• Proceedings of the Malacological Society of Korea Conference
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• 2001.11a
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• pp.39-40
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• 2001

연안과 천해의 저질은 그 상층 해수의 변화에 영향을 받으며, 또한 반대로 상층의 수질을 변화시키기도 한다. 저질은 지질학적 기원을 갖는 기부위에 상층의 물에서 가라앉는 부유현탁물질과 수중생물의 배설물, 생물의 사체 등의 유기질이 층을 이루면서 형성된다. 저질은 화학적, 생물적 변화나 물의 유동에 의한 영향을 받지만 변화속도가 비교적 작고, 상층 수질의 변화 결과를 누적적으로 받기 때문에 수질변화의 평균적 이력(履歷)을 간직하며, 수역의 오염의 진행경향이나 그 속도에 대해서 수질만으로는 알 수 없는 장기간의 영향에 대한 적산적(積算的)관점에서의 정보를 보유하고 있다. 이 조사해역은 굴을 비롯한 패류 양식장이 밀집분포하고 있는 해역이며, 진해만에서 수하식 양식장의 분포비중이 가장 큰 해역으로서 양식의 역사도 30년이 넘는다. 이 해역은 외해와의 해수교류가 원활하지 못하여 양식생물의 배설물과 양식장의 탈락물이 이 육지로부터 유입되는 오염부하물질과 더불어 그대로 해저에 퇴적되고 있는 곳이라고 할 수 있다. 이 연구는 양식장 저질의 유기오염의 수준을 평가하여 양식장 및 연안해역의 관리를 위한 자료로 제공하고자 하였다.

• Journal of Navigation and Port Research
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• v.29 no.6 s.102
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• pp.589-593
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• 2005

A laboratory study on the adsorption of nitrate in polluted coastal water using various materials including several types of dredged sediments(ST) and yellow c1ays(YC), which are activated by heat(HT), bioleaching for heavy metal removal(BL) and neutralization(NR) was performed. The equilibrium time of the adsorption for the sediment bioleached and treated by heat(BL-HT-ST) was only 17min which was faster than the sediment bioleached, neutralized and treated by heat(BL-NR-HT-S) (25min) or the sediment treated by the bioleaching process(BL -ST)(27min), but longer equilibrium times for yellow c1ay(YC) or heat treated yellow day(HT- YC) were required. The adsorption processes of nitrate in sea water for tested material could be described by Freundlich isotherm, but were significantly affected by surface characteristics of the materials. The adsorption capacities for raw sediment and heat treated sediment were 2.12 and 2.19mg NO3-N/g, respectively, which were higher than others, indicating that the sediment activated by heat could be used as a material for the improvement of nearshore water quality.

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.2
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• pp.70-74
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• 2004

There is a need to have a dredging index for decision of contaminated sediments dredging. Some differences from nation to nation were found in sediment quality guideline being applied by several nations because of economic level, environmental nature, and multiple uses. Therefore, it is not reasonable to adapt one guideline to be applied to sediments dredging. In this study, we developed dredging index by combining four numerical sets of sediment quality judgement into a quadrodiagram for prudential decisions. This newly developed dredging index was applied to the data obtained from Masan Bay before and after the dredging process. The quadrodiagrams of DI give us a nice graphical comparison and numerical values to explain the relative dredging effect under the circumstances of continuous input loadings. When the guideline value of DI is determined for the judgement of dredging considering social and economic impacts on local community, the DI value will be a scientific and reasonable tool in deciding dredging area and dredging depth.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.214-215
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• 2000

1960년대 이래로 산업과 교통수단의 발달은 지역적 환경 오염을 야기시켰지만, 대량의 화석연료 및 합성화학물질의 사용은 대기와 물을 매개로 전지구적 규모의 오염형태로 진행되어 가고 있다(Simonich and Mites, 1995). 이러한 추세와 함께 환경 중 존재하는 다이옥신을 비롯한 내분비계장애물질의 오염은 극미량 존재하에도 강한 독성을 나타내므로 생태계에 끼치는 영향은 큰 것으로 보고되고 있다. (중략)

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.1
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• pp.15-20
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• 2008

Contaminated sediments are the actual cause for deterioration of coastal-ecosystem. So the developed countries have been in the process of making an effort to develop new techniques for monitoring and solving this problem since 1960. In this research, suction type pump dredging system of pilot size for collecting the filth from the seabed has been designed and manufactured that can prevent or minimize the secondary pollution by filth diffusion. For the practical use, the application possibility of the developed system has been checked through a system performance test. And, the evaluation of system performance according to the underwater body type has been carried out for system optimization by using CFD. The performance tests for checking the efficiency of sediment collecting system are done under two conditions i.e. when the system is non-operational and when the system is self-propelled. The results of this research showed the possibility of the development of dredging system to remove just the upper parts of filth from seabed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.7
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• pp.914-919
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• 2019

A mesocosm experiment considering water exchange was conducted to evaluate the change in the properties of contaminated coastal sediment. The contaminated coastal sediment sample was prepared by mixing with granulated coal ash(GCA), which is an alkaline industrial by-product. During one month of observation time, the phosphate concentration of the GCA sample case was measured to be 19.0 and 0.4 mg/L lower than that of the control sample at the pore water and overlying water, respectively. The hydrogen sulfide concentration of the GCA sample case was 5.0 mg/L, which is significantly lower than that of the control sample(112.5 mg/L). Further addition of GCA in the sediment reduced the concentrations of phosphate and hydrogen sulfide, and could enhance the adsorption reaction, when compared to the sediment without GCA. The dissolved oxygen concentration in the overlying water of the GCA sample was measured to be 3.47 mg/L higher than the control sample. From the above results, we confirmed that GCA is an effective material for reducing pollutants in coastal sediment.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.24 no.4
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• pp.287-294
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• 2012

Sedimentary environment in coastal zone has been changing due to a large number of coastal structures and continuous coastal development. As a result, the environment has been changing. In particular, the economic and environmental damage can occur due to cohesive sediment transport closely related with the fate of pollutants. Due to large sea wall construction the ebb dominance in the Mokpo coastal waters has been clearer. Cohesive sediment transport was simulated by the EFDC model. The simulated SS showed good agreements with the observed SS. From the sensitivity analysis of sediment parameters, we found out that the erosion rate, the critical shear stresses for erosion and deposition, and the settling velocity are important factors in cohesive sediment transport modeling.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.7
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• pp.469-475
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• 2014

The study investigated the physicochemical characteristics and the ecological risk of the Northport sediment in B city and the releasing properties of heavy metals into seawater during the resuspension also studied. The major components of the sediment are fine silt and clay which contains high organic matter and AVS (Acid volatile sulfide) and the ecological risk of the heavy metals in sediment also very high. The release rate of heavy metals into seawater was in order of Pb>>Cu>Cr>>Zn>Cd during the resuspension in a batch experiment, and the heavy metal release mainly attributed to the oxidation of metal sulfides. Heavy metals which came from easily oxidisable metal sulfides rapidly contaminated seawater within about 1.0 h of the sediment resuspension. The sulfide oxidation during the resuspension increased the residual fraction of heavy metals in the sediment, decreased the organic bound fraction, and changed the other fractions of heavy metals in the sediment. The release of heavy metals from the sediment during resuspension was affected by the resuspension time, the oxidation rate of metal sulfides and resuspended concentration of the sediment particle.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.1
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• pp.64-78
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• 2019

The background concentrations of heavy metals in Korean coastal sediments were estimated using heavy metal data for 495 sediments obtained from 'National Marine Ecosystem Survey (Coastal ecosystem) in 2016-2017' and the extent of contamination was assessed. Al, Cs, and Li are chosen as appropriate indicators for sediment grain size. In the relationships between heavy metal and indicators concentrations, the lowest slope data were selected through the outlier removal and residual analysis, and the background concentrations were presented as a linear regression line between metal and indicator. Comparing the previous studies for the background concentrations of heavy metals in Korean coastal sediments, concentration levels were generally consistent but those for As and Cd were presented for the first time, and the background concentration using Li as the indicator was presented for the first time.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.248-251
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• 2004

일반적으로 유기오염 물질의 경우 sequestration 또는 aging 현상에 의해 탈착저항성을 띠게 되는 것으로 알려져 있다. 그러나 중금속의 경우 흡/탈착반응은 탈착저항성이 없는 가역적 반응이라는 보고가 있는 반면 홉/탈착 반응은 비가역적이며 탈착저항성이 존재한다는 보고도 있다. 본 연구에서는 해양 연안 퇴적물에 대한 납의 흡/탈착 실험을 통하여 탈착 저항성을 화인하고 연속추출 실험을 수행함으로써 탈착 저항성 부분의 크기를 규명하고자 하였다. 그리고 각기 다른 pH(4, 6)에서 흡착 실험을 수행함으로써 pH에 따른 흡착친화도를 규명하였다. 그 결과 퇴적물에 대한 납의 흡착량은 높은 pH(6)에서 더 많았고, 각 pH 범위에서 납은 탈착저항성을 가지는 것으로 나타났으며, 연속추출결과 Organic Material bound부분에 66% 정도가 흡착되어 있음을 알 수 있었다.