热带—亚热带多雨湿润区旱地土壤尿素氨挥发研究

Study on Ammonia Loss by Volatilization for Urea Fertilized to Dry Land in the Tropics and Subtropics

研究了旱地赤红壤类土壤尿素施用量和施用深度对氨挥发损失的影响。结果表明,随氮肥用量增加,氨挥发量增大,氨挥发率在每公顷施氮450kg时,达最大值;随氮肥施用深度增加,氨挥发量和挥发率均减小,施肥深度为6cm时,氨挥发损失已很小,可忽略不计;氨挥发作用主要发生在施肥后30d内,但增大施氮量和施肥深度都会使氨挥发持续时间延长。

The effects of different application rates of urea - nitrogen and fertilization depths on ammonia loss by volatilization were studied in two crimson soils. The results indicate that both nitrogen application rate and fertilization depth are the main factors of affecting ammonia volatilization. The more amount of ammonia volatilized from soil, and the more application rate of nitrogen adding. The maximum of ammonia volatilization percent occurred when the application rate reach 450 kgN/ha, and it decreases along with the fertilization depth increasing. When the fertilization is 6 cm in depth, the amounts of ammonia volatilized from two soil are very little, which can be neglected. Ammonia loss by volatilization is mainly occurred in 30 days after fertilization, but both increasing nitrogen rate and fertilization depth will prolong the ammonia volatilization period.