微咸水矿化度对重度盐碱土壤入渗特征的影响

摘要

通过微咸水室内一维垂直入渗试验,分析了淡水以及4种不同矿化度(2,3,4,5 g·L-1)微咸水对重度盐碱土壤累积入渗量、湿润锋运移深度、土壤含水率、入渗历时、入渗速率的影响.结果表明:累积入渗量、湿润锋运移深度、土壤含水率随微咸水矿化度的增加呈现增大的趋势,但与淡水相比,2,3,4,5 g·L-1微咸水的累积入渗量、湿润锋运移深度随入渗时间的变化差异较小;同一土层,土壤含水率大小比较:淡水<5g·L-1<3g·L-1<2g·L-1<4 g·L-1;在微咸水灌溉条件下,累积入渗量与湿润锋运移深度呈线性关系.采用Kostiakov模型,Philip模型和Green-Ampt模型模拟微咸水入渗过程,结果显示,Kostiakov模型可以更好地描述重度盐碱土入渗率与入渗时间的关系.%One-dimension vertical water infiltration experiments were conducted using a vertical soil column.The study was conducted to study the relations between cumulative infiltration,wetting front depth,soil moisture content,in-filtration rate and infiltration time under different mineralization degree of infiltration water.The results showed that cu-mulative infiltration,wetting front depth,soil moisture content increased with the mineralization degree of infiltration wa-ter.However,compared with fresh water,the changes of wetting front depth and cumulative infiltration of 2,3,4 g·L-1 and 5 g·L-1is smaller.In the same depth of soil,soil moisture content was characterized by fresh water <5 g·L-1<3 g·L-1<2 g·L-1<4 g·L-1.Cumulative infiltration was in good linear relationship with wetting front depth under brackish water irrigation.The Kostiakov infiltration model,Philip infiltration model and Green-Ampt infiltration model was compared in terms of quantifying saline water infiltration process,by which Kostiakov model was proposed.