水中带沙是浑水灌溉较清水灌溉的本质区别，为揭示浑水含沙率对一维垂直入渗特性及致密层形成特性的影响，通过室内一维垂直入渗试验，以清水入渗为对照，设置了4个浑水含沙率水平（3%、6%、9%、12%），研究了浑水含沙率对一维垂直入渗能力、湿润锋运移距离、致密层土壤颗粒组成及落淤层厚度等的影响，分别提出了以浑水含沙率和入渗历时为自变量的累积入渗量模型和湿润锋运移距离模型，建立了不同含沙率的浑水一维垂直入渗落淤层厚度与入渗历时之间的关系。结果表明：浑水累积入渗量、入渗率和湿润锋运移距离均随含沙率的增加而减小，而落淤层厚度随浑水含沙率的增加而增大；入渗初期（0~20 min）的落淤层厚度较小，入渗中期（20~130 min）的落淤层厚度增加较快，而其厚度增加速率逐渐变小，入渗后期的落淤层厚度稳定增加；随着浑水含沙率的增大，滞留现象越明显，落淤层细颗粒相对含量越少，粗颗粒相对含量越多；滞留层细颗粒相对含量随着含沙率的增加而增多，其物理性黏粒含量显著高于原土壤，特别是在入渗深度为0~1 cm处。

Sediment in water is the essential difference between the irrigation of muddy and clean water. The one-dimensional vertical infiltration experiment with muddy and clean water was conducted to reveal the influence of sediment concentration in muddy water on one-dimensional vertical infiltration characteristics and dense layer formation. Four sediment concentrations (3%, 6%, 9%, 12%) were set up to study the effects of sediment concentration on one-dimensional vertical infiltration capacity, wetting front movement distance, soil particle composition in dense layer and the thickness of deposition layer. The models of cumulative infiltration and the wet front movement distance with sediment concentration in muddy water and infiltration duration as independent variables were proposed respectively, and the relationship between the thickness of deposition layer and the infiltration duration of one-dimensional vertical infiltration of muddy water with different sediment concentrations were established. The results showed that the increase of sediment concentration in muddy water, the cumulative infiltration, the infiltration rate and the movement distance of wetting front of muddy water all decreased, while the thickness of deposition layer increased. The thickness of the deposition layer was small at the initial stage of infiltration (0-20 min), increased rapidly in the middle stage of infiltration (20-130 min) but the increasing rate gradually decreased, and increased steadily in the late infiltration stage. With the increases of sediment concentration in muddy water, the sediment retention became more obvious, so the fine particles decreased while the coarse particles increased in the deposition layer. The fine particles increased in the stranded layer with the increase of sediment concentration, and the physical clay particles was significantly higher than that of the original soil, especially at 0-1 cm infiltration depth.

S275.3

国家自然科学基金项目（52079105、52000120））和湖北省水利重点科研项目（HBSLKY201919））资助。