Added S0 and DCD could inhibit nitrification of soil NH4+, decrease soil NO3--N content, and maintain a high soil NH4+-N content within 72 days at NH4HCO3 treatment, and within 48days at urea treatment.

• S~0、DCD及其组合施入土壤可抑制NH_4~+向NO_3~-的转化，降低土壤NO_3~- -N水平，使土壤内NH_4~+ -N长时间保持较高水平。