The Effects of Wind Erosion Depending on Cropping System and Tillage Method in a Semi-Arid Region

Abstract

Wind erosion is a major environmental problem in arid and semi-arid regions, where it has significant impacts on desertification and soil degradation. To understand the effects of cropping systems and tillage methods on the reduction of soil wind erosion, wind tunnel investigations were performed on soil samples from an irrigated field in an experiment conducted in semi-arid northwestern China in 2016–2018. Three cropping systems for annual spring wheat (Triticum aestivum L.)/maize (Zea mays L.) strip intercropping (W/M), a two-year wheat-winter rape-maize rotation (WRM), and a two-year wheat-maize rotation (WM)) were each evaluated with two tillage methods (conventional tillage without wheat straw retention (CT) and no-tillage with 25–30 cm tall wheat straw (NT)). The mean rate of soil erosion by wind with NT was 18.9% to 36.2% less than that with CT. With increasing wind velocity, the rate of soil erosion by wind increased for both CT and NT but was faster with CT than NT. Soil wind erosion occurred with a wind velocity ≥14 m s⁻¹, and NT greatly decreased the rate of soil erosion when wind velocity exceeded 14 m s⁻¹. W/M, WRM, and WM with NT increased non-erodible aggregates by 53.7%, 53.7%, and 54.9% in 2017, and 51.3%, 49.6% and 44.6% in 2018, respectively, than conventional tillage. At a height of 0–20 cm, the rate of soil transport with CT decreased with increasing height. The volume of soil transport at a height of 0–4 cm and soil transport percentage at a height of 0–4 and 0–20 cm (Q_0–4/Q_0–20) with NT were less than with CT. These findings show that NT with cropping system intensification can be an effective strategy for resisting wind erosion in irrigated semi-arid regions, thereby reducing the negative environmental impacts of crop production.