This study aimed to clarify the relationship between the spawning environments of masu salmon and river topography、 focusing on areas of sandbar geomorphology in which、 sandbars are formed by the natural effects of the river’s flow.[*]As a result、 many spawning beds were confirmed in areas of sandbar geomorphology、 where sandbars were formed by the natural effects of the river’s flow. Riverbed undulations were large in areas of sandbar geomorphology、 and many spawning beds were concentrated in the microhabitats (places of i/ia < 1.0) formed by this bed shape. These results represent important findings for the creation and maintenance of spawning environments for masu salmon. |