Time factor influence on soil heavy metal concentration in relation to soil contamination assessment

Abstract

: The aim of this study was to investigate the dynamics of changes in the metal concentrations in the soils contaminated with Cd, Pb, and Zn during a 5 year period. Additionally the purpose included assessment of the suitability of 1 M HCl to control soil contamination with heavy metals compared to using of aqua regia method. The study was conducted in concrete-framed microplots, fi lled with two soils (sandy and silty), which were arti fi cially co-contaminated with Cd, Pb and Zn. There was a gradual decrease in these concentrations during the 5 year period. The concentrations of the metals extracted with 1 M HCl were very similar to the total concentrations. After 5 years of research, the topsoil had the smallest decrease in Pb concentration, which for the sandy, and silty soils was, respectively, by 7% and 9% in relation to the initial value.