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781.
Abstract: Networks of sites of high importance for conservation of biological diversity are a cornerstone of current conservation strategies but are fixed in space and time. As climate change progresses, substantial shifts in species’ ranges may transform the ecological community that can be supported at a given site. Thus, some species in an existing network may not be protected in the future or may be protected only if they can move to sites that in future provide suitable conditions. We developed an approach to determine appropriate climate‐change adaptation strategies for individual sites within a network that was based on projections of future changes in the relative proportions of emigrants (species for which a site becomes climatically unsuitable), colonists (species for which a site becomes climatically suitable), and persistent species (species able to remain within a site despite the climatic change). Our approach also identifies key regions where additions to a network could enhance its future effectiveness. Using the sub‐Saharan African Important Bird Area (IBA) network as a case study, we found that appropriate conservation strategies for individual sites varied widely across sub‐Saharan Africa, and key regions where new sites could help increase network robustness varied in space and time. Although these results highlight the potential difficulties within any planning framework that seeks to address climate‐change adaptation needs, they demonstrate that such planning frameworks are necessary, if current conservation strategies are to be adapted effectively, and feasible, if applied judiciously.  相似文献   
782.
丁义志 《四川环境》2010,29(4):91-94
根据安康中心城市两个饮用水水源地环境现状调查和水质监测结果,按照国家《地表水环境质量标准》(GB3838-2002),采用比照法进行了环境质量现状评价。同时,针对目前水源地存在的环境问题,提出了法律法规和制度保护措施、组织保障措施、各级水源保护区的工程治理措施,以及相应的生态修复与建设重点工程和管理能力建设重点工程等,对于改善水源地生态环境系统,有效地保证安康市生活饮用水质量和促进区域水资源可持续利用具有一定的指导作用。  相似文献   
783.
Abstract

Biodegradation of endosulfan isomers in soil‐applied and flask‐coated conditions was studied, by an isolated bacterial coculture. The degradation in soil‐applied form was 20–30% slower than in flask‐coated condition. Addition of a biosurfactant, isolated from Bacillus subtilis MTCC 1427, enhanced the rate of biodegradation by 30–45% in both the conditions. It also mobilized the residual endosulfan towards biodegradation, that otherwise remains undegraded.  相似文献   
784.
对目前项目选址环境可行性论证存在的问题进行了初步分析,并从政策规划的相符性、环境容量的允许性、敏感目标的影响性3个方面探讨了项目选址的环境可行性论证。  相似文献   
785.
阐述在建筑施工现场对高压线输电线路防护的重要性,介绍了对高压线的进行防护的切实可行方法.进而减少或避免重大电气事故的发生.  相似文献   
786.
为了获取无组织排放源被测物质在环境中的最高浓度值,公正地判定被测企业排放源对环境中被测物质浓度贡献的大小,监测人员要依据相关标准和技术导则,正确设置监测点位、选择合适监测时间,以确保监测数据的有效性。  相似文献   
787.
韩智勇  刘丹  李启彬  芦垒 《四川环境》2008,27(1):116-119
通过对风水理论中关于选址要素的科学阐述,从自然环境和社会环境两个方面分析了风水选址和垃圾填埋场选址的共通与不同之处,并根据风水理论中“天人合一”的和谐理念,提出了在填埋场选址过程中,应该融入崇尚自然,尊重自然;结合实际,因地制宜;整体系统;以人为本,和谐构建等原则。  相似文献   
788.
Habitat valuation methods are most often developed and used to prioritize candidate lands for conservation. In this study the intent of habitat valuation was to inform the decision-making process for remediation of chemical contaminants on specific lands or surface water bodies. Methods were developed to summarize dimensions of habitat value for six representative aquatic and terrestrial contaminated sites at the East Tennessee Technology Park (ETTP) on the US Department of Energy Oak Ridge Reservation in Oak Ridge, TN, USA. Several general valuation metrics were developed for three broad categories: site use by groups of organisms, site rarity, and use value added from spatial context. Examples of use value metrics are taxa richness, a direct measure of number of species that inhabit an area, complexity of habitat structure, an indirect measure of potential number of species that may use the area, and land use designation, a measure of the length of time that the area will be available for use. Measures of rarity included presence of rare species or communities. Examples of metrics for habitat use value added from spatial context included similarity or complementarity of neighboring habitat patches and presence of habitat corridors. More specific metrics were developed for groups of organisms in contaminated streams, ponds, and terrestrial ecosystems. For each of these metrics, cutoff values for high, medium, and low habitat value were suggested, based on available information on distributions of organisms and landscape features, as well as habitat use information. A companion paper describes the implementation of these habitat valuation metrics and scoring criteria in the remedial investigation for ETTP.  相似文献   
789.
This study examines the impact of contaminated sites on urban property values in Sydney, Nova Scotia, Canada. The property value effects are examined using an inverse distance specification from the property to the site. A hedonic method employing ordinary least-square technique was used for model estimation. The results show that the presence of contaminated sites has had significant negative effect on the value of residential property. This negative effect, however, is largely localized to within few hundred metres of the sites. The total property value loss in urban Sydney from the contaminated sites is estimated to be $CDN 36 million.  相似文献   
790.
Abstract:  Optimization of resource use is necessary for efficient conservation planning. Many reserve-selection algorithms aim to identify representative but inexpensive networks, which may lead to selecting small sites due to their lower costs and collectively higher species richness. Nevertheless, larger sites would be preferable regarding species' long-term persistence. An area-based refinement can be used to overcome this problem. We used a reserve-planning framework in which continuous benefit functions valued representation (numbers of populations), and differential species weights were based on a species' local rarity and threatened status. We introduced a refinement based on the species-area relationship that provides relatively higher values for larger sites. We applied the proposed method to rich fen vegetation in southern Finland. The species-area refinement resulted in a network of significantly larger sites with minor trade-offs with representation (numbers of populations). Giving endangered species higher weights ensured that the trade-off occurred mostly between site size and representation of low-priority species. We recommend using a species-area refinement for practical, maximum-coverage conservation planning.  相似文献   
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