河原における植生の種子漂着場に関する研究

抄録

In order to understand the mechanism of the settlement of vegetation seed on a gravel bar, field measurements and hydraulic experiment were conducted. Several gravel bars that have different shape were selected as study sites, and morphology, substrate and vegetation distribution were investigated. After that, the model of each gravel bar was created and installed in the experimental flume. Then fine powder was dropped and the position of settlement was recorded. Consequently following characteristics are clarified. 1. Floating seed tends to gather at the shore of the retarded water area. 2. Gradual attenuation of the flood induces more seed to attach the gravel bar than rapid attenuation. 3. Even if vegetation seeds attach on the gravel bar, thick surface layer of gravel prevent them from germination.