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Scientists Promote Benefits of Black Magic Soil

Brian | 24.02.2006 23:17

Some good news for a change. This story was reported on by BBC Horizon a few years ago. It is one of a number of ways to improve agriculture without going the way of toxic chemical science or GM.
It also shows us that the ancients new some things the moderns no nothing of, and the benefits of traditional knowledge and praxis.

Scientists Promote Benefits of Black Magic Soil
By Corey Binns
Special to LiveScience
posted: 22 February 2006
11:14 am ET
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ST LOUIS—Black soil created by humans long ago could brighten the future of modern farming and help curb global warming.

The dark earth, called terra preta, was produced by Amazonian people who slowly burned their waste by smoldering it, thousands of years ago.

Archaeologists from the University of Sao Paulo in Brazil believe this soil was never used or intended for farming purposes by early Amazonian populations, but scientists have found it to be highly fertile. Today, Amazonian farmers reap the benefits of this carbon-rich soil.

"These indigenous people were not farmers. The potential has just been lying in the soil waiting for modern farmers to discover it," archaeologist Eduardo Goes Neves told LiveScience.

Amazing properties

Scientists say terra preta can do much more than a box of Miracle-Gro. The process of making it pulls carbon out of the atmosphere, and can reduce global warming.

"The knowledge we can gain from studying the Amazonian dark earths, found throughout the Amazon River region, not only teaches us how to restore degraded soils, triple crop yields and support a wide array of crops in regions with agriculturally poor soils, but also can lead to technologies to sequester carbon in soil and prevent critical changes in world climate," said Johannes Lehmann, a biogeochemist at Cornell University.

Lehmann and Neves reported their findings here last week at the annual meeting of the American Association for the Advancement of Science.

The remaining terra preta resources are in high demand by local Brazilian farmers who use it to boost crop production.

With Brazil's population close to 200 million, and limited amounts of terra preta, scientists are concerned that farmers will quickly exhaust the reserves and harm precious archaeological sites in the process.

Concocting new terra preta and replicating the ancient practice of smoldering waste could bring sky-high benefits.

Slash-and-char

The smoldering method of burning waste called slash-and-char—similar to the process used by ancient Amazonians—reduces greenhouse gases by capturing carbon from the air and storing it in the ground. It also cuts down methane and nitrous oxide emissions from soils.

Alternatively, in most parts of the world, farmers use slash-and-burn methods to prepare fields and crops, which release greenhouse gases. Adopting a slash-and-char approach could result in a 12 percent reduction in carbon emissions by humans, Lehmann said.

To curb the archaeological destruction in Brazil and improve agriculture production worldwide, researchers have come up with a modern method of creating this black magic earth.

Take some normal soil, add a handful of charcoal, a bunch of leaves and a dollop of cow poop.

You've got modern-day terra preta, called bio-char.

"Bio-char has these very efficient properties of retaining nutrients. It will retain more carbon in the soil better than any uncharred organic matter," Lehmann said.


 http://www.livescience.com/environment/060222_amazon_soil.html

Brian

Comments

Hide the following 2 comments

Dont make your own....

25.02.2006 13:30

Brian...

"Take some normal soil, add a handful of charcoal, a bunch of leaves and a dollop of cow poop"

Charcoal huh, very good for the environment that is.

Why not just let the leaves and cow poop rot for a bit and that will give you your precious carbon.
If your worried about retaining nutrients in the charcoal.... add a bit of clay.

Bob


Remineralising soil

25.02.2006 16:07

You can remineralise soil with rock dust from certain types of quarry. You get huge, healthy plants from undepleted or remineralised soil and it can repair at least some of the damage caused by persistent monoculture. You can buy rock dust from some commercial operations or you can bag it yourself ( quarries aren't guarded ).

 http://www.organicgarden.org.uk/remineralisation

Danny