Suitability curves of fishes for riverine habitat evaluation

When we control riverine environment, evaluation of habitat is necessary. In this study, our target is fish habitat. PHABSIM is popular and useful method, but there are several difficulties to apply it to actual rivers. Especially in Japanese rivers, the slope of river bed is very steep, and rilffle and pool are repeated in short distance. So it is difficult to express the river environment. The riffle and pool are quite important for fish habitats, but quantitative classification is still incomplete. So if we estimate the fish habitat, we must quantify the riffle and pool system. But now quantitative factors are only depth and velocity, and used independently. In this thesis, we improved suitability curve which gives the imformation of fish habitat in PHABSIM. The new features are presented as next two points.