Bioremediation of hydrocarbon contaminated soil from Carlini Station, Antarctica: effectiveness of different nutrient sources as biostimulation agents

Logistics and scientific activities carried out in Antarctic stations entail the risk of contamination by fuels. Among remediation strategies, biostimulation of chronically contaminated Antarctic soils significantly improves the efficiency of hydrocarbons (HCs) removal. The aim of this study was to evaluate the performance of different nutrient formulations as biostimulation agents, in order to improve the elimination of diesel fuel from Antarctic soils, in both oxic and anoxic conditions. A field test was performed in microcosms (15 kg of soil each) as experimental systems. Each microcosm was prepared by triplicate, sampled every 10 days over a 50-days period and sampled again one year later. Changes in bacterial communities, and qualitative and quantitative HCs analysis were determined. Our results showed that, during the early stages of the process, a multi-component commercial product like OSEII ® (containing nutrients, enzymes and surfactants) determines a rapid elimination of HCs with changes in the structure of the bacterial soil community, whereas a more cost-effective slow-release fertilizer like Nitrofoska ® would be efficient in a long-term bioremediation process.