The Laws of Soil Water Movement under the Drip Irrigation

Adopting muctipassway soil water automatic determine system,under the drip irrigation condition water infiltration and redistribution are simulated and determined for air dried sandy soil.According to the determined result,the text analyze characteristics of soil water movement,such as the increased rate of the wetting front,the course of soil water content movement of the characteristic point,soil water distribution during irrigation and soil water redistribution after irrigation in wetting region.The result of test show that soil water content distribution is reduced gradually from center outward,and the water content section possesses the characteristics of triangular form under the point source infiltration.In the course of the soil water redistributions after stopping irrigating,wetting front is passing to the outside constantly,and the soil water content of wetting layer increase in the beginning,and soil water content in the wetting region is generally reduced on later stage,and the region where the soil water is higher shifts down gradually,and soil water content is relatively stable to reach finally.