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Advances in Earth Science  2019, Vol. 34 Issue (9): 922-935    DOI: 10.11867/j.issn.1001-8166.2019.09.0922
    
Atmospheric Reactive Nitrogen Cycle and Stable Nitrogen Isotope Processes: Progresses and Perspectives
Tao Zhou1,2(),Zhuang Jiang1,2,Lei Geng1,2()
1. Stable Isotope Laboratory of Ice Core and Atmospheric Chemistry,School of Earth and Spaces Sciences,University of Science and Technology of China,Hefei 230026,China
2. Anhui Key Laboratory of Polar Environment and Global Change, Hefei 230026,China
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Abstract  

Oxidized reactive nitrogen in the atmosphere mainly consists of nitrogen oxides (NO X =NO+NO2, NO3) and nitric acid. The atmospheric cycling of NO X influences the formation of ozone and hydroxyl radicals that are important for atmospheric oxidation capacity. Nitric acid, the final product of NO X oxidation, not only is an important component of particulate pollutants, but also has a direct impact on the ecosystem through dry and wet deposition.

The stable nitrogen isotope (δ15N) shows the potential to study reactive nitrogen cycle, and to trace the emission, transport and deposition of reactive nitrogen from local to global scales. Here, we reviewed previous studies using δ15N to investigate NO X emission and atmospheric reactive nitrogen cycle, and discuss the uncertainties of δ15N signatures of different NO X sources from two aspects: NO X generation mechanism and NO X collection methods. We also discussed the nitrogen isotope fractionation and the consequences during the conversions of NO y molecules. We ended up with discussions on the possibility of using δ15N to trace NO X emissions. Although there are still large uncertainties in quantifying and tracing NO X emissions using nitrogen stable isotopes, such isotope tool is efficient enough to trace reactive nitrogen cycles in the atmosphere. On the basis of this, we proposed that we can combine atmospheric chemistry transmission models with isotope tracers to improve our understanding of regional and global atmospheric reactive nitrogen cycle regarding the fluxes of different emission sources, their atmospheric transformation, etc.

Key words:  NO X emission      Atmospheric nitric acid      Reactive nitrogen cycle      Nitrogen stable isotopes.     
Received:  23 June 2019      Published:  15 November 2019
ZTFLH:  P402  
Fund: the National Natural Science Foundation of China “Ice core stable isotope geochemistry” (No. 41822605) and “Atmospheric ozone variability as inferred from isotopic composition of Tibetan snow and ice core nitrate”(41871051)
Corresponding Authors:  Lei Geng     E-mail:  zhoutao7@mail.ustc.edu.cn;genglei@ ustc.edu.cn;genglei@ustc.edu.cn
About author:  Zhou Tao (1996-), female, Feixi County, Anhui Province, Ph.D student. Research areas include reactive nitrogen cycle with stable isotopes. E-mail:zhoutao7@mail.ustc.edu.cn
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Tao Zhou
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Lei Geng

Cite this article: 

Tao Zhou, Zhuang Jiang, Lei Geng. Atmospheric Reactive Nitrogen Cycle and Stable Nitrogen Isotope Processes: Progresses and Perspectives. Advances in Earth Science, 2019, 34(9): 922-935.

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http://www.adearth.ac.cn/EN/10.11867/j.issn.1001-8166.2019.09.0922     OR     http://www.adearth.ac.cn/EN/Y2019/V34/I9/922

Fig.1   δ 15N values of various NO X emission sources
方法名称 收集装置 NO-NO2转化 吸收溶液 收集对象 收集效率
Heaton method[38] 样气被收集到聚乙烯容器后加入NO2吸收溶液 NaOH/H2O2溶液 NO X /
Freyer method[37] 样气通过NO-NO2转化装置后被NO2吸收溶液收集 固态氧化剂CrO3 三乙醇胺溶液 NO2和NO X /
Ammann method[33] 样气依次通过4根管状溶蚀器,分别收集HNO3,HONO,NO2和NO,第四根管子前放置氧化剂 固态氧化剂CrO3/H3PO4 管状溶蚀器附有KOH/愈创木酚的甲醇溶液涂层 NO2和NO /
Li and Wang method[28] 样气通过NO-NO2转化装置后被溶蚀器收集 固态氧化剂CrO3/H3PO4 管状溶蚀器附有KOH/愈创木酚的甲醇溶液涂层 NO /
Modified US EPA method[36,41,42] 样气通过有NO2收集溶液的真空纯净瓶收集 环境中O2 H2SO4/H2O2 NO X >97.5%
被动采样法(Passive samplers[34,35] 基于分子扩散原理,用采样滤膜收集 三乙醇胺滤膜 NO2 /
Figber method[45,65] 样气通过NO X 气体洗涤瓶 KMnO4/NaOH溶液 NO X 100%
动力学通量箱—三乙醇胺法(DFC-TEA method[44] 样气通过NO-NO2转化装置后被NO2吸收溶液收集 过量O3 20%三乙醇胺溶液 NO >98%
Walters method[62] 样气分别通过两根NO2溶蚀器(第一根收集、第二根检测是否收集完全) 管状溶蚀器附有KOH/愈创木酚的甲醇溶液涂层 NO2 /
Table 1  Summary of NO X collection methods
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