Nitrogen isotopic composition of free Gly in aerosols at a forest site

• Published in: Atmospheric environment (1994) 2020-02, Vol.222, p.117179, Article 117179
• Main Authors: Zhu, Ren-guo, Xiao, Hua-Yun, Lv, Zhe, Xiao, Hao, Zhang, Zhongyi, zheng, Nengjian, Xiao, Hongwei
• Format: Article
• Language: English
• Subjects: Biomass burning; Fossil fuel; Free glycine; δ15N
• ISSN: 1352-2310; 1873-2844
• DOI: 10.1016/j.atmosenv.2019.117179

The nitrogen isotope composition of free glycine (δ15NF-Gly) in atmospheric particulates from different sources was measured to explore whether δ15NF-Gly could be used to indicate the sources of particulates. We found that the δ15NF-Gly released by biomass combustion (range: +16.9 to +27.3‰) was significantly higher than that from natural sources (up to 21.6‰). The concentration of free Gly in particulates released from fossil fuel combustion (bituminite combustion and vehicle emission) was very low. These results provided the possibility for using the δ15NF-Gly values in aerosol to distinguish biomass combustion from natural sources. In the field, a high correlation between the free Gly concentrations in aerosol and nonsea salt potassium (nss-K+) was observed. The δ15NF-Gly values showed the same temporal pattern with fire points and a link between the δ15NF-Gly values and nss-K+ levels was found. These results suggested that the δ15NF-Gly value in aerosol might be a good indicator for biomass burning. [Display omitted] •Nitrogen isotope of free Gly in total suspended particulates were first reported.•Nitrogen isotope of free Gly in aerosol might be useful for tracing biomass burning.•Bituminous combustion and vehicle emissions may not be the source of free Gly.