Plant Species Identification for Phytoremediation of Mixed Contaminated Soils

This study describes pot experiments that were conducted to investigate the plant species considered suitable for phytoremediation of mixed contaminated soil. Mixed contaminated soil was prepared by spiking silty clay soil with organic contaminants (naphthalene and phenanthrene) and heavy-metal contaminants (lead, cadmium, and chromium). Twelve species of plants were grown in pots filled with contaminated soil. Plants grown in uncontaminated soil were used as control. Results showed that five plant species (sunflower, oat plant, rye grass, tall fescue, and green gram) were able to survive the mixed contaminated conditions. The oat plant had better growth characteristics and minimal stress signs in mixed contaminated soil than the other species. Even though sunflower plants did not show the best growth characteristics, the maximum contamination removal from the soil was achieved by these plants. Exchangeable heavy metals were also reduced in the soil that was planted with sunflower plants compared with contaminated unplanted soil. (C) 2015 American Society of Civil Engineers.