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.