Airborne bacterial communities over the Tibetan and Mongolian Plateaus: variations and their possible sources

Abstract

The transportation of atmospheric bacteria is increasingly recognized as an important factor that affects bacterial diversity in natural environments as well as human health. However, few studies have investigated airborne bacterial biodiversity in extremely remote, arid, and cold environments, such as desert and alpine areas, which may contain ambient bacteria transported by air masses. In this study, atmospheric aerosol samples were collected from the southern slope of the Himalayas, the southern Tibetan Plateau and the Mongolian Plateau to analyze the diversity of airborne bacteria and its relationship to environmental factors. The results show that the bacterial communities in all samples were predominantly composed of Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes. Furthermore, the community structures of airborne bacteria exhibited significant differences among the collected sample, these differences mainly depended on meteorological parameters (P values < 0.01). In particular, the aerosol samples over the Tibetan Plateau showed the lowest diversity among the three regions. This suggests that the variability in airborne bacterial communities is determined by meteorological parameters and long-range transportation. Our study provides new information about airborne bacterial community composition in extreme environments and its large-scale spatial variability.