Future protective forests: a regional forecast on potential natural conditions of woody species impacted by climate change along the Austrian railway corridor

Abstract

Introduction: Railway corridors, as linear landscape structures, are highly exposed to natural hazards. In alpine regions intact protective forests form a key basis for safeguard ing the route network by complementing technical protection mea- sures through forest-related ecosystem services. From a long-term perspective, these benefits are only generated by resilient and vital forest stands. To maintain sustainable services and benefits under climate change, an understanding of the biological system and its future developments is essential. Difficulties lie in long reaction times of forest stands to management actions and a broad range of species, that need to be considered. Methods: The method used in this study focuses on the extrapolation of potential natural stands based on basic climate parameters by developing a two-dimen- sional climatic space, describing natural stands for 46 species in all 26 operational units of the Austrian railway corridor. First, we analyzed the current distribution of woody plant species using a climate-envelope modeling approach. Secondly climatic conditions of the Austrian railway network were evaluated and mod- elled for future climate change scenarios. In the synthesis of steps one and two, potential natural stands were detected, quantified, contextualized and compared to the reference period 1961–2020. Results: Several promising species were detected for future climate scenarios and European wide trends were confirmed on the regional scale. Especially Castanea sativa, Ulmus minor, and Sorbus torminalis can help generating vital stands that can deliver the protective functions we are aiming for. Discussion: The results mark an initial step toward climate-change-adapted pro- tective forest management by detecting changes in natural site conditions and predicting vulnerable areas along the Austrian railway corridor, offering a man- agement tool for infrastructure operators to guide future species selection and assess risks to protective forest functions.