Methods for the Study of Soil Charcoal as an Indicator of Fire and Forest History in the Appalachian Region, U.S.A.

Charcoal particles in soils and sediments of the Appalachian region provide evidence of long-term fire history relevant to resource management and to studies of paleoclimate, vegetation history, and the effects of prehistoric and historic humans on the environment. Charcoal records of fire history are of low resolution in comparison to dendrochronological records, but reach well beyond the oldest trees in most areas, providing evidence of fires thousands or tens of thousands of years ago. We focus here on fire history reconstruction from soil charcoal, which provides site-specific evidence of past fires and potentially forest composition. Charcoal > 2 mm may be large enough for taxonomic identification, and of sufficient mass to enable AMS radiocarbon dating of individual particles. Soil mixing due to physical and biological factors creates soil profiles in the southern Appalachians in which charcoal age is not predictable from charcoal depth; soil charcoal records thus require many radiocarbon dates.