PALEOECOLOGY AND HUMAN USE OF WETLANDS IN THE THREE RIVERS REGION, NORTHWESTERN BELIZE

In 2016, we conducted a Lidar survey of wetland systems in Northwestern Belize, which provided extensive new evidence of anthropogenically modified fluviokarst systems and wetland agricultural environments at an unprecedentedly large scale. Here we report on wetland sediment cores from two locations within this multi-hectare wetland system as well as our 2017 excavations on archaeological mounds, also located within the wetland. These wetland cores provide a multiproxy record for wetland change over time, both natural and anthropologically driven. First, using five AMS dates and stratigraphy, we developed an age-depth model for one core. Second we used several proxies to study the paleoecological fluctuations and wetland development within this system. The proxies included microcharcoal, elemental geochemistry, pollen, and carbon isotopic analysis. The swamp genesis began with the transition of a floodplain soil to a wetland , dating at ~1675 years BP . A rising water table, either anthropogenically or naturally derived, caused peats and sediments to deposit on top of terrestrial soil. This changed the microfaunal community significantly within the system. Pollen analyses shows that maize cultivation occurred over the duration of the Maya Classic (1650-1000 BP) and into the Postclassic as well, suggesting cultural resilience at that time. Third, evidence from nearby Maya mound excavations suggests that the ancient Maya exploited these wetlands for multiple uses at least until the Late Classic with Postclassic reentry. Based on these multiple proxies and compared with regional climate records and Maya history, we are studying the timing, duration, formation, and spatial extent of human uses of these anthropogenic wetlands. These lines of data may further enhance our knowledge of human resilience and resource extraction in the face of long term regional drought cycles.