In order to reveal the effect of vegetation degradation on soil carbon(SOC)mineralization in wetland

four intensities of vegetation degradation of Gahai wetland (non-degraded (UD)

slightly degraded (LD)

moderately degraded (MD)

and heavily degraded (HD)) were selected for the research objects on the eastern Qinghai-Tibet Plateau.Soil samples (0-40 cm) were collected from three depths (0-10

10-20 and 20-40 cm). SOC mineralization was determined by the laboratory incubation method.The first-order kinetic equation were applied to analyze the response of soil semi-mineralization decomposition time (T1/2) and organic carbon mineralization potential (C0) to vegetation degradation.The result showed that: (1) SOC mineralization rate displayed similar trends during the four vegetation degradation stages: during the early incubation period(0~4 day)

SOC mineralization rate was high and decreased fast

and then the rate decreased slowly and tend to stabilize during the middle and late periods(4~41 day).The order of SOC mineralization rate in different vegetation degradation stages was UD > LD > MD > HD at all temperatures. (2) During the whole incubation period

the SOC mineralization rate in different vegetation degradation stages decreased with increasing soil depth. The SOC mineralization rate in different vegetation degradation stages were 1.14~16.23 mg/ (g·d)

significantly higher than those in 10-20 cm layer (1.05~2.85 mg/(g·d)) and 20-40 cm layer (0.94~1.26 mg/(g·d)). (3) The order of average cumulative amount of SOC mineralization with four vegetation stages at different temperatures was 5 ℃ (34.54 mg/g) > 15 ℃ (46.67 mg/g) > 25 ℃ (58.28 mg/g) > 35 ℃ (86.46 mg/g).(4) The C0 value of first-order kinetic equation decreased with increasing degradation degree

while the C0/SOC decreased with increasing temperature. Therefore

vegetation degradation in the alpine wetland significantly decreased the SOC mineralization rate and climate warming significantly increased the cumulative amount of SOC mineralization.