Ecological Operation Practice of Artificial Flood Peak for Fish Spawning -- Taking the Lower Jinsha River-Three Gorges Cascade Reservoirs as an Example.

From 2011 to 2023, a total of 20 ecological operation experiments of artificial flood peak were conducted in the Lower Jinsha River-Three Gorges cascade reservoirs, focusing on the fish spawning, and a lot of experience was accumulated while achieving good experiments results. In order to systematically figure out the effectiveness and experience of the ecological operation experiments of artificial flood peak over the years, this paper takes the Lower Jinsha River-Three Gorges cascade reservoirs as an example. First, the principles, key points, monitoring and evaluation methods of the ecological operation experiments of artificial flood peak were introduced. Second, the development of operation experiments over the years was reviewed. Finally, the operation experience was summarized and the future optimal direction was proposed. The results showed that the ecological operation experiments of artificial flood peak in the Lower Jinsha River-Three Gorges cascade reservoirs effectively promoted the spawning of fishes spawning drifting eggs in the Yangtze River. The effect of promoting the natural spawning of the representative fishes spawning drifting eggs--the four major Chinese carps under the dam is the most significant in the Three Gorges Reservoir. By 2023, the total spawning scale of the four major Chinese carps in the middle reaches of the Yangtze River reached 38.25 billion. Under the joint promotion of multi-year ecological operation practice and 10-year fishing ban plan, the fish resources of the four major Chinese carps is close to the level of the 1980s. However, under the influence of climate change, fish spawning and developmental characteristics change, spawning ground change and other factors, the ecological operation experiments of artificial flood peak need to carry out targeted optimization and adjustment in the aspects of operation process optimization, operation effect evaluation, and operation effect improvement. The results can provide a reference for the ecological operation of artificial flood peak for fish spawning in similar basins under changing environment. [ABSTRACT FROM AUTHOR]