20.500.12556/RUL-143801 Dissecting giant hailstones a glimpse into the troposphere with its diverse bacterial communities and fibrous microplastics The formation of giant hailstones is a rare weather event that has devastating consequences in inhabited areas. This hazard has been occurring more frequently and with greater size of hailstones in recent years, and thus needs to be better understood. While the generally accepted mechanism is thought to be a process similar to the formation of smaller hailstones but with exceptional duration and stronger updrafts, recent evidence suggests that biotic and abiotic factors also influence the growth of these unusually large ice chunks. In this study, we improved these findings by determining the distribution of a wide variety of these factors throughout the hail volume and expanding the search to include new particles that are common in the environment and are of anthropogenic origin. We melted the concentric layers of several giant hailstones that fell to the ground over a small region in Slovenia in 2019. The samples, up to 13 cm in diameter, were analyzed for biotic and abiotic constituents that could have influenced their formation. Using 16S rRNA-based metagenomics approaches, we identified a highly diverse bacterial community, and by using scanning electron microscopy and Raman spectroscopy, we found natural and synthetic fibers concentrated in the cores of the giant hailstones. For the first time, we were able to detect the existence of microplastic fibers in giant hailstones and determine the changes in the distribution of sand within the volume of the samples. Our results suggest that changes in the composition of hail layers and their great diversity are important factors that should be considered in research. It also appears that anthropogenic microfiber pollutants were a significant factor in the formation of the giant hailstones analyzed in this study. hailstone microplastics environmental pollution metagenome analysis atmospheric microbiology true false true Angleški jezik Ni določen Članek v reviji 2023-01-12 11:35:35 2023-01-12 11:35:35 2023-01-13 04:03:48 0000-00-00 00:00:00 2023 0 0 8 str. pt. 1, art. 158786 Vol. 856 2023 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 502/504 0048-9697 10.1016/j.scitotenv.2022.158786 122212099 1-s2.0-S0048969722058855-main.pdf 1-s2.0-S0048969722058855-main.pdf 1 50EC7295DEAF0B3A51F9696207AC1996 cb9989747d865d96052d87c88151f466d78cdad6a73c7cd58bf98a946be1d977 dd2e37ba-9264-11ed-9c94-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=165743 https://www.sciencedirect.com/science/article/pii/S0048969722058855 0 bc5d9c83-9264-11ed-9c94-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=165742 Fakulteta za kemijo in kemijsko tehnologijo Biotehniška fakulteta 0 0 0