Modelling land surface fluxes of CO2 in response to climate change and nitrogen deposition

Climate change, land use variations, and impacts of atmospheric nitrogen (N) deposition represent uncertainties for the prediction of future greenhouse gas exchange between land surfaces and the atmosphere as the mechanisms describing nutritional effects are not well developed in climate and ecosystems models. Recent research indicate the need for incorporating the ammonia (NH3) compensation point in atmospheric N deposition models to quantify the N budget for vegetative surfaces. This poster presents a PhD project within ECOCLIM of incorporating the NH3 compensation point in a coupled photosynthesis-stomatal conductance model to allow more realistic estimation of the predictions NH3 deposition rates and CO2 fluxes of terrestrial ecosystems. Such an integrated model system will improve the understanding of processes responsible for net sources and sinks of CO2 enabling us to predict important climate feedback mechanisms of CO2 between changes in management, land use practise, and climate change.