As James Lovelock noted, if we want to end the excess of carbon in our atmosphere, we have an easy way in biochar. Partially burn vegetation (and/or people) in a low-oxygen environment and you produce slow-decaying organic junk that you can bury and thus trap carbon.
Biochar is a fine-grained charcoal high in organic carbon and largely resistant to decomposition. It is produced from pyrolysis of plant and waste feedstocks. As a soil amendment, biochar creates a recalcitrant soil carbon pool that is carbon-negative, serving as a net withdrawal of atmospheric carbon dioxide stored in highly recalcitrant soil carbon stocks. The enhanced nutrient retention capacity of biochar-amended soil not only reduces the total fertilizer requirements but also the climate and environmental impact of croplands. Char-amended soils have shown 50 – 80 percent reductions in nitrous oxide emissions and reduced runoff of phosphorus into surface waters and leaching of nitrogen into groundwater. As a soil amendment, biochar significantly increases the efficiency of and reduces the need for traditional chemical fertilizers, while greatly enhancing crop yields. Renewable oils and gases co-produced in the pyrolysis process can be used as fuel or fuel feedstocks. Biochar thus offers promise for its soil productivity and climate benefits.
As a soil amendment, char can sequester or store the carbon in the soil for hundreds and even thousands of years in the stable char matrix. Equally important, the char improves soil fertility, thereby stimulating plant growth, which then consumes more CO2 from the atmosphere. The bio-energy produced as part of the process can be turned into electricity, process heat, ethanol, methanol, or soon, an ultra-clean liquid diesel fuel. The net amount of CO2 in the atmosphere from both these products is thus reduced, making the bio-char process carbon negative and also regenerating soil fertility in the process.
We love the char. It’s a constructive, decentralized solution we could implement tomorrow.
Healthy soil is full of life, with entire communities living just below our feet. Healthy soil can retain and purify water, provide an abundance of food, and even act as way to sequester carbon dioxide. One key to getting there is amending soil with biochar. Biochar is what you get when biomass is heated in the absence of oxygen through a process called pyrolysis. When incorporated into soil, biochar provides the structural habitat needed for a rich community of micro-organisms to take hold. Incorporating biochar into soil can also act as a way to sequester carbon.
Carbon dioxide sequestration was not likely the original goal of biochar, or terra preta, developed thousands of years ago by the Native Americans in the Amazon region. But today, as we recognize the cost of emitting green house gases, we also recognize the wisdom of using biochar as micro-habitat to improve our soils. Biochar is a classic win-win scenario, a solution that can provide us with a valuable tool for fighting climate change, world hunger, poverty, and energy shortages all at the same time.
But of course — as with all human things — we have political problems motivating each other, so we won’t do it.