PHYTOSTABILIZATION OF A PB-CONTAMINATED MINE TAILING BY VARIOUS TREE SPECIES IN POT AND FIELD TRIAL EXPERIMENTS

Abstract

The potential of 6 tree species (Leucaena leucocephala, Acacia mangium, Peltophorum pterocarpum, Pterocarpus macrocarpus, Lagerstroemia floribunda, Eucalyptus camaldulensis) for phytoremediation of Pb in sand tailings (total Pb >9850 mg kg⁻¹) from KEMCO Pb mine in Kanchanaburi province, Thailand, were investigated employing a pot experiment (3 months) and field trial experiment (12 months). In pot study E. camaldulensis treated with Osmocote fertilizer attained the highest total biomass (15.3 g plant⁻¹) followed by P. pterocarpum (12.6 g plant⁻¹) and A. mangium (10.8 g plant⁻¹) both treated with cow manure. Cow manure application resulted in the highest root Pb accumulation (>10000 mg kg⁻¹) in L. floribunda and P. macrocarpus. These two species also exhibited the highest Pb uptake (85-88 mg plant⁻¹). Results from field trial also showed that Osmocote promoted the best growth performance in E. camaldulensis (biomass 385.7 g plant⁻¹, height 141.7 cm) followed by A. mangium (biomass 215.9 g plant⁻¹, height 102.7 cm), and they also exhibited the highest Pb uptake (600-800 μg plant⁻¹). A. mangium with the addition of organic fertilizer was the best option for phytostabilization of Pb-contaminated mine tailing because it retained higher Pb concentration in the roots.

KEY WORDS::

• phytostabilization
• tree species
• Pb
• sand tailing
• pot experiment
• field trial experiment

ACKNOWLEDGMENTS

This research work was supported by the grants from the Office of Commission on Higher Education; Post-graduate Education, the Centre on Environmental Health, Toxicology and Management of Toxic Chemicals under Science & Technology Postgraduate Education and Research Development Office (PERDO) of the Ministry of Education; and Mahidol University, Bangkok, Thailand. We are grateful to Assist. Prof. Philip Round for editing the manuscript.