Characteristics and species diversity of Juglans cathayensis community in Guizhou

Field surveys were conducted on Juglans cathayensis community in Guizhou，by using methods of routine investgation in the feature and diversity of community. The results showed the J. cathayensis community consisted of 56 species in 56 genera，36 families. The vertical structure was very obvious，which can be divided into canopy，shrub and herb layer，and J. cathayensis was the only dominant species of the canopy. The appearances was determined mainly by the phanerophuta and hemicryptophyta plant. The important value of J. cathayensis was 94.36 in canopy layer，which was dominant position，the second was Cornus macrophylla，those important value was 77.51，the third was Chimonobambusa quadrangulari，its important value was 77.51. The radial structure showed a discontinuous distribution，which was concentrated in the small diameter class，it was a stable population. The species diversity of this community was relatively low，the species diversity was 36， the Shannon Wiener index was 3.356，the Simpson index was 1.263，the Pielous index was 0.364. The Shannon- Wiener and Pielous index of herb were 3.145，0.513，which were the largest，the most abundant species and diversity appeared in herb layer.