Abstract
A continuous flow-through system incubated in situ was used to model oil biodegradation in Arctic coastal waters. High numbers of oil-degrading microorganisms were found in the Arctic coastal waters examined in this study. The microbial community underlying oil slicks increased and showed a population shift to a greater percentage of hydrocarbon-utilizing microorganisms. Microbial populations and oil biodegradation were increased by the addition of nitrogen and phosphorus. Both abiotic and biodegradative losses were lower than expected, perhaps due to the unusually harsh, ice-dominated Arctic summer, during which these tests were conducted. Chromatographic and spectrometric analyses showed that residual oils contained similar percentages of individual components and classes of hydrocarbons, regardless of the amount of degradation, indicating that most components of the oil were being degraded at similar rates.