Bioaccumulation of Heavy Metals by Plants in a Closed Industrial Landfill from Bacau, Romania

Abstract

The heavy metals contents of the soils, the botanical characteristics and the level of heavy metal accumulation of a closed industrial discharge were examined. The study should evaluate the levels of heavy metal contamination and accumulative potential of the site's plants and assess the feasibility of remediation by these plant species. The results showed high levels of heavy metals (Cr, Ni, Cu, Zn, As, Cd, Pb) in the soil. The botanical study at the dump showed a plant community rich in biodiversity (20 species and 6 families), with no obvious toxicity symptoms. Measurements of metal levels in dominant species confirmed that they were very similar to those reported for species growing in polluted environments. Metals were found in the leaves and roots of plants found on the landfill. However, the bioconcentration factors are less than 1 except for the case of Carduus australis Pomel in Zn which is 1.04. Positive correlations were noted between heavy metal levels in the leaves. Therefore, for effective site restoration, native species may be well suited to cope with local conditions in a phytoextraction strategy.