滴灌施肥条件下土壤湿润锋变化规律研究  

A Study on Soil Moisture Change under Drip Irrigation

作　　者：赵彦波 尹娟[1,2,3] 尹亮 ZHAO Yan-bo;YIN Juan;YIN Liang(School of Civil Engineering and Water Conservancy, Ningxia University, ~inchuan 750021, China;Engineering Research Center for Efficient Utilization of Water Resources in Modern Agriculture in Arid Regions, Yinehuan 750021, China;Ningxia Research Center of Technology on Water-saving Irrigation and Water Resources Regulation, Yinchuan 720021, China)

机构地区：[1]宁夏大学土木与水利工程学院,银川750021 [2]旱区现代农业水资源高效利用教育部工程中心,银川750021 [3]宁夏节水灌溉与水资源调控工程技术研究中心,银川750021

出　　处：《节水灌溉》2018年第5期5-10,共6页Water Saving Irrigation

基　　金：宁夏水利厅科技教育处项目(20140709);宁夏大学一流学科项目(NXYLXK2017A03)

摘　　要：针对宁夏旱区枸杞滴灌施肥系统设计、水肥管理方案等不完善问题,研究了滴灌施肥条件下湿润锋的运移变化规律,为大田滴灌施肥系统设计提供参考依据。通过室内土箱实验模拟大田点源滴灌,试验以滴头流量和施氮浓度为变量,以计划湿润层为控制量,采用完全随机组合设计,研究湿润锋变化规律。灌水氮素浓度一定的条件下,滴头流量越大灌水到达计划湿润层的时间就越短,形成的湿润体体积越大,灌水结束后湿润体水分再分布的距离越大;滴头流量一定的条件下,灌水氮素浓度越大越有利于水分在竖直方向的迁移扩散,水分到达计划湿润层的时间越短,形成的湿润体体积相对较小,灌水结束后土壤水分再分布的距离越小;水平湿润锋和垂直湿润锋运移距离与时间之间满足幂函数关系,幂指数b随流量q和施肥浓度c无明显变化,幂函数系数a随滴头流量的增大而变大,随施肥浓度的增大而变小。滴头流量和施肥浓度都会影响水分在土壤中的运移分布状况,滴头流量起主要作用。水分运移距离与时间满足幂函数关系,可以通过函数关系式来预测土壤水分运移深度。Aiming at the problems of imperfect fertilization system design and water fertilization management scheme for Chinese wolfberry in arid areas of Ningxia,the wetting front migration regulation under drip irrigation is studied to provide reference base for the field fertigation system design. The indoors soil box experiment is conducted to simulate the field point-source drip irrigation. In the experiment,the emitter flow and nitrogen concentration is taken as variable,the planned moisture layer is taken as controlled variable,and the completely random combination design is adopted. The results show that： under the same nitrogen concentration,the larger the drop flow,the shorter the time for the water to reach the wet layer,the larger the volume of the wetting body,and the greater the distance that the wetting front will continue to move after the irrigation; under the same drip flow,the larger the fertilizer concentration,the better the water migration in the vertical direction,the shorter the time for the water to reach the planned moisture layer,the smaller the wetting body,and the smaller the distance the water distribution after the irrigation; there exists a power function relationship between migration distance and time of horizontal wetting front and vertical wetting front,there is no significant change for power exponent b with the change of flow q and fertilizer concentration c,and the coefficient a increases with the increase of drop head flow,and decreases with the increase of fertilizer concentration; both drip flow and fertilizer concentration can affect the soil moisture distribution,but the drip flow plays a major role. The soil moisture migration depth can be predicted through function relation formula.

关 键 词：土壤水分运移 滴灌 滴头流量 氮素浓度 单点源 

分 类 号：S275.6[农业科学—农业水土工程]