Contaminant Source as Factor of Soil Heavy Metal Toxicity and Bioavailabilty to Plants

摘要

Mine waste and sewage sludge treated soil were used as contaminants in a greenhouse pot experiment and the effect of the contaminants on ryegrass growth, soil metal levels and plant metal uptake was evaluated over a period of 16 weeks. Soils were amended with bone meal, compost, peat, coir or lime phosphate and amendments led to immobilization of Pb, Cu and Zn. Biomass yield was significantly reduced in contaminated soil, with greater reduction in mine waste contaminated soil. EDTA extractable soil metal and metal uptake by ryegrass was significantly higher in mine waste contaminated soil than in sewage sludge treated soil.