Fig. 2. Principal components (PC) analysis of the microbial community structure based on ester-linked fatty acid methyl ester (EL-FAME) profiles in a ponderosa pine forest soil that was scarified in 1981, burned in a high-severity surface burn in 2002, or both. Mineral soil samples (0–10-cm depth) were collected and analyzed in June 2005. Individual samples as well as the average PC scores for each treatment are shown along with standard error bars (±1). The amount of variability explained by each PC axis is shown in parentheses.