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Establishing IUCN Red List Criteria for Threatened Ecosystems   总被引:1,自引:0,他引:1  
Abstract: The potential for conservation of individual species has been greatly advanced by the International Union for Conservation of Nature's (IUCN) development of objective, repeatable, and transparent criteria for assessing extinction risk that explicitly separate risk assessment from priority setting. At the IV World Conservation Congress in 2008, the process began to develop and implement comparable global standards for ecosystems. A working group established by the IUCN has begun formulating a system of quantitative categories and criteria, analogous to those used for species, for assigning levels of threat to ecosystems at local, regional, and global levels. A final system will require definitions of ecosystems; quantification of ecosystem status; identification of the stages of degradation and loss of ecosystems; proxy measures of risk (criteria); classification thresholds for these criteria; and standardized methods for performing assessments. The system will need to reflect the degree and rate of change in an ecosystem's extent, composition, structure, and function, and have its conceptual roots in ecological theory and empirical research. On the basis of these requirements and the hypothesis that ecosystem risk is a function of the risk of its component species, we propose a set of four criteria: recent declines in distribution or ecological function, historical total loss in distribution or ecological function, small distribution combined with decline, or very small distribution. Most work has focused on terrestrial ecosystems, but comparable thresholds and criteria for freshwater and marine ecosystems are also needed. These are the first steps in an international consultation process that will lead to a unified proposal to be presented at the next World Conservation Congress in 2012.  相似文献   
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Abstract:  The Great Barrier Reef Marine Park, an area almost the size of Japan, has a new network of no-take areas that significantly improves the protection of biodiversity. The new marine park zoning implements, in a quantitative manner, many of the theoretical design principles discussed in the literature. For example, the new network of no-take areas has at least 20% protection per "bioregion," minimum levels of protection for all known habitats and special or unique features, and minimum sizes for no-take areas of at least 10 or 20 km across at the smallest diameter. Overall, more than 33% of the Great Barrier Reef Marine Park is now in no-take areas (previously 4.5%). The steps taken leading to this outcome were to clarify to the interested public why the existing level of protection was inadequate; detail the conservation objectives of establishing new no-take areas; work with relevant and independent experts to define, and contribute to, the best scientific process to deliver on the objectives; describe the biodiversity (e.g., map bioregions); define operational principles needed to achieve the objectives; invite community input on all of the above; gather and layer the data gathered in round-table discussions; report the degree of achievement of principles for various options of no-take areas; and determine how to address negative impacts. Some of the key success factors in this case have global relevance and include focusing initial communication on the problem to be addressed; applying the precautionary principle; using independent experts; facilitating input to decision making; conducting extensive and participatory consultation; having an existing marine park that encompassed much of the ecosystem; having legislative power under federal law; developing high-level support; ensuring agency priority and ownership; and being able to address the issue of displaced fishers.  相似文献   
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Extinction‐risk assessments aim to identify biological diversity features threatened with extinction. Although largely developed at the species level, these assessments have recently been applied at the ecosystem level. In South Africa, national legislation provides for the listing and protection of threatened ecosystems. We assessed how land‐cover mapping and the detail of ecosystem classification affected the results of risk assessments that were based on extent of habitat loss. We tested 3 ecosystem classifications and 4 land‐cover data sets of the Little Karoo region, South Africa. Degraded land (in particular, overgrazed areas) was successfully mapped in just one of the land‐cover data sets. From <3% to 25% of the Little Karoo was classified as threatened, depending on the land‐cover data set and ecosystem classification applied. The full suite of threatened ecosystems on a fine‐scale map was never completely represented within the spatial boundaries of a coarse‐scale map of threatened ecosystems. Our assessments highlight the importance of land‐degradation mapping for the listing of threatened ecosystems. On the basis of our results, we recommend that when budgets are constrained priority be given to generating more‐detailed land‐cover data sets rather than more‐detailed ecosystem classifications for the assessment of threatened ecosystems. El Efecto de la Cobertura Terrestre y el Mapeo de Ecosistemas en la Valoración de Riesgos en los Ecosistemas en Little Karoo, Sudáfrica  相似文献   
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Abstract: Global declines in biodiversity and the widespread degradation of ecosystem services have led to urgent calls to safeguard both. Responses to this urgency include calls to integrate the needs of ecosystem services and biodiversity into the design of conservation interventions. The benefits of such integration are purported to include improvements in the justification and resources available for these interventions. Nevertheless, additional costs and potential trade‐offs remain poorly understood in the design of interventions that seek to conserve biodiversity and ecosystem services. We sought to investigate the synergies and trade‐offs in safeguarding ecosystem services and biodiversity in South Africa's Little Karoo. We used data on three ecosystem services—carbon storage, water recharge, and fodder provision—and data on biodiversity to examine several conservation planning scenarios. First, we investigated the amount of each ecosystem service captured incidentally by a conservation plan to meet targets for biodiversity only while minimizing opportunity costs. We then examined the costs of adding targets for ecosystem services into this conservation plan. Finally, we explored trade‐offs between biodiversity and ecosystem service targets at a fixed cost. At least 30% of each ecosystem service was captured incidentally when all of biodiversity targets were met. By including data on ecosystem services, we increased the amount of services captured by at least 20% for all three services without additional costs. When biodiversity targets were reduced by 8%, an extra 40% of fodder provision and water recharge were obtained and 58% of carbon could be captured for the same cost. The opportunity cost (in terms of forgone production) of safeguarding 100% of the biodiversity targets was about US$500 million. Our results showed that with a small decrease in biodiversity target achievement, substantial gains for the conservation of ecosystem services can be achieved within our biodiversity priority areas for no extra cost.  相似文献   
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Conservation Planning as a Transdisciplinary Process   总被引:1,自引:0,他引:1  
Abstract: Despite substantial growth in the field of conservation planning, the speed and success with which conservation plans are converted into conservation action remains limited. This gap between science and action extends beyond conservation planning into many other applied sciences and has been linked to complexity of current societal problems, compartmentalization of knowledge and management sectors, and limited collaboration between scientists and decision makers. Transdisciplinary approaches have been proposed as a possible way to address these challenges and to bridge the gap between science and action. These approaches move beyond the bridging of disciplines to an approach in which science becomes a social process resolving problems through the participation and mutual learning of stakeholders. We explored the principles of transdisciplinarity, in light of our experiences as conservation‐planning researchers working in South Africa, to better understand what is required to make conservation planning transdisciplinary and therefore more effective. Using the transdisciplinary hierarchy of knowledge (empirical, pragmatic, normative, and purposive), we found that conservation planning has succeeded in integrating many empirical disciplines into the pragmatic stakeholder‐engaged process of strategy development and implementation. Nevertheless, challenges remain in engagement of the social sciences and in understanding the social context of implementation. Farther up this knowledge hierarchy, at the normative and purposive levels, we found that a lack of integrated land‐use planning and policies (normative) and the dominant effect of national values (purposive) that prioritize growth and development limit the effectiveness and relevance of conservation plans. The transdisciplinary hierarchy of knowledge highlighted that we need to move beyond bridging the empirical and pragmatic disciplines into the complex normative world of laws, policies, and planning and become engaged in the purposive processes of decision making, behavior change, and value transfer. Although there are indications of progress in this direction, working at the normative and purposive levels requires time, leadership, resources, skills that are absent in conservation training and practice, and new forms of recognition in systems of scientific reward and funding.  相似文献   
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