Fundamental Experiment on the Dissolved Oxygen Consumption by Bottom Sediment in Static Water

Laboratory experiments are carried out in order to investigate the relationship between the mechanism of dissolved oxygen (DO) consumption by the bottom sediment and time-varying process of DO consumption in static water, and the factors which influence DO consumption are examined. The experimental results have shown that DO in water decreases at the initial stage and the rate of DO consumption becomes small with time. It is also found that DO consumption increases when the chasms or holes are formed on the surface of bottom sediment and the sediment volume expands due to generation of nitrogen, hydrogen sulfide or methane gas.