Strategic Research Journal of Agricultural Sciences and Natural Resources

Strategic Research Journal of Agricultural Sciences and Natural Resources

Evaluation of the Canopy Cover Role in the Restoration of Zagros Oak Forests on the Basis of Natural Regeneration Establishment Pattern

Document Type : Original Article

Author
Ahmad Hosseini
Associate Prof., Ilam Agricultural and Natural Resources Research and Education Center, AREEO, Ilam, Iran
10.22047/srjasnr.2026.574711.1156
Abstract
Natural regeneration is one of the fundamental processes contributing to the sustainability and continuity of forest ecosystems and plays an important role in forest renewal and maintenance of forest structure. During recent decades, Zagros oak forests have experienced a severe decline in natural regeneration due to human pressures, climate change, and reduction of canopy cover, resulting in weakened regeneration capacity. The objective of this study was to analyze the spatial pattern of natural regeneration and evaluate the role of ecological factors, particularly canopy cover, in seedling establishment success. In addition, the applicability of these patterns for forest restoration programs was investigated. This study was conducted as part of a five-year research project in the Dalab forests of Ilam province, Iran. The research was carried out from 2015 to 2019 in eight sites located under three topographic conditions. In the first stage, the establishment pattern of natural regeneration of woody species was examined through field surveys. In the second stage, seeds of Persian oak (Quercus brantii Lindl.), wild pistachio (Pistacia atlantica Desf.), maple (Acer monspessulanum L. subsp. cinerascens), and wild almond (Amygdalus scoparia Spach.) were sown in different microhabitats according to the identified natural regeneration pattern. The results showed that the highest density of natural regeneration and planted seedlings occurred beneath tree canopies and on north-facing slopes at elevations below 1500 m above sea level. Seedling establishment success was considerably lower in open areas without canopy cover than in other establishment sites. The similarity between natural and artificial regeneration patterns indicated that restoration measures based on natural ecological processes and seed placement in protected microhabitats can improve restoration success. Overall, the findings emphasize the importance of canopy-based restoration approaches and spatial heterogeneity in the sustainable management of Zagros forests. Therefore, protection of existing canopy cover, control of livestock grazing, and targeted direct seeding beneath tree canopies are recommended as key strategies for the restoration of Zagros oak forests.
Keywords
Direct seeding
Forest restoration
Microhabitat
Natural regeneration
Persian oak
Zagros forests
Subjects
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Strategic Research Journal of Agricultural Sciences and Natural Resources
Volume 11, Issue 2
October 2026
Pages 239-250