Roles of Aquatic Plants on Erosion Relief of Stream Bed

Authors: Jin-Hong Kim

Abstract:

Roles of the vegetation to mitigate the erosion of the stream bed or to facilitate the deposition of the fine sediments by the species of the aquatic plants were presented. Field investigation on the estimation of the change of the bed level and the estimation of the flow characteristics were performed. The results showed that Phragmites japonica has the mitigation function of 0.3m-0.4m of the erosion in the range of higher than 1.0m/s of flow velocity at the vegetated region. Phragmites communis has the mitigation function of 0.2m-0.3m of the erosion in the range of higher than 0.7m/s of flow velocity at the vegetated region. Salix gracilistyla has greater role than Phragmites japonica and Phragmites communis to sustain the stable channel. It has the mitigation function of 0.4m-0.5m of the erosion in the range of higher than 1.4m/s of flow velocity. Miscanthus sacchariflorus has a weak role compared with that of Phragmites japonica and Salix gracilistyla, but it has still function for sustaining the stable bed. From these results, the vegetation has effective roles to mitigate the erosion or to facilitate the deposition of the stream bed.

Keywords: Aquatic plants, Phragmites japonica, Phragmites communis, Miscanthus sacchariflorus, Salix gracilistyla.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1106989

References:

[1] J. H. Kim, “Hydraulic effects on vegetation impact by flood flow in urban streams.” Proceedings of the 8th International Symposium on New Technologies for Urban Safety of Mega Cities in Asia, 2009, pp. 72-80.
[2] M. Miyazaki, S. Honda, H. Kawase, N. Awamura, and M. Kitoh, “A study concerning the river hydraulic examination method which considers the dynamic characteristics of reed community at the time of the flood.” River Technology Journal, Vol. 9, 2003, pp. 79-84. (in Japanese).
[3] Y. Shimizu, K. Osada, and M. H. Kim, “Study on the flood disturbance and the destruction of vegetation in a degraded gravel-bed river.” River Technology Journal, Vol. 9, 2009, pp. 377-382. (in Japanese).
[4] N. Tamai, N. Mizuno, and S. Nakamura, Environmental River Engineering, University of Tokyo, Tokyo, 2009, pp. 125-128. (in Japanese).
[5] J. H. Kim, “Effects on Erosion/Deposition of Stream Bed by Aquatic Plants”, Asia Oceania Geophysical Society, Singapore, 2009, pp. 12-16.
[6] National Rivers Authority. River Corridors Survey Methods and Procedures, 1992, London.
[7] National Institute of Environmental Research. Survey and Evaluation of Aquatic Ecosystem Health in the Nakdong River, Ministry of Environment, Seoul, 1998 pp. 224-226. (in Korean).