1)保氮效果好。把氮肥由表层施改为深施,能大大减少氮肥的挥发损失及反硝化作用。减少杂草和藻类等对肥料的消耗,使氮肥保氮效果好。据测定,把碳酸氢铵球肥深施7～9 cm,在施肥后30 d(天),氮素损失为3.1％,而碳酸氢铵粉肥表施,氮素损失为83.2％。 1) good nitrogen effect. Nitrogen from the top layer applied to the facilities, can greatly reduce the volatilization of nitrogen loss and denitrification. Reduce the consumption of fertilizers, such as weeds and algae, so nitrogen nitrogen effect is good. According to the test, ammonium bicarbonate fertilizer was applied at depths of 7-9 cm. After 30 days of fertilization, the nitrogen loss was 3.1%. However, the ammonium bicarbonate fertilizer was applied on top and the nitrogen loss was 83.2%.