Achaeologists Say Ancient South American Farmers Provide Example of Sustainability

So suggests a team of researchers studying an ancient farming system discovered in the Amazonian savannas of French Guiana.
A research team of archaeologists and paleoecologists have concluded that a group of pre-Columbian farmers living in the savannas surrounding the Amazonian rainforest in French Guiana, South America, practiced an agricultural and land-use technique that can serve as an example of sustainability for the future.

The research, published in the April 9, 2012 issue of the journal Proceedings of the National Academy of Sciences, shows that an indigenous people living in a savanna environment near the Amazon forest farmed without using fire, otherwise called "slash and burn" agriculture. By analysing pollen, charcoal and other plant remains across a period of more than 2,000 years, they determined that the early inhabitants of these savannas practiced 'raised-field' farming, which required the construction of cultivated agricultural mounds using wooden implements. This method resulted in improved drainage, soil aeration and moisture retention. Increased fertility was obtained by removing nutrient-rich muck from the flooded basin of the area and then depositing it on the mounds. The total system limited or eliminated the need to use fire, conserved soil nutrients and organic matter, and preserved critical soil structure. This is in contrast to the wide use of "slash-and-burn" agriculture and the use of fire for deforestation to achieve needed levels of production to sustain growing populations in the past and present, a major reason underlying the disappearance of environmentally critical ecosystems in today's world.

The study results contradict the long-standing belief that the arrival of Europeans after 1492, and the ensuing collapse of as much as 95 percent of the native populations due to disease and other means brought by European conquerors and settlers, led to decreased forest clearance and agricultural burning by the indigenous population. The prolific use of fire as an agricultural technique in these Amazonian savannas is thus actually a post-1492, as opposed to the generally accepted pre-1492, phenomenon. In fact, the research suggested a sharp increase in fires with the arrival of the first Europeans.

The discovery has implications for today.

"This ancient, time-tested, fire-free land use could pave the way for the modern implementation of raised-field agriculture in rural areas of Amazonia," says lead author Dr José Iriarte of the University of Exeter. "Intensive raised-field agriculture can become an alternative to burning down tropical forest for slash and burn agriculture by reclaiming otherwise abandoned and new savanna ecosystems created by deforestation. It has the capability of helping curb carbon emissions and at the same time provide food security for the more vulnerable and poorest rural populations."

Adds research participant Professor Doyle McKey of the University of Montpellier: "Amazonian savannas are among the most important ecosystems on Earth, supporting a rich variety of plants and animals. They are also essential to managing climate. Whereas savannas today are often associated with frequent fire and high carbon emissions, our results show that this was not always so. With global warming, it is more important than ever before that we find a sustainable way to manage savannas. The clues to how to achieve this could be in the 2,000 years of history that we have unlocked."

The study was conducted by scientists and scholars from the University of Exeter (UK), Natural History Museum of Utah (US), Centre National de la Recherche Scientifique (France), University of Edinburgh (UK), Université Montpellier II and Centre d'Ecologie Fonctionnelle et Evolutive (France). It was funded by two CNRS Programmes ('Amazonie' and 'Ingénierie Ecologique'), the Arts and Humanities Research Council and The Leverhulme Trust.
http://popular-archaeology.com/issue/march-2012/article/achaeologists-say-ancient-south-american-farmers-provide-example-of-sustainability