title: Grazing exclusion reduced soil respiration but increased its temperature sensitivity in a Meadow Grassland on the Tibetan Plateau.
abstract: Understanding anthropogenic influences on soil respiration (R s) is critical for accurate predictions of soil carbon fluxes, but it is not known how R s responds to grazing exclusion (GE). Here, we conducted a manipulative experiment in a meadow grassland on the Tibetan Plateau to investigate the effects of GE on R s. The exclusion of livestock significantly increased soil moisture and above-ground biomass, but it decreased soil temperature, microbial biomass carbon (MBC), and R s. Regression analysis indicated that the effects of GE on R s were mainly due to changes in soil temperature, soil moisture, and MBC. Compared with the grazed blocks, GE significantly decreased soil carbon release by 23.6% over the growing season and 21.4% annually, but it increased the temperature sensitivity (Q10) of R s by 6.5% and 14.2% for the growing season and annually respectively. Therefore, GE may reduce the release of soil carbon from the Tibetan Plateau, but under future climate warming scenarios, the increases in Q10 induced by GE could lead to increased carbon emissions.
authors: State Key Laboratory of Loess and Quaternary Geology (SKLLQG), and Key Laboratory of Aerosol Chemistry and Physics Institute of Earth Environment Chinese Academy of Sciences Xi'an 710061 China; University of Chinese Academy of Sciences Beijing 100049 China.
authors: Ji
authors: J
authors: Chen
authors: Center for Global Change and Ecological Forecasting School of Ecological and Environmental Sciences East China Normal University Shanghai 200062 China.
authors: Xuhui
authors: X
authors: Zhou
authors: State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China.
authors: Junfeng
authors: J
authors: Wang
authors: Department of Environmental Science, Policy, and Management University of California at Berkeley Berkeley California 94720 USA.
authors: Tracy
authors: T
authors: Hruska
authors: State Key Laboratory of Loess and Quaternary Geology (SKLLQG), and Key Laboratory of Aerosol Chemistry and Physics Institute of Earth Environment Chinese Academy of Sciences Xi'an 710061 China.
authors: Weiyu
authors: W
authors: Shi
authors: State Key Laboratory of Loess and Quaternary Geology (SKLLQG), and Key Laboratory of Aerosol Chemistry and Physics Institute of Earth Environment Chinese Academy of Sciences Xi'an 710061 China; Institute of Global Environmental Change Xi'an Jiaotong University Xi'an 710049 China.
authors: Junji
authors: J
authors: Cao
authors: State Key Laboratory of Loess and Quaternary Geology (SKLLQG), and Key Laboratory of Aerosol Chemistry and Physics Institute of Earth Environment Chinese Academy of Sciences Xi'an 710061 China.
authors: Baocheng
authors: B
authors: Zhang
authors: Research Institute of Forest Ecology, Environment and Protection Chinese Academy of Forestry Beijing 100091 China.
authors: Gexi
authors: G
authors: Xu
authors: School of Life Science Nanjing University Nanjing 210093 China.
authors: Yizhao
authors: Y
authors: Chen
authors: Department of Microbiology and Plant Biology University of Oklahoma Norman Oklahoma 73019 USA; Center for Earth System Science Tsinghua University Beijing 100084 China.
authors: Yiqi
authors: Y
authors: Luo
keywords: Grazing exclusion; Tibetan Plateau; microbial biomass carbon; plant productivity; soil respiration; temperature sensitivity