The Study of Shrub Community Diversity in the Three Gorges Reservoir Area in China

According to the data of shrubs from 68 plots,there are 15 community types in the Three Gorges Reservoir area.As for the common shrubs,such as: Viburnum propinquum community, Cotinus coggygria community, Quercus fabri community,the richness index is relatively high both in shrub layer and in herb layer,the richness index in Myricaria laxiflora community, Distylium chinense community, Salix variegata community and S. variegata+M. laxiflora community is relatively low.The diversity index in V. propinquum community is relatively high both in shrub layer and in herb layer,but it is relatively low in Q. serrata var.brevipetiolata community, Coriaria nepalensis community and Vitex negundo community.The regularity of trend of community diversity along elvation has not been found,maybe human disturbance is one of the main reasons.