Sub-theme
6. Innovation for Water Governance and Management
Topic
6-4. Integrated river basin management
Body
The Yellow River water and sediment regulation has been carried out for 23 consecutive years, which has greatly changed the water-sediment process of entering the lower reaches. Many scholars have evaluated the role of the Yellow River water and sediment regulation by reducing siltation in reservoirs and river channels, expanding the flood discharge capacity of the downstream main channel, promoting the stability of the wandering river flow, and ecological water replenishment in the estuary area. This paper highlights the integrity of the river system in the Lower Yellow River and systematically evaluates the multi-dimensional effect of water and sediment regulation on the sustainability of the river system. It is based on the synergistic action of three subsystems (water-sediment transportation, ecological environment and social economy) in the river system, from several indexes such as channel scouring and siltation, channel morphology, ecosystem pattern of downstream river channels and estuaries, ecological and environmental quality, irrigation water scale and crop production. The results show that the basic function of flood discharge and sediment transport in the Lower Yellow River was restored and maintained, the flow capacity of the main channel was stable 4,000 m3/s, and river regime was basically controlled. The ecosystem pattern in the Lower Yellow River and the delta was optimized, the delta wetland and water area increased by 125.82% and 318.54%, and the Saline-alkali land area reduced by 89.65%. The habitat index has been raised to the highest level in nearly 40 years. The irrigation water increased by 31%, and the grain production got a continuous growth for 16 years by 71%. On the whole, the coordinated development level of water-sediment transportation, ecological environment and social economy in the Lower Yellow River was continuously raised from the reluctant coordination level (before water and sediment regulation) to the high coordination level.