Re: Terra Preta

[Ray Evans Harrell]

Amongst many Indian groups the belief is that reality can only be expressed by metaphor and story.    So science is hidden within the stories.   It is deliberate and speaks to the same reality that modern science invests in Mathematics.   It is a difference between the thought processes of Europeans and American Indians.    It is interesting that Europeans Americans are skeptical about anything that is native in origin but tell tireless stories about Descartes sitting in a fireplace and inventing science or Newton's Apple.   As long as there is a lack of respect the world will never get population under control because there can be no dialogue.    It would make more sense to start from acceptance than from an obnoxious skepticism.    However,   As you said to my cousin, "Dream on."    I enjoyed your response to her.    We are basically in agreement on many things.   Ray ----- Original Message ----- From: Steve Kurtz To: [EMAIL PROTECTED] Sent: Monday, March 18, 2002 4:26 PM Subject: Terra Preta Ray, This was new to me, so I did a google search. Main website http://www.geo.uni-bayreuth.de/bodenkunde/terra_preta/ abstracts from conference: http://www.geo.uni-bayreuth.de/bodenkunde/terra_preta/Agenda_ From a quick look, there must be trees/bushes burnt to create the stuff. Certainly interesting, but may work only in specific conditions. Steve one abstract: The Terra Preta phenomenon – a model for sustainable agriculture in the humid tropics Bruno Glaser, Ludwig Haumaier, Georg Guggenberger & Wolfgang Zech   Abstract Many soils of the lowland humid tropics are thought of being too infertile to support sustainable agriculture. However, in the Brazilian Amazon region, within the landscape of infertile soils, patches of sustainably fertile soils known as Terra Preta do Indio occur. These soils not only contain higher levels of nutrients such as nitrogen, phosphorus, potassium, and calcium, but also higher stocks of stable soil organic matter. Frequent charcoal findings and highly aromatic humic substances suggested that residues of incomplete combustion of organic material (black carbon) are a key factor for the persistence of soil organic matter in these soils. Our investigations showed that Terra Preta soils contained up to 70 times more black carbon than the surrounding soils. Due to its polycyclic aromatic structure black carbon is chemically and microbially stable and persists in the environment over centuries. Oxidation during this time produces carboxylic groups on the edges of the aromatic backbone, which increases the nutrient holding capacity. We conclude that black carbon could act as a significant carbon sink and is a key factor for sustainable and fertile soils especially in the humid tropics. There is strong evidence that permanent or semi-permanent agriculture itself created sustainably fertile Terra Preta soils known. -- http://magma.ca/~gpco/ http://www.scientists4pr.org/ Anyone who believes exponential growth can go on forever in a finite world is either a madman or an economist.—Kenneth Boulding