Keywords: 
• forest ecology /
• rocky desert /
• ecological community /
• α diversity /
• β diversity

Abstract: The diversity of plant species in 21 plots （5 000 km2） from Southern Hunan area was determined by calculating the indices of species diversity, richness, evenness, and dominance. Analysis included and diversity analyses with the Simpson （S）, Shannon-Wiener （SW）, Cody （C）, and Jaccard （J） Index. For rocky desert treatment and searching the regularities of growth and distribution of plant in rocky desert, applied with random quadrat sampling method and analysis by synthesis method. Results show there are overall presence of 63 families, 131 genera, and 173 species of vascular plants, 1） This included 15 families, 21 genera, and 24 species of trees; 34 families, 60 genera, and 74 species of shrubs; 32 families, 54 genera, and 63 species of herbs; 13 families, 22 genera, and 33 species of interlayer. 2） The shows that rocky desert area with low species richness （S = 0.796 9－0.936 1, SW = 2.104 7－3.274 6） and a simple community structure with individual species having a relatively uniform distribution but a higher community diversity. Species composition for the tree layer was greatest in the potential rocky desert area（S = 3.274 6 and SW = 0.936 1）. At the community level, most of the trees were in the potential rocky desert. 3） The showed that environmental differences between different sample plot. The C Index revealed that, form light to severe desert area has different numbers species, the similarity coefficient of different rocky desert spot decreased. The J Index of different level rocky shows the maximum is of 7.29 times to the minium. Conclusion which plants species are suitable in rocky desertification areas, contain the expansion trend of rocky desertification, improve the environment.［Ch, 1 fig. 3 tab. 25 ref.］