淹水条件下的氨挥发研究

在日本“国际农林水产研究中心”实验室用密闭室法测定了淹水条件下不同通气速率、不同温度和尿素施用方法的氨挥发。结果表明,在一定范围内,随着温度和通气速率的提高,氨挥发速率加快,氨挥发量增加;氨挥发高峰一般在施肥后5~8d,施肥18d后基本上检测不出挥发氨;尿素深施混匀有利于降低氨挥发损失,与CaCO3混施因使土壤pH升高而显著增加氨挥发损失,不同施肥处理氨挥发损失积累量占施氮量的26.4%~57.3%,氨挥发是淹水条件下尿素氮损失的主要途径。

Measurements of Ammonia Volatilization from Paddy Soils

Ammonia volatilization was measured with the enclosure method in the laboratory in Japanese International Research Center for Agricultural Sciences (JIRCAS) in 2000. The object was to test the effect of air flow-rate, temperature and application method of urea on ammonia volatilization from paddy soils. The results showed that ammonia volatilization increased with the increase of air flow-rate and temperature. The peak of ammonia volatilization was 5~8 days after urea applied. There was almost not any ammonia volatilization on the 18th day after urea applied. Tillage after application decreased ammonia volatilization. Application CaCO3 before urea increased largely ammonia volatilization because the soil pH increased. The accumulated ammonia loss in the treatments was 26.4%~57.3%. So, ammonia volatilization is the main loss way of urea in paddy soils.