Abstract
A dynamic model for predicting the long term change of vegetated area in river was developed when the flood does not change the morphology of the gravel bar. In this simulation model, the expansion, destruction due to floods and regeneration of the plants were considered. Change of vegetation succession speed was included in relation to the tendency of fine sand deposition due to floods. For elucidating the characteristics of deposition of fine sand due to floods, deposition situation after 2007 and 2012 flood events were investigated on the two gravel bars in the middle stream of Arakawa River.
The simulation model was developed on a gravel bar located near Kumagaya Ohashi (KU) and applied to a gravel bar located near Arakawa Ohashi (AR) for validating the change of vegetated area from 2000 to 2012. This model expressed the situation of vegetated area in 2012 within the reasonable limit. Especially, this model can be found to describe not only the expansion location of each vegetation but also the vegetated area of each vegetation by considering change of vegetation succession due to deposition of fine sand by floods.
