气候变暖背景下沱沱河盆地多年冻土与融区地温过程研究  

Permafrost and taliks and their changes on the south and north banks of the Tuotuo River in the Qinghai-Tibet Plateau under the climate warming

作　　者：卫丁 赵廷虎 穆彦虎 刘富荣 丁泽琨 刘自成 WEI Ding;ZHAO Tinghu;MU Yanhu;LIU Furong;DING Zekun;LIU Zicheng(PLA Unit 32378,Beijing 100072,China;Sinohydro Bureau 6 Co.,Ltd.,Power China,Shenyang 110179,China;State Key Laboratory of Frozen Soil Engineering,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;University of Chinese Academy of Science,Beijing 100049,China;Guiyang Engineering Corporation Limited,Power China,Guiyang 550081,China)

机构地区：[1]中国人民解放军32378部队,北京100072 [2]中国水利水电第六工程局有限公司,辽宁沈阳110179 [3]中国科学院西北生态环境资源研究院,甘肃兰州730000 [4]中国科学院大学,北京100049 [5]中国电建集团贵阳勘测设计研究院有限公司,贵州贵阳550081

出　　处：《冰川冻土》2022年第2期427-436,共10页Journal of Glaciology and Geocryology

基　　金：国家自然科学基金项目(41772325);中国电建集团西南指挥部科技项目资助。

摘　　要：沱沱河盆地地处青藏高原腹地,区内多年冻土与融区分布复杂。多年冻土与融区的分布及其变化是冻土学研究的重要内容,同时对于居民生产、生活以及工程建设选址具有重要的意义。基于20世纪80年代已有研究中对沱沱河盆地多年冻土和融区的分区,利用北岸青藏铁路沿线5个钻孔(N1~N5)和南岸一级阶地5个钻孔(S1~S5)的地温观测数据,研究了沱沱河南北岸多年冻土与融区的地温及其变化过程。结果表明,在区域气候暖湿化背景下,北岸多年冻土、融区经历了显著的升温退化过程。自2005—2020年,N1孔位的多年冻土经历了显著的下引式退化过程,从极高温不稳定冻土已退化为融区。2005—2013年期间,融区内年平均地温升温速率为0.3~0.4℃·(10a)^(-1)。南岸自一级阶地至开心岭山前缓坡既有贯穿型也有非贯穿型融区的发育,融区的发育与河流与渗透-辐射机制以及冻结层上水发育有关。通过对盆地内10个钻孔的地温以及近20a的时间变化过程分析,加深了沱沱河盆地多年冻土与融区空间分布及其变化的认识。从盆地内多年冻土与融区的制图角度和工程建设需求出发,未来仍需要开展多手段现场勘察工作及对融区发育机制方面的深入研究。The distribution of permafrost and taliks is very complex in the Tuotuo River Basin(TRB),which is located in interior of the Qinghai-Tibet Plateau.Characterizing the spatial distribution and the thermal stability of permafrost and taliks is of great significance to community activities and engineering construction in TRB.Based on the zonation of permafrost and talik distribution around TRB conducted in the 1980s,the soil temperature and its variation process of permafrost and taliks in the south and north banks of the Tuotuo River were analyzed by using the observation data of five boreholes(N1~N5)along the Qinghai-Tibet Railway in the north bank and five boreholes(S1~S5)on the first terrace in the south bank.The results showed that,under the climate warming,permafrost and taliks in the north banks experienced significant degradation and warming process.From 2005 to 2020,the permafrost at the N1 borehole has undergone a significant down-draw degradation process,from extremely unstable and high-temperature permafrost to thawed zone.From 2005 to 2013,the annual average ground temperature of the talik at N2 increased at a rate of 0.3~0.4℃·(10a)^(-1).At Maqutang on the south bank,permafrost prevails from the first-class terrace to the gentle slope of the Kaixinling Mountain,with both through and non-through taliks on the first-class terrace.The spatial distribution and the thermal stability of permafrost and talik in the TRB are further promoted by analyzing the changes in temperatures at boreholes in the basin.However,to meet the requirements of mapping and engineering construction of permafrost and taliks in the TRB,it is still necessary to carry out geological investigation with multiple methods and in-depth research on development mechanism of taliks in the future.

关 键 词：青藏高原 沱沱河盆地 多年冻土 融区 地温 

分 类 号：P642.14[天文地球—工程地质学]