Evaluation Accuracy of Nearest Neighbor Sampling Method in Zagross Forests

Collection of appropriate qualitative and quantitative data is necessary for proper management and planning. Used the suitable inventory methods is necessary and accuracy of sampling methods dependent the inventory net and number of sample point. Nearest neighbor sampling method is a one of distance methods and calculated by three equations (Byth and Riple, 1980; Cotam and Curtis, 1956 and Cotam and Curtis, 1956). The 53 hectare of the study area was selected and perfect inventory. To study of nearest neighbor sampling method used the systematic-random methods in the 100*150 meter net and recorded the location (X, Y) of all trees and by nearest neighbor sampling method in the 30 to 40 samples evaluated the accuracy of this method. Results showed that the three formulas in this study not have accuracy for study of density (N/ha), but suitable to study of spatial pattern. The quantity of Johnson & Zimmer index is a 5.522 and showed that a clumped pattern for trees in forest reserve. Overall results showed that the nearest neighbor sampling method and Byth and Riple (1980) equation are a suitable method to study of tree spatial pattern in Zagros forest