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Paetzold A  Smith M  Warren PH  Maltby L 《Ecology》2011,92(9):1711-1716
Resource subsidies between habitats are common and create the potential for the propagation of environmental impacts across system boundaries. However, recent understanding of the potential for subsidy-mediated cross-system impact propagations is limited and primarily based on passive flows of nutrients and detritus or short-term effects. Here, we assess the effects of sustained alterations in aquatic insect emergence (active subsidy pathway), due to chronic stream pollution, for riparian spiders. The sustained reduction in aquatic insect densities at the polluted reaches resulted in a marked decline in web spider population density and a shift in spider community composition. Our results provide the first evidence that stream pollution can control populations and community structure of terrestrial predators via sustained alterations in aquatic subsidies, emphasizing the role of subtle trophic linkages in the transmission of environmental impacts across ecosystem boundaries.  相似文献   
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The development of new tanning agents and new technologies in the leather sector is required to cope with the increasingly higher environmental pressure on the current tanning materials and processes such as tanning with chromium salts. In this paper, the use of titanium wastes (cuttings) resulting from the process of obtaining highly pure titanium (ingots), for the synthesis of new tanning agent and tanning bovine hides with new tanning agent, as alternative to tanning with chromium salts are investigated. For this purpose, Ti waste and Ti-based tanning agent were characterized for metal content by inductively coupled plasma mass spectrometry (ICP-MS) and chemical analysis; the tanned leather (wet white leather) was characterized by Scanning Electron Microscope/Energy Dispersive Using X-ray (Analysis). SEM/EDX analysis for metal content; Differential scanning calorimetric (DSC), Micro-Hot-Table and standard shrinkage temperature showing a hydrothermal stability (ranged from 75.3 to 77 °C) and chemical analysis showing the leather is tanned and can be processed through the subsequent mechanical operations (splitting, shaving). On the other hand, an analysis of major minor trace substances from Ti-end waste (especially vanadium content) in new tanning agent and wet white leather (not detected) and residue stream was performed and showed that leachability of vanadium is acceptable. The results obtained show that new tanning agent obtained from Ti end waste can be used for tanning bovine hides, as eco-friendly alternative for chrome tanning.  相似文献   
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In regulatory practice, the principle of precaution is hardly linked to the ideal of sustainable development. In this article, we argue that it should be. We argue that sustainable development is the sense of an ethics of co-responsibility, while precaution is the attitude needed to realize this sense. From this perspective, we comment on some regulatory practices within the European context regarding authorization requests for deliberate releases of genetically modified crops and show some problems that are popping up there, for example, the difficulties in interpreting the meaning of harm” (and of benefit”), the symptomatic gap between regulatory rule and political practice. Finally, we suggest that, in order to respond to such problems, precaution should find an appropriate translation in the fields of both research and innovation policy, of authorization policy and of economic policy.  相似文献   
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A methodology for the long-term assessment of prices is designed and applied to the international markets for coal, oil and natural gas and likely price developments between 1990 and 2000 are explored. The coal market will remain competitive, and the long-term price will be determined by the total cost of marginal supply. The oil price will be set, even in the long term, substantially above the competitive level, by those who control the exceptional Middle East resource base. The traditional link between gas and oil prices will erode in the 1990s, and gas will be independently and competively priced by the turn of the century. Resource constraints are not expected to push prices upwards within the time horizon of the study. The relative price of gas will fall over the forecast period, and its market share will increase as a consequence.  相似文献   
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This article examines the economic implications of mining or of not mining manganese nodules and summarizes potential ecological consequences. Apart from possible net economic benefits to certain countries, mining the nodules is not regarded as an economic or strategic necessity. It is concluded that expansion of basic research on oceanfloor ecosystems must be granted high priority. It is in the best interest of developed countries to become signatories of the LOS Convention in order to participate in the development of the regulatory framework and to avoid the antagonism of the international community.  相似文献   
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