本文基于水平一维非饱和土壤水分运动规律,推求了Gardner-Russo持水曲线模型参数,获得了水平一维非饱和土壤水分运动中累积入渗量、入渗率、湿润峰、入渗时间之间的理论关系.用模拟的结果进行拟合,其决定系数为0.9969~0.9997.当获得土壤饱和体积含水率、初始体积含水率、残余体积含水率和土壤饱和导水率,基于这些理论关系实现了Gardner-Russo模型曲线特征参数的求解.利用数值模拟数据和实验数据检验该方法,将用此方法估计的参数值与理论值进行比较,并进行了模型中参数的敏感性分析,结果表明本研究所求得的参数有较高的精度,为土壤水分运动参数求解提供了一种简单的土壤水分瞬时入渗法.
The parameters of Gardner-Russo model for describing the soil retention curves are obtained based on the movement rules of horizontal one-dimensional soil water infiltration. The theoretical relationships among infiltration time, cumulative infiltration, infiltration rate and wetting front are deduced. According to these relationships the parameters of soil water retention characteristic curve of the model can be determined when saturated soil water content, residual soil water content, initial soil water content and saturated soil hydraulic conductivity are obtaiined. The validity" of the proposed method is verified by experimental data and the sensitivity analyses for the parameters are carried out. It is concluded that the accuracy of the parameters determined by this method is fine.