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Modelled effects of precipitation on ecosystem carbon and water dynamics in different climatic zones |
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| Authors: | DIETER GERTEN YIQI LUO GUERRIC Le MAIRE WILLIAM J. PARTON CINDY KEOUGH ENSHENG WENG CLAUS BEIER PHILIPPE CIAIS WOLFGANG CRAMER JEFFREY S. DUKES PAUL J. HANSON ALAN A. K. KNAPP SUNE LINDER DAN NEPSTAD LINDSEY RUSTAD ALWYN SOWERBY |
| Affiliation: | 1. Potsdam Institute for Climate Impact Research, Telegrafenberg A62, 14473 Potsdam, Germany,;2. Department of Botany and Microbiology, University of Oklahoma, Norman, OK 73019, USA,;3. Laboratoire des Sciences du Climat et de l'Environnement, UMR CEA-CNRS-UVSQ, L'Orme des Merisiers, Bat. 712, 91191 Gif-sur-Yvette, France,;4. Natural Resource Ecology Laboratory, University of Colorado, Campus Mail 1499, Fort Collins, CO 80523, USA,;5. Risø National Laboratory for Sustainable Energy, Biosystems Department, Building BIO-309, Frederiksborgvej 399, 4000 Roskilde, Denmark,;6. Potsdam Institute for Climate Impact Research, Telegrafenberg A62, 14473 Potsdam, Germany, 1Present address: Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement (CEREGE), BP 80, 13545 Aix-en-Provence Cedex 04, France.;7. Department of Biology, University of Massachusetts Boston, Boston, MA 02125, USA,;8. Oak Ridge National Laboratory, Environmental Sciences Division, Oak Ridge, TN 37831-6422, USA,;9. Department of Biology and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523, USA,;10. Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, PO Box 49, SE-23053 Alnarp, Sweden,;11. Woods Hole Research Center, PO Box 296, Woods Hole, MA 02543, USA,;12. USDA Forest Service, Northeastern Research Station, 35 Crystal Lane, Cumberland, ME 04021, USA,;13. Centre for Ecology and Hydrology, Orton Building, Deiniol Road, Bangor, Gwynedd LL57 2UP, UK |
| Abstract: | The ongoing changes in the global climate expose the world's ecosystems not only to increasing CO2 concentrations and temperatures but also to altered precipitation (P) regimes. Using four well-established process-based ecosystem models (LPJ, DayCent, ORCHIDEE, TECO), we explored effects of potential P changes on water limitation and net primary production (NPP) in seven terrestrial ecosystems with distinctive vegetation types in different hydroclimatic zones. We found that NPP responses to P changes differed not only among sites but also within a year at a given site. The magnitudes of NPP change were basically determined by the degree of ecosystem water limitation, which was quantified here using the ratio between atmospheric transpirational demand and soil water supply. Humid sites and/or periods were least responsive to any change in P as compared with moderately humid or dry sites/periods. We also found that NPP responded more strongly to doubling or halving of P amount and a seasonal shift in P occurrence than that to altered P frequency and intensity at constant annual amounts. The findings were highly robust across the four models especially in terms of the direction of changes and largely consistent with earlier P manipulation experiments and modelling results. Overall, this study underscores the widespread importance of P as a driver of change in ecosystems, although the ultimate response of a particular site will depend on the detailed nature and seasonal timing of P change. |
| Keywords: | climate change DGVM drought ecosystem modelling NPP precipitation soil respiration water limitation water stress |