Experimental study on the spatial variation of hydrodynamic parameters for hillslope-gully side erosion system in loess landscapes

Abstract. On the Chinese Loess Plateau many hydraulic parameters related to soil erosion are highly variable and often cross-correlated. Hillslope-gully side erosion systems are widespread on the Loess Plateau, but the quantification between the hydraulic parameters is still unknown for the system. A constant headwater scouring experiment in the laboratory was performed in this study and combined a model with two slope segments (with hillslope and gully sides). Five inflow rates of 6, 8, 10, 12 and 14 L/min were used. Some hydraulic parameters (the flow velocity, shear stress, unit stream power, Reynolds Number, Froude Number, Darcy-Weisbach friction factor, and Manning coefficient) were analysed. Regression equations were developed for the parameters. The results provide a basis for in-depth research regarding the erosion processes of hillslope-gully side erosion systems.