Patch Characteristics of Post-Fire Landscapes in the Crown of the Continent Ecosystem, Montana, USA

The combination of the effects of fuels, weather, and topography result in a diversity of burning conditions which create a mosaic of fire severity patches on the landscape. This project focused on quantifying those patches and patterns, and investigated the similarities and differences between post-fire landscapes. An accepted remote sensing based method of measuring fire severity, the Normalized Burn Ratio (NBR) was used to derive fire severity patches.

Traditional patch, class, and landscape metrics have been used widely to describe landscapes in terms of the composition and spatial arrangement of patches and classes of patches within them. The initial investigation employed traditional patch, class, and landscape metrics to describe the composition and configuration of the burned area in eleven study fires in the Crown of the Continent Ecosystem (CCE), and assess the range of landscape heterogeneity in those fires.

The power-law distribution is a heavy-tailed distribution where events of small magnitude, or size, are represented very frequently in the distribution, while large events occur infrequently. This distribution is observed for many disturbance processes such as landslides and earthquakes. The second component of the study was an investigation of the distribution of severity patch sizes within each of the fires, and employs the power-law concept to describe and interpret the patch-size distribution. When applied to fire severity patches, analyses of power-law distributions yield an important measurement of the characteristics of post-fire landscapes, which may be used as a basis for making fire to fire comparisons. These comparisons can be used to monitor deviations in fire processes that may be due to a variety of factors, including management activities and changing climate conditions.

Principal Investigator: Josh Rodriguez