不同秸秆添加物对尿素氨挥发的影响

Effect of Straws on Ammonia Volatilization Loss from Urea

采用土壤与粉碎秸秆混合物室内氨挥发模拟试验,研究了不同秸秆添加物对尿素氨挥发的影响。结果表明,施用等量尿素,不同秸秆混合条件下尿素氨挥发损失具有明显差异;添加小麦或玉米秸秆,尿素在施入土壤后的第2天达到挥发高峰,而仅施用尿素的土壤在第3天达到挥发高峰;施肥后氨挥发损失总量为尿素>尿素+玉米秸秆>尿素+小麦秸秆;不同处理氨挥发损失量与土壤pH值和土壤无机氮含量具有显著相关性。

Effects of amending urea with wheat straw or corn straw at different soil moisture on ammonia volatilization in soil were measured. NH3 volatilization from incorporated-applied urea fertilizers was measured using a sponge-tripping and KCl-extraction method. Kinetics of NH3 volatilization over a 10day period showed that the peak of NH3 loss was on day 3 with amended urea alone, whilst it occurred on day 2 with amended urea and straws together. Total NH3 loss under the experimental conditions decreased in order urea 〉 urea ＋ maize straw 〉 urea ＋ wheat straw. The higher soil moisture, the less ammonia volatilization did. The correlation analysis showed that ammonia volatilization was significantly affected by pH of surface soil. Thus, application of urea fertilizer to farm should consider the characteristic of straws in different soil moisture so as to reduce ammonia losses.