Biodegradation of Aliphatic and Aromatic Fractions of Heavy Crude Oil-Contaminated Soil: A Pilot Study

Crude oil is one of the major contaminants of soil and water. Biodegradation is a good option for reducing oil contamination in soil. Soil fertilizers can help the microorganisms biodegrade oil with higher efficiency. In this study, the effect of chemical fertilizers and animal manure on crude oil reduction was compared and the reduction of the aliphatic and aromatic fractions was studied during 8 months. The higher reduction of crude oil (54%) was observed in tests containing chemical fertilizers and wood chips, followed by those containing animal manure (46%). The reduction of aliphatic and aromatic fractions was also higher in fertilized tests. Our results showed that in the experiments with mixed chemical fertilizers and wood chips, the reduction of crude oil and its aliphatic and aromatic fractions was higher than the experiments with only chemical fertilizers and those with animal manure. The reductions in the experiments with animal manure, however, were higher than those with only chemical fertilizers.