VEGETATION EFFECTS IN BRAIDED RIVERS WITH ERODIBLE BANKS

Laboratory experiments were carried out to elucidate the influence of riparian vegetation on braided rivers with unconstrained banks. One run for barided river without vegetation from initial straight channel and two kinds of runs for the river with vegetation were conducted. For the vegetated braided river alfalfa seed was introduced to the channel by controlling the density. In this study, flow characteristics and channel evolution to explain vegetation effects in braided river were investigated. Especially in morphological behavior, a primary channel was developed to a high meandering channel and bifurcated to two channels due to vegetation on the bed and banks. And numerical model is applied to investigate the effect of vegetation in braided river with and without vegetation and the results are discussed.