Remote sensing of fire severity: linking post-fire reflectance data with physiological responses in two western conifer species

Friday, 19 December 2014
Aaron M Sparks1, Alistair MS Smith2, Crystal Kolden1, Kent G Apostol2 and Luigi Boschetti1, (1)University of Idaho, Moscow, ID, United States, (2)University of Idaho, Department of Forest, Rangeland, and Fire Sciences, Moscow, ID, United States
Fire is a common disturbance in forested ecosystems in the western U.S. and can be responsible for long-term impacts on vegetation and soil. An improved understanding of how ecosystems recover after fire is necessary so that land managers can plan for and mitigate the effects of these disturbances. Although several studies have attempted to link fire intensity with severity, direct links between spectral indices of severity and key physiological changes in vegetation are not well understood. We conducted an assessment of how two western conifer species respond to four fire radiative energy treatments, with spectra acquired pre- and up to a month post-burn. After transforming the spectral data into Landsat 8 equivalent reflectance, burn severity indices commonly used in the remote sensing community were compared to concurrent physiological measurements including gas exchange and photosynthetic rate. Preliminary results indicate significant relationships between several fire severity indices and physiological responses measured in the conifer seedlings.