Study on Seasonal Characteristics of the Elements of PM2.5 in Harbin

In order to investigate the seasonal characteristic of PM2.5, PM2.5 were collected in four seasons. This study investigates the elemental characteristics of PM2.5. The results show that the distribution trends of Ca, Na, and Mg are consistent and they are the highest in summer, lowest in winter. S is lower in summer and higher in autumn and winter, which is also caused by heating in autumn and winter. Si is higher in winter and lower in autumn, fly ash emissions from coal combustion is the main reason. Zn and K have a significant seasonal variation which is influenced by environmental factors in different seasons. Al and Fe mainly come from industrial emissions and natural emissions, Al is higher in summer and lower in winter, Fe is higher in winter lower in autumn. Cu, Cr, Cd, Ni, Mn, Sr, V, As, and Ba concentrations have lower content in four seasons, which indicates that emissions sources of these elements are more stable.