PROPERTIES OF HUMIC SUBSTANCES EXTRACTED FROM SEDIMENT AT GOCZALKOWICE DAM RESERVOIR

Studies of humification processes of sediments collected from various points of the Goczalkowice dam were conducted. The humic and fulvic acids were extracted from the collected sediment. For study of physico-chemical properties of humic and fulvic acids, EPR and NMR spectroscopy were used. For extracted humic and fulvic acids, concentration of free radicals and the g factor were determined with EPR. The presence of characteristic functional groups was confirmed with NMR spectroscopy. It was found that humic and fulvic acids extracted from sediment at 8 places of the Goczalkowice Reservoir are characterized by similar physico-chemical properties, which points to a similar composition of sediment in the whole reservoir. Humic acids are relatively high aromatized, have a low free radicals content and a low value of the g factor. They have condensed aromatic rings with side-aliphatic chains. However, the extracted fulvic acids are less aromatized than humic acids. They have a weakly formed aromatic core with the dominance of side-aliphatic chains. The influence of the depth of the lake on the content of oxygen functional groups in the extracted humic and fulvic acids was also observed.