The dynamic of some biogenic elements content in the soil during remediation of oil contaminated sites

The possibility of bioremediation of territories polluted with oil products in the difficult natural and climatic conditions of the Kola North has been shown. The work has been carried out in the mountain tundra in the north-west of the Murmansk Region. On the site contaminated with diesel fuel 15–20 years ago, the vegetation cover and the organic soil horizon were destroyed. The type of soil on which the research has been carried out is Entic Podzol. During the restoration work, bioremediation methods have been used, and the data about the change of the organic carbon and mobile phosphates content have been obtained. The use of mineral and organic fertilizers increased the carbon of organic humus matter in 1.6–2.1 times and decreased the carbon of petroleum products in 3.3–4.8 times in the soil. At the same time, the fraction of water-soluble carbon of humus decreased in 1.6–2.0 times. The use of fertilizers during bioremediation increased the content of mobile phosphates in 4.3–6.6 times to the values of pure areas. The use of organic fertilizers prevents the leaching of introduced biogenic elements from the sites located on the slopes. The setting of a favorable nutrient condition and decrease of hydrocarbons content have a positive effect on the growth of plants (Festuca pratensis Huds.) in experimental plots. Reducing phytotoxicity of the soil allows for phytorecultivation and the self-overgrowing of plots by native plant species. The results of this study can be used to develop the theoretical basis for improving the efficiency of bioremediation in areas of the Far North, as well as when planning and carrying out work to restore polluted and disturbed areas located on slope