Riverbank Stabilization Using Vegetation Cover in the Ferizi River, Khorasan Razavi Province

Document Type : Research

Authors

1 Researcher in Khorasan Agricaltur and Natural Resources Research center

2 Scientific member in Soil Conservation and Watershed Management Institute

3 Expert of Watershed Research Department, Khorasan Razavi Agricaltur and Natural Resources Research and Education center

Abstract

The use of vegetation cover for the sustainable riverbank stabilization is not only economical in ‌most cases, but also ameliorates the landscape. The purpose of this research was to evaluate vegetatative stabilization of the Ferizi River, s erodible banks. Considering that each vegetative form offers a unique type of protection, 8 grass species, short shrub and a tree species were selected for this research. Salix eleganos Scop.,Salix alba L. Elaeagnos angustifolia L. were planted at suitable spacing on the banks. A plot without vegetative protection was established as the control steel pins with specific lengths were driven in to the banks at two rows and three cross sections. The depth of erosion was measured monthly for 4 years by an increase in the length of the pins outside of the river side on transects. The flow data were collected at the hydrometry station. The results indicated that shrub and tree cover performed satisfactorily in stabilizing the riverbank. The erosion depth for the shrub and tree cover was <1% of the control; this was 50% for the grass cover; therefore it was not as effective in erosion control as we had expected. The reason for this poor performance is due to the growth season of these grass species which is not ‌synchronized with flooding season of the Ferizi River. It is interesting to note that the study duration coincided with the 5-year flow regime of the river.

Keywords


Beeson CE, Doyle PF. 1995. Comparison of bank erosion at vegetated and non-vegetated channel bends.  Journal of the American Water Resources Association. 31(6):983–990.
Beismann H, Wilhelmi H, Baillères H, Spatz HC, Bogenrieder A, Speck T. 2000. Brittleness of twig bases in the genus Salix: fracture mechanics and ecological relevance. Journal of Experimental Botany. 51(344): 617–633.
Camporeale C, Perucca E, Ridolfi L, Gurnell AM. 2013. Modeling the interactions between river morphodynamics and riparian vegetation. Reviews of Geophysics. 51(3):379–414.
Cavaillé P, Ducasse L, Breton V, Dommanget F, Tabacchi E, Evette A. 2015. Functional and taxonomic plant diversity for riverbank protection works: Bioengineering techniques close to natural banks and beyond hard engineering. Journal of Environmental Management. 151:65–75.
Chiew YM, Tan SK. 1992. Frictional resistance of overland flow on tropical turfed slope. Journal of Hydraulic Engineering. 118(1):92–97.
Darby SE. 1999. Effect of riparian vegetation on flow resistance and flood potential. Journal of Hydraulic Engineering. 125(5):443–54.
Davoudi MH. 2009. Variation of shear resistance parameters in fine grain soils due to willow roots density. Journal of Range and Watershed Management. 62(2):231–246. (In Persian).
Dhital YP, Tang Q. 2015. Soil bioengineering application for flood hazard minimization in the foothills of Siwaliks, Nepal. Ecological Engineering. 74:458–462.
Donat M. 1995. Bioengineering techniques for streambank restoration. A Review of Central European Practices. Vancouver, BC, Canada: Watershed Restoration Program. Ministry of Environment, Lands and Parks, and Ministry of Forests.
Evette A, Labonne S, Rey F, Liebault F, Jancke O, Girel J. 2009. History of bioengineering techniques for erosion control in rivers in Western Europe. Environmental Management. 43(6):972–984.
Fathi-Maghadam M, Kouwen N. 1997. Nonrigid, nonsubmerged, vegetative roughness on floodplains. Journal of Hydraulic Engineering. 123(1):51–7.
Hosseini A, Shafai-Bajestan M. 2016. Investigating the impact of slope and flow of riverbank on the root system of riparian Trees. J. Sci. & Technol. Agric. & Natur. Resour. Water and Soil Sci. 20(75):101–112. (In Persion).
Kouwen N. Fathi-Moghadam M. 2000. Friction factors for coniferous trees along rivers. Journal of Hydraulic Engineering. 126(10):732–40.
Li MH. Eddleman KE. 2002. Biotechnical engineering as an alternative to traditional engineering methods: A biotechnical streambank stabilization design approach. Landscape and Urban Planning. 60(4):225–42.
Li X, Zhang L, Zhang Z. 2006. Soil bioengineering and the ecological restoration of riverbanks at the Airport Town, Shanghai, China. Ecological Engineering. 26(3):304–14.
Noarayanan L, Murali K, Sundar V. 2012. Performance of flexible emergent vegetation in staggered configuration as a mitigation measure for extreme coastal disasters. Natural Hazards. 62(2):531–50.
Samani JM. Kouwen N. 2002. Stability and erosion in grassed channels. Journal of Hydraulic Engineering. 128(1):40–5.
Shafai- Bajestan M, Salimi Golsheykhi M. 2002. Determination of the effect of root of puddah and gaz trees on shear resistance of Karun beach in place. Journal of Agricultural Science and Technology, and Natural Resources. 6(4):27–40. (In Persian).
Sotir RB, Difini JT, McKown AF. 1998. Partnering geosynthetics and vegetation foreErosion control. InGeosynthetics in Foundation Reinforcement and Erosion Control Systems. ASCE.pp. 92–102.
Tominaga A, Nagao M, Nezu I. 1999. Flow structure and momentum transport processes in curved open-channels with vegetation. InProc. 28th IAHR Congress, Technical University of Graz, Austria. Institute for Hydraulics and Hydrology.
Truong P, Van TT, Pinners E. 2008. Vetiver system applications technical reference manual. The Vetiver Network International, 89.
Velayati S, Ghauor H, Shafaa P. 2004. Investigation of the hydrologic regime of the Frizi River (the Kashafrod catchment sub-basin) and its role in feeding the aquifer of Mashhad Plain. Geography and Development Magazine. Spring and Summer. 2004:47 ASCE. 72. (In Persian).
Wilson CA, Sellin RH. 1999. A field investigation of vegetation effects in a doubly meandering compound channel. InIAHR Congress, Graz. 6 p.
Zhong RH, He XB, Bao YH, Tang Q, Gao JZ, Yan DD, Wang MF, Li Y. 2016. Estimation of soil reinforcement by the roots of four post-dam prevailing grass species in the riparian zone of Three Gorges Reservoir, China. Journal of Mountain Science. 13(3):508 ASCE. 21.