农业环境科学学报2017，Vol.36Issue(2)：401-408,8.DOI:10.11654/jaes.2016-1233
施氮水平对冬小麦冠层氨挥发的影响
Ammonia volatilization of winter wheat canopy under different nitrogen rates
摘要
Abstract
A single factor field experiment with three nitrogen rates (0,90,and 180 kg N· hm-2) was conducted in winter wheat during the 2015-2016 growth season.Ammonia volatilization from both soil and canopy in winter wheat field were measured with the modified vented ammonia trap chambers.Glutamine synthetase (GS) activity in leaves,apoplastic NH4+ concentration and pH,and ammonia compensation point were determined simultaneously.Obtained results showed that field ammonia volatilization mainly occurred within the 2～3 weeks after N fertilization.In the whole growing season,ammonia volatilization totaled in 3.773～8.704 kg N· hm 2,and it increased significantly with the increase of N fertilization rates,of which 3.289～7.773 kg N·hm-2 were from soil,accounting for 87.2％～89.3％ of the total;and 0.750～1.461 kg N·hm-2 from the canopy,accounting for 15.4％～19.9％ of the total.It was found that the canopy absorbed volatilized ammonia during seedling stage under lower nitrogen application rate (90 kg N· hm-2),and during seedling,returning green and early grain filling stage under higher N application rate (180 kg N· hm-2),but did not under no N fertilization.The net canopy ammonia volatilization mainly occurred at flowering and late grain filling stage,accounting for 4.5％～9.3％ and 79.1％～99.0％ of total canopy ammonia volatilization during the whole growing season,respectively.Canopy ammonia fluxes were positively correlated with the ammonia compensation point and apoplastic NH4+ concentration,but showed no relation to the GS activity in leaves and apoplastic pH.In summary,winter wheat canopy volatilizes ammonia to the atmosphere past flowering no matter fertilization or not,but it absorbs ammonia from the atmosphere with N fertilization,and emits ammonia without N fertilization during the vegetative stages.关键词
冠层氨挥发/冬小麦/质外体NH4+浓度/氨气补偿点/谷氨酰胺合成酶(GS)Key words
canopy ammonia volatilization/winter wheat/apoplastic NH4+ concentration/ammonia compensation point/glutamine synthetase (GS)分类
农业科技引用本文复制引用
景建元,孙晓,杨阳,李娜,田肖肖,吕慎强,王林权..施氮水平对冬小麦冠层氨挥发的影响[J].农业环境科学学报,2017,36(2):401-408,8.基金项目
国家公益性行业(农业)科研专项(201503124)The Special Fund for Ago-scientific Research in the Public Interest of China(201503124) （农业）
