Soil Water Distribution Characteristic and Irrigation Uniformity of Low-Pressure Moisture Irrigation

The watermelon irrigation comparative experiment between moisture irrigation and drip-irrigation is conducted to analyze the soil water distribution characteristic and the irrigation uniformity in different sections and soil layers.The results show that under drip irrigation,the soil water stratified obviously in the vertical direction,the soil water is mainly concentrated in the 0to 40 cm soil layer after irrigation,and the horizontal soil water content gradually reduces with the increase of distance away from the dripper;while under moisture irrigation,in the vertical direction,the soil water content of the layer under the moisture pipe is larger than that of the above layer,the water-supply of moisture irrigation is stereoscopic,the soil water content in the left side of moisture pipe is similar to that in the right side,and the irrigation uniformity is higher;under moisture irrigation,the surface soil layer forms the dry layer as film mulching to decrease the evaporation and enhance the irrigation water use efficiency;during the growth period,the soil moisture dynamic variation of moisture irrigation is smaller in a short time,which lightens the work intensity;the soil water content variance coefficient of moisture irrigation in 0~30cm soil layer is smaller;both the surface soil water content variance coefficients of micro-irrigation and drip-irrigation are larger;the main wetting pattern of moisture irrigation is in the 5~30cm depth soil layer,and the soil water content is uniform in that area;the main wetting pattern of drip irrigation is in the 0~50cm depth soil layer,and the soil water content is uniform in the 10~40cm depth.