名取川に見られる河床形状特性とその変遷

抄録

In the alluvial reach of the Natori river, two distinctive morphological features can be seen. The reach from the upstream of Taihaku bridge to the confluence with the Hirose river is characterized by unstable, braided configuration while the reach downstream of the confluence is rather stable. This study provides a theoretical explanation for the distinctions between two reaches in a same river by the use of the theories of stable channel cross-section of straight gravel and sand-silt rivers, and the theory of bar formation. The differences of grain size and bed slope are found to cause such a contrast.