山地試験地における降雨流出の観測(第2報) ―浸透と流出のメカニズム―

Abstract

Measurement of soil temperature, soil moisture, and infiltration capacity was carriedout at a small plot from 1963 to 1965 besides the observation of raifall and runoff. Itwas found that the litter layer creates runoff in the form of a flow of filmy waterwhich runs downhill along the surface of litters, and that its quantity is proportional tothe rainfall intensity untill it reaches the limit of 15 g/min. About 91 % of the rainfallinfiltrates from the humus layer down to the sandy clay layer, and the remaining 9 %becomes a subsurface flow through the litter layer and the humus layer over the widerange of the rainfall intensity from zero to 1800 JL/min. It was estimated that the rateof infiltration is proportional to the detention above the interface between the humuslayer and the sandy clay layer.