Changes in hydrocarbons content and bacterial community structure in biopiles containing contaminated Antarctic soil amended with different nutrient sources.

Buenos Aires

Conferencia; XXXI SCAR (Scientific Committee on Antarctic Research) and Open Science Conference.; 2010

Human activities in Antarctic Regions are the main source of soil pollution. Nowadays, bioremediation has emerged as a cost-effective and environmentally friendly tool to eliminate in situ hydrocarbons from contaminated soils. As biostimulation seems to be the best strategy for remediation of chronically contaminated soils, selection of the most efficient nutrients is crucial. Also the presence of surface-active compounds showed to enhance the hydrocarbon removal. The objective of this study was to evaluate the effect of different nutrients sources and the presence of a surfactant (Brij®700) on the bioremediation of chronically hydrocarbon-contaminated soils from Jubany Station, Antarctica. Inorganic salts (NSSB); fish meal (FMB) and a commercial fertilizer (NPKB) were tested in the presence of Brij®700 using on site biopiles. Control systems with and without surfactant (CC and CCB) were included. Hydrocarbon-degrading bacterial counts (HDB), total hydrocarbons (TPH) and dehydrogenase activity (DA) were evaluated. Also, PCR-DGGE profiles were made to investigate changes in soil bacterial community structure. Only FMB showed increased HDBand DA levels compared with CC. Final TPH values in fertilized systems did not exhibit significant differences compared with CC except FMB that showed a removal efficiency of 30 %. DGGE profiles showed that the presence of surfactant cause a significant shift in the bacterial community composition which was not encompassed with a greater degradative efficiency. Fish meal, that also caused an evident change in bacterial community composition, significantly increased hydrocarbon removal compared with the other systems. However, the removal efficiency of FMB only reached 30%.