Author(s): Hitoshi MIYAMOTO, Kengo Kataoka, Kataoka Hiroshi

Linked Author(s): Hitoshi MIYAMOTO

Keywords: Riparian vegetation management; Stochastic process model; Flood impact; Plant physiology; And channel geomorphology;

Abstract: This paper examined and compared the tendency of vegetation overgrowth in several river channels of two river basins by using a vegetation dynamics model. The model employed a stochastic evaluation method for examining vegetation population states in a river cross section using an integrated model with Monte Carlo simulation. The integrated model consists of four processes as sub-models, i.e., vegetation population dynamics, stochastic flow discharge, stream hydraulics, and channel geomorphology. The two river basins examined in this paper were Kako River and Takatsu River in Japan, where many parts of the river channels have been well-vegetated states during recent several decades. The optimal parameters of the vegetation dynamics model were determined in terms of flood impacts and plant physiology for applying it to the tendency analysis of several river channels in the two river basins. The results indicated stronger flood impact and weaker plant physiology of Takatsu River, resulting in that the tendency of vegetation overgrowth would be stronger in the Kako River channels compared to the Takatsu River channels. It also showed that the well-vegetated channels in both river basins would have larger width ratios of the low and high water channels. The integrated stochastic evaluation approach used in this paper could constitute an effective method for evaluating vegetation overgrowth tendency in river channels for a long period of time.

DOI: https://doi.org/10.3850/38WC092019-1233

Year: 2019