The Braunschweig carbon project - atmospheric flux monitoring and free aircarbon dioxide enrichment

With respect to the predicted climate change it has become evident that the role of terrestrial ecosystems in the global carbon turnover is not yet fu lly understood. This is also true for carbon fluxes in agricultural ecosyst ems. As increasing atmospheric CO2 concentrations will directly affect plan t photosynthesis, plant biomass production and plant water relations, it is of particular importance to predict the dynamics of carbon fluxes between the atmosphere and agricultural canopies and the related consequences for a groecosystems under future atmospheric CO2 conditions. There are hardly any experimental approaches under real field conditions in crop rotation syste ms to simulate future CO2 scenarios. The Braunschweig carbon project is a c ombination of micrometeorological flux measurements of atmospheric trace ga ses and other air constituents and of a large scale free air carbon dioxide enrichment (FACE) experiment. The project is particularly designed to meet the data requirement of process and landscape models. The data will also c ontribute to the improvement and validation of models to predict the conseq uences of climate changes for agricultural ecosystems. The present contribu tion is a description of the structure of the experiments and the involveme nt of modelling approaches.