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531.
The French government has launched three separate calls for tender in July 2011, March 2013, and December 2016 to install 3.5 GW of offshore wind. In addition to contributing to the fulfillment of environmental commitments, the deployment of offshore wind energy is expected to be a lever for economic development. To assess gross economic impacts, mainly in terms of job creation, we built a regional input-output model of the wind farm off Saint-Brieuc located in the region of Brittany, north-western France. Our model indicates that the project will have positive effects on Brittany’s economy. In particular, during the investment phase, the wind farm is expected to lead to €0.38 M/year/MW of added value and 6.03 full-time equivalent (FTE) jobs/year/MW. During the operation and maintenance (O&M) phase, the model predicts the generation of €0.15 M/year/MW of added value and 1.02 FTE jobs/year/MW. These results imply that the project will increase Brittany’s GDP slightly by 0.22 and 0.09% during the investment and O&M phases, respectively. Results also show that out of total wealth created in France, 38 and 66% will be created in Brittany as well as 32 and 51% of employment during respectively investment and O&M phases. A comparative analysis highlights in particular that economic impacts are generally stronger during the investment phase. It also demonstrates that the magnitude of economic impacts depends on the proportion of local industries in the supply chain. Policy implications of our model stress the need to revise the economic, technological, regulatory, and social frameworks within which the offshore wind industry currently operates in France to establish the conditions necessary for its development.  相似文献   
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Ultrafine particles represent a growing concern in the public health community but their precise role in many illnesses is still unknown. This lack of knowledge is related to the experimental difficulty in linking their biological effects to their multiple properties, which are important determinants of toxicity. Our aim is to propose an interdisciplinary approach to study fine(FP) and ultrafine(UFP) particles, generated in a controlled manner using a mini CAST(Combustion Aerosol Standard) soot ...  相似文献   
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A monitoring and evaluation program was undertaken, involving six different styles of evaluation to determine whether a low-cost, eight month education campaign that operated within a small commercial district was successful at changing people's behavior and reducing stormwater litter loads. This project also tested newly developed guidelines for monitoring and evaluating all types of non-structural stormwater quality best management practices (BMPs). The project evaluated: the extent and quality of the campaign's implementation; the degree to which it changed the awareness, attitudes, self-reported behavior and actual behavior of merchants and the public; and the nature of changes in stormwater litter loads. Overall, the education campaign produced mixed results, with the net result being modestly positive. Specifically, it was: unsuccessful at significantly influencing the knowledge or attitudes of merchants or the public; modestly successful at influencing the behavior of merchants and the public; and modestly successful at reducing litter loads in stormwater. At a theoretical level, the project highlights how using different 'styles' of BMP evaluation can help to build a more complete picture of a BMP's performance. At a practical level, the project helped to improve the monitoring and evaluation guidelines and produced evidence-based design guidelines for future campaigns that aim to reduce littering in commercial areas.  相似文献   
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Globally, fisheries bycatch threatens the survival of many whale and dolphin species. Strategies for reducing bycatch can be expensive. Management is inclined to prioritize investment in actions that are inexpensive, but these may not be the most effective. We used an economic tool, return-on-investment, to identify cost-effective measures to reduce cetacean bycatch in the trawl, net, and line fisheries of Australia. We examined 3 management actions: spatial closures, acoustic deterrents, and gear modifications. We compared an approach for which the primary goal was to reduce the cost of bycatch reduction to fisheries with an approach that aims solely to protect whale and dolphin species. Based on cost-effectiveness and at a fine spatial resolution, we identified the management strategies across Australia that most effectively abated dolphin and whale bycatch. Although trawl-net modifications were the cheapest strategy overall, there were many locations where spatial closures were the most cost-effective solution, despite their high costs to fisheries, due to their effectiveness in reducing all fisheries interactions. Our method can be used to delineate strategies to reduce bycatch threats to mobile marine species across diverse fisheries at relevant spatial scales to improve conservation outcomes.  相似文献   
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In the context of climate change, this study evaluates the impact on the long-shore and cross-shore sediment transport (LST and CST) along the Catalan coast (NW Mediterranean Sea) derived from climate projections obtained from five combinations of regional and global circulation models (RCMs and GCMs). Special emphasis is given to how inter-model variability translates from wave projections to wave-driven coastal impacts, which is still poorly known. Results show that the uncertainty is in general larger, especially for LST, for which the discrepancies among regional models are more relevant than those associated with the forcing wave parameters. Such increase in the uncertainty can be explained by the nonlinear processes involved, and the role of the forcing wave parameters having sometimes competing effects (e.g. wave height vs. wave direction). This illustrates that the performance of each RCM–GCM can vary from forcing to impact parameters; hence, the suitability of a particular RCM–GCM to evaluate a certain impact should be assessed based on its ability to properly simulate such impact. In this regard, LST and CST rates computed using empirical formulae that integrate several wave climate parameters, as in this study, can be used as a non-computationally expensive tool to assess the suitability of a given RCM–GCM to project changes in coastal dynamics.  相似文献   
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Most hypotheses explaining the general gradient of higher diversity toward the equator are implicit or explicit about greater species packing in the tropics. However, global patterns of diversity within guilds, including trophic guilds (i.e., groups of organisms that use similar food resources), are poorly known. We explored global diversity patterns of a key trophic guild in stream ecosystems, the detritivore shredders. This was motivated by the fundamental ecological role of shredders as decomposers of leaf litter and by some records pointing to low shredder diversity and abundance in the tropics, which contrasts with diversity patterns of most major taxa for which broad-scale latitudinal patterns haven been examined. Given this evidence, we hypothesized that shredders are more abundant and diverse in temperate than in tropical streams, and that this pattern is related to the higher temperatures and lower availability of high-quality leaf litter in the tropics. Our comprehensive global survey (129 stream sites from 14 regions on six continents) corroborated the expected latitudinal pattern and showed that shredder distribution (abundance, diversity and assemblage composition) was explained by a combination of factors, including water temperature (some taxa were restricted to cool waters) and biogeography (some taxa were more diverse in particular biogeographic realms). In contrast to our hypothesis, shredder diversity was unrelated to leaf toughness, but it was inversely related to litter diversity. Our findings markedly contrast with global trends of diversity for most taxa, and with the general rule of higher consumer diversity at higher levels of resource diversity. Moreover, they highlight the emerging role of temperature in understanding global patterns of diversity, which is of great relevance in the face of projected global warming.  相似文献   
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