利用NH^(+)_(4)浓度及其同位素值分析西安污染物来源

Using NH^(+)_(4)concentration and its isotope value to analyze the source of pollutants in Xi’an

通过NH^(+)_(4)及δ15N-NH^(+)_(4)分析西安空气质量污染来源。结果表明,气象因素及西安特殊的地理位置可以基本解释NH^(+)_(4)浓度变化。PM2.5≥75μg/m3时期NH^(+)_(4)浓度和δ15N-NH^(+)_(4)值均有大幅增加,导致两者的相关性提高,线性关系为细颗粒(PM2.5)模式下δ15N-NH^(+)_(4)的浓度总体上随NH^(+)_(4)的增加而降低,表明在污染期间NH^(+)_(4)的快速积累与15N的消耗有关。9月NH^(+)_(4)来源主要为农业来源,1月的化石燃料燃烧是NH^(+)_(4)的主导因素,11月的NH^(+)_(4)来源介于两者之间。此结果将为政府制定关于NH3的控制措施提供基础数据,是促进NH3浓度减少工作的基础研究。

The source of air pollution was analyzed in Xi’an through NH andδN-NH.The results show that the meteorological factors and the special geographical location of Xi’an can basically explain the changes in NH concentration.During the period of PM≥75μg/m,both the NH^(+)_(4)concentration and theδN-NH^(+)_(4)value increased significantly,leading to an increase the correlation between the two.The linear relationship is that the concentration ofδN-NH^(+)_(4)in the fine particle(PM)mode generally increases with the increase of NH.The decrease indicates that the rapid accumulation of NH during the pollution period is related to the consumption of N.The sources of NH^(+)_(4)in September were mainly agricultural sources,the burning of fossil fuels in January was the dominant factor of NH^(+)_(4),and the sources of NH^(+)_(4)in November were somewhere in between.The results of this article will provide basic data for the government to formulate NH^(+)_(4)control measures,and will be a basic research to promote the reduction of NH^(+)_(4)concentration.