Brief discussion on the water-sediment regulation in the Ningxia-Inner Mongolia reach of the Yellow River under the changing environment

Abstract

The effective reservoir sediment regulation measure is extremely significant for the sedimentladen river. It should not only extend the reservoir life, but also pose favorable conditions for the management of the river-reservoir system. Especially, the remarkable changes in the hydrological processes challenge to the system in some respects, like flood control, rive training, ecological environment improvement and so on. This paper gives a brief discussion on the representative existing problems in Ningxia-Inner Mongolia reach of the Yellow River. The water-sediment parameters and artificial regulation factors are then summed through a comprehensive literature review. Then we investigate the response to the different scales of floods in the Inner Mongolia reach through a three-dimensional model, in which the simulation region is from Bayangaole gauging station to Toudaoguai gauging station. With respect to the riverbed deformation, it is effective to control the relationship between the incoming water and sediment to restrain the shrinkage of the main channel; and surely that there exists a nonlinear relationship between channel scouring and incoming water-sediment conditions. Through data analysis and simulation results, the response characteristics of different watersediment regulation boundary conditions can be obtained, such as the ratio between sediment concentration and discharge, the discharge duration and the discharge, which is favorable to further water-sediment regulation of the reservoir and the management in Ningxia-Inner Mongolia reach of the Yellow River.