Quantification of NOx sources contribution to ambient nitrate aerosol, uncertainty analysis and sensitivity analysis in a megacity

被引：2

作者：

Zhang, Wenhui ^{[1
,2
]}

Wu, Fuliang ^{[1
,2
]}

Luo, Xi ^{[1
,2
]}

Song, Lilai ^{[1
,2
]}

Wang, Xuehan ^{[1
,2
]}

Zhang, Yufen ^{[1
,2
]}

Wu, Jianhui ^{[1
,2
]}

Xiao, Zhimei ^{[3
]}

Cao, Fang ^{[4
]}

Bi, Xiaohui ^{[1
,2
]}

Feng, Yinchang ^{[1
,2
]}

机构：

[1] Nankai Univ, Coll Environm Sci & Engn, State Environm Protect Key Lab Urban Ambient Air P, Tianjin 300350, Peoples R China

[2] Nankai Univ, China Meteorol Adm Nankai Univ CMA NKU Cooperat La, Coll Environm Sci & Engn, Tianjin 300350, Peoples R China

[3] Tianjin Ecoenvironm Monitoring Ctr, Tianjin 300191, Peoples R China

[4] Nanjing Univ Informat Sci & Technol, Yale NUIST Ctr Atmospher Environm, Int Joint Lab Climate & Environm Change, Nanjing 210044, Peoples R China

来源：

SCIENCE OF THE TOTAL ENVIRONMENT | 2024年 / 926卷

关键词：

Nitrate aerosol; Dual isotopes; Source contribution; Uncertainty analysis; Sensitivity analysis; NITROGEN ISOTOPIC COMPOSITION; TRACE GAS EMISSIONS; THEORETICAL CALCULATION; RADICAL CONCENTRATIONS; FRACTIONATION FACTORS; REACTIVE NITROGEN; POWER-PLANTS; POLLUTION; SOIL; PHOTOCHEMISTRY;

D O I：

10.1016/j.scitotenv.2024.171583

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

Dual isotopes of nitrogen and oxygen of NO3- are crucial tools for quantifying the formation pathways and precursor NOx sources contributing to atmospheric nitrate. However, further research is needed to reduce the uncertainty associated with NOx proportional contributions. The acquisition of nitrogen isotopic composition from NOx emission sources lacks regulation, and its impact on the accuracy of contribution results remains unexplored. This study identifies key influencing factors of source isotopic composition through statistical methods, based on a detailed summary of delta N-15-NOx values from various sources. NOx emission sources are classified considering these factors, and representative means, standard deviations, and 95 % confidence intervals are determined using the bootstrap method. During the sampling period in Tianjin in 2022, the proportional nitrate formation pathways varied between sites. For suburban and coastal sites, the ranking was f(P1)(NO2 + OH radical) > f(P2)(N2O5 + H2O) > f(P3)(NO3 + DMS/HC), while the rural site exhibited similar fractional contributions from all three formation pathways. Fossil fuel NOx sources consistently contributed more than non-fossil NOx sources in each season among three sites. The uncertainties in proportional contributions varied among different sources, with coal combustion and biogenic soil emission showing lower uncertainties, suggesting more stable proportional contributions than other sources. The sensitivity analysis clearly identifies that the isotopic composition of N-15-enriched and N-15-reduced sources significantly influences source contribution results, emphasizing the importance of accurately characterizing the localized and time-efficient nitrogen isotopic composition of NOx emission sources. In conclusion, this research sheds light on the importance of addressing uncertainties in NOx proportional contributions and emphasizes the need for further exploration of nitrogen isotopic composition from NOx emission sources for accurate atmospheric nitrate studies.

引用

页数：15