我国水稻生产的氮肥用量大,肥料氮的利用率不高。从栽培的角度来说,氮肥用量大的主要原因是:(1)基本苗不足,靠增施氮肥促进多发分蘖。(2)氮肥前期用量大,追肥后不中耕,导致氮肥流失严重。(3)中期落水晒田,造成氮肥的挥发损失。氮肥的过量施用不仅增加了生产成本,而且造成了资源 China’s large-scale production of nitrogen fertilizer, nitrogen fertilizer utilization rate is not high. From the cultivation point of view, the main reasons for the large amount of nitrogen fertilizer are: (1) lack of basic seedlings, by increasing nitrogen fertilizer to promote multiple tillers. (2) large amount of nitrogen fertilizer, top dressing, no tillage, resulting in serious loss of nitrogen. (3) mid-term sunning, resulting in the loss of nitrogen volatilization. Excessive application of nitrogen fertilizer not only increases production costs, but also creates resources