Another
very good introductory article on Terra preta:-
http://www.philipcoppens.com/terrapreta.html
What we know + a slighly different perspective e.g.,
Philip Coppens
Since the latter half of the 20th century, two leading thoughts have come to the forefront of humanity: one is the possibility that we can destroy our planet – and whether our industrialised economy is killing the planet, the second is so-called “terraforming” other planets – making them inhabitable and suitable for human habitation.
Both “techniques” transform an existing ecosystem and reside in opposite camps – destruction and creation.
Though topical, and for many perhaps theoretical, it is not a purely modern issue, an outcome of Man’s conquest of space, or the science fiction generations that have grown up in the 20th century.
During that same century, it has become clear to science that people in the Amazon have created and used similar techniques – two millennia earlier.
and
Though some of the secrets of this soil have been discovered and will help in provide great help to many impoverished regions, some ingredients of Terra Preta remain unidentified – or at least difficult to reproduce.
In fact, one missing ingredient is how the soil appears to reproduce.
Science may not know the answer, but the Amazonian people themselves argue that as long as 20cm of the soil is left undisturbed, the bed will regenerate over a period of about twenty years.
A combination of bacteria and fungi are believed to be the transformative agents, but the agents themselves remain elusive from the scientific microscopes.
