Source Apportionment and Elemental Composition of PM2.5 in Chengdu, China

摘要

In order to investigate the elemental composition of PM2.5 and its sources, PM2.5 samples were collected at an urban site in Chengdu, China. The contents of 20 elements including Al, As, Ba, etc. in PM2.5 were analysed. Enrichment factor, correlation analysis and principal component analysis were applied to analyse the sources of PM2.5. The results showed that the daily mean concentration was 49.2~425.0 μg·m-3 and annual mean concentration was 165.1±84.7 μg·m-3. The element concentrations in winter (7,575.0 ng·m-3) were higher than those in summer (3,326.8 ng·m-3). The results of source apportionment showed that the sources of PM2.5 were soil dust and dust storm, traffic emission, combustion of fossil fuels and coal, and metal smelting in Chengdu. The results of multiple linear regression analysis showed that wind speed and temperature had a negative correlation with most trace elements.