1. 主要研究内容

多年冻土变化及其碳反馈效应是气候变化研究的关键内容，也是当前全球变化研究中备受关注的重要科学问题。研究团队通过环北极和青藏高原的野外监测、实验分析和模型模拟，开展多年冻土碳库及其对气候变化的响应研究，在北半球多年冻土区活动层厚度分布、多年冻土区碳库储量与性质、多年冻土退化对碳分解与排放的影响方面取得了较为系统的创新成果。

2. 主要仪器设备

超低温冰箱、土壤前处理设备（离心机、抽提设备、水浴锅、振荡器）、马弗炉、烘干箱、便携式土壤碳通量仪、二氧化碳红外气体分析仪、气相色谱和精密土壤培养箱。

3. 团队成员：张廷军，牟翠翠，彭小清，鲁霞

4. 主要成果：

（1）揭示了不同气候条件下多年冻土碳的积累过程，给出了青藏高原多年冻土区深层碳库数据，厘清了土壤发生过程对碳含量和性质的影响。

（2）量化了多年冻土区惰性碳库的比例，给出了从负温到正温的升温过程中碳分解的变化规律，计算了不同深度碳分解的温度敏感性。

（3）发现多年冻土区的碳汇能力与活动层厚度有关，揭示了多年冻土退化会加速碳的原位分解和流失，为多年冻土区碳源汇效应、碳库平衡的计算及模拟提供了理论依据。

（4）定量化评估地表冻融、冻结深度、活动层厚度对气候变化的响应及其未来变化；探索冻土变化对于生态植被生长的影响以及土地覆盖类型变化对多年冻土的影响机制，为认识冻土生态调节功能以及预测未来变化提供科学依据。

代表性学术论文：

[1] Mu, C.C., Schuster, P.F., Abbott, B.W., Kang S.K., Guo, J.M., Sun, S.W., Wu, Q.B., Zhang, T.J. 2020. Permafrost degradation enhances the risk of mercury release on Qinghai-Tibetan Plateau. Science of the Total Environment, 708, 135127.

[2] Mu, C.C., Zhang, T.J., Zhang, X.K., Cao, B., Peng, X.Q., Cao, L., Su, H., 2016. Pedogenesis and physicochemical parameters influencing soil carbon and nitrogen of alpine meadows in permafrost regions in the northeastern Qinghai-Tibetan Plateau. Catena, 141, 85-91.

[3] Mu, C.C., Zhang, F., Mu, M., Chen, X., Li, Z.L., Zhang, T.J. 2020. Organic carbon stabilized by iron during slump deformation on the Qinghai-Tibetan Plateau. Catena, 187, 104282.

[4] Mu, C.C., Li, L.L., Wu, X.D., Zhang, F., Jia, L., Zhao, Q., Zhang, T.J., 2018. Greenhouse gas released from the deep permafrost in the northern Qinghai-Tibetan Plateau. Scientific Reports, 8: 4205.

[5] Mu, C.C., Zhang, T.J., Zhang, X.Y., Cao, B., Peng, X.Q., 2016. Sensitivity of soil organic matter decomposition to temperature at different depths in permafrost regions on the northern Qinghai‐Tibet Plateau. European Journal of Soil Science, 67, 773-781.

[6] Mu, C.C., Zhang, T.J., Zhao, Q., Guo, H., Zhong, W., Su, H., Wu, Q.B., 2016. Soil organic carbon stabilization by iron in permafrost regions of the Qinghai‐Tibet Plateau. Geophysical Research Letters, 43, 10286-10294.

[7] Mu, C.C., Shang, J.G., Zhang, T.J., Fan, C.Y., Wang, S.F., Peng, X.Q., Zhong, W., Zhang, F., Mu, M., Jia, L. 2020. Acceleration of thaw slump during 1997–2017 in the Qilian Mountains of the northern Qinghai-Tibetan plateau. Landslides, DOI 10.1007/s10346-020-01344-3.

[8] Mu, C.C., Zhang, F., Chen, X., Ge, SM., Mu, M., Jia, L., Wu, QB., Zhang, T.J. 2019. Carbon and mercury export from the Arctic rivers and response to permafrost degradation. Water Research, 161, 54-60.

[9] Mu, C.C., Abbott, B.W., Wu, X.D., Zhao, Q., Wang, H.J., Su, H., Wang, S.F., Gao, T.G., Peng, X.Q., Zhang, T.J., 2017. Thaw depth determines dissolved organic carbon concentration and biodegradability on the northern Qinghai-Tibetan Plateau. Geophysical Research Letters, 44, 9389-9399.

[10] Mu, C.C., Abbott, B.W., Zhao, Q., Su, H., Wang, S.F., Wu, Q.B., Zhang, T.J., Wu, X.D., 2017. Permafrost collapse shifts alpine tundra to a carbon source but reduces N2O and CH4 release on the northern Qinghai-Tibetan Plateau. Geophysical Research Letters, 44, 8945-8952.

[11] Mu, C.C., Wu, X.D., Zhao, Q., Smoak, J.M., Yang, Y.L., Hu, L.A., Zhong, W., Liu, G.M., Xu, H.Y., Zhang, T.J., 2017. Relict mountain permafrost area (Loess Plateau, China) exhibits high ecosystem respiration rates and accelerating rates in response to warming. Journal of Geophysical Research: Biogeosciences, 122, 2580-2592.

[12] Mu, C.C., Zhang, T.J., Wu, Q.B., Peng, X.Q., Zhang, P., Yang, Y.Z., Hou, Y.H., Zhang, X.K., Cheng, G.D., 2016. Dissolved organic carbon, CO2, and CH4 concentrations and their stable isotope ratios in thermokarst lakes on the Qinghai-Tibetan Plateau. Journal of Limnology, 75, 313-319.

[13] Mu, C.C., Zhang, T.J., Zhang, X.K., Li, L.L., Guo, H., Zhao, Q., Cao, L., Wu, Q.B., Cheng, G.D., 2016. Carbon loss and chemical changes from permafrost collapse in the northern Tibetan Plateau. Journal of Geophysical Research: Biogeosciences, 121, 1781-1791.

[14] Mu, C.C., Li, L.L., Zhang, F., Li, Y.X., Xiao, X.X., Zhao, Q., Zhang, T.J., 2018. Impacts of permafrost on above- and belowground biomass on the northern Qinghai-Tibetan Plateau. Arctic, Antarctic, and Alpine Research, 50: 1, e1447192.

[15] Peng, X.Q., Zhang, T.J., Frauenfeld, O.W., Wang, S.J.*, Qiao, L.N., Du R., Mu C.C.*, Northern Hemisphere Greening in Association With Warming Permafrost Journal of Geophysical Research: Biogeosciences, 2019, 1251-20.

[16] Peng, X.Q., Zhang, T.J., Frauenfeld, O.W., Du R., Permafrost Response to Land Use and Land Cover Change in the Last Millennium across the Northern Hemisphere, Land Degradation & Development, 2020, 31, 1823-1836.

[17] Peng, X.Q., Zhang, T.J., Frauenfeld, O.W., Du R., Wei Q, Liang B.B, Soil Freeze Depth Variability Across Eurasia During 1850–2100, Climatic Change, 2019, 158, 531–549.

[18] Peng, X.Q., Zhang, T.J., Frauenfeld, O.W., Wang K, Sun W, Luo J, Evaluation and quantification of surface air temperature over Eurasia based on CMIP5 models, Climate Research, 2019, 77, 167-180.

[19] Peng, X.Q., Zhang, T.J., Frauenfeld, O.W., Liu Y.J, Luo J, Past and Projected Freezing/Thawing Indices in the Northern Hemisphere, Journal of Applied Meteorology and Climatology, 2019, 58, 495-510.

[20] Peng, X.Q., Zhang, T.J., Frauenfeld, O.W., Wang K, Luo D.L, Cao B, Su H, Jin H.J, Wu Q.B, Spatiotemporal changes in active layer thickness under contemporary and projected climate in the Northern Hemisphere, Journal of Climate, 2018, 31: 251-266.

[21] Peng X.Q, Mu C.C, Changes of soil thermal and hydraulic regimes in the HeiheRiver Basin, Environmental Monitoring and Assessment, 2017, 189 (10):483.

[22] Peng, X.Q., Zhang, T.J., Frauenfeld, O.W., Wang K, Cao B, Zhong X.Y, Su H, Mu C.C, Response of seasonal soil freeze depth to climate change across China, The Cryosphere, 2017, 11:1059-1073.

[23] Peng, X.Q., Frauenfeld, O.W., Cao B, Wang K, Wang H.J, Su H, Huang Z, Yue D.X, Zhang, T.J., Response of Changes in Seasonal Soil Freeze/Thaw State to Climate Change from 1950 to 2010 across China, Journal of Geophysical Research: Earth Surface, 2016, 121:1984-2000.

[24] Peng, X.Q., Zhang, T.J., Cao B, Wang Q.F, Wang K, Shao W.W, Guo H, Changes in freezing-thawing index and soil freeze depth over the Heihe River Basin, western China, Arctic, Antarctic, and Alpine Research, 2016, 48: 161-176.

[25]马素辉, 牟翠翠, 郭红, 张现凯, 栗泽苑, 张廷军. 2018. 祁连山区黑河上游多年冻土区不同植被类型土壤有机碳密度分布特征. 冰川冻土, 40 (3), 429-433.

[26] 张凤, 母梅, 范成彦, 贾麟, 牟翠翠*, 赵倩, 李丽丽, 彭小清, 张廷军. 2020. 从第三极到北极：多年冻土碳循环研究进展.冰川冻土, 42 (1), 1-12.

[27] 贾麟, 范成彦, 母梅, 陈旭, 仲文, 尚建国, 张凤, 李丽丽, 彭小清, 牟翠翠*, 张廷军. 2020. 从第三极到北极：热喀斯特及其对碳循环影响研究进展.冰川冻土, 42 (1), 157-169.