Fire History of Gum Swamp and Black Pond in Eastern Tennessee, U.S.A., from Macroscopic Sedimentary Charcoal

Eastern Tennessee and Great Smoky Mountains National Park are biological hotspots in which settlement by Native Americans and Euro-Americans dramatically changed the landscape through land clearance and changes in fire occurrence. I present two local fire histories using macroscopic sedimentary charcoal, one from a highly managed area and one from private agricultural land. Gum Swamp (35°35' N 83°50' W) is a pond located in Cades Cove, Great Smoky Mountains National Park that experiences seasonal drying. The 0.94 m sediment profile extends to about 425 cal yr BP, based on an AMS radiocarbon date on charcoal fragments at mid-depth in the profile. Black Pond (35°37' N 84°11' W) is a spring-fed sinkhole surrounded by agricultural fields. The 2.88 m sediment profile is expected to extend to about 3000 yr BP based on comparison with a sediment core previously recovered and analyzed for pollen and microscopic charcoal by Patricia Cridlebaugh in her Ph.D. dissertation research at the University of Tennessee. AMS radiocarbon dates for the new profile are pending. The macroscopic charcoal record of Gum Swamp shows an increase in charcoal concentrations between the early 1800s and the 1950s associated with Euro-American land clearance and settlement. A decrease in charcoal concentration from the 1950s to the present likely signals fire suppression in Great Smoky Mountains National Park. This record is correlated with an earlier microscopic charcoal record completed by Jean Davidson in her M.S. thesis research at the University of Tennessee. Both records show similar trends in charcoal concentrations, but Davidson’s chronology, which is based on radiocarbon dating of bulk sediment, differs from the chronology presented here. My results suggest that the Gum Swamp record spans less time than Davidson proposed. The macroscopic charcoal record from Black Pond shows high charcoal concentrations during an interval tentatively correlated with indigenous occupation, based on Cridlebaugh’s chronology. Moderate charcoal concentrations characterize the period of subsequent Euro-American settlement, followed by low concentrations in recent times. The similar trends in macroscopic and microscopic charcoal at Black Pond and Gum Swamp suggest that the microscopic charcoal previously investigated may largely signal local fires in these small watersheds.