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1.
The impact of crop management and agricultural land use on the threat status of plants adapted to arable habitats was analysed using data from Red Lists of vascular plants assessed by national experts from 29 European countries. There was a positive relationship between national wheat yields and the numbers of rare, threatened or recently extinct arable plant species in each country. Variance in the relative proportions of species in different threat categories was significantly explained using a combination of fertilizer and herbicide use, with a greater percentage of the variance partitioned to fertilizers. Specialist species adapted to individual crops, such as flax, are among the most threatened. These species have declined across Europe in response to a reduction in the area grown for the crops on which they rely. The increased use of agro-chemicals, especially in central and northwestern Europe, has selected against a larger group of species adapted to habitats with intermediate fertility. There is an urgent need to implement successful conservation strategies to arrest the decline of this functionally distinct and increasingly threatened component of the European flora.  相似文献   

2.
A joint analysis considering the world-wide distribution and threat status of Central European vascular plants was carried out to derive conservation priorities for threatened species. A list of 417 taxa is presented, which are threatened throughout Central Europe and/or show a predominantly Central European distribution. As a first step, all plants mentioned in Central European national Red Lists were included in a synoptic table, resulting in a total of 3255 taxa threatened or rare in at least one country. To select species with a high conservation priority, two parameters were estimated: threat status for Central Europe and a new category termed responsibility for the conservation of a species. As criteria for this second parameter, we used the proportion of Central Europe on the world range of a species, the position of Central Europe within this range, and its world-wide threat status. A simple category system including four responsibility categories is proposed. For all species selected, threat status and a responsibility assessment for the whole of Central Europe is given, as well as position and proportion of Central Europe on their world range. By comparison of threat status and responsibility, this list provides a background for assessing national conservation priorities as well as for making decisions about inclusion in international conventions on species conservation. This was shown by a comparison of the species selected using this approach with those included in the two most important European instruments for species conservation – the Berne Convention and the Habitats Directive.  相似文献   

3.
The knowledge about the conservation status of species is an important data for conservation biology. Therefore, threatened species lists are a powerful tool for conservation planning and prioritization. Our objective is to compare the global, the national and state red lists of amphibians in Brazil. Threatened species were categorized according to their listing in one or several of these lists. We analyzed for true inconsistencies across lists in order to evaluate practical consequences of such incongruences on amphibian conservation in Brazil. We recorded a total of 61 threatened amphibian species in Brazil (across all red lists). Only one species, Phrynomedusa fimbriata, was listed as Extinct (both in IUCN, Brazil and S?o Paulo lists). A total of eleven endemic species are listed as threatened by the global red list, but do not appear in Brazil’s national red list, which represent an inconsistence among these lists. Besides that, the threat category of Thoropa lutzi and Thoropa petropolitana, two endemic species, differ among both lists, which also represents a problem between both lists. These mismatches may be due to several reasons such as different interpretation of the criteria; different methodologies used; different data availability on species; differences in the dates of assessments processes; the assessors’ attitudes to uncertainty; outdated red lists. Harmonization among red lists permits a better picture of threatened amphibian diversity across scales and to develop global, national and state plans to complement conservation actions in order to maximize the chance of success of these initiatives.  相似文献   

4.
Namibia supports a highly diverse avifauna of 644 species, including over 90 species endemic to the southern African subregion and 13 species endemic to the country. Patterns of species diversity in relation to protected areas and habitat types were analysed using data from the Southern African Bird Atlas Project. A modified Shannon index appropriate for atlas data was used to derive an index of diversity for all species, wetland, terrestrial, threatened, and regional endemic species. Species richness for Namibian endemics was mapped. Overall species diversity is highest in the northeast of Namibia where wetland and riparian habitats coincide. Both wetland and terrestrial species show highest diversity in this area. The greatest diversity of southern African endemics falls within the Savanna-Karoo systems. Several key areas are identified for red data species, including the Caprivi Strip, Kunene and Orange Rivers, coastal wetlands and ephemeral river mouths and pans. This highlights the pressures operating on wetland and riparian habitats in arid environments. Concentrations of Namibian endemics are found in the northwestern (Kaoko) escarpment of the country. Although much of the area of high diversity of wetland, terrestrial and red data species falls within protected areas, national and regional endemics are poorly represented within national parks.  相似文献   

5.
基于实地考察、文献资料和标本数据,借助GIS技术构建桂西黔南生物多样性保护优先区的39种国家重点保护植物空间地理分布格局,结合30m空间分辨率遥感影像解译的植被与地表覆盖数据,研究该优先区内的国家重点保护物种的生境与植被类型的关系及保护现状,并就优先区国家重点保护植物的地理分布格局分析优先区以外的保护空缺。此外,对优先区近二十年来的植被与地表覆盖特征的时空变化进行分析研究,结果优先区的人居用地、湿地(包括水库)面积分别增加67.75km2和371.11km2,森林面积相对稳定,灌丛和草丛面积分别减少230.69km2和174.70km2。该地区的国家重点保护植物正面临着生境退化和丧失的威胁。在此基础上对国家重点保护植物今后的保护及监测提出了对策和建议,为生物多样性研究、保护空缺分析、植被时空变化研究以及动态监测等方面的工作提供借鉴。  相似文献   

6.
Natural wetland ecosystems continue to suffer widespread destruction and degradation. Many recent studies argue that artificial or restored wetlands compensate for wetland loss and are valuable for waterbird conservation. However, detailed comparisons of the value of natural, artificial and restored wetlands are lacking. Our aim was to assess if the restoration or creation of wetlands can fully compensate for the loss of natural wetlands for waterbirds. We compared the waterbird communities in a set of 20 natural, restored and artificial wetlands, all of which are considered important for waterbirds and are located within the same protected area (Doñana Natural Space, south‐west Spain). We used different measures of diversity, including phylogenetic relatedness, and the proportion of threatened species at national, European and international levels. We found that artificial wetlands have consistently lower value than restored and natural wetlands, with little difference between the latter two. Natural wetlands are essential for conserving diversity across the tree of life and for threatened species, but restored wetlands can be of similar value and can assure maintenance of key ecological processes. Thus, when economic costs per unit area are similar, resources for wetland conservation are better invested in restoration projects than in wetland creation, and caution is required when suggesting that artificial wetlands compensate for the loss of natural wetlands.  相似文献   

7.
Orchidaceae is a mega diverse family accounting for 10% of the world’s flowering plants. Due to factors such as small dispersed populations, specific symbiosis with fungi and with pollinators and their desirability for collecting, many orchids are threatened with extinction. Tourism and recreation is increasingly recognised as a global threat for plants, but is it an issue for orchids? When data on orchids from the International Union for Nature Conservation (IUCN) Red List was reviewed, we found that 149 (40%) of the 442 orchid species with threat data were at risk from tourism and recreation. This included: 98 (22%) species threatened by residential and commercial development for tourism and recreation, 75 (17%) by intentional collecting within protected areas, and 90 (20%) by human intrusions and disturbance from recreational activities. The three threats often co-occurred and hence can be treated as a threat syndrome. The proportion of species threatened varied among locations with 80% of the 65 species in East Asia, 32% of 68 species in South and Southeast Asia and 94% of 16 orchid species in Europe threatened by tourism and recreation. Terrestrial orchids and those growing in forests were more likely to be at risk from these threats. With so many species at risk, increased awareness and recognition of these threats combined with improved management to reduce impacts is needed. Gaps and inconsistencies in the IUCN Red List must also be addressed to obtain a better understanding of the extent of this, and other threats to plants.  相似文献   

8.
在对雅鲁藏布江下游地区兰科(Orchidaceae)植物资源进行调查的基础上,结合资料收集和标本查阅,利用多个评价指标定量计算各濒危植物的优先保护值,确定该区域珍稀濒危兰科植物的濒危等级和优先保护序列。结果表明:对雅鲁藏布江下游地区的60属156种濒危兰科植物濒危等级进行评价,其中处于极危(CR)状态的有15种,处于濒危(EN)状态的有46种,处于易危(VU)状态的有78种,处于近危(NT)状态的有17种;优先保护范围值为0.853 9~0.416 8,其中被划分为Ⅰ级保护植物有45种,Ⅱ级保护植物有72种,Ⅲ级保护植物有39种。该研究结果与各种保护植物名录的濒危程度和优先保护级别存在较大差异,大部分兰科植物在该区受威胁程度加强,与这些兰科植物在雅鲁藏布江下游地区现实生存状态基本保持一致,对该区域兰科植物的保护迫在眉睫,应引起足够重视。  相似文献   

9.
城镇化进程中的建成区扩张会对区域自然生态安全格局造成胁迫效应.本文选取北京通州、河北正定、天津塘沽及福建厦门4个内陆和沿海城市为研究区,通过景观生态学原理构建区域景观胁迫分析指标,对比分析4个城市快速扩张区域在快速城镇化过程中表现出的景观格局特征,研究不同区域及城镇化背景下人工景观对耕地、绿/林地、水体和未利用地等自然景观生态安全格局的胁迫作用差异.结果表明: 2015年,通州、正定、塘沽和厦门4个城市扩张区的景观侵蚀指数分别为1.039、0.996、1.239和0.945,自然景观都表现出显著的被侵蚀程度;但不同城市区域的各类自然景观类型受威胁的程度不同,通州、正定和塘沽以未利用地和水域为主,厦门则以耕地和水域为主,4个城市水域威胁指数均超过0.743;内陆城市的水域和未利用地景观分离度指数均大于沿海城市,在空间上表现为沿海城市水体分布较内陆城市更聚集;相对于其他自然景观,未利用地和水域是受人工景观胁迫最大的两种自然景观.  相似文献   

10.
Using the assessments of conservation status of flora and fauna, we discuss declining species in semi-natural field margins and stress the importance of these vanishing habitats. Seventy field margins in the diverse farmland of SW Poland were investigated with regard to their vascular plants, bryophytes and breeding birds. We checked the occurrence of threatened and conservation concern species, i.e. those listed in local, national or European threatened species lists, and birds with an unfavorable conservation status in Europe. Of a total of 673 species, 18 classified as threatened were recorded: 12 vascular plants (2.2 % of the total number of species), five bryophytes (5.6 %), and one bird species (2.0 %). Threatened plants occurred in 18.6 % of study plots, bryophytes in 20.0 % and birds in 12.9 %. Eleven bird species, noted in 95.7 % of study plots, had an unfavorable conservation status in Europe. Increasing volumes of trees and shrubs significantly increased the overall richness in each taxa. In percentage terms the occurrence of focal species in all three taxa tended to be higher in shrubby than in herbaceous and tree-lined margins. Our data demonstrate that field margins in Central European arable farmland regularly support rare and threatened species, and therefore deserve greater conservation efforts. Red lists along with alternative listing approaches can be employed to evaluate the biodiversity of fine-scale habitats, but their applicability depends on the taxonomic group and geographical scale of the lists, reflecting different conservation priorities.  相似文献   

11.
Do we need land‐cover data to model species distributions in Europe?   总被引:8,自引:0,他引:8  
Aim To assess the influence of land cover and climate on species distributions across Europe. To quantify the importance of land cover to describe and predict species distributions after using climate as the main driver. Location The study area is Europe. Methods (1) A multivariate analysis was applied to describe land‐cover distribution across Europe and assess if the land cover is determined by climate at large spatial scales. (2) To evaluate the importance of land cover to predict species distributions, we implemented a spatially explicit iterative procedure to predict species distributions of plants (2603 species), mammals (186 species), breeding birds (440 species), amphibian and reptiles (143 species). First, we ran bioclimatic models using stepwise generalized additive models using bioclimatic variables. Secondly, we carried out a regression of land cover (LC) variables against residuals from the bioclimatic models to select the most relevant LC variables. Finally, we produced mixed models including climatic variables and those LC variables selected as decreasing the residual of bioclimatic models. Then we compared the explanatory and predictive power of the pure bioclimatic against the mixed model. Results (1) At the European coarse resolution, land cover is mainly driven by climate. Two bioclimatic axes representing a gradient of temperature and a gradient of precipitation explained most variation of land‐cover distribution. (2) The inclusion of land cover improved significantly the explanatory power of bioclimatic models and the most relevant variables across groups were those not explained or poorly explained by climate. However, the predictive power of bioclimatic model was not improved by the inclusion of LC variables in the iterative model selection process. Main conclusion Climate is the major driver of both species and land‐cover distributions over Europe. Yet, LC variables that are not explained or weakly associated with climate (inland water, sea or arable land) are interesting to describe particular mammal, bird and tree distributions. However, the addition of LC variables to pure bioclimatic models does not improve their predictive accuracy.  相似文献   

12.
Changes in land use/land cover are a major driver of biodiversity change in the Mediterranean region. Understanding how animal populations respond to these landscape changes often requires using landscape mosaics as the unit of investigation, but few previous studies have measured both response and explanatory variables at the land mosaic level. Here, we used a "whole-landscape" approach to assess the influence of regional variation in the land cover composition of 81 farmland mosaics (mean area of 2900 ha) on the population density of a threatened bird, the little bustard (Tetrax tetrax), in southern Portugal. Results showed that ca. 50% of the regional variability in the density of little bustards could be explained by three variables summarising the land cover composition and diversity in the studied mosaics. Little bustard breeding males attained higher population density in land mosaics with a low land cover diversity, with less forests, and dominated by grasslands. Land mosaic composition gradients showed that agricultural intensification was not reflected in a loss of land cover diversity, as in many other regions of Europe. On the contrary, it led to the introduction of new land cover types in homogenous farmland, which increased land cover diversity but reduced overall landscape suitability for the species. Based on these results, the impact of recent land cover changes in Europe on the little bustard populations is evaluated.  相似文献   

13.
Assemblages of macroalgal species present in the upper reaches of estuaries were compared using published species lists for the North Atlantic, covering a north-south gradient in Europe from Iceland to northern Spain, and in North America between the St. Lawrence and Virginia. Patterns were sought using cluster analysis and ordination. Three groupings of estuaries were noted: Icelandic, mainland European and American. There was a slight trend of increase in the ratio of red to brown algae with decreasing latitude in Europe, though not as marked as for open coastal algae. This might be associated with the effect of temperature on salinity tolerance. Despite this biogeographic trend, some of the commonest species appear to be widely spread through estuaries, possibly including southern Atlantic and Pacific locations. Confirmation of the trends suggested requires further data from southern European estuaries.  相似文献   

14.
Vulnerability of 100 European butterfly species to climate change was assessed using 13 different criteria and data on species distributions, climate, land cover and topography from 1,608 grid squares 30′ × 60′ in size, and species characteristics increasing the susceptibility to climate change. Four bioclimatic model-based criteria were developed for each species by comparing the present-day distribution and climatic suitability of the occupied grid cells with projected distribution and suitability in the future using the HadCM3-A2 climate scenario for 2051–2080. The proportions of disadvantageous land cover types (bare areas, water, snow and ice, artificial surfaces) and cultivated and managed land in the occupied grid squares and their surroundings were measured to indicate the amount of unfavourable land cover and dispersal barriers for butterflies, and topographical heterogeneity to indicate the availability of potential climatic refugia. Vulnerability was also assessed based on species dispersal ability, geographical localization and habitat specialization. Northern European species appeared to be amongst the most vulnerable European butterflies. However, there is much species-to-species variation, and species appear to be threatened due to different combinations of critical characteristics. Inclusion of additional criteria, such as life-history species characteristics, topography and land cover to complement the bioclimatic model-based species vulnerability measures can significantly deepen the assessments of species susceptibility to climate change.  相似文献   

15.
Global Red List data on mammals, birds and plants for over 100non-island nations are used to identify the impact of area, endemism, humanpopulation, and many other social variables (urbanized population,human-dominated land, national wealth, % land protected) on proportions ofthreatened species among nations. Human population size and, especially,proportion of endemic species emerge as the strongest correlates of proportionof threatened species in nations. Area tends to increase both human populationand proportion of endemics and thus increases the proportion of threatenedspecies. Increasing wealth is associated with increased relative threat inmammals and plants. Proportion of land protected is significantly associatedwith decreased relative threat in mammals and birds.  相似文献   

16.
The aims of this study were (1) to examine the geographic distribution of red-listed species of agricultural environments and identify their national threat spots (areas with high diversity of threatened species) in Finland and (2) to determine the main environmental variables related to the richness and occurrence patterns of red-listed species. Atlas data of 21 plant, 17 butterfly and 11 bird species recorded using 10 km grid squares were employed in the study. Generalized additive models (GAMs) were constructed separately for species richness and occurrence of individual species of the three species groups using climate and land cover predictor variables. The predictive accuracy of models, as measured using correlation between the observed and predicted values and AUC statistics, was generally good. Temperature-related variables were the most important determinants of species richness and occurrence of all three taxa. In addition, land cover variables had a strong effect on the distribution of species. Plants and butterflies were positively related to the cover of grasslands and birds to small-scale agricultural mosaic as well as to arable land. Spatial coincidence of threat spots of plants, butterflies and birds was limited, which emphasizes the importance of considering the potentially contrasting environmental requirements of different taxa in conservation planning. Further, it is obvious that the maintenance of various non-crop habitats and heterogeneous agricultural landscapes has an essential role in the preservation of red-listed species of boreal rural environments.  相似文献   

17.
Protected areas in the European Union under the Natura 2000 reserve system cover about 17 percent of the total land area. Systematic evaluations of the effectiveness of the current reserve system have been scarce and restricted to regional assessments. One reason for that may be the poor availability of comprehensive fine scale biodiversity data for the highly fragmented and densely human-populated European continent. We apply recently developed modeling tools for systematic conservation planning to conduct a detailed gap analysis using coarse scale species occurrence data. The employed mathematical model uses mixed integer programming to determine the cost-minimizing distribution of habitat locations subject to biophysical, economic, and policy restrictions. We include fine scale wetland habitat data as well as species-specific proxies for population density and viable population threshold. First, we evaluate the performance of the current Natura 2000 system in covering endangered wetland vertebrate species. Results show that five area-demanding vertebrates are not covered by the current reserve system. Second, we identify potentials for expanding the network to move toward complete coverage for the considered species mostly in countries of North-Eastern Europe. About 3 million hectares of additional reserve area at a cost of 107 million Euro per year would be required to achieve coverage of all considered species. Third, we present spatially explicit priority regions for a cost-effective expansion of the current reserve network.  相似文献   

18.
The European flora is of global significance but many species are facing an ever increasing range of threats, especially the growing impacts of climate change. While various estimates have been made for the number of threatened plant species in Europe, an up-to-date European plant Red List does not presently exist. Target 8 of the Global Strategy for Plant Conservation (GSPC) calls for 60% of threatened plant species to be conserved in ex situ collections by 2010. In the absence of a European plant Red List, it is difficult to monitor progress at the regional level towards this target. To address this gap Botanic Gardens Conservation International (BGCI) has developed a consolidated list of European threatened species as a step towards a formal Red List. The database consists of national Red List data from 28 European countries and includes records for over 11,000 taxa. National Red List data were supplemented by information on the critically endangered plants of Europe provided by the Museum National d’Histoire Naturelle/European Topic Centre on Biological Diversity and the Conservatoire Botanique National de Brest. A list of regionally threatened species was extracted from the database and screened against BGCI’s database of plants in cultivation in botanic gardens (PlantSearch) and ENSCONET’s (European Native Seed Conservation Network) database of plants conserved in European seed banks. This analysis revealed that 42% of European threatened species are currently included in ex situ conservation programmes in Europe.  相似文献   

19.
Maps of continental‐scale land cover are utilized by a range of diverse users but whilst a range of products exist that describe present and recent land cover in Europe, there are currently no datasets that describe past variations over long time‐scales. User groups with an interest in past land cover include the climate modelling community, socio‐ecological historians and earth system scientists. Europe is one of the continents with the longest histories of land conversion from forest to farmland, thus understanding land cover change in this area is globally significant. This study applies the pseudobiomization method (PBM) to 982 pollen records from across Europe, taken from the European Pollen Database (EPD) to produce a first synthesis of pan‐European land cover change for the period 9000 bp to present, in contiguous 200 year time intervals. The PBM transforms pollen proportions from each site to one of eight land cover classes (LCCs) that are directly comparable to the CORINE land cover classification. The proportion of LCCs represented in each time window provides a spatially aggregated record of land cover change for temperate and northern Europe, and for a series of case study regions (western France, the western Alps, and the Czech Republic and Slovakia). At the European scale, the impact of Neolithic food producing economies appear to be detectable from 6000 bp through reduction in broad‐leaf forests resulting from human land use activities such as forest clearance. Total forest cover at a pan‐European scale moved outside the range of previous background variability from 4000 bp onwards. From 2200 bp land cover change intensified, and the broad pattern of land cover for preindustrial Europe was established by 1000 bp . Recognizing the timing of anthropogenic land cover change in Europe will further the understanding of land cover‐climate interactions, and the origins of the modern cultural landscape.  相似文献   

20.
Measuring threat and selecting ??flagship?? species for conservation planning should ideally rely on ??dynamic?? criteria (i.e.: decreasing range and population sizes) which may not be available for most taxa and geographic regions. We address the question of what features of the organisms or of their geographic distributions lie behind selections of potentially threatened species when there is insufficient information on temporal trends. Focusing on Iberian butterflies, we evaluate the support for past and present lists of target species from the most easily quantifiable features of the species?? ranges and conspicuousness (size and visual apparency). Among the features tested, geographic rarity has the highest weight in all the species lists. However, the explanation is rather modest statistically, especially when the species selection is of a supra-regional nature (in this case European). Among the rarest species, those with geographic ranges concentrated in the study area (a) are comparatively few and (b) on average, have less restricted ranges than those whose geographic rarity results from their marginal occurrence in the study area. Finally, the total geographic coverage of the EU-threatened butterflies is relatively large in Iberia. As a consequence species-oriented conservation planning in this region may be rather unrealistic if only geographic rarity is emphasized, or if the levels of threat determined at the supra-regional (European) level are directly translated to the regional legislations. Thus we support the regionally hierarchical approach to conservation proposed by former authors.  相似文献   

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