CHARACTERIZATION OF BELIZE CAVE SEDIMENTS TO EXAMINE PALEOENVIRONMENTAL IMPLICATIONS FOR SOCIO-ENVIRONMENTAL CHANGES DURING THE MAYA COLLAPSE

In this study, carbon isotope concentrations were used to construct a record of paleoenvironmental changes in Mesoamerica and climatic impact upon the area dating back to the time of the Maya. Sediment cores were collected from two Belize caves (one each from Actun Chapat and Jose Cueva) and organic material from each core was analyzed via radiocarbon dating, through physical analyses with a Malvern Mastersizer 2000 particle analyzer, along with descriptions that include color, layer properties, grain type, and any other discernable properties, and were finally analyzed geochemically by extracting organic acids to analyze carbon isotopes (ratio of ¹³C/¹²C) to recreate paleoenvironmental conditions and ultimately record the history of sedimentation, vegetation, and land use and how these conditions are affected by climate and by human activity in the former Mayan region. Down core characterization of the almost one-meter cores reveals changes in sedimentation rates and types, which differ in the two areas. Thus far, in the two processed cores and were able to discern several different unique layers that indicate sedimentological changes likely caused by changes in climate, land use, or erosion, or a combination of those factors. Drier layers and several fine anomalies slowed analysis and extracting organic matter for charcoal was successful from many layers, but not all. Changes in carbon isotope values indicate variability in vegetation regimes from C₄ to C₃ plants, along with possible land use differences. Collectively, these sediment cores reveal the applicability of using cave sediments to reconstruct the paleoenvironment and possible changes during the Maya occupation of the area.