BG Biogeosciences BG Biogeosciences 1726-4189 Copernicus Publications Göttingen, Germany 10.5194/bg-8-1453-2011 Thermal adaptation of net ecosystem exchange Yuan W. 1 2 Luo Y. 2 Liang S. 1 3 Yu G. 4 Niu S. 2 5 Stoy P. 6 Chen J. 7 Desai A. R. 8 Lindroth A. 9 Gough C. M. 10 Ceulemans R. 11 Arain A. 12 Bernhofer C. 13 Cook B. 14 Cook D. R. 15 Dragoni D. 16 Gielen B. 11 Janssens I. A. 11 Longdoz B. 17 Liu H. 18 Lund M. 19 Matteucci G. 20 Moors E. 21 Scott R. L. 22 Seufert G. 23 Varner R. 24 College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China Department of Botany and Microbiology, University of Oklahoma, Norman, OK 73019, USA Department of Geography, University of Maryland, College Park, MD 20742, USA Key Laboratory of Ecosystem Network Observation and Modeling, Synthesis Research Center of Chinese Ecosystem Research Network, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing 100093, China Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT 59717-3120, USA Department of Environmental Sciences, University of Toledo, Toledo, OH 43606-3390, USA Atmospheric and Oceanic Sciences Department, University of Wisconsin – Madison, Madison, WI 53706, USA Department of Physical Geography and Ecosystem Analysis, Lund University, Sölvegatan 12, 223 62, Sweden Department of Biology, Virginia Commonwealth University, Richmond, VA 23284-2012, USA Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium School of Geography and Earth Sciences, and McMaster Centre for Climate Change, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4K1, Canada Institute of Hydrology and Meteorology, Technische Universität Dresden, 01737 Tharandt, Germany Biospheric Science, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA Climate Research Section, Environmental Science Division, Argonne Nat. Lab., Lemont, IL 60439, USA Atmospheric Science Program, Geography Department, Indiana University, Bloomington, IN 47405-7100, USA INRA, UMR1137 Ecologie et Ecophysiologie Forestière, Centre de Nancy, 54280 Champenoux, France Laboratory for Atmospheric Research, Department of Civil and Environmental Engineering, Washington State University, Pullman, WA 99164-2910, USA Department of Arctic Environment, National Environmental Research Institute, Aarhus University, Frederiksborgvej, 4000 Roskilde, Denmark Institute for Agricultural and Forestry Systems in the Mediterranean, Via Cavour, Rende 4-6, 87036, Italy ESS-CC, Alterra Wageningen UR, 6700 AA Wageningen, The Netherlands Southwest Watershed Research Center, USDA-ARS, Tucson, AZ 85719, USA Institute for Environment and Sustainability, Joint Research Centre – European Commission, 21027 Ispra, Italy Institute for the Study of Earth, Oceans and Space and Earth Sciences, University of New Hampshire, Durham, NH 03824, USA 06 06 2011 8 6 1453 1463 Copyright: © 2011 W. Yuan et al. 2011 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://bg.copernicus.org/articles/8/1453/2011/bg-8-1453-2011.html The full text article is available as a PDF file from https://bg.copernicus.org/articles/8/1453/2011/bg-8-1453-2011.pdf

Thermal adaptation of gross primary production and ecosystem respiration has been well documented over broad thermal gradients. However, no study has examined their interaction as a function of temperature, i.e. the thermal responses of net ecosystem exchange of carbon (NEE). In this study, we constructed temperature response curves of NEE against temperature using 380 site-years of eddy covariance data at 72 forest, grassland and shrubland ecosystems located at latitudes ranging from ~29° N to 64° N. The response curves were used to define two critical temperatures: transition temperature (<i>T</i><sub>b</sub>) at which ecosystem transfer from carbon source to sink and optimal temperature (<i>T</i><sub>o</sub>) at which carbon uptake is maximized. <i>T</i><sub>b</sub> was strongly correlated with annual mean air temperature. <i>T</i><sub>o</sub> was strongly correlated with mean temperature during the net carbon uptake period across the study ecosystems. Our results imply that the net ecosystem exchange of carbon adapts to the temperature across the geographical range due to intrinsic connections between vegetation primary production and ecosystem respiration.

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