Geochemical characteristics and potential biogeochemical effect of water-soluble ions in atmospheric aerosols over the western boundary regions of Pacific Ocean

We investigated water-soluble ions (WSIs) of aerosol samples collected from 2016 to 2017 in Lanzhou, a typical semi-arid and chemical-industrialized city in Northwest China. WSIs concentration was higher in the heating period (35.68 ± 19.17 μg/m3) and lower in the non-heating period (12.45 ± 4.21 μg/m3). NO3−, SO42−, NH4+ and Ca2+ were dominant WSIs. The concentration of SO42− has decreased in recent years, while the NO3− level was increasing. WSIs concentration was affected by meteorological factors. The sulfur oxidation and nitrogen oxidation ratios (SOR and NOR) exceeded 0.1, inferring the vital contribution of secondary transformation. Meanwhile higher O3 concentration and temperature promoted the homogeneous reaction of SO2. Lower temperature and high relative humidity (RH) were more suitable for heterogeneous reactions of NO2. Three-phase cluster analysis illustrated that the anthropogenic source ions and natural source ions were dominant WSIs during the heating and non-heating periods, respectively. The backward trajectory analysis and the potential source contribution function model indicated that Lanzhou was strongly influenced by the Hexi Corridor, northeastern Qinghai–Tibetan Plateau, northern Qinghai province, Inner Mongolia Plateau and its surrounding cities. This research will improve our understanding of the air quality and pollutant sources in the industrial environment.

Download Full-text

Insights into measurements of water-soluble ions in PM2.5 and their gaseous precursors in Beijing

Journal of Environmental Sciences ◽

10.1016/j.jes.2020.08.031 ◽

2021 ◽

Vol 102 ◽

pp. 123-137

Author(s):

Jie Su ◽

Pusheng Zhao ◽

Jing Ding ◽

Xiang Du ◽

Youjun Dou

Keyword(s):

Water Soluble ◽

Soluble Ions ◽

Water Soluble Ions

Download Full-text

Characterization of Ambient Particulate Matters in an Industry-Intensive Area in Central Taiwan

Atmosphere ◽

10.3390/atmos12070926 ◽

2021 ◽

Vol 12 (7) ◽

pp. 926

Author(s):

Hsing-Wang Li ◽

Kang-Shin Chen ◽

Chia-Hsiang Lai ◽

Ting-Yu Chen ◽

Yi-Ching Lin ◽

...

Keyword(s):

Principal Component Analysis ◽

Principal Component ◽

Component Analysis ◽

Water Soluble ◽

High Tech ◽

Particulate Matters ◽

Metallic Elements ◽

Soluble Ions ◽

Water Soluble Ions ◽

Central Taiwan

Atmospheric particulate matters (PMs) were measured in an industry-intensive region in central Taiwan in order to investigate the characteristics and possible sources of PMs. The samplings were simultaneously conducted using a 10- and 3-stage Micro Orifice Uniform Deposit Impactor (MOUDI) from 2017 to 2018. In this study, the characteristics of PMs in this region were evaluated by measuring the mass concentration of PMs and analyzing water-soluble ions and metallic elements, as well as dioxins. Additionally, principal component analysis (PCA) was used to identify the potential sources of PMs. The results showed that the mean concentration of coarse (>1.8 μm), fine (0.1–1.8 μm), and ultrafine (<0.1 μm) particles were 13.60, 14.38, and 3.44 μg/m3, respectively. In the industry-intensive region, the size distribution of ambient particles showed a bi-modal distribution with a high concentration of coarse particles in the spring and summer, while fine particles were dominant in the autumn and winter. The most abundant water-soluble ions of PMs were NO3−, Cl−, and SO42−, while the majority of metallic elements were Na, Fe, Ca, Al, and Mg in different particle sizes. The results of Pearson’s correlation analysis for metals indicated that the particles in the collected air samples were related to the iron and steelmaking industries, coal burning, vehicle exhausts, and high-tech industries. The dioxin concentration ranged from 0.0006 to 0.0017 pg I-TEQ/Nm3. Principal component analysis (PCA) revealed that the contribution to PMs was associated with sea salt, secondary pollutants, and industrial process.

Download Full-text