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1.
Protected areas’ chief conservation objectives are to include species within their boundaries and protect them from negative external pressures. Many protected areas are not achieving these goals, perhaps in part due to land development inside and outside protected areas. We conducted spatial analyses to evaluate the ability of Canadian protected areas to mitigate the effects of nearby land development. We investigated correlations of national patterns of land development in and around protected areas and then examined national patterns of roads, urban area, and croplands in protected areas. We calculated the amount of developed land in protected areas and within 25–100 km of protected‐area borders, the density of roads, and extent of urban and cropland area in protected areas. We constructed logistic‐regression models to test whether development in a protected area was associated with landscape and protected‐area characteristics. Land development was far less extensive inside than outside protected areas. However, several protected areas, particularly small southern areas near small urban centers had substantial development inside their boundaries, and nearly half of protected areas had roads. The cumulative extent of development within 50 km of protected areas was the best predictor of the probability of land development in protected areas. Canadian First Nations, industries, government, and nongovernmental organizations are currently planning an unprecedented number of new protected areas. Careful management of areas beyond protected‐area boundaries may prove critical to meeting their long‐term conservation objectives. Desarrollo de Tierras Dentro y Alrededor de Áreas Protegidas en la Frontera Silvestre  相似文献   

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It is widely accepted that the main driver of the observed decline in biological diversity is increasing human pressure on Earth's ecosystems. However, the spatial patterns of change in human pressure and their relation to conservation efforts are less well known. We developed a spatially and temporally explicit map of global change in human pressure over 2 decades between 1990 and 2010 at a resolution of 10 km2. We evaluated 22 spatial data sets representing different components of human pressure and used them to compile a temporal human pressure index (THPI) based on 3 data sets: human population density, land transformation, and electrical power infrastructure. We investigated how the THPI within protected areas was correlated to International Union for Conservation of Nature (IUCN) management categories and the human development index (HDI) and how the THPI was correlated to cumulative pressure on the basis of the original human footprint index. Since the early 1990s, human pressure increased 64% of the terrestrial areas; the largest increases were in Southeast Asia. Protected areas also exhibited overall increases in human pressure, the degree of which varied with location and IUCN management category. Only wilderness areas and natural monuments (management categories Ib and III) exhibited decreases in pressure. Protected areas not assigned any category exhibited the greatest increases. High HDI values correlated with greater reductions in pressure across protected areas, while increasing age of the protected area correlated with increases in pressure. Our analysis is an initial step toward mapping changes in human pressure on the natural world over time. That only 3 data sets could be included in our spatio‐temporal global pressure map highlights the challenge to measuring pressure changes over time. Mapeo del Cambio en la Presión Humana Global en Tierra y Dentro de Áreas Protegidas  相似文献   

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Organochlorine contaminants (HCHs, DDTs and PCBs) in the muscle tissues of 12 bird species collected from Vellar River watershed areas (S. India) were determined. the accumulation pattern of organochlorine residues in birds of different feeding groups for HCHs and PCBs was: scavengers > inland piscivores > coastal piscivores > insectivores. the pattern for DDTs was: coastal piscivores > scavengers > insectivores > inland piscivores. Scavengers accumulated all the three organochlorines to a higher degree than the other groups of birds. Marked variations in the accumulation pattern by different species and individuals of birds to the same and different organochlorine residues were observed. the differences in the accumulation pattern of residues in different species of birds with similar feeding habits could be attributed to different feeding areas and because migrants are exposed to contaminants in different geographical locations. HCH residues were generally found in higher concentrations than DDTs, reflecting increasing use of HCH pesticides since banning of DDT for agriculture. Levels of PCBs were lower than in birds in developed countries. Results are discussed in relation to future pest control and industrialisation in India.  相似文献   

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Abstract:  The physical, economic, and sociocultural displacement of local peoples from protected areas generates intense discussion among scholars and policy makers. To foster greater precision and clarity in these discussions, we used a conceptual framework from the political economy literature to examine different forms of human displacement from protected areas. Using marine protected areas (MPAs) to ground our analysis, we characterized the 5 types of property rights that are reallocated (lost, secured, and gained) through the establishment of protected areas. All forms of MPA "displacement" involve reallocation of property rights, but the specific types and bundles of rights lost, secured, and gained dramatically shape the magnitude, extent, and equity of MPA impacts—positive and negative—on governance, economic well-being, health, education, social capital, and culture. The impacts of reallocating rights to MPA resources vary within and among social groups, inducing changes in society, in patterns of resource use, and in the environment. To create more environmentally sustainable and socially just conservation practice, a critical next step in conservation social science research is to document and explain variation in the social impacts of protected areas.  相似文献   

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Indirect Benefits of Marine Protected Areas for Juvenile Abalone   总被引:1,自引:0,他引:1  
Abstract: Marine protected areas ( MPAs) designed to provide harvest refugia for red sea urchins (  Strongylocentrotus franciscanus ) offer a unique opportunity to study the indirect effects of urchin fishing on subtidal communities. Sea urchins may provide important cryptic microhabitat for juvenile abalone sheltering beneath urchin spines in shallow habitats worldwide. We investigated the abundance of juvenile (3–90 mm) red abalone, (    Haliotis rufescens ) and the rare flat ( <90 mm) abalone (   H. walallensis ) on protected and fished rocky reefs in California. Abalone abundance surveys were conducted inside 24 × 30 m plots on three protected reefs with red sea urchins present and three fished reefs where red sea urchins were removed by commercial or experimental fishing. Significantly more juvenile abalone were found in 1996 and 1997 on protected reefs with urchins present than on fished reefs ( χ   2 = 188, df = 1, p < 0.001 ). Juvenile red abalone abundance was not correlated with local adult red abalone abundance or habitat rugosity. One-third of the juveniles inside the MPAs were found under the urchins' spine canopy, as were a suite of unfished marine organisms. In the laboratory, juvenile abalone survived better (  χ   2 = 7.31, df = 1, p < 0.01) in crab predation experiments in which red sea urchins were available as shelter. Fishing red urchins reduced structural complexity, potentially decreasing microhabitat available for juvenile abalone. This example demonstrates how MPAs designed for one fished species may help other species, illustrating their usefulness for ecosystem-based fishery management and marine conservation.  相似文献   

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Abstract: Quantifying the extent to which existing reserves meet conservation objectives and identifying gaps in coverage are vital to developing systematic protected‐area networks. Despite widespread recognition of the Philippines as a global priority for marine conservation, limited work has been undertaken to evaluate the conservation effectiveness of existing marine protected areas (MPAs). Targets for MPA coverage in the Philippines have been specified in the 1998 Fisheries Code legislation, which calls for 15% of coastal municipal waters (within 15 km of the coastline) to be protected within no‐take MPAs, and the Philippine Marine Sanctuary Strategy (2004), which aims to protect 10% of coral reef area in no‐take MPAs by 2020. We used a newly compiled database of nearly 1000 MPAs to measure progress toward these targets. We evaluated conservation effectiveness of MPAs in two ways. First, we determined the degree to which marine bioregions and conservation priority areas are represented within existing MPAs. Second, we assessed the size and spacing patterns of reserves in terms of best‐practice recommendations. We found that the current extent and distribution of MPAs does not adequately represent biodiversity. At present just 0.5% of municipal waters and 2.7–3.4% of coral reef area in the Philippines are protected in no‐take MPAs. Moreover, 85% of no‐take area is in just two sites; 90% of MPAs are <1 km2. Nevertheless, distances between existing MPAs should ensure larval connectivity between them, providing opportunities to develop regional‐scale MPA networks. Despite the considerable success of community‐based approaches to MPA implementation in the Philippines, this strategy will not be sufficient to meet conservation targets, even under a best‐case scenario for future MPA establishment. We recommend that implementation of community‐based MPAs be supplemented by designation of additional large no‐take areas specifically located to address conservation targets.  相似文献   

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Abstract:  The Iberian Peninsula harbors about 50% of European plant and terrestrial vertebrate species and more than 30% of European endemic species. Despite the global recognition of its importance, the selection of protected areas has been ad hoc and the effectiveness of such choices has rarely been assessed. We compiled the most comprehensive distributional data set of Iberian terrestrial plant and vertebrate species available to date and used it to assess the degree of species representation within existing protected areas. Existing protected areas in Spain and Portugal reasonably represented the plant and animal species we considered (73–98%). Nevertheless, species of some groups (amphibians, reptiles, birds, and gymnosperms) did not accumulate in protected areas at a rate higher than expected by chance ( p > 0.05). We determined that to conserve all vertebrate and plant species in the Iberian Peninsula, at least 36 additional areas are needed. Selection of additional areas for conservation would be facilitated if such areas coincided with sites of community importance (SCI) designated under the European Commission Habitats Directive. Additional areas required for full representation of the selected plant and animal species all coincide with SCI in Spain. Nevertheless, the degree of coincidence varies between 0.3% and 74.6%, and there is a possibility that important areas for conservation occur outside the SCI. Our results support the view that current SCI can be used for prioritization of areas for conservation, but a systematic reevaluation of conservation priorities in Spain and Portugal would be necessary to ensure that effective conservation of one of European's most important biodiversity regions is achieved.  相似文献   

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Protected Areas and Conservation of Biodiversity in the Tropics   总被引:7,自引:0,他引:7  
Abstract: We compared deforestation rates and the extent of fragmentation inside and outside protected areas in the Sarapiquí region of Costa Rica. We determined deforestation rates using remotely sensed images with supervised classification. We georeferenced the processed images and then transformed them to vector format for final mapping and parameter quantification. The deforestation rate in protected areas was low and declined sharply from 0.56% annually between 1976 and 1986 to 0.16% from 1991 to 1995. Outside the protected areas, the rate decreased from 3.6% in 1976–1986 to 2.8% in 1986–1991, but it increased again to 3.2% in 1991–1995. Fragmentation outside the protected areas increased considerably: the number of patches increased from 537 in 1976 to 1231 in 1996, while during the same period the average size of patches decreased from 0.95 to 0.25 km2. Forest landscapes in the Sarapiquí region are likely to lose considerable biodiversity because of the past forest loss and fragmentation even without further increases in deforestation and fragmentation.  相似文献   

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Protected Areas and Prospects for Endangered Species Conservation in Canada   总被引:3,自引:0,他引:3  
Abstract:  Reserve networks figure prominently in conservation strategies that aim to reduce extinction rates. We tested the effectiveness of the current reserve network at protecting species at risk in Canada, where relatively extensive wilderness areas remain. We compared numbers of terrestrial species at risk included in existing reserves to randomly generated networks with the same total area and number of reserves. Existing reserve networks rarely performed better than randomly selected areas and several included fewer endangered species than expected by chance, particularly in the most biologically imperiled regions. The extent of protected area and density of species at risk were unrelated at either broad (countrywide) or finer spatial scales (50 × 50 km grids), although there was a tendency for the most threatened regions of the country to have few or no protected areas (1.5% of areas with >30 endangered species were in reserves). Although reserves will play a useful role in conserving endangered species that occur within them, reducing extinction rates in a region with much of the world's remaining wilderness will require integrating conservation strategies with agricultural and urban land-use plans outside formally protected areas.  相似文献   

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Abstract:  It is internationally recognized that conservation policies should respect indigenous cultures and consider the livelihoods of people affected by conservation restrictions. Countering this are concerns that human occupation and use of natural reserves is incompatible with conservation aims. But in China today the continued use and management of natural areas by local communities is likely to deliver better conservation outcomes than the current drive to establish public protected areas. The effectiveness of many protected areas in China is compromised by institutional conflicts, lack of ongoing financial and technical support, confusion between the objectives of generating revenue and conservation, dubious scientific definitions, lack of community trust in policies, and obscure user rights and land tenures. Southwestern China—one of the most biologically and ethnologically diverse areas on Earth—is a good illustration of a place where culture and biological diversity are closely linked. The indigenous people in this area have shown that local livelihood practices can be advantageous for the long-term maintenance of conservation goals. Rather than creating new protected areas, we argue that China is better advised to support ongoing sustainable use of natural areas by the people who have lived and nurtured these environments for generations .  相似文献   

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Abstract: Marine protected areas (MPAs) are a popular conservation strategy, but their impacts on human welfare are poorly understood. To inform future research and policy decisions, we reviewed the scientific literature to assess MPA impacts on five indicators of human welfare: food security, resource rights, employment, community organization, and income. Following MPA establishment, food security generally remained stable or increased in older and smaller MPAs. The ability of most fishing groups to govern MPA resources changed. Increased resource rights were positively correlated with MPA zoning and compliance with MPA regulations. Small sample sizes precluded statistical tests of the impacts of MPAs on employment, community organization, and income. Our results demonstrate that MPAs shape the social well‐being and political power of fishing communities; impacts (positive and negative) vary within and among social groups; and social impacts are correlated with some—but not all—commonly hypothesized explanatory factors. Accordingly, MPAs may represent a viable strategy for enhancing food security and empowering local communities, but current practices negatively affect at least a minority of fishers. To inform policy making, further research must better document and explain variation in the positive and negative social impacts of MPAs.  相似文献   

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The global extent of macroalgal forests is declining, greatly affecting marine biodiversity at broad scales through the effects macroalgae have on ecosystem processes, habitat provision, and food web support. Networks of marine protected areas comprise one potential tool that may safeguard gene flow among macroalgal populations in the face of increasing population fragmentation caused by pollution, habitat modification, climate change, algal harvesting, trophic cascades, and other anthropogenic stressors. Optimal design of protected area networks requires knowledge of effective dispersal distances for a range of macroalgae. We conducted a global meta‐analysis based on data in the published literature to determine the generality of relation between genetic differentiation and geographic distance among macroalgal populations. We also examined whether spatial genetic variation differed significantly with respect to higher taxon, life history, and habitat characteristics. We found clear evidence of population isolation by distance across a multitude of macroalgal species. Genetic and geographic distance were positively correlated across 49 studies; a modal distance of 50–100 km maintained FST < 0.2. This relation was consistent for all algal divisions, life cycles, habitats, and molecular marker classes investigated. Incorporating knowledge of the spatial scales of gene flow into the design of marine protected area networks will help moderate anthropogenic increases in population isolation and inbreeding and contribute to the resilience of macroalgal forests. Implicaciones del Aislamiento por Distancia de Macroalgas para Redes de Áreas Marinas Protegidas  相似文献   

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Indigenous Peoples and Protected Areas at the World Parks Congress   总被引:2,自引:1,他引:1  
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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   

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Most people follow and are influenced by some kind of spiritual faith. We examined two ways in which religious faiths can in turn influence biodiversity conservation in protected areas. First, biodiversity conservation is influenced through the direct and often effective protection afforded to wild species in sacred natural sites and in seminatural habitats around religious buildings. Sacred natural sites are almost certainly the world's oldest form of habitat protection. Although some sacred natural sites exist inside official protected areas, many thousands more form a largely unrecognized "shadow" conservation network in many countries throughout the world, which can be more stringently protected than state-run reserves. Second, faiths have a profound impact on attitudes to protection of the natural world through their philosophy, teachings, investment choices, approaches to land they control, and religious-based management systems. We considered the interactions between faiths and protected areas with respect to all 11 mainstream faiths and to a number of local belief systems. The close links between faiths and habitat protection offer major conservation opportunities, but also pose challenges. Bringing a sacred natural site into a national protected-area system can increase protection for the site, but may compromise some of its spiritual values or even its conservation values. Most protected-area managers are not trained to manage natural sites for religious purposes, but many sacred natural sites are under threat from cultural changes and habitat degradation. Decisions about whether or not to make a sacred natural site an "official" protected area therefore need to be made on a case-by-case basis. Such sites can play an important role in conservation inside and outside official protected areas. More information about the conservation value of sacred lands is needed as is more informed experience in integrating these into wider conservation strategies. In addition, many protected-area staff need training in how to manage sensitive issues relating to faiths where important faith sites occur in protected areas.  相似文献   

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