表层掺黏土对砂壤土水分入渗的影响

Effects of Clay Mixed on Soil Water Infiltration in Surface of Sandy Loam

[目的]针对我国北方砂壤土水分利用效率低的特点,通过室内模拟试验研究了砂壤土表层添加不同黏粒量对砂壤土湿润锋进程、累计入渗量、土壤剖面含水率的影响,分析了土壤中黏粒添加量对砂壤土水分运动影响和机制,旨在为砂壤土工程改良提供理论依据和实践指导。[方法]通过室内土柱模拟试验,设置常规对照(CK)以及2%、5%、10%和20%4个掺黏量,定水头条件下研究不同掺黏量对砂壤土水分入渗特征的影响。[结果]砂壤土表层掺黏后,显著减小了湿润锋进程。随着土壤表层掺黏量的增加,湿润锋下移速率、入渗速率逐渐减慢,累计入渗量减少。湿润锋、累计入渗量与时间之间符合幂函数关系。[结论]在入渗过程中,土壤表层掺黏能显著增加土壤对外界水分的蓄积量,提高土壤的储水量。

[Objective] In view of the low efficiency of water use in northern sandy loam soil,through laboratory experiment,the effects of loam surface adding different amount of sticky situations on sandy loam soil wetting front process,cumulative infiltration,moisture content of the soil profile were integrated,and soil clay content on the sandy loam soil water movement effects and mechanisms were analyzed.The research aimed to provide a theoretical basis for improving sandy loam engineering and practical guidance.[Method] A laboratory soil cylinder simulation experiment was carried out to investigate the impacts of clay mixed sandy loam on soil infiltration and soil moisture.[Result] The sandy loam mixed with sticky surface significantly reduced the wetting process.With the increase of the amount of topsoil mixed with sticky,moist peaks down rate,infiltration rate,cumulative infiltration gradually slowed down.Wetting front,between cumulative infiltration and time met power function.[Conclusion] Infiltration process,sticky soil surface doping could significantly increase soil moisture accumulation on the outside,and improve soil water storage.