Quantitative Analysis of Forest Structure at Growing Up Volume Stage in the Evaluation of Natural Beech Stands (Case Study: Kheyroud Forest)

The structure of forest stands changes over time and under the influence of local disturbances, these changes are referred as the dynamics of forest stands. Changes in the structure of forest stands result in the formation of development phases. The purpose of this study was to identify the structural characteristics of natural beech forests during the stage of growing up volume in the Kheyroud forest. For this purpose, three one-hectare sample plots with structural features of growing up volume stage were selected and the location, diameter and height of all trees within each sample plot with DBH N 7.5 cm were measured. The structural properties of this stage were investigated using a set of indices based on the nearest neighbors. Based on the results, the mean values of uniform angles and Clark and Evans indices were 0.49 and 0.96, respectively, which indicated a random clumped spatial pattern of trees at this stage. The results of the mingling index showed that the tendency of beech trees to mix with other species was low. The results of diameter differentiation index indicated a clear difference and height differentiation index showed a moderate difference in dimensions of trees with each other. In general, using the nearest neighbor indices showed that these indices have a high ability to detect the differentiation of forest stands in the growing up volume stage and thus are useful tools for forest management.