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491.
The landscape surrounding protected areas influences their ability to maintain ecosystem functions and achieve conservation goals. As anthropogenic intensification continues, it is important to monitor land-use and land-cover change in and around protected areas. We measure land-cover change surrounding protected areas in the Maputaland-Pondoland-Albany Biodiversity hotspot from the 1980s to present. Using Landsat imagery, we classified land cover within and around each protected area. Agricultural land uses were increasing and often directly border protected area boundaries. Human settlements increased around every protected area, potentially increasing human activity along the edges of protected areas and threatening their ecological integrity. Urban expansion around protected areas varied but increased as much as 10%. Woody vegetation cover varied both within and around protected areas with possible evidence of deforestation and shrub encroachment throughout the hotspot. We recommend monitoring land cover across southeastern Africa to better understand regional trends in land-use impacts to protected areas.  相似文献   
492.
Conflicts between protected-area managers and local people are common, but the drivers of conflict are rarely analyzed. This limits opportunities to identify strategies that reduce conflict and the magnitude of resulting threats to conservation. Integrated conservation and development (ICD) was adopted at Bwindi Impenetrable Forest, Uganda, to reduce conflict during gazettement of the national park, but the success of this approach remains contested. We retrieved documents of conflict written by park staff and local people from 1986 through 2000 (before, during, and after gazettement). We extracted data on 48 incidences of violent conflict and categorized them by gazettement period, area, instigator, and type to undertake a historical analysis of the triggers of violent conflict at Bwindi. Before and during gazettement, local villagers instigated most of the conflict incidents when law-enforcement efforts sought to halt commercial activities within Bwindi. No conflict arose from the arrest of villagers collecting subsistence resources during these periods. After gazettement, prohibitions on commercial activities continued to drive conflict even though villagers collecting subsistence resources were arrested more frequently than before gazettement, and local attitudes toward the park had improved following receipt of ICD benefits. Law-enforcement efforts targeted commercial activities to reduce this threat to Bwindi's mountain gorillas (Gorilla beringei beringei), although the activities remained important income sources for people in villages near Bwindi. Losing commercial income following gazettement therefore appeared to be their primary motivation for instigating conflict with park rangers. Prohibitions on subsistence resource use triggered conflict less often. Our use of typologies for a multivariate conflict analysis demonstrates that by identifying differences between effects of conservation as drivers of conflict, conflict analysis can enable a more strategic deployment of conflict-resolution measures that could further conservation efforts. At Bwindi targeting ICD toward individuals who lost benefits from commercial activities may strengthen the role of ICD in conflict resolution and conservation.  相似文献   
493.
Abstract:  Moving from single-species- to ecosystem-based management requires an understanding of how community-level attributes such as diversity change with area. We used survey data from bottom trawls to examine spatial patterns of species richness in U.S. Pacific coastal fishes. Specifically, we generated and compared species–area relationships (SARs) for species classified into several groups on the basis of maximum body size, trophic level, diet, maximum depth, geographic affinity, and taxonomic order. Because SARs among groups were not parallel and z values varied significantly for several groups, groups of species were under- or overrepresented (depending on the size of the area) relative to their proportions in the entire community (i.e., entire U.S. Pacific coast). In this way, differences in SARs help demonstrate trade-offs between species representation and coastal area and suggest strategies (such as targeting the protection of habitats and locations where a particular species or groups of species are maximized) that may minimize the size of marine protected areas (MPAs) but protect diversity at the level of the community and functional group.  相似文献   
494.
Conservation Value of Multiple-Use Areas in East Africa   总被引:3,自引:0,他引:3  
Abstract:  Despite wide agreement that strictly protected areas (World Conservation Union categories I–III) are the best strategy for conserving biodiversity, they are limited in extent and exclude many species of key conservation importance. In contrast, multiple-use management areas (categories IV–VI), comprising >60% of the world's protected-area network, are often considered of little value to biodiversity conservation, particularly in Africa, where they typically contain few charismatic large mammals. We sampled small mammals, amphibians, birds, butterflies, and trees at 41 sites along a four-step gradient of increasing human activity and decreasing conservation protection, from a well-protected Tanzanian national park to nonintensive agricultural land. Although preliminary, our results indicate that species richness of these five taxa did not decline along this gradient, but different management areas, occupying areas of largely similar habitat, hosted distinct communities of each taxon. Differences in species composition in the absence of manifest differences in species richness highlight the importance of developing landscape-scale conservation strategies and the danger of using either a limited suite of indicator taxa or umbrella species as surrogates for biodiversity. Although strictly protected areas perform a unique and vital conservation service in East Africa by protecting large mammals, areas that allow varied resource extraction activities still possess vital and complementary conservation value.  相似文献   
495.
Africa contains much of Earth's biological and cultural–linguistic diversity, but conserving this diversity is enormously challenging amid widespread poverty, expanding development, social unrest, and rapidly growing human population. We examined UNESCO (United Nations Educational, Scientific and Cultural Organization) Natural World Heritage Sites (WHSs) on continental Africa and nearby islands—48 protected areas containing globally important natural or combined natural and cultural resources—to gauge the potential for enlisting Indigenous peoples in their conservation. We used geographic information system technology to identify instances where Natural WHSs co-occur with Indigenous languages, a key indicator of cultural diversity. And, we compared the geographic ranges for 4 taxa and selected freshwater species with occurrence of all Indigenous languages within Natural WHSs and subsections of WHSs covered by the geographic extent of Indigenous languages to measure the correlation between linguistic and biological diversity. Results indicated that 147 languages shared at least part of their geographic extent with Natural WHSs. Instances of co-occurrence where a WHS, a language, or both were endangered marked localities particularly deserving conservation attention. We examined co-occurrence of all languages and all species, all languages and endangered species, and endangered languages and endangered species and found a correlation between linguistic and biological diversity that may indicate fundamental links between these very different measures of diversity. Considering only endangered species or endangered languages and species reduced that correlation, although considerable co-occurrence persisted. Shared governance of government-designated reserves is applicable for natural WHSs because it capitalizes on the apparent connection between culture and nature. Natural WHSs in Africa containing speakers of Indigenous languages present opportunities to conserve both nature and culture in highly visible settings where maintaining natural systems may rely on functioning Indigenous cultural systems and vice versa.  相似文献   
496.
Traditionally, the criteria used to measure conservation success or failure are based on biological factors. Biological factors include changes in the amount of targeted conserved species, biodiversity, and total area conserved. However, conservation efforts are not simply a matter of biological concern; environmental, political, social, and conflict pressures on different scales (ranging from local to global) also have strong influences on the outcome of conservation. These other factors can either pose threats to or enhance conservation, but are not addressed by current criteria. Using a proposed holistic rubric that includes interdisciplinary fields, this paper examines a set of conservation factors on different scales – ranging from local to global – to determine their importance in conservation. The paper analyses positive factor influences with more successful conservation and negative factor influences with less successful, or failed, conservation attempts. Neutral and non‐applicable factor influences are also identified, defined, and ranked as a standardization mechanism. The determination of success changed when the holistic rubric was applied to conservation projects in Costa Rica, Mekong Valley, and Cameroon. In the Costa Rica case study, conservation success for Guanacaste and Talamanca national parks is rated ‘moderately low’. In the case of Mekong Valley, conservation success is rated ‘low’ for Lower Mekong, ‘moderately low’ for Greater Annamites, and ‘low’ for Phong Nha‐Ke Bang national parks. Cameroon's Congo Basin and Sangha Tri‐National conservation efforts are both rated ‘low’, while Dja Faunal is rated ‘very low’. We conclude that if conservation efforts are to attain a high level of success, the strategy for global conservation must move away from the traditional biological approach, which focuses mainly on biological concerns, and embrace a holistic approach, which in addition to biological concerns, addresses environmental, political, social, and conflict pressures, which have strong influences on the outcomes of conservation.  相似文献   
497.
In the present study, forest biomass (fuelwood, leaf fodder, leaf-litter and non-timber forest products) consumption patterns have been evaluated in the villages of Govind Wildlife Sanctuary, Uttarakhand, Western Himalaya, India. The average fuelwood consumption in the selected villages was estimated at 3.14 kg/capita/day and its energy equivalent was found 52.74 MJ/capita/day. The average leaf fodder and leaf-litter consumption was estimated at 2.70 and 2.40 kg/unit/day, respectively, and the same pattern was estimated for energy equivalent. People's perception on impacts of conservation measures and resources utilization rights were also analysed. Our results emphasized the need for regular assessment of forest resources, particularly in protected areas, where access to natural resources have been denied due to legal restrictions. The study could be a pilot to strengthen the conservation measures across the protected area network by understanding the dynamics of anthropocentric activities and their subsequent impacts on forest resources.  相似文献   
498.

Boston Chinatown is a community that grapples with a constant pressure from the downtown area to build new and larger buildings. The effort to preserve the residential aspect of Chinatown has used data analysis in recent years by forming partnerships with academics. This has allowed for more sophisticated studies of traffic injuries, scientific surveys of residents about environmental health, the measurement of noise levels and the construction of physical and electronic mapping of data. While not the only factor contributing to the community's efforts to question the role of development, these data have added useful tools that reduce, but do not eliminate, the disparity between what the community brings to discussions about the environmental impact of development and what the developers have at their disposal.  相似文献   
499.
Even after 30 years of strict de jure protection, today's de facto extraction of products from Nepal's Royal Chitwan National Park (RCNP) and their great economic importance to local households suggests that this reality should be explicitly internalised in managing this world heritage park. Several studies have quantified local people's use of protected areas and estimated the value of such areas to them. However, few studies incorporate economic analyses to investigate the effect of management interventions on local communities' resource use and collection behaviour. In Nepal, buffer zones and especially buffer zone community forestry are seen as means to define and demarcate places, where local people may legally extract goods that are either identical to or relevant substitutes for products that are collected in protected areas. The intention is to resolve park-people conflicts over resource use. This article presents the findings of an in-depth study of the importance of natural resources to the livelihoods of 18 households. One village was located inside RCNP with no realistic alternatives to Park resources, while the other is located in the buffer zone with equal distance to the Park, a national forest and their community forest. For each household, the collection of products, allocation of time, and purchase and sale of goods were recorded daily through 12 consecutive months and economic values were calculated on the basis of local market prices and recorded quantities. The study shows that products from RCNP are of great importance to the livelihoods of local people. Furthermore, we find that products collected in the national forest substitute products from the Park, while the substitution effect of the community forest is small. Accordingly, the study illustrates that, irrespective of buffer zone community forestry, there is still a gap between local people's need for supplementing natural resources and their rights to satisfy them on a legal basis, which is likely to be unsustainable in the longer term. This calls for a thorough evaluation of actual park-people relations and how these may be improved through local participation that goes beyond the current form of buffer zone community forestry and the admitted 7-14 annual days of open access grass cutting within the park.  相似文献   
500.
西洞庭湖湿地鸟类群落组成、多样性及保护对策   总被引:1,自引:0,他引:1  
采用固定样带法和样点法对湖南西洞庭湖自然保护区的鸟类群落进行了研究,共纪录到217种,隶属16目46科117属,其中冬候鸟113种、旅鸟1种、留鸟60种、夏候鸟43种,分别占5207%、046%、2765%、1982%;古北界种类102种 (占4700 %),东洋界种类 67种 (占3088%),广布型种类 48种 (占2212 %);国家Ⅰ级保护种类4种,国家Ⅱ级保护种类29种。鸟类群落多样性指数和均匀性指数分别为4886 5和0594 9。并分析其湿地鸟类的重要性和稀缺性,提出了相应的保护措施。  相似文献   
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