Comparison of runoff caused by rainfall and snowmelt in a mountanous small basin

Abstract

The runoff processes throughout a year including rainy and snowmelt season in two small neighbouring basins are studied. The obtained results are as follows:(1) It is shown that river runoff is composed of several runoff components from different vertical soil layers in a slope by using absorbance of ultraviolet 260nm as an index of water quality, also that they are sensitive to accumulated rainfall or rainfall intensity.(2) Geographic effects on runoff characteristics including runoff coefficient, peak discharge and the relation between accumulated rainfall and runoff are clarified.(3) A synthesized numerical model of runoff is proposed and applied to each basin in order to verify the serveral results of the field observation stated above.