Experimental analysis of meandering channel development processes with floodplain vegetation

Chang-Lae Jang

doi:10.3741/JKWRA.2023.56.12.895

All Issue

2023 Vol.56, Issue 12 Preview Page Next Page

Research Article

Experimental analysis of meandering channel development processes with floodplain vegetation 홍수터 식생에 의한 저수로 사행 발달과정 실험적 분석

31 December 2023. pp. 895-903

PDF XML

Abstract

This study investigates the impact of riparian vegetation in the floodplain on channel stability, changes in bend curvature, and meandering channel migration. In channels with riparian vegetation, over time, meander width remains relatively constant, but selective bank erosion leads to meander development and downstream movement. During this process, bank erosion and changes in the riverbed are not significant, and the channel maintains relatively constant conditions with reduced sediment discharge and minimal variability. As the density of vegetation increases, bank erosion rates decrease. The erosion rates along the riverbanks increase with the density of vegetation on the floodplain, thus affecting the development of meanders. This factor notably contributes to enhancing riverbank stability and influencing channel changes through floodplain vegetation. Bank erosion rates and dimensionless bend curvature are greatest when there is no riparian vegetation but decrease in conditions with vegetation. Furthermore, the relationship between lateral migration rate and dimensionless bend curvature is similar to that of bank erosion rates. Therefore, riparian vegetation enhances channel stability, influencing bank erosion, meander curvature, and meander migration.

Keywords

Vegetation

Bank erosion

Meandering

Bend curvature

Meander migration

본 연구에서는 실내실험을 수행하여 홍수터 식생에 의한 하안의 안정성, 만곡부의 곡률 변화, 사행의 발달과 이동을 정량적으로 분석하였다. 홍수터에 식생이 있는 하도는 시간이 증가하면서 사행의 하폭이 일정하게 유지하지만, 선택적인 하안침식에 의해 사행이 발달하고 하류로 이동하였다. 이러한 과정에서 하안침식과 사주의 변화가 크지 않으며, 저수로가 일정하게 유지되면서 유사유출량은 감소하고 변동성이 거의 없이 일정하게 유지되고 있다. 식생의 밀도가 증가함에 따라, 하안침식률이 감소하였다. 식생의 밀도가 증가함에 따라 하안침식률이 감소하였고, 사행의 발달에 영향을 주었다. 이는 홍수터 식생이 하안의 안정성을 증가시키고, 하도의 평면변화에 영향을 미치는 주요 인자 중의 하나임을 의미한다. 하안침식률과 무차원 곡률반경은 홍수터에 식생이 없는 조건에서 가장 크고, 식생이 있는 조건에서는 작다. 또한 상대 측방이동률과 무차원 곡률반경도 하안침식률과의 관계가 유사하는 특성을 보였다. 따라서 홍수터 식생은 하도의 안정성을 증가시켜서 하안침식과 사행의 발달뿐만 아니라, 사행의 곡률변화와 이동에 영향을 준다.

키워드

하도식생

하안침식

사행

사행곡률

사행 이동

References

Braudrick, C.A., Dietrich, W.E., Leverich, G.T., and Sklar, L.S., (2009). "Experimental evidence for the conditions necessary to sustain meandering in coarse bedded rivers." Proceedings of the National Academy of Sciences, Vol. 106, No. 40, pp. 16936-16941. doi: 10.1073/pnas.0909417106. 10.1073/pnas.090941710619805077PMC2761352

Camporeale, C., Perona, P., Porporato, A., and Ridolfi, L. (2005). "On the long-term behavior of meandering rivers." Water Resources Research, Vol. 41, No, 12, W12403. doi: 10.1029/2005WR004109. 10.1029/2005WR004109

Colombini, M., Seminara, G., and Tubino, M. (1987). "Finite-amplitude alternate bars." Journal of Fluid Mechanics, Vol. 181, pp. 213-232. 10.1017/S0022112087002064

Defina, A.(2003). "Numerical experiments on bar growth." Water Resources Research, Vol. 39, No. 4, 1092. 10.1029/2002WR001455

Fujita, Y., and Muramoto, Y. (1982). "Experimental study on stream channel processes in alluvial rivers." Bulletin of the Disaster Prevention Research Institute, Kyoto University, Vol. 35, No. 314, pp. 55-86.

Hoey, T.B., and Sutherland, A.J. (1991). "Channel morphology and bedload pulses in braided rivers: A laboratory study." Earth Surface Processes and Landforms, Vol. 16, pp. 447-462. 10.1002/esp.3290160506

Ielpi, A., Lapotre, M,G., Gibling, M.R., and Boyce, K. (2022). "The impact of vegetation on meandering rivers." Nature Reviews Earth & Environment, Vol. 3, pp. 165-178. doi: 10.1038/s43017-021-00249-6. 10.1038/s43017-021-00249-6

Jang, C.-L. (2013). "Experimental analysis of the morphological changes of the vegetated channels." Journal of Korea Water Resources Association, KWRA, Vol. 46, No. 9, pp. 909-919. 10.3741/JKWRA.2013.46.9.909

Jang, C.-L. (2022). "Experimental analysis on the morphologic changes and adaption of the channels to floodplain vegetation." Journal of Korea Water Resources Association, Vol. 55, No. 10. pp. 801-810. doi: 10.3741/JKWRA.2022.55.10.801 10.3741/JKWRA.2022.55.10.801

Jang, C.-L., and Shimizu, Y. (2005). "Numerical simulations of the behavior of alternate bars with different bank strengths." Journal of Hydraulic Research, Vol. 43, No. 6, pp. 595-611. 10.1080/00221680509500380

Julien, P.Y. (2002). River engineering. Cambrige Univeristy Press, Cambridge, pp. 187-190.

Kleinhans, M.G. (2010). "Sorting out river channel patterns." Prog. Phys. Geogr., 34, 287-326, doi: 10.1177/0309133310365300. 10.1177/0309133310365300

Kleinhans, M.G., de Vries, B.M.L., Braat, L., and Van Oorschot, M. (2018). "Living landscapes: Muddy and vegetated floodplain effects on fluvial pattern in an incised river." Earth Surface Processes and Landforms, Vol. 43, No. 14, pp. 2948-2963. doi: 10.1002/esp.4437. 10.1002/esp.443730555199PMC6282967

Leopold, L.B., and Wolman, M.G. (1957). River channel patterns: Braided, meandering, and straight. US Geological Survey Professional Paper 282-B, US Geological Survey, Washington. D.C., U.S. 10.3133/pp282B

Schumm, S.A. (1985). "Patterns of alluvial rivers." Annual Review of Earth and Planetary Sciences, Vol. 13, pp. 5-27. 10.1146/annurev.ea.13.050185.000253

Thorne, C.D., and Furbish, D.J. (1995). "Influences of coarse bank roughness on flow within a sharply curved river bend." Geomorphology, Vol. 12, pp. 241-257. 10.1016/0169-555X(95)00007-R

van Dijk, W.M., Teske, R., van de Lageweg, W.I., and Kleinhans, M.G. (2013). "Effects of vegetation distribution on experimental river channel dynamics." Water Resources Research, Vol. 49, No. 11, pp. 7558-7574. doi: 10.1002/2013WR013574. 10.1002/2013WR013574

van Dijk, W.M., van de Lageweg, W.I., and Kleinhans, M.G. (2012). "Experimental meandering river with chute cutoffs." Journal of Geophysical Research, Vol. 117, F03023. doi: 10.1029/2011JF002314. 10.1029/2011JF002314

Vargas-Luna, A., Duró, G., Crosato, A., and Uijttewaal, W. (2019). "Morphological adaptation of river channels to vegetation establishment: A laboratory study." Journal of Geophysical Research: Earth Surface, Vol. 124, pp. 1981-1995. doi: 10.1029/2018JF004878. 10.1029/2018JF004878

Zhu, L., Chen, D., Hassan, M.A., and Venditti, J.G. (2022). "The influence of riparian vegetation on the sinuosity and lateral stability of meandering channels." Geophysical Research Letters, Vol. 49, No. 2, e2021GL096346. doi: 10.1029/2021GL096346. 10.1029/2021GL096346

Information

Publisher :KOREA WATER RESOURECES ASSOCIATION
Publisher(Ko) :한국수자원학회
Journal Title :Journal of Korea Water Resources Association
Journal Title(Ko) :한국수자원학회 논문집
Volume : 56
No :12
Pages :895-903
Received Date : 2023-10-29
Revised Date : 2023-11-24
Accepted Date : 2023-11-24
DOI :https://doi.org/10.3741/JKWRA.2023.56.12.895

Journal of Korea Water Resources Association ISSN:2799-8746(Print) 2799-8754(Online) 한국수자원학회 논문집

All Issue