Effects of Soil Crusts and Tillage Treatment on Soil Erosion in the Loess Plateau of China

The objective of this laboratory study was to assess the effects of soil crusts and tillage treatments on soil erosion in the Loess Plateau of China. The simulated rainfall storms at 40 mm/h, 60 mm/h and 80 mm/h rates were applied to the soil boxes set to a 17.6% slope, two soil surface conditions (crusted and uncrusted soil surface) and two tillage types (contour tillage and straight slope) were used to investigate the resulting runoff rate and sediment yield. Results show that the runoff rates were greater and total soil loss was lower in crusted than uncrusted soils. Contour tillage treatment resulted in smaller runoff rate and total soil loss than straight slope treatment. Rainfall intensity, soil crusts and tillage treatments had very significant (p < 0.001) effects both on total runoff yield and soil loss. The combined effects of rainfall intensity and tillage treatment on total runoff yield and soil loss were much more significant (p < 0.01) than the other combined effects (p < 0.05). Rainfall intensity had a greatest correlation with the total runoff yield while tillage treatments had a greatest correlation with the total soil loss. As a result, the tillage treatments in the Loess Plateau can reduce the impact of soil crusts on soil erosion effectively.