How rain-formed soil crust affects wind erosion in a semi-arid steppe in northern China

• Rainfall quantity affects soil crust thickness.
• Rain-formed soil crust affects wind erosion.
• Soil crusts formed with > 0.5 mm rainfall can completely prevent wind erosion.
• Clay + silt content influences the soil loss ratio after low (.2 mm) or non-rainfall.
• SOC content influences the soil loss ratio after low or non-rainfall.

There have been few studies on the formation and resistance of physical crusts to wind erosion for typical steppe soils in Inner Mongolia, China. The objectives of this study were to 1) examine the effects of rainfall quantity on soil crust thickness, 2) investigate the effects of soil crust on wind erosion, 3) determine the crust thickness (crust formed by various rainfall quantities) able to most effectively resist wind erosion, and 4) evaluate the differences between the responses of soils with different treatment histories to crust formation and subsequent wind erosion at given rainfall quantities. To this end, we simulated five light rainfall levels to investigate the impact of light rainfall on soil crusting and subsequent wind erosion for soils of a semi-arid steppe via a unique approach. The results show that the soil crust thickness increases linearly with an increasing amount of rainfall for all four soils. The soil crust formed by rainfall of more than 0.5 mm was able to nearly completely prevent wind erosion during the experimental period; soil losses of only 0.1–2.4% were observed for the high rainfall treatments (> 0.5 mm) for all four soils. In contrast, soil losses of 9.4–33.1% occurred in the non-rainfall treatments for the four soils. The results show that the soil loss ratio increased with increasing clay plus silt content and SOC content for the non-rainfall treatment and 0.2 mm rainfall treatment.