2025-11-17 カリフォルニア大学バークレー校（UCB）
＜関連情報＞
- https://news.berkeley.edu/2025/11/17/prescribed-burning-helps-store-forest-carbon-in-big-fire-resistant-trees/
- https://esajournals.onlinelibrary.wiley.com/doi/10.1002/eap.70111
- https://tiisys.com/blog/2023/12/13/post-130561/
シエラネバダ山脈の火災危険を軽減するためのさまざまな経路の炭素コスト Carbon costs of different pathways for reducing fire hazard in the Sierra Nevada
Yihong Zhu, Daniel E. Foster, Brandon M. Collins, Scott L. Stephens, Robert A. York, Ariel T. Roughton, Emily E. Y. Moghaddas, John E. Sanders, John J. Battles
Ecological Applications Published: 02 November 2025
DOI:https://doi.org/10.1002/eap.70111
Abstract
Restoring a low-intensity, frequent-fire regime in fire-prone forests offers a promising natural climate solution. Management interventions that include prescribed fire and/or mechanical treatments have effectively reduced fire hazards in the Western United States, yet concerns remain regarding their impact on forest carbon storage. This study used results from a long-term, replicated field experiment to assess the impacts of a restored disturbance regime on carbon dynamics in a Sierra Nevada, mixed conifer forest. The carbon consequences of the treatments were compared to a dynamic baseline of untreated controls (Control). After 19 years of wildfire mitigation, all treated stands stored less carbon than Control, but a larger proportion was sequestered in wildfire-resistant pools (i.e., large trees or fire-resistant species). Notably, only the most intensive treatment regime—thinning, mastication, and prescribed fire (Mech+Fire)—became a net carbon source by Year 20 (−60 MgC/ha). Annual average net ecosystem productivity (NEP) in Control and prescribed fire-only (Fire, 5.6–5.8 MgC/ha/year) more than doubled that of the mechanical treatments (2.0–2.1 MgC/ha/year). Moreover, temporal trends diverged. By the 3rd post-fire interval, the live vegetation carbon accumulation stalled in Control (0.9 ± 1.0 MgC/ha/year, mean ± SE) and accelerated in Fire (6.6 ± 1.2 MgC/ha/year). In contrast, surface fuel recovery was initially faster in Fire but slowed significantly by the 3rd interval, suggesting that the increased productivity under a frequent-fire regime does not necessarily lead to rapid surface fuel buildup once the regime is established. A simulated wildfire in Year 20 killed 6×–16× more live tree carbon in Control (46% mortality). Still, Control maintained the highest post-fire carbon storage. Despite the inherent carbon costs of wildfire mitigation, our 20-year study highlights management pathways that minimize the trade-off between wildfire hazard and carbon storage in Sierra Nevada mixed conifer forests.
