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Evaluation for coastal reclamation feasibility using a comprehensive hydrodynamic framework: A case study in Haizhou Bay Texto completo
2015
Feng, Lan | He, Jia | Ai, Junyong | Sun, Xiang | Bian, Fangyuan | Zhu, Xiaodong
Coastal reclamation (CR) is a prevailing approach to solve the contradiction between the land shortage and the growing demand of living space for human beings. In general, environmental impact assessment (EIA) focuses on evaluating the feasibility of individual coastal reclamation project (CRP). However, few studies have investigated the cumulative effect of multiple CRPs on surrounding environment. In this study, an integrated framework based on coastal hydrodynamics was established, and then applied to the feasibility evaluation of multiple CRPs for future coastal management in Haizhou Bay, China. The results indicated that three out of five reclamation projects were feasible and the remaining two were forbidden in the study area, whereas EIA approves of all the CRPs. It provides a scientific reference for effective management of coastal reclamation and future environmental impact researches when new CRPs are proposed.
Mostrar más [+] Menos [-]Assessment of the European flounder responses to chemical stress in the English Channel, considering biomarkers and life history traits Texto completo
2015
Dupuy, Célie | Galland, Claire | Pichereau, Vianney | Sanchez, Wilfried | Riso, Ricardo | Labonne, Maylis | Amara, Rachid | Charrier, Grégory | Fournier, Michel | Laroche, Jean
A multi-biomarker approach was developed to evaluate responses of European flounder (Platichthys flesus) in three contrasted estuaries over the English Channel: the Canche (pristine site), Tamar (heavy metals and PAHs contamination) and Seine (heavily pollution with a complex cocktail of contaminants). The condition factor and several biomarkers of the immune system, antioxidant enzymes, energetic metabolism and detoxification processes were investigated in young-of-the-year (0+) and one-year-old (1+) flounder. Results underlined the difference between the pristine site and the Seine estuary which showed a lower condition factor, a modulation of the immune system, a higher Cytochrome C oxidase activity, and an up-regulation of BHMT expression. The moderate biomarker responses in the Tamar fish could be linked to the specific contamination context of this estuary. Flounder life history traits were analyzed by otolith microchemistry, in order to depict how the fish use their habitat and thus respond to chemical stress in estuaries.
Mostrar más [+] Menos [-]Repeated rapid assessment surveys reveal contrasting trends in occupancy of marinas by non-indigenous species on opposite sides of the western English Channel Texto completo
2015
Bishop, John D.D. | Wood, Christine A. | Lévêque, Laurent | Yunnie, Anna L.E. | Viard, Frédérique
Rapid assessment surveys of non-indigenous species (NIS) of sessile invertebrates were made at seven marinas in NW France and 10 marinas in SW England in 2010, and repeated in 2013. Fourteen NIS were recorded, 12 of which were seen on both coasts. Site occupancy differed between the opposite sides of the western English Channel. In Brittany, most species occurred at most sites in both 2010 and 2013. In 2010, site occupancy in Devon & Cornwall was distinctly lower; by 2013, the difference compared to Brittany had narrowed considerably, largely because of rapid colonisation of additional sites by species that were infrequent in 2010. Three more of the recent NIS are present in Devon & Cornwall but have still not become widespread. It is concluded that the recently introduced fouling animals studied here are longer established in NW France than in SW England, and have probably spread northwards across the Channel.
Mostrar más [+] Menos [-]Environmental fate and ecological risks of nonylphenols and bisphenol A in the Cape D’Aguilar Marine Reserve, Hong Kong Texto completo
2015
Xu, Elvis G.B. | Morton, Brian | Lee, Joseph H.W. | Leung, Kenneth M.Y.
Nonylphenols (NPs) and bisphenol A (BPA) are the most common endocrine disruptors detected in the coastal waters of Hong Kong. The Cape D’Aguilar Marine Reserve (CAMR), the only marine reserve in Hong Kong is close to urbanized areas, thus the resident marine organisms are inevitably influenced by partially treated wastewater from adjacent sewage treatment plants (STPs). Elevated levels of NPs and BPA were detected in all seawater, sediment and biota samples collected from the CAMR. Estrogenic activities of seawater from the CAMR, and sludge and sewage from a nearby STP were assessed using yeast estrogen screen assay. We found aromatase, estrogen receptor and vitellogenin genes in the marine medaka fish Oryzias melastigma were significantly up-regulated after exposure to the reserve’s seawater. According to a tissue-residue-based probabilistic risk assessment, the marine species living in the CAMR are having 35% and 21% of chance to be at risk due to exposure to NPs and BPA, respectively.
Mostrar más [+] Menos [-]Assessment of swimming associated health effects in marine bathing beach: An example from Morib beach (Malaysia) Texto completo
2015
Praveena, Sarva Mangala | Pauzi, Norfasmawati Mohd | Hamdan, Munashamimi | Sham, Shaharuddin Mohd
A survey among beachgoers was conducted to determine the swimming associated health effects experienced and its relationship with beach water exposure behaviour in Morib beach. For beach water exposure behaviour, the highest frequency of visit among the respondents was once a year (41.9%). For ways of water exposure, whole body exposure including head was the highest (38.5%). For duration of water exposure, 30.8% respondents prefer to be in water for about 30min with low possibilities of accidental ingestion of beach water. A total of 30.8% of beachgoers in Morib beach were reported of having dermal symptoms. Bivariate analysis showed only water activity, water contact and accidental ingestion of beach water showed significant association with swimming associated health effects experienced by swimmers. This study output showed that epidemiological study can be used to identify swimming associated health effects in beach water exposed to faecal contamination.
Mostrar más [+] Menos [-]Does the chronic chemical contamination of a European flounder population decrease its thermal tolerance? Texto completo
2015
Lavergne, Edouard | Pedron, Nicolas | Calves, Isabelle | Claireaux, Guy | Mazurais, David | Zambonino-Infante, José | Le Bayon, Nicolas | Cahu, Chantal | Laroche, Jean
Juvenile flounders (Platichthys flesus), collected in two estuaries with similar temperature regimes (the heavily polluted Seine and the moderately contaminated Vilaine), were submitted to a common garden experiment. After an acclimation period, both populations were challenged by a thermal stress (9–24°C for 15days, then maintenance at 24°C for 19days). The condition factor of the Vilaine fish increased in both conditions, while it decreased for the heated Seine flounders after 34days. The expression of genes related to the energetic metabolism was measured in the liver. The expression levels for ATP-F0 and COII were significantly reduced for heated vs. standard fish from both estuaries, while a decrease of the 12S expression was detected only in heated vs. standard fish from the Seine estuary. Thus, it is suggested that highly contaminated fish from Seine could display a lower tolerance to thermal stress, compared to moderately contaminated fish from Vilaine.
Mostrar más [+] Menos [-]Spatial variability of three benthic indices for marine quality assessment in a subtropical estuary of Southern Brazil Texto completo
2015
Brauko, Kalina Manabe | Souza, Fernanda Maria de | Muniz, Pablo | Camargo, Maurício Garcia de | Lana, Paulo da Cunha
Indices based on macrobenthic responses to disturbance remain to be adequately tested for the detection of spatial variability by robust sampling designs. We present herein a congruence test to real-world data of the widely used indices AMBI, M-AMBI and BENTIX in tidal flats of a subtropical estuary. We used a hierarchical sampling design to evaluate the spatial variability of the indices in response to distinct levels of sewage contamination. Indices were then tested for correlations with chemical proxies of contamination and for the similarity of responses. BENTIX and M-AMBI produced over- and underestimations of ecological status. We found a low degree of similarity among indices as an expression of the spatial variation of macrofaunal assemblages on their performances. Only AMBI varied at the contamination scale (103m) and was congruent with physical–chemical proxies. Ambiguous responses indicated effects of natural inputs of organic matter rather than environmental quality associated to sewage.
Mostrar más [+] Menos [-]Biotransformation of petroleum hydrocarbons and microbial communities in seawater with oil dispersions and copepod feces Texto completo
2015
Størdal, Ingvild Fladvad | Olsen, Anders Johny | Jenssen, Bjørn Munro | Netzer, Roman | Altin, Dag | Brakstad, Odd Gunnar
To determine biotransformation of components in crude oil dispersions in the presence of feces from marine copepods, dispersed oil was incubated alone, with the addition of clean or oil-containing feces. We hypothesized that the feces would contribute with nutrients to bacteria, and higher concentrations of oil-degrading bacteria, respectively. Presence of clean feces resulted in higher degradation of aromatic oil compounds, but lower degradation of n-alkanes. Presence of oil-containing feces resulted in higher degradation of n-alkanes. The effect of clean feces on aromatic compounds are suggested to be due to higher concentrations of nutrients in the seawater where aromatic degradation takes place, while the lower degradation of n-alkanes are suggested to be due to a preference by bacteria for feces over these compounds. Large aggregates were observed in oil dispersions with clean feces, which may cause sedimentation of un-weathered lipophilic oil compounds towards the seafloor if formed during oil spills.
Mostrar más [+] Menos [-]Mercury and selenium in seston, marine plankton and fish (Sardinella brasiliensis) as a tool for understanding a tropical food web Texto completo
2015
Seixas, Tércia Guedes | Moreira, Isabel | Kehrig, Helena Amaral
Mercury (Hg) and selenium (Se) concentrations were evaluated in a planktivorous fish and four size classes of organisms (FSCO), collected at an oligotrophic bay in the Southeastern Brazilian coast. No significant spatial differences between Hg and Se were found in the FSCO within the five sampling points in the bay. Hg and Se concentrations increased with successive increases in the size class of the analyzed plankton, i.e. approximately 3-and 2-fold, respectively, from microplankton to macroplankton. Hg and Se biomagnified throughout the planktonic food web. The smallest size class of organism, seston, composed of both biotic and abiotic portions, and fish showed the highest Hg concentrations. This indicates that Hg is not biomagnifying in the base of the bay food web. Selenium concentrations in fish were approximately 5.9 times higher than those in seston. Hg and Se concentrations in fish were approximately 3.5 and 14.6 times higher than those found in the plankton, respectively.
Mostrar más [+] Menos [-]A three-dimensional water quality model to evaluate the environmental capacity of nitrogen and phosphorus in Jiaozhou Bay, China Texto completo
2015
Li, Keqiang | Zhang, Li | Li, Yan | Zhang, Longjun | Wang, Xiulin
Jiaozhou Bay has recently suffered from serious problems with pollution and eutrophication. Thus, land-based pollutant load must be reduced through a national control program. In this study, we developed a 3D water quality model to determine the environmental capacity of nitrogen and phosphorus in Jiaozhou Bay. A 3D hydrodynamic model (the estuarine, coastal, and ocean modeling system with sediments) was coupled with a water quality model, which was adapted from the dynamic model of nitrogen and phosphorus for a mesocosm near Jiaozhou Bay. The water quality model is divided into seven components: dissolved inorganic nitrogen, phosphate, phytoplankton, zooplankton, detritus, dissolved organic nitrogen, and dissolved organic phosphorus. Furthermore, it was calibrated based on data collected from Jiaozhou Bay in 2003. The proposed model effectively reproduced the spatiotemporal variability in nutrient concentration, thus suggesting that a reasonable numerical representation of the prototype system must be developed for further evaluation of environmental capacity.
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