FIELD OBSERVATIONS OF A HIGH TURBIDITY LAYER IN WESTERN AREA OF ARIAKE SEA AND LABORATORY EXPERIMENTS OF OXYGEN CONSUMPTION BY SUSPENDED SOLIDS

Abstract

In order to investigate the formation mechanism of oxygen-deficient water mass in western area of Ariake Sea, field observations were made in September 2002 and July 2003. A high turbidity layer, in which the concentrations were 20∼40 ppm, was formed near the bottom by strong currents during the observation periods. When DO concentration was high, turbidity and DO concentrations near the bottom have a negative correlation. The oxygen consumption rate by SS took 7 times the value of SOD, and it suggests that the oxygen consumption by SS plays an important role for formation of oxygen-deficient water mass in the western area of Ariake Sea.