Hydrocarbon Spills on Antarctic Soil

Antarctic exploration and research have led to some significant although localized impacts on the environment. Human impacts Occur around current or past scientific research stations, typically located on ice-free areas that are predominantly soils. Fuel spills, the most common occurrence, have the potential to cause the greatest environmental impact in the Antarctic through accumulation of aliphatic and aromatic compounds. Effective management of hydrocarbon spills is dependent on understanding how they impact soil properties such as moisture, hydrophobicity, soil temperature, and microbial activity. Numbers of hydrocarbon degrading bacteria, typically Rhodococcus, Sphingomonas, and Pseudomonas species for example, may become elevated in contaminated soils, but overall microbial diversity declines. Alternative management practices to the current approach of "dig it up and ship it out" are required but must be based on sound information. This data set summarizes current understanding of the extent and effects of hydrocarbon spillage on Antarctic soils; the observed physical, chemical, and biological responses of such soils; and current gaps in knowledge.
Comparisons between temperature profiles of hydrocarbon contaminated and pristine sites at Scott Base and Marble Point indicate that during sunny weather, when soils are snow-free, the daily maximum surface temperature of hydrocarbon-contaminated soils is often warmer (by up to ca. 10 °C) than adjacent pristine sites The higher temperatures at the hydrocarbon contaminated sites are attributed to decreased soil surface albedo due to surface darkening by hydrocarbons. In contrast, at a Bull Pass site where hydrocarbons 39 contaminated the subsurface, no difference in soil temperature was detected between a pristine and hydrocarbon-contaminated soil. There is potential for hydrocarbons to affect soil moisture regimes. Hydrocarbon-contaminated soils were weakly hydrophobic, whereas no evidence of hydrophobicity was detected at pristine sites. The area affected by hydrocarbons in Antarctica is not large, yet significant hydrocarbon contamination can be detected in soil around current and former scientific research stations more than 30 yr post-spill.