Response of Microbial Activities to Additional Metal Amendment to Long-Term Heavy Metal Contaminated Soils

摘要

Smelters and mines are of the greatest and often the oldest industrial sources of soil heavy metal contamination. Negative effects of heavy metals on microbial communities and activities have been many times reported (i.e. Brookes, 1995; Giller et al,1998; Paton et al., 2006). On the other hand, microbial functions in soils are typically quite resilient towards toxic effects of metals and are often found to recover after an initial inhibition by high metal inputs (Holtan-Hartwig et al., 2002). Development of tolerance towards heavy metals by microbial communities is a commonly known fact (Gadd, 1992) which may have various explanations, such as long term genetic modifications, spread of resistance genes among microorganisms or replacement of metalsensitive strains by tolerant strains. The aim of this research was to evaluate the ability of the soil microbial communities in a long-term contaminated soil to tolerate the additional Cd and Pb treatment.