The Effect of a Sand Interlayer on Soil Evaporation during the Seasonal Freeze–Thaw Period in the Middle Reaches of the Yellow River

Abstract

Reducing soil evaporation in arid and semi-arid areas of the Yellow River Basin greatly benefits the efficient utilization of water resources in winter and spring, particularly during the seasonal freeze–thaw period. We conducted a field experiment in winter to understand the influences of different sand interlayers (depths of 5, 10, and 15 cm and particle sizes of 0.5–1.5 mm and 2.0–2.5 mm) on soil evaporation during the seasonal freeze–thaw period. The results show that the sand interlayer reduced soil evaporation during the seasonal freeze–thaw period. Decreasing the depth of the sand layer was more effective at reducing the evaporation than increasing the grain size. Soil evaporation reduced as the sand interlayer approached the surface. With constant particle size, total soil evaporation decreased by 40%, 20%, and 18% for sand interlayer depths of 5, 10, and 15 cm, respectively, compared to the homogeneous soil column. With a constant sand interlayer depth, the inhibition of soil evaporation for a particle size of 0.5–1.5 mm was clear. That is significant for improving the efficient utilization of water resources and sustainable development of agriculture in the Yellow River Basin.