Monday, May 22, 2006

carbon sequestration

I've recently learned of 'Terra Preta' - which is a term used to describe the soils of certain sites along the Amazon river that at one point were inhabited by humans who had the practice of 'carbonizing' their waste - this is a very distinct process from burning, it is in fact the very process used to make charcoal today - a low oxygen low temperature burning that reduces the cellulose and other plant chemicals into a pure form of carbon that resists breakdown through biological processes. It has been found that charcoal can remain in soils without breakdown for hundreds to thousands of years thus making it a phenomenal means of sequestering carbon.

But wait, it gets better! The carbon put into the soil actually improves it, allowing a poor soil to retain more water and much much more micronutrients. In fact, while the Amazon itself has very poor soils* the Terra Preta soils of the Amazon are amoung the richest on Earth. Even after hundreds of years of neglet, this amazing soil is taken and sold as potting mix in many parts of South America.

Now it would take a considerable amount of carbon to undo global warming - too much in fact to stop what is happening now, however, over time locking carbon into soil could reduce CO2 in the air by a significant percentage depending on how quickly and with what vigor such technology is taken up. Further we can benefit now by increaing the available farmland in areas that have poor soil. . .Please spread the word about this one, it really could help make a dent in many problems facing us today.

*Most nutrients in the amazon rain forest are locked into the biomass of the trees and once these trees are cut and removed the soils rapidly lose their ability to grow anything!