中文摘要：

为了揭示不同湿润速度对土壤饱和导水率（Ks）的影响机理,针对2种类型土壤（粘壤土和砂壤土）,设置8个湿润速度（2.25 mm/h,4.25 mm/h,6.25 mm/h,8.25 mm/h,10.25 mm/h,12.25 mm/h,14.25 mm/h和16.25 mm/h）,以无湿润速度（0mm/h）的环刀浸泡饱和为对照（CK）,共9个处理,进行室内Ks的测定,最后通过分析团聚体指标和试验后土体微观结构照片验证结论.结果表明：湿润速度显著影响Ks,湿润速度越大,Ks越小.2种土壤Ks与湿润速度呈线性负相关,相关系数R2均达到0.96以上.湿润速度从0 mm/h增加到16.25 mm/h,粘壤土Ks由2.94 cm/h变化至2.01 cm/h,降低31.50％,而砂壤土则在3.97～2.86cm/h之间变化,降低27.79％.粘壤土的Ks受湿润速度影响非常明显,而砂壤土的Ks只有在高速湿润下才表现出显著差异.对于不同类型土壤,同一湿润速度下Ks也不相同,且差异显著,这与2种土壤的团聚体指标密切相关.湿润速度对Ks影响机理主要是土体中水流运动产生的剪切力破坏了土壤结构,湿润速度越大,产生的剪切力也越大,土壤结构破坏越完全,从而导致土壤导水能力显著下降.

英文摘要：

In order to reveal the influence of wetting rate on soil saturated hydraulic conductivity（Ks）, this laboratory experiment selected 2 types of soils（clay loam and sandy loam soil） and established 9 wetting rate treatments including 8 wetting rates（2. 25 mm/h, 4. 25 mm/h, 6. 25 mm/h, 8. 25 mm/h, 10. 25 mm/h, 12. 25 mm/h, 14.25 mm/h and 16.25 mm/h） and control treatment（0 mm/h）. In control treatment, soil in foil sampler was soaked to saturation. Ks was measured in all treatments, and aggregate index and photographs of soil microstructure were analyzed to verify the conclusions. The results showed that Ks was significantly affected by wetting rate, which decreased with the increasing wetting rate. Ks of both 2 types of soils showed significant negative correlation with wetting rate and the correlation coefficient R2 were above 0.96. When wetting rate increased from 0 mm/h to 16.25 mm/h, K, of clay loam soil decreased by 31.50%, ranging from 2.94 cm/h to 2.01 cm/h, and K, of sandy loam soil decreased by 27. 79%, ranging from 3. 97 cm/h to 2.86 cm/h. Wetting rate had significant influence on Ks of clay loam soil, while Ks of sand loam soil differed among wetting rate treatments only when wetting rates were high. In the same wetting rate treatment, Ks significantly differed between 2 types of soils, which were closely related with aggregate index. The influence mechanism of wetting speed on Ks was that the shear force of soil water movement destroyed soil structure, with higher wetting rate leading to greater shear force and more serious destroy on soil structure, which caused obvious reduction of soil hydraulic conductivity.