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241.
The consideration of information on social values in conjunction with biological data is critical for achieving both socially acceptable and scientifically defensible conservation planning outcomes. However, the influence of social values on spatial conservation priorities has received limited attention and is poorly understood. We present an approach that incorporates quantitative data on social values for conservation and social preferences for development into spatial conservation planning. We undertook a public participation GIS survey to spatially represent social values and development preferences and used species distribution models for 7 threatened fauna species to represent biological values. These spatially explicit data were simultaneously included in the conservation planning software Zonation to examine how conservation priorities changed with the inclusion of social data. Integrating spatially explicit information about social values and development preferences with biological data produced prioritizations that differed spatially from the solution based on only biological data. However, the integrated solutions protected a similar proportion of the species’ distributions, indicating that Zonation effectively combined the biological and social data to produce socially feasible conservation solutions of approximately equivalent biological value. We were able to identify areas of the landscape where synergies and conflicts between different value sets are likely to occur. Identification of these synergies and conflicts will allow decision makers to target communication strategies to specific areas and ensure effective community engagement and positive conservation outcomes. Integración de Valores Biológicos y Sociales al Priorizar Sitios para la Conservación de la Biodiversidad  相似文献   
242.
The conservation of long-distance migratory birds requires coordination between the multiple countries connected by the movements of these species. The recent expansion of tracking studies is shedding new light on these movements, but much of this information is fragmented and inaccessible to conservation practitioners and policy makers. We synthesized current knowledge on the connectivity established between countries by landbirds and raptors migrating along the African–Eurasian flyway. We reviewed tracking studies to compile migration records for 1229 individual birds, from which we derived 544 migratory links, each link corresponding to a species’ connection between a breeding country in Europe and a nonbreeding country in sub-Saharan Africa. We used these migratory links to analyze trends in knowledge over time and spatial patterns of connectivity per country (across species), per species (across countries), and at the flyway scale (across all countries and all species). The number of tracking studies available increased steadily since 2010 (particularly for landbirds), but the coverage of existing tracking data was highly incomplete. An average of 7.5% of migratory landbird species and 14.6% of raptor species were tracked per country. More data existed from central and western European countries, and it was biased toward larger bodied species. We provide species- and country-level syntheses of the migratory links we identified from the reviewed studies, involving 123 populations of 43 species, migrating between 28 European and 43 African countries. Several countries (e.g., Spain, Poland, Ethiopia, Democratic Republic of Congo) are strategic priorities for future tracking studies to complement existing data, particularly on landbirds. Despite the limitations in existing tracking data, our data and results can inform discussions under 2 key policy instruments at the flyway scale: the African–Eurasian Migratory Landbirds Action Plan and the Memorandum of Understanding on the Conservation of Migratory Birds of Prey in Africa and Eurasia.  相似文献   
243.
This paper presents a spatially explicit bioeconomic analysis of species conservation in agricultural areas. Wild species in fragmented agricultural landscapes are best approached as metapopulations consisting of a finite number of local populations. Economic analysis of species conservation in fragmented habitat needs to deal with metapopulation theory and its theoretical implications. This paper presents a spatially explicit bioeconomic model consisting of a straightforward economic land use model and an applied metapopulation model. This paper demonstrates that multiple equilibria and multiple local optima in metapopulations might lead to nonconvexities in the production possibilities set of agricultural profits and species conservation.  相似文献   
244.
美国环境保护部负责评估超过10 000种化学物质的内分泌活动,而合理的实现评估不能仅仅利用体内化验。因此,使用以特定的内分泌系统为目标测定的体外高通量(HTP)数据提出了化学物质体内化验优先原则。最近聚焦于潜在雌激素化学物质—特别是关于能够激活雌激素受体α(ERα)的化学物质的研究工作大致证实了该方法的可行性。然而,该方法存在一个主要的不确定性,那就是基于哺乳动物(主要是人类)的HTP ER化验的优先级是否能够准确地反映chemical-ERα在非哺乳类物种中潜在的相互作用。这里我们对以下几方面进行了全面分析,包括基于ERs结构属性、体外绑定和ERα反式激活数据的相关信息研究chemical-ERα交互作用的跨物种相似性,以及一系列化学物质对体内雌激素信号通路的影响。总的来说,这种综合分析表明,在哺乳动物系统中具有中度到高度雌激素效能的化学物质在非哺乳类脊椎动物中同样是优先级的化学物质。然而,由于缺乏对可能的ERαorthologues的生物作用的了解,优先级方法在多大程度上能够适用于无脊椎动物是不确定的。进一步比较分析鱼类和爬行动物的体外数据表明基于哺乳类的试验可能不会有效地获取在所有脊椎动物门类中ERα与低亲和力的化学物质的交互作用。
精选自Gerald T. Ankley, Carlie A. LaLone, L. Earl Gray, Daniel L. Villeneuve, Michael W. Hornung. Evaluation of the Scientific Underpinnings for Identifying Estrogenic Chemicals in Non-Mammalian Taxa using Mammalian Test Systems. Environmental Toxicology and Chemistry: Volume 35, Issue 11, pages 2806–2816, November 2016. DOI: 10.1002/etc.3456
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3456/full
  相似文献   
245.
This study investigated changes in diversity of shrub-tree layer, leaf decomposition rates, nutrient release and soil NO fluxes of a Brazilian savanna (cerrado sensu stricto) under N, P and N plus P additions. Simultaneous addition of N and P affected density, dominance, richness and diversity patterns more significantly than addition of N or P separately. Leaf litter decomposition rates increased in P and NP plots but did not differ in N plots in comparison to control plots. N addition increased N mass loss, while the combined addition of N and P resulted in an immobilization of N in leaf litter. Soil NO emissions were also higher when N was applied without P. The results indicate that if the availability of P is not increased proportionally to the availability of N, the losses of N are intensified.  相似文献   
246.
This article develops a decision-making framework for environmental management that integrates technical, economic, political and legal, and ethical decision levels. It attempts to show how these decision levels can be ordained, integrated and interconnected and postulates a hierarchic concentric sphere system that proposes an environmental management model for long-term solutions. This model can be used as a check list for environmental management decision-making and also as a guide for environmental conflict resolution where environmental problems necessitate several levels of decision making. It integrates various environmental ethical positions and evaluates political decisions into a comprehensive, broadly applicable multidisciplinary approach. The objective of this decision-making model is to interconnect into a simplified sequence different levels of environmental management processes in order to account for sustainability, efficacy, efficiency and the acceptability of environmental management processes in the long term. This is done by observing when an environmental problem needs to be solved within a certain sphere of solutions and when it requires wider frameworks, how these can be established and how this process proves that solidarity is the widest and most reasonable sphere.  相似文献   
247.
This paper examines the issue of disproportionate costs of Water Framework Directive (WFD) implementation using public surveys as a means to inform policy and decision making. Public taxpayers are asked their opinion regarding the implementation of the WFD and its costs. Taxpayers are expected to bear a large share of the cost of WFD implementation, be it through national taxation, local water pollution charges or higher market prices for water related goods and services. The paper's main objective is to illustrate the role of stated preference research to elicit public opinions and perceptions towards socially acceptable levels of water quality and public willingness to pay (WTP) for the expected environmental benefits of the WFD. Stated preference research can be used as a way to assess the concept of disproportionate costs to those who are expected to bear a large share of the costs of WFD implementation, and at the same time address the issue of public participation in the WFD. The survey results are used as a public consultation tool to inform policy and decision makers about public willingness and ability to pay for the implementation of the WFD. This measure can be used as one of the benchmarks to define disproportionate costs in a cost-benefit context.  相似文献   
248.
Data collection for economic valuation by using Internet surveys and pre-recruited Internet panels can be associated with severe disadvantages. Problems concerning sample coverage and sample representativeness can be expected. Representation errors may occur since people can choose whether to be part of an Internet panel and subsequently whether they wish to participate in the survey, thereby introducing two elements of potential self-selection. These elements may be correlated with preferences, thus making the respondents a non-random and non-representative sample, ultimately biasing results. This paper analyses a sample used for an Internet contingent valuation method survey eliciting preferences for improvements in water quality of a river. We find that some variables that affect the survey participation decision also affect willingness-to-pay, consequently biasing our welfare estimates. We show how adjusting willingness-to-pay for this bias can be accomplished by using a grouped data model incorporating a correlation parameter to account for selection.  相似文献   
249.
The Lake Champlain Basin in Vermont and New York, USA and Quebec, Canada includes a large lake and watershed with complex management issues. A transboundary comprehensive management plan prepared for the lake includes 11 goals across many issue areas. We developed a choice experiment to examine public preferences for alternative Lake Champlain management scenarios across these issue areas. Five ecosystem attributes (water clarity-algae blooms, public beach closures, land use change, fish consumption advisories and the spread of water chestnut, an invasive plant) were varied across three levels and arrayed into paired comparisons following an orthogonal fractional factorial design. Two thousand questionnaires were distributed to basin residents, each including nine paired comparisons that required trading off two, three or four attributes. Completed surveys yielded 6541 responses which were analyzed using binary logistic regression. The results showed that although water clarity and beach closures were important, safe fish consumption was the strongest predictor of choice. Land use pattern and water chestnut distribution were weaker but also significant predictors, with respondents preferring less land development and preservation of the agricultural landscape. Current management efforts in the Lake Champlain Basin are heavily weighted toward improving water clarity by reducing phosphorus pollution. Our results suggest that safe fish consumption warrants additional management attention. Because choice experiments provide information that is much richer than the simple categorical judgments more commonly used in surveys, they can provide managers with information about tradeoffs that could be used to enhance public support and maximize the social benefits of an ecosystem management program.  相似文献   
250.
Assessing climatic suitability provides a good preliminary estimate of the invasive potential of a species to inform risk assessment. We examined two approaches for bioclimatic modeling for 67 reptile and amphibian species introduced to California and Florida. First, we modeled the worldwide distribution of the biomes found in the introduced range to highlight similar areas worldwide from which invaders might arise. Second, we modeled potentially suitable environments for species based on climatic factors in their native ranges, using three sources of distribution data. Performance of the three datasets and both approaches were compared for each species. Climate match was positively correlated with species establishment success (maximum predicted suitability in the introduced range was more strongly correlated with establishment success than mean suitability). Data assembled from the Global Amphibian Assessment through NatureServe provided the most accurate models for amphibians, while ecoregion data compiled by the World Wide Fund for Nature yielded models which described reptile climatic suitability better than available point-locality data. We present three methods of assigning a climate-match score for use in risk assessment using both the mean and maximum climatic suitabilities. Managers may choose to use different methods depending on the stringency of the assessment and the available data, facilitating higher resolution and accuracy for herpetofaunal risk assessment. Climate-matching has inherent limitations and other factors pertaining to ecological interactions and life-history traits must also be considered for thorough risk assessment. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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