Soil Amendments to Enhance Lead Uptake by Eucalyptus Camaldeulensis Cultivated on Metal Contaminated Soil

The use of plant to remove heavy metals from soil (phytoremediation) is expanding due to its cost-effectiveness as compared to conventional methods and it has revealed great possible potential. Since contaminants such as Pb have a limited bioavailability in the soil, methods to facilitate their transport to the shoots and roots of plant are required for successful phytoremediation. The objective of this study was to investigate the effects adding of different rates of EDTA at concentrated (0, 5, 10 and 15 mmol/kg), (0, 5, 10, and 25%) of compost, (0, 25, 50, and 100%) of Hoagland solution, bacterial inoculums, and mixtures of 5% EDTA, 5% compost, 100 Hogaland solution, and bacterial inoculums of an amendment on Pb availability in soil, and plant biomass. The phytoextraction ability was assessed in terms of its metal transfer factors; bioconcentration factor (BF) and translocation factor (TF). Experimental results showed that the higher concentrations of available Pb (12.6 ± 0.47, 17.6 ± 0.68, 13.1 ± 0.27, 15.4 ± 0.66, and 17.2 ± 0.98 mg kg-1) were obtained from soil amended with 25% compost, 15 mmol EDTA, 100% Hoagland solution, Bacterial inoculums, and mixed amendments (5% composite, 5 mmol EDTA, 100% Hoagland solution and bacterial inoculums), respectively. Application of mixed amendments increased the fresh and dry weights of shoot and root of E. camaldeulensis cultivated on Pb contaminated soil. The highest accumulation of Pb (585±4.5 and 1073±7.6 mg kg-1DW) in plant shoot and root, respectively, were obtained by plant cultivated in soil inoculated with Alcaligenes eutrophus. Based on the BCF and TF values, E. camaldeulensis can be utilized as a good candidate for Pb stabilization in soil. Keywords: Phytoremediation, Pb-uptake, E. camaldeulensis