Abstract ID: 3.13968 | Accepted as Poster | Poster | TBA | TBA

Drought and late frost events are major disturbances within forest ecosystems. Under a climate change regime, their likelihood, frequency and severity are expected to change, which makes it important to investigate their impact on trees. In a potted experiment, we simulated late frost and drought regimes, putting the trees in a cooling truck to simulate a frost night after bud burst and by controlling the watering during drought season. Overall, the experimental design had five late frost levels and eight drought levels with double control groups, which led to 70 groups and 2250 pots in total. 33 forestry-relevant species were tested within the experiment with 10 species relevant for the northern calcareous alps. Goal of this gradient experiment was to examine the threshold at which the disturbances cause irreversible harm to the trees. Both disturbances were analyzed singular, but also the interaction between both. This experiment showed differences in responding to drought and late frost between multiple tree species. For example, early budding trees are more late frost tolerant, whereas the drought tolerance depend more on the origin of the tree. The measurements also indicates that not the drought, but the heat was the cause of leaf damage for the trees.