FACE-Based Crop Responses to Projected CO2 and Climate Changes in Germany
Kersebaum, K.C., Nendel, C., Mirschel, W., Manderscheid, R., Weigel, H.-J. and Wenkel, K.-O. 2009. Testing different CO2 response algorithms against a face crop rotation experiment and application for climate change impact assessment at different sites in Germany. Quarterly Journal of the Hungarian Meteorological Service 113: 79-88.
Kersebaum et al. report that the FACE experiment "showed two important results: increased CO2 (i) enhanced crop growth for all investigated species and (ii) decreased evapotranspiration rate of the canopies resulting in higher soil moisture content (Weigel et al., 2006)." As a result, they found that "without consideration of the CO2 effect, mostly negative impacts on crop yields were simulated," but that "considering the CO2 effect compensated the negative trend in most cases and turned yield effects to a positive impact."
Given such findings, if the temperature increases and precipitation decreases predicted for Germany in the 2031-2050 time period ever occur, the increase in the atmosphere's CO2 concentration that is predicted to accompany them appears capable of leading to a concurrent increase in the productivity of "a typical agricultural crop rotation in Germany."
Weigel, H.J. and Dammgen, U. 2000. The Braunschweig Carbon Project: atmospheric flux monitoring and free air carbon dioxide enrichment (FACE). Journal of Applied Botany 74: 55-60.
Weigel, H.J., Manderscheid, R., Burkart, S., Pacholski, A., Waloszczyk, C.K., Fruhauf, O. and Heinemeyer, O. 2006. Responses of an arable crop rotation system to elevated CO2. In Nosberger et al. (Eds.), Managed Ecosystems and CO2 Case Studies, Processes and Perspectives. Ecological Studies 187: 121-137.