影响多年冻土上限变化的因素探讨  

A Study of Factors Which Control Variation of Permafrost Table

作　　者：王银学[1] 赵林[1] 李韧[1] 吴通华[1] 乔永平[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所青藏高原冰冻圈观测研究站,甘肃兰州730000

出　　处：《冰川冻土》2011年第5期1064-1067,共4页Journal of Glaciology and Geocryology

基　　金：国家自然科学基金项目(40835033;40871037;40901042);国家重点基础研究发展计划(973计划)项目(2007CB411504);冰冻圈科学国家重点实验室自主课题(SKLCS-ZZ-2010-03)资助

摘　　要：利用地温及活动层水热观测资料,分析青藏公路沿线近年来影响多年冻土上限的变化因素.研究结果显示,青藏公路沿线冻土上限总体呈现下降趋势,冻土上限的变化与近年来区域气候变化的趋势一致;近年来多年冻土上限下降0.1～0.5 m,所处的地理位置不同,冻土上限下降的幅度也不同.气温变化是影响冻土上限的一个重要的外部因素,上限变化的幅度也还受地理环境及植被覆盖度和岩性所制约.研究多年冻土上限是将自然变化的控制条件转为人为控制因素,更好地为工程施工和建设服务.In this paper,factors which control the variation of permafrost table along the Qinghai-Tibet Highway were analyzed based on date of the active layers,borehole＇s ground temperatures and hydrothermal observation.It is found that the permafrost table along the Qinghai-Tibet Highway has a decreasing tendency overall,consistent with the regional tendency climate change of recent years.Permafrost table has declined by 0.1～0.5 m dependent on geographical position.Air temperature change is one of the significant external factors which control the permafrost table.The extent of change of permafrost table is also limited by geographical environment and soil internal structures.The study of permafrost table changes aims to turning its control condition from natural to artificial,which is very important for engineering constructions.

关 键 词：冻土上限 冻土环境 覆盖度 岩性 

分 类 号：P642.14[天文地球—工程地质学]