滴灌土壤湿润体影响因素的实验研究

在实验室内模拟研究了不同滴头流量、土壤初始含水率和容重条件下,粘壤土点源入渗土壤湿润体水平扩散半径和竖直入渗深度的变化规律。实验结果表明:初始含水率和容重对土壤湿润体特征值有较明显的影响;在供水量一定的条件下,滴头流量对点源积水入渗土壤湿润体特征值没有明显影响;湿润体形状和大小受灌水量的影响比受滴头流量的影响要大。另外对多滴头交汇入渗条件下湿润体特征值进行了初步研究,结果表明交界面处水分的水平扩散和竖直入渗速率大于点源下的入渗速率,随着入渗时间的延长湿润体的形状也逐渐由椭球体向平行于毛管的带状分布过渡

Experimental Study on Factors Effecting Soil Wetted Volume of Clay Loam Under Drip Irrigation

A series of experiments about the effect of discharge rate, soil bulk density and initial soil water content on soil wetted volume of clay loam soil were caried out in laboratory. The experiment result showed that soil bulk density and initial soil water content significantly affected the soil wetted volume; while the discharge rate did not. The shape and size of the wetted volume were more effected by the amount of water applied than that by the discharge rate. In case of interfered infiltration, the infiltration rate at interface was quicker than that in point source infiltration, and the soil wetted pattern on soil surface became a strip shape, which paralleled to the lateral.