Abstract
This paper describes a water conservation study conducted in two catchments, one in forest and the other in grassland, in Sado, Japan. The investigation characterizes various runoffs of the two catchments. The results show that total outflow of the forest watershed is less than that of the grassland in the no-snow spell. The runoff model is shown to reproduce observed outflow patterns in Sado and this model is a satisfactory method introduced from the verification plots. In particular, the amount of storm runoff from the forest catchment is small. The data suggest that the runoff is uniformed at the catchment area in forest. It is desirable for water resource management that the runoff water is supplied without significant variation. It is expected that afforestation enables the continuously unchangeable water supply.
