Evaluation and comparison of species diversity in Fagetum orientalis, Carpino-Fagetum orientalis and Querco-Carpinetum betulii communities (Case study :Namkhaneh and Gorazbon Districts-Noshahr)

Abstract

In this study the plant species diversity was compared among Fagetum orientalis,Carpino-Fagetum orientalis and Querco-Carpinetum betulii communities in Namkhaneh and Gorazbon districts. Floristic sampling was done by Braun-Blanquet scale on 69 releves which were selected in the different aspects of the mentioned comunities. 21،18 and 30 releves were sampled in the Fagetum orientalis, Carpino-Fagetum orientalis and Querco-Carpinetum betulii communities, respectively. The area of releves was identified 400 m2 according to the minimal area procedure. Species richness, Shannon and Simpson diversity indexes and Shannon evenness index were applied to evaluate species diversity of the different communities. For data analyzing, the different indexes's averages of releves in each community were calculated. Tukey test was used to test whether there were significant differences in the different indexes among the different communities. The results illustrated that the highest level of the plant species richness, diversity and evenness indexes belonged to Querco-Carpinetum betulii and the least level belonged to Fagetum orientalis. Carpino-Fagetumorientalis was located between two previous ones. The mean differences between both Carpino-Fagetumorientalis and Querco-Carpinetum betulii communities and Fagetum orientalis community were significant in all diversity indexes in 5% level. However, there were no significant differences in the different indexes between Carpino-Fagetum orientalis and Querco-Carpinetum betulii.

Keywords

• Caspian forests
• Plant community
• species richness
• species diversity
• Shannon index
• Simpson index