内蒙孪井灌区包气带土壤水分特征研究

摘要

Measure the soil pressure head and the weight of the soil samples with the ku-pF Apparatus are measurod, which can record the process of soil desorption and get the soil water characteristic curves (SWCC). The SWCC is fit with the van Genuchten Model and its revised Model and the fitting value to the measure value is compared. The results show that van Genuchten Model can simulate the different kinds of soil in Luanjing Irrigation Area better than the revised Model. The top sandy loam in Luanjing has the similar SWCC. The research also shows that in the surface soil the bigger the ratio of clay is, the higher the residual water content raises,while the saturated water content are the same.%采用非饱和导水率仪测定了内蒙古孪井灌区土壤样品的负压值和含水量变化,该方法能够完整记录土壤脱水过程,得到土壤水分特征曲线.根据van Genuchten模型及其修正模型对土壤水分特征曲线进行拟合,并比较2种模型其拟合值与实测值的差异.研究结果表明,van Genuchten模型能更好的拟合孪井地区的各种土壤,表层砂壤土水分特征曲线形状相同;另外,表层土饱和含水量相近,黏粒含量越高,土壤的残余含水量越大.