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1.
Conservation of biodiversity will necessitate choices among areas, taxa, and land-use patterns. Lack of data on distribution and pattern in biodiversity makes these difficult decisions even more problematic for those charged with the conservation and sustainable use of the diversity of life. Quantitative methods have promise in helping with this task in that they allow people to make their values explicit, and they also allow representation and comparison of many different types of data. In this article I examine patterns of species richness and range-size rarity, or endemism, in the Neotropics with a data set from the genusSolanum (Solanaceae). Distribution data for 180 species of forest-dwelling solanums were analyzed. Patterns of species richness, range-size rarity (endemism), and several area-selection methods were examined. Montane areas are relatively rich both in all species and in endemic species, with maximal peaks in the Andes. The peak of species richness coincides with the domain (i.e., continental) midpoint (9°30′ S latitude), suggesting that the pattern observed may be partly due to the geometry of species ranges. TheSolanum results are compared with those obtained for other taxonomic groups in the Neotropics, and problems with quantitative data sets in conservation are discussed. Collecting deficit, parochial taxonomy, and habitat destruction, both historical and current, are all factors that will affect the utility of such analyses. It is clear that if conservation is to work on the ground, we need to know more about what occurs in the montane Neotropics and that continued work at a basic taxonomic level is essential to our ultimate ability to conserve biological diversity.  相似文献   

2.
The three sections of this paper report on i) new species, ii) new records for the Flora Zambesiaca region and for Mozambique and iii) expansion of distributions of species previously thought to be endemic to particular mountains. Specimens have been collected from three mountains in north-central Mozambique visited during a collecting programme from 2006 to 2008 investigating the conservation value of the biodiversity of currently unprotected areas. Three new species: Crotalaria namuliensis, Isoglossa namuliensis and Helixanthera schizocalyx are described. Five taxa not previously recorded from the Flora Zambesiaca region are here recorded as new records for the region and 31 taxa are listed from Mozambique for the first time, including five taxa previously thought to be Malawi mountain endemics. The number of range extensions recorded from these Mozambican mountains is evidence of the paucity of specimens collected from this part of Mozambique and shows the need for continued collection in order to clarify the distributions of this region’s rarest species.  相似文献   

3.
Grassland birds are among the most globally threatened bird groups due to substantial degradation of native grassland habitats. However, the current network of grassland conservation areas may not be adequate for halting population declines and biodiversity loss. Here, we evaluate a network of grassland conservation areas within Wisconsin, U.S.A., that includes both large Focal Landscapes and smaller targeted conservation areas (e.g., Grassland Bird Conservation Areas, GBCAs) established within them. To date, this conservation network has lacked baseline information to assess whether the current placement of these conservation areas aligns with population hot spots of grassland‐dependent taxa. To do so, we fitted data from thousands of avian point‐count surveys collected by citizen scientists as part of Wisconsin''s Breeding Bird Atlas II with multinomial N‐mixture models to estimate habitat–abundance relationships, develop spatially explicit predictions of abundance, and establish ecological baselines within priority conservation areas for a suite of obligate grassland songbirds. Next, we developed spatial randomization tests to evaluate the placement of this conservation network relative to randomly placed conservation networks. Overall, less than 20% of species statewide populations were found within the current grassland conservation network. Spatial tests demonstrated a high representation of this bird assemblage within the entire conservation network, but with a bias toward birds associated with moderately tallgrasses relative to those associated with shortgrasses or tallgrasses. We also found that GBCAs had higher representation at Focal Landscape rather than statewide scales. Here, we demonstrated how combining citizen science data with hierarchical modeling is a powerful tool for estimating ecological baselines and conducting large‐scale evaluations of an existing conservation network for multiple grassland birds. Our flexible spatial randomization approach offers the potential to be applied to other protected area networks and serves as a complementary tool for conservation planning efforts globally.  相似文献   

4.
“The New Red List of the Italian Flora” includes all the Italian policy species and other species of known conservation concerns for a total of 400 taxa, 65% of which are threatened with extinction. The Red List is based on a huge georeferenced data-set useful for conservation purposes.  相似文献   

5.
Setting priorities in biodiversity conservation requires that explicit, efficient and appropriate methods are developed and made available to conservation managers. The principle of complementarity is fundamental to the most efficient of these methods. Given a goal of only a single representation of each taxon, complementarity analysis of data sets of owls, hawkmoths and tiger beetles in Thailand yields near-minimum sets of 6, 14 and 34 areas, respectively. The consensus of these sets comprises 48 areas. However, when the data are combined into a single data set, complementarity analysis gives a more efficient solution of 46 areas. Over 90% of the owls, hawkmoths and tiger beetles are already represented as a minimum of one population within the current protected areas network of Thailand. However, an additional 18 areas are still required for complete representation. Several of these additional areas are discussed and their potential contribution to biodiversity conservation in Thailand examined. Khao Pok Yo and Doi Pa Hom Pok are noted as being of particular importance. The case of Sanpatong emphasizes the need to remain aware of the biology and ecology of the species under study.  相似文献   

6.
The 21st century has witnessed a rapid development in technologies of molecular biology and computer informatics. Fundamental changes have taken place in means and methods in which humans take cognition of the world. Based on the currently available eFlora and combining this with elements of next generation sequencing techniques, DNA sequence data, geographical information system data and computer information technology, the next-generation Flora (iFlora) is bursting. Through a series of key technological innovations and integrations, the main objective of iFlora is to construct the next-generation Flora, which will fulfill the function of accurately and rapidly identifying species and acquiring species related digital information. iFlora will greatly advance the development of plant taxonomy, phylogenetics, evolutionary biology, ecology, biogeography, conservation biology and other related disciplines. Furthermore, iFlora will be a valuable tool for biodiversity conservation and sustainable utilization of biological resources, ecological security, public education and services, and will profoundly promote public understanding of biodiversity. The application of iFlora will tremendously nurture and boost the taxasphere and bioliterate world, and will be a new focal point that may reshape modern botany at the global and regional levels.  相似文献   

7.
Populations of naturally growing woody species valued for their contribution to human livelihoods are threatened with extinction. Most at risk are those existing in human inhabited areas outside protected areas that are subjected to high population pressure and to a variety of land use demands. The sustainable utilization of these plants requires as a first step knowledge, including, their ecology and an understanding of the peoples attitudes to conservation. This study was conducted to generate data that would contribute to the management for conservation and sustainable use of woody resources. The study objectives were to document local knowledge covering the uses, status, threats, habitats and management solutions of woody species; determine the abundances, distribution and population structure of 16 woody species, and assess the conservation status of the selected woody species. The study was carried out in Gadumire Sub-county, Uganda using both an ethnobotanical approach and quantitative ecological methods. The species are multipurpose and are exploited to satisfy different subsistence needs. They had population densities ranging between 3.6 and 2630 individuals ha−1, and distributions ranging between 0.3 and 39.5%. The species Acacia hockii, Albizia zygia, Acacia seyal, Markhamia lutea and Albizia coriaria had a good conservation status. The remainder of the species appear threatened either because they had low densities, frequencies or less steep size class distribution (SCD) slopes. Securidaca longipedunculata Fres. was not encountered at all in the study plots. Community perceptions collaborated the measured population dynamics. The major threats believed to be impacting the species by the community are the growing human population, expanding crop agriculture, poor harvesting methods and over-exploitation of the species.  相似文献   

8.
Management and conservation actions in marine-protected areas require baselines for monitoring threatened marine fauna such as elasmobranchs. This article provides evidence of the occurrence of 34 species of elasmobranchs (21 sharks and 13 batoids) in the Malpelo Flora and Fauna Sanctuary, Colombia, including five new records of sharks and three of rays. From 1987 to 2021, new records were obtained by underwater visual census using SCUBA, manned submersibles and deep-ocean cameras to depths of up to 2211 m. Of the recorded species, 21 are considered as threatened taxa (64%) by the IUCN, making the Malpelo Flora and Fauna Sanctuary an essential conservation area for this highly threatened group of species.  相似文献   

9.
10.
Although phylogenetic diversity has been suggested to be relevant from a conservation point of view, its role is still limited in applied nature conservation. Recently, the practice of investing conservation resources based on threatened species was identified as a reason for the slow integration of phylogenetic diversity in nature conservation planning. One of the main arguments is based on the observation that threatened species are not evenly distributed over the phylogenetic tree. However this argument seems to dismiss the fact that conservation action is a spatially explicit process, and even if threatened species are not evenly distributed over the phylogenetic tree, the occurrence of threatened species could still indicate areas with above average phylogenetic diversity and consequently could protect phylogenetic diversity. Here we aim to study the selection of important bird areas in Central Asia, which were nominated largely based on the presence of threatened bird species. We show that although threatened species occurring in Central Asia do not capture phylogenetically more distinct species than expected by chance, the current spatially explicit conservation approach of selecting important bird areas covers above average taxonomic and phylogenetic diversity of breeding and wintering birds. We conclude that the spatially explicit processes of conservation actions need to be considered in the current discussion of whether new prioritization methods are needed to complement conservation action based on threatened species.  相似文献   

11.
董莉娜  刘演 《广西植物》2019,39(1):16-39
秋海棠属(Begonia L.)隶属于葫芦目(Cucurbitales)秋海棠科(Begoniaceae),有1 800余种,是世界第六大属,主要分布于美洲、非洲和亚洲的热带和亚热带地区,具有极高的观赏价值,亦可作为药用、食用、饮料和饲料等。我国有秋海棠属植物近300种,主要分布于我国的云南和广西等长江以南地区,其中云南有秋海棠属植物100余种。近年来,随着广西地区秋海棠属植物野外调查的不断深入,陆续发现并发表了大量秋海棠属新类群,使得广西产秋海棠属植物数目已超出1991年《广西植物志》(第一卷)收录的19种,因此亟需对发表于不同期刊中的类群进行系统地整理和汇总。鉴于此,该文通过查阅文献资料和考证标本信息,整理并汇总了广西产秋海棠属植物共84种,包括2个变种、11个亚种和46个特有种,新增的65种为《广西植物志》(第一卷)中未收录的类群,并补充了这些类群的特征集要、凭证标本信息和属下分组概况,为今后开展秋海棠属植物的分类修订以及系统学、进化生物学和保护生物学等研究提供了参考依据。  相似文献   

12.
Feeding ecology is an important factor for the survival of a species and knowledge of its parameters is a prerequisite for successful conservation work. In this study we describe the feeding ecology of the endemic Seychelles Black Parrot Coracopsis barklyi on Praslin, Seychelles, the only island on which this parrot is resident. We compared two methods to evaluate feeding choices: incidental observations and feeding walks on 25 transects in all habitat types. Black parrots fed on 46 different species, bringing the total number of known food plants to 53 species. They predominantly consumed endemic and native species (58% of observed feeding bouts), mainly their fruit pulp (in 68% of feeding bouts), followed by buds (15%) and seeds (37%) with occasional observations of leaves, bark and scale insects. The incidental method rendered many more observed bouts than the transect approach and the ratios of consumed species differed between methods but the transect results are regarded as more representative. The incidental method is not suitable for quantitative conclusions but complements the transect method, providing information about rarely occurring feeding events.  相似文献   

13.
Minimum complementary sets of sites that represent each species at least once have been argued to provide a nominal core reserve network and the starting point for regional conservation programs. However, this approach may be inadequate if there is a tendency to represent several species at marginal areas within their ranges, which may occur if high efficiency results from preferential selection of sites in areas of ecological transition. Here we use data on the distributions of birds in South Africa and Lesotho to explore this idea. We found that for five measures that are expected to reflect the location of areas of ecological transition, complementary sets tend to select higher values of these measures than expected by chance. We recommend that methods for the identification of priority areas for conservation that incorporate viability concerns be preferred to minimum representation sets, even if this results in more costly reserve networks.  相似文献   

14.
On the basis of extensive field studies throughout Greece and of about 19 500 field and literature records extracted from the Flora Hellenica Database, we provide the first survey of wild plant species of traditional agriculture in Greece (hereafter TA species). For each of the 138 taxa, life form, rareness (on national scale), local abundance (habitat occupancy) and regional restrictedness are given. We infer population trends from the record chronology of the taxa in the Flora Hellenica Database, and we assess the Red List status of the arable plants using IUCN criteria. According to current knowledge, two TA species are presumed Extinct in Greece and seven Critically Endangered. Almost half of the species are threatened, including 46 Vulnerable and 15 Endangered taxa. There is a high proportion of locally distributed taxa among Greek TA species. Distribution patterns show a pronounced south–north gradient, and the unique character of the East Aegean arable flora is revealed. Most arable species are annuals (83%). Perennial herbs, mostly bulbous or tuberous plants (geophytes), account for 17%, and a major proportion of the latter must be considered as threatened at different levels. The chronology of decline of certain TA species is reflected by processes of agricultural intensification and regional urbanization. We suggest conservation measures for the unique arable flora of Greece. To reflect the geographical and ecoregional variation, in situ measures should focus on areas with species‐rich arable fields in all phytogeographical regions of Greece. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175 , 607–623.  相似文献   

15.
Patterns of plant diversity along the altitudinal gradient of Tianshan in central Xinjiang, China were examined. Plant and environment characteristics were surveyed from higher, south of Bogeda peak, to lower, north of Guerbantonggute desert. There were a total of 341 vascular plant, 295 herbage, 41 shrub, and seven tree species in the sampled plots. The plant richness of vegetation types generally showed a unimodal pattern along altitude, with a bimodal change of plant species number at 100-m intervals of altitudinal samples. The two belts of higher plant richness were in transient areas between vegetation types, the first in areas from dry grass to forest, and the second from forest to sub-alpine grass and bush. The beta diversity varied with altitudinal changes, with herbaceous species accounting for most species, and thus had similar species turnover patterns to total species. Matching the change of richness of plant species to environmental factors along altitude and correlating these by redundancy analysis revealed that the environmental factors controlling species richness and its pattern were the combined effects of temperature, precipitation, soil water, and nutrition. Water was more important at low altitude, and temperature at high altitude, and soil chemical and physical characters at middle altitudes. This study provides insights into plant diversity conservation of Bogeda Natural Reserve Areas in Tianshan Mountain. Nomenclatures: the scientific name for plants follows Flora of China (Compiling Committee of Flora of China).  相似文献   

16.
A method is presented whereby regional species are scored and ranked in order of regional conservation importance according to a number of different but complementary 'rarity' criteria. Approaches for determining regional occupancy (RO), relative taxonomic distinctiveness (RTD), relative endemism (RE) and relative vulnerability (RV) rankings for regional faunas are proposed. The continuous variable approach and resultant positively skewed 'rarity' scores suggest easy identification of regional priority species. These methods are collectively applied to a regional mammalian fauna in order to prioritize species for conservation action using a regional priority score (RPS). The proposed method is a comparative relational approach aimed at determining which species require the establishment of viable populations within a regional context. The two species afforded highest RPSs for the Transvaal region, South Africa, are Gunning's golden mole Amblysomus gunningi and Juliana's golden mole A. julianae. These two species are true endemics, with geographic ranges completely restricted to the region. Also of high regional conservation importance are the four-toed elephant shrew Petrodromus tetradactylus, pangolin Manis temminckii and aardvark Orycteropus afer. Although these species have low RE scores, they have high RTD and RV scores. The equal weightings given to the four components of 'rarity' ensures that species achieving a high score in any of these categories will be considered for regional priority listing. This approach is simple, explicit and repeatable, circumventing problems of scale.  相似文献   

17.
The use of quantitative measures to select priority areas for conservation has been in practice since the early 1980s. However, the relative efficiency of different methods for identifying priority areas is still the subject of debate. Here, using the distribution data of 556 Rhododendron species in China with high spatial resolution, we evaluated the performance of the two commonly used methods, i.e. hotspot and complementarity and selected the efficient method to select priority areas for the conservation of Rhododendron in China. By overlaying the priority areas map with the locations of protected areas, we also identified the regions not covered by current protected areas (i.e. conservation gaps). We found that the complementarity method selected less number of grid cells to capture an equivalent number of species and hence had higher efficiency and representativeness than the commonly used hotspot method. Moreover, the complementarity method was better at capturing the range-restricted species than the hotspot method. Based on the complementarity method, we identified 61 grid cells of 50?×?50 km as priority areas for Rhododendron conservation in China. Among these priority areas, only about 50% grid cells were located in the hotspot areas (e.g. Hengduan Mountains), and 14% grid cells were outside the current protected area network. Our findings suggest that, despite its popularity and ease of implementation, the sites selected by hotspot algorithm may not necessarily be the best sites to allocate conservation efforts. Since the identification of priority areas in China has largely been based on the hotspot method, the current study has revived the need to reassess the priority areas for other taxonomic groups too. More importantly, our findings have emphasized the need to expand the conservation priorities from Hengduan Mountains to south and southeast China as well.  相似文献   

18.
基于物种的大尺度生物多样性热点研究方法   总被引:2,自引:1,他引:2  
生物多样性热点是建立保护区、制定保护决策的依据,是生物保护研究的热点问题之一。基于物种的研究方法是大尺度陆地生物多样性热点的主要研究方法,但数据的缺乏限制了直接根据物种丰富度确定热点的方法,因此研究中经常采用其他方法间接的反映物种情况,介绍了4种主要的基于物种的替代方法:指示种、高级分类单元、环境模型和景观异质性,详细阐述了各种方法存在的利弊,并从数据的可获取性、操作的便捷性和对物种特征的反映3个方面对各种方法进行了评价。任何单一的方法都无法准确反映出生物多样性热点的真实分布。合适的研究方法是权衡研究目的、时间和资金的结果,建议选择优势互补的多种方法。  相似文献   

19.
With the increasing concern about species conservation, a need exists for quantitaive characterization of species' geographic range and their borders. In this paper, we survey tools appropriate for the quantification of static spatial patterns related to geographical ranges and their borders. We then build on these static methods to consider the problem of changes in geographic range through time. Methods discussed are illustrated using lark sparrow data from the North American Breeding Bird Survey. While there is no such thing as the "best" or "only" method to analyze species geographical range and border, we show that a series of methods can be used in sequence to provide complementary and useful quantitative information for species occupancy of range. Indeed, the location of species' borders estimated at different times can be compared to identify locations where species expand or go locally extinct. The ability to delineate accurately species' ranges will be useful to conservation biologists, managers and ecologists.  相似文献   

20.
Aim New protected areas should consider safeguarding high conservation value sites based on multiple criteria and not just the presence of a single endangered or charismatic species. However, the extent to which complementary criteria coincide is usually unknown. We use the case of Guaiacum sanctum (Zygopyllaceae), an endangered timber tree species, to explore whether the protection of forests where this species is most abundant would meet other complementary conservation goals, such as capturing regional plant biodiversity, protecting other threatened/endemic species or safeguarding ecosystem services. Location Yucatan Peninsula, southern Mexico. Methods We conducted an analysis of the structure, composition and diversity of tree communities (including stems ≥5 cm dbh) at eight G. sanctum forest sites. We identified endemic and threatened tree species and quantified above‐ground tree biomass and carbon storage in these G. sanctum forests. Results Guaiacum sanctum forests contain 35–59 tree species on plots as small as 1000 m2. The species composition of tree communities changed rapidly (high β‐diversity) across soil boundaries and rainfall regimes. Twenty‐one endemic and eight threatened tree species were recorded in our inventories. Individuals of G. sanctum represented up to 55% of the above‐ground carbon for trees ≥5 cm dbh. The high basal area of G. sanctum forests plus the high wood density, abundance, large size and longevity (more than 500 years) of G. sanctum and other tree species enhance the potential importance of these forests for carbon storage. Main conclusions A conservation strategy focused on protecting important populations of G. sanctum in the Yucatan Peninsula would have significant co‐benefits for conservation of regional tree species biodiversity and provision of critical ecosystem services. Our study illustrates a multiple criteria approach useful for the selection of areas with high conservation value on the basis of endemic, threatened species, species richness and ecosystem services.  相似文献   

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