Shrubland fire behaviour modelling with microplot data

Abstract

Abstract:Fire behaviour modelling has been based primarily on experiments involving the measurement of a certain number of fires, where each variable is represented by an average value per fire. The main objective of this study was to examine if data collected from a microplot sampling design could be used to derive meaningful fire behaviour models. Three burns were conducted in low shrubland of Erica umbellata Loefl. and Chamaespartium tridentatum (L.)P. Gibbs in NE Portugal. Wind speed and aerial dead fuel moisture content varied from 5 to 27 km hr -1 and 14 to 21% respectively. Rate of spread and flame length ranged from 0.3 to 14.1 m min -1 and 0.2 to 3.1 m respectively. Rate of fire spread could be described effectively in terms of an empirical model with wind speed and fuel height as independent variables. The coefficients that describe the effects of wind speed and fuel height on fire propagation were consistent with published values for similar fuel types. Flame length was strongly related to Byram's fireline intensity. Microplot sampling is not free from methodological problems -which are discussedbut can be effectively used in field studies of fire behaviour.

Fire-vegetation interplay in a mosaic structure of Quercus suber woodlands and Mediterranean maquis under recurrent fires

“…Actually, plants constitute the wildland fuel that influence both fire ignition and 0378-1127/$ -see front matter Ó 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.foreco.2011.05.003 fire spread (Fernandes et al, 2000;Riccardi et al, 2007). The behavior of wildland fires (i.e.…”

“…The behavior of wildland fires (i.e. rate of spread, fireline intensity and energy released) is hypothesized to vary according to the structure of fuels, multi-or mono-layered (Fernandes et al, 2000;Hély et al, 2000;Tanskanen et al, 2005). In Mediterranean ecosystems, fuels are often heterogeneous spatially and in terms of composition (Gill and Groves, 1981;Keeley et al, 2005).…”

Changes in wildfire severity from maritime pine woodland to contiguous forest types in the mountains of northwestern Portugal

“…Both maritime pine stands (Cruz et al, 2008;Fernandes et al, 2009) and shrubland (Fernandes et al, 2000;Fernandes, 2001) are known for their high flammability and will usually experience stand-replacing wildfire. Fire selectivity studies (Nunes et al, 2005;Moreira et al, 2009;Silva et al, 2009) show that these cover types tend to be preferred by fire and burn proportionally more than other vegetation types.…”

Examining fuel treatment longevity through experimental and simulated surface fire behaviour: a maritime pine case study

“…Variation in rate of fire spread was further accounted for by understorey height, but because this variable did not differ between T10 and U25, its effect can only be ascribed to heterogeneity within the two fuel complex types or conditions. Field studies of shrub-dominated fire behav- iour often assume that fuel height integrates the fuel-complex structural attributes and effects on fire spread (e.g., Catchpole et al 1998;Fernandes et al 2000). The shift from E. umbellata (U25) to P. tridentatum (T10) as the dominant shrub species had no apparent effect on the rate of fire spread, in agreement with Fernandes et al (2000).…”

“…Field studies of shrub-dominated fire behav- iour often assume that fuel height integrates the fuel-complex structural attributes and effects on fire spread (e.g., Catchpole et al 1998;Fernandes et al 2000). The shift from E. umbellata (U25) to P. tridentatum (T10) as the dominant shrub species had no apparent effect on the rate of fire spread, in agreement with Fernandes et al (2000). Flame size expresses the heat released in the flaming front, which increases with rate of spread and the fuel available for combustion (Byram 1959).…”