The Effect of Slope and Height above Sea Level on Tree Species Diversity in Arsbaran Forests

In order to protect and protect forests, these valuable resources, it is necessary and necessary to better understand the relationships between plants and the habitat conditions of these ecosystems and the biodiversity in them. Therefore, this research was conducted with the aim of investigating the effect of slope and altitude from sea level on biodiversity in Arasbaran forests.

30 sample plots of 1000 square meters (0.1 hectare) by dimensions 10 m×100m were surveyed in the study area. In the sample plots, the slope and height above sea level were recorded, and the slope was divided into three levels: <20%, 20-30% and >30%, and the altitude from sea level was also divided into two levels, <1700 m and >1700 m. In the sample plots, diameter at the breast height, type and abundance of species were recorded. The biodiversity indices computed were Simpson and Shannon-Wiener's, Margalf's and Menchnik's richness indices, and Pylo's and Hill's evenness indices. Biodiversity indices values ​​were computedby Past software.

According to the results, the highest frequency was related to the species of Quercus macranthera and Crataegus meyeri. The results showed that Hill's uniformity index decreases initially with increasing slope and then increases. Although the amount of other biodiversity indicators increases with the increase of the slope, statistically, the slope does not have a significant effect on these statistical indicators. Also, altitude above sea level did not have a significant effect on Species diversity indices.

The present research showed that the slope has a significant effect on Hill's evenness index and has no significant effect on other Species diversity indices of plant species. Also, the height above the sea level had no significant effect on the Species diversity of tree species of plant species. This importance can be due to the proximity to residential areas and destruction by villagers.