Environmental Assessment of Contaminated Permafrost Soils and Development of Bioremediation Methods

Abstract

The article presents the ecological assessment of contaminated soils. Residual oil pollution significantly affects the structure of microbiocenoses of permafrost sod-steppe, meadow-sod-loamy, sod-humus-bog soils. Strains of indigenous bacteria Bacillus subtilis possess a strong hydrocarbon, emulsifying and antifungal, and moderate growth stimulating properties; can form the basis of biological products for the restoration of oil contaminated permafrost soils. As the data show, emulsifying index is 55 to 85%; therefore the studied liquid cultural strains of bacteria of the genus Bacillus, isolated from permafrost soils and paleomicroflora possess emulsifying properties. As a result of studying the oxidizing properties of the strains of bacteria Bacillus subtilis Kolyma - 7/2k and Bacillus subtilisOimyakon - 6/1 had been certified and deposited in the Russian National Collection of non-pathogenic microorganisms for agricultural purposes as promising for the recovery of oil contaminated permafrost soils under the registration numbers "CIAM 167" and "CIAM 168" in the group of spore-forming microorganisms (All-Russian Research Institute of Agricultural Microbiology  reference number 616/12 and number 617/12 from 20.12.2009). For the first time it was offered a biological method of oil contaminated permafrost soils recovering. Scientific novelty of the development is confirmed by Russian patent "Method of cleaning permafrost soils from oil spore-forming bacteria Bacillus subtilis" (№2446900, priority of invention, 13.07.2010, registered in the State Register of Inventions of the Russian Federation 10.04.2012). Presented results of research to find ways of bioremediation of oil contaminated soils can be used as an effective and environmentally friendly method of recovery of northern ecosystems.