稳定蒸发条件下的深厚包气带土壤水力参数测试——以辛集新城地区为例  

Soil Hydraulic Parameters in Deep Vadose Zone Based on Stable Evaporation——A Case Study in Xinji Area

作　　者：刘亚磊[1] 梁杏[1,2] 林丹[1] 朱常坤[1] 

机构地区：[1]中国地质大学环境学院,武汉430074 [2]中国地质大学生物地质与环境地质国家重点实验室,武汉430074

出　　处：《中国农村水利水电》2013年第10期27-32,共6页China Rural Water and Hydropower

基　　金：国家重点基础研究发展计划"973"项目(2010CB4288-02);国家自然科学基金项目(41272258)

摘　　要：根据垂向一维非饱和流运动的基本原理，利用Ku～pF测试仪在稳定蒸发条件下，对辛集新城地区包气带不同深度（2～14m）的10个原状土样，进行了土壤水分特征曲线及非饱和导水率的测试。将测试结果与VanGenuchten模型及非饱和导水率经验公式进行拟合，求取了残余含水量研，饱和渗透系数K。及经验系数a、n等参数。结果表明：VanGenuchten模型适合拟合研究区的土壤水分特征曲线；研究区土壤非饱和导水率介于10^9～10-4cm／d间，且非饱和导水率与含水量呈指数函数关系；随着深度的增加，包气带土壤结构发生变化，试样的土壤水分特征曲线形状逐渐变陡，非饱和导水率的数值突变特征明显，土壤的持水能力加强。试验表明Ku—pF土水测试仪对于壤土和低容重的粉土测试效果较好。Experiment was carried out on ten undisturbed soil samples from the deep vadose zone in Xinji Area using Ku-pF Apparatus. According to the one-dimension unsaturated Darcy＇ law, soil water retention curve and unsaturated hydraulic conductivity were estimated. By fitting with van Genuehten model and unsaturated hydraulic empirical equation, hydraulic parameters like residual water content, related coefficients a.n and saturated permeability were obtained. The results show that： ①Van Genuchten model is suitable for soil water retention curves of the samples;②the hydraulic conductivity at the range of 10^0 and 10 -4 cm/d decreaseds with exponential function of the water contentl ③the soil hydraulic parameters in deep vadose zone changes with depth because of soil texture, and the retention capacity is strengthened simultaneously; ④it is better to do the measurement on loam and low dry bulk density silt samples using the Ku-pF apparatus.

关 键 词：深厚包气带 土壤水分特征曲线 非饱和导水率K(θ) Ku—pF测试仪 

分 类 号：P641.25[天文地球—地质矿产勘探]