施肥条件下浑水膜孔灌土壤氮素运移转化及水肥耦合特性研究

This project intends to combine the irrigation districts of the Yellow River basin in our country with the characteristics of muddy water sediment film hole irrigation and fertilization. The technical routes of this study is based on experimental and combines numerical simulation with the theoretical research. The muddy water film hole irrigation infiltration and irrigation test under the condition of fertilization indoor and outdoor are carried out. This research studys muddy water film hole free irrigation of single film hole from a point source and Hole point source multi film interference infiltration of soil nitrogen transport and transformation characteristics and coupling law of fertilizer and fertilization methods, the amount of fertilizer application, the type of fertilizer and the characteristics of muddy cement sand. The relationship between the infiltration volume of muddy water film hole irrigation and nitrogen distribution of wetting soil under the condition of fertilization are revealed. The soil nitrogen transportation and transformation model under muddy water film hole irrigation and fertilization are established. The muddy water film hole irrigation water-saving and fertilizer-conserving mechanism under the condition of fertilization are discussed. The nitrogen distribution characteristics of along the long direction in border (furrow) and the profile under muddy water film hole irrigation and fertilization are studied. The water and fertilizer to forecast irrigation quality and find out the best optimization combination of technology elements under muddy water film hole irrigation and fertilization are comprehensively studied. The relationship between synergistic effects of water and fertilizer for crops growth and yield and improve the efficiency of nitrogen utilization under muddy water film hole irrigation and fertilization are studied. The research has important scientific value and practical significance in production for further study of muddy water film hole irrigation under the condition of fertilization.

本项目拟结合我国黄河流域灌区以多泥沙浑水膜孔灌溉和农田施肥的特点，采用试验、数值模拟和理论研究相结合、以试验为主的技术路线，在室内外开展施肥条件下的浑水膜孔灌入渗和灌水试验，研究浑水膜孔灌施肥单膜孔点源自由入渗和多膜孔点源交汇入渗土壤氮素运移转化特性和水肥耦合规律及其施肥方式、施肥量和施肥种类及浑水泥沙的影响特征，揭示施肥条件下浑水膜孔点源入渗量与湿润体土壤氮素分布之间的关系，建立浑水膜孔施肥入渗土壤氮素运移转化模型；探讨浑水膜孔灌施肥农田的节水保肥机理，研究施肥条件下浑水膜孔灌水肥耦合规律及其影响因素，以及研究施肥条件下浑水膜孔灌灌水技术要素的优化组合。以上研究为进一步研究施肥浑水膜孔灌技术奠定科学基础，具有十分重要的科学价值和生产实际意义。

项目针对我国黄河流域灌区以多泥沙河流浑水膜孔灌和农田施肥的特点，采用试验、理论研究和数值模拟相结合的技术路线，在室内外开展了施肥条件下浑水膜孔灌入渗和灌水试验，研究了施肥条件下浑水膜孔灌土壤水氮运移转化和耦合特性及其影响因素，揭示了施肥量、肥液浓度、浑水含沙率、泥沙颗粒级配等因素对施肥条件下浑水膜孔灌单膜孔自由入渗和多膜孔点源交汇入渗土壤水氮运移特性及其耦合规律的影响特征，建立了浑水膜孔灌自由入渗和交汇入渗水氮运移特征与各影响因素之间的关系；研究了不同肥液浓度和浑水泥沙特性的膜孔灌自由入渗和交汇入渗湿润锋运移和水氮分布特性与入渗时间之间的关系，建立了包含各影响因素的湿润锋运移模型，提出了自由面和交汇面及湿润锋内的土壤水氮运移转化和分布模型；揭示了浑水膜孔灌入渗的湿润体土壤水分和氮素分布规律；通过试验和数值模拟，研究了夹砂层对层状土膜孔灌肥液自由入渗土壤水氮运移转化及耦合特性的影响规律；研究了混施γ-聚谷氨酸浑水膜孔灌自由入渗表层致密层的形成特性，建立了施加γ-聚谷氨酸膜孔灌入渗量和土壤含水率分布的关系模型；利用HYDRUS-1D建立了穴播膜孔灌冬小麦土壤水氮运移转化的模拟模型，揭示了膜孔灌条件下冬小麦土壤水氮运移转化和水肥利用特性；研究了浑水膜孔灌土壤湿润锋运移距离、累积入渗量、土壤水氮含量及分布的时空变化规律，建立了浑水膜孔灌三维Green-Ampt入渗模型；建立了膜孔灌自由入渗多因素影响的累积入渗量数学模型，揭示了浑水膜孔点源肥液入渗量与湿润体土壤水氮分布之间的关系，阐明了浑水膜孔灌的节水保肥机制，研究了浑水膜孔灌技术要素及其最佳组合。研究成果为进一步研究浑水膜孔灌施肥灌溉技术奠定了科学基础，具有十分重要的科学价值和生产实际意义。项目研究成果已公开发表学术论文22篇，其中SCI收录论文7篇、EI收录论文3篇；结合该项目研究，培养博士后2名、博士研究生4名和硕士研究生8名。