[Characteristics and Source Apportionment of Carbonaceous Aerosols in the Typical Urban Areas in Chongqing During Winter]

Chao Peng; Zhen-Liang Li; Ying Xiang; Xiao-Chen Wang; Ling-Tao Wang; Sheng Zhang; Chong-Zhi Zhai; Yang Chen; Fu-Mo Yang; Tian-Yu Zhai

doi:10.13227/j.hjkx.202302166

[Characteristics and Source Apportionment of Carbonaceous Aerosols in the Typical Urban Areas in Chongqing During Winter]

Huan Jing Ke Xue. 2024 Jan 8;45(1):48-60. doi: 10.13227/j.hjkx.202302166.

[Article in Chinese]

Authors

Chao Peng^{1

2

3}, Zhen-Liang Li^{1

2

3}, Ying Xiang^{1

2

3}, Xiao-Chen Wang^{1

2

3}, Ling-Tao Wang^{1

2

3}, Sheng Zhang^{1

2

3}, Chong-Zhi Zhai^{1

2

3}, Yang Chen⁴, Fu-Mo Yang⁵, Tian-Yu Zhai⁶

Affiliations

¹ Chongqing Academy of Eco-Environmental Science, Chongqing 401147, China.
² Chongqing Branch Academy of Chinese Research Academy of Environmental Sciences, Chongqing 401147, China.
³ Key Laboratory for Urban Atmospheric Environment Integrated Observation & Pollution Prevention and Control of Chongqing, Chongqing 401147, China.
⁴ Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
⁵ College of Architecture and Environment, Sichuan University, Chengdu 610065, China.
⁶ College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.

PMID: 38216457
DOI: 10.13227/j.hjkx.202302166

Abstract

To investigate the characteristics, source apportionment, and potential source areas of carbonaceous aerosols in Chongqing during winter, PM_2.5 samples were collected from January 2021 to February 2021 in the urban areas of Wanzhou (WZ), Yubei (YB), and Shuangqiao (SQ). The results showed that the average mass concentrations of PM_2.5, OC, and EC in SQ were (72.6 ±33.3), (18.2 ±8.2), and (4.4 ±1.7) μg·m^-3, respectively, higher than those in WZ[(67.2 ±30.3), (17.2 ±7.4), and (5.1 ±2.4) μg·m^-3] and YB[(63.4 ±25.7), (15.4 ±6.3), and (4.2 ±1.9) μg·m^-3]. Compared with that during the clear period, the concentration and fraction of EC in total carbon increased by 103.0% and 8.1%, respectively, in WZ compared to that in other areas during pollution period, whereas the OC/EC ratio was decreased significantly (-10.5%), indicating that the primary emission of carbonaceous aerosols increased significantly during the pollution period. The average mass concentrations of secondary organic carbon (SOC) in SQ and YB were (7.7 ±4.8) μg·m^-3 and (6.9 ±2.8) μg·m^-3 significantly higher, respectively, than that in WZ[(4.5 ±1.9) μg·m^-3] during the campaign. This indicated that the secondary transformation had a greater influence on the carbonaceous aerosols in SQ and YB than that in WZ. Furthermore, in contrast to that in WZ, the ratios of SOC/OC were increased with the increase in PM_2.5 concentrations, and significant correlations between SOC concentration and aerosol water content, NO₂ concentration, and the value of NOR were observed in SQ and YB (P < 0.01), indicating that the increasing of carbonaceous aerosol concentrations might be mainly driven by the SOC with -NO₂ groups produced by aqueous chemical reactions during winter in SQ and YB. The positive definite matrix factor (PMF) results in these urban areas showed that the contribution of biomass/coal combustion source in WZ (47.4%) was significantly higher than that in YB (34.2%) and SQ (38.1%), whereas the gasoline motor vehicle emission and secondary transformation impacts were more significant in YB. The results of the concentration weighted trajectory (CWT) showed that the potential sources of carbonaceous aerosols were mainly the local and northeastern parts of these urban areas (such as Changshou).

Keywords: Chongqing; carbonaceous aerosols; pollution period; secondary organic carbon; source apportionment.

Publication types

English Abstract