The comparison of pure beech stands using SCI index in the Hyrcanian forests of Iran (Mazandaran province)

Document Type : Research Paper


1 Corresponding author, Associate Prof., Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, Iran

2 Senior research expert, Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, Iran



Comprehensive description and quantification of stand structure are needed for managing or maintaining forests as complex systems. The Structural Complexity Index (SCI) is a suitable criterion for quantifying the structural heterogeneity of forest stands, which can be used to compare the structural heterogeneity of stands. In this study, we used this index to quantify the structural heterogeneity of three pure beech stands in the Hyrcanian forests of Iran. Forest inventory was performed using a fixed grid of 150×200 m dimension and sample plots of 1000 m2 in watersheds of 46, 49, and 66a in Mazandaran province, where two stands were managed, and one was unmanaged. Using the spatial coordinates and diameters of trees in 90 measured sample plots in the three stands, we calculated the SCI index for each sample plot as well as its average for each stand. The results showed that the rate of this index in these three stands fluctuated between 2.7 to 11.7. However, its average in each region is approximately 6, without any statistically significant difference between them. The results also showed that the amount of this index was positively correlated with the variables of basal area and standing volume of the stands. The SCI index in protected forests with high ecological quality can be used as a reference or baseline for assessing the suitability of management techniques to maintain or enhance the structural heterogeneity of stands.


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Volume 14, Issue 4
February 2023
Pages 445-456
  • Receive Date: 06 February 2022
  • Revise Date: 20 April 2022
  • Accept Date: 13 May 2022
  • First Publish Date: 20 February 2023