Fire Severity Modeling of Sagebrush-Steppe Rangelands in Southeastern Idaho

Abstract

The potential for high-severity fires to affect changes in rangelands is considerable, and for this reason, assessing fire severity is critical. We explored fire severity modeling in rangelands by applying post-fire field observations to Satellite Pour l'Observation de la Terre 5 (SPOT 5) imagery using Classification Tree Analysis (CTA) techniques at two 2005 burns. The results of these analyses demonstrate that CTA is equally adept at classifying areas of low severity as well as those with high severity with reliable accuracy (66-100%). Furthermore, the CTA technique is fairly uncomplicated to apply and provides an error assessment upon which land managers can better justify their recommendations.

Assessing the susceptibility of semiarid rangelands to wildfires using Terra MODIS and Landsat Thematic Mapper data

“…Grass is a common component of the fuel load in south-east Idaho, and accumulated fuel loads can burn intensely and severely. The development of fuel stockpiles and the prevalence of cheatgrass (Bromus tectorum), an invasive annual grass, have made the fuels on Idaho's rangelands increasingly problematic (Weber et al 2008b). Historically, rangelands in south-east Idaho experienced wildfire throughout a 2-3-week period in late summer (F. Judd, pers.…”

“…Satellite remote sensing is an evolving technology providing regional and global imagery that has been used for many wildfire studies (Fernandez et al 1997;Miller and Yool 2002;Wooster et al 2003;Lentile et al 2006;Weber et al 2008b). These studies include both observational and modelled data and have been conducted on active fires and for detecting post-fire burn extent.…”

“…(Miller and Yool 2002). Similarly, post-fire field observations coupled with Satellite Pour l'Observation de la Terre 5 (SPOT 5) imagery have been used for fire-severity modelling of sagebrush steppe rangelands in south-eastern Idaho (Weber et al 2008b).…”

“…NBR and dNBR are key indicators of burn severity and can be used to infer many post-fire effects such as fire extent (Holden et al 2005) and fire severity classification (Brewer et al 2005;Smith et al 2005). For example, incorporating Classification Tree Analysis (CTA) techniques and postfire field survey data, NBR along with various other band ratios was used to assess the severity of fire occurring in rangelands of Idaho (Weber et al 2008b). Furthermore, these reflectance indicators derived from remotely sensed data were widely used for fire studies in savannahs and semiarid environments (Smith et al 2005;Fisher et al 2006;Weber et al 2008a).…”

Spatiotemporal Trends in Wildfires across the Western United States (1950–2019)

“…The results of this analysis can be informative and help interpret temporal trends. For the purposes of this study, wildfire severity is defined as the extent to which a fire affects the vegetation and soils in a given area, as indicated using the Differenced Normalized Burn Ratio (dNBR) [33,34]. Statistical analyses performed as part of this study were derived using dNBR layers generated from Landsat 5 TM, Landsat 7 ETM+, Landsat 8 OLI, and Sentinel-2 satellite images.…”