河南省小麦、玉米氮肥需求及节氮潜力

Nitrogen Requirement and Saving Potential for Wheat and Maize in Henan Province

【目的】估算河南省小麦、玉米氮肥需求量和节氮潜力,为河南省及黄淮海区域实现化肥零增长提供依据。【方法】通过统计数据分析河南省小麦、玉米生产和氮肥消费情况及趋势;基于测土配方施肥项目"3414"多年多点试验分析河南省小麦(n=748)和玉米(n=624)氮素累积量及生产单位籽粒的氮素需求;采用肥料效应计算最高产量施氮量和经济最佳施氮量,并在此基础上计算河南省小麦、玉米氮肥需求总量,估算河南省小麦、玉米节氮潜力。【结果】河南省小麦、玉米氮肥总消费量持续增加,单质氮肥消费量呈下降趋势,复混氮肥数量增加。2015年全省小麦、玉米氮肥消费量分别为133.0×10~4 t和60.9×10~4 t。河南省小麦、玉米地上部氮素累积量平均为209.4和183.7 kg·hm^(-2),每生产1 000 kg籽粒的氮素需求量平均为29.1和23.0 kg。肥料效应函数法计算的河南省小麦、玉米最高产量施氮量平均值分别为171.0 kg·hm^(-2)和202.5 kg·hm^(-2);经济最佳施氮量平均分别为155.1和172.8 kg·hm^(-2)。全省小麦氮肥需求总量折纯氮为57.8×10~4—67.7×10~4 t,节氮潜力为21.8×10~4—48.8×10~4 t,节氮16.4%—36.7%;全省玉米氮肥需求总量为42.7×10~4-67.7×10~4 t,节氮潜力最高为18.2×10~4 t,节氮30.0%。【结论】河南省小麦、玉米氮肥消费量与需求量持续增长,当前产量和管理水平下,实际消费量高于需求量;通过合理的氮肥管理,河南省小麦和玉米仍有很大的节氮潜力。

【Objective】 Nitrogen（N） demand and saving potential under recommendation fertilization for the wheat and maize in Henan province were estimated to provide the basis for the policy of zero growth of chemical fertilizer in China.【Method】Based on the statistical data and the field trials, this paper studied the production and N consumption, estimated the N demand and furthermore the saving potential for the wheat and maize production of the whole province under the rational N fertilizer rate according to methods of fertilizer response mode, aboveground N accumulation and N requirements per 1000 kg grain yield.【Result】The N consumption for wheat and maize in Henan province was increased continuously, with the single N fertilizer consumption declining while the N fertilizer in compound and mixed fertilizer increasing. In 2015, the total N consumption for wheat and maize in the total province were 133.0×10^4 t and 60.9×10^4 t, respectively. The aboveground N accumulation for wheat and maize were averagely 209.4 and 183.7 kg·hm^-2, respectively, and N requirement per 1 000 kg grain were 29.1 and 23.0 kg, respectively. The regional mean optimal N fertilizer rate for wheat and maize were 171.0 and 202.5 kg·hm^-2 under the highest yield while 155.1 and 172.8 kg·hm^-2 under the highest economic profit, respectively. The N demand for wheat was 57.8×10^4-67.7×10^4 t, with N saving potential of 21.8×10^4-48.8×10^4 t or 16.4%-36.7% in Henan province; while the N demand for maize was 42.7×10^4-67.7×10^4 t, with the highest N saving potential 18.2×10^4 t or 30.0%. 【Conclusion】The N consumption and demand for wheat and maize in Henan province were increased continuously, however, the actual N consumption exceeded the demand, representing a great potential for fertilizer saving under rational N fertilization in further.