Turgor loss point explains climate-driven growth reductions in trees in Central Europe

As climate change thrives, and the frequency of intense droughts is affecting many forested regions, a mechanistic understanding of the factors conferring drought tolerance in trees is increasingly important. However, studies linking the observed growth reduction to mechanistic traits are still rare. We compared the median growth anomalies of 16 native tree species, gathered across a network of study plots in Bavaria, with the mean species-specific turgor loss point (pi tlp) measured at five locations in Central Europe pi(tlp) explained 37% of the growth anomalies observed in response to the intense droughts between 2018 and 2020 compared to the pre-drought period between 2006 and 2017 across sites. pi(tlp) constitutes an important leaf drought tolerance trait and influences the growth response of native tree species during extraordinary dry periods. As climate change-induced droughts intensify, tree species with drought-tolerant leaves will be less vulnerable to growth reductions. pi tlp provides a useful indicator for selecting tree species to adapt forest management systems to climate change.