原状土滴灌条件下水分再分布过程研究

在米脂山地微灌枣树示范基地进行原状土的滴灌入渗试验,研究了不同流量、不同灌水历时条件下,水分再分布过程湿润体特征值的变化规律及水分分布规律。试验结果表明,灌溉结束48 h后土壤水分运动达到暂时的平衡,此后土壤含水率变化很小,湿润峰几乎不再扩展;再分布后湿润体体积与灌水量间也存在良好的线性关系;土壤含水率的最大值不在地表而在地表以下10 cm左右深度处;建立了预测湿润体特征值和湿润体体积的经验模型。

Investigation on Undisturbed Soil Water Redistribution under Drip Irrigation

Experiment of water movement of undisturbed soil under drip irrigation was investigated in Jujube demonstration base of mountain micro-irrigation in Mizhi,investigated the effect of different dripper discharge and irrigation amount on the characteristics value of soil wetted volume and the course of soil water distribution during the course of soil water redistribution.The result showed that the movement of soil water achieved the temporary balance in 48 h after stopping irrigation.Subsequently the change of the soil water content became very small,and the wetting front was kept nearly un-expanded.After soil water redistribution,the soil wetted volume conforms to power function of irrigation amount.The maximum value of soil water content is 10 cm below the surface while not on the surface.Some models were presented to predict horizontal and vertical wetting front and volume of wetted soil.