Current situation and scientific challenge of soil and water erosion in Gully Consolidation and Highland Protection Project of DongZhi Loess Plateau

Due to the influence of extreme rainfall and high intensity human engineering activities, the advance speed of the gully head in the Loess Tableland is intensified, which seriously threatens the economic and social development of the Loess Tableland. In recent years, although large-scale Gully Consolidation and Highland Protection (GCHP) projects have effectively inhibited the development of traceable erosion on Loess tableland, there are still serious problems of soil and water erosion. Based on this situation, this study investigated and analyzed the soil erosion diseases of the typical GCHP Projects through field investigation, literature review, and comprehensive analysis. The results show that the hydrology regulation function of GCHP Projects can be divided into the table-land intercept area, gully head cut row area, gully slope cutting line of energy dissipation, and channel held area. Currently, the GCHP suffers from surface water erosion, subsurface erosion of loess engineering geological interface, blockage of drainage channels, and disaster chain of loess gully. The unclear hydrological control mechanism and the mechanism of soil and water mutual feeding erosion disasters are the key scientific challenges of the project. In the future, attention should be paid to the application of biological soil crust, new soil improvement materials, and the complete quality supervision of gully protection tableland engineering. This study can provide basic information for future research on the mechanism of soil and water erosion disasters and engineering planning and design of the Gugou Plateau.