caa a22 4500 445383658 CHVBK 20180317143025.0 cr unu---uuuuu 170323e20111101xx s 000 0 eng 10.1007/s10021-011-9464-4 doi (NATIONALLICENCE)springer-10.1007/s10021-011-9464-4 Responses of Ecosystem Carbon Cycling to Climate Change Treatments Along an Elevation Gradient [Elektronische Daten] [Zhuoting Wu, George Koch, Paul Dijkstra, Matthew Bowker, Bruce Hungate] Global temperature increases and precipitation changes are both expected to alter ecosystem carbon (C) cycling. We tested responses of ecosystem C cycling to simulated climate change using field manipulations of temperature and precipitation across a range of grass-dominated ecosystems along an elevation gradient in northern Arizona. In 2002, we transplanted intact plant-soil mesocosms to simulate warming and used passive interceptors and collectors to manipulate precipitation. We measured daytime ecosystem respiration (ER) and net ecosystem C exchange throughout the growing season in 2008 and 2009. Warming generally stimulated ER and photosynthesis, but had variable effects on daytime net C exchange. Increased precipitation stimulated ecosystem C cycling only in the driest ecosystem at the lowest elevation, whereas decreased precipitation showed no effects on ecosystem C cycling across all ecosystems. No significant interaction between temperature and precipitation treatments was observed. Structural equation modeling revealed that in the wetter-than-average year of 2008, changes in ecosystem C cycling were more strongly affected by warming-induced reduction in soil moisture than by altered precipitation. In contrast, during the drier year of 2009, warming induced increase in soil temperature rather than changes in soil moisture determined ecosystem C cycling. Our findings suggest that warming exerted the strongest influence on ecosystem C cycling in both years, by modulating soil moisture in the wet year and soil temperature in the dry year. Springer Science+Business Media, LLC, 2011 warming nationallicence precipitation nationallicence gross ecosystem photosynthesis nationallicence ecosystem respiration nationallicence net ecosystem exchange nationallicence structural equation model nationallicence Wu Zhuoting Department of Biological Sciences and Merriam-Powell Center for Environmental Research, Northern Arizona University, 86011, Flagstaff, Arizona, USA aut Koch George Department of Biological Sciences and Merriam-Powell Center for Environmental Research, Northern Arizona University, 86011, Flagstaff, Arizona, USA aut Dijkstra Paul Department of Biological Sciences and Merriam-Powell Center for Environmental Research, Northern Arizona University, 86011, Flagstaff, Arizona, USA aut Bowker Matthew US Geological Survey, Southwest Biological Science Center, Northern Arizona University, P.O. Box 5614, 86011, Flagstaff, Arizona, USA aut Hungate Bruce Department of Biological Sciences and Merriam-Powell Center for Environmental Research, Northern Arizona University, 86011, Flagstaff, Arizona, USA aut Ecosystems Springer-Verlag 14/7(2011-11-01), 1066-1080 1432-9840 14:7<1066 2011 14 10021 https://doi.org/10.1007/s10021-011-9464-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10021-011-9464-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wu Zhuoting Department of Biological Sciences and Merriam-Powell Center for Environmental Research, Northern Arizona University, 86011, Flagstaff, Arizona, USA aut NATIONALLICENCE 700 1- Koch George Department of Biological Sciences and Merriam-Powell Center for Environmental Research, Northern Arizona University, 86011, Flagstaff, Arizona, USA aut NATIONALLICENCE 700 1- Dijkstra Paul Department of Biological Sciences and Merriam-Powell Center for Environmental Research, Northern Arizona University, 86011, Flagstaff, Arizona, USA aut NATIONALLICENCE 700 1- Bowker Matthew US Geological Survey, Southwest Biological Science Center, Northern Arizona University, P.O. Box 5614, 86011, Flagstaff, Arizona, USA aut NATIONALLICENCE 700 1- Hungate Bruce Department of Biological Sciences and Merriam-Powell Center for Environmental Research, Northern Arizona University, 86011, Flagstaff, Arizona, USA aut NATIONALLICENCE 773 0- Ecosystems Springer-Verlag 14/7(2011-11-01), 1066-1080 1432-9840 14:7<1066 2011 14 10021 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer