To clarify the effects and mechanisms of the solution formed by mixing flaxseed meal powder with water on soil water movement in sandy land, this study conducted laboratory simulation experiments using three extraction forms of flaxseed meal solution (supernatant, suspension, and precipitate) and five application rates (5 kg·m−2, 8 kg·m−2, 11 kg·m−2, 14 kg·m−2, and 17 kg·m−2), with untreated aeolian sandy soil set as the control (CK). The results showed that: (1) Flaxseed meal can significantly reduce the soil water infiltration rate, with the sediment treatment group exhibiting the optimal effect. After the application of the three flaxseed meal treatments, soil infiltration indices decreased significantly, and the magnitude of the reduction became more pronounced with the increase in flaxseed meal application rate. (2) Flaxseed meal exhibited a significant effect on water retention and evaporation inhibition; after continuous evaporation for 35 days following the spraying of different flaxseed meal treatments, the cumulative evaporation of CK was significantly higher than that of the other treatments. Compared with CK, the cumulative evaporation of the groups treated with the supernatant, suspension, and precipitate of flaxseed meal solution decreased by 11.69%, 24.13%, and 43.22%, respectively. The sediment group achieved the optimal effect, and the evaporation inhibition effect was enhanced with the increase in application rate. (3) All three flaxseed meal mixture treatments increased soil bulk density and decreased soil total porosity, and saturated water-holding capacity and minimum water-holding capacity, with the sediment treatment exerting the most significant effect. The efficacy of all treatments became more notable as the application rate increased. There was a highly significant correlation between soil physical properties and water movement rate. Flaxseed meal affects soil water movement by altering soil physical properties. In conclusion, spraying flaxseed meal on the surface of sandy soil can effectively reduce infiltration and inhibit evaporation, with the sediment treatment group achieving the optimal improvement effect. The soil crust formed by flaxseed meal has a strong water-binding capacity, which can maintain water supply for plant growth over a long period, making it highly suitable for popularization and application in sandy farmland.
Liu et al. (Sun,) studied this question.