摘要
通过室内模拟试验,在土槽中埋设TDR100时域反射仪传感器自动检测土壤含水率、埋设负压计陶土头测定基质势,分析土壤水分运移特征,研究双点源滴灌条件下土壤水分运移规律.结果表明,滴灌点源水分渗入土壤之后,随着距滴头距离的增加,入渗湿润体内的土壤含水率降低,湿润锋交汇界附近的土壤含水率一般均不小于相同土壤深度的含水率;5 ～ 35cm土壤含水率迅速增大到0.315 cm^3/cm^3左右.供水停止后,上层的水分逐渐递减,而下层土壤的水分逐渐增加,且随着时间的延长,水分变化的速率越来越慢.因此,适当灌水量条件下滴灌交汇不会产生深层渗漏,且使用滴灌时作物根系层蓄水保墒效果良好.研究结果可为滴灌方式的适用性、植物选栽提供参考.
Surface drip irrigation is the most advanced method of irrigation to date,which enables the application of appropriate amounts of water to the soil through drippers.Study of soil water movement under infiltration of point source drip irrigation plays an important role in the promotion of drip irrigation technology.An indoor soil bin was designed in this study.Time domain reflectometry （TDR100） probes and tensiometers were adopted to measure soil water contents and soil water potential,respectively.The infiltration rates and wetting front interference under double point source drip irrigation emitters were analyzed.With the distance apart from drip increasing,the soil moisture of wetted volume from drip irrigation was reduced,and the soil moisture of wetted front on the intersection side was not smaller than the soil moisture of similar wetted depth.The soil water content （SWC） of 5-35 cm layer reached O.315 cm^3/cm^3 rapidly during the irrigation phase.The soil moisture of the top layer gradually decreased,the soil moisture of sublayers gradually increased,and the rate of change of soil moisture slowed down in the redistribution phase.Our study would help in designing surface drip systems for efficient water use with minimum drainage.
出处
《中国水土保持科学》
CSCD
2014年第4期67-72,共6页
Science of Soil and Water Conservation
基金
国家自然科学基金"毛乌素沙地灌溉植被耗水机理及其对地下水资源的影响"(41172225)
高校基本科研业务费项目(2652012068)
关键词
滴灌
土壤水分
交汇
湿润锋
drip irrigation
soil moisture
interference
wetting front
