Qualitative comparison between raw peat and related humic acids in an ombrotrophic bog profile

Physical and chemical properties of the peat core appear to show different conditions along the profile; in fact, these data could indicate the presence of 3 distinct zones in the bog: (i) an acrotelm, or zone of active decay, which may be oxygenated, depending on the season, (ii) a catotelm, which is always anoxic, and where only a very slow and partial organic matter decomposition is possible, and (iii) a “transitional” layer, in which complex interactions between organic and inorganic compounds most possibly happen. E4/E6 trend and FT-IR spectra on purified HA appear to confirm this hypothesis and underline different stages of humification of organic matter along the profile showing a greater degree of aromatic condensation in the deeper horizons than in the surface layer.