Several studies have been made on the effect of the artificial reef construction on the algae and seaweed. But little is known about the transition of the algae on the surface of newly constructed reef This paper is intended as an investigation of the transition of the algae and seaweed on the artificial reef in the Hirota bay.
The results of this investigation showed that the transition of the ecosystem on the artificial reef could be showed by the index of diversity, and that the algae and seaweed on the artificial reef would be influenced by the wave and current around the artificial reef.