Reconstructing the Rio Bravo Watershed and Ancient Maya Wetland Agriculture

Keywords: Geoarchaeology, Remote Sensing, Stable Carbon Isotopes, Wetlands
Session Type: Virtual Paper Abstract
Day: Friday
Session Start / End Time: 2/25/2022 02:00 PM (Eastern Time (US & Canada)) - 2/25/2022 03:20 PM (Eastern Time (US & Canada))
Room: Virtual 7

Abstract

Recent research using LiDAR and geoarchaeological methods have revealed expansive networks of ancient Maya wetland canals and fields in Northwest Belize (Beach et al., 2019). The largest area of these fields lies along the Rio Bravo and has never been studied before, only being recognized through airborne LiDAR survey in 2016. While these newly re-discovered fields are contained in a protected area, wetlands that are not protected in this area are rapidly disappearing and being replaced with intensive agriculture (Doyle et al., 2021). This study area, therefore, provides a lens to understand ancient floodplain management in the same places where modern farmers are expanding operations. First, we develop a machine learning model to extract the canals and raised fields from the LiDAR data to quantitatively estimate their size and patterns. Next, we present initial chronologies from AMS radiocarbon dating of charcoal and stratigraphy. These excavations revealed two buried soils, which suggest multiple significant changes in floodplain conditions through the time of ancient Maya occupation. Stable carbon isotope analysis reveals that the Maya were likely growing maize intensively in the floodplain both before the construction of the raised fields as well as on the fields. This large ancient agricultural system demonstrates the importance of wetland agriculture for the Maya in this region, and reflects a long history of human management and adaptation to environmental changes.