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1.
In a perfect world, systematic conservation planning would use complete information on the distribution of biodiversity. However, information on most species is grossly incomplete. Two main types of distribution data are frequently used in conservation planning: observed and predicted distribution data. A fundamental question that planners face is - which kind of data is better under what circumstances? We used simulation procedures to analyse the effects of using different types of distribution data on the performance of reserve selection algorithms in scenarios using different reserve selection problems, amounts of species distribution known, conservation targets and costs. To compare these scenarios we used occurrence data from 25 amphibian and 41 reptile species of the Iberian Peninsula and assumed the available data represented the whole truth. We then sampled fractions of these data and either used them as they were, or converted them to modelled predicted distributions. This enabled us to build three other types of species distribution data sets commonly used in conservation planning: “predicted”, “transformed predicted” and “mixed”. Our results suggest that reserve selection performance is sensitive to the type of species distribution data used and that the most cost-efficient decision depends most on the reserve selection problem and on how much we have of the species distribution data. Choosing the most appropriate type of distribution data should start by evaluating the scenario circumstances. While there is no one best approach for every scenario, we discovered that using a mixed approach usually provides an acceptable compromise between species representation and cost.  相似文献   

2.
Important Plant Areas in Italy: From data to mapping   总被引:1,自引:0,他引:1  
Three hundred and twelve Important Plant Areas (IPAs) have been identified in Italy using a grid-based ranking system to pinpoint areas of high richness and conservation value, alongside the more frequently used expert-based selection of sites. Important Plant Areas are defined as the most important places in the world for wild plant diversity and need to be identified according to common criteria. The main methodological challenges are the lack of recent, easily accessible data for species and habitats and the definition of practical boundaries. The Global Strategy for Plant Conservation (GSPC–CBD) aims to protect 50% of the most important areas for plant diversity and to conserve in situ 60% of the threatened species by 2010. To measure the extent to which the GSPC targets were fulfilled, we assessed the level of protection afforded to the IPAs and species.We identified 351 top ranking cells, which yielded a total of 312 IPAs, covering approximately 15% of Italy. More than 80% of the IPAs currently have some form of legal protection and over 60% of the selected species are included in the existing protected areas. The method we are proposing may be used where no systematic data collection program exists. The transition from grids to polygons is an “expert-based passage” that exploits different sources of information, such as species point locality data, vegetation maps and expert-based indications. IPAs fit into a wider conservation context and may be applied to the design of ecological networks, the zonation of existing protected areas and the definition of key biodiversity areas.  相似文献   

3.
Climate change has created the need for new strategies in conservation planning that account for the dynamics of factors threatening endangered species.Here we assessed climate change threat to the European otter, a flagship species for freshwater ecosystems, considering how current conservation areas will perform in preserving the species in a climatically changed future. We used an ensemble forecasting approach considering six modelling techniques applied to eleven subsets of otter occurrences across Europe. We performed a pseudo-independent and an internal evaluation of predictions. Future projections of species distribution were made considering the A2 and B2 scenarios for 2080 across three climate models: CCCMA-CGCM2, CSIRO-MK2 and HCCPR HADCM3. The current and the predicted otter distributions were used to identify priority areas for the conservation of the species, and overlapped to existing network of protected areas.Our projections show that climate change may profoundly reshuffle the otter’s potential distribution in Europe, with important differences between the two scenarios we considered. Overall, the priority areas for conservation of the otter in Europe appear to be unevenly covered by the existing network of protected areas, with the current conservation efforts being insufficient in most cases. For a better conservation, the existing protected areas should be integrated within a more general conservation and management strategy incorporating climate change projections. Due to the important role that the otter plays for freshwater habitats, our study further highlights the potential sensitivity of freshwater habitats in Europe to climate change.  相似文献   

4.
To improve effectiveness of protected areas, selection of priority areas should include consideration of three main components, namely special conservation elements, focal species and representation. We present a three-track approach related to these components for vertebrate conservation planning in Castilla-La Mancha, central Spain. As special conservation elements, we identified Priority Areas for Conservation of species using five criteria: species richness, geographic rarity, species vulnerability, a Combined Index of these three criteria, and a Standardised Biodiversity Index (SBI) that integrate the three criteria and four studied taxa. The Natura 2000 Network was used to include conservation areas for focal species. We evaluated the representation of every landscape type in the existing conservation areas. To delineate the spatial configuration for vertebrate conservation, we combined the identified Priority Areas for Conservation, existing conservation areas and connectivity areas by cost–distance analysis. The Combined Index was the most efficient criterion analyzed to identify Priority Areas for Conservation. The Natura 2000 Network showed a high percentage of coincidence with identified Priority Areas for Conservation, whereas the natural protected areas network had a low percentage of coincidence. Six agricultural landscapes were inadequately represented in the current conservation network. According to our multi-track approach, ∼29% of study area was required to capture 100% of vertebrate species and all landscape types. Our results show that the existing conservation areas are insufficient to guarantee the conservation of biodiversity in the study region. Additional areas with outstanding features of diversity, connectivity areas, and establishment of targets for off-reserve conservation are of fundamental importance for strengthening biodiversity conservation.  相似文献   

5.
Amphibians are an important and imperiled component of biodiversity. In this study we analyze the efficacy of Italian reserve network for protecting multiple amphibian species in a climate change scenario, considering both nationally designated areas and Natura 2000 sites. Our approach is based on ensemble niche modeling estimate of potential range shift under two carbon emission scenarios (A1FI and B1) and two dispersal assumptions. The predicted distributions were used to perform gap and irreplaceability analyses. Our findings show that the current Italian reserve network incompletely represents current amphibian diversity and its geographic pattern. The combination of the nationally designated protected areas and the Natura 2000 sites improves current representation of amphibians, but conservation targets based on geographic range extent are achieved for only 40% of species. Under the future scenarios, Natura 2000 sites become a crucial component of the protected areas system. Nonetheless, we predict that climate change decreases for many species the amount of suitable range falling into reserves, regardless of our assumptions about dispersal. We identify some currently unprotected areas that have high irreplaceability scores for species conservation and that maintain their importance under all the future scenarios we considered. We recommend designation of new reserves in these areas to help guarantee long-term amphibian conservation.  相似文献   

6.
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   

7.
In many cases, the designation of Protected Areas (PAs) is not based on biological information, particularly in tropical regions where such information is generally lacking. Thus it is unclear whether tropical PAs are well-placed for conserving biodiversity currently, or under future climate change. We used reserve-design software (‘Zonation’) to investigate current and future conservation value of PAs of Thailand (N = 187 PAs, covering ∼20% of Thailand) in relation to forest-cover and butterfly diversity. Currently, PAs are about 2 °C cooler than non-PAs because PAs tend to occur at higher elevation (66% of land above 1000 m is protected compared with only 6% below 250 m). Temperature is predicted to increase in Thailand in future, but PAs are predicted to remain ∼2 °C cooler than non-PAs in future. We obtained modelled distribution data for 161 butterfly species (∼12% of national butterfly fauna), and used Zonation to rank areas (∼1 km2 grid resolution) based on species richness, complementarity, and forest cover. The conservation value of PAs was approximately twice that of non-PA areas, although many highly-ranked areas are not currently protected. The species richness of PAs was projected to decline by ∼30% in future, but the relative conservation rankings of individual PAs were projected to change very little. The preponderance of PAs in montane regions makes them well-placed to support forest species shifting from areas at lower elevation that become climatically unsuitable in future. By contrast, the conservation value of low-elevation PAs may decline in future if climate conditions become unsuitable for species.  相似文献   

8.
The growing concern about the profound influence of human activities on marine ecosystems has been the driving force behind the creation of marine reserves in the last few decades. With almost 4200 km of coastline, Chile has not been the exception to this trend. A set of conservation priority sites has recently been proposed by the Chilean government to expand the current marine reserve network. In this study, we used the most comprehensive information currently available on the distribution of 2513 marine species in Chile to assess the efficiency of the existing system of marine protected areas (MPA) and the conservation priority sites identified by the government. Additionally, we evaluated the vulnerability of the reserve network selected with respect to threatening human activities. Our results show that both the existing protected areas and the proposed priority sites are relatively effective at protecting Chilean marine biodiversity. However, the majority of the species that are not represented within the existing or projected MPA network have very restricted distributions and are, therefore, of high conservation concern. To cover all species requires a network of 35 MPAs (46% of the total number of planning units). Many of the sites identified as irreplaceable present conflict with one or more human activities, particularly in the central region of the country. This study emphasizes the need for a systematic conservation planning approach to maximize the representation of species and prioritize those areas where conflicts between marine biodiversity conservation and human activities may occur.  相似文献   

9.
An approach to an overall management planning for the conservation of endangered species within protected natural areas is presented, based mainly on the development of methods for the diagnosis of the conservation status and the identification of critical life cycle stages (phenophases) of target species. This model includes other aspects inherent in the overall planning of a protected area so as to match its technical, human and economic resources in terms of research and conservation. We provide examples of some island endemics that are included in the “Recovery Plans for the Endangered Plants in the Canary Islands National Parks”. The use of demography and genetics is particularly emphasised. We propose reintroductions as one of the most important tools for the management and conservation of endangered plants and the use of “system dynamics” tools as an alternative to traditional population matrix analysis. We provide examples of the application of system dynamics to population dynamics studies and to the design of management actions.  相似文献   

10.
How can conservation planners optimally and effectively allocate limited resources between imminently threatened and presently secure areas? Such choices must be made at multiple spatial scales involving a variety of conservation targets. Allocation strategies range from a “fire-fighting” approach, which gives priority to heavily developed areas at high risk of further habitat loss, to a “pre-emptive” approach giving priority to intact habitat tracts before they become threatened. We determined optimal dynamic reserve selection strategies when selections are made in imminently threatened and presently secure areas that will become threatened at uncertain times in the future. The objective was to maximize the expected number of endemic species conserved, predicted with species-area curves. The model was solved for three forms of species-area curve proposed in theoretical studies of habitat loss. Alternative scenarios were considered on the relationship between land prices and development risk. For the most commonly proposed form of the species-area relationship, the fire-fighting approach is optimal even if land prices rise substantially when presently secure areas become threatened. This reflects the assumption that species decline accelerates only after a large proportion of original habitat has been lost. The possibility of large species losses at lower levels of habitat loss justifies at least some pre-emptive conservation, even if land prices are not correlated with threat. If species decline is proportional with habitat loss, the optimal conservation strategy depends strongly on land price dynamics.  相似文献   

11.
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   

12.
We tested the prediction that climate-driven changes might alter bird species composition in reserves of the Cerrado region of Brazil. First, we modelled the current distributions and the potential future projections of 38 endemic or rare bird species. We used eight modelling techniques within the BIOMOD computational framework in an ensemble-forecasting approach to reach a consensus scenario. Then we compared current and future (2046-2060) distributions under different scenarios (reserve size and bird dispersal) with the current Brazilian reserve system to assess the adequacy of protection (representation) of each species and detect gaps in their protection. Finally, to identify areas with high probability of occurrence of several species, we calculated cumulative climatic suitability of all 38 species for both current and future scenarios. None of the 38 species is covered under any current or future scenarios, revealing that the current reserve system is highly inefficient in conserving the analyzed bird species. The implementation of new reserves to cover species in current and future climate scenarios is recommended in areas in the south-eastern part of the Cerrado region and in the mountains of east Brazil. Due to the already high land use of the southeast region of the Cerrado, the application of non-traditional conservation measures should be evaluated.  相似文献   

13.
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   

14.
Areas of high conservation value were identified in the Western Ghats using a systematic conservation planning approach. Surrogates were chosen and assessed for effectiveness on the basis of spatial congruence using Pearson’s correlations and Mantel’s tests. The surrogates were, threatened and endemic plant and vertebrate species, unfragmented forest areas, dry forests, sub-regionally rare vegetation types, and a remotely sensed surrogate for unique evergreen ecosystems. At the scale of this analysis, amphibian richness was most highly correlated with overall threatened and endemic species richness, whereas mammals, especially wide-ranging species, were better at capturing overall animal and habitat diversity. There was a significant relationship between a remote sensing based habitat surrogate and endemic tree diversity and composition. None of the taxa or habitats served as a complete surrogate for the others. Sites were prioritised on the basis of their irreplaceability value using all five surrogates. Two alternative reserve networks are presented, one with minimal representation of surrogates, and the second with 3 occurrences of each species and 25% of each habitat type. These networks cover 8% and 29% of the region respectively. Seventy percent of the completely irreplaceable sites are outside the current protected area network. While the existing protected area network meets the minimal representation target for 88% of the species chosen in this study and all of the habitat surrogates, it is not representative with regard to amphibians, endemic tree species and small mammals. Much of the prioritised unprotected area is under reserve forests and can thus be incorporated into a wider network of conservation areas.  相似文献   

15.
The transformation and degradation of tropical forest is thought to be the primary driving force in the loss of biodiversity worldwide. Developing countries are trying to counter act this massive lost of biodiversity by implementing national parks and biological reserves. Costa Rica is no exception to this rule. National development strategies in Costa Rica, since the early 1970s, have involved the creation of several National Parks and Biological Reserves. This has led to monitoring the integrity of and interactions between these protected areas. Key questions include: “Are these areas' boundaries respected?”; “Do they create a functioning network?”; and “Are they effective conservation tools?”. This paper quantifies deforestation and secondary growth trends within and around protected areas between 1960 and 1997. We find that inside of national parks and biological reserves, deforestation rates were negligible. For areas outside of National Parks and Biological reserves we report that for 1-km buffer zones around such protected areas, there is a net forest gain for the 1987/1997 time period. Thus, it appears that to this point the boundaries of protected areas are respected. However, in the 10-km buffer zones we find significant forest loss for all study periods. This suggests that increasing isolation of protected areas may prevent them from functioning as an effective network.  相似文献   

16.
The significance of reserves in maintaining forest bird species of conservation concern (N = 36) was studied by large-scale quantitative line transect bird censuses in Finland, which stretches 1100 km through the boreal zone from the hemiboreal to the subarctic. Altogether 12 245 km of line transect was carried out in 1981-2004 in reserves covering 28 910 km2. Bird census data in protected areas were combined into 100 km × 100 km squares. As a group the studied bird species were rather evenly distributed throughout the reserve network. The present reserve network is particularly significant for species having their highest densities in northern Finland, because large proportions of the populations of these species occurred in protected areas. However, over half of the studied species were concentrated in protected areas of southern and central Finland, and only small proportions of their populations were included in the present reserve network. In contrast to the whole species pool of conservation concern, the studied individual forest bird species were not distributed evenly throughout the whole reserve network. This suggests that for most individual species a regionally concentrated network is a preferred option, but for the whole species group the reserve network should clearly be regionally complementary and representative even in the boreal zone, where species have rather wide ranges. Thus, only some species and their habitats can be preserved in a spatially uneven reserve network in boreal forests.  相似文献   

17.
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   

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.
20.
Given the widely recognized need to better protect the oceans but limited resources to do so, methods for prioritizing potential protected area sites are important. This is particularly true for the open oceans, where few protected areas currently exist and data availability is limited. Here, we examine the relationship between the distributions of tuna and billfish species richness (an indicator of pelagic biodiversity), the human impact drivers of fishing pressure (quantified as cumulative removals) and sea surface temperature increase (quantified as the increase in large positive anomalies) in tropical to temperate oceans at the scale of a 5° × 5° grid. We investigate relationships using Generalised Additive Models and Regression Tree analysis, and identify the top 50 “hotspot” cells for species richness and each of the two impact drivers. We find that both impact drivers significantly overlap with high species richness, but relationships are complex, non-linear and ocean-basin specific. Higher fishing pressure is associated with higher species richness in the Indian and Pacific Oceans, and this overlap is particularly prominent in the central Pacific, and in the Indian Ocean around Sri Lanka. In the Pacific and Atlantic Oceans, species richness is generally higher in areas that have seen lower levels of change in sea surface temperature and only one cell, near Easter Island, is a hotspot for species richness and sea surface temperature increase. While species richness and impact drivers overlap in some areas, there are many areas with high species richness and limited apparent impact. This suggests that area-based conservation strategies that aim to protect areas of high pelagic biodiversity may be achievable with limited displacement of fishing effort.  相似文献   

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