Comparison of circular plot and transect sampling methods in the Zagros Oak Forests (Case study: Educational and research forest of Razi University, Kermanshah province)

In order to determine the suitable sampling method for estimating of stem number per ha and percentage of canopy cover in the protective western oak forests of Iran (Zagros), a survey was carried out in Kermanshah province. For this purpose and based on cost and precision (E%2 × T) criterion, two sampling 1- transect by distance measurement between trees and 2- circular plot with area of 1000m2, were carried out in 50 ha area of the educational and research forest of Razi University, which was already surveyed by 100% inventory. For each sampling method based on systematic-random sampling design with 100m×100m dimensions, 50 samples were selected. In each sample plot and transect, the number of trees and some characteristics of trees such as number of coppice shoots, the least and highest crown diameter were recorded and measured. Results showed that the more suitable method for these forests in west of Iran is the circular sample plot with 1000m2 area.