Authors: Megan Walsh*, Central Washington University, Keith M Prufer, University of New Mexico, Douglas J Kennett, University of California Santa Barbara, Brendan J Culleton, Pennsylvania State University
Topics: Paleoenvironmental Change, Biogeography, Coupled Human and Natural Systems
Keywords: paleoecology, mangrove, charcoal, fire, climate, Holocene
Session Type: Paper
Presentation File: No File Uploaded
Relatively little is known about Holocene-length, human-environment interactions in the tropical lowlands of southern Belize, mostly due to the lack of viable sites from which to extract paleoecological records. Because permanently wet freshwater lagoons are rare, we investigate the use of sediment cores from coastal/riverine mangrove ecosystems as suitable sites for reconstructing paleoenvironmental change in adjacent lowland environments. We report on high-resolution macroscopic charcoal, sedimentological, and stable isotope data for sediment cores taken from mangrove ecosystems in the Toledo District of southern Belize. From these reconstructions we infer both a record of climatic change and human impacts on the landscape. Because naturally-ignited fires are rare in this region, the presence of macroscopic charcoal in the record almost certainly indicates the use of fire for forest clearance and swidden agriculture. One site in particular, Pork and Doughboy Lagoon, shows clear evidence of fire starting ca. 7400 calendar years before present, with increasing fire activity throughout much of the Holocene. It also records a clear drop in fire ca. 1300 calendar years before present and little burning after that time. Because of the nature of sediment accumulation into mangroves ecosystems and its complicated relationship with sea-level rise, paleoecological reconstructions based on these records must be interpreted with some caution. However, we believe these sites provide an opportunity to further our understanding of Holocene-length, human-environment interactions in southern Belize that would not otherwise be possible. We are also encouraged that our preliminary results support the findings of other paleoecological studies in the region.