裸地斜面域における雨水の浸入と地下水流出(2) ―流出モデルヘのアプローチ―

Abstract

As the first step of the study to approach runoff process in mountain area, hydrographs observedat the outlet of a slope lysimeter were simulated applying the mathematical model composed ofequations of soil moisture movement and groundwater flow.First, the fundamental equations were solved numerically assuming that capillary zone consistsof thin upper and thick lower soil layers. As the result of calculation, it was recognized that thefundamental model could be used to explain the observed hydrographs.Next, the possibility of simplification of the fundamental model was examined utilizing theabove mentioned results. The simplified model consists of co-axial representation of typical factorsrelating to rain infiltration to separate surface runoff component from rainfall and the functionalrepresentation of soil moisture flux by averaged soil moisture content in every soil layer. This modelwas also able to explain the observed hydrographs.