Effects of evaporation and irrigation frequency on soil water distribution

Water distribution in soils with or without evaporation under different irrigation frequencies was investigated through disturbed soil columns in Lab. Results showed that irrigation frequencies could change the spatial distribution and storage of soil water. When irrigation frequency increased with the same irrigation quantity, the soil water content and storage in the upper layer would increase but the wetting front in soil profile became shallow. Results also proved that a suitable irrigation frequency could increase the soil water storage. Evaporation influenced the soil water distribution mainly in the upper soil layer at the initial stages of irrigation. The increasing total irrigation quantity reduced soil water deficit in the upper layer but enhanced such deficit in the lower layer. The higher the irrigation frequency is, the faster it decreases.