Author(s): Shiming Li; Keyan Xu; Dongliang Yuan; Yuanlu Gong
Linked Author(s):
Keywords: Yellow River; Fluvialprocesses; Density current; Regulating sediment and runoff
Abstract: The regulation of runoff and sediment is to use reservoirs’storage and discharge at the right moment, to find out a kind of suitable runoff and sediment proportion. Under the condition of fully using sediment transport capacity of the river course, adjusting natural movement of sediment and runoff can make runoff and sediment transport as marching as possible and put the sediment into Bohai Sea. Therefore, the experiment to regulate runoff and sediment of Yellow River for the first time on a large scale was carried in July 2002. Based on analysis of the 5 million data sets collected during the experiments, we can reach the conclusions as follow: (1) The river course is silted up seriously at earlier stage, the main channel is withered, the over-floodplain discharge is reduced and the discharge ability of the river course is reduced to a large extent. After the flood overflowed the floodplain, the average velocity of flood deduced sharply, which leads to the propagation time of flood to lengthen. In recent 20 years at various stations, the water levels are raised year by year and the discharge ability is weakened year by year. (2) Sedimentation in Xiaolangdi Reservoir from 17th June to 18th July should be 183 million t with the method of sediment load difference, but the sedimentation in the same period with the method of cross-section change is only 144 million t and is 39 million t less than that with the method of sediment load. (3) In the period of regulating the runoff and sediment, the runoff and sediment load are 2,944 million m 3 and 32. l million t respectively at Huayuankou station, but the runoff and sediment into the sea are 2,251million m 3 and 53.1 million t respectively. In the reaches from Xiaolangdi to Dingzilukou with the total length of 818 km, the sediment load eroded from the riverbed is 21 million t with the method of sediment load difference under the circumstances of runoff loss of 693 million m 3.
Year: 2004