Prior low-severity fires reduce the risk of persistent forest loss from subsequent fires

Gui, S.; Zhang, S.; Zhang, Y.; Wang, J. A.; Zhu, Z.; Goncalves-Souza, T.; Ombadi, M.; Liu, Y.; Tang, J.; Reich, P. B.; Goldstein, B. P.; Zhu, K.

doi:10.64898/2026.08.23.746551

bioRxiv · 10.64898/2026.08.23.746551

Prior low-severity fires reduce the risk of persistent forest loss from subsequent fires

Gui, S.·Zhang, S.·Zhang, Y.·Wang, J. A.·Zhu, Z.·Goncalves-Souza, T.·Ombadi, M.·Liu, Y.·Tang, J.·Reich, P. B.·Goldstein, B. P.·Zhu, K.

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Abstract

Intensifying fire regimes threaten forests globally, but the risk of persistent post-fire forest loss and its potential mitigation remains poorly quantified. We analyzed millions of wildfires worldwide from 2001 to 2024 and tracked recovery in satellite-observed forest structure and ecosystem function. Post-fire persistent forest loss, indicated by modeled non-recovery to pre-fire conditions over decadal timescales, affected 57.1% of burned forest area globally since 2001, with hotspots in Pacific temperate and southern boreal forests. We then identified 'crucial fires' as events exceeding a stringent modeled-risk probability threshold for persistent structural or functional non-recovery, with fire severity strongly predicting this loss. This severity dependence revealed a management pathway, as locations with prior low-severity fire experienced lower severity in subsequent wildfires and had lower modeled probability of becoming crucial. Under a model-based counterfactual scenario, applying the estimated severity attenuation was associated with a 7.6% reduction; the top 1% of road-accessible areas accounted for 35% of this reduction. These results provide a global framework for identifying where wildfire threatens forest resistance and where targeted low-severity fire management like prescribed fire might be used to combat global forest loss.

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Gui, S., Zhang, S., Zhang, Y., Wang, J. A., Zhu, Z., Goncalves-Souza, T., Ombadi, M., Liu, Y., Tang, J., Reich, P. B., Goldstein, B. P., Zhu, K.. 2026-08-24. Prior low-severity fires reduce the risk of persistent forest loss from subsequent fires. https://doi.org/10.64898/2026.08.23.746551

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