Study on species diversity of different forest types and affecting factors

By using the indexes of richness,diversity and evenness,the species diversity of shrub and herb layers of different forest types in Wuling Mountain is researched in this paper,and stepwise regression model is used to find major factors affecting species diversity.The results show that the species diversity of shrub and herb layers of different forest types from high to low is coniferous and broad-leaved mixed forestdeciduous broad-leaved forest coniferous forest;Most forest types,the diversity and richness indexes of herb layer are higher than those of shrub layer,while the evenness index is opposite.The major factors affecting species diversity of shrub layer include age,canopy density and slope.The major factors affecting species diversity of herb layer include stand density, canopy density and soil depth.