The effect of the coarse aeolian sand on siltation of the Inner Mongolian Reach of the Yellow River

. The Yellow River flows through an extensive, aeolian Inner Mongolian plateau with a total length of 673 km. Owing to the high erodibility of the Wulanbuhe and Kubuqi deserts and the impacts of its upstream reservoirs, the siltation of the Inner Mongolian Reach of the Yellow River is caused essentially by the aeolian particles larger than 0.1 mm, which are very different from the sediment (>0.05 mm) of the lower Yellow River coming from the loess plateau. During the period 1954–2000, the total accumulated sediment of this area was about 20.1×10 8 t, the coarse sediment larger than 0.1 mm (AS) about 15.2×10 8 t, and the fine sediment less than 0.1 mm (FS) about 4.9×10 8 t. In particular, there was 6.1×10 8 t AS coming from the Wulanbuhe Desert, and 5.82×10 8 t AS from the Kubuqi Desert deposited in the river channel of the Inner Mongolian Reach, representing 78.6% of the total coarse sediment larger than 0.1 mm.