Document Type : Research Paper

Authors

• Mahmoud Bayat ¹
• Majid Hassani ²

¹ Assistant Prof., Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran.

² Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran.

Abstract

Biodiversity analysis in northern forests of Iran is very important due to its importance as one of the most valuable forest ecosystems in the country. In this study, the indexes of Margaleph and Menhink, Simson, Shannon Wiener and Pilo, Hip in two forest areas of 10 Chafrood and 7 Nav Asalem of Gilan province were used. 31 and 30 0.1 hectare plots in a 150 * 200 m survey network in 10 Chafroud and 7 nav forests, respectively, were permanently taken and measured and the indices mentioned in each sample plots were estimated. One-way ANOVA and Duncan analyzes were used to compare the two regions in terms of biodiversity indices. Then, altitude, slope and slope direction factors were determined in two regions and their effects on biodiversity indices were evaluated by correlation coefficients and analysis of variance. The results showed that the diversity indices of Simpson, Shannon Wiener, Pilo and Hip homogeneity indices were significantly different at 95% probability level. Margaluff and Mannhink richness did not show significant differences between the two regions and the 10 Chafrood region, was higher than all 7 Nav region, in all indices. The altitude factor had a significant negative correlation with almost all biodiversity indices. Slope and geographic direction were only significantly correlated with some indices. Obviously, it is necessary to study the different forest areas and other important factors affecting the biodiversity of forest ecosystems to obtain reliable results.

Keywords

• Biodiversity Index
• Analysis of Variance
• Asalem
• Topographic Factors
• Gilan