Microbiological and biochemical indicators of lead pollution in soddy-podzolic soil

The effect of lead pollution on the total number of microorganisms, microbial biomass, the number of bacteria of some ecological and systematic groups, and the activity of biochemical processes has been studied. Increasing doses of lead exerted effects of different strength on microbiological and biochemical indicators. Comparative analysis of methods based on their sensitivity to different levels of soil pollution and of the variability of data obtained has shown that the nitrogen-fixation, emission of carbon dioxide, activity of denitrification, dehydrogenase, urease, and the number of free-living and oligotrophic bacteria constitute the most promising indicators for detection of lead pollution. An estimate of the impact of lead on microbiota requires knowledge of the biological properties of nonpolluted soils, along with that of the main physico-chemical parameters, and the content of the pollutant in the studied soil.