Review of studies on the water requirement for sediment transport of the lower Yellow River

This paper reviews recent developments in study on water requirement for sediment transport in the Lower Yellow River,including the calculation method,the difference between flood season and dry season,the impact of reserwir operadon,and the required annual water consumption for sediment transport.Results of this study show that the required water consumption is not only related to the discharge and sediment concentration of the incoming flow,but also to the aggradation/degradation condition of the river bed.The water requirement differs during different periods in the year,that is,it is the smallest in the flood sewn,more in the non-flood season,and then the winter menths and the ice flood sewn in turn.Flow and sediment regulated by the reserwirs can effectively change the water requirement for sediment transport.It is suggested that the main method of high-efficiency,watersaving sediment transport in the lower Yellow River is the coordinatedoperation involving several reserwirs,with the Xiaolangdi Project releasing channel-forming discharge and high-concentration flow into its downstream sections,which can reduce sediment deposition in the Lower Yellow River reaches.This paper also lists a number of issues for further investigation.