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采用渗透仪法和非稳定流的水平土柱法研究了四川丘陵区泥页岩母质发育的紫色土的一维饱和与非饱和流的运动特征。结果表明,不同土壤的饱和导水率差异甚大,变化范围为8.03×10~(17)～2.96×10~(14)cm/s.表土层饱和导水率高于心土层,平均相差5倍,高的近1个数量级.影响饱和导水率的主要因素是土壤结构.紫色土的一维非饱和流的运动受土壤质地和孔隙度的制约,质地愈细、孔隙度愈小,在相同时段内的水平入渗量愈小,水扩散范围愈窄。水扩散率D(θ)与土壤湿度(θ)之间的关系可拟合为D(θ)=Ds(θ/θs)~α.不同土壤的D_s 值相差可达2个数量级,随着土壤粘粒含量的增大,Ds 值呈指数升高.
A one-dimensional saturated-unsaturated flow model of purple soil with shale parental material in the hilly area of Sichuan Province was used to study the characteristics of one-dimensional saturation and non-saturation flow of the purple soil by using permeation and unsteady flow. The results showed that the saturated hydraulic conductivity of different soils differed greatly, ranging from 8.03 × 10 ~ (17) to 2.96 × 10 ~ (14) cm / s. The saturated hydraulic conductivity of topsoil was higher than that of the core soil, with an average of 5 Times higher and higher nearly one order of magnitude.The main factor affecting saturated hydraulic conductivity is the soil structure.The movement of one-dimensional unsaturated flow of purple soil is controlled by soil texture and porosity, the finer the texture, the smaller the porosity is, The smaller the horizontal infiltration in the same period of time, the narrower the range of water diffusion. The relationship between water diffusivity D (θ) and soil moisture (θ) can be fitted as D (θ) = Ds (θ / θs) ~ α.Different soil D_s values differ by up to two orders of magnitude, Clay content increases, Ds value increased exponentially.