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961.
962.
963.
Some argue that a collective vision for the future of the Laurentian Great Lakes is embodied in the␣Great Lakes Water Quality Agreement (GLWQA). The GLWQA is a binational agreement, first signed in 1972 by Prime Minister Pierre Trudeau and President Richard Nixon, wherein the two countries (the Parties) commit to “restore and maintain the chemical, physical and biological integrity of the waters of the Great Lakes Basin Ecosystem.” Article X of the Agreement states that the Parties shall conduct a comprehensive review of the operation and effectiveness of this Agreement following every third biennial report of the [International Joint] Commission (IJC). The IJC’s 12th Biennial Report, released in 2004, triggered this important science, program, and policy review which commenced May 2006. This essay makes the case for a rigorous review, that explores deliberately the future scope of the Agreement to protect the world’s largest surface freshwater resource, and calls for innovation in the governance regime of this binational ecosystem.  相似文献   
964.
965.
Successful biodiversity conservation does not depend on ecologic knowledge alone. Good conservation policies and policy implementation tools are equally important. Moreover, the knowledge, skills, and attitudes of local actors, directly in charge of operations in the field, are a key to successful policy implementation. The connections between policy objectives and their implementation as well as the involvement of local actors’ efforts in implementing policy objectives largely depend on the governance model in use. This article assesses the knowledge of local actors in relation to the biodiversity conservation objectives and tools in Lithuanian forest management. As a main framework for this study, the needs assessment approach was applied. The study used both in-depth open-ended interviews and follow-up telephone interviews. Two state forest enterprises in Lithuania were selected as the study sites. The findings indicate that policy objectives in the field of forest biodiversity conservation and the related tools are well known but not well understood by those in charge of forest biodiversity policy implementation. To improve the situation, a transition toward adaptive learning and participatory governance as a means of facilitating conservation efforts is proposed.  相似文献   
966.
Advocates of community-based approaches to environmental management argue that by respecting local circumstances, skills, and concerns we may improve the prospects of achieving environmental sustainability; yet, within nation states such as Canada, environmental conditions, management and enforcement costs and capabilities, and power differentials within and among civic and public sectors may result in a highly differentiated capacity for environmental management across different localities and regions. This article draws on insights of political ecology to 1) create a conceptual framework that identifies key elements shaping regional environmental management regimes and to 2) undertake a comparative analysis to assess how elements interact to generate uneven management outcomes. I compare experiences of two Canadian biosphere reserves designated in 2000: Clayoquot Sound, BC; and Redberry Lake, SK. Analysis reveals that differences in governance and institutional capacities in the biosphere reserves are key to explaining uneven local outcomes. Where the public and civic sectors are strong, a robust and publicly vetted form of management will emerge. Where these sectors are weak and land is held as private property, environmental nongovernmental organizations can set the type and level of management, to the exclusion of effective civic and state involvement. This result may improve environmental sustainability but hinder social sustainability of a management regime and raises questions about the efficacy of community-based management.  相似文献   
967.
Cost-efficient sample designs for collection of ground data and accurate mapping of variables are required to monitor natural resources and environmental and ecological systems. In this study, a sample design and mapping method was developed by integrating stratification, model updating, and cokriging with Landsat Thematic Mapper (TM) imagery. This method is based on the spatial autocorrelation of variables and the spatial cross-correlation among them. It can lead to sample designs with variable grid spacing, where sampling distances between plots vary depending on spatial variability of the variables from location to location. This has potential cost-efficiencies in terms of sample design and mapping. This method is also applicable for mapping in the case in which no ground data can be collected in some parts of a study area because of the high cost. The method was validated in a case study in which a ground and vegetation cover factor was sampled and mapped for monitoring soil erosion. The results showed that when the sample obtained with three strata using the developed method was used for sampling and mapping the cover factor, the sampling cost was greatly decreased, although the error of the map was slightly increased compared to that without stratification; that is, the sample cost-efficiency quantified by the product of cost and error was greatly increased. The increase of cost-efficiency was more obvious when the cover factor values of the plots within the no-significant-change stratum were updated by a model developed using the previous observations instead of remeasuring them in the field.  相似文献   
968.
It has traditionally been argued that recycling municipal solid waste (MSW) is usually not economically viable and that only when externalities, long-term dynamic considerations, and/or the entire product life cycle are taken into account, recycling becomes worthwhile from a social point of view. This article explores the results of a wide study conducted in Israel in the years 2000–2004. Our results reveal that recycling is optimal more often than usually claimed, even when externality considerations are ignored. The study is unique in the tools it uses to explore the efficiency of recycling: a computer-based simulation applied to an extensive database. We developed a simulation for assessing the costs of handling and treating MSW under different waste-management systems and used this simulation to explore possible cost reductions obtained by designating some of the waste (otherwise sent to landfill) to recycling. We ran the simulation on data from 79 municipalities in Israel that produce over 60% of MSW in Israel. For each municipality, we were able to arrive at an optimal method of waste management and compare the costs associated with 100% landfilling to the costs born by the municipality when some of the waste is recycled. Our results indicate that for 51% of the municipalities, it would be efficient to adopt recycling, even without accounting for externality costs. We found that by adopting recycling, municipalities would be able to reduce direct costs by an average of 11%. Through interviews conducted with representatives of municipalities, we were also able to identify obstacles to the utilization of recycling, answering in part the question of why actual recycling levels in Israel are lower than our model predicts they should be.  相似文献   
969.
Although the importance of understanding stakeholder beliefs regarding environmental policy has been noted by many authors, research focusing on the heterogeneity of stakeholder views is still very scarce and concentrated on a product-oriented definition of stakeholders. The aim of the present study is to address this gap by examining environmental policy beliefs of stakeholder groups engaged in protected area management. Questionnaires containing 73 five-point Likert scale items were administered to eight different stakeholder groups involved in the management of Greek protected areas. Items referred to core beliefs on environmental policy, namely, the value framework and sustainable development, and secondary beliefs, that is, beliefs on social consensus and ecotourism development. Our study used as a starting point respondent recruitment on the basis of a traditional product-centered approach. We investigated whether environmental policy beliefs can be used to effectively segregate stakeholders in well-defined segments, which override the product-oriented definition of stakeholders. Indeed, K-means clustering revealed an innovation-introduction and an implementation-charged sample segment. The instrument utilized in this research proved quite reliable and valid in measuring stakeholder environmental policy beliefs. Furthermore, the methodology implied that stakeholder groups differ in a significant number of belief-system elements. On the other hand, stakeholder groups were effectively distinguished on a small set of both core and secondary beliefs. Therefore, the instrument used can be an effective tool for determining and monitoring environmental policy beliefs of stakeholders in protected area management. This is of considerable importance in the Greek case, given the recent establishment of 27 administrative bodies of protected areas, all of which are required to incorporate public consultation into management practices.  相似文献   
970.
Many problems and challenges of ecosystem management currently are driven by the rapid pace and spatial extent of landscape change. Parks and reserves within areas of high human population density are especially challenged to meet the recreational needs of local populations and to preserve valued environmental resources. The complex problem of managing multiple objectives and multiple resources requires an enormous quantity of information, and conceptual models have been proposed as tools for organizing and interpreting this information. Academics generally prefer a bottom-up approach to model construction that emphasizes ecologic theory and process, whereas managers often use a top-down approach that takes advantage of existing information to address more pragmatic objectives. The authors propose a formal process for developing, applying, and testing conceptual models to be used in landscape monitoring that reconciles these seemingly opposing perspectives. The four-step process embraces the role of hypothesis testing in the development of models and evaluation of their utility. An example application of the process to a network of national parks in and around Washington, DC illustrates the ability of the approach to systematically identify monitoring data that would both advance ecologic theory and inform management decisions.  相似文献   
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