Oak Trees Deterioration in Kurdistan Forests: Assessing Climate Change Effects with Fungal Infestation Using Multi-Analytical Methods: Oak Trees Deterioration in Kurdistan Forests

Khalat Fadhil Mohammed; Kamal Kolo

doi:10.63841/iue31642

Authors

Khalat Fadhil Mohammed 1Petroleum Geoscience Department, Faculty of Science, Soran, Kurdistan Region, IRAQ Author https://orcid.org/0009-0000-3510-8132
Prof. Dr. Kamal Kolo 2Scientific Research Center (SRC), Soran University, Soran, Kurdistan Region, IRAQ Author https://orcid.org/0000-0002-2950-2341

DOI:

https://doi.org/10.63841/iue31642

Abstract

The observed rapid pace of climate change in Iraq, as well as worldwide, coupled with anthropogenic interventions such as agricultural and urban expansion, is threatening the integrity and sustainability of natural forests. In the Kurdistan Region of Iraq, oak forests constituting nearly 90% of the region’s forest cover are exhibiting alarming signs of decline, particularly in the Barzan area, where heartwood decay and hollowing of trunks have become prevalent across young and old trees. This study provides the first detailed multiparametric investigation into oak tree decline in Barzan forests, integrating field observations, SEM-EDX, XRD, and FTIR spectroscopy. FTIR-based indices revealed significant degradation of cellulose and hemicellulose, with lignin-to-cellulose ratios exceeding 1.0 in decayed samples. SEM-EDX analysis confirmed extensive fungal hyphal colonization and localized calcium oxalate biomineralization within heartwood tissues. XRD results showed a progressive decline in cellulose crystallinity index (from 51% in healthy to 35% in severely decayed wood). Tree ring width chronology (1928–2023) showed a declining growth trend, strongly correlating with rising temperatures and declining precipitation in the region. These findings suggest climate-driven fungal decay as the primary mechanism of oak forest deterioration in Kurdistan.

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Author Biographies

Khalat Fadhil Mohammed, 1Petroleum Geoscience Department, Faculty of Science, Soran, Kurdistan Region, IRAQ

Khalat Fadhil Mohammed is a master student at the Faculty of Science, Department of Petroleum Geoscience, Soran University. She obtained her B.Sc. degree in Petroleum Geoscience in 2019. Her research interests include paleoclimate reconstruction and petroleum geology. She has published one paper in the field of petroleum geology as a co-author.
Prof. Dr. Kamal Kolo, 2Scientific Research Center (SRC), Soran University, Soran, Kurdistan Region, IRAQ

Kamal Kolo is a Professor emeritus at the Scientific Research Center/ Soran University. He got his B.Sc. Degree in 1976, and M.Sc. degree in 1982. He holds two PhD degrees in Petroleum Geosciences (1985) and in Geobiology (2009). His research interests are in Petroleum Geosciences, Geobiology, Microbe-minerals Interaction, Biomineralizations, and Paleoclimate Reconstruction. Prof. Kamal is a member of Geological Society of Belgium and attended over 30 national and international conferences and authored and co-authored 8 books and 119 papers:

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Oak Trees Deterioration in Kurdistan Forests: Assessing Climate Change Effects with Fungal Infestation Using Multi-Analytical Methods