大規模出水による中規模河床形態の変化と河道内湧水の生態機能に関する研究

Abstract

Instream springs have attracted attentions as a measure for restoration of ecological function in the lower reaches of the Tenryu River, where riverbed environment has been deteriorated by reduction of sediment dynamism and prolonged turbidity derived from the series of dams constructed upper stream. We found that Ayu fish made reproduction in the spring channels and the number of spawned eggs showed a positive correlation with the flow discharge of the spring channel. The reproductive success of the fish was expected to increase with increasing the number of spring channel larger than 12, 500m 2 in area which were created by combination of large and small floods.