Marine organisms attaching on test pieces of mild steel surface cathodically protected, the control steel plate, and FRP plate which were exposed in a intertidal zone of 0.00∼+1.40m in water level during the duration of 476 days were studied.
The amount of attaching organisms and the numbers of species were the most on the cathodically protected specimens, next being FRP and then the control steel plate. The results showed that organisms attached and multiplied even on the mild steel surface in the intertidal zone by providing cathodic protection. The action of covering protection on the mild steel surface by attaching of organisms would be maintaind by applying a protective current. The highest effect of covering protection and most abundant of attaching organisms was observed in the water level of 0.00∼+0.60m.

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[in Japanese]

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1. Four species of bryozoans which are potential shallow-water foulers have been tested for their tolerance to various salinities.
2. The salinities used in the experiments ranged from 3.75ppt to 37.5ppt and the responses of the zooids in each grade were evaluated.
3. Colonies of Zoobotryon verticillatum (15-37ppt) and Membranipora tuberculata (20-37.5ppt) were found to tolerate a wide range of salinities.
4. Colonies of Bowerbankia gracilis (25-35ppt) and Vesicularia papuensis (20-30ppt) were found to be moderately euryhaline.
5. The present experimental study supports an earlier ecological inventory on the distribution of bryozoans in the area, demonstrating that the low salinity conditions result in fewer numbers and species.

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