www.biogeosciences-discuss.net/3/1473/2006/ © Author(s) 2006. This work is licensed under a Creative Commons License. Effects of climate warming and declining species richness in grassland model ecosystems: acclimation of CO2 fluxes 1Research Group of Plant and Vegetation Ecology, Department of Biology, University of Antwerp (Campus Drie Eiken), Universiteitsplein 1, 2610 Wilrijk, Belgium 2Department of Applied Physics, University of Granada, C/ Fuentenueva S/N, 18071 Granada, Spain Abstract. To study the effects of warming and declining species richness on the carbon balance of grassland communities, model ecosystems containing one, three or nine species were exposed to ambient and elevated (ambient +3°C) air temperature. In this paper, we analyze measured ecosystem CO2 fluxes to test whether ecosystem photosynthesis and respiration had acclimated to warming after 28 months of continuous heating, and whether the degree of acclimation depended on species richness. At first sight, we found no signs of acclimation in photosynthesis or respiration. However, because plant cover was significantly higher in the heated treatment, normalization for plant cover revealed down-regulation of both photosynthesis and respiration. Although CO2 fluxes were larger in communities with higher species richness, species richness did not affect the degree of acclimation to warming. These results imply that models need to take into account thermal acclimation to simulate photosynthesis and respiration in a warmer world. Discussion Paper (PDF, 436 KB) Interactive Discussion (Closed, 4 Comments) Final Revised Paper (BG) Citation: Vicca, S., Serrano-Ortiz, P., De Boeck, H. J., Lemmens, C. M. H. M., Nijs, I., Ceulemans, R., Kowalski, A. S., and Janssens, I. A.: Effects of climate warming and declining species richness in grassland model ecosystems: acclimation of CO2 fluxes, Biogeosciences Discuss., 3, 1473-1498, 2006. Bibtex EndNote Reference Manager |
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