The terra preta of the Brazilian Amazon are anthropogenic dark earths, characterised by
enhanced levels of soil fertility and popular locally for growing cash crops such as papaya
and mango. These crops are said to grow three times faster than on surrounding land, a
landscape characterised by soils of generally low fertility. Although the terra preta occur in
small patches averaging 20 ha, sites as large as 350 ha have been reported (Smith, 1999).
Similar soils have not only been identified elsewhere within the region, namely Ecuador and
Peru, but also beyond, in West Africa (Benin, Liberia), and the savanna of South Africa
(Lehmann et al., 2003).