Abstract
The artificial reefs (ARs) deployed on a sandy-muddy bottom at depths of
10 to 16 m in Beppu Bay, southern Japan were investigated using ROV
(Remotely
Operated Vehicle) and scuba diving from 2008 to 2017. The ARs were made of
cubic
concrete blocks overlaid by two porous panels consisting of seashells on top
side. Young thalli of Sargassum sp. appeared on the panels in the
first year. The
dominant macroalgal communities changed from Sargassum sp. to Ecklonia
kurome
after several years. Macroalgae were more abundant on the porous panel than
on
the other sides of the concrete blocks after ten years. The biomass of the
benthos
(shell fish, barnacles and bristle worms) on the surveyed blocks in March
2017 was
455.12 g/m2 on the porous panel part and 366.25 g/m2
on the smooth part of the
concrete blocks. The installation of porous panel material facilitated more
attachment
of seaweeds than on the smoother part of the ARs making it more advantageous
in creating seaweed beds.
