Abstract: Flora composition and species diversity features of Castanopsis eyrei community at Tiantai Mountain of Zhejiang Province were analyzed.According to the statistics from 10 sample plots,there are 122 species(including varieties) of 93 genus belonging to 48 families of vascular plants.In terms of geographical composition of seed plant genus,most of them are distributed in the temperate zone.The species diversity of shrub layer is the highest,the tree layer the second,and the herb layer the lowest in the vertical structure of the community.In terms of the specific-abundance distribution,the tree layer,the shrub layer and the herb layer plants all conform to the logarithmic series distribution,which shows that there are more open species than the enriched species,and that the community evenness is relatively low.The diversity order of the family-genus-species in the community is:genus-species diversity>family-genus diversity>family-species diversity.

Key words: nitrogen, soil enzyme activity, desert steppe.