image credit PNNL – Pacific Northwest National Laboratory (Flickr CC)

Biochar is charcoal produced from burning biomass – basically, any plant or animal waste – in very low oxygen conditions. Pre Colombian Amazonian cultures did this by smoldering agricultural waste in soil pits and then using the resultant biochar for fuel and fertilizer.

When biochar is produced it captures carbon rather than releasing it into the atmosphere. It therefore has great potential as a way of revolutionizing the way we dispose of waste.

Researchers at Cornell University have estimated that if biochar technology were applied to waste management all around the world it could reduce global carbon emissions by 1.8 gigatons – about 12% per year.

From a BBC News Earth Watch article:

The researchers identify six ways in which biochar curbs emissions, including reducing methane production from decaying plant waste, reducing nitrous oxide release from soils, and avoiding carbon dioxide emissions by storing carbon in the soil.

Because it also fertilizes soil, biochar is potentially great for food production as well as waste management and climate change mitigation. But if it is produced as a product, rather than a waste bi-product, it could do more harm than good. There are also important differences in the benefits/risks of biochar produced from different sources.

It seems fitting, however, that a simple product, so beneficial for soil health, plant growth – and potentially climate change mitigation – should come from the ancient cultures of the Amazon.

For more on biochar see the following piece from the New York Times:

Once-Lowly Charcoal Emerges as ‘Major Tool’ for Curbing Carbon