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1.
螺髻山自然保护区非飞行小型哺乳动物垂直多样性调查   总被引:3,自引:0,他引:3  
2009 年4 ~8 月利用铗日法对螺髻山自然保护区非飞行小型哺乳动物的多样性进行了调查。调查于海拔1 800 ~4 150 m间按梯度设置7 个采集样地,每个采集样地内设3 个样带并置铗,有效布铗10 500铗次,捕获非飞行小型哺乳动物5 科8 属15 种,共491 个个体。调查结果表明,调查区域内非飞行小型哺乳动物群落的相对丰富度、丰富度和多样性指数均与海拔存在显著的相关性。统计分析显示:位于阴坡且与水源地相距较近的样地的物种相对丰富度明显高于位于阳坡、距离水源地远的样地;植被类型丰富、降水量充分的中海拔地区(2 200 ~ 2 600 m) 相对丰富度、丰富度和多样性达到最高;而在高海拔(> 3 800 m) 和低海拔区域(< 2 000 m)则较低。非飞行小型哺乳动物的多样性以中低山阔叶灌丛林与亚热带针阔混交林中最高,而在高山流石滩、高山草甸与河谷灌草丛中较低。在本研究的调查区域内,中海拔地区多样性和丰富度最大可能是非飞行小型哺乳动物垂直多样性分布的一个重要特点。  相似文献   

2.
历山森林群落物种多样性与群落结构研究   总被引:56,自引:1,他引:55  
采用多样性指数、丰富度指数和均匀度指数对山西历山森林群落物种多样性进行了研究.结果表明,各群落类型的物种多样性指数的顺序为:青榨槭+五角枫林>青榨槭+鹅耳枥林>辽东栎林>栓皮栎林>华山松+红桦林>油松+栎林>白桦林>侧柏+栓皮栎林>红桦林>华山松林>侧柏林>油松林>红桦+山杨林;森林群落灌木层多样性指数和丰富度指数大于草本层和乔木层,而均匀度指数在乔木层、灌木层和草本层则表现出多样化的趋势;海拔1 000~1 920 m之间,Shannon-Wiener指数、Hill多样性指数及物种丰富度与海拔梯度均呈正相关(P<0.05),海拔大于1 920 m则呈现负相关;这些指数沿海拔梯度的变化呈现出“中间高度膨胀”的规律,即中等海拔高度上物种多样性高而低海拔和高海拔物种多样性低.这主要是由于在中海拔(约1 900 m)地段水热条件组合较好,人类活动干扰较少所致.  相似文献   

3.
神农架南坡植物群落多样性的海拔梯度格局   总被引:35,自引:3,他引:32  
神农架南坡在我国植被区划中具有十分重要的意义。在神农架南坡沿海拔梯度设置50个样方进行植物物种多样性调查,通过对样方的数量分类和DCA排序,结合物种丰富度、区系分化强度、区系成分和生活型构成等方面的分析,研究神农架南坡植物物种多样性的垂直格局。结果表明:(1)神农架南坡的植被垂直带谱为:海拔900—1000m以下为常绿阔叶林;1000-1700m为常绿落叶阔叶混交林;1600—2100m为落叶阔叶林;海拔2000—2400m为针阔叶混交林;海拔2300m以上为暗针叶林。(2)植被基带群落中,在物种数量、区系成分和重要值方面,常绿和落叶阔叶树种所占的比例都相差无几。(3)植物多样性的垂直格局基本符合“单峰”模式。峰值出现在海拔1400—1500m;但混交林类型的多样性和区系分化强度较高。(4)在植物区系中,温带成分处于主导地位;世界广布属的比例随海拔上升而增加;而中国特有属仅见于海拔2000m以下。亚热带成分和东亚区域性区系成分都随海拔上升而减少,峰值都位于山地常绿落叶阔叶混交林。(5)蕨类植物丰富度随海拔上升而减小;草本植物丰富度与海拔高度之间没有呈现显著的相关关系;木本植物丰富度总体沿海拔梯度减少,但峰椎处于常绿落叶阔叶林带。针阔混交林样方的平均木本物种数也超过落叶阔叶林带。  相似文献   

4.
利用对铜壁关自然保护区多次考察形成的种子植物数据库,结合通过GIS生成的区域数字高程模型(DEM)数据,分析了该区域种子植物物种丰富度及物种密度沿海拔梯度的变化特征。结果表明, 科、属、种的丰富度随海拔的升高,先增加后降低,在中海拔区域达到最大值,科、种的丰富度最大值出现在海拔1400~1800 m的范围内,属的丰富度最大值出现在1000~1400 m的海拔范围。科、属、种的密度随海拔升高先下降后上升,再下降后再上升;且最大值都出现在保护区最高海拔3000~3400 m的范围内。物种丰富度和物种密度分布格局明显受到海拔梯度的影响,海拔梯度综合了水热条件等诸多因素。铜壁关种子植物科、属、种水平上的物种丰富度的海拔分布格局符合中域效应假说;同时还对目前常用的计算物种密度的"对数模型"方法的普遍适用性提出质疑。  相似文献   

5.
本研究采用垂直面取样法,对中国长白山北坡不同海拔及干扰程度下访花食蚜蝇群落的物种组成、多度、丰富度及多样性进行了调查研究。我们选择了不同垂直带的两个样地,分别位于800~1 100 m和1 750 ~2 150 m;每个样地选取3种生境类型,每一生境类型采样面积为20 m×20 m。252组调查数据表明,共采到访花食蚜蝇42种2 540个体。不同海拔生境访花食蚜蝇的组成、多度、丰富度及多样性的差异分析结果表明: 低海拔样地内不同生境访花食蚜蝇的群落相似性高于高海拔样地;低海拔样地访花食蚜蝇的多度高于高海拔样地,而物种丰富度低于高海拔样地;不同生境类型访花食蚜蝇多样性指数存在差异,但高海拔样地与低海拔样地多样性差异不显著;过渡林生境(岳桦林带)与次生林生境(针阔混交林带Ⅱ)中访花食蚜蝇的多样性较高。保护珍稀植物物种的人工植物花园访花食蚜蝇多样性仅次于过渡林生境(岳桦林带)与次生林生境(针阔混交林带Ⅱ),保护作用显著。  相似文献   

6.
在云南绿春县,采用网扫法调查了培育云南紫胶虫5年的天然次生林(样地Ⅰ)和培育3年(样地Ⅱ)、1年(样地Ⅲ)及未培育紫胶虫(样地Ⅳ)的人工林中的蝽类昆虫群落。共采集蝽类昆虫423头,隶属于7科,47种。4个样地蝽类昆虫群落的物种组成和多样性各不相同。天然次生林蝽类物种组成丰富,条棘缘蝽占有较突出优势而导致多样性不高;人工林中,样地IV蝽类物种最丰富,优势度最低,均匀度和多样性最高;样地III次之;样地II物种最贫乏,优势度最高,均匀度和多样性最低。可见,紫胶虫与其栖境内蝽类的竞争将导致蝽类昆虫群落物种丰富度及多样性下降。  相似文献   

7.
岛屿栖息地鸟类群落的丰富度及其影响因子   总被引:25,自引:4,他引:21  
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   

8.
为了解小相岭山系非飞行小型兽类物种丰富度的海拔梯度分布格局及物种更替情况,于2019年和2020年的7—9月通过夹日法对小相岭山系的小型兽类多样性及群落组成进行了调查,在海拔1 300~4 100 m段按照400 m的高差间隔设置样方53个,共捕获小型兽类317只,隶属于3目7科15属23种,其中,包括新记录滇攀鼠Vernaya fulva。小相岭山系非飞行小型兽类的物种丰富度和物种多样性在2 500~2 900 m出现峰值,并随海拔的升高递减,显示出右偏倚的中峰分布格局。相邻海拔间的物种更替也表现出β多样性在中海拔段更高。此外,小相岭山系整个海拔梯度上的群落相似性明显随海拔距离增加而衰减。本研究结果表明,在今后的生物多样性保护和管理工作中,需重点关注中海拔段。  相似文献   

9.
采用样带网格调查方法和α、β多样性指数分析方法,研究了长白山河岸带原始林和次生林群落木本植物多样性沿海拔梯度分布规律及其对采伐干扰的响应.结果表明:不同海拔区域河岸带原始林群落均由11~13个树种组成,其在群落中的地位随海拔升高而发生变化,阔叶树种优势地位逐步被针叶树种所取代,采伐干扰不仅改变了群落树种丰富度及其在群落中的地位,而且使针叶树种取代阔叶树种的趋势有所增强;河岸带原始林群落物种多样性沿海拔梯度呈现出中、低海拔区域相对较高且比较恒定(2.454~2.544),高海拔区域(2.250)下降的分布规律,采伐干扰改变了其沿海拔梯度分布格局(波动型),加大了不同海拔区域群落间的波动性(2.174~2.692);河岸带原始林群落树种沿海拔梯度的变动速率相对较低(1.5~3.5),且群落相似性较高(0.85~0.94),采伐干扰使次生林群落树种沿海拔梯度的变动幅度增大(0.5~6.0),群落相似性下降(0.68~0.91),但次生林群落沿海拔梯度分布仍具有较高连续性.  相似文献   

10.
神农架海拔梯度上的植物种域分布特征及Rapoport法则检验   总被引:1,自引:0,他引:1  
根据Rapoport法则, 动物、植物物种的纬度或海拔分布宽度存在着从高纬度或高海拔地区向低纬度或低海拔地区逐渐变窄的现象。本文基于物种的海拔分布数据, 分析了神农架维管束植物及不同种域宽度组的物种丰富度海拔格局; 采用已有的4种方法和本文改进的种域分组中点法, 分析了海拔梯度上种域宽度与种域中点的关系, 并检验其是否符合Rapoport法则。结果表明, 神农架地区维管植物丰富度的海拔梯度分布格局呈单峰型, 峰值在1,000–1,500 m; 不同种域组的物种丰富度分布具有类似的单峰格局, 但随着种域宽度减小, 其物种丰富度的峰值逐渐偏向低海拔。对于神农架的物种海拔分布数据, Stevens方法、Pagel方法和逐种方法的结果都支持Rapoport法则, 而中点法的结果主要反映中域效应的影响, 种域分组中点法可有效控制中域效应的影响, 但不支持Rapoport法则。上述结果表明, 对于Rapoport法则的检验亟待研究方法的改进; 而种域的海拔格局及其形成机制, 还需要更多案例的比较研究, 才能形成普遍性的认识。  相似文献   

11.
1IntroductionWildlifetradeisamain~mpetustoutilizewildlife.Thechangeinspeciesandvolumein-volvedinthewildlifetrademayreflectconservationstatus,dynamicsandexploitedlevelofwildliferesources.Thestudyonwildlifetradeisthetheoriticalbasisonwhichproposalsastolimittradeonrareorendangeredspeciescanbemade,andwithwhichfuturemonitoringofthetradecanbecompared.Theresultalsocanbeusedtoevaluateconservationeffectsofprotectionmeasuresandlawsforbiodiversityconservation.Itisofgreatsignificanceinguid-ingsustainable…  相似文献   

12.
1990年8月对梵净山和张家界两个自然保护区内蜘蛛群落进行调查,结果表明:自然保护区内蜘蛛资源极为丰富,经初步鉴定,计有蜘蛛27科85属180种,其中主要成分依次为肖蛸、园蛛、狼蛛、球蛛和皿蛛等。蜘蛛发生量折合每亩为17,585—54,000头。八个不同生境类型蜘蛛群落的种类数和密度存在明显差异;各种蜘蛛分布群在群落内的比例随栖息地结构变化而改变,因而也导致蜘蛛群落的Shannon-Wiener多样性指数,Simpson优势度和均等度等参数的变化。  相似文献   

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14.
This study describes the recolonization by a Sudano‐Sahelian rodent community of an area slashed and burned in the middle of the dry season (Gonsé Forest in Burkina Faso). A series of abundance cycles occurred. The first began with the wet season and the arrival of a succession of four species: Taterillus gracilis, Tatera guineae, Nannomys sp. and Mastomys erythroleucus. Taterillus gracilis appeared to be the least demanding species. It was sexually active whatever the season and took advantage of reduced competition among species on the burned tracts. Tatera guineae also extended its spatial distribution but failed to reproduce. Nannomys sp. rapidly increased after the first rains. Although generally held to be the most prolific and opportunistic of the species involved, M. erythroleucus only found conditions amenable to its colonization late on. The timing of the disruption and whether or not it coincides with the reproductive period and the mobility phase of each species are decisive factors. This information is useful for a clearer understanding of the dynamics of each species and for evaluating the risk and probable locations of outbreaks of certain species.  相似文献   

15.
明晰放牧干扰下高寒草甸植物丰富度与生物量的相关关系,为草地植物不同生长时期生物量的预测提供依据。设置6个放牧强度样地,连续3a放牧,2014年进行3个季节(6月、8月、10月)的植物丰富度和地上、地下生物量调查,对比分析放牧干扰下物种和生活型丰富度(生活型的种类)分别与地上、地下生物量的相关关系。结果表明:(1)物种和生活型丰富度与地上生物量均受放牧强度的显著影响,物种丰富度仅在8月与放牧强度显著负相关,生活型丰富度在10月随放牧强度单峰变化,地上生物量在不同季节均与放牧强度显著负相关,而地下生物量与放牧强度无关。(2)物种丰富度与地上和地下生物量均受季节的显著影响,物种丰富度和地上生物量仅在低强度放牧区随季节呈单峰变化,地下生物量在中等强度放牧区随季节呈单峰变化;生活型丰富度与季节无关。(3)放牧干扰前物种和生活型丰富度与地上和地下生物量均显著正相关。3a放牧后仅在8月,物种丰富度只与地上生物量显著正相关,生活型丰富度与地上和地下生物量均显著正相关。(4)对于不同放牧强度,物种丰富度仅在低强度放牧区与地上生物量显著正相关,而生活型丰富度在所有放牧强度区均与地上生物量显著正相关。综上所述,放牧干扰扰乱了高寒草甸丰富度与生物量之间的关系,尤其影响了物种丰富度与地下生物量之间的相关关系。生活型丰富度与地上生物量之间的显著关系不受放牧强度干扰,使生活型丰富度在预测生物量方面表现出优势。  相似文献   

16.
Abstract. Four contrasting ecotones were sampled to address three questions: (1) Are there ‘ecotonal’ species, (2) Do ecotones possess higher (or lower) species richness than the adjacent communities? and (3) Are exotic species more likely to occur in ecotones? One ecotone was edaphic, one was apparently caused by a positive‐feedback switch, one was environmental/anthropogenic and one was entirely anthropogenic. The exact position of each ecotone was established from the spatial change in ordination scores. Ecotonal species, in the sense of species mainly restricted to the ecotone at the site, were present in all four ecotones. All but one of the ecotonal species were native. The switch ecotone and the purely anthropogenic ecotone also contained native species that were significantly more frequent in the ecotone than in either adjacent community. Species richness was intermediate between that of the two adjacent communities in three of the ecotones. In the environmental/anthropogenic ecotone, species richness was higher than in adjacent communities, but not significantly so. There were appreciable numbers of exotic species in the two ecotones with anthropogenic influence, one of which had a proportion of exotic species intermediate between the two adjacent communities. Contrary to theory, the proportion of exotic species in the second ecotone was significantly lower than in either adjacent community. We conclude that all three features we examined depend on the particular ecological conditions and the ecology of the species present; they are not intrinsic properties of ecotones.  相似文献   

17.
《Ostrich》2013,84(3):267-276
The biodiversity of Akagera National Park (ANP), Rwanda, has reportedly been declining since 1990 due to conflict and war in the country between 1990 and 1994. In this paper, we describe bird diversity in the post-war recovery period. We used systematic plots, point counts and presence–absence surveys to estimate bird species richness and diversity in acacia savanna habitats of the park between 2009 and 2011. We recorded a total number of 301 species, of which 75% were resident and 22% migrant, including a large number of Palearctic visitors and Afrotropical migrants. Particularly notable were four endemic species of the Lake Victoria region, four globally threatened and nine near-threatened species as well as species that had not previously been recorded in the park and those overlooked by past records. Estimated species richness and diversity at the landscape level were 346 and 0.98, respectively, mean estimates per plot were 42 and 0.86 for species richness and diversity, respectively. Our results highlight regional and international importance of ANP in protecting important bird diversity. We also emphasise that ANP is the only savanna habitat in Rwanda where typical savanna birds occur. Our findings provide new insights for further strengthening of efforts to conserve the park's biodiversity.  相似文献   

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群落均匀度分形分析   总被引:7,自引:1,他引:6  
王永繁  余世孝  刘蔚秋 《生态学报》2003,23(6):1031-1036
修正了Frontier和Ricotta等关于有效物种丰富度指数A与物种丰富度指数S之间幂律关系的定义.探讨了A与S之间分形关系的生态学意义.认为分形维数D是群落均匀度测度值在物种数S不断增加的过程中.向其逼近的一个理论值;提出了利用双对数坐标上建立的A与S拟合直线的方程.对群落均匀度的4种变化趋势进行描述的方法。以广东黑石顶自然保护区森林演替系列为例.研究了针阔叶混交林和常绿阔叶林样带上.随着样带观察长度的逐渐增加群落均匀度的变化情况。结果表明.230m长的混交林样带只存在一个线性无标度区间.群落均匀度随样带长度的不断增加而逐渐降低.向分形维数D=0.810趋近。170m长的常绿阔叶林样带存在两个线性无标度区问.在0~25m的尺度域内.随着样带长度的逐渐增加均匀度不断降低.向分形维数D=0.525逼近;在30~170m的尺度域内.随着样带观察长度的增加.群落均匀度也逐渐增加.向分形维数D=0.920趋近。  相似文献   

20.
Aim We examined the relationship between host species richness and parasite species richness using simultaneously collected data on small mammals (Insectivora, Rodentia and Lagomorpha) and their flea parasites. Location The study used previously published data on small mammals and their fleas from 37 different regions. All the world's main geographical regions other than Australasia and Wallacea were represented in the study, i.e. neotropical, nearctic, palaearctic, oriental and afrotropical realms. Methods We controlled the data for the area sampled and sampling effort and then tested this relationship using both cross‐region conventional analysis and the independent contrasts method (to control for the effects of biogeographic historical relationships among different regions). Brooks parsimony analysis was used to construct a region cladogram based on the presence/absence of a host species and host phylogeny. Results Both cross‐region and independent contrasts analyses showed a positive correlation between host species richness and flea species richness. Conventional cross‐region regression under‐ or overestimated fleas species richness in the majority of regions. Main conclusions When the regression derived by the independent contrasts method was mapped onto the original tip data space, points that deviated significantly from the regression originated from Kenya, Mississippi and southern California (lower than expected flea richness) and Chile, Idaho, south‐western California and Kyrgyzstan (higher than expected flea richness). These deviations can be explained by the environmental mediation of host–flea relationships and by a degree of environmental variety in sampled areas.  相似文献   

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