Water regime of model forest ecosystems under elevated CO2 and nitrogen deposition

In this project we assessed the influence of elevated atmospheric CO2 concentration and nitrogen deposition on the water regime of a model forest ecosystem on two different soils. Four replicate lysimeters were installed for each combination of soil and treatment. The water balances of the 32 lysimeters were determined once a week since May 1995. In accordance with our hypothesis, elevated CO2 reduced evapotranspiration on the acidic soil in summer. On the calcareous soil such an effect was only seen in June. Elevated nitrogen deposition tended to increase evapotranspiration on both soils in summer.