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Mercury in muscle and liver of ten ray species from Northwest Mexico Texto completo
2013
Ruelas-Inzunza, J. | Escobar-Sánchez, O. | Patrón-Gómez, J. | Moreno-Sánchez, X.G. | Murillo-Olmeda, A. | Spanopoulos-Hernández, M. | Corro-Espinosa, D.
We determined total mercury (Hg) distribution in muscle and liver of ten ray species and assessed health risk considering Hg levels in muscle and average consumption of rays in Mexico. Rays were collected from five sites in NW Mexico between March and November 2012. Hg concentrations ranged from 4.465μgg−1 in muscle of the longtail stingray Dasyatis longa to 0.036μgg−1 in liver of the diamond stingray Dasyatis dipterura. Considering all the individuals, Hg in muscle (1.612±1.322μgg−1) was significantly (p<0.05) higher than in liver (0.745±0.616μgg−1). Regarding local health risk assessment, none of the ray species may cause adverse effects on consumers.
Mostrar más [+] Menos [-]Geo-Chip analysis reveals reduced functional diversity of the bacterial community at a dumping site for dredged Elbe sediment Texto completo
2013
Störmer, Rebecca | Wichels, Antje | Gerdts, Gunnar
Geo-Chip analysis reveals reduced functional diversity of the bacterial community at a dumping site for dredged Elbe sediment Texto completo
2013
Störmer, Rebecca | Wichels, Antje | Gerdts, Gunnar
The dumping of dredged sediments represents a major stressor for coastal ecosystems. The impact on the ecosystem function is determined by its complexity not easy to assess. In the present study, we evaluated the potential of bacterial community analyses to act as ecological indicators in environmental monitoring programmes. We investigated the functional structure of bacterial communities, applying functional gene arrays (GeoChip4.2). The relationship between functional genes and environmental factors was analysed using distance-based multivariate multiple regression. Apparently, both the function and structure of the bacterial communities are impacted by dumping activities. The bacterial community at the dumping centre displayed a significant reduction of its entire functional diversity compared with that found at a reference site. DDX compounds separated bacterial communities of the dumping site from those of un-impacted sites. Thus, bacterial community analyses show great potential as ecological indicators in environmental monitoring.
Mostrar más [+] Menos [-]Geo-Chip analysis reveals reduced functional diversity of the bacterial community at a dumping site for dredged Elbe sediment Texto completo
2013
Störmer, Rebecca | Wichels, Antje | Gerdts, Gunnar
The dumping of dredged sediments represents a major stressor for coastal ecosystems. The impact on the ecosystem function is determined by its complexity not easy to assess. In the present study, we evaluated the potential of bacterial community analyses to act as ecological indicators in environmental monitoring programmes. We investigated the functional structure of bacterial communities, applying functional gene arrays (GeoChip 4.2). The relationship between functional genes and environmental factors was analysed using distance-based multivariate multiple regression. Apparently, both the function and structure of the bacterial communities are impacted by dumping activities. The bacterial community at the dumping centre displayed a significant reduction of its entire functional diversity compared with that found at a reference site. DDX compounds separated bacterial communities of the dumping site from those of un-impacted sites. Thus, bacterial community analyses show great potential as ecological indicators in environmental monitoring.
Mostrar más [+] Menos [-]Relationship between wind and seagrass meadows in a non-tidal eutrophic lagoon studied by a Wave Exposure Model (WEMo) Texto completo
2013
Rubegni, Fabrizio | Franchi, Enrica | Lenzi, Mauro
The hydrodynamic action of wind and the distribution of biomass of seagrass meadows in a non-tidal eutrophic lagoon (Orbetello Lagoon, Tuscany, Italy) were analysed for correlations by simulation with a Wave Exposure Model (WEMo) on 5-year data series. WEMo and statistical analysis established a weak direct correlation between the areas that the model identified as being subject to resuspension and transport of sediment and those actually colonised by seagrass. A significant difference was found between surface and bottom hydrodynamics. The areas that the model identified as exposed to higher energy surface hydrodynamics proved to be inversely correlated with seagrass biomass. Multivariate statistical analysis ordered the model variables according to their relative importance. The model indicated the need for further study, demonstrating its utility for environmental management of eutrophic lagoons.
Mostrar más [+] Menos [-]Efficient tools for marine operational forecast and oil spill tracking Texto completo
2013
Marta-Almeida, Martinho | Ruiz-Villarreal, Manuel | Pereira, Janini | Otero, Pablo | Cirano, Mauro | Zhang, Xiaoqian | Hetland, Robert D
Efficient tools for marine operational forecast and oil spill tracking Texto completo
2013
Marta-Almeida, Martinho | Ruiz-Villarreal, Manuel | Pereira, Janini | Otero, Pablo | Cirano, Mauro | Zhang, Xiaoqian | Hetland, Robert D
Ocean forecasting and oil spill modelling and tracking are complex activities requiring specialised institutions. In this work we present a lighter solution based on the Operational Ocean Forecast Python Engine (OOFε) and the oil spill model General NOAA Operational Modelling Environment (GNOME). These two are robust relocatable and simple to implement and maintain. Implementations of the operational engine in three different regions with distinct oceanic systems, using the ocean model Regional Ocean Modelling System (ROMS), are described, namely the Galician region, the southeastern Brazilian waters and the Texas–Louisiana shelf. GNOME was able to simulate the fate of the Prestige oil spill (Galicia) and compared well with observations of the Krimsk accident (Texas). Scenarios of hypothetical spills in Campos Basin (Brazil) are illustrated, evidencing the sensitiveness to the dynamical system.OOFε and GNOME are proved to be valuable, efficient and low cost tools and can be seen as an intermediate stage towards more complex operational implementations of ocean forecasting and oil spill modelling strategies.
Mostrar más [+] Menos [-]Efficient tools for marine operational forecast and oil spill tracking Texto completo
2013
Marta-Almeida, Martinho | Ruiz-Villarreal, Manuel | Pereira, J. | Otero, Pablo | Cirano, Mauro | Zhang, Xiaoqian | Hetland, R.D.
Ocean forecasting and oil spill modelling and tracking are complex activities requiring specialised institutions. In this work we present a lighter solution based on the Operational Ocean Forecast Python Engine (OOFε) and the oil spill model General NOAA Operational Modelling Environment (GNOME). These two are robust relocatable and simple to implement and maintain. Implementations of the operational engine in three different regions with distinct oceanic systems, using the ocean model Regional Ocean Modelling System (ROMS), are described, namely the Galician region, the southeastern Brazilian waters and the Texas–Louisiana shelf. GNOME was able to simulate the fate of the Prestige oil spill (Galicia) and compared well with observations of the Krimsk accident (Texas). Scenarios of hypothetical spills in Campos Basin (Brazil) are illustrated, evidencing the sensitiveness to the dynamical system. OOFε and GNOME are proved to be valuable, efficient and low cost tools and can be seen as an intermediate stage towards more complex operational implementations of ocean forecasting and oil spill modelling strategies. | Sí
Mostrar más [+] Menos [-]Trace metals pollution in seawater and groundwater in the ship breaking area of Sitakund Upazilla, Chittagong, Bangladesh Texto completo
2013
Hasan, Asma Binta | Kabir, Sohail | Selim Reza, A.H.M. | Zaman, Mohammad Nazim | Ahsan, Mohammad Aminul | Akbor, Mohammad Ahedul | Raśīda, Mohāmmada Māmunura
This study reveals potential accumulation of trace metals in the sea and groundwater due to ship breaking activities which take place along the Bay of Bengal in Sitakund Upazilla, Chittagong, Bangladesh. When compared with WHO and Bangladesh domestic standards for water quality, it is revealed that seawater was strongly polluted by Fe and Hg, moderately by Mn and Al, and slightly by Pb and Cd. Groundwater was strongly polluted by Fe, Pb and Hg, moderately by Mn and Al, and slightly by As. Trace element concentrations of all seawater samples exceeded the average concentration of elements in the Earth’s seawater. The application of Principal Components Analysis identified two sources of pollution–marine and ship breaking. The mechanism of groundwater pollution inferred that if seawater is polluted, nearby groundwater is also polluted with trace metals due to the influence of seawater intrusion.
Mostrar más [+] Menos [-]Cumulative impacts on seabed habitats: An indicator for assessments of good environmental status Texto completo
2013
Korpinen, Samuli | Meidinger, Manuel | Laamanen, Maria
The European seas are under anthropogenic pressures impacting the state of water quality, benthic habitats and species. The EU Marine Strategy Framework Directive (MSFD) requires the Member States to assess the impacts of pressures and make a programme of measures leading to good environmental status (GES) by 2020. This study presents a method for assessing the quantity and distribution of anthropogenic impacts on benthic habitats in the Baltic Sea by using spatial data of human pressures and benthic habitats. The southern sub-basins were more extensively impacted than the northern sub-basins. Over the entire sea area, deep sea habitats were more impacted than shallower infralittoral and circalittoral habitats. Sand and coarse sediments were the seabed types relatively most impacted in the Baltic Sea scale. A comparison against tentative thresholds for GES showed that in the sub-basin scale only one third of the habitat types was in GES.
Mostrar más [+] Menos [-]Toxicity of Epoxiconazole to the Marine Diatom Chaetoceros calcitrans: Influence of Growth Conditions and Algal Development Stage Texto completo
2013
Amara, Anis | Quiniou, Francoise | Durand, Gael | El Bour, Monia | Boudabous, Abdellatif | Hourmant, Annick
The triazole fungicide epoxiconazole is extensively used to control fungi on crops and may present some potential risk from runoff on coastal ecosystems located close to agricultural areas. Phytotoxicity assessments were conducted on the marine diatom Chaetoceros calcitrans using both the active ingredient and its formulated product (Opus). The 3-day EC50 using cell count was 2.31 mg/L for epoxiconazole active ingredient and 2.9 mu g/L for epoxiconazole-formulated. The fungicide produced an increase of cellular volume, pigment (chlorophylls a, c, and carotenoids) content, ATP synthesis, and rates of photosynthesis and respiration. Progressive algal cell recovery from epoxiconazole effects occurred after 3 days, with the increasing cell density. Differences in cell age, light, and nutrient composition induced changes in epoxiconazole sensitivity. Since these parameters affect cellular division rates, the cellular density is an important parameter in toxicity tests.
Mostrar más [+] Menos [-]Accumulated sediments in a detention basin: chemical and microbial hazard assessment linked to hydrological processes Texto completo
2013
Sébastian, C. | Barraud, S. | Ribun, Sébastien | Zoropogui, A. | Blaha, Didier | Becouze-Lareure, C. | Kouyi, G. Lipeme | Cournoyer, B. | Laboratoire d'Ecologie Microbienne - UMR 5557 (LEM) ; Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Ecole Nationale Vétérinaire de Lyon (ENVL)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)
International audience | Accumulated sediments in a 32,000-m3 detention basin linked to a separate stormwater system were characterized in order to infer their health hazards. A sampling scheme of 15 points was defined according to the hydrological behaviour of the basin. Physical parameters (particle size and volatile organic matter content) were in the range of those previously reported for stormwater sediments. Chemical analyses on hydrocarbons, PAHs, PCBs and heavy metals showed high pollutant concentrations. Microbiological analyses of these points highlighted the presence of faecal indicator bacteria (Escherichia coli and intestinal enterococci) and actinomycetes of the genus Nocardia. These are indicative of the presence of human pathogens. E. coli and enterococcal numbers in the sediments were higher at the proximity of the low-flow gutter receiving waters from the catchment. These bacteria appeared to persist over time among urban sediments. Samples highly contaminated by hydrocarbons were also shown to be heavily contaminated by these bacteria. These results demonstrated for the first time the presence of Nocardial actinomycetes in such an urban context with concentrations as high as 11,400 cfu g-1.
Mostrar más [+] Menos [-]Marine debris in mangroves and on the seabed: largely-neglected litter problems : editorial
2013
Debrot, A.O. | Bron, P.S. | Leon, R. | Meesters, H.W.G.
Impact of flood events on macrobenthic community structure on an intertidal flat developing in the Ohta River Estuary Texto completo
2013
Nishijima, Wataru | Nakano, Yoichi | Nakai, Satoshi | Okuda, Tetsuji | Imai, Tsuyoshi | Okada, Mitsumasa
We investigated the effects of river floods on the macrobenthic community of the intertidal flat in the Ohta River Estuary, Japan, from 2005 to 2010. Sediment erosion by flood events ranged from about 2–3cm to 12cm, and the salinity dropped to 0‰ even during low-intensity flood events. Cluster analysis of the macrobenthic population showed that the community structure was controlled by the physical disturbance, decreased salinity, or both. The opportunistic polychaete Capitella sp. was the most dominant species in all clusters, and populations of the long-lived polychaete Ceratonereis erythraeensis increased in years with stable flow and almost disappeared in years with intense flooding. The bivalve Musculista senhousia was also an important opportunistic species that formed mats in summer of the stable years and influenced the structure of the macrobenthic community. Our results demonstrate the substantial effects of flood events on the macrobenthic community structure.
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