Evaluation of suitable hydraulic conditions for living environment of fishes with horizontal 2-D numerical simulation and PHABSIM

Abstract

Before river improvement work, it is necessary to conduct the environmental assessment. However, the accuracy of the environmental assessment is not so high, because the preference curves of the flow depth, velocity and so on have been not clear. Recently, the preference curves of the flow depth, velocity and substrate concerning with Zacco platypus, Zacco temminckii, Tribolodon hakonensis and Rhinogobius flumineus are suggested by Komura. In this study, the living environment of those fishes in Gokasegawa River is predicted on the basis of preference curves suggested by Komura. Further, environmental characteristics were compared. As a result, the most suitable cross section was suggested.