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1.
This study documents the distribution patterns, endemism and uniqueness (species richness) of fishes in the Tunga and Bhadra rivers of Western Ghats, India. We recorded 77 species represented by 7 orders, 16 families and 44 genera, of which 36 species are endemic to Western Ghats, 12 species endemic to India and 26 species endemic to the Indian Subcontinent. Based on our analysis on the distribution patterns, the Tunga River is richer in diversity and higher in endemism than the Bhadra. We calculated the similarity of the species composition among sites within these two rivers using the Jacquard index. The similarity index between the sampling sites of these rivers revealed that the similarity decreases with increasing distance between the sampling sites. Of the 77 fish species we collected, 8 species (11.1%) are in the Critical category, 10 species (13.8%) are in the High Risk category, 36 species (50%) are in the Moderate category and the remaining 18 species (25%) are at lower risk. The threat status of fishes found in the Tunga and Bhadra rivers strongly suggests the need for effective conservation measures to conserve the fish species richness of these rivers.  相似文献   

2.
为了评估中国爬行动物红色名录, 我们按照爬行动物生物学特性, 适当修改了IUCN濒危物种红色名录标准Version 3.1。在此基础上, 评估了中国爬行动物生存现状, 参与编制了《中国生物多样性红色名录——脊椎动物卷》。此次评估的中国爬行动物有3目32科133属461种, 结果为: 区域灭绝(RE) 2种、极危(CR) 34种、濒危(EN) 37种、易危(VU) 66种、近危(NT) 78种、无危(LC) 175种以及数据缺乏(DD) 69种。中国受威胁(包括极危、濒危、易危)的爬行动物共计137种, 约占总数的29.72%, 包括龟鳖目31种、有鳞目蛇亚目67种、蜥蜴亚目38种和鳄形目1种, 高于2014年《IUCN濒危物种红色名录》评估的世界爬行动物受威胁比例(13.61%)。在所有受威胁物种中, 受威胁比例最高的类群是鳄形目(100%)和龟鳖目(91.18%), 其次是有鳞目蛇亚目(28.39%), 第三是有鳞目蜥蜴亚目(20.21%)。中国爬行动物特有种受威胁物种有39种, 占特有种总数(143种)的27.27%, 占受威胁物种总数(137)的28.47%。长江以南的华南和西南地区受威胁的物种最多。爬行动物受人类干扰严重, 主要表现为: 栖息地质量退化及生境破碎化、过度利用及污染和气候变化等。尽管自1989年《中华人民共和国野生动物保护法》实施以来, 一些中国濒危爬行动物的生存状况得到改善。但鉴于中国爬行动物区系的独特性和多样性、地形地貌的复杂性及社会经济发展的不均衡性, 为了维持区域生态安全和资源可持续利用, 拯救中国濒危爬行动物, 尤其是中国特有爬行动物中的极危物种, 是中国动物保护工作最迫切的任务之一。  相似文献   

3.
4.
中国首批濒危苔藓植物红色名录简报   总被引:8,自引:0,他引:8  
初步报道了2004年上海中国苔藓植物多样性保护国际研讨会上通过的中国首批濒危苔藓植物红色名录。名录共计82种,其中藓类植物28科、47属、50种,苔类植物12科、26属、31种和角苔类植物1科、1属、1种。根据修订的IUCN/IAB标准, 82种苔藓植物中,36种划为极危(CR),29种划为濒危(EN),17种划为易危(VU)。对中国首批濒危苔藓植物的地理分布特点、濒危原因及今后的保护行动也进行了初步讨论。  相似文献   

5.
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   

6.
The bryophyte Red List of Serbia and Montenegro comprises 254 species (212 mosses and 42 liverworts). Serbia and Montenegro have 39.50% of threatened bryoflora. One moss species is considered as extinct (Encalypta serbica Katic). In the threatened categories there are 20 critically endangered (CR), 35 endangered (EN) and 100 vulnerable (VU) bryophyte species. Seventy-two species are considered to be of low risk, and 36 are too data deficient to place them in any category, but potentially with further investigation will enter one of the threat categories in the Red List.  相似文献   

7.
评世界保护联盟新的物种受威胁分类系统草案   总被引:2,自引:0,他引:2  
为了进一步了解物种受威胁的情况和发展,以加强物种保护工作,世界保护联盟制定了一个新的物种受威胁分类系统草案,把物种受威胁的程度分为9个级别,即绝灭种、野生状态下的绝灭种、极危种、濒危种、渐危种、敏感种、安全的/危险性小的种、不充分了解的种和未估价的种。本文对这个分类系统草案作了简略的评介。  相似文献   

8.
The mountainous Western Ghats are part of a biodiversity hotspot and extend for about 1600 km, lying close and subparallel to the west coast of peninsular India. The region is a centre of diversity for amphibians, and recent preliminary work on some components of both caecilian (Gymnophiona) and frog (Anura) fauna is indicative of a high degree of local endemism. We investigated diversity in mitochondrial rRNA 12S and 16S sequences for long-tailed, unstriped Ichthyophis (Amphibia: Gymnophiona: Ichthyophiidae) that potentially represent four taxonomically confused and poorly known endemic caecilian species. Data were analysed for18 individuals from along c . 1500 km of the Western Ghats region. Genetic diversity is remarkably low, with a maximum uncorrected p -distance of 0.5%. These DNA sequences and new morphological data do not allow us to reject the null hypothesis that the sample comprises only a single, widely distributed, highly interconnected species. The phylogenetic signal among the data is extremely low. However, population genetic analyses reveal that the Palghat Gap, a c . 30 km discontinuity in the Western Ghats considered to be significant in the biogeography of other organisms occurring in this region, corresponds to a significant subdivision of long-tailed, unstriped Ichthyophis into two groups.  相似文献   

9.
以《中国珍稀濒危保护植物名录》、《中国植物红皮书》、《国家重点保护野生植物名录(第一批)》、《中国物种红色名录》、《中国生物多样性红色名录(高等植物卷)》、《内蒙古珍稀濒危保护植物名录》和《内蒙古珍稀濒危植物图谱》中127种内蒙古珍稀濒危植物为研究对象,通过资料收集及专家咨询,构建了内蒙古珍稀濒危植物受威胁等级、优先保护评估体系.建立了濒危系数、遗传价值系数、利用价值系数、生境系数、繁殖系数5项准则,准则下共设17个指标;运用层次分析法确定指标体系权重,计算出珍稀濒危植物濒危等级及优先保护级别.结果表明: 极危种2种、濒危种13种、易危种37种、近危种44种、无危种31种,分别占总数的1.6%、10.2%、29.1%、34.7%、24.4%.其中,受威胁种(极危、濒危和易危种)共52种,占总种数的40.9%.一级保护植物35种、二级保护植物72种、三级保护植物20种,分别占总数的27.6%、56.7%、15.8%.本评估结果与《中国生物多样性红色名录(高等植物卷)》、《内蒙古珍稀濒危保护植物名录》相比,有75种植物的濒危等级和62种植物的保护级别发生了变化.其中新增了9种植物的濒危等级评估和32种植物的保护级别.  相似文献   

10.
在对有关模式标本资料广泛查询的基础上,统计出以梵净山国家级自然保护区为模式产地的维管植物91种(含种下单位),隶属于47科73属。除1种无采集人信息外,其余90种由31人或团队采集,这些标本保存于国内外21个研究机构。以该地为模式产地的物种中,19种以梵净山命名。原学名中有17个被归并,其中12个学名在种级水平发生了变化,5个学名在种下水平发生了变化。以该地为模式产地的物种中受威胁的共15种,包括极危(CR) 1种,濒危(EN) 6种,易危(VU) 8种。  相似文献   

11.
刘艳  杨钰爽 《生物多样性》2019,27(6):677-274
生物多样性保护优先区的生物多样性十分丰富, 对于生物多样性保护具有重要意义。本文基于野外调查数据和文献资料, 整合大巴山和武陵山两个中国生物多样性保护优先区重庆境内的苔藓植物名录, 通过分析物种丰富度、中国特有种和受威胁物种, 比较了这两个地区的苔藓植物组成特点和相似性。结果显示, 两个保护优先区重庆境内共有苔藓植物77科221属722种, 其物种数分别占重庆市和中国苔藓植物总种数的76.0%和23.9%。两个区域分布有中国特有苔藓植物56种, 占中国苔藓植物总种数的1.9%; 分布有极危苔藓植物1种、濒危4种和易危3种。科、属、种的Jaccard相似性系数分别为0.7、0.6和0.3, 表明两个区域物种组成差异较大。大巴山和武陵山两个中国生物多样性保护优先区都具有较高的苔藓植物物种多样性, 其种类组成具有一定代表性, 对重庆市和中国苔藓植物多样性保护具有重要价值。  相似文献   

12.
The Kimberley region of Western Australia possesses a poorly studied freshwater fish fauna with high endemism in an aquatic landscape subject to monsoonal floods and dry season isolation. In the first population genetic study of freshwater fish in this region, the authors tested the effects of geographic barriers on genetic structure at multiple spatial scales in east Kimberley populations of the western rainbowfish, Melanotaenia australis , the most widespread and abundant species in the region. Based on allozyme comparisons, hierarchical analysis of F ST revealed increasing genetic subdivision with spatial scale. Minimal genetic structure within creeklines demonstrated that wet season dispersal, rather than dry season isolation, determines genetic structure at small scales. At the scale of sub-catchments, a pattern of isolation by distance along creeklines was evident. Genetic subdivision between adjacent river systems was greater between rivers separated by a plateau than by lowlands. This implies greater connectivity of populations in lowland areas and may explain the greater similarity of the east Kimberly freshwater fish fauna with lowlands to the east than with the more rugged regions to the west. Similarly, greater connectivity between lowland populations may account for the on-average larger distribution of lowland Melanotaeniids.  相似文献   

13.
Aim  To provide an objective geographic framework displaying the distribution patterns of freshwater fishes from Argentina.
Location  Argentina, southern South America.
Methods  Parsimony analysis of endemicity (PAE) and similarity and cluster analyses were applied to presence and absence data on 440 fish species from 52 localities in Argentina. Both 50% majority consensus and strict consensus analyses were undertaken in the first case, and the Jaccard similarity index was used in the second.
Results  Five ichthyogeographic provinces are described based on a PAE of the 52 localities. A cluster analysis provided similar results.
Main conclusions  The following zoogeographic provinces are proposed for Argentine freshwater fish fauna following the International Code of Area Nomenclature: Andean Cuyan, Patagonian, Aymaran, Great Rivers and Pampean. The former two are placed within the Andean Subregion of the Austral Region, and the latter three within the Neotropical Subregion of the Holotropical Region. These provinces, based on results coinciding with PAE and cluster analysis, represent the first classification of Argentine provinces based on objective methods. Some small regions of endemism and some localities remain separated from the proposed regions. The new scheme includes valuable empirical information from previous schemes, and is in agreement with ecological zones and other environmental arrangements proposed earlier.  相似文献   

14.
Seventy one fish species belonging to 27 families and 50 genera were collected from various sampling sites spread along the upstream and downstream parts of the Chalakudy river, in the Western Ghats biodiversity hotspot in Kerala, South India. Cyprinids were the most dominant group represented by 24 species belonging to 13 genera, followed by the catfishes of the family Bagridae (7 species from 2 genera) and loaches belonging to the family Balitoridae (5 species from 5 genera). Of the 71 species, 4 belong to the ‘critically endangered’ (CR) and 16 to the ‘endangered’ (EN) category. 3 of the critically endangered species are strictly endemic to the Chalakudy river system. We also collected 5 exotic species several of them categorized as potential pest. Fish species richness (FSR) showed a direct relationship with increasing stream order with maximum values observed in the downstream/low elevation regions. Considerable differences were observed in the FSR between different microhabitats with maximum values observed in bed rock and pool riffle and the lowest in regimes followed by step pools. Diversity and species richness decreased with increasing altitude and higher diversity and species richness were observed in sampling sites located between 0–200 m above sea level. A definite temporal partitioning was also observed with regard to FSR with higher richness during the day time and the lowest observed at dawn. Indiscriminate collection of endemic and threatened ornamental fish species for export, exploitation of endangered food fishes by forest-dwelling communities and local fisher folk, pollution, loss of riparian cover, damming and exotic species threaten the rich ichthyofaunal diversity of Chalakudy River. An urgent need exists for studying the life history traits and demography of the most important endemic and threatened fishes, as lack of information on these aspects have significantly affected conservation efforts. The implementation of strong management strategies like fixing total allowable catch (TAC), and the use of quotas are needed to reduce the overall collection pressure with regard to the trade in native ornamental species from the river.  相似文献   

15.
Río Champotón in the Yucatán Peninsula is within the Usumacinta Province, the most diverse in fish fauna in Mexico, and is part of the Mesoamerican hotspot, with high endemism and exceptional habitat loss. The spatial and seasonal variability of its fish fauna and their relation to physical habitat characteristics were studied, finding 53 taxa. Canonical correspondence analysis shows salinity, distance from the river mouth, and substratum type differentiate an estuarine and a freshwater region. Fish fauna replacement was observed, with taxa exclusive to each region: 26 estuarine and 27 freshwater species. Six freshwater species enter the estuarine region when the high river flow depletes salinity. Estuary showed greater seasonal differences in specific richness than the freshwater region, which have sites with higher local specific richness. Despite its small drainage, Río Champotón has a highly diverse fish fauna and some areas are affected by human activity and the hurricane season. Its conservation is of critical importance.  相似文献   

16.
Distribution of the freshwater fishes of Japan: an historical overview   总被引:2,自引:0,他引:2  
Japanese freshwater fishes, including lampreys, comprise 15 orders, 35 families, and 96 genera, with 211 species and subspecies. Most belong to the families Cyprinidae (29% of species and subspecies), Gobiidae (21%), Salmonidae (10%), and Cobitidae (8%). Cyprinids and cobitids presumably originated from east Asia, gobiids from southeast Asia, and cottids and salmonids from the north Pacific. Japanese freshwater fishes include 88 endemic species and subspecies, of which three have been extirpated. Fishes introduced into natural rivers and lakes for inland commercial fisheries and sport fishing, and by accident, include many exotic species, of which 23 now inhabit natural freshwaters. These often have destroyed the local fish fauna by predation, and caused genetic pollution by hybridization with local strains. Destruction of freshwater environments by land development also poses a threat to Japanese freshwater fish communities. In addition Japanese freshwater systems have been markedly altered by development of rice paddy fields which have caused some species to decline but others to flourish, and changed the distribution patterns of fishes between upstream and downstream areas. To conserve endangered species and declining communities of Japanese freshwater fishes, we need to clarify the characteristics of their original habitats and the effects of developing paddy fields, from both the ecological and historical points of view.  相似文献   

17.
Theaceae, an economically important angiosperm family, is widely distributed in tropical and subtropical forests in Asia. In China, Theaceae has particularly high abundances and endemism, comprising ~75% of the total genera and ~46% of the total species worldwide. Therefore, predicting the response of Theaceae species to climate change is vital. In this study, we collected distribution data for 200 wild Theaceae species in China, and predicted their distribution patterns under current and future climactic conditions by species distribution modeling (SDM). We revealed that Theaceae species richness is highest in southeastern China and on Hainan Island, reaching its highest value (137 species) in Fujian Province. According to the IUCN Red List criteria for assessing species threat levels under two dispersal assumptions (no dispersal and full dispersal), we evaluated the conservation status of all Theaceae species by calculating loss of suitable habitat under future climate scenarios. We predicted that nine additional species will become threatened due to climate change in the future; one species will be classified as critically endangered (CR), two as endangered (EN), and six as vulnerable (VU). Given their extinction risks associated with climate change, we recommended that these species be added to the Red List. Our investigation of migration patterns revealed regional differences in the number of emigrant, immigrant, and persistent species, indicating the need for targeted conservation strategies. Regions containing numerous emigrants are concentrated in Northern Taiwan and coastal regions of Zhejiang and Fujian provinces, while regions containing numerous immigrants include central Sichuan Province, the southeastern Tibet Autonomous Region, southwest Yunnan Province, northwest Sichuan Province, and the junction of Guangxi and Hunan provinces. Lastly, regions containing persistent species are widely distributed in southern China. Importantly, regions with high species turnover are located on the northern border of the entire Theaceae species distribution ranges owing to upwards migration; these regions are considered most sensitive to climate change and conservation planning should therefore be prioritized here. This study will contribute valuable information for reducing the negative impacts of climate change on Theaceae species, which will ultimately improve biodiversity conservation efficiency.  相似文献   

18.
Decline in the populations of bumble bees and other pollinators stress the need for more knowledge about their conservation status. Only one of the 25 bumble bee species present in Hungary is included in the Hungarian Red List. We estimated the endangerment of the Hungarian bumble bee (Bombus Latr.) species using the available occurrence data from the last 50 years of the 20th century. Four of the 25 species were data deficient or extinct from Hungary. About 60% of species were considered rare or moderately rare. Changes in distribution and occurrence frequency indicated that 10 of the 21 native species showed a declining trend, while only three species increased in frequency of occurrence. According to the IUCN Red List categories, seven species (33% of the native fauna) should be labelled as critically endangered (CR) and 3 (14%) as endangered (EN). Our results stress an urgent need of protection plans for bumble bees in Hungary, and further underlines the validity of concern over bumble bees all over Europe.  相似文献   

19.
The remote and sparsely populated Kimberley region is a major centre of endemism in the Australian monsoonal tropics that is threatened by uncontrolled fire following the disruption of Aboriginal burning practices. A recent study of the ant fauna of the Mitchell Falls area of the northern Kimberley revealed that 44 % of the species are known only from the Kimberley region. The fauna appeared to be highly resilient in relation to fire. Levels of endemism in the Mitchell Falls region are likely to be particularly high because it occurs in a high rainfall zone (>1,200 mm per year) that is isolated from similar zones elsewhere in northern Australia. In contrast, the lower rainfall eastern and southern Kimberley form part of continuous climatic bands that extend right across northern Australia, and so species from these areas might be expected to be more widely distributed. Here we describe the ant fauna of Mirima National Park in the eastern Kimberley, in the context of a broader biogeographic analysis of the Kimberley ant fauna and an understanding of its response to wildfire. We specifically test two hypotheses: first, that the ant species of Mirima tend to be more widely distributed across northern Australia than those of Mitchell Falls; and, second, that Mirima ant communities are highly resilient in relation to fire, as revealed by a weak relationship with time-since-fire. Analysis of distributional ranges revealed that 24 % of Mirima ant species are known only from the Kimberley, which, as hypothesized, is substantially lower than at Mitchell Falls (44 %). Also as we hypothesized, the Mirima ant fauna shows little relationship with time since fire, with no systematic variation in ant species richness between sites with 1–4 years since fire, and no relationship between time since fire and site similarity based on overall ant species composition. Although our study indicates that levels of endemism in the ant fauna of the eastern Kimberley are lower than those in the northern Kimberley, they are still extremely high. It seems that at least a quarter of all Kimberley ant species are endemic to the region. This confirms the Kimberley as a highly significant region for ant biodiversity. We have also shown that the regional ant fauna is highly resilient in relation to the key threatening process in the region.  相似文献   

20.
Freshwater fishes are an important but relatively little known component of the highly diverse fish fauna of Micronesia. Localities supporting communities of freshwater fishes include large high islands, with considerable habitat complexity, and smaller low islands, such as atolls and raised coral islands, with limited freshwater habitat. Both types of islands may support species with adult life history styles that are (a) amphidromous and catadromous, (b) euryhaline (often estuarine), or (c) marine species which enter freshwater from time to time. We compared patterns of species richness and similarity between Micronesian localities for amphidromous and catadromous, euryhaline and marine species (ACEM) pooled, and for amphidromous and catadromous species (ACFW). Species richness of both ACEM and ACFW fishes was greatest on larger high islands compared to smaller high and all low islands. Cluster analysis of similarity indices for ACEM species between localities revealed two faunal components: high islands and low islands. High islands were further partitioned into a Caroline Islands cluster and a separate Mariana Islands cluster. Cluster analysis of ACFW species was more complex. One cluster consisted of a low island and a small high island, both in the Carolines chain and with limited freshwater habitat. The second cluster was partitioned into high islands and low islands that reflected influences of both size and geographical location.  相似文献   

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