Seasonal taxonomic composition of microbial communal shaping the bioaerosols milieu of the urban city of Lanzhou.

Here, the taxonomical composition and seasonal dynamics of airborne microbial communities were described in the urban city of Lanzhou, Northwest China. Year-long samples were studied in two filter membranes (Quartz and PTFE). Higher microbial loads were reported in the PTFE than in the quartz filter. Onefold decrease was reported in bacterial loads in spring and summer than winter and autumn for both filters. The fungal loadings were lowest during winter and highest during autumn, followed by summer. The microbial communities included Actinobacteria and Proteobacteria, Ascomycota, and Basidiomycota as major components. Maximum abundance of the members from Gammaproteobacteria, Coriobacteria and Clostridia were studied in all seasons on PTFE membrane, followed by, Erysipelotrichia, Negativicutes and Fusobacteria. Members of Actinobacteria and Bacilli showed higher abundance in spring and winter, with a small proportion during autumn. Members of Clostridia, Gammaproteobacteria, Bacilli, and Actinobacteria showed maximum abundance on the quartz filter in all the seasons. Similarly, on the PTFE, fungi including Dothideomycetes and Agaricomycetes were dominant, followed by Saccharomycetes during summer and winter. The result showed that PM2.5, SO42-, NO2-, Na+, EC, and OC are important environmental parameters influencing the seasonal microbial community. However, the relation of the microbiome with the environment cannot be confidently defined because the environmental factors are changeable and yet interrelated.