层状土膜孔灌肥液自由入渗氮素运移转化模拟研究  

Simulation Study on Migration and Transformation of Nitrogen in Layered Soil under Film-hole Irrigation

作　　者：陈琳 艾南竹 费良军[3] 于敦福 王亮 CHEN Lin;AI Nanzhu;FEI Liangjun;YU Dunfu;WANG Liang(Qingdao Yinhuang Jiqing Water Group Co.,Ltd.,Qingdao Shandong 266000,China;School of Environmental and Municipal Engineering,Qingdao University of Technology,Qingdao Shandong 266555,China;School of Water Resources and Hydropower,Xi'an University of Technology,Xi'an Shaanxi 710048,China)

机构地区：[1]青岛引黄济青水务集团有限公司,山东青岛266000 [2]青岛理工大学环境与市政工程学院,山东青岛266555 [3]西安理工大学水利水电学院,陕西西安710048

出　　处：《农业工程》2022年第10期72-80,共9页AGRICULTURAL ENGINEERING

摘　　要：采用试验与数值模拟相结合的方法,探究了层状土条件下膜孔灌肥液自由入渗氮素运移转化规律。试验设置了3种夹砂层位置,利用HYDRUS-3D模型对层状土膜孔灌肥液自由入渗水氮运移和氮素转化过程进行模拟预测,并进行了验证。研究表明:根据简化膜孔灌入渗量的计算方法,将膜孔灌分为垂直一维入渗和膜孔侧渗,膜孔侧渗量在膜孔入渗量中起主导作用,并且受夹砂层位置的影响较大,随夹砂层埋深的增加而增大,而夹砂层位置对垂直一维入渗减渗作用较小;层状土膜孔灌湿润体的湿润锋面形状与均质土的半球体或半椭圆体有明显不同,并且在土-砂交界处有明显的不连续现象;随再分布时间的延长,土壤湿润体中尿素含量整体呈降低趋势;再分布阶段,膜孔中心处附近铵态氮均大于湿润锋处的,并随着远离膜孔中心方向逐渐减小,铵态氮主要集中分布在夹砂层以上土层中,并且在土-砂界面含量明显增加;随着时间的增加,相同位置处的硝态氮含量增大,水平湿润锋处的硝态氮含量较膜孔中心附近的增加速度快,并在土-砂界面含量较大;尿素转化运移过程中氮素的实测值与模拟值一致性较好,说明氮素链式反应参数选取较合理,模型模拟效果较好。该研究为模拟预测层状土条件下膜孔灌肥液自由入渗氮素运移和转化规律提供了理论和方法基础。Layered soil is a common soil structure in nature, and film-hole irrigation is a new type of water-saving irrigation technology. Method of combining experiment and numerical simulation was used to explore migration and transformation law of nitrogen in free infiltration of fertilizing liquid under film-hole of layered soil. Three kinds of sand inter-layer positions were set up in experiment,and the HYDRUS-3D model was used to simulate and predict nitrogen transport and transformation process of layered soil under film-hole irrigation and fertilizer solution,and verified. According to simplified calculation method of film-hole infiltration,filmhole infiltration was divided into vertical one-dimensional infiltration and film-hole lateral infiltration. Influence of position of sand interlayer was greater,and it increased with increase of burial depth of sand inter-layer,while position of sand inter-layer had little effect on vertical one-dimensional infiltration and infiltration reduction. Shape of wetting front of layered soil infiltration was significantly different from hemisphere or semi-ellipsoid of homogeneous soil, and there was obvious discontinuity at soil-sand interface. With increase of redistribution days,urea content in soil wet body showed a decreasing trend as a whole. In redistribution stage,ammonium nitrogen near center of membrane hole was larger than that at wetting front, and gradually decreased with distance from center of membrane hole. Ammonium nitrogen was mainly distributed in soil layer above sand layer,and in soil-sand interface content increased significantly. With time increased, nitrate nitrogen content at the same position increased. Nitrate nitrogen content at horizontal wetting front increased faster than that near center of film hole, and content was larger at soil-sand interface. In process of urea conversion and migration,measured value of urea nitrogen content was in good agreement with simulated value,indicating that selection of nitrogen chain reaction parameters was more reaso

关 键 词：层状土 膜孔灌 HYDRUS-3D模型 硝态氮 铵态氮 自由入渗 

分 类 号：S275[农业科学—农业水土工程]