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The layered structure of the soil and water repellency affect soil water movement, thereby affecting agricultural production and environmental protection. Layered structure prevalent in agricultural soils. Abroad for more water repellent soil, although in recent years the domestic Xinjiang, Inner Mongolia and other regions has started to carry the water repellency of the soil, but the overall domestic moisture in water repellency sandwich soil in migration law very little, and the small amount of research is not systematic. This article by Interlayer Position on three, four types of water-repellant grade two kinds of layered soil the evaporation test under ponded infiltration test, and six kinds of plastic mulch conditions of one-dimensional analysis of layered water-repellant Soil Water Movement . To further explore the water repellency of the variation of the soil profile and its relationship with soil water and salt content, pH, new Ken drip irrigation in Xinjiang cotton fields to 10cm × 10cm and 5cm × 5cm grid spacing collected two soil samples , the physical and chemical properties of soil spatial variability and correlation analysis. The main conclusions are as follows: (1) Whether it is sand sandwich, or clay interlayer of water infiltration blockade. Interlayer Position sandwich can affect the permeability reduction effect. Folder stratigraphic depth there is a critical value, the folder layers bit 5cm, 10cm and 20cm three cases from the soil surface from the soil surface 10cm clip layers reduced infiltration strongest. (2) Sand Layered different degree of water-repellant loess soil, infiltration, cumulative infiltration and wetting front to advance distance was good exponential relationship, before infiltration front reaches the Sand Layered, Kostiakov formula can better describe the stages of soil infiltration characteristics of water-repellant, repelling water loess soil, moisture into the coarse layer, cumulative infiltration by the nonlinear change over time into a linear relationship between the water repellency of loess soil, unstable linear law. Has the clay interlayer sand infiltration process, the interlayer water repellent extent, the stronger, the slower the infiltration; the coarse layer water-repellant Lou soil and sand with Lou Soil water repellency dissection cumulative infiltration with wetting front advancing distance relationship can be used polynomials. (3) dissection of the lower water evaporation plays a hindering more shallow depth of dissection, hindering the more obvious. The coarse layer folder sticky layer of water blocking performance of the role is not the same. The case of loam cover sand, gravel layer after arrival interlayer in the evaporation surface showed the waterblocking role; under the the sand cover Loessial situation, sandwiched adhesive layer from the evaporation beginning to exhibit the water-blocking effect. Interlayer Position the deeper, different plastic mulch under the conditions of the upper soil moisture content greater the difference. (4) whether the loess soil, folder sand, loess soil, or sand folder cumulative evaporation increases with the increasing rate of plastic mulch. The plastic mulch rate greater than the impact of the evaporation of soil moisture in the mezzanine above the mezzanine soil, the smaller the opening rate, the greater the moisture content of the soil profile. (5) in the same case a film opening ratio, soil repellency, the stronger, the smaller the cumulative evaporation. Evaporation of the loess soil, coarse Sand Layered over Lou soil moisture by plastic mulch rate impact is relatively large; the coarse layer moisture upper loess soil, water repellency enhancement increases; coarse layer below by soil double inhibit evaporation of water repellency and mezzanine small. (6) The smaller plastic mulch rate, the same mezzanine position under the conditions same depth of soil the higher the temperature, the better the warming effect of the coating. The cooling rate of more than 30cm depth soil with increasing depth below 30cm depth soil changes with depth smaller. (7) The exclusion of water small mound of soil in the presence of coarse layer logarithmic model and power model can better describe the evaporation time and cumulative evaporation. The smaller level under the conditions of the same water-repellant, plastic mulch rate (≤ 0.69%) when the power model is superior to the logarithmic model, large plastic mulch rate logarithmic model superior to the power of the model; presence of loess soil, sand dissection cases, loess soil, mezzanine is not water-repellant and strong repelling water power model is superior to the logarithmic model; the Loess soil mezzanine weak water-repellant and serious water-repellant logarithmic model better than the power model. (8) the secondary salinization of soil profile water repellency was moderate variability; soil water repellency 40cm deep near the strongest in more than 80cm depth of soil water repellency characteristics not obvious; 0 ~ 40cm depth of soil, moisture content rate and soil water repellency is related to the depth and water repellency of 40 ~ 80cm negative correlation; salinity addition to the positive correlation in the surface layer and the water repellency of the 0 ~ 10cm, in the remaining soil are negatively correlated; pH value and water repellency between the mostly positive correlation.
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