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Protection of regional biodiversity requires that priority for protection of individual areas be based on both the contribution the area can make to representing overall biodiversity and the degree to which the area, in the absence of action, is vulnerable to loss of its biodiversity. Attempts to apply these criteria together largely have been ad hoc. A solution to this problem is presented for environmental surrogate data, based on environmental diversity (ED). ED uses a standard ecological continuum model to link environmental pattern to species-level biodiversity, so that a set of areas can be characterized by its relative expected biodiversity. This allows explicit incorporation of estimates of area-vulnerability, interpreted as the relative probability that any member species will not persist, into biodiversity assessments. The contribution of a given area to regional expected biodiversity is influenced not only by its own vulnerability value, but also by the vulnerability of other areas. Increasing the degree of protection of any area (reducing its vulnerability) will increase expected biodiversity: however, expected regional biodiversity sometimes may be maximized when limited resources for protection are directed to an area with lower vulnerability rather than to one with higher vulnerability.The allocation of land uses in a region need not be viewed as an all-or-nothing assignment of protection. The effect of a particular management regime on the biodiversity of a given area can be equated with some consequent degree of vulnerability; viewed positively, a management regime that offers some degree of biodiversity protection can make a measurable contribution to the protection of the biodiversity of a region.  相似文献   

3.
Habitat loss and fragmentation have highlighted the importance of monitoring remaining habitats. For megadiverse groups such as arthropods, of which many species are still being discovered, the use of higher taxonomic levels as substitutes for diversity may be a useful tool. The aim of this study was to evaluate the use of substitute taxonomic resolutions to assess the richness and composition of Laniatores harvestmen (Arachnida: Opiliones). The five resolutions selected were as follows: genus, family, subfamily, indicator taxa and intermediate resolution (combination of genus and species identification levels). In addition, we evaluated whether the diversity substitutes provide good estimates of latitudinal gradients. Nineteen Atlantic Forest sites located along a latitudinal gradient in northeastern Brazil were sampled. We recorded a total of 88 harvestmen species/morpho-species, distributed in 7 families, 15 subfamilies and 36 genera. Genus and intermediate resolution were excellent substitutes for harvestmen species richness. The efficiency differed according to the substitute resolution used. Four resolutions were adequate to replace the harvestmen composition: genus, intermediate resolution, indicator taxa, and subfamily. The number of harvestmen species recorded was significantly different between Seasonal Semideciduous Forest and Costal Atlantic Rainforest. The same relationship was also observed the same relationship was observed when we consider genus and intermediate resolution. Our results suggest the use of genus as a substitute for richness and composition of harvestmen for reducing monitoring costs and providing evaluation in a shorter time and a more practical way.  相似文献   

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Strategies are needed for reconciling competing demands at the regional level when areas are to be selected for protection and there are associated costs, possibly equivalent to forgone development opportunties. As an alternative to the fixed scaling (or weighting) of costs and benefits required by cost-benefit analysis, multi-criteria analyses allow the exploration of alternative weightings and a summary trade-off curve to determine preferred solutions. For alternative sets of areas, total cost could be plotted against total represented biodiversity, but a more consistent approach should look at trade-off space at the level of individual areas. For a given weighting, an area is assigned protection if and only if its contribution to total biodiversity, CB, exceeds its equivalent cost, EC (in biodiversity units). Because CB for a given area depends on which other areas are also protected, it can be more or less than EC. Here we develop an iterative strategy for selecting areas, such that, for a given weighting, an area is in the final protected set if and only if its final CB value is greater than its EC value. Sensitivity analysis is used to identify those areas that: (1) are assigned protection even when low weight is given to biodiversity, or (2) are not assigned protection even when high weight is given to biodiversity. This approach is applicable in principle to any surrogate measure for biodiversity; here examples are presented in which environmental data are summarized as an environmental space.  相似文献   

6.
Biodiversity priority areas together should represent the biodiversity of the region they are situated in. To achieve this, biodiversity has to be measured, biodiversity goals have to be set and methods for implementing those goals have to be applied. Each of these steps is discussed. Because it is impossible to measure all of biodiversity, biodiversity surrogates have to be used. Examples are taxa sub-sets, species assemblages and environmental domains. Each of these has different strengths and weaknesses, which are described and evaluated. In real-world priority setting, some combination of these is usually employed. While a desirable goal might be to sample all of biodiversity from genotypes to ecosystems, an achievable goal is to represent, at some agreed level, each of the biodiversity features chosen as surrogates. Explicit systematic procedures for implementing such a goal are described. These procedures use complementarity, a measure of the contribution each area in a region makes to the conservation goal, to estimate irreplaceability and flexibility, measures of the extent to which areas can be substituted for one another in order to take competing land uses into account. Persistence and vulnerability, which also play an important role in the priority setting process, are discussed briefly.  相似文献   

7.
Although the aim of conservation planning is the persistence of biodiversity, current methods trade-off ecological realism at a species level in favour of including multiple species and landscape features. For conservation planning to be relevant, the impact of landscape configuration on population processes and the viability of species needs to be considered. We present a novel method for selecting reserve systems that maximize persistence across multiple species, subject to a conservation budget. We use a spatially explicit metapopulation model to estimate extinction risk, a function of the ecology of the species and the amount, quality and configuration of habitat. We compare our new method with more traditional, area-based reserve selection methods, using a ten-species case study, and find that the expected loss of species is reduced 20-fold. Unlike previous methods, we avoid designating arbitrary weightings between reserve size and configuration; rather, our method is based on population processes and is grounded in ecological theory.  相似文献   

8.

Aim

Large ‐ scale diversity patterns are generated by different but not mutually exclusive mechanisms. However, understanding of multiple facets of diversity and their determinants in the freshwater realm remains limited. Here, we characterized the geographical gradients, hotspots and spatial congruence of three facets of freshwater molluscan diversity and evaluated the relative importance of three different underlying mechanisms related to the energy, area/environmental heterogeneity and dispersal/historical hypotheses.

Location

China.

Methods

Species richness (SR), functional richness (FR) and taxonomic distinctness (TD, a proxy of phylogenetic diversity) were calculated for 212 drainage basins with a total of 313 molluscan species. Spatial congruence between the diversity facets was evaluated with Pearson correlation coefficient and overlap among hotspots. Multiple linear regression models and variation partitioning were used to assess the relative importance of different mechanisms.

Results

Hotspots of SR and FR were mainly concentrated in the Yangtze River and Huai River basins, while high TD values were patchily distributed across China. We found extremely low spatial congruence between TD and both SR and FR, while there was relatively high concordance between SR and FR. All diversity facets were best explained by the dispersal/historical hypothesis with strong unique effects, followed by the factors related to the energy hypothesis. The area/ environmental heterogeneity hypothesis was only weakly supported.

Main conclusions

We found a potentially strong influence of dispersal limitation and evolutionary history on the geographical diversity gradients of Chinese molluscs. This finding contrasts with the general finding that energy‐related factors are the strongest correlates of diversity patterns at large spatial scales. Moreover, our results do not support the idea that using any one diversity component as a surrogate of the others in developing conservation strategies. Instead, an integrative approach embracing multiple facets of diversity should be adopted in the conservation of freshwater biodiversity.
  相似文献   

9.
We analyse optimal and heuristic place prioritization algorithms for biodiversity conservation area network design which can use probabilistic data on the distribution of surrogates for biodiversity. We show how an Expected Surrogate Set Covering Problem (ESSCP) and a Maximal Expected Surrogate Covering Problem (MESCP) can be linearized for computationally efficient solution. For the ESSCP, we study the performance of two optimization software packages (XPRESS and CPLEX) and five heuristic algorithms based on traditional measures of complementarity and rarity as well as the Shannon and Simpson indices of α‐diversity which are being used in this context for the first time. On small artificial data sets the optimal place prioritization algorithms often produced more economical solutions than the heuristic algorithms, though not always ones guaranteed to be optimal. However, with large data sets, the optimal algorithms often required long computation times and produced no better results than heuristic ones. Thus there is generally little reason to prefer optimal to heuristic algorithms with probabilistic data sets.  相似文献   

10.
分子生态学研究与运行多样性保护   总被引:7,自引:1,他引:7  
分子生态学的发展揭开了生物多样性保护研究的新篇章,分子技术的应用克服了传统生态学法中的一些难题,如野外调查周期长,分辨率有限,实验条件不易控制等,应用各种分子标记(如:RFLP,VNTR,RAPD,DNA测序等)可以分析种群地理格局和异质种群动态,确定种群间的基因流,研究瓶颈效应对种群的影响以及确定个体间的亲缘关系等等,所有这些研究都是指导物种保护和淑危种群的恢复所必要的,种或品系特异性的分子标记技术能够解决形态分类中的模糊现象,确定基于遗传物质的谱系关系,还可以用来分析近缘种间杂交问题,这些问题的解决有助于确定物种优先保护顺序,选择保护地工,近年来引起重视的主要组织人性复合体(MHC)NDA异分析可能会在研究种群对疾病的易感性第一系列种群特异性问题方面非常有用,随着分子技术的不断发展,会有更多的保护生物学问题得到解决,尤其是结合野外调查统计数据应用多个分子标记对目标种群进行研究,所得到的结果会更精确,更有说服力。  相似文献   

11.
Techniques for the rapid quantification of tropical biodiversity are of critical importance in deciding where to invest scarce conservation resources. Here we describe a simple survey method for assessing species-level richness of a poorly known plant group, the pteridophytes. We then illustrate the use of a powerful, rarefaction- based technique of controlling for inevitable differences in sampling effort to calculate the relative species richness of our study sites. Lastly, we explore how closely observed patterns of relative species richness of Ugandan forests are correlated with a suite of simple environmental variables. We find that fully 75% of the variance in our estimate of fern diversity can be predicted from just two measures: soil fertility (scored as C/N ratio, itself related to rainfall); and distance from the nearest putative Pleistocene refugium.  相似文献   

12.
李建华  王献溥  许立明  覃海宁   《广西植物》2007,27(2):211-216
广西西部石灰岩地区包括北热带、南亚热带和中亚热带的广阔范围,生物多样性和文化多样性的丰富性和独特性不仅在中国,而且在世界上都称得上是一个独一无二的区域。但是,长期以来,对它的研究并不充分,资源管护能力亟待提高,仍处于一种比较贫困的状态。为此,集中相应的人力物力,加大保护的力度并和区域经济的可持续发展密切结合起来是一项迫切的任务。该文主要对这个区域生物多样性保护的基本情况和发展途径作简要介绍,期待引起各方面的关注。  相似文献   

13.
Biodiversity assessment requires that we use surrogate information in practice to indicate more general biodiversity patterns. ‘ED’ refers to a surrogates framework that can link species data and environmental information based on a robust relationship of compositional dissimilarities to ordinations that indicate underlying environmental variation. In an example analysis of species and environmental data from Panama, the environmental and spatial variables that correlate with an hybrid multi‐dimensional scaling ordination were able to explain 83% of the variation in the corresponding Bray Curtis dissimilarities. The assumptions of ED also provide the rationale for its use of p‐median optimization criteria to measure biodiversity patterns among sites in a region. M.B. Araújo, P.J. Densham & P.H. Williams (2004, Journal of Biogeography 31 , 1) have re‐named ED as ‘AD’ in their evaluation of the surrogacy value of ED based on European species data. Because lessons from previous work on ED options consequently may have been neglected, we use a corroboration framework to investigate the evidence and ‘background knowledge’ presented in their evaluations of ED. Investigations focus on the possibility that their weak corroboration of ED surrogacy (non‐significance of target species recovery relative to a null model) may be a consequence of Araújo et al.'s use of particular evidence and randomizations. We illustrate how their use of discrete ED, and not the recommended continuous ED, may have produced unnecessarily poor species recovery values. Further, possible poor optimization of their MDS ordinations, due to small numbers of simulations and/or low resolution of stress values appears to have provided a possible poor basis for ED application and, consequently, may have unnecessarily favoured non‐corroboration results. Consideration of Araújo et al.'s randomizations suggests that acknowledged sampling biases in the European data have not only artefactually promoted the non‐significance of ED recovery values, but also artefactually elevated the significance of competing species surrogates recovery values. We conclude that little credence should be given to the comparisons of ED and species‐based complementarity sets presented in M.B. Araújo, P.J. Densham & P.H. Williams (2004, Journal of Biogeography 31 , 1), unless the factors outlined here can be analysed for their effects on results. We discuss the lessons concerning surrogates evaluation emerging from our investigations, calling for better provision in such studies of the background information that can allow (i) critical examination of evidence (both at the initial corroboration and re‐evaluation stages), and (ii) greater synthesis of lessons about the pitfalls of different forms of evidence in different contexts.  相似文献   

14.
The adequate selection of indicator groups of biodiversity is an important aspect of the systematic conservation planning. However, these assessments differ in the spatial scales, in the methods used and in the groups considered to accomplish this task, which generally produces contradictory results. The quantification of the spatial congruence between species richness and complementarity among different taxonomic groups is a fundamental step to identify potential indicator groups. Using a constructive approach, the main purposes of this study were to evaluate the performance and efficiency of eight potential indicator groups representing amphibian diversity in the Brazilian Atlantic Forest. Data on the geographic range of amphibian species that occur in the Brazilian Atlantic Forest were overlapped to the full geographic extent of the biome, which was divided into a regular equal‐area grid. Optimization routines based on the concept of complementarily were applied to verify the performance of each indicator group selected in relation to the representativeness of the amphibians in the Brazilian Atlantic Forest as a whole, which were solved by the algorithm “simulated annealing,” through the use of the software MARXAN. Some indicator groups were substantially more effective than others in regard to the representation of the taxonomic groups assessed, which was confirmed by the high significance of the data (F = 312.76; < 0.01). Leiuperidae was considered as the best indicator group among the families analyzed, as it showed a good performance, representing 71% of amphibian species in the Brazilian Atlantic Forest (i.e., 290 species), which may be associated with the diffuse geographic distribution of their species. In this sense, this study promotes understanding of how the diversity standards of amphibians can be informative for systematic conservation planning on a regional scale.  相似文献   

15.
城市公园和郊区公园生物多样性评估的指标   总被引:17,自引:0,他引:17  
陈波  包志毅 《生物多样性》2003,11(2):169-176
随着城市化进程的加快,城市的生物多样性不可避免地受到城市化的各种影响,城市及其郊区的生物多样性保护越来越受到人们的重视。城市公园与郊区公园中往往具有高度多样化的生境,并保存着某些自然植被片段和动物物种,那里的生物多样性较高。可见,在城市和郊区的生物多样性保护中,公园生物多样性的保护是一个非常关键的环节,而对其生物多样性的评估又是有效保护的基础。目前,我国生物多样性评估方面的研究工作多集中于物种水平,而对生境的研究较少,但实践证明,保护生境比保护物种更为重要。本文介绍了比利时学者Hermy & Cornelis在比利时西佛兰德省的Loppem市立公园的保护实践中构建的一种对城市公园和郊区公园中的生物多样性进行评估的方法。该方法从两个方面展开:生境多样性和物种多样性。在生境水平上,首先对各种生境单元进行分类,这些单元被分为面状、线状和点状要素。针对每种要素,分别计算了Shannon-Wiener多样性指数和饱和度指数。饱和度指数是实际的多样性指数与最大可能的多样性指数之比。在物种水平上,使用了物种数、Shannon-Wiener多样性指数和饱和度指数来评估公园中的高等植物、蝴蝶、两栖动物和饲养的鸟类等物种。这样,就获得了20个生物多样性指标,根据这些指数就可以对Loppem市立公园内的生物多样性进行评估。结合我国生物多样性评估工作的实际要求,文章最后对上述方法进行了讨论,指出该方法对我国公园的生物多样性评估工作具有借鉴意义,但在运用时各地需要结合本地的实际情况。  相似文献   

16.
Three speciose plant families (Asteraceae, Fabaceae s.l. , and Poaceae) are evaluated for their appropriateness as predictors of overall regional patterns of plant diversity in Mexico. These families fulfil criteria for usefulness as indicators advocated by several authors, such as adequate taxonomic knowledge, wide geographical distribution, and occurrence in different plant communities. Known richness was determined from a database including 17,903 species from floristic inventories, review of taxonomic literature, and the study of herbarium specimens. Mexico was divided into 253 cells, each 1° latitude by 1° longitude; for each cell, total plant diversity and number of species in each predictor's family were determined. In addition, each species was categorized by 'preferred' vegetation type (temperate forest, dry tropical forest, humid tropical forest, xerophytic scrubland). Both multiple and simple regression models show that the three families are good predictors of total vascular floristic richness. Fabaceae s.l. has the highest semipartial correlations for all multiple models except with the xerophytic scrubland data set, for which it shares the highest values with Poaceae. Univariate models also predict satisfactorily the vascular floristic richness, especially when Fabaceae s.l. is used as the predictor, and the effect of vegetation type is included. Our results indicate that these three families can be used as potential predictors for total vascular plant species richness in Mexico although Fabaceae s.l. is the best predictor.  相似文献   

17.
Data from 3991 records of museum collections representing 421 species of plants, arthropods, amphibians, fish, and primates were analyzed with GIS to identify areas of high species diversity and endemism in Amazonia. Of the 472 1 × 1° grid cells in Amazonia, only nine cells are included in the highest species diversity category (43–67 total species) and nine in the highest endemic species diversity category (4–13 endemic species). Over one quarter of the grid cells have no museum records of any of the organisms in our study. Little correspondence exists between the centers of species diversity identified by our collections-based data and those areas recommended for conservation in an earlier qualitative study of Amazonian biodiversity. Museum collections can play a vital role in identifying species-rich areas for potential conservation in Amazonia, but a concerted and structured effort to increase the number and distribution of collections is needed to take maximum advantage of the information they contain.  相似文献   

18.
北京山地植物多样性优先保护地区评价   总被引:2,自引:2,他引:2  
邢韶华  林大影  鲜冬娅  崔国发 《生态学报》2009,29(10):5299-5312
为促进北京市植物多样性的保护及自然保护区的合理建设与布局,以2001~2006年间在北京市13个自然保护区、森林公园或者风景名胜区内实地调查的1168个样地数据为基础,根据在北京市分布的25种珍稀濒危植物种,以及丰富度高的群落类型、面积较大的天然森林群落类型和具有重要生态功能的森林群落的评定结果,采用等级赋值的方法,利用地理信息系统软件从植物物种和植物群落方面综合评定了北京市山地植物多样性的优先保护地区.评定出综合优先保护地区总面积为184474.64hm2,约占市国土面积的11.25%,其中一级优先保护地区总面积24850.50hm2,二级优先保护地区总面积78606 60hm2,三级优先保护地区总面积81017.54hm2.优先保护地区主要分布于怀柔区、延庆县、房山区和密云县等远郊区县,结合北京市自然保护区分布现状,提出了北京市自然保护区建设优化方案.  相似文献   

19.
农业生物多样性保护的景观规划途径   总被引:9,自引:0,他引:9  
农业生物多样性保护不仅关系到农业可持续发展,也是物种多样性保护的重要组成部分.近年来,生物多样性保护更加强调通过景观规划途径来实现.本文在回顾国内外关于景观结构对生物多样性影响一般性结论和研究结果的基础上,从景观、地块间、地块内3个尺度分别探讨了农业生物多样性保护的景观规划途径,并建议可以通过采取如下途径有效地保护农业生物多样性:1)在景观尺度上,维持较高比例的自然、半自然生境,注意农用地和种植作物的多样化,注重树篱等廊道生境的保护和建设;2)在地块间尺度上,构建农田边缘地带;3)在地块内尺度上,合理地规划作物种植密度、作物空间分布及采取间套作、轮作等方式.此外,大尺度景观规划途径的实施还需要诸如自然保护计划、土地利用规划及生态补偿等相关政策措施的配套与支持.  相似文献   

20.
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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