黄河源区多年冻土温度及厚度研究新进展

利用新布设的冻土孔及原有冻土资料,分析黄河源区冻土温度和厚度的空间分布。源区实测多年冻土年均地温最低为-1.81℃,冻土最厚74 m,均位于巴颜喀拉山北坡的查拉坪。214国道(K445-K604段)沿线多为高温多年冻土(年均地温>-1℃),但巴山北坡海拔4 520 m、布青山海拔4 300 m以上,年均地温低于-0.5℃。巴山北坡海拔4 610 m、布青山海拔4 420 m以上,年均地温低于-1℃。巴山北坡海拔每升高100 m,年均地温减少0.47~0.75℃,冻土厚度增加16~25 m;纬度向北增加1°,年均地温减少0.85℃,冻土厚度增加20~30 m。

New Progress on Permafrost Temperature and Thickness in the Source Area of the Huanghe River

Based on data and information from newly set-up and original permafrost boreholes,the permafrost temperature and thickness in the Source Area of the Huanghe River were analyzed.The lowest permafrost temperature at depth of zero annual amplitude(DZZA)(so-called the MAGT) in-situ is-1.81℃,and deepest permafrost is 74 m,both are located on the north slope of the Bayan Har Mountains.Most permafrost along the National Highway No.214(K445-K604) is warm permafrost(with the MAGT>-1℃).However,with altitude higher than 4 520 m in the north slope of the Bayan Har Mountains,and higher than 4 300 m in the Buqing Mountains,the MAGT is lower than-0.5℃.With altitude higher than 4 610 m in the north slope of the Bayan Har Mountains,and higher than 4 420 m in the Buqing Mountains,the MAGT is lower than-1℃.In the Bayan Har Mountains,the MAGT decreases with altitude at rates of 0.47-0.75℃/100 m,and permafrost thickness increase 16-25 m/100 m.Besides,the MAGT decreases with latitude at rates of 0.85℃ and permafrost thickness increase about 20-30 m per degree.