Soil salt crusts greatly reduce wind erosion and PM10 emission on sandy loam

Wind erosion leads to significant loss of soil and soil organic carbon in arid and semi-arid desert ecosystems, posing a serious threat to sustainable agriculture and ecological security. Soil salt crusts (SSCs),¹ widely distributed on soil surfaces in these regions, have a notable impact on surface processes, including the initiation, release, and transport of soil particles. However, there is limited understanding of the role of SSCs in reducing wind erosion and PM10 emission, as well as the surface changes of crust-covered soils during wind erosion. In this study, we used wind tunnels to evaluate the influence of artificial SSCs on wind erosion rate (WER),² surface characteristics, and PM10 emission during wind erosion processes. The results showed that as the salt concentration of irrigation water increased, the hardness and shear resistance of SSCs also increased, the structure became denser, but the thickness decreased. The effectiveness of SSCs in reducing WER and inhibiting PM10 emission also improved with the increasing salt concentrations. Additionally, SSCs delayed and reduced the geomorphological changes in the soil surface during wind erosion. We conclude that irrigation water salinity affects SSC formation, altering the structure and strength of the soil surface. Once SSCs are destroyed, WER and PM10 emissions may increase significantly. Thus, in addition to supporting plant growth, saline water irrigation in arid and semi-arid regions can form soil salt crusts (SSCs) that serve as an effective measure against wind erosion.