Researchers from the Swiss Federal Institute for Forest, Snow, and Landscape Research (WSL) have studied how trees react to extreme temperatures. Using a high-tech experimental setup called XiBox, scientists were able to expose plants to different environmental conditions and monitor their behavior through gas exchange and isotope measurements. They examined the following tree species: beech (Fagus sylvatica), spruce (Picea abies), sessile oak (Quercus petraea) and small-leaved lime (Tilia cordata).
They found that at temperatures above 30°C, trees lose more water but absorb less CO₂, even when CO₂ levels are sufficient. This reduction in CO₂ uptake is due to biochemical limitations affecting photosynthesis efficiency. All the trees reacted in the same way. There were no significant differences between species.
Such simulations are important for better understanding and predicting the capacity of plants and their functions to adapt to new climatic conditions and the resulting rise in temperatures.