Revealing historical fire regimes of the Cumberland Plateau, USA, through remnant fire-scarred shortleaf pines (Pinus echinata Mill.)

Michael C Stambaugh,Joseph M Marschall,Erin R Abadir

doi:10.1186/s42408-020-00084-y

Abstract

BackgroundVegetation of the Cumberland Plateau (USA) has undergone dramatic transitions since the last glaciation and particularly since the onset of widespread logging and twentieth century fire exclusion. Shortleaf pine (Pinus echinata Mill.), one of the most fire-dependent conifers in the US, occurs throughout the Cumberland Plateau, but its abundance has declined dramatically since Euro-American settlement and continues to decline. To better understand the historical ecology of fire within the natural range of shortleaf pine, we reconstructed fire regimes at three new sites throughout the central and southern Cumberland Plateau region based on fire scars on shortleaf pine trees.ResultsFire event chronologies extended back to the seventeenth century and revealed historical fire regimes that were frequent and dominated by dormant-season and low-severity events. Fires occurred on average every 4.4 to 5.3 years at the study sites before widespread Euro-American settlement, and were more frequent (2.3 to 3.8 years) following settlement. Cumberland Plateau fires may be linked to adjacent ecoregions such as the Eastern Highland Rim to the west. Among all sites, we found that long-term trends in fire activity were similar and fit into a regional waveform pattern of fire activity likely driven by humans (i.e., Native American depopulation, European settlement, and twentieth century fire exclusion).ConclusionsThe decline in shortleaf pine and other fire-dependent ecosystems across the Cumberland Plateau is due to multiple interacting factors and, based on these data, frequent fire should be considered a historically important ecological driver of these systems.

Highlights

Vegetation of the Cumberland Plateau (USA) has undergone dramatic transitions since the last glaciation and since the onset of widespread logging and twentieth century fire exclusion
The Cumberland Plateau field surveys resulted in the selection of three sites for fire history reconstruction located at Johns Mountain Wildlife Management Area (JMT), Savage Gulf State Natural Area (SAV), and Angel Hollow (ANG) (Fig. 1)
A total of 131 fire scars were dated, with event years ranging from 1667 to 1948, and up to 16 fire scars recorded on a single tree

Summary

Introduction

Vegetation of the Cumberland Plateau (USA) has undergone dramatic transitions since the last glaciation and since the onset of widespread logging and twentieth century fire exclusion. While fire history studies from fire scars have shown historically frequent fire in several eastern US ecosystems (Guyette et al 2006a, 2012), such data are lacking across broad regions because of both insufficient spatial coverage of studies and the continuous loss of physical evidence due to decay and disturbances such as logging, agriculture, and burning. Though presently the world’s broadest expanse of hardwood-forested plateau (approximately 70% coverage), Cumberland Plateau vegetation has undergone dramatic changes since the last glaciation, since Euro-American settlement (EAS)

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