Persistent petroleum pollution shifts soil microbial responses in Bunger Hills, East Antarctica

Microbes in hyper-arid and oligotrophic ecosystems like Antarctica rely on energy from atmospheric trace gas oxidation to support persistence, primary production, and carbon mitigation. Hydrocarbon contamination is common around Antarctic research stations, yet its implications for these critical ecological processes are unknown. Here, we examined the soil microbial communities of Bunger Hills, East Antarctica, including the impact of a 40-year-old legacy petroleum spill. Metagenomic analysis and gas chromatography revealed significant shifts in microbiome composition and function in contaminated soils, including severely reduced hydrogen oxidation rates, and higher (14CO2) carbon fixation rates. We reconstructed 300 microbial genomes across 16 prokaryotic phyla, describing 24 novel candidate species. Our results demonstrate the long-lasting effects of pollutants on polar microbial ecosystems, highlight the role of trace gas scavengers and hydrocarbon degraders in regulating key ecological functions, and advance our understanding of anthropogenic impacts on microbial nutrient and energy acquisition in dry desert environments. Hydrocarbon-contaminated soils disrupt microbiome composition and function alongside severely reduced hydrogen oxidation rates, and higher carbon fixation rates, according to an assessment of a 40-year-old legacy petroleum spill on the soil microbial diversity of Bunger Hills, East Antarctica.