Study On Species Diversity Of Main Forest Communities And Relationships Of Main Secondary Forest Populations In Forest Region Of Kuanba

Applying quadrat methods, this paper analyzed the main forest community types, studied the species diversity of different communities , niche of main secondary forest populations and interspecific association of tree species of secondary forest in the forest region of Kuanba .The results were as follows:(1) Among the three plantation communities, in tree layer ,Cryptomeriafortunei-Cunninghamia lanceolata mixed forest community had the highest richness and Shannon-Wiener index ,and Phellodendron amurense Plantation community had the lowest richness and Shannon-Wiener index ,but in shrub and herb layers , Phellodendron amurense plantation community had the highest richness and Shannon-Wiener index,and Cryptomeria fortunei-Cunninghamia lanceolata mixed forest had the lowest richness and species diversity index . Between their tree and shrub layers, the difference of evenness index was significant and the difference of dominance index was more significant .Between their tree and herb layers, Shannon-Wiener index and evenness index were all significant .Between shrub and herb layers ,the difference of each index was not significant The total richness index and Shannon-Wiener index of Phellodendron amurense plantation community were all the highest than those of the other communities.(2) The total richness index of Machilus pingii- Quercus oxyodon evergreen broad-leaved forest community, Alnus cremastogyne-Betula luminifera-Quercus oxyodon evergreen-deciduous broad-leaved forest community and Rhus potaninii- Juglans sigillata- Quercus oxyodon evergreen-deciduous broad-leaved forest community all exceeded 31 .These communities , the dominance species in their shrub layers is Fargesia rufa ,such as Betula luminifera-Rhus chinensis-Quercus oxyodon evergreen-deciduous broad-leaved forest community, Quercus oxyodon-Litsea pungens-Cornus macrophylla evergreen-deciduous broad-leaved forest community, Cornus macrophylla- Acer caudatum var. prattii- Ailanthus altissima deciduous broad-leaved forest community and Cerasus trichostorna-Cerasus dielsiana-Acer caudatum deciduous broadleaved forest community , had lower total richness and Shannon-Wiener index .Accordingly, these communities had higher dominance index. The richness index of shrub was higher than that of tree layer in each secondary forest community .Through T test, the difference of richness index between their tree and shrub layers was significant, and the difference of richness between their tree layer and herb layer is significance too. And the difference of Shannon-Wiener index between their tree and shrub layers is more significant. The difference of Shannon-Wiener index...