不同水肥制度下稻田氨挥发变化规律

Variation of Ammonia Volatilization in Paddy Field under Different Irrigation and Fertilization Systems

通过田间对比试验,运用通气法观测分析了不同水肥制度下稻田氨挥发的变化规律。结果表明,在中等施氮水平与2次追肥的情况下,早、晚稻氨挥发总量分别为22.56kg/hm2和68.54kg/hm2,分别占当季施氮量的12.5%、38.1%;间歇灌溉模式下的稻田氨挥发总量大于淹灌模式,但差异不显著;穗肥施用后引发的稻田氨挥发量很小,通过把仅追施分蘖肥改为追施分蘖肥和拔节孕穗肥能显著减少稻田氮素氨挥发损失。不论是早稻、中稻还是晚稻,穗肥施用后产生的氮素氨挥发损失占穗肥的比例都明显小于分蘖肥。

Ammonia volatilization processes in paddy field under different irrigation and fertilization systems were measured using venting method through field experiments.The results showed that ammonia volatilization amounts during early rice season and late rice season were 22.56kg/hm2 and 68.54kg/hm2 under middle N level applied by three times,accounting for 12.5% and 38.1% of the applied N,respectively.Compared with flooding irrigation,intermittent irrigation increased ammonia volatilization under the fertilization systems.Ammonia volatilization from rice paddy could be reduced significantly by changing apply basal fertilizer and tiller fertilizer to apply basal fertilizer,tiller fertilizer and panicle fertilizer.N loss via ammonia volatilization after topdressing accounting for the proportion of panicle fertilizer were significantly less than tiller fertilizer during early rice season,middle rice season and late rice season.