Kiln made biochars: Wood chars to enhance soil fertility
Soil degradation is an acute problem in the managed tropical soils, substantially decreasing crop production and soil ecosystem services. However, soil remediation tools such as biochars, or charcoals used to amend soils, can help overcome limitations commonly constraining tropical systems.
Biochars are recalcitrant forms of pyrogenic carbon produced via pyrolysis, i.e., the thermal degradation of biomass in atmospheres devoid of oxygen. They are porous and have high surface areas with substantial negative charges, properties that can substantially increase soil Cation Exchange Capacity (CEC), and nutrient and water retention. Chars also sorb or otherwise render bioavailability of various phytotoxic soil contaminants.
However, while biochar has been reported to increase the pH of acidic tropical agricultural soils in lab incubations, it is unclear whether liming and base-cation-supply effects persist under field conditions. Nevertheless, the biochar derived here was subsequently applied to agricultural plots and regenerating forests, resulting in much-improved soil fertility.
To read more about the conditions of pyrolysis, the properties of the char, and how it affected soil, please find the open-source published peer-reviewed paper:
https://www.mdpi.com/2571-8789/4/4/69