含砾石土壤降雨入渗过程模拟

Simulation of rainfall infiltration in stony soil

在室内模拟降雨试验的基础上,利用多重相互作用连续体(MINC)组件,对含砾石土壤降雨入渗过程进行了数值模拟,以期深入理解含砾石土壤中的水土过程。研究结果表明,土壤中砾石的存在能够导致土壤水分饱和度增加,使得土壤总入渗量以及降雨入渗深度降低。含砾石土壤中存在一个陡的湿润锋面,在湿润锋面上土壤水分饱和度急剧下降。MINC组件可以很好地模拟含砾石土壤降雨入渗过程,其对含砾石土壤湿润锋和土壤含水率变化的模拟值与实测值吻合较好。降雨期间土壤水分饱和度沿土壤剖面的变化可用来解释含砾石土壤降雨入渗深度降低的原因。

Based on the laboratory rainfall experiments, the process of rainfall infiltration in stony soil is numerically simulated using the multiple interacting continua (MINC) method. The objective of this study is to further improve our understanding on water movement in stony soil. The results show that the maximum water saturation of soil can be increased if gravels present, while the total amount of infiltrated water and the infiltration depth in soil would be reduced accordingly. There is a steep wet front in the stony soil column, the maximum water saturation of soil decreases sharply along the front surface. The process of rainfall infiltration is well simulated by the MINC model. Both simulated wet front and soil water content close to the observation. The reduction of rainfall infiltration depth in stony soil can be attributed to the change in the maximum water saturation of soil along the soil profile during a rainfall.