• Journal of Korean Society of Environmental Engineers
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• v.32 no.5
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• pp.427-436
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• 2010

A total of 18 surface sediments within the special conservation zone in the Masan Bay were analyzed to investigate the spatial distribution and polluted pathway of polybrominated diphenyl ehters(PBDEs). Twenty-two PBDE congeners were detected and brominated diphenyl ether-209 (BDE-209) among them was predominant. The concentrations of BDE-209 and ${\Sigma}_{21}$PBDEs (sum of 21 PBDE congeners without BDE-209) ranged from 2.32 to 64.2 ng/g and from 0.72 to 8.24 ng/g, respectively. The spatial distribution of both BDE-209 and ${\Sigma}_{21}$PBDEs showed a negative gradient from the inner to the outer Bay, indicating that the source of PBDEs might be mainly located inside the Bay such as streams and an effluent of wastewater treatment plants. It was seemed likely that the major parameters determining levels of PBDEs in the Masan Bay were the distance discharging from their sources as well as the characteristics and movement of sediments due to the flow of sea water.

• 한국해양학회지
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• v.27 no.4
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• pp.277-289
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• 1992

Kyeonggi Bay, a macrotidal coastal embayment in the Yellow Sea coast of central korea, is fringed by vastly developed tidal flats. About 400 surface sediment samples were collected from the intertidal and subtidal zones of Kyeonggi Bay for a study of the sediment distribution pattern and the surface sediment characteristics of this environment. The kyeonggi Bay surface sediment becomes progressively finer in the shoreward direction, from offshore sand to shoreward silty sand and sandy silt. This shoreward-fining trend is repeated again on the tidal flat and, as a consequence, a grain-size break occurs near the low-water line which separates the intertidal area from the subtidal one. The intertidal and subtidal sediments differ from each other in textural characteristics such as mean grain size and skewness and this can be interpreted to result from differences in hydraulic energy and morphology between the two environments. The mineral and chemical compositions of the Kyeonggi Bay sediments are largely controlled by the sediment grain size. Smectite was nearly absent in the clay mineral assemblage of Kyeonggi Bay sediment. The contents of Co, Cu and Ni were high in the Banweol tidal flat, which suggests a continuous process of accumulation of these metals. the intertidal environment appears to respond rapidly to artificial coastal modifications, the effects of which should be taken into consideration when planning a dam construction or coastal reclamation.

• Journal of The Geomorphological Association of Korea
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• v.18 no.4
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• pp.203-212
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• 2011

The objective of this paper is to identify the present-day surficial sediment distribution patterns of the tidal river, Gongneungcheon, through the grain size and statistical analysis. Four major findings of this study are as follows; First, the composition of sediments over the study area are mainly silt in texture. Second, the surficial sediment distribution reveals that grain size becomes coarser as they approach seawards not only in summer but also in winter. It can be concluded that tidal flows play a significant role, especially in winter, in the distribution of surficial sediments in Gongneungcheon. However, samples obtained in summer were relatively small in mean size and showed better sorting compared to those obtained in winter. Third, the mean sizes of the samples on the transects decrease as the distance from the channel increases. Finally, the artificial structure such as a floodgate affects the distribution of the sediments.

• 한국해양학회지
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• v.27 no.1
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• pp.55-65
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• 1992

Ninety-seven surface sediment samples, collected from the southeastern part of the Yellow Sea, were analyzed for their contents of five metallic elements, including Fe, Mn, Ni, Cu and Pb as well as their grain-size and calcium carbonate content. The result showed a contrasting behaviour among the five metallic elements. with respect to their relationship with the sediment grain0size. contents of nickel and copper demonstrated a fairly linear relationship with the pediment grain-size whereas those of manganese and lead did not. This different behaviour in these metals was interpreted as being the result of the anthropogenic inputs (for Pb) and modification during the early diagenesis (for Mn). The R0mode factor analysis result also confirmed the different behaviour of manganese and lead from that of copper and nickel. Based on this different behaviour in metals the (Mn+Pb)/(Cu+Ni) ratio was suggested as a possible criterion for distinguishing the fine sediments in the study area, which originated from two different source area. China and Korea.

• 한국해양학회지
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• v.29 no.4
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• pp.338-356
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• 1994

Sediment samples from the continental shelf of the South Sea of Korea are analysed to determine the concentration of Al, Fe, Mn, cu, Ni, Zn, Co, Cr and Pb. among these samples, fine-grained sediments were also analysed by a sequential extraction technique to know geochemical forms of the metals in this environments. The total concentration of Al, Fe, Cr, Ni, Cu and Zn in bulk sediments decreased gradually with the increase of distance from the coastal zone. This distribution patterns are well coincide with grain size distribution. However, the patterns of Mn, co and Pb do not follow such and overall distribution. The concentration of Pb, particularly, did not show any features in areal distribution, which may be result from different pathways to the sediments, compared to the other metals. the speculation data show that a considerable amount of Cd, Mn and Co are bounded in the carbonate fraction, accounting for 42.8%, 40.3% and 30.6%, respectively. Cu, Zn, Mn and Fe are largely associated to oxide fraction with proportions of 34.4%, 23.1%, 15.5% and 13.7%, respectively. However, the metals in residual fraction account for more than 50% of the total metal concentration, except for Mn. These observations emphasize that residual fraction in the dominant component controlling the elemental concentration.quartz and glauconite grains.Accordingly,these sediments are interpreted as an extension part of transgressive sand deposit that are widely distributed on the continental shalf floor of southern Yellow Sea.

• Journal of the Korean earth science society
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• v.33 no.6
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• pp.481-496
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• 2012

REE, major and trace elements, and Sr-Nd isotopic ratios of surface sediments around Jeju Island were analyzed for identifying the origin of the sediments. The Chemical Index of Alteration (CIA) between 44.2 to 68.9 (av. 59.4) shows a similarity with the Huanghe sediment. The most sediments found within the study areas show a very similar chondrite-normalized REE pattern that has enriched LREE ($La_{(N)}/Sm_{(N)}$ >3) and small negative Eu anomaly, typically of average shales. The UCC-nornalized REE patterns of the southwestern offshore sediment samples show a very similar pattem with the Changjiang sediment with enriched in most REE and more convex REE pattern than those of the Huanghe and Keum rivers sediments, which indicates that the Changjiang River's suspended sediments have been transported into the western part of Jeju Island. The $^{87}Sr/^{86}Sr$ isotopic ratios vs ${\varepsilon}_{Nd}(0)$ values were thus used as a tracer to discriminate the provenance of sediments in the study area. Based on the discriminated diagram, it clearly showed that most sediments in the western and northwestern part were closely plotted with sediments of the Huanghe River. However, the sediments in the southwestern part near the Changjianf estuary were closely plotted with submerged delta sediments of the Changjiang River. In contrast, the sediment samples of the northeastern part showed discriminative figures from those of the Chinese rivers. It suggests that sediments around Jeju Island must be originated from diverse sources.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.2
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• pp.67-83
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• 2012

In order to evaluate die geochemical characteristics of sediment in a semi-enclosed bay used as shellfish and fish farming area, the concentrations of metallic(V, Cr, Mn, Fe, Co. Ni, Cu, Zn, Ag, Cd, Hg, Ph, As) and non-metallic(P, Se) elements and uranium were measured in the surface sediment samples collected from 19 stations of Gamak Bay in April 2010. Metal contamination status in the sediments were also evaluated using the sediment quality guidelines(SQGs) proposed by the National Oceanic and Atmospheric Administration(NOAA) and the enrichment factor(EF). The concentrations of elements in sediment were mainly controlled by quartz-dilution effect(V, Cr, Fe, Co and Ni), the dilution effect of organic matter(Cd and U), and metal redistribution by the decomposition of organic matter(Mn, Ag, As, and Se). The concentrations of metals, except As and Ni, in sediments from all sampling stations were lower than ERL values of NOAA. Conclusively, the surface sediment of Gamak Bay was slightly polluted with Ni, Ag, Cd, and Cd but was not polluted with other elements on the basis of EF results. Our results suggest that the surface sediment in Gamak Bay is not polluted by metallic elements.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.4
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• pp.372-389
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• 2008

In this study, we formed a detailed grid at the estuary area of the Nakdong and collected the surface sediments. Particle size analysis and comparison with existing data were conducted to investigate the characteristics of seasonal and long-term changes in the sediments. As a result of investigation, the distribution of the sediments showed a great change per season and was greatly influenced by the quantity of outfall discharge at the Nakdong estuary barrier and the incident wave climate. The sandy sediments showed dominant movement toward the front of Jinwoodo west of the estuary area of the Nakdong due to the influence of the ENE wave, the annually-dominant wave. And the muddy sediments showed deposition by being moved toward the deep open sea along with a current. The present conditions of the sediments at the estuary area of the Nakdong showed great differences from the results of previous studies.

• The Korean Journal of Quaternary Research
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• v.4 no.1
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• pp.15-26
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• 1990

Narrow (10-20 km wide) and steep (0.3-$2.4^{\circ}$) continental shelf off the eastern coast of Korea is covered with terrigenous clastic sediments reflecting the Holocene fluctuation of sea level. Surface sediments on the inner shelf consist of muddy sand and sandy mud with some gravels near the coast. However, sand or muddy sand, shell fragments and well rounded gravels occur near the edge of continental shelf at the depth of about 130-l50m. The coarse sediments near the shelf edge seem to be the relict or palimpsest sediments deposited under the nearshore environment during the low-stand or sea level due to so-called the Wisconsinan glaciation. Distribution of recent sediments near the coast and the inner shelf may reflect the affect of waves and currents precluding the deposition of fine sediment near the coast and on the shallow portion of shelf. Eastern Korean Warm Current also nay have played an important role to the transport and distribution of fine sediments from the south.

• Journal of Wetlands Research
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• v.6 no.1
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• pp.167-178
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• 2004

The southern tidal flat of Kanghwa Island is one of the biggest flats on the west coast of Korea. Tide is typically a semidiurnal with maximum range of about 10m. The tidal flat receives large amount of sediments from Han River system. Surface sediments for sedimentary analyses were sampled at 83 stations in the study area in August 2003. The surface sediments consisted of five sedimentary facies. Generally, sandy mud sediments dominated in the southern tidal flat of Kanghwa Island, whereas sand sediments dominated in channel and subtidal zones of the western part of Kanghwa Island. The area of sandy mud sediment extended to eastward tidal flat compared to sedimentary facies in August 1997. Sedimentary facies analysis of three core sediments from the tidal flat to the south of the Kangwha Island revealed three sedimentary facies: trough-cross-bedded sand, laminated silt, and bioturbated silt. Distribution of the facies in the cores suggested that sedimentation rates has been generally high in the margin of main tidal channel, especially in the east of the Donggeum Island. Twelve-and-half-hour anchoring survey was carried out for measurements of hydrodynamic parameters at Yeomha channel near Choji Bridge(K1) and channel near Donggeum Island(K2) in June 2003. Residual flows indicated strong ebb-dominated tidal currents. Depth-integrated net suspended sediment loads for one tidal cycle were seaward movement with 309,217.9kg/m and 128,123.1kg/m at station K1 and K2, respectively. The higher value of net suspended sediment loads at station K1 suggested that lots of suspended sediments from Han River deposited in the eastern part of tidal flat.