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新疆喀纳斯自然保护区植物群落物种多样性及动态特征研究
【作者】 李永亮;
【导师】 岳明;
【作者基本信息】 西北大学 , 生态学, 2010, 硕士
【摘要】 对喀纳斯国家级自然保护区植物群落类型、结构、物种多样性、群落动态以及土壤因子与群落物种多样性指数之间的关系进行了调查研究。1.群落调查共发现高等植物171种,蕨类植物两种。在所有调查群落中,单种属科较多。植物的分布区类型以旧世界温带分布种和北极分布种占有明显优势。维管束植物生活型以地面芽植物占绝对优势。2.按照《中国植被》分类单位的划分标准,将喀纳斯国家自然保护区自然植被划分为6个植被型组,12个植被型,37个群系组或群系。在调查了代表性植物群落样方的基础上,采用双向指示种分析法(TWINSPAN)对所调查群落进行了数量分类。TWINSPAN将57个样方分为11组,结合区域内群落物种组成、生境等方面的特征,将所调查植物群落划分为4个植被型组,18个群系或群系组。3.对于森林群落,在不同垂直分层中,各垂直层多样性指数之间差异显著,Shannon-Wiener指数、Margalef吻种丰富度指数和Pielou均匀度指数Jh都是草本层最大,Simpson指数则是草本层最小。物种多样性指数和均匀度指数在群落间变异系数表现为乔木层和灌木层较大。不同类型的群落之间多样性指数差异不显著。4.研究了不同强度旅游干扰对本区森林、草甸和灌丛的群落物种组成、物种多样性以及土壤理化性质的影响。结果表明:1)在不同强度的干扰下,云杉林中灌木层与草本层物种组成存在显著差异(p<0.05),随着干扰强度的增大,群落物种多样性呈先上升后下降的变化;2)草甸群落Shannon-Wiener多样性指数随干扰强度的增大有下降趋势;3)金露梅群落在不同的干扰强度下,群落优势度、均匀度和土壤理化性质均因旅游干扰而显著降低(p<0.05):4)土壤理化性质的改变在一定程度上也改变了群落的物种多样性。5.对河漫滩湿地植物群落进行了调查取样,通过除趋势对应分析(detrended correspondence analysis, DCA)排序研究了群落演替的动态和方向,同时分析了物种多样性在群落演替过程中的动态变化,并运用去势典范对应分析(detrended canonical correspondence analysis, DCCA)方法,分析了不同样方中土壤因子与群落多样性指数之间的关系。结果表明:1)该区域植物群落演替序列为泽生苔草群落→西伯利亚早熟禾群落→金露梅群落→沼桦群落→西伯利亚云杉群落;2)随着演替的进行,群落物种优势度显著增加,而物种多样性呈先增加后降低的趋势,金露梅群落最高;3)土壤含水量和群落物种优势度之间存在显著负相关关系。
【Abstract】 Plant community type、structure, species diversity, community dynamics and the relationship between soil factors and species diversity have been studied in Kanas Nature Reserve for the first time.1. In the community survey we totally found 171 species of higher plants and two kinds of ferns. In all investigated communities, single species families holded a larger majority. The Old World Temperate Zone and Arctic species distribution dominated in the type of plant distributions. The life form of hemicryptophyte is reign supreme in all vascular plant.2. Accordance with the classification principle of the China Vegetation, in the Kanas National Nature Reserve, the vegetation is divided into six vegetation type groups,12 vegetation types,37 formation groups or formations. The vegetation in Kanas Nature Reserve were sampled and investigated. A quantitative classification of the plant communities was performed with TW1NSPAN(Two Way Indicator Species Analysis)method. The results showed that 57 quadrates were divided into 11 groups, the vegetation in Kanas Nature Reserve were divided into 4 vegetation types and 18 formations. The characteristics of communities were also described in detail.3. The results of the species diversity index analysis of the 18 kinds of plant community types in Kanas showed that 1) the diversity index in different vertical layer for forest communities are significant difference, Shannon-Wiener index, Margalef species richness index and Pielou evenness index Jh are the largest in herb layer, Simpson index is the smallest in herb layer; 2) The coefficient variation of the species diversity index in the arbor layer and shrub layer are larger than the herb layer among forest communities; 3) The species diversity index among different communities were not significant different.4. The different disturbance of tourism on the species composition, species diversity and soil in the Picea obovata communities, meadow and Potentilla fruticosa communities in Kanas Nature Reserve were studied. The results showed that the species composition of the shrub layer and herb layer were affected significantly by tourist disturbance in the P. obovata communities, and the species diversity was decreased and then increased slightly with increasing of the tourist disturbance. In meadow community, the Shannon-Wiener diversity index (H) was trended down with the increasing of disturbance. As for P. fruticosa community, Simpson index (D) and Pielou index (Jd), and the soil fertility were decreased noteblely by disdurbance of tourism. The changes of physicochemical characteristics of soil influenced the species diversity of communities.5. The floodplain wetlands which located on north end of Kanas lake were surveyed and DCA (detrended correspondence analysis) ordination technique was employed to clarify the dynamics and direction of community succession, meanwhile, the Shannon-Wiener diversity index, Margalef’s richness index, Simpson’s diversity index and Pielou’s evenness index were introduced to analyze the dynamics of species diversity in community succession. The relationship between soil factors and species diversity were also analyzed by using DCCA (detrended canonical correspondence analysis). The results showed that 1) the successional sequence of plant communities in this region was community Carex melanostachya→community Poa sibirica→community Potentilla fruticosa→community Betula humilis→community Picea obovata; 2) Along wtih the succession progressed, the species dominance increased significantly, while species diversity increased first and then showed a falling trend, with a peak at phase of community Potentilla fruticosa; 3) there is significant negative correlation between water content of soil and species dominance.
【Key words】 Kanas Nature Reserve; species diversity; tourism disturbance; community dynamic;