The vulnerability of Mediterranean forests to extreme heat and drought events: the case of Holm oak (Quercus ilex L.) dieback in Italy

作者：Salvatore Seddaiu, P. A. Ruiu, Giovanni Piras, Bruno Scanu, Giannina Satta, Andrea Lentini, Donato Salvatore La Mela Veca, A. Sidoti, M Castellaneta, Michele Colangelo, Nicola Moretti, Francesco Ripullone, Eustachio Tarasco, E. Gravano, EM Mocci, AG Delle Donne, Giovanni Iacopetti, Davide Bettini, Filippo Bussotti, Martina Pollastrini · 发表于：Forest - Rivista di Selvicoltura ed Ecologia Forestale · 年份：2025 · DOI：10.3832/efor4934-022 · 被引用次数：2 · 研究领域：Plant Water Relations and Carbon Dynamics、Horticultural and Viticultural Research、Tree Root and Stability Studies

Extreme heat waves coupled with severe drought episodes are increasing in frequency in the Mediterranean region. Such climatic events pose significant threats to evergreen sclerophyllous vegetation, despite their inherent resistance and adaptation to drought conditions. Over recent decades, several cases of dieback affecting Quercus ilex, Quercus suber, and other evergreen shrubs have been reported across the Mediterranean basin. In Italy, the first reports of Q. ilex dieback due to climatic events date back to 2012 in Tuscany, and with more extensive impacts observed following the extreme drought of 2017. During the summer of 2024, widespread dieback phenomena were reported across Southern Italian regions, including Apulia, Basilicata, and the islands of Sardinia and Sicily. The symptoms were consistent and recurrent in all the affected areas, characterized by partial or total foliar browning, followed by wilting and branch dieback. Notably, resprouting from dormant buds was observed in affected branches and leaves in the following rainy season. Affected areas showed ongoing symptoms of oak decline, often associated with the presence of Phytophthora spp. and other opportunistic pathogens, suggesting a complex interaction between biotic and abiotic stressors. This study aims to document and analyze the most relevant cases of Q. ilex dieback occurring in central and southern Italy, using also data collected through the SilvaCuore web application. The phenomenon of dieback and ...