Fig. 8. Dynamics of C mineralization of Al–organic matter (OM) precipitates (as a percentage of initial C) during 7 wk of incubation at pH 4.5 and 20°C. The Al–OM precipitates were produced from dissolved organic matter solutions from the Oa and Oi horizons of a beech and a spruce forest at two pH values and four Al/C ratios. Mean values and standard error of three replicates.