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141.
Throughout interior Alaska (U.S.A.), a gradual warming trend in mean monthly temperatures occurred over the last few decades (approximatlely 2-4 degrees C). The accompanying increases in woody vegetation at many alpine treeline (hereafter treeline) locations provided an opportunity to examine how biotic and abiotic local site conditions interact to control tree establishment patterns during warming. We devised a landscape ecological approach to investigate these relationships at an undisturbed treeline in the Alaska Range. We identified treeline changes between 1953 (aerial photography) and 2005 (satellite imagery) in a geographic information system (GIS) and linked them with corresponding local site conditions derived from digital terrain data, ancillary climate data, and distance to 1953 trees. Logistic regressions enabled us to rank the importance of local site conditions in controlling tree establishment. We discovered a spatial transition in the importance of tree establishment controls. The biotic variable (proximity to 1953 trees) was the most important tree establishment predictor below the upper tree limit, providing evidence of response lags with the abiotic setting and suggesting that tree establishment is rarely in equilibrium with the physical environment or responding directly to warming. Elevation and winter sun exposure were important predictors of tree establishment at the upper tree limit, but proximity to trees persisted as an important tertiary predictor, indicating that tree establishment may achieve equilibrium with the physical environment. However, even here, influences from the biotic variable may obscure unequivocal correlations with the abiotic setting (including temperature). Future treeline expansion will likely be patchy and challenging to predict without considering the spatial variability of influences from biotic and abiotic local site conditions.  相似文献   
142.
Journal of Material Cycles and Waste Management - In this article, we present the results of the composite development obtained from polyurethane (PU), polyvinyl chloride (PVC), and aluminum...  相似文献   
143.
The open space conservation sub-division offers an alternative to large-lot residential sub-divisions often seen as the culprit when urban sprawl transforms rural landscapes. Homes are sited on somewhat smaller lots, preserving natural areas for the local residents who share ownership of these communal areas and assume responsibility for their management. The article focuses on the experiences of residents of 13 relatively new open space communities. The interviews revealed that most of the communities have already confronted conflicting values with respect to natural areas, low resident participation and challenges in accessing appropriate information. While the open space conservation design holds great promise as a tool for innovative approaches to managing residential growth, it also calls for ways to anticipate and assist communities in caring for their local environment. Recommendations are offered for planning professionals based upon the experience of these open space community residents.  相似文献   
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By interpreting disasters as opportunities to initiate the fulfilment of development needs, realise the vulnerability of the affected community and environment, and extend the legacy of relief funds and effort, this paper builds upon the concept linking relief, rehabilitation and development (LRRD) in the sanitation sector. It aims to use a composite of case studies to devise a framework for a semi‐hypothetical scenario to identify critical components and generic processes for a LRRD action plan. The scenario is based on a latrine wetland sanitation system in a Muslim community. Several sub‐frameworks are developed: (i) latrine design; (ii) assessment of human waste treatment; (iii) connective sanitation promotion strategy; and (iv) ecological systems and environmental services for sanitation and development. This scenario illustrates the complex issues involved in LRRD in sanitation work and provides technical notes and references for a legacy plan for disaster relief and development.  相似文献   
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Regional Environmental Change - This paper synthesizes what is known about the physical and biophysical impacts of climate change and their consequences for societies and development under...  相似文献   
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This paper introduces a new methodology for measuring and modeling manufacturers’ environmental performance and the managerial and technological practices that affect it. Facility level licensing data are used to develop indicators based on sector-specific criteria but capable of being analyzed across sectors, at various levels of aggregation. This addresses the problem that environmental performance and determinants tend to be highly context-specific, while modeling and policy interests are often more general. Using Integrated Pollution Control (IPC) information generated EU-wide, this approach should be capable of cross-country extension. The methodology is tested on a sample of Irish facilities in three sectors during 1996–2004. Preliminary results show its usefulness in exploring the determinants of environmental performance at the sector and cross sector levels. Word count = 10,049.  相似文献   
150.
Microarray testing is the recommended first-tier diagnostic test for women who undergo invasive prenatal diagnostic procedures. It is well-established that microarray analysis provides information regarding copy number for changes (or copy number variants, CNVs) that may be below the resolution level of standard chromosome analysis, and that such CNVs are not related to maternal age. What may not be appreciated by ordering providers, however, are the technical differences among laboratories with respect to the established laboratory cutoff values for reporting, the definition of targeted versus nontargeted regions, and how these differences may affect the interpretation and reporting of findings which, in turn, affects counseling and possible follow-up testing of family members. Here, we provide a detailed explanation of these technical factors and clarify how they practically impact diagnostic results.  相似文献   
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