Well, silica anyhow. A couple of agricultural scientists from Southern Cross University in Australia figure that particular grass crops, like wheat and sorghum (pictured), can lock away some of those excessive carbon atoms we’re so alarmed about.Apparently microscopic balls of silica, bind to the plant's cells as they draw up minerals up from the soil. They are thought to make the plant stronger while protecting it from disease. Known as phytoliths, or plantstones these silica balls also trap scraps of plant material and thus carbon. And what’s more they are considered near indestructible. So when the plant dies the plantstones find themselves back in the soil locking up carbon for what is believed to be thousands of years.
What the researchers are hoping to unearth is which is which strains of crop are the most effective at this neat trick. To date wheat and sorghum seem to be able to both provide a crop yield and sequester carbon. ::New Scientist, via Sydney Morning Herald