Evaluation of Beta diversity indices in identifying vegetation differences of Buxus hyrcana plant communities in the Hyrcanian Forests

The Increase in studies of beta diversity has led to several measures and methods. The variety of theses indicators cause their use in confusion. The aim of this study was to evaluate and determine the relationships between 18 different beta diversity indices based on presence and absense data. For this purpose, Buxus hyrcana database in Golestan and Mazandaran provinces was used. Clustering results showed that these 18 indices classified into 4 distinct groups with similar performance. Evaluation of clustering results by Detrended correspondence analysis (DCA) analysis showed that the indices of the four groups of cluster analysis can be separated into three distinct groups. From basis of combined results of discriminant analysis and Braun-Blanquet method, three vegetation units were recognized, which had 64.1 percent coincide with phytosoicilogical plant communities in Braun- Blanquet method. Also, among of 18 beta diversity indices included in the discriminant analysis, only Bm, Bc, B-2, Brlb, Bco, BI and Be were added in three functions. Among these 7 indices, them, Bm, Bc, BI and Be had a high canonical correlation with the three discriminant analysis functions. totally, the results of this study showed that many beta diversity indices based on presence and absense data have similar performance, and the numerical values of beta biodiversity indices are a good criterion for identifying Buxus hyrcana plant communities, provided that species turnover in these plant communities being high.