A Study on Species Diversity of Davidia involuarata Communities in Bainigang region of Wolong Nature Reserve

The species diversity of Davidia involuarata communities in Wolong Nature Reserve was invesitgated in terms of species diversity indices(Simpson index and Shannon index),species richness index and Pielous'evenness index.The results showed that the species diversity indices were different for different layers.In the communities the tree layer and the shrub layer had relatively high diversity in comparison with the herbaceous layer.Different layers affected each other obviously.The species and quantity of th communities decreased with the increase of elevation.The species diversity was highest at the range of an elevation from 1 690 m to 1 700 m.The species diversity of the whole communities was rich,but the stability was low.