FIG 5.

Percent degradation of C₁₀ to C₅₀ hydrocarbons after 6 weeks of microcosm incubation following the addition of crude oil and monoammonium phosphate. Bars represent standard errors. Different letters over columns indicate significant differences between treatments based on a Tukey HSD post hoc test following one-way ANOVA. The sterile (noninoculated) controls were rerun after the initial experiment, as the original controls experienced contamination. The incubation conditions were the same, and the C₁₀ to C₅₀ loss was compared to that of paired baseline samples that were frozen at the outset of this incubation. For treatments, n = 10, and for sterile controls, n = 3. INIT, sterile soil reinoculated with the initial soil; REG-M, sterile soil reinoculated with bacteria cultured on regular media; CO-M, sterile soil reinoculated with bacteria cultured on media containing crude oil.