Daily Eco-Hydrograph Determination Method Based on Fish Spawning Habitat Simulation

Ruonan Li, Qiuwen Chen, Rui Han, Duan Chen

Tuesday 30 june 2015

14:35 - 14:50h at Amazon (level 1)

Themes: (T) Hydro-environment, (ST) Ecohydraulics and ecohydrology

Parallel session: 6G. Environment - Ecosystem

Global conflict over water has become increasingly prominent. In China, to meet the great demand of water use for economic growth, numbers of hydro-projects have been set up, which alter the natural hydrological regime of rivers, and exert profound impact on aquatic ecosystem. Therefore, an elaborated method of eco-hydrograph determination has been in great necessity for both maintaining river health and maximizing economic benefit. This research put forward an innovative method for river eco-hydrograph determination with fish spawning habitat as the protected objective. An integrated hydro-environmental-habitat model was developed and applied in the water reduced segment due to water diversion generating of Yalong River Big Bend, Sichuan Province, China. Schizothoracinae, the dominated and commercial indigenous fish, was selected as target species. Different from previous research, the impacts of fragmentation and water level variation on fish habitat were analyzed focused on fish spawning period, as well as suitability. Eco-hydrograph for different preservation level of Schizothoracinae spawning habitat was estimated and the optimal one has been recommended according to the developed model. Compared with traditional hydrological and hydraulic methods, the innovative habitat method was not only able to determine ecological water demand of species accurately, but maximize the quantity of water for power generation.