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Marine coastal ecosystems, commonly referred to as blue ecosystems, provide valuable services to society but are under increasing threat worldwide due to a variety of drivers, including eutrophication, development, land-use change, land reclamation, and climate change. Ecological restoration is sometimes necessary to facilitate recovery in coastal ecosystems. Blue restoration (i.e., in marine coastal systems) is a developing field, and projects to date have been small scale and expensive, leading to the perception that restoration may not be economically viable. We conducted a global cost–benefit analysis to determine the net benefits of restoring coral reef, mangrove, saltmarsh, and seagrass ecosystems, where the benefit is defined as the monetary value of ecosystem services. We estimated costs from published restoration case studies and used an adjusted-value-transfer method to assign benefit values to these case studies. Benefit values were estimated as the monetary value provided by ecosystem services of the restored habitats. Benefits outweighed costs (i.e., there were positive net benefits) for restoration of all blue ecosystems. Mean benefit:cost ratios for ecosystem restoration were eight to 10 times higher than prior studies of coral reef and seagrass restoration, most likely due to the more recent lower cost estimates we used. Among ecosystems, saltmarsh had the greatest net benefits followed by mangrove; coral reef and seagrass ecosystems had lower net benefits. In general, restoration in nations with middle incomes had higher (eight times higher in coral reefs and 40 times higher in mangroves) net benefits than those with high incomes. Within an ecosystem type, net benefit varied with restoration technique (coral reef and saltmarsh), ecosystem service produced (mangrove and saltmarsh), and project duration (seagrass). These results challenge the perceptions of the low economic viability of blue restoration and should encourage further targeted investment in this field.  相似文献   
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Environmental Science and Pollution Research - PCB forensic science is the process of identifying the source(s) of polychlorinated biphenyls (PCBs) at a site in the context of a legal proceeding to...  相似文献   
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Three shell variables were deemed to be important in the selection of a shell by the hermit crab Pagurus bernhardus (L.). These were the weight, volume and aperture width of a shell. Each of these variables were used in multiple regressions against crab weight for 25 Littorina littorea and 25 Thais lapillus shells chosen when both shell species were together in a tank, and for a further 25 L. littorea and 25 T. lapillus when the two shell species were separate. Principal component analysis was performed on the four groups of 25 shells selected, and multiple-regression equations were calculated using the principal components as the new variables. It was found that crabs chose a shell of suitable general dimensions rather than solely on the basis of one shell variable. The advantages of using statistical techniques developed in this paper over previous approaches to shell selection are discussed.  相似文献   
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Laccases are multicopper oxidases mainly secreted by filamentous fungi. Producing radical forms from organic substrates, they are involved in numerous reactions leading to the degradation and polymerization of xenobiotics. Our studies have led to a better knowledge of the structural, catalytic and genetic properties of laccases and allowed to develop a strategy for their evolution through genetic engineering. Here, we show that fungal laccases, wild or engineered, may be potent tools to develop bioremediation processes of soils polluted by organic compounds, and assays to assess the ecotoxicological impact of these pollutants on soil fungi.  相似文献   
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