Biochar I: What is it?

December 22, 2010 Posted in: ELEMENTS

ELEMENTS” – Biochar I:  What is it? -

Biochar may be the greatest agricultural discovery since Justus von Liebig (1803 – 1883), “the father of the fertilizer industry,” popularized the concept that plant growth was dependent on essential nutrients, including nitrogen and inorganic minerals.  The unique property of biochar is that it is an agricultural catalyst; i.e., it promotes plant growth but is not consumed in the process.  The product is especially effective when mixed with nutrients; the biochar boosts the effectiveness of the fertilizer.  The amazing feature of biochar is that since it is not consumed, it theoretically has to be only applied once, and its effect will continue for generations to come.  While doing so, food growth is promoted, but nutrient mining of the soil is not increased!

The magical properties of biochar do not arise from mysterious, ethereal processes.  The growth promoting properties of biochar originate from its physical, not chemical, properties.  The biochar itself is not consumed as a nutrient for the plant but enhances the effectives of fertilizers and nutrient uptake.  Scientific studies have demonstrated the natural surface area of biocarbon reduces the loss of water-soluble nutrients and fertilizers; thus fertilizer applications can be reduced while maintaining crop output.  Another benefit of biochar is that it acts as a host for soil microbes, which convert minerals in the soil into nutrients for the plants.

The term biochar is a bit unusual in that it does not describe a product but the application of a product.  The pyrolysis or carbonization of biomass produces biocarbon.  The process heats biomass at high temperatures in the absence of oxygen, which converts the renewable material into a coal-like substance (note that coal is not a substitute for biochar).  Biocarbon is synonymous with charcoal, but is utilized in industrial applications whereas charcoal is used residentially for barbeques.  When biocarbon is used in agricultural applications, it is called biochar.