Mobility and extraction potential of lead from impacted rifle range soil using Pisum sativum and Brassica juncea

In this study, eight terrestrial plant species ( Brassica juncea, Pisum sativum, two native species (Equisetum arvense, Phragmites australis) and four Pelargonium species) were screened for their potential to remediate a sandy-clay rifle range soil, where lead (Pb) was the contaminant of concern (x¯ = 1018 mg/kg). Enhanced mobilization and uptake of lead was attempted through the application of natural (hemlock mulch and spent grain) and synthetic chelators (ethylenediaminetetraacetic acid (EDTA)). The results of initial screening experiments identified B. juncea and P. sativum as candidates for further study and identified EDTA as the most effective lead-mobilizing agent. Subsequent experiments focused on the extraction potential of B. juncea and P. sativum under increased chelate (EDTA) applications and under sulphur-induced soil acidification. Greenhouse experiments were also conducted to complement the field experiments.; Overall results suggest that P. sativum is more effective phytoremediation tool for the rifle range soil than B. juncea, and also that soil acidification has the potential to be as effective as low dose applications of EDTA in enhancing lead extraction. However, EDTA was still most effective in enhancing lead concentrations in shoot tissues. (Abstract shortened by UMI.)...