Why is the Yangtze River less silty than the Huang He?

The Yangtze River is significantly less silty than the Huang He primarily due to differences in the terrain through which they flow.1

A major factor is that the Huang He flows extensively over the Loess Plateau, which consists of loess—a wind-deposited soil that is highly susceptible to erosion. In contrast, the Yangtze flows over very little loess. Furthermore, the floodplains along the Yangtze are more heavily vegetated and less prone to erosion than those of the Huang He.213

While the Yangtze still carries a massive volume of sediment to its mouth—ranking among the highest in the world—its lower silt concentration relative to the Huang He is a direct result of these differing geological and environmental conditions.1