Soils contaminated with heavy metals are poor in
nutrients and microbial diversity and contribute to suboptimal
plant biomass accumulation as well as impeded
rates of remediation (White et al., 2006). They result from
anthropogenic activities with lack of awareness of health
and environmental effects connected with the production,
use, and disposal of hazardous substances into soil
(Vidali, 2001). The sources of heavy metals in soil arevariable but they mostly arise from mining, smelting, industrial effluents, repeated applications of sewage sludge, municipal wastes and animal slurries, impurities in fertilizers, decomposition of air pollutants by burning of fossil fuels, and various other industrial activities (Wang et al., 2003).