Next Article in Journal
Simulating the Effects of Urban Parameterizations on the Passage of a Cold Front During a Pollution Episode in Megacity Shanghai
Next Article in Special Issue
Inferring Fine-Mode and Coarse-Mode Aerosol Complex Refractive Indices from AERONET Inversion Products over China
Previous Article in Journal
Effect of Vertical Air Motion on Disdrometer Derived Z-R Coefficients
Previous Article in Special Issue
Occurrence and Reverse Transport of Severe Dust Storms Associated with Synoptic Weather in East Asia
Article Menu
Issue 2 (February) cover image

Export Article

Open AccessArticle

Characteristics and Sources of Water-Soluble Ions in PM2.5 in the Sichuan Basin, China

School of Safety and Environmental Engineering, Capital University of Economics and Business, NO.121 Zhangjialukou Rd, Fengtai District, Beijing 100070, China
College of Environmental Science and Engineering, Peking University, NO.5 Yiheyuan Rd, Haidian District, Beijing 100871, China
Sichuan Provincial Environmental Monitoring Center, NO.88 3rd East Guanghua Rd, Qingyang Districat, Chengdu 610041, China
Chongqing Environmental Monitoring Center, NO.252 Qishan Rd, Yubei District, Chongqing 401147, China
Author to whom correspondence should be addressed.
Atmosphere 2019, 10(2), 78;
Received: 19 January 2019 / Revised: 4 February 2019 / Accepted: 7 February 2019 / Published: 15 February 2019
(This article belongs to the Special Issue Atmospheric Aerosol Regional Monitoring)
PDF [2429 KB, uploaded 15 February 2019]


To track the particulate pollution in Sichuan Basin, sample filters were collected in three urban sites. Characteristics of water-soluble inorganic ions (WSIIs) were explored and their sources were analyzed by principal component analysis (PCA). During 2012–2013, the PM2.5 concentrations were 86.7 ± 49.7 μg m−3 in Chengdu (CD), 78.6 ± 36.8 μg m−3 in Neijiang (NJ), and 71.7 ± 36.9 μg m−3 in Chongqing (CQ), respectively. WSIIs contributed about 50% to PM2.5, and 90% of them were secondary inorganic ions. NH4+ and NO3 roughly followed the seasonal pattern of PM2.5 variations, whereas the highest levels of SO42− appeared in summer and autumn. PM2.5 samples were most acidic in autumn and winter, but were alkaline in spring. The aerosol acidity increased with the increasing level of anion equivalents. SO42− primarily existed in the form of (NH4)2SO4. Full neutralization of NH4+ to NO3 was only observed in low levels of SO42− + NO3, and NO3 existed in various forms. SO42− and NO3 were formed mainly through homogeneous reactions, and there was the existence of heterogeneous reactions under high relative humidity. The main identified sources of WSIIs included coal combustion, biomass burning, and construction dust. View Full-Text
Keywords: PM2.5; water-soluble ions; sources; Sichuan Basin PM2.5; water-soluble ions; sources; Sichuan Basin

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Supplementary material


Share & Cite This Article

MDPI and ACS Style

Chen, Y.; Xie, S.-D.; Luo, B.; Zhai, C. Characteristics and Sources of Water-Soluble Ions in PM2.5 in the Sichuan Basin, China. Atmosphere 2019, 10, 78.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Atmosphere EISSN 2073-4433 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top