Iranian Journal of Forest

Iranian Journal of Forest

The structure of Juniper forest stands (Juniperus excelsa M. Bieb.) in protected and unprotected plots of North Khorasan province (case study: Saluk region)

Document Type : Research Paper

Authors
1 Associate Prof., Research institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, Iran.
2 Prof., Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
3 Research Expert, Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
4 Assistant Prof., Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran.
Abstract
Introduction: Understanding the structure of forest stands, particularly in Irano-Turanian regions, is essential for effective management and conservation efforts in semi-arid and arid areas. A thorough understanding of forest structure, including species distribution, tree size, and spatial patterns, enables more accurate assessments of ecological status, predictions of forest responses to environmental changes, and ultimately, the adoption of more efficient management decisions. This study aimed to investigate the structure of juniper stands in two one-hectare plots (protected and unprotected) in the Saluk region of North Khorasan province, Iran.
Materials and Methods: For a comprehensive analysis of the forest stand structure, all trees in each one-hectare plot were assessed. Quantitative parameters such as DBH, total height, and crown diameter in two perpendicular directions were measured. The spatial distribution of trees within each plot was determined by measuring the distance and azimuth of each tree. Statistical analyses were then performed to compare the structural characteristics and spatial patterns between the two plots.
Results: The results showed that the spatial distribution of juniper trees in the unprotected plot was random. While in the protected plot, this pattern changed to a regular one at close distances and to a random one and finally to a clustered pattern as the distance increased. The number of juniper trees per hectare was 84 in the protected plot compared to 31 in the unprotected one. There was no significant difference between the average crown area (12.2 ± 1.1 vs. 13.5 ± 2.8 m2), DBH (16.9 ± 0.7 vs. 16.6 ± 1.4 cm) and height (3.9±0.5 vs. 3.5±0.1m) of juniper trees in protected and unprotected plots. The average crown area of all species in the protected plot (9.5±0.8 m2) showed a significant difference from the unprotected one (6.4±1.0 m2).
Conclusion: Considering the situation of crown cover percentage and the spatial distribution pattern of all trees and also juniper trees in the investigated plots as well as the density of trees which is in the low range of the density of juniper stands reported by other researchers, it is necessary to apply restoration management, development and conservation in these forests.
 
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Volume 17, Issue 1 - Serial Number 1
Summer 2025
Pages 145-158

  • Receive Date 07 September 2024
  • Revise Date 28 September 2024
  • Accept Date 14 November 2024