Biochar

This article may require copy editing for cohesion. You can assist by editing it. (May 2024) (Learn how and when to remove this message)

Biochar is the lightweight black residue, consisting of carbon and ashes, remaining after the pyrolysis of biomass, and is a form of charcoal.^[1] Biochar is defined by the International Biochar Initiative as the "solid material obtained from the thermochemical conversion of biomass in an oxygen-limited environment".^[2]

Biochar is mainly used for soil application and is known to improve soil nutrient availability, aeration in soil, and soil water filtration.^{[not verified in body]} Biochar application may thus increase soil fertility of acidic soils and increase agricultural productivity.^{[3][better source needed]} Potential adverse effects of biochar include the disturbance of soil pH levels and the introduction of harmful chemical characteristics that cause problems at the micro dimension.^{[not verified in body]}

Beyond soil application, biochar can be used for slash-and-char farming, for water retention in soil, and as an additive for animal fodder. There is an increasing focus on the potential role of biochar application in global climate change mitigation. Due to its refractory stability, biochar can stay in soils or other environments for thousands of years.^[4] This has given rise to the concept of Biochar Carbon Removal, i.e. carbon sequestration in the form of biochar.^[4] Carbon removal can be achieved when high-quality biochar is applied to soils, or added as a substitute material to construction materials such as concrete and tar.