Analysis and experimentation on ecosystems

The determination of ecosystem carbon balances is a major issue in environmental research. Forest inventories and – more recently – Eddy covariance measurements have been set up to guide sustainability assessments as well as carbon accounting. A differentiation between ecosystem compartments of carbon such as soil and vegetation, or above- and belowground storages nevertheless requires further empirical assumptions or model simulations. However, models to estimate carbon balances often do not account for carbon export by management and the direct and indirect impacts of forest management. To overcome this obstacle, we complemented a physiologically based process model (MoBiLE-PSIM) with routines for dimensional tree growth and mortality and evaluated the full model with measurements of water availability, primary production, respiration fluxes and forest development (tree dimensions and numbers per hectare).