【摘要】 为分析透气隔水(弱透水)埋体促进水分入渗与溶质运移功效,开展了不同容重(1.40,1.45,1.50,1.60 g/cm~3)透气隔水(弱透水)埋体的一维垂直土柱入渗试验,分析了不同容重的透气隔水(弱透水)埋体对土壤水分入渗与溶质分布的影响。结果表明,透气隔水(弱透水)埋体能够增加土壤累积入渗量,推动湿润锋运移,在一定范围内,随着透气隔水(弱透水)埋体容重增加,湿润锋推进速度与土壤入渗率均增加。600 min时,土壤累积入渗量相对增加7.42%～29.17%,湿润锋深度达到27 cm,入渗时间相对减少26.97%～64.27%。相比于对照组,不同容重的透气隔水(弱透水)埋体均能降低溶质向深层土壤迁移数量。Philip模型和代数模型均能描述透气隔水(弱透水)埋体土壤水分入渗过程,且Philip模型中吸渗率S和代数模型中综合形状系数α均与透气隔水(弱透水)埋体内外容重比呈正相关关系。研究结果表明透气隔水(弱透水)埋体能够通过改变上层土壤吸力分布提高水分入渗能力与溶质传输效率,实现对城市雨水径流调控和净化。更多还原

【Abstract】 In order to analyze the effect of air-permeable and water-proof soil on water infiltration and solute transport, an one-dimensional vertical soil column infiltration test was carried out with different bulk densities(1.40, 1.45, 1.50, 1.60 g/cm~3). The results showed that the air-permeable and water-proof(weak permeable) buried body could increase the cumulative infiltration of soil and promote the migration of wetting front. In a certain range, with the increases of the bulk densities of the air-permeable and water-proof(weak permeable) buried body, both the infiltration rate and the migration rate of wetting front increased. When the infiltration time was 600 min, the cumulative infiltration of soil increased by 7.42%～29.17%, and the depth of wetting front reached 27 cm. The infiltration time decreased by 26.97%～64.27% correspondingly. Compared with the control group, the amount of solute migration to the deep soil was reduced by different bulk densities of the air-permeable and water-proof(weak permeable) buried body. Both Philip model and algebraic model could describe the infiltration process of soil water in the air-permeable and water-proof(weak permeable) buried body, and the permeability s in Philip model and the comprehensive shape coefficient α in the algebraic model were positively correlated with the volume weight ratio and the volume weight ratio inside and outside the air-permeable and water-proof(weak permeable) buried body. The results showed that the air-permeable and water-proof(weak permeable) buried body could improve the water infiltration capacity and solute transport by changing the suction distribution of the upper soil, and realize the regulation and purification of urban rainwater runoff.更多还原