Terra Preta Or Amazon Dark Soil, What It Is And Its Composition

Since the dawn of time, humans have needed shelter, food and water to survive. Hunter-gatherers would usually be on the move, but civilisation starts with settlement and then agriculture. As soon as people settle the problems of being in one place arise; they need to grow food. In turn they discard or dispose of waste products for sanitation purposes.

Fires would have been needed for heat at night and to cook food. As a result, the fire would have produced small amounts of charcoal/ash. Also in preparing food there would have been organic food waste from plant materials to fish skin and animal bones. Finally, each family/small community would have produced human waste. This waste may have accumulated in small piles or middens and left to rot. A few weeks or months later the wastes would transform into compost and enrich the surrounding soil.

Seeds in the diet of these early settlers would have passed through them and into the middens. In turn new plants would have grown. We see evidence of this same process today in piles of compost or solid human sewage. Also, plants in the surrounding soil may have started to flourish around these small mounds of decaying material.

Larger populations lead to civilisation and agriculture

The settled way of life with improved agriculture often leads to population growth with luck civilisation follows. To sustain a large population you must have a large and ‘reliable’ food source to feed everyone. It is a surmise on our part, but once these settlers had noted the effects of their middens there was no stopping them. They had invented a new form of agriculture.

As the settler population grew more food they needed more food, so each process got a little more industrialised. The settlers may also have used fires or clay kilns to burn trees and plant materials to create charcoal. Alternatively, they may have burnt the trees and plant life directly where it stood and this provided organic carbon amendment to the surrounding soil, similar to the result of a forest fire.

The community transported their wastes, human/animal in clay pots to larger ‘landfill’ sites. This may also have helped to prevent the spread of disease. We know that biochar acts as an odour suppressor, so this may also have also been a driver for adding it onto these piles.

The above is our representation of how it may have come about, but none of it is proven.