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1.
A central goal of conservation science is to identify the most important habitat patches for maintaining biodiversity on a landscape. Spatial biodiversity patterns are often used for such assessments, and patches that harbor unique diversity are generally prioritized over those with high community similarity to other areas. This places an emphasis on biodiversity representation, but removing a patch can have cascading effects on biodiversity persistence in the remaining ecological communities. Metacommunity theory provides a mechanistic route to the linking of biodiversity patterns on a landscape with the subsequent dynamics of diversity loss after habitat is degraded. Using spatially explicit neutral theory, I focus on the situation where spatial patterns of diversity and similarity are generated by the structure of dispersal networks and not environmental gradients. I find that gains in biodiversity representation are nullified by losses in persistence, and as a result the effects of removing a patch on metacommunity diversity are essentially independent of complementarity or other biodiversity patterns. In this scenario, maximizing protected area and not biodiversity representation is the key to maintaining diversity in the long term. These results highlight the need for a broader understanding of how conservation paradigms perform under different models of metacommunity dynamics.  相似文献   

2.
Costa Rica is recognized as one of the most diverse countries in species and ecosystems, in their terrestrial realm as well as in the marine. Besides this relevance, the country presents a delay on conservation and management of marine and coastal biodiversity, with respect to terrestrial. For 2006, the marine protected surface was 5,208.8 km2, with 331.5 km of coastline, in 20 protected areas. The country has made progress on the conservation priority sites identification for terrestrial and freshwater biodiversity, with few efforts on marine planning. This research presents the analysis and results of the gap identification process, for marine and coastal biodiversity conservation in the protected areas system of Costa Rica. The analysis was built with the spatial information available on the presence and distribution of coastal and marine biodiversity, the establishment of the conservation goals and a threat analysis over the ecological integrity of this biodiversity. The selection of high-priority sites was carried out using spatial optimization techniques and the superposition over the current shape of marine protected areas, in order to identify representation gaps. A total of 19,076 km2 of conservation gaps were indentified, with 1,323 km2 in the Caribbean and 17,753 km2 in the Pacific. Recommendations are aimed at planning and strengthening the marine protected areas system, using the gaps identified as a framework. It is expected that the results of this study would be the scientific base needed for planning and sustainable use of marine biodiversity in the country.  相似文献   

3.
There are now over 100000 protected areas worldwide, covering over 12% of the Earth's land surface. These areas represent one of the most significant human resource use allocations on the planet. The importance of protected areas is reflected in their widely accepted role as an indicator for global targets and environmental assessments. However, measuring the number and extent of protected areas only provides a unidimensional indicator of political commitment to biodiversity conservation. Data on the geographic location and spatial extent of protected areas will not provide information on a key determinant for meeting global biodiversity targets: 'effectiveness' in conserving biodiversity. Although tools are being devised to assess management effectiveness, there is no globally accepted metric. Nevertheless, the numerical, spatial and geographic attributes of protected areas can be further enhanced by investigation of the biodiversity coverage of these protected areas, using species, habitats or biogeographic classifications. This paper reviews the current global extent of protected areas in terms of geopolitical and habitat coverage, and considers their value as a global indicator of conservation action or response. The paper discusses the role of the World Database on Protected Areas and collection and quality control issues, and identifies areas for improvement, including how conservation effectiveness indicators may be included in the database to improve the value of protected areas data as an indicator for meeting global biodiversity targets.  相似文献   

4.
Abstract. Conservation seeks ultimately to protect and maintain biodiversity indefinitely. Most biodiversity features targeted in past conservation planning have been largely aspects of ecological and biogeographical pattern rather than process. However, the persistence of biodiversity can only be ensured through consideration of the ecological and evolutionary processes that underpin biodiversity, as well as its present spatial pattern. This paper identifies spatial surrogates of ecological and evolutionary processes for regional conservation planning in one of the world's biodiversity hotspots, the Cape Floristic Region. We identified six types of spatial components (namely edaphic interfaces, upland–lowland interfaces, sand movement corridors, riverine corridors, upland–lowland gradients and macroclimatic gradients) as surrogates for key processes such as ecological and geographical diversification, and species migration. Spatial components were identified in a GIS using published data and expert knowledge. Options for achieving targets for process components have been seriously compromised by habitat transformation. Between 30 and 75% of the original extent of the spatial components currently remain functional. Options for achieving upland–lowland and macroclimatic gradients are very limited in the lowlands where most of the habitat has been transformed by agriculture. We recommend that future studies place their research on ecological and evolutionary processes in a spatially explicit framework. Areas maintaining adaptive diversification (e.g. environmental gradients, ecotones) or containing historically isolated populations should be identified and protected. The spatial dimensions of eco-logical processes such as drought and fire refugia also need to be determined and such insights incorporated in conservation planning. Finally, connectivity within these areas should be ensured to maintain species migration and gene flow.  相似文献   

5.
Protected areas are considered as an essential strategy to halt the decline of biodiversity. Ecological representation in protected areas is crucial for assessment on the progress toward conservation targets. Although China has established a large number of protected areas since the 1950s, ecological representation of protected areas is poorly understood. Here, we performed the complementarity analysis to evaluate ecological representation of protected areas in China. We used a database of the geographical distribution for 10,396 woody plant species, 2,305 fern species, 406 amphibian species, 460 reptile species, 1,364 bird species, and 590 mammal species from 2,376 counties across China. We identified complementary sets of counties for all species or threatened species of plant and vertebrate species using a complementarity algorithm. We evaluated ecological representation of 3,627 protected areas and discerned conservation gaps by comparing the distribution of protected areas with complementary sets. The results show that the spatially representative and complementary sites for biodiversity are poorly covered, and a fairly large proportion of protected areas is not designed to efficiently represent biodiversity at the national scale. Our methodology can serve as a generic framework for assessment on ecological representation of protected areas at the national scale.  相似文献   

6.
The Convention on Biological Diversity requires that member nations establish protected area networks that are representative of the country's biodiversity. The identification of priority sites to achieve outstanding representation targets is typically accomplished through formal conservation assessments. However, representation in conservation assessments or gap analyses has largely been interpreted based on a static view of biodiversity. In a rapidly changing climate, the speed of changes in biodiversity distribution and abundance is causing us to rethink the viability of this approach. Here we describe three explicit strategies for climate change adaptation as part of national conservation assessments: conserving the geophysical stage, identifying and protecting climate refugia, and promoting cross‐environment connectivity. We demonstrate how these three approaches were integrated into a national terrestrial conservation assessment for Papua New Guinea, one of the most biodiverse countries on earth. Protected areas identified based on representing geophysical diversity were able to capture over 90% of the diversity in vegetation communities, suggesting they could help protect representative biodiversity regardless of changes in the distribution of species and communities. By including climate change refugia as part of the national conservation assessment, it was possible to substantially reduce the amount of environmental change expected to be experienced within protected areas, without increasing the overall cost of the protected area network. Explicitly considering environmental heterogeneity between adjacent areas resulted in protected area networks with over 40% more internal environmental connectivity. These three climate change adaptation strategies represent defensible ways to guide national conservation priority given the uncertainty that currently exists in our ability to predict climate changes and their impacts. Importantly, they are also consistent with data and expertise typically available during national conservation assessments, including in developing nations. This means that in the vast majority of countries, these strategies could be implemented immediately.  相似文献   

7.
Land‐use changes and the expansion of protected areas (PAs) have amplified the interaction between protected and unprotected areas worldwide. In this context, ‘interface processes' (human–nature and cross‐boundary interactions inside and around PAs) have become central to issues around the conservation of biodiversity and ecosystem services. This scientific literature review aimed to explore current knowledge and research gaps on interface processes regarding terrestrial PAs. At first, 3,515 references related to the topic were extracted through a standardized search on the Web of Science and analyzed with scientometric techniques. Next, a full‐text analysis was conducted on a sample of 240 research papers. A keyword analysis revealed a wide diversity of research topics, from ‘pure' ecology to sociopolitical research. We found a bias in the geographical distribution of research, with half the papers focusing on eight countries. Additionally, we found that the spatial extent of cross‐boundary interactions was rarely assessed, preventing any clear delimitation of PA interactive zones. In the 240 research papers we scanned, we identified 403 processes that were studied. The ecological effects of PAs were well documented and appeared to be positive overall. In contrast, the effects of PAs on local communities were understudied and, according to the literature focusing on these, were very variable according to local contexts. Our findings highlight key research advances on interface processes, especially regarding the ecological outcomes of PAs, the influence of human activities on biodiversity, and PA governance issues. In contrast, main knowledge gaps concern the spatial extent of interactive zones, as well as the interactions between local people and conservation actions and how to promote synergies between them. While the review was limited to terrestrial PAs, its findings allow us to propose research priorities for tackling environmental and socioeconomic challenges in the face of a rapidly changing world.  相似文献   

8.
Enormous and increasing loss of biodiversity requires evaluation of surrogate taxa as a tool for conservation biology and new reserve selection, in spite of the fact that this approach has become questionable. The aim of this study was to assess the effect of gradient complexity on species richness and community composition among three taxonomic groups. We compared efficiency of vascular plants to indicate diversity of cryptogams (bryophytes, lichens) and snails in two contrasting habitat types (treeless fens and forests) within the same geographic region. We examined correlation of their species richness (Spearman rank correlation), community composition (Bray–Curtis similarity, Mantel test) and their responses to environmental variables (detrended and canonical correspondence analysis). We also focused on Red List species. We found that spatial congruence among studied taxa was affected by habitat type, however vascular plants were good indicator of snail biodiversity in both habitats. Nevertheless, all significant positive correlations of species richness were associated with the congruence in main environmental gradients. Although there was a consistency in significantly positive cross-taxon correlation in community similarity, the congruence was insufficient for conservation purposes. Furthermore we confirmed the necessity of integration of at-risk species in conservation planning as Red List species were poor indicators for total species richness and vice versa. We suggest the complementation of existing reserve network with small-scale protected areas focused on conservation of at-risk ecosystems, communities or species. In this study vascular plants were not found as a sufficient indicator for fine-filter conservation of other taxa.  相似文献   

9.
Large identifiable landscape units, such as ecoregions, are used to prioritize global and continental conservation efforts, particularly where biodiversity knowledge is inadequate. Setting biodiversity representation targets using coarse large‐scale biogeographic boundaries, can be inefficient and under‐representative. Even when using fine‐scale biodiversity data, representation deficiencies can occur through misalignment of target distributions with such prioritization frameworks. While this pattern has been recognized, quantitative approaches highlighting misalignments have been lacking, particularly for assemblages of mammal species. We tested the efficacy of Australia's bioregions as a spatial prioritization framework for representing mammal species, within protected areas, in New South Wales. We produced an approach based on mammal assemblages and assessed its performance in representing mammal distributions. Substantial spatial misalignment between New South Wales's bioregions and mammal assemblages was revealed, reflecting deficiencies in the representation of more than half of identified mammal assemblages. Using a systematic approach driven by fine‐scale mammalian data, we compared the efficacy of these two frameworks in securing mammalian representation within protected areas. Of the 61 species, 38 were better represented by the mammalian framework, with remaining species only marginally better represented when guided by bioregions. Overall, the rate at which mammal species were incorporated into the protected area network was higher (5.1% ± 0.6 sd) when guided by mammal assemblages. Guided by bioregions, systematic conservation planning of protected areas may be constrained in realizing its full potential in securing representation for all of Australia's biodiversity. Adapting the boundaries of prioritization frameworks by incorporating amassed information from a broad range of taxa should be of conservation significance.  相似文献   

10.
Ecuador has the largest number of species by area worldwide, but also a low representation of species within its protected areas. Here, we applied systematic conservation planning to identify potential areas for conservation in continental Ecuador, with the aim of increasing the representation of terrestrial species diversity in the protected area network. We selected 809 terrestrial species (amphibians, birds, mammals, and plants), for which distributions were estimated via species distribution models (SDMs), using Maxent. For each species we established conservation goals based on conservation priorities, and estimated new potential protected areas using Marxan conservation planning software. For each selected area, we determined their conservation priority and feasibility of establishment, two important aspects in the decision-making processes. We found that according to our conservation goals, the current protected area network contains large conservation gaps. Potential areas for conservation almost double the surface area of currently protected areas. Most of the newly proposed areas are located in the Coast, a region with large conservation gaps and irreversible changes in land use. The most feasible areas for conservation were found in the Amazon and Andes regions, which encompass more undisturbed habitats, and already harbor most of the current reserves. Our study allows defining a viable strategy for preserving Ecuador''s biodiversity, by combining SDMs, GIS-based decision-support software, and priority and feasibility assessments of the selected areas. This approach is useful for complementing protected area networks in countries with great biodiversity, insufficient biological information, and limited resources for conservation.  相似文献   

11.
陈红  欧小杨  吕英烁  李晓溪  郑曦 《生态学报》2024,44(12):5128-5139
气候变化通过改变湿地水文过程等影响湿地的空间分布,城市化进程加剧了湿地破碎化程度并导致湿地生境退化,构建连续的湿地生态保护网络体系有利于应对气候变化和城市发展带来的负面影响、提高生物多样性保护水平。北京市现有湿地空间分布呈现斑块面积小、破碎化程度高等特点,为优化湿地保护区格局并应对气候变化和城市发展对北京市湿地生物多样性的影响,基于系统保护规划方法,以Marxan作为空间优化模型,结合PLUS模型和MaxEnt模型,模拟预测北京市湿地优先保护格局、识别湿地保护空缺并构建湿地分级保护区格局。研究表明:2020年北京市湿地存在80.15km2的保护空缺、2035年和2050年优化后湿地保护区占比分别为87.54%和85.95%,在满足本研究预设的生物多样性保护目标的前提下符合北京市湿地保护规划对湿地保护率的要求。为最优化资源分配,综合时空变化对湿地保护区空间分布的影响,构建了湿地分级保护区格局,将湿地保护区分为湿地永久保护区、湿地一级临时保护区和湿地二级临时保护区三个等级,以期为北京市分期建设湿地保护区、优化湿地生态保护网络体系和保护湿地生物多样性提供依据。  相似文献   

12.
Representativeness is a desirable property of conservation networks. In this paper an attempt is made to assess the efficiency of current conservation networks in Portugal in representing vertebrates (reptiles and amphibians) and plants (gymnosperms, pteridophytes and bryophytes). It was found that whilst the protected areas do not sample all species in the database they provide a better result than choosing areas at random. For the goal of maximizing representation of taxa per unit area hotspots and complementarity performed better. A pattern of over-representation of vertebrates in relation to lower plants was discovered among selected conservation areas in Portugal suggesting that charismatic organisms with large home ranges may not always be the most appropriate surrogates for biodiversity when representativeness is sought. When trying to fill the gaps in current protected areas with additional areas only complementarity performed better than choosing areas at random. Both rarity and richness hotspots gave worse results. Opportunistic administrative criteria such as supplementing the PAS with other conservation areas (CORINE Biotopes) without taking into account their contribution to a representation goal was nearly half as good as choosing areas at random. The results recall for the need of explicit goals and accountable methods in area selection for conservation and reinforce the role of complementarity for finding additional areas to protected areas when limited resources are available for ‘in situ’ conservation.  相似文献   

13.
Collective properties of biodiversity, such as beta diversity, are suggested as complementary measures of species richness to guide the prioritisation and selection of important biodiversity areas in regional conservation planning. We assessed variation in the rate of plant species turnover along and between environmental gradients in KwaZulu-Natal, South Africa using generalised dissimilarity modelling, in order to map landscape levels of floristic beta diversity. Our dataset consisted of 434 plots (1000 m2) containing 997 grassland and savanna matrix species. Our model explained 79 % of the null deviance observed in floristic dissimilarities. Variable rates of turnover existed along the major environmental gradients of mean annual temperature, median rainfall in February, and soil cation exchange capacity, as well as along gradients of geographical distance. Beta diversity was highest in relatively warm, drier summer regions and on dystrophic soils. Areas of high beta diversity identify areas that should be included in conservation plans to maximise representation of diversity and highlight areas best suited to protected area expansion. Biome transition areas in high beta diversity areas may be susceptible to climate variability. Including beta diversity turnover rates in regional conservation plans will help to preserve evolutionary and ecological processes that create and maintain diversity.  相似文献   

14.
Marine protected areas (MPAs) can be an effective tool for marine biodiversity conservation, yet decision-makers usually have limited and biased datasets with which to make decisions about where to locate MPAs. Using commonly available abiotic and biotic datasets, I asked how many datasets are necessary to achieve robust patterns of conservation importance. I applied a decision support tool for marine protected area design in two regions of British Columbia, Canada, and sequentially excluded the datasets with the most limited geographic distribution. I found that the reserve selection method was robust to some missing datasets. The removal of up to 15 of the most geographically limited datasets did not significantly change the geographic patterns of the importance of areas for conservation. Indeed, including abiotic datasets plus at least 12 biotic datasets resulted in a spatial pattern similar to including all available biotic datasets. It was best to combine abiotic and biotic datasets in order to ensure habitats and species were represented. Patterns of clustering differed according to whether I used one set alone or both combined. Biotic datasets served as better surrogates for abiotic datasets than vice versa, and both represented more biodiversity features than randomly selected reserves. These results should provide encouragement to decision-makers engaged in MPA planning with limited spatial data.  相似文献   

15.
Costa Rica has one of the greatest percentages (26%) of protected land in the world. The National Protected Areas System (NPAS) of Costa Rica was established in 1976 and currently includes >190 protected areas within seven different protection categories. The effectiveness of the NPAS to represent species, populations, and areas with high species richness has not been properly evaluated. Such evaluations are fundamental to understand what is necessary to strengthen the NPAS and better protect biodiversity. We present a novel assessment of NPAS effectiveness in protecting mammal species. We compiled the geographical ranges of all terrestrial Costa Rican mammals then determined species lists for all protected areas and the estimated proportion of each species’ geographic range protected. We also classified mammal species according to their conservation status using the IUCN Red List of Threatened Species. We found almost complete representation of mammal species (98.5%) in protected areas, but low relative coverage (28.3% on average) of their geographic ranges in Costa Rica and 25% of the species were classified as underprotected according to a priori representation targets. Interestingly, many species-rich areas are not protected, and at least 43% of cells covering the entire country are not included in protected areas. Though protected areas in Costa Rica represent species richness well, strategic planning for future protected areas to improve species complementarity and range protection is necessary. Our results can help to define sites where new protected areas can have a greater impact on mammal conservation, both in terms of species richness and range protection.  相似文献   

16.
17.
Methods for establishing biodiversity conservation priorities are urgently required, as the number of species and habitats that are threatened increases relative to the material resources available for their conservation. The identification of priority areas demands the integration of biophysical data on ecosystems together with social data on human pressures and planning opportunities. But comprehensive and reliable data are rarely available to demarcate where the need for action is most urgent and where the benefits of conservation strategies can be maximized. Strategic conservation initiatives cannot wait for the creation of comprehensive databases. In order to fill the missing data gaps, the combined knowledge of local and technical experts can be used. This study presents a collaborative geographic information system (GIS) method for integrating the knowledge of local and technical experts with existing spatial environmental data to establish priority areas for biodiversity conservation. Procedures for structuring and framing the discussions, establishing assessment criteria, integrating knowledge with data, and building consensus are incorporated into the method. The method provides a novel cooperative mechanism to aid spatial knowledge management and inclusive biodiversity planning.  相似文献   

18.
中国国家重点保护野生植物的地理分布特征   总被引:9,自引:0,他引:9  
珍稀濒危野生植物作为生物多样性的重要组成部分,是保护生物学研究的核心内容之一.有关濒危物种分布区的研究对于生物多样性保护理论和濒危机制的探讨具有重要意义.本文基于文献资料和标本记录,以《国家重点保护野生植物名录》所列物种(包括即将发布的物种)为研究对象,从全国尺度上对我国保护植物的区系成分组成以及地理分布特征进行了系统分析.结果表明:1)我国国家重点保护植物共计2 177种,隶属于130个科、484个属;2)植物区系成分复杂多样,既具有明显的热带性质,起源古老,同时也有明显的温带过渡性,且特有成分丰富;3)水平地理分布极不均匀,主要集中分布在西南地区和台湾,其中云南、四川、广西、西藏、贵州、台湾为保护植物分布的热点地区;4)垂直分布范围很广,主要集中于800~1 600 m的低山和中山的海拔范围内,海拔梯度呈现单峰规律.本研究将为我国生物多样性优先保护区的确定和生物多样性保护政策的制定提供理论依据与参考.  相似文献   

19.
In the face of accelerating biodiversity loss it is more important than ever to identify important areas of biodiversity and target limited resources for conservation. We developed a method to identify areas of important plant diversity using known species’ distributions and evaluations of the species importance. We collated distribution records of vascular plants and developed a scoring method of spatial prioritisation to assign conservation value to the island of Ireland at the hectad scale (10 km × 10 km) and at the tetrad scale (2 km × 2 km) for two counties where sufficient data were available. Each plant species was assigned a species conservation value based on both its conservation status and distribution in Ireland. For each cell, the species conservation values within the cell were summed, thereby differentiating between areas of high and low conservation value across the landscape. Areas with high conservation value represent the most important areas for plant conservation.The protected area cover and the number of species present in these important areas were also examined by first defining threshold values using two different criteria. Species representation was high in the important areas; the identified important areas of plant diversity maintained high representation of species of conservation concern and achieved high species representation overall, requiring a low number of sites (<8%) to do so. The coincidence of protected areas and important areas for plant diversity was found to be low and while some important areas of plant diversity might benefit from the general protection afforded by these areas, our research highlights the need for conservation outside of protected areas.  相似文献   

20.
If conservation of biodiversity is the goal, then the protected areas network of the continental US may be one of our best conservation tools for safeguarding ecological systems (i.e., vegetation communities). We evaluated representation of ecological systems in the current protected areas network and found insufficient representation at three vegetation community levels within lower elevations and moderate to high productivity soils. We used national-level data for ecological systems and a protected areas database to explore alternative ways we might be able to increase representation of ecological systems within the continental US. By following one or more of these alternatives it may be possible to increase the representation of ecological systems in the protected areas network both quantitatively (from 10% up to 39%) and geographically and come closer to meeting the suggested Convention on Biological Diversity target of 17% for terrestrial areas. We used the Landscape Conservation Cooperative framework for regional analysis and found that increased conservation on some private and public lands may be important to the conservation of ecological systems in Western US, while increased public-private partnerships may be important in the conservation of ecological systems in Eastern US. We have not assessed the pros and cons of following the national or regional alternatives, but rather present them as possibilities that may be considered and evaluated as decisions are made to increase the representation of ecological systems in the protected areas network across their range of ecological, geographical, and geophysical occurrence in the continental US into the future.  相似文献   

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