Introduction of bacteria of the genus Rhodococcus into oil-contaminated tundra soils

The strain Rhodococcus erythropolis E-15, which grows well on hydrocarbons at law positive temperatures, was selected by screening a collection of hydrocarbon-oxidizing bacteria. This strain was introduced into tundra soil contaminated with oil (I kg/m(2)). The natural hydrocarbon-oxidizing microflora of non-polluted tundra soils (isolated on liquid media) accounted for 10(4) cells per g and mainly contained rhodococci. All indigenous rhodococci were of the S-type, with low oxidizing: activity toward hydrocarbons. Fertilizing the soil only slightly increased (by 10%) the rate of hydrocarbon biodegradation by indigenous oil-oxidizing microflora. Five weeks after introduction of the active strain, the soil content of hydrocarbons decreased by approximately 40%. The concentration of the introduced bacterium remained 10(7) cells/g even seven weeks after the beginning of the experiment.