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Article impact statement: Structured decision making can be used to identify an optimal source population for conservation introductions.  相似文献   
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Although deforestation and forest degradation have long been considered the most significant threats to tropical biodiversity, across Southeast Asia (Northeast India, Indochina, Sundaland, Philippines) substantial areas of natural habitat have few wild animals (>1 kg), bar a few hunting‐tolerant species. To document hunting impacts on vertebrate populations regionally, we conducted an extensive literature review, including papers in local journals and reports of governmental and nongovernmental agencies. Evidence from multiple sites indicated animal populations declined precipitously across the region since approximately 1980, and many species are now extirpated from substantial portions of their former ranges. Hunting is by far the greatest immediate threat to the survival of most of the region's endangered vertebrates. Causes of recent overhunting include improved access to forests and markets, improved hunting technology, and escalating demand for wild meat, wildlife‐derived medicinal products, and wild animals as pets. Although hunters often take common species, such as pigs or rats, for their own consumption, they take rarer species opportunistically and sell surplus meat and commercially valuable products. There is also widespread targeted hunting of high‐value species. Consequently, as currently practiced, hunting cannot be considered sustainable anywhere in the region, and in most places enforcement of protected‐area and protected‐species legislation is weak. The international community's focus on cross‐border trade fails to address overexploitation of wildlife because hunting and the sale of wild meat is largely a local issue and most of the harvest is consumed in villages, rural towns, and nearby cities. In addition to improved enforcement, efforts to engage hunters and manage wildlife populations through sustainable hunting practices are urgently needed. Unless there is a step change in efforts to reduce wildlife exploitation to sustainable levels, the region will likely lose most of its iconic species, and many others besides, within the next few years.  相似文献   
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Conservation actions need to be prioritized, often taking into account species’ extinction risk. The International Union for Conservation of Nature (IUCN) Red List provides an accepted, objective framework for the assessment of extinction risk. Assessments based on data collected in the field are the best option, but the field data to base these on are often limited. Information collected through remote sensing can be used in place of field data to inform assessments. Forests are perhaps the best‐studied land‐cover type for use of remote‐sensing data. Using an open‐access 30‐m resolution map of tree cover and its change between 2000 and 2012, we assessed the extent of forest cover and loss within the distributions of 11,186 forest‐dependent amphibians, birds, and mammals worldwide. For 16 species, forest loss resulted in an elevated extinction risk under red‐list criterion A, owing to inferred rapid population declines. This number increased to 23 when data‐deficient species (i.e., those with insufficient information for evaluation) were included. Under red‐list criterion B2, 484 species (855 when data‐deficient species were included) were considered at elevated extinction risk, owing to restricted areas of occupancy resulting from little forest cover remaining within their ranges. The proportion of species of conservation concern would increase by 32.8% for amphibians, 15.1% for birds, and 24.7% for mammals if our suggested uplistings are accepted. Central America, the Northern Andes, Madagascar, the Eastern Arc forests in Africa, and the islands of Southeast Asia are hotspots for these species. Our results illustrate the utility of satellite imagery for global extinction‐risk assessment and measurement of progress toward international environmental agreement targets.  相似文献   
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This paper reports the results of 12 years of hydrological monitoring at the St. Fergus dune system in northeastern Scotland. The site is adjacent to the UK’s largest gas terminal and the dunes are crossed in five places by North Sea gas pipelines which were constructed between 1976 and 1990. These are buried beneath the dune system which was restored after pipeline installation. The dunes include a substantial freshwater wetland which is seasonally flooded and provides an important habitat for waterfowl. The hydrogeology of the site is characterized and the hydrogeological processes that sustain this wetland feature are considered including recent climatic fluctuations.  相似文献   
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Payments for ecosystem or ecological services (PES) are voluntary, often market-based approaches to protecting environmental values. In the rural United States, some landowners receive PES through government led conservation programs, but little is known about their involvement in market based arrangements. We analyzed three examples of market based PES arrangements in northwestern Montana: watershed restoration and craft brewing, niche meat production, and certified timber supplies. We find that intermediaries were working between buyers and sellers in each case to set conditions for transactions and undertake the mechanics of implementation. These findings align with existing conceptualizations of intermediaries as crucial links in PES arrangements, but also suggest that intermediaries for market based PES arrangements are not always facilitators or neutral nongovernmental actors; they may actually be from the private sector and drive the process by serving as buyers. This research contributes to stronger understanding of the possibilities for local market based conservation in the rural West.  相似文献   
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An important development in recent years has been increased interest in retrofitting CO2 capture at existing power plants. In parallel, it has also been suggested that flexible operation of power plants with CO2 capture could be important in at least some jurisdictions. It is likely that retrofitted power plants could have significant ??built-in?? flexibility, but this potential is often not considered in studies of the economic performance of power plants with CO2 capture. This paper makes a contribution to filling this gap by developing methods for first order screening analysis of flexible operation of power plants with CO2 capture and applying them to the case study example of an appropriately integrated retrofit of post-combustion capture at a coal-fired power plant. The quantitative analysis suggests that rich solvent storage could be an attractive option on a short-run basis for some fuel, CO2 and electricity price combinations. Results from first order analysis can then be used to determine which operating modes should (and shouldn??t) be included in further, more detailed design studies.  相似文献   
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