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BackgroundAlthough fires can cause tree mortality or reduce post-fire growth in trees of all ages, and models exist that predict fire-induced mortality in mature trees, the development of predictive models of how fires impact younger trees has received less attention. AimsTo assess whether inclusion of fire behaviour metrics alongside pre- and post-fire sapling morphological traits improve the prediction of fire-induced tree mortality as compared to existing models. MethodsIn this study, we subjected Pseudotsuga menziesii (Mirb.) Franco var. glauca (Beissn.) and Pinus monticola var. minima Lemmon saplings to increasing levels of fire intensity and evaluated models to predict immediate and delayed post-fire mortality. Key resultsFor Pinus monticola, the optimal model relied on the post-fire crown volume scorched, while for Pseudotsuga menziesii the optimal model used flame height and fire radiative energy. We show that while Pinus monticola saplings exhibit immediate fire-induced mortality, Pseudotsuga menziesii saplings are prone to delayed fire-induced mortality. ImplicationsEven in younger trees, crown volume scorched and related metrics remain consistent predictors of fire-induced tree mortality. Future studies should track mortality over extended periods to ensure that developed models better represent delayed fire-induced tree mortality.
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Methods to assess fire-induced tree mortality: review of fire behaviour proxy and real fire experiments
Background The increased interest in why and how trees die from fire has led to several syntheses of the potential mechanisms of fire-induced tree mortality. However, these generally neglect to consider experimental methods used to simulate fire behaviour conditions. Aims To describe, evaluate the appropriateness of and provide a historical timeline of the different approaches that have been used to simulate fire behaviour in fire-induced tree mortality studies. Methods We conducted a historical review of the different actual and fire proxy methods that have been used to further our understanding of fire-induced tree mortality. Key results Most studies that assess the mechanisms of fire-induced tree mortality in laboratory settings make use of fire proxies instead of real fires and use cut branches instead of live plants. Implications Further research should assess mechanisms of fire-induced tree mortality using live plants in paired combustion laboratory and landscape fire experiments.
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- Award ID(s):
- 2242769
- PAR ID:
- 10584968
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- CSIRO Publishing
- Date Published:
- Journal Name:
- International Journal of Wildland Fire
- Volume:
- 34
- Issue:
- 1
- ISSN:
- 1049-8001
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1071/WF24136
