A three-dimensional modeling of the morphological change in the Liaodong Bay

Abstract

The morphology in the Liaodong Bay has undergone a marked change over the past decades due to the cutoff of nearby rivers. The fine sediment of the bay consists of both non-cohesive and cohesive fractions with relatively small particles over the seabed. Thus, a three-dimensional morphodynamic model accounting for non-cohesive and cohesive fractions is established to investigate the morphological change without sediment input from nearby rivers. A representative wave is chosen to compute the wave distribution in the Liaodong Bay and depth-dependent wave radiation stresses are employed by the hydrodynamic model. The advection-diffusion equation is used to simulate the fine sediment transport under the representative wave and tidal currents. The erosion flux of non-cohesive and cohesive sediment is taken into account. The simulated results of tidal level, velocities, directions, and sediment concentrations are in agreement with the measured data. The results demonstrate that the present model, which takes the erosion flux of both non-cohesive and cohesive fractions into account, gives more reasonable values than when accounting for cohesive sediment alone. When the three-dimensional morphodynamic model is applied to predict morphological change over the course of a year, the deposition is shown to be relatively small and the range of the erosion is increased compared to previous results of sediment input from the river. It can be concluded that the erosion in the Liaodong Bay is increasing due to the cutoff of the river, and that morphological evolution must be taken into account if any type of coastal construction plans are to be carried out over the seabed.

Keywords

fine sediment / three-dimensional model / morphological change / representative wave

References

[1] Ariathurai R, Arulanandan K (1978). Erosion rates of cohesive soils. J Hydraul Div, 104(2): 279–283

[2] Chao X B, Jia Y F, Shields D Jr, Wang S, Cooper C M (2008). Three-dimensional numerical modeling of cohesive sediment transport and wind wave impact in a shallow oxbow lake. Adv Water Resour, 31(7): 1004–1014

[3] Chen C, Liu H, Beardsley R C (2003). An unstructured grid, finite-volume, three-dimensional, primitive equations ocean model: application to coastal ocean and estuaries. J Atmos Ocean Technol, 20(1): 159–186

[4] Chesher T J, Miles G V (1992). The concept of a single representative wave for use in numerical-models of long-term sediment transport predictions. In: Liu S Q, ed. Hydraulic and Environmental Modeling: Coastal Waters. Brookfield: Ashgate, 371–380

[5] Chonwattana S, Weesakul S, Vongvisessomjai S (2005). 3D modeling of morphological changes using representative waves. Coast Eng J, 47(4): 205–229

[6] de Vriend H J, Capobianco M, Chesher T, de Swart H E, Latteux B, Stive M J F (1993). Approaches to long-term modeling of coastal morphology—A review. Coast Eng, 21(1–3): 225–269

[7] Du P J, Ding P X, Hu K L (2010). Simulation of three-dimensional cohesive sediment transport in Hangzhou Bay, China. Acta Oceanol Sin, 29(2): 98–106

[8] Elder J W (1959). The dispersion of marked fluid in turbulent shear flow. J Fluid Mech, 5(4): 544–560

[9] Fu W, Li G, Liu G (1994). The hydraulic geomorphological feature and the change of beach face in Jinzhou Bay. Geographical Research, 13(2): 11–19 (in Chinese)

[10] Holthuijsen L H, Booij N, Ris R C (2011). SWAN user manual (version 40.85). Delft University of Technology Faculty of Civil Engineering and Geoscience Environmental Fluid Mechanics Section

[11] Krone R B (1962). Flume studies of the transport of sediment in estuarial shoaling processes. Final report. Hydraulic Engineering Laboratory and Sanitary Engineering Research Laboratory, Berkeley: University of California: 110

[12] Latteux B (1995). Techniques for long-term morphological simulation under tidal action. Mar Geol, 126(1–4): 129–141

[13] Le Hir P, Cayocca F, Waeles B (2011). Dynamics of sand and mud mixtures: a multiprocess-based modelling strategy. Cont Shelf Res, 31(10): S135–S149

[14] Lesser G R, Roelvink J A, van Kester J, Stelling G S (2004). Development and validation of a three-dimensional morphological model. Coast Eng, 51(8–9): 883–915

[15] Lin B L, Falconer R A (1996). Numerical modelling of three-dimensional suspended sediment for estuarine and coastal waters. J Hydraul Res, 34(4): 435–456

[16] Lopes J F, Dias J M, Dekeyser I (2006). Numerical modelling of cohesive sediments transport in the Ria de Aveiro lagoon, Portugal. J Hydrol (Amst), 319(1–4): 176–198

[17] Mellor G L (2008). The depth-dependent current and wave interaction equations: a revision. J Phys Oceanogr, 38(11): 2587–2596

[18] Miao F, Li S, Li G, Fu W, He B (1996). Suspended sediment transport tendency and the study of sedimentary divisions in the northern Liaodong Bay. Acta Sedimentologica Sinica, 14(4): 114–121 (in Chinese)

[19] Pang C, Yu W (2013). Spatial modes of suspended sediment concentration in surface water in Bohai Sea and their temporal variations. Adv Water Sci, 24(5): 722–727 (in Chinese)

[20] Pinto L, Fortunato A B, Zhang Y, Oliveira A, Sancho F (2012). Development and validation of a three-dimensional morphodynamic modelling system for non-cohesive sediments. Ocean Model, 57 – 58: 1–14

[21] Roelvink J A (2006). Coastal morphodynamic evolution techniques. Coast Eng, 53(2–3): 277–287

[22] Soulsby R L, Clarke S (2005). Bed shear-stresses under combined waves and currents on smooth and rough beds. HR Wallingford, Report TR137

[23] Steijn R C, Hartsuiker G (1992). Morphodynamic response of a tidal inlet after a reduction in basin area. Delft Hydraulics, Coastal Genesis Report, 22–24

[24] van Rijn L C (1984). Sediment transport. 2. Suspended-load transport. J Hydraul Eng, 110(11): 1613–1641

[25] Waeles B, Le Hir P, Lesueur P, Delsinne N (2007). Modelling sand/mud transport and morphodynamics in the seine river mouth (France): an attempt using a process-based approach. Hydrobiologia, 588(1): 69–82

[26] Wang W, Ma H, Yin X, Miao F (2010). Grades and distribution of coastal erosion and siltation in Liaoning Province. Mar Sci, 35(8): 65–68 (in Chinese)

[27] Wang Y and He B (1993). Modern erosion and accumulation trends of the north shallow region of Liaodong Bay. Transactions of Oceanology and Limnology, 15(4): 13–19 (in Chinese)

[28] Warner J C, Sherwood C R, Signell R P, Harris C K, Arango H G (2008). Development of a three-dimensional, regional, coupled wave, current, and sediment-transport model. Comput Geosci, 34(10): 1284–1306

[29] Xie M X, Zhang W, Guo W J (2010). A validation concept for cohesive sediment transport model and application on Lianyungang harbor, China. Coast Eng, 57(6): 585–596

[30] Zhang M, Feng X, Hao Y (2011). Quantitative remote sensing study on spatio-temporal variation of suspended sediment in north Liaodong Bay. J Sediment Res, 56(4): 15–21 (in Chinese)

Acknowledgements

The authors appreciate being provided with the source code of the circulation model FVCOM to develop the current work and would thank Jeffrey Steynor and Tsung-Chow Su for revising the original paper. Comments from the anonymous reviewers are acknowledged for improving the manuscript.

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg