Study: 800-year-old farmers could teach us how to protect the Amazon

Apr 09, 2012
Raised fields in the Amazon savanna.

In the face of mass deforestation of the Amazon, we could learn from its earliest inhabitants who managed their farmland sustainably. Research from an international team of archaeologists and paleoecologists, published today in the journal Proceedings of the National Academy of Sciences, shows for the first time that indigenous people, living in the savannas around the Amazonian forest, farmed without using fire.

Led by the University of Exeter, the research could provide insights into the sustainable use and conservation of these globally-important ecosystems, which are being rapidly destroyed. Pressure on the Amazonian today is intense, with the land being rapidly transformed for industrial agriculture and cattle ranching.

By analysing records of pollen, charcoal and other plant remains like phytoliths spanning more than 2,000 years, the team has created the first detailed picture of land use in the Amazonian savannas in . This gives a unique perspective on the land before and after the first Europeans arrived in 1492.

The research shows that the early inhabitants of these Amazonian savannas practiced 'raised-field' farming, which involved constructing small agricultural mounds with wooden tools. These raised fields provided better drainage, soil aeration and moisture retention: ideal for an environment that experiences both drought and flooding. The fields also benefited from increased fertility from the muck continually scraped from the flooded basin and deposited on the mounds. The raised-field farmers limited fires, and this helped them conserve and organic matter and preserve .

It has long been assumed that used fire as a way of clearing the savannas and managing their land. However, this new research shows that this was not the case here. Instead, it reveals a sharp increase in fires with the arrival of the first Europeans, an event known as the 'Columbian Encounter'. The study shows that this labour-intensive approach to farming in the Amazonian savannas was lost when as much as 95 per cent of the indigenous population was wiped out as a result of Old World diseases, brought by European settlers.

The results of this study are in sharp contrast with what is known about the Columbian Encounter's impact on tropical forest, where the collapse of indigenous populations after 1492 led to decreased forest clearance for agriculture, which in turn, caused a decline in burning. This study shows that high fire incidence in these Amazonian savannas is a post-1492, rather than pre-1492, phenomenon.

Dr José Iriarte of the University of Exeter, lead author on the paper, said: "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. Intensive raised-field agriculture can become an alternative to burning down tropical forest for slash and burn agriculture by reclaiming otherwise abandoned and new savannah ecosystems created by . 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."

Dr Mitchell Power of the University of Utah said: "Our results force reconsideration of the long-held view that fires were a pervasive feature of Amazonian savannas."

Professor Doyle McKey of the University of Montpellier said: "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."

Dr Francis Mayle of the University of Edinburgh said: "We've got an unprecedented record of these Amazonian savannas that completely overturns previous assumptions about the way in which ancient cultures utilized these globally-important ecosystems."

Dr Stephen Rostain of CNRS said "These raised-field systems can be as productive as the man-made black soils of the , but with the added benefit of low ."

Explore further: Dead floppy drive: Kenya recycles global e-waste

Related Stories

Fires in Amazon challenge emission reduction program

Jun 03, 2010

Fire occurrence rates in the Amazon have increased in 59% of areas with reduced deforestation and risks cancelling part of the carbon savings achieved by UN measures to reduce greenhouse gas emissions from ...

Study identifies two types of savannas

Dec 08, 2005

Colorado State University scientists have determined the Earth maintains two types of savannas, which cover a fifth of the planet's surface.

Ecosystem management must consider human impact too

Oct 14, 2011

For a long time, ecologists have believed—and others accepted—that when it comes to whether a land mass is covered with forests or grasslands, climate controls the show. They thought that the amount ...

Recommended for you

Dead floppy drive: Kenya recycles global e-waste

23 hours ago

In an industrial area outside Kenya's capital city, workers in hard hats and white masks take shiny new power drills to computer parts. This assembly line is not assembling, though. It is dismantling some ...

New paper calls for more carbon capture and storage research

Aug 22, 2014

Federal efforts to reduce greenhouse gas emissions must involve increased investment in research and development of carbon capture and storage technologies, according to a new paper published by the University of Wyoming's ...

Coal gas boom in China holds climate change risks

Aug 22, 2014

Deep in the hilly grasslands of remote Inner Mongolia, twin smoke stacks rise more than 200 feet into the sky, their steam and sulfur billowing over herds of sheep and cattle. Both day and night, the rumble ...

User comments : 7

Adjust slider to filter visible comments by rank

Display comments: newest first

Telekinetic
3.7 / 5 (3) Apr 09, 2012
"One of the most important causes of deforestation in the Amazon is the cultivation of agricultural commodities such as soya, which is used mainly to feed animals. McDonald's has denied feeding its chickens with soya from the Amazon rainforest supplied by agricultural giant Cargill; however, not only did evidences prove this to be true, but also pointed out the soya farmers were linked to the use of slave laborers, illegal land grabbing and massive deforestation. It has been calculated that McDonald's and its suppliers are responsible for 70,000 km² of the Amazon's deforestation in the last three years."
A very simple thing to do if this bothers you is to boycott McDonald's. Your health will vastly improve to boot.
rikvanriel
3 / 5 (2) Apr 09, 2012
Another issue is that rainforest currently does not have the same economic value as farmland. It may be possible to change that by encouraging the growing of rainforest fruits and nuts, and by allowing low-erosion methods to extract valuable wood from the forest (leaving non-valuable trees and shrubs mostly intact, so the forest can re-grow quickly).
askantik
1 / 5 (2) Apr 10, 2012
If you are about protecting against deforestation and overall environmental preservation, stop eating animals. It's stupid to boycott McDonald's and continue buying the same product at grocery stores or other restaurants. Eating animals uses a much larger amount of water, fuel, and land to produce the same amount of protein as plants.

http://www.news.c...hrs.html
Telekinetic
3 / 5 (2) Apr 10, 2012
" It's stupid to boycott McDonald's and continue buying the same product at grocery stores or other restaurants."- askantic

Put it this way- it's not stupid- it's a start. Personally, I've chosen not to eat meat, but I don't expect others to commit to that. However, by boycotting McDonald's and spreading the word that they're destroying the rainforest, the next generation of consumers, by word of mouth, an effective tool to disseminate information, may go elsewhere for lunch.
Telekinetic
3 / 5 (2) Apr 10, 2012
"It's stupid to boycott McDonald's and continue buying the same product at grocery stores or other restaurants."- askantik

Put it this way- it's not stupid- it's a start. Personally, I've chosen not to eat meat, but I don't expect others to commit to that. However, by boycotting McDonald's and spreading the word that they're destroying the rainforest, the next generation of consumers, by word of mouth, an effective tool to disseminate information, may go elsewhere for lunch.
Telekinetic
3 / 5 (2) Apr 10, 2012
It's also disgusting and unhealthy food in general, contributing to the very real obesity problem in children and adults.
wiyosaya
2.3 / 5 (3) Apr 10, 2012
IMHO - the main driver of the obesity problem in the US is that most people have no clue how much food they really need, and guidelines on body weight from the USDA are far, far too high.

Also IMHO, it is far too simplistic to simply spout that eating animals is the problem. Perhaps eating factory farmed animals is what should be targeted, however, it is highly likely that sustainable farming actually leaves land used for raising animals in better shape than before the animals were raised there.

For a farm that knows animal farming in a sustainable manner have a look here http://www.polyfacefarms.com Their methods are much more like those of the indigenous cultures mentioned in this article.

BTW - I NEVER eat at McDonald's and NEVER would. Pure garbage there, not food at all.