BIOLOGICAL AND CHEMICAL OXYGEN CONSUMPTION ABOVE THE SEDIMENTS IN THE INNERWESTERN PART OF ARIAKE SEA

Abstract

 Oxygen consumption experiment was performed in two fixed points in order to clarify the fractionation of oxygen consumption in the bottom layer of the bay head of Ariake Sea. Chemical oxygen consumption in Hamakawa offshore (T14) showed 28% of the total oxygen consumption, has been shown to vary by the mortality of benthic animals and sediment reduction due to the formation of hypoxic water. In contrast, in an oceanographic observation tower of the Saga University chemical oxygen consumption accounted for 77% of total oxygen consumption. In addition, aerobic decomposition by microorganisms, so-called "oxygen consumption associated with the decomposition of the direct organic matter" did not show a big contribution. Differences of contribution rate of chemical oxygen consumption has been suggested to be due to the difference of suspended material composition. From these, oxygen consumption process was suggested significantly different in the two observation points.