Dynamic Mechanics of Soil Erosion by Runoff on Loess Slope

摘要

In this research, soil erosion and sediment yield were calculated by runoff shear stress, runoff energy consumption and runoff power theory. Results indicated that a linear relationship existed between the average runoff shear stress and sediment yield. Soil erodibility in the experiment was 178.5g/(Pa·min), and the critical shear stress value was 0.54 Pa. Results from energy consumption implied that there was also a linear relationship between sediment transportation and energy consumption of runoff unit width: Dr= 14.61 (ΔΕ-0.37), which indicated that the soil erodibility was 14.61 g/J, with a critical energy consumption of 0.37 J/ (min·cm). Results from runoff power theory showed that sediment transportation increased with increase in runoff power, and the simple linear relationship was also regressed: Y = 8942.2× - 68.676. Generally, these three theories each showed certain advantages in describing the soil erosion processes on the slope, among which the results from energy consumption theory were simpler, more accurate, and proved more convenient in describing soil erosion on the slope.