【摘要】 试验研究了不同供水水头(H=0,-0.5,-1.0,-1.5m)和钠吸附比SAR为30时不同盐分浓度(C=80,20,2mmol/L)对负压灌溉土壤水分运移的影响,并以清水灌溉为对照处理。试验结果表明:各处理的湿润锋开始时运移较快,等时间线较稀疏,随着灌溉时间增加,运移变慢,等时间线变密。湿润体都近似为椭球体。累计入渗量,最大水平和最大垂直湿润距离都随时间的增加而增大,入渗率随时间的增加而减小。H=0m时清水的湿润锋运移,累积入渗量,最大水平和最大垂直湿润距离及宽深比均大于咸水。H=0,-0.5m时浓度对累积入渗量,最大水平和最大垂直湿润距离及宽深比的影响较大;H=-1.0,-1.5m时的影响减小;H=-1.0m时基本没有影响。更多还原

【Abstract】 The experiments study the influence of different water supply head(H=0.5,0,-0.5,-1.0 m)in three salt concentration levels(C=80,20,2 mmol/L)when the sodium adsorption ratio is 30 mg/L.The results show that under different treatments the wetting front advances quickly at first,but will be slowed down as time goes on.The shapes of wetting front are all nearly ellipsoid.The cumulative infiltration rate,maximum horizontal and vertical wetted distance increases with the increase in time,while the infiltration rate decreases with the increase in time.The cumulative infiltration,maximum horizontal vertical wetted distance and breadth depth ratio of control treatment are larger than those under treatments used saline water.The influence of salt concentration on cumulative infiltration,maximum horizontal vertical wetted distance and breadth depth ratio are prominent when H=0,-0.5 m.While salt concentration has minor effect on cumulative infiltration,maximum horizontal vertical wetted distance and breadth depth ratio when H=1.0 and 1.5 m.Salt concentration has no influence when H=-1.0 m.更多还原