Size-resolved chemical composition of atmospheric particles during a straw burning period at Mt. Huang (the Yellow Mountain) of China

Abstract

The particle size spectra and chemical composition of aerosol particles at Mt. Huang (the Yellow Mountain), a background site of southeastern China, were investigated using a single particle aerosol mass spectrometer (SPAMS) and other aerosol monitoring instruments. The field campaign was conducted from Sep. 29 to Oct. 9, 2012, to observe the influence of straw burning on the size distribution, chemical composition of atmospheric aerosols at a background site. Results showed that K-Secondary and K-EC particles were the dominant particle types during this period, with their number concentrations totally accounting for 74% of all the particles. From long-range transport analysis of air masses, six types of particles all contained high concentrations of 39 [K]+ ion (known as the tracer for biomass burning) which indicate that biomass burning may represent as a significant source of aerosols for air masses originated from the north of Mt. Huang. The sampling period could be classified into three sub-periods according to the backward trajectories. During sub-period 1, the K-Secondary particles exhibited the highest concentrations, accounting for 74.2% and 55.4%, respectively, of the submicron and super-micron particles. In sub-period 3, K-EC dominated the submicron particles, indicating that more particles had anthropogenic sources, especially industrial emissions. The results obtained in this study will enrich the database of aerosol chemical composition in the background sites of southeast China and could be of important applications in environmental and climate research.