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1.
Southeast Asia experiences one of the highest rates of deforestation in the tropics due to agricultural expansion, logging, habitat fragmentation and urbanization, which are expected to result in species declines and extinctions. In particular, growing global demands for food, biofuel and other commodities are driving the rapid expansion of oil palm and paper-and-pulp industries at the expense of lowland dipterocarp forests, further jeopardizing Southeast Asian forest biotas. We synthesize recent findings on the effects of land-use changes on plants, invertebrates, vertebrates and ecosystem functioning/services in Southeast Asia. We find that species richness and abundance/density of forest-dependent taxa generally declined in disturbed compared to mature forests. Species with restricted ranges and those with habitat and foraging specialization were particularly vulnerable. Forest loss also disrupted vital ecosystem services (e.g. crop pollination). Long-term studies are needed to understand biotic sustainability in regenerating and degraded forests, particularly in the context of the synergistic or additive effects of multiple agents of biodiversity loss (e.g. invasive species and climate change). The preservation of large tracts of mature forests should remain the principal conservation strategy in the tropics. In addition, reforestation and reintroductions of native species, as well as improved connectivity among forest patches could enhance the conservation value of forest remnants in human-dominated landscapes.  相似文献   

2.
Invertebrates play important roles in ecosystem functioning, but with the decline in biodiversity worldwide, it has become increasingly evident that our knowledge of invertebrate diversity distributions and of how to adequately integrate many invertebrates into conservation strategies is insufficient. We analyzed congruence between patterns of total as well as of endemic species richness of twelve invertebrate taxa across Europe and compared these patterns to those of so far predominantly studied vertebrates and plants. Coarse-scale centers of high collective diversity were identified, all in southern European regions. However, the strength of covariation between diversity patterns strongly depended on the respective taxa, with ground beetles emerging as one of the invertebrate taxa significantly reflecting endemism and total species richness distributions of many invertebrates, vertebrates and plants. Plants and ants showed similarly strong cross-taxon correlations. In contrast, correlations of vertebrates with invertebrates were in part less strong, questioning whether conservation strategies based on the former adequately account for diversity of invertebrates as a whole. Moreover, as the potential impact of environmental factors on diversity distributions varies among taxa, future climate change might affect relationships between richness patterns of different taxa. Our findings draw attention to the necessity of incorporating invertebrates, represented for instance by the highly diverse ground beetles, into national and international conservation decisions. They also highlight the importance of individual countries in maintaining European biodiversity and the responsibility of these countries for specific invertebrate taxa within international conservation frameworks, emphasizing the need for adequate consideration of invertebrates in the implementation of conservation actions.  相似文献   

3.
Birds are among the most widely studied organisms on earth and represent an important indicator group for learning about the effects of climate change – particularly in regard to the effects of climate change on tropical ecosystems. In this review, we assess the potential impacts of climate change on tropical birds and discuss the factors that affect species’ ability to adapt and survive the impending alterations in habitat availability. Tropical mountain birds, species without access to higher elevations, coastal forest birds, and restricted-range species are especially vulnerable. Some birds may be especially susceptible to increased rainfall seasonality and to extreme weather events, such as heat waves, cold spells, and tropical cyclones. Birds that experience limited temperature variation and have low basal metabolic rates will be the most prone to the physiological effects of warming temperatures and heat waves. Mostly unknown species’ interactions, indirect effects, and synergies of climate change with other threats, such as habitat loss, emerging diseases, invasive species, and hunting will exacerbate the effects of climate change on tropical birds. In some models habitat loss can increase bird extinctions caused by climate change by 50%. 3.5 °C surface warming by the year 2100 may result in 600–900 extinctions of land bird species, 89% of which occur in the tropics. Depending on the amount of future habitat loss, each degree of surface warming could lead to approximately 100–500 additional bird extinctions. Protected areas will be more important than ever, but they need to be designed with climate change in mind. Although 92% of currently protected areas are likely to become climatically unsuitable in a century, for example only 7 or 8 priority species’ preferred climatic envelopes are projected to be entirely lost from the African Important Bird Area network. Networks of protected areas need to incorporate extensive topographical diversity, cover wide elevational ranges, have high connectivity, and integrate human-dominated landscapes into conservation schemes. Most tropical bird species vulnerable to climate change are not currently considered threatened with extinction, often due to lack of knowledge; systematically and regularly gathering information on the ecology, and current and future distributions of these species is an urgent priority. Locally based, long-term tropical bird monitoring and conservation programs based on adaptive management are essential to help protect birds against climate change.  相似文献   

4.
Limestone karsts on tropical land masses are considered de facto habitat islands due to their isolation from one another by non-calcareous substrata; this spatial configuration limits gene flow and induces high levels of species endemism. Apart from their biological importance, karsts are also highly valued for the ecosystem services and resources they provide if left intact. Unfortunately, conservation planning for karsts has generally lacked scientific basis. Ideally, factors affecting the richness and distribution of karst-endemic taxa should be incorporated into quantitative guidelines for karst reserve selection. Using land snail data from 43 different karstic towers in Malaysia, we: (1) identified biogeographical factors (i.e., area, isolation, surrounding soil type and geological age) hypothesized to influence endemic richness; and (2) investigated how species distributions varied among karsts in different regions. Generalized linear mixed-effect models revealed the relatively important effects of surrounding soil type and karst area on land snail endemism; the most parsimonious model contributed to 63.6% of the Akaike’s Information Criterion weight and explained over 18% of the deviance in karst-endemic richness (of which 10.0% was explained by surrounding soil type). Non-metric multi-dimensional scaling indicated that karsts in different regions of Malaysia had distinct malacofaunas. Therefore, conservation planners should take into account karst size, surrounding soil type and the influence of geographic barriers to maximize the protection of land snails and possibly other karst-endemic taxa, which are increasingly threatened by quarrying throughout Southeast Asia.  相似文献   

5.
A comprehensive understanding of species phenological responses to global warming will require observations that are both long-term and spatially extensive. Here we present an analysis of the spring phenological response to climate variation of twelve taxa: six plants, three birds, a frog, and two insects. Phenology was monitored using standardized protocols at 176 meteorological stations in Japan and South Korea from 1953 to 2005, and in some cases even longer. We developed a hierarchical Bayesian model to examine the complex interactions of temperature, site effects, and latitude on phenology. Results show species-specific variation in the magnitude and even in the direction of their responses to increasing temperature, which also differ from site-to-site. At most sites the differences in phenology among species are forecast to become greater with warmer temperatures. Our results challenge the assertion that trends in one geographic region can be extrapolated to others, and emphasize the idiosyncratic nature of the species response to global warming. Field studies are needed to determine how these patterns of variation in species response to climate change affect species interactions and the ability to persist in a changing climate.  相似文献   

6.
Introduced species may impact native species and communities in many ways. One which has received relatively little attention is by serving as resources for natives, thereby altering their ecology. We address such impacts on the California butterfly fauna as currently understood. Eighty-two of California's approximately 236 butterfly species (34%) are reported as ovipositing or feeding on introduced plant taxa. Many more utilize introduced plants as nectar sources. Interactions with introduced plant taxa are not distributed evenly among butterfly species. Alpine and desert butterflies interact with relatively few introduced plants because few exotic plant species have reached and successfully colonized these habitats. Other California butterfly species are specialists on particular plant families or genera with no exotic representatives in California and have thus far failed to recognize any introduced plants as potential foodplants. Some California butterflies have expanded their geographic ranges and/or extended their flight seasons by feeding on exotic plants. However, negative impacts of exotic plant species can also occur. At least three of the state's butterfly species currently lay eggs on introduced taxa that are toxic to larvae. Impacts of introduced plant taxa on California's butterflies are expected to increase as both habitat conversion and alien introductions accelerate.  相似文献   

7.
Deforestation is a major threat to the conservation of biodiversity, especially within global centers of endemism for plants and animals. Elevation, the major environmental gradient in mountain regions of the world, produces a rapid turnover of species, where some species may exist only in narrow elevational ranges. We use newly compiled datasets to assess the conservation impact of deforestation on threatened trees across an elevational gradient within the Eastern Arc Mountains of Tanzania. The Eastern Arc has suffered an estimated 80% total loss in historical forest area and has lost 25% of forest area since 1955. Forest loss has not been even across all elevations. The upper montane zone (>1800 m) has lost 52% of its paleoecological forest area, 6% since 1955. Conversely, the submontane habitat (800–1200 m) has lost close to 93% of its paleoecological extent, 57% since 1955. A list of 123 narrowly endemic Tanzanian Eastern Arc tree taxa with defined and restricted elevational ranges was compiled and analyzed in regard to mountain block locations, elevational range, and area of forest within each 100 m elevational band. Half of these taxa have lost more than 90% of paleoecological forest habitat in their elevational range. When elevational range is considered, 98 (80%) of these endemic forest trees should have their level of extinction threat elevated on the IUCN Red List. Conservation efforts in montane hotspots need to consider the extent of habitat changes both within and across elevations and target conservation and restoration efforts throughout these ecosystems’ entire elevational ranges.  相似文献   

8.
The Tibetan Plateau of China is uniquely vulnerable to the global climate change and anthropogenic disturbances. As soil bacteria exert a considerable influence on the ecosystem function, understanding their response to different climates and land-use types is important. Here, we characterized the bacterial community composition and diversity across three major ecosystems (cropland, forest, and grassland) in the Sygera Mountains of Tibet, along a typical elevational gradient (3 300-4 600 m). The abundance of taxa that preferentially inhabit neutral or weak alkaline soil environments (such as Actinobacteria, Thermoleophilia, and some non-acidophilus Acidobacteria) was significantly greater in the cropland than in the forest and grassland. Furthermore, the diversity of soil bacterial communities was also significantly greater in the cropland than in the forest and grassland. We observed a unimodal distribution of bacterial species diversity along the elevation gradient. The dominant phyla Acidobacteria and Proteobacteria exhibited consistent elevational distribution patterns that mirrored the abundance of their most abundant classes, while different patterns were observed for Acidobacteria and Proteobacteria at the class level. Soil pH was the primary edaphic property that regulated bacterial community composition across the different land-use types. Additionally, soil pH was the main factor distinguishing bacterial communities in managed soils (i.e., cropland) from the communities in the natural environments (i.e., forest and grassland). In conclusion, land use (particularly anthropogenic disturbances such as cropping) largely controlled soil environment, played a major role in driving bacterial community composition and distribution, and also surpassed climate in affecting bacterial community distribution.  相似文献   

9.
Hunting is one of the greatest conservation challenges facing tropical wildlife. Wildlife in Indian tropical forests are vulnerable to hunting, although data on hunting impacts from the region are limited. We use a meta-analysis of 143 hunting studies from India to identify the species and geographic regions most at risk, and to assess their legal protection. We found evidence of hunting in 114 mammal species, with larger-bodied mammals being particularly vulnerable. Although 75% of all studies focused on mammals, few actually quantified hunting impacts. Further, among studies of all terrestrial vertebrates where hunting was mentioned, only 6% focused exclusively on hunting. With further research, we expect that the suite of species known to be exploited by hunters will increase. We conclude that the Eastern Himalaya and Indo-Myanmar biodiversity-hotspot complex is particularly vulnerable to hunting. Quantitative studies of hunting impacts are urgently needed across India, especially in this biodiversity-hotspot complex.  相似文献   

10.
Amphibian declines and extinctions are a worldwide concern. Conservation priorities for amphibians should target threatened taxa (taxonomic targets) and regions with high levels of species endemism (geographical targets). Does published research on amphibian conservation reflect the global taxonomic and geographic priorities? I surveyed six years (2000-2005) of 10 conservation and herpetological journals (Amphibia-Reptilia, Animal Conservation, Applied Herpetology, Biodiversity and Conservation, Biological Conservation, Conservation Biology, Copeia, Herpetologica, Journal of Herpetology and Oryx), and analyzed all articles on amphibians. Attention indexes were calculated for orders, threatened species and biogeographic realms. I also examined how well research from tropical developing nations (with high levels of richness and endemism) are represented in the international literature. Attention indexes results show that the most studied amphibian order is Caudata, whereas Gymnophiona is the least studied one. The same trend is observed for threatened species, with threatened Caudata species receiving proportionally more attention than threatened Anura and Gymnophiona. The biogeographic realms that receive most attention by amphibian conservationists are: Oceania, Nearctic and Palearctic. However, the Neotropical, Afrotropical and Indomalayan are the regions with higher species diversity. Forty-one countries contributed articles, but the majority of amphibian conservation research is conducted by North American and western European researchers. There is urgent need for capacity building in tropical developing nations. Amphibians are more threatened and are declining more rapidly than either birds or mammals. However, amphibian conservation is still misplacing its focus in lower-biodiversity regions and non-threatened species. If such trends are not changed, the consequences for the persistence of amphibians worldwide may be dire.  相似文献   

11.
Endemic species are not a uniform group in terms of range size, habitat preferences, and ecological plasticity. Based on a recent inventory of endemic vascular plant species in Austria, we analysed distribution patterns, altitudinal distribution and habitat preferences of endemic species and analysed the correlation of range size and niche breadth. The inventory includes 103 vascular plant taxa (species and subspecies) endemic to Austria.Grid cells (cell size ca. 35 km2) with highest taxon numbers (max. 25 taxa) are limited to the Northeastern Calcareous Alps, whereas highest numbers of acidophilous endemics occur in the easternmost high-mountain chains of the Central Alps. The majority of endemics (61 taxa; 59.2%) are found on calcareous bedrock, 6 taxa (5.8%) on intermediate substrates, and 29 (28.2%) on siliceous bedrock. The range size of endemic vascular plant taxa is strongly skewed towards very narrow distributions – 45 taxa are restricted to <20 grid cells. Average range sizes differ markedly between endemics of different broad habitat types, endemics of habitats with limited and patchy distribution (serpentine vegetation, dry grassland) having the smallest ranges.The altitudinal distribution of endemic plant taxa peaks at high altitudes, in the subalpine and lower alpine altitude belt. Below the tree line, endemics predominantly colonize extra- and azonal dry or wet habitats, whereas above the tree line, zonal alpine grassland and azonal vegetation types (scree, rocks, snowbeds) are equally essential to the endemic flora. Niche breadth of endemics is positively, however moderately, correlated with range size. This correlation is stronger for the altitudinal distribution than for the number of habitats colonized.The distribution patterns and ecology of endemics differ considerably from overall biodiversity patterns and must be addressed appropriately in conservation strategies. Small niche-breadths and the specific habitat requirements of endemics of very localized distribution render these taxa highly vulnerable to climate change.  相似文献   

12.
El Nino events and associated droughts adversely affect freshwater resources on islands in the tropical Pacific region. Particularly vulnerable are low-lying atolls because rainwater collection is the main freshwater source on such islands. During El Nino-related droughts, water can be drawn only from the limited freshwater lenses beneath the islands. If drought conditions such as these intensify, the depletion of freshwater resources could affect the habitability of atolls. Average climate change inthe Pacific region from increased anthropogenic carbon dioxide in a global coupled climate model resembles present-day El Nino conditions as well as the decadal time-scale sea surface temperature and precipitation anomalies observed during the 1980s and early 1990s. These anomalies are a consequence of greater warming of sea surface temperatures in the eastern equatorial Pacific than over the western Pacific warm pool with increased carbon dioxide in the climate model. Attendant increases in precipitation in the central equatorial Pacific are also accompanied by precipitation decreases in the northern and southern tropical Pacific (roughly 5 °N to 15°N and 5°S to 15°S), as well as in the Australasian and eastern Indian Ocean regions. Associated effects in the midlatitude North Pacific also resemble El Nino conditions and the decadal time-scale signals from the 1980s. Future possible increases of drought conditions in certain tropical Pacific regions, as indicated by the climate model results, could limit the sustainability of atoll populations in those regions, causing migration and increased urbanization, with all the attendant problems, on larger high islands with more stable water supplies.  相似文献   

13.
基于ISI-MIP推荐的5个气候模式在4个RCP情景下的模拟结果,筛选21世纪末全球升温最接近1.5℃和2.0℃的气候数据,运用作物模型DSSAT,模拟升温1.5℃和2.0℃背景下中国玉米产量相对于基准时段1985-2006年的变化,揭示了1.5℃与2.0℃升温背景下中国玉米产量变化的空间分布。结果表明:升温2.0℃背景下玉米减产风险明显高于升温1.5℃,未来升温2.0℃背景下中国玉米减产面积比升温1.5℃背景下多6.2%,升温1.5℃和2.0℃背景下中国玉米平均减产幅度分别为3.7%和11.5%;从空间分布来看,升温1.5℃与2.0℃背景下未来中国玉米产量变化在区域分布上大致相似,但未来玉米增产和减产的面积和幅度不尽相同,在北方与西南玉米种植区都有一定的增产区域,其它区域大多以减产为主,其中西北部玉米种植区减幅最大;1.5℃升温背景下北方大部分地区气候条件对玉米生长有利,2.0℃升温背景下北方地区玉米减产也不明显,说明从近期到未来一段时间内,将全球升温控制在1.5℃以内,北方地区玉米仍具有一定增产潜力。  相似文献   

14.
The rise of extinction rates associated with human activities has led to a growing interest in identifying extinction-prone taxa and extinction-promoting drivers. Previous work has identified habitat alterations and invasive species as the major drivers of recent bird extinctions. Here, we extend this work to ask how these human-driven impacts differentially affect extinction-prone taxa, and if any specific driver promotes taxonomic homogenization of avifauna. Like most previous studies, our analysis is based on global information of extinction drivers affecting threatened and extinct bird species from the IUCN Red List. Unlike previous studies, we employ a multivariate statistical framework that allows us to identify the main gradients of variation in extinction drivers. By using these gradients, we show that bird families with the highest extinction risk are primarily associated with threats posed by invasive species, once species richness and phylogeny are taken into account. As expected, the negative impact of invasive species was higher on island species, but our results also showed that it was particularly high in those species with small distribution ranges. On the other hand, mainland species and island species with large ranges tended to be affected by habitat destruction. Thus the impacts of invasive species promote the process of taxonomic homogenization among islands and between islands and continents. Consequently, introduced species may increase biotic homogenization not only directly, as generally believed, but also indirectly through their disproportional impact on endemic species imperilment.  相似文献   

15.
阐述了气候变化对我国森林地理分布格局、物候期、生物多样性、森林结构及生产力的影响。研究表明,气候变化对我国主要造林树种地理分布的影响多发生在气候交错地带,少部分发生在适宜分布区域,树种分布可能向北或向高海拔地区移动;不同区域树种物候期推迟或提前,原区域的适宜物种减少,新物种随气候变化迁入;气候变化基本未改变我国森林第一性生产力的地理分布格局,但群落生物量水平将有所提高,不同树种森林结构变化不同。通过采取积极的适应性措施可降低气候变化的不利影响。  相似文献   

16.
The future of tropical species in secondary forests: A quantitative review   总被引:1,自引:0,他引:1  
Deforestation and degradation of tropical old-growth forests has the potential to cause catastrophic species extinctions. In this review, we assess whether regenerating secondary forests (SF) can support species typically found in old-growth forest (OG) and so prevent extinctions. We review 65 studies that compare faunal diversity in SF and corresponding OG, and compare the similarity of species composition both within and between these two forest types using the Sorensen, Morisita-Horn and Sorensen-Chao indices. Comparisons between traditional similarity indices and Sorensen-Chao, which minimizes sampling biases, indicated that limited sampling effort consistently reduced apparent similarity between SF and OG and that similarity between SF and OG is actually higher than previously appreciated. Similarity, which ranges from 0 to 1, varied from 0.49 to 0.92 between replicate OG sites and was correlated with similarity between SF and OG. This correlation might be an artefact of variation among studies in sampling effort, especially for vertebrates where small samples reduce apparent similarity across all comparisons, as well as a real effect of variation among studies in landscape heterogeneity and the presence of species with patchy distributions. Therefore, similarity between SF and OG cannot be interpreted without an understanding of background variation in OG. Similarity between different SF sites provided no evidence that disturbance specialists dominate SF. Similarity to OG increased rapidly with SF age; when SF was contiguous with OG; when SF was growing in small clearings; and after low intensity land uses including clearing only, shifting agriculture and tree plantations. This describes the most frequently observed tropical SF; isolated from roads and on hilly terrain unsuitable for mechanized agriculture. Thus, our analyses indicate that tropical SF can play an important role in biodiversity conservation particularly when OG forests are nearby. An important caveat remains, however. Abundance, geographic range and levels of habitat specialization are often related. Widespread, abundant, habitat generalists might dominate similarity analyses even when relatively rare OG specialists are present. Additional species-level analyses of habitat specialization will be needed before the conservation value of tropical SF is fully understood.  相似文献   

17.
In South-East Asia patterns of forest loss can predict the number of threatened birds. On the oceanic islands of Wallacea, small-scale agriculture, rather than commercial logging, is the main cause of forest loss and conversion, but few studies have directly examined their responses to land use. In 2001, I studied the birds of primary forest and anthropogenic gardens on the well-forested, and remote, Damar Island (198 km2) in the Banda Sea. Furthermore, I examined broad changes to the islands bird fauna by comparing baseline bird lists obtained in the 19th century with 2001 data. The conversion of primary forest to garden resulted in substantial changes in avifaunal composition, and to the abundance of individual bird species, particularly to frugivorous and globally restricted-range species. Of 15 common birds, four were significantly more abundant in primary forest (blue-tailed imperial pigeon Ducula concinna, northern fantail Rhipidura rufiventris, golden whistler Pachycephala pectoralis and red-chested flowerpecker Dicaeum maugei) and one (scaly-breasted honeyeater Lichmera squamata) was more abundant in garden habitat. Incidental observations provided further evidence that many forest specialists (including the island endemic Damar flycatcher Ficedula henrici) rarely, if ever, used garden habitats notwithstanding its relative proximity. The number of resident birds recorded in 2001 (39) was similar to the 1890s (38), but six forest-dependent passerines were extirpated between samples. These losses are associated with the conversion of 25% of the primary forest to modified habitat since the 1890s, but given the sparse species and environmental change data available it is impossible to definitively pinpoint this as the only cause underlying the species losses. This study demonstrates that remote and relatively well-forested islands are not immune to the threatening processes impacting bird populations elsewhere in South-East Asia.  相似文献   

18.
Statistical models that describe species-environmental relationships are important components within many wildlife conservation strategies. These models are typically developed from studies conducted on small geographic scales (hundreds of square kilometres), representing a relatively small range in environmental conditions. Such local models from local studies are often then extrapolated to predict the suitability of other unsampled regions. The value of many models would be increased by considering larger-scale processes that might be structuring spatial patterns across species distributions. We examined home-range habitat selection by burrowing owls throughout the mixed prairie grassland region of western Canada (180,000 km2) to determine whether owl selection for biotic factors changes along abiotic gradients. Specifically, we classified 37 explanatory variables into five categories (geography, grassland fragmentation, land-use, soil, and climate), created models for each set of variables, and evaluated the predictive ability of each model. We then examined interaction effects to determine if the relationship between land cover variables and the probability of owl home-range selection varied within large-scale abiotic criteria. Our results showed that soil and climate produce the most predictive models of burrowing owl home-range selection and create unique environmental conditions for owls which are independent of land cover at this scale. This study provides new insight into burrowing owl habitat requirements, and strengthens the case for considering large-scale abiotic gradients when prioritizing areas for species conservation.  相似文献   

19.
Current approaches in terrestrial biodiversity conservation focus predominantly on plants and vertebrates. While these groups account for less than 4% of the estimated global species richness, it is commonly argued that especially the species richness in higher plants is a suitable indicator of overall biodiversity. We tested this assumption, investigating species richness and equitability patterns in three highly species-rich insect families and their links with the vegetation and other environmental factors. Vegetation surveys were combined with pitfall and light trapping to establish the α-diversity of ground beetles, geometrid moths and arctiid moths on 48 plots at varying altitudes between Beijing and the Inner Mongolian Plateau. Soil pH and nutrient status were also recorded. The α-diversity patterns in the three insect families were non-congruent, and links with phytodiversity were weak. The spatial α-diversity patterns in each of the three insect families were significantly correlated with the species density of individual plant families. These links varied between the three insect taxa and were mostly negative in moths. Furthermore, geometrid moth diversity decreased with increasing elevation and decreasing soil pH. Strongly diverging α-diversity patterns across different insect taxa illustrate that it is impossible to find a simple surrogate representing cross-taxon diversity for these highly diverse groups. Furthermore, phytodiversity and vegetation composition appear to play a limited role in governing insect diversity patterns. These results underline the significant risk that current plant-focused approaches in terrestrial biodiversity conservation are inadequate in addressing the conservation needs of the vast majority of species on earth.  相似文献   

20.
The establishment and maintenance of a system of protected areas is central to regional and global strategies for the conservation of biodiversity. The current global trend towards human population growth and widespread environmental degradation means that such areas are becoming increasingly isolated in fragmented habitat islands. In regions in which this process is well advanced a high proportion of species are thus predicted to have become restricted to protected areas. Here using uniquely detailed datasets for Britain, a region with close to the global level of percentage coverage by statutory protected areas, we determine the extent of restriction of Red List vascular plant species of conservation concern to these areas. On the basis of currently known distributions, overall our results strongly support the importance of a dual conservation strategy in Britain, in which protected areas are maintained with particular reference to those biodiversity features (such as many threatened plant species) that are highly dependent on them, and in which components of the wider landscape are also managed in such a way as to promote the abundance and distribution of such features with particular reference to those which are unlikely to persist in protected areas alone.  相似文献   

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