抄録
In the open-channel flow over flexible vegetation, the so-called honami motion is sometimes observed, which has relatively low frequency. The spatial heterogeneity of vegetation density in the vegetation layer when the honami behavior appears, and such a fact is focusedto analyze the flow with a heterogeneous vegetation layer. By coupling such an analysis of the flow with the model for deformation of an individual plant, a linear instability analysis of the interrelating system suggests the formation mechanism of honami.