QUANTITATIVE EVALUATION ON ENVIRONMENTAL IMPROVEMENT FUNCTION OF ARTIFICIAL REEFS IN ACTUAL MARINE AREA

In Osaka prefecture, artificial fish reefs with a stirring function were located in the sea bottom to promote vertical mixing and attempting to reduce the occurrence of hypoxic water mass. These artificial fish reefs had functions of current control, stirring, and feed culture. It also has been verified that its effect was useful for vertical mixing and reducing the occurrence of hypoxic water mass. However, there were only a few samples that environmental improvement was quantitatively evaluated after setting artificial fishing tanks. In addition, there were a few associated research results with changes of current control and surrounding environment by artificial fishing reefs. In this research, we demonstrated the current control of the artificial fish reefs with diffusion state of turbidity, and verified bottom sediment improving that was resulted from current control effect.