Study on Original Forest Community in Nanyue of Hunan Province Ⅲ.Lithocarpus henryi Forest

According to the investigation and research of the Lithocarpus henryi forest in Nanyue,Hunan Province,this community is a new type that it hasn't been reported,it can be called Association of Lithocarpus henryi+Cyclobalanopsis multinervis-Camellia caudata-Oplismenus undulatifolius and it is belonged to the evergreen and deciduous broad-leaved mixed forest.There are 73 species,64 genera and 44 families belonging to the vascular plant in the community.The temperate elements of the floristic genera in the community occupies 53.45% of the total,but the tropical one 46.55%.The floristic elements of species in the community are mainly Cathaysian,East Asia and East China-Central China which occupy 25.35%,22.53% and 12.68% of the total respectively.It has very obvious that it cross between the floristic elements of East China and Central China of the species of the community.The wood plants in the community occupy 80.39% of the total,but the herb 19.61%.The community can be divided the arbor layer that it can be divided 2 sublayers,shrub la- yer and herb layer.It still keeps the evergreen and deciduous broad-leaved mixed forest,but its dominant species i.e.Lithocarpus henryi will probably bereplaced by Camellia caudata or Cyclobalanopsis multivervis and so on.The results show that the plant species diversity of the community is high,and that its value approaches the species diversity between Seasonal rain forest and Savannas,and that the indices of Shannon-Weaver,Brillouin,McIntosh and their Evenness can be suited for studying the plant species diversity of the community,and that the values have not the obvious law by using different measurement degree to calculate the indices of species diversity.We choose the Geometric series distribution,Broken-stick,Log series distribution and Log normal distribution to study the distributional pattern of species relative abundance of the community,the results show that the Geometric series distributional model is suitable for imitating the arbor and herb layers,but not for the shrub layer,and that Broken-stick model is only suitable for imitating the arbor layer,and that Abundance-Frequency model of Broken-stick is suitable for imitating the herb layer,and that Log series distributional model is completely suitable for imita- ting any layer,and that Log normal distributional model is only suitable for imitating the arbor layer.