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Biofouling increases drag on marine vessels resulting in higher fuel consumption and can also facilitate the transport of harmful non-indigenous species (NIS). Antifouling technologies incorporating biocides (e.g., copper and tributyltin) have been developed to prevent settlement of organisms on vessels, but their widespread use has introduced high levels of contamination into the environment and raised concerns about their toxic effects on marine communities. The recent global ban on tributyltin (1 January 2008) and increasing regulation of copper have prompted research and development of non-toxic paints. This review synthesises existing information regarding the ecological impact of biocides in a wide range of organisms and highlights directions for the management of antifouling paints. We focus particularly on representatives of the recent past (copper and tributyltin) and present (copper and ‘booster’) biocides. We identify knowledge gaps in antifouling research and provide recommendations relating to the regulation and phasing-out of copper.  相似文献   
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We estimated the survival probability of breeding European storm petrels before, during and after a severe oil-spill. We hypothesized that petrels might have deserted the breeding colony to maximize their own survival probability and we expected no major change on adult survival probabilities as a consequence of the spill. We used an information-theoretical approach and multi-model inference to assess the strength of the evidence in favour of different hypotheses.Evidence contained in the data clearly supported the non-effect of the spill on adult survival hypothesis while punctual impact of the spill on survival and expanded (3 years) impact alternatives received less support. The effect size of the spill on averaged survival estimates was negligible in every case. We suggest that petrels minimized the impact of acute pollution by not investing in reproduction. We suggest that short-medium term management actions after oil-spills and similar catastrophes should focus on ecosystem restoration.  相似文献   
114.
Plastic debris ingestion by marine catfish: an unexpected fisheries impact   总被引:1,自引:0,他引:1  
Plastic marine debris is a pervasive type of pollution. River basins and estuaries are a source of plastics pollution for coastal waters and oceans. Estuarine fauna is therefore exposed to chronic plastic pollution. Three important catfish species [Cathorops spixii (N = 60), Cathorops agassizii (N = 60) and Sciades herzbergii (N = 62)] from South Western Atlantic estuaries were investigated in a tropical estuary of the Brazilian Northeast in relation to their accidental ingestion of plastic marine debris. Individuals from all three species had ingested plastics. In C. spixii and C. agassizii, 18% and 33% of individuals had plastic debris in their stomachs, respectively. S. herzbergii showed 18% of individuals were contaminated. All ontogenetic phases (juveniles, sub-adults and adults) were contaminated. Nylon fragments from cables used in fishery activities (subsistence, artisanal and commercial) played a major role in this contamination. These catfish spend their entire life cycles within the estuary and are an important feeding resource for larger, economically important, species. It is not yet possible to quantify the scale and depth of the consequences of this type of pollution. However, plastics are well known threat to living resources in this and other estuaries. Conservation actions will need to from now onto take plastics pollution into consideration.  相似文献   
115.
In remote, tropical areas human influences increase, potentially threatening pristine seagrass systems. We aim (i) to provide a bench-mark for a near-pristine seagrass system in an archipelago in East Kalimantan, by quantifying a large spectrum of abiotic and biotic properties in seagrass meadows and (ii) to identify early warning indicators for river sediment and nutrient loading, by comparing the seagrass meadow properties over a gradient with varying river influence. Abiotic properties of water column, pore water and sediment were less suitable indicators for increased sediment and nutrient loading than seagrass properties. Seagrass meadows strongly responded to higher sediment and nutrient loads and proximity to the coast by decreasing seagrass cover, standing stock, number of seagrass species, changing species composition and shifts in tissue contents. Our study confirms that nutrient loads are more important than water nutrient concentrations. We identify seagrass system variables that are suitable indicators for sediment and nutrient loading, also in rapid survey scenarios with once-only measurements.  相似文献   
116.
In 2011, northern fulmars (Fulmarus glacialis) from Iceland were used to test the hypothesis that plastic debris decreases at northern latitudes in the Atlantic when moving away from major human centres of coastal and marine activities. Stomach analyses of Icelandic fulmars confirm that plastic pollution levels in the North Atlantic tend to decrease towards higher latitudes. Levels of pollution thus appear to link to regions of intense human coastal and marine activities, suggesting substantial current inputs in those areas.  相似文献   
117.
A dual isotope approach based on compound-specific isotope analysis (CSIA) of carbon (C) and chlorine (Cl) was used to identify sources of persistent trichloroethylene (TCE) that caused the shut-down in 1994 of a municipal well in an extensive fractured dolostone aquifer beneath Guelph, Ontario. Several nearby industrial properties have known subsurface TCE contamination; however, only one has created a comprehensive monitoring network in the bedrock. The impacted municipal well and many monitoring wells were sampled for volatile organic compounds (VOCs), inorganic parameters, and CSIA. A wide range in isotope values was observed at the study site. The TCE varies between -35.6‰ and -21.8‰ and from 1.6‰ to 3.2‰ for δ(13) C and δ(37) Cl, respectively. In case of cis-1,2-dichloroethene, the isotope values range between -36.3‰ and -18.9‰ and from 2.4‰ to 4.7‰ for δ(13) C and δ(37) Cl, respectively. The dual isotope approach represented by a plot of δ(13) C vs. δ(37) Cl shows the municipal well samples grouped in a domain clearly separate from all other samples from the property with the comprehensive well network. The CSIA results collected under non-pumping and short-term pumping conditions thus indicate that this particular property, which has been studied intensively for several years, is not a substantial contributor of the TCE presently in the municipal well under non-pumping conditions. This case study demonstrates that CSIA signatures would have been useful much earlier in the quest to examine sources of the TCE in the municipal well if bedrock monitoring wells had been located at several depths beneath each of the potential TCE-contributing properties. Moreover, the CSIA results show that microbial reductive dechlorination of TCE occurs in some parts of the bedrock aquifer. At this site, the use of CSIA for C and Cl in combination with analyses of VOC and redox parameters proved to be important due to the complexity introduced by biodegradation in the complex fractured rock aquifer. It is highly recommended to revisit the study when the municipal well is back into full operation.  相似文献   
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Measuring the amount of pollution is of particular importance in assessing the quality and general condition of an ecosystem. In this paper, some of the results obtained as a consequence of the specific agreement between the Environmental Agency (Consejería de Medio Ambiente, Junta de Andalucía) and the University of Cadiz to assess the environmental condition of the marine bottom and waters are showed. Physical and chemical analyses in water and sediments were undertaken at various sampling sites close to urban and industrial locations. Later on, these results were studied under statistical analysis to reveal any possible relationships between the parameters employed, and to identify any analogous behaviour between the sampling sites. Physical-chemical data revealed that sediments and waters analysed were moderately contaminated and, in addition, no great differences were found between in rising and ebbing tide conditions. Finally, considering only the pollution level, from the cluster analysis of sediments two major groups appear, one of which corresponded to those sites located in the outer bay, and the other to those situated in the inner bay. However, number 6 and 14 sampling sites cannot be associated to those groups due to be related to points with important local discharges.  相似文献   
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