Community Structure and Influencing Factors of Airborne Microbial Aerosols over Three Chinese Cities with Contrasting Social-Economic Levels

As an important part of atmospheric aerosol, airborne bacteria have major impacts on human health. However, variations of airborne community structure due to human-induced activities and their possible impact on human health have not been well understood. In this study, we sampled atmospheric microbial aerosols in three Chinese cities (Shanghai, Xiamen, and Zhangzhou) with contrasting social-economic levels and analyzed the bacterial composition using high-throughput sequencing methods. A high similarity of the predominant phyla was observed in three cities but the relative abundances were quite different. At the genus level, the most dominant genus in Shanghai and Xiamen was Deinococcus while the most dominant genus in Zhangzhou was Clostridium. The different characteristics of airborne bacterial in the three cities above may be ascribed to the environmental variables affected by human over-activities such as the vehicle exhausts and coal-burning emissions in Shanghai, the tourist aggregation and construction works in Xiamen, the extensive uses of chemical fertilizers, and agricultural activities in Zhangzhou. The variation of the bacterial community and the pathogenic bacteria detected in three cities would have a potential threat to human health