پایش زی‌توده و سطح برگ درختان تحت زوال در شهرستان دنا و ارائه راهکارهای مدیریت بهینۀ این جنگل‌ها

نوع مقاله : مقاله ترویجی

نویسندگان

• یوسف عسکری ¹
• مهدی پورهاشمی ²

¹ استادیار پژوهش، بخش تحقیقات جنگلها، مراتع و آبخیزداری، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی استان کهگیلویه و بویراحمد، سازمان

² بخش تحقیقات جنگل، مؤسسه تحقیقات جنگل‌ها و مراتع کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، تهران، ایران.

چکیده

کلیدواژه‌ها

• بلوط ایرانی
• پایش
• خشکیدگی
• دانه‌زاد
• دشتک

موضوعات

• علوم مرتبط با جنگل در ناحیه رویشی زاگرس و مناطق خشک و نیمه خشک کشور

Monitoring of biomass and leaf area of declining trees in Dena County (in Iran) and providing optimal management strategies for these forests

Yousef Askari¹*, Mehdi Pourhashemi²

1^*- Assistant professor, research division of forest, rangeland and watershed, Kohgiluyeh and Boyerahmad Agriculture and Natural Resources Research and Education Center, AREEO, Yasouj, Iran. Email: y.askari@areeo.ac.ir  |  ORCID ID: 0000-0002-9468-150X  

2 - professor, Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, Iran

Received: 06/May/2026     Revised: 26/May/2026     Accepted: 06/June/2026

Abstract

Monitoring forest stands can provide valuable information to support forest management and decision-making. In this study, the progression of oak decline was monitored over a four-year period in the Dashtak area, located on the northern slopes of Dena County, Kohgiluyeh and Boyer-Ahmad Province, southwestern Iran. Because oak decline is often manifested through changes in crown condition and leaf characteristics, tree decline was assessed based on crown symptoms and selected leaf traits. For this purpose, a permanent one-hectare sample plot was established, and changes in tree decline status were recorded and evaluated during 2019–2022 using five decline classes: healthy trees, trees with crown dieback, trees with less than 50% crown dieback, trees with 50–90% crown dieback, and completely dead trees. To assess variations in leaf characteristics, five trees were sampled within each decline class, with sampling conducted across diameter classes and according to tree regeneration origin. The results showed that mean leaf area was greater in seed-origin trees than in coppice-origin trees. In addition, the mean biomass of 20 leaves ranged from 8 to 13 g across the different decline classes and monitoring years. Leaf-area assessment further indicated that leaf size decreased with increasing decline severity; trees exhibiting greater levels of crown dieback had smaller leaves, whereas healthy trees had larger leaves. Based on the findings of this study, appropriate thinning of dead and declining branches, as well as systematic thinning of clumped tree groups, is recommended to reduce decline severity and enhance the growth of remaining trees. Furthermore, the expansion of protected areas, construction of contour bunds to improve the retention and storage of precipitation, and targeted water supply to critical decline hotspots may be considered as complementary measures for the restoration of degraded and declining oak forests.

Key words: Dashtak, dieback, high forest, monitoring, Persian oak.

Citation:

Askari, Y., Pourhashemi, M. 2026. Monitoring of biomass and leaf area of declining trees in Dena County (in Iran) and providing optimal management strategies for these forests. Zagros Ecosystem and Sustainable Development, 1(2): 17-23.

DOI: 10.22034/ZAGROS.2026.372726.1008

URL: https://zagros.areeo.ac.ir/article_136042.html

 عسکری، ی.، پورهاشمی، م. ۱۴۰۵. پایش زیست‌توده و سطح برگ درختان تحت زوال در شهرستان دنا و ارائه راهکارهای مدیریت بهینۀ این جنگل‌ها. زیست‌بوم و توسعه پایدار زاگرس، 1(2): 23-17.