Characteristics of Particulate Matter at Different Pollution Levels in Chengdu, Southwest of China

Atmosphere

Min He¹  Meng Zhang¹  Shijun Ni¹  Huibin Shi¹  Ting Li¹  Jinjin Wang¹  Xin Cheng¹  Scott S. Hughes²  Yi Huang³  Li Wang³ 

[1] Department of Geochemistry, Chengdu University of Technology, Chengdu 610059, China;Department of Geosciences, Idaho State University, Pocatello, ID 83209, USA;State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, China;

关键词: particulate matter;    heavy metals;    Sulfate-Nitrate-Ammonium;    pollution levels;    mobile sources;   

DOI  :  10.3390/atmos12080990

来源: DOAJ

【 摘 要 】

Air pollution is becoming increasingly serious along with social and economic development in the southwest of China. The distribution characteristics of particle matter (PM) were studied in Chengdu from 2016 to 2017, and the changes of PM bearing water-soluble ions and heavy metals and the distribution of secondary ions were analyzed during the haze episode. The results showed that at different pollution levels, heavy metals were more likely to be enriched in fine particles and may be used as a tracer of primary pollution sources. The water-soluble ions in PM_2.5 were mainly Sulfate-Nitrate-Ammonium (SNA) accounting for 43.02%, 24.23%, 23.50%, respectively. SO₄²⁻, NO₃⁻, NH₄⁺ in PM₁₀ accounted for 34.56%, 27.43%, 19.18%, respectively. It was mainly SO₄²⁻ in PM at Clean levels (PM_2.5 = 0~75 μg/m³, PM₁₀ = 0~150 μg/m³), and mainly NH₄⁺ and NO₃⁻ at Light-Medium levels (PM_2.5 = 75~150 μg/m³, PM₁₀ = 150~350 μg/m³). At Heavy levels (PM_2.5 = 150~250 μg/m³, PM₁₀ = 350~420 μg/m³), it is mainly SO₄²⁻ in PM_2.5, and mainly NH₄⁺ and NO₃⁻ in PM₁₀. The contribution of mobile sources to the formation of haze in the study area was significant. SNA had significant contributions to the PM during the haze episode, and more attention should be paid to them in order to improve air quality.

【 授权许可】

Unknown