Evaluation of habitat quality and ecological flow in a regulated waterway

Abstract Dam control changes the hydraulic environment and hydrological rhythm of rivers; to explore causes fish habitat loss influence river regulation in such rivers, downstream curving reaches Shaying River were cut off. Grass, silver, bighead carp selected as research targets, impact waterway effect gravel mounds on target studied using numerical simulation. The results show that original channel's is similar artificial channel, spawning limited, which an important reason for shortage resources area. reconstructed channel can meet river's navigation demands improve flood discharge capacity. method was used estimate minimum appropriate ecological flows at each growth stage rivers. Under flow, weighted usable area (WUA) juvenile, migratory, habitats increased by 168, 24, 580%, respectively, compared while WUA adult preferred a slow-water decreased 62%, effectively improving fish's environment.