Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1086/650368
Title (Primary) The independent and interactive effects of tree-tree establishment competition and fire on savanna structure and dynamics
Author Calabrese, J.M.; Vazquez, F.; López, C.; Miguel, M.S.; Grimm, V.
Source Titel American Naturalist
Year 2010
Department OESA
Volume 175
Issue 3
Page From E44
Page To E65
Language englisch
Keywords establishment; grass-dependent fire; mean-field approximation; nonlinear interaction; pair approximation; spatially explicit model
Abstract Savanna ecosystems are widespread and economically important and harbor considerable biodiversity. Despite extensive study, the mechanisms regulating savanna tree populations are not well understood. Recent empirical work suggests that both tree-tree competition and fire are key factors in semiarid to mesic savannas, but the potential for competition to structure savannas, particularly in interaction with fire, has received little theoretical attention. We develop a minimalistic and analytically tractable stochastic cellular automaton to study the individual and combined effects of these two factors on savannas. We find that while competition often substantially depresses tree density, fire generally has little effect but can drive tree extinction in extreme scenarios. When combined, competition and fire interact nonlinearly with strong negative consequences for tree density. This novel result may help explain observed variability among apparently similar savannas in their response to fire. Paradoxically, this interaction could also render the presence of competition more difficult to detect in empirical studies because fire can override the characteristic regular spacing driven by competition and lead instead to clustering.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=9851
Calabrese, J.M., Vazquez, F., López, C., Miguel, M.S., Grimm, V. (2010):
The independent and interactive effects of tree-tree establishment competition and fire on savanna structure and dynamics
Am. Nat. 175 (3), E44 - E65 10.1086/650368