What is Biochar? Biochar is a carbon-rich material produced through the pyrolysis of organic matter, such as agricultural residues, forestry waste, and other biomass. The process involves heating the biomass in a low-oxygen environment, which converts it into a stable form of carbon that can be used to improve soil quality. According to a study published in the journal Nature Communications, biochar can sequester carbon for hundreds to thousands of years, making it a powerful tool in the fight against climate change.