Community-level physiological profiles of microorganisms inhabiting soil contaminated with heavy metals

The aim of the study was to assess the diffe-rences in the bacterial community physiological profiles in soils contaminated with heavy metals versus soils without metal contaminations. The study’s contaminated soil originated from the surrounding area of the Szopienice non-ferrous metal smelter (Silesia Region, Poland). The control was soil unexposed to heavy metals. Metal concentration was appraised by flame atomic absorption spectrometry, whereas the the community-level physiological profi le was determined with the Biolog EcoPlatesTM system. The soil microbiological activity in both sites was also assessed via dehydrogenase activity. The mean concentrations of metals (Cd and Zn) in contaminated soil samples were in a range from 147.27 to 12265.42 mg kg-1, and the heavy metal contamination brought about a situation where dehydrogenase activity inhibition was observed mostly in the soil surface layers. Our results demonstrated that there is diversity in the physiological profi les of microorganisms inhabiting contaminated and colntrol soils; therefore, for assessment purposes, these were treated as two clusters. Cluster I included colntrol soil samples in which microbial communities utilised most of the available substrates. Cluster II incorporated contaminated soil samples in which a smaller number of the tested substrates was utilised by the contained microorganisms. The physiological profi les of microorganisms inhabiting the contaminated and the colntrol soils are distinctly different.