桑植石漠化林地植物多样性及群落数量特征分析

以湖南桑植县石漠化区为研究对象,采用样方调查法对3个不同石漠化等级样地进行植被调查,分析不同石漠化等级植物物种组成结构及植物多样性指数差异,并根据Jaccard群落相似性原理进行不同石漠化等级植物群落间的相似度评价分析.结果表明:调查区共出现草本植物23科39种、木本植物26科38种,优势科为菊科、蔷薇科、百合科、禾本...

Analysis on quantitative characteristics and species diversity of rocky desertification forest land in Sangzhi County

In order to provide theoretical basis for ecological protection and ecosystem restoration and reconstruction of rocky desertification forest land in Southwest China,the diversity of rocky desertification forest land in Sangzhi of Hunan Province was investigated to analyze the species composition and structural characteristics of vegetation.Three communities of different grades of rocky desertification in Sangzhi conutry were investigated by using the sampling survey method.The species composition,floristic characteristics,species diversity and the similarity among the three communities were investigated,which was evaluated by the principle of Jaccard community similarity.There were 22 families,39 species of herbaceous plants and 26 families,38 species of woody plants in the studied areas,among which Rosaceae,Liliaceae,Compositae,Gramineae and Pteridaceae families dominated the plant layer,accounting for 29.9%of the number of species.With the increase of rocky desertification,plant species and number decrease.On the whole,plant species in the area with severe rocky desertification were relatively few with simple community composition and structure,low species diversity and fragile ecology with the highest diversity index-H of 2.15,the highest richness index-R of 5.03,and the highest evenness index of 0.66.There were no significant differences except the richness index-R showed significant differences.The richness index of rocky desertification was order:low>middle>high.The similarity of rocky desertification plant communities of different grades was the same at the level of families,genera and species,which can be ordered:middle-high>low-middle>low-high.On the whole,the similarity coefficient of different levels of rocky desertification community plots were 0.30~0.50,while the community similarity was generally reduced with the increase of the level spacing of rocky desertification.Therefore,the community similarity between light and heavy is the lowest.