The distribution of major biochemical components in the waters of the Kuril Islands

In this paper, data are presented on the distribution of dissolved and particulate carbohydrates, proteins, lipids, and nucleic acids (NAs) in the waters of the Kuril Islands on both the Sea of Okhotsk and Pacific Ocean sides. By analyzing discrepancies in the absolute and relative concentrations of these substances, it is revealed that the waters of the Sea of Okhotsk have a strong bioproductivity. Changes in the absolute and relative conventrations of the major biochemical components of dissolved organic matter (DOM) and particulate organic matter (POM) are shown to result from the biological activity of auto- and heterotrophs of shelf and deep-sea ecosystems. Carbohydrates and proteins prove to be the major biochemical components of DOM and POM, respectively. Given high primary productivity, the carbohydrate content in POM is comparable to that of protein. In the southern Kuril area, the high concentration of dissolved and particulate NAs (which exceeds that of dissolved protein) and the high content of dissolved lipids are both strongly associated with local fish and zooplankton distribution. In the shelf and pelagic waters, biological factors dominate the horizontal and vertical distribution patterns of the major biochemical components of DOM and POM. The hydrological regime only affects these patterns in the straits of the Kuril Islands. For the first time, the biochemical composition of DOM and POM in the sea surface microlayer (SML) is characterized. In this microlayer, the concentrations of major biochemical components of DOM and POM are, to a great extent, higher than in the underlying layer.