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541.
Climate change is expected to cause shifts in species distributions worldwide, threatening their viability due to range reductions and altering their representation in protected areas. Biodiversity hotspots might be particularly vulnerable to climate change because they hold large numbers of species with small ranges which could contract even further as species track their optimal habitat. In this study, we assessed the extent to which climate change could cause distribution shifts in threatened and range-restricted birds in Colombia, a megadiverse region that includes the Tropical Andes and Tumbes-Choco-Magdalena hotspots. To evaluate how climate change might influence species in this region, we developed species distribution models using MAXENT. Species are projected to lose on average between 33 and 43 % of their total range under future climate, and up to 18 species may lose their climatically suitable range completely. Species whose suitable climate is projected to disappear occur in mountainous regions, particularly isolated ranges such as the Sierra Nevada de Santa Marta. Depending on the representation target considered, between 46 and 96 % of the species evaluated may be adequately represented in protected areas. In the future, the fraction of species potentially adequately represented is projected to decline to 30–95 %. Additional protected areas may help to retain representativeness of protected areas, but monitoring of species projected to have the largest potential declines in range size will be necessary to assess the need of implementing active management strategies to counteract the effects of climate change.  相似文献   
542.
Iodine-131 reaches the marine environment through its excretion to the sewer by nuclear medicine patients followed by discharge through coastal and deepwater outfalls. 131I has been detected in macroalgae, which bio-accumulate iodine, growing near the coastal outfall of Cronulla sewage treatment plant (STP) since 1995. During this study, 131I levels in liquid effluent and sludge from three Sydney STPs as well as in macroalgae (Ulva sp. and Ecklonia radiata) growing near their shoreline outfalls were measured. Concentration factors of 176 for Ulva sp. and 526 for E. radiata were derived. Radiation dose rates to marine biota from 131I discharged to coastal waters calculated using the ERICA dose assessment tool were below the ERICA screening level of 10 μGy/hr. Radiation dose rates to humans from immersion in seawater or consumption of Ulva sp. containing 131I were three and two orders of magnitude below the IAEA screening level of 10 μSv/year, respectively.  相似文献   
543.
The concept of ecosystem services is increasingly being used by scientists and policy makers. However, most studies in this area have focussed on factors that regulate ecosystem functions (i.e. the potential to deliver ecosystem services) or the supply of ecosystem services. In contrast, demand for ecosystem services (i.e. the needs of beneficiaries) or understanding of the concept and the relative ranking of different ecosystem services by beneficiaries has received limited attention. The aim of this study was to identify in three European mountain regions the ecosystem services of grassland that different stakeholders identify (which ecosystem services for whom), the relative rankings of these ecosystem services, and how stakeholders perceive the provision of these ecosystem services to be related to agricultural activities. We found differences: (1) between farmers?? perceptions of ecosystem services across regions and (2) within regions, between knowledge of ecosystem services gained by regional experts through education and farmers?? local field-based knowledge. Nevertheless, we identified a common set of ecosystem services that were considered important by stakeholders across the three regions, including soil stability, water quantity and quality, forage quality, conservation of botanical diversity, aesthetics and recreation (for regional experts), and forage quantity and aesthetic (for local farmers). We observed two contrasting stakeholder representations of the effects of agricultural management on ecosystem services delivery, one negative and the other positive (considering low to medium management intensity). These representations were determined by stakeholders?? perceptions of the relationships between soil fertility and biodiversity. Overall, differences in perceptions highlighted in this study show that practitioners, policy makers and researchers should be more explicit in their uses of the ecosystem services concept in order to be correctly understood and to foster improved communication among stakeholders.  相似文献   
544.
Catherine Brown 《Disasters》1999,23(3):234-256
Protracted conflict and violence in Burma have been conducive to the growth of the opium industry, Burma's single financial success in recent years of economic crisis and authoritarian rule. This in turn has fed violence and subsequent humanitarian crisis. This paper argues that the underlying political economy of the conflict has been overlooked, while conflict itself has been treated as a peripheral factor in questions of 'development', and further that the opium dynamic is a vital factor in continued violence and vulnerability for non-combatants in the region. A political economy approach, identifying the beneficiaries of violence, will offer a more holistic and effective approach to the protracted crisis.  相似文献   
545.
546.
To investigate if toxic effects by endosulfan, a commonly used insecticide, are dependent on the breeding condition of an organism, both breeding and non-breeding female western mosquitofish, Gambusia affinis, were exposed to 0.1, 0.5, 1 ppb of endosulfan. After a 5-week exposure period, we examined physical factors such as ovary weight and anal fin length in fish of both reproductive conditions and the size of thyroid follicles in non-breeders. Breeding female fish exposed to endosulfan did not show any significant changes in physical factors, but non-breeding females exposed to endosulfan had a significantly greater ratio of anal fin/ body length and larger thyroid follicles than did control females. These results demonstrate that the response to exposure to environmental contaminants may be dependent upon seasonal reproductive condition.  相似文献   
547.
Plasma‐torch technology has excellent potential for cost‐effective treatment of contaminated soils and other types of buried waste material. This article describes the evolution and basic features of this technology, with emphasis on the non‐transferred plasma arc torch. In addition, selected results from both laboratory experiments and field demonstrations will show how this technology can successfully destroy hazardous/toxic materials and/or stabilize contaminants in situ so they are no longer a threat to human health and the environment. © 2001 John Wiley & Sons, Inc.  相似文献   
548.
A site in mid-western Sweden contaminated with chlorinated solvents originating from a previous dry cleaning facility, was investigated using conventional groundwater analysis combined with compound-specific isotope data of carbon, microbial DNA analysis, and geoelectrical tomography techniques. We show the value of this multidisciplinary approach, as the different results supported each interpretation, and show where natural degradation occurs at the site. The zone where natural degradation occurred was identified in the transition between two geological units, where the change in hydraulic conductivity may have facilitated biofilm formation and microbial activity. This observation was confirmed by all methods and the examination of the impact of geological conditions on the biotransformation process was facilitated by the unique combination of the applied methods. There is thus significant benefit from deploying an extended array of methods for these investigations, with the potential to reduce costs involved in remediation of contaminated sediment and groundwater.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01418-5) contains supplementary material, which is available to authorized users.  相似文献   
549.
This study compares negotiation strategy and outcomes in countries illustrating dignity, face, and honor cultures. Hypotheses predict cultural differences in negotiators' aspirations, use of strategy, and outcomes based on the implications of differences in self‐worth and social structures in dignity, face, and honor cultures. Data were from a face‐to‐face negotiation simulation; participants were intra‐cultural samples from the USA (dignity), China (face), and Qatar (honor). The empirical results provide strong evidence for the predictions concerning the reliance on more competitive negotiation strategies in honor and face cultures relative to dignity cultures in this context of negotiating a new business relationship. The study makes two important theoretical contributions. First, it proposes how and why people in a previously understudied part of the world, that is, the Middle East, use negotiation strategy. Second, it addresses a conundrum in the East Asian literature on negotiation: the theory and research that emphasize the norms of harmony and cooperation in social interaction versus empirical evidence that negotiations in East Asia are highly competitive. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
550.
This paper presents the application of three publicly available biota dose assessment models (the ERICA Tool, R&D128/SP1a and RESRAD-BIOTA) to an assessment of the Drigg coastal sand dunes. Using measured 90Sr, 99Tc, 137Cs, 238Pu, 239+240Pu and 241Am activity concentrations in sand dune soil, activity concentration and dose rate predictions are made for a range of organisms including amphibians, birds, invertebrates, mammals, reptiles, plants and fungi. Predicted biota activity concentrations are compared to measured data where available. The main source of variability in the model predictions is the transfer parameters used and it is concluded that developing the available transfer databases should be a focus of future research effort. The value of taking an informed user approach to investigate the way in which models may be expected to be applied in practice is highlighted and a strategy for the future development of intercomparison exercises is presented.  相似文献   
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