Carbon sequestration

Carbon added to the soil in this elemental form is quite stable and lasts a long time in the soil.

Terra preta

Terra preta is a soil type that is found in parts of the Amazon. After much debate it is commonly accepted that it is a man made soil type. Unlike the surrounding soils of the rainforest, terra preta is fertile and does not deplete in nutrients like the forest soils around it.

soil pit comparing terra preta and forest soil

Charcoal appears to be the key to making terra preta. Improvements of yield on poor soils are huge with terra preta. It appears that mimicking this unique soil in temperate climates will be of any benefit, this is something I'd like to investigate. In the very least it may control nutrients leaching into water and rebuild soil carbon levels.

While the Yeoman site sits on the valley floor, there are areas in the region where the soil has some similarity to the rainforest soils. I feel these soils would likely benefit from this modification and encourage anyone who has these orange/red clay soils on their site to research this phenomenon and experiment themselves.

This powerpoint hosted on youtube is an excellent primer on terra preta.

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