Journal Article Tibetan Plateau 7440-44-0 Carbon Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Soil soil heterotrophic respiration 142M471B3J Carbon Dioxide alpine meadow asymmetric warming carbon cycling carbon turnover time climate change community composition community stability context dependency degradation ecosystem CO2 flux ecosystem respiration freeze-thaw events grazing labile carbon limitation microbial community response moderate grazing number and frequency of freeze-thaw cycles plant functional group precipitation addition random forest