Land management explains major trends in forest structure and composition over the last millennium in California's Klamath Mountains

Proc Natl Acad Sci U S A. 2022 Mar 22;119(12):e2116264119. doi: 10.1073/pnas.2116264119. Epub 2022 Mar 14.

Abstract

SignificanceWe provide the first assessment of aboveground live tree biomass in a mixed conifer forest over the late Holocene. The biomass record, coupled with local Native oral history and fire scar records, shows that Native burning practices, along with a natural lightning-based fire regime, promoted long-term stability of the forest structure and composition for at least 1 millennium in a California forest. This record demonstrates that climate alone cannot account for observed forest conditions. Instead, forests were also shaped by a regime of frequent fire, including intentional ignitions by Native people. This work suggests a large-scale intervention could be required to achieve the historical conditions that supported forest resiliency and reflected Indigenous influence.

Keywords: Indigenous management; carbon policy; forest biomass; land use; restoration.

MeSH terms

  • California
  • Conservation of Natural Resources*
  • Fires*
  • Forests
  • Humans
  • Trees