Severe East Asian dust storms occur in spring due to dust-emitting winds in the Gobi Desert associated with Mongolian cyclones. The present study performs the first quantitative assessment of the contributions of Mongolian cyclones to springtime dust activity in East Asia, based on multiple reanalyses and observational datasets for 2001–2022. Atmospheric depressions dominate dust activities in Northern China, explaining ~90–92% of the total dust emissions in the Gobi Desert and ~88–93% of the dust aerosol optical depth (τ) downwind, depending on the dataset. Mongolian cyclones, defined as long-living and mobile atmospheric depressions, explain almost half (~34–47%) of the Gobi’s total dust emissions and τ downwind, and are the primary driver of high-impact dust storms. The number of Mongolian cyclones, along with the dust activity, has decreased since 2001, with a spatial pattern of the dust emission trend that is consistent with the northward shift of cyclone tracks.

Recently, serious haze pollution events have frequently occurred in many areas of China, but research on other environments, such as the mountains, remains very limited. In this study, airborne microbial samples from Qinling Mountain (34.03° N, 109.02° E, and 969 m above sea level) were collected during a haze pollution event that occurred on January 2017. Plate count method and high-throughput sequencing technology were used to detect the airborne bacteria. Results showed that the mean concentration of airborne culturable bacteria in Qinling Mountain was 3788 ± 1807 CFU m⁻³, which was higher than the surrounding city, and most of the bacteria were associated with coarse particles (76.9%–84.9%). The coarser particulate matter (PMs) had higher bacterial diversity and abundance than fine PMs. The community structures of airborne bacteria in PMs of different sizes were similar. Source tracking analysis indicated that a small portion of the airborne bacteria could have been from the surrounding environment, while most came from the neighbor cities or other areas that may have aggregated by long-range air masses transport. The results of this work provide an important reference for mountain environmental science and also improved our understanding of the relationship between air pollution and human health.