Role of Biochar in Remediating Heavy Metals in Soil
Heavy metals are persistent pollutants in the environment which contaminate the food chain, pose risk to human health, and intimidate soil quality. Biochar has been proved efficient to reduce the heavy metal toxicity in contaminated soils. In this paper the properties of biochar and its ability to remediate heavy metals, i.e. Pb, Cd, Cr, As, Ni, Zn, and Cu, in soils are elaborated. Biochar application enhances soil fertility, crop yield, plant growth, carbon content, and nutrients availability. The different types of biochar, i.e. chicken manure, green waste, hardwood, oakwood, sewage sludge, rice straw, dairy manure, and cotton, can be applied by various methods for removal of heavy metals. pH is one of the main parameters among many which influence the function of biochar. Although heavy metal contaminated soils can be reclaimed effectively by application of biochar, further research is needed to explore its long term environmental and economic aspect to gain maximum benefits from this novel material.