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71.
Abstract:  Collection-based institutions—zoos, aquariums, museums, and botanical gardens—exhibit wildlife and thus have a special connection with nature. Many of these institutions emphasize a mission of conservation, and, undeniably, they do contribute directly to conservation education and conservation science. They present an exceptional opportunity for many urban residents to see the wonders of life, and they can contribute to education and habitat preservation. Because many collection-based institutions now hold a stated mission of conservation, we suggest eight potential questions to evaluate actions toward that mission: (1) Does conservation thought define policy decisions? (2) Is there sufficient organizational funding for conservation activities? (3) Is there a functional conservation department? (4) Does the institution advocate for conservation? (5) Do conservation education programs effectively target children and adults? (6) Does the institution contribute directly to habitat protection locally and internationally? (7) Do exhibits explain and promote conservation efforts? and (8) Do internal policies and activities protect the environment? These questions are offered as a place to begin discussion. We hope they will help employees and administrators of a collection-based institution (and citizens of the surrounding community) think about and support their institution's conservation activities. Public support and praise for institutions that are striving toward solutions for conservation problems and pressure on organizations that are moving more slowly toward a conservation orientation can help shift more resources toward saving nature.  相似文献   
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Abstract: Many of the skills and resources associated with botanic gardens and arboreta, including plant taxonomy, horticulture, and seed bank management, are fundamental to ecological restoration efforts, yet few of the world's botanic gardens are involved in the science or practice of restoration. Thus, we examined the potential role of botanic gardens in these emerging fields. We believe a reorientation of certain existing institutional strengths, such as plant‐based research and knowledge transfer, would enable many more botanic gardens worldwide to provide effective science‐based support to restoration efforts. We recommend botanic gardens widen research to include ecosystems as well as species, increase involvement in practical restoration projects and training practitioners, and serve as information hubs for data archiving and exchange.  相似文献   
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Abstract:  The rainforests of the Amazon basin are being cut by humans at a rate >20,000 km2/year, leading to smaller and more isolated patches of forest, with remaining fragments often in the range of 1–100 ha. We analyzed samples of understory birds collected over 20 years from a standardized mist-netting program in 1– to 100-ha rainforest fragments in a dynamic Amazonian landscape near Manaus, Brazil. Across bird guilds, the condition of second growth immediately surrounding fragments was often as important as fragment size or local forest cover in explaining variation in abundance. Some fragments surrounded by 100 m of open pasture showed reductions in insectivorous bird abundance of over 95%, even in landscapes dominated by continuous forest and old second growth. These extreme reductions may be typical throughout Amazonia in small (≤10 ha), isolated fragments of rainforest. Abundance for some guilds returned to preisolation levels in 10- and 100-ha fragments connected to continuous forest by 20-year-old second growth. Our results show that the consequences of Amazonian forest loss cannot be accurately described without explicit consideration of vegetation dynamics in matrix habitat. Any dichotomous classification of the landscape into "forest" and "nonforest" misses essential information about the matrix.  相似文献   
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Abstract:  As tropical forests are cleared, a greater proportion of migratory songbirds are forced to winter in agricultural and disturbed habitats, which, if poorer in quality than natural forests, could contribute to population declines. We compared demographic indicators of habitat quality for a focal species, the American Redstart ( Setophaga ruticilla ), wintering in Jamaican citrus orchards and shade coffee plantations with those in four natural habitats: mangrove, coastal scrub, coastal palm, and dry limestone forests. Demographic measures of habitat quality included density, age and sex ratio, apparent survival, and changes in body mass. Measures of habitat quality for redstarts in citrus and coffee habitats were generally intermediate between the highest (mangrove) and lowest (dry limestone) measurements from natural habitats. The decline in mean body mass over the winter period was a strong predictor of annual survival rate among habitats, and we suggest that measures of body condition coupled with survival data provide the best measures of habitat quality for nonbreeding songbirds. Density, which is far easier to estimate, was correlated with these more labor-intensive measures, particularly in the late winter when food is likely most limiting. Thus, local density may be useful as an approximation of habitat quality for wintering migrant warblers. Our findings bolster those of previous studies based on bird abundance that suggest arboreal agricultural habitats in the tropics can be useful for the conservation of generalist, insectivorous birds, including many migratory passerines such as redstarts.  相似文献   
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Abstract:  Climate change poses a challenge to the conventional approach to biodiversity conservation, which relies on fixed protected areas, because the changing climate is expected to shift the distribution of suitable areas for many species. Some species will persist only if they can colonize new areas, although in some cases their dispersal abilities may be very limited. To address this problem we devised a quantitative method for identifying multiple corridors of connectivity through shifting habitat suitabilities that seeks to minimize dispersal demands first and then the area of land required. We applied the method to Proteaceae mapped on a 1-minute grid for the western part of the Cape Floristic Region of South Africa, to supplement the existing protected areas, using Worldmap software. Our goal was to represent each species in at least 35 grid cells (approximately 100 km2) at all times between 2000 and 2050 despite climate change. Although it was possible to achieve the goal at reasonable cost, caution will be needed in applying our method to reserves or other conservation investments until there is further information to support or refine the climate-change models and the species' habitat-suitability and dispersal models.  相似文献   
79.
Monitoring and Evaluation in Conservation: a Review of Trends and Approaches   总被引:12,自引:0,他引:12  
Abstract:  There is growing recognition among conservation practitioners and scholars that good project management is integrally linked to well-designed monitoring and evaluation systems. Most conservation organizations have attempted to develop and implement monitoring and evaluation systems, often with mixed results. One problem seems to be that organizations are trying to build their systems from scratch, overlooking lessons learned from the many efforts to develop useful and practical monitoring and evaluation approaches. Thus, we undertook a review of monitoring and evaluation approaches in conservation and other fields including international development, public health, family planning, education, social services, and business. Here, we present our results for the field of conservation. We categorized the considerable variety of monitoring and evaluation approaches into four broad purposes: basic research; accounting and certification; status assessment; and effectiveness measurement. We focus here on status assessment and effectiveness measurement. Specific lessons that emerged follow: different monitoring and evaluation needs require different approaches; conceptual similarities are widespread among prevailing approaches; inconsistent language impedes communication; confusion among monitoring and evaluation components hinders practitioner ability to choose the appropriate component; and monitoring only quantitative biological variables is insufficient. We suggest that the conservation community continue support of collaborative initiatives to improve monitoring and evaluation, establish clear definitions of commonly used terms, clarify monitoring and evaluation system components, apply available approaches appropriately, and include qualitative and social variables in monitoring efforts.  相似文献   
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/ This paper presents an approach for producing aquifer sensitivity maps from three-dimensional geologic maps, called stack-unit maps. Stack-unit maps depict the succession of geologic materials to a given depth, and aquifer sensitivity maps interpret the successions according totheir ability to transmit potential contaminants. Using McHenry County, Illinois, as a case study, stack-unit maps and an aquifer sensitivity assessment were made to help land-use planners, public health officials, consultants, developers, and the public make informed decisions regarding land use. A map of aquifer sensitivity is important for planning because the county is one of the fastest growing counties in the nation, and highly vulnerable sand and gravel aquifers occur within 6 m of ground surface over 75% of its area. The aquifer sensitivity map can provide guidance to regulators seeking optimal protection of groundwater resources where these resources are particularly vulnerable. In addition, the map can be used to help officials direct waste-disposal and industrial facilities and other sensitive land-use practices to areas where the least damage is likely to occur, thereby reducing potential future liabilities. KEY WORDS: Geologic mapping; Groundwater; Aquifers; Aquifer sensitivity; Land-use planning  相似文献   
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