Efficiency of Bacillus and Pseudomonas Bacteria in Bioremediation of a Soil Contaminated with Hydrocarbons

Soil contamination with petroleum compounds since the petroleum exploration in the last century in Iran، and accumulation of these compounds in the environment threaten the health of soil and water resources of the country. The current research was conducted with the purpose of reaching to an efficient approach for the remediation of soils polluted with petroleum compounds. In this research the effect of five experimental treatments including various species of Bacillus and Pseudomonas bacteria with and without barely (Karron cv.) planting on the bio-degradation of those compounds in an artificially polluted loam soil was investigated. Analysis of the data indicated that the maximum purification belonged to the Bacillus 2 treatment. With barely planting this bacteria reduced soil total petroleum hydrocarbons up to %72. 5 during 105 days. Without barely the reduction became %59. 8 at the same period. The rate of bio-degradation was also highest at the same treatment، meaning that during a 20-day the reduction of catumination became %40. Degredation rate considerably increased with the presence of bacteria in the soil comparing to the barely planting alone. Inoculating of contaminated soil with bacteria without the need for particular nursery seems to be enough to control effectively the soil pollution. Among the several examined bacteria، Bacillus 2 turned to be the most suitable one for removing the petroleum- loased contamination.