Manaus Agile Amazonas' tourism and cultureThe international team will try to find in the Amazon the so-called geoglyphs, which are large geometric drawings made on the ground.
The unmanned aircraft that will be sent to the region is equipped with a laser that analyzes and searches for areas where there may have been constructions thousands of years ago . The aim of the project is to determine how large these millennial communities were and to what extent they altered the local landscape.
The researchers announced the initiative during the annual meeting of the American Association for the Advancement of Science (AAAS), in the city of San Jose, California. The project, a partnership between agencies and institutions in Brazil and Europe, has already secured a US$1.9 million grant from the European Research Council. Depending on the data obtained, they can also be used to draw up policies for sustainable use of the forest. But the most important issue is to try to understand the scale and activities of the populations that lived in the Amazon at the end of the period before Europeans arrived in America, i.e. the last 3,000 years before 1490.
Patterns in the soil
The international team will try to find in the Amazon the so-called geoglyphs, which are large geometric designs made in the ground. More than 450 of these geoglyphs, in various geometric shapes, have been found in places where deforestation has occurred. But to this day no one knows exactly what these circles, squares and lines represent - there are indications that they were ceremonial centers.
What is known, however, is that they are evidence of collective behavior. "It's a heated debate now in New World archaeology," said Jose Iriarte of the University of Exeter in Britain. "While some researchers believe that the Amazon was inhabited by small groups of hunter-gatherers or else by small groups who farmed only for subsistence, who had minimal impact on the environment, and that the forest we see today was untouched for thousands of years, there is increasing evidence showing that this may not be the case."
"This evidence suggests that the Amazon may have been inhabited by large, numerous, complex and hierarchical societies that had a major impact on the environment; what we call the 'cultural park hypothesis,'" the scientist told the BBC.
Drone and satellite
Iriarte's project calls for the drone to fly over some areas of the forest that will serve as a sample. The laser attached to the drone will look for geoglyphs are hidden in regions not yet deforested. Part of the light from this laser, called "lidar" (light-activated radar) can get through the leaf barrier of the trees.
Several inspections will be made, and if the existence of the geoglyphs is confirmed, the scientists will try to determine specific changes that have been left in the soil and vegetation by the ancient inhabitants. These "fingerprints" will be able to be searched for by satellite images, making it possible to search a much larger area of the Amazon, larger than with the small drone. And, from this project it will be possible to evaluate how the Amazon can be managed in a sustainable way. According to Iriarte, it is not possible to speculate what future changes would be acceptable in the Amazon if there is not a complete understanding of how the forest has been altered in the past.
"We want to see what the human footprint is in the forest and then form a (use) policy, because it may be the case that the biodiversity we want to preserve is the result of a manipulation in the past of this forest," he explained.
