The laser technology (LIDAR) applied in the jungle of Belize has revealed the true extent and impact of the settlements of this civilization. A huge network of Mayan channels and crops was found.
In the summer of 2016, a small twin-engine plane flew over the Belize jungle in Central America, just 500 meters from the treetops. The artifact was equipped with a technology that is revolutionizing many fields of science, including archeology. This device, known as LiDAR (an acronym for English, Light Detection and Ranging or Laser Imaging Detection and Ranging ), launched 6,000 million pulses of laser light to the ground and received about 11,000 million bounced pulses. Many of the rays sneaked through the gaps between the trees, hit the ground and, upon returning, allowed the cartography to be mapped to the surface of the jungle.
The results of that scientific flight, published now, reveal that under the trees are the remains of a huge network of transport channels and fields forming a grid that were built by the Mayan civilization. The researchers estimate that the network occupied 14 square kilometers, almost three times more than the urban center of a city like Madrid.
The excavations in the land made in six points show that the area was active especially during the last part of the classic period, about 1,200 years ago. It was a stage of maximum expansion of this civilization that occupied southern Mexico, Guatemala and Belize. The most recent remains reach the postclassic, some 900 years ago, and near the time when the Maya left their cities and their civilization collapsed for reasons that have not yet been clarified.
Mayan cities like Tikal, in Guatemala, are famous for their majestic temples. They came to have a population density comparable to that of some current cities. Until before the LiDAR arrived, evidence of how to feed such a large population had been scarce.
“It is the first time that the existence of a large area of cultivation and transportation of the Maya has been demonstrated using laser imaging and confirming it with archaeological tests and field dating,” says Tim Beach, a researcher at the University of Texas at Austin (United States). United) and co-author of the finding, published Tuesday in the Proceedings of the American National Academy of Sciences. The work confirms previous studies in which the LiDAR had revealed the true extent of other more emblematic Mayan settlements.
The work explains that although the ancient Mayan channels have been filled with soil and sediments, they are still less elevated than the cultivation areas and that water flows through them in the wet season.
One of the channels that still has a watercourse during the wet season.
The study suggests that one of the cultivated areas analyzed, known as Birds of Paradise, comprised a network of 71 kilometers of crisscrossed channels about three meters wide, and also reveals other agricultural areas hitherto unknown. The Mayans could pass from one river to another and reach the Caribbean Sea through these channels, the work says.
This large cultivation field was next to two population centers called Gran Cacao and Akab Muklil, where there are no majestic buildings as in other Mayan cities.
Judging by the extension of the fields, the researchers highlight the important environmental impact that the Mayan civilization had on their environment. To gain arable land, they burned larger and larger forest areas and drew canals and plantations of corn, squash or avocado, as indicated by the isotopes rescued from the sediment. There is also evidence of shellfish culture and ceramic remains.
“These activities increased carbon dioxide and methane emissions,” say the study authors.
«Before the industrial era, records show that the greatest increase in methane happened in the first millennium of our era, just at the time of maximum expansion of the Maya and other pre-Columbian cultures in South America, when there were also practices similar deforestation to grow rice in China. This is what we call the early anthropocene, the first time human civilizations had a global impact on the planet, ”explains Beach.
In 2012, a study led by NASA stated that the deforestation of the Maya was so severe that it influenced the local climate. Droughts became stronger and that lack of rainfall could be one of the determining factors of the abandonment of large cities and the collapse of civilization.
“Curiously,” says Beach, “in this site we have found remains dating back to the period after the abandonment of Tikal and the other great Mayan cities. It is possible that here, farther north and with possibilities of cultivation, the Maya survived longer, ”he points out. In fact, the researchers point out that the moments of maximum expansion of these crops coincide with two important environmental phenomena: sea level rise and drought.
“It is a very convincing study that demonstrates the importance of Mayan crops in wetlands,” said Anabel Ford, director of the Mesoamerican Research Center at the University of California, Santa Barbara (USA).
The expert emphasizes that this discovery presents a different development model from the big cities like Tikal, where another type of agriculture, the cornfield (denomination of a portion of land and the techniques of cultivation of corn, beans and squash), did not leave archaeological traces Even so, it is skeptical that the Mayan impact was so decisive in the climate. “Until it is demonstrated that it was a very intensive agriculture, we cannot affirm it,” he says.
Source: El País