UN Climate Change Conference considers ancient soil replenishment technique in battle against global warming

University of Georgia News: Former inhabitants of the Amazon Basin enriched their fields with charred organic materials-biochar-and transformed one of the earth's most infertile soils into one of the most productive. These early conservationists disappeared 500 years ago, but centuries later, their soil is still rich in organic matter and nutrients. Now, scientists, environmental groups and policymakers forging the next world climate agreement see biochar not only as an important tool for replenishing soils, but as a powerful tool for combating global warming.

Christoph Steiner, a University of Georgia research scientist in the Faculty of Engineering, was a major contributor to the biochar proposal that was submitted by the United Nations Convention to Combat Desertification last week at the United Nations Climate Change Conference meeting in Poland. The new climate change agreement will replace the Kyoto Protocol, which expires in 2012.

"The potential of biochar lies in its ability to sequester-capture and store-huge amounts of carbon while also displacing fossil fuel energy, effectively doubling its carbon impact," said Steiner, a soil scientist whose research in the Amazon Basin originally focused on the use of biochar as a soil amendment. At UGA's Biorefinery and Carbon Cycling Program, he now investigates the global potential of biochar to sequester carbon. He also serves as a consultant to the UNCCD, a sister program to the climate change convention.

Steiner explained that almost any kind of organic material-peanut shells, pine chips and even poultry litter-can be burned in air-tight conditions, a process called pyrolysis. The byproducts are biochar, a highly porous charcoal that helps soil retain nutrients and water, and gases and heat that can be used as energy.

…This unique system ideally utilizes waste biomass, and thus does not compete with food production," said Steiner. Currently most waste biomass decomposes or is burned in the field. Both processes release carbon dioxide stored in the plant biomass-for no other use than getting rid of it. Biochar can capture up to 50 percent of the carbon stored in biomass and establishes a significant carbon sink, as long as renewable resources are used and biochar is used as a soil amendment…

Waste wood at a biomass power plant, shot by Tetris L, Wikimedia Commons, under the terms of the GNU Free Documentation License, Version 1.2