Organic Carbon Content in Dissolved and Particulated Forms in the Kara Sea Water

Data of suspended matter content, concentrations of dissolved and particulate organic carbon in the Kara Sea water for 2007-2022 are summarized. A difference in the distributions of dissolved (DOC) and particulate (POC) organic carbon in the water column during the autumn (September) and spring-summer (July-August) periods was revealed. An increase of concentrations of dissolved organic carbon was recorded both on the surface and in the water column in the summer. Analysis of the dependences of DOC concentrations on salinity showed that the increase in these concentrations is not associated with an increase in DOC concentrations in river runoff waters. There was also a significant increase in DOC and POC concentrations in phytoplankton bloom zones throughout the water column. Thus, a connection has been identified between seasonal increases of organic matter concentrations in the open part of the sea and the processes of phytoplankton blooming.