不同负压灌溉条件土壤水分运移规律研究

发布时间：2019-03-09 19:15

【摘要】：基于室内模拟实验,研究了不同负压(0、-5、-10、-15、-20 k Pa)灌溉条件下土壤水分的运移规律。研究结果表明:不同负压条件下的负压灌溉湿润体均为近似椭球体,其水分入渗量及湿润锋的运移均与时间呈显著幂函数关系(Y=a X~b),相关系数在0.99以上,入渗速率随负压绝对值增大而减小,-5 k Pa处理的渗水速率为对照的80%,-10 k Pa处理为对照的67%,-15和-20 k Pa处理均为对照的57%。湿润锋水平和垂直运移速度随负压绝对值增大而降低,与对照相比,-5 k Pa处理的垂直湿润锋延迟2 d到达箱底,-10 k Pa处理延迟5 d,-15 k Pa处理延迟8 d,-20k Pa处理延迟12 d。土壤含水量变幅随着控制水势下降而增加,下限土壤含水量减小。
[Abstract]:The movement of soil water under different negative pressures (0, 5, 10, 15, 20 k Pa) was studied based on laboratory simulation experiments. The results show that the wetting bodies under different negative pressure conditions are approximate ellipsoid, and the water infiltration and the migration of wetting front have a power function relation with time (Y _ (a) X ~ (?), and the correlation coefficient is more than 0.99, and the correlation coefficient is more than 0.99, and the relative coefficient is more than 0.99. The infiltration rate decreased with the increase of negative pressure. The infiltration rate of-5 k Pa treatment was 80% of that of the control, the 10 k Pa treatment was 67% of that of the control, and the treatments of 15 and-20 k Pa were 57% of that of the control. The horizontal and vertical migration velocity of wet front decreased with the increase of negative pressure absolute value. Compared with the control, the vertical wetting front of-5 k Pa treatment delayed 2 days to the bottom of the box,-10 k Pa treatment delayed 5 days, and 15 k Pa treatment delayed 8 days. -20k Pa processing delay 12 d. The variation of soil water content increased with the decrease of controlled water potential, and the lower limit of soil water content decreased.
【作者单位】：山东省农业科学院农业资源与环境研究所/农业部黄淮海平原农业环境重点实验室/山东省植物营养与肥料重点实验室;
【基金】：“十二五”农村领域国家科技计划课题(2013AA102901) 公益性行业(农业)科研专项(201503130)
【分类号】：S152.7

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