Fungus above us: exploring the atmospheric mycobiome by aircraft

Fungi play a key role in ecosystems, influencing the global bioaerosol budget and pollution dynamics even when metabolically inactive. Despite this, diversity and transport of fungi in the atmosphere are not well explored. This study shows that the atmosphere contains diverse fungi with varied ecological classifications and recruitment patterns reflecting underlying terrestrial habitats. Abundant genera include Neoascochyta , Cladosporium , Alternaria , Coniothyrium , Penicillium , Hymenochaetopsis , Lachnum , and Fonsecazyma . The atmospheric mycobiome is dominated by decomposers and pathogens; over 40% of the sampled airborne fungi are putative plant or animal pathogens. Using aircraft surveys from 2022 to 2023 in distinct seasons alongside comprehensive environmental datasets, airborne fungal diversity was found to decline with altitude and increasing vegetation productivity. Patterns of diversity in atmospheric fungal communities are shaped by vegetation productivity and meteorology. Remote sensing and meteorological data provide valuable insight into this diversity and reinforce the role of local or regional phenology as an important determinant of atmospheric biodiversity. Additionally, the proportional composition of functional guilds in the atmosphere shifts with vegetation productivity and surface winds, suggesting that seasonal transport dynamics may contribute to shaping assembly of the atmospheric mycobiome. This work demonstrates how integrated genomic and environmental datasets acquired by aircraft and satellite data could be leveraged in future to clarify aerobiology questions and contribute to a unified view of fungal ecology.