巴颜喀拉山青康公路沿线多年冻土和活动层分布特征及影响因素  

Distributive Features and Controlling Factors of Permafrost and the Active Layer Thickness in the Bayan Har Mountains along the Qinghai-Kangding Highway on Northeastern Qinghai-Tibet Plateau

作　　者：罗栋梁[1] 金会军[1] 林琳[1] 游艳辉[1] 杨思忠[1] 王永平[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,甘肃兰州730000

出　　处：《地理科学》2013年第5期635-640,共6页Scientia Geographica Sinica

基　　金：国家自然科学基金委创新群体项目(41121061);全球变化研究国家重大科学研究计划项目(2010CB951402)资助

摘　　要：巴颜喀拉山是较典型的高海拔多年冻土区。南、北坡迥异的气候、土壤及地表景观控制和影响其多年冻土空间分布。2008~2012年冻土调查及测温资料表明，该山以高温冻土（〉-1℃）为主。海拔是冻土主要影响因素。年均地温随海拔升高而降低的高程递减率在北坡6℃／km，南坡4℃／km。北坡查拉坪及巴颜喀拉山口一带，活动层厚度约1m，活动层随海拔降低而增厚；南坡活动层厚度受局地因素影响较大，与海拔无明显相关。Permafrost on the Qinghai-Tibet Plateau （QTP） is elevational, where the permafrost accounts for approximately 75% of the elevational permafrost in the Northrn hemisphere. Located in the transition zone from the Qinghai-Tibet Plateau higher than 4 500 m a. s. 1. to the Loess Plateau at less than 2 000 m a. s. 1., the Bay- an Har Mountains （BHM） have typical alpine permafrost. The intensive uplifts of the BHM have resulted in a great variety in climate, permafrost and landscapes on the north and south slopes. Based on field investigations and ground temperature measurements between 2008-2012, the distributive features and controlling/influenc- ing factors of permafrost in the BHM are revealed in detail in this paper. Most permafrost in the BHM is warm （〉-1 ~C）, except that at some mountain tops such as Chalaping and the Bayan Har Mountain Pass. The ground temperature in the BHM is principally controlled by elevations. The lowest MAGT of-l.8℃ and the thickest permafrost of 74 m are found at Chalaping higher than 4 700 m a. s. 1. The lapse rate of MAGT with rising elevation is 6℃/kin on the north slopes and 4℃/kin on the south slopes, respectively. The MAGTs are -0.2℃ in Borehole YNG-1 at the north-slope toes, and ＋0.3℃ in Borehole QSH-1 at the south-slope toes. Permafrost thins rapidly downwards at both slope toes. The MAGTs are lower than -0.5 ℃ at elevations above 4 570 m a. s. 1. on the south slopes and above 4 527 m a. s. 1. on the north slopes. The MAGTs are lower.than -1 ℃ at eleva- tions above 4 670 m a. s. 1. on the south slopes and above 4 615 m a. s. 1. on the north slopes. The zone boundaries of-0.5℃ in mean annual ground temperatures largely coincide with the lower limits of sporadic （discontinuous） permafrost, and zone boundaries of-1 ℃ correspond to the lower limits of continuous permafrost. The active layer thickness, which usually affected by the lithology （soil types） and moisture conditions, is about 1 m at the Bayan Har Mountain Pass and Chalaping on the n

关 键 词：巴颜喀拉山 高海拔多年冻土 年平均地温 高程递减率 活动层 

分 类 号：P642.14[天文地球—工程地质学]