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1.
Fir forests (Abies, Pinaceae) are dominant in temperate regions of North America; however, they have experienced high degradation rates that can threaten their long-term continuity. This study aimed to identify the priority areas for the conservation of the genus Abies in North America. First, we modeled the species distribution of the 17 native species through ecological niche modeling, considering 21 environmental variables. Then, we defined the priority areas through multi-criteria analysis, considering the species richness, geographic rareness, irreplaceability, habitat degradation, and risk extinction. We also built six scenarios, giving more priority to each criterion. Finally, we identified the proportion of the extent of the priority areas covered by protected areas. Elevation, precipitation seasonality, and winter precipitation influenced the distribution of most of the Abies species. When considering equal weights to each criterion, the priority areas summed up 6% of the total extent covered by the Abies species in North America. Most priority areas were located on the West Coast of the United States, the Eastern Sierra Madre, Southern Sierra Madre, Sierras of Chiapas and Central America, and the Trans-Mexican Volcanic Belt ecoregions. In these ecoregions, the Abies species are restricted to small areas facing high degradation levels. Only 16% of the area covered by the Abies species in North America is protected, mainly under restrictive schemes such as National Parks and Wilderness Areas. The priority areas identified could be the basis for establishing or enlarging protected areas. The preservation of the genus Abies could also maintain other ecological features and processes such as biodiversity, forest resources, and environmental services.  相似文献   

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Global climate and land-use changes are the most significant causes of the current habitat loss and biodiversity crisis. Although there is information measuring these global changes, we lack a full understanding of how they impact community assemblies and species interactions across ecosystems. Herein, we assessed the potential distribution of eight key woody plant species associated with the habitat of the endangered Lilac-crowned Amazon (Amazon finschi) under global changes scenarios (2050′s and 2070′s), to answer the following questions: (1) how do predicted climate and land-use changes impact these species’ individual distributions and co-distribution patterns?; and (2) how effective is the existing Protected Area network for safeguarding the parrot species, the plant species, and their biological interactions? Our projections were consistent identifying the species that are most vulnerable to climate change. The distribution ranges of most of the species tended to decrease under future climates. These effects were strongly exacerbated when incorporating land-use changes into models. Even within existing protected areas, >50 % of the species’ remaining distribution and sites with the highest plant richness were predicted to be lost in the future under these combined scenarios. Currently, both individual species ranges and sites of highest richness of plants, shelter a high proportion (ca. 40 %) of the Lilac-crowned Amazon distribution. However, this spatial congruence could be reduced in the future, potentially disrupting the ecological associations among these taxa. We provide novel evidence for decision-makers to enhance conservation efforts to attain the long-term protection of this endangered Mexican endemic parrot and its habitat.  相似文献   

3.
With only five protected areas dedicated to the conservation of biodiversity (two national parks, one strict nature reserve and two faunal reserves), Guinea has one of the smallest protected area networks in West Africa. As a result, two of the five ecoregions of the country and six of the 14 globally threatened large and medium-sized mammals occurring in Guinea are not found in the national protected area network. To identify areas with high biodiversity that could be included in the national protected area network, we used the Key Biodiversity Areas (KBA) methodology. We devised a scoring system to rank the identified KBAs according to their relative conservation significance. We identified a total of 16 KBAs throughout the country. Their proclamation as protected areas would result in the protection of all ecoregions and all but one of Guinea’s globally threatened large and medium-sized mammals. Twelve of the 16 KBAs have the legal status of classified forest, a status that should facilitate the change into formal biodiversity protected areas (IUCN category I–IV). Our analysis indicates that even if only the two areas with the highest conservation significance score, the Ziama and Diécké forests, become formal protected areas, this would provide protection to both the western Guinean lowland forests, one of the most threatened ecoregions in Africa, and to 11 of the 14 threatened large and medium-sized mammals occurring in Guinea.  相似文献   

4.
Biodiversity and biodiversity conservation in Yunnan, China   总被引:4,自引:3,他引:4  
Yunnan, an inland province at a low latitude and high elevation, lying between 21°09–29°15 N and 97°32–106°12 E in southwestern China, has a vast territory with diversified and unique nature resources. There are more than 18000 high plant species (51.6% of China's total) and 1836 vertebrate species (54.8% of China's total) living in Yunnan on a land area of 39.4 × 104km2, i.e., only 4.1% of China's total. Among 15000 seed plants found in Yunnan there are 151 rare and endangered plant species (42.6% of China's protected plants). Out of 335 China priority protected wild animals, Yunnan has 243 species, accounting for 72.5% of China's total, 15% of which are species endemic to Yunnan. However, Yunnan's biodiversity is faced with the menace of excessive exploitation of resources and changes in environmental conditions caused by the activities of an expanding human population. This paper discusses the background, the composition, and the structure of Yunnan's biodiversity. Its biodiversity fragility and the threatened situation are also discussed. Suggestions and recommendations on the strategy and actions of Yunnan biodiversity conservation and sustainable development are proposed.  相似文献   

5.
The rich biodiversity repository of the Niger Delta region of Nigeria is under severe threat from diverse sources such as deforestation, inadequate farming practices, invasive alien species, urbanization and oil and gas exploration and development activities. This biodiversity “hot spot” is the second most sensitive environment in Africa. The over 70 Protected Areas (PAs) here have lost substantial portions of their area which translates to loss of biodiversity. The need to select representative sites within each of the ecological zones of the region for effective and sustainable biodiversity conservation is, therefore, essential. Vital site criteria that have ecological, socio-economic and cultural dimensions were selected and assessed through a combination of relevant scientific information, indigenous traditional knowledge and participatory rural appraisal (PRA) to yield Key Biodiversity Areas (KBAs).They are significantly different from the site selection criteria and principles used in the UK and to a large extent adopt the critical factors that underscore biodiversity conservation in a largely primary production based economy such as in much of the developing world. The three sites selected for biodiversity conservation through this process yielded not only community buy-in but also participatory action and ownership, which are critical for the sustainability of the biodiversity conservation efforts. Shell Nigeria and World Wide Fund (WWF) representatives are already concluding plans to commence effective conservation projects in the selected sites. This approach is hereby advocated for consideration and adoption for the preservation of the remaining stock of the unique biodiversity in developing countries.  相似文献   

6.
Protected areas (that are usually designated) play an important role in the effort to halt on-going losses of biodiversity. However, areas outside of designated sites for protection can also hold important elements of biodiversity, and knowledge of their distribution is necessary to ensure effective conservation strategies. We collated and mapped vascular plant distribution data for species of conservation concern on the island of Ireland. For the first time in Ireland, we extracted 6078 distribution records of 176 species of conservation concern and mapped them at the tetrad (2 km × 2 km) scale. We examined the extent to which tetrads with records of species of conservation concern overlapped with designated areas (Natura 2000, Natural Heritage Areas, Areas of Special Scientific Interest). A conservative estimate suggests that many of these tetrads do not overlap with designated areas (in the range of 22–40% for available records). The coincidence of records of individual species with designated areas ranged from 0% to 100% (mean = 79%). The mapped distribution data for all vascular plant species offers guidance to where additional recording may be helpful in supporting conservation activities. The analysis of the distribution of species of conservation concern indicates the importance of both designated areas and the (non-designated) wider countryside for biodiversity conservation. In particular the presence of species of conservation concern in non-designated areas highlights the need for conservation measures outside of designated areas.  相似文献   

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IndiSeas (“Indicators for the Seas”) is a collaborative international working group that was established in 2005 to evaluate the status of exploited marine ecosystems using a suite of indicators in a comparative framework. An initial shortlist of seven ecological indicators was selected to quantify the effects of fishing on the broader ecosystem using several criteria (i.e., ecological meaning, sensitivity to fishing, data availability, management objectives and public awareness). The suite comprised: (i) the inverse coefficient of variation of total biomass of surveyed species, (ii) mean fish length in the surveyed community, (iii) mean maximum life span of surveyed fish species, (iv) proportion of predatory fish in the surveyed community, (v) proportion of under and moderately exploited stocks, (vi) total biomass of surveyed species, and (vii) mean trophic level of the landed catch. In line with the Nagoya Strategic Plan of the Convention on Biological Diversity (2011–2020), we extended this suite to emphasize the broader biodiversity and conservation risks in exploited marine ecosystems. We selected a subset of indicators from a list of empirically based candidate biodiversity indicators initially established based on ecological significance to complement the original IndiSeas indicators. The additional selected indicators were: (viii) mean intrinsic vulnerability index of the fish landed catch, (ix) proportion of non-declining exploited species in the surveyed community, (x) catch-based marine trophic index, and (xi) mean trophic level of the surveyed community. Despite the lack of data in some ecosystems, we also selected (xii) mean trophic level of the modelled community, and (xiii) proportion of discards in the fishery as extra indicators. These additional indicators were examined, along with the initial set of IndiSeas ecological indicators, to evaluate whether adding new biodiversity indicators provided useful additional information to refine our understanding of the status evaluation of 29 exploited marine ecosystems. We used state and trend analyses, and we performed correlation, redundancy and multivariate tests. Existing developments in ecosystem-based fisheries management have largely focused on exploited species. Our study, using mostly fisheries independent survey-based indicators, highlights that biodiversity and conservation-based indicators are complementary to ecological indicators of fishing pressure. Thus, they should be used to provide additional information to evaluate the overall impact of fishing on exploited marine ecosystems.  相似文献   

9.
Although Asian bamboo species constitute a non-timber forest product of major cultural and economic importance, no detailed regional assessment of their distribution patterns has previously been made. To assess the potential of the existing bamboo species distribution data for production of regional mapping tools for planning the conservation of forest-based biodiversity, data on bamboo distribution and forest cover were combined. Over 1000 bamboo species from 60 genera of woody bamboos were incorporated, allowing the mapping of individual species or groups of species and genera, along with potential species richness and biodiversity hotspots. Over 6.3 million km2 of Asian forest potentially contains bamboo, with highest densities indicated from northeastern India through Burma to southern China, and through Sumatra to Borneo. The highest figures for potential species richness (144 spp per square km) were recorded in forests of south China, including Hainan Island. Despite substantial inadequacies and inconsistencies in knowledge of the taxonomy and distribution of bamboo species, this approach may provide a valuable tool for planning in situ conservation of forest biodiversity.  相似文献   

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Statistical modelling of biological survey data in relation to remotely mapped environmental variables is a powerful technique for making more effective use of sparse data in regional conservation planning. Application of such modelling to planning in the northeast New South Wales (NSW) region of Australia represents one of the most extensive and longest running case studies of this approach anywhere in the world. Since the early 1980s, statistical modelling has been used to extrapolate distributions of over 2300 species of plants and animals, and a wide variety of higher-level communities and assemblages. These modelled distributions have played a pivotal role in a series of major land-use planning processes, culminating in extensive additions to the region's protected area system. This paper provides an overview of the analytical methodology used to model distributions of individual species in northeast NSW, including approaches to: (1) developing a basic integrated statistical and geographical information system (GIS) framework to facilitate automated fitting and extrapolation of species models; (2) extending this basic approach to incorporate consideration of spatial autocorrelation, land-cover mapping and expert knowledge; and (3) evaluating the performance of species modelling, both in terms of predictive accuracy and in terms of the effectiveness with which such models function as general surrogates for biodiversity.  相似文献   

12.
In conservation biogeography, the process of spatial conservation prioritization (SCP) aims to select areas that meet biodiversity targets at a minimum set coverage. Here, we propose a SCP scheme for the highly endemic and diverse anuran fauna of the Atlantic Forest (AF) and Cerrado (CER) South American hotspots under different climate change scenarios. Specifically, we make use of predicted anuran occurrences, built for baseline and future (2050 and 2070) time slices, and address biological and conservation metrics to identify potential priority regions for anuran conservation over time using the software MARXAN. Considering each time slice separately, the percentage area needed for total anuran representation varies at magnitudes of 9.8–10.66% for the AF and 6.4–8.8% for the CER. Pooling all time slices together in the selected conservation network, the identified spatial priorities account for 15.56% and 13.25% of the total AF and CER areas respectively. However, we identified opposing strategies for the anuran spatial conservation prioritization in the AF and CER over the different time periods; the increasing of priority cells across time considering the potential species redistribution under climate change in the AF, and the selection of fewer priority cells in the future than the identified for the baseline climate in the CER. The southeastern AF coast was identified as a priority area for amphibian conservation in this hotspot, as well as some other smaller areas in the northern and southern regions. Priority areas identified in the CER, although patchy distributed across the hotspot, are found in specific central-northern, western, and southeastern regions. The different conservation strategies identified in the present SCP emphasize the need for establishing different conservation efforts according to a sequential scheduling of priority areas that optimizes the long-term conservation goals.  相似文献   

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Regional conservation planning can often make more effective use of sparse biological data by linking these data to remotely mapped environmental variables through statistical modelling. While modelling distributions of individual species is the best known and most widely used approach to such modelling, there are many situations in which more information can be extracted from available data by supplementing, or replacing, species-level modelling with modelling of communities or assemblages. This paper provides an overview of approaches to community-level modelling employed in a series of major land-use planning processes in the northeast New South Wales region of Australia, and evaluates how well communities and assemblages derived using these techniques function as surrogates in regional conservation planning. We also outline three new directions that may enhance the effectiveness of community-level modelling by: (1) more closely integrating modelling with traditional ecological mapping (e.g. vegetation mapping); (2) more tightly linking numerical classification and spatial modelling through application of canonical classification techniques; and (3) enhancing the applicability of modelling to data-poor regions through employment of a new technique for modelling spatial pattern in compositional dissimilarity.  相似文献   

15.

Background

Humans threat the populations of tree species by overexploitation, deforestation, land use change, and climate change. We present a novel threat assessment at intraspecific level to support the conservation of genetic resources of 80 socioeconomically viable tree species in South America. In this assessment, we evaluate the threat status of Ecogeographic Range Segments (ERSs). ERSs are groups of populations of a specific species in a certain ecological zone of a particular grid cell of a species’ geographic occupancy.

Methods

We used species location records to determine the species distributions and species‐specific ERSs. We distinguished eight threat situations to assess the risk of extirpation of the ERSs of all 80 species. These threat situations were determined by large or little tree cover, low or high human pressure, and low or high climate change impact. Available layers of tree cover and threats were used to determine the levels of fragmentation and direct human pressure. Maxent niche modelling with two Global Circulation Models helped determining climate change impact by the 2050s.

Results

When all 80 species are considered, in total, 59% of the ERSs are threatened by little tree cover or high human pressure. When climate change is also considered, then 71‐73% of the ERSs are threatened. When an increased risk of extirpation of populations outside protected areas is considered, then 84–86% of the ERSs are threatened. Seven species warrant special attention because all their ERSs are threatened across their whole distribution in South America: Balfourondendron riedelianum, Cariniana legalis, Dalbergia nigra, Handroanthus pulcherrimus, Pachira quintana, Prosopis flexuosa, and Prosopis pallida.

Conclusions

Our results confirm the urgency to set up a regional action plan for the conservation of tree genetic resources in South America. With this threat assessment, we aim to support governments and organizations who are taking up this task.
  相似文献   

16.
黄路生  高军 《遗传学报》1999,26(4):315-323
分析了亚,欧,美,非21个野生,培育及地方猪种4个免疫遗传标记基因位点(E,F,G,L系统)和3人生化遗传标记基因位点(Cp,Am和Tf)的遗传多态性,认为E^aeg,F^a,Tf^c基因在亚洲猪种与欧美猪种间存在显著差异,是亚洲猪种3个重要的遗传标记基因,根据F^a基因频率在亚,欧,美,非猪种的变化规律分析了其基因流向特点,证明欧美猪的育种过程中利用了中国地方猪种的血缘,计算了所测猪种间的Nei  相似文献   

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Ecuador will experience a significant expansion of the oil industry in its Amazonian region, one of the most biodiverse areas of the world. In view of the changes that are about to come, we explore the conflicts between oil extraction interests and biodiversity protection and apply systematic conservation planning to identify priority areas that should be protected in different oil exploitation scenarios. First, we quantified the current extent of oil blocks and protected zones and their overlap with two biodiversity indicators: 25 ecosystems and 745 species (whose distributions were estimated via species distribution models). With the new scheme of oil exploitation, oil blocks cover 68% (68,196 km2) of the Ecuadorian Amazon; half of it occupied by new blocks open for bids in the southern Amazon. This region is especially vulnerable to biodiversity losses, because peaks of species diversity, 19 ecosystems, and a third of its protected zones coincide spatially with oil blocks. Under these circumstances, we used Marxan software to identify priority areas for conservation outside oil blocks, but their coverage was insufficient to completely represent biodiversity. Instead, priority areas that include southern oil blocks provide a higher representation of biodiversity indicators. Therefore, preserving the southern Amazon becomes essential to improve the protection of Amazonian biodiversity in Ecuador, and avoiding oil exploitation in these areas (33% of the extent of southern oil blocks) should be considered a conservation alternative. Also, it is highly recommended to improve current oil exploitation technology to reduce environmental impacts in the region, especially within five oil blocks that we identified as most valuable for the conservation of biodiversity. The application of these and other recommendations depends heavily on the Ecuadorian government, which needs to find a better balance between the use of the Amazon resources and biodiversity conservation.  相似文献   

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