Investigation effect of grazing intensities on functional diversity and species diversity indices in the rangeland Bolban Abad, Kurdistan province

This study was carried out in Bolban Abad, Kurdistan province, Iran, in order to investigate the changes in species diversity and functional diversity of vegetation under different grazing intensities. In this study, the data of three sites with different grazing intensity (low, moderate and heavy) were collected. Indices of species diversity including: richness (S), Shannon (H), evenness (E) and Simpson (D) and the functional diversity index (convex hull hyper-volume (CHull), Functional Richness (FRic), Functional Evenness (FEve), Functional divergence (FDive) and index Rao (Rao) were calculated for all sites. FD package and generalized canonical discriminant analysis (gCCA) were used in R 3.1.1to calculate these indices and determine the effect of grazing intensity on diversity indices. In addition, Duncan's test was used to compare the means of grazing intensities. Results showed that the species diversity indices, species richness index (S) and Shannon (H) were reduced by increasing grazing intensity. According to the results of generalized canonical discriminant analysis, species richness showed little change in response to grazing and CHull index showed an increase under grazing. Also, species functional traits were decreased with increasing of grazing intensity.