Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1086/662675
Titel (primär) Understanding shifts in wildfire regimes as emergent threshold phenomena
Autor Zinck, R.D.; Pascual, M.; Grimm, V.
Quelle American Naturalist
Erscheinungsjahr 2011
Department OESA
Band/Volume 178
Heft 6
Seite von E149
Seite bis E161
Sprache englisch
Keywords forest fire mode; wildfire; threshold phenomena; regime shift; climate change; criticality; self-organized criticality; power-law scalings
Abstract

Ecosystems driven by wildfire regimes are characterized by fire size distributions resembling power laws. Existing models produce power laws, but their predicted exponents are too high and fail to capture the exponent’s variation with geographic region. Here we present a minimal model of fire dynamics that describes fire spread as a stochastic birth-death process, analogous to stochastic population growth or disease spread and incorporating memory effects from previous fires. The model reproduces multiple regional patterns in fire regimes and allows us to classify different regions in terms of their proximity to a critical threshold. Transitions across this critical threshold imply abrupt and pronounced increases in average fire size. The model predicts that large regions in Canada are currently close to this transition and might be driven beyond the threshold in the future. We illustrate this point by analyzing the time series for large fires (>199 ha) from the Canadian Boreal Plains, found to have shifted from a subcritical regime to a critical regime in the recent past. By contrast to its predecessor, the model also suggests that a critical transition, and not self-organized criticality, underlies forest fire dynamics, with implications for other ecological systems exhibiting power-law-like patterns, in particular for their sensitivity to environmental change and control efforts.

dauerhafte UFZ-Verlinkung https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=11850
Zinck, R.D., Pascual, M., Grimm, V. (2011):
Understanding shifts in wildfire regimes as emergent threshold phenomena
Am. Nat. 178 (6), E149 - E161 10.1086/662675