Study on species composition and species diversity of Castanopsis secondary forest in Jiangle Forest Farm

By using the survey data of permanent plots in Fujian Jiangle Farm,the species composition and species diversity were investigated,so as to provide certain reference basis for the study of Castanopsis secondary forests.The sample plots' species diversity values for tree layer,shrub layer and herb layers were studied by selecting Shannon-Wiener index,Simpson's diversity index,Dominance index,Species richness and Evenness index as the diversity measure indexes,and according to the tree layer species diversity indexes of the sample plots,the Castanopsis secondary forests were clustered and analyzed,thus the sample plot types were divided.The results show as follows:(1) Species composition was rich,there were 76 kinds of species in tree layer,77 kinds in shrub layer,22 kinds in herb layer;(2) All diversity index differences about tree layer,shrub layer and herb layer of the sample plots were big,while the evenness and dominance indexes' differences were not very big,the species distributions were relatively uniform;(3) Shannon-Wiener index,Simpson's diversity index,Species richness and Evenness index all ranked from bi g to small as follows:tree layer shrub layer herb layer,and the order of the Dominance index was opposite;(4) Castanopsis secondary forests were divided into three types,of them type-I included plot-1,plot-2,and plot-11,type-Ⅱ included plot-5,plot-6,plot-10,plot-12,plot-13 and plot-14,and type-Ⅲ included plot-9,plot-17 and plot-18.Shannon-Wiener index,Simpson's diversity index,Species richness and Evenness index sequenced from big to small as follows:type Ⅲ type Ⅱ type Ⅰ,the order of the Dominance index was opposite.Species composition of Castanopsis secondary forests in this area were rich,There was a big difference about species diversity in each layer,and there was similar species diversity in the same type,it shows that the degree of interference was similar.