Investigating the Structure of Beech Stands in the Gap Making Phase (Case study: Asalem Forests, Guilan)

Forest structure consider the spatial arrangement of trees characteristics such as age, size, species, gender and so on is.This study aimed to investigate the structural diversity of three one-hectare stands in the gap making phase, were studied. For this purpose, three sample plots with a one hectare area were selected in Asalem beech stands which belonged to the structural features of the gap making phase and studied. In each plot 30×30 m network were established. After implementing the network, the quantitative and qualitative features of the two beech trees at the closest distance to the intersection of the network as the references trees number one and two with three neighboring trees belonging to each of the references trees located at the nearest distance, was taken. The distance between the references trees and neighbors, as well as the distance between the neighboring trees, were measured relative to each other, and based on the Pythagorean trigonometric relationships, the angle between the references trees and the neighbors were measured. According to the results of this study, the average of species mingling, diameter differenation, height differenation and neighbor distance is 0.23, 0.43, 0.87 and 4.87 meters, respectively. By using of data from structure of intact stands, not only the current structure of various species can be quantified but also, their evolutionary process as well as the results of the forest management activities can be assessed.