Archaeological Dark Earth

Hatahara Site with Manacapuru phase urns and anthropogenic dark soils, ca 600 AD. Photograph by Val Moraes – Central Amazon Project

Fertile soil “built” by the ancient people of the Amazon

Other names:
terra-preta, terra-morena, terra-de-índio, TPI

In brazilian-portuguese:
Terra Preta Arqueológica, terra-preta, terra-morena, terra-de-índio, TPI


Article topics:

1. What is dark earth?
2. Eleven thousand years ago
3. Four thousand years ago
4. A few tens of years ago
5. For hundreds of years
6. Nowadays


1. Dark Earth, or Dark Archaelogical Earth (DAE), is a type of dark and fertile soil found in the Amazon basin in ancient settlements of pre-Columbian native populations. From the earliest scientists to the present day, the theorists of a wild and sparsely populated Amazon considered dark earth as a whim of nature. But this type of soil is being intensively studied by a new strain of rebellious archaeologist and owes its coloration to the high carbon content. Also included in its composition are plant remains, animal bones, faeces and urine, and a large quantity of ceramic shards, which makes it definitely be of human origin. It is very stable and remains in the ground for thousands of years. Mulatto earth is lighter or brownish in color. It is less fertile than the dark earth, but it is more fertile than the surrounding earth and may seem like an intermediate step to reach the black land itself.

2. Eleven thousand years ago, we imagined flying over an Amazon forest that has no end. In a clearing, at the edge of a stream, a small village of few nomadic families struggles in the daily task of survival. After a day of hunting and gathering of wild fruits they meet around the central campfire to prepare the daily food. On the floor of that little world and its surroundings are the bones and the rest of food, barks and seeds, charcoal and fire ash, urine and feces. After a certain period, when the resources of the area are scarce, the leader of the group decides to change the village. So it is, for several generations, and they follow in the ancestral tracks, accumulating the memory of the ancients.
The official history says that this was the millennial landscape of the human occupation of the region, had no agriculture and also had no culture, just a wild people fighting for survival. So it was, say the doctors of the academy, until the arrival of the Europeans, when the official history of the continent began. And so it is, even today, they conclude: as are the indigenous village today, so have always been in the past.

3. Four thousand years ago, the descendants of that same human group, after several returns on the same site, discover that the peach palm seeds of the last visit are now a palm grove that grows lush over the dark soil, rich in organic matter. The seeds of other fruits collected in other times, also sprouted and offer an easy food. They learn to accumulate organic waste on the outer edge of the village. The fields of cultivation grow and so the population. It is the beginning of a new historical cycle: the village realizes that the place can guarantee its permanent sustenance and agriculture is born. More plants are domesticated and so they have been tweaking that rich soil that makes plants thrive. Growing villages occupy more territory, now they have cassava, açai, buriti, chestnuts, piquiá, tucumã … They even have a complex system of rituals, which we now call culture.

4. A few tens of years ago, in that same place two powerful tractors drag a chain of steel 50 meters from each other. The chain, between the two machines is knocking down everything without mercy. In a matter of minutes, thousands of years of evolution are laid to the ground. An extraordinary amount of animals suddenly lose their reference: there is no more nest, there is no more food, there is nothing else. To complete, there follows an annihilating fire and everything turns into a silent and apocalyptic desert.
This is the current story of many places similar to this: they say it is progress. Thousands of hectares of forest give way to soy or grass fields. Tons of pesticides are dumped on land to increase production and eliminate pests. Soy and meat are destined for international markets, nothing is left in the Amazon except the poison that contaminates rivers, fish and their inhabitants.
By irony of luck or by some mysterious plan, the deforested lands let incomprehensible signs appear, huge squares, circles and other geometric figures of up to 300 meters, are geoglyphs, messages from a distant era.
But how? The scientists all agreed that the Amazon had no way to develop a civilization. The forest land is extremely leached and totally unviable for agriculture … but these imposing geometric figures say the opposite.

5. For hundreds of years, the riverside populations and the caboclos of the mainland have used the archaeological dark earth, in practice overturning the myth that the region’s soils are poor and unsuitable for agriculture. Dark soil is used for subsistence farming without any management practice and the soil is still fertile.
With the support of archeology and geochemistry, the aim is now to produce the black archeological land. The benefits are many. The creation of a “new dark earth” would prevent the use of archaeological sites for subsistence planting and would help the small farmer, as well as make possible the use of this land in low fertility soils, such as cerrado. (Dirce Kern)
A new generation of researchers is in the bush, leaving the traditional academics who from the top of their chairs resist furious the evidence. Young researchers, archaeologists, anthropologists, agronomists, biochemists, etc. they challenge a convenient version of history and write it on new foundations: advanced civilizations flourished in the Amazon, the rainforest is a “cultural forest”.

6. Nowadays, this type of soil is only known by researchers and some brave pioneers, but it seems that few is given importance to the subject, in the Amazon as in Brazil. All that is of Indians is associated with prevailing prejudice of prehistoric and primitive. But the black earth as well as being a great discovery for humanity is the simplest and most efficient answer to the problems of climate change, among other things. These dramatic changes are caused by the extraction of carbon from the soil and emission into the atmosphere, and the production of dark earth on a large scale would create the opposite effect by re-storing carbon in the air to the earth. And on earth, carbon finds the most stable place to stay and help life on the planet. While in Brazil the incalculable value of dark earth is neglected, more research and applications flourish abroad. See the links in English and the article “New Dark Earth”.


archeology  |  before history  |  indigenous legacy  |  dark earth  |  history  |  sustainability  |  golden age
Article Version:

Last Modified:
3/12/2017 6:15:43 PM

Article extracted from Amazoniapedia

Amazoniapedia is a Laboratory of Studies of the Amazonian Region, a long-term project by photographer Leonide Principe*. As a starting point, the project recognizes and embraces the awareness of an ancient civilization that already existed in the Amazon and that can become a source of inspiration for ecological literacy*, community empowerment*, true sustainable agriculture (dark earth*), bioregionalism*,  happy degrowing*… and the formation of an authentic Amazonian feeling*.