黑河流域中游灌区含水层系统异质性对地表热通量和温度的影响模拟  

Impacts of Subsurface Aquifer Heterogeneity on Surface Heat Fluxes and Temperature:A Case Study in the Irrigation Area in the Middle Reaches of the Heihe River Basin

作　　者：陆峥 孙景博 何源 李宗超 彭书艳 杨晓帆 LU Zheng;SUN Jing-bo;HE Yuan;LI Zong-chao;PENG Shu-yan;YANG Xiao-fan(State Key Laboratory of Earth Surface Processes and Resource Ecology,Faculty of Geographical Science,Beijing Normal University,Beijing 100875;Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou),Guangzhou 511458;China National Environmental Monitoring Centre,Beijing 100012,China)

机构地区：[1]北京师范大学地理科学学部,地表过程与资源生态国家重点实验室,北京100875 [2]南方海洋科学与工程广东省实验室(广州),广州广东511458 [3]中国环境监测总站,北京100012

出　　处：《地理与地理信息科学》2021年第6期7-15,共9页Geography and Geo-Information Science

基　　金：中国科学院A类战略性先导科技专项项目(XDA20100104)。

摘　　要：渗透系数是描述地下含水层系统空间异质性的重要参数,直接影响地下水位和浅层土壤水分分布,并最终间接影响地表辐射收支及地气间能量转换。基于三维物理过程的地下水—陆面过程耦合模型ParFlow-CLM,在黑河流域中游灌区开展数值模拟实验,分析4种渗透系数情景下地下水位埋深、地表热通量和温度的差异。结果表明,忽略水平方向异质性会降低地表热通量的模拟精度,同时设置水平和垂直方向异质性并考虑包气带—饱水带三维水力特征可提高地表温度的模拟精度;充分考虑土壤和含水层系统异质性能提高分层(尤其是0.2~0.5 m深度土层)土壤温度的模拟精度;土壤和含水层系统异质性对地表热通量和温度的控制作用受到下垫面、地形等环境因素的显著影响,尤其在裸地区域,地表感热通量和温度的模拟结果差异较大。研究结果可为干旱—半干旱地区高时空分辨率水文集成模型的构建提供科学依据。Hydraulic conductivity is a most important parameter to describe the physical property and heterogeneity of subsurface aquifer,which drives the groundwater flow and solute transport processes.It directly alters the groundwater level and shallow soil water distribution,and thus indirectly influences the radiation balance and energy flux between land surface and atmosphere.A three-dimensional process-based integrated hydrologic model ParFlow-CLM is used to simulate and inter-compare the differences of water table depth,surface heat flux and temperature under four subsurface hydraulic conductivity scenarios in the middle reaches of the Heihe River Basin.Results show that the simulation accuracy of sensible heat flux and latent heat flux will be reduced when the horizontal heterogeneity is ignored,and the simulation accuracy of land surface temperature can be improved by setting horizontal and vertical heterogeneity and considering the three-dimensional subsurface hydraulic characteristics of aeration zone and saturated zone.Meanwhile considering the heterogeneity of soil and aquifer system can improve the accuracy of soil temperature estimations,especially at the depth from 0.2 m to 0.5 m.The effect of subsurface aquifer heterogeneity on surface heat flux and temperature is also controlled by environmental factors,such as land cover and topography.Especially in the bare land area,the simulation results of surface sensible heat flux and temperature are of great difference.The study is expected to provide scientific guidance on integrated hydrologic modeling with high spatial-temporal resolution in arid and semi-arid regions.

关 键 词：土壤和含水层系统异质性 渗透系数 水文集成模型 地表热通量 黑河流域中游 农业灌溉 

分 类 号：P339[天文地球—水文科学]