Fungal community dynamics in a hyper-arid ecosystem after 7 and 47 years of petroleum contamination

This study investigates the impact of crude oil contamination on the fungal community dynamics in the Evrona Nature Reserve, situated in Israel’s hyper-arid Arava Valley. The reserve experienced petroleum-hydrocarbon-spill pollution at two neighboring sites in 1975 and 2014. The initial contamination was left untreated, providing a unique opportunity to compare its effects to those of the second contamination event. In 2022, soil samples were collected from both contaminated areas and nearby clean (control) sites, 47 and 7 years after the spills. The taxonomic diversity of fungal community and functional guilds, as well as various properties of the soil, were analyzed. We focused on three functional groups within fungal communities: saprotrophs, symbiotrophs, and pathotrophs. The results revealed a significant decrease in number of fungal species in the contaminated samples over time. Consequently, prolonged effect of crude oil-contaminated soils can facilitate the development of a distinct fungal community, which has adapted to the conditions of oil contamination. This study aims to elucidate the dynamics of fungal communities in oil-contaminated soils, contributing to a better understanding of their behavior and adaptation in such environments.