微咸水滴灌下湿润锋运移特征研究

Research on the Transport Characteristics of Soil Wetting Front under Drip Irrigation with Saline Water

滴灌被认为是最适合用于微咸水开发利用的节水灌溉技术,其湿润体的范围及动态变化影响着作物的生长及产量。由于田间滴灌湿润体地下部分不容易被观测到,则土表面湿润距离是最直观的表明灌水湿润程度的标志,本文以田间试验为基础,研究了不同水质、滴头流量、灌水量下滴灌点源及交汇区地表湿润锋运移过程。研究结果表明,湿润锋交汇前,随着滴水水质及滴头流量的增大水平湿润距离增加,滴头流量越大水平湿润距离增加的幅度越大;随灌水量的增加,试验结束时水平湿润距离也增大。湿润锋交汇后,随滴水水质及滴头流量的增大,交汇时间提前;交汇区宽度及地表湿润比均随滴水水质、滴头流量及灌水量增加均增加;通过比较不同滴水水质交汇区与相同湿润位置单点源下水盐含量,表明交汇区含水量大于相同湿润位置处单点源下的含水量,滴水水质大于3.03 g/L交汇区含盐量明显高于相同湿润位置处单点源下的含盐量。该研究结果对了解微咸水滴灌因素对土壤水分运移的影响具有一定的指导作用。

Drip irrigation is known optimum savings water irrigation technology with saline water,the extension and changer of soil wetting front effect crop growth and yield.But underground of soil wetting is no observed,the horizontal advance of wetting front is best intuitionistic symbol of irrigation grade,this text is base on the field test,observing the process of soil wetting front in the different water quality,dripper discharge,drop water.The results indicated,before Iterference Infiltration the horizontal advance of wetting front increased with water quality increasing;the horizontal advance of wetting front increased with dripper discharge and drop water increasing,when dripper discharge was bigger,the scope of the horizontal advance of wetting front increased;after iterference infiltration,iterference infiltration time was advanced with water quality and dripper discharge increased,iterference width and the earth＇s surface wetting proportion was increasing with water quality,dripper discharge and drop water.Through comparisons the soil water and salt content in the same wetness station,results that soil water content was bigger in the iterference infiltration section than single infiltration section,when water quality exceeded 3.03 g/L the soil salt content was obvious bigger in the iterference infiltration.The result of study has certain guidance functions to know the infection of soil water transport under drip irrigation with saline water factor.