Comparative analysis of oak tree health indicators in the Northern Zagros

Document Type : Scientific Letters

Authors

1 Assistant Professor, Forest Research Department, National Forest and Rangeland Research Institute, Agricultural Research, Education and Extension Organization, Tehran, Iran,

2 Ph.D. Student in Environment, Malayer University

3 Associate Professor, Natural Resources Research Department, Chahar Mahal and Bakhtiari Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization, Shahrekord, Iran

10.22092/irn.2025.369167.1645

Abstract

The gradual dieback of oak trees represents one of the major environmental challenges confronting the Zagros forest ecosystems, posing a serious threat to the sustainability of biodiversity, water resources, and local communities' livelihoods. This study aimed to evaluate the health status and ecological quality of oak tree bases in two areas with differing ecological conditions in Marivan County over four years (2019–2022). To achieve this objective, the decline in tree vigor and the progression of wilting symptoms at each location were monitored annually. The assessment included classifying trees into four crown health categories and analyzing differences among the categories using nonparametric statistical tests. The results indicated that species composition, crown condition, and certain ecological characteristics—such as stand density—play significant roles in explaining the variation observed in oak health levels. According to the findings, the site characterized by higher species diversity exhibited more stable vitality patterns throughout the study period. These results highlight the importance of long-term monitoring of qualitative indicators and the need to understand ecosystem degradation trends, thereby providing a foundation for developing effective management strategies aimed at conserving the native woodlands of the Zagros region.

Keywords

References

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Iran Nature
Volume 10, Issue 4 - Serial Number 53
November and December 2025
Pages 39-44

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