At the UN climate talks in Poznan, Poland, Cornell University scientist Johannes Lehmann, has advocated using biochar as a means of capturing and storing carbon.
Professor Lehmann explained that the ancient technique of plowing charred plants into the ground to revive soil will also trap greenhouse gases for thousands of years and may forestall global warming. Heating plants, such as farm waste or wood, in airtight conditions produces a high-carbon substance called biochar, which can store the greenhouse gas carbon dioxide and enhance nutrients in the soil.
Professor Lehmann estimated that under ambitious scenarios biochar could store 1 billion tons of carbon annually — equivalent to more than 10 percent of global carbon emissions – for up to a few thousand years. He also cited experiments on 10 farm crops suggesting biochar can also increase yields by up to three times, because the organic matter holds on to nutrients.
See this article for more information about the benefits of biochar.