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1.
在野外样方调查的基础上研究了大青沟国家自然保护区5种不同植被类型地面生苔藓植物物种多样性及其与环境因子之间相关性。(1)共发现苔藓植物12科27属55种,以丛藓科(Pottiaceae)、青藓科(Brachytheciaceae)和真藓科(Bryaceae)等为优势科,青藓属(Brachythecium)、真藓属(Bryum)和小石藓属(Weissia)等为优势属,优势种有双色真藓(Bryum bicolor)、西伯利亚瘤冠苔(Mannia sibirica)、密叶绢藓短柄变种(Entodon compressus var.zikaiwiensis)、绒叶青藓(Brachythecium velutinum)和地钱(Marchantia polymorpha)等;(2) Alpha多样性指数中,Patrick丰富度指数6~29,Shannon-Wiener多样性指数1.439 2~2.608 0,变化规律均为:水曲柳林(Fraxinus mandschuria forest) > 蒙古栎林(Quercus mongolica forest) > 大果榆林(Ulmus macrocarpa forest) > 西伯利亚杏灌丛(Armeniaca sibirica shrub) > 羊草草地(Leymus chinensis community);Simpson优势度指数0.131 6~0.295 5,与上述两指数呈显著负相关;Pielou均匀度指数0.663 0~0.803 3,与以上指数相关性不强;(3)影响物种多样性的主要环境因子有空气湿度、土壤水分、乔木盖度和灌木盖度;(4) Bata多样性指数0~0.652 2,大果榆林与蒙古栎林之间相似度最大,羊草草地与水曲柳林之间无相似性;水曲柳林和蒙古栎林是研究区地面生苔藓植物物种多样性保护的重点。  相似文献   

2.
对赤水桫椤国家级自然保护区18个桫椤植物样方苔藓植物进行采集,共获165份标本。经鉴定分析,有苔藓植物26科37属61种,其中苔类植物8科10属16种,藓类植物18科27属45种;优势科有5个,分别是齿萼苔科、白发藓科、凤尾藓科、毛锦藓科、灰藓科;优势属有5个,分别是白发藓属Leucobryum、梳藓属Ctenidium、曲柄藓属Campylopus、凤尾藓属Fissidens、异萼苔属Heteroscyphus;苔藓植物种类较丰富的样方多位于沟边、沟谷潮湿的地带,在草本、蕨类、小灌木等小型植物少、桫椤植物幼苗少及腐殖质层厚的环境中,苔藓植物分布也较多;生境分析结果显示,石生基质种类最多,占总种数的85.25%。  相似文献   

3.
拉鲁湿地主要植物群落结构及物种多样性   总被引:2,自引:0,他引:2  
李春  周刊社  李晖 《西北植物学报》2008,28(12):2514-2520
2002年6~9月对拉鲁湿地植物种类、群落结构、生物量以及物种多样性进行了调查研究.结果表明:(1)拉鲁湿地共有植物30科52属85种,主要有芦苇[Phragmites australis(Cav.)Trin.ex Steud.](A)、尼伯尔酸模(RumexnepalensisSpreng)(B)、水葱(Scirpus validusVahl)(C)、穗状狐尾藻(MyriophyllumspicatumL.)(D)、灯芯草(Juncus effususL.)(E)、针叶苔草(CarexonoeiFranch.et Sav.)和黑褐苔草(CarexatrofuscaSchkuhr)(F)、藏北嵩草(KobresialittledaleiC.B.Clarke)(G)、藏蓟[Cirsiumlanatum(Roxb.ex Willd.)Spreng.](H)等8个主要植物群落.(2)在8个主要植物群落中,嵩草群落所含物种数最多,为44种,穗状狐尾藻群落最少,仅8种;芦苇群落生物量最高,为124.5~1 027.0 g/m2,藏蓟群落生物量最低,为124.5~220.5 g/m2;优势种芦苇的生物量最高,为183.5~660.0 g/m2,藏蓟生物量最低,为43.1~76.3 g/m2.(3)各群落的垂直结构特点是:芦苇群落、水葱群落、穗状狐尾藻群落具有挺水层、浮叶层和沉水层,其他群落只具有可分为高、低两层的草本层.(4)在各群落的相似性方面,嵩草群落与藏蓟群落、水葱群落与芦苇群落和尼伯尔酸模群落的相似性要明显高于其他群落,其Jaccard系数分别为0.549 0、0.538 5、0.500 0;芦苇群落、尼伯尔酸模群落、水葱群落、穗状狐尾藻群落与藏蓟群落以及芦苇群落、穗状狐尾藻群落与嵩草群落在建群种上没有相似之处,Jaccard系数为0.  相似文献   

4.
We studied temporal and spatial dynamics of extremely diverse moth ensembles (Lepidoptera: Pyraloidea) along a gradient of forest disturbance ranging from undisturbed primary tropical rain forest to different kinds of modified forest and open cultivated land at the margin of Mount Kinabalu National Park (Sabah, East Malaysia). We sampled moths by light trapping during two periods (March‐May and August‐September 1997). We collected a total of 7724 individuals representing 680 species during 78 light‐trapping nights at six study sites. Species diversity (Fisher's α) of ensembles in undisturbed primary forest was distinctly higher than in disturbed or secondary forest. More pyraloid moths were attracted in undisturbed primary forest. Samples from disturbed primary or old‐growth secondary forest were statistically indistinguishable from the undisturbed primary forest ensemble in regard to species composition. Thus, pyraloid ensembles from disturbed forest with tall trees remaining appeared to represent impoverished subsets of the undisturbed primary forest community. The more heavily disturbed sites had a distinct fauna and showed a stronger faunal differentiation among each other. Four species of the genus Eoophyla, in which aquatic larvae feed on algae in fast‐running streams benefited prominently from forest disturbance. Temporal variation of ensembles was remarkably concordant across the disturbance gradient. Relative abundance variation of the commonest species was identical at all sites. Overall, pyraloid moths responded more sensitively to anthropogenic habitat alteration than most other moth taxa studied thus far in tropical regions and allowed for an analysis of diversity patterns at a high temporal resolution.  相似文献   

5.
为了寻求有害蝗虫的防治对策,深入研究蝗虫生物多样性,用多样性指数、相似性分析等方法比较分析了延安北洛河流域不同生境中蝗虫群落组成。结果表明:草地中占有的属种数量均最高,灌草丛和农田中蝗虫的科属种都相对较低。不同生境蝗虫多样性指数的排列顺序为草地>河滩>灌草丛>农田,草地的多样性指数最高,农田的多样性指数最低。丰富度指数的变化趋势与多样性指数一致,而优势度指数却恰好与二者的顺序相反。在相似性分析中,草地和河滩相似性系数最大,说明草地和河滩这两种生境蝗虫种类组成的相似性较大,具有更多的共同种,从而可以推知草地和河滩的生境条件有一定的相似性,而农田和草地是两种完全不同的生境。  相似文献   

6.
Beta diversity can be measured in different ways. Among these, the total variance of the community data table Y can be used as an estimate of beta diversity. We show how the total variance of Y can be calculated either directly or through a dissimilarity matrix obtained using any dissimilarity index deemed appropriate for pairwise comparisons of community composition data. We addressed the question of which index to use by coding 16 indices using 14 properties that are necessary for beta assessment, comparability among data sets, sampling issues and ordination. Our comparison analysis classified the coefficients under study into five types, three of which are appropriate for beta diversity assessment. Our approach links the concept of beta diversity with the analysis of community data by commonly used methods like ordination and anova . Total beta can be partitioned into Species Contributions (SCBD: degree of variation of individual species across the study area) and Local Contributions (LCBD: comparative indicators of the ecological uniqueness of the sites) to Beta Diversity. Moreover, total beta can be broken up into within‐ and among‐group components by manova , into orthogonal axes by ordination, into spatial scales by eigenfunction analysis or among explanatory data sets by variation partitioning.  相似文献   

7.
为了揭示喀斯特石漠化地区苔藓植物的物种多样性,通过野外实地调查对贵州喀斯特地区不同程度石漠化区域苔藓植物进行研究。结果表明,苔藓的科、属、种数量随着石漠化程度加剧而下降,其中,强度石漠化的科数最少且显著低于其他三种石漠化类型,比潜在、轻度、中度石漠化地区苔藓科数分别降低70.00%、57.14%、33.33%;轻度石漠化地区的真藓科、青藓科、丛藓科、曲尾藓科等包含属数较多,占总属数34.62%;Shannon-Wiener指数和Simpson指数变化基本一致,随石漠化程度加剧而下降,其中苔藓植物在潜在石漠化地区Shannon-Wiener指数为1.9393,高于其他三种石漠化区域,比强度石漠化区高43.97%,Simpson指数以轻度石漠化过渡到中度石漠化地区物种丰富度下降最快,下降26.73%;潜在石漠化区较其他三个区域拥有更高的苔藓数量。说明苔藓植物的分布和石漠化程度密切相关,随着石漠化程度加重,苔藓植物的科、属、种总数均有不同程度下降。  相似文献   

8.
闽北地区森林群落物种多样性的测定   总被引:2,自引:0,他引:2  
采用8个物种多样性指数对闽北地区的8个森林群落类型物种多样性进行测定,并选用4个种一多度关系模型(对数正态分布、Weibull分布、对数级数分布、生态位优先占领模型)分析其物种-多度关系,把多样性指数与对数正态分布、Weibull分布和生态位优先占领模型的有关参数进行线性回归,以分析多度模型参数描述物种多样性的可行性。结果表明:(1)多数物种多样性指数对群落的测度是一致的,(2)对数正态分布、Weibull分布和生态位优先占领模型对8个群落的物种多度拟合效果很好;(3)对数正态分布、Weibull分布和生态位优先占领模型有关模型参数与部分物种多样性指数的线性关系达显著或极显著水平。通过闽北地区8个类型森林群落物种多样性指数测定,使生物多样性较准确地数量化,同时还说明采用改进单纯形法进行非线性分布函数的拟合是简单有效的,可推广应用。  相似文献   

9.
太行山南段森林群落物种多样性研究   总被引:12,自引:4,他引:12  
分别用多样性指数、丰富度指数、均匀度指数对山西太行山南段森林群落的物种多样性及其与环境的关系进行了分析.结果表明:(1)3个植被型的物种多样性指数的顺序为:落叶阔叶林>温性针阔叶混交林>温性针叶林.(2)落叶阔叶林中各群系的物种多样性指数的顺序为:漆树 青麸杨林>鹅耳枥 青榨槭林>青檀林>辽东栎林>栓皮栎林>白桦林>红桦林>山杨 白桦林.(3)温性针叶林中各群系的物种多样性指数的顺序为南方红豆杉林>油松林>白皮松林>侧柏林.(4)物种丰富度指数在群落梯度上的总体趋势表现为草本层>灌木层>乔木层;多样性指数的趋势则为灌木层>乔木层>草本层;各群落灌木层物种均匀度指数大于乔木层和草本层,乔木层均匀度与草本层相差不明显.(5)各群落多样性指数在海拔梯度上表现出明显的规律,呈单峰曲线变化,即中等海拔高度上的群落物种多样性较高,而高海拔和低海拔多样性较低,这主要是由于在中海拔(大约1 500 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   

10.
吴萍萍 《植物研究》2018,38(2):195-200
在野外调查的基础上,应用Patric丰富度指数(R0)、Simpson指数(λ)和Shannon-Wiener多样性指数(H')、Pielou均匀度指数(E1)和Alatalo均匀度指数(E5)等对山西历山千金榆群落物种多样性进行了分析研究。结果表明:(1)千金榆群落R0、H'、E1和E5等多样性指数变化趋势基本一致,λ与H'等指数变化趋势相反;综合考虑:千金榆群落的物种多样性顺序为群丛Ⅰ(千金榆-山胡椒-糙苏群丛) > 群丛Ⅲ(千金榆-连翘-糙苏群丛) > 群丛Ⅳ(千金榆-土庄绣线菊+连翘-鹿药群丛) > 群丛Ⅶ(千金榆-接骨木-贝加尔唐松草+淫羊藿群丛) > 群丛Ⅱ(千金榆-小花溲疏-糙苏群丛) > 群丛Ⅵ(千金榆-小花溲疏-香根芹群丛) > 群丛Ⅴ(千金榆-小花溲疏-鹿药群丛);(2)乔木层多样性与灌木层多样性、草本层多样性呈负相关(P<0.05),而灌木层多样性与草本层的多样性相关不显著(P>0.05);(3)千金榆各群丛间多样性指数差异不显著。  相似文献   

11.
Recent studies have reported a consistent pattern of strong dominance of a small subset of tree species in neotropical forests. These species have been called “hyperdominant” at large geographical scales and “oligarchs” at regional‐landscape scales when being abundant and frequent. Forest community assembly is shaped by environmental factors and stochastic processes, but so far the contribution of oligarchic species to the variation of community composition (i.e., beta diversity) remains poorly known. To that end, we established 20.1‐ha plots, that is, five sites with four forest types (ridge, slope and ravine primary forest, and secondary forest) per site, in humid lowland tropical forests of southwestern Costa Rica to (a) investigate how community composition responds to differences in topography, successional stage, and distance among plots for different groups of species (all, oligarch, common and rare/very rare species) and (b) identify oligarch species characterizing changes in community composition among forest types. From a total of 485 species of trees, lianas and palms recorded in this study only 27 species (i.e., 6%) were nominated as oligarch species. Oligarch species accounted for 37% of all recorded individuals and were present in at least half of the plots. Plant community composition significantly differed among forest types, thus contributing to beta diversity at the landscape scale. Oligarch species was the component best explained by geographical and topographic variables, allowing a confident characterization of the beta diversity among tropical lowland forest stands. Abstract in Spanish is available with online material.  相似文献   

12.
广西中越边境喀斯特地区叶附生苔类植物物种多样性研究   总被引:1,自引:0,他引:1  
为了解日益恶化的喀斯特环境下叶附生苔类植物的分布状况,对广西中越边境喀斯特地区叶附生苔类植物多样性展开调查。结果表明,广西中越边境喀斯特地区有叶附生苔类植物5科15属43种,其中,九洲疣鳞苔(Cololejeunea yakusimensis)、巴氏薄鳞苔(Leptolejeunea balansae)、斯氏唇鳞苔(Cheilolejeunea streimannii)、麦氏细鳞苔(Lejeunea micholitzii)、巨齿细鳞苔(L.kodamae)和纤细细鳞苔(L.exilis)为广西苔藓植物新记录。该地区叶附生苔类植物区系具有热带性质和东亚分布特点。与邻近地区比较,该地区叶附生苔类植物与贵州茂兰的亲缘关系和区系关系最紧密。该地区叶附生苔类植物分布随海拔增加呈增加趋势。那坡老虎跳保护区、龙州和宁明弄岗保护区以及靖西龙邦镇风水林是叶附生苔类植物分布最丰富的地区,因此,建议应对这些地区的叶附生苔类植物进行优先保护。  相似文献   

13.
The distribution and species diversity of plant communities along a 600 km transect through the northeastern Tibetan Plateau (32°42′–35°07′ N, 101°02′–97°38′ E) with altitudes from 3255 to 4460 m are described. The transect started from the Youyi Bridge of Banma through Dari, Maqin and Maduo to Zaling Lake. The data from 47 plots along the transect are summarized and analyzed. The mean annual temperature, the mean annual rainfall and the length of growing season decreases from 2.6 to −4.5 °C, from 767.2 to 240.1 mm, from 210 to 140 days, respectively, along the transect from the southeastern Banma to northwestern Zaling Lake. The number of vascular plant species recorded in 47 plots is 242 including 2 tree, 34 shrub, 206 herb species. Main vegetation types on the transect from southeast to northwest are: Sabina convallium forest, Picea likiangensis forest, Pyracantha fortuneana + Spiraea alpina shrub, Hippophae neurocarpu shrub, Sibiraea angustata + Polygonum viviparum shrub, Stellera chamaejasme herb meadow, Potentilla fruticosa + Salix obscura + Carex sp. Shrub, Kobresia capillifolia meadow, P. froticosa + Kobresia humilis shrub, Caragana jubata + S. obscura shrub, Kobresia tibetica meadow, Kobresia pygmaea meadow, K. pygmaea + Stipa purpurea steppe meadow, Stipa purpurea steppe. Plant richness and diversity index all showed a decreasing trend with increasing of elevation along transect from southeast to northwest. Detailed information on altitudinal ranges and distribution of the alpine vegetation, vascular flora and environments over the alpine zone at northeastern Tibetan Plateau provides baseline records relevant to future assessment of probable effects of global climate changes.  相似文献   

14.
深圳马峦山华南紫萁群落及其物种多样性特征研究   总被引:1,自引:0,他引:1  
对深圳马峦山地区华南紫萁占优势的植物群落进行研究,结果表明:华南紫萁群落中共有维管植物48科69属82种,种类组成具有明显的南亚热带性质;年龄结构显示群落的主要优势种属于稳定型种群,群落总体处于稳定状态;群落的频度指数规律为A>B<C>D>E,与RaunKiaer频度定律、海南岛山地雨林优势种群的频度规律等不相符合;华南紫萁种群树高和个体数百分比显示,种群高度0.3~0.7 m植株占比例较大,种群处于旺盛发展期;物种多样性指数为SP=16.42,SW=4.56,均匀度指数为E=0.33,E′=0.83,群落物种多样性指数和均匀度指数均较高,接近典型南亚热带常绿阔叶林顶极群落类型。本研究揭示了华南紫萁野外生存状态,为该种的保护和利用提供了基础资料。  相似文献   

15.
为了解贵州百里杜鹃自然保护区不同演替阶段植物群落物种多样性特征,该研究采用“空间代替时间”的方法,对该保护区内5个演替阶段的群落进行调查,并分析其物种组成、重要值、α及β多样性特征。结果表明:(1)研究区共调查到维管束植物56科103属140种,优势科有蔷薇科、杜鹃花科和百合科。(2)杜鹃花科植物在整个演替过程中占据综合优势地位,在各演替阶段灌木层重要值均排前三位。(3)沿进展演替方向,群落的Margalef丰富度指数(dMa)、Shannon-Wiener多样性指数(H′e)、Simpson指数(D)及Pielou均匀度指数(Je)均呈现先上升后下降再上升的趋势,最后群落结构趋于复杂,稳定性上升。(4)随着演替的正向进行,群落间丢失和增加的物种数逐渐变多,物种替代率逐渐升高;物种相似性系数在整个演替过程中不相邻阶段间均表现为极不相似。研究认为,保护区应制定合理的保护措施,避免人为活动的破坏,提升群落稳定性,保护群落结构及物种多样性,为发挥生态功能及可持续发展提供科学支撑。  相似文献   

16.
叶附生苔植物物种多样性分布格局及生态成因   总被引:1,自引:0,他引:1       下载免费PDF全文
叶附生苔植物(以下简称叶附生苔)是一类附生在维管植物叶片表面的、一般只出现在热带雨林和常绿阔叶林中的苔类植物。它们具有重要的生态功能, 如影响碳、氮、水循环, 对气候变化和森林破碎化反应敏感, 可用作环境变化的指示植物。该文对叶附生苔的形态特性、物种多样性的研究历史和进展、地理分布格局, 以及对环境的要求(附主和生境的特性)等进行了综述, 探讨了叶附生苔多样性分布格局形成的可能原因, 即环境(空气湿度高、林冠层发育好、干扰少)和适应特征(无性繁殖、形体微小)的选择。根据全球叶附生苔研究进展状况及所存在的问题提出未来可开展的研究方向, 如叶附生苔的形成原因、与附主间的物质交换和能量流动机制、在森林生态系统中的生态功能、气候变化指示作用研究等, 大尺度上的研究也值得关注。  相似文献   

17.
为深入了解紫金山国家森林公园苔藓植物资源,对南京紫金山展开苔藓植物野外调查,应用典范对应分析(CCA)研究苔藓植物分布与环境间关系。结果表明,调查中共记录苔藓植物23科37属65种,青藓科(Brachytheciaceae)、丛藓科(Pottiaceae)、羽藓科(Thuidiaceae)和绢藓科(Entodontaceae)为优势科(≥6种),绢藓属(Entodon)、青藓属(Brachythecium)、匐灯藓属(Plagiomnium)和真藓属(Bryum)为优势属(≥4种);苔藓植物生境以土生为主,树生较少;苔藓植物生活型以交织型和丛集型为主,占比分别达46.15%和35.38%;苔藓植物区系以温带和东亚成分为主,区系成分呈现明显过渡性;CCA排序结果表明,湿度、坡向和海拔是影响该区域苔藓植物分布的主要环境因子。  相似文献   

18.
稀有植物十齿花群落物种多样性研究   总被引:6,自引:0,他引:6  
林长松  左经会  廖雯 《植物研究》2008,28(3):353-358
运用样方法对贵州省玉舍国家级森林公园稀有保护植物十齿花(Dipentodon sinicus)群落的物种多样性进行了研究,结果表明:玉舍国家级森林公园十齿花群落以蔷薇科、杜鹃花科、壳斗科、桦木科、山茶科、樟科、忍冬科、山茱萸科等为优势科;10个样地中有8个样地以十齿花种群占绝对优势,其平均重要值高达135.69,远远高于其它种群;十齿花群落乔木层物种丰富度为2.847、Simpson指数为0.601、Shannon-Wiener指数为1.523、种间相遇机率为0.601、均匀度指数为0.569,总体上均小于灌木层(分别为:5.580、0.830、2.377、0.829、0.672),表现为较明显的亚热带常绿落叶阔叶混交林的物种多样性特征。10个样地中,Q1的物种多样性程度最高,Q3次之,Q5和Q6最小,多样性程度最低,10个样地的物种多样性排序为Q1>Q3>Q9>Q7>Q2>Q4>Q10>Q8>Q5>Q6。  相似文献   

19.
This study examine the notion of plant community complexity in a broad sense and develop a new measure based on the average length L(S) (L(S)=∑ qj=1p jl j ) of the communication-theoretical parsimonious code required to describe the community (S). Total complexity may be differentiated into organized and unorganized complexity. The author refers to Shannon-Wiener entropy H(S) (H(S)=-∑ qj=1 p j log 2 p j ) and Renyi entropy H 12 (S) (H α(S)=11-αlog 2∑ qj=1 p α j , where α =12) as “disorder-based complexity", L(S) as “total complexity" and the difference Δ(S)=L(S)-H(S) and Δ 12 (S)=L(S)-H 12 (S) as “structural complexity". The complexity and diversity of typical plant communities along the NECT (Northeast China Transect) were discussed. The results suggest that structural complexity is higher in the lightly grazed grassland than the heavily grazed grassland. Clearly, structural complexity and disorder-based diversity are not substitutes for one another and should be considered as autonomous, equally important properties. Δ 12(S) measures a community complexity distinct form the disorder-based complexity H 12 (S) .  相似文献   

20.
中国东北样带(NECT)植物群落复杂性与多样性研究   总被引:18,自引:0,他引:18  
在更广的意义上考虑群落复杂性的概念,将群落总复杂性分离为基于无序的复杂性和结构复杂性,并以群落的两个原始数据-群落组分(例如种群)数和各组分个体的比例分布为基础,用描述群落的最小剩余码的平均码长L(S)=q/∑/j=1pjlj(其中lj为物种S的相对多度的Huffman码字长度,q是物种数,pj满q/∑/j=1pj=1)测度群落总复杂性,用Shannon-Wiener熵H(S)=-q/∑/j=1p  相似文献   

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