Utilization and supplementation of phytoextraction potential of some terrestrial plants in metal- contaminated soils

Abstract

Urban soils are increasingly acting as a sink for a wide range of contaminants including heavy metals due to the rapid pace of development. Zn, Co, Cd, Pb, Cr, Ni, Cu, and As content of soils was quantified in a semiarid urban industrial zone in India. Metal accumulation in flora on site was also evaluated for prospects of phytoremediation. Accumulation of individual metals in soils as well as their uptake and translocation in plants differed. Calotropis procera, Chenopodium murale, and Poa annua were selected to validate their phytoremedial potential at different concentrations of Pb, Cd, and Cu. Possible enhancement of phytoextraction/phytostabilization through soil amendments was also explored. P. annua (for Pb and Cu) and C. murale (for Cd) were categorized as phytoextractors, while C. procera was categorized as a phytostabilizer of Cd. Manure, EDTA, and mycorrhizae were used as amendments, and metal accumulation trends were plant/metal specific in response to all amendments except EDTA, which enhanced metal uptake in all test species.