Characterizing fire-related spatial patterns in the Arizona Sky Islands using Landsat TM data

This research investigates the use of Landsat Thematic Mapper data to characterize spatial patterns in forests experiencing different fire severities and frequencies between 1943 and 1996. Spectral vegetation indices (SVIs) were used to compare spectral characteristics and spatial patterns for four categories of fire history: once burned, twice burned, multiple burned, and unburned. We quantified spatial patterns by calculating spatial statistics from several SVIs for each plot. These statistics were used in Spearman's Rank Correlation Analysis with fire history characteristics. We found significant relationships (p < 0.05) between many of the spatial measures (mean patch size, patch size coefficient of variation, mean patch fractal dimension, Shannon's Diversity Index, and Shannon's Evenness Index) and fire occurrence in the past ten, thirty, fifty, and fifty-four years; average fire-free interval; most recent fire-free interval; and time since the most recent fire.