In loess hilly-gully region covered by sheet sand,soil water erosion process is different from typical loess hilly-gully region because of worse natural environment and loose land surface material.

• 在片沙覆盖的黄土丘陵区，由于恶劣的自然环境及松散的地表组成物质，土壤的水蚀过程明显地不同于典型的黄土丘陵区。