| Research on soil moisture movement of drip irrigation, is the right design system and the premise and basis of field crops to high water management. In order to understand the movement of soil moisture and water distribution under drip irrigation through the laboratory test on a single-point source drip irrigation and two-point source drip irrigation. Under the conditions of point source infiltration, this paper studied dripper discharge and dripper water on soil moisture content, shape and range of wetting; Under the conditions of two-point source infiltration, dripper discharge and the effect of soil moisture movement on interference effect of two-point source infiltration. The main results are as follows:1) Through indoor single point source drip irrigation experiments, the results showed that, generally, wetting front is similar to a parabola, and vertical wetting front and horizontal wetting front exist the significantly parabolic relationship. The body of horizontal and vertical sub-humid distance increases with the increase of infiltration time. Through infiltration experiments with different emitter flow, the results showed that, there is a significant power function relationship between horizontal and vertical infiltration distance of wetting drip and infiltration time, and emitter flow rate is the greater the wetting front migration rate the greater. The regular pattern of horizontal and vertical directions rate of wetting front migration is same. Infiltration wetting front movement rate of the beginning is larger. With the infiltration time, the migration rate decreases. What's more, at the same time the vertical infiltration wetting front migration rate is greater than the horizontal migration rate of wetting front.2) Condition in the drip free infiltration and emitter flow is 4.6L/h, vertical wetting front migration speed of change is higher than the level change rate of wetting front movement velocity,which used the shortest time.3) Condition in the drip free infiltration, using the parabolic of moist body shape, wetting characteristic value of the experience of solution model can be calculated. Test data can verify model. The most of relative error is less than 5%. Model has high accuracy. Moist body water content in the horizontal or vertical direction, moisture content near emitter is maximum and with the increasing infiltration distance decreases. In a plane, moisture content close to the same. Distance from the emitter near to far, water content changes from big to small and contour distribution is from sparse to dense.4) In this paper, using the parabolic model of rotating obtained the relationship between wetted soil volume and irrigation water amount. Finally, through the analysis, the dripper discharges was 0.65L/h express the average soil moisture from content to increase. Under the conditions of two-point source infiltration, the dripper discharges was 0.53L/h express the average soil moisture from content to increase.5) In the conditions of point source interference infiltration, the horizontal and vertical movement distance of soil wetting front are increase with infiltration time, and the horizontal and vertical movement distance of soil wetting front accorded good power function relation with infiltration time underside of dripper; but the horizontal and vertical movement distance of soil wetting front accorded good linear relationship on the intersection side.6) In the conditions of point source interference infiltration, under the same irrigation water amount and the same emitter space, when in large dripper discharge, using shorter time when occurs intersection in wetting. In the same emitter flow, the soil moisture of wetting front on the intersection side is bigger than the soil moisture of same depth in single point source infiltration. In the before and after intersection, the discipline of moisture content distribution in horizontal and vertical direction: with the extension of infiltration distance, soil water content gradually decreases.
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