RIVER FLOW AND MASS TRANSPORT OF YODO RIVER SYSTEM IN FLOOD CONDITIONS

Abstract

During flood periods, rivers transport large amounts of water and nutrient loads, and have significant impacts on water quality and ecosystems in coastal seas. In order to clarify the runoff characteristics of Yodo, Uji, Katsura and Kizu rivers, field measurements were carried out under the flood condition caused by typhoon no.0918 in addition to ordinary conditions.

The river flows were calculated using the SiO₂-Si concentrations, stable isotope ratios and conductivity readings of water samples along with H-Q formula. Mass transports were also estimated, and the results showed that Uji river has a major influence on Yodo river in the ordinary conditions, while Kizu River become a dominant river among the three upper rivers in the flood condition.