Ph.D. - McGill University
Many soil microbes can degrade petroleum, since they are adapted to metabolizing complex carbon compounds, such as those found in soil organic matter. This creates the potential for competition within the contaminated soil microbiome, just as we would be likely to find in most "pristine" microbial habitats. The focus of my Ph.D. work was the bioremediation of Arctic soils that have been contaminated by petroleum hydrocarbons. Human activity in any environment carries a risk of contamination, but the remote Arctic is increasingly vulnerable as its oil reserves become more accessible, and nations intensify their efforts to exploit this resource. Microorganisms that are indigenous to Arctic soils are well-adapted to cold and sometimes nutrient-poor conditions, but some environmental modifications may be needed to optimize microbial bioremediation potential. For instance, nitrogen-based fertilizers are frequently added to hydrocarbon-contaminated soils, since they can allow increased microbial growth when carbon is in abundance and nitrogen is limiting. But not all hydrocarbon degraders are created equal. So which microorganisms benefit from this added nitrogen? What other factors might affect community composition in a contaminated soil? And are we promoting the most efficient hydrocarbon-degrading communities? |