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Driving factors behind the distribution of dinocyst composition and abundance in surface sediments in a western Mediterranean coastal lagoon: Report from a high resolution mapping study Texte intégral
2014
Fertouna-Bellakhal, Mouna | Dhib, Amel | Béjaoui, Béchir | Turki, Souad | Aleya, Lotfi
Species composition and abundance of dinocysts in relation to environmental factors were studied at 123 stations of surface sediment in Bizerte Lagoon. Forty-eight dinocyst types were identified, mainly dominated by Brigantidinium simplex, Votadinum spinosum, Alexandrium pseudogonyaulax, Alexandrium catenella, and Lingulodinum machaerophorum along with many round brown cysts and spiny round brown cysts. Cysts ranged from 1276 to 20126cystsg−1dry weight sediment. Significant differences in cyst distribution pattern were recorded among the zones, with a higher cyst abundance occurring in the lagoon’s inner areas. Redundancy analyses showed two distinct associations of dinocysts according to location and environmental variables. Ballast water discharges are potential introducers of non-indigenous species, especially harmful ones such as A. catenella and Polysphaeridium zoharyi, with currents playing a pivotal role in cyst distribution. Findings concerning harmful cyst species indicate potential seedbeds for initiation of future blooms and outbreaks of potentially toxic species in the lagoon.
Afficher plus [+] Moins [-]Sediment PAH: Contrasting levels in the Caspian Sea and Anzali Wetland Texte intégral
2014
Yancheshmeh, Rokhsareh Azimi | Bakhtiari, Alireza Riyahi | Mortazavi, Samar | Savabieasfahani, Mozhgan
A comparative study of 23 PAH congeners in sediment of the Caspian Sea coast and Anzali Wetland was conducted in 2010. Surface sediment was analyzed using chromatography and mass spectrometry. Total PAH concentrations ranged between 212 and 9009ngg−1dw. Spatial distribution maps revealed that PAH levels were higher in the coastal areas of the Caspian Sea where oil related activities have been common since 1800’s. Diagnostic ratios analysis indicated that PAHs largely originated from petrogenic processes. PAH toxicity level was assessed using sediment quality guidelines and toxic equivalent concentrations to determine toxic effects on marine organism. Based on these investigations, in our study areas, the probability of toxicity for benthic organisms is “low to medium”. The toxic equivalent concentrations of carcinogenic PAHs varied between 11 and 231ng TEQ/g; higher total toxic equivalent concentrations values were found in the coastal areas of the Caspian Sea.
Afficher plus [+] Moins [-]Human health risk of polycyclic aromatic hydrocarbons from consumption of blood cockle and exposure to contaminated sediments and water along the Klang Strait, Malaysia Texte intégral
2014
Tavakoly Sany, Seyedeh Belin | Hashim, Rosli | Rezayi, Majid | Salleh, Aishah | Rahman, M. Azizur (Mohammad Azizur) | Safari, Omid | Sasekumar, A.
The concentration of carcinogenic poly aromatic hydrocarbons (c-PAHs) present in water and sediment of Klang Strait as well as in the edible tissue of blood cockle (Anadara granosa) was investigated.The human health risk of c-PAHs was assessed in accordance with the standards of the United States Environmental Protection Agency (US EPA). The cancer risks of c-PAHs to human are expected to occur through the consumption of blood cockles or via gastrointestinal exposure to polluted sediments and water in Kalng Strait. The non-carcinogenic risks that are associated with multiple pathways based on ingestion rate and contact rates with water were higher than the US EPA safe level at almost all stations, but the non-carcinogenic risks for eating blood cockle was below the level of US EPA concern. A high correlation between concentrations of c-PAHs in different matrices showed that the bioaccumulation of c-PAHs by blood cockles could be regarded as a potential health hazard for the consumers.
Afficher plus [+] Moins [-]Trace element contamination in the Guadalquivir River Estuary ten years after the Aznalcóllar mine spill Texte intégral
2014
Tornero, Victoria | Arias, Alberto M. | Blasco, Julián
Trace element contamination in the Guadalquivir River Estuary ten years after the Aznalcóllar mine spill Texte intégral
2014
Tornero, Victoria | Arias, Alberto M. | Blasco, Julián
Sediments, clams Scrobicularia plana and worms Hediste diversicolor from the Guadalquivir estuary were collected ten years after the Aznalcóllar mine spill and analyzed for metals. Significant seasonal and spatial effects were detected for most elements, so data from different sampling periods and locations were treated separately. Overall, the most polluted sites were found upstream, although Zn and Cu tended to accumulate at the estuary mouth. A significant decline of Zn in sediments and clams was observed compared to levels reported following the spill, so the estuarine ecosystem has recovered. However, the concentrations of some elements in S. plana were still higher than those of heavily contaminated regions. In this mollusk, Pb and As levels were higher in 2008 than in previous years, suggesting a new source entering into the estuary. Metals in sediments presented low bioavailability for biota, so other sources must account for the concentrations observed in these species.
Afficher plus [+] Moins [-]Trace element contamination in the Guadalquivir River Estuary ten years after the Aznalcóllar mine spill Texte intégral
2014
Tornero, Victoria | Arias, Alberto M. | Blasco, Julián | European Commission | Ministerio de Ciencia y Tecnología (España)
Sediments, clams Scrobicularia plana and worms Hediste diversicolor from the Guadalquivir estuary were collected ten years after the Aznalcóllar mine spill and analyzed for metals. Significant seasonal and spatial effects were detected for most elements, so data from different sampling periods and locations were treated separately. Overall, the most polluted sites were found upstream, although Zn and Cu tended to accumulate at the estuary mouth. A significant decline of Zn in sediments and clams was observed compared to levels reported following the spill, so the estuarine ecosystem has recovered. However, the concentrations of some elements in S. plana were still higher than those of heavily contaminated regions. In this mollusk, Pb and As levels were higher in 2008 than in previous years, suggesting a new source entering into the estuary. Metals in sediments presented low bioavailability for biota, so other sources must account for the concentrations observed in these species. | While doing this work, V. Tornero was fully supported by a I3P contract from the Programa Nacional de Potenciación de Recursos Humanos del Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (2000–2003). The presented study was supported as a part of the projects CTM2005-07282-C03-02/TECNO (Spanish Science and Technology National Plan) and Interreg IIIA REDCONTAMAR SP5 (SP3.E101/03). | Peer reviewed
Afficher plus [+] Moins [-]Out of sight but not out of mind: Harmful effects of derelict traps in selected U.S. coastal waters Texte intégral
2014
Arthur, Courtney | Sutton-Grier, Ariana E. | Murphy, Peter | Bamford, Holly
There is a paucity of data in the published literature on the ecological and economic impacts of derelict fishing traps (DFTs) in coastal ecosystems. We synthesized results from seven NOAA-funded trap fisheries studies around the United States and determined that DFT-caused losses to habitat and harvestable annual catch are pervasive, persistent, and largely preventable. Based on this synthesis, we identified key gaps to fill in order to better manage and prevent DFTs. We conclude with suggestions for developing a U.S. DFT management strategy including: (1) targeting studies to estimate mortality of fishery stocks, (2) assessing the economic impacts of DFTs on fisheries, (3) collaborating with the fishing industry to develop solutions to ghost fishing, and (4) examining the regional context and challenges resulting in DFTs to find effective policy solutions to manage, reduce, and prevent gear loss.
Afficher plus [+] Moins [-]Marine litter in Mediterranean sandy littorals: Spatial distribution patterns along central Italy coastal dunes Texte intégral
2014
Poeta, Gianluca | Battisti, Corrado | Acosta, Alicia T.R.
Sandy shores are generally considered important sinks for marine litter and the presence of this litter may represent a serious threat to biotic communities and dune integrity mostly due to cleaning activities carried out through mechanical equipment. In spring (April–May) 2012 we sampled 153 2×2m random plots to assess the spatial distribution patterns of litter on Central Italy sandy shores. We analysed the relationship between the presence of litter and coastal dune habitats along the sea-inland gradient. Our results showed that the most frequent litter items were plastic and polystyrene. Differences of marine litter spatial distribution were found between upper beach and fore dune habitats and fixed dune habitats: embryo dune and mobile dune habitats show the highest frequency of litter, but, surprisingly, marine litter did not impact fixed dune habitats, these possibly acting as a natural barrier protecting the inner part of the coast from marine litter dispersion.
Afficher plus [+] Moins [-]Occurrence and distribution of phthalate esters in riverine sediments from the Pearl River Delta region, South China Texte intégral
2014
Liu, Hong | Cui, Kunyan | Zeng, Feng | Chen, Lixuan | Cheng, Yating | Li, Huiru | Li, Shuocong | Zhou, Xi | Zhu, Fang | Ouyang, Gangfeng | Luan, Tiangang | Zeng, Zunxiang
Sixty-eight sediment samples collected from Dongjiang River, Xijiang River, Beijiang River and Zhujiang River in the Pearl River Delta (PRD) region, Southern China, were analyzed for 16 phthalate esters (PAEs). PAEs were detected in all riverine sediments analyzed, which indicate that PAEs are ubiquitous environmental contaminants. The Σ16PAEs concentrations in riverine sediments in the PRD region ranged from 0.567 to 47.3μgg−1 dry weight (dw), with the mean and median concentrations of 5.34μgg−1dw and 2.15μgg−1dw, respectively. Elevated PAEs concentrations in riverine sediments in the PRD region were found in the highly urbanized and industrialized areas. Of the 16 PAEs, diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP) dominated the PAEs, with the mean and median concentrations of 1.12μgg−1dw, 0.420μgg−1dw and 3.72μgg−1dw, and 0.429μgg−1dw, 0.152μgg−1dw and 1.55μgg−1dw, respectively, and accounted for 94.2–99.7% of the Σ16PAEs concentrations. Influenced by local sources and the properties of PAEs, a gradient trend of concentrations and a fractionation of composition from more to less industrialized and urbanized areas were discovered. As compared to the results from other studies, the riverine sediments in the PRD region were severely contaminated with PAEs. Information about PAEs contamination status and its effect on the aquatic organisms in the PRD region may deserve further attention.
Afficher plus [+] Moins [-]Monitoring plant response to phenanthrene using the red edge of canopy hyperspectral reflectance Texte intégral
2014
Zhu, Linhai | Chen, Zhongxin | Wang, Jianjian | Ding, Jinzhi | Yu, Yunjiang | Li, Junsheng | Xiao, Nengwen | Jiang, Lianhe | Zheng, Yuanrun | Rimmington, Glyn M.
To investigate the mechanisms and potential for the remote sensing of phenanthrene-induced vegetation stress, we measured field canopy spectra, and associated plant and soil parameters in the field controlled experiment in the Yellow River Delta of China. Two widely distributed plant communities, separately dominated by reed (Phragmites australis) and glaucous seepweed (Suaeda salsa), were treated with different doses of phenanthrene. The canopy spectral changes of plant community resulted from the decreases of biomass and foliar projective coverage, while leaf photosynthetic pigment concentrations showed no significance difference among treatments. The spectral response to phenanthrene included a flattened red edge, with decreased first derivative of reflectance. The red edge slope and area consistently responded to phenanthrene, showing a strong relationship with aboveground biomass, coverage and canopy pigments density. These results suggest the potential of remote sensing and the importance of field validation to correctly interpret the causes of the spectral changes.
Afficher plus [+] Moins [-]Impact of rainfall on the hygienic quality of blue mussels and water in urban areas in the Inner Oslofjord, Norway Texte intégral
2014
Tryland, Ingun | Myrmel, Mette | Østensvik, Øyvin | Wennberg, Aina C. | Robertson, Lucy J.
The effects of precipitation on the hygienic quality of water and blue mussels collected from five different localities in the urban areas in the Inner Oslofjord were investigated, with samples analysed for Escherichia coli, Salmonella spp., pathogenic Vibrio spp., Norovirus, Sapovirus, Cryptosporidium spp. and Giardia duodenalis. The sampling sites were located at varying distances from the outlet of combined sewer overflows (CSO)-impacted rivers/streams. In general, 1–3 log10 increases in fecal indicator bacteria and human pathogens were observed after heavy rainfalls. Blue mussels appeared to be a useful indicator of the impact of sewage at these sites, and generally a good correlation was identified between concentrations of E. coli and other human pathogens in the mussels. Provision of general advice to the public of avoiding areas near the outlets of CSO-impacted rivers after heavy rainfall may reduce the risk of gastroenteritis by bathers and others that may swallow water during recreational activities.
Afficher plus [+] Moins [-]Assessment of TBT and organic booster biocide contamination in seawater from coastal areas of South Korea Texte intégral
2014
Kim, Nam Sook | Shim, Won Joon | Yim, Un Hyuk | Hong, Sang Hee | Ha, Sung Yong | Han, Gi Myung | Shin, Kyung-Hoon
Seawater samples from major enclosed bays, fishing ports, and harbors of Korea were analyzed to determine levels of tributyltin (TBT) and booster biocides, which are antifouling agents used as alternatives to TBT. TBT levels were in the range of not detected (nd) to 23.9ng Sn/L. Diuron and Irgarol 1051, at concentration ranges of 35–1360ng/L and nd to 14ng/L, respectively, were the most common alternative biocides present in seawater, with the highest concentrations detected in fishing ports. Hot spots were identified where TBT levels exceeded environmental quality targets even 6years after a total ban on its use in Korea. Diuron exceeded the UK environmental quality standard (EQS) value in 73% of the fishing port samples, 64% of the major bays, and 42% of the harbors. Irgarol 1051 levels were marginally below the Dutch and UK EQS values at all sites.
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