湖南省南岳原生性森林群落的研究 Ⅲ.长叶石栎林

湖南省南岳原生性森林群落长叶石栎林是一种尚未报道过的群落新类型，即长叶石栎＋多脉青冈－尾叶山茶－求米草群丛（Association of Lithocarpus henryi Cyclobalanopsis multinervis-Camellia caudata-Oplismenus undulatifolius），属于典型的常绿落叶阔叶林。该群落属的区系成分主要是北温带和泛热带2种分布区类型，其中温带性质成分占主体；而种的区系成分主要是华夏、东亚、华东－华中3种分布式样，具有华东－华中区系的过渡交替色彩。群落可以明显分为乔木层、灌木层和草本层，其中乔木层又可分为2个亚层，该群落能稳定相当一段时间，更新演替过程中虽然会保持常绿落叶阔叶林性质，但其优势种可能被尾叶山茶、多脉青冈等树种取代。该群落物种多样性水平接近季雨林与稀树草原之间的水平；Shannon-Weaver、Brillouin和McIntosh等3个多样性指数及其对应的均匀度指数可能适合研究群落物种多样性；在研究群落物种多样性时必须要多用一些公式进行测定才可能避免出现错误的结果。不同的物种相对多度分布格局模型在拟合群落不同层次时其结果并不一致。

Study on Original Forest Community in Nanyue of Hunan Province

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.