Phytoremediation of heavy metal contaminated soil using different plant species

Abstract

A pot experiment was conducted to compare the plant biomass accumulation and heavy metal (HM) uptake by plant species grown in HM contaminated soils. The shoot dry weights of Eucalyptus camaldeulensis, Medicago sativum, and Brassica juncea grown in contaminated soils were reduced by 8, 5, and 3-fold, respectively, compared to the same plants grown in control soil. The Pb concentration in the shoots of M. sativum, E. camaldeulensis and B. juncea grown in contaminated soil was 8.7, 11.0, and 8.8-fold, respectively, higher than Pb concentration in plants grown in control soils. M. sativum and E. camaldeulensis accumulated higher Zn concentrations in roots (71 and 86 mg kg^-1) and shoots (49 and 47 mg kg^-1), respectively. Zn concentrations in the roots of M. sativum, E. camaldeulensis and B. juncea were higher than in the shoots by a factor of 1.4, 1.8, and 1.3-fold, respectively. The highest Cu concentration (81 and 37 mg kg^-1 dwt) was obtained in root and shoot of M. sativum grown in contaminated soil, while the highest Cr concentration (133.9 mg/kg dwt) was determined in the root of E. camaldeulensis. This suggests that E. camaldeulensis was the best candidate species for phytoremediation of HM contaminated soils.

Keywords: Phytoextraction, Roadside soil, Heavy metal, Brassica juncea, Medicago sativum, Eucalyptus camaldeulensis