Sensitivity to spatial and temporal scale and fire regime inputs in deriving fire regime condition class

Abstract

The Fire Regime Condition Class (FRCC) is a composite departure measure that compares current vegetation structure and fire regime to historical reference conditions. FRCC is computed as the average of: 1) Vegetation departure (VDEP) and 2) Regime (frequency and severity) departure (RDEP). In addition to the FRCC rating, the Vegetation Condition Class (VCC) and Regime Condition Class (RCC) are produced to indicate the status of each. FRCC assessments are applied as ecological condition measures across the U.S. for land and fire management plans, National Environmental Policy Act documents, project plans, burn plans, and agency reporting. Input data to FRCC computation include proportions of different successional stages within biophysical settings, estimates of current fire frequency and severity, historical reference conditions for successional stages, frequency, and severity, and the analysis area extent. Hydrologic unit maps, frequently referred to as Hydrologic Unit Codes (HUCs), for regional and local assessments and LANDFIRE Map Zones for national assessments commonly represent the analysis extent area. Mapping methods and quality have substantially improved with the development of the FRCC Mapping Tool with the associated User Guide and Tutorial. Our tests of mapping FRCC indicate that resulting FRCC metrics are highly sensitive to analysis scales of landscape extents, assumptions of current and historical fire regimes, and resolution of input maps. Examples of these effects and management implications are presented along with recommendations. We conclude that, when appropriately mapped, the Strata FRCC is a very useful measure of ecological condition, while the Stand FRCC is a very useful measure for prioritizing local vegetation and fuel treatments. The Regime Conditions of frequency and severity are highly useful for prioritizing wildland and prescribed fire options, as well as for designing vegetation and fuel treatments.

Parent Publication

• Proceedings of the large wildland fires conference; May 19-23, 2014; Missoula, MT

Citation

Tedrow, Linda; Hann, Wendel J. 2015. Sensitivity to spatial and temporal scale and fire regime inputs in deriving fire regime condition class. In: Keane, Robert E.; Jolly, Matt; Parsons, Russell; Riley, Karin. Proceedings of the large wildland fires conference; May 19-23, 2014; Missoula, MT. Proc. RMRS-P-73. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 237-246.