year that fathead minnows were collected, there were differences in the condition factor, gonadosomatic indices, liver somatic indices, and secondary sexual characteristics of fathead minnows (in males) from Demonstration Pond when compared to the fathead minnows from the reference sites. In comparison to reference fish, lower concentrations of 11-ketotestosterone were measured in the plasma of male fathead minnows collected from Demonstration Pond in June 2006 and July 2007. Black spot disease and Ligula intestinalis were prevalent in fathead minnows from the reference sites but were not observed in fathead minnows

  5. Tidal time-scale variation in nutrient flux across the sediment water interface of an estuarine tidal flat

    Science.gov (United States)

    Sakamaki, Takashi; Nishimura, Osamu; Sudo, Ruichi

    2006-05-01

    We determined the range of the tidal variations in nutrient flux across the sediment-water interface and elucidated mechanisms of the flux variation in two estuarine intertidal flats (one sand, one mud) in northeastern Japan. Nutrient flux was measured using in situ light and dark chambers, which were incubated for 2 h, 2-6 times per day. Results showed that nutrient concentration in overlying water varied by tide and was also affected by sewage-treated water inflow. The nutrient fluxes responded quickly to the tidal variation in overlying water chemistry and the range of the variation in flux was as large as the seasonal-scale variation reported in previous studies. In the sand flat, salinity increase likely enhanced benthos respiration and led to increases in both O 2 consumption and PO 43- regeneration under low illumination, while benthic microalgae were likely to actively generate O 2, uptake PO 43- and suppress PO 43- release under high illumination (>900 μmol photons m -2 s -1). Also in the mud flat, PO 43- flux was related with O 2 flux, although the range of temporal variation in PO 43- flux was small. In both the flats, NH 4+ flux was always governed by NH 4+ concentration in the overlying water; either an increase in NH 4+ uptake or a decrease in NH 4+ release was observed as the NH 4+ concentration rose due to inflow of river water or input of sewage-treated water. Although NO 3- tended to be released in both tidal flats when low NO 3- concentration seawater dominated, their relationship was likely to be weakened under conditions of low oxygen consumption and suppressed denitrification. It is likely that tidal variation in nutrient flux is governed more by the nutrient concentration than other factors, such as benthic biological processes, particularly in the case where nutrient concentration in the overlying water is relatively high and with wide amplitude.

  6. North Inlet-Winyah Bay National Estuarine Research Reserve’s (NERR) Estuarine Surface Water Nutrient, Suspended Sediment, and Chlorophyll a Data for the North Inlet and Winyah Bay Estuaries, Georgetown, South Carolina: 2002-2004

    Data.gov (United States)

    Baruch Institute for Marine and Coastal Sciences, Univ of South Carolina — National Estuarine Research Reserve System The National Estuarine Research Reserve System was established by the Coastal Zone Management Act of 1972 (as amended) and...

  7. Validation of stir bar sorptive extraction for the determination of 24 priority substances from the European Water Framework Directive in estuarine and sea water.

    Science.gov (United States)

    Huertas, Cristina; Morillo, José; Usero, José; Gracia-Manarillo, Ignacio

    2007-05-15

    This paper describes the validation of a method for the determination of 24 priority substances from the European Framework Directive in estuarine and sea water using the new extraction technique known as stir bar sorptive extraction (SBSE), followed by thermal desorption using capillary gas chromatography-mass spectrometry. We studied linearity, detection and quantitation limits and accuracy (which includes determination of trueness and precision). Using the lack-of-fit method we tested linearity in the 0-200ngL(-1) range for all the priority substances. The detection and quantification limits were less than 5 and 10ngL(-1), respectively, for most of the compounds studied. Precision was assessed by variance analysis (ANOVA) and relative standard values of less than 10% were obtained for repeatability and less than 15% for intermediate precision. The recovery percentages in spiked estuarine and sea water were close to 100%. Finally, for quality control of the method (stability of precision and accuracy through time), we developed a method for calculating Shewhart control charts based on the information obtained in the validation process.

  8. Sup(239,240)Pu in estuarine and shelf waters of the north-eastern United States

    International Nuclear Information System (INIS)

    Sholkovitz, E.R.; Mann, D.R.

    1987-01-01

    The distribution of sup(239,240)Pu between dissolved and particulate forms has been measured in four estuaries on the north-east coast of the United States (Connecticut River, Delaware Bay, Chesapeake Bay, and Mullica River). The data cover the whole salinity range from freshwater input to shelf waters at 3.5% and includes one profile from a nearly anoxic basin in the Chesapeake Bay. In the organic-rich Mullica River estuary, large-scale removal of riverine dissolved sup(239,240)Pu occurs at low salinities due to salt-induced coagulation, a mechanism analogous to that for iron and humic acids. Within the 0 to 2.5-3.5% zone in the other three estuaries, the activity of dissolved sup(239,240)Pu increases almost conservatively. The activities of particulate sup(239,240)Pu are highest in the more turbid waters of low salinity regime (0-1.5%), but become increasingly insignificant with respect to dissolved sup(239,240)Pu as salinities increase. At higher salinities corresponding to shelf water, there is a sharp increase in dissolved sup(239,240)Pu activity. The dissolved sup(239,240)Pu activity within each estuary appears to be inversely related to the flushing time of water. The sharp decrease in dissolved sup(239,240)Pu activities between shelf and estuarine waters appears to be driven by removal within the estuaries themselves rather than on the shelf. Dissolved sup(239,240)Pu activities are lower in the nearly-anoxic bottom waters of Chesapeake Bay indicating enhanced removal by redox transformation of Pu [i.e., Pu(V) to Pu(IV)]. (author)

  9. Water quality, meteorological, and nutrient data collected by the the National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP) from January 1, 1995 to August 1, 2011 (NODC Accession 0052765)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP) collected water quality, meteorological, and nutrient data in 26...

  10. Ecotoxicological water assessment of an estuarine river from the Brazilian Northeast, potentially affected by industrial wastewater discharge.

    Science.gov (United States)

    de Melo Gurgel, Piatã; Navoni, Julio Alejandro; de Morais Ferreira, Douglisnilson; do Amaral, Viviane Souza

    2016-12-01

    Water pollution generated by industrial effluents discharge is a threat to the maintenance of aquatic ecosystems and human development. The Jundiai River estuarine, located in Northeast Brazil, receives an industrial pretreated effluent load from the city of Macaíba/RN/Brazil. The present study aimed to assess the water quality of this water reservoir through i) physicochemical characterization, ii) quantification of metal concentration and iii) by an ecotoxicological assessment carried out using Mysidopsis juniae and Pomacea lineata. The study was performed throughout the period comprising May to September 2014. Physicochemical variables such as chloride, total solids and electrical conductivity presented values in the waste discharge point, significantly different with those located out of the waste releasing point. Apart from that, metal concentration showed variable behavior throughout the monitored period. Levels of Al, Fe, Cu, Cd, Cr, Ni, Pb and Ag were over the considered guidelines. Both natural and anthropogenic sources seem to be involved in the resulting environmental scenario. A reduction in the fecundity rate (using Mysidopsis juniae) along with an increase in mortality rate (in both species) was observed ratifying the presence of toxic substances in this water reservoir. Moreover, a correlation analysis stated an association of the aforementioned toxicological effects with the delivery of industrial waste products. The ecotoxicological assessment performed highlighted the presence of toxic substance/s in water from the Jundiai River. Especially as a consequence of industrial activity, a fact that might threaten the bioma and, therefore, the human health of the population settled in the studied region. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Distribution of nutrients in the coastal and estuarine waters of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Verlecar, X.N.

    remained higher than those in the coastal waters. The relation between salinity and nutrients suggest that the fresh water is the main source for the addition of nitrate to the estuary. Seasonal fluctuation in the primary productivity and chlorophyll a...

  12. Ban on commercial fishing in the estuarine waters of New South Wales, Australia: Community consultation and social impacts

    International Nuclear Information System (INIS)

    Momtaz, Salim; Gladstone, William

    2008-01-01

    In its effort to resolve the conflict between commercial and recreational fishers the New South Wales (NSW) government (NSW Fisheries) banned commercial fishing in the estuarine waters. The NSW Fisheries conducted a number of studies and held meetings with the affected communities including commercial fishers prior to the implementation of the ban. To investigate how community consultation played a role in the decision-making process especially as perceived by the commercial fishers and to determine actual social impacts of the ban on commercial fishers, in-depth interviews were conducted with the commercial fishers. This research reveals that despite the NSW Fisheries' consultations with commercial fishers prior to the closure, the latter were confused about various vital aspects of the decision. It further reveals that, the commercial fishers faced a number of significant changes as a result of this decision. We argue that a better decision-making process and outcome would have been possible through a meaningful consultation with the commercial fishers and a social impact assessment

  13. An in situ postexposure feeding assay with Carcinus maenas for estuarine sediment-overlying water toxicity evaluations

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Susana M. [Instituto de Ciencias Biomedicas de Abel Salazar (ICBAS), Departamento de Estudos de Populacoes, Largo Abel Salazar 2, 4099-003 Porto (Portugal); Centro Interdisciplinar de Investigacao Marinha e Ambiental, Laboratorio de Ecotoxicologia, Rua dos Bragas 289, 4050-123 Porto (Portugal); Moreira-Santos, Matilde [Instituto do Ambiente e Vida, Departamento de Zoologia da Universidade de Coimbra, Largo Marques de Pombal, 3004-517 Coimbra (Portugal); Guilhermino, Lucia [Instituto de Ciencias Biomedicas de Abel Salazar (ICBAS), Departamento de Estudos de Populacoes, Largo Abel Salazar 2, 4099-003 Porto (Portugal); Centro Interdisciplinar de Investigacao Marinha e Ambiental, Laboratorio de Ecotoxicologia, Rua dos Bragas 289, 4050-123 Porto (Portugal); Ribeiro, Rui [Instituto do Ambiente e Vida, Departamento de Zoologia da Universidade de Coimbra, Largo Marques de Pombal, 3004-517 Coimbra (Portugal)]. E-mail: rui.ribeiro@zoo.uc.pt

    2006-01-15

    This study developed and evaluated a short-term sublethal in situ toxicity assay for estuarine sediment-overlying waters, with the crab Carcinus maenas (L.) based on postexposure feeding. It consisted of a 48-h in situ exposure period followed by a short postexposure feeding period (30 min). A precise method for quantifying feeding, using the Polychaeta Hediste (Nereis) diversicolor Mueller as food source, was first developed. The sensitivity of the postexposure feeding response was verified by comparing it to that of lethality, upon cadmium exposure. The influence of environmental conditions prevailing during exposure (salinity, temperature, substrate, light regime, and food availability) on postexposure feeding was also addressed. The potential of this in situ assay was then investigated by deploying organisms at ten sites, located in reference and contaminated Portuguese estuaries. Organism recovery ranged between 90% and 100% and a significant postexposure feeding depression (16.3-72.7%) was observed at all contaminated sites relatively to references. - A new sub-lethal toxicity assay is presented for marine invertebrates.

  14. Differential changes in production measures for an estuarine-resident sparid in deep and shallow waters following increases in hypoxia

    Science.gov (United States)

    Cottingham, Alan; Hall, Norman G.; Hesp, S. Alex; Potter, Ian C.

    2018-03-01

    This study determined how productivity measures for a fish species in different water depths of an estuary changed in response to the increase in hypoxia in deep waters, which had previously been shown to occur between 1993-95 and 2007-11. Annual data on length and age compositions, body mass, growth, abundance, biomass, production and production to biomass ratio (P/B) were thus determined for the estuarine-resident Acanthopagrus butcheri in nearshore shallow (fish typically reside. Annual densities, biomass and production in shallow waters of fish m-2, 2-4 g m-2 and ∼2 g m-2 y-1 in the earlier period were far lower than the 0.1-0.2 fish m-2, 8-15 g m-2 and 5-10 g m-2 y-1 in the later period, whereas the reverse trend occurred in deep waters, with values of 6-9 fish net-1, 2000-3900 g net-1, 900-1700 g net-1 y-1 in the earlier period vs fish net-1, ∼110 g net-1 and 27-45 g net-1 y-1 in the later period. Within the later period, and in contrast to the trends with annual abundance and biomass, the production in shallow waters was least during 2008/09, rather than greatest, reflecting the slow growth in that particularly cool year. The presence of substantial aggregations of both small and large fish in shallow waters accounts for the abundance, biomass and production in those waters increasing between those periods and thus, through a density-dependent effect, provide a basis for the overall reduction in growth. In marked contrast to the trends with the other three production measures, annual production to biomass ratios (P/B) in shallow waters in the two years in the earlier period, and in three of the four years of the later period, fell within the same range, i.e. 0.6-0.9 y-1, but was only 0.2 y-1 in 2008/09, reflecting the poor growth in that year. This emphasises the need to obtain data on P/B for a number of years when considering the implications of the typical P/B for a species in an estuary, in which environmental conditions and the growth of a species

  15. 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.

  16. Local and regional effects of reopening a tidal inlet on estuarine water quality, seagrass habitat, and fish assemblages

    Science.gov (United States)

    Milbrandt, Eric C.; Bartleson, Richard D.; Coen, Loren D.; Rybak, Olexandr; Thompson, Mark A.; DeAngelo, Jacquelyn A.; Stevens, Philip W.

    2012-06-01

    Blind Pass is an inlet that separates Sanibel and Captiva Islands in southwest Florida but has historically closed and opened by both anthropogenic and natural processes. In July 2010, a dredging project to open the small inlet between the two barrier islands was completed. The objective of this study was to use and supplement ongoing estuary-monitoring programs to examine the responses of water quality, seagrass habitat metrics, and fish assemblages both in the immediate vicinity of the inlet and at broader scales (up to 40 km2). As far as we are aware, there are no previous studies with this intensity of sampling, both before and after an inlet opening. Significant increases in salinity and turbidity were observed inside Blind Pass, with significant decreases in CDOM and chlorophyll a, however, the effects were not far-reaching and limited to less than 1.7 km from the inlet within Pine Island Sound. Seagrass habitat metrics were expected to respond rapidly after the inlet was opened given the reduced light attenuation. However, there were no changes in shoot densities, species composition, and epiphytic algae within the approximately one-year duration of the study. The reopening of the pass did not substantially change fish assemblage structure, except for those from deeper habitats. Although immediate increases in the abundances of estuarine-dependent species were predicted in shallow habitats post opening, this did not occur. In conclusion, the effects of reopening a relatively small ocean inlet on water quality were apparent in the immediate vicinity of the inlet (within 1.7 km), but far-reaching effects on water quality, seagrass metrics, and fish assemblages were not immediately apparent in this well-flushed estuary. If subtle changes in tidal exchange and circulation affect productivity of seagrasses or its fish assemblages at broad scales, it may take several years to reach a steady state.

  17. Estuarine Sediment Budgets for Chesapeake Bay Tributaries

    Science.gov (United States)

    2012-09-01

    2003. Estuarine sediment sources: A Summary Report of Sediment Processes in Chesapeake Bay and Watershed . Water-Resources Investigations Report 03...2007. Sources and transport of sediment in the watershed : Synthesis of US Geological Survey science for the Chesapeake Bay ecosystem and...originator. Estuarine Sediment Budgets for Chesapeake Bay Tributaries by Julie D. Herman PURPOSE. This Coastal and Hydraulics Engineering

  18. Assessing the influence of nutrient reduction on water quality using a three-dimensional model: case study in a tidal estuarine system.

    Science.gov (United States)

    Liu, Wen-Cheng; Chan, Wen-Ting

    2014-12-01

    A coupled three-dimensional hydrodynamic and water quality model has been developed and applied to the Danshuei River estuarine system and adjacent coastal sea. The water quality model considers various species of nitrogen, phosphorus, organic carbon, and phytoplankton as well as dissolved oxygen and is driven by a three-dimensional hydrodynamic model. The hydrodynamic and water quality models were validated with observations of water surface elevation, velocity, salinity distribution, and water quality parameters. Statistical error analysis shows that predictions of hydrodynamics, salinity, dissolved oxygen, and nutrients from the model simulation quantitatively agreed with the observed data. The validated model was then applied to predict water quality conditions as a result of a reduction in nutrient loadings based on different engineering strategies. The simulated results revealed that the dissolved oxygen concentration would increase significantly and would be higher than 2 mg/L in the main stream and in three tributaries to meet the minimum statutory requirement for dissolved oxygen. Active estuarine management focused on the reduction of anthropogenic nutrient loads is needed for improvement in water quality.

  19. Environmental study of the waters of Mandovi - Zuari estuarine complex, Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Singbal, S.Y.S.

    variations of some environmental parameters at different stations at surface and bottom waters of complex were studied during 1972-73, 1975 and 1977-78. In general, weak thermal stratification is developed at some stations during monsoon and post...

  20. Observations on biofilm bacteria isolated from aluminium panels immersed in estuarine waters

    Digital Repository Service at National Institute of Oceanography (India)

    Sonak, S.; Bhosle, N.B.

    Microfouling biomass generally increased on aluminium panels immersed in the surface waters of a tropical estuary over a period of 30 d. A hundred bacterial colonies were randomly isolated, purified and morphologically, physiologically...

  1. NUTRIENT CRITERIA TECHNICAL GUIDANCE MANUAL - ESTUARINE AND COASTAL MARINE WATERS, OCTOBER 2001

    Science.gov (United States)

    Nutrient overenrichment is a major cause of water pollution in the United States. The purpose of this manual is to provide scientifically defensible technical guidance to assist States, authorized Tribes, and other governmental entities in developing numeric nutrient criteria fo...

  2. Production and associations of zooplankton in estuarine and nearshore waters of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, V.R.

    Zooplankton production in the Zuari and Mandovi estuaries indicated 2 peaks-one in November and another in March/April. In the nearshore waters very high value of zooplankton biomass was observed in April associated with Trichodesmium bloom. Mean...

  3. Perfluorinated compounds in water, sediment, soil and biota from estuarine and coastal areas of Korea

    Energy Technology Data Exchange (ETDEWEB)

    Naile, Jonathan E. [Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK (Canada); Khim, Jong Seong, E-mail: jongseongkhim@korea.ac.k [Division of Environmental Science and Ecological Engineering, Korea University, Seoul 136-713 (Korea, Republic of); Wang Tieyu; Chen Chunli; Luo Wei [State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Science, Beijing (China); Kwon, Bong-Oh; Park, Jinsoon; Koh, Chul-Hwan [School of Earth and Environmental Sciences (Oceanography), Seoul National University, Seoul (Korea, Republic of); Jones, Paul D. [Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK (Canada); Lu Yonglong [State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Science, Beijing (China); Giesy, John P. [Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK (Canada); Department of Biology and Chemistry, Center for Coastal Pollution and Conservation, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Department of Zoology, Center for Integrative Toxicology, Michigan State University, E. Lansing, MI (United States)

    2010-05-15

    Soil, sediment, water, and biota collected from the western coast of Korea were analyzed to determine occurrence and sources of perfluorinated compounds (PFCs). PFCs were significantly concentrations of PFCs were measured in some water and biological samples, while concentrations of PFCs in soils and sediments were relatively low. The most widely detected compound was found to be perfluorooctanesulfonate (PFOS), with a maximum concentration in water of 450 ng/L and in fish of 612 ng/g, dw. PFOS concentrations in water and biota were both less than those thought to cause toxicity. However, in both cases concentrations were within a factor of 10 of the toxicity threshold concentration. Concentrations of PFCs were significantly greater downstream than those upstream on the same river, suggesting point sources. Overall, the detection of PFCs at relatively great concentrations in various environmental matrixes from this region of Korea suggests that further studies characterizing PFCs and their potential risk to both humans and wildlife are needed. - Among various environmental media measured, water and biological samples showed relatively high degrees of PFC contamination with the existence of point sources mainly upstream of coastal areas in Korea.

  4. Needs Assessment for the Use of NASA Remote Sensing Data in the Development and Implementation of Estuarine and Coastal Water Quality Standards

    Science.gov (United States)

    Spiering, Bruce; Underwood, Lauren; Ellis, Chris; Lehrter, John; Hagy, Jim; Schaeffer, Blake

    2010-01-01

    The goals of the project are to provide information from satellite remote sensing to support numeric nutrient criteria development and to determine data processing methods and data quality requirements to support nutrient criteria development and implementation. The approach is to identify water quality indicators that are used by decision makers to assess water quality and that are related to optical properties of the water; to develop remotely sensed data products based on algorithms relating remote sensing imagery to field-based observations of indicator values; to develop methods to assess estuarine water quality, including trends, spatial and temporal variability, and seasonality; and to develop tools to assist in the development and implementation of estuarine and coastal nutrient criteria. Additional slides present process, criteria development, typical data sources and analyses for criteria process, the power of remote sensing data for the process, examples from Pensacola Bay, spatial and temporal variability, pixel matchups, remote sensing validation, remote sensing in coastal waters, requirements for remotely sensed data products, and needs assessment. An additional presentation examines group engagement and information collection. Topics include needs assessment purpose and objectives, understanding water quality decision making, determining information requirements, and next steps.

  5. A comparative review of recovery processes in rivers, lakes, estuarine and coastal waters

    NARCIS (Netherlands)

    Verdonschot, P.F.M.; Spears, B.M.; Feld, C.K.; Brucet, S.; Keizer-Vlek, H.E.; Borja, A.; Elliot, M.; Kernan, M.; Johnson, R.K.

    2013-01-01

    The European Water Framework Directive aims to improve ecological status within river basins. This requires knowledge of responses of aquatic assemblages to recovery processes that occur after measures have been taken to reduce major stressors. A systematic literature review comparatively assesses

  6. Preliminary Evidence for the Amplification of Global Warming in Shallow, Intertidal Estuarine Waters

    Science.gov (United States)

    Over the past 50 years, mean annual water temperature in northeastern U.S. estuaries has increased by approximately 1.2°C, with most of the warming recorded in the winter and early spring. We hypothesize that this warming may be amplified in the shallow (<2m), nearshore portions ...

  7. Pigment specific in vivo light absorption of phytoplankton from estuarine, coastal and oceanic waters

    DEFF Research Database (Denmark)

    Stæhr, A.; Markager, S.; Sand-Jensen, K.

    2004-01-01

    -chemical environment from estuaries, over coastal, to oceanic waters, no clear relationships were found between a* ph and the prevailing light, temperature, salinity and nutrient concentrations, indicating that short-term cellular acclimation was of minor importance for the observed variability in a* ph. The clear...

  8. Spectral variations of UV-A and PAR solar radiation in estuarine waters of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Talaulikar, M.; Suresh, T.; Silveira, N.; Desa, E.; Matondkar, S.G.P.; Lotlikar, A.

    radiation (400 to 700 nm), PAR and ultraviolet radiation in the range 350-400 nm (UV-A) are presented here. The mean PAR values at the surface were 327 W/m sup(2) and reduced to 84 W/m sup(2) at first optical depth, Z sub(90) (m) in water. The first optical...

  9. Time-scale Dependence of Response of an Estuarine Water Quality Model to Nutrient Loading

    Science.gov (United States)

    We describe calibration and evaluation of a water quality model being implemented for Narragansett Bay to quantify the response of concentrations of nutrients, phytoplankton chlorophyll a and dissolved oxygen in the Bay to loading rates of nutrients and other boundary conditions....

  10. Effects of waves on water dispersion in a semi-enclosed estuarine bay

    Science.gov (United States)

    Delpey, M. T.; Ardhuin, F.; Otheguy, P.

    2012-04-01

    The bay of Saint Jean de Luz - Ciboure is a touristic destination located in the south west of France on the Basque coast. This small bay is 1.5km wide for 1km long. It is semi-enclosed by breakwaters, so that the area is mostly protected from waves except in its eastern part, where wave breaking is regularly observed over a shallow rock shelf. In the rest of the area the currents are generally weak. The bay receives fresh water inflows from two rivers. During intense raining events, the rivers can introduce pollutants in the bay. The input of pollutants combined with the low level dynamic of the area can affect the water quality for several days. To study such a phenomenon, mechanisms of water dispersion in the bay are investigated. The present paper focuses on the effects of waves on bay dynamics. Several field experiments were conducted in the area, combining wave and current measurements from a set of ADCP and ADV, lagrangian difter experiments in the surfzone, salinity and temperature profile measurements. An analysis of this set of various data is provided. It reveals that the bay combines remarkable density stratification due to fresh water inflows and occasionally intense wave-induced currents in the surfzone. These currents have a strong influence on river plume dynamics when the sea state is energetic. Moreover, modifications of hydrodynamics in the bay passes are found to be remarkably correlated with sea state evolutions. This result suggests a significant impact of waves on the bay flushing. To further analyse these phenomena, a three dimensional numerical model of bay hydrodynamics is developed. The model aims at reproducing fresh water inflows combined with wind-, tide- and wave-induced currents and mixing. The model of the bay is implemented using the code MOHID , which has been modified to allow the three dimensional representation of wave-current interactions proposed by Ardhuin et al. [2008b] . The circulation is forced by the wave field modelled

  11. Genomics and ecophysiology of heterotrophic nitrogen fixing bacteria isolated from estuarine surface water

    DEFF Research Database (Denmark)

    Bentzon-Tilia, Mikkel; Severin, Ina; Hansen, Lars H.

    2015-01-01

    heterotrophic organisms are widespread in marine bacterioplankton, but their autecology and ecological significance are unknown. Here, we report genomic and ecophysiology data in relation to N2 fixation by three environmentally relevant heterotrophic bacteria isolated from Baltic Sea surface water: Pseudomonas...... between nitrogenase reductase gene expression and ethylene (C2H4) production indicated tight posttranscriptional-level control. The N2 fixation rates obtained suggested that, given the right conditions, these heterotrophic diazotrophs could contribute significantly to in situ rates. IMP...

  12. Three-phase solvent bar micro-extraction as an approach to silver ultra-traces speciation in estuarine water samples.

    Science.gov (United States)

    López-López, José Antonio; Herce-Sesa, Belén; Moreno, Carlos

    2015-01-01

    Silver ion inputs into the environment due to human activities have been increased in the last years because it has been used as a bactericide with application in medical, homecare and self-care products. In addition, it is toxic at low concentration for aquatic organisms. In estuarine waters, salinity and dissolved organic matter (DOM) regulate Ag(+) concentration by the formation of complexes as AgCln((n-1)-) and Ag-DOM. Difficulties of Ag(+) analysis in estuaries are associated to its low concentration level and interferences of sample matrix. Liquid and solid phase extraction methods have been used for speciation of silver in waters; however, miniaturized methods that offer a better environmental profile are desirable. Hollow fiber liquid phase micro-extraction (HFLPME) allows obtaining higher pre-concentration factors with a reduction of waste generation. Notwithstanding, some operational improvements are needed to permit their use as a routine method that can be afforded using a configuration of three-phase solvent bar micro-extraction (3PSBME). In this work, tri-isobutylphosphine sulphide (TIBPS) has been used as an extractant for Ag(+) pre-concentration in estuarine waters by 3PSBME. Under optimized conditions, Ag(+) has been pre-concentrated 60 times and the method presents a limit of detection of 1.53 ng L(-1). To evaluate which Ag species is transported by TIBPS, Cl(-) and DOM have been added to synthetic samples. As a result, a decrease in Ag pre-concentration efficiency after additions has been observed and quantified. Results showed that Ag(+) is selectively transported by TIBPS from estuarine water samples after comparison of the results with those obtained by the reference method of liquid extraction with APDC/DDDC. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Performance of passive samplers for monitoring estuarine water column concentrations: 2. Emerging contaminants.

    Science.gov (United States)

    Perron, Monique M; Burgess, Robert M; Suuberg, Eric M; Cantwell, Mark G; Pennell, Kelly G

    2013-10-01

    Measuring dissolved concentrations of emerging contaminants, such as polybrominated diphenyl ethers (PBDEs) and triclosan, can be challenging due to their physicochemical properties resulting in low aqueous solubilities and association with particles. Passive sampling methods have been applied to assess dissolved concentrations in water and sediments primarily for legacy contaminants. Although the technology is applicable to some emerging contaminants, the use of passive samplers with emerging contaminants is limited. In the present study, the performance of 3 common passive samplers was evaluated for sampling PBDEs and triclosan. Passive sampling polymers included low-density polyethylene (PE) and polyoxymethylene (POM) sheets, and polydimethylsiloxane (PDMS)-coated solid-phase microextraction (SPME) fibers. Dissolved concentrations were calculated using measured sampler concentrations and laboratory-derived partition coefficients. Dissolved tri-, tetra-, and pentabrominated PBDE congeners were detected at several of the study sites at very low pg/L concentrations using PE and POM. Calculated dissolved water concentrations of triclosan ranged from 1.7 ng/L to 18 ng/L for POM and 8.8 ng/L to 13 ng/L for PE using performance reference compound equilibrium adjustments. Concentrations in SPME were not reported due to lack of detectable chemical in the PDMS polymer deployed. Although both PE and POM were found to effectively accumulate emerging contaminants from the water column, further research is needed to determine their utility as passive sampling devices for emerging contaminants. © 2013 SETAC.

  14. Estuarine and coastal connectivity of an estuarine-dependent fishery ...

    African Journals Online (AJOL)

    This study used acoustic telemetry to assess the usage of multiple estuaries and coastal waters by the estuarine-dependent spotted grunter Pomadasys commersonnii. Twenty-six adult fish were tagged with acoustic transmitters in the Kariega and Bushmans estuaries, South Africa, and their movements along a 300-km ...

  15. Genomics and ecophysiology of heterotrophic nitrogen fixing bacteria isolated from estuarine surface water

    DEFF Research Database (Denmark)

    Bentzon-Tilia, Mikkel; Severin, Ina; Hansen, Lars H.

    2015-01-01

    heterotrophic organisms are widespread in marine bacterioplankton, but their autecology and ecological significance are unknown. Here, we report genomic and ecophysiology data in relation to N2 fixation by three environmentally relevant heterotrophic bacteria isolated from Baltic Sea surface water: Pseudomonas...... in length and complexity between isolates. All three isolates could sustain growth by N2 fixation in the absence of reactive N, and this fixation was stimulated by low concentrations of oxygen in all three organisms (≈4 to 40 μmol O2 liter-1). P. stutzeri BAL361 did, however, fix N at up to 165 μmol O2...... between nitrogenase reductase gene expression and ethylene (C2H4) production indicated tight posttranscriptional-level control. The N2 fixation rates obtained suggested that, given the right conditions, these heterotrophic diazotrophs could contribute significantly to in situ rates. IMP...

  16. Suitability of seven species of soil-inhabiting invertebrates for testing toxicity of pesticides in soil pore water

    NARCIS (Netherlands)

    Ronday, R.; Houx, N.W.H.

    1996-01-01

    This study assessed the suitability of seven species of soil invertebrates for toxicologically testing pesticides in water. Requirements were that the organisms must survive in water, be easy to handle, be easy to breed, be sensitive to pesticides, and show unambiguous toxicological effects. The

  17. Monsoon-induced changes in the size-fractionated phytoplankton biomass and production rate in the estuarine and coastal waters of southwest coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Madhu, N.V.; Jyothibabu, R.; Balachandran, K.K.

        Author version: Environ. Monit. Assess., vol.166(1-4); 2010; 521-528 Monsoon induced changes in the size fractionated phytoplankton biomass and production rate in the estuarine and coastal waters of southwest coast of India Madhu. N. V, Jyothibabu.... R, Balachandran. K. K National Institute of Oceanography, Regional Centre, Kochi -18, India Abstract Changes in the autotrophic pico- (0.2-2µm), nano- (2-20µm) and micro- (>20µm) plankton biomass (chlorophyll a) and primary production were...

  18. Evaluation of the radius-226 doses incorporated with the consumption waters, which is receive by the City of Havana inhabitants

    International Nuclear Information System (INIS)

    Tomas Zerquera, J.; Prendes Alonso, M.; Fernandez Gomez, I.M.; Martinez Ricardo, N.

    2001-01-01

    Because of the relatively good solubility of radium compounds contained in the crust of the earths, frequently is this possible to find in spring waters concentration of radium 226 which may be significant. Taking in account that person consumer important volumes of waters annually, it is necessary to assess the dose to population due to the intake of radium 226 by this pathway. Samples were taking in the principal water sources in Havana City and for each samples the radium 226 concentration was determined

  19. Ecology of Estuarine Macrobenthos

    NARCIS (Netherlands)

    Herman, P.M.J.; Middelburg, J.J.; Koppel, J. van de; Heip, C.H.R.

    1999-01-01

    Macrobenthos is an important component of estuarine ecosystems. Based on a cross-system comparison, we show that estuarine macrobenthos may directly process a significant portion of the system-wide primary production, and that estuarine macrobenthic biomass may be predicted from primary production

  20. Spatial variability in surface-water pCO2 and gas exchange in the world's largest semi-enclosed estuarine system: St. Lawrence Estuary (Canada)

    Science.gov (United States)

    Dinauer, Ashley; Mucci, Alfonso

    2017-07-01

    The incomplete spatial coverage of CO2 partial pressure (pCO2) measurements across estuary types represents a significant knowledge gap in current regional- and global-scale estimates of estuarine CO2 emissions. Given the limited research on CO2 dynamics in large estuaries and bay systems, as well as the sources of error in the calculation of pCO2 (carbonic acid dissociation constants, organic alkalinity), estimates of air-sea CO2 fluxes in estuaries are subject to large uncertainties. The Estuary and Gulf of St. Lawrence (EGSL) at the lower limit of the subarctic region in eastern Canada is the world's largest estuarine system, and is characterized by an exceptional richness in environmental diversity. It is among the world's most intensively studied estuaries, yet there are no published data on its surface-water pCO2 distribution. To fill this data gap, a comprehensive dataset was compiled from direct and indirect measurements of carbonate system parameters in the surface waters of the EGSL during the spring or summer of 2003-2016. The calculated surface-water pCO2 ranged from 435 to 765 µatm in the shallow partially mixed upper estuary, 139-578 µatm in the deep stratified lower estuary, and 207-478 µatm along the Laurentian Channel in the Gulf of St. Lawrence. Overall, at the time of sampling, the St. Lawrence Estuary served as a very weak source of CO2 to the atmosphere, with an area-averaged CO2 degassing flux of 0.98 to 2.02 mmol C m-2 d-1 (0.36 to 0.74 mol C m-2 yr-1). A preliminary analysis revealed that respiration (upper estuary), photosynthesis (lower estuary), and temperature (Gulf of St. Lawrence) controlled the spatial variability in surface-water pCO2. Whereas we used the dissociation constants of Cai and Wang (1998) to calculate estuarine pCO2, formulations recommended for best practices in open ocean environments may underestimate pCO2 at low salinities, while those of Millero (2010) may result in overestimates.

  1. A survey of Vibrio cholerae O1 and O139 in estuarine waters and sediments of Beira, Mozambique

    CSIR Research Space (South Africa)

    Du Preez, M

    2010-10-01

    Full Text Available Natural Resources and the Environment, CSIR, PO Box 395, Pretoria 0001, South Africa 2 Laborat?rio de Higiene de Aguas e Alimentos, Centro de Higiene Ambiental e Exames M?dicos, Beira, Mozambique Abstract This study determined whether the estuarine..., HASAN NA, BHUIYAN NA, NAIR GB, SIDDIQUE AK, SACK DA, AHSAN S, HUQ A, SACK RB and COLWELL RR (2006b) Effect of transport at ambient temperature on detection and isolation of Vibrio cholerae from environmental samples. Appl. Environ. Microbiol. 72 (3...

  2. Fundamentals of estuarine physical oceanography

    CERN Document Server

    Bruner de Miranda, Luiz; Kjerfve, Björn; Castro Filho, Belmiro Mendes de

    2017-01-01

    This book provides an introduction to the complex system functions, variability and human interference in ecosystem between the continent and the ocean. It focuses on circulation, transport and mixing of estuarine and coastal water masses, which is ultimately related to an understanding of the hydrographic and hydrodynamic characteristics (salinity, temperature, density and circulation), mixing processes (advection and diffusion), transport timescales such as the residence time and the exposure time. In the area of physical oceanography, experiments using these water bodies as a natural laboratory and interpreting their circulation and mixing processes using theoretical and semi-theoretical knowledge are of fundamental importance. Small-scale physical models may also be used together with analytical and numerical models. The book highlights the fact that research and theory are interactive, and the results provide the fundamentals for the development of the estuarine research.

  3. Traditional Mapuche ecological knowledge in Patagonia, Argentina: fishes and other living beings inhabiting continental waters, as a reflection of processes of change.

    Science.gov (United States)

    Aigo, Juana; Ladio, Ana

    2016-12-07

    Understanding how people interpret environmental change and develop practices in response to such change is essential to comprehend human resource use. In the cosmology of the American indigenous peoples, as among the Mapuche people, freshwater systems are considered a living entity, where animals have an enormous role to play in the universe of meaning. However, human adaptive responses to freshwater system dynamics are scarcely examined. In this work a survey is carried out in three Mapuche communities of Argentine Patagonia to assess their traditional knowledge of the fishes and other non-human living beings that inhabit lakes and rivers. Both material and symbolic aspects are included, as are the differences in knowledge and use of the fishes between past and present times. Our methods were based on a quali-quantitative fieldwork approach. In-depth interviews were carried out with 36 individuals from three rural Mapuche populations in Neuquén province (Patagonia, Argentina). Free listing was used for inquiring about fish knowledge and use. Fishes were identified scientifically and ethnotaxonomically. In-depth analysis of the discourses was conducted, documenting the recognition, perception, and cultural significance of fluvial environments and their inhabitants. Quantitative survey results were analyzed with categorical statistical methods. The body of knowledge of the communities studied reflects the socio-environmental changes experienced by Patagonian freshwater bodies. According to local perception, non-human beings live in these water bodies, guarding the environment, and they should not be disturbed. At present, five different fish species are identified, three of which are exotic, having been introduced at the beginning of the 20th century by the white man. These exotic trout (Oncorhynchus mykiss and Salvelinus fontinalis) are considered ill omens, indicators of the white man's presence, and therefore their appearance presages negative events for the

  4. Evidence of estrogenic endocrine disruption in smallmouth and largemouth bass inhabiting Northeast U.S. national wildlife refuge waters: A reconnaissance study.

    Science.gov (United States)

    Iwanowicz, L R; Blazer, V S; Pinkney, A E; Guy, C P; Major, A M; Munney, K; Mierzykowski, S; Lingenfelser, S; Secord, A; Patnode, K; Kubiak, T J; Stern, C; Hahn, C M; Iwanowicz, D D; Walsh, H L; Sperry, A

    2016-02-01

    Intersex as the manifestation of testicular oocytes (TO) in male gonochoristic fishes has been used as an indicator of estrogenic exposure. Here we evaluated largemouth bass (Micropterus salmoides) or smallmouth bass (Micropterus dolomieu) form 19 National Wildlife Refuges (NWRs) in the Northeast U.S. inhabiting waters on or near NWR lands for evidence of estrogenic endocrine disruption. Waterbodies sampled included rivers, lakes, impoundments, ponds, and reservoirs. Here we focus on evidence of endocrine disruption in male bass evidenced by gonad histopathology including intersex or abnormal plasma vitellogenin (Vtg) concentrations. During the fall seasons of 2008-2010, we collected male smallmouth bass (n=118) from 12 sites and largemouth bass (n=173) from 27 sites. Intersex in male smallmouth bass was observed at all sites and ranged from 60% to 100%; in male largemouth bass the range was 0-100%. Estrogenicity, as measured using a bioluminescent yeast reporter, was detected above the probable no effects concentration (0.73ng/L) in ambient water samples from 79% of the NWR sites. Additionally, the presence of androgen receptor and glucocorticoid receptor ligands were noted as measured via novel nuclear receptor translocation assays. Mean plasma Vtg was elevated (>0.2mg/ml) in male smallmouth bass at four sites and in male largemouth bass at one site. This is the first reconnaissance survey of this scope conducted on US National Wildlife Refuges. The baseline data collected here provide a necessary benchmark for future monitoring and justify more comprehensive NWR-specific studies. Published by Elsevier Inc.

  5. Evidence of estrogenic endocrine disruption in smallmouth and largemouth bass inhabiting Northeast U.S. National Wildlife Refuge waters: A reconnaissance study

    Science.gov (United States)

    Iwanowicz, Luke R.; Blazer, Vicki; Pinkney, A.E.; Guy, C.P.; Major, A.M.; Munney, K.; Mierzykowski, S.; Lingenfelser, S.; Secord, A.; Patnode, K.; Kubiak, T.J.; Stern, C.; Hahn, Cassidy M.; Iwanowicz, Deborah; Walsh, Heather L.; Sperry, Adam J.

    2016-01-01

    Intersex as the manifestation of testicular oocytes (TO) in male gonochoristic fishes has been used as an indicator of estrogenic exposure. Here we evaluated largemouth bass (Micropterus salmoides) or smallmouth bass (Micropterus dolomieu) form 19 National Wildlife Refuges (NWRs) in the Northeast U.S. inhabiting waters on or near NWR lands for evidence of estrogenic endocrine disruption. Waterbodies sampled included rivers, lakes, impoundments, ponds, and reservoirs. Here we focus on evidence of endocrine disruption in male bass evidenced by gonad histopathology including intersex or abnormal plasma vitellogenin (Vtg) concentrations. During the fall seasons of 2008–2010, we collected male smallmouth bass (n=118) from 12 sites and largemouth bass (n=173) from 27 sites. Intersex in male smallmouth bass was observed at all sites and ranged from 60% to 100%; in male largemouth bass the range was 0–100%. Estrogenicity, as measured using a bioluminescent yeast reporter, was detected above the probable no effects concentration (0.73 ng/L) in ambient water samples from 79% of the NWR sites. Additionally, the presence of androgen receptor and glucocorticoid receptor ligands were noted as measured via novel nuclear receptor translocation assays. Mean plasma Vtg was elevated (>0.2 mg/ml) in male smallmouth bass at four sites and in male largemouth bass at one site. This is the first reconnaissance survey of this scope conducted on US National Wildlife Refuges. The baseline data collected here provide a necessary benchmark for future monitoring and justify more comprehensive NWR-specific studies.

  6. Influence of the geologic and geomorphologic characteristics and of crab burrows on the interrelation between surface water and groundwater in an estuarine coastal wetland

    Science.gov (United States)

    Carol, Eleonora S.; Kruse, Eduardo E.; Pousa, Jorge L.

    2011-06-01

    SummaryThe interrelation between surface water and groundwater in intertidal flats is often studied through mathematical models. In many cases these models need to be supported by an integral analysis of the geologic, geomorphologic, hydrologic and biological characteristics of the environment that are to be obtained from field surveys. The marshy environment of the River Ajo in the Samborombon Bay wetland, Argentina, is a typical example of an estuarine coastal zone. Geologic and geomorphologic surveys were carried out, as well as measurements of surface water and groundwater level changes as a response of the aquifer to tidal forcing. The banks of the River Ajo are either scarped with storm flats, or mildly sloped with intertidal flats and numerous crab burrows. Sediments are mainly silty-clayey with low permeability, and lie over silty-sandy layers. At the erosion scarps the tidal wave enters the aquifer as a sub-horizontal flow through the pore space of the sediments. The tidal range in the aquifer depends on the lithological characteristics of the sediments and on the side changes of their hydraulic conductivity. The rise of the water table at high water and its subsequent fall are nearly sinusoidal, with a period similar to that of the tide at the river. At the intertidal flats, instead, the tidal wave enters the aquifer mainly as a sub-vertical flow through the crab burrows. As the crab burrows are not interconnected, they are not distinct pathways for preferential flow. Therefore, the groundwater flux into the river is very slow during low water, and the recovery of the water table takes a long time. The tidal influence upon the water table on both kinds of banks affects only a narrow strip of the aquifer. Not only are the characteristics of the marshy environment of the River Ajo representative of most of the Samborombon Bay wetland; they can also be extended to other similar coastal wetlands to help preserve these invaluable environments.

  7. Tidal-Fluvial and Estuarine Processes in the Lower Columbia River: II. Water Level Models, Floodplain Wetland Inundation, and System Zones

    Energy Technology Data Exchange (ETDEWEB)

    Jay, David A.; Borde, Amy B.; Diefenderfer, Heida L.

    2016-04-26

    Spatially varying water-level regimes are a factor controlling estuarine and tidal-fluvial wetland vegetation patterns. As described in Part I, water levels in the Lower Columbia River and estuary (LCRE) are influenced by tides, river flow, hydropower operations, and coastal processes. In Part II, regression models based on tidal theory are used to quantify the role of these processes in determining water levels in the mainstem river and floodplain wetlands, and to provide 21-year inundation hindcasts. Analyses are conducted at 19 LCRE mainstem channel stations and 23 tidally exposed floodplain wetland stations. Sum exceedance values (SEVs) are used to compare wetland hydrologic regimes at different locations on the river floodplain. A new predictive tool is introduced and validated, the potential SEV (pSEV), which can reduce the need for extensive new data collection in wetland restoration planning. Models of water levels and inundation frequency distinguish four zones encompassing eight reaches. The system zones are the wave- and current-dominated Entrance to river kilometer (rkm) 5; the Estuary (rkm-5 to 87), comprised of a lower reach with salinity, the energy minimum (where the turbidity maximum normally occurs), and an upper estuary reach without salinity; the Tidal River (rkm-87 to 229), with lower, middle, and upper reaches in which river flow becomes increasingly dominant over tides in determining water levels; and the steep and weakly tidal Cascade (rkm-229 to 234) immediately downstream from Bonneville Dam. The same zonation is seen in the water levels of floodplain stations, with considerable modification of tidal properties. The system zones and reaches defined here reflect geological features and their boundaries are congruent with five wetland vegetation zones

  8. The Validity Chlorophyll-a Estimation by Sun Induced Fluorescence in Estuarine Waters: An Analysis of Long-term (2003-2011) Water Quality Data from Tampa Bay, Florida (USA)

    Science.gov (United States)

    Moreno-Madrinan, Max Jacobo; Fischer, Andrew

    2012-01-01

    Satellite observation of phytoplankton concentration or chlorophyll-a is an important characteristic, critically integral to monitoring coastal water quality. However, the optical properties of estuarine and coastal waters are highly variable and complex and pose a great challenge for accurate analysis. Constituents such as suspended solids and dissolved organic matter and the overlapping and uncorrelated absorptions in the blue region of the spectrum renders the blue-green ratio algorithms for estimating chlorophyll-a inaccurate. Measurement of sun-induced chlorophyll fluorescence, on the other hand, which utilizes the near infrared portion of the electromagnetic spectrum, may provide a better estimate of phytoplankton concentrations. While modelling and laboratory studies have illustrated both the utility and limitations of satellite baseline algorithms based on the sun induced chlorophyll fluorescence signal, few have examined the empirical validity of these algorithms using a comprehensive long term in situ data set. In an unprecedented analysis of a long term (2003-2011) in situ monitoring data from Tampa Bay, Florida (USA), we assess the validity of the FLH product from the Moderate Resolution Imaging Spectrometer (MODIS) against chlorophyll ]a and a suite of water quality parameters taken in a variety of conditions throughout a large optically complex estuarine system. A systematic analysis of sampling sites throughout the bay is undertaken to understand how the relationship between FLH and in situ chlorophyll-a responds to varying conditions within the estuary including water depth, distance from shore and structures and eight water quality parameters. From the 39 station for which data was derived, 22 stations showed significant correlations when the FLH product was matched with in situ chlorophyll-alpha data. The correlations (r2) for individual stations within Tampa Bay ranged between 0.67 (n=28, pless than 0.01) and-0.457 (n=12, p=.016), indicating that

  9. In-field determination of trace dissolved manganese in estuarine and coastal waters with automatic on-line preconcentration and flame atomic fluorescence spectrometry.

    Science.gov (United States)

    Feng, Sichao; Yuan, Dongxing; Huang, Yongming; Lin, Kunning; Zhou, Tingjin

    2017-04-22

    An automatic on-line preconcentration and detection system for analysis of trace dissolved manganese (Mn) in estuarine and coastal waters was established, using preconcentration with IDA chelating resin and detection with flame atomic fluorescence spectrometer (FAFS). The rinse (pre-eluent) solution was optimized, for removing the interference ions while retaining the target element. It was found that the interference ions affected the chelating efficiency of Mn, causing variation of the detection blank and sensitivity. This effect varied when sample volume presented as preconcentration time changed. The influence at preconcentration times of 120 s, 30 s and 10 s were carefully investigated and reported. Ten folds of the foreign trace metals Zn, Cu, Ni, Fe, and Al did not show obvious interference on Mn preconcentration and detection. The method detection limit was 0.9 nmol L -1 (n = 7, preconcentration time 120 s). The linear detection range could be adjusted with designed preconcentration time. In addition to high precision and accuracy, the proposed analytical system had the advantages of high integration, and required normal site preparation, low energy supply and simple auxiliary equipment, which was appropriate for in-field operation. Compared with other common in-field applied molecular spectrometry instruments, the inherent high selectivity and multi-element applicability of FAFS highlighted the superiority and potential of the proposed analytical system. It was successfully applied to in-field vehicle-board determination of dissolved Mn in coastal waters around Xiamen, Fujian, China, and it was also used to analyze natural water samples collected from the Jiulongjiang Estuary, Fujian, China. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. A mathematical model for the design and interpretation of tracer experiments intended to measure the T90 in estuarine coastal waters

    International Nuclear Information System (INIS)

    Suarez Antola, R.

    2006-07-01

    In highly stratified estuarine waters, with significant sediment loads, it is fairly difficult to predict the T90 , the time scale that characterizes the bacterial inactivation or death, using mathematical formulae, so that suitable experiments must be done using tracers to measure physical dilution and microbiological methods to measure bacterial disappearance or inactivation. The location and characteristics of a second sewage out fall for the city of Montevideo is being determined. In this framework, several experiments with tracers were done to measure the self-purifying capacity of the coastal waters at the selected site. Due to the difficulties in the design and interpretation of the measurements, special mathematical models were constructed and applied to help in obtaining a deeper understanding of the complex advection-dispersion-inactivation processes. In this report the construction and the solution of the equations of an analytical model that guided all the subsequent modelling activities is described. The tracer and the bacteria fields are obtained as products of a function of time and the horizontal coordinates by a series of decaying exponential functions of time weighted by functions of depth. The quotient between the bacteria concentration and the tracer concentration, that is commonly used to determine a global value of T90 , taking suitable average values after a long enough transient, is studied. A procedure that may be used to summarize the field of local inactivation times by a few parameters, determined by tracer experiments and microbiological measurements, is discussed. A half-empirical correlation formula between the T90 parameter and the main variables of the body of receiving waters is suggested from the results of tracer experiments and other sources of information. The advantages and limitations of the modelling approach used in this case are assessed and some possible improvements are briefly outlined

  11. A mathematical model for the design and interpretation of tracer experiments intended to measure the T90 in estuarine coastal waters

    International Nuclear Information System (INIS)

    Suarez Antola, R.

    2006-03-01

    In highly stratified estuarine waters, with significant sediment loads, it is fairly difficult to predict the T90, the time scale that characterizes the bacterial inactivation or death, using mathematical formulae, so that suitable experiments must be done using tracers to measure physical dilution and microbiological methods to measure bacterial disappearance or inactivation. The location and characteristics of a second sewage outfall for the city of Montevideo is being determined. In this framework, several experiments with tracers were done to measure the self-purifying capacity of the coastal waters at the selected site. Due to the difficulties in the design and interpretation of the measurements, special mathematical models were constructed and applied to help in obtaining a deeper understanding of the complex advection-dispersion-inactivation processes. In this report the construction and the solution of the equations of an analytical model that guided all the subsequent modelling activities is described. The tracer and the bacteria fields are obtained as products of a function of time and the horizontal coordinates by a series of decaying exponential functions of time weighted by functions of depth. The quotient between the bacteria concentration and the tracer concentration, that is commonly used to determine a global value of T90 , taking suitable average values after a long enough transient, is studied. A procedure that may be used to summarize the field of local inactivation times by a few parameters, determined by tracer experiments and microbiological measurements, is discussed. A half-empirical correlation formula between the T90 parameter and the main variables of the body of receiving waters is suggested from the results of tracer experiments and other sources of information. The advantages and limitations of the modelling approach used in this case are assessed and some possible improvements are briefly outlined

  12. A Lab-On-Chip Phosphate Analyzer for Long-term In Situ Monitoring at Fixed Observatories: Optimization and Performance Evaluation in Estuarine and Oligotrophic Coastal Waters

    Directory of Open Access Journals (Sweden)

    Maxime M. Grand

    2017-08-01

    Full Text Available The development of phosphate sensors suitable for long-term in situ deployments in natural waters, is essential to improve our understanding of the distribution, fluxes, and biogeochemical role of this key nutrient in a changing ocean. Here, we describe the optimization of the molybdenum blue method for in situ work using a lab-on-chip (LOC analyzer and evaluate its performance in the laboratory and at two contrasting field sites. The in situ performance of the LOC sensor is evaluated using hourly time-series data from a 56-day trial in Southampton Water (UK, as well as a month-long deployment in the subtropical oligotrophic waters of Kaneohe Bay (Hawaii, USA. In Kaneohe Bay, where phosphate concentrations were characteristic of the dry season (0.13 ± 0.03 μM, n = 704, the in situ sensor accuracy was 16 ± 12% and a potential diurnal cycle in phosphate concentrations was observed. In Southampton Water, the sensor data (1.02 ± 0.40 μM, n = 1,267 were accurate to ±0.10 μM relative to discrete reference samples. Hourly in situ monitoring revealed striking tidal and storm derived fluctuations in phosphate concentrations in Southampton Water that would not have been captured via discrete sampling. We show the impact of storms on phosphate concentrations in Southampton Water is modulated by the spring-neap tidal cycle and that the 10-fold decline in phosphate concentrations observed during the later stages of the deployment was consistent with the timing of a spring phytoplankton bloom in the English Channel. Under controlled laboratory conditions in a 250 L tank, the sensor demonstrated an accuracy and precision better than 10% irrespective of the salinity (0–30, turbidity (0–100 NTU, colored dissolved organic matter (CDOM concentration (0–10 mg/L, and temperature (5–20°C of the water (0.3–13 μM phosphate being analyzed. This work demonstrates that the LOC technology is mature enough to quantify the influence of stochastic events on

  13. RELATIONS BETWEEN BACTERIAL NITROGEN METABOLISM AND GROWTH EFFICIENCY IN AN ESTUARINE AND AN OPEN-WATER ECOSYSTEM

    Science.gov (United States)

    Bacterial uptake or release of dissolved nitrogen compounds (amino nitrogen, urea, ammonium and nitrate) were examined in 0.8 |m filtered water from an estuary (Santa Rosa Sound [SRS], northwestern Florida) and an open-water location in the Gulf of Mexico [GM]. The bacterial nutr...

  14. GoM Coastal and Estuarine Biopsy Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Small vessel surveys are conducted within estuarine and nearshore coastal waters to collect tissue biopsy samples from bottlenose dolphins. Visual surveys are...

  15. Estuarine response of fluoride - Investigations in Azhikode Estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Balachandran, K.K.; Joseph, T.; Sankaranarayanan, V.N.

    Concentrations of fluoride in Azhikode estuarine region (Kerala, India) were measured as a function of chlorinity during the different seasons. The type of behaviour indicated that fluoride was regulated by sea water incursion alone. Fluoride...

  16. Shrimp farming in estuarine environment: Points to ponder

    Digital Repository Service at National Institute of Oceanography (India)

    Achuthankutty, C.T.

    of the expansion has taken place around the estuarine area as it facilitates water exchange and waste disposal. In semi-intensive and extensive type of farming practices, use of different types of chemicals and antibiotics, artificial feeds, probiotics...

  17. Water quality assessment of Gautami-Godavari mangrove estuarine ecosystem of Andhra Pradesh, India during September 2001

    Digital Repository Service at National Institute of Oceanography (India)

    Tripathy, S.C.; Ray, A.K.; Patra, S.; Sarma, V.V.

    Some chemical and biological parameters were analysed at sixteen stations in the mangrove ecosystem, of the neighbouring Gautami-Godavari (GG) river estuary and Kakinada (KKD) bay to understand the present status of water quality and the impact...

  18. Physicochemical Factors Influence the Abundance and Culturability of Human Enteric Pathogens and Fecal Indicator Organisms in Estuarine Water and Sediment

    Directory of Open Access Journals (Sweden)

    Francis Hassard

    2017-10-01

    Full Text Available To assess fecal pollution in coastal waters, current monitoring is reliant on culture-based enumeration of bacterial indicators, which does not account for the presence of viable but non-culturable or sediment-associated micro-organisms, preventing effective quantitative microbial risk assessment (QMRA. Seasonal variability in viable but non-culturable or sediment-associated bacteria challenge the use of fecal indicator organisms (FIOs for water monitoring. We evaluated seasonal changes in FIOs and human enteric pathogen abundance in water and sediments from the Ribble and Conwy estuaries in the UK. Sediments possessed greater bacterial abundance than the overlying water column, however, key pathogenic species (Shigella spp., Campylobacter jejuni, Salmonella spp., hepatitis A virus, hepatitis E virus and norovirus GI and GII were not detected in sediments. Salmonella was detected in low levels in the Conwy water in spring/summer and norovirus GII was detected in the Ribble water in winter. The abundance of E. coli and Enterococcus spp. quantified by culture-based methods, rarely matched the abundance of these species when measured by qPCR. The discrepancy between these methods was greatest in winter at both estuaries, due to low CFU's, coupled with higher gene copies (GC. Temperature accounted for 60% the variability in bacterial abundance in water in autumn, whilst in winter salinity explained 15% of the variance. Relationships between bacterial indicators/pathogens and physicochemical variables were inconsistent in sediments, no single indicator adequately described occurrence of all bacterial indicators/pathogens. However, important variables included grain size, porosity, clay content and concentrations of Zn, K, and Al. Sediments with greater organic matter content and lower porosity harbored a greater proportion of non-culturable bacteria (including dead cells and extracellular DNA in winter. Here, we show the link between physicochemical

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

    Science.gov (United States)

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

    2017-10-01

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

  20. Laboratory calibration and field testing of the Chemcatcher-Metal for trace levels of rare earth elements in estuarine waters.

    Science.gov (United States)

    Petersen, Jördis; Pröfrock, Daniel; Paschke, Albrecht; Broekaert, Jose A C; Prange, Andreas

    2015-10-01

    Little knowledge is available about water concentrations of rare earth elements (REEs) in the marine environment. The direct measurement of REEs in coastal waters is a challenging task due to their ultra-low concentrations as well as the high salt content in the water samples. To quantify these elements at environmental concentrations (pg L(-1) to low ng L(-1)) in coastal waters, current analytical techniques are generally expensive and time consuming, and require complex chemical preconcentration procedures. Therefore, an integrative passive sampler was tested as a more economic alternative sampling approach for REE analysis. We used a Chemcatcher-Metal passive sampler consisting of a 3M Empore Chelating Disk as the receiving phase, as well as a cellulose acetate membrane as the diffusion-limiting layer. The effect of water turbulence and temperature on the uptake rates of REEs was analyzed during 14-day calibration experiments by a flow-through exposure tank system. The sampling rates were in the range of 0.42 mL h(-1) (13 °C; 0.25 m s(-1)) to 4.01 mL h(-1) (13 °C; 1 m s(-1)). Similar results were obtained for the different REEs under investigation. The water turbulence was the most important influence on uptake. The uptake rates were appropriate to ascertain time-weighted average concentrations of REEs during a field experiment in the Elbe Estuary near Cuxhaven Harbor (exposure time 4 weeks). REE concentrations were determined to be in the range 0.2 to 13.8 ng L(-1), where the highest concentrations were found for neodymium and samarium. In comparison, most of the spot samples measured along the Chemcatcher samples had REE concentrations below the limit of detection, in particular due to necessary dilution to minimize the analytical problems that arise with the high salt content in marine water samples. This study was among the first efforts to measure REE levels in the field using a passive sampling approach. Our results suggest that passive samplers could be

  1. An inversion of the estuarine circulation by sluice water discharge and its impact on suspended sediment transport

    NARCIS (Netherlands)

    Schulz, K.; Gerkema, T.

    2018-01-01

    The Wadden Sea is characterized by a complex topography of branching channels and intertidal flats, in which the interplay between fresh water discharges, wind forcing and the tidal current causes sediment transport rates and direction to be highly variable in space and time. During three field

  2. Marine and Estuarine Pollution.

    Science.gov (United States)

    Reish, Donald J.

    1978-01-01

    Presents a literature review of the effects of various pollutants on marine and estuarine organisms, covering publications of 1976-77. This review includes: (1) effects of pesticides, dredging, dumping, sludge, and petroleum hydrocarbons; and (2) diseases and tissue abnormalities. A list of 441 references is also presented. (HM)

  3. Artificial Neural Network forecasting of storm surge water levels at major estuarine ports to supplement national tide-surge models and improve port resilience planning

    Science.gov (United States)

    French, Jon; Mawdsley, Robert; Fujiyama, Taku; Achuthan, Kamal

    2017-04-01

    Effective prediction of tidal storm surge is of considerable importance for operators of major ports, since much of their infrastructure is necessarily located close to sea level. Storm surge inundation can damage critical elements of this infrastructure and significantly disrupt port operations and downstream supply chains. The risk of surge inundation is typically approached using extreme value analysis, while short-term forecasting generally relies on coastal shelf-scale tide and surge models. However, extreme value analysis does not provide information on the duration of a surge event and can be sensitive to the assumptions made and the historic data available. Also, whilst regional tide and surge models perform well along open coasts, their fairly coarse spatial resolution means that they do not always provide accurate predictions for estuarine ports. As part of a NERC Environmental Risks to Infrastructure Innovation Programme project, we have developed a tool that is specifically designed to forecast the North Sea storm surges on major ports along the east coast of the UK. Of particular interest is the Port of Immingham, Humber estuary, which handles the largest volume of bulk cargo in the UK including major flows of coal and biomass for power generation. A tidal surge in December 2013, with an estimated return period of 760 years, partly flooded the port, damaged infrastructure and disrupted operations for several weeks. This and other recent surge events highlight the need for additional tools to supplement the national UK Storm Tide Warning Service. Port operators are also keen to have access to less computationally expensive forecasting tools for scenario planning and to improve their resilience to actual events. In this paper, we demonstrate the potential of machine learning methods based on Artificial Neural Networks (ANNs) to generate accurate short-term forecasts of extreme water levels at estuarine North Sea ports such as Immingham. An ANN is

  4. Contamination by PAHs, PCBs, PCPs and heavy metals in the Mecoacan lake Estuarine water and sediments after oil spilling

    Energy Technology Data Exchange (ETDEWEB)

    Armenta-Arteaga, G. [Univ. Juarez Autonoma de Tabasco, D.A., Ciencias Biologicas, Villahermosa, Tabasco (Mexico); Elizalde-Gonzalez, M.P. [Centro de Quimica, Univ. Autonoma de Puebla, Puebla, Pue (Mexico)

    2003-07-01

    Intention, Goal, Scope, Background. Environmental pollution caused by oil spills is a major ecological problem. Oil contamination in the environment is primarily evaluated by measuring the chemical concentrations of hydrocarbons. The results of chemical analyses are important for estimating water and sediment quality in the risk assessment to the flora and fauna of oil-contaminated sites. In the world there are lake ecosystems under permanent chemical stress due to urbanization and the oil industry. Studies, however, have been generally limited to petroleum compounds and have not considered other pollutants of the site like PCBs, polychlorinated pesticides and heavy metals. Objective. Water and sediment from stations in the Mecoacan Lake in the Mexican State of Tabasco were analyzed for polycyclic aromatic compounds (PAHs), aliphatic hydrocarbons (AHs), polychlorinated biphenyls (PCBs), polychlorinated pesticides (PCPs) and heavy metals. The objective of this study was to examine the contaminant levels of the samples collected in February 1993 and 1996 after oil spills at the Mecoacan petroleum region. The goals of this study were to reveal the effect of the spills on the distribution of the hydrocarbons and assess the toxicological significance of the levels found. In addition, our aim was to examine the distribution of the PAHs in sediments from Mecoacan originated from both pyrolytic and petrogenic sources. Methods. Samples were collected from 19 stations and prepared according to the CARIPOL (Caribbean Pollution) methodology of the United Nations Environmental Programme (1992) of the Great Caribbean Region for hydrocarbons in marine and coastal water, and sediments. The gas-chromatographic and atomic absorption analysis of the samples was performed after sampling. (orig.)

  5. Variation in biochemical composition of Saccharina latissima and Laminaria digitata along an estuarine salinity gradient in inner Danish waters

    DEFF Research Database (Denmark)

    Nielsen, Mette Møller; Manns, Dirk Martin; D'Este, Martina

    2016-01-01

    In European kelp cultivation, knowledge on the spatial variation in biomass productivity and quality needs to be established. The present study provides a detailed overview of the biochemical composition and biomass production potential of Saccharina latissima and Laminaria digitata along...... a salinity gradient (16–31 PSU) in inner Danish waters. We discuss the results in a cultivation perspective, and evaluate the potential use of Laminariales as an energy feedstock, a feed additive and a bioremediation tool for mitigating eutrophication. We found the highest biomass production potential......, the highest protein content (7.5% of dry matter), and the highest capacity for bio-remediation of nitrogen (1.88% N of dry matter) at high salinities, as opposed to the highest concentrations of fermentable sugars (90% of dry matter) and pigments at low salinities. Thus, areas suitable for high biomass...

  6. Ecohydraulics and Estuarine Wetland Rehabilitation

    Science.gov (United States)

    Rodriguez, J. F.; Howe, A.; Saintilan, N.; Spencer, J.

    2004-12-01

    The hydraulics or water flow in wetlands is known to be a key factor influencing ecosystem development in estuarine wetland environments. The relationship is indirect, with the hydraulics of wetlands influencing a host of factors including soil salinity, waterlogging, sediment transport, sediment chemistry, vegetation dispersal and growth and nutrient availability and cycling. The relationship is also not one way, with the hydraulics of wetlands being influenced by plant and animal activity. Understanding these complex interactions is fundamental for the adequate management of estuarine wetlands. Listed as a Wetland of International Importance under the 1971 Ramsar Convention, the Hunter River estuary is regarded as the most significant site for migratory shorebirds in New South Wales, Australia. Over the past 20 years, the number of migratory shorebirds in the estuary has sharply declined from 8,000 to 4,000 approx. Alteration of bird habitat is believed to be one of the reasons for this alarming trend. In 2004 we started a three-year program to investigate the links between hydraulics, sediment, benthic invertebrates, vegetation and migratory shorebird habitat in the estuary. During the first year we have focused on a highly disturbed part of the Hunter estuary wetlands located on Ash Island. The area is one of the major roosting sites in the estuary and is characterized by a complex hydraulic regime due to a restricted tidal interchange with the Hunter River and the presence of infrastructure for the maintenance of power lines (i.e., roads, bridges, culverts). Salt marshes, mudflat and mangroves are the dominant vegetation types. The monitoring program includes measurements of water levels, salinity, discharge, velocity, turbulence, sediment transport and deposition, plant species and density, soil composition and benthic invertebrates coordinated with observations of bird habitat utilization on a number of locations throughout the wetland and for different flow

  7. ESTIMATION OF THE POPULATION EXPOSURE DOSES FROM NATURAL AND ARTIFICIAL RADIONUCLIDES DUE TO DRINKING-WATER CONSUMPTION FOR THE INHABITANTS OF DIFFERENT AREAS OF RUSSIAN FEDERATION

    Directory of Open Access Journals (Sweden)

    Ju. N. Goncharova

    2010-01-01

    Full Text Available The report contains data on specific activity values of natural and artificial radionuclides in the water of underground and surface sources in 19 areas of Russian Federation and data on population internal exposure doses from drinking water consumption in these areas.

  8. Effect of thermal shock on developmental stages of estuarine fish. Final report

    International Nuclear Information System (INIS)

    Dean, J.M.

    1978-12-01

    Physiological data and ecological data show that the few estuarine spawners have a higher thermal tolerance in the embryonic and larval stages than do the freshwater, coastal, or oceanic spawning species. However, since all three groups (freshwater, estuarine, and oceanic spawners) occupy the estuary and coastal waters at different times of the year, knowledge of their physiology and ecology at different developmental or life cycle stages is critical for estuarine management decisions

  9. Comparisons of the composition and biogeographic distribution of the bacterial communities occupying South African thermal springs with those inhabiting deep subsurface fracture water.

    Science.gov (United States)

    Magnabosco, Cara; Tekere, Memory; Lau, Maggie C Y; Linage, Borja; Kuloyo, Olukayode; Erasmus, Mariana; Cason, Errol; van Heerden, Esta; Borgonie, Gaetan; Kieft, Thomas L; Olivier, Jana; Onstott, Tullis C

    2014-01-01

    South Africa has numerous thermal springs that represent topographically driven meteoric water migrating along major fracture zones. The temperature (40-70°C) and pH (8-9) of the thermal springs in the Limpopo Province are very similar to those of the low salinity fracture water encountered in the South African mines at depths ranging from 1.0 to 3.1 km. The major cation and anion composition of these thermal springs are very similar to that of the deep fracture water with the exception of the dissolved inorganic carbon and dissolved O2, both of which are typically higher in the springs than in the deep fracture water. The in situ biological relatedness of such thermal springs and the subsurface fracture fluids that feed them has not previously been evaluated. In this study, we evaluated the microbial diversity of six thermal spring and six subsurface sites in South Africa using high-throughput sequencing of 16S rRNA gene hypervariable regions. Proteobacteria were identified as the dominant phylum within both subsurface and thermal spring environments, but only one genera, Rheinheimera, was identified among all samples. Using Morisita similarity indices as a metric for pairwise comparisons between sites, we found that the communities of thermal springs are highly distinct from subsurface datasets. Although the Limpopo thermal springs do not appear to provide a new window for viewing subsurface bacterial communities, we report that the taxonomic compositions of the subsurface sites studied are more similar than previous results would indicate and provide evidence that the microbial communities sampled at depth are more correlated to subsurface conditions than geographical distance.

  10. Comparisons of the composition and biogeographic distribution of the bacterial communities occupying South African thermal springs with those inhabiting deep subsurface fracture water

    Science.gov (United States)

    Magnabosco, Cara; Tekere, Memory; Lau, Maggie C. Y.; Linage, Borja; Kuloyo, Olukayode; Erasmus, Mariana; Cason, Errol; van Heerden, Esta; Borgonie, Gaetan; Kieft, Thomas L.; Olivier, Jana; Onstott, Tullis C.

    2014-01-01

    South Africa has numerous thermal springs that represent topographically driven meteoric water migrating along major fracture zones. The temperature (40–70°C) and pH (8–9) of the thermal springs in the Limpopo Province are very similar to those of the low salinity fracture water encountered in the South African mines at depths ranging from 1.0 to 3.1 km. The major cation and anion composition of these thermal springs are very similar to that of the deep fracture water with the exception of the dissolved inorganic carbon and dissolved O2, both of which are typically higher in the springs than in the deep fracture water. The in situ biological relatedness of such thermal springs and the subsurface fracture fluids that feed them has not previously been evaluated. In this study, we evaluated the microbial diversity of six thermal spring and six subsurface sites in South Africa using high-throughput sequencing of 16S rRNA gene hypervariable regions. Proteobacteria were identified as the dominant phylum within both subsurface and thermal spring environments, but only one genera, Rheinheimera, was identified among all samples. Using Morisita similarity indices as a metric for pairwise comparisons between sites, we found that the communities of thermal springs are highly distinct from subsurface datasets. Although the Limpopo thermal springs do not appear to provide a new window for viewing subsurface bacterial communities, we report that the taxonomic compositions of the subsurface sites studied are more similar than previous results would indicate and provide evidence that the microbial communities sampled at depth are more correlated to subsurface conditions than geographical distance. PMID:25566203

  11. Comparisons of the composition and biogeographic distribution of the bacterial communities occupying South African thermal springs with those inhabiting deep subsurface fracture water

    Directory of Open Access Journals (Sweden)

    Cara eMagnabosco

    2014-12-01

    Full Text Available South Africa has numerous thermal springs that represent topographically driven meteoric water migrating along major fracture zones. The temperature (40-70°C and pH (8-9 of the thermal springs in the Limpopo Province are very similar to those of the low salinity fracture water encountered in the South African mines at depths ranging from 1.0 to 3.1 km. The major cation and anion composition of these thermal springs are very similar to that of the deep fracture water with the exception of the dissolved inorganic carbon and dissolved O2, both of which are typically higher in the springs than in the deep fracture water. The in situ biological relatedness of such thermal springs and the subsurface fracture fluids that feed them has not previously been evaluated. In this study, we evaluated the microbial diversity of six thermal spring and six subsurface sites in South Africa using high-throughput sequencing of 16S rRNA gene hypervariable regions. Proteobacteria were identified as the dominant phylum within both subsurface and thermal spring environments, but only one genera, Rheinheimera, was identified among all samples. Using Morisita similarity indices as a metric for pairwise comparisons between sites, we found that the communities of thermal springs are highly distinct from subsurface datasets. Although the Limpopo thermal springs do not appear to provide a new window for viewing subsurface bacterial communities, we report that the taxonomic compositions of the subsurface sites studied are more similar than previous results would indicate and provide evidence that the microbial communities sampled at depth are more correlated to subsurface conditions than geographical distance.

  12. Patrones de resistencia a antibióticos de enterococos aislados de aguas estuarinas Antibiotic resistance patterns of enterococci isolated from estuarine waters

    Directory of Open Access Journals (Sweden)

    M. Baldini

    2008-03-01

    Full Text Available La llegada al ambiente de bacterias antibiótico-resistentes compromete su calidad higiénico sanitaria. Se analizó la prevalencia de diferentes especies de Enterococcus en aguas del estuario de Bahía Blanca y sus patrones de resistencia a los antibióticos. Se identificaron bioquímicamente 103 aislamientos . Para evaluar la resistencia a antibióticos se implementó la técnica de difusión en agar utilizando discos de vancomicina (Van 30 µg, gentamicina (GenH 120 µg, estreptomicina (StrH 300 µg, teicoplanina (T 30 µg, ampicilina (Am 10 µg y ciprofloxacina (CIP 5 µg, según normas del Clinical and Laboratory Standards Institute. Se identificaron siete especies de Enterococcus; Enterococcus faecium y Enterococcus faecalis resultaron ser las más frecuentes. El 1,9% de los enterococos presentó resistencia de alto nivel a los aminoglucósidos y no hubo aislamientos con resistencia simultánea a StrH y GenH. El 12,6% de los aislamientos resultó resistente a CIP. No se detectaron resistencias a los glucopéptidos, ni a la Am. El 34% de los aislamientos fue sensible a todos los antibióticos probados. Tradicionalmente, la vigilancia de la dispersión de resistencias bacterianas se realiza con microorganismos de muestras clínicas. Los hallazgos de este trabajo constituyen un dato relevante para el control de cepas resistentes, las que se creían circunscriptas al ámbito hospitalario y que, sin embargo, se encuentran circulando en el ambiente.The introduction of antibioticresistant bacteria to the environment, affects its hygienic-sanitary quality. The objective of this work is to study the prevalence and the antibiotic resistance patterns of enterococci species isolated from Bahía Blanca estuarine waters. One hundred and three isolates were biochemically identified as Enterococcus spp. The diffusion technique was implemented, by using disks of: vancomycin (Van 30 µg, gentamicin (GenH 120 µg, streptomycin (StrH 300 µg, teicoplanin (T

  13. Environmental management of estuarine areas: a proposal for conservation of water and biodiversity to the mangroves of the Paraiba do Sul River estuary, Gargaú, RJ

    Directory of Open Access Journals (Sweden)

    Edêmea Faria Carlos Rocha

    2016-12-01

    Full Text Available Being impacted by illegal occupation and untreated sewage release, the mangrove estuary of the Paraíba do Sul River has high biodiversity and provides various ecosystem services. In this study, we focused on strategies for sustainability promotion in Gargaú, a locality in this estuarine region, associating mangrove conservation to the uses of common resources practiced by locals. The main investigated issues were: “Would it be feasible to create a Conservation Unit in order to reinforce legal mechanisms to protect the mangrove?”; and “How does the local community see the scenario of environmental degradation and the proposal of creating a Conservation Unit in the region?”. Locals strongly depend on the estuarine area resources and perceive mangrove deforestation as well as untreated sewage release as the main causes of negative impacts. Despite not knowing what a Conservation Unit actually is, local key informants agreed to its creation after clarification of the categories and groups fixed by Brazilian legislation. Although accepting it with reservation, they understood it is a necessary measure to conserve the mangrove that sustains them.

  14. North Inlet-Winyah Bay National Estuarine Research Reserve's (NERR) Estuarine Surface Water Nutrient, Suspended Sediment, and Chlorophyll a Data for the North Inlet and Winyah Bay Estuaries, Georgetown, South Carolina: 1993-2001

    Data.gov (United States)

    Baruch Institute for Marine and Coastal Sciences, Univ of South Carolina — A one 1000 ml (one Liter) water sample was collected every 20 days at 2 hour and 4 minute intervals for 2 complete tidal cycles (26 hours) with an ISCO automated...

  15. Population growth, trophic level, and reproductive biology of two congeneric archer fishes (Toxotes chatareus, Hamilton 1822 and Toxotes jaculatrix, Pallas 1767) inhabiting Malaysian coastal waters.

    Science.gov (United States)

    Simon, K D; Bakar, Y; Samat, A; Zaidi, C C; Aziz, A; Mazlan, A G

    2009-12-01

    Population growth, trophic level, and some aspects of reproductive biology of two congeneric archer fish species, Toxotes chatareus and Toxotes jaculatrix, collected from Johor coastal waters, Malaysia, were studied. Growth pattern by length-weight relationship (W=aL(b)) for the sexes differed, and exhibited positive allometric growth (male, female and combined sexes of T. chatareus; female and combined sexes of T. jaculatrix) and isometric growth (male samples of T. jaculatrix only). Trophic levels of both species were analyzed based on 128 specimens. The results show that, in both species, crustaceans and insects were the most abundant prey items, and among crustaceans the red clawed crab Sesarma bidens and Formicidae family insects were the most represented taxa. The estimated mean trophic levels for T. chatareus and T. jaculatrix were 3.422+/-0.009 and 3.420+/-0.020, respectively, indicating that they are largely carnivores. Fecundity of T. chatareus ranged from 38 354 to 147 185 eggs for females with total length ranging from 14.5 to 22.5 cm and total body weight from 48.7 to 270.2 g, and T. jaculatrix 25 251 to 150 456 eggs for females with total length ranging from 12.2 to 23.0 cm and total body weight from 25.7 to 275.0 g. Differences in values of gonadosomatic and hepatosomatic indexes calculated for both species in this study may have resulted from uneven sample size ranges.

  16. General assessment of estuarine pollution

    Indian Academy of Sciences (India)

    Agricultural runoff contributes to high nutrient loads in estuaries. Their impacts on estuarine ecology – particularly responses of plankton and the influence on the food chain needs to be investigated.

  17. Management options for restoring estuarine dynamics and implications for ecosystems

    NARCIS (Netherlands)

    Ysebaert, Tom; Hoek, van der Dirk Jan; Wortelboer, Rick; Wijsman, Jeroen W.M.; Tangelder, Marijn; Nolte, Arno

    2016-01-01

    The Delta Works, a series of dams and barriers constructed in the 1960's-1980's changed the estuarine landscape of the Rhine-Meuse-Scheldt delta (SW Netherlands) into more stagnant and disengaged freshwater, brackish water or saltwater lakes. The remaining tidal systems were adapted by building a

  18. Algal stabilisation of estuarine sediments

    International Nuclear Information System (INIS)

    1992-01-01

    The presence of benthic microalgae can increase the stability of intertidal sediments and influence sediment fluxes within an estuarine environment. Therefore the relative importance of algal stabilisation needs to be understood to help predict the effects of a tidal barrage. The biogenic stabilisation of intertidal estuarine sediments by epipelic diatom films and the macrophyte Vaucheria was studied at three sites on the Severn Estuary. The cohesive strength meter (CSM) was developed to measure surface critical shear stress with varied algal density. A number of techniques have been used to determine the general in situ erodibility of cohesive estuarine sediments. The measurements of sediment shear strength and critical erosion velocity were investigated. Field experiments were undertaken to investigate the effect of algae on binding sediments, and a predictive method for the assessment of sediment stabilisation by algal binding was developed. (author)

  19. Spatial and temporal variability in the otolith chemistry of the Brazilian snapper Lutjanus alexandrei from estuarine and coastal environments.

    Science.gov (United States)

    Aschenbrenner, A; Ferreira, B P; Rooker, J R

    2016-07-01

    Otolith chemistry of juvenile and adult individuals of the Brazilian snapper Lutjanus alexandrei was measured to assess the utility of natural markers for investigating individual movements. Individuals were collected over a 3-year period (2010-2012) along the north-eastern coast of Brazil from both estuarine (juvenile to sub-adult stages) and coastal (sub-adult to adult stages) areas. Six elements ((7) Li, (24) Mg, (55) Mn, (59) Co, (88) Sr and (137) Ba) were measured in sectioned otoliths of L. alexandrei using laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). Edge composition analysis indicated that element:Ca ratios in the otoliths of juvenile and sub-adult L. alexandrei from estuaries were not significantly different among the three consecutive years (2010, 2011 and 2012), suggesting that physicochemical conditions within the nursery area investigated were temporally stable. Similarly, apart from two elements (Ba and Co), element:Ca ratios for larger L. alexandrei inhabiting coastal waters were also similar. In contrast, otolith chemistry of similar sized L. alexandrei from estuarine and coastal areas was significantly different (based on recently accreted material). Otolith Mn:Ca and Ba:Ca were both significantly higher for L. alexandrei collected in estuaries compared to fish from adjacent coastal reefs, while the opposite trend was observed for Sr:Ca. Given the pronounced differences in otolith chemistry between estuarine and coastal areas, element:Ca transects were constructed from the core to margin of the otoliths for adults (age 7+ years) collected on reefs to determine the timing of movement (ontogenetic migration) from estuarine to coastal areas. Based on observed patterns of decline for both Mn:Ca and Ba:Ca, it appears that L. alexandrei begin the move to more coastal habitats (i.e. lower element:Ca ratios) after age 2 years. The patterns observed for this species highlight the importance of conserving connectivity between

  20. Minimal incorporation of Deepwater Horizon oil by estuarine filter feeders

    International Nuclear Information System (INIS)

    Fry, Brian; Anderson, Laurie C.

    2014-01-01

    Highlights: • Oil from the Deepwater Horizon oil spill entered Louisiana bays in mid-2010. • Oil was used minimally (<1%) in diets of mussels and barnacles. • Also, oil did not enhance planktonic respiration rates. • Use of oil carbon was relatively small in these productive estuarine food webs. - Abstract: Natural abundance carbon isotope analyses are sensitive tracers for fates and use of oil in aquatic environments. Use of oil carbon in estuarine food webs should lead to isotope values approaching those of oil itself, −27‰ for stable carbon isotopes reflecting oil origins and −1000‰ for carbon-14 reflecting oil age. To test for transfer of oil from the 2010 Deepwater Horizon spill into estuarine food webs, filter-feeding barnacles (Balanus sp.) and marsh mussels (Geukensia demissa) were collected from Louisiana estuaries near the site of the oil spill. Carbon-14 analyses of these animals from open waters and oiled marshes showed that oil use was <1% and near detection limits estimated at 0.3% oil incorporation. Respiration studies showed no evidence for enhanced microbial activity in bay waters. Results are consistent with low dietary impacts of oil for filter feeders and little overall impact on respiration in the productive Louisiana estuarine systems

  1. A 2D fluid motion model of the estuarine water circulation: Physical analysis of the salinity stratification in the Sebou estuary

    Science.gov (United States)

    Haddout, Soufiane; Maslouhi, Abdellatif; Magrane, Bouchaib

    2018-02-01

    Estuaries, which are coastal bodies of water connecting the riverine and marine environment, are among the most important ecosystems in the world. Saltwater intrusion is the movement of coastal saline water into an estuary, which makes up-estuary water, that becomes salty due to the mixing of freshwater with saltwater. It has become a serious environmental problem in the Sebou estuary (Morocco) during wet and dry seasons, which have a considerable impact on residential water supply, agricultural water supply as well as urban industrial production. The variations of salt intrusion, and the vertical stratification under different river flow conditions in the Sebou estuary were investigated in this paper using a two-dimensional numerical model. The model was calibrated and verified against water level variation, and salinity variation during 2016, respectively. Additionally, the model validation process showed that the model results fit the observed data fairly well ( R2 > 0.85, NSC > 0.89 and RMSE = 0.26 m). Model results show that freshwater is a dominant influencing factor to the saltwater intrusion and controlled salinity structure, vertical stratification and length of the saltwater intrusion. Additionally, the extent of salinity intrusion depends on the balance between fresh water discharges and saltwater flow from the sea. This phenomenon can be reasonably predicted recurring to mathematical models supported by monitored data. These tools can be used to quantify how much fresh water is required to counterbalance salinity intrusion at the upstream water intakes.

  2. The relation between salinity and copper complexing capacity of natural estuarine waters and the uptake of dissolved 64Cu by Macoma balthica

    NARCIS (Netherlands)

    Absil, M.C.P.; Gerringa, L.J.A.; Wolterbeek, H.T.

    1993-01-01

    The radiotracer 64Cu was used to assess the influence of natural organic ligands on the bioavailability of copper. Biological availability of the 64Cu-complexes was measured by accumulation in the bivalve Macoma balthica. The experiments were carried out in April as well as in February with water

  3. Emission of carbon dioxide from a tropical estuarine system, Goa, India

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.; DileepKumar, M.; Manerikar, M.

    . An experimental study revealed that soil-water interaction could be an important controller of pCO sub(2) abundance in these estuarine waters. The calculation water-to-air average fluxes were 67 and 11 m mol m sup(-2) d sup(-1), respectively,. In SW monsoon due...

  4. Water SA

    African Journals Online (AJOL)

    This journal publishes refereed, original work in all branches of water science, technology, engineering and policy. This includes: water resource development; the hydrological cycle; surface hydrology; geohydrology, hydropedology and hydrometeorology; limnology; freshwater and estuarine ecology; salinisation; treatment ...

  5. Coastal and estuarine resources of Bangladesh: management and conservation issues

    Directory of Open Access Journals (Sweden)

    Abu Hena M. Kamal

    2009-07-01

    Full Text Available The coastal area of Bangladesh includes a number of bays into which different types of rivers empty, creating an estuarine ecosystem adjacent to the shore. The main estuarine systems are Brahmaputra-Megna (Gangetic delta, Karnaphuly, Matamuhuri, Bakkhali and Naf rivers, which are comprised of mangroves, salt marshes, seagrass, seaweeds, fisheries, coastal birds, animals, coral reefs, deltas, salt beds, minerals and sand dunes. The estuarine environment, which serves as feeding, breeding and nursery grounds for a variety of animals, varies according to the volume of discharge of the river and tidal range. It is highly productive in terms of nutrient input from different sources that promotes other living resources in the estuaries. Drought conditions exist during the winter months, i.e. November to February, and effective rainfall is confined to the monsoon period, i.e. May to June. Changes in salinity and turbidity depend on annual rainfall. The colour of most estuarine waters is tea brown or brown due to heavy outflows during the monsoon. The tidal mixing and riverine discharge governs the distribution of the hydrological parameters. The pH of these waters is reported to be slightly alkaline (>7.66 and dissolved oxygen (<6.0 mg/l shows an inverse relationship to temperature. Studies of plankton have indicated two periods of maximum abundance, i.e. February-March and August-September. The abundance of fish and shrimp larvae varies in number and composition with season. Many marine and freshwater species are available in various types of coastal brackish water, which depend on monsoonal activities and local environmental conditions.

  6. Evaluation of Perna perna (Linné, 1758 as a tool to monitoring trace metals contamination in estuarine and coastal waters of Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Francioni Eleine

    2004-01-01

    Full Text Available Perna perna was collected from several sites along the coast of Rio de Janeiro and analysed for the content of copper, zinc, cadmium and chromium. In spite of the observed concentration variability in organisms pertaining to the same population, statistical evaluation allowed metal level differentiation among regions and sites as well as between males and females. Differences in metal contents did not confirm expectations based on source strength and existing data on water concentration.

  7. Water Quality in Estuarine Wetland Restoration: An Examination of Dissolved Oxygen and Nutrients in the South Bay Salt Pond Restoration Project

    Science.gov (United States)

    Stein, S.; Nanus, L.

    2016-12-01

    The South Bay Salt Pond Restoration Project (SBSPRP) was established in 2003 from 15,100 acres of former Cargill salt harvesting ponds in the San Francisco Bay Area. Since then, the SBSPRP has utilized an adaptive management framework to restore the ponds with the goal of habitat restoration, public access, and flood protection as its guiding principles. The SBSPRP is the largest wetland restoration project on the West Coast and the complexity of the project is compounded by nearby land use, including wastewater facilities and urban development. The majority of previous water quality studies in the area have primarily focused on legacy pollutants, such as methylated mercury. For a selection of Alviso ponds with diverse management histories, the spatial and temporal variability of water quality parameters including dissolved oxygen (DO), nitrate (NO3), and ammonium (NH4) were examined during summer 2016. Two ponds (A21 and A17) are tidally controlled, with water entering and exiting the ponds based on changes in tide levels; these ponds also receive treated wastewater via Coyote Creek slough. Two other ponds (A3W and A8) are managed ponds, with elevated gates partially controlling the water level and no direct flow of wastewater entering these ponds. DO varied between 2.48-9.25 mg/L across all ponds, with significantly lower DO in tidal ponds (mean = 3.9 mg/L) compared with the managed ponds (mean = 6.7 mg/L). Nutrient concentrations also differed between the managed ponds and tidal ponds. 70% of samples in the managed ponds were below the detection limit of 0.81 µM NO3-N. NO3 concentrations in the tidal ponds, located closest to the wastewater facilities, ranged from 47.6 - 111.8 µM NO3-N; DO values were negatively correlated with both NO3 and NH4 in the tidal ponds. These results suggest that greater considerations for DO and other water quality parameters may be of use in future adaptive management strategies in the SBSPRP.

  8. Characteristics and landcover of estuarine boundaries: implications ...

    African Journals Online (AJOL)

    This study investigated whether the current lateral boundary for estuaries in South Africa, i.e. the estuarine functional zone (EFZ), includes all estuarine habitats. The EFZ covers 173 930 ha in 304 estuaries/outlets nationally. Field surveys and analysis of available aerial images showed that 82 (12 956.70 ha) of these ...

  9. The Virginia Institute of Marine Science Estuarine Observing System

    Science.gov (United States)

    Friedrichs, C.; Anderson, B.; Brasseur, L.; Brubaker, J.; Moore, K.; Nelson, T.; Reay, W.; Vandever, J.; Wright, D.

    2006-05-01

    The estuarine observing system centered at the Virginia Institute of Marine Science (VIMS) aims to provide real-time and archived data in the Lower Chesapeake Bay to help guide the management of natural resources, enable planning for extreme events, facilitate maritime operations, support military security, and advance science and education. The VIMS observing system consists of a growing network of buoy and platform mounted sensors providing data on water quality, currents, winds and waves. Funding has been provided by the Commonwealth of Virginia, the National Oceanic and Atmospheric Administration, the National Science Foundation, the Office of Naval Research, and the U.S. Coast Guard. This presentation will provide an overview of the VIMS estuarine observing system.

  10. Detection of somatic coliphages as indicators of faecal contamination in estuarine waters Detección de colifagos somáticos como indicadores de contaminación fecal en aguas estuarinas

    Directory of Open Access Journals (Sweden)

    S. S. Brezina

    2008-03-01

    Full Text Available The appearance of enteric disease outbreaks associated with the use of waters considered bacteriologically suitable, calls for the search of new and more precise indicators. Samples of estuarine water were collected in order to quantify E. coli and E. coli ATCC 13706 somatic coliphages and to compare the usefulness of the latter to detect faecal contamination when the concentration of traditional indicators is not quantifiable. Statistical analyses suggested the division of sampling sites into two groups: group I and group II, according to the minor or major level of faecal pollution respectively registered. In group II a high correlation between the coliphages and E. coli (r: 0.73 pLa aparición de brotes de enfermedades víricas entéricas asociadas al uso de aguas bacteriológicamente aptas impone la búsqueda de nuevos y más precisos indicadores de contaminación. Se recolectaron muestras de agua estuarina, donde se cuantificaron simultáneamente la bacteria E. coli y los colifagos somáticos de E. coli ATCC 13706, a fin de evaluar la utilidad de estos últimos para detectar contaminación fecal cuando la concentración de los indicadores tradicionales no es cuantificable. Los resultados estadísticos sugirieron la división de las estaciones de muestreo en dos grupos, I y II, de acuerdo con el menor o mayor nivel de contaminación fecal registrado, respectivamente. En el grupo II se detectó una alta correlación entre los recuentos de colifagos y de E. coli (r: 0,73 p<0,01. Asimismo, en este grupo la abundancia de E. coli siempre superó a la de colifagos. En el grupo I la correlación fue estadísticamente significativa (r: 0,55 p < 0,05, pero de mediana magnitud, los recuentos de colifagos superaron a los de E. coli, y éstos fueron detectados aun en ausencia de la bacteria. En conclusión, los colifagos somáticos de E. coli ATCC 13706 serían una herramienta accesoria en el diagnóstico del nivel de contaminación fecal de aguas

  11. Are Fukushima inhabitants about to go home?

    International Nuclear Information System (INIS)

    Chauveau, L.

    2015-01-01

    4 years after the Fukushima accident a part of the evacuated population will be allowed to go home in the areas where radioactive contamination has fallen below 20 mSv/year. About one third of the evacuated zone will remain inhabited on a long term perspective because of a radioactive contamination above 50 mSv/year. The Futaba and Okuma towns (7.500 and 11.000 inhabitants respectively before the accident) have been chosen to home radioactive waste and contaminated soils, they will never again be inhabited. A study has shown that only 0.6% of the food produced in the Fukushima region in 2014 contained an excess of radioactivity. The risk for the japanese population to be contaminated through food is then very low. (A.C.)

  12. Seasonal variation in antioxidative responses and acetylcholinesterase activity in Perna viridis in eastern oceanic and western estuarine waters of Hong Kong

    Science.gov (United States)

    Lau, P. S.; Wong, H. L.; Garrigues, Ph.

    2004-10-01

    A year-round study was conducted to assess the seasonal variations and potential influence of the riverine discharge from the Pearl River on biomarker responses in Hong Kong waters. A suite of biomarkers including antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), the lipid peroxidation product malondialdehyde (MDA), a Phase II detoxification enzyme glutathione-S-transferase (GST) and the neural transmitter enzyme acetylcholinesterase (AChE) in the green mussel, Perna viridis, were monitored from three coastal sites, Port Shelter, Tung Chung and Tai O, stretching from the east to the west of Hong Kong. Despite of the seasonal variations, the total protein profiles suggested that mussels from the three sites had a growth cycle that was in phase with each other. This implied that intrinsic variation between sites due to a different phase of growth was minimal. Seasonal variations of the biomarker responses in the mussels were found to be significant (Tukey multiple comparison test, pbiomarker responses at Tai O in relation to the extreme low salinity of 8‰. Mussels from the western site also revealed a higher oxidative stress than those from the eastern side throughout the year (Tukey multiple comparison test, pbiomarker responses. Gill tissues of the mussels were more advantageous for biomarker studies or monitoring because their protein levels were less sensitive to seasonal variations and they yielded a higher protein normalized biomarker response than the whole body tissues. This increases their discrimination ability for site comparisons. The feasibility of biomarker monitoring in areas of sub-lethal or low chemical contamination will also be discussed.

  13. Ecotoxicology of bromoacetic acid on estuarine phytoplankton.

    Science.gov (United States)

    Gordon, Ana R; Richardson, Tammi L; Pinckney, James L

    2015-11-01

    Bromoacetic acid is formed when effluent containing chlorine residuals react with humics in natural waters containing bromide. The objective of this research was to quantify the effects of bromoacetic acid on estuarine phytoplankton as a proxy for ecosystem productivity. Bioassays were used to measure the EC50 for growth in cultured species and natural marine communities. Growth inhibition was estimated by changes in chlorophyll a concentrations measured by fluorometry and HPLC. The EC50s for cultured Thalassiosira pseudonana were 194 mg L(-1), 240 mg L(-1) for Dunaliella tertiolecta and 209 mg L(-1) for Rhodomonas salina. Natural phytoplankton communities were more sensitive to contamination with an EC50 of 80 mg L(-1). Discriminant analysis suggested that bromoacetic acid additions cause an alteration of phytoplankton community structure with implications for higher trophic levels. A two-fold EC50 decrease in mixed natural phytoplankton populations affirms the importance of field confirmation for establishing water quality criteria. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Dual impact of temperature on growth and mortality of marine fish larvae in a shallow estuarine habitat

    Science.gov (United States)

    Arula, Timo; Laur, Kerli; Simm, Mart; Ojaveer, Henn

    2015-12-01

    High individual growth and mortality rates of herring Clupea harengus membras and goby Pomatoschistus spp. larvae were observed in the estuarine habitat of the Gulf of Riga, Baltic Sea. Both instantaneous mortality (0.76-1.05) as well as growth rate (0.41-0.82 mm day-1) of larval herring were amongst highest observed elsewhere previously. Mortality rates of goby larvae were also high (0.57-1.05), while first ever data on growth rates were provided in this study (0.23-0.35 mm day-1). Our study also evidenced that higher growth rate of marine fish larvae did not result in lower mortalities. We suggest that high growth and mortality rates primarily resulted from a rapidly increasing and high (>18 °C) water temperature that masked potential food-web effects. The explanation for observed patterns lies in the interactive manner temperature contributed: i) facilitating prey production, which supported high growth rate and decreased mortalities; ii) exceeding physiological thermal optimum of larvae, which resulted in decreased growth rate and generally high mortalities. Our investigation suggests that the projected climate warming may have significant effect on early life history stages of the dominating marine fish species inhabiting shallow estuaries.

  15. Diversity and composition of estuarine and lagoonal fish assemblages of Socotra Island, Yemen.

    Science.gov (United States)

    Lavergne, E; Zajonz, U; Krupp, F; Naseeb, F; Aideed, M S

    2016-05-01

    Estuarine and lagoonal surveys of Socotra Island and selected sites on the Hadhramout coast of Yemen were conducted with the objective of documenting and analysing fish diversity and assemblage structure. A total of 74 species in 35 families were recorded, among which 65 species in 32 families were from Socotra and 20 species in 17 families were from mainland Yemen. Twenty-one species represent new faunal records for Socotra. Including historic records re-examined in this study, the total fish species richness of estuaries and lagoons of Socotra Island reaches 76, which is relatively high compared to species inventories of well-researched coastal estuaries in southern Africa. Five species dominate the occurrence and abundance frequencies: Terapon jarbua, Hyporhamphus sindensis, Aphanius dispar, Ambassis gymnocephala and Chelon macrolepis. Rarefaction and extrapolation analyses suggest that the actual number of fish species inhabiting some of those estuaries might be higher than the one observed. Thus, additional sampling at specific sites should be conducted to record other less conspicuous species. Ordination and multivariate analyses identified four main distinct assemblage clusters. Two groups are geographically well structured and represent northern Socotra and mainland Yemen, respectively. The other two assemblage groups tend to be determined to a greater extent by the synchrony between physical (e.g. estuary opening periods) and biological (e.g. spawning and recruitment periods) variables than by geographical location. Finally, the single intertidal lagoon of Socotra represents by itself a specific fish assemblage. The high proportion of economically important fish species (38) recorded underscores the paramount importance of these coastal water bodies as nursery sites, and for sustaining vital provisioning ecosystem services. © 2016 The Fisheries Society of the British Isles.

  16. Meta-analysis of estuarine nurseries

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Densities of juvenile fishery species and other animals (all generally 100 mm total length) were summarized for shallow estuarine areas along coastal Texas and...

  17. Inhabiting compassion: A pastoral theological paradigm

    Directory of Open Access Journals (Sweden)

    Phil C. Zylla

    2017-08-01

    Full Text Available Inspired by the vision of care in Vincent van Gogh’s depiction of the parable of the Good Samaritan, this article offers a paradigm for inhabiting compassion. Compassion is understood in this article as a moral emotion that is also a pathocentric virtue. This definition creates a dynamic view of compassion as a desire to alleviate the suffering of others, the capacity to act on behalf of others and a commitment to sustain engagement with the suffering other. To weave this vision of compassion as a habitus rather than a theoretical construct, the article develops three phases of compassion: seeing, companioning and sighing. This framework deepens and augments a pastoral theological paradigm of compassion with the aim of inculcating an inhabited compassion in caregivers and the communities in which they participate.

  18. Microbial degradation of pharmaceuticals in estuarine and coastal seawater

    Energy Technology Data Exchange (ETDEWEB)

    Benotti, Mark J. [Marine Sciences Research Center, Stony Brook University, Stony Brook, NY 11794-5000 (United States); Brownawell, Bruce J. [Marine Sciences Research Center, Stony Brook University, Stony Brook, NY 11794-5000 (United States)], E-mail: bruce.brownawell@sunysb.edu

    2009-03-15

    Microbial degradation rates were measured for 19 pharmaceuticals in estuarine and coastal surface water samples. Antipyrine, carbamazepine, cotinine, sulfamethoxazole, and trimethoprim were the most refractory (half-lives, t{sub 1/2} = 35 to >100 days), making them excellent candidates for wastewater tracers. Nicotine, acetaminophen, and fluoxetine were labile across all treatments (t{sub 1/2} = 0.68-11 days). Caffeine, diltiazem, and nifedipine were also and relatively labile in all but one of the treatments (t{sub 1/2} = 3.5-13 days). Microbial degradation of caffeine was further confirmed by production {sup 14}CO{sub 2}. The fastest decay of non-refractory compounds was always observed in more sewage-affected Jamaica Bay waters. Degradation rates for the majority of these pharmaceuticals are much slower than reported rates for small biomolecules, such as glucose and amino acids. Batch sorption experiments indicate that removal of these soluble pharmaceuticals from the water column to sediments is a relatively insignificant removal process in these receiving waters. - Microbial degradation rates were measured for 19 structurally variable pharmaceuticals in wastewater-impacted estuarine and coastal seawater.

  19. Tributyltin-resistant bacteria from estuarine and freshwater sediments.

    OpenAIRE

    Wuertz, S; Miller, C E; Pfister, R M; Cooney, J J

    1991-01-01

    Resistance to tributyltin (TBT) was examined in populations from TBT-polluted sediments and nonpolluted sediments from an estuary and from fresh water as well as in pure cultures isolated from those sediments. The 50% effective concentrations (EC50s) for populations were higher at a TBT-polluted freshwater site than at a site without TBT, suggesting that TBT selected for a TBT-resistant population. In contrast, EC50s were significantly lower for populations from a TBT-contaminated estuarine s...

  20. Prevalence of Cryptosporidium Infection among Inhabitants of 2 Rural Areas in White Nile State, Sudan.

    Science.gov (United States)

    Sim, Seobo; Yu, Jae-Ran; Lee, Young-Ha; Lee, Jin-Su; Jeong, Hoo-Gn; Mohamed, Abd Al Wahab Saed; Hong, Sung-Tae

    2015-12-01

    Cryptosporidium , a protozoan parasite that causes watery diarrhea, is found worldwide and is common in areas with low water hygiene. In February 2014, 866 stool samples were collected from the inhabitants of 2 rural areas in White Nile State, Sudan. These stool samples were assessed by performing modified acid-fast staining, followed by examination under a light microscope. The overall positive rate of Cryptosporidium oocysts was 13.3%. Cryptosporidium oocysts were detected in 8.6% stool samples obtained from inhabitants living in the area having water purification systems and in 14.6% stool samples obtained from inhabitants living in the area not having water purification systems. No significant difference was observed in the prevalence of Cryptosporidium infection between men and women (14.7% and 14.1%, respectively). The positive rate of oocysts by age was the highest among inhabitants in their 60s (40.0%). These findings suggest that the use of water purification systems is important for preventing Cryptosporidium infection among inhabitants of these rural areas in Sudan.

  1. Three-dimensional semi-idealized model for estuarine turbidity maxima in tidally dominated estuaries

    NARCIS (Netherlands)

    Kumar, Mohit; Schuttelaars, Henk M.; Roos, Pieter C.

    2017-01-01

    We develop a three-dimensional idealized model that is specifically aimed at gaining insight in the physical mechanisms resulting in the formation of estuarine turbidity maxima in tidally dominated estuaries. First, the three-dimensional equations for water motion and suspended sediment

  2. Herbicides from the Charente river and the estuarine zone (Marennes-Oleron) to the coastal seawater

    International Nuclear Information System (INIS)

    Scribe, P.; Chouakri, S.; Dupas, S.

    1999-01-01

    Spatial distribution of herbicides was investigated in the fluvial section, the estuary of the Charente river and the coastal zone (Marennes-Oleron). Monthly samplings were performed on a fluvial section from Angouleme to Saintes, at Chalonne, Nersac, Sireuil, Bourg and Brives from 1993 onwards. Estuarine and coastal sea-waters were sampled during two cruises in May 1991 and February 1992

  3. Primary habitats of the St Lucia Estuarine System, South Africa, and ...

    African Journals Online (AJOL)

    Four primary habitats have been identified in the St Lucia estuarine system, each having a suite of characteristic vegetation types. These can be described as follows: (1) open water; (2) intertidal shoreline; (3) 'dry' shoreline and island (i.e. those habitats without any freshwater source other than rainfall); and (4) ...

  4. Role of salinity in structuring the intertidal meiofauna of a tropical estuarine beach: Field evidence

    Digital Repository Service at National Institute of Oceanography (India)

    Ingole, B.S.; Parulekar, A.H.

    Community structure of meiofauna was studied for 12 months (July 1991-June 1992) on an estuarine intertidal beach at Siridao, Goa (India). The temperature of the surf zone water ranged from 26.5 degrees to 30.7 degrees C; salinity from 8.3 to 34.4 x...

  5. The potential for a fish ladder to mitigate against the loss of marine-estuarine-freshwater connectivity in a subtropical coastal lake

    CSIR Research Space (South Africa)

    Weerts, Steven P

    2014-01-01

    Full Text Available Increasing water demand in coastal regions has resulted in the construction of weirs and barrages in coastal freshwaters. These form barriers to migrations of estuarine and euryhaline marine fishes and crustaceans. This study assessed the impact...

  6. Knowledge, attitudes and practices of local inhabitants about ...

    African Journals Online (AJOL)

    ITNs awareness level of inhabitants was 92.4%; however, just 57.8% of them own ITNs. 96.2% and 91.5% of the inhabitants indicated the foremost reasons for nonpossession of ITNs were due to unaffordability and nonavailability. Inhabitants average monthly income significantly associated with the ITNs ownership at p< ...

  7. Characteristics and landcover of estuarine boundaries: implications for the delineation of the South African estuarine functional zone

    CSIR Research Space (South Africa)

    Veldkornet, DA

    2015-11-01

    Full Text Available Zulu-Natal), cultivation has removed estuarine habitat. Although delineation of boundaries can be complicated by landcover changes, the estuarine lateral boundary in Cape estuaries could be identified based on sediment characteristics (moisture content, organic content...

  8. Brown, C.A., D. Sharp, and T. Mochon Collura. 2016. Effect of Climate Change on Water Temperature and Attainment of Water Temperature Criteria in the Yaquina Estuary, Oregon (USA). Estuarine, Coastal and Shelf Science. 169:136-146.

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset contains the research described in the following publication: Brown, C.A., D. Sharp, and T. Mochon Collura. 2016. Effect of Climate Change on Water...

  9. The negative role of turbulence in estuarine mass transport

    Science.gov (United States)

    Nunes Vaz, Richard A.; Lennon, Geoffrey W.; de Silva Samarasinghe, Jayantha R.

    1989-04-01

    It is competition between the various stratifying and mixing influences which determines the character of stratification in an estuary. Borrowing concepts which have been successfully applied to the discussion of stratification in shelf seas, a quantitative basis for determining the potential energy associated with vertical structure in estuaries is derived. The formulation, along similar lines to that of Bowden (1981), provides a simple but comprehensive method of incorporating many relevant stratifying and mixing influences in a given problem, and is also shown to be capable of rearrangement into forms akin to the estuarine Richardson number which is commonly found in discussions of estuarine statification. The paper argues, based on a survey of the literature, that in wide, relatively well-mixed estuaries, the greatest longitudinal mass flux occurs at times when stratification is most developed, that is, when the turbulent kinetic energy in the water column is at a minimum. Modulation of turbulence, principally at various tidal frequencies, causes a pulsing of the mass flux in which the contribution of each pulse increases non-linearly as the period of the modulation increases. Some, possibly significant, changes to the state of stratification and to the corresponding mass transport may occur in association with slack water periods. However, the spring-neap cycle is proposed to have a far greater influence on stratification, mass transport and the long-term mass balance in estuaries, and recent observational studies lend support to this position.

  10. Water SA: Editorial Policies

    African Journals Online (AJOL)

    Focus and Scope. This journal publishes refereed, original work in all branches of water science, technology, engineering and policy. This includes: water resource development; the hydrological cycle; surface hydrology; geohydrology, hydropedology and hydrometeorology; limnology; freshwater and estuarine ecology; ...

  11. Metal accumulation in earthworms inhabiting floodplain soils

    International Nuclear Information System (INIS)

    Vijver, Martina G.; Vink, Jos P.M.; Miermans, Cornelis J.H.; Gestel, Cornelis A.M. van

    2007-01-01

    The main factors contributing to variation in metal concentrations in earthworms inhabiting floodplain soils were investigated in three floodplains differing in inundation frequency and vegetation type. Metal concentrations in epigeic earthworms showed larger seasonal variations than endogeic earthworms. Variation in internal levels between sampling intervals were largest in earthworms from floodplain sites frequently inundated. High and low frequency flooding did not result in consistent changes in internal metal concentrations. Vegetation types of the floodplains did not affect metal levels in Lumbricus rubellus, except for internal Cd levels, which were positively related to the presence of organic litter. Internal levels of most essential metals were higher in spring. In general, no clear patterns in metal uptake were found and repetition of the sampling campaign will probably yield different results. - Metal levels in earthworms show large variation among sites, among seasons and among epigeic and endogeic species

  12. Long Term Ecological Research (LTER) Daily Estuarine Surface Water Nutrient and Water Quality, Suspended Sediment, and Chlorophyll a Data for the North Inlet Estuary, Georgetown, South Carolina: 1978-1993

    Data.gov (United States)

    Baruch Institute for Marine and Coastal Sciences, Univ of South Carolina — A one 1000 ml (one Liter) water sample was collected daily (at approximately 1000 hrs EST - but see note below in section 1.2.3 Supplemental Information) at a depth...

  13. Seasonal variability of estuarine dynamics due to freshwater discharge and its influence on biological productivity in Yeongsan River Estuary, Korea.

    Science.gov (United States)

    Kim, Yong Hoon; Hong, Seongjin; Song, Yong Sik; Lee, Hyojin; Kim, Hae-Cheol; Ryu, Jongseong; Park, Jinsoon; Kwon, Bong-Oh; Lee, Chang-Hee; Khim, Jong Seong

    2017-08-01

    In order to evaluate water quality and biological productivity, observation data sets were collected and analyzed in Yeongsan River Estuary, Korea. We also set up a numerical model to resolve hydrodynamics and fate of water quality variables in the system. Results show that most of nutrients loading are trapped in the lake and higher concentrations of nutrients and organic matters (OM) are present only inside of the artificial sea dike. There exist episodial discharges at the dam, which coincide mostly with rainfall events during summer monsoon periods. During this discharge event, lower salinity and higher suspended solids, nutrients, and OM are observed in surface layer of the estuarine section. Hydrodynamic model results show that circulation in the estuarine section is governed by freshwater discharge from the lake, resulting in an enhanced two-layer estuarine circulation being dominated, during and after the freshwater is discharged. Such two-layer estuarine circulation combined with higher concentration of nutrients in the surface layer results in that outfluxes of nutrients in the surface layer dominate over the influxes in the bottom layer during summer high precipitation periods. Meanwhile, numerical dye experiment results show that the discharged water with elevated nutrients levels have a short residence time (∼5-10 days) in the estuarine section. Due to this fast flushing rate, excessive nutrient loadings are not used to produce biological matters in the estuarine section. This limited biological productivity, characterized by seaward side of the artificial sea dike, makes Yeongsan estuarine system excluded from acting as an active carbon sink. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Conservation Priority Index for Estuarine Fish (COPIEF)

    Science.gov (United States)

    Branco, Paulo; Costa, José Lino; Raposo de Almeida, Pedro

    2008-12-01

    Public awareness regarding environmental issues has increased in recent decades. The increasing number of impact assessment studies, management and conservation plans, as well as ecological monitoring studies, demand new and more efficient techniques. Indices are an important tool to aid biologists in these studies and should allow an easier comprehension of the data by managers, decision-makers and the general public. This study presents the first multi-metrical index able to establish a hierarchical ordination of the conservation priority of the estuarine fish species using 72 species from 16 estuarine systems (W and S coasts of Portugal). The index is composed of 10 metrics, comprising species life traits, distribution and population trends. The information needed to score each metric was gathered from the published literature and the index validation was done by external means. This methodology allowed the definition of those fish species most in need of conservation planning, and those less prone to extinction in Portuguese estuarine systems. The proposed index fills a gap in our knowledge and provides a useful tool to the scientific community and to the decision-makers, being a breakthrough in the field of conservation planning of estuarine fish species.

  15. Growth Characteristics of an Estuarine Heterocystous Cyanobacterium

    NARCIS (Netherlands)

    Guimarães, P.; Yunes, J.S.; Cretoiu, M.S.; Stal, L.J.

    2017-01-01

    A new estuarine filamentous heterocystous cyanobacterium was isolated from intertidal sediment of the Lagoa dos Patos estuary (Brazil). The isolate may represent a new genus related to Cylindrospermopsis. While the latter is planktonic, contains gas vesicles, and is toxic, the newly isolated strain

  16. Joint Ecosystem Modeling (JEM) ecological model documentation volume 1: Estuarine prey fish biomass availability v1.0.0

    Science.gov (United States)

    Romañach, Stephanie S.; Conzelmann, Craig; Daugherty, Adam; Lorenz, Jerome L.; Hunnicutt, Christina; Mazzotti, Frank J.

    2011-01-01

    Estuarine fish serve as an important prey base in the Greater Everglades ecosystem for key fauna such as wading birds, crocodiles, alligators, and piscivorous fishes. Human-made changes to freshwater flow across the Greater Everglades have resulted in less freshwater flow into the fringing estuaries and coasts. These changes in freshwater input have altered salinity patterns and negatively affected primary production of the estuarine fish prey base. Planned restoration projects should affect salinity and water depth both spatially and temporally and result in an increase in appropriate water conditions in areas occupied by estuarine fish. To assist in restoration planning, an ecological model of estuarine prey fish biomass availability was developed as an evaluation tool to aid in the determination of acceptable ranges of salinity and water depth. Comparisons of model output to field data indicate that the model accurately predicts prey biomass in the estuarine regions of the model domain. This model can be used to compare alternative restoration plans and select those that provide suitable conditions.

  17. Geochronology of the Rio Formoso estuarine by {sup 210}Pb

    Energy Technology Data Exchange (ETDEWEB)

    Arruda, Gilberto N.; Lyra, Denilson T.; Melo, Julyanne T.B.; Farias, Emerson E.G.; Franca, Elvis J.; Santos, Thiago O., E-mail: gnarruda@cnen.gov.br, E-mail: denilsonengseg@gmail.com, E-mail: julyanne.melo@ufpe.br, E-mail: emersonemiliano@yahoo.com.br, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Souza Neto, Joao A., E-mail: adauto@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2015-07-01

    Uranium series disequilibrium is useful for dating methods, in which profile sediments can be considered as historical records of anthropogenic events regarding the distribution and impacts of chemical substances on the environment. In this study, 2 deep sediment profiles (about 1 m) were collected, layered at each 3 cm, oven-dried and homogenized. The radiochemical separation of {sup 210}Pb consisted of using hydrobromic acid and an ion exchange resin (DOWEX) for precipitating {sup 210}Pb in the form of lead chromate. After 10 days, the radioactivity was therefore measured by means of the low level gas flow proportional counter, model S5-XLB, from Canberra. Sedimentation rate were obtained by CIC (Constant Initial Concentration) model assumes a constant sedimentation rate throughout the period over which unsupported {sup 210}Pb is measurable. Some sediment profiles were not dated since the percentage of sand was quite high in top layers or a high percentage of organic matter and water in excess were observed in the all sediment samples. {sup 210}Pb geochronology was successfully applied to age nine sediment profiles, in which higher sedimentation rates were observed in the middle portion of the estuarine probably related to shrimp farming impacts. By using geochronology, the detection of human impacts on chemical element distribution could be enhanced in the case of environmental monitoring studies in the Rio Formoso estuarine. (author)

  18. Geochronology of the Rio Formoso estuarine by 210Pb

    International Nuclear Information System (INIS)

    Arruda, Gilberto N.; Lyra, Denilson T.; Melo, Julyanne T.B.; Farias, Emerson E.G.; Franca, Elvis J.; Santos, Thiago O.; Souza Neto, Joao A.

    2015-01-01

    Uranium series disequilibrium is useful for dating methods, in which profile sediments can be considered as historical records of anthropogenic events regarding the distribution and impacts of chemical substances on the environment. In this study, 2 deep sediment profiles (about 1 m) were collected, layered at each 3 cm, oven-dried and homogenized. The radiochemical separation of 210 Pb consisted of using hydrobromic acid and an ion exchange resin (DOWEX) for precipitating 210 Pb in the form of lead chromate. After 10 days, the radioactivity was therefore measured by means of the low level gas flow proportional counter, model S5-XLB, from Canberra. Sedimentation rate were obtained by CIC (Constant Initial Concentration) model assumes a constant sedimentation rate throughout the period over which unsupported 210 Pb is measurable. Some sediment profiles were not dated since the percentage of sand was quite high in top layers or a high percentage of organic matter and water in excess were observed in the all sediment samples. 210 Pb geochronology was successfully applied to age nine sediment profiles, in which higher sedimentation rates were observed in the middle portion of the estuarine probably related to shrimp farming impacts. By using geochronology, the detection of human impacts on chemical element distribution could be enhanced in the case of environmental monitoring studies in the Rio Formoso estuarine. (author)

  19. Hydrologic influence on redox dynamics in estuarine environments

    Science.gov (United States)

    Michael, H. A.; Kim, K. H.; Guimond, J. A.; Heiss, J.; Ullman, W. J.; Seyfferth, A.

    2017-12-01

    Redox conditions in coastal aquifers control reactions that impact nutrient cycling, contaminant release, and carbon budgets, with implications for water resources and ecosystem health. Hydrologic changes can shift redox boundaries and inputs of reactants, especially in dynamic coastal systems subject to fluctuations on tidal, lunar, and longer timescales. We present two examples of redox shifts in estuarine systems in Delaware, USA: a beach aquifer and a saltmarsh. Beach aquifers are biogeochemical hot spots due to mixing between fresh groundwater and infiltrating seawater. At Cape Henlopen, DE, geochemical measurements identified reactions in the intertidal aquifer that include cycling of carbon, nitrogen, iron, and sulfur. Measurements and modeling illustrate that redox potential as well as the locations of redox reactions shift on tidal to seasonal timescales and in response to changing beach and aquifer properties, impacting overall rates of reactions such as denitrification that reduces N loads to coastal waters. In the St. Jones National Estuarine Research Reserve, tidal fluctuations in channels cause periodic groundwater-surface water exchange, water table movement, and intermittent flooding that varies spatially across the saltmarsh. These changes create shifts in redox potential that are greatest near channels and in the top 20 cm of sediments. The magnitude of redox change depends on hydrologic setting (near channels or in marsh interior), hydrologic conditions (tidal stage, seasonal shifts), as well as prevalence of macropores created by crab burrows that change seasonally with crab activity. These shifts correspond to changes in porewater chemistry that have implications for nutrient cycling and carbon export to the ocean. Understanding hydrologic influence on redox geochemistry is critical for predicting how these systems and their ecosystem services may change in the future in response to anthropogenic and climate change.

  20. SUICIDAL ATTEMPTS AMONG YOUNG RURAL INHABITANTS

    Directory of Open Access Journals (Sweden)

    Zdzisław Brzeski

    2010-06-01

    Full Text Available In recent years changes have been noted in the motivations for acute suicidal poisonings among young people from various environments, which are due to psychosocial changes both in the urban and rural environments. Suicidal attempts are accompanied – especially in the rural environment – by low social status, difficulties with adapting to a free market economy, emotional tension within the family, at school, in the environment of young people, addiction to alcohol, drug overuse, including psychotropes. Based on clinical material concerning rural inhabitants hospitalized due to suicidal poisonings, the authors performed the analysis of attitudes, motivations and causes of acute poisonings among the young rural population. Among rural adolescents who continued school or university education the dominant causes of undertaking a suicidal attempt were: adolescent period problems, conflicts within the family, conflicts with mates, and disappointment in love. Among young adults the motivations were as follows: difficulties with finding employment in the place of residence, conflicts within the family, overuse of stimulants, and sometimes states of depression during the period of aggravation of a disease.

  1. An assessment of landscape characteristics affecting estuarine nitrogen loading in an urban watershed.

    Science.gov (United States)

    Yang, Xiaojun

    2012-02-01

    Exploring the quantitative association between landscape characteristics and the ecological conditions of receiving waters has recently become an emerging area for eco-environmental research. While the landscape-water relationship research has largely targeted on inland aquatic systems, there has been an increasing need to develop methods and techniques that can better work with coastal and estuarine ecosystems. In this paper, we present a geospatial approach to examine the quantitative relationship between landscape characteristics and estuarine nitrogen loading in an urban watershed. The case study site is in the Pensacola estuarine drainage area, home of the city of Pensacola, Florida, USA, where vigorous urban sprawling has prompted growing concerns on the estuarine ecological health. Central to this research is a remote sensor image that has been used to extract land use/cover information and derive landscape metrics. Several significant landscape metrics are selected and spatially linked with the nitrogen loading data for the Pensacola bay area. Landscape metrics and nitrogen loading are summarized by equal overland flow-length rings, and their association is examined by using multivariate statistical analysis. And a stepwise model-building protocol is used for regression designs to help identify significant variables that can explain much of the variance in the nitrogen loading dataset. It is found that using landscape composition or spatial configuration alone can explain most of the nitrogen loading variability. Of all the regression models using metrics derived from a single land use/cover class as the independent variables, the one from the low density urban gives the highest adjusted R-square score, suggesting the impact of the watershed-wide urban sprawl upon this sensitive estuarine ecosystem. Measures towards the reduction of non-point source pollution from urban development are necessary in the area to protect the Pensacola bay ecosystem and its

  2. The Fate of Contaminants and Stable Pb Isotopes in a Changing Estuarine Environment: 20 Years On.

    Science.gov (United States)

    Cundy, Andrew B; Croudace, Ian W

    2017-09-05

    Estuarine sediments provide an important sink for contaminants discharged into fluvial, estuarine, and nearshore settings, and numerous authors have utilized this trapping function to assess historical contaminant loadings and contaminant breakdown/transformation processes. This Article examines the retention of elemental and isotopic sedimentary signatures in an industrialized estuarine system subject to a strongly upward sea-level trend, over a 20 year period. Two contrasting saltmarsh sites (at Hythe and Hamble, part of the wider Southampton Water estuarine system, UK) were examined, which had been previously cored and analyzed in the early 1990s. Much of the geochemical record of recent anthropogenic activity has been eroded and lost at the Hamble site. In contrast, radiometric, isotopic and elemental records of anthropogenic activity have been retained in the Hythe marsh, with 137 Cs and Cu depth profiles showing retention of input maxima related to fallout and local industrial discharges, respectively. Stable Pb isotope data show a broad degree of correspondence in cores analyzed in 1994 and 2014 when plotted against sediment (radiometric) age, indicating the usefulness of isotopic data in retaining information on Pb sources and in disentangling Pb input histories. New ultrahigh precision, double-spike mass spectrometry stable Pb isotope data allow clearer discrimination of historical Pb input phases, and highlight within-estuary mixing and supply of reworked, secondary contamination from erosion of anthropogenically labeled sediments elsewhere in the estuary.

  3. Modelling the effect of hydrological change on estuarine health: An Australian Perspective. (Invited)

    Science.gov (United States)

    Bruce, L. C.; Adiyanti, S.; Ruibal, A. L.; Hipsey, M. R.

    2013-12-01

    Estuaries provide an important role in the filtering and transformation of carbon and nutrients from coastal catchments into the marine environment. Global trends including climate change, increased population, industrialization and agriculture have led to the rapid deterioration of estuarine ecosystems across the world. Within the Australian context, a particular concern is how changes to hydrological regimes, due to both water diversions and climate variability, are contributing to increased stress and consequent decline in estuarine health. In this study we report the modeling output of five Australian estuaries, each with different hydrological regimes and alternative management issues relating to altered hydrology: 1) The Yarra River estuary is a highly urbanized system, also receiving agriculturally derived nutrients, where the concern is the role of periodic hypoxia in reducing the assimilation capacity of nitrogen and thus increased risk of algal blooms forming in the coastal environment; 2) The upper Swan River estuary in Western Australia, which experiences persistent anoxia and hypoxia brought about by reduced flows has led to the commissioning of several oxygenation plants to alleviate stress on biodiversity and overall estuarine health; 3) The health of the Caboolture estuary in Queensland has deteriorated in the past decade with the aim of model development to quantify the various sources of surface and groundwater derived nutrients; 4) The construction of an additional channel to increase flushing in the Peel Harvey estuary in Western Australia was designed to control persistent harmful algal blooms; and 5) The Lower River Murray estuary experienced a prolonged drought that led to the development of acid sulfate soils and acid drainage deteriorating water quality. For these applications we applied 3-D hydrodynamic-biogeochemical models to determine underlying relationships between altered flow regimes, increased temperatures and the response of

  4. Radon in groundwater and dose estimation for inhabitants in spas of the Sudety Mountains area, Poland

    International Nuclear Information System (INIS)

    Kozlowska, B.; Walencik, A.; Dorda, J.; Zipper, W.

    2008-01-01

    Full text: The highest average radon concentrations in water are found in the Sudety mountains area, located in the south-western part of Poland. This region is known for its beautiful hiking routes, clean environment and also a large number of natural water springs. Some of underground waters with mineralization of more than 1 g/l are mineral waters. Others contain elements with specific medicinal properties and they are called medicinal waters. Among them are radon enriched waters with radon activity equal to at least 74 Bq/l. Waters chosen for investigations were collected in 24 health resorts and towns of the Sudety mountains. Water samples were periodically collected from 118 springs over a period of 10 years. Most of these waters are mineral medicinal waters and are used for treatment for patients and tourists. 16 intakes are treated by inhabitants as drinking water for everyday use. Among them, 6 intakes are used in water supply systems for several buildings in some spas. The goal of our study was to determine the activity concentration of radon in underground spring water consumed by inhabitants and tourists and to calculate annual effective doses due to this radionuclide consumption and inhalation. Measurements of radon were performed with the use of the liquid scintillation technique

  5. Inputs and distributions of synthetic musk fragrances in an estuarine and coastal environment; a case study

    International Nuclear Information System (INIS)

    Sumner, Nicola R.; Guitart, Carlos; Fuentes, Gustavo; Readman, James W.

    2010-01-01

    Synthetic musks are ubiquitous contaminants in the environment. Compartmental distributions (dissolved, suspended particle associated and sedimentary) of the compounds throughout an axial estuarine transect and in coastal waters are reported. High concentrations of Galaxolide (HHCB) and Tonalide (AHTN) (987-2098 ng/L and 55-159 ng/L, respectively) were encountered in final effluent samples from sewage treatment plants (STPs) discharging into the Tamar and Plym Estuaries (UK), with lower concentrations of Celestolide (ADBI) (4-13 ng/L), Phantolide (AHMI) (6-9 ng/L), musk xylene (MX) (4-7 ng/L) and musk ketone (MK) (18-30 ng/L). Rapid dilution from the outfalls is demonstrated with resulting concentrations of HHCB spanning from 5 to 30 ng/L and those for AHTN from 3 to 15 ng/L. The other musks were generally not detected in the estuarine and coastal waters. The suspended particulate matter (SPM) and sedimentary profiles and compositions (HHCB:AHTN ratios) generally reflect the distribution in the water column with highest concentrations adjacent to sewage outfalls. - Synthetic musks were determined in coastal environmental compartments along an estuarine transect indicating their ubiquitous occurrence in transitional waters.

  6. 90Sr in fish inhabiting Ignalina NPP water cooling pond

    International Nuclear Information System (INIS)

    Dushauskiene - Duzh, R.

    1997-01-01

    The scope of this research was to investigate the way of the accumulation of 90 Sr in the tissues of fishes in the lake Drukshiai -cooling pond of Ignalina NPP, definition of its concentration and specificity of distribution . Research was carried out during 1994 - 1995. It was determined that the 90 Sr level in fish tissues and organs were formed by absorption and adsorption processes. More active were 90 Sr adsorption processes. 90 Sr concentration in skin with scales and gills reached 11.6±4.6 and 9.4±3.9 Bq/kg, respectively, while in fish organs and tissues it fluctuated from 1.2±0.35 (muscles) to 9.6±4.1 Bq/kg (digestion tract). The obtained data indicate that age, size and Ca concentration in fish are the main factors controlling the 90 Sr accumulation level in them. (author). 14 refs., 4 figs

  7. Reverse Estuarine Circulation Due to Local and Remote Wind Forcing, Enhanced by the Presence of Along-Coast Estuaries

    Science.gov (United States)

    Giddings, S. N.; MacCready, P.

    2017-12-01

    their important functionality. Understanding estuarine dynamics is critical to understanding estuarine ecosystems. Hydrodynamic connectivity between estuaries and the coastal ocean is a key dynamical driver impacting critical biological and biogeochemical processes such as ocean/estuarine nutrient and phytoplankton exchange and regulation of estuarine residence time, dissolved oxygen, and acidification levels. Typically estuarine-ocean exchange brings oceanic water into the estuary at depth, mixes it upwards within the estuary, and returns an outflowing mixture of oceanic and riverine water at the surface to the ocean. This manuscript documents seasonal reversals to this typical circulation pattern and the hydrodynamic drivers of the reversals. It highlights the importance of offshore winds and connectivity with neighboring estuaries. Improved understanding of these mechanisms can help us predict how estuaries will respond to a changing climate.

  8. Tufted Puffins nesting in estuarine habitat

    Science.gov (United States)

    Gill, Robert E.; Sanger, Gerald A.

    1979-01-01

    The Tufted Puffin (Lunda cirrhata) apparently has the most extensive breeding distribution of any North Pacific seabird, extending in the western North Pacific from Hokkaido to the north Chukotsk Peninsula on the Chukchi Sea, and in North America from Cape Lisburne on the Chukchi Sea, south to the Farallon Islands off central California (Udvardy 1963). Despite this wide breeding distribution, the reported nesting habitat is generally restricted to steep, rocky islands and continental headlands (see Dement’ev and Gladkov 1951, Kozlova 1957, Gabrielson and Lincoln 1959, Portenko 1973, Sealy 1973, and Sowls et al. 1978). Nests are typically excavated in steep slopes and/or on vegetated plateaus, well above normal tidal influence but occasionally within the spray or storm-wash zone. Nowhere has L. cirrhata or any other puffin species been reported to nest in a flat, estuarine habitat in substrate normally affected by tides during the breeding season. Portenko (1973: 137) refers to Tufted Puffins breeding on Alyumka Island in the Anadyr "estuary" (64°40'N, 177°37'E), but Alyumka Island is a rocky coastal island having immediate offshore waters between 3-18 m deep (A.A. Kistchinski, The Ringing Center, Moscow, and George Tyner, U.S. Defense Mapping Agency, pers. comm.).During the summers of 1976, 1977, and 1978, we found 14-18 pairs of Tufted Puffins nesting on 4 narrow sand islands (5-7 ha each) along the northcentral Alaska Peninsula at Nelson Lagoon (56°00'N, 161°10'W). As of June 1979, 25 active burrows had been reported there (Margaret R. Petersen, pers. comm.). The islands lie approximately 1.3 km from the Bering Sea coast and are protected from the sea by a long, narrow (0.5 kin) sand peninsula. The main deepwater channel in the lagoon, 3-7 m deep and 100-300 m wide at mean low water (MLW), separates the islands from the peninsula. The islands, which are free of permafrost, have a uniformly low profile with the highest elevation 1-2 m above mean high water

  9. Shock, stress or signal? Implications of freshwater flows for a top-level estuarine predator.

    Directory of Open Access Journals (Sweden)

    Matthew D Taylor

    Full Text Available Physicochemical variability in estuarine systems plays an important role in estuarine processes and in the lifecycles of estuarine organisms. In particular, seasonality of freshwater inflow to estuaries may be important in various aspects of fish lifecycles. This study aimed to further understand these relationships by studying the movements of a top-level estuarine predator in response to physicochemical variability in a large, temperate south-east Australian estuary (Shoalhaven River. Mulloway (Argyrosomus japonicus, 47-89 cm total length were surgically implanted with acoustic transmitters, and their movements and migrations monitored over two years via fixed-position VR2W acoustic receivers configured in a linear array along the length of the estuary. The study period included a high degree of abiotic variability, with multiple pulses (exponentially high flows over a short period of time in fresh water to the estuary, as well as broader seasonal variation in flow, temperature and conductivity. The relative deviation of fish from their modal location in the estuary was affected primarily by changes in conductivity, and smaller fish (n = 4 tended to deviate much further downstream from their modal position in the estuary than larger fish (n = 8. High-flow events which coincided with warmer temperatures tended to drive mature fish down the estuary and potentially provided a spawning signal to stimulate aggregation of adults near the estuary mouth; however, this relationship requires further investigation. These findings indicate that pulse and press effects of freshwater inflow and associated physicochemical variability play a role in the movements of mulloway, and that seasonality of large freshwater flows may be important in spawning. The possible implications of river regulation and the extraction of freshwater for consumptive uses on estuarine fishes are discussed.

  10. Shifts in the metabolic function of a benthic estuarine microbial community following a single pulse exposure to silver nanoparticles

    International Nuclear Information System (INIS)

    Echavarri-Bravo, Virginia; Paterson, Lynn; Aspray, Thomas J.; Porter, Joanne S.; Winson, Michael K.; Thornton, Barry; Hartl, Mark G.J.

    2015-01-01

    The increasing use of silver nanoparticles (AgNPs) as a biocidal agent and their potential accumulation in sediments may threaten non-target natural environmental bacterial communities. In this study a microcosm approach was established to investigate the effects of well characterized OECD AgNPs (NM-300) on the function of the bacterial community inhabiting marine estuarine sediments (salinity 31‰). The results showed that a single pulse of NM-300 AgNPs (1 mg L −1 ) that led to sediment concentrations below 6 mg Ag kg −1 dry weight inhibited the bacterial utilization of environmentally relevant carbon substrates. As a result, the functional diversity changed, but recovered after 120 h under the experimental conditions. This microcosm study suggests that AgNPs under environmentally relevant experimental conditions can negatively affect bacterial function and provides an insight into the understanding of the bacterial community response and resilience to AgNPs exposure, important for informing relevant regulatory measures. - Highlights: • AgNPs affected the bacterial community function in estuarine marine sediments. • AgNPs inhibited the bacterial utilization of environmentally relevant substrates. • Heterotrophic bacterial groups showed resilience to AgNPs after 120 h exposure. • AgNPs did not affect the bacterial community structure in sediments. - AgNPs inhibited the bacterial utilization of environmentally relevant substrates and caused temporary shifts in the bacterial functional diversity in marine estuarine sediments

  11. Partitioning of metals in different binding phases of tropical estuarine sediments: importance of metal chemistry

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, P.; Chakraborty, S.; Vudamala, K.; Sarkar, Arindam; Nath, B.N.

    binding phases of tropical estuarine sediments. Materials and Methods: Study area: The sediment samples were collected from the Vembanad Lake in Kerala, west coast of India. It is the longest (stretching about 90 km) and largest brackish-water lake... of the European Communities. International journal of environmental analytical chemistry, 51(1-4), 135-151. Verma, A., & Subramanian, V. (2002). Organic matter and amino acid concentrations in surface sediments of Vembanad Lake–a tropical estuary, west coast...

  12. Abiotic characteristics and microalgal dynamics in South Africa's largest estuarine lake during a wet to dry transitional phase

    Science.gov (United States)

    Nunes, Monique; Adams, Janine B.; Bate, Guy C.; Bornman, Thomas G.

    2017-11-01

    The summer of 2012/2013 signified the end of the dry phase in the St Lucia estuarine system that lasted for over a decade. The increased rainfall coupled with the partial re-connection of the Mfolozi River to the estuarine system shifted St Lucia to a new limnetic state. With the increased availability of habitat due to the higher water level, it was expected that microalgal biomass and abundance would rapidly increase through recruitment from refuge areas i.e. South Lake and new introductions. Microalgal and physico-chemical data were collected at three sites within the Mfolozi/Msunduzi River and at 23 sites within the St Lucia estuarine system between June 2014 and February 2015. Results from this study indicated low biomass for both phytoplankton (state.

  13. Management options for restoring estuarine dynamics and implications for ecosystems: a quantitative approach for the Southwest Delta in the Netherlands

    NARCIS (Netherlands)

    Ysebaert, T.; van der Hoek, D.-J.; Wortelboer, R.; Wijsman, J.W.M.; Tangelder, M.; Nolte, A.

    2016-01-01

    The Delta Works, a series of dams and barriers constructed in the 1960's–1980's changed the estuarine landscape of the Rhine-Meuse-Scheldt delta (SW Netherlands) into more stagnant and disengaged freshwater, brackish water or saltwater lakes. The remaining tidal systems were adapted by building a

  14. Accumulation of organochlorines and brominated flame retardants in estuarine and marine food chains : Field measurements and model calculations

    NARCIS (Netherlands)

    Veltman, Karin; Hendriks, Jan; Huijbregts, Mark; Leonards, Pim; Van Den Heuvel-Greve, Martine; Vethaak, Dick

    2005-01-01

    Food chain accumulation of organochlorines and brominated flame retardants in estuarine and marine environments is compared to model estimations and fresh water field data. The food chain consists of herbivores, detritivores and primary and secondary carnivores i.e. fish, fish-eating birds and

  15. Accumulation of organochlorines and brominated flame retardants in estuarine and marine food chains: Field measurements and model calculations

    NARCIS (Netherlands)

    Veltman, K.; Hendriks, J.; Huijbregts, M.; Leonards, P.E.G.; Heuvel-Greve, van den M.J.; Vethaak, D.

    2005-01-01

    Food chain accumulation of organochlorines and brominated flame retardants in estuarine and marine environments is compared to model estimations and fresh water field data. The food chain consists of herbivores, detritivores and primary and secondary carnivores i.e. fish, fish-eating birds and

  16. Ecoengineering with Ecohydrology: Successes and failures in estuarine restoration

    Science.gov (United States)

    Elliott, Michael; Mander, Lucas; Mazik, Krysia; Simenstad, Charles; Valesini, Fiona; Whitfield, Alan; Wolanski, Eric

    2016-07-01

    Ecological Engineering (or Ecoengineering) is increasingly used in estuaries to re-create and restore ecosystems degraded by human activities, including reduced water flow or land poldered for agricultural use. Here we focus on ecosystem recolonization by the biota and their functioning and we separate Type A Ecoengineering where the physico-chemical structure is modified on the basis that ecological structure and functioning will then follow, and Type B Ecoengineering where the biota are engineered directly such as through restocking or replanting. Modifying the physical system to create and restore natural processes and habitats relies on successfully applying Ecohydrology, where suitable physical conditions, especially hydrography and sedimentology, are created to recover estuarine ecology by natural or human-mediated colonisation of primary producers and consumers, or habitat creation. This successional process then allows wading birds and fish to reoccupy the rehabilitated areas, thus restoring the natural food web and recreating nursery areas for aquatic biota. We describe Ecohydrology principles applied during Ecoengineering restoration projects in Europe, Australia, Asia, South Africa and North America. These show some successful and sustainable approaches but also others that were less than successful and not sustainable despite the best of intentions (and which may even have harmed the ecology). Some schemes may be 'good for the ecologists', as conservationists consider it successful that at least some habitat was created, albeit in the short-term, but arguably did little for the overall ecology of the area in space or time. We indicate the trade-offs between the short- and long-term value of restored and created ecosystems, the success at developing natural structure and functioning in disturbed estuaries, the role of this in estuarine and wetland management, and the costs and benefits of Ecoengineering to the socio-ecological system. These global case

  17. Holocene estuarine sediments as a source of arsenic in Pleistocene groundwater in suburbs of Hanoi, Vietnam

    Science.gov (United States)

    Kuroda, Keisuke; Hayashi, Takeshi; Funabiki, Ayako; Do, An Thuan; Canh, Vu Duc; Nga, Tran Thi Viet; Takizawa, Satoshi

    2017-06-01

    Groundwater pollution by arsenic is a major health threat in suburban areas of Hanoi, Vietnam. The present study evaluates the effect of the sedimentary environments of the Pleistocene and Holocene deposits, and the recharge systems, on the groundwater arsenic pollution in Hanoi suburbs distant from the Red River. At two study sites (Linh Dam and Tai Mo communes), undisturbed soil cores identified a Pleistocene confined aquifer (PCA) and Holocene unconfined aquifer (HUA) as major aquifers, and Holocene estuarine and deltaic sediments as an aquitard layer between the two aquifers. The Holocene estuarine sediments (approximately 25-40 m depth, 9.6-4.8 cal ka BP) contained notably high concentrations of arsenic and organic matter, both likely to have been accumulated by mangroves during the Holocene sea-level highstand. The pore waters in these particular sediments exhibited elevated levels of arsenic and dissolved organic carbon. Arsenic in groundwater was higher in the PCA (25-94 μg/L) than in the HUA (5.2-42 μg/L), in both the monitoring wells and neighboring household tubewells. Elevated arsenic concentration in the PCA groundwater was likely due to vertical infiltration through the arsenic-rich and organic-matter-rich overlying Holocene estuarine sediments, caused by massive groundwater abstraction from the PCA. Countermeasures to prevent arsenic pollution of the PCA groundwater may include seeking alternative water resources, reducing water consumption, and/or appropriate choice of aquifers for groundwater supply.

  18. Estuarine consumers utilize marine, estuarine and terrestrial organic matter and provide connectivity among these food webs

    Science.gov (United States)

    The flux of organic matter (OM) across ecosystem boundaries can influence estuarine food web dynamics and productivity. However, this process is seldom investigated taking into account all the adjacent ecosystems (e.g. ocean, river, land) and different hydrological settings (i.e....

  19. The role of estuarine type in characterizing early stage fish ...

    African Journals Online (AJOL)

    Assemblages of early stage fishes (larval and early juvenile stages) were investigated and compared in seven permanently open and five intermittently open estuarine systems on the warm temperate Eastern Cape coast of South Africa. Estuarine type, by virtue of mouth state and prevailing physico chemical conditions, ...

  20. Comparative evaluation of effects of ozonated and chlorinated thermal discharges on estuarine and freshwater organisms

    Energy Technology Data Exchange (ETDEWEB)

    Guerra, C.R.; Sugam, R.; Meldrim, J.W.; Holmstrom, E.R.; Balog, G.E.

    1980-08-01

    As a part of a program at PSE and G designed to examine the feasibility of ozonation as an alternative to chlorination for control of biofouling in once-through cooling systems, the biological effects of ozonated and chlorinated thermal discharges were evaluated with estuarine and freshwater organisms. Mortality at salinities between 0.5 to 2.5 ppt with mummichog and white perch indicated greater toxicity for chlorine while the alewife, spottail shiner, rainbow trout and white perch in freshwater were more sensitive to ozone. Behavioral and physograhic results were consistent with those observed in toxicity studies. Initial cough response and avoidance concentrations of mummicog and white perch in estuarine waters were lower when exposed to chlorine than to ozone. In freshwater, blueback herring, alewife, rainbow trout, spottail shiner, banded killifish, and white perch avoided lower concentrations of ozone than chlorine.

  1. DISEÑO CONCEPTUAL DE UNA ESTACIÓN EXPERIMENTAL DE TRATAMIENTO DE AGUAS RESIDUALES DOMÉSTICAS ORIENTADA A MUNICIPIOS CON POBLACIÓN MENOR A 30.000 HABITANTES CONCEPTUAL DESIGN OF AN EXPERIMENTAL HOUSEHOLD WASTE WATER TREATMENT PLANT ADDRESSED TO MUNICIPALITIES WITH A POPULATION LOWER THAN 30,000 INHABITANTS

    Directory of Open Access Journals (Sweden)

    José Luis González Manosalva

    2012-12-01

    Full Text Available Se presenta el diseño conceptual de una planta experimental de tratamiento de aguas residuales para poblaciones menores de 30.000 habitantes. El diseño integra seis esquemas de tratamiento interconectados, incluyendo sistemas convencionales y no convencionales, con disposición final del efluente a un cuerpo de agua o infiltración lenta en el terreno, cumpliendo con la norma vigente en Colombia. El proceso incluyó una revisión del estado del arte, el diseño de plantas de este tipo como la planta de Carrión de los Céspedes (Andalucía-España, la planta UFMG/COPASA (Minas Gerais-Brasil, los trabajos realizados en Colombia del IDEAM-CINARA-UTP y los ensayos realizados por Madera, Silva y Peña del CINARA en planta piloto. El área estimada para la construcción de los esquemas propuestos es de 18.000 m² y los costos fijos de construcción de la planta se estiman en 850 millones de pesos para tratar un caudal de 1,5 l/s de agua residual doméstica.Conceptual design of an experimental waste water treatment plant for populations lower than 30,000 inhabitants is presented. The design integrates six interconnected treatment systems, including conventional and non-conventional systems with final disposal of the effluent to a water body or slow infiltration in the soil, complying with Colombian norms in force. The process included a state-of-the-art revision, design of this kind of plants (such as Carrión de los Céspedes in Andalucía, Spain; UFMG/COPASA plant in Minas Gerais-Brazil, works conducted in Colombia (IDEAM-CINARA-UTP, and tests performed by Madera, Silva, and Peña from CINARA in a pilot plant. Area estimated for construction of systems proposed reaches 18,000 m² and fixed costs for construction of the plant is estimated in 850 million Colombian pesos for treating a 1.5 l/s flow of household waste water.

  2. Fire and EMS Districts - MDC_FDStationTerritoryInhabited

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — A polygon feature class of Miami-Dade County Fire Rescue (MDFR) Fire District Station Territories clipped to the extent of inhabited areas. This layer is intended...

  3. Phylogeny of rock-inhabiting fungi related to Dothideomycetes

    NARCIS (Netherlands)

    Ruibal, C.; Gueidan, C.; Selbmann, L.; Gorbushina, A.A.; Crous, P.W.; Groenewald, J.Z.; Muggia, L.; Grube, M.; Isola, D.; Schoch, C.L.; Staley, J.T.; Lutzoni, F.; Hoog, de G.S.

    2009-01-01

    The class Dothideomycetes (along with Eurotiomycetes) includes numerous rock-inhabiting fungi (RIF), a group of ascomycetes that tolerates surprisingly well harsh conditions prevailing on rock surfaces. Despite their convergent morphology and physiology, RIF are phylogenetically highly diverse in

  4. Modern estuarine siliceous spiculites, Tasmania, Australia: A non-polar link to Phanerozoic spiculitic cherts

    Science.gov (United States)

    Reid, C. M.; James, N. P.; Kyser, T. K.; Barrett, N.; Hirst, A. J.

    2008-02-01

    Biosiliceous sedimentary rocks are well known from the geologicrecord and many are correctly interpreted to have formed indeep-water or cold-water environments. Shallow non-polar spiculitesare also known from the rock record, yet no modern analog hasbeen documented for such environments. Bathurst Harbour, anestuarine system in southwest Tasmania, provides this much-neededmodern analog. In this system a sharp halocline separates tannin-richlow-salinity surface waters from clear marine bottom waters.Tannins supply few nutrients and substantially reduce lightpenetration to bottom environments, resulting in a thinned photiczone and the mixing of deeper-water sub-photic biotas of softcorals, bryozoans, and sponges with other organisms more typicalof this temperate shallow-water environment. The well-definedhalocline allows a typically marine biota, including echinoderms,to live in bottom waters of this estuarine setting. The bioclasticfactory, producing both carbonate and siliceous particles, existsin marine subphotic bottom waters of incised channel and shallowrocky environments along the shoreline. Extensive organic-richsoft sediments in protected embayments generate few bioclasts,but contain allochthonous sponge spicules transported from theadjacent bioclastic factory. Trapping of organic material withinthe estuarine system lowers sediment pH and promotes dissolutionof carbonate biofragments, resulting in preferential preservationof siliceous sponge spicules. This situation implies that manybiosiliceous neritic deposits in the rock record may be theresult of similar preferential preservation.

  5. Vicissitudes of oxidative stress biomarkers in the estuarine crab Scylla serrata with reference to dry and wet weather conditions in Ennore estuary, Tamil Nadu, India.

    Science.gov (United States)

    Ragunathan, M G

    2017-03-15

    The primary objective of this study was to understand the impact of monsoon and summer seasons on the Polychlorinated Biphenyls (PCB's) and petroleum hydrocarbon compounds (PHC's) load in Ennore estuary and how the physiological response of estuarine Scylla serrata inhabiting in this estuary changed with reference to antioxidant defense. Seasonal levels of PCB's and PHC's were assessed in the water along with their bioaccumulation in gills, hemolymph, hepatopancreas and ovary of S. serrata. Concentration of PCB's and PHC's in water and their bioaccumulation was found to be higher in summer season when compared to monsoon season. Enzymic antioxidant assays [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), glutathione-S-transferase (GST)]; non-enzymic antioxidant assays [glutathione (GSH), vitamin C, vitamin E] and macromolecular alterations [membrane lipid peroxidation (LPO), and DNA Damage (strand breaks)] were assessed in the gills, hemolymph and hepatopancreas of S. serrata. There was a significant (p<0.05) upregulation in lipid peroxidation activity and DNA damage activity collected during the summer season when compared to the pre- and post-monsoon seasons. On the contrary, the enzymic and non-enzymic antioxidants exhibited significant (p<0.05) down regulation in the gills, hemolymph, hepatopancreas and ovary of S. serrata. Oxidative stress biomarkers represented a significant (p<0.05) maximum in gills when compared to hemolymph and hepatopancreas of S. serrata. Present study provided scientific evidences of how the antioxidant defense status of S. serrata responded to PCB's and PAH's stress with reference to seasonal vicissitudes, which indirectly represented the environmental health conditions of the estuary. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Mid-depth temperature maximum in an estuarine lake

    Science.gov (United States)

    Stepanenko, V. M.; Repina, I. A.; Artamonov, A. Yu; Gorin, S. L.; Lykossov, V. N.; Kulyamin, D. V.

    2018-03-01

    The mid-depth temperature maximum (TeM) was measured in an estuarine Bol’shoi Vilyui Lake (Kamchatka peninsula, Russia) in summer 2015. We applied 1D k-ɛ model LAKE to the case, and found it successfully simulating the phenomenon. We argue that the main prerequisite for mid-depth TeM development is a salinity increase below the freshwater mixed layer, sharp enough in order to increase the temperature with depth not to cause convective mixing and double diffusion there. Given that this condition is satisfied, the TeM magnitude is controlled by physical factors which we identified as: radiation absorption below the mixed layer, mixed-layer temperature dynamics, vertical heat conduction and water-sediments heat exchange. In addition to these, we formulate the mechanism of temperature maximum ‘pumping’, resulting from the phase shift between diurnal cycles of mixed-layer depth and temperature maximum magnitude. Based on the LAKE model results we quantify the contribution of the above listed mechanisms and find their individual significance highly sensitive to water turbidity. Relying on physical mechanisms identified we define environmental conditions favouring the summertime TeM development in salinity-stratified lakes as: small-mixed layer depth (roughly, ~< 2 m), transparent water, daytime maximum of wind and cloudless weather. We exemplify the effect of mixed-layer depth on TeM by a set of selected lakes.

  7. Influence of Oceanic and Estuarine Drivers on Wetland Shoreline Change: Moving Towards a Framework for Assessment of Coastal Erosion Hazards Along Sheltered Coasts

    Science.gov (United States)

    Plant, N. G.; Smith, K. E. L.; Doran, K. S.; Smith, C. G.; Stockdon, H. F.

    2015-12-01

    Barrier island and estuarine habitats act as natural buffers to wave energy and reduce erosion of mainland coasts; however, estuarine wetlands are under increasing threat from shoreline destabilization and erosion due to rising sea level and storms. Currently, the USGS National Assessment of Coastal Change Hazards estimates the vulnerability of shorelines to hurricane erosion hazards by combining physical parameters of dune, beach, and shoreline morphology with storm hydrodynamic predictions. These hazard assessments are limited to ocean-side sandy beaches. However, with the increasing availability of water-penetrating lidar and vegetation filtering algorithms, as well as estuarine wave and hydrodynamic modeling, extending physical process analyses and risk assessments to estuarine and back-barrier shorelines is possible. In this study, we investigate the relationship between shoreline type, sediment supply rate, long-term erosion rates, and shoreline geophysical features. We focus on long-term changes, such as those associated with barrier island landward migration, which is dominated by the processes of storm overwash and sea-level rise. This migration means that the long-term changes in estuarine and ocean-facing shorelines can be correlated. We focus on understanding these correlations with estuarine drivers of wetland shoreline erosion and accretion, such as waves, sediment supply, and shoreline features. Quantitatively assessing the variance of estuarine shoreline behavior relative to oceanic shorelines will improve knowledge of estuarine shoreline susceptibility to storm-induced erosion, help fine-tune estimates of future forecasts of coastal change, and provide an initial framework for estimating erosion hazards along sheltered coasts.

  8. Impact of estuarine pollution on birds

    Science.gov (United States)

    Blus, L.J.; Wiemeyer, Stanley N.; Kerwin, J.A.; Stendell, R.C.; Ohlendorf, H.M.; Stickel, L.F.

    1977-01-01

    Pollution of estuaries affects bird populations indirectly through changes in habitat and food supply. The multi-factor pollution of Chesapeake Bay has resulted in diminution of submerged aquatic plants and consequent change in food habits of the canvasback duck. Although dredge-spoil operations can improve wildlife habitat, they often result in its demise. Pollution of estuaries also affects birds directly, through chemical toxication, which may result in outright mortality or in reproductive impairment. Lead from industrial sources and roadways enters the estuaries and is accumulated in tissues of birds. Lead pellets deposited in estuaries as a result of hunting are consumed by ducks with sufficient frequency .to result m large annual die-offs from lead poisoning. Fish in certain areas, usually near industrial sources, may contain levels of mercury high enough to be hazardous to birds that consume them. Other heavy metals are present in estuarine birds, but their significance is poorly known. Oil exerts lethal or sublethal effects on birds by oiling their feathers, oiling eggs and young by contaminated parents, and by ingestion of oil-contaminated food. Organochlorine chemicals, of both agricultural and industrial origin, travel through the food chains and reach harmful levels in susceptible species of birds in certain estuarine ecosystems. Both outright mortality and reproductive impairment have occurred.

  9. Estimating flood exceedance probabilities in estuarine regions

    Science.gov (United States)

    Westra, Seth; Leonard, Michael

    2016-04-01

    Flood events in estuarine regions can arise from the interaction of extreme rainfall and storm surge. Determining flood level exceedance probabilities in these regions is complicated by the dependence of these processes for extreme events. A comprehensive study of tide and rainfall gauges along the Australian coastline was conducted to determine the dependence of these extremes using a bivariate logistic threshold-excess model. The dependence strength is shown to vary as a function of distance over many hundreds of kilometres indicating that the dependence arises due to synoptic scale meteorological forcings. It is also shown to vary as a function of storm burst duration, time lag between the extreme rainfall and the storm surge event. The dependence estimates are then used with a bivariate design variable method to determine flood risk in estuarine regions for a number of case studies. Aspects of the method demonstrated in the case studies include, the resolution and range of the hydraulic response table, fitting of probability distributions, computational efficiency, uncertainty, potential variation in marginal distributions due to climate change, and application to two dimensional output from hydraulic models. Case studies are located on the Swan River (Western Australia), Nambucca River and Hawkesbury Nepean River (New South Wales).

  10. Triclosan alterations of estuarine phytoplankton community structure.

    Science.gov (United States)

    Pinckney, James L; Thompson, Laura; Hylton, Sarah

    2017-06-15

    Antimicrobial additives in pharmaceutical and personal care products are a major environmental concern due to their potential ecological impacts on aquatic ecosystems. Triclosan (TCS) has been used as an antiseptic, disinfectant, and preservative in various media. The sublethal and lethal effects of TCS on estuarine phytoplankton community composition were investigated using bioassays of natural phytoplankton communities to measure phytoplankton responses to different concentrations of TCS ranging from 1 to 200μgl -1 . The EC 50 (the concentration of an inhibitor where the growth is reduced by half) for phytoplankton groups (diatoms, chlorophytes, cryptophytes) examined in this ranged from 10.7 to 113.8μg TCS l -1 . Exposures resulted in major shifts in phytoplankton community composition at concentrations as low as 1.0μg TCS l -1 . This study demonstrates estuarine ecosystem sensitivity to TCS exposure and highlights potential alterations in phytoplankton community composition at what are typically environmental concentrations of TCS in urbanized estuaries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Distribution of the Luminous Bacterium Beneckea harveyi in a Semitropical Estuarine Environment.

    Science.gov (United States)

    O'brien, C H; Sizemore, R K

    1979-11-01

    Bioluminescent bacteria were found in the water column, sediment, shrimp, and gastrointestinal tract of marine fishes from the semitropical estuarine environment of the East Lagoon, Galveston Island, Tex. Populations in the water column decreased during cold weather while sedimentary populations persisted. The highest percentages of luminous organisms were isolated from the gastrointestinal tract of marine fishes, where they persisted during 5 days of starvation. The presence of chitin temporarily increased intestinal populations. All isolates were Beneckea harveyi, whose natural habitat appears to be the gut of fishes and whose free-living reservoir appears to be marine sediments.

  12. Dissolved Vanillin as Tracer for Estuarine Lignin Conversion

    Science.gov (United States)

    Edelkraut, F.

    1996-12-01

    Lignin is produced only by vascular plants and therefore can be used as a tracer for terrestrial organic carbon input to the estuarine and marine environments. Lignin measurements have been done by analyses of the oxidation products such as vanillin or 4-hydroxybenzaldehyde. In the Elbe Estuary, free dissolved vanillin was analysed in order to test whether such measurements yield information on terrestrial carbon inputs into the Estuary and on the vanillin derived from lignin oxidation. In the period 1990-1992, concentrations of dissolved vanillin in the Elbe ranged from 0 to 60 μ g l -1(mean: 8 μg l -1). Higher values were found in areas of increased microbial activity such as the turbidity zone and the river mouth where the water chemistry is influenced by large tidal flats. No correlation was found between dissolved vanillin and suspended matter concentrations, although lignin is normally associated with suspended particulate matter, nor was a covariance seen between dissolved vanillin and the terrestrial carbon inputs into the Estuary. Apparently, biological conversion of lignin was faster than the transport processes, and local sources were more dominant for the vanillin concentration than riverine sources. The dissolved vanillin turnover was fast and, consequently, a significant amount of lignin may be converted within an estuary. In sediments from the Estuary, the concentrations of dissolved vanillin were similar to those found in the water phase and showed no clear vertical profile. The sediment is unlikely to be the source for vanillin.

  13. Comparing Measures of Estuarine Ecosystem Production in a ...

    Science.gov (United States)

    Anthropogenic nutrient enrichments and concerted efforts at nutrient reductions, compounded with the influences of climate change, are likely changing the net ecosystem production (NEP) of our coastal systems. To quantify these changes, scientists monitor a range of physical, chemical, and biological parameters sampled at various frequencies. Water column chlorophyll concentrations are arguably the most commonly used indicator of net phytoplankton production, as well as a coarse indicator of NEP. We compared parameters that estimate production, including chlorophyll, across an experimental nutrient gradient and in situ in both well-mixed and stratified estuarine environments. Data from an experiment conducted in the early 1980s in mesocosms designed to replicate a well-mixed mid-Narragansett Bay (Rhode Island) water column were used to correlate changes in chlorophyll concentrations, pH, dissolved oxygen (O2), dissolved inorganic nitrogen, phosphate, and silicate concentrations, cell counts, and 14C carbon uptake measurements across a range of nutrient enrichments. The pH, O2, nutrient, and cell count measurements reflected seasonal cycles of spring blooms followed by late summer/early fall respiration periods across nutrient enrichments. Chlorophyll concentrations were more variable and rates of 14C productivity were inconsistent with observed trends in nutrient concentrations, pH, and O2 concentrations. Similar comparisons were made using data from a well-mixe

  14. Building a new regulatory paradigm for coastal and estuarine acidification

    Science.gov (United States)

    Brodeur, J.; Cai, W. J.

    2016-12-01

    Ocean acidification regulation generally falls under the authority of the Clean Water Act (CWA, P.L. 92-500). The CWA has been a powerful tool to improve the country's water quality, but it is most adept at addressing point-source pollutants and contaminants. It requires policymakers to determine "natural levels" of the target pollutant and to attribute changes in water quality to a specific source, both of which are tough or impossible tests for the diffuse carbon imbalance that is associated with ocean acidification, even if we could easily identify the threshold level for harm to organisms (Boehm, 2015). Even where regulators have tried to apply CWA to address acidification, they have been confronted by a lack of baseline data, an inability to specifically identify sources within their jurisdiction, and the fact that existing water quality standards do not capture the impairments that are associated with ocean acidification (Cooley, 2015). In fact, there was a lawsuit brought by the Center for Biological Diversity against the U.S. Environmental Protection Agency (EPA) alleging the agency had failure to regulate this issue. In the end, the courts sided with the EPA, and it continues to struggle with how to use pH and/or saturation state to define a point at which a water body becomes impaired and a threat to sea-life and natural resources. We present an analysis of the complexities related to regulating ocean acidification, the history of work in this area, and suggest a solution that can be tailored to fit unique coastal and estuarine characteristics.

  15. MODELLING OF SEDIMENTS CONCENTRATION DISTRIBUTION IN DREDGED CANALS OF THE NIGER DELTA ESTUARINE REGION, NIGERIA

    Directory of Open Access Journals (Sweden)

    Charles Chizom Dike

    2013-01-01

    Full Text Available Previous sediments concentration distributi on models used in the study of sediment characteristics of the dredged canals in the Niger-Delta estuarine region, Nigeria; did not take into consideration the lateral in flow due to tidal effects, which affects tremendously, the sediment intake into the estuarine waters. In the current research, existing models are modified by incorpora ting the missing lateral inflow parameters, which are peculiar to the Niger Delta environment, to obtain more accurate model results. Details are given herein, of the deve lopment and application of a 3-dimensional numerical model (EKU 2.8 Models to predict sediment concentration distribution (total suspended sediment & bed sediment load s in the Niger Delta estuarine canals, with Ekulama well 19 access canal as a case study. The approach in this paper involved coupling a sediment transport equation (w ith the inclusion of lateral inflow parameters, with an estuarine hydro-dy namics equation to generate a generic 3- dimensional sediment concentration distribu tion model, using deterministic approach. Predicted results using this model compar ed favorably with measured field results. Average sediment concentration of 29mg/l was obtained compared with 31mg/l measured in the field for bed sediment loads. Finally, the predicted sediment concentration distribution (TSS, when comp ared with field results, gave average correlation coefficient of 0.9.; hence, the present model will assist in generating adequate information /data on sediment ch aracteristics and transport mechanism, required for effective design of canals to redu ce rate of siltation. The application of the above knowledge/parameters generated from this model to effectively design canals to reduce siltation will be treated in subsequent articles.

  16. The inhabitants of Lund and Gaevle and the legacy of Chernobyl a preliminary study

    International Nuclear Information System (INIS)

    Erlandsson, B.

    1999-01-01

    The body burden of 137 Cs in the population of two Swedish cities, Lund and Gaevle has been calculated from measurements of the activity concentration in the sewage sludge from sewage treatment plants serving these cities. Now 13 years after the Chernobyl accident the activity in the run-off water during the winter season, January to March, and during dry periods is very low. Already 1996, 10 years after the accident, the distribution of the mean value of the activity concentration of 137 Cs has leveled out, and does not depend on the amount of precipitation. Therefor almost all 137 Cas activity can be determined as coming from the inhabitants of the two cities. The number of inhabitants and the distribution of men, women and children are well known for both Lund and Gaevle. These values are in good agreement with values obtained from whole-body measurements. (au)

  17. Sediment measurement in estuarine and coastal areas

    Science.gov (United States)

    Shelley, P. E.

    1976-01-01

    A survey of uses of estuarine and coastal areas is given. Problems associated with these uses are discussed, and data needs for intelligent management of these valuable areas are outlined. Suspended sediment measurements are seen to be one of the greatest needs. To help understand the complexity of the problem, a brief discussion of sediment mechanics is given, including sediment sources, characteristics, and transport. The impact of sediment mechanics on its direct measurement (sampling and analysis) is indicated, along with recommendations for directly obtaining representative data. Indirect measurement of suspended sediment by remote sensors is discussed both theoretically and in the light of some recent experiences. The need for an integrated, multidisciplinary program to solve the problem of quantitatively measuring suspended sediment with remote sensors is stressed, and several important considerations of such a program and benefits to be derived therefrom are briefly addressed.

  18. Survey of Tsuruga inhabitants concerning radiation and its risks

    International Nuclear Information System (INIS)

    Shinoda, Yoshihiko; Yamano, Naoki

    2015-01-01

    The Fukushima Daiichi nuclear accident has led to changes in the acceptance of nuclear power in many people. The authors conducted an opinion survey of 300 adult inhabitants of Tsuruga city in Fukui prefecture, Japan. The aim of this survey is to obtain people's opinions concerning radiation and its risks. Authors classified Tsuruga inhabitants on the basis of responses to questions on the concept and knowledge of risk and the cognition of radiation by factor and cluster analyses of multivariable analysis. Using the results of these analyses, Tsuruga inhabitants have been assigned to five categories: “acceptance group,” “anxiety group,” and three intermediate groups. (author)

  19. Evaluation of HCMM satellite data for estuarine tidal circulation patterns and thermal inertia soil moisture measurements. [Delaware Bay, Cooper River, and the Potomac River estuaries; Luverne, Minnesota, soil moisture, and water temperature of Lake Anna, Virginia

    Science.gov (United States)

    Wiesnet, D. R.; Mcginnis, D. F., Jr. (Principal Investigator); Matson, M.; Pritchard, J. A.

    1981-01-01

    Digital thermal maps of the Cooper River (SC) and the Potomac River estuaries were prepared from heat capacity mapping radiometer (HCMR) tapes. Tidal phases were correctly interpreted and verified. Synoptic surface circulation patterns were charted by location thermal fronts and water mass boundaries within the estuaries. Thermal anomalies were detected adjacent of a conventional power plant on the Potomac. Under optimum conditions, estuaries as small as the Cooper River can be monitored for generalized thermal/tidal circulation patterns by the HCMM-type IR sensors. The HCMM thermal inertia approach to estimating soil moisture at the Luverne (MN) test site was found to be unsatisfactory as a NESS operational satellite technique because of cloud cover interference. Thermal-IR data show similar structure of the Baltimore and Washington heat islands when compared to NOAA AVHRR thermal-IR data. Thermal anomalies from the warm water discharge water of a nuclear power plant were mapped in Lake Anna, Virginia.

  20. Environmental influences on the spatial ecology and spawning behaviour of an estuarine-resident fish, Macquaria colonorum

    Science.gov (United States)

    Walsh, C. T.; Reinfelds, I. V.; Ives, M. C.; Gray, C. A.; West, R. J.; van der Meulen, D. E.

    2013-02-01

    Estuarine-resident fishes are highly susceptible to the effects of environmental and anthropogenic impacts on their assemblages and habitats. We investigated the distribution, movement and spawning behaviour of estuary perch, Macquaria colonorum, in response to selected environmental variables using an acoustic telemetry array in a large tidal river in south-eastern (SE) Australia. Adult M. colonorum were monitored for up to two years, covering two consecutive spawning periods between September 2007 and 2009. Salinity, water temperature and river flows all had a significant relationship with their estuarine distribution. In particular, large-scale movements were influenced by large freshwater inflow events and the resultant reduction in salinity levels, together with the seasonal cooling and warming trends in water temperatures associated with spawning behaviour. During the winter months, male and female M. colonorum migrated from their upper estuarine home ranges to the lower estuarine spawning grounds in synchrony, with numbers of individual visits by both sexes consistently higher in the 'wetter' winter/spring period of 2008. Location, arrival, departure and occupation time within the spawning grounds were similar between sexes and years. Both resident and migrating M. colonorum exhibited strong diel, and to a lesser extent, tidal behavioural patterns, with fish more likely to be detected at night and during the ebb tides. It is postulated that the effect of environmental fluctuations on the distribution and movement of M. colonorum is influenced by behavioural mechanisms in response to osmoregulatory stress, predator-prey interactions and reproductive activity. The results also demonstrate the importance of accounting for autocorrelation inherent in telemetry data, and for developing management strategies that are more robust to the effect of future climate trends on estuarine fish populations.

  1. SPECIES INTERACTIONS BETWEEN ESTUARINE DETRITIVORES: INHIBITION OR FACILITATION?

    Science.gov (United States)

    Native Hawaiian estuarine detritivores; the prawn Macrobrachium grandimanus, and the neritid gastropod Neritina vespertina, were maintained in flow-through microcosms with conditioned leaves from two riparian tree species, Hau (Hibiscus tiliaceus) and guava (Psidium guajava). Th...

  2. Connecting fishery sustainability to estuarine habitats and nutrient loading

    Science.gov (United States)

    The production of several important fishery species depends on critical estuarine habitats, including seagrasses and salt marshes. Relatively simple models can be constructed to relate fishery productivity to the extent and distribution of these habitats by linking fishery-depend...

  3. Brackishwater shrimp farming: Possible impacts on estuarine ecosystem

    Digital Repository Service at National Institute of Oceanography (India)

    Achuthankutty, C.T.; Sreepada, R.A.

    , most the developments have been confined to the estuarine and brackishwater areas. Tropical estuaries being the most productive ecosystem and subjected to a variety of developmental activities, most of which bring in some environmental changes...

  4. Benthic foraminiferal biocoenoses in the estuarine regimes of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Setty, M.G.A.P.

    Benthic Foraminifera are highly responsive to subtle changes in the estuarine environment. Keeping this in view, a qualitative analysis of living benthic Foraminifera was made of the samples collected from the Mandovi-Zuari estuaries...

  5. NOAA's Estuarine Living Marine Resources (ELMR) Data Base

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In 1985, NOAA launched the Estuarine Living Marine Resources (ELMR) Program to develop a consistent data base on the distribution, relative abundance, and life...

  6. Fungal activity in Mangalvan: an estuarine mangrove ecosystem

    Digital Repository Service at National Institute of Oceanography (India)

    Prabhakaran, N.; Gupta, R.; Kutty, M.K.

    of the mangrove vegetation by these fungi the detritus load is increased, contributing substantially to the food web of this important estuarine ecosystem. Thirty-one fungal isolates were recorded from the soil and 27 from decaying leaves, stems, roots...

  7. Ecosystem variability along the estuarine salinity gradient: Examples from long-term study of San Francisco Bay

    Science.gov (United States)

    Cloern, James E.; Jassby, Alan D.; Schraga, Tara; Kress, Erica S.; Martin, Charles A.

    2017-01-01

    The salinity gradient of estuaries plays a unique and fundamental role in structuring spatial patterns of physical properties, biota, and biogeochemical processes. We use variability along the salinity gradient of San Francisco Bay to illustrate some lessons about the diversity of spatial structures in estuaries and their variability over time. Spatial patterns of dissolved constituents (e.g., silicate) can be linear or nonlinear, depending on the relative importance of river-ocean mixing and internal sinks (diatom uptake). Particles have different spatial patterns because they accumulate in estuarine turbidity maxima formed by the combination of sinking and estuarine circulation. Some constituents have weak or no mean spatial structure along the salinity gradient, reflecting spatially distributed sources along the estuary (nitrate) or atmospheric exchanges that buffer spatial variability of ecosystem metabolism (dissolved oxygen). The density difference between freshwater and seawater establishes stratification in estuaries stronger than the thermal stratification of lakes and oceans. Stratification is strongest around the center of the salinity gradient and when river discharge is high. Spatial distributions of motile organisms are shaped by species-specific adaptations to different salinity ranges (shrimp) and by behavioral responses to environmental variability (northern anchovy). Estuarine spatial patterns change over time scales of events (intrusions of upwelled ocean water), seasons (river inflow), years (annual weather anomalies), and between eras separated by ecosystem disturbances (a species introduction). Each of these lessons is a piece in the puzzle of how estuarine ecosystems are structured and how they differ from the river and ocean ecosystems they bridge.

  8. Entry into, and resuscitation from, the viable but nonculturable state by Vibrio vulnificus in an estuarine environment.

    Science.gov (United States)

    Oliver, J D; Hite, F; McDougald, D; Andon, N L; Simpson, L M

    1995-07-01

    Using plate counts, total cell counts, and direct viable counts, we examined the fate of cells of Vibrio vulnificus placed into natural estuarine waters during both winter and summer months. Cells inoculated into membrane diffusion chambers and placed into estuarine waters entered into a viable but nonculturable (VBNC) state in January and February, when the water temperatures were low (average, < 15 degrees C). In contrast, when cells in the VBNC state were placed into the same waters in the warmer months of August through November (average water temperature of ca. 21 degrees C), the cells appeared to undergo a rapid (typically, within 24 h) resuscitation to the fully culturable state. These results were independent of whether the cells were in the logarithmic or stationary phase and whether they were encapsulated or not. This study indicates that the inability to isolate V. vulnificus from cold estuarine sites may be accounted for by entrance of the cells into a VBNC state and that recovery from this state in natural environments may result from a temperature upshift.

  9. Diversity and stability of an estuarine trophic network

    OpenAIRE

    Lobry, Jeremy; David, V; Pasquaud, S; Lepage, M; Sautour, B; Rochard, E

    2008-01-01

    Estuarine areas provide highly valuable ecosystem benefits for human populations, despite being under intense demographic, economic and ecological pressures. Hence, an understanding of the structure and function of estuarine ecosystems is essential for understanding the persistence and stability of these ecosystems and their response to perturbations. This study synthesises available data and knowledge about the Gironde estuary (SW France) in a mass-balanced trophic model to illustrate potent...

  10. INTRODUCTION The habit of chewing khat by the inhabitants of ...

    African Journals Online (AJOL)

    hi-tech

    2000-06-01

    Jun 1, 2000 ... The habit of chewing khat by the inhabitants of. Eastern Africa and Arabian peninsula has a long history. Reference to its use and effects are found in old Arabian literature and in the account of Carten Niebuhrat, an eighteenth century traveller(1). Khat refers to the young leaves and shoots of the plant Catha ...

  11. Species and genetic diversity in the genus Drosophila inhabiting the ...

    Indian Academy of Sciences (India)

    addition, it is neither a pest nor a vector. D. melanogaster is the most extensively used species in the genus. ..... inhabiting different localities in north. The south experiences a tropical and humid climate. ... icant changes in the frequency of inversion heterozygotes in natural populations from Nilgiri range in south India. They.

  12. Inhabiting compassion: A pastoral theological paradigm | Zylla | HTS ...

    African Journals Online (AJOL)

    Inspired by the vision of care in Vincent van Gogh's depiction of the parable of the Good Samaritan, this article offers a paradigm for inhabiting compassion. Compassion is understood in this article as a moral emotion that is also a pathocentric virtue. This definition creates a dynamic view of compassion as a desire to ...

  13. Migration of inhabitants in creative occupations in Slovenia

    Directory of Open Access Journals (Sweden)

    Jani Kozina

    2013-12-01

    Full Text Available The article presents the basic temporal and spatial characteristics of the migration of inhabitants in creative occupations in Slovenia. While it has been already stated that an educated and more creative workforce has been moving out of the country recently and that incoming migrants are mostly low-skilled workers from the former Yugoslavian republics, the content of this article refers mainly to internal migration. The completed analytical work can be summarized as indicating that inhabitants in creative occupations in Slovenia are very immobile and by this criterion quite similar to other occupational groups. If we use the same criterion to compare them with inhabitants in creative occupations from abroad, we can conclude that they are most similar to those living in southern and eastern Europe – groups considered to be among the least mobile on the old continent. Further analysis showed that the inhabitants in creative occupations that live in more developed regions generally intensely migrate and are also more willing to relocate. Both characteristics are equally valid for the more urbanized settlements.

  14. Sediment composition influences spatial variation in the abundance of human pathogen indicator bacteria within an estuarine environment.

    Science.gov (United States)

    Perkins, Tracy L; Clements, Katie; Baas, Jaco H; Jago, Colin F; Jones, Davey L; Malham, Shelagh K; McDonald, James E

    2014-01-01

    Faecal contamination of estuarine and coastal waters can pose a risk to human health, particularly in areas used for shellfish production or recreation. Routine microbiological water quality testing highlights areas of faecal indicator bacteria (FIB) contamination within the water column, but fails to consider the abundance of FIB in sediments, which under certain hydrodynamic conditions can become resuspended. Sediments can enhance the survival of FIB in estuarine environments, but the influence of sediment composition on the ecology and abundance of FIB is poorly understood. To determine the relationship between sediment composition (grain size and organic matter) and the abundance of pathogen indicator bacteria (PIB), sediments were collected from four transverse transects of the Conwy estuary, UK. The abundance of culturable Escherichia coli, total coliforms, enterococci, Campylobacter, Salmonella and Vibrio spp. in sediments was determined in relation to sediment grain size, organic matter content, salinity, depth and temperature. Sediments that contained higher proportions of silt and/or clay and associated organic matter content showed significant positive correlations with the abundance of PIB. Furthermore, the abundance of each bacterial group was positively correlated with the presence of all other groups enumerated. Campylobacter spp. were not isolated from estuarine sediments. Comparisons of the number of culturable E. coli, total coliforms and Vibrio spp. in sediments and the water column revealed that their abundance was 281, 433 and 58-fold greater in sediments (colony forming units (CFU)/100g) when compared with the water column (CFU/100ml), respectively. These data provide important insights into sediment compositions that promote the abundance of PIB in estuarine environments, with important implications for the modelling and prediction of public health risk based on sediment resuspension and transport.

  15. A Miocene wave-dominated estuarine system in the Paraíba Basin, northeastern Brazil

    Science.gov (United States)

    Gandini, Rosana; Rossetti, Dilce de Fátima; Netto, Renata Guimarães; Góes, Ana Maria

    2017-11-01

    A number of publications have documented the effect of the Miocene transgression on several coasts of the world. However, this event is incompletely documented along the Brazilian margin, despite the existence of an impressive record of Miocene deposits exposed mostly as several coastal cliffs along more than 5000 km of distance. The transgressive nature of Miocene deposits, so far recognized only in a few localities of northeastern Brazil, needs to be amplified in order to better characterize the impact of the Miocene transgression in eastern South America. In this work, we provide facies analysis of early/middle Miocene strata exposed in the Paraíba Basin, northeastern Brazil, aiming reconstruct the depositional paleoenvironments and analyze their evolution within the context of relative sea-level fluctuations data. The results revealed deposits characterized by several features that were related to the action of tidal currents, such as alternating thicker/thinner forest packages, abundant reactivation surfaces, mud drapes and oppositely-dipping (herringbone) cross sets. These sedimentary structures were associated with an ichnological assemblage indicative of marine-influenced and brackish water, best represented by Ophiomorpha, Planolites-Palaeophycus-Thalassinoides and Thallassinoides-Planolites-Palaeophycus ichnofabrics. Sedimentation occurred in environments consisting of estuarine channel, estuarine central basin, tidal inlet/tidal channel, tidal delta/washover, tidal flat/shoal and foreshore, which were related to an estuarine setting, at least in part of a wave-dominated type. Analysis of facies stratal patterns led to suggest that the estuarine deposits of the Paraíba Basin reflect a rise in relative sea level probably during the transgressive and/or highstand stage of a depositional sequence formed directly overlying Cretaceous rocks. This rise can be correlated with the worldwide early/mid Miocene marine transgression. However, while the eustatic sea

  16. Transient controls on estuarine SPM fluxes: case study in the Dee Estuary, UK.

    Science.gov (United States)

    Amoudry, Laurent; Williams, Megan; Todd, David

    2017-04-01

    Estuaries are a critical interface between land and coastal ocean across which freshwater, suspended particulate matter (SPM), and consequently terrestrial carbon, nutrients and anthropogenic contaminants are exchanged. Suspended particulate matter is closely linked to estuarine turbidity; it affects water quality and estuarine ecology; and it contributes to overall estuarine sediment budgets. However, predicting the response of estuarine ecosystems to climate change and human interventions remains difficult partly due to a lack of comprehensive understanding of SPM concentrations and fluxes across time scales from intratidal to seasonal and interannual variability. We investigate the dynamics of suspended sediment and suspended particulate matter in a hypertidal estuary with a maximum tidal range in excess of 10 m and tidal currents reaching over 1 m/s: the Dee Estuary. This estuary is located in northwest England and outflows in Liverpool Bay, itself in the eastern Irish Sea. The Dee Estuary is a funnel-shaped, coastal plain estuary, which is about 30 km long with a maximum width of 8.5 km at the mouth, and consists of mixed sediments. We focus on field observations, collected during several campaigns in the channels of the Dee Estuary from 2004 to 2009 using acoustic and optical instrumentation, which provide intratidal measurements of flow velocity and suspended sediment, and thus sediment fluxes, over approximately a month. Measurements in February-March 2008 highlight three distinct hydrodynamic regimes: a current dominant regime at neap tides (14-21 February); a combined wave-current regime at spring tides (21-29 February); and a wave dominant regime at neap tide (1-4 March). While analysis of tidal distortion and dominance predicts weak ebb dominant channels, the observations yield flood dominant sediment transport. The net sediment flux exhibits a two-layer structure - import near the bed, export near the surface - that is consistent with the residual

  17. Neurobehavioral effects among inhabitants around mobile phone base stations.

    Science.gov (United States)

    Abdel-Rassoul, G; El-Fateh, O Abou; Salem, M Abou; Michael, A; Farahat, F; El-Batanouny, M; Salem, E

    2007-03-01

    There is a general concern on the possible hazardous health effects of exposure to radiofrequency electromagnetic radiations (RFR) emitted from mobile phone base station antennas on the human nervous system. To identify the possible neurobehavioral deficits among inhabitants living nearby mobile phone base stations. A cross-sectional study was conducted on (85) inhabitants living nearby the first mobile phone station antenna in Menoufiya governorate, Egypt, 37 are living in a building under the station antenna while 48 opposite the station. A control group (80) participants were matched with the exposed for age, sex, occupation and educational level. All participants completed a structured questionnaire containing: personal, educational and medical histories; general and neurological examinations; neurobehavioral test battery (NBTB) [involving tests for visuomotor speed, problem solving, attention and memory]; in addition to Eysenck personality questionnaire (EPQ). The prevalence of neuropsychiatric complaints as headache (23.5%), memory changes (28.2%), dizziness (18.8%), tremors (9.4%), depressive symptoms (21.7%), and sleep disturbance (23.5%) were significantly higher among exposed inhabitants than controls: (10%), (5%), (5%), (0%), (8.8%) and (10%), respectively (Pmobile phone base station antennas in Menoufiya governorate were less than the allowable standard level. Inhabitants living nearby mobile phone base stations are at risk for developing neuropsychiatric problems and some changes in the performance of neurobehavioral functions either by facilitation or inhibition. So, revision of standard guidelines for public exposure to RER from mobile phone base station antennas and using of NBTB for regular assessment and early detection of biological effects among inhabitants around the stations are recommended.

  18. Mercury bioaccumulation in estuarine food webs.

    Science.gov (United States)

    Fry, Brian; Chumchal, Matthew M

    2012-03-01

    We tested for unintended mercury contamination problems associated with estuarine floodplain restoration projects of the Louisiana coastal zone, USA. Barataria Bay and Breton Sound are two neighboring deltaic estuaries that were isolated by levees from the Mississippi River about 100 years ago. These estuaries recently have been reconnected to the nutrient-rich Mississippi River, starting major river diversion (input) flows in 1991 for Breton Sound and in 2004 for Barataria Bay. We collected > 2100 fish over five years from 20 stations in these estuaries to test two hypotheses about Hg bioaccumulation: (H1) Background Hg bioaccumulation in fish would be highest in low-salinity upper reaches of estuaries, and (H2) recent river inputs to these upper estuarine areas would increase Hg bioaccumulation in fish food webs. For H1, we surveyed fish Hg concentrations at several stations along a salinity gradient in Barataria Bay in 2003-2004, a time when this estuary lacked strong river inputs. Results showed that average Hg concentrations in fish communities were lowest (150 ng/g dry mass) in higher salinity areas and -2.4x higher (350 ng/g) in low-salinity oligohaline and freshwater upper reaches of the estuary. For H2, we tested for enhanced Hg bioaccumulation following diversion onset in both estuaries. Fish communities from Breton Sound that had long-term (> 10 years) diversion inputs had -1.7x higher average Hg contents of 610 ng/g Hg vs. 350 ng/g background values. Shorter-term diversion inputs over 2-3 years in upper Barataria Bay did not result in strong Hg enrichments or stable C isotope increases seen in Breton Sound, even though N and S stable-isotope values indicated strong river inputs in both estuaries. It may be that epiphyte communities on abundant submerged aquatic vegetation (SAV) are important hotspots for Hg cycling in these estuaries, and observed lesser development of these epiphyte communities in upper Barataria Bay during the first years of diversion

  19. Trophic Dynamics of Filter Feeding Bivalves in the Yangtze Estuarine Intertidal Marsh: Stable Isotope and Fatty Acid Analyses.

    Directory of Open Access Journals (Sweden)

    Sikai Wang

    Full Text Available Benthic bivalves are important links between primary production and consumers, and are essential intermediates in the flow of energy through estuarine systems. However, information on the diet of filter feeding bivalves in estuarine ecosystems is uncertain, as estuarine waters contain particulate matter from a range of sources and as bivalves are opportunistic feeders. We surveyed bivalves at different distances from the creek mouth at the Yangtze estuarine marsh in winter and summer, and analyzed trophic dynamics using stable isotope (SI and fatty acid (FA techniques. Different bivalve species had different spatial distributions in the estuary. Glauconome chinensis mainly occurred in marshes near the creek mouth, while Sinonovacula constricta preferred the creek. Differences were found in the diets of different species. S. constricta consumed more diatoms and bacteria than G. chinensis, while G. chinensis assimilated more macrophyte material. FA markers showed that plants contributed the most (38.86 ± 4.25% to particular organic matter (POM in summer, while diatoms contributed the most (12.68 ± 1.17% during winter. Diatoms made the largest contribution to the diet of S. constricta in both summer (24.73 ± 0.44% and winter (25.51 ± 0.59%, and plants contributed no more than 4%. This inconsistency indicates seasonal changes in food availability and the active feeding habits of the bivalve. Similar FA profiles for S. constricta indicated that the bivalve had a similar diet composition at different sites, while different δ13C results suggested the diet was derived from different carbon sources (C4 plant Spartina alterniflora and C3 plant Phragmites australis and Scirpus mariqueter at different sites. Species-specific and temporal and/or spatial variability in bivalve feeding may affect their ecological functions in intertidal marshes, which should be considered in the study of food webs and material flows in estuarine ecosystems.

  20. Trophic Dynamics of Filter Feeding Bivalves in the Yangtze Estuarine Intertidal Marsh: Stable Isotope and Fatty Acid Analyses.

    Science.gov (United States)

    Wang, Sikai; Jin, Binsong; Qin, Haiming; Sheng, Qiang; Wu, Jihua

    2015-01-01

    Benthic bivalves are important links between primary production and consumers, and are essential intermediates in the flow of energy through estuarine systems. However, information on the diet of filter feeding bivalves in estuarine ecosystems is uncertain, as estuarine waters contain particulate matter from a range of sources and as bivalves are opportunistic feeders. We surveyed bivalves at different distances from the creek mouth at the Yangtze estuarine marsh in winter and summer, and analyzed trophic dynamics using stable isotope (SI) and fatty acid (FA) techniques. Different bivalve species had different spatial distributions in the estuary. Glauconome chinensis mainly occurred in marshes near the creek mouth, while Sinonovacula constricta preferred the creek. Differences were found in the diets of different species. S. constricta consumed more diatoms and bacteria than G. chinensis, while G. chinensis assimilated more macrophyte material. FA markers showed that plants contributed the most (38.86 ± 4.25%) to particular organic matter (POM) in summer, while diatoms contributed the most (12.68 ± 1.17%) during winter. Diatoms made the largest contribution to the diet of S. constricta in both summer (24.73 ± 0.44%) and winter (25.51 ± 0.59%), and plants contributed no more than 4%. This inconsistency indicates seasonal changes in food availability and the active feeding habits of the bivalve. Similar FA profiles for S. constricta indicated that the bivalve had a similar diet composition at different sites, while different δ13C results suggested the diet was derived from different carbon sources (C4 plant Spartina alterniflora and C3 plant Phragmites australis and Scirpus mariqueter) at different sites. Species-specific and temporal and/or spatial variability in bivalve feeding may affect their ecological functions in intertidal marshes, which should be considered in the study of food webs and material flows in estuarine ecosystems.

  1. Genetic and morphologic differentiation of the Lusitanian toadfish (Halobatrachus didactylus between estuarine and coastal areas in Portugal

    Directory of Open Access Journals (Sweden)

    Joana F. Marques

    2006-12-01

    Full Text Available The Lusitanian toadfish, Halobatrachus didactylus (Bloch and Schneider, 1801, is distributed from the Ghana coast to the Iberian Peninsula, being particularly abundant on the south coast of Portugal. The differentiation of this species along the Portuguese coast was assessed through the analysis of 10 samples, considering morphological characters (20 morphometric and 16 meristic and genetic markers (10 allozymes, 11 loci. Southern samples included estuaries and their adjacent coastal areas, given that this species inhabits both environments, whereas western samples only comprised estuaries. Morphometric and meristic data discriminant analysis evidenced some differentiation between estuarine and coastal populations. This was not entirely corroborated by the genetic analysis, which showed an overall pattern of low FST (0.042 and Nei’s genetic distance, even between geographically distant areas. However, higher values of these parameters were found between estuaries of the south coast and their adjacent coastal areas, suggesting that estuarine systems play a major role in such differentiation. Results are discussed regarding toadfish life-history pattern and Portuguese coast geomorphology, giving an insight into the biological and environmental factors influencing population sub-structuring.

  2. Estuarine Response to River Flow and Sea-Level Rise under Future Climate Change and Human Development

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhaoqing; Wang, Taiping; Voisin, Nathalie; Copping, Andrea E.

    2015-04-01

    Understanding the response of river flow and estuarine hydrodynamics to climate change, land-use/land-cover change (LULC), and sea-level rise is essential to managing water resources and stress on living organisms under these changing conditions. This paper presents a modeling study using a watershed hydrology model and an estuarine hydrodynamic model, in a one-way coupling, to investigate the estuarine hydrodynamic response to sea-level rise and change in river flow due to the effect of future climate and LULC changes in the Snohomish River estuary, Washington, USA. A set of hydrodynamic variables, including salinity intrusion points, average water depth, and salinity of the inundated area, were used to quantify the estuarine response to river flow and sea-level rise. Model results suggest that salinity intrusion points in the Snohomish River estuary and the average salinity of the inundated areas are a nonlinear function of river flow, although the average water depth in the inundated area is approximately linear with river flow. Future climate changes will shift salinity intrusion points further upstream under low flow conditions and further downstream under high flow conditions. In contrast, under the future LULC change scenario, the salinity intrusion point will shift downstream under both low and high flow conditions, compared to present conditions. The model results also suggest that the average water depth in the inundated areas increases linearly with sea-level rise but at a slower rate, and the average salinity in the inundated areas increases linearly with sea-level rise; however, the response of salinity intrusion points in the river to sea-level rise is strongly nonlinear.

  3. Hydrocarbon pollution from marinas in estuarine sediments

    Science.gov (United States)

    Voudrias, Evangelos A.; Smith, Craig L.

    1986-03-01

    A measure of the impact of marinas on three Eastern Virginia estuarine creeks was obtained by a study of hydrocarbons in their sediments. Two of the creeks support considerable marine activity, including pleasure boat marinas, boat repair facilities, and commercial fishing operations. The third creek, which served as a control, is seldom used by boats, and is surrounded by marsh and woodland. Sediments from the creeks with marinas contained significantly higher levels of both aromatic and aliphatic hydrocarbons than did the control. Differences in the concentrations of certain oil-pollution indicators, such as the 17α,21β-hopane homologs and phytane, and low molecular weight aromatic hydrocarbons, are indicative of light petroleum fractions. Most of the aromatic hydrocarbons from all creeks, however, appear to have a pyrogenic origin. Although hydrocarbons from three probable origins (petroleum, pyrogenesis, and recent biosynthesis) were detected in all locations, the petroleum-derived and pyrogenic hydrocarbons were of only minor importance relative to the biogenic hydrocarbons in the control creek.

  4. Investigation of the factors influencing radiocesium concentrations of fish inhabiting natural aquatic ecosystems

    International Nuclear Information System (INIS)

    Jinks, S.M.

    1975-01-01

    Distributions of radioactive and stable cesium were determined in water, sediment, and biota from eight different aquatic ecosystems between 1971 and 1973. The ecosystems included four lakes, fresh and brackish water regions of the Hudson River estuary, and two coastal marine sites. In the Hudson River estuary, the distribution of radiocesium between suspended and dissolved phases in water was found to be a function of salinity. Mean rates of deposition of suspended radiocesium into bottom sediment are calculated from the temporal changes in concentrations of the media, and observed depth distributions in sediment are semi-quantitatively described. Desorption by salt water is identified as the major mechanism for transport of radiocesium from bottom sediment in the lower estuary, and half-times for removal by this mechanism are estimated to be 1.5 to 2.0 years. Suspended-dissolved distributions of radiocesium in water, and depth distributions in sediment are also presented for lake and marine systems. Accumulation of radiocesium by fish is examined in relation to radiocesium distributions in water, sediment, and other biota, and to the chemical characteristics of each ecosystem. Radiocesium dissolved in water was the primary source to the fish in all ecosystems. Sediment inventories of 137 Cs constituted a secondary source which provided as much as 50 percent of the radiocesium in benthic feeding fish in the Hudson River. Dietary intake of 137 Cs is shown to be inversely related to the potassium concentration in the ambient water, and results in an inverse proportionality between the concentration factor in fish and the potassium concentrations in the different freshwater and estuarine ecosystems

  5. Distribution, sources and biogeochemistry of organic matter in a mangrove dominated estuarine system (Indian Sundarbans) during the pre-monsoon

    Science.gov (United States)

    Ray, R.; Rixen, T.; Baum, A.; Malik, A.; Gleixner, G.; Jana, T. K.

    2015-12-01

    The sources and distribution of dissolved organic carbon (DOC), particulate organic carbon (POC) and dissolved inorganic carbon (DIC) in the Indian Sundarbans mangrove and Hooghly estuarine system were examined during the pre-monsoon (summer) 2014. DOC is the dominant form of organic matter (OM) in the studied estuarine waters and represents a mixture of mangrove and riverine sources. Microbial degradation of land derived OM results in a high pCO2 in the Hooghly estuarine waters while enrichment in δ13C-DIC ascribes to CO2 uptake by phytoplankton in the Sundarbans water. Higher δ15N in the particulate organic nitrogen (PON) of the mangrove and marine zone could be associated with enhanced phytoplankton production sustained by nitrate from mangrove derived OM decomposition and/or nitrate imported from the Bay of Bengal. Low organic carbon contents and elemental ratios (TN/TOC) indicate an intense mineralization and transformation of OM in the sediments, resulting insignificantly different OM compositions compared to those of the three major sources: land derived OM, mangrove leaf litter (Avicennia marina) and in situ phytoplankton production.

  6. A user's guide to coping with estuarine management bureaucracy: An Estuarine Planning Support System (EPSS) tool.

    Science.gov (United States)

    Lonsdale, Jemma; Nicholson, Rose; Weston, Keith; Elliott, Michael; Birchenough, Andrew; Sühring, Roxana

    2018-02-01

    Estuaries are amongst the most socio-economically and ecologically important environments however, due to competing and conflicting demands, management is often challenging with a complex legislative framework managed by multiple agencies. To facilitate the understanding of this legislative framework, we have developed a GISbased Estuarine Planning Support System tool. The tool integrates the requirements of the relevant legislation and provides a basis for assessing the current environmental state of an estuary as well as informing and assessing new plans to ensure a healthy estuarine state. The tool ensures that the information is easily accessible for regulators, managers, developers and the public. The tool is intended to be adaptable, but is assessed using the Humber Estuary, United Kingdom as a case study area. The successful application of the tool for complex socio-economic and environmental systems demonstrates that the tool can efficiently guide users through the complex requirements needed to support sustainable development. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  7. 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.

  8. The role of river flow and tidal asymmetry on 1-D estuarine morphodynamics

    NARCIS (Netherlands)

    Guo, L.; Van der Wegen, M.; Roelvink, J.A.; He, Q.

    2014-01-01

    Numerous research efforts have been devoted to understanding estuarine morphodynamics under tidal forcing. However, the impact of river discharge on estuarine morphodynamics is insufficiently examined. Inspired by the Yangtze Estuary, this work explores the morphodynamic impact of river discharge in

  9. Studies on growth and age of bivalves from temperate and tropical estuarine ecosystems

    Digital Repository Service at National Institute of Oceanography (India)

    Parulekar, A.H.

    Comparison of growth progression and age composition of Abra alba and Nuculana minuta from temperate estuarine ecosystem with Meretrix casta and Paphia malabarica from tropical estuarine environment, revealed that the annual growth rate in tropical...

  10. Reversing tidal flow and estuarine morphodynamics in the Metronome laboratory flume

    NARCIS (Netherlands)

    Kleinhans, M.G.; Leuven, J.R.F.W.; Braat, L.; van der Vegt, M.; van Maarseveen, M.C.G.; Markies, H.; Roosendaal, C.; van Eijk, A.M.

    2016-01-01

    Our objective is to test a novel experimental principle for creating reversing tidal flows of sufficient strength to cause estuarine morphodynamics. The study of estuarine morphodynamics has hitherto been limited to field observation and numerical modelling, whilst fluvial morphodynamics have

  11. Metallic copper spray--a new control technique to combat invasive container-inhabiting mosquitoes.

    Science.gov (United States)

    Becker, Norbert; Oo, Thin Thin; Schork, Nino

    2015-11-09

    The control of container-inhabiting mosquitoes is mainly based on environmental management with special emphasis on community participation e.g. source reduction by elimination or modification of water bodies. However, citizens are often not aware of the problems related to urban mosquito control or just ignore the advice provided during anti-mosquito control campaigns. In particular, cemeteries contain favourite breeding sites for container-inhabiting mosquitoes like Ochlerotatus j. japonicus, Culex pipiens s.l./Cx. torrentium, Aedes aegypti or Aedes albopictus. In our study, we investigated whether metallic copper e.g. in form of copper spray can be a suitable and cost-effective tool to combat mosquito breeding in vases or other similar small containers where no commonly used insecticides can be applied. The effect of metallic copper spray in comparison to 5 Euro cent coins or copper tubes at different dosages and water qualities applied in small water collections such as widely used plastic grave vases were evaluated by assessing the mortality rates of larvae of Oc.j. japonicus, Cx. pipiens s.l./Cx. torrentium and Ae.aegypti. Different water qualities were tested to assess the influence of pH on the solubility of the copper ions. The copper concentrations were quantified using ICP/MS (Inductively coupled plasma/Mass spectrometry) in relation to the exposure time and mortality rates of mosquito larvae. All statistical analyses were computed using JMP 10.0.2 (SAS Institute Inc., 2012, Cary, NC, USA). Dosages of less than 500 ppb of copper in the water of small containers led to a 100% mortality rate after 2 weeks for all tested mosquito species by using one or more 5 Euro cent coins/vase. When the interior surface of plastic grave vases was covered by metallic copper spray, all of the tested larvae died after 7-10 days in the laboratory and under field conditions the reduction rate was 99.44% for Oc.j. japonicus and 99.6% for Culex pipiens s.l./Cx. torrentium

  12. Urinary excretion of uranium in adult inhabitants of the Czech Republic

    International Nuclear Information System (INIS)

    Malátová, Irena; Bečková, Věra; Kotík, Lukáš

    2016-01-01

    The main aim of this study was to determine and evaluate urinary excretion of uranium in the general public of the Czech Republic. This value should serve as a baseline for distinguishing possible increase in uranium content in population living near legacy sites of mining and processing uranium ores and also to help to distinguish the proportion of the uranium content in urine among uranium miners resulting from inhaled dust. The geometric mean of the uranium concentration in urine of 74 inhabitants of the Czech Republic was 0.091 mBq/L (7.4 ng/L) with the 95% confidence interval 0.071–0.12 mBq/L (5.7–9.6 ng/L) respectively. The geometric mean of the daily excretion was 0.15 mBq/d (12.4 ng/d) with the 95% confidence interval 0.12–0.20 mBq/d (9.5–16.1 ng/d) respectively. Despite the legacy of uranium mines and plants processing uranium ore in the Czech Republic, the levels of uranium in urine and therefore, also human body content of uranium, is similar to other countries, esp. Germany, Slovenia and USA. Significant difference in the daily urinary excretion of uranium was found between individuals using public supply and private water wells as a source of drinking water. Age dependence of daily urinary excretion of uranium was not found. Mean values and their range are comparable to other countries, esp. Germany, Slovenia and USA. - Highlights: • Urinary uranium content of the inhabitants was experimentally determined. • Significant difference was found between inhabitants and uranium miners. • Higher uranium urinary content was found at users of private wells. • Dependence of urinary content on the age was not found. • The mean value and range of uranium daily excretion is similar to other countries.

  13. Enhanced radioactivity in an estuarine system at the southwest of Spain

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Aguirre, A. [Sevilla Univ. (Spain). Dept. Fisica Aplicada, E.U. Ingenieria Tecnica Agricola

    1997-12-31

    A study of the distribution of natural radionuclides released by a phosphate rock processing factory located in the estuarine system composed by the confluence of the Odiel and Tinto rivers in the Atlantic Ocean has been carried out. This study includes the Odiel river basin, which receives the wastes from this factory, and the Odiel marsh which is highly affected by the influx of Odiel river waters. The study has concluded that the wastes from this industry are the cause of the enhanced radioactivity in the estuarine environment. Moreover, the study of six sequentially leached fractions of bottom sediments has shown that the total U is located in the non-residual fractions of the sediments, coprecipitation with amorphous ferro-manganese oxy-hydroxides being the main process of U incorporation from the water column to bottom sediments. The study of the radioactive concentration in Spartina Densiflora plants from the Odiel marsh has also shown that the discharges from the industries reach the vegetation of the area. (author) 11 refs.

  14. Ubiquity and quantitative significance of bacterioplankton lineages inhabiting the oxygenated hypolimnion of deep freshwater lakes.

    Science.gov (United States)

    Okazaki, Yusuke; Fujinaga, Shohei; Tanaka, Atsushi; Kohzu, Ayato; Oyagi, Hideo; Nakano, Shin-Ichi

    2017-10-01

    The oxygenated hypolimnion accounts for a volumetrically significant part of the global freshwater systems. Previous studies have proposed the presence of hypolimnion-specific bacterioplankton lineages that are distinct from those inhabiting the epilimnion. To date, however, no consensus exists regarding their ubiquity and abundance, which is necessary to evaluate their ecological importance. The present study investigated the bacterioplankton community in the oxygenated hypolimnia of 10 deep freshwater lakes. Despite the broad geochemical characteristics of the lakes, 16S rRNA gene sequencing demonstrated that the communities in the oxygenated hypolimnia were distinct from those in the epilimnia and identified several predominant lineages inhabiting multiple lakes. Catalyzed reporter deposition fluorescence in situ hybridization revealed that abundant hypolimnion-specific lineages, CL500-11 (Chloroflexi), CL500-3, CL500-37, CL500-15 (Planctomycetes) and Marine Group I (Thaumarchaeota), together accounted for 1.5-32.9% of all bacterioplankton in the hypolimnion of the lakes. Furthermore, an analysis of single-nucleotide variation in the partial 16S rRNA gene sequence (oligotyping) suggested the presence of different sub-populations between lakes and water layers among the lineages occurring in the entire water layer (for example, acI-B1 and acI-A7). Collectively, these results provide the first comprehensive overview of the bacterioplankton community in the oxygenated hypolimnion of deep freshwater lakes.

  15. The complex early life history of a marine estuarine-opportunist fish species, Solea turbynei (Soleidae from temperate South Africa

    Directory of Open Access Journals (Sweden)

    Nadine A. Strydom

    2015-06-01

    Full Text Available The early life history stages and ecology of Solea turbynei, a marine estuarine-opportunist species, is described from nursery areas in Algoa Bay, South Africa. Early life history stages were collected over multiple years from known nursery habitats using plankton, fyke and larval seine nets. The larvae are described using morphometric measurements, meristic counts and pigmentation based on 29 individuals. Solea turbynei is differentiated from other Soleidae by the small size at flexion (3-4 mm, low myomere count and presence of two characteristic blotches of pigment on the dorsal fin. This species has a unique early life history strategy in that the larvae progressively span nearshore, surf zone and estuarine habitats with ontogeny. Abundance of preflexion stages peaks in summer in nearshore waters, indicative of peak spawning period but preflexion larvae are present throughout the year, indicating protracted spawning by adults. At flexion stage, larvae utilize surf zones where metamorphosis and settlement takes place. Early juveniles migrate into the sandy lower reaches of estuaries, after which fish take up residency to adulthood. Warm water is important for larval growth and survival in the nearshore, while turbidity shows a positive relationship with recruitment into estuarine nurseries.

  16. Estuarine abandoned channel sedimentation rates record peak fluvial discharge magnitudes

    Science.gov (United States)

    Gray, A. B.; Pasternack, G. B.; Watson, E. B.

    2018-04-01

    Fluvial sediment deposits can provide useful records of integrated watershed expressions including flood event magnitudes. However, floodplain and estuarine sediment deposits evolve through the interaction of watershed/marine sediment supply and transport characteristics with the local depositional environment. Thus extraction of watershed scale signals depends upon accounting for local scale effects on sediment deposition rates and character. This study presents an examination of the balance of fluvial sediment dynamics and local scale hydro-geomorphic controls on alluviation of an abandoned channel in the Salinas River Lagoon, CA. A set of three sediment cores contained discrete flood deposits that corresponded to the largest flood events over the period of accretion from 1969 to 2007. Sedimentation rates scaled with peak flood discharge and event scale sediment flux, but were not influenced by longer scale hydro-meteorological activities such as annual precipitation and water yield. Furthermore, the particle size distributions of flood deposits showed no relationship to event magnitudes. Both the responsiveness of sedimentation and unresponsiveness of particle size distributions to hydro-sedimentological event magnitudes appear to be controlled by aspects of local geomorphology that influence the connectivity of the abandoned channel to the Salinas River mainstem. Well-developed upstream plug bar formation precluded the entrainment of coarser bedload into the abandoned channel, while Salinas River mouth conditions (open/closed) in conjunction with tidal and storm surge conditions may play a role in influencing the delivery of coarser suspended load fractions. Channel adjacent sediment deposition can be valuable records of hydro-meteorological and sedimentological regimes, but local depositional settings may dominate the character of short term (interdecadal) signatures.

  17. Detrital shadows: estuarine food web connectivity depends on fluvial influence and consumer feeding mode.

    Science.gov (United States)

    Howe, Emily; Simenstad, Charles A; Ogston, Andrea

    2017-10-01

    We measured the influence of landscape setting on estuarine food web connectivity in five macrotidal Pacific Northwest estuaries across a gradient of freshwater influence. We used stable isotopes (δ 13 C, δ 15 N, δ 34 S) in combination with a Bayesian mixing model to trace primary producer contributions to suspension- and deposit-feeding bivalve consumers (Mytilus trossulus and Macoma nasuta) transplanted into three estuarine vegetation zones: emergent marsh, mudflat, and eelgrass. Eelgrass includes both Japanese eelgrass (Zostera japonica) and native eelgrass (Zostera marina). Fluvial discharge and consumer feeding mode strongly influenced the strength and spatial scale of observed food web linkages, while season played a secondary role. Mussels displayed strong cross-ecosystem connectivity in all estuaries, with decreasing marine influence in the more fluvial estuaries. Mussel diets indicated homogenization of detrital sources within the water column of each estuary. In contrast, the diets of benthic deposit-feeding clams indicated stronger compartmentalization in food web connectivity, especially in the largest river delta where clam diets were trophically disconnected from marsh sources of detritus. This suggests detritus deposition is patchy across space, and less homogenous than the suspended detritus pool. In addition to fluvial setting, other estuary-specific environmental drivers, such as marsh area or particle transport speed, influenced the degree of food web linkages across space and time, often accounting for unexpected patterns in food web connectivity. Transformations of the estuarine landscape that alter river hydrology or availability of detritus sources can thus potentially disrupt natural food web connectivity at the landscape scale, especially for sedentary organisms, which cannot track their food sources through space. © 2017 by the Ecological Society of America.

  18. Paleoclimatic and paleoceanographic studies of estuarine and marine sediments using strontium isotopes

    International Nuclear Information System (INIS)

    Ingram, B.L.

    1992-01-01

    Strontium isotopic ratio ( 87 Sr/ 86 Sr) measurements in fossil carbonates and phosphates are used to evaluate paleoceanographic and paleoclimatic environments in Quaternary, Pliocene-Pleistocene, and mid-Cretaceous estuarine and marine sediments. The use of 87 Sr/ 86 Sr measurements as an estuarine paleosalinity and paleoclimatic indicator is developed and applied to San Francisco Bay. 87 Sr/ 86 Sr measurements of foraminifer and molluscan fossils contained in estuarine sediments of late Pleistocene (ca 115 to 125 ka) and late Holocene (4.5 ka) age show cyclic variations indicating that salinity fluctuated with periods of several hundred years, probably reflecting wet-dry cycles associated with fluctuations in solar irradiance caused by sunspot cycles. The average salinity in San Pablo and Richardson bays was significantly lower (by 6 to 8%) over much of the past 4.5 ka than at present, reflecting a combination of decreased freshwater inflow at present associated with water diversion and wetter climatic conditions prior to 2000 years ago. Salinity data are converted to river discharge using salinity-delta flow relations derived from historical records for San Francisco Bay. The data indicate that annual freshwater inflow was at least twice the modern pre-diversion average between 2.5 and 3.0 Ka; this time period is also identified as one of wetter climatic conditions by lake level and treeline records from the Sierra Nevada. Strontium isotopic measurements of marine carbonate and fish teeth to middle Cretaceous age are used to increase the resolution of the existing seawater Sr isotope versus time curve and to assess models for global oceanic anoxic events. The new data using fish teeth show less scatter and variability than previous data. Negative excursions in the 87 Sr/ 86 Sr ratio of 7-14 parts in 10 -5 during Aptian anoxic events suggest a link between increased submarine volcanism and oceanic anoxia

  19. Water quality assessment of Gautami–Godavari mangrove estuarine ...

    Indian Academy of Sciences (India)

    food webs (Alongi and Christoffersen 1992). It is a fact that the mangrove forests represent an impor- tant carbon and nutrient source to the adjacent ..... In: The sea (ed.) Hill M N, (New York: Willey) 2 26–77. Robertson A I, Alongi D M and Boto K G 1992 Food chains and carbon fluxes In: Tropical mangrove ecosystems (eds).

  20. Reference values of olfactory function for Mexico City inhabitants.

    Science.gov (United States)

    Guarneros, Marco; Hudson, Robyn; López-Palacios, Martha; Drucker-Colín, René

    2015-01-01

    Olfactory testing is useful in the differential diagnosis of age-related pathologies. To provide baseline reference values for clinical use in Mexico City we investigated the relation between olfactory capabilities and the principal population parameters of age, sex, and smoking habits in a large sample of healthy inhabitants. We applied the internationally recognized and commercially available Sniffin' Sticks test battery to 916 men and women from across the adult life span. The Sniffin' Sticks test evaluates three key aspects of olfactory function: 1) ability to detect an odor, 2) to discriminate between odors, and 3) to identify odors. We found a significant decline in olfactory function from the 5th decade of age, and that detection threshold was the most sensitive measure of this. We did not find a significant difference between men and women or between smokers and non-smokers. In confirmation of our previous studies of the negative effect of air pollution on olfactory function, Mexico City inhabitants had poorer overall performance than corresponding subjects previously tested in the neighboring but less polluted Mexican state of Tlaxcala. Although we basically confirm findings on general demographic patterns of olfactory performance from other countries, we also demonstrate the need to take into account local cultural, environmental and demographic factors in the clinical evaluation of olfactory performance of Mexico City inhabitants. The Sniffin' Sticks test battery, with some adjustment of stimuli to correspond to Mexican culture, provides an easily administered means of assessing olfactory health. Copyright © 2015 IMSS. Published by Elsevier Inc. All rights reserved.

  1. Evaluation of reactivity to Echinococcus spp. among rural inhabitants in Poland.

    Science.gov (United States)

    Cisak, Ewa; Sroka, Jacek; Wójcik-Fatla, Angelina; Zając, Violetta; Dutkiewicz, Jacek

    2015-09-01

    A group of 172 rural inhabitants from eastern Poland (68 males and 104 females, mean age 49.0 ± 12.0 years) was examined for the presence of antibodies against Echinococcus granulosus and Echinococcus multilocularis. A population of 38 healthy urban dwellers from the city of Lublin (17 males and 21 females, mean age 36.2 ± 9.6 years) were examined as a control group. Sera of 22 rural inhabitants (12.8%) reacted positively to Echinococcus granulosus hydatid fluid antigen in the screening test. A cross-reactivity was observed with two serum samples that tested positive in ELISA for E. granulosus. Three serum samples were tested positive for E. multilocularis using the Em2plus ELISA assay and also positive for Western blot. None of the members of control group showed the presence of a seropositive reaction to Echinococcus spp. The reactivity to Echinococcus spp. among rural inhabitants decreased with age and this correlation was statistically significant (R = -0.197151, p = 0.009535). The percentage of positive findings was the highest (50.0%) in the youngest age group (14-20). No significant correlations were found between responses to interview questions (possession of domestic and farm animals, contact with wild animals, eating unwashed berries, drinking unboiled water) and the presence of seropositive reactions to Echinococcus spp. The presented results seem to indicate that echinococcosis is still a current problem in Poland that should not be neglected and, moreover, indicates the need for improvement in the routine laboratory diagnostics of Echinococcus spp. by standardizing the ELISA and Western blot tests.

  2. Extremely Halotolerant and Halophilic Fungi Inhabit Brine in Solar Salterns Around the Globe

    Directory of Open Access Journals (Sweden)

    Polona Zalar

    2014-01-01

    Full Text Available For a long time halotolerant and halophilic fungi have been known exclusively as contaminants of food preserved with high concentrations of either salt or sugar. They were first reported in 2000 to be active inhabitants of hypersaline environments, when they were found in man-made solar salterns in Slovenia. Since then, they have been described in different salterns and salt lakes on three continents. The mycobiota that inhabit these natural hypersaline environments are composed of phylogenetically unrelated halotolerant, extremely halotolerant, and halophilic fungi, which are represented not only by species previously known only as food contaminants, but also by new and rare species. The dominant representatives are different species of black yeast-like and related melanized fungi of the genus Cladosporium, different species within the anamorphic Aspergillus and Penicillium, and the teleomorphic Emericella and Eurotium, certain species of non-melanized yeasts, and Wallemia spp. Until the discovery and description of indigenous saltern mycobiota, the physiological and molecular mechanisms related to salt tolerance in eukaryotic microorganisms were studied using salt-sensitive model organisms. The most studied eukaryotic microorganism was Saccharomyces cerevisiae, which cannot adapt to hypersaline conditions. Species like Debaryomyces hansenii, Aureobasidum pullulans, Hortaea werneckii and Wallemia ichthyophaga, which have now been isolated globally from natural hypersaline environments, represent more suitable model organisms for the study of halotolerance in eukaryotes. Such studies in these species, and particularly with the extremely halotolerant H. werneckii and obligately halophilic W. ichthyophaga have continued to unravel the different strategies that these microorganisms can use to cope with the problems of ion toxicity and low water activity. The focus of this review is to present the main species of fungi inhabiting solar salterns

  3. Nutritional habits of the inhabitants of the island of Vis.

    Science.gov (United States)

    Missoni, Sasa

    2009-12-01

    The island of Vis belongs to middle Dalmatian group of islands with caracteristics Mediterranean climate. The assumption was that the dominant diet of the inhabitants is also Mediterranean. Such diet is considered to be one of the best for the prevention of many complex and chronic diseases, as confirmed by numerous studies in different parts of the World. This study showed a shift in dietary habits in the direction of a more globalized diet. Such sudden shift may prove to be an important trigger for the development of complex diseases such as diabetes melitus type 2, cardiovascular diseases, gout, as well as certain types of cancer.

  4. Pulmonary adiaspiromycosis in the Eurasian beaver (Castor fiber) inhabiting Poland.

    Science.gov (United States)

    Dolka, I; Giżejewska, A; Giżejewski, Z; Kołodziejska-Lesisz, J; Kluciński, W

    2017-09-26

    Adiaspiromycosis is a rare fungal infection caused by saprophytic fungi Emmonsia spp. (type Ascomycota) occurring especially in small free-living mammals. The aim of this study was to evaluate the occurrence of histopathological lesions asscociated with adiaspiromycosis in the Eurasian beaver inhabiting Poland. In order to evaluate the presence of natural adiaspiromycosis we systematically investigated beaver populations from north-eastern Poland for adiaspores in the lungs. This study reveals for the first time the presence of pulmonary adiaspiromycosis of Eurasian beaver in Poland. As far as we know, there is no published data regarding pulmonary adiaspiromycosis in human patients in Poland.

  5. Fatty acids in an estuarine mangrove ecosystem

    Directory of Open Access Journals (Sweden)

    Nabeel M Alikunhi

    2010-06-01

    Full Text Available Los ácidos grasos se han utilizado con éxito para estudiar la transferencia de materia orgánica en las redes alimentarias costeras y estuarinas. Para delinear las interacciones tróficas en las redes, se analizaron perfiles de ácidos grasos en las especies de microbios (Azotobacter vinelandii y Lactobacillus xylosus, camarones (Metapenaeus monoceros y Macrobrachium rosenbergii y peces (Mugil cephalus, que están asociadas con la descomposición de las hojas de dos especies de mangle, Rhizophora apiculata y Avicennia marina. Los ácidos grasos, con excepción de los de cadena larga, exhiben cambios durante la descomposición de las hojas de mangle, con una reducción de los ácidos grasos saturados y un aumento de los monoinsaturados. Los ácidos grasos ramificados están ausentes en las hojas de mangle sin descomponer, pero presentes de manera significativa en las hojas descompuestas, en camarones y peces, representando una fuente importante para ellos. Esto revela que los microbios son productores dominantes que contribuyen significativamente con los peces y camarones en el ecosistema de manglar. Este trabajo demuestra que los marcadores biológicos de los ácidos grasos son una herramienta eficaz para la identificación de las interacciones tróficas entre los productores dominantes y consumidores en este manglar.Fatty acids have been successfully used to trace the transfer of organic matter in coastal and estuarine food webs. To delineate these web connections, fatty acid profiles were analyzed in species of microbes (Azotobacter vinelandii, and Lactobacillus xylosus, prawns (Metapenaeus monoceros and Macrobrachium rosenbergii and finfish (Mugil cephalus, that are associated with decomposing leaves of two mangrove species, Rhizophora apiculata and Avicennia marina. The fatty acids, except long chain fatty acids, exhibit changes during decomposition of mangrove leaves with a reduction of saturated fatty acids and an increase of

  6. The biology and taxonomic status of an estuarine population of ...

    African Journals Online (AJOL)

    The biology and taxonomic status of an estuarine population of Pranesus pinguis (Lacépède) (Teleostei: Atherinidae) in south east Africa. ... The structure and dimensions of the gill rakers related to the diet indicate that, although P. pinguis feeds mainly by capturing individual prey, it is also a facultative filter feeder.

  7. Monitoring nekton as a bioindicator in shallow estuarine habitats

    Science.gov (United States)

    Raposa, K.B.; Roman, C.T.; Heltshe, J.F.

    2003-01-01

    Long-term monitoring of estuarine nekton has many practical and ecological benefits but efforts are hampered by a lack of standardized sampling procedures. This study provides a rationale for monitoring nekton in shallow (< 1 m), temperate, estuarine habitats and addresses some important issues that arise when developing monitoring protocols. Sampling in seagrass and salt marsh habitats is emphasized due to the susceptibility of each habitat to anthropogenic stress and to the abundant and rich nekton assemblages that each habitat supports. Extensive sampling with quantitative enclosure traps that estimate nekton density is suggested. These gears have a high capture efficiency in most habitats and are small enough (e.g., 1 m(2)) to permit sampling in specific microhabitats. Other aspects of nekton monitoring are discussed, including spatial and temporal sampling considerations, station selection, sample size estimation, and data collection and analysis. Developing and initiating long-term nekton monitoring programs will help evaluate natural and human-induced changes in estuarine nekton over time and advance our understanding of the interactions between nekton and the dynamic estuarine environment.

  8. The vertical migration behaviour of estuarine plankton | Grindley ...

    African Journals Online (AJOL)

    A series of investigations on the vertical migration behaviour of estuarine zooplankton have been carried out in recent years. Several of these investigations have been carried out in collaboration with other zoologists and the detailed findings are being published separately. The work is reviewed here and an attempt is ...

  9. The population dynamics of the estuarine isopod Exosphaeroma ...

    African Journals Online (AJOL)

    The population dynamics of the estuarine isopod, Exosphaeroma hylocoetes, was investigated monthly from February 2006 to August 2007 in three temporarily open/closed Eastern Cape estuaries, the East and West Kleinemonde and Kasouga Estuaries. Mean isopod abundances and biomasses ranged between 0 and ...

  10. Oxygen consumption of the estuarine round herring Gilchristella ...

    African Journals Online (AJOL)

    important, in estuarine ecological studies, to assess the response of the metabolic rate to changes in environmental factors. In this study, which forms part of a detailed research programme into .... homeostasis within the salinity range investigated here. Effect of temperature. Temperature effects on the metabolic rate of G.

  11. Assessment of Godavari estuarine mangrove ecosystem through trace metal studies

    Digital Repository Service at National Institute of Oceanography (India)

    Ray, A.K.; Tripathy, S.C; Patra, S.; Sarma, V.V.

    that organic matter is acting as a metal carrier. The values of Pollution Load Index (PLI) were found to be very low, and varied between 0.34-0.60 in KKD bay, 0.47-0.97 in GGE and 0.62-1.03 in CGME indicating that this estuarine ecosystem is not a pollution...

  12. Estuarine use by spotted grunter Pomadasys commersonnii in a ...

    African Journals Online (AJOL)

    Factors influencing estuarine use and marine excursions by spotted grunter Pomadasys commersonnii in the Great Fish Estuary, South Africa, were studied using manual and automated telemetry methods. In all, 20 individuals, ranging from 362 mm to 698 mm total length (TL), were caught and tagged with acousticcoded ...

  13. Marine and Estuarine Ecology. Man and the Gulf of Mexico.

    Science.gov (United States)

    Irby, Bobby N.; And Others

    "Man and the Gulf of Mexico (MGM)" is a marine science curriculum developed to meet the marine science needs of tenth through twelfth grade students in Mississippi and Alabama schools. This MGM unit, which focuses on marine and estuarine ecology, is divided into six sections. The first section contains unit objectives, discussions of the…

  14. Lead distribution in coastal and estuarine sediments around India

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, S.; Chakraborty, P.; Nath, B.N.

    in estuarine sediments near Cua Ong harbor, Ha Long Bay, Vietnam, Geologica Belgica, 13 (1-2) 37–47. Jena, M., 2008. Pollution in the Mahanadi: Urban Sewage, Industrial Effluents and Biomedical Waste. Econ. Polit. Wkly. 88–93. Jonathan, M.P., Ram-Mohan, V...

  15. Decision support handbook for recovery of contaminated inhabited areas

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, K.G. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy, Roskilde (Denmark)); Ammann, M. (STUK, Helsinki (Finland)); Backe, S. (IFE, Kjeller (Norway)); Rosen, K. (Swedish Univ. of Agricultural Sciences, Uppsala (Sweden))

    2008-07-15

    The handbook is aimed at providing Nordic decision-makers and their expert advisors with required background material for the development of an optimised, operational preparedness for situations where airborne radioactive matter has contaminated a Nordic inhabited area. The focus is on the mitigation of long-term problems. It should be stressed that the information given in the handbook is comprehensive, and many details require careful consideration well in time before implementation of countermeasures in a specific area. Training sessions are therefore recommended. The handbook describes the current relevant Nordic preparedness (dissemination routes) in detail, and suggests methods for measurement of contamination and prognoses of resultant doses, and data for evaluation of countermeasures and associated waste management options. A number of non-technical aspects of contamination in inhabited areas, and of countermeasures for its mitigation, are discussed, and a series of recommendations on the application of all the handbook data in a holistic countermeasure strategy are given. A part of the handbook development has been a dialogue with end-user representatives in each of the Nordic countries, to focus the work of the specific needs of the users. (au)

  16. Decision support handbook for recovery of contaminated inhabited areas

    International Nuclear Information System (INIS)

    Andersson, K.G.; Ammann, M.; Backe, S.; Rosen, K.

    2008-07-01

    The handbook is aimed at providing Nordic decision-makers and their expert advisors with required background material for the development of an optimised, operational preparedness for situations where airborne radioactive matter has contaminated a Nordic inhabited area. The focus is on the mitigation of long-term problems. It should be stressed that the information given in the handbook is comprehensive, and many details require careful consideration well in time before implementation of countermeasures in a specific area. Training sessions are therefore recommended. The handbook describes the current relevant Nordic preparedness (dissemination routes) in detail, and suggests methods for measurement of contamination and prognoses of resultant doses, and data for evaluation of countermeasures and associated waste management options. A number of non-technical aspects of contamination in inhabited areas, and of countermeasures for its mitigation, are discussed, and a series of recommendations on the application of all the handbook data in a holistic countermeasure strategy are given. A part of the handbook development has been a dialogue with end-user representatives in each of the Nordic countries, to focus the work of the specific needs of the users. (au)

  17. Cytogenetic study of murine rodents inhabiting in uranium-mining regions of Akmolinskaya oblast

    International Nuclear Information System (INIS)

    Kazymbet, P.; Altaeva, N.; Bakhtin, M.; Zhapbasov, R.

    2010-01-01

    Republic of Kazakhstan is ranked as the world's leading uranium ore reserves. About 25% of the world's proven uranium ore reserves occur here. Strategy of study concerning ecology effects conditioned by ionizing radiation includes as one main element an analysis of genetic processes in natural populations and ecosystems. Therefore analysis of cytogenetic effects of murine rodents inhabiting in influence zones of uranium-mining regions is one of the most important elements of radio-bio-ecological monitoring and are not completed so far. In habitat of murine rodents in influence zone of Stepnogorsk Mining-Chemical Complex tailing it is shown that gamma radiation equivalent dose rate and beta-particle flux density exceed from 6 to 15 times check measurements. In soil, plant, and water samples the activity of radionuclides like 238 U, 226 Ra, 232 Th and 210 Pb exceeds the testing level from 2 to 52 times. Dose of ionizing radiation absorbed by murine rodents inhabited in radioactive contaminated areas exceeds from 10 to 19 times the one absorbed by control animals. Big Jerboa (Allactaga major Kern) inhabited nearby of Stepnogorsk Mining-Chemical Complex tailing has rate of occurrence of cells with hypo diploidy, and hyper diploidy in hematopoietic tissue which correspondingly 1,85 and 3,5 times exceeds the control level; and this factor of Jerboa (Allactaga saltator Eversman) is correspondingly 1,7 and 4,1 times higher than control level. Rate of occurrence of cells with polyploidy in Big Jerboa (Allactaga major Kern) from radioactively contaminated areas is 2,7 times higher than in control animal; and this factor of Jerboa (Allactaga saltator Eversman) by 6,4 times exceeds control level. Levels of chromosomal rearrangements of Big Jerboa (Allactaga major Kern) from trail and control areas are 3,39±0,60% and 0,60±0,19% correspondently; and these factors of Jerboa (Allactaga saltator Eversman) are 4,63±0,91% and 1,22±0,37%, correspondently which confirms existence

  18. Modeling the dispersion of endocrine disruptors in the Santos Estuarine System (Sao Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Giovana Teixeira Gimiliani

    2016-03-01

    Full Text Available Abstract Estrogens are hormones responsible for growth and reproduction. They are naturally synthesized by animals and humans alike. Xenoestrogens are identical to natural hormones, but they are man-made and used as oral contraceptives. Xenoestrogens are a specific group of drugs found in domestic wastewater and some environmental matrices. These compounds remain after conventional sewage treatment and, consequently, affect both the environment and non-target aquatic organisms. In this study, we used the Delft3D hydrodynamic model to estimate the amount of both natural and synthetic estrogens that have been released in the Estuarine System of Santos and São Vicente and the Santos Bay. The data on flow from the sewage treatment plants and on average concentrations of natural and synthetic estrogens released in aquatic environments were obtained from the literature. The results of the modeling showed higher concentrations of estrogens in the estuarine waters of the Largo Pompeba region, the São Vicente Canal, and the Santos Bay, which are regions that receive greater inflows of domestic sewage. The results also suggest that higher concentrations of estrogenic compounds are expected to be found in areas with higher levels of salinity.

  19. Short-term stability of estuarine benthic assemblages: are storms pattern-defining events?

    Directory of Open Access Journals (Sweden)

    Orlei A. Negrello Filho

    2013-06-01

    Full Text Available Storms, associated with strong winds and heavy rains, are often the most severe physical disturbances in shallow coastal areas causing instability to sedimentary environments. We hypothesized herein that if storms influence short-term assemblage structure of macrofauna, then assemblages should change after storms, while remaining relatively stable over calm weather conditions. The study was conducted at the subtropical Paranaguá Bay, in southern Brazil. We selected four 700 m² sites, at the estuarine outlet, to monitor changes in number of species, number of individuals and Shannon diversity. Sampling was arranged considering the weather forecast so that both before and after conditions could be recorded. Data of each site was tested separately to access the significance of specific (before/after comparisons using t tests. There were no clear effects of storms on macrofaunal species richness, abundance and diversity at the four sampled sites. Conversely, we showed that short-term variation in abundances occurred regardless of weather conditions. Increased dispersal may be the most common process associated with storms instead of mortality. Storms that intermittently affect the southern coast of Brazil can be thus seen as minor driving forces of shallow-water estuarine macrofauna. Effects of extreme meteorological events remain to be assessed.

  20. Growth and decline of shoreline industry in Sydney estuary (Australia) and influence on adjacent estuarine sediments.

    Science.gov (United States)

    Birch, G F; Lean, J; Gunns, T

    2015-06-01

    Sydney estuary (Australia), like many urbanised waterways, is degraded due to an extended history of anthropogenic activity. Two major sources of contamination to this estuary are discharge by former shoreline industries and historic and contemporary catchment stormwater. The objectives of the present study were to document changes in shoreline land use from European settlement to the present day and determine the influence of this trend on the metal content of adjacent estuarine sediments. Temporal analysis of land use for seven time horizons between 1788 and 2010 showed rapid expansion of industry along much of the Sydney estuary foreshore soon after European settlement due to the benefits of easy and inexpensive access and readily available water for cooling and power. Shoreline industry attained maximum development in 1978 (32-km length) and declined rapidly to the present-day (9-km length) through redevelopment of industrial sites into medium- to high-density, high-value residential housing. Cores taken adjacent to 11 long-term industrial sites showed that past industrial practices contributed significantly to contamination of estuarine sediment. Subsurface metal concentrations were up to 35 times that of present-day surface sediment and over 100 times greater than natural background concentrations. Sedimentation rates for areas adjacent to shoreline industry were between 0.6 and 2.5 cm/year, and relaxation times were estimated at 50 to 100 years. Natural relaxation and non-disturbance of sediments may be the best management practice in most locations.

  1. The importance of ecosystem services for rural inhabitants in a changing cultural landscape in Romania

    Directory of Open Access Journals (Sweden)

    Tibor Hartel

    2014-06-01

    Full Text Available Many traditional cultural landscapes evolved as coupled social-ecological systems. It is important to understand how such systems navigate novel challenges posed by globalization. To address this issue, we bring together two components of a pilot study carried out in a cultural landscape from Central Romania. The region was affected by major social and economic perturbations in the past century, affecting ethnic composition, community cohesion, land property regimes, and the management of common resources. The first component of our study investigated how rural inhabitants appreciated ecosystem services through questionnaires with 98 people in 30 villages. The second component aimed to assess the perception of people about ongoing changes in their communities through semistructured interviews with 50 people in 5 villages. Rural inhabitants particularly valued provisioning ecosystem services such as firewood, water, and crops, but also healthy soils. Rural communities were characterized by a number of social and economic issues, especially individualism, lack of trust, corruption, and poverty. People from communities with many initiatives, e.g., NGOs, associations, and active individuals, were more optimistic regarding the future of their communities than people from villages with few or no initiatives. A major challenge for cultural landscapes such as those in Central Romania is to find new, meaningful ways to keep the social and ecological systems connected. Otherwise there is a risk that (short-term socioeconomic interests may impair the provisioning of important ecosystem services.

  2. Patterns of Cryptosporidium oocyst shedding by eastern grey kangaroos inhabiting an Australian watershed.

    Science.gov (United States)

    Power, Michelle L; Sangster, Nicholas C; Slade, Martin B; Veal, Duncan A

    2005-10-01

    The occurrence of Cryptosporidium oocysts in feces from a population of wild eastern grey kangaroos inhabiting a protected watershed in Sydney, Australia, was investigated. Over a 2-year period, Cryptosporidium oocysts were detected in 239 of the 3,557 (6.7%) eastern grey kangaroo fecal samples tested by using a combined immunomagnetic separation and flow cytometric technique. The prevalence of Cryptosporidium in this host population was estimated to range from 0.32% to 28.5%, with peaks occurring during the autumn months. Oocyst shedding intensity ranged from below 20 oocysts/g feces to 2.0 x 10(6) oocysts/g feces, and shedding did not appear to be associated with diarrhea. Although morphologically similar to the human-infective Cryptosporidium hominis and the Cryptosporidium parvum "bovine" genotype oocysts, the oocysts isolated from kangaroo feces were identified as the Cryptosporidium "marsupial" genotype I or "marsupial" genotype II. Kangaroos are the predominant large mammal inhabiting Australian watersheds and are potentially a significant source of Cryptosporidium contamination of drinking water reservoirs. However, this host population was predominantly shedding the marsupial-derived genotypes, which to date have been identified only in marsupial host species.

  3. Abundance and Diversity of Mould Inhabiting Muara Layang Estuary Sediment, Bangka Belitung Islands

    Directory of Open Access Journals (Sweden)

    MUHAMMAD ILYAS

    2009-04-01

    Full Text Available Estuary basin is a fertile area which has important role for sustaining many organisms from estuary and sea. Mould and other saprobic microorganisms have important role to decomposing organic material in estuary water. A study on diversity and abundance of mould inhabiting Muara Layang estuary sediment, Bangka Belitung Islands has not conduct before. The objective of this study is to investigate the abundance and diversity of mould inhabiting Muara Layang estuary sediment, Bangka Belitung Islands. The mould isolation was based on sample dilution method with Rose Bengal Cloramphenicol Agar mould isolation media. The abundance of mould was counted by measuring the average Colony Forming Unit (CFU/ml of all mould colonies which grown on isolation media by Total Plate Count (TPC method. The diversity of isolated mould was identified based on phenotypic characters by observing both of macroscopic and microscopic mould morphology. The result showed that the growth average of mould colonies is about (5-27.5 x102 CFU/mL. The result of mould identification showed that eight mould genera, Aspergillus (6 species, Chaetomium, Eupenicillium (3 species, Gliocladium, Paecilomyces, Penicillium (3 species, Scopulariopsis, Trichoderma (3 species, one group identified in class level (Coelomycetes, and three groups of unidentified sterile mould isolates were isolated.

  4. The Estuarine Quality Paradox, Environmental Homeostasis and the difficulty of detecting anthropogenic stress in naturally stressed areas.

    Science.gov (United States)

    Elliott, Michael; Quintino, Victor

    2007-06-01

    Estuaries have long been regarded as environmentally naturally stressed areas because of the high degree of variability in their physico-chemical characteristics, for example oxygen, temperature and salinity in the water column and bed sediment dynamics. However, their biota is well-adapted to cope with that stress and so the areas may be regarded as resilient because of that inherent variability; their ability to absorb stress without adverse effects is regarded here as Environmental Homeostasis. Hence these areas may only be regarded as stressful for marine or freshwater-adapted organisms and that for estuarine organisms this environmental stress is regarded as a subsidy whereby they successfully capitalise on the stressful conditions. In addition, using examples of the estuarine fauna and flora, this article indicates that the characteristics of natural stress in estuaries are similar to those for anthropogenic stress. An over-reliance on ecosystem structural features, such as diversity, in quality indicators therefore makes the detection of the anthropogenic stress more difficult. This difficulty is termed the Estuarine Quality Paradox. Because of these difficulties, the article argues that functional characteristics either as well as or rather than structural ones should be used in detecting environmental perturbations in estuaries.

  5. Long-term fluctuations in population of Semibalanus balanoides (L. (Crustacea in the estuarine zone of the Kola Bay

    Directory of Open Access Journals (Sweden)

    Svitina V. S.

    2017-06-01

    Full Text Available The intertidal population of the barnacles Semibalanus balanoides has been explored in the estuarine zone of the Tuloma River at the end of the Kola Bay for the first time. Barnacles S. balanoides are typical species for the littoral zone of the northern seas, they populate both the high and low salinity areas along the coast of the Barents Sea. The ecology and distribution of barnacle population in estuarine intertidal zones of the Barents Sea are not studied previously, and under the critical salinity conditions of any estuary, in particular. The investigation have been carried out on the littoral of the western (left shore of the southern tribe of the Kola Bay – the estuary section from the Tuloma bridge to the Cape Elovy. The studied site is a sandy-boulder beach with stony bars, its length is about 1 150 m, the area is about 126 500 m2. Counting the number of S. balanoides in clusters has been performed on site (without removal of the copepods from the population by the standard method for intertidal sampling. Simultaneously with the defining the number of barnacles for the period 2003–2014, the measurements of salinity and temperature of water and air have been made. The peculiarity of the estuarine barnacle population is their complete absence in the upper horizon of the littoral, and in the middle and the lower horizons they are found only within the channels of the littoral streams (3–20 specimens in the sample. For the first time the abundance and biomass of barnacles S. balanoides in this estuarine population has been determined, and the causes of their narrow-local distribution on the estuary littoral of the Tuloma River have been revealed. The main ecological factors determining the abundance and specific distribution of barnacles under the conditions of estuarine littoral have been established. The regular increase in the density of adult S. balanoides settlements along the gradient of water salinity from the Tuloma River to

  6. Impacts of Biomass Burning on African Climate and Inhabitants

    Science.gov (United States)

    Ajoku, O.; Burney, J. A.; Miller, A. J.

    2017-12-01

    It has been well documented that aerosols, particulate matter in the atmosphere, created from biomass burning have an effect on regional weather patterns. These aerosols, known as black carbon (BC), are rather damaging to human health and have been documented as the cause of many fatalities where wood burning is a common practice. Our research focuses on the hemispherical transport of BC during monsoon months and its effect on precipitation in addition to gaining a better understanding of the effects of BC caused by human induced fires on health related casualities. Early analysis shows that BC undergoing hemispherical transport alter monsoon dynamics in the month of July. In addition, the most human induced fires occur during boreal autumn, and thus these months have the most potential for human induced fatalities. For a broader impact, there are more than 200 million inhabitants that lay in the path of BC both at the source region and areas these aerosols are advected to.

  7. Biomonitoring a human population inhabiting nearby a deactivated uranium mine

    International Nuclear Information System (INIS)

    Lourenço, J.; Pereira, R.; Pinto, F.; Caetano, T.; Silva, A.; Carvalheiro, T.

    2013-01-01

    Highlights: ► Human population environmentally exposed to uranium mining wastes. ► Significantly higher levels of manganese and uranium in peripheral blood samples. ► Significant DNA damages detected by the comet assay. ► Significant decrease of NK and T lymphocytes counts in exposed individuals. ► Concerns on the risks of human populations living nearby uranium mining areas. - Abstract: Environmental exposure to uranium and its daughter radionuclides, has been linked to several negative effects such as those related with important physiological processes, like hematopoiesis, and may also be associated with genotoxicity effects. Herein, genotoxic effects, immunotoxicity, trace elements and C reactive protein (CRP) analyses, were performed in peripheral blood samples collected from individuals of a population living near a deactivated uranium mine. C reactive protein analysis was performed to exclude candidates with active inflammatory processes from further evaluations. DNA damage and immunotoxicity (immunophenotyping and immune cell counts) were evaluated by comet assay and flow cytometry, respectively. Significant DNA damage was observed in the peripheral blood samples from volunteers living in the Cunha Baixa village. A significant decrease of NK and T lymphocytes counts were observed in the individuals from the Cunha Baixa village, when compared with individuals from the reference site. Uranium and manganese levels were significantly higher in the Cunha Baixa village inhabitants. On the other hand, zinc levels were significantly lower in those individuals when compared with the volunteers from the control village. Results suggest that inhabitants from Cunha Baixa have a higher risk of suffering from serious diseases such as cancer, since high DNA damages were observed in peripheral blood leukocytes and also decreased levels of NK and T cells, which play an essential role in the defense against tumor growth

  8. EURANOS. Generic handbook for assisting in the management of contaminated inhabited areas in Europe following a radiological emergency

    DEFF Research Database (Denmark)

    Nisbet, A.F.; Andersson, Kasper Grann; Brown, J.

    The handbook for inhabited areas has been developed as a result of a series of European and UK initiatives that started in the early 1990s. It is aimed at national and local authorities, central government departments and agencies, radiation protection experts, emergency services, the water...... in the early and medium-longer term phases of an incident. Sources of contamination considered in the handbook are nuclear accidents, radiological dispersion devices and satellite accidents. Inhabited areas are characterised by a number of different surfaces i.e. buildings; roads and paved areas; soils, grass...... non-crisis conditions to engage stakeholders and to develop local and regional plans. The handbook can be applied as part of the decision-aiding process to develop a recovery strategy following an incident. In addition, the handbook is useful for training purposes and during emergency exercises...

  9. Developing a salinity-based approach for the evaluation of DIN removal rate in estuarine ecosystems.

    Science.gov (United States)

    Hong, Yiguo; Wang, Shuailong; Xu, Xiang-Rong; Wu, Jiapeng; Liu, Ling; Yue, Weizhong; Wu, Meilin; Wang, Youshao

    2015-10-01

    Estuaries play an important role in the removal of overloading nitrogen to relieve the eutrophic pressure of coastal seawater. However, the exact amount of nitrogen removed in estuarine ecosystems is difficult to be estimated because of the complex dynamic mixing process between riverine water and coastal seawater. In this study, a new method was developed to calculate the removal rate of dissolved inorganic nitrogen (DIN) in estuarine waters attributed to the mixing process and was based on the assumption that relative salinity can serve as an indicator of the degree of mixing. This assumption was supported by the experimental results that demonstrated a linear regression relationship between DIN decline and salinity increase Thus, the decreased amount of DIN in mixing waters attributed to the dilution effect could be determined with the salinity as an index. With this model, the DIN removal rate in both Chesapeake Bay and Pearl River Estuary were defined. As predicted, our analysis demonstrated that the DIN removal rate increased gradually from upstream to downstream in both studied estuaries with obvious seasonable variation pattern: high in warm seasons and low in cold seasons. The practical application of this method might be affected by multiple factors, including the geographic landform of estuaries, initial estuaries DIN concentration, the DIN concentration in seawater, DIN importing from tributaries, sewage discharge and hydrodynamic mixing. Therefore, the results supported the hypothesis that estuaries have a strong capability to remove the nitrogen inputted from human activities, especially in warm season and therefore should play an important role in regulating the balance of global nitrogen biogeochemical cycle.

  10. A General Solution for Groundwater Flow in Estuarine Leaky Aquifer System with Considering Aquifer Anisotropy

    Science.gov (United States)

    Chen, Po-Chia; Chuang, Mo-Hsiung; Tan, Yih-Chi

    2014-05-01

    In recent years the urban and industrial developments near the coastal area are rapid and therefore the associated population grows dramatically. More and more water demand for human activities, agriculture irrigation, and aquaculture relies on heavy pumping in coastal area. The decline of groundwater table may result in the problems of seawater intrusion and/or land subsidence. Since the 1950s, numerous studies focused on the effect of tidal fluctuation on the groundwater flow in the coastal area. Many studies concentrated on the developments of one-dimensional (1D) and two-dimensional (2D) analytical solutions describing the tide-induced head fluctuations. For example, Jacob (1950) derived an analytical solution of 1D groundwater flow in a confined aquifer with a boundary condition subject to sinusoidal oscillation. Jiao and Tang (1999) derived a 1D analytical solution of a leaky confined aquifer by considered a constant groundwater head in the overlying unconfined aquifer. Jeng et al. (2002) studied the tidal propagation in a coupled unconfined and confined costal aquifer system. Sun (1997) presented a 2D solution for groundwater response to tidal loading in an estuary. Tang and Jiao (2001) derived a 2D analytical solution in a leaky confined aquifer system near open tidal water. This study aims at developing a general analytical solution describing the head fluctuations in a 2D estuarine aquifer system consisted of an unconfined aquifer, a confined aquifer, and an aquitard between them. Both the confined and unconfined aquifers are considered to be anisotropic. The predicted head fluctuations from this solution will compare with the simulation results from the MODFLOW program. In addition, the solutions mentioned above will be shown to be special cases of the present solution. Some hypothetical cases regarding the head fluctuation in costal aquifers will be made to investigate the dynamic effects of water table fluctuation, hydrogeological conditions, and

  11. Long-term observation of amphibian populations inhabiting urban and forested areas in Yekaterinburg, Russia

    Science.gov (United States)

    Vershinin, Vladimir L.; Vershinina, Svetlana D.; Berzin, Dmitry L.; Zmeeva, Darya V.; Kinev, Alexander V.

    2015-05-01

    This article presents data derived from a 36 year-long uninterrupted observational study of amphibian populations living in the city and vicinity of Yekaterinburg, Russia. This area is inhabited by six amphibian species. Based on a degree of anthropogenic transformation, the urban territory is divided into five highly mosaic zones characterized by vegetation, temperature, and a distinctive water pollution profile. Population data is presented year-by-year for the number of animals, sex ratio, and species-specific fecundity including the number and quality of spawns for the following amphibian species: Salamandrella keyserligii, Rana arvalis, R. temporaria, Lissotriton vulgaris, and Pelophylax ridibundus. These data provide an excellent opportunity to assess an urban environment from an animal population-wide perspective, as well as revealing the forces driving animal adaptation to the anthropogenic transformation of habitats.

  12. Identification of largemouth bass virus in the introduced Northern Snakehead inhabiting the Chesapeake Bay watershed.

    Science.gov (United States)

    Iwanowicz, L; Densmore, C; Hahn, C; McAllister, P; Odenkirk, J

    2013-09-01

    The Northern Snakehead Channa argus is an introduced species that now inhabits the Chesapeake Bay. During a preliminary survey for introduced pathogens possibly harbored by these fish in Virginia waters, a filterable agent was isolated from five specimens that produced cytopathic effects in BF-2 cells. Based on PCR amplification and partial sequencing of the major capsid protein (MCP), DNA polymerase (DNApol), and DNA methyltransferase (Mtase) genes, the isolates were identified as Largemouth Bass virus (LMBV). Nucleotide sequences of the MCP (492 bp) and DNApol (419 pb) genes were 100% identical to those of LMBV. The nucleotide sequence of the Mtase (206 bp) gene was 99.5% identical to that of LMBV, and the single nucleotide substitution did not lead to a predicted amino acid coding change. This is the first report of LMBV from the Northern Snakehead, and provides evidence that noncentrarchid fishes may be susceptible to this virus.

  13. Identification of largemouth bass virus in the introduced Northern snakehead inhabiting the Cheasapeake Bay watershed

    Science.gov (United States)

    Iwanowicz, Luke R.; Densmore, Christine L.; Hahn, Cassidy M.; McAllister, Phillip; Odenkirk, John

    2013-01-01

    The Northern Snakehead Channa argus is an introduced species that now inhabits the Chesapeake Bay. During a preliminary survey for introduced pathogens possibly harbored by these fish in Virginia waters, a filterable agent was isolated from five specimens that produced cytopathic effects in BF-2 cells. Based on PCR amplification and partial sequencing of the major capsid protein (MCP), DNA polymerase (DNApol), and DNA methyltransferase (Mtase) genes, the isolates were identified as Largemouth Bass virus (LMBV). Nucleotide sequences of the MCP (492 bp) and DNApol (419 pb) genes were 100% identical to those of LMBV. The nucleotide sequence of the Mtase (206 bp) gene was 99.5% identical to that of LMBV, and the single nucleotide substitution did not lead to a predicted amino acid coding change. This is the first report of LMBV from the Northern Snakehead, and provides evidence that noncentrarchid fishes may be susceptible to this virus.

  14. Sulfate-reducing bacteria inhabiting natural corrosion deposits from marine steel structures.

    Science.gov (United States)

    Païssé, Sandrine; Ghiglione, Jean-François; Marty, Florence; Abbas, Ben; Gueuné, Hervé; Amaya, José Maria Sanchez; Muyzer, Gerard; Quillet, Laurent

    2013-08-01

    In the present study, investigations were conducted on natural corrosion deposits to better understand the role of sulfate-reducing bacteria (SRB) in the accelerated corrosion process of carbon steel sheet piles in port environments. We describe the abundance and diversity of total and metabolically active SRB within five natural corrosion deposits located within tidal or low water zone and showing either normal or accelerated corrosion. By using molecular techniques, such as quantitative real-time polymerase chain reaction, denaturing gel gradient electrophoresis, and sequence cloning based on 16S rRNA, dsrB genes, and their transcripts, we demonstrated a clear distinction between SRB population structure inhabiting normal or accelerated low-water corrosion deposits. Although SRB were present in both normal and accelerated low-water corrosion deposits, they dominated and were exclusively active in the inner and intermediate layers of accelerated corrosion deposits. We also highlighted that some of these SRB populations are specific to the accelerated low-water corrosion deposit environment in which they probably play a dominant role in the sulfured corrosion product enrichment.

  15. Methodology for impact assessment in the estuarine/marine environment

    International Nuclear Information System (INIS)

    Haven, K.F.

    1975-01-01

    Impacts on the estuarine/marine environment can be assessed in economic terms by tracing the impact flow out of the economic sector through the marine environment and back into the economic sector as changes in natural resource availability. An impact can then be measured by the changes created in the economic sector by changes in resource availability. Primary emphasis is placed on the development of an appropriate ecological model of the estuarine environment for this purpose. Two types, an ecological input/output model and a dynamic (difference equation) model, are proposed. Acceptability criteria for these models include the ability to track lethal and sublethal, direct and indirect (food web), and short- and long-term effects of a variety of pollutants related to the production and use of various energy resources

  16. Marine and estuarine natural microbial biofilms: ecological and biogeochemical dimensions

    Directory of Open Access Journals (Sweden)

    O. Roger Anderson

    2016-08-01

    Full Text Available Marine and estuarine microbial biofilms are ubiquitously distributed worldwide and are increasingly of interest in basic and applied sciences because of their unique structural and functional features that make them remarkably different from the biota in the plankton. This is a review of some current scientific knowledge of naturally occurring microbial marine and estuarine biofilms including prokaryotic and microeukaryotic biota, but excluding research specifically on engineering and applied aspects of biofilms such as biofouling. Because the microbial communities including bacteria and protists are integral to the fundamental ecological and biogeochemical processes that support biofilm communities, particular attention is given to the structural and ecological aspects of microbial biofilm formation, succession, and maturation, as well as the dynamics of the interactions of the microbiota in biofilms. The intent is to highlight current state of scientific knowledge and possible avenues of future productive research, especially focusing on the ecological and biogeochemical dimensions.

  17. Defense Coastal/Estuarine Research Program (DCERP1)

    Science.gov (United States)

    2013-05-10

    Davenport. 2006. The impact of tourism and personal leisure transport on coastal environments: A review. Estuarine, Coastal and Shelf Science 67:280–292... volunteers during high-use periods (on weekends and especially during holiday weekends) for educational outreach and to monitor critical foraging areas might...could be implemented that might be more effective. For example, interns or volunteers could be used during high-use periods (i.e., on summer weekends

  18. Paradigms in the Recovery of Estuarine and Coastal Ecosystems

    OpenAIRE

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

    2015-01-01

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

  19. Sea-Level Rise: Estuarine Wetlands of Mustang Island at Imminent Risk of Submergence

    Science.gov (United States)

    Radosavljevic, B.; Gibeaut, J.; Tissot, P.

    2012-04-01

    Coastal areas in Texas are vulnerable to sea-level rise (SLR) because of high rates of land subsidence and flat topography. Estuarine wetlands in particular, are highly threatened by SLR because the small tidal range limits their vertical distribution. In order to offset wetland submergence induced by SLR, the rate of vertical accretion must at least equal the rate of SLR. To investigate wetland susceptibility to SLR-driven submergence, accretion rates in different wetland environments of Mustang Island (MUI), Texas, were determined using a Cesium-137 marker horizon technique. Comparisons of relative volumetric contributions of mineral and organic matter to accretion were made, as well. Mustang Island is located in the Coastal Bend of the south-central Texas coast, bounded by the waters of the Gulf of Mexico and Corpus Christi Bay. The tide range in Texas bays and estuaries is small (

  20. Tracing estuarine organic matter sources into the southern North Sea using C and N isotopic signatures

    DEFF Research Database (Denmark)

    Bristow, Laura A.; Jickells, Timothy D.; Weston, Keith

    2013-01-01

    organic matter pool offshore out of the estuaries. These results indicate that estuarine derived organic matter from marsh plants, seagrasses and/or macroalgae contributes to the southern North Sea organic matter pool and is therefore likely to contribute to winter-time shelf sea carbon and nitrogen......Sources and distribution of particulate organic matter in surface waters of the Humber and Thames estuaries and in the East Anglian plume in the southern North Sea were investigated in winter 2006/2007. Carbon (C) and nitrogen (N) stable isotopes provided evidence for the presence of three......Euro degrees) and elevated C:N ratio (> 12.7). Particulate organic matter with enriched C-13 values were observed throughout the Humber estuary and at the marine end-member of the Thames estuary. While bacterial cycling of organic carbon undoubtedly takes place within these estuaries, these processes...

  1. Managing bay and estuarine ecosystems for multiple services

    Science.gov (United States)

    Needles, Lisa A.; Lester, Sarah E.; Ambrose, Richard; Andren, Anders; Beyeler, Marc; Connor, Michael S.; Eckman, James E.; Costa-Pierce, Barry A.; Gaines, Steven D.; Lafferty, Kevin D.; Lenihan, Junter S.; Parrish, Julia; Peterson, Mark S.; Scaroni, Amy E.; Weis, Judith S.; Wendt, Dean E.

    2013-01-01

    Managers are moving from a model of managing individual sectors, human activities, or ecosystem services to an ecosystem-based management (EBM) approach which attempts to balance the range of services provided by ecosystems. Applying EBM is often difficult due to inherent tradeoffs in managing for different services. This challenge particularly holds for estuarine systems, which have been heavily altered in most regions and are often subject to intense management interventions. Estuarine managers can often choose among a range of management tactics to enhance a particular service; although some management actions will result in strong tradeoffs, others may enhance multiple services simultaneously. Management of estuarine ecosystems could be improved by distinguishing between optimal management actions for enhancing multiple services and those that have severe tradeoffs. This requires a framework that evaluates tradeoff scenarios and identifies management actions likely to benefit multiple services. We created a management action-services matrix as a first step towards assessing tradeoffs and providing managers with a decision support tool. We found that management actions that restored or enhanced natural vegetation (e.g., salt marsh and mangroves) and some shellfish (particularly oysters and oyster reef habitat) benefited multiple services. In contrast, management actions such as desalination, salt pond creation, sand mining, and large container shipping had large net negative effects on several of the other services considered in the matrix. Our framework provides resource managers a simple way to inform EBM decisions and can also be used as a first step in more sophisticated approaches that model service delivery.

  2. Progress and challenges in coupled hydrodynamic-ecological estuarine modeling.

    Science.gov (United States)

    Ganju, Neil K; Brush, Mark J; Rashleigh, Brenda; Aretxabaleta, Alfredo L; Del Barrio, Pilar; Grear, Jason S; Harris, Lora A; Lake, Samuel J; McCardell, Grant; O'Donnell, James; Ralston, David K; Signell, Richard P; Testa, Jeremy M; Vaudrey, Jamie M P

    2016-03-01

    Numerical modeling has emerged over the last several decades as a widely accepted tool for investigations in environmental sciences. In estuarine research, hydrodynamic and ecological models have moved along parallel tracks with regard to complexity, refinement, computational power, and incorporation of uncertainty. Coupled hydrodynamic-ecological models have been used to assess ecosystem processes and interactions, simulate future scenarios, and evaluate remedial actions in response to eutrophication, habitat loss, and freshwater diversion. The need to couple hydrodynamic and ecological models to address research and management questions is clear, because dynamic feedbacks between biotic and physical processes are critical interactions within ecosystems. In this review we present historical and modern perspectives on estuarine hydrodynamic and ecological modeling, consider model limitations, and address aspects of model linkage, skill assessment, and complexity. We discuss the balance between spatial and temporal resolution and present examples using different spatiotemporal scales. Finally, we recommend future lines of inquiry, approaches to balance complexity and uncertainty, and model transparency and utility. It is idealistic to think we can pursue a "theory of everything" for estuarine models, but recent advances suggest that models for both scientific investigations and management applications will continue to improve in terms of realism, precision, and accuracy.

  3. Anaerobic ammonium oxidation in an estuarine sediment

    NARCIS (Netherlands)

    Risgaard-Petersen, N.; Meyer, R.L.; Schmid, M.C.; Jetten, M.S.M.; Enrich-Prast, A.; Rysgaard, S.; Revsbech, N.P.

    2004-01-01

    The occurrence and significance of the anammox (anaerobic ammonium oxidation) process relative to denitrification was studied in photosynthetically active sediment from 2 shallow-water estuaries: Randers Fjord and Norsminde Fjord, Denmark. Anammox accounted for 5 to 24 % of N-2 production in Randers

  4. Anaerobic ammonium oxidation in an estuarine sediment

    NARCIS (Netherlands)

    Risgaard-Petersen, N.; Meyer, R.L.; Schmid, M.; Jetten, M.S.M.; Enrich-Prast, A.; Rysgaard, S.; Revsbech, N.P.

    2004-01-01

    The occurrence and significance of the anammox (anaerobic ammonium oxidation) process relative to denitrification was studied in photosynthetically active sediment from 2 shallow-water estuaries: Randers Fjord and Norsminde Fjord, Denmark. Anammox accounted for 5 to 24% of N2 production in Randers

  5. Residual fluxes of water, salt and suspended sediment in the Beypore Estuary

    Digital Repository Service at National Institute of Oceanography (India)

    AnilKumar, N.; Revichandran, C.; Sankaranarayanan, V.N.; Josanto, V.

    The monthly trends of the residual fluxes of salt and water and the transportation of suspended sediments in the Beypore estuarine system, Kerala, India were examined. At the river mouth the water flux was directed seaward during the postmonsoon...

  6. Reactive iron and manganese in estuarine sediments of the Baltic Sea: Impacts of flocculation and redox shuttling

    Science.gov (United States)

    Jilbert, Tom; Tiihonen, Rosa; Myllykangas, Jukka-Pekka; Asmala, Eero; Hietanen, Susanna

    2016-04-01

    Iron (Fe) and manganese (Mn) play important roles in sedimentary carbon cycling in both freshwater and marine systems. Dissimilatory reduction of Fe and Mn oxides is known to be a major pathway of suboxic organic matter remineralization in surface sediments, while recent studies have shown that Fe and Mn oxides may be involved in the anaerobic oxidation of methane deeper in the sediment column (e.g., Egger et al., 2015). Estuaries are transitional environments, characterized by gradients of salinity and redox conditions which impact on the mobility of Fe and Mn. In turn, the distribution of Fe and Mn in estuarine sediments, and the role of the two metals in carbon cycling, is expected to be spatially heterogeneous. However, few studies have attempted to describe the sedimentary distribution of Fe and Mn in the context of processes occurring in the estuarine water column. In particular, salinity-driven flocculation and redox shuttling are two key processes whose relative impacts on sedimentary Fe and Mn have not been clearly demonstrated. In this study we investigated the coupled water column and sedimentary cycling of Fe and Mn along a 60km non-tidal estuarine transect in the Gulf of Finland, Baltic Sea. We show that riverine Fe entering the estuary as colloidal oxides associated with dissolved organic matter (DOM) is quickly flocculated and sedimented within 5 km of the river mouth, despite the shallow lateral salinity gradient. Sediments within this range are enriched in Fe (up to twice the regional average), principally in the form of crystalline Fe oxides as determined by sequential extractions. The high crystallinity implies relative maturity of the oxide mineralogy, likely due to sustained oxic conditions and long residence time in the river catchment. Despite the reducing conditions below the sediment-water interface, Fe is largely retained in the sediments close to the river mouth. In contrast, sedimentary Mn concentrations are highest in a deep silled

  7. REE in suspended particulate matter and sediment of the Zuari estuary and adjacent shelf, western India: Influence of mining and estuarine turbidity

    Digital Repository Service at National Institute of Oceanography (India)

    Shynu, R.; Rao, V.P.; Parthiban, G.; Balakrishnan, S.; Narvekar, T.; Kessarkar, P.M.

    , salt-induced coagulation of river organic colloids, adsorption-desorption reactions, remobilization due to early diagenetic changes and re-suspension (Hoyle et al., 1984). The behavior of REE in estuarine water and sediments across salinity gradient... l of water at each station, i.e., each filtration unit takes about 1.7 l of water. De-ionized water was used to clean the filters. The SPM retained on filter papers was dried and weighted. SPM is expressed as milligram per liter. Salinity...

  8. Biometry of neotropical invertebrates inhabiting floodplain rivers: unraveling bionomy

    Directory of Open Access Journals (Sweden)

    Florencia Zilli

    Full Text Available ABSTRACT Currently, it is widely recognized that invertebrates play key roles in neotropical floodplains and in many other environments worldwide. However, little information has been published concerning their biometry, in spite that it represents an essential tool for many different studies. Here, we provided length-mass and length-length relationships by fitting the linearized model (log10 Y = log10a + b log10 X and several mean biomass ratios ± SE for bivalves, gastropods, quironomids, ephemeropterans, oligochaetes and hirudineans. We measured, weighed, oven dried and incinerated to ashes specimens collected from 2005 to 2014 in the Paraná River, Argentina. The lineal equations had fit levels higher than 75% in most of the significant regressions. Hence, when slopes were compared, differences raised from ontogeny and phylogeny of taxa. Additionally, slopes resulted different from constants of other regions, types of environments and climates. In addition, organic matter ratios resulted significantly different among invertebrates according to their feeding types. The equations and ratios that we provided will facilitate future research on life history, productivity and energy transference in the food webs of invertebrates inhabiting floodplain wetlands and can be used as tools for planning management strategies and in restoration projects of aquatic environments.

  9. Hyperuricemia in the inhabitants of the Marshall Islands

    International Nuclear Information System (INIS)

    Adams, W.H.; Harper, J.A.; Heotis, P.M.; Jamner, A.H.

    1984-01-01

    Annual medical examinations are conducted by Brookhaven National Laboratory (BNL) for a population of Marshallese who were accidentally exposed to radioactive fallout in 1954, for a comparison population, and for all inhabitants of the atolls of Rongelap and Utirik. Disease surveillance includes analysis of serum samples. Elevated serum uric acid (SUA) levels are common along Pacific populations, and modifying environmental factors have been investigated as a cause for this finding. The authors have studied SUA levels of people living in the Marshall Islands, and have found elevated values similar to those reported for other Micronesian populations. The nearly Gaussian distribution of individual serum uric acid values for men, and for women less than or equal to45 years of age, indicates that the elevation is due to a regularized increase in serum uric acid rather than to a subpopulation that has pathologic hyperuricemia. The higher serum uric acid levels appear, therefore, to be normal for the Marshallese, a conclusion supported by the infrequency of clinical gout in the population tested

  10. ASSESSMENT OF NOISE POLLUTION OF INHABITED TERRITORIES IMPACTED BY AIRFIELDS

    Directory of Open Access Journals (Sweden)

    Sazonov Eduard Vladimirovich

    2012-10-01

    Full Text Available In the article, authors provide an overview of effective regulatory, reference and technical documents that govern the extent of suitability of territories adjacent to airfields for building-up. Methods of assessing the acceptable limits of the aviation noise in the areas adjacent to airfields are considered in the article. Ecologization of airfield environs is not a new problem. The research described in the article is noteworthy for the proposed optimization of any plans for the assurance of habitability of specific areas impacted by noise pollutions. The optimization consists in a set of organizational and technical solutions based on the noise levels in specific areas, development planning conditions of inhabited areas, and the monitoring of the airfield environs. It is the multi-factor approach that is capable of resolving the problem of ecological stress imposed by the noise coming from the air transport. Towards this end, the problem-solving strategy is to be developed and implemented in the areas that feature the same unfavorable environmental characteristics.

  11. External dose estimates for future Bikini Atoll inhabitants

    International Nuclear Information System (INIS)

    Gudiksen, P.H.; Crites, T.R.; Robison, W.L.

    1976-01-01

    To evaluate the potential radiation doses that may be received by the returning Bikinians, we surveyed the residual radioactivity on Bikini and Eneu Islands in June of 1975. An integral part of the survey included measurements of gamma-ray exposure rates which are used to estimate external gamma-ray doses. The survey showed that on Bikini Island the rates are highly variable: values near the shores are generally of the order of 10 to 20 μR/h, while those within the interior average about 40 μR/h with a range of roughly 30 to 100 μR/h. Eneu Island, however, is characterized by more or less uniformly distributed gamma radiation levels of less than 10 μR/h over the entire island. These data, in conjunction with population statistics and expected life styles, allowed us to estimate the potential external gamma-ray doses associated with proposed housing locations along the lagoon road and within the interior portions of Bikini Island as well as along the lagoon side of Eneu Island. As expected, living on Eneu Island results in the lowest doses: 0.12 rem during the first year and 2.9 rem during 30 years. The highest values, 0.28 rem during the first year and 5.9 rem over 30 years, may potentially be received by inhabitants living within the interior of Bikini Island. Other options under consideration produce intermediate values

  12. Dermal insecticide residues from birds inhabiting an orchard

    Science.gov (United States)

    Vyas, N.B.; Spann, J.W.; Hulse, C.S.; Gentry, S.; Borges, S.L.

    2007-01-01

    The US Environmental Protection Agency conducts risk assessments of insecticide applications to wild birds using a model that is limited to the dietary route of exposure. However, free-flying birds are also exposed to insecticides via the inhalation and dermal routes. We measured azinphos-methyl residues on the skin plus feathers and the feet of brown-headed cowbirds (Molothrus ater) in order to quantify dermal exposure to songbirds that entered and inhabited an apple (Malus x domestica) orchard following an insecticide application. Exposure to azinphos-methyl was measured by sampling birds from an aviary that was built around an apple tree. Birds sampled at 36 h and 7-day post-application were placed in the aviary within 1 h after the application whereas birds exposed for 3 days were released into the aviary 4-day post-application. Residues on vegetation and soil were also measured. Azinphos-methyl residues were detected from the skin plus feathers and the feet from all exposure periods. Our results underscore the importance of incorporating dermal exposure into avian pesticide risk assessments.

  13. Loose Coupling and Inhabited Institutions: Inclusion Policy and Teacher Strategies

    Directory of Open Access Journals (Sweden)

    Christina Deroche

    2013-07-01

    Full Text Available This case study uses interviews and participant observation to study how teachers negotiate inclusion policy in their everyday classroom interactions and strategies. Interviews consisted of two teachers and an educational assistant from one Northern Ontario classroom while participant observation was conducted for a period of seven weeks. Drawing from the framework of loose coupling and inhabited institution, this study finds that teachers actively negotiate policy in the face of classroom reality by drawing upon personal and social resources. Drawing from their previous experiences and some of their educational training they create, and implement strategies in dealing with learning diversity. Teachers felt enthusiastic about inclusion but their ideas ranged as to what it looked like; on top of their creativity in strategy making they also expressed the need for more resources and support to ensure the success of inclusion within their classrooms.

  14. Heterogeneity and Developmental Connections between Cell Types Inhabiting Teeth

    Directory of Open Access Journals (Sweden)

    Jan Krivanek

    2017-06-01

    Full Text Available Every tissue is composed of multiple cell types that are developmentally, evolutionary and functionally integrated into the unit we call an organ. Teeth, our organs for biting and mastication, are complex and made of many different cell types connected or disconnected in terms of their ontogeny. In general, epithelial and mesenchymal compartments represent the major framework of tooth formation. Thus, they give rise to the two most important matrix–producing populations: ameloblasts generating enamel and odontoblasts producing dentin. However, the real picture is far from this quite simplified view. Diverse pulp cells, the immune system, the vascular system, the innervation and cells organizing the dental follicle all interact, and jointly participate in transforming lifeless matrix into a functional organ that can sense and protect itself. Here we outline the heterogeneity of cell types that inhabit the tooth, and also provide a life history of the major populations. The mouse model system has been indispensable not only for the studies of cell lineages and heterogeneity, but also for the investigation of dental stem cells and tooth patterning during development. Finally, we briefly discuss the evolutionary aspects of cell type diversity and dental tissue integration.

  15. Two New Beggiatoa Species Inhabiting Marine Mangrove Sediments in the Caribbean

    Science.gov (United States)

    Jean, Maïtena R. N.; Gonzalez-Rizzo, Silvina; Gauffre-Autelin, Pauline; Lengger, Sabine K.; Schouten, Stefan; Gros, Olivier

    2015-01-01

    Beggiatoaceae, giant sulphur-oxidizing bacteria, are well known to occur in cold and temperate waters, as well as hydrothermal vents, where they form dense mats on the floor. However, they have never been described in tropical marine mangroves. Here, we describe two new species of benthic Beggiatoaceae colonizing a marine mangrove adjacent to mangrove roots. We combined phylogenetic and lipid analysis with electron microscopy in order to describe these organisms. Furthermore, oxygen and sulphide measurements in and ex situ were performed in a mesocosm to characterize their environment. Based on this, two new species, Candidatus Maribeggiatoa sp. and Candidatus Isobeggiatoa sp. inhabiting tropical marine mangroves in Guadeloupe were identified. The species identified as Candidatus Maribeggiatoa group suggests that this genus could harbour a third cluster with organisms ranging from 60 to 120 μm in diameter. This is also the first description of an Isobeggiatoa species outside of Arctic and temperate waters. The multiphasic approach also gives information about the environment and indications for the metabolism of these bacteria. Our study shows the widespread occurrence of members of Beggiatoaceae family and provides new insight in their potential role in shallow-water marine sulphide-rich environments such as mangroves. PMID:25689402

  16. Toward Understanding the Dynamics of Microbial Communities in an Estuarine System

    KAUST Repository

    Zhang, Weipeng

    2014-04-14

    Community assembly theories such as species sorting theory provide a framework for understanding the structures and dynamics of local communities. The effect of theoretical mechanisms can vary with the scales of observation and effects of specific environmental factors. Based on 16S rRNA gene tag pyrosequencing, different structures and temporal succession patterns were discovered between the surface sediments and bottom water microbial communities in the Pearl River Estuary (PRE). The microbial communities in the surface sediment samples were more diverse than those in the bottom water samples, and several genera were specific for the water or sediment communities. Moreover, water temperature was identified as the main variable driving community dynamics and the microbial communities in the sediment showed a greater temporal change. We speculate that nutrient-based species sorting and bacterial plasticity to the temperature contribute to the variations observed between sediment and water communities in the PRE. This study provides a more comprehensive understanding of the microbial community structures in a highly dynamic estuarine system and sheds light on the applicability of ecological theoretical mechanisms.

  17. Toward understanding the dynamics of microbial communities in an estuarine system.

    Directory of Open Access Journals (Sweden)

    Weipeng Zhang

    Full Text Available Community assembly theories such as species sorting theory provide a framework for understanding the structures and dynamics of local communities. The effect of theoretical mechanisms can vary with the scales of observation and effects of specific environmental factors. Based on 16S rRNA gene tag pyrosequencing, different structures and temporal succession patterns were discovered between the surface sediments and bottom water microbial communities in the Pearl River Estuary (PRE. The microbial communities in the surface sediment samples were more diverse than those in the bottom water samples, and several genera were specific for the water or sediment communities. Moreover, water temperature was identified as the main variable driving community dynamics and the microbial communities in the sediment showed a greater temporal change. We speculate that nutrient-based species sorting and bacterial plasticity to the temperature contribute to the variations observed between sediment and water communities in the PRE. This study provides a more comprehensive understanding of the microbial community structures in a highly dynamic estuarine system and sheds light on the applicability of ecological theoretical mechanisms.

  18. Methane emission through ebullition from an estuarine mudflat: 2. Field observations and modeling of occurrence probability

    Science.gov (United States)

    Chen, Xi; Schäfer, Karina V. R.; Slater, Lee

    2017-08-01

    Ebullition can transport methane (CH4) at a much faster rate than other pathways, albeit over limited time and area, in wetland soils and sediments. However, field observations present large uncertainties in ebullition occurrences and statistic models are needed to describe the function relationship between probability of ebullition occurrence and water level changes. A flow-through chamber was designed and installed in a mudflat of an estuarine temperate marsh. Episodic increases in CH4 concentration signaling ebullition events were observed during ebbing tides (15 events over 456 ebbing tides) and occasionally during flooding tides (4 events over 455 flooding tides). Ebullition occurrence functions were defined using logistic regression as the relative initial and end water levels, as well as tidal amplitudes were found to be the key functional variables related to ebullition events. Ebullition of methane was restricted by a surface frozen layer during winter; melting of this layer during spring thaw caused increases in CH4 concentration, with ebullition fluxes similar to those associated with large fluctuations in water level around spring tides. Our findings suggest that initial and end relative water levels, in addition to tidal amplitude, partly regulate ebullition events in tidal wetlands, modulated by the lunar cycle, storage of gas bubbles at different depths and seasonal changes in the surface frozen layer. Maximum tidal strength over a few days, rather than hourly water level, may be more closely associated with the possibility of ebullition occurrence as it represents a trade-off time scale in between hourly and lunar periods.

  19. Spatial patterns of subtidal nematodes and macrofauna assemblages along the estuarine gradient to assess benthic condition: Definition of homogenous sectors along a naturally stressed estuary (Portugal).

    OpenAIRE

    Adao, Helena; Medeiros, João; Alves, Ana; Chainho, Paula; Costa, Lino; Costa, M. J.; Marques, J. C.

    2010-01-01

    In transitional waters the definition of reference conditions must take into account the natural variability. Therefore, prior to the use of environmental quality assessment tools the estuarine stretches reflecting different physical-chemical and biological conditions should be defined in order to correctly establish the benthic specific reference conditions. The main goal of this study is the definition of homogeneous sectors along a naturally stressed estuary by: analysis of the structu...

  20. Anaerobic ammonium oxidation in an estuarine sediment

    OpenAIRE

    Risgaard-Petersen, N.; Meyer, R.L.; Schmid, M.C.; Jetten, M.S.M.; Enrich-Prast, A.; Rysgaard, S.; Revsbech, N.P.

    2004-01-01

    The occurrence and significance of the anammox (anaerobic ammonium oxidation) process relative to denitrification was studied in photosynthetically active sediment from 2 shallow-water estuaries: Randers Fjord and Norsminde Fjord, Denmark. Anammox accounted for 5 to 24 % of N-2 production in Randers Fjord sediment, whereas no indication was seen of the process in sediment from Norsminde Fjord, It is suggested that the presence of anammox in Randers Fjord and its absence from Norsminde Fjord i...

  1. Current status of intestinal parasitic infections among inhabitants of the Ghazni and Parwan provinces, Afghanistan

    Directory of Open Access Journals (Sweden)

    Krzysztof Korzeniewski

    2017-03-01

    Full Text Available Background. The prevalence rates of food- and waterborne parasitic infections in Afghanistan are unknown. Cases of invasive diseases found in Afghans are rarely laboratory-confirmed. Objectives . The aim of the study was to present the current status of intestinal parasitic infections in Afghan inhabitants on the example of patients hospitalized in two healthcare facilities in eastern Afghanistan. Material and methods . Fecal samples were collected from 548 patients (children aged 1–17 years and adults with internal complaints, treated in Ghazni Provincial Hospital (Afghan civilian medical center, Ghazni province, 180 south-west of Kabul and in Bagram Korean Hospital (Korean military medical center for Afghan patients, Parwan province, 60 km north of Kabul between 2013 and 2014. One to three stool specimens from Afghan patients were fixed in 10% formalin, transported to the Military Institute of Medicine in Poland and tested by light microscopy using three diagnostic methods (direct smear in Lugol’s solution, decantation in distilled water and Fülleborn’s flotation. Results . Intestinal parasites were found in 144/386 of tested patients from the Ghazni province (37.3% infected, mainly with Ascaris lumbricoides , Giardia intestinalis , Hymenolepis nana and in 49/162 patients from the Parwan province (30.2% infected, mainly with G. intestinalis , A. lumbricoides , H. nana . Conclusions . The rates of intestinal parasitic infections among Afghans are high. The wide range of the detected parasites (protozoa, nematodes, cestodes should result in the introduction of general screening to be conducted regularly among inhabitants of Afghanistan and the application of targeted antiparasitic chemotherapy aiming to eliminate intestinal helminths and protozoa from the local community.

  2. Lagrangian structure of flows in the Chesapeake Bay: challenges and perspectives on the analysis of estuarine flows

    Directory of Open Access Journals (Sweden)

    M. Branicki

    2010-03-01

    Full Text Available In this work we discuss applications of Lagrangian techniques to study transport properties of flows generated by shallow water models of estuarine flows. We focus on the flow in the Chesapeake Bay generated by Quoddy (see Lynch and Werner, 1991, a finite-element (shallow water model adopted to the bay by Gross et al. (2001. The main goal of this analysis is to outline the potential benefits of using Lagrangian tools for both understanding transport properties of such flows, and for validating the model output and identifying model deficiencies. We argue that the currently available 2-D Lagrangian tools, including the stable and unstable manifolds of hyperbolic trajectories and techniques exploiting 2-D finite-time Lyapunov exponent fields, are of limited use in the case of partially mixed estuarine flows. A further development and efficient implementation of three-dimensional Lagrangian techniques, as well as improvements in the shallow-water modelling of 3-D velocity fields, are required for reliable transport analysis in such flows. Some aspects of the 3-D trajectory structure in the Chesapeake Bay, based on the Quoddy output, are also discussed.

  3. Modelling the occurrence of postflexion stages of a marine estuarine-dependent fish in temperate South African estuaries

    Directory of Open Access Journals (Sweden)

    Yanasivan Kisten

    2017-03-01

    Full Text Available The movement of postflexion larvae of marine estuarine-dependent species into estuaries is critical for the survival of fishes reliant on estuaries as nurseries. However, detailed studies focused on environmental variability experienced by postflexion larvae entering a range of estuary types under varying conditions are rare. This study assessed the in situ conditions (temperature, salinity and water clarity under which the southern African endemic fish Rhabdosargus holubi (Sparidae recruits into estuaries. Postflexion larvae were sampled in three biogeographic regions (cool temperate, warm temperate and subtropical boundary, which included three estuary types (permanently open estuaries (POEs, temporarily open/closed estuaries and estuarine lake systems on a seasonal basis, independent of each other. Rhabdosargus holubi larvae were more abundant in spring and summer, in POEs in the warm temperate region. Models predicted that higher larval occurrence in estuaries is a function of lower salinity (e.g. mesohaline zones of 5-17.9 salinity and lower water clarity (e.g. 0-0.2 Kd, light extinction coefficient, particularly for warm, temperate POEs. This re-emphasizes the importance of freshwater for optimal nursery functioning, which may be compromised by impoundments, abstraction and climate change in water-short countries like South Africa.

  4. Effect of physical parameters on the in situ survival of Escherichia coli MC-6 in an estuarine environment.

    Science.gov (United States)

    Faust, M A; Aotaky, A E; Hargadon, M T

    1975-11-01

    Survival of Escherichia coli MC-6 of fecal origin in an estuarine environment as affected by time, water temperature, dissolved oxygen, salinity, and montmorillonite in diffusion chambers has been elucidated. Several in situ physical parameters were recorded simultaneously, and viable cell numbers were estimated. The survival of the bacteria varied seasonally. Montmorillonite addition extended the time needed for a 50% reduction of the viable cell population (t1/2) of cells by 40% over the t1/2 of cells in Rhode River water alone. The effect of this clay was not significantly greater between 50- to 1,000 mug/ml montmorillonite concentrations. In all experiments, the relationships among pairs of variables were studied by regression and correlation analysis. The slope between viable cell numbers and water temperatures increased about 50% for each 10 C increment in temperature and gave a correlation coefficient r = 0.617, significant at 95% confidence level. A similar correlation coefficient, r = 0.670, was obtained between water temperature and t1/2 of the initial cell population. In all experiments regressions were performed considering all variables after bacteria had been in the Rhode River environment for 3 days. Coefficient of multiple determination was estimated as R2 = 0.756. Approximately 75.6% of the variance of viable cell numbers can be explained by variation in water temperature, dissolved oxygen, and salinity. Simple correlation coefficients within the regression steps were also computed. Survival of bacteria was closely and negatively correlated with increasing water temperature (r = -0.717). It is suggested that water temperature is the most important factor in predicting fecal coliform survival from point and nonpoint sources in assessing water quality in an estuarine ecosystem.

  5. CHEMOSENSORY ATTRACTION OF ZOOSPORES OF THE ESTUARINE DINOFLAGELLATES, PFIESTERIA PISCICIDA AND P. SHUMWAYAE, TO FINFISH MUCUS AND EXCRETA. (R825551)

    Science.gov (United States)

    Toxic strains of the estuarine dinoflagellates, Pfiesteria piscicida and P. shumwayae, can cause fish death and disease, whereas other estuarine `lookalike' species such as cryptoperidiniopsoids have not been ichthyotoxic under ecologically rel...

  6. Assessment of the climate change impacts on fecal coliform contamination in a tidal estuarine system.

    Science.gov (United States)

    Liu, Wen-Cheng; Chan, Wen-Ting

    2015-12-01

    Climate change is one of the key factors affecting the future microbiological water quality in rivers and tidal estuaries. A coupled 3D hydrodynamic and fecal coliform transport model was developed and applied to the Danshuei River estuarine system for predicting the influences of climate change on microbiological water quality. The hydrodynamic and fecal coliform model was validated using observational salinity and fecal coliform distributions. According to the analyses of the statistical error, predictions of the salinity and the fecal coliform concentration from the model simulation quantitatively agreed with the observed data. The validated model was then applied to predict the fecal coliform contamination as a result of climate change, including the change of freshwater discharge and the sea level rise. We found that the reduction of freshwater discharge under climate change scenarios resulted in an increase in the fecal coliform concentration. The sea level rise would decrease fecal coliform distributions because both the water level and the water volume increased. A reduction in freshwater discharge has a negative impact on the fecal coliform concentration, whereas a rising sea level has a positive influence on the fecal coliform contamination. An appropriate strategy for the effective microbiological management in tidal estuaries is required to reveal the persistent trends of climate in the future.

  7. Phytoplankton productivity and biomass in the Charlotte Harbor estuarine system, Florida

    Science.gov (United States)

    McPherson, Benjamin F.; Montgomery, Ralph T.; Emmons, Edward E.

    1990-01-01

    Phytoplankton carbon-14 productivity at a depth of 50 percent of surface light and chlorophyll-a concentrations were measured every other month from November 1985 through September 1986 at 12 stations in the Charlotte Harbor estuarine system. Maximum productivity and chlorophyll-a concentrations occurred during summer or early autumn near the months of tidal rivers. Most of the variability in light-normalized productivity and chlorophyll-a could be attributed to two factors derived from Principal Component Analysis of ambient water-quality characteristics. One factor related to seasonal variability and the other to spatial variability. The seasonal factor incorporated the interaction of temperature and nutrients. The spatial factor incorporated the interaction of salinity, nutrients, and water color that resulted from the mixing of freshwater inflow and seawater. Although freshwater inflow increased the availability of nutrients in low salinity (less than 10 %) waters, the highly colored freshwater restricted light penetration and phytoplankton productivity. Maximum productivity and biomass occurred where color associated with the freshwater inflow had been diluted by seawater so that light and nutrients were both available. Concentrations of inorganic nitrogen were often at or below detection limit throughout most of the high salinity (greater than 20 %) waters of the estuary and was probably the most critical nutrient in limiting phytoplankton productivity.

  8. Linking groundwater discharge to severe estuarine acidification during a flood in a modified wetland.

    Science.gov (United States)

    de Weys, Jason; Santos, Isaac R; Eyre, Bradley D

    2011-04-15

    Periodic acidification of waterways adjacent to coastal acid sulfate soils (CASS) is a significant land and water management issue in the subtropics. In this study, we use 5-months of continuous radon ((222)Rn, a natural groundwater tracer) observations to link estuarine acidification to groundwater discharge in an Australian CASS catchment (Tuckean Swamp). The radon time series began in the dry season, when radon activities were low (2-3 dpm L(-1)), and the pH of surface water was 6.4. We captured a major rain event (213 mm on 2 March 2010) that flooded the catchment. An immediate drop in pH during the flood may be attributed to surface water interactions with soil products. During the post-flood stage, increased radon activities (up to 19.3 dpm L(-1)) and floodplain groundwater discharge rates (up to 2.01 m(3) s(-1), equivalent to 19% of total runoff) coincided with low pH (3.77). Another spike in radon activities (13.2 dpm L(-1)) coincided with the lowest recorded surface water pH (3.62) after 72 mm of rain between 17 and 20 April 2010. About 80% of catchment acid exports occurred when the estuary was dominated by groundwater discharging from highly permeable CASS during the flood recession.

  9. Observations of Lower Mississippi River Estuarine Dynamics: Effects of the Salt Wedge on Sediment Deposition

    Science.gov (United States)

    Ramirez, M. T.; Allison, M. A.

    2017-12-01

    The lowermost Mississippi River is subject to salt-wedge estuarine conditions during seasonally low flow, when seaward flow is unable to overcome density stratification. Previous studies in the Mississippi River salt wedge have shown the deposition of a fine sediment layer accumulating several mm/day beneath the reach where the salt wedge is present. Field studies were conducted during low flow in 2012-2015 utilizing ADCP, CTD, LISST, and physical samples to observe the physics of the salt wedge reach and to calculate rates and character of sediment trapping beneath the salt wedge. The field observations were summarized using a two-layer box-model representation of the reach to calculate water and sediment budgets entering, exiting, and stored within the reach. The salt wedge reach was found to be net depositional at rates up to 1.8 mm/day. The mechanism for transferring sediment mass from the downstream-flowing fluvial layer to the upstream-flowing marine layer appears to be flocculation, evidenced in LISST data by a spike in sediment particle diameters at the halocline. Applying reach-averaged rates of sediment trapping to a time-integrated model of salt-wedge position, we calculated annual totals ranging from 0.025 to 2.2 million tons of sediment deposited beneath the salt wedge, depending on salt-wedge persistence and upstream extent. Most years this seasonal deposit is remobilized during spring flood following the low-flow estuarine season, which may affect the timing of sediment delivery to the Gulf of Mexico, as well as particulate organic carbon, whose transport trajectory mirrors that of mineral sediment. These results are also relevant to ongoing dredging efforts necessary to maintain the economically-important navigation pathway through the lower Mississippi River, as well as planned efforts to use Mississippi River sedimentary resources to build land in the degrading Louisiana deltaic coast.

  10. Estuarine fish health assessment: Evidence of wastewater impacts based on nitrogen isotopes and histopathology

    Energy Technology Data Exchange (ETDEWEB)

    Schlacher, Thomas A. [Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore DC, QLD 4558 (Australia)], E-mail: tschlach@usc.edu.au; Mondon, Julie A. [School of Life and Environmental Sciences, Deakin University, Warrnambool (Australia)], E-mail: julie.mondon@deakin.edu.au; Connolly, Rod M. [Australian Rivers Institute - Coast and Estuaries and Griffith School of Environment, Griffith University (Australia)], E-mail: r.connolly@griffith.edu.au

    2007-11-15

    Sewage effluent is a powerful agent of ecological change in estuaries. While the effects of sewage pollution on water quality are usually well documented, biological responses of exposed organisms are not. We quantified health impacts in the form of pathological tissue changes across multiple organs in estuarine fish exposed to elevated levels of treated wastewater. Structural pathologies were compared in wild populations of four fish species from two subtropical estuaries on the east coast of Australia that differ substantially in the amount of direct wastewater loadings. Uptake of sewage-derived nitrogen by fish was traced with stable nitrogen isotopes. Pathologies were common in the liver, spleen, gill, kidney and muscle tissues, and included granulomas, melanomacrophage aggregates, and multiple deformities of the gill epithelia. Tissue deformities were more frequent in fish exposed directly to wastewater discharges. Mullet (Valamugil georgii) were most affected, with only a single specimen free of pathologies in the sewage-impacted estuary. Similarly, in those fish that had structural abnormalities, more deformities were generally found in individuals from sites receiving sewage. These spatial contrasts in impaired fish health correspond to significantly enriched {delta}{sup 15}N values in fish muscle as a consequence of fish assimilating sewage-N. Overall, the pattern of lower health and enriched {delta}{sup 15}N values in fish from sewage-impacted areas suggests that organism health is lowered by sewage inputs to estuaries. Measurements of organism health are required to understand the effects of sewage on estuarine ecosystems, and histopathology of fishes is a powerful tool to achieve this.

  11. Temporal changes of accretion rates on an estuarine salt marsh during the late Holocene

    DEFF Research Database (Denmark)

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

    2007-01-01

    The temporal variability of estuarine sedimentation has been investigated in the northernmost part of theWadden Sea (Denmark), using an estuarine sedimentary sequence at Ho Havn. The sedimentary sequence appears to have been deposited within the last ~2000 yr based on detailed luminescence dating...

  12. The predation impact of juvenile herring Clupea harengus and sprat Sprattus sprattus on estuarine zooplankton

    NARCIS (Netherlands)

    Maes, J.; Tackx, M.; Soetaert, K.E.R.

    2005-01-01

    The consumption of estuarine copepods by juvenile herring and sprat during estuarine residency was estimated using fish biomass data and daily rations calculated from two models of feeding in fish: a bioenergetic model and a gastric evacuation model. The bioenergetic model predicted daily rations

  13. Macrobenthic species response surfaces along estuarine gradients: prediction by logistic regression

    NARCIS (Netherlands)

    Ysebaert, T.; Meire, P.; Herman, P.M.J.; Verbeek, H.

    2002-01-01

    This study aims at contributing to the development of statistical models to predict macrobenthic species response to environmental conditions in estuarine ecosystems. Ecological response surfaces are derived for 10 estuarine macrobenthic species. Logistic regression is applied on a large data set,

  14. Earthquake impacts on microcrustacean communities inhabiting groundwater-fed springs alter species-abundance distribution patterns.

    Science.gov (United States)

    Fattorini, Simone; Di Lorenzo, Tiziana; Galassi, Diana M P

    2018-01-24

    Earthquakes are important natural events, yet their impacts on animal communities are poorly known. Understanding earthquake impacts on groundwater communities is essential to assess their resilience and hence to perform conservation actions. We investigated how a 6.3 M w earthquake that occurred in 2009 altered the community structure (diversity, evenness, dominance, species abundance distributions and beta-diversity) of microcrustaceans (Crustacea Copepoda) inhabiting springs fed by the Gran Sasso Aquifer (Central Italy). Sampling was done in low-discharge (1997), high-discharge (2005), and post-seismic (2012) hydrological years. Stygobites (obligate groundwater species) and non-stygobites (non-obligate groundwater species) showed different patterns. A high-water discharge in 2005 altered abundance patterns of non-stygobites. The earthquake re-established former abundance patterns. Stygobites were less affected by high-water discharge in 2005, and showed strong increases in diversity and evenness after the earthquake. This effect was due to the fact that the earthquake induced a strong population decline of previously dominant stygobites (especially of Nitocrella pescei) in the aquifer, and subsequently at the main spring outlets, thus allowing a more equitable species-abundance distribution. These results highlight the importance of considering species ecology to understand the effects of a significant earthquake event on animal communities.

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

    Science.gov (United States)

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

    2014-01-01

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

  16. Impact of boat-generated waves on intertidal estuarine sediments

    Science.gov (United States)

    Blanpain, O.; Deloffre, J.; Lafite, R.; Gomit, G.; Calluaud, D.; David, L.

    2010-12-01

    Hydrodynamics in the macrotidal Seine estuary (France) are controlled by the semi-diurnal tidal regime modulated seasonally by the fluvial discharge. Wind effect on sediment transport (through wind waves and swell) is observed at the mouth of the estuary. Over the last century, authorities have put emphasis on facilitating economic exchanges by means of embankment building and increased dredging activity. These developments led to allow and secure sea vessel traffic in the Seine estuary (from its mouth to the port of Rouen, 125 km upstream) but they also resulted in a change of estuarine hydrodynamics and sediment transport features. A riversides restoration policy has been recently started by port authorities. In this context, the objective of the field-based study presented is to connect vessel characteristics (i.e. speed, draft...), boat-generated waves and their sedimentary impacts. Such information will be used by stakeholders to manage riverside. The natural intertidal site of interest is located in the fluvial freshwater part of the Seine estuary characterized by a 4.5 m maximum tidal range. The foreshore slope is gently decreasing and surface sediments are composed of fine to coarse sand with occasional mud drapes. In order to decipher boat-generated events, the sampling strategy is based on continuous ADV measurements coupled with a turbidimeter and an altimeter to study sediment dynamics. These instruments are settled in the lower part of the foreshore (i) to obtain a significant dataset (i.e. oceanic instruments are not measuring in air) on a zone statically affected by boat waves and (ii) because most of boat traffic occurs during early flood or late ebb period. Spatial variations are assessed along a cross-section through grain-size analysis of surface sediments and topography measurements using pole technique. Results enhance hydrodynamic and sedimentary impacts of boat-generated waves compared respectively to tidal and wind effects. Long

  17. The use of the osteoderms of estuarine crocodiles as archives of their environmental exposure to elemental contaminants

    International Nuclear Information System (INIS)

    Jeffree, R.; Markich, S.; Twining, J.; Prince, K.; Hammerton, K.; Jayasinghe, N.

    2000-01-01

    Full text: Previous studies on Pb concentrations in the osteoderms of estuarine crocodiles from Kakadu National Park have demonstrated enhanced levels in populations known to consume fauna shot with lead ammunition by the traditional owners. SEM studies confirmed the laminated structure of osteoderms and SIMS analyses of Pb:Ca ratios across these laminations showed consistently high values for crocodiles from Pb-exposed habitats. These results pointed to their continual exposure during most of their lifetime. There were several assumptions implicit in this conclusion: a) Pb is retained and solubilised in the stomach and then absorbed into the blood, b)The osteodermal lamination under construction during Pb absorption will contains an elevated Pb concentration. Osteoderms from exposed crocodiles are currently being analysed by SIMS to test assumption. Osteodermal cores have also been taken from the mounted skin of Sweetheart in the NT Museum and Art Gallery for SIMS analysis. This crocodile inhabited the Finniss River before and during mining activities at Rum Jungle between the 1950's to 1970's. Analyses of the osteodermal laminations will determine if pollution loads of Cu, Zn, Mn and U were archived. Analysis of total osteoderms for element content have shown that concentrations of Mg are significantly (P<0.05) and linearly related to crocodile size and inferred age. SIMS analysis of Mg in individual laminations will be undertaken to determine whether this relationship is linear or exponential

  18. From occupying to inhabiting - a change in conceptualising comfort

    International Nuclear Information System (INIS)

    Jaffari, Svenja D; Matthews, Ben

    2009-01-01

    ; secondly, that it promotes technologies that treat environmental parameters as variables for our manipulation, rather than opportunities to reflect on, and adjust our own (temporal human) fit with our environment. Borrowing from Cole et al. [4], we argue for technologies that enable users to inhabit rather than occupy the built environment.

  19. Tidal variations in the Sundarbans estuarine system, India

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterjee, M.; Shankar, D.; Sen, G.K.; Sanyal, P.; Sundar, D.; Michael, G.S.; Chatterjee, A.; Amol, P.; Mukherjee, D.; Suprit, K.; Mukherjee, A.; Vijith, V.; Chatterjee, S.; Basu, A.; Das, M.; Chakraborti, S.; Kalla, A.; Misra, S.K.; Mukhopadhyay, S.; Mandal, G.; Sarkar, K.

    ). The map was prepared by digitizing the 1967–1969 toposheets (1:50,000 scale) of the Survey of India. The symbols (an ‘S’ with arrows on either end) indicating the presence of the tide were filled in from these toposheets and the more recent map (1... the Gomdi Khaal or the Gomor), Gos- aba, Gona, Harinbhanga and Raimangal (figure 2). Interconnecting these estuaries and forming the complex estuarine network are numerous west–east flowing channels, canals and creeks. Some of these interlinking channels...

  20. A checklist of malacofauna of the Vellar Estuarine Mangroves, India

    Directory of Open Access Journals (Sweden)

    K. Kesavan

    2009-07-01

    Full Text Available A survey conducted to know the diversity of malacofauna in Vellar estuarine mangroves (southeast coast of India. In this study, 13 species of molluscs (10 species of gastropods - Melampus ceylonicus, Cerithidea cingulata, Cassidula nucleus, Pythia plicata, Neritina (Dostia violacea, Littorina scabra, Littorina melanostoma, Ellobium aurisjudae, C. obtusa T. telescopium and Assiminea nitida and 3 species of bivalves - Perna viridis, Crassostrea madrasensis and Modiolus metcalfei were recorded. M. pulchella, C. obtusa, L. scabra and N. violacea were found arboreal. T. telescopium, C. cingulata and E. aurisjudae were found crawling on the intertidal mud.

  1. Zooplankton variability in the subtropical estuarine system of Paranaguá Bay, Brazil, in 2012 and 2013

    Science.gov (United States)

    Salvador, Bianca; Bersano, José Guilherme F.

    2017-12-01

    Spatial and temporal dynamics of zooplankton assemblages were studied in the Paranaguá Estuarine System (southern Brazil), including data from the summer (rainy) and winter (dry) periods of 2012 and 2013. Zooplankton and environmental data were collected at 37 stations along the estuary and examined by multivariate methods. The results indicated significantly distinct assemblages; differences in abundance were the major source of variability, mainly over the temporal scale. The highest abundances were observed during rainy periods, especially in 2012, when the mean density reached 16378 ind.m-3. Winter assemblages showed lower densities but higher species diversity, due to the more extensive intrusion of coastal waters. Of the 14 taxonomic groups recorded, Copepoda was the most abundant and diverse (92% of total abundance and 22 species identified). The coastal copepods Acartia lilljeborgi (44%) and Oithona hebes (26%) were the most important species in both abundance and frequency, followed by the estuarine Pseudodiaptomus acutus and the neritic Temora turbinata. The results indicated strong influences of environmental parameters on the community structure, especially in response to seasonal variations. The spatial distribution of species was probably determined mainly by their preferences and tolerances for specific salinity conditions. On the other hand, the abundances were strongly related to higher water temperature and precipitation rates, which can drive nutrient inputs and consequently food supply in the system, due to intense continental drainage.

  2. Drivers of change in estuarine-coastal ecosystems: Discoveries from four decades of study in San Francisco Bay

    Science.gov (United States)

    Cloern, J.E.; Jassby, A.D.

    2012-01-01

    Poised at the interface of rivers, ocean, atmosphere and dense human settlement, estuaries are driven by a large array of natural and anthropogenic forces. San Francisco Bay exemplifies the fast-paced change occurring in many of the world's estuaries, bays and inland seas in response to these diverse forces. We use observations from this particularly well-studied estuary to illustrate responses to six drivers that are common agents of change where land and sea meet: water consumption and diversion; human modification of sediment supply; introduction of non-native species; sewage input; environmental policy; and climate shifts. In San Francisco Bay, responses to these drivers include, respectively, shifts in the timing and extent of freshwater inflow and salinity intrusion; decreasing turbidity; restructuring of plankton communities; nutrient enrichment; elimination of hypoxia and reduced metal contamination of biota; and food web changes that decrease resistance of the estuary to nutrient pollution. Detection of these changes and discovery of their causes through environmental monitoring have been essential for establishing and measuring outcomes of environmental policies that aim to maintain high water quality and sustain services provided by estuarine-coastal ecosystems. The wide range of variability time scales and the multiplicity of interacting drivers place heavy demands on estuarine monitoring programs. But the San Francisco Bay case study illustrates why the imperative for monitoring has never been greater.

  3. Uranium-series radionuclides as tracers of geochemical processes in Long Island Sound. [Natural /sup 210/Pb tracer study of estuarine geochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Benninger, L.K.

    1976-05-01

    An estuary can be visualized as a membrane between land and the deep ocean, and the understanding of the estuarine processes which determine the permeability of this membrane to terrigenous materials is necessary for the estimation of fluxes of these materials to the oceans. Natural radionuclides are useful probes into estuarine geochemistry because of the time-dependent relationships among them and because, as analogs of stable elements, they are much less subject to contamination during sampling and analysis. In this study the flux of heavy metals through Long Island Sound is considered in light of the material balance for excess /sup 210/Pb, and analyses of concurrent seston and water samples from central Long Island Sound are used to probe the internal workings of the estuary.

  4. Why large cells dominate estuarine phytoplankton

    Science.gov (United States)

    Cloern, James E.

    2018-01-01

    Surveys across the world oceans have shown that phytoplankton biomass and production are dominated by small cells (picoplankton) where nutrient concentrations are low, but large cells (microplankton) dominate when nutrient-rich deep water is mixed to the surface. I analyzed phytoplankton size structure in samples collected over 25 yr in San Francisco Bay, a nutrient-rich estuary. Biomass was dominated by large cells because their biomass selectively grew during blooms. Large-cell dominance appears to be a characteristic of ecosystems at the land–sea interface, and these places may therefore function as analogs to oceanic upwelling systems. Simulations with a size-structured NPZ model showed that runs of positive net growth rate persisted long enough for biomass of large, but not small, cells to accumulate. Model experiments showed that small cells would dominate in the absence of grazing, at lower nutrient concentrations, and at elevated (+5°C) temperatures. Underlying these results are two fundamental scaling laws: (1) large cells are grazed more slowly than small cells, and (2) grazing rate increases with temperature faster than growth rate. The model experiments suggest testable hypotheses about phytoplankton size structure at the land–sea interface: (1) anthropogenic nutrient enrichment increases cell size; (2) this response varies with temperature and only occurs at mid-high latitudes; (3) large-cell blooms can only develop when temperature is below a critical value, around 15°C; (4) cell size diminishes along temperature gradients from high to low latitudes; and (5) large-cell blooms will diminish or disappear where planetary warming increases temperature beyond their critical threshold.

  5. Water footprints of nations

    NARCIS (Netherlands)

    Chapagain, Ashok; Hoekstra, Arjen Ysbert

    The water footprint concept has been developed in order to have an indicator of water use in relation to consumption of people. The water footprint of a country is defined as the volume of water needed for the production of the goods and services consumed by the inhabitants of the country. Closely

  6. Water

    Science.gov (United States)

    ... www.girlshealth.gov/ Home Nutrition Nutrition basics Water Water Did you know that water makes up more ... to drink more water Other drinks How much water do you need? top Water is very important, ...

  7. The Effects of Varying Salinity on Ammonium Exchange in Estuarine Sediments of the Parker River, Massachusetts

    DEFF Research Database (Denmark)

    Weston, Nathaniel B.; Giblin, Anne E; Banta, Gary Thomas

    2010-01-01

    We examined the effects of seasonal salinity changes on sediment ammonium (NH4+) adsorption and exchange across the sediment–water interface in the Parker River Estuary, by means of seasonal field sampling, laboratory adsorption experiments, and modeling. The fraction of dissolvedNH4+relative to ...... be of similar magnitude to rates of organic nitrogen mineralization and may therefore be important in supporting estuarine productivity when watershed inputs of N are low.......We examined the effects of seasonal salinity changes on sediment ammonium (NH4+) adsorption and exchange across the sediment–water interface in the Parker River Estuary, by means of seasonal field sampling, laboratory adsorption experiments, and modeling. The fraction of dissolvedNH4+relative...... to adsorbedNH4+in oligohaline sediments rose significantly with increased pore water salinity over the season. Laboratory experiments demonstrated that small (∼3) increases in salinity from freshwater conditions had the greatest effect onNH4+adsorption by reducing the exchangeable pool from 69% to 14...

  8. Metal Bioaccumulation by Estuarine Food Webs in New England, USA

    Directory of Open Access Journals (Sweden)

    Celia Y. Chen

    2016-06-01

    Full Text Available Evaluating the degree of metal exposure and bioaccumulation in estuarine organisms is important for understanding the fate of metals in estuarine food webs. We investigated the bioaccumulation of Hg, methylmercury (MeHg, Cd, Se, Pb, and As in common intertidal organisms across a watershed urbanization gradient of coastal marsh sites in New England to relate metal exposure and bioaccumulation in fauna to both chemical and ecological factors. In sediments, we measured metal and metalloid concentrations, total organic carbon (TOC and SEM-AVS (Simultaneously extracted metal-acid volatile sulfides. In five different functional feeding groups of biota, we measured metal concentrations and delta 15N and delta 13C signatures. Concentrations of Hg and Se in biota for all sites were always greater than sediment concentrations whereas Pb in biota was always lower. There were positive relationships between biota Hg concentrations and sediment concentrations, and between biota MeHg concentrations and both pelagic feeding mode and trophic level. Bioavailability of all metals measured as SEM-AVS or Benthic-Sediment Accumulation Factor was lower in more contaminated sites, likely due to biogeochemical factors related to higher levels of sulfides and organic carbon in the sediments. Our study demonstrates that for most metals and metalloids, bioaccumulation is metal specific and not directly related to sediment concentrations or measures of bioavailability such as AVS-SEM.

  9. The effects of temperature on oxygen uptake and nutrient flux in sediment inhabited by molluscs

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2013-02-01

    Full Text Available Benthic invertebrates play important roles in oxygen uptake and nutrient cycling in the benthic boundary layer. Temperature is an important factor that influences both invertebrate activity and the effects of the bioturbation on biogeochemistry. The present study aimed to investigate the influence of temperature on the sediment oxygen uptake and nutrient flux across the sediment-water interface in sediment inhabited by molluscs, animals that often dominate the benthic community. A microcosm was constructed using sediment, lake water, and molluscs from Lake Taihu, China. The clam Corbicula fluminea (Bivalvia: Corbiculidae and the snail Bellamya aeruginosa (Gastropoda: Viviparidae were selected for the experiment because they dominate the benthic community in the lake. The effect of C. fluminea and B. aeruginosa on sediment oxygen uptake and nutrient flux was simultaneously examined at both 15 and 25℃. The results indicated that C. fluminea significantly increased the sediment oxygen uptake and release of soluble reactive phosphorus (SRP and ammonium from the sediment to the overlying water at both temperatures, and the net sediment oxygen uptake, and the net SRP and ammonium fluxes caused by the clams were significantly higher at 25℃ than at 15℃. Moreover, B. aeruginosa significantly increased the sediment oxygen uptake at the two experimental temperatures, however the net sediment oxygen uptake induced by the snail did not differ significantly between 15 and 25℃. The SRP released from the sediment was stimulated significantly by B. aeruginosa at 25℃, and B. aeruginosa also produced significantly more net SRP release at 25℃ than that at 15℃. In contrast, the influence of B. aeruginosa on the net ammonium flux at each temperature was not statistically significant.

  10. Assessing dissolved carbon transport and transformation along an estuarine river with stable isotope analyses

    Science.gov (United States)

    He, Songjie; Xu, Y. Jun

    2017-10-01

    Estuaries play an important role in the dynamics of dissolved carbon from rivers to coastal oceans. However, our knowledge of dissolved carbon transport and transformation in mixing zones of the world's coastal rivers is still limited. This study aims to determine how dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC) concentrations and stable isotopes (δ13CDIC and δ13CDOC) change along an 88-km long estuarine river, the Calcasieu River in Louisiana, southern USA, with salinity ranging from 0.02 to 21.92. The study is expected to elucidate which processes most likely control carbon dynamics in a freshwater-saltwater mixing system, and to evaluate the net metabolism of this estuary. Between May 2015 and February 2016, water samples were collected and in-situ measurements on ambient water conditions were performed during five field trips at six sites from upstream to downstream of the Calcasieu River, which enters the Northern Gulf of Mexico (NGOM). The DIC concentration and δ13CDIC increased rapidly with increasing salinity in the mixing zone. The average DIC concentration and δ13CDIC at the site closest to the NGOM (site 6) were 1.31 mM and -6.34‰, respectively, much higher than those at the site furthest upstream (site 1, 0.42 mM and -20.83‰). The DIC concentrations appeared to be largely influenced by conservative mixing, while high water temperature may have played a role in deviating DIC concentration from the conservative line due likely to increased respiration and decomposition. The δ13CDIC values were close to those suggested by the conservative mixing model for May, June and November, but lower than those for July and February, suggesting that an estuarine river can fluctuate from a balanced to a heterotrophic system (i.e., production/respiration (P/R) < 1) seasonally. Unlike the DIC longitudinal trend, the DOC concentrations in the river estuary decreased from upstream to downstream, but to a much smaller degree. The DOC

  11. Cytogenetic findings from inhabitants of different ages in high background radiation areas of Yangjiang

    International Nuclear Information System (INIS)

    Chen Deqing; Yao Suyan; Zhang Chaoyang

    1997-01-01

    Objective: To explore the relationship between high background radiation and injurious effect on inhabitants. Method: Peripheral blood samples were collected from the inhabitants of 10, 40, 55 and 70 years old in high background radiation areas (HBRA) of Yangjiang, Chromosome preparations were carried out with conventional whole-blood microculture. Results: The percentage of dicentric chromosome with fragments in inhabitants of HBRA was significantly higher than that in control areas (CA) (0.469% vs. 0.315%, P<0.01), and there was an increase in the aberration frequencies with age (or accumulated doses). Conclusion: Chromosome aberration is an extremely sensitive indicator of radiation damage and a good radio-biodosimeter

  12. The safety of Ignalina NPP and ecological danger in public opinion of inhabitants of Daugavpils region

    International Nuclear Information System (INIS)

    Peipinia, O.

    1998-01-01

    Inquest of Daugavpils' region pointed to a big anxiety for ecological danger of Ignalina NPP by inhabitants and experts. Absolute majority of respondents (73-78% inhabitants and 68-82% experts) apprehend the NPP as very dangerous and dangerous. More than half of respondents apprehend the dangerous increased during last two-three years. It is because no one has a good reference about situation, because tragic al Chernobyl NPP burst was on. The anxiety increases if the respondent lives nearer of NPP. Inhabitants of Daugavpils and it's region wants the better reference about situation, about future of Ignalina NPP after 2010 year, about securities means in case of NPP burst. (author)

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

    International Nuclear Information System (INIS)

    Naqvi, S.R.; Inam, Z.

    2005-01-01

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

  14. High Genetic Diversity and Novelty in Eukaryotic Plankton Assemblages Inhabiting Saline Lakes in the Qaidam Basin

    Science.gov (United States)

    Wang, Jiali; Wang, Fang; Chu, Limin; Wang, Hao; Zhong, Zhiping; Liu, Zhipei; Gao, Jianyong; Duan, Hairong

    2014-01-01

    Saline lakes are intriguing ecosystems harboring extremely productive microbial communities in spite of their extreme environmental conditions. We performed a comprehensive analysis of the genetic diversity (18S rRNA gene) of the planktonic microbial eukaryotes (nano- and picoeukaryotes) in six different inland saline lakes located in the Qaidam Basin. The novelty level are high, with about 11.23% of the whole dataset showing Basin are also dominated by Holozoa group, accounting for 26.65% of the total number of sequence reads. Notably, Chlorophyta group are only found in high abundance in Lake Gasikule (28.00%), whereas less represented in other hypersaline lakes such as Gahai (0.50%) and Xiaochaidan (1.15%). Further analysis show that the compositions of planktonic eukaryotic assemblages are also most variable between different sampling sites in the same lake. Out of the parameters, four show significant correlation to this CCA: altitude, calcium, sodium and potassium concentrations. Overall, this study shows important gaps in the current knowledge about planktonic microbial eukaryotes inhabiting Qaidam Basin (hyper) saline water bodies. The identified diversity and novelty patterns among eukaryotic plankton assemblages in saline lake are of great importance for understanding and interpreting their ecology and evolution. PMID:25401703

  15. Benthic assemblages of a temperate estuarine system in South America: Transition from a freshwater to an estuarine zone

    Science.gov (United States)

    Cortelezzi, Agustina; Capítulo, Alberto Rodrigues; Boccardi, Lucía; Arocena, Rafael

    2007-12-01

    The objectives of the present study were to describe the species composition, diversity and distribution of the zoobenthic assemblages, to estimate the abundance and biomass of the dominant species, and to identify the main environmental factors determining the distribution patterns of the invertebrates from a freshwater to an estuarine zone in a temperate estuary of South America. The Río de la Plata estuary is a microtidal system characterized by a high concentration of suspended solids. Fifty-three taxa of meso- and macro-invertebrates were identified in the samples collected during November and December 2001. Molluscs, annelids, crustaceans and nematodes were found at 90% of the sampling sites. Molluscs comprised up to about 90% of the total zoobenthos biomass: the remaining percentage corresponded mainly to annelids and less to nematodes and crustaceans. An ecocline along the salinity gradient could be observed for the benthic assemblages from the freshwater to the estuarine zone in Rio de la Plata. A Canonical Correspondence Analysis shows that results from sampling sites in the outer zone were strongly related to salinity, depth and pH and less to oxygen and percentage of clay. The results from stations in the inner zone, and part of the middle zone, were mainly related to the occurrence of sand and contents of NH 4+-N, NO 3--N, and PO 43--P.

  16. Risk perceptions and preparedness of typhoon disaster on coastal inhabitants in China.

    Science.gov (United States)

    Jiang, Li-Ping; Yao, Lan; Bond, Eleanor F; Wang, Yu-Ling; Huang, Li-Quan

    2011-01-01

    China is highly vulnerable to natural disasters. Southeastern China situated on the Pacific Ocean experiences severe and devastating typhoons and hydrogeological disasters every year. Although respondents are highly aware of the typhoon outbreaks, they do not have necessary precautionary actions. This retrospective study evaluates the inhabitants' sociodemographic characteristics with risk perceptions and preparedness. Subjects (434 adults) were recruited from two rural areas in coastal south-eastern China, both with high typhoon exposure. One area (landfall area [LA]) was more severely affected than the other (surrounding area [SA) by the 2006 typhoon "Saomai." Subjects were interviewed using a structured questionnaire with items addressing sociodemographic characteristics and exposure to public education related to emergency preparedness, risk perception, and coping strategies. Overall, most residents (92 percent) were aware that they lived in a high-risk area. About 54.6 percent respondents chose media as the first approach to obtain preparedness education, and 32.4 percent of respondents thought that personal experience is an important tool to defend themselves from typhoon. In LA, residents perceived themselves to be at higher risk than those who lived in the SA. More than 66.5 percent of respondents were terrified by typhoon, and 62.2 percent of respondents were afraid of its recurrence. Respondents emphasized that their life style (61.4 percent), property losses (54.5 percent), and threat to life (52.4 percent) were influenced by typhoon attack. Coping behavior most likely to be adopted was "anticipatory food, water storage and residents in LA is significantly higher than SA (p dread associated with the risk axes (p > 0.05). However, in rescue and recovery of typhoon items, the score of familiarity with risk and dread with the risk axes is below 2.5. Regression analyses indicated that poor coping behavior was positively associated with age, risk perception

  17. Fishers' knowledge as a source of information about the estuarine dolphin (Sotalia guianensis, van Bénéden, 1864).

    Science.gov (United States)

    Manzan, Maíra Fontes; Lopes, Priscila F M

    2015-01-01

    Fishers' local ecological knowledge (LEK) is an additional tool to obtain information about cetaceans, regarding their local particularities, fishing interactions, and behavior. However, this knowledge could vary in depth of detail according to the level of interaction that fishers have with a specific species. This study investigated differences in small-scale fishers' LEK regarding the estuarine dolphin (Sotalia guianensis) in three Brazilian northeast coastal communities where fishing is practiced in estuarine lagoons and/or coastal waters and where dolphin-watching tourism varies from incipient to important. The fishers (N = 116) were asked about general characteristics of S. guianensis and their interactions with this dolphin during fishing activities. Compared to lagoon fishers, coastal fishers showed greater knowledge about the species but had more negative interactions with the dolphin during fishing activities. Coastal fishing not only offered the opportunity for fishers to observe a wider variety of the dolphin's behavior, but also implied direct contact with the dolphins, as they are bycaught in coastal gillnets. Besides complementing information that could be used for the management of cetaceans, this study shows that the type of environment most used by fishers also affects the accuracy of the information they provide. When designing studies to gather information on species and/or populations with the support of fishers, special consideration should be given to local particularities such as gear and habitats used within the fishing community.

  18. Drivers of Barotropic and Baroclinic Exchange through an Estuarine Navigation Channel in the Mississippi River Delta Plain

    Directory of Open Access Journals (Sweden)

    Gregg A. Snedden

    2016-04-01

    Full Text Available Estuarine navigation channels have long been recognized as conduits for saltwater intrusion into coastal wetlands. Salt flux decomposition and time series measurements of velocity and salinity were used to examine salt flux components and drivers of baroclinic and barotropic exchange in the Houma Navigation Channel, an estuarine channel located in the Mississippi River delta plain that receives substantial freshwater inputs from the Mississippi-Atchafalaya River system at its inland extent. Two modes of vertical current structure were identified from the time series data. The first mode, accounting for 90% of the total flow field variability, strongly resembled a barotropic current structure and was coherent with alongshelf wind stress over the coastal Gulf of Mexico. The second mode was indicative of gravitational circulation and was linked to variability in tidal stirring and the horizontal salinity gradient along the channel’s length. Tidal oscillatory salt flux was more important than gravitational circulation in transporting salt upestuary, except over equatorial phases of the fortnightly tidal cycle during times when river inflows were minimal. During all tidal cycles sampled, the advective flux, driven by a combination of freshwater discharge and wind-driven changes in storage, was the dominant transport term, and net flux of salt was always out of the estuary. These findings indicate that although human-made channels can effectively facilitate inland intrusion of saline water, this intrusion can be minimized or even reversed when they are subject to significant freshwater inputs.

  19. Finding refuge: The estuarine distribution of the nemertean egg predator Carcinonemertes errans on the Dungeness crab, Cancer magister

    Science.gov (United States)

    Dunn, Paul H.; Young, Craig M.

    2013-12-01

    Parasites can significantly impact ecosystems by altering the distributions and population sizes of their host organisms. Some hosts are thought to find refuge from parasitism by entering habitats where their parasites cannot survive. The nemertean worm Carcinonemertes errans is an egg predator that infects the Dungeness crab, Cancer magister, throughout the host's range. To determine if C. magister experiences a refuge from C. errans within estuarine environments, we examined the distribution of C. errans on Dungeness crabs within Oregon's Coos Bay Estuary. Year-round sampling over a three-year period also allowed us to test for temporal variation in the parasite's distribution. We found that parasite prevalence, mean intensity, and parasite density of C. errans infecting C. magister varied along a clear estuarine gradient, with crabs nearest the ocean carrying the heaviest parasite loads. Larger crabs were more heavily infected with worms, and seasonal infection patterns were observed at some sites within the bay. Crabs sampled from coastal waters near the estuary carried significantly more worms than did crabs from the bay, suggesting that the estuary is acting as a spatiotemporal parasite refuge for this important fishery species.

  20. Drivers of barotropic and baroclinic exchange through an estuarine navigation channel in the Mississippi River Delta Plain

    Science.gov (United States)

    Snedden, Gregg

    2016-01-01

    Estuarine navigation channels have long been recognized as conduits for saltwater intrusion into coastal wetlands. Salt flux decomposition and time series measurements of velocity and salinity were used to examine salt flux components and drivers of baroclinic and barotropic exchange in the Houma Navigation Channel, an estuarine channel located in the Mississippi River delta plain that receives substantial freshwater inputs from the Mississippi-Atchafalaya River system at its inland extent. Two modes of vertical current structure were identified from the time series data. The first mode, accounting for 90% of the total flow field variability, strongly resembled a barotropic current structure and was coherent with alongshelf wind stress over the coastal Gulf of Mexico. The second mode was indicative of gravitational circulation and was linked to variability in tidal stirring and the horizontal salinity gradient along the channel’s length. Tidal oscillatory salt flux was more important than gravitational circulation in transporting salt upestuary, except over equatorial phases of the fortnightly tidal cycle during times when river inflows were minimal. During all tidal cycles sampled, the advective flux, driven by a combination of freshwater discharge and wind-driven changes in storage, was the dominant transport term, and net flux of salt was always out of the estuary. These findings indicate that although human-made channels can effectively facilitate inland intrusion of saline water, this intrusion can be minimized or even reversed when they are subject to significant freshwater inputs.

  1. Fish impingement at estuarine power stations and its significance to commercial fishing

    International Nuclear Information System (INIS)

    Turnpenny, A.W.H.

    1989-01-01

    The abstraction of cooling water (CW) at power stations sited on tidal waters inevitably leads to mortalities of some fish which are drawn in with the CW supply and become impinged on the intake screens. These fish are predominantly 0- or 1-group juveniles which, owing to their small size, are unable to resist intake currents. Commercial fishermen often object to the fact that juvenile fish are killed in this way. Their concern stems from the fact that in order to protect stocks, commercial fishing is restricted to fish which are above a statutory minimum landing size, whereas the majority of fish killed by impingement are below this size. This Report considers the significance of impingement mortalities at four estuarine sites in Britain for six commercially important species. Life tables are used to establish expected survival trajectories for each species and to compute reproductive potential. Each fish killed on intake screens is then considered in terms of the fraction of the reproductive potential of a single adult at maturity, and is ascribed an 'adult equivalent' value. Total catches of mixed juveniles and adults are then presented as 'adult equivalent' values. (author)

  2. Seasonal variability of salinity and circulation in a silled estuarine fjord: A numerical model study

    Science.gov (United States)

    Kawase, Mitsuhiro; Bang, Bohyun

    2013-12-01

    A three-dimensional hydrodynamic model is used to study seasonal variability of circulation and hydrography in Hood Canal, Washington, United States, an estuarine fjord that develops seasonally hypoxic conditions. The model is validated with data from year 2006, and is shown to be capable of quantitatively realistic simulation of hydrographic variability. Sensitivity experiments show the largest cause of seasonal variability to be that of salinity at the mouth of the fjord, which drives an annual deep water renewal in late summer-early autumn. Variability of fresh water input from the watershed also causes significant but secondary changes, especially in winter. Local wind stress has little effect over the seasonal timescale. Further experiments, in which one forcing parameter is abruptly altered while others are kept constant, show that outside salinity change induces an immediate response in the exchange circulation that, however, decays as a transient as the system equilibrates. In contrast, a change in the river input initiates gradual adjustment towards a new equilibrium value for the exchange transport. It is hypothesized that the spectral character of the system response to river variability will be redder than to salinity variability. This is demonstrated with a stochastically forced, semi-analytical model of fjord exchange circulation. While the exchange circulation in Hood Canal appears less sensitive to the river variability than to the outside hydrography at seasonal timescales, at decadal and longer timescales both could become significant factors in affecting the exchange circulation.

  3. The macrobenthic fauna at two point sources of pollution in estuarine Lagos lagoon of southwestern Nigeria.

    Science.gov (United States)

    Ogunwenmo, Christiana A; Okuonghae, Omoruyi; Olofin, Imole; Chilaka, Gerald

    2005-06-01

    Benthic, water and sediment samples were collected at Okobaba, a sawmill site, and Iddo, a sewage dumpage site, in an open estuarine lagoon, in southwestern Nigeria during two periods (December 1999-May 2000 and April 2002-September 2002). Air, surface and bottom water temperatures were high (23.9-32.0 degrees C). Dissolved oxygen (DO) was between 3.4-5.3 mg/l, while biochemical oxygen demand (BOD) varied between 18.0 and 30.0 mg/l at Iddo and, 7.5 and 8.6 mg/l at Okobaba. The pH was alkaline throughout the sampling period at the two sites (7.3-8.6) while, rainfall was between 0.00 and 372.1 mm. Sediment ranged from mud, sandy mud, muddy sand to sandy type. Density and diversity of macrobenthic fauna were low and representative of Polychaeta, Mollusca and Arthropoda. Factors affecting the dynamics and reduction of species in the two communities were discussed.

  4. Determination of the total concentration and speciation of metal ions in river, estuarine and seawater samples.

    Science.gov (United States)

    Alberti, Giancarla; Biesuz, Raffaela; Pesavento, Maria

    2008-12-01

    Different natural water samples were investigated to determine the total concentration and the distribution of species for Cu(II), Pb(II), Al(III) and U(VI). The proposed method, named resin titration (RT), was developed in our laboratory to investigate the distribution of species for metal ions in complex matrices. It is a competition method, in which a complexing resin competes with natural ligands present in the sample to combine with the metal ions. In the present paper, river, estuarine and seawater samples, collected during a cruise in Adriatic Sea, were investigated. For each sample, two RTs were performed, using different complexing resins: the iminodiacetic Chelex 100 and the carboxylic Amberlite CG50. In this way, it was possible to detect different class of ligands. Satisfactory results have been obtained and are commented on critically. They were summarized by principal component analysis (PCA) and the correlations with physicochemical parameters allowed one to follow the evolution of the metals along the considered transect. It should be pointed out that, according to our findings, the ligands responsible for metal ions complexation are not the major components of the water system, since they form considerably weaker complexes.

  5. Seasonal Prevalence of Enteropathogenic Vibrio and Their Phages in the Riverine Estuarine Ecosystem of South Bengal.

    Science.gov (United States)

    Mookerjee, Subham; Batabyal, Prasenjit; Sarkar, Madhumanti Halder; Palit, Anup

    2015-01-01

    Diarrheal disease remains an unsolved problem in developing countries. The emergence of new etiological agents (non-cholera vibrios) is a major cause of concern for health planners. We attempted to unveil the seasonal dynamics of entero-pathogenic Vibrios in Gangetic riverine-estuarine ecosystem. 120 surface water samples were collected for a period of one year from 3 sampling sites on the Hooghly river. Five enteropathogenic Vibrio species, V. cholerae (35%), V. parahaemolyticus (22.5%), V. mimicus (19.1%), V. alginolyticus (15.8%) and V. vulnificus (11.6%), were present in the water samples. The vibriophages, V. vulnificus ɸ (17.5%), V. alginolyticus ɸ (17.5%), V. parahaemolyticus ɸ (10%), V. cholerae non-O1/O139 ɸ (26.6%) and V. mimicus ɸ (9.1%), were also detected in these samples. The highest number of Vibrios were noted in the monsoon (20-34°C), and to a lesser extent, in the summer (24-36°C) seasons. Samples positive for phages for any of the identified Vibrio species were mostly devoid of that particular bacterial organism and vice versa. The detection of toxin genes and resistance to β-lactam antibiotics in some environmental enteropathogenic Vibrio species in the aquatic niches is a significant outcome. This finding is instrumental in the south Bengal diarrhoeal incidence.

  6. Seasonal Prevalence of Enteropathogenic Vibrio and Their Phages in the Riverine Estuarine Ecosystem of South Bengal.

    Directory of Open Access Journals (Sweden)

    Subham Mookerjee

    Full Text Available Diarrheal disease remains an unsolved problem in developing countries. The emergence of new etiological agents (non-cholera vibrios is a major cause of concern for health planners. We attempted to unveil the seasonal dynamics of entero-pathogenic Vibrios in Gangetic riverine-estuarine ecosystem. 120 surface water samples were collected for a period of one year from 3 sampling sites on the Hooghly river. Five enteropathogenic Vibrio species, V. cholerae (35%, V. parahaemolyticus (22.5%, V. mimicus (19.1%, V. alginolyticus (15.8% and V. vulnificus (11.6%, were present in the water samples. The vibriophages, V. vulnificus ɸ (17.5%, V. alginolyticus ɸ (17.5%, V. parahaemolyticus ɸ (10%, V. cholerae non-O1/O139 ɸ (26.6% and V. mimicus ɸ (9.1%, were also detected in these samples. The highest number of Vibrios were noted in the monsoon (20-34°C, and to a lesser extent, in the summer (24-36°C seasons. Samples positive for phages for any of the identified Vibrio species were mostly devoid of that particular bacterial organism and vice versa. The detection of toxin genes and resistance to β-lactam antibiotics in some environmental enteropathogenic Vibrio species in the aquatic niches is a significant outcome. This finding is instrumental in the south Bengal diarrhoeal incidence.

  7. Selenium in aquatic biota inhabiting agricultural drains in the Salton Sea Basin, California

    Science.gov (United States)

    Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.

    2012-01-01

    Resource managers are concerned that water conservation practices in irrigated farmlands along the southern border of the Salton Sea, Imperial County, California, could increase selenium concentrations in agricultural drainwater and harm the desert pupfish (Cyprinodon macularius), a federally protected endangered species. As part of a broader attempt to address this concern, we conducted a 3-year investigation to collect baseline information on selenium concentrations in seven agricultural drains inhabited by pupfish. We collected water, sediment, selected aquatic food-chain taxa (particulate organic detritus, filamentous algae, net plankton, and midge [Chironomidae] larvae), and two poeciliid fishes (western mosquitofish Gambusia affinis and sailfin molly Poecilia latipinna) for selenium determinations. The two fish species served as ecological surrogates for pupfish, which we were not permitted to sacrifice. Dissolved selenium ranged from 0.70 to 32.8 μg/L, with selenate as the major constituent. Total selenium concentrations in other environmental matrices varied widely among drains, with one drain (Trifolium 18) exhibiting especially high concentrations in detritus, 5.98–58.0 μg Se/g; midge larvae, 12.7–50.6 μg Se/g; mosquitofish, 13.2–20.2 μg Se/g; and mollies, 12.8–30.4 μg Se/g (all tissue concentrations are based on dry weights). Although toxic thresholds for selenium in fishes from the Salton Sea are still poorly understood, available evidence suggests that ambient concentrations of this element may not be sufficiently elevated to adversely affect reproductive success and survival in selenium-tolerant poeciliids and pupfish.

  8. Some Physiological Adaptations to Drought in Xerohalophytic Plants Inhabiting Two Oases in Western Desert of Egypt

    International Nuclear Information System (INIS)

    Rayan, A M; Farghali, K A

    2007-01-01

    Under natural drought, some physiological parameters were measured in some wild species inhabiting the western desert of Egypt. Seasonal changes of nitrogen metabolites and Na/K ratio were detected in the investigated species. Effect of seasons, species, and their interaction played an important role on total free amino acids, soluble proteins and Na/K ratio at two oases (Dakhla and Kharga). Species diversity showed more effective variable in regulating such metabolites at Kharga oasis. Plants responded to their environment in two ways, either by increasing their water binding molecules or by preventing the formation of amino acids into proteins. Some of the halophytic and xerophytic species may adjust osmotically to stress by the contribution of nitrogen metabolites. On the other hand, Zygophyllum coccineum, the succulent plant, may adapt to environmental conditions through the accumulation of free amino acids. Correlation analysis between Na+/K+ ratio with free amino acids, soluble proteins and water content in Tamarix aphylla, Salsola imbricata, Balanites aegyptiaca, Trichodesma africanum, and Z. coccineum (Kharga) indicated changes in ionic fraction or accumulating soluble organic compounds which were osmotically active and contribute to osmotic adjustment. Correlations were found between chlorophyll content, ionic and nitrogen metabolites. In Acacia nilotica, Suaeda monoica and Z. coccineum at Dakhla oasis, changes in soluble proteins or ionic ratio could be caused by chlorophyll response to stress, while S. imbricata and T. aphylla may control cellular protein contents. On the other hand, the sharing of both free amino acids and ionic fraction may play an important role of osmoregulation in S. imbricata, Citrullus colocynthis and Z. coccineum at Kharga oasis. (author)

  9. Hematological characteristics of Delminichthys ghetaldii (Steindachner 1882 inhabiting the karst region of eastern Herzegovina

    Directory of Open Access Journals (Sweden)

    Dekić R.

    2014-01-01

    Full Text Available Hematological parameters are a valuable means of estimating the physiological status of fish and, indirectly, the state of their habitat. In order to use blood parameters as biomarkers, it is necessary to know their normal values and the referential intervals for a species. Such investigations are especially valuable in endemic and endangered fish species. In this study, parameters of erythrocyte lineage of Delminichthys ghetaldii (Steindachner 1882, an endemic species inhabiting the karst waters of eastern Herzegovina, were investigated. Fish were caught by nets in the region of Fatničko polje (Fatnica field after the water outflow in March 2013, blood was taken by heart puncture and erythrocyte parameters were determined. Their mean values were as follows: the number of erythrocyte (RBC = 1.474 x 1012/l; hemoglobin concentration (Hb = 72.50 g/l; packed cell volume (PCV = 0.398 l/l; mean corpuscular volume (MCV = 271.19 fl; mean corpuscular hemoglobin (MCH = 49.36 pg, and mean corpuscular hemoglobin concentration (MCHC = 193.16 g/l eryt. Body mass and morphometric features were also estimated and their mean values were: body mass = 25.49 g, total and standard body length = 14.13 cm and 11.98 cm, respectively, Fulton coefficient = 1.45. For the values of all parameters, the normality of distribution was tested, as well as differences between mean values of males and females. Pearson’s correlation and multiple regression analyses between mass, morphometric and hematological parameters have shown that erythrocyte parameters may influence body mass and of morphometric characteristics in this species.

  10. Sub-hourly changes in biogeochemical properties in surface waters of Zuari estuary, Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Anand, S.S.; Anju, K.J.; Mathew, D.; DileepKumar, M.

    -hourly changes in surface waters dissolved oxygen, nutrients, and pigments are measurable and significant in an estuarine system. Tidal circulation has been found to strongly influence the observed changes and has implications to material fluxes in and out...

  11. A report on the occurrence of Thraustochytrid species in Indian waters

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, S.; Raghukumar, C.

    (Ulken) Gaertner. The substrata examined were decaying mangrove leaves, living algae, estuarine, and offshore water samples, phytoplankton samples, gill tissues of green mussels, hydroid polyps, detritus samples, scrapings of oyster shell, coral polyps...

  12. Resting eggs in free living marine and estuarine copepods

    DEFF Research Database (Denmark)

    Holm, Mark Wejlemann; Kiørboe, Thomas; Brun, Philipp Georg

    2018-01-01

    for 42 species of marine free living copepods. Resting eggs are reported in areas with high seasonal variation in sea surface temperature (median range 11°C). Temporal variation in chlorophyll a concentrations, however, seems of less importance. Resting eggs are commonly produced to cope with both warm......Marine free living copepods can survive harsh periods and cope with seasonal fluctuations in environmental conditions using resting eggs (embryonic dormancy). Laboratory experiments show that temperature is the common driver for resting egg production. Hence, we hypothesize (i) that seasonal...... temperature variation, rather than variation in food abundance is the main driver for the occurrence of the resting eggs strategy in marine and estuarine copepod species; and (ii) that the thermal boundaries of the distribution determine where resting eggs are produced and whether they are produced to cope...

  13. Physico-chemical characteristics of the Mahanadi estuarine ecosystem, east coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Upadhyay, S.

    Seasonal pattern of temperature, salinity, pH, dissolved oxygen, phosphate, nitrate and silicate profiles of the Mahanadi estuary have been studied. On the basis of physical characteristics, Mahanadi estuarine system can be classified as a partially...

  14. Behaviour of fluoride and dissolved silicon in Gouthami Godavari estuarine environment

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.; Sudhakar, U.; Varaprasad, S.J.D.

    The concentrations of fluoride and dissolved silicon in Gouthami-Godavari estuarine region (Andhra Pradesh, India) have been measured as a function of chlorinity during different seasons. Fluoride and dissolved silicon behave conservatively during...

  15. Evaluating Hyperspectral Imaging of Wetland Vegetation as a Tool for Detecting Estuarine Nutrient Enrichment

    Science.gov (United States)

    2008-05-01

    exchanges. Collectively, these studies suggest that estuarine vegetation has considerable potential as a practical bioindicator of temporal nutrient... bioindicators of potential eutrophication in the field and at landscape scales. Most previous work on spectral responses to nutrient enrichment has been

  16. Relationship between benthic foraminifera and sediment in the estuarine complex of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Dalal, S.G.

    Two indices of community association were used to elucidate the relationship between changes in species composition of benthic foraminifera and changes in the grain size composition of the sediment in estuarine complex of Goa. The degree...

  17. Ecological periodic tables for nekton and benthic macrofaunal community usage of estuarine habitats Slides

    Science.gov (United States)

    Ecological periodic tables for nekton and benthic macrofaunal community usage of estuarine habitats Steven P. Ferraro, U.S. Environmental Protection Agency, Newport, OR Background/Questions/Methods The chemical periodic table, the Linnaean system of classification, and the Her...

  18. Estuarine Living Marine Resources: Gulf of Mexico Regional Distribution and Abundance (NCEI Accession 0163993)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is the original (1992) Gulf of Mexico regional component of NOAA's Estuarine Living Marine Resources (ELMR) Project, a national database of ecologically and...

  19. Organic matter - A key factor in controlling mercury distribution in estuarine sediment

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, P.; Sarkar, A.; Vudamala, K.; Naik, R.; Nath, B.N.

    Organic matter (OM) was found to play an important role in controlling mercury (Hg) distribution and speciation in estuarine sediment of the Vembanad Lake. The sedimentary organic carbon (OC) from the northern part of the lake was influenced mainly...

  20. Microbial community structure of surface sediments from a tropical estuarine environment using next generation sequencing

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.; Kuchi, N.; Kale, D.; Anil, A.C.

    Microbial community structure was analyzed from tropical monsoon influenced Mandovi-Zuari (Ma-Zu) estuarine sediment by means of Next Gen Sequencing (NGS) approach using Ion Torrent PGM™. The sequencing generated 80,282 raw sequence reads. Barcoding...

  1. Estuarine Living Marine Resources: Southeast Regional Distribution and Abundance (NCEI Accession 0163992)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is the original (1991) Southeast regional component of NOAA's Estuarine Living Marine Resources (ELMR) Project, a national database of ecologically and...

  2. Residual estuarine circulation in the Mandovi, a monsoonal estuary: A three-dimensional model study

    Digital Repository Service at National Institute of Oceanography (India)

    Vijith, V.; Shetye, S.R.; Baetens, K.; Luyten, P.; Michael, G.S.

    then analyse the model results to define characteristics of residual estuarine circulation in the Mandovi. Our motivation to study this aspect of the Mandovi`s dynamics is derived from the following three considerations. First, residual circulation is important...

  3. A multi-method approach for the study of lanthanum speciation in coastal and estuarine sediments

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, P.; Babu, P.V.R.; Sarma, V.V.

    Two independent analytical methods (sequential extraction and kinetic extraction methods) were applied in order to understand the distribution and speciation of La in the coastal and estuarine sediments from the central east coast of India...

  4. Environmental impact assessment of benthic community stability in an estuarine complex

    Digital Repository Service at National Institute of Oceanography (India)

    Ansari, Z.A.; Abidi, S.A.H.

    . There was also a substantial decrease in clam production during the 10 year time under consideration. The implication of ever increasing mining rejects in the estuarine system and the utilization of quantitative benthic parameters in environmental impact studies...

  5. Estuarine Living Marine Resources: North Atlantic Regional Distribution and Abundance (NCEI Accession 0162402)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is the North Atlantic regional component of NOAA’s Estuarine Living Marine Resources (ELMR) Project, a national database of ecologically and economically...

  6. Estuarine Living Marine Resources: West Coast Regional Distribution and Abundance (NCEI Accession 0161540)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is the West Coast regional component of NOAA’s Estuarine Living Marine Resources (ELMR) Project, a national database of ecologically and economically...

  7. Estuarine Living Marine Resources: Mid-Atlantic Regional Distribution and Abundance (NCEI Accession 0162403)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is the Mid-Atlantic regional component of NOAA’s Estuarine Living Marine Resources (ELMR) Project, a national database of ecologically and economically...

  8. Seasonal patterns of phytoplankton biomass and productivity in a tropical estuarine complex (west coast of India)

    Digital Repository Service at National Institute of Oceanography (India)

    Devassy, V.P.; Goes, J.I.

    Phytoplankton cell numbers and chlorophyll a determinations were made during the premonsoon, monsoon and postmonsoon periods in the Mandovi-Zuari estuarine complex (west coast of India). Primary productivity estimates agreed well with chlorophyll a...

  9. Genetic architecture of evolved tolerance to PCBs in the estuarine fish Fundulus heteroclitus

    Science.gov (United States)

    Populations of Atlantic killifish (F. heteroclitus) resident to coastal estuarine habitats contaminated with halogenated aromatic hydrocarbons (HAHs) exhibit heritable resistance to the early life-stage toxicity associated with these compounds. Beyond our knowledge of the aryl hy...

  10. Abundance, stock origin, and length of marked and unmarked juvenile Chinook salmon in the surface waters of greater Puget Sound

    Science.gov (United States)

    Rice, C.A.; Greene, C.M.; Moran, P.; Teel, D.J.; Kuligowski, D.R.; Reisenbichler, R.R.; Beamer, E.M.; Karr, J.R.; Fresh, K.L.

    2011-01-01

    This study focuses on the use by juvenile Chinook salmon Oncorhynchus tshawytscha of the rarely studied neritic environment (surface waters overlaying the sublittoral zone) in greater Puget Sound. Juvenile Chinook salmon inhabit the sound from their late estuarine residence and early marine transition to their first year at sea. We measured the density, origin, and size of marked (known hatchery) and unmarked (majority naturally spawned) juveniles by means of monthly surface trawls at six river mouth estuaries in Puget Sound and the areas in between. Juvenile Chinook salmon were present in all months sampled (April-November). Unmarked fish in the northern portion of the study area showed broader seasonal distributions of density than did either marked fish in all areas or unmarked fish in the central and southern portions of the sound. Despite these temporal differences, the densities of marked fish appeared to drive most of the total density estimates across space and time. Genetic analysis and coded wire tag data provided us with documented individuals from at least 16 source populations and indicated that movement patterns and apparent residence time were, in part, a function of natal location and time passed since the release of these fish from hatcheries. Unmarked fish tended to be smaller than marked fish and had broader length frequency distributions. The lengths of unmarked fish were negatively related to the density of both marked and unmarked Chinook salmon, but those of marked fish were not. These results indicate more extensive use of estuarine environments by wild than by hatchery juvenile Chinook salmon as well as differential use (e.g., rearing and migration) of various geographic regions of greater Puget Sound by juvenile Chinook salmon in general. In addition, the results for hatchery-generated timing, density, and length differences have implications for the biological interactions between hatchery and wild fish throughout Puget Sound. ?? American

  11. Development of a Hydrodynamic Model for Skagit River Estuary for Estuarine Restoration Feasibility Assessment

    International Nuclear Information System (INIS)

    Yang, Zhaoqing; Liu, Hedong; Khangaonkar, Tarang P.

    2006-01-01

    The Skagit River is the largest river in the Puget Sound estuarine system. It discharges about 39% of total sediment and more than 20% of freshwater into Puget Sound. The Skagit River delta provides rich estuarine and freshwater habitats for salmon and many other wildlife species. Over the past 150 years, economic development in the Skagit River delta has resulted in significant losses of wildlife habitat, particularly due to construction of dikes. Diked portion of the delta is known as Fir Island where irrigation practices for agriculture land over the last century has resulted in land subsidence. This has also caused reduced efficiency of drainage network and impeded fish passages through the area. In this study, a three-dimensional tidal circulation model was developed for the Skagit River delta to assist estuarine restoration in the Fir Island area. The hydrodynamic model used in the study is the Finite Volume Coastal Ocean Model (FVCOM). The hydrodynamic model was calibrated using field data collected from the study area specifically for the model development. Wetting and drying processes in the estuarine delta are simulated in the hydrodynamic model. The calibrated model was applied to simulate different restoration alternatives and provide guidance for estuarine restoration and management. Specifically, the model was used to help select and design configurations that would improve the supply of sediment and freshwater to the mudflats and tidal marsh areas outside of diked regions and then improve the estuarine habitats for salmon migration

  12. Estuarine development and early Holocene transgression across an aeolianite substrate, Caesarea, central Israel

    Science.gov (United States)

    Goff, John A.; Austin, James A.; Goodman-Tchernov, Beverly N.

    2018-04-01

    Estuaries are important features on the coastal landscape due to their potential for rich, diverse, and abundant resources. The modern coast of the southeast Mediterranean is largely devoid of estuaries except in rare circumstances where ample sands are delivered to the shore, such as east of the Nile Delta. Whether or not today's condition is reflective of that present during lower sea-levels is greatly speculative in part due to a dearth of high-resolution sub-surface mapping in the shallower (sea-level curves, was a period of rapid ( 1-1.7 cm/yr) sea-level rise. Now-submerged aeolianite ridges (locally referred to as 'kurkar'), cemented aeolian deposits formed during pre-Last-Glacial-Maximum (LGM) seaward advance (regression) of the coastline, likely provided some offshore barrier for estuarine development. These were insufficient, however, to account for all the estuarine deposition interpreted, leading us to hypothesize that sand-constructed barrier islands were also present as sea-level rose during the Holocene. This supply of sand, clearly greater than what is evident today, could have originated from sea-level rise phase eroding Nile Delta sediments transported northward by littoral currents, or from increased output from local rivers during wetter climatic conditions. We also observe a transition from linear, shore-parallel aeolianite ridge morphology features on land and in shallow water, to nested, arcuate features below 30 mbsl. Whereas the linear ridges are thought to be coastal foredune remnants abandoned by the retreating shoreline, the arcuate forms resemble fossil parabolic (blowout) dunes. Based on the recent initiation of parabolic dunes on Cape Cod following anthropogenic denudation of forests there, we suggest that climate aridification approaching the LGM could have denuded vegetation along the Israeli coast, enabling parabolic dune formation landward of the coastal foredunes which were later preserved via cementation. Understanding the past

  13. Partitioning of metals in different binding phases of tropical estuarine sediments: importance of metal chemistry.

    Science.gov (United States)

    Chakraborty, Parthasarathi; Chakraborty, Sucharita; Vudamala, Krushna; Sarkar, Arindam; Nath, B Nagender

    2016-02-01

    Distribution of metals in different binding phases of estuarine sediments provides chemically significant description of metal-sediment interactions. This study describes the influences of ligand field stabilization energy (LFSE), Jahn-Teller effect, and water exchange rate (k-w) on metal distribution in different binding phases of estuarine sediments. It was found that Cu had highest affinity for organic binding phases in the studied sediments followed by Ni and Pb. However, Pb showed strong association with Fe/Mn oxide phases followed by Ni and Cu. Faster k-w of Cu (II) (1 × 10(9) s(-1)) increased the rate of complex formation of Cu(2+) ion with ligand in the organic phases. The Cu-ligand (from organic phase) complexes gained extra stability by the Jahn-Teller effect. The combined effects of these two phenomena and high ionic potential increased the association of Cu with the organic phases of the sediments than Ni and Pb. The smaller ionic radii of Ni(2+) (0.72 Å) than Pb(2+) (1.20 Å) increase the stability of Ni-ligand complexes in the organic phase of the sediments. High LFSE of Ni(II) (compared with Pb(2+) ions) also make Ni-organic complexes increasingly stable than Pb. High k-w (7 × 10(9) s(-1)) of Pb did not help it to associate with organic phases in the sediments. The high concentration of Pb in the Fe/Mn oxyhydroxide binding phase was probably due to co-precipitation of Pb(2+) and Fe(3+). High surface area or site availability for Pb(2+) ion on Fe oxyhydroxide phase was probably responsible for the high concentration of Pb in Fe/Mn oxyhydroxide phase. Increasing concentrations of Cu in organic phases with the increasing Cu loading suggest that enough binding sites were available for Cu in the organic binding phases of the sediments. This study also describes the influence of nature of sedimentary organic carbon (terrestrial and marine derived OC) in controlling these metal distribution and speciation in marine sediment.

  14. Barrier-island and estuarine-wetland physical-change assessment after Hurricane Sandy

    Science.gov (United States)

    Plant, Nathaniel G.; Smith, Kathryn E.L.; Passeri, Davina L.; Smith, Christopher G.; Bernier, Julie C.

    2018-04-03

    estimated from observations. The scope includes understanding changes caused by both short- and long-term processes using both remotely sensed and in situ observations to characterize changes to the wetland in terms of accretion/expansion and erosion/contraction. Accretion may be due to net vertical and (or) horizontal deposition, including estuarine-shoreline change due to overwash. Wetland erosion may be due to elevated waves and water levels in the estuary itself. We included additional information based on wave runup and storm-surge elevations based on models and elevation data. We then developed a predictive assessment for wetland vulnerability that describes the likelihood of changes of the estuarine shoreline and the landward extent of sand overwash driven by processes occurring on the ocean-facing shoreline. This assessment is intended to be linked to the beach and dune vulnerability assessments that have been developed previously.

  15. Microplastics in four estuarine rivers in the Chesapeake Bay, U.S.A.

    Science.gov (United States)

    Yonkos, Lance T; Friedel, Elizabeth A; Perez-Reyes, Ana C; Ghosal, Sutapa; Arthur, Courtney D

    2014-12-16

    Once believed to degrade into simple compounds, increasing evidence suggests plastics entering the environment are mechanically, photochemically, and/or biologically degraded to the extent that they become imperceptible to the naked eye yet are not significantly reduced in total mass. Thus, more and smaller plastics particles, termed microplastics, reside in the environment and are now a contaminant category of concern. The current study tested the hypotheses that microplastics concentration would be higher in proximity to urban sources, and vary temporally in response to weather phenomena such as storm events. Triplicate surface water samples were collected approximately monthly between July and December 2011 from four estuarine tributaries within the Chesapeake Bay, U.S.A. using a manta net to capture appropriately sized microplastics (operationally defined as 0.3-5.0 mm). Selected sites have watersheds with broadly divergent land use characteristics (e.g., proportion urban/suburban, agricultural and/or forested) and wide ranging population densities. Microplastics were found in all but one of 60 samples, with concentrations ranging over 3 orders of magnitude (560 g/km(2)). Concentrations demonstrated statistically significant positive correlations with population density and proportion of urban/suburban development within watersheds. The greatest microplastics concentrations also occurred at three of four sites shortly after major rain events.

  16. Contribution of Spartina maritima to the reduction of eutrophication in estuarine systems

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, Ana I. [IO - Institute of Oceanography, Faculty of Sciences, University of Lisbon, Campo Grande, 1749-016 Lisbon (Portugal); IMAR - Institute of Marine Research, Department of Zoology, University of Coimbra, 3004-517 Coimbra (Portugal)], E-mail: aisousa@fc.ul.pt; Lillebo, Ana I. [CESAM - Centro de Estudos do Ambiente e do Mar, Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro (Portugal); Cacador, Isabel [IO - Institute of Oceanography, Faculty of Sciences, University of Lisbon, Campo Grande, 1749-016 Lisbon (Portugal); Pardal, Miguel A. [IMAR - Institute of Marine Research, Department of Zoology, University of Coimbra, 3004-517 Coimbra (Portugal)

    2008-12-15

    Salt marshes are among the most productive ecosystems in the world, performing important ecosystem functions, particularly nutrient recycling. In this study, a comparison is made between Mondego and Tagus estuaries in relation to the role of Spartina maritima in nitrogen retention capacity and cycling. Two mono-specific S. maritima stands per estuary were studied during 1 yr (biomass, nitrogen (N) pools, litter production, decomposition rates). Results showed that the oldest Tagus salt marsh population presented higher annual belowground biomass and N productions, and a slower decomposition rate for litter, contributing to the higher N accumulation in the sediment, whereas S. maritima younger marshes had higher aboveground biomass production. Detritus moved by tides represented a huge amount of aboveground production, probably significant when considering the N balance of these salt marshes. Results reinforce the functions of salt marshes as contributing to a reduction of eutrophication in transitional waters, namely through sedimentation processes. - The crucial capacity of salt marshes to retain nitrogen, thus reducing eutrophication, greatly depends on the salt marsh maturity, rather than the estuarine system.

  17. Systemic Homeostasis in Metabolome, Ionome, and Microbiome of Wild Yellowfin Goby in Estuarine Ecosystem.

    Science.gov (United States)

    Wei, Feifei; Sakata, Kenji; Asakura, Taiga; Date, Yasuhiro; Kikuchi, Jun

    2018-02-22

    Data-driven approaches were applied to investigate the temporal and spatial changes of 1,022 individuals of wild yellowfin goby and its potential interaction with the estuarine environment in Japan. Nuclear magnetic resonance (NMR)-based metabolomics revealed that growth stage is a primary factor affecting muscle metabolism. Then, the metabolic, elemental and microbial profiles of the pooled samples generated according to either the same habitat or sampling season as well as the river water and sediment samples from their habitats were measured using NMR spectra, inductively coupled plasma optical emission spectrometry and next-generation 16 S rRNA gene sequencing. Hidden interactions in the integrated datasets such as the potential role of intestinal bacteria in the control of spawning migration, essential amino acids and fatty acids synthesis in wild yellowfin goby were further extracted using correlation clustering and market basket analysis-generated networks. Importantly, our systematic analysis of both the seasonal and latitudinal variations in metabolome, ionome and microbiome of wild yellowfin goby pointed out that the environmental factors such as the temperature play important roles in regulating the body homeostasis of wild fish.

  18. Santos estuarine sediments, Brazil - metal and trace element assessment by neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Amorim, Eduardo P.; Favaro, Deborah I.T., E-mail: ducamorim@yahoo.com.b, E-mail: defavaro@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP) Sao Paulo, SP (Brazil); Berbel, Glaucia; Braga, Elisabete S., E-mail: edsbraga@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Inst. Oceanografico. Lab. de Nutrientes, Micronutrientes e Tracos nos Oceanos (LABNUT)

    2009-07-01

    The Santos estuary system is an intricate pattern of tidal channels and small rivers originating from the adjacent Pre-Cambrian slopes. These two major estuaries share a common area in the upper portion of the region which interacts with each other. The largest harbor in Latin America is located at the eastern outlet of the Santos estuary. This intricate and sensitive ecosystem is highly susceptible to human impact from industrial activities, urban sewage and polluted solid wastes disposal. Due to its high vulnerability CETESB (Environmental Control Agency of the Sao Paulo State) sporadically monitors the contamination levels of water, sediment and marine organisms in this region. The present study reports results concerning the distribution of some major, trace and rare earth elements in the Santos estuarine marine sediments. Thirty two bottom sediment samples (SS0601 to SS0616 (summer) and SW0601 to SW0616 (winter) were collected in this estuary, including regions of Sao Vicente, Santos, Cubatao and Vicente de Carvalho, by a vanVeen sampler in the summer and winter of 2006. Multielemental analysis was carried out by instrumental neutron activation analysis (INAA). The concentration values obtained for As and metals Cr and Zn in the sediment samples were compared to Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL values) and are adopted by CETESB. (author)

  19. Santos estuarine sediments, Brazil - metal and trace element assessment by neutron activation analysis

    International Nuclear Information System (INIS)

    Amorim, Eduardo P.; Favaro, Deborah I.T.; Berbel, Glaucia; Braga, Elisabete S.

    2009-01-01

    The Santos estuary system is an intricate pattern of tidal channels and small rivers originating from the adjacent Pre-Cambrian slopes. These two major estuaries share a common area in the upper portion of the region which interacts with each other. The largest harbor in Latin America is located at the eastern outlet of the Santos estuary. This intricate and sensitive ecosystem is highly susceptible to human impact from industrial activities, urban sewage and polluted solid wastes disposal. Due to its high vulnerability CETESB (Environmental Control Agency of the Sao Paulo State) sporadically monitors the contamination levels of water, sediment and marine organisms in this region. The present study reports results concerning the distribution of some major, trace and rare earth elements in the Santos estuarine marine sediments. Thirty two bottom sediment samples (SS0601 to SS0616 (summer) and SW0601 to SW0616 (winter) were collected in this estuary, including regions of Sao Vicente, Santos, Cubatao and Vicente de Carvalho, by a vanVeen sampler in the summer and winter of 2006. Multielemental analysis was carried out by instrumental neutron activation analysis (INAA). The concentration values obtained for As and metals Cr and Zn in the sediment samples were compared to Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL values) and are adopted by CETESB. (author)

  20. Short-term variability of fish condition and growth in estuarine and shallow coastal areas.

    Science.gov (United States)

    Duarte, Irina A; Vasconcelos, Rita P; França, Susana; Batista, Marisa I; Tanner, Susanne; Cabral, Henrique N; Fonseca, Vanessa F

    2018-03-01

    Short-term variability in condition factor: relative condition factor Kn; biochemical condition: RNA:DNA and protein content; and instantaneous growth rates were determined in estuarine and coastal fish. Dicentrarchus labrax, Solea senegalensis and Pomatoschistus microps were sampled in the Tejo estuary, while Trachurus trachurus was sampled in an adjacent shallow coastal area. Variation of condition indices was more frequent at the week scale (sampling periods with fortnight intervals) than at the daily scale (consecutive days in each sampling period) in all species. Water temperature was correlated with biochemical indices, while salinity showed no effect, evidencing the influence of environmental short-term variation (temperature) on biochemical condition in natural populations. Yet, decreasing individual variability in fish condition was observed along the sampled weeks, resulting in a more homogeneous condition of populations, particularly for T. trachurus likely due to a more stable coastal environment. Biochemical indices proved to be sensitive to short-term environmental variability, despite species-specific responses. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Characterisation of the suspended particulate matter in a stratified estuarine environment employing complementary techniques

    Science.gov (United States)

    Thomas, Luis P.; Marino, Beatriz M.; Szupiany, Ricardo N.; Gallo, Marcos N.

    2017-09-01

    The ability to predict the sediment and nutrient circulation within estuarine waters is of significant economic and ecological importance. In these complex systems, flocculation is a dynamically active process that is directly affected by the prevalent environmental conditions. Consequently, the floc properties continuously change, which greatly complicates the characterisation of the suspended particle matter (SPM). In the present study, three different techniques are combined in a stratified estuary under quiet weather conditions and with a low river discharge to search for a solution to this problem. The challenge is to obtain the concentration, size and flux of suspended elements through selected cross-sections using the method based on the simultaneous backscatter records of 1200 and 600 kHz ADCPs, isokinetic sampling data and LISST-25X measurements. The two-ADCP method is highly effective for determining the SPM size distributions in a non-intrusive way. The isokinetic sampling and the LISST-25X diffractometer offer point measurements at specific depths, which are especially useful for calibrating the ADCP backscatter intensity as a function of the SPM concentration and size, and providing complementary information on the sites where acoustic records are not available. Limitations and potentials of the techniques applied are discussed.

  2. Seasonal change in a filter-feeding bivalve Musculista senhousia population of a eutrophic estuarine lagoon

    Science.gov (United States)

    Yamamuro, Masumi; Hiratsuka, Jun'ichi; Ishitobi, Yu

    2000-10-01

    Filter-feeding bivalves often predominate the benthic biomass of estuaries, although their population size may drastically fluctuate due to physical and biological disturbances. To examine the recovery of a mussel population after periods of severe predation and anoxia, and to estimate the amount of nutrients removed from the system through mussel production, we surveyed, over 2 years, the Musculista senhousia population in the estuarine lagoon, Lake Nakaumi, Japan. Predation by diving ducks ( Aythya fuligula, Aythya ferina and Aythya marila) during winter dramatically reduced the mussel biomass in both years, but recruitment of juvenile mussels sustained the population. Anoxia during the second summer severely reduced the mussel population, resulting in less biomass than in the autumn of the previous year. Potential annual removal of nitrogen and phosphorus from the lagoon water through burial of M. senhousia shells under oxic conditions was estimated to be 7.1 and 5.1 tons, respectively. These are equivalent to 0.7% and 4.9% of the nitrogen and phosphorous annual load entering the lagoon via the main river. Under anoxic conditions, removal would decrease to only 5.6% of the potential amount.

  3. Metals impact into the Paranaguá Estuarine Complex (Brazil during the exceptional flood of 2011

    Directory of Open Access Journals (Sweden)

    Marilia Lopes da Rocha

    Full Text Available Abstract Particulate and dissolved metal concentrations were determined after the largest flood in the last 30 years on the east-west axis of the Paranaguá Estuarine Complex (PEC and compared to the those of the dry period at two stations. Results confirmed that the flood greatly affected riverine outflows and the behavior of metals in the PEC. In particular, a sharp decrease in salinity was followed by extremely high SPM concentrations leading to a decrease in DO concentrations at both stations. For the dissolved phase, ANOSIM analysis showed a significant dissimilarity at each station between the sampled periods, whereas for the particulate phase this dissimilarity was found only for the samplings taken at the Antonina Station. KD values suggested dissolved Cu behavior was related to the presence of organic complexes and dissolved Mn had sediment resuspension of redox sediments and or/pore water injection as sources. Metal concentrations were lower than in polluted estuaries, though high enrichment factors found after the flood pointed to the influence of anthropogenic sources. In conclusion, the flood's influence was more evident at the Antonina Station, due to its location in the upper estuary, whereas in Paranaguá a high SPM content with low metal concentration was found, following the common pattern generally found in other marine systems subject to heavy rainfall events.

  4. Some aspects of biology of Bombay duck, Harpodon nehereus (Ham) inhabiting the coastal waters of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A.; Roy, J.M.; Parulekar, A.H.

    Intensity of feeding was maximum in Harpodon nehereus of size group 2 (15.1-17 cm) with higher feeding in males than in females. About 44.61% of the fish had empty stomachs. The food of the fish chiefly consisted of fish-components (69.83%) followed...

  5. Ma'adim Vallis Estuarine Delta in Elysium Basin and Its Relevance as a Landing Site for Exobiology Exploration on Mars

    Science.gov (United States)

    Grin, E. A.; Cabrol, N. A.

    1998-01-01

    The debouche of Ma'adim Vallis in the Elysium Basin generated a transitional transported sediment structure, which planimetric shape is controlled by the enclosing topography of a deep reentrant gulf of the Basin into the highland. We defined it as an estuarine delta. The location and the importance of this estuarine delta is supported by the theoretical model of graded profile constructed for Ma'adim Vallis, and by two approaches: (i) the reconstruction of Ma'adim Vallis downstream course from Gusev to Elysium Basin, and (ii) the survey of the sediment deposit in the alleged estuary. The longitudinal graded profile of Ma'adim Vallis finds its base-level in the Elysium Basin, at a about 1000 m elevation, which is in agreement with the observed Basin shoreline. This model is supported by observational evidence of flow between the northern rim of Gusev crater, and the Elysium Basin shoreline. This downstream course of Ma'adim Vallis can be divided into three hydrogeologic regions. into three hydrogeologic regions. (a) The first region is a flooded plain (Zephiria Mensae), consisting in chaotic terrain formed by highland rocks, and disintegrated lava of the western flank of Apollinaris. Morphologic indicators of the flood process are: (1) the sediment deposit over the Gusev crater northern rim that reflects the overspilling of the crater-lake water through a 40-km wide gap provided by an ancient impact crater, (2) the tear-drop shaped feature on the northeastern flank of Apollinaris Patera, and (3) the chaotic terrain that suggest the emergence of ground water generated by the seepage of the crater lake through high-permeable broken rampart material. This underground water circulation sustained by the hydrostatic pressure of the crater-lake has likely generated a hydrothermal system in the volcanic environment of Apollinaris Patera. The stratigraphy of the flooded area is identified as Hesperian age, with occurrences of Noachian hilly individual features, and as

  6. Processing of humic-rich riverine dissolved organic matter by estuarine bacteria: effects of predegradation and inorganic nutrients

    DEFF Research Database (Denmark)

    Asmala, E.; Autio, R.; Kaartokallio, H.

    2014-01-01

    inorganic nitrogen and phosphorus than without addition (on average 13.5 % and 9.0, respectively), but had no effect on the degradation of fresh, non-predegraded, DOC (%BDOC 12.0 %). Bacterial growth efficiency (BGE) was highest (65 ± 2 %) in the units with fresh DOM, and lowest in units with predegraded...... of predegradation and the inorganic nutrient status in the receiving estuary has consequences to carbon cycling and will determine the amount of terrestrial-derived DOC being ultimately assimilated into marine food webs......The bioavailability of predegraded dissolved organic matter (DOM) from a humic-rich, boreal river to estuarine bacteria from the Baltic Sea was studied in 39-day bioassays. The river waters had been exposed to various degrees of bacterial degradation by storing them between 0 and 465 days in dark...

  7. Total and extractable elemental composition of the intertidal estuarine biofilm of the Río de la Plata: Disentangling natural and anthropogenic influences

    Science.gov (United States)

    García-Alonso, J.; Lercari, D.; Araujo, B. F.; Almeida, M. G.; Rezende, C. E.

    2017-03-01

    Estuarine transitional waters constitute regions affected by or at risk of anthropogenic impact due to urbanization and industrial development. The elemental composition of the intertidal biofilm sediment is an excellent marker for the detection of any impact, and may exert a bottom-up influence by natural concatenation to higher organization levels (e.g. molecules, cells, organisms, communities). The distribution pattern of elemental composition (total and bioavailable fraction) along the estuary axes was analyzed, disentangling potential shifts produced by human activities. We predict that most abundant elements in the Rio de la Plata estuary are the natural earth-crust components and that these will not show any evident gradient along the estuarine axis. Elements involved in human related processes will shape concentration gradients from the most probable source (i.e. cities) indicating estuarine pollution. The research strategy involved the sampling of intertidal biofilm along the entire estuary and the registration of environmental variables and the total and bioavailable elemental composition. Sampling sites represent pristine, agricultural, and urbanized areas along a 428-km-long coastline comprising the inner, middle and outer Río de la Plata estuarine zones and a coastal fringe of oceanic beaches of Uruguay (South America). Biofilm sediment samples were collected in Autumn 2011 and digested for total and extractable (bioavailable) elements quantification measured by ICP-OES. Mercury (Hg) sediments were digested with aqua regia and quantified by cold vapor atomic absorption (CVAAS). The most abundant elements measured were Al, Fe, and Ca in all sampling. Anthropogenic marker elements such as Hg, Cr, Pb, Zn, and Cu were found, even at potentially toxic levels, at urban beaches at the city of Montevideo. The ordination of samples highlights the distinctive characteristics of urban beaches, placed in a particular location along the first principal component

  8. Impacts of Suspended Sediment and Estuarine - Shelf Exchange Pathways on Shelf Ecosystem Dynamics in the Northern Gulf of Mexico

    Science.gov (United States)

    Wiggert, J. D.; Pan, C.; Dinniman, M. S.; Lau, Y.; Fitzpatrick, P. J.; O'Brien, S. J.; Bouchard, C.; Quas, L. M.; Miles, T. N.; Cambazoglu, M. K.; Dykstra, S. L.; Dzwonkowski, B.; Jacobs, G. A.; Church, I.; Hofmann, E. E.

    2017-12-01

    A circulation model based on the Coupled-Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System, with coupled biogeochemical and sediment transport modules, has been implemented for Mississippi Sound and the adjacent continental shelf region. The model has 400-m horizontal resolution, 24 vertical layers, and includes wetting/drying capability to resolve shallow inshore regions. The circulation model was spun-up using oceanographic initial and lateral boundary conditions provided by a 1-km resolution regional implementation of the Navy Coastal Ocean Model (NCOM) in the Gulf of Mexico. The biogeochemical module includes multiple size classes of phytoplankton, zooplankton and detritus, a fish larvae compartment, and explicitly tracks dissolved oxygen with benthic cycling interaction. The sediment transport model is implemented based on benthic mapping data that provides bottom sediment type distributions and spatio-temporal validation. A regionally specific atmospheric forcing product that provides improved spatial and temporal resolution, including diurnal sea breeze impacts, has been developed and applied. Model experiments focus on periods when comprehensive ship-based sampling was deployed by the CONCORDE (Consortium for Coastal River-Dominated Ecosystems) research program, which was established to investigate the complex fine-scale biological, chemical and physical interactions in a marine system controlled by pulsed-river plume dynamics. Biophysical interactions and biogeochemical variability associated with estuarine - shelf exchanges between nearshore lagoonal estuarine waters and the continental shelf revealed by the model provide new insight into how seasonal variation of hydrological forcing conditions influence ecological and biogeochemical processes in the highly productive Northern Gulf region. Application of the COAWST-based model system with and without inclusion of the sediment transport module demonstrates how suspended sediment in the

  9. Physico-chemical characteristics and circulation of waters in the Mauritius-Seychelles Ridge Zone, southwest Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Ragoonaden, S.; RameshBabu, V.; Sastry, J.S.

    -conservative in this estuary Land runoff coupled with biological and abiological processes appear to have a considerable bearing on the distribution pattern of these micronutrients in this estuarine waters...

  10. Remote Sensing of Selected Water-Quality Indicators with the Hyperspectral Imager for the Coastal Ocean (HICO) Sensor

    Science.gov (United States)

    The Hyperspectral Imager for the Coastal Ocean (HICO) offers the coastal environmental monitoring community an unprecedented opportunity to observe changes in coastal and estuarine water quality across a range of spatial scales not feasible with traditional field-based monitoring...

  11. Method 200.12 - Determination of Trace Elements in Marine Waters by StabilizedTemperature Graphite Furnace Atomic Absorption

    Science.gov (United States)

    This method provides procedures for the determination of total recoverable elements by graphite furnace atomic absorption (GFAA) in marine waters, including estuarine, ocean and brines with salinities of up to 35 ppt.

  12. Analysis of cognitive structure of nuclear energy focusing on inhabiting areas, genders, and knowledge

    International Nuclear Information System (INIS)

    Kimura, Hiroshi; Suzuki, Atsuyuki; Furuta, Kazuo

    2003-01-01

    The purpose of this research is to clarify people's cognitive structure of nuclear energy, and to analyze how the cognitive structure varies with inhabiting areas, genders, and knowledge of nuclear energy. For this purpose, we carried out questionnaire survey of perception of nuclear energy in the urban areas and nuclear power plants (NPP) siting areas. After collecting data, we defined 8 categories in terms of respondents' inhabiting areas, genders, and knowledge, and applied factor analysis to each category's data. Consequently, we found 4 cognitive factors of nuclear: 'trust in the authorities', 'utility of nuclear power generation', 'benefit for NPP siting areas', and 'risk perception about nuclear technology', regardless of the respondents' inhabiting areas, genders, and knowledge. In addition, when the respondents assess many perceptions of nuclear energy, respondents living in urban areas tend to regard 'trust in the authorities' as important, while respondents living in NPP siting areas tend to take into consideration of risk perception about nuclear technology'. (author)

  13. Isolation and Identification of mould inhabiting plant rizosphere in Gunung Mutis Natural Reserve, East Nusa Tenggara

    Directory of Open Access Journals (Sweden)

    MUHAMMAD ILYAS

    2006-07-01

    Full Text Available Indonesia as one of the megabiodiversity country has high biodiversity of plants, animals, and microbes. One of the microbe’s biodiversity is mould inhabiting plant rhizosphere. Research and exploration on mould inhabiting plant rhizosphere in Gunung Mutis Natural Reserve, NTT has never been conducted before. The objective of the study was to isolate and identify mould inhabiting several horticulture and reforestation plants rhizosphere in Gunung Mutis Natural Reserve, NTT. The mould isolation method was based on direct inoculation. The result showed that eight moulds genera with several species variants had been isolated. The isolated moulds genera were; Aspergillus, Cephalosporium, Cunninghamella, Eupenicillium, Fusarium (2 species, Paecilomyces, Penicillium (5 species, and Trichoderma.

  14. Assessment of immune surveillance among inhabitants of high natural background radiation areas in Ramsar-Iran

    International Nuclear Information System (INIS)

    Sileh, Sajad Borzouei; Monfared, Ali Shabestani; Mostafazade, Amrollah; Abedian, Said

    2010-01-01

    In this study by Multi-parameter flow cytometry, immunologic analyze is performed on peripheral blood, NK cells, most effective cells in innate immune and the proportion of TCD8/TCD4 cells that is effective in cellular immune system will be determined. Lysosomal-associated membrane protein-1 (LAMP-1 or CD107a) is used as a functional marker for the identification of natural killer cell activity. Immune surveillance and immune system role in tumoral defense in Ramsar inhabitants will be determined. Radiation dose rate in Talesh mahalle is very high and was many times greater than Chaparsar (another region in Ramsar). Immune surveillance and immune system role in tumoral defense in Talesh mahalle inhabitants will be compared to Chaparsar inhabitants. If this doesn't have significant difference, we should think about some other aspects such as free radical scavengers that will study later

  15. Significance of antifouling paint flakes to the distribution of dichlorodiphenyltrichloroethanes (DDTs) in estuarine sediment

    International Nuclear Information System (INIS)

    Wu, Chen-Chou; Bao, Lian-Jun; Tao, Shu; Zeng, Eddy Y.

    2016-01-01

    Recently published literature indicated that dichlorodiphenyltrichloroethane (DDT)-containing antifouling paint flakes were heterogeneously distributed within estuarine sediments. However, the significance of antifouling paint flakes in the fate and transport of DDT compounds and other organic pollutants in estuarine sediment is yet to be adequately addressed. To fill this knowledge gap, estuarine sediment and paint flakes from cabin and boat surfaces were collected from a fishery base in Guangdong Province of South China and analyzed for DDT compounds. Coarse fractioned samples collected from the vicinity of boat maintenance facilities contained appreciable amounts of colorful particles, which were identified as paint flakes by Fourier transform infrared spectroscopy. The highest concentrations of DDXs (sum of DDTs and its metabolites) occurred in the heavy-density (>1.7 g cm −3 ) fraction of coarse-size (200–2000 μm) sediments from near the boat maintenance facilities, suggesting the importance of paint flakes in the distribution pattern of “hot spots” in estuarine sediment. Moreover, the desorption rates of DDT compounds from paint flakes and the heavy-density fraction of coarse-size sediment were both extremely slow. Apparently, unevenly distributed paint flakes in sediment can artificially inflate the sorption capacity of heavy-density sediment for DDT compounds, and therefore can substantially change the environmental fate and behavior of hydrophobic organic chemicals in estuarine sediment. Finally, commonly used source diagnostic indices of DDT compounds were mostly grain-size and density dependent in sediment, as a result of the occurrence of paint flakes, which may strongly compromise the outcome of any source diagnostics efforts. - Highlights: • Concentrations of DDTs were elevated in coarse and high-density fractions. • The desorption rates of DDTs from coarse and high-density fraction were extreme slow. • DDTs-containing antifouling

  16. Water

    Science.gov (United States)

    ... environment and your health: Green living Sun Water Health effects of water pollution How to protect yourself from water pollution Air ... can hurt your health. Learn more about the health effects of polluted water. You can also learn more ... Source: U.S. Environmental Protection Agency Here are ...

  17. Traits of estuarine marsh plants affect wave dissipation

    Science.gov (United States)

    Schulte Ostermann, Tilla; Heuner, Maike; Bouma, Tjeerd

    2017-04-01

    Estuarine vegetation can attenuate hydrodynamic forces such as waves or flow velocities and therefore has an important role in natural tidal bank protection. This function depends on the degree of hydrodynamic forces, bank morphology and on plant traits of the dominant species. The traits vary between the species but also between different marsh sites. Biomass, stem density and biomechanical properties are crucial factors that influence the rate of wave dissipation. These properties illustrate the trade-offs a species is facing in such a dynamic habitat and highlight the ability of dominant species such as Bolboschoenus maritimus and Schoenoplectus tabernaemontani to protect the tidal bank. Along the Elbe estuary, traits of dominant marsh plant species were measured on different sites. The sites vary e.g. in their elevation, salt levels and inundation periods. To analyse the role that plant traits can play in wave dissipation, the structure of the vegetation as well as the composition was recorded. Biomechanical tests helped to understand the species traits regarding stem flexibility and to determine the effects of plant traits on wave dynamics and vice versa. On the conference, we will present how plant traits affect the wave dissipation on tidal marshes and why they vary.

  18. Land scale biogeography of arsenic biotransformation genes in estuarine wetland.

    Science.gov (United States)

    Zhang, Si-Yu; Su, Jian-Qiang; Sun, Guo-Xin; Yang, Yunfeng; Zhao, Yi; Ding, Junjun; Chen, Yong-Shan; Shen, Yu; Zhu, Guibing; Rensing, Christopher; Zhu, Yong-Guan

    2017-06-01

    As an analogue of phosphorus, arsenic (As) has a biogeochemical cycle coupled closely with other key elements on the Earth, such as iron, sulfate and phosphate. It has been documented that microbial genes associated with As biotransformation are widely present in As-rich environments. Nonetheless, their presence in natural environment with low As levels remains unclear. To address this issue, we investigated the abundance levels and diversities of aioA, arrA, arsC and arsM genes in estuarine sediments at low As levels across Southeastern China to uncover biogeographic patterns at a large spatial scale. Unexpectedly, genes involved in As biotransformation were characterized by high abundance and diversity. The functional microbial communities showed a significant decrease in similarity along the geographic distance, with higher turnover rates than taxonomic microbial communities based on the similarities of 16S rRNA genes. Further investigation with niche-based models showed that deterministic processes played primary roles in shaping both functional and taxonomic microbial communities. Temperature, pH, total nitrogen concentration, carbon/nitrogen ratio and ferric iron concentration rather than As content in these sediments were significantly linked to functional microbial communities, while sediment temperature and pH were linked to taxonomic microbial communities. We proposed several possible mechanisms to explain these results. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  19. Multiproxy evidence of Holocene climate variability from estuarine sediments, eastern North America

    Science.gov (United States)

    Cronin, T. M.; Thunell, R.; Dwyer, G.S.; Saenger, C.; Mann, M.E.; Vann, C.; Seal, R.R.

    2005-01-01

    We reconstructed paleoclimate patterns from oxygen and carbon isotope records from the fossil estuarine benthic foraminifera Elphidium and Mg/ Ca ratios from the ostracode Loxoconcha from sediment cores from Chesapeake Bay to examine the Holocene evolution of North Atlantic Oscillation (NAO)-type climate variability. Precipitation-driven river discharge and regional temperature variability are the primary influences on Chesapeake Bay salinity and water temperature, respectively. We first calibrated modern ??18 Owater to salinity and applied this relationship to calculate trends in paleosalinity from the ??18 Oforam, correcting for changes in water temperature estimated from ostracode Mg /Ca ratios. The results indicate a much drier early Holocene in which mean paleosalinity was ???28 ppt in the northern bay, falling ???25% to ???20 ppt during the late Holocene. Early Holocene Mg/Ca-derived temperatures varied in a relatively narrow range of 13?? to 16??C with a mean temperature of 14.2??C and excursions above 16??C; the late Holocene was on average cooler (mean temperature of 12.8??C). In addition to the large contrast between early and late Holocene regional climate conditions, multidecadal (20-40 years) salinity and temperature variability is an inherent part of the region's climate during both the early and late Holocene, including the Medieval Warm Period and Little Ice Age. These patterns are similar to those observed during the twentieth century caused by NAO-related processes. Comparison of the midlatitude Chesapeake Bay salinity record with tropical climate records of Intertropical Convergence Zone fluctuations inferred from the Cariaco Basin titanium record suggests an anticorrelation between precipitation in the two regions at both millennial and centennial timescales. Copyright 2005 by the American Geophysical Union.

  20. Metal enrichment in estuarine sediments proximal to acid sulfate soils as a novel palaeodrought proxy.

    Science.gov (United States)

    Job, Thomas; Penny, Dan; Hua, Quan

    2018-01-15

    Persistent drought over eastern Australia at the turn of the last millennium reduced stream flow in Australia's largest and most economically important drainage basin. Low water levels in the basin's terminal lakes triggered widespread pyrite oxidation, which altered surface water chemistry and released metals into the environment. The frequency of these events, and the links between drought and acid sulfate soil activation, are not known because the historical and instrumental records are short. Here, we present a Holocene-aged record of trace metal enrichment from Lake Albert-part of the terminal Lower Lakes system of the Murray-Darling Basin, Australia-that demonstrates the potential of trace elements mobilised during acidification events for palaeodrought reconstructions. Symptomatic metals were measured from a core of clayey sediment to form a multi-element assemblage that reveals acidification events in the geological past. Correlation with regional climate proxies suggests that climate forcing is significant in driving metal flux to estuarine sinks in acid sulfate soil rich landscapes, although the intensity of a drought is not the only variable responsible for acidification intensity. The constructed record indicates that regional climate moved from a generally humid climate phase with intermittent droughts, to a more arid climate at ~5.2ka which prevailed until ~1.7ka. Following conditions were relatively wet with low climatic variability through till European Settlement. Enrichment is observed coincident with both the 1982-83 drought and Millennium Drought, the latter of which reaching an intensity unsurpassed in the last ~4.8ka, likely a product of anthropogenic changes to the Lower Murray-Darling Basin system. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Isotopic Perspectives on the Foundation of Estuarine-Dependent Fish Biomass: Macrophytes Versus Microphytes

    Science.gov (United States)

    Hollander, D. J.; Malkin, E.; Murasko, S.; Peebles, E.

    2005-05-01

    Considerable trophic heterogeneity exists among the tidal rivers on Florida's west coast. Spring-fed estuaries tend to be oligotrophic, and urbanized surface-fed estuaries may be hypereutrophic. We compared wet- and dry-season primary producer sources of fish biomass among four rivers with differing trophic states. Dry-season 15-N distributions for vascular plants, microalgae and estuarine fish reflected river trophic status. Within rivers, 15-N values in vascular plants were regulated by extent of immersion in river water. All subaerial plants had 13-C values indicative of a common atmospheric CO2 source, whereas subaqueous microalgae had 13-C values that changed seasonally. In all rivers except the spring-fed Weeki Wachee, recycling of nitrogen within the sediments (i.e., denitrification) appeared to provide some of the nutrients used by benthic microalgae (BMA) during the dry season; the BMA were N-enriched relative to phytoplankton (POM) from the same waters. Most consumers appeared to be dependent on BMA during the dry season. Among Myakka and Peace River consumers, there was a pronounced shift from dry-season dependence on BMA to dependence on POM during the wet season. This contrasted with the oligotrophic Weeki Wachee River, where consumers remained dependent on BMA during both seasons. In the hypereutrophic Alafia River, only a partial shift to POM occurred, suggesting that the wet-season POM in the Alafia was less available to consumers. During the wet season, the chlorophyll maximum in the Alafia River shifts downstream to dredged locations that are prone to benthic hypoxia. We suggest that wet-season benthic hypoxia interferes with the transfer of sedimented POM biomass to higher trophic levels via surface-deposit-feeding macroinvertebrates.

  2. Effect of organic complexation on copper accumulation and toxicity to the estuarine red macroalga Ceramium tenuicorne: a test of the free ion activity model.

    Science.gov (United States)

    Ytreberg, Erik; Karlsson, Jenny; Hoppe, Sabina; Eklund, Britta; Ndungu, Kuria

    2011-04-01

    Current water quality criteria (WQC) regulations on copper toxicity to biota are still based on total dissolved (copper concentrations with a hardness modification for freshwaters. There are however ongoing efforts to incorporate metal speciation in WQC and toxicity regulations (such as the biotic ligand model-BLM) for copper and other metals. Here, we show that copper accumulation and growth inhibition of the Baltic macroalga Ceramium tenuicorne exposed to copper in artificial seawater at typical coastal and estuarine DOC concentrations (similar to 2-4 mg/L-C as fulvic acid) are better correlated to weakly complexed and total dissolved copper concentrations rather than the free copper concentration [Cu2+]. Our results using a combination of competitive ligand exchange-adsorptive cathodic stripping voltammetry (CLE-ACSV) measurements and model calculations (using visual MINTEQ incorporating the Stockholm Humic Model) show that copper accumulation in C. tenuicorne only correlates linearly well to [Cu2+] at relatively high [Cu2+] and in the absence of fulvic acid. Thus the FIAM fails to describe copper accumulation in C. tenuicorne at copper and DOC concentrations typical of most marine waters. These results seem to indicate that at ambient total dissolved copper concentration in coastal and estuarine waters, C. tenuicorne might be able to access a sizable fraction of organically complexed copper when free copper concentration to the cell membrane is diffusion limited.

  3. Development of a flow method for the determination of phosphate in estuarine and freshwaters-Comparison of flow cells in spectrophotometric sequential injection analysis

    Energy Technology Data Exchange (ETDEWEB)

    Mesquita, Raquel B.R. [CBQF/Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, R. Dr. Antonio Bernardino de Almeida, 4200-072 Porto (Portugal); Laboratory of Hydrobiology, Institute of Biomedical Sciences Abel Salazar (ICBAS) and Institute of Marine Research (CIIMAR), Universidade do Porto, Lg. Abel Salazar 2, 4099-003 Porto (Portugal); Ferreira, M. Teresa S.O.B. [CBQF/Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, R. Dr. Antonio Bernardino de Almeida, 4200-072 Porto (Portugal); Toth, Ildiko V. [REQUIMTE, Departamento de Quimica, Faculdade de Farmacia, Universidade de Porto, Rua Anibal Cunha, 164, 4050-047 Porto (Portugal); Bordalo, Adriano A. [Laboratory of Hydrobiology, Institute of Biomedical Sciences Abel Salazar (ICBAS) and Institute of Marine Research (CIIMAR), Universidade do Porto, Lg. Abel Salazar 2, 4099-003 Porto (Portugal); McKelvie, Ian D. [School of Chemistry, University of Melbourne, Victoria 3010 (Australia); Rangel, Antonio O.S.S., E-mail: aorangel@esb.ucp.pt [CBQF/Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, R. Dr. Antonio Bernardino de Almeida, 4200-072 Porto (Portugal)

    2011-09-02

    Highlights: {yields} Sequential injection determination of phosphate in estuarine and freshwaters. {yields} Alternative spectrophotometric flow cells are compared. {yields} Minimization of schlieren effect was assessed. {yields} Proposed method can cope with wide salinity ranges. {yields} Multi-reflective cell shows clear advantages. - Abstract: A sequential injection system with dual analytical line was developed and applied in the comparison of two different detection systems viz; a conventional spectrophotometer with a commercial flow cell, and a multi-reflective flow cell coupled with a photometric detector under the same experimental conditions. The study was based on the spectrophotometric determination of phosphate using the molybdenum-blue chemistry. The two alternative flow cells were compared in terms of their response to variation of sample salinity, susceptibility to interferences and to refractive index changes. The developed method was applied to the determination of phosphate in natural waters (estuarine, river, well and ground waters). The achieved detection limit (0.007 {mu}M PO{sub 4}{sup 3-}) is consistent with the requirement of the target water samples, and a wide quantification range (0.024-9.5 {mu}M) was achieved using both detection systems.

  4. Development of a flow method for the determination of phosphate in estuarine and freshwaters-Comparison of flow cells in spectrophotometric sequential injection analysis

    International Nuclear Information System (INIS)

    Mesquita, Raquel B.R.; Ferreira, M. Teresa S.O.B.; Toth, Ildiko V.; Bordalo, Adriano A.; McKelvie, Ian D.; Rangel, Antonio O.S.S.

    2011-01-01

    Highlights: → Sequential injection determination of phosphate in estuarine and freshwaters. → Alternative spectrophotometric flow cells are compared. → Minimization of schlieren effect was assessed. → Proposed method can cope with wide salinity ranges. → Multi-reflective cell shows clear advantages. - Abstract: A sequential injection system with dual analytical line was developed and applied in the comparison of two different detection systems viz; a conventional spectrophotometer with a commercial flow cell, and a multi-reflective flow cell coupled with a photometric detector under the same experimental conditions. The study was based on the spectrophotometric determination of phosphate using the molybdenum-blue chemistry. The two alternative flow cells were compared in terms of their response to variation of sample salinity, susceptibility to interferences and to refractive index changes. The developed method was applied to the determination of phosphate in natural waters (estuarine, river, well and ground waters). The achieved detection limit (0.007 μM PO 4 3- ) is consistent with the requirement of the target water samples, and a wide quantification range (0.024-9.5 μM) was achieved using both detection systems.

  5. Water

    Science.gov (United States)

    Leopold, Luna Bergere; Baldwin, Helene L.

    1962-01-01

    What do you use water for?If someone asked you this question you would probably think right away of water for drinking. Then you would think of water for bathing, brushing teeth, flushing the toilet. Your list would get longer as you thought of water for cooking, washing the dishes, running the garbage grinder. Water for lawn watering, for play pools, for swimming pools, for washing the car and the dog. Water for washing machines and for air conditioning. You can hardly do without water for fun and pleasure—water for swimming, boating, fishing, water-skiing, and skin diving. In school or the public library, you need water to wash your hands, or to have a drink. If your home or school bursts into flames, quantities of water are needed to put it out.In fact, life to Americans is unthinkable without large supplies of fresh, clean water. If you give the matter a little thought, you will realize that people in many countries, even in our own, may suffer from disease and dirt simply because their homes are not equipped with running water. Imagine your own town if for some reason - an explosion, perhaps - water service were cut off for a week or several weeks. You would have to drive or walk to a neighboring town and bring water back in pails. Certainly if people had to carry water themselves they might not be inclined to bathe very often; washing clothes would be a real chore.Nothing can live without water. The earth is covered by water over three-fourths of its surface - water as a liquid in rivers, lakes and oceans, and water as ice and snow on the tops of high mountains and in the polar regions. Only one-quarter of our bodies is bone and muscle; the other three-fourths is made of water. We need water to live, and so do plants and animals. People and animals can live a long time without food, but without water they die in a few days. Without water, everything would die, and the world would turn into a huge desert.

  6. North Inlet • Winyah Bay (NIW) National Estuarine Research Reserve Meteorological Data, North Inlet Estuary, Georgetown, South Carolina: 2000 • 2004.

    Data.gov (United States)

    Baruch Institute for Marine and Coastal Sciences, Univ of South Carolina — National Estuarine Research Reserve System The National Estuarine Research Reserve System was established by the Coastal Zone Management Act of 1972 (as amended) and...

  7. Water

    International Nuclear Information System (INIS)

    Chovanec, A.; Grath, J.; Kralik, M.; Vogel, W.

    2002-01-01

    An up-date overview of the situation of the Austrian waters is given by analyzing the status of the water quality (groundwater, surface waters) and water protection measures. Maps containing information of nitrate and atrazine in groundwaters (analyses at monitoring stations), nitrate contents and biological water quality of running waters are included. Finally, pollutants (nitrate, orthophosphate, ammonium, nitrite, atrazine etc.) trends in annual mean values and median values for the whole country for the years 1992-1999 are presented in tables. Figs. 5. (nevyjel)

  8. Water

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2010-08-01

    Full Text Available to explore desalination for future capacity. Water is essential to life: the human body is about 75 percent water, with up to 85 percent of brain cells liquid. Around 71 percent of the planet is covered in water, but 97,5 percent of it is salt water... risen to 90 percent, leaving only 10 percent for animals and plants. Yet 40 percent of the water used globally is for sanitation and other uses in buildings. The operation of buildings places a strain on raw water reserves, while wastewater and sewage...

  9. Using fish larvae as indicators of estuarine ecosystem condition in Rio de Janeiro State, Brazil

    Directory of Open Access Journals (Sweden)

    Regis Vinícius Souza Santos

    2015-11-01

    Full Text Available Estuaries enhance growth and maximize the survivorship of initial development stages of fish species, functioning as nursery grounds for many species. However, estuaries throughout the world host a wide variety of human activities, and fish communities can be severely impacted. Protection of aquatic biodiversity and proper management of these coastal systems require robust tools to assess habitat integrity and ecological quality status. Thus, the present study investigated the use of fish larvae as indicators of estuarine ecosystem condition in Brazil, testing the hypothesis that estuaries with different human impacts and environmental conditions carry distinct larval fish assemblages. For this, four estuaries were analysed with: similar environmental conditions (the same water mass surveyed, similar pool of species (the same geographical region and no seasonal influences (different periods analysed separately. Surveys were conducted in Macaé, São João, Bracuí and Perequê-Açu estuaries located in Rio de Janeiro State, Brazil. Sampling surveys were conducted every two months between May 2013 and March 2015. All samples were taken in the estuary middle region (salinity 15-25 during nightly ebb tides. At each estuary, ichthyoplankton subsurface tows were perfomed using a Bongo net. Water parameters were measured by a multiparameter probe and surface water samples collected for further analytical analyses. Fish larvae were identified and species were assigned into functional guilds. The water conditions were assessed based on water temperature, pH, chlorophyll a, dissolved oxygen and total particulate matter. Faecal coliforms, nutrient load (NO3, NO2, NH3, PO4, SiO3 and presence/absence of dams, dredging and mangroves were used as anthropogenic pressure descriptors. The species composition and ecological guilds of Macaé and Perequê-Açu differed significantly of São João and Bracuí, separating the impacted versus non-impacted estuaries

  10. The impact of park development on the lives of local inhabitants within Gros Morne National Park

    Science.gov (United States)

    Margot Herd; Paul. Heintzman

    2012-01-01

    The creation of a national park changes the local community's relationship to the land. In 1973, Parks Canada created Gros Morne National Park around existing communities and only relocated a small number of inhabitants to nearby communities. While park creation placed some restrictions on traditional activities, compromises were made to allow the continuation of...

  11. The Role of Social Influence on How Residence Hall Inhabitants Respond to Fire Alarms

    Science.gov (United States)

    Leytem, Michael; Stark, Emily

    2016-01-01

    College resident halls pose a threat for a catastrophic event in the case of fire, but little research has examined potential influences on students' responses to fire alarms, particularly the role of social influence in affecting their behaviors. In the current study, residence hall inhabitants reported their knowledge about fire safety, their…

  12. The Spaces and Places That Women Casual Academics (Often Fail To) Inhabit

    Science.gov (United States)

    Crimmins, Gail

    2016-01-01

    This paper discusses a research project that aims to address the binary/irony of the central physical and teaching space that women casual academics inhabit within Australian universities, against their lack of presence in the existing discourses around higher education. The invisibility of women casual academics within the discourses around…

  13. Disturbance and diversity of wood-inhabiting fungi: effects of canopy gaps and downed woody debris

    Science.gov (United States)

    Nicholas J. Brazee; Daniel L. Lindner; Anthony W. D' Amato; Shawn Fraver; Jodi A. Forrester; David J. Mladenoff

    2014-01-01

    Experimental canopy gap formation and additions of coarse woody debris (CWD) are techniques intended to mimic the disturbance regime and accelerate the development of northern hardwood forests. The effects of these techniques on biodiversity and ecosystem functioning were investigated by surveying the abundance and diversity of wood-inhabiting fungi in six treatments...

  14. The inhabited environment, infrastructure development and advanced urbanization in China’s Yangtze River Delta Region

    Science.gov (United States)

    Zhu, Xiaoqing; Gao, Weijun; Zhou, Nan; Kammen, Daniel M.; Wu, Yiqun; Zhang, Yao; Chen, Wei

    2016-12-01

    This paper analyzes the relationship among the inhabited environment, infrastructure development and environmental impacts in China’s heavily urbanized Yangtze River Delta region. Using primary human environment data for the period 2006-2014, we examine factors affecting the inhabited environment and infrastructure development: urban population, GDP, built-up area, energy consumption, waste emission, transportation, real estate and urban greenery. Then we empirically investigate the impact of advanced urbanization with consideration of cities’ differences. Results from this study show that the growth rate of the inhabited environment and infrastructure development is strongly influenced by regional development structure, functional orientations, traffic network and urban size and form. The effect of advanced urbanization is more significant in large and mid-size cities than huge and mega cities. Energy consumption, waste emission and real estate in large and mid-size cities developed at an unprecedented rate with the rapid increase of economy. However, urban development of huge and mega cities gradually tended to be saturated. The transition development in these cities improved the inhabited environment and ecological protection instead of the urban construction simply. To maintain a sustainable advanced urbanization process, policy implications included urban sprawl control polices, ecological development mechanisms and reforming the economic structure for huge and mega cities, and construct major cross-regional infrastructure, enhance the carrying capacity and improvement of energy efficiency and structure for large and mid-size cities.

  15. Mimogonellus dreybrodti sp. n., a new cave-inhabiting Osoriinae from Laos (Coleoptera: Staphylinidae).

    Science.gov (United States)

    Yin, Zi-Wei; Steiner, Helmut

    2017-10-17

    A new osoriine species, Mimogonellus dreybrodti Yin & Steiner, sp. n., collected from a cave in Houaphanh Province, Laos, is described and illustrated. This represents the third Mimogonellus species in Asia, and the first in the genus known to inhabit a cave environment.

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

    Science.gov (United States)

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

    2016-02-01

    Time series of environmental measurements are essential for detecting, measuring and understanding changes in the Earth system and its biological communities. Observational series have accumulated over the past 2-5 decades from measurements across the world's estuaries, bays, lagoons, inland seas and shelf waters influenced by runoff. We synthesize information contained in these time series to develop a global view of changes occurring in marine systems influenced by connectivity to land. Our review is organized around four themes: (i) human activities as drivers of change; (ii) variability of the climate system as a driver of change; (iii) successes, disappointments and challenges of managing change at the sea-land interface; and (iv) discoveries made from observations over time. Multidecadal time series reveal that many of the world's estuarine-coastal ecosystems are in a continuing state of change, and the pace of change is faster than we could have imagined a decade ago. Some have been transformed into novel ecosystems with habitats, biogeochemistry and biological communities outside the natural range of variability. Change takes many forms including linear and nonlinear trends, abrupt state changes and oscillations. The challenge of managing change is daunting in the coastal zone where diverse human pressures are concentrated and intersect with different responses to climate variability over land and over ocean basins. The pace of change in estuarine-coastal ecosystems will likely accelerate as the human population and economies continue to grow and as global climate change accelerates. Wise stewardship of the resources upon which we depend is critically dependent upon a continuing flow of information from observations to measure, understand and anticipate future changes along the world's coastlines. © 2015 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

  17. CONTRIBUTON OF DIFFERENT FOODSTUFFS TО THE INTERNAL EXPOSURE OF THE RURAL INHABITANTS OF THE BRYANSK REGION IN RUSSIA AFTER THE CHERNOBYL ACCIDENT

    Directory of Open Access Journals (Sweden)

    I. G. Travnikova

    2013-01-01

    Full Text Available In a large village Veprin of the Bryanskregion of Russiacontaminated with radionuclides as a result of the Chernobylaccident, 137Сs concentration in food products of agricultural produce and natural origin was regularly measured, local inhabitants were polled on the composition of their food ration, and 137Сs content in their bodies was at the same time measured. These results were used as the basis for calculation of annual effective doses of internal exposure to inhabitants and for reconstruction of the dose during the entire period after the accident. It will be divided into two stages: 1986–1996 yy and 1997–2012 yy. In this paper devoted to the first period (1986–1996, internal dose was reconstructed for 11 years after the accident, and the efficiency of countermeasures performed for reduction of the internal dose was assessed. The internal dose to inhabitants during the past 11 years after the accident was shown to be reduced almost twice, namely down to 35 mSv instead of the expected 70 mSv. The dose of external gamma radiation during the same time period is close to the obtained dose of internal exposure. The presence of peat and water-meadow soils in the vicinity of this village that are characterised by high transfer factors for radionuclides from soil to vegetation causes high contribution of internal exposure in the total dose of population exposure. Contribution of natural products to the internal dose grew from 6% in 1987 up to 25% in 1996. Individual content of 137Сs in the body of inhabitants reliably correlates with the consumption of milk in the early period after the accident and with consumption of forest mushrooms in the remote period.

  18. Water

    Science.gov (United States)

    ... Marion County, Indiana Salt Lake County, Utah Seattle-King County, Washington Tools and Training CLPPP CAP Healthy ... wish to use tap water for drinking or cooking, especially when the water has been off and ...

  19. Automatic fire-extinguishing system for inhabited pressurized compartments of manned spacecraft

    Science.gov (United States)

    Bolodian, Ivan; Melikhov, Anatoliy; Tanklevskiy, Leonid

    2017-06-01

    There is an innovational fire-extinguishing technology implemented via equipage of inhabited pressurized modules of the space station "Mir" and compartments of the Russian segment of International space station by automatic fire extinguishing systems in an orbital flight. Fire-safety in inhabited pressurized compartments of spacecraft (further - InPC SC) became one of the most dangerous factors during an orbital flight after a number of fire-hazardous situations occurred in different countries during preparation and execution of spaceflights [1,2]. High fire-risk in InPC of manned SC is determined by the following specific peculiarities of a arrangement and usage conditions of these items: - atmosphere of inhabited compartments is considerably enriched with oxygen - up to 25-40%; - there are many structural non-metal materials (here and after - materials) in order to lower the weight of InPC SC, most part of these materials is combustible under a given concentration of oxygen (here and after - Cox) in the atmosphere of InPC SC; - ventilation flow (here and after - Vvf) under normal operation of ventilation means in InPC SC considerably increases a possibility of fast fire-spread in InPC. - inhabited pressurized compartments of SC are filled with electrical equipment, which elements during failures even in low-current circuits became fire sources in oxygen-rich atmosphere; - indoor spaces of inhabited pressurized compartments of SC, as a rule, have complicated figuration with isolated for usage of local fire extinguishing zones with elements of electrical devices.

  20. Impact of the depth-to-width ratio of periodically stratified tidal channels on the estuarine circulation

    NARCIS (Netherlands)

    Schulz, E.; Schuttelaars, H.M.; Grawe, U.; Burchard, H.

    2015-01-01

    The dependency of the estuarine circulation on the depth-to-width ratio of a periodically, weakly stratified tidal estuary is systematically investigated here for the first time. Currents, salinity, and other properties are simulated by means of the General Estuarine Transport Model (GETM) in

  1. Trace elements and heavy metals in the Grand Bay National Estuarine Reserve in the northern Gulf of Mexico

    Science.gov (United States)

    The Grand Bay National Estuarine Research Reserve has the highest biotic diversity of habitats and offer a reserve of food resources and commercially significant species. Rapid human civilization has led to accumulation of heavy metals and trace elements in estuaries. The Grand Bay National Estuarin...

  2. Short-Term Nitrogen and Phosphorus Release during the Disturbance of Surface Sediments: A Case Study in an Urbanised Estuarine System (Gold Coast Broadwater, Australia

    Directory of Open Access Journals (Sweden)

    Ryan J.K. Dunn

    2017-04-01

    Full Text Available Understanding the effects of sediment disturbances on nutrient loadings is important for the management of estuarine settings. This study investigated the initial influence of sediment disturbance on water column nutrient concentrations in a shallow estuarine setting within the Gold Coast Broadwater, using a laboratory-based approach. Undisturbed sediment cores (200 mm Ø × 330 mm length, plexiglass were incubated before and after being subjected to a disturbance event, to investigate the effect on the immediate and subsequent short-term water column nutrient concentrations. Sediment NH4+bio and PO43−bio concentrations ranged from 150 to 478 and 1.50 to 8.56 nmol g−1 dry wt, respectively. Water column NH4+ concentrations underwent the greatest increase (>1000% or approx. 14 times greater immediately following disturbance, with mean effluxes increasing by >300%. Thereafter, water column NH4+ concentrations and efflux rates declined to near initial pre-disturbance concentrations. Water column NH4+ concentrations accounted for 0.58%–5.50% of the depth-integrated sediment NH4+bio concentration, indicating mobilization of the sediment bound exchangeable NH4+. The observed changes in PO43− concentrations and fluxes were much lower in comparison to those observed for N-species. Following disturbance, increases in the water column PO43− concentration accounted for 7.16%–8.22% depth-integrated sediment bioavailable PO43− at +1 and +2 hours, and 5.65% at +7 hours, respectively. These results provide important insight into the potential implications of disturbance events, such as vessel activities and dredging operations, within the case study region, providing information for potential management options and relevant water quality concerns.

  3. Quantifying site-specific physical heterogeneity within an estuarine seascape

    Science.gov (United States)

    Kennedy, Cristina G.; Mather, Martha E.; Smith, Joseph M.

    2017-01-01

    Quantifying physical heterogeneity is essential for meaningful ecological research and effective resource management. Spatial patterns of multiple, co-occurring physical features are rarely quantified across a seascape because of methodological challenges. Here, we identified approaches that measured total site-specific heterogeneity, an often overlooked aspect of estuarine ecosystems. Specifically, we examined 23 metrics that quantified four types of common physical features: (1) river and creek confluences, (2) bathymetric variation including underwater drop-offs, (3) land features such as islands/sandbars, and (4) major underwater channel networks. Our research at 40 sites throughout Plum Island Estuary (PIE) provided solutions to two problems. The first problem was that individual metrics that measured heterogeneity of a single physical feature showed different regional patterns. We solved this first problem by combining multiple metrics for a single feature using a within-physical feature cluster analysis. With this approach, we identified sites with four different types of confluences and three different types of underwater drop-offs. The second problem was that when multiple physical features co-occurred, new patterns of total site-specific heterogeneity were created across the seascape. This pattern of total heterogeneity has potential ecological relevance to structure-oriented predators. To address this second problem, we identified sites with similar types of total physical heterogeneity using an across-physical feature cluster analysis. Then, we calculated an additive heterogeneity index, which integrated all physical features at a site. Finally, we tested if site-specific additive heterogeneity index values differed for across-physical feature clusters. In PIE, the sites with the highest additive heterogeneity index values were clustered together and corresponded to sites where a fish predator, adult striped bass (Morone saxatilis), aggregated in a

  4. Sponge-rhodolith interactions in a subtropical estuarine system

    Science.gov (United States)

    Ávila, Enrique; Riosmena-Rodríguez, Rafael; Hinojosa-Arango, Gustavo

    2013-06-01

    The interactions between sponges and red macroalgae have been widely documented in tropical and subtropical environments worldwide, and many of them have been documented as mutualistic associations. Sponges, however, have also been frequently described as part of the associated fauna of rhodolith habitats (aggregations of free-living non-geniculated coralline macroalgae). Nonetheless, the types of interaction they establish as well as the role of sponges in these habitats remain unknown. In this study, the associations between sponges and rhodoliths were investigated in an estuarine ecosystem of the Mexican Pacific based on qualitative and quantitative data. A total of 13 sponge species were identified in five newly discovered rhodolith beds dominated by the non-geniculate coralline macroalga Lithophyllum margaritae. The sponge assemblages were strongly restricted to rhodolith habitats. The best predictor of sponge abundance (from 5.1 to 51.7 ind m-2) and species richness (from 2.6 to 6.1 sponge species m-2) was the rhodolith density rather than other population descriptors assessed (e.g., average size, branch density and sphericity). The identified sponges included a variety of forms: massive (46 %), encrusting (23 %), excavating (15 %), cushion-shape (8 %) and digitate (8 %). Moreover, more than 50 % of sponge species recorded (mainly massive and encrusting forms) were frequently found overgrowing and binding rhodoliths. Halichondria cf. semitubulosa and Mycale cecilia were the most common binding agents; these species bind an average of 3.1 and 6.6 rhodoliths per sponge individual, respectively. These findings reveal the importance of rhodoliths as habitat forming species, since these seaweed beds notably increased the substrate complexity in soft bottom environments. In addition, the relatively high abundance of sponges and their capability to bind rhodoliths suggest that these associated organisms could have an important contribution to rhodolith bed stability.

  5. Linking Species Traits to the Abiotic Template of Flowing Waters: Contrasting Eco physiologies Underlie Displacement of Zebra Mussels by Quagga Mussels in a Large River-Estuary

    Science.gov (United States)

    Casper, A. F.

    2005-05-01

    The St. Lawrence River-Estuary was the gateway of entry for dreissenids to North America and holds some of the oldest populations. The St. Lawrence also has four distinct physical-chemical water masses (a regional scale abiotic template) that both species inhabit. Despite their ecological similarities, quagga mussels are supplanting zebra mussels in much of their shared range. In order to try to better understand the changing distributions of these two species we compared glycogen, shell mass and tissue biomass in each of the water masses. This comparative physiological combined with experimental approaches (estuarine salinity experiments and reciprocal transplants) showed that while quagga mussels should dominate in most habitats, that abiotic/bioenergetic constraints in two regions (the Ottawa River plume and the freshwater-marine transition zone) might prevent them from dominating these locations. These findings are an example of how the interaction of landscape scale abiotic heterogeneity and a species-specific physiology can have strong impacts of distribution of biota large rivers.

  6. Amphibian, reptilian, and avian remains from the Fox Hills Formation (Maastrichtian): Shoreline and estuarine deposits of the Pierre Sea in south-central North Dakota

    Science.gov (United States)

    Hoganson, J.W.; Erickson, J.M.; Holland, F.D.

    2007-01-01

    Although vertebrate fossils, except for fish, are not common in the Maastrichtian Fox Hills Formation, amphibian, reptilian, and avian remains have been recovered at several localities in south-central North Dakota from shoreline facies of the retreating Pierre-Fox Hills seaway. This mixed fauna of aquatic, terrestrial, and marine taxa provides insight into the composition of coastal communities and habitats at the interface between the Hell Creek delta and the Western Interior Seaway. The delta-platform aquatic paleocommunity is represented by the efficient swimming salamanders Opistho- trition kayi and Lisserpeton bairdi, the carnivorous soft-shelled turtle "Aspideretes" sensu lato, the underwater piscivorous predator Champsosaurus laramiensis, and the large, predatory crocodile IBorealosuchus. Terrestrial areas were inhabited by the tortoise-like Basilemys and the predatory dinosaurs Tyrannosaurus and cf. Saurornit- holestes. Birds occupied niches in the warm-temperate to subtropical, forested delta platform and shoreline areas. These nonmarine taxa in the Fox Hills Formation indicate that the geographic range of these animals extended to shoreline areas of the Western Interior Seaway. The toxochelyid turtle Lophochelys and the ambush predators Mosasaurus dekayi and IPlioplatecarpus resided in the shallow marine and estuarine habitats. These taxa and marine fish taxa reported earlier indicate that normal marine conditions in south- central North Dakota persisted into the latest Late Cretaceous in comparison with coeval Hell Creek Formation sites more distal from the Western Interior Seaway. ?? 2007 The Geological Society of America. All rights reserved.

  7. Pollutant flows from a phosphogypsum disposal area to an estuarine environment: An insight from geochemical signatures

    Energy Technology Data Exchange (ETDEWEB)

    Pérez-López, Rafael, E-mail: rafael.perez@dgeo.uhu.es [Department of Geology, University of Huelva, Campus ‘El Carmen’, 21071 Huelva (Spain); Macías, Francisco; Cánovas, Carlos Ruiz [Department of Geology, University of Huelva, Campus ‘El Carmen’, 21071 Huelva (Spain); Sarmiento, Aguasanta Miguel [Department of Geodynamics and Palaeontology, University of Huelva, Campus ‘El Carmen’, 21071 Huelva (Spain); Pérez-Moreno, Silvia María [Department of Applied Physics, University of Huelva, Campus ‘El Carmen’, 21071 Huelva (Spain)

    2016-05-15

    Phosphogypsum wastes from phosphate fertilizer industries are stockpiled in stacks with high contamination potential. An assessment of the environmental impact, including the use of geochemical tracers such as rare earth elements (REE) and Cl/Br ratios, was carried out in the phosphogypsum stack located at the Estuary of Huelva (SW Spain). Inside the pile, highly polluted acid pore-waters flows up to the edge of the stack, emerging as small fluvial courses, known as edge outflows, which discharge directly into the estuary. The disposal area is divided into four zones; two unrestored zones with surface ponds of industrial process water and two a priori already-restored zones. However, an extensive sampling of edge outflows conducted in the perimeter of the four zones demonstrates the high potential of contamination of the whole stack, including those zones that were supposedly restored. These solutions are characterized by a pH of 1.9 and concentrations of 6100 mg/L for P, 1970 mg/L for S, 600 mg/L for F, 200 mg/L for NH{sub 4}{sup +}, 100 mg/L for Fe, 10–30 mg/L for Zn, As and U, and 1–10 mg/L for Cr, Cu and Cd. Preliminary restoration actions and those planned for the future prioritize removal of ponded process water and cover of the phosphogypsum with artificial topsoil. These actions presuppose that the ponded process water percolates through the porous medium towards the edge up to reach the estuary. However, geochemical tracers rule out this connection and point to an estuarine origin for these leachates, suggesting a possible tidal-induced leaching of the waste pile in depth. These findings would explain the ineffectiveness of preliminary restoration measures and should be considered for the development of new action plans. - Highlights: • Acidity and contaminants from phosphogypsum leaching are released to an estuary. • Already-restored zones act as a pollution source just as unrestored zones. • Cl/Br ratios and REE patterns were suitable to assess

  8. Anthropogenic forcing of estuarine hypoxic events in sub-tropical catchments: landscape drivers and biogeochemical processes.

    Science.gov (United States)

    Wong, Vanessa N L; Johnston, Scott G; Burton, Edward D; Bush, Richard T; Sullivan, Leigh A; Slavich, Peter G

    2011-11-15

    Episodic hypoxic events can occur following summer floods in sub-tropical estuaries of eastern Australia. These events can cause deoxygenation of waterways and extensive fish mortality. Here, we present a conceptual model that links key landscape drivers and biogeochemical processes which contribute to post-flood hypoxic events. The model provides a framework for examining the nature of anthropogenic forcing. Modification of estuarine floodplain surface hydrology through the construction of extensive drainage networks emerges as a major contributing factor to increasing the frequency, magnitude and duration of hypoxic events. Forcing occurs in two main ways. Firstly, artificial drainage of backswamp wetlands initiates drier conditions which cause a shift in vegetation assemblages from wetland-dominant species to dryland-dominant species. These species, which currently dominate the floodplain, are largely intolerant of inundation and provide abundant labile substrate for decomposition following flood events. Decomposition of this labile carbon pool consumes oxygen in the overlying floodwaters, and results in anoxic conditions and waters with excess deoxygenation potential (DOP). Carbon metabolism can be strongly coupled with microbially-mediated reduction of accumulated Fe and Mn oxides, phases which are common on these coastal floodplain landscapes. Secondly, artificial drainage enhances discharge rates during the flood recession phase. Drains transport deoxygenated high DOP floodwaters rapidly from backswamp wetlands to the main river channel to further consume oxygen. This process effectively displaces the natural carbon metabolism processes from floodplain wetlands to the main channel. Management options to reduce the impacts of post-flood hypoxia include i) remodifying drainage on the floodplain to promote wetter conditions, thereby shifting vegetation assemblages towards inundation-tolerant species, and ii) strategic retention of floodwaters in the backswamp

  9. Luminol-dependent chemiluminescence of hemocytes derived from marine and estuarine molluscs.

    Science.gov (United States)

    Kumazawa, N H; Morimoto, N; Okamoto, Y

    1993-04-01

    Hemocytes of two marine molluscs, Nerita albicilla (gastropod) and Mytilus edulis (bivalve), were stimulated in vitro with zymosan and live cells of Vibrio parahaemolyticus and Escherichia coli as determined by luminol-dependent chemiluminescence (CL). The CL response was enhanced in the presence of the respective molluscan plasma. Hemocytes of an estuarine gastropod, Clithon retropictus, showed low CL response to zymosan and V. parahaemolyticus, which was slightly enhanced in the presence of C. retropictus plasma. Hemocytes of an estuarine bivalve, Corbicula japonica, showed no CL response. CL response of hemocytes might be a useful tool to analyze defense mechanisms of estaurine molluscs.

  10. Striped Bass Spawning in Non-Estuarine Portions of the Savannah River

    Energy Technology Data Exchange (ETDEWEB)

    Martin, D.; Paller, M.

    2007-04-17

    Historically, the estuarine portions of the Savannah River have been considered to be the only portion of the river in which significant amounts of striped bass (Morone saxatilis) spawning normally occur. A reexamination of data from 1983 through 1985 shows a region between River Kilometers 144 and 253 where significant numbers of striped bass eggs and larvae occur with estimated total egg production near that currently produced in the estuarine reaches. It appears possible that there are two separate spawning populations of striped bass in the Savannah River.

  11. Changes in metal contamination levels in estuarine sediments around India – An assessment

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, P.; Ramteke, D.; Chakraborty, S.; Nath, B.N.

    among others. 14    Internal geochemical processes can lead to remobilization of trace metals and this phenomenon should be taken into account while comparing the results. The quantity of metals retained in sediments is also affected.... The intention of this study was to identify the estuaries with higher metal loading in the sediments. The ERL/ERM analysis suggests that the estuarine sediments around India are mainly in an “intermediate” to a “poor” state. Estuarine sediments of the Cochin...

  12. Accumulation and bioconcentration of polycyclic aromatic hydrocarbons in a nearshore estuarine environment near a Pensacola (Florida) creosote contamination site

    Science.gov (United States)

    Elder, J.F.; Dresler, P.V.

    1988-01-01

    Long-term accumulation of creosote wastes at a wood-preserving facility near Pensacola, Florida, has produced high levels of organic contamination of groundwaters near Pensacola Bay. Impacts of this contamination on the nearshore environment of the bay were examined by analysis of water, sediment and tissues of two mollusc species. One of the species (Thais haemastoma) was native to the study area. Individuals of the other test species (Crassostrea virginica) were placed in cages at the test sites for a 6-week period. Contamination at the nearshore estuarine sites was assessed by comparison to a control site in an uncontaminated area of the bay, as well as a small stream which forms a direct surface-water link between the creosote storage ponds and the bay. The study focused on polycyclic aromatic hydrocarbons (PAH), the primary components of creosote. Very little PAH in water or in the surface layer of estuarine sediments was detected, despite heavy pollution of the stream sediments. This is attributed to various degradation processes which attack the PAH compounds once they discharge into the estuary, and to the likelihood of intermittent and localised release of contaminants to the estuary. Examination of sediment cores and mollusc tissues, which provide a record integrated over time and space, revealed some accumulation of a few PAH, notably fluoranthene, pyrene, benzo(a)anthracene, chrysene and phenanthrene. In the sediments, the highest concentrations of these compounds appeared below the surface, within a depth range of 8-13 cm. Bioaccumulation of fluoranthene, pyrene and phenanthrene in both mollusc species was up to ten times greater at test sites than at the control site. This contrasts with naphthalene, the bioaccumulation of which was no greater at test sites than at the control site. These differences in bioaccumulation factors relate to structural chemistry of the compounds which control their solubility, bioavailability, susceptibility to degradation

  13. Estuarine circulation reversals and related rapid changes in winter near-bottom oxygen conditions in the Gulf of Finland, Baltic Sea

    Directory of Open Access Journals (Sweden)

    T. Liblik

    2013-10-01

    Full Text Available The reversal of estuarine circulation caused by southwesterly wind forcing may lead to vanishing of stratification and subsequently to oxygenation of deep layers during the winter in the Gulf of Finland. Six conductivity, temperature, depth (CTD+oxygen transects (130 km long, 10 stations were conducted along the thalweg from the western boundary to the central gulf (21 December 2011–8 May 2012. Two bottom-mounted ADCP were installed, one near the western border and the second in the central gulf. A CTD with a dissolved oxygen sensor was deployed close to the western ADCP. Periods of typical estuarine circulation were characterized by strong stratification, high salinity, hypoxic conditions and inflow to the gulf in the near-bottom layer. Two circulation reversals were observed: one in December–January and one in February. The first reversal event was well developed; it caused the disappearance of the stratification and an increase in the oxygen concentration from hypoxic values to 270 μmol L−1 (to 6 mL L−1 throughout the water column along the thalweg and lasted approximately 1.5 months. Shifts from estuarine circulation to reversed circulation and vice versa were both associated with strong longitudinal (east–west gulf currents (up to 40 cm s−1 in the deep layer. The change from oxygenated to hypoxic conditions in the western near-entrance area of the gulf occurred very rapidly, within less than a day, due to the intrusion of the hypoxic salt wedge from the NE Baltic Proper. In the eastern part of the gulf, good oxygen conditions caused by reversals remained for a few months.

  14. A comparison of the boating and swimming microbial water quality ...

    African Journals Online (AJOL)

    Calabar River Estuary is often used by both locals and tourists for boating and swimming making it necessary to assess the microbial recreational water quality of this water body. Five sampling stations were established – 3 in Calabar River and 2 in the Estuary. Calabar River stations were inshore while the estuarine ...

  15. Spatial variability of metal bioaccumulation in estuarine killifish (Fundulus heteroclitus) at the Callahan Mine Superfund site, Brooksville, ME

    Science.gov (United States)

    Buckman, Kate L.; Bugge, Deenie M.; Chen, Celia Y.

    2013-01-01

    The former Callahan Mine Site in Brooksville, ME is an open-pit, hardrock mine site in an intertidal system, providing a unique opportunity to evaluate how metal-enriched sediments and overlying water impact estuarine food webs. Cu, Zn, Cd, and Pb concentrations in sediment, whole water, and Atlantic killifish (Fundulus heteroclitus) were evaluated at sites in Goose Pond (the Callahan Mine Site) and at reference sites. The metal concentrations of sediment, water, and fish were spatially distinct and significantly higher at the Mine Site than in the reference estuary. Sediment concentrations were particularly elevated and were above probable effects levels (PEL) for all four metals adjacent to the tailings pile. Even in this well-mixed system, water metal concentrations were significantly elevated adjacent to the tailings pile and the concentrations of Cu and Zn were above ambient water quality criteria (AWQC) for chronic marine exposure. Neither organic matter in the sediment nor salinity or pH of the water explained the metal concentrations. Adjacent to the tailings pile, killifish body burdens were elevated and were significantly related to both sediment and aqueous concentrations. In conclusion, (1) the contaminated sediment and seepage from the tailings impoundment and waste rock pile 3 create a continual flux of metals into the water column, (2) the metals are bioavailable and are bioconcentrating as evident in the killifish tissue concentrations, and (3) Callahan Mine is directly affecting metal bioaccumulation in fauna residing in the Goose Pond estuary and, potentially, in Penobscot Bay via the ‘trophic nekton relay.’ PMID:24022459

  16. Effects of Tidal Action on Pollination and Reproductive Allocation in an Estuarine Emergent Wetland Plant–Sagittaria graminea (Alismataceae)

    Science.gov (United States)

    Zhang, Yanwen; Zhang, Lihui; Zhao, Xingnan; Huang, Shengjun; Zhao, Jimin

    2013-01-01

    In estuarine wetlands, the daily periodic tidal activity has a profound effect on plant growth and reproduction. We studied the effects of tidal action on pollination and reproductive allocation of Sagittaria graminea. Results showed that the species had very different reproductive allocation in tidal and non-tidal habitats. In the tidal area, seed production was only 9.7% of that in non-tidal habitat, however, plants produced more male flowers and nearly twice the corms compared to those in non-tidal habitat. An experiment showed that the time available for effective pollination determined the pollination rate and pollen deposition in the tidal area. A control experiment suggested that low pollen deposition from low visitation frequency is not the main cause of very low seed sets or seed production in this plant in tidal habitat. The negative effects of tides (water) on pollen germination may surpass the influence of low pollen deposition from low visitation frequency. The length of time from pollen deposition to flower being submerged by water affected pollen germination rate on stigmas; more than three hours is necessary to allow pollen germination and complete fertilization to eliminate the risk of pollen grains being washed away by tidal water. PMID:24244393

  17. [Analysis of good practices for inhabitant participation in the clinical management units of the Andalusian Health Service (Spain)].

    Science.gov (United States)

    Gómez Martínez, M Eugenia; Pastor Moreno, Guadalupe; Pérez Corral, Olivia; Iriarte de Los Santos, M Teresa; Mena Jiménez, Ángel Luis; Escudero Espinosa, M Cecilia; García Romera, Inmaculada; Blanco García, Martín Germán; Martín Barato, Amelia

    To discover good practices for inhabitant participation in the clinical management units (CMUs) of the Andalusian Health Service (AHS) (Spain) and to explore the reasons perceived by CMU and AHS professionals that may influence the presence and distribution of those good practices among the CMU. Study with mixed methodology carried out in Andalusia (Spain) in two phases (2013-2015). Firstly, an online survey was delivered to the Directors of the CMUs which had set up an inhabitant participation commission. In a second phase, a qualitative study was carried out through semi-structured interviews with professionals from the Andalusian Health Service with previous experience in inhabitant participation. A descriptive analysis of the quantitative information and a semantic content analysis of the qualitative information were carried out. 530 CMUs took part in the survey. The inhabitant participation practices more often implemented in the CMUs are those related to the informing and consultation levels. Twelve professionals were interviewed in the second phase. Other practices with higher inhabitant involvement and delegation are secondary. The barriers which were identified by professionals are related to the beliefs and attitudes of the inhabitants, the professionals, the health system and the environment. The main practices for inhabitant participation in the CMUs are related to the most basic levels of participation. The method and dynamics which facilitate inhabitant empowerment within the health system are not clearly recognised. Copyright © 2016 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  18. Abundance and distribution of enteric bacteria and viruses in coastal and estuarine sediments – a review.

    Directory of Open Access Journals (Sweden)

    Francis Hassard

    2016-11-01

    Full Text Available The long term survival of faecal indicator organisms (FIOs and human pathogenic microorganisms in sediments is important from a water quality, human health and ecological perspective. Typically, both bacteria and viruses strongly associate with particulate matter present in freshwater, estuarine and marine environments. This association tends to be stronger in finer textured sediments and is strongly influenced by the type and quantity of clay minerals and organic matter present. Binding to particle surfaces promotes the persistence of bacteria in the environment by offering physical and chemical protection from biotic and abiotic stresses. How bacterial and viral viability and pathogenicity is influenced by surface attachment requires further study. Typically, long-term association with surfaces including sediments induces bacteria to enter a viable-but-non-culturable (VBNC state. Inherent methodological challenges of quantifying VBNC bacteria may lead to the frequent under-reporting of their abundance in sediments. The implications of this in a quantitative risk assessment context remain unclear. Similarly, sediments can harbour significant amounts of enteric viruses, however, the factors regulating their persistence remains poorly understood. Quantification of viruses in sediment remains problematic due to our poor ability to recover intact viral particles from sediment surfaces (typically <10%, our inability to distinguish between infective and damaged (non-infective viral particles, aggregation of viral particles, and inhibition during qPCR. This suggests that the true viral titre in sediments may be being vastly underestimated. In turn, this is limiting our ability to understand the fate and transport of viruses in sediments. Model systems (e.g. human cell culture are also lacking for some key viruses, preventing our ability to evaluate the infectivity of viruses recovered from sediments (e.g. norovirus. The release of particle

  19. A Medical Consultation System to Support Health Care of Inhabitants through A Dialogue with Artificial Intelligence

    Science.gov (United States)

    Miyake, Hiroshi; Masuzawa, Hideaki

    A medical consultation system has been developed that encompasses knowledge of various specialties. The system is designed to be used by general practitioners, and inhabitants themselves. It has the characteristics of ; 1. The input task of complaints is simplified by use of multiple choice questionaires. 2. The system advices the person whether to seek medical help or not, and if so, the degree of urgency, and from what type of practitioner or specialist. 3. It supplies the doctor information regarding essential symptoms and possible diagnosis. 4. The system offer easy tools to make a medical consultation system to the specialists themselves. This system is intended as an answer to the common problem of uncertainty on the part of both inhabitants and doctors as to the area of medical speciality that applies to a given disease.

  20. Isolation and identification mould micoflora inhabiting plant leaf litter from Mount Lawu, Surakarta, Central Java

    Directory of Open Access Journals (Sweden)

    MUHAMMAD ILYAS

    2007-04-01

    Full Text Available A study on isolation and identification mould inhabiting plant leaf litter had been conducted. The objective of the study was to isolate and identify mould inhabiting plant leaf litter from Mount Lawu, Surakarta, Central Java. The mould isolation was based on washing and filtering with membrane isolation method. The result showed that 39 moulds generas with 55 species varians, one group identified in class level, and three groups of unidentified mould isolates had been isolated. Taxas distributions showed that there were endophyte and phytopatogen mould isolates had been isolated such as Fusarium, Pestalotiopsis, Phoma, and Coelomycetes. However, typical soil taxa and common saprobic fungi such as Aspergillus, Cunninghamella, Mucor, Paecilomyces, Penicillium, Rhizopus, and Trichoderma remain dominated the resulted isolates.

  1. Organochlorine pesticide level differences among female inhabitants from Veracruz, Puebla and Tabasco, Mexico.

    Science.gov (United States)

    Waliszewski, Stefan M; Caba, M; Saldarriaga-Noreña, H; Martínez, A J; Meza, E; Valencia Quintana, R; Zepeda, R

    2014-08-01

    Organochlorine pesticides have been used in Mexico in malaria control programs and against ectoparasites. The objective of this study was to compare the levels of organochlorine pesticides: HCB, α-β-γ-HCH, pp'-DDE, op'-DDT and pp'-DDT in adipose tissue of female inhabitants from three Mexican states: Veracruz, Puebla and Tabasco. Data analyses indicated higher β-HCH levels in Puebla inhabitants. When comparing the mean values of the pp'-DDE concentrations among the three states, no statistically significant differences were noted. A trend of increasing concentrations of op'-DDT from Veracruz to Puebla and Tabasco was observed. Significantly higher pp'-DDT concentrations in Veracruz as compared to Puebla and Tabasco were determined. Using factorial analysis of three age categories (>30, 31-50, <51) organochlorine pesticide concentrations increases with age of participants, indicating time of exposure as a principal factor of organochlorine pesticides accumulation in adipose tissue.

  2. Serological Survey of Hantavirus in Inhabitants from Tropical and Subtropical Areas of Brazil

    Directory of Open Access Journals (Sweden)

    Felipe Alves Morais

    2016-01-01

    Full Text Available Brazil has reported more than 1,600 cases of hantavirus cardiopulmonary syndrome (HPS since 1993, with a 39% rate of reported fatalities. Using a recombinant nucleocapsid protein of Araraquara virus, we performed ELISA to detect IgG antibodies against hantavirus in human sera. The aim of this study was to analyze hantavirus antibody levels in inhabitants from a tropical area (Amazon region in Rondônia state and a subtropical (Atlantic Rain Forest region in São Paulo state, Brazil. A total of 1,310 serum samples were obtained between 2003 and 2008 and tested by IgG-ELISA, and 82 samples (6.2%, of which 62 were from the tropical area (5.8% and 20 from the subtropical area (8.3%, tested positive. Higher levels of hantavirus antibody were observed in inhabitants of the populous subtropical areas compared with those from the tropical areas in Brazil.

  3. Encountering local inhabitants' perspectives in terms of authenticity: The example of rural tourism in southern Germany

    Directory of Open Access Journals (Sweden)

    T. Weidinger

    2015-05-01

    Full Text Available Effects of globalisation and various standardisation processes in everyday life are currently reflected through individuals’ quests for encountering authenticity. The paper interrogates in which particular ways local inhabitants evaluate rural localities with regard to authenticity by means of local architectural styles and filmic representations. Empirical findings from two qualitative studies carried out in rural Southern Germany are presented. The studies were comprised of qualitative interviews with local inhabitants and representatives in tourism, politics and heritage conservation together with a film analysis of a popular Heimat film shot in the Bavarian forest. Results reveal locals’ critique of modern architectural styles such as “Tuscan houses” as inauthentic, whereby a link between architecture and regional identity (“archidentity” cannot be established. However, the film analysis brings forth locals’ congruities between filmic representations and their lived spaces. In sum, locals’ perspectives on authentication processes can contribute to re-evaluate localities that are mainly shaped by idealised images for tourism purposes.

  4. Water

    OpenAIRE

    Hertie School of Governance

    2010-01-01

    All human life depends on water and air. The sustainable management of both is a major challenge for today's public policy makers. This issue of Schlossplatz³ taps the streams and flows of the current debate on the right water governance.

  5. Health-Associated Niche Inhabitants as Oral Probiotics: The Case of Streptococcus dentisani

    OpenAIRE

    L?pez-L?pez, Arantxa; Camelo-Castillo, Anny; Ferrer, Mar?a D.; Simon-Soro, ?urea; Mira, Alex

    2017-01-01

    Oral diseases, including dental caries and periodontitis, are among the most prevalent diseases worldwide and develop as a consequence of a microbial dysbiosis. Several bacterial strains are being tested as potential oral health-promoting organisms, but usually they are species isolated from niches other than the site where they must exert its probiotic action, typically from fecal samples. We hypothesize that oral inhabitants associated to health conditions will be more effective than tradit...

  6. How should work the thyroid monitoring for inhabitants of the destroyed area and its adjacent areas

    International Nuclear Information System (INIS)

    Nishizawa, Kunihide; Ito, Shigeki

    2011-01-01

    The general method of the exposure dose evaluation and the thyroid monitoring for it are explained and stressed. The vast area environmental contamination around the Fukushima Daiichi Nuclear Power Station accident brought about the anxiety of health risks for the inhabitants, especially probabilistic outbreak of cancer owing to radiation exposure. The report concludes that for the post traumatic stress disorder (PTSD) mental care and thyroid monitoring are necessary. (S. Ohno)

  7. Tidal variations in the Sundarbans Estuarine System, India

    Indian Academy of Sciences (India)

    At all stations, tidal water levels (every. 15 minutes), salinity, water and air temperatures (hourly) were measured over the six tidal cycles. We report the observed spatio-temporal variations of the tidal water level. The predominantly semi-diurnal tides were observed to amplify northwards along each estuary, with the highest ...

  8. Concentrations and ratios of Sr, Ba and Ca along an estuarine river to the Gulf of Mexico - implication for sea level rise effects on trace metal distribution

    Science.gov (United States)

    He, S.; Xu, Y. J.

    2015-11-01

    Strontium and barium to calcium ratios are often used as proxies for tracking animal movement across salinity gradients. As sea level rise continues, many estuarine rivers in the world face saltwater intrusion, which may cause changes in mobility and distribution of these metals upstream. Despite intensive research on metal adsorption and desorption in marine systems, knowledge of the spatiotemporal distribution of these elements along estuarine rivers is still limited. In this study, we conducted an intensive monitoring of Sr and Ba dynamics along an 88 km long estuary, the Calcasieu River in South Louisiana, USA, which has been strongly affected by saltwater intrusion. Over the period from May 2013 to August 2015, we collected monthly water samples and performed in-situ water quality measurements at six sites from the upstream to the river mouth, with a salinity range from 0.02 to 29.50 ppt. Water samples were analyzed for Sr, Ba, and Ca concentrations. In-situ measurements were made on salinity, pH, water temperature, dissolved oxygen concentration, and specific conductance. We found that the Sr and Ca concentrations and the Sr / Ca ratio all increased significantly with increasing salinity. The average Sr concentration at the site closest to the Gulf of Mexico (site 6) was 46.21 μmol L-1, which was about 130 times higher than that of the site furthest upstream (site 1, 0.35 μmol L-1). The average Ca concentration at site 6 was 8.19 mmol L-1, which was about 60 times higher than that of site 1 (0.13 mmol L-1). The average Sr / Ca ratio at site 6 (8.41 mmol mol-1) was about 3 times the average Sr / Ca ratio at site 1 (2.89 mmol mol-1). However, the spatial variation in Ba concentration was marginal, varying from 0.36 μmol L-1 at site 6 to 0.47 at site 5. The average Ba / Ca ratio at site 1 (4.82 mmol mol-1) was about 54 times the average Ba / Ca ratio at site 6 (0.09 mmol mol-1), showing a clear negative relation between the Ba / Ca ratio and increasing

  9. CORRELATION OF MIGRATORY ATTITUDES OF MAGADAN INHABITANTS AND FEATURES OF THEIR DEFENSIVE-COPING BEHAVIOUR

    Directory of Open Access Journals (Sweden)

    Snezhana A Kuznetsova

    2017-12-01

    Full Text Available The results of the empirical research of the correlation between the migratory attitudes of the inhabitants of Magadan and the features of their defensive-coping behavior are described in the article. Methods: the author’s scale of migratory attitudes of the personality, the scale of situational and personal anxiety by C.Spilberger, questionnaires “Life style index” (LSI, “Strategic Approach to Coping Scale” (SACS. The research with the participation of 68 Magadan inhabitants has shown that the inhabitants with the low level of personal anxiety, using regression as a defense mechanism, the coping forms: avoidance, indecisive actions and passive forms of coping behavior as a whole, have less expressed migratory attitudes. And on the contrary, the migratory attitudes are more likely to form in the respondents who are ready for active, resolute, constructive actions to change an unsatisfyingsituation, seek social support, take into account the needs, opinions and expectations of the immediate social environment. However, the correlations of migratory attitudes with the active forms of coping are not revealed. It means that the activity inherent in the subject does not necessarily imply a desire of migration, and can be implemented in the current region of residence.

  10. Non-linear behavior of public opinion on the issues regarding inhabitants' polls

    International Nuclear Information System (INIS)

    Ohnishi, Teruaki; Suganuma, Jyun-ichi

    2003-01-01

    The observed change of public attitude around the time of inhabitants' poll in Japan was compared with model calculation to investigate its non-linear behavior. Two inhabitants' polls regarding nuclear issues, the approval and disapproval of the construction of Maki nuclear station, and of the MOX fuel use at Kashiwazaki-Kariwa nuclear station, were considered together with the poll on the reconstruction of the tenth weir in Yoshino river carried out in Tokushima. By using a mathematical model such that the individual attitude is mainly subject to two factors of the information environment and the mutual communication between the public, it was found that the change and the unification of public attitude around the time of inhabitants' poll can be interpreted as a manifestation of self-organization resulted from the cooperative phenomenon of those two factors. Moreover, it was also found that the abrupt change of public attitude just before the poll can be interpreted as a result of positive feedback of the information environment formed by the various types of propaganda activities to the attitude change, though the extent of such non-linear effects differs from case to case. (author)

  11. Ernö Goldfinger and 2 Willow Road: inhabiting the modern utopia Hampstead, London

    Directory of Open Access Journals (Sweden)

    Catalina Mejía

    2010-12-01

    Full Text Available 1-3 Willow Road, houses built by Ernö Goldfinger facing Hampstead Heath in London, stand out as a paradigmatic example of Modernist British Architecture. Displacing traditional notions and ideals of a modernist house and of modernist inhabitation, what they ‘are’ goes somehow against to what they represent. Domesticity as well as concepts such as private and public, or exterior and interior are dislocated. Considered as one of the most distinguished manifestations of Modernity, in 2 Willow Road Modernism is suggested, but also disrupted by postmodern gestures. In a lifelong process that fills the space with collected objects, modernity is replaced by a more bourgeois environment: the atmosphere experienced in the interior is that of an inhabited collage closer to a nineteenth century dwelling. The heterogeneity of random order and arbitrary juxtapositions is, for this case, an aesthetic procedure that most likely legitimates Goldfinger’s beliefs and understanding of what life is. What 2 Willow Road actually testifies is about the romantic utopia of Modern inhabitation.

  12. Tidal effects on net ecosystem exchange of carbon in an estuarine wetland

    Science.gov (United States)

    H. Guo; A. Noormets; B. Zhao; J. Chen; G. Sun; Y. Gu; B. Li; J. Chen

    2009-01-01

    One year of continuous data from two eddy-flux towers established along an elevation gradient incoastal Shanghai was analyzed to evaluate the tidal effect on carbon flux (Fc) over an estuarine wetland.The measured wavelet spectra and cospectra of Fc and other environmental factors demonstrated thatthe...

  13. The Importance of Allochthonous Subsidies to an Estuarine Food Web along a Salinity Gradient

    Science.gov (United States)

    Estuarine food webs function within a heterogeneous mosaic and are supported by a mix of primary producers from both local and distant sources. Processes governing the exchange and consumption of organic matter (OM), however, are poorly understood. To study the contribution of ...

  14. Causes of extirpations in the Wadden Sea, an estuarine area in the Netherlands

    NARCIS (Netherlands)

    Wolff, WJ

    The various causes of extirpation of marine and estuarine species were investigated for the Dutch Wadden Sea to gain an impression of their relative importance. I obtained data from geological, archaeological, historical, and biological publications. At least 10 species of algae, 10 invertebrates,

  15. Fish community-based measures of estuarine ecological quality and pressure-impact relationships

    Science.gov (United States)

    Fonseca, Vanessa F.; Vasconcelos, Rita P.; Gamito, Rita; Pasquaud, Stéphanie; Gonçalves, Catarina I.; Costa, José L.; Costa, Maria J.; Cabral, Henrique N.

    2013-12-01

    Community-based responses of fish fauna to anthropogenic pressures have been extensively used to assess the ecological quality of estuarine ecosystems. Several methodologies have been developed recently combining metrics reflecting community structure and function. A fish community facing significant environmental disturbances will be characterized by a simplified structure, with lower diversity and complexity. However, estuaries are naturally dynamic ecosystems exposed to numerous human pressures, making it difficult to distinguish between natural and anthropogenic-induced changes to the biological community. In the present work, the variability of several fish metrics was assessed in relation to different pressures in estuarine sites. The response of a multimetric index (Estuarine Fish Assessment Index) was also analysed. Overall, fish metrics and the multimetric index signalled anthropogenic stress, particularly environmental chemical pollution. The fish assemblage associated with this type of pressure was characterized by lower species diversity, lower number of functional guilds, lower abundance of marine migrants and of piscivorous individuals, and higher abundance of estuarine resident species. A decreased ecological quality status, based on the EFAI, was also determined for sites associated with this pressure group. Ultimately, the definition of each pressure groups favoured a stressor-specific analysis, evidencing pressure patterns and accounting for multiple factors in a highly dynamic environment.

  16. Large-scale spatial patterns in estuaries: estuarine macrobenthic communities in the Schelde estuary, NW Europe

    NARCIS (Netherlands)

    Ysebaert, T.; Herman, P.M.J.; Meire, P.; Craeymeersch, J.A.M.; Verbeek, H.; Heip, C.H.R.

    2003-01-01

    Few macrobenthic studies have dealt simultaneously with the two major gradients in estuarine benthic habitats: the salinity gradient along the estuary (longitudinal) and the gradients from high intertidal to deep subtidal sites (vertical gradient). In this broad-scale study, a large data set (3112

  17. Are non-estuarine mangroves connected to coral reefs through fish migration? A mini-review

    NARCIS (Netherlands)

    Nagelkerken, I.

    2007-01-01

    Mangroves are an important fish habitat, but little is known of their nursery function and connectivity to other habitats such as coral reefs. Here, the present status of knowledge on connectivity between non-estuarine mangroves and coral reefs by postlarval coral reef fishes is reviewed. Only since

  18. Nitrogen distribution in a tropical urbanized estuarine system in northeastern Brazil.

    Science.gov (United States)

    Dos Santos, Celimarcos Bezerra; Silva, Maria Aparecida Macêdo; de Souza, Marcelo F Landim; da Silva, Daniela Mariano Lopes

    2018-01-08

    Nitrogen enters estuaries mostly through fluvial discharge and tide, although anthropogenic sources are known to influence the amount of this element in these aquatic ecosystems. Thus, the objective of this work was to verify which river (Cachoeira, Fundão, and/or Santana) exerts greater influence on the distribution of dissolved N forms (Dissolved Organic Nitrogen and Dissolved Inorganic Nitrogen = NH 3 /NH 4 + , NO 2 - , and NO 3 - ) along a tropical urbanized estuarine system in northeastern Brazil. The studies estuarine system lies with in urban municipality, and the upper portion of the Cachoeira river estuary receives the treated effluent from this municipality through a sewage treatment station and untreated effluents from nearby villages. The selected sampling stations were located near the outfall of the rivers in the estuaries to the treatment plant and the villages. Of all the nitrogen forms, dissolved organic nitrogen (DON) prevailed in the estuarine system, followed by nitrate (NO 3 - ) as the main inorganic form. The highest concentrations were recorded in the fluvial portion and upper estuary of Cachoeira river in the dry season. Based on the N concentrations found in the estuarine system, Cachoeira river has the greatest anthropogenic influence due to the amount of untreated effluents from the villages and treated effluents from the sewage treatment plant (STP) in the upper portion of the estuary.

  19. On the local dynamics of currents in the estuarine Marsdiep basin

    NARCIS (Netherlands)

    de Vries, J.J.

    2015-01-01

    The estuarine dynamics of the periodically-stratified Marsdiep basin, the westernmost part of the UNESCO world heritage site the Wadden Sea, are investigated through a broad range of observations and numerical model simulations. Spatial surveys and long-term point measurements of velocity, salinity,

  20. 77 FR 65533 - Proposed Information Collection; Comment Request; National Estuarine Research Reserve System...

    Science.gov (United States)

    2012-10-29

    ...) Science Collaborative was created in 2009 to put Reserve-based science to work for coastal communities... Collection; Comment Request; National Estuarine Research Reserve System Science Collaborative Evaluation... funded by the NERRS Science Collaborative are designed to bring the intended users of the science into...

  1. Modeling bioaccumulation and biomagnification of nonylphenol and its ethoxylates in estuarine-marine food chains

    NARCIS (Netherlands)

    Korsman, J.C.; Schipper, A.M.; Vos, de M.G.; Heuvel-Greve, van den M.J.; Vethaak, A.D.; Voogt, de Pim; Hendriks, A.J.

    2015-01-01

    There are several studies on bioaccumulation and biomagnification of nonylphenol (NP) and its ethoxylates (NPEOs), but their toxico-kinetic mechanisms remain unclear. In the present investigation, we explored the accumulation of NP and NPEOs in estuarine-marine food chains with a bioaccumulation

  2. Modeling bioaccumulation and biomagnification of nonylphenol and its ethoxylates in estuarine-marine food chains

    NARCIS (Netherlands)

    Korsman, J.C.; Schipper, A.M.; de Vos, M.G.; van den Heuvel-Greve, M.J.; Vethaak, A.D.; de Voogt, P.; Hendriks, A.J.

    2015-01-01

    There are several studies on bioaccumulation and biomagnification of nonylphenol (NP) and its ethoxylates (NPEOs), but their toxico-kinetic mechanisms remain unclear. In the present investigation, we explored the accumulation of NP and NPEOs in estuarine-marine food chains with a bioaccumulation

  3. Predicting the Spatial Distribution of Organic Contaminants in an Estuarine System using a Random Forest Approach

    Science.gov (United States)

    Modeling the magnitude and distribution of estuarine sediment contamination by pollutants of historic (e.g. PCB) and emerging concern (e.g., personal care products, PCP) is often limited by incomplete site knowledge and inadequate sediment contamination sampling. We tested a mode...

  4. Does estuarine health relate to catchment land-cover in the East ...

    African Journals Online (AJOL)

    Possible links between catchment and buffer zone land-cover class composition and the health of the East Kleinemonde Estuary were explored. There was a relationship between catchment land-cover and estuarine health within all assessed catchment delineations. Natural land-cover was determined to be the best ...

  5. Bivalve grazing, nutrient cycling and phytoplankton dynamics in an estuarine ecosystem

    NARCIS (Netherlands)

    Prins, T.C.

    1996-01-01


    This thesis has considered the impact of the suspension feeding bivalve Mytilusedulis on nutrient cycling and phytoplankton in an estuarine ecosystem. The research was started within the framework of an extensive research project with the

  6. St Lucia is one of the largest estuarine systems in Africa and forms ...

    African Journals Online (AJOL)

    denise

    Key words: catch and effort, management, recreational angling, socio-economics, St Lucia estuarine system ... South African Journal of Marine Science 24. 2002 .... Note that this species list is subject to misreporting by anglers, weights were often estimated by anglers and, in some cases, were not reported. Scientific name.

  7. Aggregation, sedimentation, dissolution and bioavailability of quantum dots in estuarine systems.

    Science.gov (United States)

    To understand their fate and transport in estuarine systems, the aggregation, sedimentation, and dissolution of CdSe quantum dots (QDs) in seawater were investigated. Hydrodynamic size increased from 40 to 60 nm to >1 mm within 1 h in seawater, and the aggregates were highly p...

  8. Estuarine fish and turtles as intermediate and paratenic hosts of Gnathostoma binucleatum in Nayarit, Mexico.

    Science.gov (United States)

    Guerrero, Cesar Alvarez; Alba-Hurtado, Fernando

    2007-12-01

    Human gnathostomosis is a severe public health problem in the State of Nayarit, Mexico. Between 1995 and 2005, the registration of human cases numbered 6,328, which makes it one of the largest focal points of the disease in the country. The present study determined the presence of natural hosts of Gnathostoma binucleatum larvae at the Laguna de Agua Brava in Nayarit, Mexico. A total of 5,450 fish and 247 turtles were sampled. Muscular tissue was ground and observed against the light using a 100-W lamp to identify advanced third-stage larvae. The estuarine species Cathorops fuerthii, Pomadasys macracanthus, Mugil curema, and Dormitator latifrons were found positive for presence of larvae, and annual prevalence was 4.8, 1.83, 2.16, and 4.0%, respectively. The species Oreochromys aureus and Chanos chanos were negative. The species of estuarine turtles Kinosternum integrum and Trachemys scripta were positive with annual prevalence of 79.1 and 52.5%, respectively. The criteria of identification of the Gnathostoma species were: mean number of nuclei in intestinal larval cells (2.3), larval morphometry with optic microscopy, larval morphometry with scanning electron microscopy, and number and sequence of ribosomal deoxyribonucleic acid of adult parasites obtained from experimental infection in dogs. The estuarine fish Pomadasys macracanthus and Mugil curema are reported as intermediate hosts for the first time and likewise the estuarine turtle Kinosternon integrum as a paratenic host.

  9. Aspects of the biology and ecology of the estuarine cirolanid isopod ...

    African Journals Online (AJOL)

    Trends in the distribution, population dynamics and reproductive biology of the estuarine cirolanid isopod, Cirolana fluviatilis, were investigated over a 12-month period in the warm–temperate Gamtoos River Estuary, by means of baited traps. Tolerance of adult isopods to combinations of salinity and temperature, and ...

  10. Water footprints of nations: water use by people as a function of their consumption pattern

    NARCIS (Netherlands)

    Hoekstra, Arjen Ysbert; Chapagain, Ashok

    2007-01-01

    The water footprint shows the extent of water use in relation to consumption of people. The water footprint of a country is defined as the volume of water needed for the production of the goods and services consumed by the inhabitants of the country. The internal water footprint is the volume of

  11. Water

    Directory of Open Access Journals (Sweden)

    E. Sanmuga Priya

    2017-05-01

    Full Text Available Phytoremediation through aquatic macrophytes treatment system (AMATS for the removal of pollutants and contaminants from various natural sources is a well established environmental protection technique. Water hyacinth (Eichhornia crassipes, a worst invasive aquatic weed has been utilised for various research activities over the last few decades. The biosorption capacity of the water hyacinth in minimising various contaminants present in the industrial wastewater is well studied. The present review quotes the literatures related to the biosorption capacity of the water hyacinth in reducing the concentration of dyestuffs, heavy metals and minimising certain other physiochemical parameters like TSS (total suspended solids, TDS (total dissolved solids, COD (chemical oxygen demand and BOD (biological oxygen demand in textile wastewater. Sorption kinetics through various models, factors influencing the biosorption capacity, and role of physical and chemical modifications in the water hyacinth are also discussed.

  12. Tide dependent seasonal changes in water quality and assimilative capacity of anthropogenically influenced Mormugao harbour water

    Digital Repository Service at National Institute of Oceanography (India)

    Shirodkar, P.V.; Deepthi, M.; Vethamony, P.; Mesquita, A.M.; Pradhan, U.K.; Babu, M.T.; Verlecar, X.N.; Haldankar, S.R.

    contaminated the estuarine and coastal waters2,3, at many locations along the Indian coat and affected their flora and fauna4-6. Zuari river in Goa, along the west coast of India, is one such river, where anthropogenic wastes are gradually contaminating its... : TIDE DEPENDENT SEASONAL CHANGES IN WATER QUALITY 315 quality and productivity. This has not been explored properly. In this study, an attempt has been made to understand how the dominant anthropogenic contaminants affect water quality...

  13. Are there general spatial patterns of mangrove structure and composition along estuarine salinity gradients in Todos os Santos Bay?

    Science.gov (United States)

    Costa, Patrícia; Dórea, Antônio; Mariano-Neto, Eduardo; Barros, Francisco

    2015-12-01

    Species distribution and structural patterns of mangrove fringe forests along three tropical estuaries were evaluated in northeast of Brazil. Interstitial water salinity, percentage of fine sediments and organic matter content were investigated as explanatory variables. In all estuaries (Jaguaripe, Paraguaçu and Subaé estuaries), it was observed similar distribution patterns of four mangrove species and these patterns were mostly related with interstitial water salinity. Rhizophora mangle and Avicennia schaueriana tended to dominate sites under greater marine influence (lower estuary), while Avicennia germinans and Laguncularia racemosa dominated areas under greater freshwater influence (upper estuary), although the latter showed a wider distribution over these tropical estuarine gradients. Organic matter best explained canopy height and mean height. At higher salinities, there was practically no correlation between organic matter and density, but at lower salinity, organic matter was related to decreases in abundances. The described patterns can be related to interspecific differences in salt tolerance and competitive abilities and they are likely to be found at other tropical Atlantic estuaries. Future studies should investigate anthropic influences and causal processes in order to further improve the design of monitoring and restoration projects.

  14. Early Life-Stage Responses of a Eurythemal Estuarine Fish, Mummichog (Fundulus hetereoclitus) to Fixed and Fluctuating Thermal Regimes

    Science.gov (United States)

    Shaifer, J.

    2016-02-01

    The mummichog (Fundulus hetereoclitus) is an intertidal spawning fish that ranges from the Gulf of St. Lawrence to northeastern Florida. A notoriously hardy species, adults can tolerate a wide range of temperature typical of inshore, estuarine waters. This experiment assessed how a wide range of constant and fluctuating temperatures affect the survival, development, and condition of embryos and young larvae. Captive adults were provided nightly with spawning substrates that were inspected each morning for fertilized eggs. Young ( 8 hr post-fertilization) embryos (N = 25 per population) were assigned to either one of a wide range of constant temperatures (8 to 34 °C) generated by a thermal gradient block (TGB), or to one of 10 daily oscillating temperature regimes that spanned the TGB's mid temperature (21 °C). Water was changed and populations inspected for mortalities and hatching at 12-hr intervals. Hatch dates and mortalities were recorded, and larvae were either anesthetized and measured for size by analyzing digital images, or evaluated for persistence in a food-free environment. Mummichog embryos withstood all but the coldest constant regimes and the entire range of fluctuating ones although age at hatching varied substantially within and among experimental populations. Embryos incubated at warmer temperatures hatched out earlier and at somewhat smaller sizes than those experiencing cooler temperatures. Temperatures experienced by embryos had an inverse effect on persistence of larvae relying on yolk nutrition alone. Mummichog exhibited an especially plastic response to thermal challenges which reflects the highly variable nursery habitat used by this species.

  15. Recruitment of flatfish species to an estuarine nursery habitat (Lima estuary, NW Iberian Peninsula)

    Science.gov (United States)

    Ramos, Sandra; Ré, Pedro; Bordalo, Adriano A.

    2010-11-01

    One of the present concerns of fish biologists involves defining and identifying nursery habitats in the context of conservation and resource management strategies. Fish nursery studies usually report upon nursery occupation during the latter juvenile stages, despite the fact that recruitment to nurseries can start early in life, during the larval phase. Here we investigated the use of a temperate estuarine nursery area, the Lima estuary (NW Portugal), by initial development stages of flatfish species before and after metamorphosis, integrating the larval and juvenile phases. The Lima estuarine flatfish community comprised twelve taxa, seven of which were present as pelagic larvae, six as juveniles and three as adults. There was a general trend of increasing spring-summer abundance of both larvae and juveniles, followed by a sharp winter decrease, mainly of larval flatfishes. The Lima estuary was used by Solea senegalensis, Platichthys flesus and Solea solea as a nursery area, with direct settlement for the two first species. In contrast, indirect settlement was suggested for S. solea, with metamorphosis occurring outside the estuarine area. Estuarine recruitment of S. senegalensis varied between years, with young larvae occurring in the estuary throughout a prolonged period that lasted 6-9 months, corroborating the protracted spawning season. P. flesus, the second most abundant species, exhibited a typical spring estuarine recruitment, without inter-annual variations. Developed larvae arrived in the estuary during spring, whereas the 0-group juveniles emerged in the following summer period. The present study contributes new insight to our understanding of the economically important S. senegalensis, and highlights the importance of integrating the planktonic larval phase into traditional flatfish nursery studies.

  16. Climate change, precipitation and impacts on an estuarine refuge from disease.

    Science.gov (United States)

    Levinton, Jeffrey; Doall, Michael; Ralston, David; Starke, Adam; Allam, Bassem

    2011-04-28

    Oysters play important roles in estuarine ecosystems but have suffered recently due to overfishing, pollution, and habitat loss. A tradeoff between growth rate and disease prevalence as a function of salinity makes the estuarine salinity transition of special concern for oyster survival and restoration. Estuarine salinity varies with discharge, so increases or decreases in precipitation with climate change may shift regions of low salinity and disease refuge away from optimal oyster bottom habitat, negatively impacting reproduction and survival. Temperature is an additional factor for oyster survival, and recent temperature increases have increased vulnerability to disease in higher salinity regions. We examined growth, reproduction, and survival of oysters in the New York Harbor-Hudson River region, focusing on a low-salinity refuge in the estuary. Observations were during two years when rainfall was above average and comparable to projected future increases in precipitation in the region and a past period of about 15 years with high precipitation. We found a clear tradeoff between oyster growth and vulnerability to disease. Oysters survived well when exposed to intermediate salinities during two summers (2008, 2010) with moderate discharge conditions. However, increased precipitation and discharge in 2009 reduced salinities in the region with suitable benthic habitat, greatly increasing oyster mortality. To evaluate the estuarine conditions over longer periods, we applied a numerical model of the Hudson to simulate salinities over the past century. Model results suggest that much of the region with suitable benthic habitat that historically had been a low salinity refuge region may be vulnerable to higher mortality under projected increases in precipitation and discharge. Predicted increases in precipitation in the northeastern United States due to climate change may lower salinities past important thresholds for oyster survival in estuarine regions with

  17. Significance of antifouling paint flakes to the distribution of dichlorodiphenyltrichloroethanes (DDTs) in estuarine sediment.

    Science.gov (United States)

    Wu, Chen-Chou; Bao, Lian-Jun; Tao, Shu; Zeng, Eddy Y

    2016-03-01

    Recently published literature indicated that dichlorodiphenyltrichloroethane (DDT)-containing antifouling paint flakes were heterogeneously distributed within estuarine sediments. However, the significance of antifouling paint flakes in the fate and transport of DDT compounds and other organic pollutants in estuarine sediment is yet to be adequately addressed. To fill this knowledge gap, estuarine sediment and paint flakes from cabin and boat surfaces were collected from a fishery base in Guangdong Province of South China and analyzed for DDT compounds. Coarse fractioned samples collected from the vicinity of boat maintenance facilities contained appreciable amounts of colorful particles, which were identified as paint flakes by Fourier transform infrared spectroscopy. The highest concentrations of DDXs (sum of DDTs and its metabolites) occurred in the heavy-density (>1.7 g cm(-3)) fraction of coarse-size (200-2000 μm) sediments from near the boat maintenance facilities, suggesting the importance of paint flakes in the distribution pattern of "hot spots" in estuarine sediment. Moreover, the desorption rates of DDT compounds from paint flakes and the heavy-density fraction of coarse-size sediment were both extremely slow. Apparently, unevenly distributed paint flakes in sediment can artificially inflate the sorption capacity of heavy-density sediment for DDT compounds, and therefore can substantially change the environmental fate and behavior of hydrophobic organic chemicals in estuarine sediment. Finally, commonly used source diagnostic indices of DDT compounds were mostly grain-size and density dependent in sediment, as a result of the occurrence of paint flakes, which may strongly compromise the outcome of any source diagnostics efforts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Nursery use patterns of commercially important marine fish species in estuarine systems along the Portuguese coast

    Science.gov (United States)

    Vasconcelos, R. P.; Reis-Santos, P.; Maia, A.; Fonseca, V.; França, S.; Wouters, N.; Costa, M. J.; Cabral, H. N.

    2010-03-01

    Analysing the estuarine use patterns of juveniles of marine migrant fish species is vital for identifying important sites for juveniles as well as the basic environmental features that characterize these sites for different species. This is a key aspect towards understanding nursery function. Various estuarine systems along the Portuguese coast (Minho, Douro, Ria de Aveiro, Mondego, Tejo, Sado, Mira, Ria Formosa and Guadiana) were sampled during Spring and Summer 2005 and 2006. Juveniles of commercially important marine fish species Solea solea, Solea senegalensis, Platichthys flesus, Diplodus vulgaris and Dicentrarchus labrax, predominantly 0-group individuals, were amongst the most abundant species and had distinct patterns of estuarine use as well as conspicuous associations with several environmental features. Juvenile occurrence and density varied amongst estuaries and sites within them, and differed with species. Sites with consistently high juvenile densities were identified as important juvenile sites (i.e. putative nursery grounds). Through generalized linear models (GLM), intra-estuarine variation in occurrence and density of each of the individual species was largely explained by environmental variables (temperature; salinity; depth; percentage of mud in the sediment; presence of seagrass; importance of intertidal areas; relative distance to estuary mouth; macrozoobenthos densities; and latitude). Decisive environmental factors defining important sites for juveniles varied depending on the system as a result of different environmental gradients, though there were common dominant features for each species regardless of the estuary considered. Analysed environmental variables in the GLM also accounted for inter-estuarine variation in species' occurrence and density. In several estuaries, the identified important juvenile sites were used by many of these species simultaneously and may be of increased value to both management and conservation. Overall, the

  19. Three-dimensional semi-idealized model for estuarine turbidity maxima in tidally dominated estuaries

    Science.gov (United States)

    Kumar, Mohit; Schuttelaars, Henk M.; Roos, Pieter C.

    2017-05-01

    We develop a three-dimensional idealized model that is specifically aimed at gaining insight in the physical mechanisms resulting in the formation of estuarine turbidity maxima in tidally dominated estuaries. First, the three-dimensional equations for water motion and suspended sediment concentration together with the so-called morphodynamic equilibrium condition, are scaled. Next, surface elevation, velocity and sediment concentration are expanded in a small parameter ɛ =AbarM2 / H , where AbarM2 is the mean amplitude of the M2 tide and H is the mean water depth at the seaward side. This results in a system of equations at each order in this small parameter. This ordering allows solving for the vertical structure of the velocity and suspended sediment concentration, independently of the horizontal dimension. After obtaining these vertical structures, the horizontal dependencies of the physical variables follow from solving a two-dimensional elliptic partial differential equation for the surface elevation. The availability of fine sediments in the estuary follows from a two-dimensional elliptic partial differential equation which results from requiring the system to be in morphodynamic equilibrium, and prescribing the total amount of easily erodible sediments available in the estuary. These elliptic equations for the surface elevation and sediment availability are solved numerically using the finite element method with cubic polynomials as basis functions. As a first application, the model is applied to the Ems estuary using a simplified geometry and bathymetric profiles characteristic for the years 1980 and 2005. The availability of fine sediments and location of maximum concentration are investigated for different lateral depth profiles. In the first experiment, a uniform lateral depth is considered. In this case, both the sediment availability and suspended sediment concentration are, as expected, uniform in the lateral direction. In 1980, the sediment is

  20. Evolution of cadmium tolerance and associated costs in a Gammarus fossarum population inhabiting a low-level contaminated stream.

    Science.gov (United States)

    Vigneron, A; Geffard, O; Coquery, M; François, A; Quéau, H; Chaumot, A

    2015-08-01

    Deciphering evolutionary processes occurring within long-term contaminated wild populations is essential for the ecological risk assessment of persistent chemical contaminations. Using field populations of Gammarus, a commonly-used genus in aquatic ecotoxicology, the present study sought to gain insights into the extent to which long-term exposure to metals in the field could effectively lead to shifts in toxicological sensitivities. For this, we identified a Gammarus population inhabiting a stream contaminated by cadmium (Cd). We compared the Cd-exposure and Cd-sensitivity of this population to those of five reference populations. Active biomonitoring determined in different years and seasons that significant levels of Cd were bioavailable in the contaminated site. Laboratory sensitivity tests under common garden conditions established that this long-term field exposure led to the development of a moderate Cd tolerance, which was maintained after a 3-week acclimatization in the laboratory, and transmitted to offspring produced under clean conditions. The potential physiological costs of tolerance were assessed by means of feeding rate measurements (in the laboratory and in situ). They revealed that, unlike for reference populations, the feeding activity of organisms from the tolerant population was greatly decreased when they were maintained under laboratory conditions, potentially indicating a high population vulnerability to environmental perturbations. Because dissolved Cd concentrations in water from the contaminated site were low (averaging 0.045 µg L(-1)) and below the current European environmental quality standard for Cd for inland surface waters (fixed at 0.08 µg L(-1) in soft water environments), this case study sheds light onto the extent to which current environmental quality standards are protective against potential adverse outcomes of adaptive and micro-evolutionary processes occurring in contaminated environments.