气候变化领域集成服务门户(CCPortal): Quantifying major NOx sources of aerosol nitrate in Hangzhou, China, by using stable isotopes and a Bayesian isotope mixing model

CCPortal

DOI	10.1016/j.atmosenv.2020.117979
	Quantifying major NOx sources of aerosol nitrate in Hangzhou, China, by using stable isotopes and a Bayesian isotope mixing model
	Jin Z.; Qian L.; Shi Y.; Fu G.; Li G.; Li F.
发表日期	2021
ISSN	13522310
卷号	244
英文摘要	Nitrogen oxides (NOx) from anthropogenic emissions oxidized to form nitrate (NO3−) and play a key role in air pollution. The aim of this study is to identify the NOx sources and their seasonal variations in Hangzhou, a typical city in East China. To achieve this, the chemical characteristics of water-soluble inorganic ions (WSIIs) and the stable isotopes of NO3− (δ15N–NO3- and δ18O–NO3-) were measured in fine particulate matter (PM2.5) and total suspended particle (TSP) aerosol samples that were collected between December 2018 and November 2019. It was found that the annual average concentration of PM2.5 (69.28 ± 34.69 μg/m3) in Hangzhou exceeded the Chinese air quality limit of 35.00 μg/m3. The results showed that NO3− accounted for the largest proportion of the WSIIs in both PM2.5 and TSP, and that major ions were mainly in the form of NH4NO3, (NH4)2SO4, Ca(NO3)2, CaSO4 in aerosol particles. High ratios of NO3−/SO42− in PM2.5 and TSP indicated that vehicle emissions became increasingly important source of aerosol pollution in Hangzhou during the study period. The δ15N–NO3- values ranged from +1.1‰ to +9.2‰ in PM2.5 and from −1.0‰ to +8.5‰ in TSP in Hangzhou. A Bayesian isotopic mixing model (stable isotope analysis in R (SIAR)) was applied to quantify the NOx sources in Hangzhou. This revealed that vehicle emissions, coal combustion and biomass burning were the main NOx sources of PM2.5 and TSP. The seasonal variation of the δ15N–NO3- values in PM2.5 and TSP in the study area were due to seasonal changes in the NOx contributions from different sources. The SIAR model results indicated that coal combustion increased in association with heating in north China during the winter (winter: 38.4% for PM2.5 and 36.4% for TSP, summer: 30.6% for PM2.5 and 29.8% for TSP) and the microbial N cycle increased with a higher application of fertilizer to crops during the summer (winter: 5.3% for PM2.5 and 5.6% for TSP, summer: 10.7% for PM2.5 and 11.6% for TSP). The improved SIAR model combined with the equilibrium fractionation reported the lower contributions from coal combustion (15.5–20.2%) and the higher contributions from Microbial N cycle (22.9–29.3%), as compared to the SIAR model. The seasonal variation of the δ18O–NO3- values was influenced by differences in the oxidation of NO2 via O3 (forming HNO3), whereby the N2O5 pathway dominated during the winter and the OH pathway dominated during the summer. © 2020 Elsevier Ltd
英文关键词	Aerosol; Nitrate; Nitrogen and oxygen isotopes; SIAR model; Water-soluble inorganic ion
语种	英语
scopus关键词	Aerosols; Air quality; Calcium compounds; Coal; Isotopes; Mixing; Nitrates; Nitrogen oxides; Sulfate minerals; Annual average concentration; Anthropogenic emissions; Application of fertilizers; Chemical characteristic; Equilibrium fractionations; Fine particulate matter (PM2.5); Total suspended particles; Water soluble inorganic ions; Coal combustion; nitrate; nitric oxide; stable isotope; aerosol; air quality; biomass burning; coal combustion; isotopic fractionation; model; nitrate; nitric oxide; particulate matter; seasonal variation; stable isotope; aerosol; air pollutant; air quality; Article; China; combustion; controlled study; denitrifying bacterium; exhaust gas; humidity; isotope analysis; nonhuman; particulate matter 2.5; priority journal; Pseudomonas aureofaciens; seasonal variation; urbanization; China; Hangzhou; Zhejiang
来源期刊	Atmospheric Environment
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/152969
作者单位	College of Environment, Zhejiang University of Technology, Hangzhou, 310032, China
推荐引用方式 GB/T 7714	Jin Z.,Qian L.,Shi Y.,et al. Quantifying major NOx sources of aerosol nitrate in Hangzhou, China, by using stable isotopes and a Bayesian isotope mixing model[J],2021,244.
APA	Jin Z.,Qian L.,Shi Y.,Fu G.,Li G.,&Li F..(2021).Quantifying major NOx sources of aerosol nitrate in Hangzhou, China, by using stable isotopes and a Bayesian isotope mixing model.Atmospheric Environment,244.
MLA	Jin Z.,et al."Quantifying major NOx sources of aerosol nitrate in Hangzhou, China, by using stable isotopes and a Bayesian isotope mixing model".Atmospheric Environment 244(2021).