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1.
Expansion of the global terrestrial protected area system   总被引：2，自引：0，他引：2  
Under the Convention on Biological Diversity, the world’s governments set a goal of protecting 10% of all ecological regions by 2010. We evaluated progress toward that goal for the world’s major terrestrial biomes, realms, and ecoregions. Total land area under any legal protection has increased from previous estimates to 12.9%, a notable achievement, although only 5.8% has strict protection for biodiversity. For biomes, protection ranges from 4% to 25%, with six of 14 biomes still below the 10% level. Geographic patterns of protection have a distinct bias, with higher rates of protection in New World realms than Old World realms. Of the world’s terrestrial ecoregions, half do not meet the 2010 Target and 76% have less than 10% of their area strictly protected. Approximately 13% of ecoregions have no strict protected areas. Recent years have seen an expansion of the protected area network, with an average of 0.13% of the global land area added per year. Most of the expansion since 2003 though has been in Brazil, particularly the Amazon. Without major investments in conservation, spread across the world’s ecosystems, the world will likely miss the 2010 target.  相似文献   

2.
Changes in biodiversity may disrupt the ecological functions performed by species assemblages. Hence, we urgently need to examine the implications of biodiversity loss not only in terms of species conservation but also in terms of sustainability of ecosystem services. The ability of protected areas to maintain local species richness has been clearly demonstrated. However, preserving goods and services provided by ecosystems requires not only the conservation of species richness but also the conservation of the most ‘original’ species, i.e. the ones with the highest average rarity of their attributes which are likely to perform some unique functions in ecosystems. We proposed a new conservation of biological originality (CBO) index as well as associated randomization tests to quantify the ability of protected areas to maintain viable populations for the most original species. As an application, we used long-term fisheries data collected in the Bonifacio Strait Natural Reserve (BSNR) to determine the species which benefited from the protection reinforcement in 1999. We also estimated a set of 14 ecomorphological functional traits on the 37 fish species caught in the BSNR and we obtained a functional originality value for each species. As a result, we found that functional originality was significantly protected in the fish assemblage of the BSNR: species with the most original functional trait combinations became more abundant after 1999. Our finding suggests that protecting most original species is an insurance against functional diversity erosion in the BSNR. More generally, our new index can be used to test whether protected areas may protect preferentially the most original species and whether restorative management promotes the reestablishment of the most original species with particular habitat requirements.  相似文献   

3.
The Central African Republic (CAR) has made an impressive commitment to biodiversity conservation, with a total of 15 protected areas covering about 10.9% of the country. This study critically examines the status of these protected areas in light of their potential for long-term protection of biodiversity. First of all, the protected area system does not protect a representative sample of the ecoregions of the CAR. Even more important is the fact that only 32% of the protected areas are adequately managed. Law-enforcement is inadequate, and poaching poses the largest threat to biodiversity conservation. Given the dim economic prospects, the CAR will need continued financial as well as technical assistance to deal with protected area management. Experiences have shown that such intervention can make a difference. However more attention needs to be given to capacity building, long-term funding mechanisms, regional collaboration and political commitment to make such interventions sustainable in the long-term.  相似文献   

4.
This study presents a global analysis of forest cover and forest protection. An updated Global Forest Map (using MODIS2005) provided a current assessment of forest cover within 20 natural forest types. This map was overlaid onto WWF realms and ecoregions to gain additional biogeographic information on forest distribution. Using the 2008 World Database on Protected Areas, percentage forest cover protection was calculated globally, within forest types, realms and ecoregions, and within selected areas of global conservation importance. At the 10% tree cover threshold, global forest cover was 39 million km2. Of this, 7.7% fell within protected areas under IUCN management categories I–IV. With the inclusion of IUCN categories V and VI, the level of global forest protection increased to 13.5%. Percentage forest protection (IUCN I–IV) varied greatly between realms from 5.5% (Palearctic) to 13.4% (Australasia), and for forest types from 3.2% (temperate freshwater swamp forest) to 28% (temperate broadleaf evergreen forest). Median protection of forest cover in 670 ecoregions (forest above a specified threshold) was 5.9% (IUCN I–IV); at IUCN I–VI, 46% of the ecoregions had less than 10% forest protection. Considering their biodiversity importance, forest protection within global priority areas was insufficient, e.g., median protection of 8.4% in biodiversity hotspots (IUCN I–IV). Results have policy relevance in terms of the target of the Convention on Biological Diversity (CBD), reconfirmed in 2008, to effectively conserve “at least 10% of each of the world’s forest types”. Regular updates of these analyses would allow progress towards achieving that target to be monitored.  相似文献   

5.
Through the Convention on Biological Diversity (CBD), the world’s governments recently adopted a target to protect “at least 17% of terrestrial and inland water areas” by 2020. One of the CBD’s thematic programmes of work focuses on mountains, given their importance for biodiversity and other ecosystem services, and their vulnerability to global change. We evaluated current levels of protection for mountains at multiple scales. Encouragingly, the CBD’s 17% target has already been almost met at a global scale: 16.9% of the world’s mountain areas outside Antarctica fall within protected areas. However, protection of mountain areas at finer scales remains uneven and is largely insufficient, with 63% (125) of countries, 57% (4) of realms, 67% (8) of biomes, 61% (437) of ecoregions and 53% (100) of Global 200 priority ecoregions falling short of the target. The target also calls for protected areas to be focussed “especially [at] areas of particular importance for biodiversity”. Important Bird Areas and Alliance for Zero Extinction sites represent existing global networks of such sites. It is therefore of major concern that 39% and 45% respectively of these sites in mountain areas remain entirely unprotected. Achievement of the 2020 CBD target in mountain regions will require more focused expansion of the protected area network in addition to enhanced management of individual sites and the wider countryside in order to ensure long term conservation of montane biodiversity and the other ecosystem services it provides.  相似文献   

6.
Reserves are often designed to protect rare habitats, or “typical” exemplars of ecoregions and geomorphic provinces. This approach focuses on current patterns of organismal and ecosystem-level biodiversity, but typically ignores the evolutionary processes that control the gain and loss of biodiversity at these and other levels (e.g., genetic, ecological). In order to include evolutionary processes in conservation planning efforts, their spatial components must first be identified and mapped. We describe a GIS-based approach for explicitly mapping patterns of genetic divergence and diversity for multiple species (a “multi-species genetic landscape”). Using this approach, we analyzed mitochondrial DNA datasets from 21 vertebrate and invertebrate species in southern California to identify areas with common phylogeographic breaks and high intrapopulation diversity. The result is an evolutionary framework for southern California within which patterns of genetic diversity can be analyzed in the context of historical processes, future evolutionary potential and current reserve design. Our multi-species genetic landscapes pinpoint six hotspots where interpopulation genetic divergence is consistently high, five evolutionary hotspots within which genetic connectivity is high, and three hotspots where intrapopulation genetic diversity is high. These 14 hotspots can be grouped into eight geographic areas, of which five largely are unprotected at this time. The multi-species genetic landscape approach may provide an avenue to readily incorporate measures of evolutionary process into GIS-based systematic conservation assessment and land-use planning.  相似文献   

7.
There has been very little consideration of freshwater ecosystems in identifying and designing protected areas. Recent studies suggest that protected areas hold enormous potential to conserve freshwater biodiversity if augmented with appropriate planning and management strategies. Recognizing this need, South Africa’s relevant government authority commissioned a spatial assessment to inform their national protected area expansion strategy. This study presents the freshwater component of the spatial assessment, aimed at identifying focus areas for expanding the national protected area system for the benefit of river biodiversity. Conservation objectives to guide the assessment aimed to improve representation of river biodiversity pattern and processes in both new and existing protected areas. Data to address these objectives were collated in a Geographic Information System (GIS) and a conservation planning algorithm was used as a means of integrating the multiple objectives in a spatially efficient manner. Representation of biodiversity pattern was based on achieving conservation targets for 222 river types and 47 freshwater fish endemic to South Africa. Options were also identified for representing coarse-scale biodiversity processes associated with free-flowing rivers and catchment-estuarine linkages. River reaches that, with only minor expansion of existing protected area boundaries, could be fully incorporated into the national protected area system were also identified. Based on this study, generic recommendations are made on how to locate, design and manage protected areas for river biodiversity: use appropriate planning units, incorporate both biodiversity pattern and process, improve planning and management of individual protected areas, incorporate a mixture of protection strategies, and embed planning into an ongoing research and implementation process.  相似文献   

8.
Protected areas for conservation are intended to contain the environmental conditions that enable species and ecosystems to persist. The locations of such areas are fixed, but the environment within them may change, especially with climate change. To illustrate how multiple climate factors may change in relation to protection status, we used Principal Components Analysis to construct a climate space for California based on eight climate variables assessed at an 800-m resolution. We used projections of future climate derived from a downscaled regional climate model in conjunction with the IPCC SRES A2 scenario to assess how the climate space might shift under future conditions and to identify the combinations of conditions that may no longer occur in the state (disappearing climates) or that will be new to the state (novel climates). Disappearing climates, which were generally toward cooler and/or wetter extremes of the climate space, represented only 0.5% of California’s land area but occurred disproportionately more often in conservation areas that were fully protected. Novel climates (5.8% of California) also occurred disproportionately in fully protected areas; in most cases these climates were characterized by hotter and drier combinations with more seasonal precipitation. The disproportionate occurrence of both novel and disappearing future climates in currently protected areas may create challenges to conservation of the status quo, but such areas may also be “hotspots of opportunity” for responding to the extremes of climate change.  相似文献   

9.
Biological reserves are established to protect natural resources and represent the diversity of environments found within a region. Unfortunately, many systems of protected areas do not proportionally capture the range of environmental conditions occupied by species and communities. Combinations of habitat loss and climate change may exacerbate these representational biases, and result in future distributions of environmental conditions that bare little resemblance to historic patterns. New protected areas need to be established to correct existing biases, and create conservation networks that remain representative despite climate change, habitat loss, and changes in species distributions. We demonstrate a new method to identify and prioritize habitat based on its value for improving bioclimatic representation. We assessed representation provided by existing protected areas for 301 Proteaceae species under historic and projected 2050 climate across the Cape Floristic Region in South Africa. The existing reserve system has relatively modest biases with respect to current species distributions and climate. However, if the system is not supplemented, protected areas in 2050 will capture an increasingly skewed sample of climatic conditions occupied by Proteaceae. These biases can be repaired through the systematic establishment of new protected areas, and many of the most valuable areas coincide with high priority ecosystem components and irreplaceable elements identified in the Cape Action for People and the Environmental conservation plan. Protecting these areas achieves nearly the best possible improvement in climatic representation while also meeting biodiversity representation goals.  相似文献   

10.
Identifying areas with relevant features of biodiversity is useful to rank priorities for strengthening the design of well-sited natural protected areas and to optimize resource investment in conservation. This study provides decision makers critical tools for highlighting pieces of land worthy of conservation in Spain. We studied four taxa—amphibians, reptiles, nesting birds and mammals—in a 50 × 50 km grid (n=259 cells). We used five criteria for identifying areas of high-value diversity: species richness, rarity, vulnerability, a combined index of biodiversity, and a Standardized Biodiversity Index that measured all four taxa together. As far as we know, the combined index of biodiversity and the Standardized Biodiversity Index are original. Areas of high-value diversity were defined as those cells within the 15% top segment of ranked values for the different criteria. Congruence of areas of high-value diversity for taxa pairs was moderate to low, and averaged 38.5% for areas of high-value diversity based on the combined index of biodiversity. The performance based on the average proportion of threatened species excluded from areas of high-value diversity followed the rank combined index of biodiversity=rarity (0.3%) > vulnerability (9.9%) > species richness (13.8%). The areas of high-value diversity identified according to the Standardized Biodiversity Index included all amphibian and mammal species, all but one reptile species (categorized as rare) and all but six bird species (three of which were categorized as threatened). About 70% of the areas of high-value diversity identified based on the Standardized Biodiversity Index included natural protected areas. However, they average only 274.6 km2, thus occupying a small fraction of the areas of high-value diversity, and there is no guarantee that the species found in an area of high-value diversity site will be present in its protected fraction. Consequently, we urge managers of natural protected areas to conduct diversity surveys. We also urge that additional natural protected areas be established to include the gap of 30% of areas of high-value diversity not currently protected. We took an step for biodiversity conservation planning in the studied region, and discuss the usefulness of maps of areas of high-value diversity for conservation, ecological restoration, and environmental impact assessment and mitigation.  相似文献   

11.
The process of designing protected areas to represent all ecosystems in an area adequately is becoming increasingly sophisticated. To date freshwater aquatic ecosystems have seldom been considered in this process. How much of a difference does it make when they are considered as well?This study examined the conservation of riverine biodiversity within 17 assessment units contained by the catchment areas of five perennial rivers flowing through Kruger National Park and two seasonal rivers that are largely contained within this park. Physical river types, fish species and invertebrate families or genera were used as surrogates of riverine biodiversity. Conservation planning software was used to select an optimal set of planning units to represent and maintain riverine biodiversity.The current spatial configuration of Kruger National Park, largely an accident of history, is particularly poor when assessed against the objective of conserving riverine biodiversity. Several alternative layouts are examined. These options are theoretical since there is little current opportunity to reassign land uses in the region. This study shows that substantially improved layouts for both riverine and terrestrial biodiversity are possible, under the constraint of the same total area under protection. The study also shows that even these optimal layouts are only partially successful in efforts to conserve fully representative samples of riverine biodiversity. Because of the longitudinal connectivity of rivers, conservation strategies that extend beyond protected areas are essential. Explicit conservation visions, targets and strategies need to be included in integrated water resource management plans.Based on the results of this study, nine recommendations are provided for increasing the effectiveness of current and future protected areas in conserving riverine biodiversity. These are to use systematic conservation planning to make biodiversity benefits explicit; mend the disconnect between terrestrial and freshwater conservation; use multiple surrogates wherever possible; be strategic about the collection and management of primary data; strive for maximum hydrologic connectivity; resist development pressure; foster good relationships across park fences; where relevant, pursue multi-national cooperation at the basin scale; and engage the value debate and resolve awareness and capacity constraints.  相似文献   

12.
Due to human population growth and migration, there will be nearly 2 billion new urban residents by 2030, yet the consequences of both current and future urbanization for biodiversity conservation are poorly known. Here we show that urban growth will have impacts on ecoregions, rare species, and protected areas that are localized but cumulatively significant. Currently, 29 of the world’s 825 ecoregions have over one-third of their area urbanized, and these 29 ecoregions are the only home of 213 endemic terrestrial vertebrate species. Our analyses suggest that 8% of terrestrial vertebrate species on the IUCN Red List are imperiled largely because of urban development. By 2030, 15 additional ecoregions are expected to lose more than 5% of their remaining undeveloped area, and they contain 118 vertebrate species found nowhere else. Of the 779 rare species with only one known population globally, 24 are expected to be impacted by urban growth. In addition, the distance between protected areas and cities is predicted to shrink dramatically in some regions: for example, the median distance from a protected area to a city in Eastern Asia is predicted to fall from 43 km to 23 km by 2030. Most protected areas likely to be impacted by new urban growth (88%) are in countries of low to moderate income, potentially limiting institutional capacity to adapt to new anthropogenic stresses on protected areas. In short, trends in global ecoregions, rare species, and protected areas suggest localized but significant biodiversity degradation associated with current and upcoming urbanization.  相似文献   

13.
Biodiversity in Africa, Madagascar and smaller surrounding islands is both globally extraordinary and increasingly threatened. However, to date no analyses have effectively integrated species values (e.g., richness, endemism) ‘non-species’ values (e.g., migrations, intact assemblages), and threats into a single assessment of conservation priorities. We present such an analysis for the 119 ecoregions of Africa, Madagascar and smaller islands. Biodiversity is not evenly distributed across Africa and patterns vary somewhat among taxonomic groups. Analyses of most vertebrates (i.e., birds, mammals, amphibians) tend to identify one set of priority ecoregions, while plants, reptiles, and invertebrates highlight additional areas. ‘Non-species’ biological values are not correlated with species measures and thus indicate another set of ecoregions. Combining species and non-species values is therefore crucial for assembling a comprehensive portfolio of conservation priorities across Africa. Threats to biodiversity are also unevenly distributed across Africa. We calculate a synthetic threat index using remaining habitat, habitat block size, degree of habitat fragmentation, coverage within protected areas, human population density, and the extinction risk of species. This threat index is positively correlated with all three measures of biological value (i.e., richness, endemism, non-species values), indicating that threats tend to be focused on the region’s most important areas for biodiversity. Integrating biological values with threats allows identification of two distinct sets of ecoregion priority. First, highly imperilled ecoregions with many narrow endemic species that require focused actions to prevent the loss of further habitat leading to the extinction of narrowly distributed endemics. Second, less threatened ecoregions that require maintenance of large and well-connected habitats that will support large-scale habitat processes and associated area-demanding species. By bringing these data together we can be much more confident that our set of conservation recommendations serves the needs of biodiversity across Africa, and that the contribution of different agencies to achieving African conservation can be firmly measured against these priorities.  相似文献   

14.
Mexico currently has 144 nature reserves covering approximately 9.1% of its land area. These reserves were established for a variety of reasons—often unrelated to the protection of biodiversity. In 2000 in response to a growing concern about the lack of organized conservation reserve planning to protect the important threatened biological and physical features of Mexico, the Mexican Commission for Knowledge and Use of Biodiversity (CONABIO) proposed the establishment of 151 new reserves for Mexico covering 51,429,500 ha. We compiled a GIS analysis using digital thematic maps of physical and biological features to examine how the existing and proposed reserves serve to protect the biodiversity and physical features of the country. Using a conservation target of placing a minimum of 12% of the land area of each important biophysical feature in nature reserves, we found that the 144 existing nature reserves covering 18 million ha (9% of the country) only meet that target for elevation ranges >3000 m and areas with poor soils. These mountainous areas represent less than 1% of the country. The gaps in the existing nature reserves network occur mainly at lower and intermediate elevations (<3000 m) areas with xeric, tropical, and temperate ecosystems, and high productivity soils. The areas proposed by CONABIO increase the proportion of protected lands in the country to over 27% and most of the conservation targets for geophysical features, and land cover, categories are met. Whether this area would be sufficient to maintain viable populations and ecological integrity of species and ecosystems is unknown. Even with the new reserves, low elevation coastal lands would be below the conservation target in the nature reserves. To include a representative sample of these lands would be difficult as these are the same areas where the majority of people live.  相似文献   

15.
Rio de Janeiro state in Brazil has one of the most diverse and most endangered avifaunas in the continental Americas. Many of these endangered birds are endemic to the Atlantic Forest biodiversity hotspot, and some even endemic to Rio de Janeiro itself. As with all other forested hotspots, little original forest remains. Much of that is outside formal protected areas and faces the risk of deforestation. These factors create special circumstances for setting conservation priorities — ones common to hotspots in general — but typically not to many conservation priority setting exercises.We mapped the distribution of the remaining habitat for the 189 birds in Rio de Janeiro state that are officially endangered and/or endemic to the Atlantic Forest. Using those habitat maps, we calculated the amount of habitat currently within protected areas for each species. We then prioritized all non-protected parts of the state for their avian conservation value and their potential contribution to a comprehensive protected area system. This analysis identified 10% of the remaining unprotected part of the state as the highest priority for avian conservation. We further highlight specific locations where conservation actions could create a more comprehensive protected area system for the avifauna of Rio de Janeiro state.  相似文献   

16.
Forest degradation deepens around and within protected areas in East Asia   总被引：2，自引：0，他引：2  
Forest degradation in protected areas has been monitored around the world with remote sensing data, but degradation processes undetectable by widely used satellite sensors have been largely overlooked. Increased human pressures and socioeconomic development make forest protection more challenging, particularly for forest ecosystems that lie across national borders because of the differences in national socioeconomic policies and conditions within them. Here with Landsat data, Google Earth images, and field observations, we show that, in two adjacent biosphere reserves across the border of China and North Korea, over one half of primary forest landscapes have been deteriorated by exploitive uses, including seed harvesting and systematic logging. The combined effects of detectable and hidden degradation processes have further damaged forest ecosystems in the core areas in the two biosphere reserves, threatening sustainable biodiversity conservation in the region. It is urgent to develop cross-border collaborative conservation strategies that can help combat both detectable and hidden degradation processes at a regional scale.  相似文献   

17.
Ecosystems services sustain humans all over the world. The unsustainable use of ecosystem services around the world has led to widespread degradation which now threatens human health and livelihoods. Although the maintenance of ecosystem services is often used to justify biodiversity conservation actions, it is still unclear how ecosystem services relate to different aspects of biodiversity and to what extent the conservation of biodiversity will ensure the provision of services. The aim of this study was to find out whether biodiversity priorities, biomes, species richness and vegetation diversity hotspots co-occur in space with ecosystem services. The distribution of the ranges and hotspots of five ecosystem services (surface water supply, water flow regulation, carbon storage, soil accumulation, and soil retention) was assessed in South African biomes. Coincidence, overlap, and correlation analyses were used to assess spatial congruence between ecosystem services and species richness (plants and animals) and vegetation diversity hotspots. The grassland and savanna biomes contained significant amounts of all five ecosystem services. There was moderate overlap and a generally positive but low correlation between ecosystem services hotspots and species richness and vegetation diversity hotspots. Species richness was mostly higher in the hotspots of water flow regulation and soil accumulation than would be expected by chance. The water services showed varying levels of congruence with species richness hotspots and vegetation diversity hotspot. These results indicate that actions taken to conserve biodiversity in South Africa will also protect certain ecosystem services and ecosystem services can be used to strengthen biodiversity conservation in some instances.  相似文献   

18.
To be effective, reserve networks should represent all target species in protected areas that are large enough to ensure species persistence. Given limited resources to set aside protected areas for biodiversity conservation, and competing land uses, a prime consideration for the design of reserve networks is efficiency (the maximum biodiversity represented in a minimum number of sites). However, to be effective, networks may sacrifice efficiency. We used reserve selection algorithms to determine whether collections of existing individual protected areas in Canada were efficient and/or effective in terms of representing the diversity of disturbance-sensitive mammals in Canada in comparison to (1) an optimal network of reserves, and (2) sites selected at random. Unlike previous studies, we restricted our analysis to individual protected areas that met a criterion for minimum reserve size, to address issues of representation and persistence simultaneously. We also tested for effectiveness and efficiency using historical and present-day data to see whether protected area efficiency and/or effectiveness varied over time. In general, existing protected areas did not effectively capture the full suite of mammalian species diversity, nor are most existing protected areas part of a near-optimal solution set. To be effective, Canada’s network of reserves will require at minimum 22 additional areas of >2700 km2. This study shows that even when only those reserves large enough to be effective are considered, protected areas systems may not be representative, nor were they representative at the time of establishment.  相似文献   

19.
The issue of what conservation strategies to apply in agricultural landscape for the most effective protection of biodiversity has been debated for some years. The creation and maintenance of nature reserves is often hampered by both ecological and economic factors, while the ecological effectiveness of agri-environment schemes (AES) is still being queried. Our study examined how the spatial pattern of nature reserves and AES affects the diversity of 25 target species of conservation interest in ditch banks and how this information might be used to develop a strategy resulting in synergy between protected areas and enhanced matrix quality. We studied target species plant diversity on 92 ditch banks under AES and on 102 banks not under such a regime; all of them running parallel to nature reserves. We compared the results with those obtained from a previous study which focused on ditch banks running transverse. On non-AES ditch banks running parallel to nature reserves, there was a significant decline in species richness with increasing distance from the nature reserve while this was not the case for AES ditch banks. The effect of AES differed between the two directions, with a significant effect beyond 200 m in the parallel direction and within 200 m in the transverse direction. Our results indicate that synergy between nature reserves and AES can enhance plant diversity and, since the AES effect was different in different direction due to wind direction and nitrogen input to adjacent fields, location of AES should be chosen carefully.  相似文献   

20.
Given the importance placed on protected areas, determining their effectiveness in representing and maintaining biodiversity is a core issue in conservation biology. Nonetheless, frameworks identifying the breadth of issues associated with this effectiveness, and case studies of how well these are understood in particular regions, remain lacking. In this paper, we provide such a framework and an overview of the current state of knowledge of the ecological effectiveness of protected areas in the United Kingdom. Arguably, better data are available to address such issues in this region than anywhere else in the world. Nonetheless, studies remain scarce and have focussed foremost on the, rather narrow, issue of the effectiveness of management actions on individual sites in order to deliver fixed conservation objectives and discharge statutory responsibilities. Some attention has also been paid to how well the regional collection or portfolio of protected areas performs, particularly in capturing biodiversity features. Work on the extent to which protected areas in the United Kingdom form effective functional networks is in its infancy, but initiatives are under development. We identify some of the questions about the effectiveness of protected areas to which answers need to be known at the site, portfolio and network levels, and how significant progress might be achieved in addressing these.  相似文献   

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