中文摘要：

利用2006年11～12月、2007年2～3月及2008年5～6月在东海4个航次中采集的33个总悬浮颗粒物样品和7套Anderson分级样品,分析了其中NH 4＋、NO 3-和NO 2-的浓度,探讨了东海气溶胶中氮组分的季节变化和粒径分布.气溶胶中NH 4^＋的浓度为2.6～646.9 nmol·m^-3,冬、春季较高,夏季较低.NO 3-的浓度为5.5～281.5 nmol·m^-3,冬季较高,春、夏季较低.NO 2^-的浓度很低,〈0.5 nmol·m^-3.气溶胶中氮组分的相对贡献具有一定的季节变化趋势,冬季NH 4^＋和NO 3^-的贡献相当,春、夏季以NH 4＋的贡献为主.NO 3-的粒径分布月变化明显,11～12月主要分布在〈2.1μm的细粒子上,2～3月、5～6月分别集中在1.1～4.7μm和2.1～7.0μm的粗粒子上.NH 4＋的粒径分布无明显月季差异,均主要分布在〈1.1μm的细粒子上.后向轨迹分析表明气团的来源和迁移路径显著影响气溶胶中无机氮的分布.气团来自污染较重的陆源,无机氮在大气中的浓度（nmol·m^-3）和在颗粒物中的浓度（μmol·g^-1）均较高;气团来自清洁的海洋源,无机氮在大气中和颗粒物中的浓度均较低.气团起源自陆源但在海上经过长距离的迁移,则无机氮在大气中的浓度相对较低,在颗粒物中的浓度相对较高.

英文摘要：

33 total suspended particle samples and 7 size-segregated particle samples were collected over the East China Sea from Nov.to Dec.,2006,Feb.to Mar.,2007 and May.to Jun.,2008.Concentrations of ammonium,nitrate and nitrite in aerosols were measured to investigate their seasonal variation and size distribution.The concentrations of ammonium in aerosols ranged from 2.6 to 646.9 nmol·m^-3,with the higher values observed in winter and spring,and the lower values in summer.Nitrate concentrations were from 5.5 to 281.5 nmol·m^-3,presenting the seasonal trend of winter 〉spring ≈ summer.The concentrations of nitrite were very low,less than 0.5 nmol·m^-3.The relative contributions of nitrogen species to total nitrogen varied seasonally in some extent.The contribution of nitrate was comparable with that of ammonium in winter,while the contribution of ammonium was the predominant in spring and summer.The size distribution of nitrate presented clear monthly changes.Most of nitrate existed in the fine particles less than 2.1 μm in Nov.to Dec.,and it predominated in the coarse particles with the size of 1.1-4.7 μm and 2.1-7.0 μm,respectively,in Feb.to Mar.and May.to Jun..The size distributions of ammonium in different months were similar,with one peak presenting in the 〈1.1 μm fine particles.The air mass back trajectories analysis indicated that the distributions of inorganic nitrogen in aerosols were significantly influenced by the sources and transport pathways of air mass.Both high nitrogen concentration per unit atmospheric volume（nmol·m^-3） and per unit mass particle（μmol.g^-1） occurred when the air mass passed over severe pollution region.Both low concentration in atmosphere and particle occurred when the air mass came from clean marine atmosphere.Lower concentration in atmosphere and higher concentration in particle occurred when the air mass originated from the continent and transported long distances over the sea.