Abstract: In the February Orchid(Orychophragmus violaceus) /Spring Maize(Zea mays L.)system,ammonia volatilization was investigated by the method of in situ field determination during the basal and top dressing fertiliza-tion periods of spring maize to study the characteristics of ammonia volatilization after the February Orchid was in-corporated into soil asgreen manure. The results showed that the ammonia volatilization amounts ranged from 0.94 kg/ha to 3.27 kg/ha after the basal fertilization,the N loss rates resulted from ammonia volatilization were 1.34%-2.91%,accounting for 3. 12%-6. 80% of the total ammonia volatilization amounts of the whole spring maize sea-son. Under the same nitrogen application levels,the ammonia volatilization amounts of treatments withgreen manure were averagely 1. 04 kg/ha higher than those withoutgreen manure. After top dressing fertilization,the ammonia vol-atilization amounts were 27. 17-46. 81 kg/ha,and the N loss rates caused by ammonia volatilization varied from 34. 50% to 41. 61%,accounting for 93. 20%-96. 88% of the total ammonia volatilization amounts. No obvious differences were observed between the treatments with and withoutgreen manure. Ingeneral,the ammonia volatiliza-tion increased as a result of the N addition,while was little affected by thegreen manure. During the whole spring maize season,total ammonia volatilization amounts ranged from 28.50 kg/ha to 48.32 kg/ha in the treatments of ferti-lization,meanwhile,the N loss rates caused by ammonia volatilization varied from 16.28% to 20.20%.

CLC Number: 

• S142