Extractable microbial DNA pool and microbial activity in paleosols of Southern Urals

An evaluation of microbial DNA pools was stract-performed using direct quantitative isolation of DNA from contemporary soils of Southern Urals and paleosols sealed under burial mounds early in the Bronze Age more than 5000 years B.P. Significant regression dependence was found between the biomass and DNA contents in these soils (R-2 = 0.97). Activity and dominant ecological strategies of microbial communities of paleosols and contemporary southern black soil were compared from growth parameters obtained by analysis of respiratory curves. The ratio of maximum specific growth rates of soil microorganisms on glucose and on yeast extract was shown to provide an auxotrophy index for soil microbial communities.