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1.
Abstract

Progress is reported on the systematics and biogeography of some small land snails in Australasia. Observed patterns of dispersal and massings of taxa appear to support basic concepts in panbiogeographic methodology. The role of the amateur in science is related to the use of computers, curatorial systems, and the current political environment for science.  相似文献   

2.
Abstract

An investigation of flightlessness in the Rallidae led me to question the theories of Olson (1973); that all rails in the genus Gallirallus were distributed over their present range by recent flighted dispersal; and that flightlessness is a recent process conferred by the paedomorphic process neoteny. The current distribution of some members of Gallirallus (Olson 1973a) are interpreted using the panbiogeographic method of Croizat (1958, 1958a). This method indicates that the distribution of some rails is similar to other biota. I suggest the group may be ancient, and its distribution the result of vicariism. Consequently, the evolution of flightless morphology need not be fast, and the flightless rails on different land masses could be the result of flightless radiations.  相似文献   

3.
Abstract

New Zealand’s official conservation science framework, the Protected Natural Areas Programme (PNA), is evaluated in relation to current biogeographic/systematic methods and principles with reference to philosophy, taxonomy, information content, and historical geological/biological relations. The PNA Programme and its parent International Union for Conservation of Nature and Natural Resources (IUCN) framework is based on a phenetic system of classification that does not reflect process (phylogenetic) characters of ecological systems. The PNA philosophy of conservation science is shown to be essentialist, rooted in traditional medieval Western metaphysics, and out of step with current developments in biogeography, systematics, and ecology. Panbiogeography is an appropriate global perspective for developing a conservation science because it meets the requirements of homology, monophyly, increased information content, and empirical testability whereas the PNA programme does not. Establishment of a Panbiogeographic Track Atlas is proposed as a suitable conservation framework for historical ecology and biogeography. The atlas could provide an empirical natural resource inventory to identify priority areas for conservation at an economically acceptable cost compared to the PNA Programme. Application of cladistic techniques to ecological and biogeographic patterns in relation to the Atlas can provide aphylogenetically sound hierarchical classification for conservation science. The potential benefits of the panbiogeographic approach for conservation education and tourism are discussed.  相似文献   

4.
Aim The large rivers of the Neotropics are considered areas of high diversity and endemism, which play an important role in the distribution patterns and evolution of Neotropical biota. Several methods have been proposed for prioritizing terrestrial conservation areas, but there has been little effort to develop models for river systems. We propose a panbiogeographical approach to identify priority areas for conservation along rivers. Location The Plata Basin rivers. Methods We compared the individual tracks (IT) of 96 snake taxa and identified the species associated with rivers using the concept of preferential direction of distribution. For each taxon, we measured the angular deviations between the line of its IT and the course of the rivers on a 100 × 100 km scaled grid. Average angular values < 45° indicated a positive association with rivers. We detected 35 taxa associated with rivers, and their IT were used to determine the generalized tracks (GT) and nodes. We applied a complementarity algorithm to identify the minimum set of nodes required to represent all species. Results Six nodes were found. The region where the High and Upper Paraná Rivers converge (Node 1) is of first priority, with 60 of 96 species. The second priority is the Lower Paraguay River and northern section of Middle Paraná River (Node 2). The third is the High Paraná, which together with Nodes 1 and 2, comprises 94% of the total species. The fourth and fifth are the High and Middle Uruguay, and the western section of the Upper Paraná and Iberá Marsh system, respectively. These five nodes include all species. Main conclusions Our results highlight the areas of particular interest for the conservation of rivers and provide a biogeographical algorithm for detecting priority conservation areas. The nodes are a biogeographical approach that allows evolutionary and ecological traits to be included in conservation assessment.  相似文献   

5.
Given species inventories of all sites in a planning area, integer programming or heuristic algorithms can prioritize sites in terms of the site's complementary value, that is, the ability of the site to complement (add unrepresented species to) other sites prioritized for conservation. The utility of these procedures is limited because distributions of species are typically available only as coarse atlases or range maps, whereas conservation planners need to prioritize relatively small sites. If such coarse‐resolution information can be used to identify small sites that efficiently represent species (i.e., downscaled), then such data can be useful for conservation planning. We develop and test a new type of surrogate for biodiversity, which we call downscaled complementarity. In this approach, complementarity values from large cells are downscaled to small cells, using statistical methods or simple map overlays. We illustrate our approach for birds in Spain by building models at coarse scale (50 × 50 km atlas of European birds, and global range maps of birds interpreted at the same 50 × 50 km grid size), using this model to predict complementary value for 10 × 10 km cells in Spain, and testing how well‐prioritized cells represented bird distributions in an independent bird atlas of those 10 × 10 km cells. Downscaled complementarity was about 63–77% as effective as having full knowledge of the 10‐km atlas data in its ability to improve on random selection of sites. Downscaled complementarity has relatively low data acquisition cost and meets representation goals well compared with other surrogates currently in use. Our study justifies additional tests to determine whether downscaled complementarity is an effective surrogate for other regions and taxa, and at spatial resolution finer than 10 × 10 km cells. Until such tests have been completed, we caution against assuming that any surrogate can reliably prioritize sites for species representation.  相似文献   

6.
Biogeographical patterns of distribution of 74 species of Asteraceae that inhabit mainly the temperate forests of eastern Mexico were studied usingtrack analysis. Five generalized tracks were identified and conservation areas proposed based on degree of complexity of floristic patterns (Luna et al., 1999) and biotic richness. The northern part of the Sierra Madre Oriental harbours a high concentration of narrowly restricted species. In this area there are four track nodes that coincide with the Mexican priority terrestrial regions (RTPs) proposed by the Comisión Nacional para el Conocimiento y Uso de la Biodiversidad (CONABIO) and with previously identified areas of importance for bird conservation (AICAs). Two more nodes are found in the central and southern part of the Sierra. With the gathered information, we propose particular selected species of Asteraceae to be included in the Mexican areas of endangered species (NOM).  相似文献   

7.
8.
In a study of the widespread Australian endemic seagrass Posidonia australis , allozyme analysis identified a wide range in population genetic structure assessed using the multilocus genotype diversity statistic ( D G). Values of D G between zero and one were obtained; however, RAPD analysis generally detected higher levels of diversity, where D G values were all greater than 0.5 ( D G = 0.67 – 1). Some populations were allozymically monomorphic using allozyme analysis yet were highly polymorphic using RAPD analysis. The differences observed between methods, particularly among allozymically uniform populations, demonstrate the importance of choosing an appropriate method when assessing genotypic diversity. Different methods may reflect different historical aspects of population processes where allozymes reflect broader-scale gene flow and population establishment and DNA fingerprinting methods such as RAPDs may reflect fine-scale local recruitment events and shorter-term population processes. Using either method alone, particularly in genotypically depauperate organisms such as seagrasses and other clonal organisms, will be problematic in assessing their population genetic potential, a parameter being used by conservation managers to decide upon management strategies in rare and endangered organisms. It is recommended that the impact of disturbance assessed using genotypic diversity measures requires more than one technique to provide the most appropriate information for designing subsequent conservation strategies.  相似文献   

9.
This paper provides a synopsis of the Chilean Asteraceae genera according to the most recent classification. Asteraceae is the richest family within the native Chilean flora, with a total of 121 genera and c . 863 species, currently classified in 18 tribes. The genera are distributed along the whole latitudinal gradient in Chile, with a centre of richness at 33°–34° S. Almost one-third of the genera show small to medium-small ranges of distribution, while two-thirds have medium-large to large latitudinal ranges of distribution. Of the 115 mainland genera, 46% have their main distribution in the central Mediterranean zone between 27°–37° S. Also of the mainland genera, 53% occupy both coastal and Andean environments, while 33% can be considered as strictly Andean and 20% as strictly coastal genera. The biogeographical analysis of relationships allows the distinction of several floristic elements and generalized tracks: the most marked floristic element is the Neotropical, followed by the antitropical and the endemic element. The biogeographical analysis provides important insights into the origin and evolution of the Chilean Asteraceae flora. The presence of many localized and endemic taxa has direct conservation implications.  相似文献   

10.
Patterns and environmental correlates of species distributions and richness are identified for Kenyan birds at a quarter degree-square scale. This information is used together with iterative complementarity analyses, which employ species richness, taxonomic dispersion and range-restrictedness, to identify priority areas for possible conservation attention. Bird species apparently not conserved by existing protected areas in Kenya are identified. Six avifaunal zones (and one transitional zone) are distinguished based on distributions of suites of bird species. Variation in biotope diversity (the number of forest and aquatic systems) accounts for 79% of the observed variation in Kenyan bird species richness. Although both rainfall and altitudinal range are significantly correlated with species richness, they only explain an additional 3% of the observed variation. The priority areas identified are situated mainly within highlands and coastal lowlands. Although few priority areas are identified in northern Kenya, this region also constitutes a priority, as it contains a suite of xeric species with habitats that are not represented elsewhere in Kenya. The papyrus yellow warbler, Chloropeta gracilirostris, William's bush lark, Mirafra williamsi, white-winged dove, Streptopelia reichenowi, and Jubaland weaver, Ploceus dichrocephalus, are identified as endemics or near-endemics that are probably not adequately conserved in Kenya at present.  相似文献   

11.
优先保护区识别对受威胁物种的多样性保护具有重要价值。基于GIS空间分析、管理及预测能力,以中国受威胁陆栖哺乳动物为对象,建立受威胁物种的分布二值网格系统;利用Dobson算法对研究区3810个网格单元进行筛除,确定全国范围下受威胁物种的优先保护区域;结合中国主要的自然保护地分布数据(国家公园和自然保护区),采用保护空缺方法分析优先保护区内受威胁动物的保护现状。研究发现,29个50km×50km的网格单元就包含了全部的受威胁陆栖哺乳物种,其中位于喜马拉雅山东南区等地的10个网格区域覆盖有80%以上的物种,其所处的10组县级行政区内被主要自然保护地保护的土地面积占25.9%,物种数占83.6%,存在一定的保护空缺。本文采用Dobson排除算法,以小面积规则网格为基本单元,顾及到了实验结果的客观性,有助于提高优先保护区的识别效率。  相似文献   

12.
邹武  王渌  赖童  朱祥福  陈伏生  曾菊平 《生态学报》2022,42(5):1889-1900
生境保护是维持生物多样性的基本途径,南方山地阔叶林维系着当地的生物多样性热点,而由于保护覆盖不足,保护效果亟待提高。以典型山地阔叶林树种木莲(Manglietia fordiana)为例,通过大尺度采集发生点,预测适生分布,获知影响其适生分布的关键因子。同时,以九连山种群进行案例研究,调查地方尺度下木莲植株的发生,了解其在山地地形、植被类型的选择特征。用MaxEnt构建最佳模型预测适生区,结果显示木莲适生区主体位于中国南部、西南部山地(如戴云山、南岭、罗霄山、武夷山等),向北延至大别山南坡,向西达横断山脉。木莲适生分布主要受最干月降水量(bio14,贡献率34.6%)、海拔高度(19.2%)、温度季节性变化标准差(bio4,15.6%)、最暖季降水量(bio18,12.0%)、最冷月最低温度(bio6,7.0%)影响,其60%适生概率范围或生态位bio14为30-55mm、海拔为400-1500m、bio18为500-800mm等。在适生区基础上,叠加考虑阔叶林分布,并选择其偏好海拔高度(>700m)提取获得木莲优先保护区,经与现有自然保护区叠加分析后,进行空缺识别,结果显示优先区保护覆盖为4.1%-6.0%,而高适生区保护覆盖也<10%(占比8.03%),覆盖比重较低。而沿<400m、400-700m、>700m海拔梯度显示>700m区域保护比重(8.7%)明显高于400-700m (4.4%)与<400(2.3%)组,说明前期保护区设计基本遵从优先区保护原则,能有效保护木莲高适生区。同样的,九连山保护区案例显示,当地木莲51.4%高适宜生境受到核心区的严格保护。研究结果表明,仍需在黄山-天目山区、苗岭东段、高黎贡山北段与南段、中越边界山区与广东西南山区6个空缺提高保护覆盖,通过建立新的自然保护区,优化当前保护网络,提高山地阔叶林的整体保护水平。  相似文献   

13.
The addition of species to the European butterfly list since 1983 has resulted in a number of highly significant changes. Most important are the increases in the number and proportion of endemics and of rare species, and a regional excess of species and endemics for southern Europe compared to northern Europe. There is also a surplus of Lycaenidae and Satyridae compared to other families, and an increase in species per genus associated with the reduction in genera. These additions raise two issues. First, the potential conservation load for European butterflies is inflated at species level. This is especially the case for southern Europe, which has disproportionate increases in rare and endemic species, more particularly if rarity and endemism are found to equate with threat of extinction. Second, the inflation in rarity and endemism suggests that there is a trend to promote ever more local populations (races, subspecies) to species. The taxonomic status of species being added to the list, a quarter of which are regarded as doubtful, is increasingly difficult to determine. Consequently, there is a danger that this may call into question the validity and objectivity of taxonomic practices, and of databases dependent on them, used by conservation. Revision of higher and lower butterfly taxa is urgently required.  相似文献   

14.
Aim Most approaches to conservation prioritization are focused on biodiversity features that are already threatened. While this is necessary in the face of accelerating anthropogenic threats, there have been calls to conserve large intact landscapes, often termed ‘wilderness’, to ensure the long‐term persistence of biodiversity. In this study, we examine the consequences of directing conservation expenditure using a threat‐based framework for wilderness conservation. Location The Australian continent. Methods We measured the degree of congruence between the extent of wilderness and the Australian protected area network in 2000 and 2006, which was established using a threat‐based systematic planning framework. We also assessed priority areas for future reserve acquisitions identified by the Australian government under the current framework. Results In 2000, 14% of Australia’s wilderness was under formal protection, while the protected area network covered only 8.5% of the continent, suggesting a historical bias towards wilderness protection. However, the expansion of the reserve system from 2000 to 2006 was biased towards non‐wilderness areas. Moreover, 90% of the wilderness that was protected over this period comprised areas not primarily designated for biodiversity conservation. We found a significant (P < 0.05) negative relationship between bioregions considered to be a priority for future reserve prioritization and the amount of wilderness they contain. Main conclusions While there is an urgent need to overcome past biases in reserve network design so as to better protect poorly represented species and habitats, prioritization approaches should not become so reactive as to ignore the role that large, intact landscapes play in conserving biodiversity, especially in a time of human‐induced climate change. This can be achieved by using current or future threats rather than past threats to prioritize areas, and by incorporating key ecological processes and costs of acquisition and management within the planning framework.  相似文献   

15.
16.
Coastal-marine biodiversity conservation must focus increasingly at the level of the land- and seascape. Five cases illustrate discontinuities and synergisms and how system changes may take place. For Caribbean coral reefs, the result of overfishing and disease has been a shrinkage in the entire system, the effects of which may cascade through the coastal seascape. For Beringia, patterns of benthic diversity are best understood in a manner that matches the multiscale, integrated dynamics of weather, ice, marine mammal feeding, and community structure. In the case of US East Coast estuaries, oyster reefs may be keystone elements, with important effects on functional diversity. Large-scale coastal systems depend upon the connectivity of fresh and marine waters in the coastal zone, having implications for the apparent stochasticity of coastal fisheries. And, for a coastal barrier-lagoon site, a state change may be described in terms of a combination of succession, the attainment of a quasi-equilibrium state, and disturbance. A profound problem for conservation is that there is very little information about the relationship between species diversity and ecological function. Coastal-marine biodiversity conservation is best addressed at the level of the land- and seascape.  相似文献   

17.
水獭是水生生态系统重要的指示种和旗舰种, 由于强烈的人为干扰, 中国的水獭种群数量大幅下降, 部分区域已局部灭绝。然而目前国内对水獭的调查和研究非常有限, 本底不清的状况已经严重影响到水獭的野外保育工作。本文以东北地区的欧亚水獭指名亚种(Lutra lutra lutra)为研究对象, 基于2016-2020年的调查数据, 使用组合建模的方法评估了水獭的潜在分布区; 利用地理信息系统和系统保护规划软件分析了水獭的保护优先区并计算了各省级行政区内水獭潜在分布区和保护优先区面临的人类压力; 结合国家级自然保护区的空间布局分析了水獭的保护现状, 并以内蒙古森工集团、大兴安岭林业集团、伊春森工集团三大国有林区为例分析了重点国有林区在水獭保护中的作用。结果表明: (1)水獭潜在分布区和保护优先区面积分别为104,515.04 km2和45,448.99 km2, 其中大兴安岭的水獭保护优先区集中连片, 并与小兴安岭的保护优先区相连, 栖息地之间没有明显地理隔离, 是维持东北地区水獭种群稳定的重中之重; (2)水獭面临的人类压力大小依次为: 辽宁 > 吉林 > 黑龙江 > 内蒙古; (3)研究区内110个国家级自然保护区中有63个包含水獭潜在分布区, 覆盖面积为12,168.93 km2, 仅占水獭潜在分布区面积的11.64%, 其中32个国家级自然保护区包含水獭保护优先区, 占水獭保护优先区面积的10.88%; (4)三大国有林区涵盖了71.18%的水獭潜在分布区和79.26%的保护优先区(面积分别为74,390.89 km2和36,022.22 km2)。由此可见, 尽管水獭潜在分布区中国家级自然保护区占比较低, 但是在天然林全面禁伐的背景下, 重点国有林区可能在未来东北地区的生物多样性保护中发挥更大作用, 因此我们建议将重点国有林区中具有重要保护价值的区域逐步纳入以国家公园为主体的自然保护地体系中, 以实现生物多样性的系统性和完整性保护。最后, 本文结合研究结果和实地调研提出以下保护建议: (1)加强对河流污染物的管理; (2)控制渔民捕鱼强度; (3)开展全面的水獭专项调查并建立长期的监测体系; (4)加大对水獭的科研投入; (5)加强宣传力度, 提升公众保护意识。  相似文献   

18.
生物多样性和生态系统服务的保护与可持续管理是当今世界面临的重大挑战之一,但如何判识与优化集成生态系统服务与生物多样性保护对象的保护优先区网络,相关研究还很有限。针对“三江并流”区,选取珍稀濒危与特有动植物物种和自然植被类型作为生物多样性保护对象,以调节服务(碳存储、固碳和土壤保持)、文化服务(自然游憩)和供给服务(水源供给)为生态系统服务保护对象。应用系统保护规划方法,首先判识出单一生物多样性和生态系统服务保护优先区;然后,分析这些保护优先区间的相关关系,并选择与生物多样性正相关的生态系统服务类型,判识集成生态系统服务与生物多样性的保护优先区;最后,评估了集成生态系统服务与生物多样性保护优先区在六类已建保护地中的保护状况。结果表明:(1)“三江并流”区多情景规划得到的生物多样性与生态系统服务保护优先区之间均呈正相关关系;(2)与分别针对生态系统服务和生物多样性的规划情景相比,集成生态系统服务与生物多样性保护优先区能够同时对两类保护对象提供最高的保护覆盖率;(3)集成生态系统服务和生物多样性保护优先区占研究区总面积的48.9%,其已建保护地覆盖率为32.5%,说明现有保护地体系仍存在保护...  相似文献   

19.
A medicinal plant study was carried out in eighteen parishes and 54 villages of Erute county, Lira district, Uganda. Parishes and villages were selected using stratified random sampling techniques. Questionnaires, interviews and discussions with the local people were used to obtain information on the names of the plants, their medicinal uses and conservation methods. The number of the medicinal plants species used was 180 belonging to 144 genera and 57 families of flowering plants. The major families recorded for medicinal purpose included Fabaceae (37 species), Asteraceae (26 species), Euphorbiaceae (eleven species), Vitaceae (eight species), Verbenaceae (seven species), Poaceae (six species), Solanaceae (five species), and Rubiaceae (four species). There is a need for putting in place measures to conserve these plants. Unfortunately, most of the healers or users were not interested in cultivation of the plants. The situation could worsen with the social changes and demand for land for agriculture in the district.  相似文献   

20.

Aim

Biodiversity hotspots often span international borders, thus conservation efforts must as well. China is one of the most biodiverse countries and the length of its international land borders is the longest in the world; thus, there is a strong need for transboundary conservation. We identify China's transboundary conservation hotspots and analyse the potential effects of the Belt and Road Initiative (BRI) on them to provide recommendations for conservation actions.

Location

China, Asia.

Methods

We compiled a species list of terrestrial vertebrates that span China's borders. Using their distribution, we extracted the top 30% of the area with the highest richness value weighted by Red List category and considered these transboundary hotspots for conservation priority. Then we analysed protected area (PA) coverage and connectivity to identify conservation gaps. To measure potential impact of the BRI, we counted the species whose distribution range is traversed by the BRI, and calculated the aggregation index, proportion of natural land and night light index along its routes.

Results

We identified 1964 terrestrial vertebrate species living in the border region. We identified four transboundary hotspots and found insufficient PA coverage and low connectivity in three of them. The BRI routes intersected all four hotspots and traversed 82.4% (1619/1964) of the transboundary species, half of which (918) are sensitive to the potential risks brought by the BRI. Night light index increased generally along the BRI. However, the proportion of natural land and the aggregation index near the BRI showed different trends in hotspots.

Main Conclusions

There is an urgent need for conservation action in China's transboundary region. The BRI should put biodiversity conservation at the core of its development strategy. Furthermore, we suggest using the planned BRI as a platform for dialogue and consultation, knowledge and data sharing, and joint planning to promote transboundary conservation.  相似文献   

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