通过室内入渗试验,研究了不同施肥方式对膜孔点源入渗尿素转化特性的影响.结果表明,不同施肥方式下尿素的转化规律基本一致,施肥5d后土壤铵态氮达到最高峰,随后的10 d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15 d左右达到最大值.不同施肥方式下膜孔点源入渗土壤尿素转化后铵态氮和硝态氮的分布特征有明显的不同.灌施情况下土壤铵态氮含量和硝态氮含量沿着远离膜孔中心的方向逐渐减小；表施情况下土壤铵态氮和硝态氮含量集中分布在土壤表层以下7～15 cm的土层内；深施情况下土壤铵态氮和硝态氮含量集中分布在土壤表层5～ 17 cm的土层内.%Based on lab experiment, the influence of fertilization application on transform characteristics of soil urea under film hole single point infiltration was researched. The results show that the transform laws of urea under different fertilization modes are the same. The NR4+ - N content comes to the maximum value in 5 days after fertilization and de-creases to the background value rapidly in the succedent 10 days. While the NO3- - N content increases all along and comes to the maximum value in 15 days after fertilization. The distribution characteristics NH4+ - N and NO3- - N after transform of soil urea are different. The soil NH4+ - N content and NO3- - N content under irrigation with fertilizer de-crease with the distance further from the film hole center. The distribution of soil NH4+ - N content and NO3- - N content under surface application concentrate in the 7 ~ 15 cm scope below soil surface. The distribution of soil NH4+ - N content and NO3- - N content under deep application concentrate in the 5 ~ 17 cm scope below soil surface. The results lay a foundation for study of film hole irrigation fertilizer technique.
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