Abstract
Over the past three decades, dike constructions along the shores and dredging activities for navigation purposes have caused significant sedimentologic/morphologic modifications of a mid-channel bar situated in the tidal seaway of outer Asan Bay, Korea, as shown by a comparison of two sediment datasets collected in the channel and over the bar in 1977 and 2008. In addition, three hydrographic charts published in 1976, 1989, and 2006 were analyzed using GIS to estimate sand volume budgets and any bar migration. The bar is currently about 15 km long and 2–5 km wide, with a relief of 15 m. It is elongated in the tidal flow direction, but asymmetric in cross section. Chart analyses reveal a dramatic reduction in size and volume over the study period. An approximate 19% net loss in total sediment volume was calculated between 1976 and 1989. Since then, a net gain of about 7% has been estimated. The surface areas between selected depth contours reveal a similar pattern, i.e., substantial shrinking until 1989, followed by slight expansion up to 2006. Comparing selected textural parameters (mean grain size, sorting) of a 2008 sediment sampling campaign with those of a 1977 survey, it was found that mean grain sizes have decreased by as much as 1-phi interval, and that the sediments have become more poorly sorted in the vicinity of the bar over the 30-year study period, probably due to a sudden decrease in tidal energy flux after completion of the adjacent dikes. A particular feature is the temporary response of the bar to man-made impacts, characterized by substantial shrinking along its southwestern flank, and slight expansion along its northeastern flank. The observed changes in bar morphology can plausibly be explained by a sudden decrease in sediment supply resulting from a reduction in tidal prism in the wake of diking. The bar initially shrunk, but since 1989 has begun to gradually recover. To compensate the deficit, the bar has lowered its base level by scouring troughs along both flanks.
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References
Ashley G (1990) Classification of large-scale subaqueous bedforms: a new look at an old problem. J Sediment Petrol 60:160–172
Bartholom ä A, Ernstsen VB, Flemming BW, Bartholdy J (2004) Bedform dynamics and net sediment transport paths over a flood-ebb tidal cycle in the Gr ådyb channel (Denmark), determined by high-resolution multi-beam echosounding. Danish J Geogr 104:45–55
Biegel E, Hoekstra P (1995) Morphological response characteristics of the Zoutkamperlaag, Frisian inlet (The Netherlands), to a sudden reduction in basin area. In: Flemming BW, Bartholom ä A (eds) Signatures in modern and ancient sediments. IAS Spec Publ 24:85–99
Carver RE (1971) Procedures in sedimentary petrology. Wiley, New York
Cheung KF, Gerritsen F, Cleveringa J (2007) Morphodynamics and sand bypassing at Ameland Inlet, The Netherlands. J Coastal Res 23:106–118
Choi JY, Choi JH, Kim SY (1999) Granulometric analysis of sediment: preliminary results for inter-lab calibration (in Korean, with English abstract). J Korean Soc Oceanogr 4:246–253
Dalrymple RW, Rhodes RN (1995) Estuarine dunes and bars. In: Perillo GME (ed) Geomorphology and sedimentology of estuaries. Elsevier, Amsterdam, pp 359–422
Eo D, Choi KW (1999) Changes in sedimentary environment and coastal morphology due to sea dike construction (in Korean, with English summary). Korea Rural Corp Res Rep no 99-05-18
Ernstsen VB, Noormets R, Hebbeln D, Bartholom ä A, Flemming BW (2006) Precision of high-resolution multibeam echo sounding coupled with high-accuracy positioning in a shallow water coastal environment. In: Bartholom ä A, Winter C (eds) Coastal dynamics and human impact: south-eastern North Sea.
Geo-Mar Lett SI 26(3):141–149. doi:10.1007/s00367-006-0025-3
Flemming BW (2000) On the dimensional adjustment of subaqueous dunes in response to changing flow conditions: a conceptual process model. In: Trentesaux A, Garlan T (eds) Proc Int Worksh Marine Sandwave Dynamics, University of Lille, pp 61–67
Flemming BW, Davis RA Jr (1994) Holocene evolution, morphodynamics and sedimentology of the Spiekeroog barrier island system (southern North Sea). Senckenberg marit 24:117–155
Folk RL (1966) A review of grain-size parameters. Sedimentology 6:73–93
Folk RL, Ward WC (1957) Brazos River bar: a study in the significance of grain size parameters. J Sediment Petrol 27:3–26
Hayes MO (1979) Barrier island morphology as a function of tidal and wave regime. In: Leatherman SP (ed) Barrier islands. Academic, New York, pp 1–27
Kim SW, Lee YO, Chang JH (1977) Marine geological investigation of the Asan Bay, west coast of Korea (in Korean, with English abstract). Rep Geosci Mineral Resources 2:163–244
KRC (1996) Land reclamation in Korea (in Korean). Korea Rural Corporation, Euwang
Kr ögel F, Flemming BW (1998) Evidence for temperature-adjusted sediment distributions in the backbarrier tidal flats of the East Frisian Wadden Sea (southern North Sea). In: Alexander CR, Davis RA, Henry VJ (eds) Tidalites. Processes & products. SEPM Spec Publ 61:31–41
Kr üger JC, Healy T (2006) Mapping the morphology of a dredged tidal ebb delta, Tauranga Harbour, New Zealand. J Coastal Res 22:720–727
Lamour MR, Angulo RJ, Soares CR (2007) Bathymetrical evolution of critical shoaling sectors on Galheta Channel, navigable access to Parangu á Bay, Brazil. J Coastal Res 23:49–58
Mimura N (2008) Asia-Pacific coasts and their management: states of environment. Springer, Dordrecht
Molinaroli E, Guerzoni S, Sarretta A, Masiol M, Pistolato M (2009) Thirty-year changes (1970–2000) in bathymetry and sediment texture recorded in the Lagoon of Venice sub-basins, Italy. Mar Geol 258:115–125
MOMAF (2007) Annual report on maritime and fisheries statistics (in Korean). Ministry of Maritime Affairs and Fisheries, Seoul
NORI (2003) Tidal current charts (Incheon Hang and approaches). National Oceanographic Research Institute, Incheon, Publ no 634
NORI (2008) Jungangcheontoe sand bar in the macrotidal channel of outer Asan Bay, Korea (in Korean). National Oceanographic Research Institute, Incheon, Res Rep no 11-161123-000017-01
Oost AP (1995) Sedimentological implications of morphodynamic changes in the ebb-tidal delta, the inlet and the drainage basin of the Zoutkamperlaag tidal inlet (Dutch Wadden Sea), induced by a sudden decrease in the tidal prism. In: Flemming BW, Bartholom ä A (eds) Signatures in modern and ancient sediments. IAS Spec Publ 24:85–99
Oost AP, de Haas H (1992) Het Friesche Zeegat, morfologisch-sedimentologische veranderingen in de periode 1970–1987, een getijde inlet systeem uit evenwicht. Kustgenese 1(1/2):1–68
Park M-J (2000) Modeling of sediment transport and sand bank formation in a macrotidal sea. J Korean Soc Oceanogr 35:1–10
Park SC, Yoo DG (1997) Bedform distribution and sand transport trend on a subtidal sand ridge in a macrotidal bay, west coast of Korea. J Korean Soc Oceanogr 32:181–190
Pilkey OH, Dixon KL (1996) The Corps and the shore. Island, Washington, DC
Reineck H-E, Singh IB (1980) Depositional sedimentary environments with reference to terrigenous clastics. Springer, Berlin
Wells JT, Adams CE Jr, Park YA, Frankenberg EW (1990) Morphology, sedimentology and tidal channel processes on a high-tide-range mudflat, west coast of South Korea. Mar Geol 95:111–130
Wunderlich F (1978) Deposition of mud in the giant ripples of the inner Jade, German Bight, North Sea. Senckenberg marit 10:257–267
Zviely D, Kit E, Rosen B, Galili E, Klein M (2009) Shoreline migration and beach-nearshore sand balance over the last 200 years in Haifa Bay (SE Mediterranean). Geo-Mar Lett 29:93–110. doi:10.1007/s00367-008-0126-2
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Chang, T.S., Kim, SP., Yoo, D.G. et al. A large mid-channel sand bar in the macrotidal seaway of outer Asan Bay, Korea: 30 years of morphologic response to anthropogenic impacts. Geo-Mar Lett 30, 15–22 (2010). https://doi.org/10.1007/s00367-009-0146-6
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DOI: https://doi.org/10.1007/s00367-009-0146-6