摘要
为揭示土壤初始含水率对浑水膜孔灌单点源自由入渗的影响,通过开展不同初始含水率的室内浑水膜孔灌试验,研究了土壤初始含水率对浑水膜孔灌自由入渗特性、减渗特性以及土壤含水率分布的影响,并建立了基于土壤初始含水率和累积入渗时间的浑水膜孔灌自由入渗模型和减渗模型。研究表明:当浑水的含沙率和膜孔的直径一定时,随土壤初始含水率的增大,相同时间内的单位膜孔面积累积入渗量呈逐渐减小的趋势,初始含水率为4.96%,7.43%,10.07%和12.40%的分别较风干条件下的减少了19%,33%,45%和56%,减渗效果明显。通过对含水率分布特征研究发现,在靠近和远离膜孔的部位含水率变化梯度较大,平均含水率梯度达到了2%/cm,而中间部位含水率变化较小,平均含水率变化梯度仅为0.65%/cm。
In order to reveal the effects of initial soil moisture content on the soil water infiltration property under single point of freedom muddy water film hole irrigation,the test was carried out under different initial soil moisture content.The test studied on the influence of initial soil moisture content on the infiltration characteristics,reduced infiltration characteristics and distribution of soil moisture content of single point of freedom muddy water film hole irrigation,and built film hole irrigation free irrigation model with cumulative time and permeability reducing model.The test results indicated that the infiltration capacity of per unit film hole area had decreasing trend in the same time as the increasing of the initial moisture content of the soil and the initial moisture content of 4.96%,7.43%,10.07% and 12.40% decreased by 19%,33%,45% and56%,respectively compared with the dry conditions test.While the permeability reducing affection had increasing trend under the fixed sand percentage of muddy water and the film hole diameter.Near and far away the film hole,the gradient of water content changed in a large and it＇s about 2%/cm.Less change of the gradient of water content was in the middle part and it＇s about 0.65%/cm.
出处
《水土保持学报》
CSCD
北大核心
2016年第5期235-239,254,共6页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(51479161
51279157)
国家农业公益项目(201203003-1)
关键词
初始含水率
浑水膜孔灌
入渗量
减渗量
initial soil content
muddy water film hole irrigation
infiltration amount
reducing quantity
