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千岛湖岛屿小型兽类群落的多样性 总被引:2,自引:1,他引:2
2007 年秋季和2008 年春季,选取千岛湖地区14 个岛屿和2 个半岛作为样地,采用夹夜法进行小型兽类群落组成调查。两季度共布夹20 400 个,捕获小型兽类1 141 只,隶属2 目3 科9 属13 种,啮齿目(Rodentia)鼠科(Muridae)10 种和仓鼠科(Cricetidae)1 种,食虫目(Insectivora)鼩鼱科(Soricidae)2 种。利用以上结果分析其群落多样性,结果显示:14 个岛屿小型兽类群落春、秋两季的多样性指数、均匀度指数和优势度指数均呈现极显著差异且优势种发生变化;对可能影响岛屿小型兽类群落多样性的岛屿面积、距最近陆地距离、距最近大岛距离和植物丰富度等因素进行逐步回归分析,发现只有植物丰富度对小型兽类群落的物种丰富度有显著影响;对16 个样地按照物种组成比进行聚类,许源半岛样地与14 个岛屿聚为一类,姚家半岛样地单独归为一类,相似性指数比较结果亦显示姚家半岛样地与其它样地的相似性指数偏低。结论:景观破碎化导致千岛湖岛屿小型兽类群落的稳定性下降,物种多样性季节变化强烈;随岛屿面积的增加,小型兽类物种丰富度并非总是增加的,而是出现反复,呈现明显的小岛效应;14 个岛屿的物种与许源半岛样地物种构成比接近,推断在水库未形成前属同一生境。 相似文献
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2007年秋季和2008年春季,采用夹夜法对千岛湖14个岛屿进行小型兽类群落组成调查,研究其群落空间分布格局及其影响因素。两季度共布置夹16 800只,捕获小型兽类1 037只,隶属2目2科7属11种。其中啮齿目(Rodenria)鼠科(Muridae)9种,食虫目(Insectivora)鼩鼱科(Soricdae)2种。结果显示:千岛湖小型兽类群落呈非随机分布格局;嵌套分析表明,千岛湖岛屿小型兽类群落呈现极显著嵌套格局,植物丰富度和生境专属性两项参数对其嵌套格局的形成具有显著影响,从而使适应力强的物种能够在多样的环境中生存,而适应力弱的物种则局限在特定的环境中。由于取样强度差异会过高地估计嵌套程度,故在研究中应尽量去除取样强度的干扰。 相似文献
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岛屿群落由于受岛屿栖息地特征结构的影响而产生一系列特殊的格局。通过对杭州市园林鸟类群落的研究,分析了园林鸟类群落的物种数、组成和多度与园林岛屿性状的关系,从而确定了园林鸟类群落存在如下与园林的岛屿性状有关的格局:(1)在物种数方面,在相同的取样面积下,园林的物种数随园林面积的增大而减少;(2 )在群落组成上,园林鸟类群落呈现出不完全的嵌套格局,分布于物种数较少的园林中的物种多数也分布在物种数较多的园林中;(3)在物种多度方面,园林鸟类的总密度随面积的增大而减少,园林鸟类多度的均匀度随着面积的增大而提高。群落的岛屿性格局反映了栖息地的岛屿化对群落的影响,总称之为群落的岛屿效应。通过比较全年、繁殖季节、越冬季节和迁徙季节群落岛屿性格局的显著性,分析群落的稳定性与群落岛屿效应之间的关系,认为两者之间没有必然的联系,相对非稳定的群落也可导致显著岛屿效应 相似文献
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唐家1989 年4~11 月对唐家河自然保护区的小型兽类进行了研究, 共布放11 000多铗日, 捕获小型兽类846 只。共有小型兽类21 种, 划分为4 个群落。利用方差分析和多重比较分析出了各群落内的优势种, 并比较了方差分析与以捕获比例确定小型兽类群落优势种的差异。根据香农- 威纳公式分析了群落的多样性和均匀性, 发现随着群落内物种数的增加, 群落的多样性和均匀性指数也都增加, 但是随着群落内优势种所占比例增加, 群落的多样性则显著降低, 均匀度也降低。 相似文献
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1992-05-08、1993-06-07和1994-06-07分别在喜马拉雅山南坡,西藏亚东县、错那县和隆子县捕获小型兽类,采集蚤类标本,共获蚤1805只;经鉴定它们隶属于4科22属46种。以该地区小型兽关作为研究对象,计算其染蚤指数和蚤类群落相似性指标,并对宿主动物体外寄生蚤群落进行主成分分析。结果表明:宿主动物的生境对其体外寄生蚤群落相似起决定作用,而宿主动物的分类地位亦有一定的影响。 相似文献
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1997年1月至1997年12月间,以杭州市的园林鸟类群落为研究对象,对岛屿栖息地鸟类群落的丰富度与面积,人为干扰,内部结构和周围景观结构等多种因素的关系进行了系统的分析和检验。在杭州市各园林中共观察到82种鸟类。园林单次调查的鸟类物种数(S)与园林全年总物种数(Sy)与园林面积(A)的最佳回归拟合方程分别为;S= 2.7432A^0.3846,Sy=10.6574A^0.3669。杭州市园林鸟类群落物种-面积关系的成因不支持平衡假说,随机取样假说,栖息地多样性假说和干扰假说,岛屿栖息地鸟类群落的丰富度是多因素综合作用的结果,包括取样面积效应(排除了取样面积效应之后,小园林具有更高的物种密度),栖息地结构的多样性(其中树种多样性是最主要的影响因子),干扰因素,物种因素和研究尺度等几个方面。 相似文献
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R. J. Berry 《Biological journal of the Linnean Society. Linnean Society of London》1986,28(1-2):205-230
Island populations are of interest for their differentiation as well as their species diversity; some of the earliest biological interest in islands was concerned with the number of 'endemics' thereon. There is dispute about the long-term evolutionary importance of island forms, but they are rich sources of data for studying the under-exploited interface of genetics, ecology and physiology. Differentiation of island populations may arise from genetic change after isolation, or from the chance collection of alleles carried by the colonizing group itself. The general reduction of genetic variance in island populations compared to continental forms of the same species suggests that founder events have played a major role in the formation of most island forms. However, there is ample evidence of adaptation in island populations despite this lower variation; this is relevant when using island biology as a base for the deriving of rules for genetic conservation. 相似文献
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西沙群岛植物资源调查 总被引:11,自引:0,他引:11
西沙群岛主要的植被类型是常绿珊瑚岛林、灌木林或滨海植被。本区有植物89科224属340种,其中大型真菌6科11属22种,地衣1种,蕨类4科4属5种,被子植物78科208属312种。根据其经济用途,划分为10个类型,主要资源植物有药用植物、蜜源植物、食用植物、观赏植物等。西沙群岛的植物区系与海南岛十分相似,属、种的相似性指标分别为98.46%和94.09%。泛热带分布的属是本区系中最大的部分,占总属数的70.00%。最后对西沙群岛植物资源的保护和利用进行了讨论。 相似文献
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Fourteen species of saprotrophic fungi isolated from various substrates from Xisha Islands are reported, including a new record species-Curvlaria tuberculata Jain. The others are: Alternaria alternata (Fr.) Keissler. A. phragmospora van. Emden, Aspergillus niger van. Tiegh., Cladosporium arysporum Berk. & Curt., C sphaerospormum Penz., Curvularia affinis Boedijn, C. geniculata (Tracy & Earle) Boedijn, C. lunata (Walk.) Boedijn, Exserohilium turcicum (Pass.) Leonard & Suggs.,Humicola grisea Traaen, Botryodip… 相似文献
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Yadeh E. Sawyer Stephen O. MacDonald Enrique P. Lessa Joseph A. Cook 《Ecology and evolution》2019,9(4):1777-1797
Although islands are of long‐standing interest to biologists, only a handful of studies have investigated the role of climatic history in shaping evolutionary diversification in high‐latitude archipelagos. In this study of the Alexander Archipelago (AA) of Southeast Alaska, we address the impact of glacial cycles on geographic genetic structure for three mammals co‐distributed along the North Pacific Coast. We examined variation in mitochondrial and nuclear loci for long‐tailed voles (Microtus longicaudus), northwestern deermice (Peromyscus keeni), and dusky shrews (Sorex monticola), and then tested hypotheses derived from Species Distribution Models, reconstructions of paleoshorelines, and island area and isolation. In all three species, we identified paleoendemic clades that likely originated in coastal refugia, a finding consistent with other paleoendemic lineages identified in the region such as ermine. Although there is spatial concordance at the regional level for endemism, finer scale spatial and temporal patterns are less clearly defined. Demographic expansion across the region for these distinctive clades is also evident and highlights the dynamic history of Late Quaternary contraction and expansion that characterizes high‐latitude species. 相似文献
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The Puerto Rican frog, Eleutherodactylus coqui, has invaded Hawaii and has negatively impacted the state's multimillion dollar floriculture, nursery and tourist industries; however, little is known about the ecological consequences of the invasion. Using data from Puerto Rico and Hawaii, the authors summarize the potential consequences of the invasion and describe future research needs. It could be predicted that the coqui would reduce the abundance of Hawaii's endemic invertebrates. However, data suggest that coquis are mostly consuming non‐native invertebrates, and not invertebrate pests, such as mosquitoes and termites. Endemic invertebrates are likely to represent a portion of the coqui diet, but it remains uncertain which endemic invertebrates are most threatened by coqui predation and whether there will be indirect effects that benefit or harm them. It could be predicted that coquis would compete with endemic birds for invertebrate prey, but there is presently little overlap in the habitats used by coquis and endemic birds. Although, coquis may make bird re‐invasion into lowland ecosystems more difficult; alternatively, coquis could serve as an additional food source for some endemic birds. Finally, it could be predicted that coquis serve as a food source for endemic‐bird predators, such as rats and mongoose, and bolster their abundance. Preliminary data suggest that coquis will not bolster rat or mongoose populations. Managing coqui populations in Hawaii has been a challenge. A population has not yet been eradicated using citric acid, the only federally approved pesticide for coquis. It is unlikely that coquis will ever be eradicated from the islands of Hawaii and Maui, where there are now hundreds of populations. Quick and severe responses to new introductions may be the only effective means of containing the spread of the coqui. 相似文献
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The extent of extinctions of mammals on islands 总被引:2,自引:0,他引:2
Many of the world's oceanic and oceanic-like islands possessed endemic mammal faunas before they were colonized by humans. These faunas, unbalanced and impoverished compared to continental faunas, usually lacked large mammalian carnivores. In virtually all cases, the arrival of humans and their domesticants and commensals on these islands is related to the extirpation of large numbers of endemic insular mammals. These extinction events affected at least 27% of autochthonous mammal species on the world's oceanic and oceanic-like islands. This percentage rises the 35% when volant mammals are excluded. This reduction in the natural biodiversity brought about the disappearance of several unique biological types that apparently never existed on the continents. 相似文献
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本文重新描述了采自西沙群岛永兴岛的巨幽蛛属亚特巨幽蛛Artema atlanta Walckenaer,1837。描述标本保存在中国科学院动物研究所。亚特巨幽蛛Artema atlanta Walckenaer,1837(图1A-D,2A—D,3A-C)观察标本2♂,8♀,海南省西沙群岛永兴岛,2008-01—13—19,卜文俊 采集。 相似文献
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Camille Leclerc Sbastien Villger Clara Marino Cline Bellard 《Diversity & distributions》2020,26(4):402-414