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631.
在"一带一路"建设中加强资源环境保护工作,不仅适应全球可持续发展的共识,更是我国发挥绿色引领作用的体现,助力构建共同繁荣区域大合作的关键和保障。文章以乌兹别克斯坦为例,基于对该国的实地调研,分析研究其资源环境特点及管理体制对推进"一带一路"的可能影响,提出了我国在"一带一路"建设过程中加强资源环境保护工作的几点建议。  相似文献   
632.
我国大陆地区电器电子产品报废量预测研究   总被引:7,自引:1,他引:6  
随着我国电器电子产品的报废量不断增长,准确预测报废量及其分布对回收网络体系规划研究十分关键.本文利用Gompertz模型及保有量系数法对我国电器电子产品报废量进行建模,在验证预测模型及结果准确性的前提下,对全国31个省2003—2020年电视机、电冰箱、洗衣机、空调及电脑的报废量进行预测,并对5种家用电器报废总量构成、时间序列及空间分布进行分析.结果表明,到2020年,我国5种家用电器报废量将达到20.3亿台,广东省以1794万台报废量列居全国首位,上海市以1083台·km~(-2)的报废密度列居首位;按现有回收处理规模,2014年全国仍存在103万t待处理缺口.最后对废旧电器电子产品拆解处理产能布局提出了合理化建议,为我国的家用电器回收网络规划提供参考.  相似文献   
633.
Abstract: The current shortfall in effectiveness within conservation biology is illustrated by increasing interest in “evidence‐based conservation,” whose proponents have identified the need to benchmark conservation initiatives against actions that lead to proven positive effects. The effectiveness of conservation policies, approaches, and evaluation is under increasing scrutiny, and in these areas models of excellence used in business could prove valuable. Typically, conservation programs require years of effort and involve rigorous long‐term implementation processes. Successful balance of long‐term efforts alongside the achievement of short‐term goals is often compromised by management or budgetary constraints, a situation also common in commercial businesses. “Business excellence” is an approach many companies have used over the past 20 years to ensure continued success. Various business excellence evaluations have been promoted that include concepts that could be adapted and applied in conservation programs. We describe a conservation excellence model that shows how scientific processes and results can be aligned with financial and organizational measures of success. We applied the model to two well‐documented species conservation programs. In the first, the Po’ouli program, several aspects of improvement were identified, such as more authority for decision making in the field and better integration of habitat management and population recovery processes. The second example, the black‐footed ferret program, could have benefited from leadership effort to reduce bureaucracy and to encourage use of best‐practice species recovery approaches. The conservation excellence model enables greater clarity in goal setting, more‐effective identification of job roles within programs, better links between technical approaches and measures of biological success, and more‐effective use of resources. The model could improve evaluation of a conservation program's effectiveness and may be used to compare different programs, for example during reviews of project performance by sponsoring organizations.  相似文献   
634.
Establishing protected areas, where human activities and land cover changes are restricted, is among the most widely used strategies for biodiversity conservation. This practice is based on the assumption that protected areas buffer species from processes that drive extinction. However, protected areas can maintain biodiversity in the face of climate change and subsequent shifts in distributions have been questioned. We evaluated the degree to which protected areas influenced colonization and extinction patterns of 97 avian species over 20 years in the northeastern United States. We fitted single-visit dynamic occupancy models to data from Breeding Bird Atlases to quantify the magnitude of the effect of drivers of local colonization and extinction (e.g., climate, land cover, and amount of protected area) in heterogeneous landscapes that varied in the amount of area under protection. Colonization and extinction probabilities improved as the amount of protected area increased, but these effects were conditional on landscape context and species characteristics. In this forest-dominated region, benefits of additional land protection were greatest when both forest cover in a grid square and amount of protected area in neighboring grid squares were low. Effects did not vary with species’ migratory habit or conservation status. Increasing the amounts of land protection benefitted the range margins species but not the core range species. The greatest improvements in colonization and extinction rates accrued for forest birds relative to open-habitat or generalist species. Overall, protected areas stemmed extinction more than they promoted colonization. Our results indicate that land protection remains a viable conservation strategy despite changing habitat and climate, as protected areas both reduce the risk of local extinction and facilitate movement into new areas. Our findings suggest conservation in the face of climate change favors creation of new protected areas over enlarging existing ones as the optimal strategy to reduce extinction and provide stepping stones for the greatest number of species.  相似文献   
635.
Parks, waterways, and vegetation enhance the well-being of urbanites and thus warrant consideration in planning and policy-making. It is, however, difficult to assess how land-use change may impact these features and how this in turn may impact well-being. I use a case-study approach to present a framework that combines geospatial and economic valuation techniques to generate indicators of the effects of land-use policies that alter these amenities on community well-being. This framework quantifies the impacts of land-use change on urban environmental amenities in a way that could help communities plan land use so as to maintain well-being as they urbanise.  相似文献   
636.
All U.S. federal agencies administering environmental laws purport to practice adaptive management (AM), but little is known about how they actually implement this conservation tool. A gap between the theory and practice of AM is revealed in judicial decisions reviewing agency adaptive management plans. We analyzed all U.S. federal court opinions published through 1 January 2015 to identify the agency AM practices courts found most deficient. The shortcomings included lack of clear objectives and processes, monitoring thresholds, and defined actions triggered by thresholds. This trio of agency shortcuts around critical, iterative steps characterizes what we call AM‐lite. Passive AM differs from active AM in its relative lack of management interventions through experimental strategies. In contrast, AM‐lite is a distinctive form of passive AM that fails to provide for the iterative steps necessary to learn from management. Courts have developed a sophisticated understanding of AM and often offer instructive rather than merely critical opinions. The role of the judiciary is limited by agency discretion under U.S. administrative law. But courts have overturned some agency AM‐lite practices and insisted on more rigorous analyses to ensure that the promised benefits of structured learning and fine‐tuned management have a reasonable likelihood of occurring. Nonetheless, there remains a mismatch in U.S. administrative law between the flexibility demanded by adaptive management and the legal objectives of transparency, public participation, and finality.  相似文献   
637.
Many of the challenges conservation professionals face can be framed as scale mismatches. The problem of scale mismatch occurs when the planning for and implementation of conservation actions is at a scale that does not reflect the scale of the conservation problem. The challenges in conservation planning related to scale mismatch include ecosystem or ecological process transcendence of governance boundaries; limited availability of fine‐resolution data; lack of operational capacity for implementation; lack of understanding of social‐ecological system components; threats to ecological diversity that operate at diverse spatial and temporal scales; mismatch between funding and the long‐term nature of ecological processes; rate of action implementation that does not reflect the rate of change of the ecological system; lack of appropriate indicators for monitoring activities; and occurrence of ecological change at scales smaller or larger than the scale of implementation or monitoring. Not recognizing and accounting for these challenges when planning for conservation can result in actions that do not address the multiscale nature of conservation problems and that do not achieve conservation objectives. Social networks link organizations and individuals across space and time and determine the scale of conservation actions; thus, an understanding of the social networks associated with conservation planning will help determine the potential for implementing conservation actions at the required scales. Social‐network analyses can be used to explore whether these networks constrain or enable key social processes and how multiple scales of action are linked. Results of network analyses can be used to mitigate scale mismatches in assessing, planning, implementing, and monitoring conservation projects. Discordancia de Escalas, Planificación de la Conservación y el Valor del Análisis de Redes Sociales  相似文献   
638.
Meeting report     
SUMMARY

In many developing countries, the determination of a ranking of investments designed to improve and extend the road system is a commonplace prerequisite of planning for the transport sector as a whole and the road sub-sector within it. A major objective of determining investment priorities is to secure the greatest efficiency in the use of resources allocated to the sector and, for this reason, any system of assigning priorities must rely upon conventional investment appraisal techniques producing quantifiable measures of worth. Exercises of this kind, in which road investments are identified and ranked, are usually undertaken to produce a road sector investment plan. The implementation of such plans is, however, often compromised because of perceived deficiencies with a methodology which places undue reliance on investment appraisal and fails to properly address the issue of public interest and sustainability. This paper attempts to produce a pragmatic set of ground rules which, while mindful of the need to promote economic efficiency, allow for other factors to be embraced in a more holistic methodology.  相似文献   
639.
Protected areas’ chief conservation objectives are to include species within their boundaries and protect them from negative external pressures. Many protected areas are not achieving these goals, perhaps in part due to land development inside and outside protected areas. We conducted spatial analyses to evaluate the ability of Canadian protected areas to mitigate the effects of nearby land development. We investigated correlations of national patterns of land development in and around protected areas and then examined national patterns of roads, urban area, and croplands in protected areas. We calculated the amount of developed land in protected areas and within 25–100 km of protected‐area borders, the density of roads, and extent of urban and cropland area in protected areas. We constructed logistic‐regression models to test whether development in a protected area was associated with landscape and protected‐area characteristics. Land development was far less extensive inside than outside protected areas. However, several protected areas, particularly small southern areas near small urban centers had substantial development inside their boundaries, and nearly half of protected areas had roads. The cumulative extent of development within 50 km of protected areas was the best predictor of the probability of land development in protected areas. Canadian First Nations, industries, government, and nongovernmental organizations are currently planning an unprecedented number of new protected areas. Careful management of areas beyond protected‐area boundaries may prove critical to meeting their long‐term conservation objectives. Desarrollo de Tierras Dentro y Alrededor de Áreas Protegidas en la Frontera Silvestre  相似文献   
640.
A vast number of prioritization schemes have been developed to help conservation navigate tough decisions about the allocation of finite resources. However, the application of quantitative approaches to setting priorities in conservation frequently includes mistakes that can undermine their authors’ intention to be more rigorous and scientific in the way priorities are established and resources allocated. Drawing on well‐established principles of decision science, we highlight 6 mistakes commonly associated with setting priorities for conservation: not acknowledging conservation plans are prioritizations; trying to solve an ill‐defined problem; not prioritizing actions; arbitrariness; hidden value judgments; and not acknowledging risk of failure. We explain these mistakes and offer a path to help conservation planners avoid making the same mistakes in future prioritizations. Seis Errores Comunes en la Definición de Prioridades de Conservación  相似文献   
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