2014 Volume 70 Issue 2 Pages I_1062-I_1067
To clarify water quality improvement function and its change factor in pro-environmental seawall, we investigated artificial tidal flat that made on pro-environmental seawall in Tokyo Bay. The artificial tidal flat was composed from three-different ground level bench at the front of seawall. Population dynamics of R. philippinarum suggested adult population disappearance occurred in the late summer to early autumn, because of the hypoxia was developed in Tokyo Bay. Therefore, amount of particulate nitrogen filtration and nitrogen fixation by the R. philippinarum was reduced, and R. philippinarum become a source of nutrients in these seasons. Hypoxia gave a serious damage for the water quality improvement function of pro-environmental seawall, therefore hypoxia provision was important for maintenance of function on pro-environmental seawall.
