• Korean Journal of Microbiology
• /
• v.34 no.3
• /
• pp.101-107
• /
• 1998

Biological treatment of Arabian light crude oil-contaminated pebble was investigated in laboratory microcosms after supplementation with inorganic nutrients and oil-degrading microorganisms. Glass columns ($10cm{\times}20cm$) were used as microcosms and each microcosm was filled with pebbles of diameter less than 40 mm. After initial oil contamination of 2.4% (w/v), Inipol EAP-22 or slow release fertilizer (SRF) was added as inorganic nutrients and microorganisms were sprayed over pebbles. When $C_{17}$/pristane and $C_{18}$/phytane ratios were used as a marker for oil biodegradation, both ratios for microcosm supplemented with SRF and microorganisms were the lowest (below detectable range) after 92 days. Elimination of oil by abiotic processes, however, were minimal with decrease of $C_{17}$/pristane and $C_{18}$/phytane ratios from 3.55 and 2.41 to 3.06 and 1.50, respectively. The numbers of heterotrophic and oil-degrading microorganisms, and biological activity (dehydrogenase activity) corresponded to the course of biodegradation activities in all microcosms. During the whole experimental period, there was no significant nutrient deficiency only in the microcosm with SRF and microorganisms. It seemed that a continuous supply of inorganic nutrients using SRF was the most important factor for the successful performance of biological treatment in oil-contaminated pebbles.