Based on the field experiments for different fertilizing methods and inflow rates in the greening period of winter wheat, the spatial and temporal distribution of Nitrogen in soil and surface water were analyzed, and the factors affecting the distribution uniformity of Nitrogen in soil after irrigation were discussed. The results showed that the influence of inflow rate on the distribution of Nitrogen were not obvious, however the fertilizing methods had obvious effects on it. Under fertigation the spatial and temporal distribution difference of Nitrogen in surface water were not obvious, but it was very obvious for scattering fertilizer. The spatial distribution uniformity of Nitrogen in soil after irrigation can be well improved under fertigation, the coefficient of variation Cv was about 0.07 at lm soil depth, which was far smaller than that under scattering fertilizer. Under fertigation the distribution uniformity of Nitrogen had strong relation with the distribution of irrigation water, however under scattering fertilizer it was mainly related with the distribution of Nitrogen in surface water and the distribution of irrigation water. Fertigation was better than the scattering fertilizer in improving the distribution uniformity of Nitrogen and decreasing the loss of fertilizer during the irrigation, and it was easier for the joint management of water and fertilizer.%分析不同灌溉施肥方式下氮素时空分布特征可为改进畦灌施肥技术与方法提供科学依据.该研究基于冬小麦返青灌溉开展的不同入畦流量下撒施和液施硫酸铵时获得的畦灌试验观测结果,分析2种不同施肥方式下地表水流和土壤中氮素时空分布规律,讨论不同施肥方式下影响灌后土壤氮素空间分布均匀性的要素.结果表明,施肥方式对地表水流和土壤中氮素分布影响显著,入畦流量对其影响不显著.液施下地表水流中氮素时空分布差异不显著,撒施下具有明显时空变异性；液施能明显改善灌后土壤氮素空间分布均匀性,灌后1d1m土层内氮素空间变异系数为0.07,明显小于撒施.土壤氮素增量分布均匀性在液施下主要与灌水量分布有关,撒施下则与地表水流中氮素分布和灌水量分布有关.液施在提高施肥均匀性和减小灌溉期间肥的损失方面优于撒施,且更易于水肥联合管理.
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