灌水量对膜孔灌农田水分运移分布和动态变化影响研究

通过室外测坑灌溉试验,分析了灌水量对膜孔灌玉米不同生育时期的土壤水分运移分布和动态变化的影响。研究表明,灌水后第1天,土壤含水率以膜孔为中心呈等值线分布,土壤水分在再分布过程中出现交汇情况,交汇后土壤水分向更深度方向运移;随着生育时期的递进,膜孔中心附近的土壤含水率逐渐减小,土壤含水率在膜孔中心处最小,随着距离膜孔中心距离的增大而增大;不同灌水量对作物吸收水分后水分分布影响明显,相同深度处,灌水量越大,土壤含水率越大;玉米耗水量随灌水量增大而增大,耗水量和灌水量之间存在显著的幂函数关系。

Effect of Irrigation Minima on Soil Water Transport and Distribution under Film Hole Irrigation

Though the different irrigation minima experiment made under film hole irrigation in the testing-hole,the soil water transport and distribution under different growth period was determined.The result showed: the distribution curve of soil water content is isoline on the first day after irrigation,then soil water interferences after redistribution and transports to the deeper place;soil water content decreases with the growing period near the film hole and increases with the distance being away the film hole;the irrigation minima has distinct effect on soil water distribution and the soil content in the soil profile increases with irrigation minima;Water consumption amount increase with irrigation minima.The distinct power function exits between water consumption amount and irrigation minima.The result provided the proof for reasonable fertilizer and evaluating effect of nitrogen on environment.