Collaborative Research: Calibration of Sr:Ca and d18O Proxies of the Southern Quahog, Mercenaria Campechiensis, to Reconstruct Late Holocene Climate, SW Florida

University Of Florida, Gainesville FL

Investigators

Abstract

This award will calibrate Strontium/Calcium ratios and delta oxygen-18 isotopes from modern shells of the southern quahog clam, Mercenaria campechiensis, as proxies for temperature and salinity, respectively, to generate low-latitude, preindustrial, Late Holocene climate data derived from archaeological quahog shells. To determine seasonal and spatial variability in physical and chemical water properties, temperature, salinity, delta Oxygen-18 (water), delta Carbon-13 (dissolved inorganic carbon), and Strontium/Calcium (water) in the Charlotte Harbor estuary, southwest Florida, will be measured/sampled during the wet and dry seasons. These data will be used to construct predictive-model shells for comparison with observed data. The southern quahog will be calibrated by comparing observed shell data with predictive-model shells. The PIs will also evaluate whether Strontium/Calcium and delta oxygen-18 (shell) in archaeological quahogs can track temperature and salinity, respectively, by comparing the predictive model to the geochemistry of modern shells and to known archaeological data. The successful completion of this research will yield multidisciplinary data with applications to a number of problems in the area of global climate change. The outreach component of this work will be facilitated by the Florida Museum of Natural History's Randell Research Center (RRC). Public education will target K-12 students (including inner-city children) and teachers, the retired community, and others, via volunteerism, newsletters, websites, tours, docent training, exhibits, lectures, and workshops. In all these venues, the RRC promotes public archaeological and ecosystem stewardship as part of its mission.