The recultivation of the soils, contaminated with petrol and diesel fuel, with the help of earthworms Dendrobena veneta and the complex of microorganisms

Abstract

The article investigates bioremediation efficiency of the soil contaminated with petroleum (20 to 60 g/kg) and diesel fuel (20 to 40 g/kg) with the help of earthworms Dendrobena veneta in the presence of bacteria Paenibacillus pabuli, Azotobacter vinelandii, Lactobacillus casei, Clostridium limosum, Cronobacter sakazakii, Rhodotorulla mucilaginosa, Cryptococcus albidus, eria, yeasts Saccharomyces, fungi Aspergillus and Penicillium, as well as Actinomycetales, all being components of biopreparation Baykal-EM. It was demonstrated that in oil-contaminated soil, the content of hydrocarbons decreased by 95 % after 22 weeks in the presence of worms and bacteria. The microbiological preparation introduction increased the earthworms' survivability in oil-contaminated substrate. Microbiological preparation introduction improved the earthworms' survival in contaminated substrate. The microbiological preparation introduction, therefore, allowed to use Dendrobena veneta for soil recultivation with higher oil concentrations that was impossible in the past. In petroleum-contaminated soil the content of hydrocarbons decreased by 97% after 5 months. The presence of the diesel fuel in the amount of 40 g per 1 kg soil had an acute toxic effect and caused the death of 90 % earthworm species in 14 days. Bacteria introduction enhanced the toxic effect of the diesel fuel and resulted in the death of 100 % earthworms after 7 days.