Characteristics of Humic Acids in a System of Geochemically Linked Bog Landscapes

The elemental and structural-group compositions and paramagnetic properties of the humic acids of peat occurring at different depths of peat deposits of various geneses have been investigated. With decreasing the depth of peat occurrence, the extracted humic acids were characterized by a decrease in the Н/С ratio and the amount of carboxyl and methylene groups and an increase in the signal intensity of organic paramagnetic centers (PMCs), which indicated an increase in the aromatic conjugation structure. The change in the amount of PMCs in the humic acids of peat along the depth of a deposit was directly dependent on the Fe3+ content.