ABSTRACT
In the loess hilly-gully region covered with sheet sand, soil water erosion processes are different than those for the typical loess hilly-gully region because of the natural environment and loose land surface material. New and unusual water erosion processes were observed during rainfall simulation studies on a typical slope in the Shenmu experimental area situated in the 0.89 km'2 Liudao gully. These processes were (1) for the slopes with sands, runoff rate was lower and runoff silt content higher and gullies were formed by the processes of infiltrationinterflow-collapse; (2) for the slopes with sand-loess and loess, the major factors of water erosion were the rainfall intensity and rainfall amount of annual first rainfall; and (3) the evolution process of the slope gully system results from alternative actions of sand deposition and water erosion in this region.
