• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2003.08a
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• pp.170-178
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• 2003

과거 경제도약기에는 개발을 위한 자연훼손의 문제점이 크게 부각되지 않았으며, 연안개발의 경우도 마찬가지이었다. 그러나 선진국들은 1970년대부터 자국의 자연환경보호를 위한 구체적인 행동을 취하기 시작하였으며, 1992년 우리나라를 비롯한 178개국이 참석한 유엔환경개발회의 (UNCED)에서 '환경이 감당할 수 있는 범위 내에서의 지속 가능한 개발, ESSD(Environmentally Sound and Sustainable Development)'를 위한 '의 제 21 (Agenda21)' 이 채택되었다. (중략)

• The Korean Journal of Quaternary Research
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• v.15 no.1
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• pp.29-35
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• 2001

The coastal deposits along Moonamni, Kangwon Province, Korea have been investigated by using deeply cored sediments(down to the basement rocks : Pre-Cambrian metamorphic rocks and granitic rocks) in order to understand and propose the late Quaternary stratigraphy and related major unconformities. Three major stratigraphic -depositional units are proposed. The neolithic cultural sites in the Moonamni area are considered as middle Holocene coastal dunes, which were developed due to active supply of beach sands from Unit I(Holocene transgressive deposit). Such coastal dune sediments are characteristic in the upper part of Unit I(Holocene in age). So far, Unit II and Unit III are considered as continental deposits, such as fluvial-swamp and alluvial deposit, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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• pp.777-787
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• 2017

Organic enrichment and pollution was investigated in surface sediments from Jinhae Bay and Geoje-Hansan Bay of Korea, which contain the largest oyster farms in Korean coastal areas. Geochemical indicators (chemical oxygen demand, total organic carbon, ignition loss, and acid volatile sulfide) in sediments, ammonium and nitrate in pore water, and bioluminescence inhibition test for sediment extracts were analyzed. Temporal changes of organic enrichment were also investigated using sediment core samples from Geoje-Hansan Bay. The level of organic pollution in sediments from Jinhae Bay was significantly greater than that of sediments from Geoje-Hansan Bay. Compared with other sites, Jinhae Bay was one of the most polluted coastal areas of Korea. The levels of geochemical indicators in May were comparable to, or higher than, in August. Ammonium concentrations in pore water were two orders of magnitudes greater than the nitrate concentrations, suggesting that the bays are reducing environments. The concentrations of total organic carbon in core sediment samples from shellfish-farming areas increased significantly from 2000 to the present year, and it seems to be associated with increases in anthropogenic activities.

• 한국해양학회지
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• v.28 no.4
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• pp.259-271
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• 1993

The distributions of bottom sediments and the depositional processes on the continental shelves of Korean Seas are interpreted. Generally the continental shelf sediments can be classified into the sand-facies and mud-facies, showing the typical bimodal size distributions Most of the sandy and gravelly sediments on the outer shelf floor are interpreted as "relict" sediments that were deposited during the last glacial times when the sea level was lower than the present. On the other hand the muddy sediments on the inner shelf area are interpreted as "recent" sediments that are deposited under the present environment conditions. It is understood that most of the fine materials cannot escape the inner shelf area due to the strong tidal and coastal fronts, and are transported eastward from the West Sea along the southern coast of Korean Peninsula. The dark-colored muddy sediments in the Hupo Basin of the East Sea are, however, considered to be "relict" sediments. In the midshelf area fine materials are mixed with the relict coarse sediments, and some of the relict sediments are continuously reworked under the present environmental conditions forming the "palimpsest" sediments.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.18 no.3
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• pp.179-188
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• 2006

The purpose of this study is to quantitatively estimate the settling and erosional properties for cohesive sediments in Shihwa lake. Settling tests are conducted by multi-depth method using a specially designed 1.8 m tall settling column, and erosion tests are conducted with annular flume under the uniform bed condition. As result of settling tests, it is confirmed that the settling velocity of the cohesive sediments has the range of $0.002 for suspended sediments concentration of 0.1$0.19{\sim}0.55N/m^{2}$ for bed shear stress of $1.14{\sim}1.32g/cm^{3}$, and the erosion rate coefficient decreases with logarithmic function in a range of $18.4{\sim}3.9mg/cm^{2}{\cdot}hr$ with increase of bed shear stress.

• Journal of the korean society of oceanography
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• v.32 no.3
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• pp.103-111
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• 1997

Biogeochemical cycling of organic carbon is quantitatively partitioned in terms of 1) flux to the ocean bottom, 2) benthic utilization at or near the sediment-water interface, 3) remineralization and 4) burial within sediments, by making an independent determination for each component process from a single coastal site in Kwangyang Bay. The partitioning suggests that the benthic utilization at or near the sediment-water interface is the major mode of organic carbon cycling at the site. The benthic utilization takes 61.8% (441.6 gCm$^{-2}$ yr $^{-1}$) of the total near-bottem organic carbon flux, 714.6 gCm $^{-2}$yr$^{-1}$, and far exceeds the remineralization of organic carbon within the sediments which amounts only to 6% (41.24 gCm$^{-2}$yr$^{-1}$) of the total near-bottom flux. The residence time is about 1.6 years for the sedimentary metabolic organic carbon in the upper 45 cm. The dominant partitioning of the benthic utilization in the carbon budget suggests that most of labile organic carbons are consumed at or near the sediment-water interface and are left over to the sediment column by significantly diminished amounts.

• The Korean Journal of Quaternary Research
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• v.22 no.1
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• pp.23-27
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• 2008

Paleoenvironmental evolution in South Korea is investigated on the basis of fluctuations in biogenic silica content in sediments from Cheollipo coast on western shore. The biogenic silica measurement was done by alkaline extraction technique. The concentration of the biogenic silica in the Cheollipo coastal sediments is generally low, with an average of 1.2 %. The proxy of biogenic silica records in Cheollipo sediments implies the significant difference of bio-productivity on Korean Peninsula in comparison with those in lacustrine sediments in interior terrestrial continent of the Eurasia.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.268-277
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• 2019

Severe damages will result in human society, when several different critical natural phenomena coincide. One example relates to the resting cysts of Alexandrium species (dinoflagellates that cause paralytic shellfish poisoning), which are preserved in surface sediments throughout Osaka Bay, Japan. These cysts have been found to accumulate particularly densely in shallow areas in the inner parts of Osaka Bay, where a tsunami caused by an earthquake could occur any time. Damage by a tsunami could cause a change of the coastal ecosystems at Osaka Bay including the resuspension of surface sediments containing resting Alexandrium tamarense cysts and the subsequent redistribution of the cysts in newly deposited sediment. Under certain environmental conditions, these cysts could germinate and form dense blooms, leading to paralytic shellfish poisoning. Such a scenario could also affect other coastal areas, including the southern coast of the Korean Peninsula.

• 한국해양학회지
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• v.13 no.2
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• pp.11-16
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• 1978

The contents of heavy metals were studied on sediments collected from the southeastern coastal area of Korea.Concentrations of the elements showed Cu 14∼ 48ppm (av. 18ppm), Pb 14∼49ppm (av. 28ppm), Zn 79∼187ppm (av. 11ppm), Co 11∼ 15ppm (av. 13ppm), Ni 22∼32ppm (av. 29ppm), Fe 3.1∼5.3% (av. 4.3%) and Mn 333 ∼1010ppm (av. 499ppm). When these values are compared with those of the unpolluted near-shore sediments from other countries,there seems to be little environmental contamination of heavy metals in the sediments of the study area. However, from the fact that the nearer to harbor the stations are, the higher the contents of copper, lead and zinc are in the sea off Pusan Bay, it is suggested that heavy metals in the sediments are starting to show some contamination from man's activities.

• Fisheries and Aquatic Sciences
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• v.4 no.2
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• pp.58-64
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• 2001

Eight chlorobenzenes (out of a total of 12 in the congener series) were measured in the sediments from 21 stations in the southeastern coastal areas of Korea. The levels of total chlorobenzene isomers varied between 2.08 and 12.45 ng/g dry weight. The highest contents of total chlorobenzenes (CBs) were found in the sediments from Pohang coast. Trichloro­benzenes (the sum of 1,3,5-, 1,2,4- and 1,2,3-trichlorobenzene) were dominant classes among four congeners, whereas tetrachlorobenzenes (the sum of 1,2,3,5-, 1,2,4,5- and 1,2,3,4-tetra­chlorobenzene) and pentachlorobenzene were low levels. The contributions of total CBs showed similar patterns for all stations with positive significant correlation within CBs species. It means that CBs contamination in the southeastern coasts of Korea came from the similar source.