一次性施肥对春玉米产量和环境效应的影响

采用田间试验，比较了农民习惯施肥、一炮轰和缓释一次施肥3种施肥措施对玉米产量和土壤残留NO3-N以及氮素表观损失的影响，结果表明：不同施肥处理的产量没有显著差异，添加包膜尿素氮肥利用率提高；与播前相比，玉米收获后对照、农民习惯、一炮轰、缓释一次施肥0-90cm土壤剖面NO3-N残留量在低肥力土壤（新立城试验点）的增加量分别为-17.5，104.5，55.7，29.3 kg N/hm2，而在高肥力土壤（布海试验点）都表现为负增长，分别为-44.3，-12.8，-57.2，-51.7 kg N/hm2。农民习惯、一炮轰、缓释一次施肥处理全生育期的氮素表观损失在低肥力点分别为-83，-12，22 kg N/hm2，在高肥力点为172，119，157 kg N/hm2。增加氮肥用量氮素表观损失增加，添加部分缓释氮肥的一次性施肥可以减少收获后土壤剖面NO3-N增量。

Effects of Single Fertilizers Application on Yields and Environment of Spring Maize Production

Field experiments were conducted in higher and lower fertility soil to evaluate effects on maize grain yield, soil residual NO3-N and N apparent losses of three nitrogen management strategies, conventional N splits by farmer, one shot dose fertilization by farmer and single basal application with polymer-coated urea (PCU) as partial N source. The results of two experiment sites showed that there was no significant difference on yields of different N management. Increase of 0-90cm soil residual NO3-N in Xinlicheng site of control, conventional fertilization, one shot does and single application with PCU treatments were -17.5，104.5，55.7，29.3kg N/hm2, and -44.3，-12.8，-57.2，-51.7 kg N/hm2 for higher fertility soil (Buhai site), respectively. The apparent N losses of whole stage were -83，-12，22 kg N/hm2 for lower fertility soil, and 172，119，157 kg N/hm2 for higher soil fertility soil. It indicated that less residual NO3-N increase with treatment of single application with PCU compared with other two strategies, and more apparent N losses resulted from rising of N rate.