Amazonian Indians used it for centuries to enhance fragile, nutrient-poor tropical soils and provide food for large, socially complex societies. Now momentum's building to use 'biochar,' a modern day form of terra preta, or black earth, as a means of addressing climate change, food and energy security.
The UN Convention to Combat Desertification is pushing to have biochar, and soil enhancement and conservation methods more generally, recognized as valid greenhouse gas abatement technologies eligible for Clean Development Mechanism certified emission reduction credits.
Agricultural, soil and climate scientists and environmental policy experts are getting behind the push to launch 'biochar' programs on a worldwide basis. With 'biochar' campaigning gathering steam UK specialty publishing house Earthscan is about to publish an interdisciplinary biochar research reference and user's guide.
Farmers, Agriculture Hold the Key to Sequestering Carbon
Getting farmers the world over to turn their agricultural waste into charcoal and then burying it is the only way left open to us if world leaders are truly committed to reducing atmospheric CO2, according to James Lovelock, the fiercely independent, outspoken and controversial English scientist best known as the driving force behind the 'Gaia Theory.'
“The biosphere pumps out 550 gigatonnes (billions of metric tons) of carbon yearly; we put in only 30 gigatonnes,” Lovelock explained during an interview published in the Jan. 23 issue of New Scientist. “Ninety-nine per cent of the carbon that is fixed by plants is released back into the atmosphere within a year or so by consumers like bacteria, nematodes and worms.
“What we can do is cheat those consumers by getting farmers to burn their crop waste at very low oxygen levels to turn it into charcoal, which the farmer then ploughs into the field. A little CO2 is released but the bulk of it gets converted to carbon.
“You get a few per cent of biofuel as a by-product of the combustion process, which the farmer can sell. This scheme would need no subsidy: the farmer would make a profit. This is the one thing we can do that will make a difference, but I bet they won't do it.”
Pyrolysis, the technical name for the process Lovelock describes for producing charcoal, is that which Amazon Basin Indians used centuries ago to enhance tropical soils and boost crop production. The process also produces a synthesis, or syngas that can be turned into a liquid fuel or used directly to power a turbine generator.
A Practitioner's Guide to Biochar
Adding to the momentum, Earthscan is readying publication of ''Biochar for Environmental Management: Science and Technology', the first attempt to bring together and synthesize the growing amount of interdisciplinary literature on the subject.
Due out in March, the anthology is edited by Johannes Lehmann, associate professor of soil biogeochemistry and soil fertility management at Cornell University, and Stephen Joseph, a visiting professor at the School of Materials Science and Engineering at the University of New South Wales and vice-chairman of the International Biochar Initiative.
Intended as a practitioner's guidebook as well as policy and scientific research reference, “what is needed in this 21st century of ours, clearly, are solutions that deal with several of our major problems at once. And they must be deliverable quickly, and at a scale able to make a real difference,” writes biochar advocate Tim Flannery in the book's foreword.
“The biochar approach provides a uniquely powerful solution: it allows us to address food security, the fuel crisis and the climate problem, and all in an immensely practical manner...
“Among the most valuable outcomes of the application of the biochar technologies are greatly increased economic efficiency in agriculture, enhanced crop yields, and slowing the return to the atmosphere of carbon captured by plants. The result is diverse and clean energy supplies, more food per unit of input and climate security.”