Effect of Installation of Oxidized Slag Boulders on Aquatic Habitat in Artificial Channel

Abstract

No previous reports exist of using oxidized slag exceeding 20 cm in size as boulder. In this study, aquatic organisms inhabiting rivers—including river shell, shrimp, other fish, and eels—were released into a channel. Observation periods of one week each were established in September and November. In a rectangular horizontal channel, the consecutively assembled boulders were installed by using approximately 20 cm of oxidized slag and natural stones. As a result, water quality analysis from water samples showed almost no leaching from the slag. Furthermore, no abnormalities were observed in the behavior of aquatic animals. Additionally, the aquatic organisms utilized the spaces between the gravel without distinguishing between the slag and the natural boulders. Measurements of the flow velocity field verified that the flow between boulders was effective for resting and movement behavior.