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Abstract:  Few attempts have been made to analyze the status of conservation efforts at a continental scale, mainly because of the lack of high-quality data sets at this scale. Given that land management agencies want to prioritize conservation efforts and spend limited resources wisely, we recognized the need to undertake a national gap analysis. We developed the most detailed national vegetation cover map feasible to analyze the degree of representation of ecosystem analysis units (an initial representation of ecosystem types) in the network of conservation lands for the continental United States. We combined The Nature Conservancy's ecoregions with the natural land-cover types of the National Land Cover Data Set and examined the conservation status of each combination. The majority of ecosystem analysis units have a small percentage of their total area residing in lands that are managed to support biodiversity. The median percentage of area conserved on status 1 and 2 lands (highest of four levels of protection) as designated by the Gap Analysis Program for the 554 ecosystem analysis units is 4.0% (SD 18.1%). This finding, which highlights our national conservation deficits, points to the need to address the size and diversity of the conservation estate.  相似文献   

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The Aquatic Conservation Strategy of the Northwest Forest Plan   总被引:5,自引:0,他引:5  
Abstract:  Implemented in 1994, the Aquatic Conservation Strategy of the Northwest Forest Plan was designed to restore and maintain ecological processes for aquatic and riparian area conservation on federal lands in the western portion of the Pacific Northwest. We used decision support models to quantitatively evaluate changes in the condition of selected watersheds. In the approximately 10 years since strategy implementation, watershed condition scores changed modestly, but conditions improved in 64% of 250 sampled watersheds, declined in 28%, and remained relatively the same in 7%. Watersheds that had the largest declines included some where wildfires burned 30–60% of their area. The overall statistical distribution of the condition scores did not change significantly, however. Much of the increase in watershed condition was related to improved riparian conditions. The number of large trees (>51 cm diameter at breast height) increased 2–4%, and there were substantial reductions in tree harvest and other disturbances along streams. Whether such changes will translate into longer-term improvements in aquatic ecosystems across broader landscapes remains to be seen.  相似文献   

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唐山城市湿地生态特征与保育对策   总被引:1,自引:0,他引:1  
论述了作为唐山城市湿地的唐海湿地和南湖湿地在湿地面积、湿地类型、湿地动植物资源等方面的生态特征,提出了把城市湿地的保育纳入城市的整体规划、对城市湿地进行动态监测、建立湿地生物多样性指标评价体系、生态修复技术的应用等保育对策,为我国城市湿地的研究与保护提供借鉴。  相似文献   

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Abstract:  In the first comprehensive reviews since 1969, two high-level reports on the status of U.S. marine ecosystems and resources have been released: that of the nongovernmental Pew Oceans Commission in 2003 and that of the congressionally mandated U.S. Commission on Ocean Policy in 2004 . Although the two commissions differed in the breadth and depth of their mandates, their findings on the state of our oceans and need for new management approaches are similar, and their major recommendations for science, governance, management and conservation, and education echo and reinforce each other. The history behind the two commissions and the structure and objectives of each remind us of the crucial roles conservation practitioners and scientists must play in the implementation of report recommendations. The reports suggest priorities for conservation practitioners to improve science, management, conservation, governance, and education to better manage and protect ocean resources and ecosystems. To redirect activities affecting the state of global marine resources, integrated research; education and outreach by terrestrial, aquatic, and marine conservation practitioners; and a clear definition of their roles in the implementation of recommendations is essential. Marine ecosystems provide a test case of society's ability to manage complexity in human and natural systems in an integrated manner, with extensive opportunities for participation by conservation practitioners from all disciplines.  相似文献   

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Abstract:  Fire management is increasingly focusing on introducing heterogeneity in burning patterns under the assumption that "pyrodiversity begets biodiversity." This concept has been formalized as patch mosaic burning (PMB), in which fire is manipulated to create a mosaic of patches representative of a range of fire histories to generate heterogeneity across space and time. Although PMB is an intuitively appealing concept, it has received little critical analysis. Thus we examined ecosystems where PMB has received the most attention and has been the most extensively implemented: tropical and subtropical savannas of Australia and Africa. We identified serious shortcomings of PMB: the ecological significance of different burning patterns remains unknown and details of desired fire mosaics remain unspecified. This has led to fire-management plans based on pyrodiversity rhetoric that lacks substance in terms of operational guidelines and capacity for meaningful evaluation. We also suggest that not all fire patterns are ecologically meaningful: this seems particularly true for the highly fire-prone savannas of Australia and South Africa. We argue that biodiversity-needs-pyrodiversity advocacy needs to be replaced with a more critical consideration of the levels of pyrodiversity needed for biodiversity and greater attention to operational guidelines for its implementation.  相似文献   

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Conservation of the Marbled Murrelet under the Northwest Forest Plan   总被引:1,自引:0,他引:1  
Abstract:  The Marbled Murrelet ( Brachyramphus marmoratus ) was listed as threatened in 1992, primarily because of loss of its old-forest nesting habitat. Monitoring conducted over the first 10 years following implementation of the Northwest Forest Plan shows at-sea murrelet populations appear to be stationary, but recruitment is very low and demographic models project a 4–6% annual rate of decline. Monitoring of nesting habitat indicated there were about 1.6 million ha of higher-suitability nesting habitat on all lands at the start of the plan, about half of which occurred on federal lands. Most (88%) of higher-suitability habitat on federal lands was protected within reserves. Over the past 10 years, losses of habitat due primarily to fire have totaled about 2% on federal lands. Losses have been much greater (12%) on nonfederal lands, due primarily to timber harvest. Habitat is expected to accrue within reserves as younger forest matures and attains sufficient diameter to support nesting sites. At-sea estimates of population size are strongly and positively correlated with amounts of adjacent nesting habitat at a broad scale, supporting the idea that amounts of nesting habitat are a primary driver in wide-scale murrelet population distribution. Conditions at sea, however, such as temperature regimes, prey availability, and pollutants, continue to affect murrelet populations. The system of large reserves seems to have achieved the short-term objective of conserving much of the remaining nesting habitat on federal lands. These reserves are also likely to contribute to the long-term objective of creating large, contiguous blocks of nesting habitat. The plan has a primary role in conserving and restoring nesting habitat on federal land but will succeed in this role only if land allocations calling for such protection are in place for many decades.  相似文献   

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Abstract:  To be relevant to societal interests and needs, conservation science must explicitly lend itself to solving real-world problems. Failure to evaluate under field conditions how a new technology or method performs or the cost of its implementation can prevent its acceptance by end users. Demonstration, defined here as the translation of scientific understanding into metrics of performance and cost of implementation under real-world conditions, is a logical step in the challenging progression from fundamental research to application. Demonstration reduces scientific uncertainty and validates the hypothesis that a management approach is both effective and financially sustainable. Much like adaptive management, demonstration enables researchers and resource managers to avoid trial-and-error approaches and instead conduct unbiased assessment of management interventions. The participation of end users and regulators in the development and execution of demonstration projects ensures that performance measures are credible and increases the probability that successful innovations will be adopted. Four actions might better connect science to the needs of resource managers via demonstration. First, we recommend that demonstration be conducted as a formal process that documents successes and failures. Second, demonstration should be budgeted as an integral component of government agencies' science programs and executed as a partnership between researchers and managers. Third, public and private funders should increase the opportunities and incentives for academics to engage in demonstration. Fourth, social influences on adoption of new technologies and methods should be further explored. When end users can evaluate explicitly whether a new approach is likely to achieve management objectives, save money, and reduce risk under uncertainty, the professional community successfully has bridged a chasm between research and application .  相似文献   

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Gaps and Mismatches between Global Conservation Priorities and Spending   总被引:1,自引:0,他引:1  
Abstract:  Several international conservation organizations have recently produced global priority maps to guide conservation activities and spending in their own and other conservation organizations. Surprisingly, it is not possible to directly evaluate the relationship between priorities and spending within a given organization because none of the organizations with global priority models tracks how they spend their money relative to their priorities. We were able, however, to evaluate the spending patterns of five other large biodiversity conservation organizations without their own published global priority models and investigate the potential influence of priority models on this spending. On average, countries with priority areas received greater conservation investment; global prioritization systems, however, explained between only 2 and 32% of the US$1.5 billion spent in 2002, depending on whether the United States was removed from analyses and whether conservation spending was adjusted by the per capita gross domestic product within each country. We also found little overlap in the spending patterns of the five conservation organizations evaluated, suggesting that informal coordination or segregation of effort may be occurring. Our results also highlight a number of potential gaps and mismatches in how limited conservation funds are spent and provide the first audit of global conservation spending patterns. More explicit presentation of conservation priorities by organizations currently without priority models and better tracking of spending by those with published priorities are clearly needed to help make future conservation activities as efficient as possible.  相似文献   

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Abstract:  Conservation management is becoming increasingly resource intensive as threats to biodiversity grow through habitat destruction, habitat disturbance, and overexploitation. To achieve successful conservation and sustainable use of natural resources, we need to scientifically evaluate the effectiveness of conservation interventions and provide an efficient framework through which scientific evidence can be used to support decision making in policy and practice. We conducted the first formal assessment of the extent to which scientific evidence is used in conservation management through a questionnaire survey and follow-up interviews of compilers of protected-area management plans from major conservation organizations within the United Kingdom and Australia. Our survey results show that scientific information is not being used systematically to support decision making largely because it is not easily accessible to decision makers. This, in combination with limited monitoring and evaluation of effectiveness of management interventions, results in the majority of decisions being based on experience rather than on evidence. To address this problem we propose using an evidence-based framework adapted from that used in the health services and explain how we are currently putting an equivalent framework into practice by establishing review and dissemination units to serve the conservation sector.  相似文献   

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Abstract:  Wildlife populations in small, isolated reserves face genetic and demographic threats to their survival. To increase the probability of long-term persistence, biologists promote metapopulation management, in which breeding subpopulations are protected as source pools. Animals that disperse from the source pools increase the probability of persistence of the metapopulation across the greater landscape. We used a geographic information system (GIS)–based, cost-distance model to design a conservation landscape along the Himalayan foothills for managing a metapopulation of Asia's largest predator, the tiger ( Panthera tigris ). The model is based on data from 30 years of field research on tigers, recent satellite imagery, and a decade of buffer-zone restoration in this region. We used the model to (1) identify potential dispersal corridors for tigers; (2) identify strategic transit refuges; and (3) make recommendations for off-reserve land management and restoration to enhance the potential of corridors for tigers. This tool can aid the design of conservation landscapes for other endangered, wide-ranging species in human-dominated environments.  相似文献   

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When Agendas Collide: Human Welfare and Biological Conservation   总被引:3,自引:0,他引:3  
Abstract:  Conservation should benefit ecosystems, nonhuman organisms, and current and future human beings. Nevertheless, tension among these goals engenders potential ethical conflicts: conservationists' true motivations may differ from the justifications they offer for their activities, and conservation projects have the potential to disempower and oppress people. We reviewed the promise and deficiencies of integrating social, economic, and biological concerns into conservation, focusing on research in ecosystem services and efforts in community-based conservation. Despite much progress, neither paradigm provides a silver bullet for conservation's most pressing problems, and both require additional thought and modification to become maximally effective. We conclude that the following strategies are needed to make conservation more effective in our human-dominated world. (1) Conservation research needs to integrate with social scholarship in a more sophisticated manner. (2) Conservation must be informed by a detailed understanding of the spatial, temporal, and social distributions of costs and benefits of conservation efforts. Strategies should reflect this understanding, particularly by equitably distributing conservation's costs. (3) We must better acknowledge the social concerns that accompany biodiversity conservation; accordingly, sometimes we must argue for conservation for biodiversity's sake, not for its direct human benefits.  相似文献   

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Abstract:  Europe is one of the world's most densely populated continents and has a long history of human-dominated land- and seascapes. Europe is also at the forefront of developing and implementing multinational conservation efforts. In this contribution, we describe some top policy issues in Europe that need to be informed by high-quality conservation science. These include evaluation of the effectiveness of the Natura 2000 network of protected sites, implications of rapid economic and subsequent land-use change in Central and Eastern Europe, conservation of marine biodiversity and sustainability of fisheries, the effect of climate change on movement of species in highly fragmented landscapes, and attempts to assess the economic value of ecosystem services and biodiversity. Broad policy issues such as those identified are not easily amenable to scientific experiment. A key challenge at the science–policy interface is to identify the research questions underlying these problem areas so that conservation science can provide evidence to underpin future policy development .  相似文献   

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Rethinking Community-Based Conservation   总被引:34,自引:0,他引:34  
Abstract:  Community-based conservation (CBC) is based on the idea that if conservation and development could be simultaneously achieved, then the interests of both could be served. It has been controversial because community development objectives are not necessarily consistent with conservation objectives in a given case. I examined CBC from two angles. First, CBC can be seen in the context of paradigm shifts in ecology and applied ecology. I identified three conceptual shifts—toward a systems view, toward the inclusion of humans in the ecosystem, and toward participatory approaches to ecosystem management—that are interrelated and pertain to an understanding of ecosystems as complex adaptive systems in which humans are an integral part. Second, I investigated the feasibility of CBC, as informed by a number of emerging interdisciplinary fields that have been pursuing various aspects of coupled systems of humans and nature. These fields—common property, traditional ecological knowledge, environmental ethics, political ecology, and environmental history—provide insights for CBC. They may contribute to the development of an interdisciplinary conservation science with a more sophisticated understanding of social-ecological interactions. The lessons from these fields include the importance of cross-scale conservation, adaptive comanagement, the question of incentives and multiple stakeholders, the use of traditional ecological knowledge, and development of a cross-cultural conservation ethic.  相似文献   

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A Freshwater Classification Approach for Biodiversity Conservation Planning   总被引:8,自引:0,他引:8  
Abstract:  Freshwater biodiversity is highly endangered and faces increasing threats worldwide. To be complete, regional plans that identify critical areas for conservation must capture representative components of freshwater biodiversity as well as rare and endangered species. We present a spatially hierarchical approach to classify freshwater systems to create a coarse filter to capture representative freshwater biodiversity in regional conservation plans. The classification framework has four levels that we described using abiotic factors within a zoogeographic context and mapped in a geographic information system. Methods to classify and map units are flexible and can be automated where high-quality spatial data exist, or can be manually developed where such data are not available. Products include a spatially comprehensive inventory of mapped and classified units that can be used remotely to characterize regional patterns of aquatic ecosystems. We provide examples of classification procedures in data-rich and data-poor regions from the Columbia River Basin in the Pacific Northwest of North America and the upper Paraguay River in central South America. The approach, which has been applied in North, Central, and South America, provides a relatively rapid and pragmatic way to account for representative freshwater biodiversity at scales appropriate to regional assessments.  相似文献   

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自然保护区生态旅游管理规划的基本原则   总被引:6,自引:0,他引:6  
针对在自然保护区发展生态旅游存在许多问题,诸如自然环境破坏、自然资源匮乏、环境污染、生物多样性减少、管理不完善等问题,提出了在自然保护区发展生态旅游的基本原则。  相似文献   

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Abstract:  Over the last decade, 2 major U.S. commissions on ocean policy and a wide range of independent sources have argued that ocean ecosystems are in a period of crisis and that current policies are inadequate to prevent further ecological damage. These sources have advocated ecosystem-based management as an approach to address conservation issues in the oceans, but managers remain uncertain as to how to implement ecosystem-based approaches in the real world. We argue that the philosophies of Edward F. Ricketts, a mid-20th-century marine ecologist, offer a framework and clear guidance for taking an ecosystem approach to marine conservation. Ricketts' philosophies, which were grounded in basic observations of natural history, espoused building a holistic picture of the natural world, including the influence of humans, through repeated observation. This approach, when applied to conservation, grounds management in what is observable in nature, encourages early action in the face of uncertainty, and supports an adaptive approach to management as new information becomes available. Ricketts' philosophy of "breaking through," which focuses on getting beyond crisis and conflict through honest debate of different parties' needs (rather than forcing compromise of differing positions), emphasizes the social dimension of natural resource management. New observational technologies, long-term ecological data sets, and especially advances in the social sciences made available since Ricketts' time greatly enhance the utility of Ricketts' philosophy of marine conservation.  相似文献   

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