SEDIMENTARY HUMIC ACIDS IN THE CONTINENTAL-MARGIN OF THE ROSS SEA (ANTARCTICA)

Humic acids (HA) extracted from Antarctic marine sediments were charac terized using different techniques (FTIR, NMR, Thermogravimetry, Eleme ntal Analysis and Ionic Exchange Chromatography). Antarctic sedimentar y HA show a greater content of nitrogen and a predominant aliphatic na ture when compared with data reported in the literature for non Antarc tic HA samples. Some differences in the structures, such as the presen ce of aromatic carbon rings, carbohydrates, fatty acids, etc., have be en observed, as a function of sampling zones. The differences are prob ably due to a different humification process, possibly depending on di fferent trends of temperature and salinity measured down to the water column.