Lidar Imaging Helps Anthropologists See Beneath the Vegetation in Belize
March 07, 2012
Categories: Inside UNM
Each summer University of New Mexico Associate Professor of Anthropology Keith Prufer and his students travel to the ancient Mayan city of Uxbenká, located in southern Belize where they labor to understand what happened to the Mayas who lived there when the Maya states were the most important political entities in Central America.
Uxbenká has always been off the beaten path, even in the Classic Period (AD 200-1,000) when the ancient Maya were thriving. But sometime after AD 800, much of the population apparently left. Prufer has spent the last several years working with students trying to understand how many people once inhabited this part of Belize, how they lived and whether the changing environmental and political climate had a major impact on the isolated community. The research is funded by the National Science Foundation and the Alphawood Foundation.
Last summer, they collaborated with National Science Foundation's National Center for Airborne LiDAR in Houston, Texas and flew a plane to Belize to map a 127 square kilometer area near the modern Mopan Maya Santa Cruz Village and the ancient community of Uxbenká. LiDAR, Light Detection and Ranging (also LADAR), is a remote sensing technology that can create highly detailed maps of large areas by illuminating the landscape using pulses from a laser. The accuracy of LiDAR allows for the creation and display of 3D models representing the bare earth, vegetation and surface structures over large areas. The plane flew for five days, carefully working with ground GPS units to accurately map the landscape. Prufer now has the results of that mapping effort. The information is incredibly valuable.
But using the LiDAR scans Prufer can peer through the vegetation and clearly see the remains of old structures.
"It's an alternative to the past where we would have to hack lines through the forest to find anything because we couldn't see. Now we can see things on these maps and target them," he said.
Prufer returns to Uxbenká in April to begin another season of field work, and this time the research group will look more closely at some of the sites made visible by the LiDAR images. They also use the images for other applications.
"What is really amazing is how it allows us to look at the degree of landscape transformation," Prufer said. "These are not natural hill tops. They have been completely shaped and cut and filled. Our excavations show that as well. It really begins to allow us to get at the massiveness of this landscape modification. All of these areas are completely leveled and flattened. So hundreds of thousands of cubic meters of rock and soil were cut and filled in by hand in the past."
Prufer says they hope to eventually quantify the amount of labor needed to make these modifications and have a better idea of the number of people who actually inhabited this area in the past. His students are also trying to piece together how events in the more populous states in the Mayan region might have affected this remote city.
Only a few hundred people live near Uxbenká today. About 100 are employed by the project each year as the anthropologists arrive for another season of research. Prufer says they are curious about the excavations, but they are very interested in learning how the scientists determine which lands are most likely to be productive. Farmers move their fields often by cutting parts of the surrounding vegetation, and they want to know more about the chemistry of the soils.
Prufer is mentoring several students in their doctoral work on various aspects of the research in Belize. A recent article in the Journal of Archaeological Science by Brendan J. Culleton, a recent Ph.D. student who worked on the project, and co-authored by Prufer and Douglas J. Kennett from Pennsylvania State University outlines recent findings.
This is a long term project for Prufer. It's his eighth field season in Belize and he says he and his students have a solid research foundation for making significant contributions to understanding the development and decline of past societies in their ecological context.
Media contact: Karen Wentworth (505) 277-5627; email: firstname.lastname@example.org