Phytoextraction of copper and lead from spiked soil using <i>Acalypha wilkesiana</i> (Copper leaf) and <i>Polyscias fruticosa</i> (Aralia)

Abstract

Soil contaminated with heavy metals industrially or anthropogenically is a major global concern. This study aimed at investigating the potential of Acalypha wilkesiana and Polyscias fruticosa plants to remove copper (Cu) and lead (Pb) from soil spiked with solutions of Cu and Pb. Information on the ability of both plants to uptake and accumulate Cu and Pb from spiked soil is insufficient. Plant cuttings were grown in a 2 kg soil spiked with heavy metals and kept at the greenhouse for the period of 240 days. Root, stem and leaf of the plants were analyzed for Cu and Pb using Atomic Absorption Spectrophotometer (AAS). Cu accumulation (2.58 -542.66 mg/kg) was appreciably higher than Pb accumulation (26.24 - 46.44 mg/kg) in A. wilkesiana, while Cu accumulation ranged 4.54 - 384.19 mg/kg was found to be lower than the Pb accumulation ranged 1.22-759.48 mg/kg in P. fruticosa. The maximum accumulation of Cu and Pb in the shoot were found to be 52.50 and 82.93 mg/kg in A. wilkesiana, while 38.26 and 123.98 mg/kg in P. fruticosa. Accumulation of Cu and Pb by both plants were correlated using the indices bioaccumulation, transfer factor and translocation index. The result is encouraging and suggests that both plants could be applied for phytoextraction of Cu and Pb from heavy metal spiked soil.