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

VILLALBA PRIMITZ, JULIA; VÁZQUEZ, SUSANA; RUBERTO, LUCAS; LO BALBO, ALFREDO; MAC CORMACK, WALTER

POLAR BIOLOGY

SPRINGER

Año: 2021 vol. 44 p. 289 - 303

0722-4060

Logistics and scientific activities carried out in Antarctic stationsentail the risk of contamination by fuels. Among remediation strategies,biostimulation significantly improves the efficiency of hydrocarbons (HCs)removal. A 1-year-long field trial was performed in mesocosms filled with soil chronicallycontaminated with HCs. Three nutrient sources were evaluated as biostimulationagents: inorganic salts (with and without aeration by mixing), a slow-releasegranular fertilizer (Nitrofoska®) and a commercial bioremediation product (OSEII®). Their performance was assessed considering the number of culturablebacteria, the changes induced in the structure of bacterial communities, the HCs removal efficiencies and the estimation of the abiotic andbiodegradative losses of HCs. The soil indigenous microbiotareduced the concentration of hydrocarbons by up to 50% in 50 days and 87% in365 days depending on the biostimulation agent used. OSEII® (amixture of surfactants, nutrients and enzymes) performed better in the mediumterm, promoting bacterial growth and rapidly inducing changes in the structureof bacterial community, and Nitrofoska® proved to be more efficient forlong-term processes, less affecting the size and structure of the microbiota. Amixed strategy combining the fastest action of commercial products actingduring summer with slow-release fertilizers acting throughout the year isproposed as a long-term bioremediation treatment for Antarctic areas where thetemperature rises above the freezing point and the ground is free of snow shortlyduring summer. This study highlights theimportance of conducting research to develop remediation processes compatiblewith the Antarctic Treaty, exploiting the metabolic potential of the indigenousmicrobiota.