 The study examined the effects of interlayer on the temperature of freeze-thaw soil and the transformation between freeatic water and soil water in shallow groundwater areas. It found that the presence of an interlayer significantly reduced the rate of upward migration of freeatic water into soil water during the freezing process. Furthermore, the interlayer also slowed the rate of downward migration of soil water into the freeatic layer during the thawing process. This resulted in less efficient loss of groundwater and greater storage of water in the unsaturated zone. This article was authored by Junfeng Chen, Jiaming Ren, Birching Wang, and others.