Abstract
Barren ground is widely distributed in the sea area. The coastal structures to make the algae place have been constructed for about ten years. However, it is feared that the decrease in the effect of seaweed creation by the aged deterioration of the substrate. The occurring condition of Barren ground is that feeding pressure of sea urchin is greater than growth rate of seaweed. It is necessary to calculate the growth of the seaweed and the revenue and expenditure of sea urchin's food consumption correctly.
In this study, the quantification of the seaweed biomass was examined by factors of environment with a remarkable change. Variability characteristics of the seaweed amount and a physical environment were clarified. Finally, the improvement of the calculation method of the amount of the seaweed was achieved.
