RECORDS OF LAKE LEVEL CHANGE FROM THREE PONDS IN SE ALABAMA

The range of hydroclimate variability in the Southeastern United States through the Holocene remains relatively unquantified due to a dearth of paleoclimate records. Here we present data from a project on three ponds <500 m apart in southeastern Alabama that ultimately aims to characterize changes in lake level over the last several millennia. Preliminary data include sedimentology and stratigraphy, loss-on-ignition, and magnetic susceptibility. At the base of all three lake sediment cores, there is a coarse yellow sand unit that noticeably fines upward. Subsequently there is a gradational transition to dark brown peat that dominates in the uppermost sediments. This unit is occasionally interrupted by thin layers of yellowish silty sand. We interpret this sedimentology to represent a period of increasing lake levels, punctuated by occasional drops in lake level. The transition into the dark brown peat unit dates to between 6000 and 8000 years BP, which agrees well with previous work by Watts and others, that suggested an increase in effective moisture around 8500 years BP in the SE US. Future work will include the collection of transect cores to further quantify lake levels as well as expanding core collection to other lakes in the southeast.