Effects of Elevated Air Temperatures on Soil Thermal and Hydrologic Processes in the Active Layer in an Alpine Meadow Ecosystem of the Qinghai-Tibet Plateau

作     者：BAI Wei WANG Genxu LIU Guangsheng 

作者机构：School of Environmental and Municipal EngineeringLanzhou Jiaotong UniversityLanzhou 730070China College of Resource and Environmental ScienceLanzhou UniversityLanzhou 730000China Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China 

出 版 物：《Journal of Mountain Science》 (山地科学学报（英文）)

年 卷 期：2012年第9卷第2期

页      面：243-255页

核心收录：

学科分类：0709[理学-地质学] 0819[工学-矿业工程] 07[理学] 070601[理学-气象学] 09[农学] 0303[法学-社会学] 0708[理学-地球物理学] 0818[工学-地质资源与地质工程] 0705[理学-地理学] 0815[工学-水利工程] 0903[农学-农业资源与环境] 0706[理学-大气科学] 0816[工学-测绘科学与技术] 0813[工学-建筑学] 0704[理学-天文学] 0833[工学-城乡规划学] 0713[理学-生态学] 0834[工学-风景园林学（可授工学、农学学位）] 

基　　金：founded by The National Science Foundation of China(No.40730634 andNo.40925002) 

主　　题：高寒草甸生态系统 温度升高 水文过程 青藏高原 空气温度 土壤热 有源层 土壤水分 

摘      要：In this study,effects of elevated air temperatures on thermal and hydrologic process of the shallow soil in the active layer were investigated. Open-top chambers(OTCs)were utilized to increase air temperatures 1-2℃ in OTC-1 and 3-5℃ in OTC-2 in the alpine meadow ecosystem on the Qinghai- Tibetan *** show that the annual air temperatures under OTC-1 and OTC-2 were 1.21℃ and 3.62℃ higher than the Control,*** entirely-frozen period of shallow soil in the active layer was shortened and the fully thawed period was prolonged with temperature *** maximum penetration depth and duration of the negative isotherm during the entirely-frozen period decreased, and soil freezing was retarded in the local scope of the soil profile when temperature ***, the positive isotherm during the fully-thawed period increased,and the soil thawing was *** moisture under different manipulations decreased with the temperature increase at the same depth. During the early freezing period and the early fully- thawed period,the maximum soil moisture under the Control manipulation was at 0.2 m deep,whereas under OTC-1 and OTC-2 manipulations,the maximum soil moisture were at 0.4-0.5 m deep. These results indicate that elevated temperatures led to a decrease of the moisture in the surface *** coupled relationship between soil temperature and moisture was significantly affected by the temperature *** the freezing and thawing processes, the soil temperature and moisture under different manipulations fit the regression model given by the equationθV=a/{1+exp[b(TS+c)]}+d.