不同氮肥运筹对东北春玉米氮素吸收和土壤氮素平衡的影响

Effect of the Nitrogen Application to Spring Maize Nitrogen Absorption and Soil Nitrogen Balance in Northeast of China

在吉林省榆树市粮食高产示范区,以先玉335为试验材料,通过田间试验研究不同氮肥运筹对春玉米的生长、产量及土壤氮素平衡的影响。结果表明,适宜氮肥运筹方式能显著提高玉米产量,施氮量200 kg/hm2,全部用作基肥不追肥(基追比1∶0)处理前期氮素供应过量,导致氮素向子粒转运量减少,过多保留在营养体中,致使产量和氮素利用效率相对其他处理较低;氮肥1/5基施,2/5拔节期追施,2/5大喇叭口期追施(基追比为1∶2∶2)的处理有较高的氮肥农学利用率、氮肥利用率和氮肥偏生产力。玉米生育期田间氮肥的表观损失主要由一次性过量施肥造成,增大拔节后追肥比例增加了收获后土壤的无机氮残留。对氮肥的调控应结合作物养分不同阶段需求及土壤养分供应,达到玉米高产和提高氮肥利用效率,减少氮肥损失对环境带来的危害。

The field experiments were conducted to investigate the effects of different nitrogen（N） application on spring maize growth, grain yield and the change of soil N content in Yushu, Jilin province. The results showed that the appropriate Nitrogen application can significantly increase grain yield, N 200 kg/ha at the ratio of 1 ： 0 （basal N and topdressing N） treatment oversupply nitrogen at early growing season, cause to turn on the nitrogen was reduced. Ex- cessively retained in the plant, the yield and nitrogen use efficiency is poorer than other treatments, N 200 kg/ha at the ratio of 1 ： 2 ： 2 treatments obtain higher nitrogen agriculture utilization, nitrogen utilization efficiency and nitrogen partial productivity. The reason of maize growth period in the field of the apparent nitrogen loss is one-time applying fertilizer excessively, while high topdressing N rates after elongation stage also increase soil N residual after the har- vest. So in order to achieve high maize yield and improve nitrogen use efficiency, nitrogen fertilizer control should be combined with crop nutrient demand at different stages, soil nutrient supply, in order to reduce the harm by nitrogen fertilizer losses to the environment.