Biochar is produced by thermal decomposition of biomass under oxygen-limited conditions (pyrolysis), and it has
received attention in soil remediation and waste disposal in recent years. The characteristics of biochar are influenced
mainly by the preparation temperature and biomass. Higher pyrolysis temperature often results in the increased surface
area and carbonized fraction of biochar leading to high sorption capability for pollutants. Biochars derived from various
source materials show different properties of surface area, porosity and the amount of functional groups which are
important concerning on the effect of biochar. Biochar has been proved to be effective in improving soil properties and
increasing crop biomass. It has also been suggested that it can even enhance crop resistance to disease. Biochar has
recently been used to remediate soil with both heavy metal and organic pollutants. The mechanism is electrostatic
interaction and precipitation in the case of heavy metal, and the surface adsorption, partition and sequestration in the
case of organic contaminants. However, application of biochar in soil has been shown to result in decreased efficacy of
pesticides, which indicates a trade-off between the potentially promising effect of biochar on pesticide remediation and
its negative effect on pesticide efficacy. While arguments on the effectiveness of biochar appear sound, further research
is needed prior to widespread application of biochar in soil remediation.