Potential for bioremediation of hydrocarbon polluted soils in the Maritime Antarctic

Abstract

Human activity in the Antarctic requires the use of petroleum hydrocarbons as the main energy source for a variety of operations. In the current study, in situ soil microcosms were constructed in the proximity of the Brazilian Antarctic Station Comandante Ferraz, King George Island, South Shetland Islands, to analyse the effect of oil amendment on the indigenous bacterial community in contaminated and uncontaminated sites to assess the potential for bioremediation. Microcosms were sampled for heterotrophic and hydrocarbon-degrader bacterial counts, pH, temperature, moisture, nutrient levels and petroleum hydrocarbons. Total organic carbon, nitrogen and phosphorus contents were generally low in the Antarctic cryosols. According to statistical analysis based on Colony Forming Unit numbers, significant bacterial populations were present in all microcosms, with larger numbers observed in oil amended than in non-amended soils. Aliphatic and aromatic fractions of diesel fuel were detected in the soil microcosms, and significant quantities were removed during the experiment. These results strongly suggest that the cold-adapted bacterial community present in soils around the Brazilian Antarctic station has the potential to adapt and utilize the oil as a carbon source. This knowledge can contribute both to bioremediation technology and the goals of the the Antarctic Treaty which prohibits the introduction of foreign organisms into the region.