4. Conclusions
Cavitated charcoal has great potential to deacidify soils and increase the C content. The application of cavitated charcoal does not increase the total content of heavy metals; however, it substantially reduces their mobility. The determined values of the base respiratory activity of the soils into which CHAR-C was introduced were low, which indicates a large number of dormant microorganisms, as confirmed by the values of induced respiratory activity. The obtained results of DhA and Ure activity showed the low metabolic activity of the microbial population in the soils, especially at high rates (7.0% and 14.0%) of CHAR-C. The cavitated charcoal dust used in the study showed high-yielding properties, and its application significantly reduced the heavy metal content in the biomass of Sorghum saccharatum (L.).