Characteristics of airborne microbial community in Hefei, eastern China, under a good quality in mid-spring

Whether airborne microbial community can be affected by air quality in a short time has been controversial. To study the relationships between the hub bacteria, fungi, and air quality will allow to better understand the mechanism of microbial community change. Total suspended particulate samples were collected to explore the microbial community by metagenome sequencing. Results showed that the bacterial richness and diversity showed a weak uptrend with the increase in air quality index (AQI). The bacterial community was relatively stable, and its minor change was more likely to be caused by AQI. However, the fungal community randomly varied. Only fungal richness showed a weak downtrend with the increase in AQI. Among 14 hub bacteria and 19 hub fungi, four bacteria Marmoricola, Asticcacaulis, Sphingomonas, and Clostridium sensu stricto were related to AQI, but none of hub fungi. In aerosols, there were many pathogenic species (33 bacteria, 17 fungi), and the abundances of pathogens were relatively high (bacteria: > 13.50%, fungi: > 12.08%). The findings presented here indicated that in Hefei in mid-spring, with a good air quality (AQI <= 101), the residents living around the sampling point also may be subjected to health threats by microorganisms.