Research on optimal spatial allocation of sediment in main channel of Yellow River(II)—potential and capacity

By means of data analysis and mathematical model,the potential and capacity as well as economic index of sediment spatial allocation in the main channel of Yellow River for various flow and sediment conditions before 2050 are studied.The results indicate that the capacity of sediment transportation for the main channel of Yellow River is large enough to transport sediment about 346-624 million tons per year at Lijin Station in the period from 2008 to 2050,and the potential of creating land in estuary is about 2.54 billion tons,the annual capacity of transporting sediment into deep sea is about 174-257 million tons.The capacity of sediment transport should be fully utilized to create land in estuary and transport sediment into deep sea.The potential of reservoirs for storing sediment in main channel and tributaries is also large enough to store sediment about 5.31 billion tons.The annual capacity of the Xiaolangdi Reservoir is 507-594 million tons,and the annual capacity of Guxian Reservoir is 342-545 million tons.Because the volume of reservoirs for storing sediment is limited,it should be utilized reasonablely to improve the siltation in the river channel.The potential of river beaches for releasing siltation is also large enough to store sediment about 1.92 billion tons.The annual capacity of beaches in the Lower Yellow River is 34-64 million tons,the annual capacity in Little North Main River is 107-142 million tons,and the annual capacity of Wenmeng beach is 43-106 million tons.The capacity of beaches for releasing siltation is conditional,so it should be utilized reasonablely to improve the sediment distribution in river channel and beaches.The economic index to transport sediment into sea is less than that to store sediment in reservoir,and the economic index of beaches for releasing siltation is higher than that of storing sediment in reservoir.