在来魚類の遊泳能力算定と農業用水路網の避難場所における個体群行動

抄録

Relation between enviromnental structures and fish habitat were compared in a small channel for agricultural irrigation system in a branch of the Neo River in Gifu Prefecture. In general, for hydraulic channel design, sustained speed and burst speed have characterized the swimming ability of fish. In this study, it is conducted to evaluate sustained speed in a non-uniform flow channel. Typical swimming curves of twelve species were evaluated in this experiment. Chaos fractal characteristics of fish movement were estimated in small tank. Biological signals have chaos fractal characteristics and chaos fractal analysis is effective to understand that complexity. It is verified the existence of the chaos characteristics in the movement locus of a fish by means of Lyapunov analysis. Furthermore, the complexity of that movement locus was quantified by means of the fractal dimension analyzing methods. This study suggests the necessity of analysis with the long time observation data to understand further real fish movement.