Microbial population and activity responses to fertilization of petroleum hydrocarbon contaminated soils near Barrow, Alaska

The bioremediation treatment strategy in the Arctic was tested, along with an examination of the effect of fertilization on microbial populations and activity at a pad of coarse sand that once supported fuel storage tanks near Barrow, Alaska. The effect of fertilization on the persistence of aliphatic versus aromatic hydrocarbons was also observed. Results of adding fertilizer showed a decline of soil pH and soil-water potential. The fertilizer significantly increased soil respiration potentials, but not the population of gasoline and diesel degrading microorganisms. Hydrocarbon concentrations were shown to decrease during the experiment, probably due to volatilization of the aromatic hydrocarbons from the surface soil and nutrient-stimulated biotic degradation processes in the subsurface soil. Linear alkanes appeared to have been more strongly affected than branched alkanes; this also suggest the importance of biological processes even at this cold Arctic site. 2 refs