The maximum soil ammonium nitrogen content was observed on the 9~(th) day after fertilization(DAF). The soil ammonium concentration was in the order of U > OM > IBDU > GUS > CDU > CK.

• 施肥后9d土壤中铵态氮含量最大,依次为:U>OM>IBDU>GUS>CDU>CK;