The stability of biochar in the environment

Abstract

Pyrogenic organic matter (OM) is a carbon-rich material that is present in a variety of forms ranging from lightly charred biomass to charcoal to soot (Masiello 2004). It is known as ‘black carbon’ (BC) by geochemists and has come to be referred to as ‘biochar’ when created by pyrolysis in oxygen-limited conditions. An understanding of the effects of biochar amendment on soil nutrient cycling, water balance, ecology, soil fertility and other associated beneficial properties is still emerging. However, it has long been clear that biochar, as a relatively refractory form of OM, can be used as a carbon (C) sequestration tool. That is, biomass C in its pyrogenic form is less susceptible to remineralization (i.e., conversion back to CO2 and perhaps CH4) in the environment than its non-pyrogenic form.