基于信息熵方法的土壤水分入渗方程试验研究

对沙壤土、黏壤土进行水分入渗试验,确定4种熵方程(E-Horton、E-Kostiakov、E-Philip、E-GreenAmpt)系数并标定了一般方程(Horton、Kostiakov、Philip、Green-Ampt)系数。根据所得到的方程计算相应的入渗率,并与试验观测数据进行比较。结果表明:在沙壤土中,E-Horton、E-Kostiakov、E-Philip方程能较好地反映土壤水分入渗规律,E-Green-Ampt方程高估了土壤水分入渗率。在黏壤土中,4种熵方程拟合效果均较差。与一般方程比较,基于信息熵方法的土壤水分入渗方程更适于沙质土壤,因为该方法不需要标定方程的参数,简便可行,而且较好地反映了参数的物理意义,为优化灌溉提供理论依据。

An Experimental Study on Soil Water Infiltration Equations Based on the Information Entropy Method

Based on the water infiltration experiments of sandy loam and clay loam soil,we determined the coefficients of entropy equations (E-Horton,E-Kostiakov,E-Philip,E-Green-Ampt) and general equations (Horton,Kostiakov,Philip,Green-Ampt).Infiltration rates were calculated from these equations,and compared with the data obtained by experimental observations.The results showed that E-Horton,E-Kostiakov,and E-Philip equations were suitable to fit soil water infiltration rates,and that E-Green-Ampt equation over-estimated soil water infiltration rates in sandy loam soil.However,these entropy equations were not suitable to fit infiltration rates in clay loam soil.Compared with the general equations,the entropy equations were more suitable to study infiltration rates in sandy loam soil.Since the entropy equations do not need any calibration parameters,they are feasible to reflect the physical meaning of the parameters and provide a theoretical basis for the optimization of irrigation.