Changes in microbial communities in primary soil and ground under the anthropogenic influence on the territory around Antarctic station "Mirny"

Antarctic station “Mirny” was the first Russian (Soviet) polar station in Antarctica. The anthropogenic impact on the primary ground and soil in the area around of this polar station took place more than 60 years. This is reflected in both the chemical composition of the soil and microbial communities. The article shows multiple increasing of the number of bacteria and microscopic fungi in anthropogenic contaminated soils. Contamination of soil leads to changes of the structure of the microbial community. An increasing proportion of mesophilic bacteria isolates (90%) was shown. The increasing share spores and reduced the proportion of microscopic fungi mycelia were observed. Statistical analysis showed that we have identified almost all of the expected species that live in anthropogenic substrates (42 species), as well as in the control soils (17 species). But we identified only a part of fungal diversity in contaminated soils (32 species). The increase in the number of fungal species in the area of the polar station “Mirny” was proved to be connected with the human activity and introduction of new species. Native species of microscopic fungi were found to be able to colonize new materials previously unavailable to them. They also can be agents of active biodegradation of anthropogenic materials. Among fungal species isolated from anthropogenic contaminated soil and anthropogenic substrates more than 80% can be attributed to opportunistic organisms. Therefore the total number of microorganisms (CFU), the structure of the microbial complexes, the species composition of communities, indicator species, morphology and volume of biomass can be considered as an index of changes in soil microbial complexes and primary soils