Stable isotopes are a universal tool for studying ecosystem processes and fluxes in forests. The isotope group aims to promote the application of this innovative method, coordinate research projects and provide measurement platforms. Current research projects include the investigation of the carbon balance in a dry-stressed pine forest in the Valais and climate reconstructions using isotope variations in tree-rings. In the experiment in the Valais, canopies of adult pines were temporarily wrapped in foil and marked with 13CO2. The transport of the assimilated, labelled carbon could then be tracked and quantified in different ecosystem compartments.
In addition to the WSL, other institutions of the ETH Domain as well as the universities are active in this field. Workshops are intended to promote the exchange of experiences and collaboration. A first meeting took place on 24 May 2018 at the WSL and showed the wide range of activities with stable isotopes of research groups active in Switzerland.