藏北高寒草原土壤温度变化与冻融特征  

Soil Temperature Variation and Thaw-freezing Cycle in the Alpine Cold Steppe,Northern Tibetan Plateau

作　　者：李卫朋[1,2,3] 范继辉[1] 沙玉坤[1,3] 陈有超[1,3] 孙建[4] 程根伟[1] 

机构地区：[1]中国科学院水利部成都山地灾害与环境研究所,山地表生过程与生态调控重点实验室,四川成都610041 [2]西华师范大学国土资源学院,四川南充637002 [3]中国科学院大学,北京10049 [4]中国科学院地理科学与资源研究所,生态网络观测与模拟重点实验室,北京100101

出　　处：《山地学报》2014年第4期407-416,共10页Mountain Research

基　　金：国家自然科学基金项目(31070405);中国科学院西部行动计划项目(KZCX2-XB3-08);西华师范大学校基金项目(12A024)资助~~

摘　　要：冻融是藏北高寒区重要的自然环境特征和表生过程,冻融过程中土壤水分和热量迁移及其温湿度的时空分布特征对生态系统具有重要的意义。利用青藏高原申扎站高分辨土壤温度数据资料,对土壤温度不同时间尺度的变化特征,特别是冻融过程中土壤温度日和季节尺度变化特征进行分析。结果表明:观测期内,日尺度和月尺度上气温与土壤温度整体变化趋势具有一致性,但土壤温度变化相对缓和,且随着深度的增加,这种平缓趋势和时滞愈加明显;土壤温度冬春季变幅剧烈,反应了冻融过程对土壤温度的显著调节作用;小时尺度上,土壤温度昼夜变化过程大致呈现正弦波型,随深度增加,振幅减小,峰谷变化相位滞后延长。研究可为该区域生态、土壤、植被、微气候、微地貌等地表原位地理环境过程研究提供相关依据。Thaw-freezing cycle is the primary environment character and land surface processes in the alpine cold region, such as Northern Tibetan Plateau. The variation of soil temperature and soil moisture underground during the thaw-freezing processes are of great significance to ecosystems. The soil temperature, the basic effecting factor of the thaw-freezing cycle, was studied at Xainza at hourly to monthly scale, to offer references for the scientific re- search such as ecology, soil, land cover, microclimate, microtopography on the Northern Tibetan Plateau. The re- sults showed that the variation of soil temperature was similar to that of air temperature at daily to monthly scale for their robust correlation, while the soil temperature varied in a more slowly style with time-delays, which enhanced with the depth. Also, the soil temperature got strong coefficient of variation （CV） values during thaw phrase, indic- ting the effect of freezing-thawing processes on temperature. At hourly scale, the soil temperature varied in sine waves style, with the waves smoothed and delayed gradually for the increase of depth.

关 键 词：藏北高原 高寒草地 冻融循环 土壤水热过程 

分 类 号：Q948[生物学—植物学] S152[农业科学—土壤学]