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Evaluation of physical, chemical and microbiological parameters of water quality in the Harris Neck estuarine marshes along the Georgia coast Full text
2011
Markand, Shanu | Bachoon, Dave S. | Gentit, Lisa | Sherchan, Samendra | Gates, Keith
Analysis of the physical, chemical and biological parameters assessing water quality in Harris Neck estuary indicated that the average dissolved oxygen level was 8.6mg/L, it maintained moderate levels of total dissolved nitrogen (2.7–4.6mg/L) and total dissolved phosphorous (<0.05mg/L), chlorophyll a was above 5.0μg/L and it is contaminated with low levels of fecal bacteria. Bifidobacterium adolescentis, a putative marker of human fecal pollution, was detected once at stations 3 and 5. Overall the Harris Neck water quality analyses indicated a relatively pristine and a healthy functioning marine environment.
Show more [+] Less [-]Evaluation of sewage source and fate on southeast Florida coastal reefs Full text
2011
Carrie Futch, J. | Griffin, Dale W. | Banks, Kenneth | Lipp, Erin K.
Water, sponge and coral samples were collected from stations impacted by a variety of pollution sources and screened for human enteric viruses as conservative markers for human sewage. While human enteroviruses and adenoviruses were not detected, noroviruses (NoV; human genogroups I and II) were detected in 31% of samples (especially in sponge tissue). Stations near inlets were the only ones to show multiple sample types positive for NoV. Fecal indicator bacteria and enteric viruses were further evaluated at multiple inlet stations on an outgoing tide. Greatest indicator concentrations and highest prevalence of viruses were found at the mouth of the inlet and offshore in the inlet plume. Results suggest that inlets moving large volumes of water into the coastal zone with tides may be an important source of fecal contaminants. Efforts to reduce run-off or unintended release of water into the Intracoastal Waterway may lower contaminants entering sensitive coastal areas.
Show more [+] Less [-]Phytoplankton distribution and productivity in a highly turbid, tropical coastal system (Bach Dang Estuary, Vietnam) Full text
2011
Rochelle-Newall, E.J. | Chu, V.T. | Pringault, O. | Amouroux, D. | Arfi, R. | Bettarel, Y. | Bouvier, T. | Bouvier, C. | Got, P. | Nguyen, T.M.H. | Mari, X. | Navarro, P. | Duong, T.N. | Cao, T.T.T. | Pham, T.T. | Ouillon, S. | Torréton, J.-P.
Phytoplankton distribution and productivity in a highly turbid, tropical coastal system (Bach Dang Estuary, Vietnam) Full text
2011
Rochelle-Newall, E.J. | Chu, V.T. | Pringault, O. | Amouroux, D. | Arfi, R. | Bettarel, Y. | Bouvier, T. | Bouvier, C. | Got, P. | Nguyen, T.M.H. | Mari, X. | Navarro, P. | Duong, T.N. | Cao, T.T.T. | Pham, T.T. | Ouillon, S. | Torréton, J.-P.
Phytoplankton diversity, primary and bacterial production, nutrients and metallic contaminants were measured during the wet season (July) and dry season (March) in the Bach Dang Estuary, a sub-estuary of the Red River system, Northern Vietnam. Using canonical correspondence analysis we show that phytoplankton community structure is potentially influenced by both organometallic species (Hg and Sn) and inorganic metal (Hg) concentrations. During March, dissolved methylmercury and inorganic mercury were important factors for determining phytoplankton community composition at most of the stations. In contrast, during July, low salinity phytoplankton community composition was associated with particulate methylmercury concentrations, whereas phytoplankton community composition in the higher salinity stations was more related to dissolved inorganic mercury and dissolved mono and tributyltin concentrations. These results highlight the importance of taking into account factors other than light and nutrients, such as eco-toxic heavy metals, in understanding phytoplankton diversity and activity in estuarine ecosystems.
Show more [+] Less [-]Phytoplankton distribution and productivity in a highly turbid, tropical coastal system (Bach Dang Estuary, Vietnam) Full text
2011
Rochelle-Newall, E.J. | Chu, V.T. | Pringault, O. | Amouroux, David | Arfi, Robert | Bettarel, Y. | Bouvier, T. | Bouvier, C. | Got, P. | Nguyen, T.M.H. | Mari, Xavier | Navarro, Pablo | Duong, T.N. | Cao, T.T.T. | Pham, T.T. | Ouillon, S. | Torréton, J.-P. | Biogéochimie et écologie des milieux continentaux (Bioemco) ; École normale supérieure - Paris (ENS-PSL) ; Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS) | Institute of Marine Environment and Resources, Haiphong (IMER) ; VAST | Ecosystèmes lagunaires : organisation biologique et fonctionnement (ECOLAG) ; Université Montpellier 2 - Sciences et Techniques (UM2)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS) | Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM) ; Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS) | Institut pluridisciplinaire de recherche sur l'environnement et les matériaux (IPREM) ; Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS) | Echanges Côte-Large (ECOLA) ; Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS) | This work was financed by the EC2CO project 'HAIPHONG', and Grants from the French IRD, CNRS, Groupement De Recherche (GDR) 2476 Réseaux Trophiques Pélagiques, and the Vietnam Academy of Science and Technology (VAST).
International audience | Phytoplankton diversity, primary and bacterial production, nutrients and metallic contaminants were measured during the wet season (July) and dry season (March) in the Bach Dang Estuary, a sub-estuary of the Red River system, Northern Vietnam. Using canonical correspondence analysis we show that phytoplankton community structure is potentially influenced by both organometallic species (Hg and Sn) and inorganic metal (Hg) concentrations. During March, dissolved methylmercury and inorganic mercury were important factors for determining phytoplankton community composition at most of the stations. In contrast, during July, low salinity phytoplankton community composition was associated with particulate methylmercury concentrations, whereas phytoplankton community composition in the higher salinity stations was more related to dissolved inorganic mercury and dissolved mono and tributyltin concentrations. These results highlight the importance of taking into account factors other than light and nutrients, such as eco-toxic heavy metals, in understanding phytoplankton diversity and activity in estuarine ecosystems.
Show more [+] Less [-]Phytoplankton distribution and productivity in a highly turbid, tropical coastal system (Bach Dang Estuary, Vietnam) Full text
2011
Rochelle-Newall, E.J. | Chu, V.T. | Pringault, O. | Amouroux, David | Arfi, Robert | Bettarel, Y. | Bouvier, T. | Bouvier, C. | Got, P. | Nguyen, T.M.H. | Mari, Xavier | Navarro, Pablo | Duong, T.N. | Cao, T.T.T. | Pham, T.T. | Ouillon, S. | Torréton, J.-P. | Biogéochimie et écologie des milieux continentaux (Bioemco) ; École normale supérieure - Paris (ENS-PSL) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS) | Institute of Marine Environment and Resources, Haiphong (IMER) ; VAST | Ecosystèmes lagunaires : organisation biologique et fonctionnement (ECOLAG) ; Université Montpellier 2 - Sciences et Techniques (UM2)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS) | Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM) ; Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | Institut pluridisciplinaire de recherche sur l'environnement et les matériaux (IPREM) ; Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS) | Echanges Côte-Large (ECOLA) ; Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS) | This work was financed by the EC2CO project 'HAIPHONG', and Grants from the French IRD, CNRS, Groupement De Recherche (GDR) 2476 Réseaux Trophiques Pélagiques, and the Vietnam Academy of Science and Technology (VAST).
International audience | Phytoplankton diversity, primary and bacterial production, nutrients and metallic contaminants were measured during the wet season (July) and dry season (March) in the Bach Dang Estuary, a sub-estuary of the Red River system, Northern Vietnam. Using canonical correspondence analysis we show that phytoplankton community structure is potentially influenced by both organometallic species (Hg and Sn) and inorganic metal (Hg) concentrations. During March, dissolved methylmercury and inorganic mercury were important factors for determining phytoplankton community composition at most of the stations. In contrast, during July, low salinity phytoplankton community composition was associated with particulate methylmercury concentrations, whereas phytoplankton community composition in the higher salinity stations was more related to dissolved inorganic mercury and dissolved mono and tributyltin concentrations. These results highlight the importance of taking into account factors other than light and nutrients, such as eco-toxic heavy metals, in understanding phytoplankton diversity and activity in estuarine ecosystems.
Show more [+] Less [-]Identification of genes expressed in juvenile Haliotis rufescens in response to different copper concentrations in the north of Chile under controlled conditions Full text
2011
Silva-Aciares, Fernando | Zapata, Manuel | Tournois, Jennifer | Moraga, Dario | Riquelme, Carlos
This study reports molecular markers potentially associated with resistance or sensitivity to the impact of copper in juvenile red abalone, Haliotis rufescens, in the north of Chile under experimental conditions. Genomic analysis was made applying subtractive hybridization libraries (SSH) to identify genes up-and down regulated during cooper exposure in abalone over periods of 12 and 168h exposed to 2.5 and 10μg/L of Cu⁺². Results obtained from the SSH library revealed 368 different sequences regulated by copper, that correspond to eight major physiological functions. The validation of these sequences obtained by SSH as well as their expression kinetics were made by PCR in real time on 14 potential genes regulated by metal stress. This study provides information for the characterization of potential genomic markers that may be used in future environmental monitoring and to investigate new mechanisms of stress to copper in this commercially important marine species.
Show more [+] Less [-]Assessment of sacrificial anode impact by aluminum accumulation in mussel Mytilus edulis: A large-scale laboratory test Full text
2011
Mao, Andrea | Mahaut, Marie-Laure | Pineau, Samuel | Barillier, Daniel | Caplat, Christelle
Since the early 1960s, the application of aluminum alloy sacrificial anodes to mitigate marine corrosion has been well known. The aim of this work was to study aluminum bioconcentration in Mytilus edulis by an in vitro test performed in two tanks: the first containing non-contaminated water (NCW) and the second containing aluminum-contaminated water (CW) (530μgL⁻¹) released by sacrificial anode. The mussels were collected and examined over a period of 8weeks. A comparison between the aluminum concentrations in the digestive glands of mussels from the CW and NCW tanks shows that the highest value (1700mg/kgd.w.) was found in the CW mussels collected after 13days. In NCW, the mean aluminum concentration in digestive glands during the test was 281mg/kgd.w. The rapid concentration decrease in digestive glands is probably due to the inhibition of filtering activity due to valve closure at the high concentration as well as the induction of the detoxification response.
Show more [+] Less [-]Effects of the 2003 European heatwave on the benthic community of a severe transitional ecosystem (Comacchio Saltworks, Italy) Full text
2011
Munari, Cristina
The summer of 2003 was the warmest summer in Europe since the 16th century. Its consequences on the fauna of a transitional ecosystem were studied through biodiversity, functional and ecological indicators, from summer 2002 to winter 2005. The heatwave caused considerable changes in the benthic community structure and relative composition, persisting in 2005. Animal assemblages switched from mollusc- to annelida-dominated. Biodiversity and functional indicators captured changes in community structure and composition, proving to be powerful tools to detect responses related to global warming. Ecological indicators rendered a monotonic response oscillating between bad and poor ecological status across the study period. The resilience of mollusc biocoenosis resulted limited with respect to other taxa, posing concerns about their conservation if, as predicted, the frequency of summers as hot as that of 2003 will progressively increase to become the norm at the end of this century.
Show more [+] Less [-]Spatial and temporal changes in microbial diversity of the Marmara Sea Sediments Full text
2011
Kolukirik, M. | Ince, O. | Cetecioglu, Z. | Celikkol, S. | Ince, B.K.
Spatial (10 different locations) and temporal (2years) changes in characteristics of the Marmara Sea Sediments were monitored to determine interactions between the chemical and microbial diversity. The sediments were rich in terms of hydrocarbon, nitrate, Ni and microbial cell content. Denitrifying, sulfate reducing, fermentative and methanogenic organisms were co-abundant in 15cm below the sea floor. The local variations in the sediments’ characteristics were more distinctive than the temporal ones. The sulfate and nitrate contents were the main drivers of the changes in the microbial community compositions. N and P were limited for microbial growth in the sediments, and their levels determined the total cell abundance and activity. Seasonal shifts in temperatures of the shallow sediments were also reflected in the active cell abundances. It was concluded that the Marmara Sea is a promising ecosystem for the further investigation of the ecologically important microbial processes.
Show more [+] Less [-]Decrease of Zn, Cd and Pb concentrations in marine fish species over a decade as response to reduction of anthropogenic inputs: The example of Tagus estuary Full text
2011
Raimundo, Joana | Pereira, Patrícia | Caetano, Miguel | Cabrita, Maria Teresa | Vale, Carlos
Concentrations of Zn, Cd and Pb were measured in muscle of pelagic, demersal and benthic fishes, captured in the coastal area adjoining the Tagus estuary (Portugal), in 1998 and 2010. Additionally, Pb and Cd were determined in estuarine waters, showing a pronounced decrease between 1999 and 2010. Accordingly, specimens captured in 2010 presented significantly lower metal concentrations than individuals caught in 1998. Reductions were more evident for Pb (reduction of 59–99%) than for Cd (14–93%) and Zn (17–54%). Values in pelagic and demersal species exhibited higher reductions than in benthic species. Decrease of metal concentrations in fish appears thus to reflect the improvement of estuarine water quality as anthropogenic sources have been reduced or eliminated. Furthermore, it emphasises the usefulness of the descriptor “Contaminants in Fish” to assess the efficiency of measures to achieve a good environmental status, in the scope of the Marine Strategy Framework Directive.
Show more [+] Less [-]Perfluorinated alkyl acids in water, sediment and wildlife from Sydney Harbour and surroundings Full text
2011
Thompson, Jack | Roach, Anthony | Eaglesham, Geoff | Bartkow, Michael E. | Edge, Katelyn | Mueller, Jochen F.
Perfluorinated alkyl compounds (PFCs) including perfluorooctane sulphonate (PFOS) and perfluorooctanoate (PFOA) were measured in environmental samples collected from around Homebush Bay, an urban/industrial area in the upper reaches of Sydney Harbour and Parramatta River estuary. Water, surface sediment, Sea Mullet (Mugil cephalus), Sydney Rock Oyster (Saccostrea commercialis) and eggs of two bird species; White Ibis (Threskiornis molucca), and Silver Gull (Larus novaehollandiae) were analysed. In most samples PFOS was the dominant PFC. Geometric mean PFOS concentrations were 33ng/gww (wet weight) in gull eggs, 34ng/gww in ibis eggs, and 1.8ng/gww and 66ng/gww in Sea Mullet muscle and liver, respectively. In sediment the PFOS geometric mean was 1.5ng/g, in water average PFOS and PFOA concentrations ranged from 7.5 to 21ng/L and 4.2 to 6.4ng/L, respectively. In oysters perfluorododecanoic acid was most abundant, with a geometric mean of 2.5ng/gww.
Show more [+] Less [-]Immune responses to combined effect of hypoxia and high temperature in the green-lipped mussel Perna viridis Full text
2011
Wang, Youji | Hu, Menghong | Shin, Paul K.S. | Cheung, Siu Gin
Flow cytometry was used to examine immune responses in haemocytes of the green-lipped mussel Perna viridis under six combinations of oxygen level (1.5mg O₂l⁻¹, 6.0mg O₂l⁻¹) and temperature (20°C, 25°C and 30°C) at 24h, 48h, 96h and 168h. The mussels were then transferred to normoxic condition (6.0mg O₂l⁻¹) at 20°C for further 24h to study their recovery from the combined hypoxic and temperature stress. Esterase (Est), reactive oxygen species (ROS), lysosome content (Lyso) and phagocytosis (Pha) were reduced at high temperatures, whereas hypoxia resulted in higher haemocyte mortality (HM) and reduced phagocytosis. For HM and Pha, changes were observed after being exposed to the stresses for 96h, whereas only a 24h period was required for ROS and Lyso, and a 48h one for Est. Recovery from the stresses was observed for HM and Pha but not other immune responses.
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