The intensification of agricultural production on a global scale has become the need of hour to fulfill the food supply of increasing world population. As a result, more and more organic carbon is being removed from the soil leading to dramatic soil degradation. Over-exploitation of soils has depleted an enormous amount of soil organic carbon.
One method of increasing the soil health is through the application of biochar (carbonized material) that have long term stability. The term biochar refers to black carbon formed by the pyrolysis of biomass i.e. by heating the biomass in an oxygen-free or low oxygen environment such that it does not combust. The definition adopted by International Biochar Initiative (IBI) further emphasizes on its application on agricultural lands. The charred material has highly porous structure, potentially responsible for improved water retention and increased soil surface area.
The study of physical and chemical properties of biochar has led to the conclusion that it may serve as a long term source of organic carbon, reduce leaching of organic and inorganic fertilizers and has potential to increase the soil productivity. It also increases the water holding capacity of soil and its nutrient use efficiency. Although some evidences exist that it can reduce the soil emissions of N2O and CH4. Therefore, it may help in climate change mitigation. Further studies in this field may help in better understanding of its interaction with soil.