Determination of daily eco-hydrographs by the fish spawning habitat suitability model and application to reservoir eco-operation

• Published in: Ecohydrology 2016-09, Vol.9 (6), p.973-981
• Main Authors: Li, Ruonan, Chen, Qiuwen, Han, Rui, Cai, Desuo
• Format: Article
• Language: English
• Subjects: ecological hydrograph; fish habitat quality; Freshwater; landscape ecology index; reservoir operation; Yalong River
• ISSN: 1936-0584; 1936-0592
• DOI: 10.1002/eco.1695

Global conflict over water has become increasingly problematic. To meet water demands for economic growth in China, a large number of hydro‐projects have been developed and operated, which have significantly altered the natural hydrological regime of many rivers and imposed profound impact on aquatic ecosystems. Conservation of appropriate ecological flow is essential to balance river ecosystem health and economic development. We proposed an innovative method for river eco‐hydrograph determination based on the protection of fish spawning habitat. An integrated hydro‐environmental‐habitat model was developed and applied in de‐watered channels in the middle of Yalong River, China, where water was diverted for hydropower generation. Schizothorax chongi (S. chongi), the dominant and commercial indigenous fish, was selected as the target species. Different from previous research, the impacts of fragmentation and water level variation on fish habitat were analysed in the spawning period. Eco‐hydrographs for different preservation levels of S. chongi spawning habitat were estimated using the developed model, and the suitable one was recommended. Compared with traditional hydrologic and hydraulic methods, the improved habitat method not only determined the ecological water demand of the species more meaningfully but also increased water use efficiency. Copyright © 2015 John Wiley & Sons, Ltd.