"Terra Preta de Indio" (Amazonian Dark Earths, earlier also called “Terra Preta do Indio” or Indian Black Earth) is the local name for certain dark earths in the Brazilian Amazon region. These dark earths occur, however, in several countries in South America (Brazil, Ecuador and Peru) and possibly beyond.
As ecologically rich as the rainforest may appear, the soil it stands in is unsuited to farming – largely a result of the incessant rain washing away all nutrients. But those pockets of soil that are Terra Preta, are suitable for farming and thus form an out of place patch of fertility in an otherwise harsh environment. In fact, it has the ability to maintain nutrient levels over hundreds of years. According to Bruno Glaser, a chemist at the University of Bayreuth, "If you read the textbooks, it shouldn't be there." According to a study led by Dirse Kern of the Museu Goeldi in Belem, Terra Preta is "not associated with a particular parent soil type or environmental condition", suggesting it was not produced by natural processes...
