ALKANES OF PLANKTON AND BOTTOM SEDIMENTS FROM THE BALTIC SEA

The composition of alkanes of the total plankton was determined at 2 stations in the Gulf of Riga and in 6 recent sediment samples taken from the Daugava River [Latvia, USSR]-Gotland basin section. In the plankton, the domination of n-alkanes C15-C17 with the maximum concentration of n-C16 is evident. A partial pollution of plankton with petroleum hydrocarbons is indicated. The main peak of n-alkanes in the upper sediment layer in the low-temperature region of the spectrum is n-C17, whereas in the high-temperature region it is a series of odd n-alkanes C23-C31. Alkanes of the sediments under study are of a mixed biogenic origin (marine + terrestrial) with a different relationship between autochthonous and allochthonous components in different parts of the section and hardly containing any hydrocarbons of the petroleum series.