氮是植物需求量最大的矿质营养元素。土壤供氮不足是引起农产品产量下降和品质降低的主要因子,同时氮肥施用过剩会造成江湖水体富营养化,地下水硝态氮(NO_3~-—N)积累及毒害等。我国是氮肥施用量和生产量最大的国家,目前我国氮肥利用率约30%～35%,损失严重,在稻 Nitrogen is the mineral nutrient with the highest plant demand. Inadequate supply of nitrogen is the main factor that causes the decline of yield and quality of agricultural products. At the same time, excess nitrogen fertilizer will cause the eutrophication of rivers and lakes and accumulation of nitrate nitrogen (NO_3 ~ -N) in groundwater and poisoning. China is the largest amount of nitrogen fertilizer production and production countries, at present, China’s nitrogen utilization rate of about 30% to 35%, the loss of serious, in the rice