Huai River Basin is a unique area owning the largest population density, frequent water disasters, and most serious water pollution in China. Currently, more than 11,000 dams and sluices have been constructed to control flood and relieve drought. The dams and sluices played a very beneficial role in flood control, irrigation, water supply and so on. Whereas, the regulation of dams and sluices changed the flow regimes dramatically and the pollution load discharged to rivers rose year by year, which caused the effect of water environment. It has drawn more attention at home and abroad. At present, the technological problems are: what is the relation and link of basin hydrology-water quality-river ecological variation? The key technology for impact analysis based on basin hydrologic cycle was deficient. How to identify the effects and contributions of dams and sluices on river water environment? Moreover, the current theories and methods for researching the dams and sluices’ affect were weak. 

Prof. XIA Jun and his research team, the Institute of Geographic Sciences and Natural Resources Research (IGSNRR), CAS, have been focusing on the observation and analysis on the impacts of dams and floodgates in Huai River Basin on water environment and ecology variation over the years. The interaction relations between the regulation of dams and floodgates and hydrological variation, water quality variation have been found, and a distributed water quantity-water quality model coupling with dams and floodgates has been developed, which can quantify the effects and regulation capacity of dams and sluices on river hydrology and water quality under different regulation, and provide the key technological support for union “water quality-quantity” regulation of dams and sluices, and ensure the social, economical and ecological water use, and solve the kernel problem of dams and floodgates group’s impacts on river water environment in Huai River Basin.

The research results have been applied to the union “flood control-pollution prevention dispatch” of dams and sluices in Huai River Basin and water resources departments and environmental protection departments in Anhui, Henan provinces and so on. The achievements have been awarded the Second Science and Technology Prize of Anhui province in 2009. Moreover, 5 SCI and another international journal papers have been published.