Bioaccumulation of heavy metals by selected plant species from uranium mining dumps in the Sudety Mts., Poland

Concentrations of the heavy metals Cd, Pb, Cu, Ni, Mn, Zn and Fe in soils of uranium-bearing dumps (Sudety Mts. SW Poland, the dumps containing a high proportion of polymetallic minerals), as well as in two tree species (Salix caprea L., Betula pendula Roth.) and a shrub (Rubus idaeus L.), which frequently occur in this area, in spite of being disturbed by mining activities in the past. The accumulation ratio values of heavy metals were calculated. It was revealed that all the species examined, especially the tree species, accumulated high concentrations of heavy metals, above the average values given for plants in literature. R. idaeus generally exhibited the lowest concentrations of heavy metals except Mn, while S. caprea accumulated the highest levels of Cd exhibiting the greatest accumulation capability for this metal within all the examined dumps. There is a potential of using the examined plants in the monitoring of heavy metals in the environment on the basis of a significant correlation between heavy metal content of foliage and soil.