The increasing role of drought as an inciting factor of bark beetle outbreaks can cause large-scale transformation of Central European forests

作者：Agnish Kumar Das, Marco Baldo, Laura Dobor, Rupert Seidl, Werner Rammer, Roman Modlinger, Prosper Washaya, Katarína Merganičová, Tomáš Hlásny · 发表于：Landscape Ecology · 年份：2025 · DOI：10.1007/s10980-025-02125-w · 被引用次数：30 · 研究领域：Forest Insect Ecology and Management、Entomological Studies and Ecology、Fire effects on ecosystems

Context: Historically, large-scale outbreaks of the European spruce bark beetle were initiated mainly by windthrows. However, after 2018, a severe drought triggered the hitherto largest bark beetle outbreak observed in Europe, signalling a major shift in the disturbance regime. Objectives: Develop and test an approach that allows simulating this novel disturbance dynamics and evaluate landscape-scale compound impacts of wind- and drought-initiated outbreaks throughout the twenty-first century. Methods: We incorporated drought-initiated outbreaks into the forest landscape simulation model iLand, using critical values of vapour pressure deficit as the outbreak trigger. Forest management records and remote sensing-based disturbance maps were used to derive model parameters and evaluate simulated dynamics in a Central European forest landscape (41,000 hectares). The period 1961-2021 was used for model evaluation, and the years until 2100 for scenario analysis. Results: ncorporating drought as outbreak trigger led to a notable decoupling of wind and bark beetle disturbances, which have historically formed a typical disturbance cascade in European forests. While forest growing stock and species composition were resilient to a wind-dominated disturbance regime, this resilience diminished under the compounded impact of wind- and drought-triggered disturbances. The new disturbance regime caused a persistent decline in Norway spruce and resulted in an overall decrease in landscape-leve...