单点源肥液入渗尿素的运移转化特性研究

Transport and Transform Characteristics under Single Film Hole Fertilizer Solution Infiltration of Soil Urea

通过室内入渗试验,研究了单膜孔入渗条件下尿素的运移与转化特性。结果表明:溶质运移的对流机理是尿素分子运移的主要机制。土壤胶体对尿素分子的吸附作用表现为尿素在膜孔中心附近范围内的含量较高。施肥5d后土壤铵态氮达到最高峰,随后的10d内迅速下降至土壤的本底值;而土壤硝态氮一直平稳升高,于施肥后15d达到高峰值。该成果为进行膜孔灌施肥技术研究奠定了理论基础。

Based on lab experiment,transport and transform characteristics of urea under film hole single point infiltration were researched.The results showed that the convection of solute transport was the main mechanism of the urea molecule transport.The sorption of soil colloid reflected that the urea content was much higher at the scope of film hole center.The NH＋4 was the maximum in 5 days after fertilization and then decreased to the background value rapidly in the succedent 10 days.While the NO-13 content increased steadily with the maximum value in 15 days after fertilization.The results lay a foundation for study of film hole irrigation fertilizer technique.