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美国纽约在氮平衡及肥料管理方法上进行了统计和指导,结果如下:①2007年,纽约非豆科作物的全氮平衡为62 kg/hm2;②全州N平衡呈下降趋势,从1987年的125 kg/hm2降到2007年的62 kg/hm2,主要原因是1987～1992年间N肥使用的下降。③如果考虑贮藏系统中粪肥N损失和应用时N损失时,全州N平衡降到-38kg/hm2。④假设近乎0的P平衡,一个负的N平衡表明,增加粪肥和肥料N的使用效率或增加其他N来源,如覆盖作物、依靠N固定,短期轮作等管理手段是需要的,可降低N排放量,减少N损失到环境中去。降低贮藏间N损失,增加粪肥和肥料N的吸收效率对纽约农业的可持续发展是重要的。
New York, USA conducted statistics and guidance on nitrogen balance and fertilizer management methods. The results are as follows: ① In 2007, the total nitrogen balance of non-legume crops in New York City was 62 kg / hm2; ② The statewide N balance showed a downward trend. From 1987 125 kg / hm2 dropped to 62 kg / hm2 in 2007, mainly due to the decline of N fertilizer use from 1987 to 1992. (3) When considering the loss of manure N in the storage system and the N loss in use, the statewide N balance is reduced to -38 kg / hm2. Assuming a near-zero P-balance, a negative N-balance suggests that increasing manure and fertilizer N use efficiency or adding other sources of N such as crop cover, reliance on N-fixed, short-term rotation and other management measures are needed to reduce N-emissions Reduce the amount of N lost to the environment. Reducing N losses in storage and increasing the efficiency of manure and fertilizer N absorption are important to the sustainable development of agriculture in New York.