HABITAT CHARACTERISTICS OF CORBICULA JAPONICA IN SAND BARS OF THE KISO RIVER TIDAL REACH

Abstract

In the Kiso river tidal reach is formed sand bars and embayments around groins. And this area is habitat of a brackish bivalve, Corbicula japonica. Corbicula japonica feeds suspended organic matters in brackish water, they could play a role of water purification. However, distribution of bivalves in sand bars of tidal area has not been clarified. A purpose of this study is to clarify habitat characteristics of Corbicula japonica in estuarine sand bars. Habitat distribution and physical characteristics of habitat about this bivalve was investigated to focus attention on surface environment on sand bars. As a result of this study, fine-grain fraction rate of sediment on the sand bar has an effect on inhabitation of Corbicula japonica. And it was clarified that the habitat condition varies with ignition loss and submergence rate at the sand bar.