US Geological Survey, Menlo Park, CA 94025.
Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA 94720.
Proc Natl Acad Sci U S A. 2022 Mar 22;119(12):e2116264119. doi: 10.1073/pnas.2116264119. Epub 2022 Mar 14.
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.
意义
我们首次评估了全新世晚期混交针叶林地上活立木的生物量。该生物量记录，结合当地原住民口头历史和火疤记录，表明原住民的烧垦做法，加上以自然闪电为基础的火发生制度，至少在加利福尼亚的一片森林中促进了其长期的森林结构和组成的稳定性，至少有 1000 年。这一记录表明，仅气候并不能解释所观察到的森林状况。相反，森林还受到频繁火灾的影响，包括原住民的有意点火。这项工作表明，需要进行大规模的干预，以实现支持森林恢复力和反映原住民影响的历史条件。
