Next Article in Journal
The Impacts of Taklimakan Dust Events on Chinese Urban Air Quality in 2015
Previous Article in Journal
The Hot-Dry-Windy Index: A New Fire Weather Index
Article Menu
Issue 7 (July) cover image

Export Article

Open AccessArticle
Atmosphere 2018, 9(7), 280;

Analysis of Compositional Variation and Source Characteristics of Water-Soluble Ions in PM2.5 during Several Winter-Haze Pollution Episodes in Shenyang, China

Institute of Atmospheric Environment, China Meteorological Administration, Shenyang 110166, China
Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China
Dalian Academy of Agriculture Sciences, Dalian 116036, China
Author to whom correspondence should be addressed.
Received: 26 April 2018 / Revised: 11 July 2018 / Accepted: 12 July 2018 / Published: 19 July 2018
(This article belongs to the Section Aerosols)
Full-Text   |   PDF [2961 KB, uploaded 20 July 2018]   |  


From 18 February to 13 March 2014 and from 17 December 2016 to 27 January 2017, an online analyzer for monitoring aerosols and gases (MARGA) and an online single particle aerosol mass spectrometer (SPAMS) were used to measure and analyze the concentrations and sources of water-soluble (WS) ions in PM10, PM2.5, and gases (NH3, HNO3, HCl), in Shenyang City, China. During the field campaign, nine haze episodes (or smog episodes, total 582 h) were identified, with 960 identified as non-haze periods. The average mass concentrations of PM2.5 and total water-soluble ions (TWSIs) in PM2.5 during haze episodes were 131 μg·m−3 and 77.2 μg·m−3, 2.3 times and 1.9 times the values in non-haze periods, respectively. The average mass concentration of TWSIs in PM2.5 was 55.9 μg·m−3 (accounting for 55.9% of PM2.5 mass loading), 37.6% of which was sulfate, 31.7% nitrate, 20.0% ammonium, 6.6% chloride, 1.9% potassium, 1.4% calcium, and 0.8% magnesium throughout the campaign. Concentrations of sulfate, nitrate, and ammonium (SNA) secondary pollution ions increased rapidly during haze episodes to as much as 2.2 times, 3.0 times, and 2.4 times higher than during non-haze periods, respectively. Diurnal variations during non-haze periods were significant, while complex pollution was insignificant. Based on changes in the backward trajectories and concentrations of WS ions, the hazy episodes were divided into three types: complex, coal-burning, and automobile exhaust pollution. All complex episodes had high concentrations and greater contributions of ammonium nitrate from complex and automobile exhaust pollution, while the contribution of ammonium sulfate from coal-burning pollution was greater than that of ammonium nitrate. The correlation coefficients among SNA species were very high in complex pollution, with nitrate and sulfate the main forms present. The results of principal component analysis (PCA) were related to emissions from burning coal for heating and from long-range transmission in winter. In the case of exhaust pollution, NO3 accounted for the highest percentage of PM2.5, and NH4+ was more closely related to NO3 than to SO42−. Coal-burning pollution was the most common type of pollution in Shenyang. The contribution of sulfate was higher than that of nitrate. Based on PCA, the contribution of coal-burning emissions varied from 36.7% to 53.6% due to industry, soil sources, and other factors. View Full-Text
Keywords: haze; MARGA; PM2.5; SPAMS; water-soluble ions haze; MARGA; PM2.5; SPAMS; water-soluble ions

Figure 1

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).

Share & Cite This Article

MDPI and ACS Style

Hong, Y.; Li, C.; Li, X.; Ma, Y.; Zhang, Y.; Zhou, D.; Wang, Y.; Liu, N.; Chang, X. Analysis of Compositional Variation and Source Characteristics of Water-Soluble Ions in PM2.5 during Several Winter-Haze Pollution Episodes in Shenyang, China. Atmosphere 2018, 9, 280.

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