Joint 72nd Annual Southeastern/ 58th Annual Northeastern Section Meeting - 2023

Paper No. 20-12
Presentation Time: 1:30 PM-5:30 PM

HOLOCENE PEATLAND FIRE RECONSTRUCTION IN THE APPALACHIAN MOUNTAINS OF WEST VIRGINIA, USA


CHIMEZIE, Joan1, WILLARD, Debra A.2, JONES, Miriam C.2 and HOTCHKISS, Sara C.1, (1)Department of Botany, University of Wisconsin-Madison, Birge Hall, 430 Lincoln Dr., Madison, WI 53705; Center for Climatic Research, University of Wisconsin-Madison, 1225 W. Dayton St., Madison, WI 53706, (2)U.S. Geological Survey, Florence Bascom Geoscience Center, 12201 Sunrise Valley Dr, MS 926A, Reston, WI 20192

Charcoal records are useful in interpreting and reconstructing fire history, especially in conjunction with pollen records of past vegetation, but records of peatland fires in the Eastern United States are sparse. Here we investigate how local fire regimes have interacted with peatland development and vegetation change as a result of both climate and human impacts during the Holocene. We collected cores from two small peatlands: Big Run Bog (BRB) and a bog in the Dolly Sods Wilderness Area (DS), 25km apart, and located in the Allegheny Mountain section of the Appalachian Plateaus physiographic province, in West Virginia (WV). The BRB spans the period from 18000 cal yr BP to present, whereas the DS record is younger, spanning at least the last 5000 cal yr BP. We examined macroscopic (>125 µm) charcoal morphotypes and accumulation rates to understand local fire history and indicators of vegetation burned. Charcoal concentrations at BRB were high from ~18000-15000 cal yr BP. Charcoal morphotypes include fragments of conifer wood, which agrees with our pollen record, indicating that conifers were dominant during this time interval. Charcoal concentration decreased between 15000 cal yr BP and 12000 cal yr BP, but a few peaks in charcoal accumulation provide evidence of local fire; pollen assemblages show a concurrent decline in conifers. Soon after 12000 cal yr BP, charcoal concentrations decreased. In the late Holocene, charcoal concentrations at both BRB and DS increased. A sharp increase in charcoal concentration in the uppermost samples of BRB tracks the increase in Ambrosia in our pollen records, which coincides with the onset of forest clearance by European colonists. DS also recorded this rise in charcoal and a corresponding rise in Ambrosia pollen, but the charcoal abundance here is variable. Historical evidence has indicated extensive logging between 1880 and 1980 CE. The charcoal records from BRB and DS Bog therefore show strong influence of both climate and human impacts driving fire in this region of the Appalachian Mountains.