【摘要】 分析了不同施肥时期对砂质潮土小麦产量、氮素吸收与利用、土壤残留与氮素损失的影响。结果表明 ,氮肥在一半做底肥的基础上 ,以拔节期追肥小麦产量最高。在返青期与孕穗期追肥之间 ,低氮肥用量情况下 ,以孕穗期追施小麦产量较高 ,而在高氮肥用量时二者没有差异。氮肥一半做追肥施用植株吸收氮量比氮肥全部做底肥显著提高 ,这种提高主要来自肥料氮。拔节期追肥利用率最高。小麦收获后土壤中肥料残留氮的 31 7%～ 66 8%分布在 0～ 40cm土层内 ,且随施肥时间的推迟 ,0～ 40cm土层内残留氮所占的比例增加 ,而底施和返青期追施的氮肥在下层残留的比例高于后期追肥 ,其在 80～ 1 0 0cm土层的累积量甚至超过了表层土壤残留量。但后期追肥氮素挥发损失严重。更多还原

【Abstract】 The effects of different fertilization stage on wheat yield,nitrogen uptake,utilization,residue,distribution and nitrogen balance were studied by potted plant experiment.The results showed that the highest yield obtained appeared in the treatment of topdressing on shooting age when 1/2 nitrogen fertilizer applied as base fertilizer.Topdressing on earning stage reached higher yield than that on regreening stage on the case of lower nitrogen applied.There was no difference between these two treatments if higher nitrogen applied.Nitrogen plant uptake in 1/2 nitrogen as topdressing treatment was significantly higher than that of all as base fertilizer,which mainly because of improved efficiency of nitrogen fertilizer.31.7%～66.8% of residue nitrogen in soil was distriubuted in 0～40 cm soil layer after harvest and proportion of residue nitrogen in this layer was increased when nitrogen fertilizer applied later.However,in hte treatmet of all nitrogen applied as base fertilizer and topdressing on regreening stage,proportion of residue nitrogen in the subsoil was higher than topduressing in later state,which in 80～100 cm depth was even exceeded that in the topsoil.更多还原