【摘要】 本文研究了重力为非饱和水分运动主要驱动力时,吸附溶质的宏观弥散度与孔隙介质统计特性和水力特性的关系,研究结果表明,宏观弥散度随溶质运移距离的增加而增加,并逐渐趋于一常数,宏观弥散度是土壤含水量、溶质吸附特性以及非饱和土体统计参数的函数,随平均含水量的增加而减少,随平均吸附因子和σ_f~2、σ_a~2λ_f和λ_a的增加而增大.当溶质运移距离很大时,宏观弥散度为非饱和渗透系数的方差和相关距离的线性函数.更多还原

【Abstract】 The effect of the statistical properties and the hydraulic properties on the macrodispersivity is studied for the adsorbing solute transport in heterogeneous unsaturated soil. It is shown that the macrodisper-sivity increases with the incresing solute travel distance and tends to a constant. The macrodispersivity is a func-tion of mean water content , the adsorbing property, and the soil statstical properties. The macrodispersivity in-creases with the decreasing mean water content and increases with the increasing variances and correlation lengths of saturated conductivity and soil parameter α , and mean adsorbing factor. The macrodispersivity is a linear function of the variance and correlation length of the unsaturated hydraulic conductivity when the solute moves a long distance.更多还原