Characterization of aerosol chemical properties from near-source biomass burning in the northern Indochina during 7-SEAS/Dongsha experiment

► The first aerosol characterization for near-source biomass burning in Indochina. ► Organic carbon is the most abundant aerosol component. ► The percentage of K+ in PM2.5 is higher than in other ambient studies. ► PM2.5 K+, levoglucosan, EC1-OP, and OC3 are good BB tracers near sources. ► The collected aerosol was inferred from the smoldering state of softwood burning.