Reduced sediment transport in the Yellow River due to anthropogenic changes

The sediment load of China’s Yellow River has been declining. Analysis of 60 years of runoff and sediment load data attributes this decline to river engineering, with an increasing role of post-1990s land use changes on the Loess Plateau. The erosion, transport and redeposition of sediments shape the Earth’s surface, and affect the structure and function of ecosystems and society1,2. The Yellow River was once the world’s largest carrier of fluvial sediment, but its sediment load has decreased by approximately 90% over the past 60 years3. The decline in sediment load is due to changes in water discharge and sediment concentration, which are both influenced by regional climate change and human activities. Here we use an attribution approach to analyse 60 years of runoff and sediment load observations from the traverse of the Yellow River over China’s Loess Plateau — the source of nearly 90% of its sediment load. We find that landscape engineering, terracing and the construction of check dams and reservoirs were the primary factors driving reduction in sediment load from the 1970s to 1990s, but large-scale vegetation restoration projects have also reduced soil erosion from the 1990s onwards. We suggest that, as the ability of existing dams and reservoirs to trap sediments declines in the future, erosion rates on the Loess Plateau will increasingly control the Yellow River’s sediment load.