Microbial population structure in near-ground aerosols during fog-haze days in northern China

Studies on microbial populations in near-ground aerosols during fog–haze days could help enhance our knowledge concerning the relationship between fog–haze and human health. In this study, microbial populations in aerosols near-ground during a fog–haze event in Beijing were analyzed using clone library methods. Results showed that the bacterial diversity in aerosols during fog–haze days was lower than that after fog–haze days. Proteobacteria alone and Proteobacteria with Firmicutes were respectively detected in 1.5 and 20 m aerosols during fog–haze days. In addition to Proteobacteria and Firmicutes, Bacteroidetes alone and Acidobacteria with Verrucomicrobia were respectively found in aerosols at 20 and 1.5 m after fog–haze days. The fungal species observed during fog–haze days were completely different from those detected after fog–haze days. Ascomycota and Basidiomycota were respectively detected during and after fog–haze days. The distribution of microbial diversity in aerosols exhibited meteorological and site-associated variations. The same potential pathogenic microorganisms were detected at different heights during fog–haze days. This study on the characteristics of microbial population in aerosols could provide a comprehensive understanding of the factors causing the harmful effects of particles on humans during fog–haze days.