Abstract
In Shinto Yamaguchi Prefecture Iwakuni, steel-making slag of different chemical and physical properties were put into the waters, the varification of the algal bed substratum formed were carried out. The purpose of this study was to carry out the verification of the fish-gathering effect, which its seaweed function creates an irregularity shape to foundation was constructed by steel-making slag (particle size:30-85mm). From the seagrass beds construction epiphytic, after one month Ectocarpus siliculosus, after 6 month (without irregularities) in the construction area large seaweed, after 18 month the dominant seaweed around natural algal bed substratum Ecklonia kurome, appeared. In the wet weight of seaweed epiphytic in June 2015, rather than a difference depending on the type of steel-making slag, there was a difference due to particle size. After the construction of the algal bed substratum by steel-making slag, the number of fish increased compare to before the construction. However we could not confirm the effect of fish-gathering due to the presence or absence of unevenness of about 0.5 m.
