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181.
Social Capital in Biodiversity Conservation and Management   总被引:8,自引:0,他引:8  
Abstract:  The knowledge and values of local communities are now being acknowledged as valuable for biodiversity conservation. Relationships of trust, reciprocity and exchange, common rules, norms and sanctions, and connectedness in groups are what make up social capital, which is a necessary resource for shaping individual action to achieve positive biodiversity outcomes. Agricultural and rural conservation programs address biodiversity at three levels: agrobiodiversity on farms, nearby nature in landscapes, and protected areas. Recent initiatives that have sought to build social capital have shown that rural people can improve their understanding of biodiversity and agroecological relationships at the same time as they develop new social rules, norms, and institutions. This process of social learning helps new ideas to spread and can lead to positive biodiversity outcomes over large areas. New ideas spread more rapidly where there is high social capital. There remain many practical and policy difficulties, however, not least regarding the need to invest in social capital formation and the many unresolved questions of how the state views communities empowered to make their own decisions. Nonetheless, attention to the value of social relations, in the form of trust, reciprocal arrangements, locally developed rules, norms and sanctions, and emergent institutions, has clearly been shown to deliver a biodiversity dividend in many contexts. This suggests a need to blend both the biological and social elements of conservation.  相似文献   
182.
  总被引:1,自引:0,他引:1  
Intentamos asociar las diferencias entre las poblaclones de fauna en la cuenca de Tensas con las diferencias de extensión de áreas de bosques caducifolios de tierras bajas, usando datos existentes. La cuenca de Tensas era parte del area de distribución original de varias especies que actualmente están ausentes: lobo rojo, la puma de Florida, Pájaro Carpintero. El oso negro de Louisiana y Gorjeador de Bachman. también está en peligro de extinción. Los catastras de aves proporcionaron los mejores datos faunisticos Las comparaciones de poblaciones de aves (1) con la disminución del bosque caducifolio de tierras bajas al pasar del tiempo y (2) con áreas con diferentes superficies de este tipo de bosque apoyan la bipótesis de que el número de especies selvicolas y las densidades de población de especies del interior del bosque decrecieron junto con la disminución acumulativa en el área de bosques. Hemos señalado el deterioro de las poblaciones de fauna autoctona utilizando encuestas existentes de aves y datos cualitativos, demostrando la utilidad del enfoque del impacto acumulativo a una escala de cuencas hidrográfica Asegurando la conservación de los habitats necesarioq un plan de munejo de impacto acumulativo reducería extinciones adicionales en esta cuenca hidrográfica.  相似文献   
183.
Abstract: Funding for conservation is limited, and its investment for maximum conservation gain can likely be enhanced through the application of relevant science. Many donor institutions support and use science to pursue conservation goals, but their activities remain relatively unfamiliar to the conservation‐science community. We examined the priorities and practices of U.S.‐based private foundations that support biodiversity conservation. We surveyed 50 donor members of the Consultative Group on Biological Diversity (CGBD) to address three questions: (1) What support do CGBD members provide for conservation science? (2) How do CGBD members use conservation science in their grant making and strategic thinking? (3) How do CGBD members obtain information about conservation science? The 38 donor institutions that responded to the survey made $340 million in grants for conservation in 2005, including $62 million for conservation science. Individual foundations varied substantially in the proportion of conservation funds allocated to science. Foundations also varied in the ways and degree to which they used conservation science to guide their grant making. Respondents found it “somewhat difficult” to stay informed about conservation science relevant to their work, reporting that they accessed conservation science information mainly through their grantees. Many funders reported concerns about the strategic utility of funding conservation science to achieve conservation gains. To increase investment by private foundations in conservation science, funders, researchers, and conservation practitioners need to jointly identify when and how new scientific knowledge will lower barriers to conservation gains. We envision an evolving relationship between funders and conservation scientists that emphasizes primary research and synthesis motivated by (1) applicability, (2) human‐ecosystem interactions, (3) active engagement among scientists and decision makers, and (4) broader communication of relevant scientific information.  相似文献   
184.
    
Bushmeat markets exist in many countries in West and Central Africa, and data on species sold can be used to detect patterns of wildlife trade in a region. We surveyed 89 markets within the Cross–Sanaga rivers region, West Africa. In each market, we counted the number of carcasses of each taxon sold. During a 6‐month period (7594 market days), 44 mammal species were traded. Thirteen species were on the International Union for Conservation of Nature (IUCN) Red List or protected under national legislation, and at least 1 threatened species was traded in 88 of the 89 markets. We used these data to identify market groups that traded similar species assemblages. Using cluster analyses, we detected 8 market groups that were also geographically distinct. Market groups differed in the diversity of species, evenness of species, and dominant, prevalent, and characteristic species traded. We mapped the distribution of number of threatened species traded across the study region. Most threatened species were sold in markets nearest 2 national parks, Korup National Park in Cameroon and Cross River in Nigeria. To assess whether the threatened‐species trade hotspots coincided with the known ranges of these species, we mapped the overlap of all threatened species traded. Markets selling more threatened species overlapped with those regions that had higher numbers of these. Our study can provide wildlife managers in the region with better tools to discern zones within which to focus policing efforts and reduce threats to species that are threatened by the bushmeat trade. Mapeo de Sitios Críticos para Especies Amenazadas Comercializadas en Mercados de Vida Silvestre en la Región de los Ríos Cross‐Sanaga  相似文献   
185.
Abstract: Because habitat loss due to urbanization is a primary threat to biodiversity, and land‐use decisions in urbanizing areas are mainly made at the local level, land‐use planning by municipal planning departments has a potentially important—but largely unrealized—role in conserving biodiversity. To understand planners’ perspectives on the factors that facilitate and impede biodiversity conservation in local planning, we interviewed directors of 17 municipal planning departments in the greater Seattle (Washington, U.S.A.) area and compared responses of planners from similar‐sized jurisdictions that were “high” and “low performing” with respect to incorporation of biodiversity conservation in local planning. Planners from low‐performing jurisdictions regarded mandates from higher governmental levels as the primary drivers of biodiversity conservation, whereas those from high‐performing jurisdictions regarded community values as the main drivers, although they also indicated that mandates were important. Biodiversity conservation was associated with presence of local conservation flagship elements (e.g., salmonids) and human‐centered benefits of biodiversity conservation (e.g., quality of life). Planners from high‐ and low‐performing jurisdictions favored different planning mechanisms for biodiversity conservation, perhaps reflecting differences in funding and staffing. High performers reported more collaborations with other entities on biodiversity issues. Planners’ comments indicated that the term biodiversity may be problematic in the context of local planning. The action most planners recommended to increase biodiversity conservation in local planning was public education. These results suggest that to advance biodiversity conservation in local land‐use planning, conservation biologists should investigate and educate the public about local conservation flagships and human benefits of local biodiversity, work to raise ecological literacy and explain biodiversity more effectively to the public, and promote collaboration on biodiversity conservation among jurisdictions and inclusion of biodiversity specialists in planning departments.  相似文献   
186.
Abstract: Consideration of the social values people assign to relatively undisturbed native ecosystems is critical for the success of science‐based conservation plans. We used an interview process to identify and map social values assigned to 31 ecosystem services provided by natural areas in an agricultural landscape in southern Australia. We then modeled the spatial distribution of 12 components of ecological value commonly used in setting spatial conservation priorities. We used the analytical hierarchy process to weight these components and used multiattribute utility theory to combine them into a single spatial layer of ecological value. Social values assigned to natural areas were negatively correlated with ecological values overall, but were positively correlated with some components of ecological value. In terms of the spatial distribution of values, people valued protected areas, whereas those natural areas underrepresented in the reserve system were of higher ecological value. The habitats of threatened animal species were assigned both high ecological value and high social value. Only small areas were assigned both high ecological value and high social value in the study area, whereas large areas of high ecological value were of low social value, and vice versa. We used the assigned ecological and social values to identify different conservation strategies (e.g., information sharing, community engagement, incentive payments) that may be effective for specific areas. We suggest that consideration of both ecological and social values in selection of conservation strategies can enhance the success of science‐based conservation planning.  相似文献   
187.
Abstract: The lack of long‐term baseline data restricts the ability to measure changes in biological diversity directly and to determine its cause. This hampers conservation efforts and limits testing of basic tenets of ecology and conservation biology. We used a historical baseline survey to track shifts in the abundance and distribution of 296 native understory species across 82 sites over 55 years in the fragmented forests of southern Wisconsin. We resurveyed stands first surveyed in the early 1950s to evaluate the influence of patch size and surrounding land cover on shifts in native plant richness and heterogeneity and to evaluate changes in the relative importance of local site conditions versus the surrounding landscape context as drivers of community composition and structure. Larger forests and those with more surrounding forest cover lost fewer species, were more likely to recruit new species, and had lower rates of homogenization than smaller forests in more fragmented landscapes. Nearby urbanization further reduced both alpha and beta understory diversity. Similarly, understory composition depended strongly on local site conditions in the original survey but only weakly reflected the surrounding landscape composition. By 2005, however, the relative importance of these factors had reversed such that the surrounding landscape structure is now a much better predictor of understory composition than are local site conditions. Collectively, these results strongly support the idea that larger intact habitat patches and landscapes better sustain native species diversity and demonstrate that humans play an increasingly important role in driving patterns of native species diversity and community composition.  相似文献   
188.
    
Much of the biodiversity‐related climate change impacts research has focused on the direct effects to species and ecosystems. Far less attention has been paid to the potential ecological consequences of human efforts to address the effects of climate change, which may equal or exceed the direct effects of climate change on biodiversity. One of the most significant human responses is likely to be mediated through changes in the agricultural utility of land. As farmers adapt their practices to changing climates, they may increase pressure on some areas that are important to conserve (conservation lands) whereas lessening it on others. We quantified how the agricultural utility of South African conservation lands may be altered by climate change. We assumed that the probability of an area being farmed is linked to the economic benefits of doing so, using land productivity values to represent production benefit and topographic ruggedness as a proxy for costs associated with mechanical workability. We computed current and future values of maize and wheat production in key conservation lands using the DSSAT4.5 model and 36 crop‐climate response scenarios. Most conservation lands had, and were predicted to continue to have, low agricultural utility because of their location in rugged terrain. However, several areas were predicted to maintain or gain high agricultural utility and may therefore be at risk of near‐term or future conversion to cropland. Conversely, some areas were predicted to decrease in agricultural utility and may therefore prove easier to protect from conversion. Our study provides an approximate but readily transferable method for incorporating potential human responses to climate change into conservation planning. Uso de Cambios en la Utilidad Agrícola para Cuantificar Riesgos Futuros para la Conservación Inducidos por el Clima  相似文献   
189.
Abstract:  The world's grasslands and large migratory populations of wildlife have been disproportionately lost or disrupted by human activities, yet are poorly represented in protected areas. The major threats they face are land subdivision and the loss of large-scale dynamic processes such as wildlife migrations and fire. The large-scale dynamical processes and ubiquity of livestock economies and cultures across the grasslands calls for an integrated ecosystem approach to conservation to make up the shortfall in protected-area coverage. Ranchers and pastoralists will be more inclined to adopt an integrated landscape approach to conservation if they also see the threats to wildlife and grassland ecosystems as affecting their livelihoods and way of life. We arranged a series of learning exchanges between African and American pastoralists, ranchers, scientists, and conservationists aimed at building the collaboration and consensus needed to conserve grasslands at a landscape level. There was broad agreement on the threat of land fragmentation to livelihoods, wildlife, and grasslands. The exchanges also identified weaknesses in prevailing public, private, and community modes of ownership in halting fragmentation. New collaborative approaches were explored to attain the benefits of privatization while keeping the landscape open. The African–U.S. exchanges showed that learning exchanges can anticipate over-the-horizon problems and speed up the feedback loops that underlie adaptive management and build social and ecological resilience.  相似文献   
190.
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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