Research leader

Dr Sarah Harris Research Leader

Research team

Christoph Rudiger Research Team
Nigel Tapper Research Team

End User representatives

Nick Bauer End-User

This project was commissioned and funded entirely by the Department of Environment, Land, Water and Planning, Victoria. 

Bushfires and planned burns occur annually in Victoria, impacting at a number of scales, from local effects on vegetation, hydrology and microclimates, to global effects such as emissions, affecting atmospheric chemistry, air quality, radiation balance and biogeochemical cycling (Andreae and Merlet 2001; Roy et al. 2002; Justice et al. 2003). However these effects vary across the landscape depending on the severity of the burn. Burn severity is a function of physical and ecological changes caused by fire (Cocke et al. 2005). Fires burn heterogeneously across landscapes, with sections of unburned and lightly burned patches interspersed among severely burned patches. This is due to variability in weather, type of fire, and patch to landscape vegetation patterns (Cocke et al. 2005). Information on burn severity and the variability of severity are essential for land managers and ecologists who need to understand ecosystem processes especially for vegetation recovery (Roy et al. 2006). This information is also essential for emergency services for making decisions on allocating time and resources. Burn severity information is also necessary to reduce uncertainty in emission estimates (Holden et al. 2005), water quality and yield, and provide information on how severity affects albedo and energy partitioning, all of which influence climate feedbacks (Cuevas-Gonzalez et al. 2008). The primary reason for undertaking burn extent and burn severity mapping in Victoria is so government agencies can quantify the results of their planned burning efforts and ultimately how this translates to changes in actual fuel load/structure, as this changes subsequent fire behaviour and consequently the fire damage potential.

Because fire causes a number of physical changes, including consuming different layers of vegetation strata, destroying leaf chlorophyll, exposing soil, charring stems and ground, changing soil chemical composition (White et al. 1996) and altering both above-ground and below-ground moisture (Epting et al. 2005), the burn severity can be related directly to the degree of this change. Such physical transformation causes variations in surface reflectance, albedo, moisture and temperature, which can be detected by means of satellite and airborne imagery (Cuevas-Gonzalez et al. 2008). Therefore, remotely sensed data can be used to measure the severity of a burn. 

There is a range of remotely sensed platforms, along with applicable methods for determining the severity of a burn. However, the choice of approach depends on particular circumstances, for example the conditions within the study region and the user’s spatial and temporal resolution needs. Additionally, some sensors do not cover the required part of the electromagnetic spectrum, and vary in the number of available spectral bands. The availability of data also determines which method can be employed, such as burn algorithms, image differencing, spectral mixture analyses or fire radiative power. While the availability of imagery is paramount to burn severity mapping, the methods need to be chosen in consideration of the landscape, especially vegetation type, fire history and the complexity of the terrain. A review of the state of knowledge and best practice of burn severity mapping for different environments and an understanding of the limitations and knowledge gaps is essential before undertaking a burn severity mapping research program.

Project objectives

The objectives of this project were to:

  1. Review the state of knowledge and practice for fire severity mapping using remotely sensed and other spatial information – with a focus on dissected forested environments;
  2. Provide advice on current methods using other spatial information and their known limitations for assessment of fire severity;
  3. Provide advice on critical knowledge gaps and a science and development program for addressing these.
Anders Siggins Conference Poster 2016
14 Aug 2016
The Victorian Government is committed to objective reporting of fuel management activities in terms of their...