应用微气象学水平通量法对太湖流域水稻种植季节不同施肥阶段大气氨排放特征进行监测,并对田间水NH4+-N浓度和pH、土壤NH4+-N浓度和温度、大气风速等参数进行同步观测.结果表明,水稻种植期间,尿素施用后分蘖肥和穗肥时期的氨排放损失率分别为28.47%和14.01%,各时期氨排放通量大小依次为Ⅱ期分蘖肥>Ⅰ期分蘖肥>穗肥,氨挥发持续时间均为7~11 d.田间水NH4+-N浓度是分蘖肥时期影响氨排放水平最主要的因子,决定系数R2达到了0.7454;而风速、土壤NH4+-N浓度、土壤温度是穗肥时期影响氨排放水平的主要影响因子,决定系数R2分别为0.9651、0.7875、0.8960.%Ammonia volatilization was monitored via micrometeorological technique in different fertilization periods in paddy fields of Taihu Lake region. Factors influencing ammonia loss, such as NH4+-N concentration, pH in floodwa-ter, NH4+-N concentration in soil, soil temperature, wind speed, were also studied at the same time. The results in-dicated that ammonia volatilization loss was 28. 47% in the period of tillering-top dressing, and was 14. 01% in ear bearing-top dressing period after urea application. The ammonia volatilization flux after urea application in varied pe-riod decreased as the second period of tillering-top dressing>the first period of tillering-top dressing>ear bearing-top dressing period. Ammonia volatilization lasted 7-11 d. NH4+-N concentration in floodwater was the most important in-fluencing factor in the period of tillering-top dressing, with determination coefficient (R2) of 0. 7454. The important influencing factors in ear bearing-top dressing period included wind speed, NH4+-N concentration in soil and soil tem-perature, with R2 being 0. 9651, 0. 7875 and 0. 8960, respectively.
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