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Industrial ecology (IE) has historically focused on manufacturing but could be applied more broadly, particularly to sectors of the economy not typically considered "dirty." The guest-service sector, for example, has a significant ecological footprint, often in environmentally sensitive areas, and would benefit from an IE perspective. Colorado's Aspen Skiing Company, which hosts 1.3 million skiers annually on 5, 000 acres of skiable terrain, is integrating concepts of energy efficiency, feedback, life-cycle costing, nutrient cycling, renewable energy, ecosystem diversity, local sourcing, and human capital into operations at four ski areas and two hotels. An IE perspective offers the guest service sector a holistic view of its environmental impacts, a big-picture view that is missing from an industry where environmentalism has historically meant "recycling" or end-of-pipe pollution control. Many industrial ecology principles are directly applicable to resorts, but implementers will encounter a host of obstacles cultural, institutional, and economic that express themselves in unique ways in the guest service sector. Written using firsthand experiences from Aspen's ski slopes, restaurants, and a five-star hotel, this article explores what happens when the principles of industrial ecology are applied to the guest service sector, particularly what goes right, and what goes wrong.  相似文献   
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Our article uses a new institutional economics (NIE) framework to explore the role of voluntary industry standards in the development and implementation of environmental supplier-management programs in the computer industry. We examine two different voluntary standards, one for the management of design for environment (DfE) in the semiconductor fabrication equipment sector and the other for assessing the implementation and use of environmental management systems throughout the computer industry supply chain. We compare and contrast the two standards to explain why the former was widely adopted and has helped integrate DfE into buyer-supplier relations among adopters, whereas the latter failed to gain acceptance. In line with NIE logic, both standards aimed to lower transaction and customization costs by setting "rules of the game" for interfirm transactions that would help simplify and routinize novel environmental supply-chain programs and activities. Their differential success can be elucidated in terms of how well each met the NIE criteria for remediableness and legitimacy. We conclude that voluntary standards have the potential to play an important role in promoting DfE in industrial supply chains. We further conclude that NIE provides a conceptual framework of great value to industrial ecologists who analyze how industry standards and other institutions help firms move toward more sustainable supply-chain management practices.  相似文献   
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管理措施对人工林土壤质量的影响   总被引:3,自引:0,他引:3  
可持续性生产力是人工林发展的一个关键问题。然而,人工林培育过程中常出现土壤质量退化和人工林生产力下降等问题。管理措施是人工林发展过程中土壤质量变化的一个重要因素,正确的管理措施能够维护和提高林地的土壤质量。管理措施主要包括整地、施肥、林地收获与凋落物管理和营造混交林等。不同的整地方式、整地强度、整地时间等能改变土壤物理、化学和生物学性状,进而对其土壤质量产生一定的影响;施肥措施能改善土壤质量、提高人工林生产力,而过量施肥能够导致林地养分的流失和地下水质的恶化;木材收获和林地凋落物焚烧导致人工林系统养分的大量流失,加强对人工林系统有机物质的保护有利于林地土壤质量的改善;营造混交林在一定程度上有利于土壤质量维护,由于物种间存在复杂的相互关系,其对混交树种、混交方式和立地条件的选择等管理措施均能影响土壤质量。最后,文章对今后人工林管理措施对土壤质量影响的重点研究方向作了展望。  相似文献   
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Question: Is the diverse mosaic of forest/grassland (Campos) vegetation on the hills in the Porto Alegre region natural or of anthropogenic origin? What are the best approaches to management and conservation of forest/grassland mosaics in southern Brazil? Location: 280 m a.s.l., Rio Grande do Sul State (30°04′32″S; 51°06′05″W, southern Brazil. Methods: A 50-cm long radiocarbon dated sediment core from a swamp on Morro Santana was analysed for pollen and charcoal, and multivariate data analysis was used to reconstruct past vegetation and fire dynamics. Results: The formation of swamp deposits is related to a change to wetter climatic conditions since 1230 cal yr BP. The diverse forest/grassland mosaic existed already at that time and can be seen as natural in origin as it has been also shown from other studies in southern Brazil. Since 580 cal yr BP, forests expanded continuously. The marked higher occurrence of the pioneer Myrsine during the last 70 years, indicates a change in the disturbance regime. In the past, vegetation has been influenced by mostly anthropogenic fire, set first by Amerindians and later by European settlers. Conclusions: Management for conservation of forest/grassland mosaics should take into account, first, that grasslands are remnants of earlier drier Holocene periods and not a result of deforestation and, second, the history of disturbance by grazing and fire. Suppression of grazing and burning has likely resulted in a trend towards more woody vegetation under modern wet climatic conditions. If management for conservation excludes fire, the present grassland patches will tend to disappear due to forest expansion under the modern humid climate. Maintaining or reintroducing cattle grazing in conservation areas could be an alternative to fire.  相似文献   
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This article presents an integrative approach to calculating the weight of potential biowaste and collected biowaste materials, as the basis for a life‐cycle assessment (LCA) of biowaste management. Biowaste contains kitchen and garden (yard) waste of households. This approach could be used for waste management planning and for the implementation of biowaste schemes. Case studies and examples in the literature are analyzed to model the mass of the flow of biowaste. This article defines relevant operands, presents the main assumptions, and describes the calculation principles. Spatial aspects and the uncertainties related to the inclusion of this aspect are explicitly considered in the calculation of the weight of the potential biowaste. We also present the calculation principles for obtaining the weight of (1) biowaste used in home composting, (2) the organic portion of residual waste, (3) biowaste separately collected by a bring system, and (4) biowaste separately collected by curbside collection (known in some areas as kerbside collection). By choosing the biowaste potential in kilograms per capita year (kg/cap yr) as the functional unit, previously ignored options within the biowaste system could be assessed. For example, widening the system boundaries allows LCA studies to assess the contribution of private and public transport of waste to ecological impact categories. It allows examining the effects of supporting home composting through financial incentives and the introduction of a separate collection system. This study focuses on the comparison of different collection types and on the characteristics of the area under investigation. It also incorporates the behavior of the inhabitants of households and includes a sensitivity analysis of relevant operands. This approach is being included in an LCA assessing biowaste management options.  相似文献   
1000.
Abstract:  Current recommendations to delay the evolution of resistance to Bacillus thuringiensis crops are that a minimum of 5–50% of a crop-growing region should include non- B. thuringiensis varieties as refuges. These recommendations are based in part on the assumption that resistance will be inherited as a recessive trait. Laboratory microcosm experiments are described with transgenic canola expressing Cry1Ac and a non-recessive Cry1Ac resistant population of the diamondback moth Plutella xylostella , in which the effect of different sizes of refugia (0%, 20% and 50%) on resistance was compared over five generations. The LC50 values for Cry1Ac increased markedly in the P. xylostella sub-populations with 0% (>100-fold) and 20% refugia (>35-fold) but showed little change (less than fivefold increase) with 50% refugia. The results support the idea that relatively high levels of refugia (non- B. thuringiensis varieties) may be required where resistance is not functionally recessive at the level of toxin expressed in the B. thuringiensis crop.  相似文献   
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