Basic Research on the Prime Runoff Process of Rainfall in a Hillside Slope

1.本文利用坡面蒸渗仪装置，结合土壤水分运动，对坡面蒸发、降雨入渗、地表径流和地下径流过程进行了初步研究。其次，以蒸发量和降雨量为土壤表面边界条件，对土壤水分运动进行了数值计算。根据计算结果，探讨了土壤水分运动与地表径流、土壤水分再分配与地下径流的关系.希尔赛德坡面降雨入渗由于土壤干燥、土壤中的微小动物和根系腐烂等原因，导致土壤中存在大小不一的裂缝和孔洞等大的连续孔隙（大孔隙），从而影响降雨入渗。为了阐明降雨入渗与土壤pH值的关系，本文采用了一种新的降雨入渗模型，并对降雨入渗与土壤pH值的关系进行了研究 ...更多信息 在丘陵坡地上进行了土壤水分入渗试验和土壤调查。结果表明，降雨入渗速率在降雨开始后迅速下降，且最终入渗速率与土壤的主要特性不符，在此基础上建立了模拟降雨入渗的方法。首先，降雨入渗量的土壤含有细大孔隙的模型，结合毛细管内的粘性流和非饱和土壤水流计算。这些计算表明，细的大孔增加5-10倍的水力传导性。接下来，基于以下假设计算渗入含有粗大孔隙的土壤的降雨量：（a）粗大孔隙填充有具有高水力传导性的粗多孔材料。(b)这些粗糙的大孔隙周围的土壤是均匀的和同质的。计算结果与实测入渗曲线吻合较好。少

1. The Runoff Process of Rainfall in Bare SlopeThe process of evaporation, rainfall infiltration, surface and groundwater runoff have been basically investigated in connection with soil moisture movement using the slope lysimeter equipments.First, the energy budget techniques have been used for determining evaporation from the bare slope of lysimeter. Next, the soil moisture movement were calculated numerically using the evaporation and rainfall as boundary conditions of soil surface. On the basis of the calculated results, the relationships between soil moisture movement and surface runoff, re-distributions of soil moisture and groundwater runoff were discussed.2. Rainfall Infiltration in a Hillside SlopeThe presence of large continuous openings (macropores) such as cracks and holes of differing sizes caused by desiccation, tiny animals in the soil and the rotting of roots, affects the infiltration of rainwater to soil.In order to clarify the relations between rainfall infiltration ph … More enomena and macropores, infiltration tests and a soil survey made on the slope of a hilly region. These results indicate that the infiltration rate of rainfall decreased rapidly after rain began, and that the final infiltration rate too large for the prevailing soil character.Based on the results, a simulation method was established and investigated. First, the amount of rainfall infiltrating soil containing fine macropores was calculated from a model that combined viscous flow within the capillary tubes and unsaturated soil water flow. These calculations showed that fine macropores increase the hydraulic conductivity of the 5-10 fold. Next, the amount of rainfall infiltrating soil containing coarse macropores was calculated based on the following assumptions: (a) The coarse macropores were filled with coarse, porous material of high hydraulic conductivity. (b) The soil around these coarse macropores was uniform and homogenerous. The calculated results agree well with the infiltration curve obtained from field tests. Less