摘要
大通河源区位于祁连山中东部,属高山多年冻土区,利用源区内冻土钻探及监测资料对源区冻土发育的基本特征及变化趋势进行了分析和探讨.冻土地温分析表明,源区冻土年平均地温随海拔的变化梯度约为3.82℃·km^-1,且冻土地温与表层覆被条件关系密切.盆地平原地带多年冻土厚度约为17～86 m,且以海拔每上升100 m冻土厚度增加约10 m的梯度增加.多年冻土活动层厚度受海拔地带性作用不显著,更多地受局地因素的控制,地表覆被条件成为其主要影响因素.在气温升高以及人类活动日益增多的影响下,源区冻土整体处于退化状态,多年冻土年平均地温以0.0075℃·a^-1的速率上升.
The source regions of the Datong River are located in the mid-east part of the Qilian Mountains with alpine permafrost. The characteristics and changing tendency of the permafrost were analyzed by using data from boreholes and surface observation. Regression analysis indicates that the mean annual ground temperature of permafrost in the source regions decreases with altitude with a gradient of about 3. 82 ℃ · km^-1. The mean annual ground temperature within the permafrost is affected by surface condition closely. The permafrost depth in the source regions is also significantly dependent on altitude. With the rising of elevation by 100 m,the thickness of permafrost increases about 10 m. In the plain areas,the depth of permafrost is ranging from 17 to 86 m.Active layer thickness is closely related to local factors,especially land cover condition. There is no clearly zonality relationship between active layer thickness and altitude. Under the impact of rising temperature and human activities,permafrost in the source regions is overall in the state of degradation,and the mean annual ground temperature is increasing at a rate of about 0. 0075 ℃ ·a^-1.
出处
《冰川冻土》
CSCD
北大核心
2015年第1期27-37,共11页
Journal of Glaciology and Geocryology
基金
国家自然科学基金项目(41271084)
国家自然科学基金创新研究群体项目(41121061)
国家重大基础研究发展计划(973计划)项目(2013CBA01803)资助
关键词
大通河源区
冻土分布
年平均地温
活动层
退化
source regions of the Datong River
permafrost distribution
mean annual ground temperature
active layer
degradation
作者简介
王生廷（1989-），男，甘肃武威人，2008年毕业于兰州理工大学，现为中国科学院寒区早区环境与工程研究所在读硕士研究生，主要从事冻土工程环境方面的研究．E-mail：wangshengting@lzb．ac．cn
通讯作者：盛煜，E-mail：sheng@lzb．ac．cn．
