Determining the structural diversity of mixed oriental beech (Fagus orientalis L.) stands in Gorazbon district, Kheyrud forest

Document Type : Research article

Authors

1 Ph.D. Student, Department of Forestry and Forest Economics, Faculty of Natural Resources, University of Tehran, Karaj, Iran

2 Prof., Department of Forestry and Forest Economics, Faculty of Natural Resources, University of Tehran, Karaj, Iran

3 Associate Prof., Department of Forestry and Forest Economics, Faculty of Natural Resources, University of Tehran, Karaj, Iran

Abstract

Quantification of forest structure and its various components helps to better understand the forest ecosystem and supports its improved management. Here, the Gini index were used as a spatial distribution index for evaluating the structural diversity. The main objective was to analyse the stand structure and determine the necessary factors for the structural heterogeneity and  homogeneity. This study was conducted in compartments 305, 306, 309, 310 and 311 in Gorazbon district, Kheyrud forest by means of a full calipering method. Then Gini index was calculated and finally the Lorenz curve was derived by using frequencies of stems, diameter class, as well as cumulative relative frequencies of trees and their basal area. The results showed Gini index values of 39.5%, 66%, 44%, 82% and 74%  for compartments 305, 306, 309, 310 and 311, respectively. In addiiton, the diameter structure for 305 and 309 compartments was shown to be close to homogeneity, whereas it was close to medium for compartment 306 and close to heterogeneity for compartments 310 and 311. Finally the use of Gini index and Lorenz curve was concluded to he helpful in reclecting the near-real structural diversity in natural beech stands.

Keywords


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