• 한국해안해양공학회지
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• 제17권3호
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• pp.129-137
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• 2005

본 연구에서는 수층(water body싻 저니의 상호작용을 시뮬레이션하기위해 저질 모델을 구축하였다. 본 연구에서 구축한 모델은, 수층에서 저니층으로의 유기물질의 침강, 그리고 저니층에서 수층으로의 질소와 인의 용출을 상호작용으로 고려한 모델이다. 구축된 모델을 검증하기 위해 실측치를 이용하여 모델 재현성의 검토를 실시하였다. 오사카만을 대상으로 모델에 의해 얻어진 인의 용출속도를 실측치와 비교하였다. 그 결과 계산치와 실측치는 거의 일치하였으며, 계절별 용출속도의 변동 특성이 양호하게 재현되었다 1950년부터 1999년에 걸쳐 약 50년간 수질과 저질의 재현 계산을 실시하여 모델의 재현성과 적용성을 평가하였다. 육지로부터의 오염물질 부하량과 수질의 경계조건, 그리고 3차원 유동모델의 경계조건에 대해서는 계절별 관측치를 이용하여 설정하였다. 계산 결과 질소, 인, 그리고 COD농도 및 장기간에 걸친 수질의 변동특성이 양호하게 재현되었다.

• 한국농공학회논문집
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• 제47권4호
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• pp.65-74
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• 2005

AnnAGNPS model was applied to a catchment mainly occupied with bushland for modeling non-point source pollution. Since the single event model cannot handle events longer than 24 hours duration, the event-based calibration was carried out using the continuous mode. As event flows affect sediment and nutrient generation and transport, the calibration of the model was performed in three steps: Hydrologic, Sediment and Nutrient calibrations. The results from hydrologic calibration for the catchment indicate a good prediction of the model with average ARE(Absolute Relative Error) of $24.6\%$ fur the runoff volume and $12\%$ for the peak flow. For the sediment calibration, the average ARE was $198.8\%$ indicating acceptable model performance for the sediment prediction. The predicted TN(Total Nitrogen) and TP(Total Phosphorus) were also found to be acceptable as the average ARE for TN and TP were $175.5\%\;and\;126.5\%$, respectively. The AnnAGNPS model was therefore approved to be appropriate to model non-point source pollution in bushland catchments. In general, the model was likely to result in underestimation for the larger events and overestimation fur the smaller events for the water quality predictions. It was also observed that the large errors in the hydrologic prediction also produced high errors in sediment and nutrient prediction. This was probably due to error propagation in which the error in the hydrologic prediction influenced the generation of error in the water quality prediction. Accurate hydrologic calibration should be hence obtained for a reliable water quality prediction.

• 한국해양환경ㆍ에너지학회지
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• 제4권2호
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• pp.3-14
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• 2001

저질로부터 용출되는 영양염부하가 내만의 수질오염에 미치는 영향을 예측하기 위하여 수층과 저질간의 물질순환과정을 고려한 수-저질생태계모델(SWEM)을 개발하였다. SWEM모델은 유동을 예측하는 수리역학모델과 수층의 생태계순환 및 저질로부터의 영양염용출과정을 고려하여 수-저질간의 물질순환과정을 예측하는 생태계모델의 2개의 서브모델로 구성되어 있으며, 수치모형실험은 실시간에 의한 유동과 수질예측 계산을 실시하였다. 본 모델을 일본 博多灣에 적용하며 대상해역의 부영양화과정 및 영양염의 물질순환과정을 수치예측하고, 저질로부터 용출되는 영양염이 만내의 수질변화에 미치는 영향에 대하여 검토하였다. 모델에 의한 博多灣의 유통계산견과는 조류, 수온ㆍ염분의 관측치와 잘 일치하였으며, 물질순환예측의 계산치는 만내 수질관측치를 양호하게 재현하였다. 또한, 博多灣의 영양염 플럭스의 예측결과로부터 저질로 부터 용출하는 영양염 플럭스는 수질변화에 크게 영향을 미치고 있는 것 으로 나타났다.

• 한국양식학회지
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• 제13권4호
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• pp.303-308
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• 2000

대하 양식에 있어 저질성상에 따른 환경변화를 아질산, 암모니아 및 황화수소와 같은 유해물질을 중심으로 파악하고, 이에 따른 대하의 생존 및 성장 등에 미치는 저질조성의 영향을 검토하여 생산성을 평가하기 위하여 실험실 조건에서 6주 동안 실험하였다. 실험종료시 DO는 sand, soft sand의 단독 혹은 sand, soft sand 및 mud의 50:50 비율의 혼합조건에서는 5.1~5.9mg/l까지 감소하였으나, mud 조건에서는 4.6mg/l까지 감소하였다. 또한, 아질산, 암모니아농도 및 황화수소는 sand, soft sand의 단독 혹은 sand, soft sand 및 mud의 50:50 비율 조건에서 각각 0.07~0.12mg/l, 0.16~0.29mg/l 및 0.009~0.014mg/l까지 증가하였으나, mud 조건에서는 0.15mg/l, 0.36mg/l 및 0.018mg/l로 높은 증가를 나타냈다. 대하의 생존율은 bare와 mud 조건에서 60% 이하의 낮은 생존율을 나타냈으나, sand, soft sand의 단독 혹은 sand, soft sand 및 mud의 50:50 비율의 혼합조건에서는 70%이상을 나타냈다. 저질 성상에 따른 대하의 성장과 사료효율은 bare 조건에서 각각 7.6%와 29.4%을 나타내어 성장과 사료효율이 가장 높은 sand+mud 조건에 비해 유의한 감소를 나타냈다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제12권3호
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• pp.1-9
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• 2007

수질오염 총량제가 시행됨에 따라 깨끗한 수자원을 확보하기 위한 오염퇴적물의 관리 및 처리 필요성이 더욱 높아지고 있다. 본 논문에서는 오염퇴적물의 발생원과 오염퇴적물이 수질에 미치는 영향을 살펴보고, 오염퇴적물의 관리방향을 제시하였다. 오염퇴적물을 처리하기 위한 공법으로 준설공법과 자연정화법, 현장고정화/안정화, 생물학적 현장처리, 화학적 현장처리 공법에 대하여 요약 제시하였다. 또한 새롭게 대두되고 있는 캡핑공법을 소개하고, 오염퇴적물 처리를 위한 복합공법의 적용에 대한 개념을 제시하였다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.115-119
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• 2003

Pollutants from industry, mining, agriculture, and other sources have contaminated sediments in many surface water bodies. Sediment contamination poses a severe threat to human health and environment because many toxic contaminants that are barely detectable in the water body can accumulate in sediment at much higher levels, the purpose of this study was to make convenient sampling method and optimal treatment of sediment for water quality improvement in reservoir or stream based on an evaluation of degree of contamination. Results for analysis of S-reservoir sediments were observed that copper concentration of almost areas were higher than the regulation of soil pollution (50 mg/1) for the riverbed. S-stream sediments were observed that copper, arsenic and TPH concentration of almost areas were exceeded soil pollution concerning levels for factorial areas. We used Remscreen(version. 1.0) program which is contaminated soil recovery program to select optimal treatment method of contaminant sediments. The result was shown in the order of Thermal Calcination > Excavation, Retrieval and Off-site Disposal(comparative less then contaminant) > Low Temperature Thermal Desorption + Solidification/Stabilization.

• Water Engineering Research
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• 제7권1호
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• pp.29-41
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• 2006

The Imha watershed is vulnerable to severe erosion due to the topographical characteristics such as mountainous steep slopes. Sediment inflow from upland area has also deteriorated the water quality and caused negative effects on the aquatic ecosystem of the Imha reservoir. The Imha reservoir was affected by sediment-laden density currents during the typhoon 'Maemi' in 2003. The RUSLE model was combined with GIS techniques to analyze the mean annual erosion losses and the soil losses caused by typhoon 'Maemi'. The model is used to evaluate the spatial distribution of soil loss rates under different land uses. The mean annual soil loss rate and soil losses caused by typhoon 'Maemi' were predicted as 3,450 tons/km2/year and 2,920 ton/km2/'Maemi', respectively. The sediment delivery ratio was determined to be about 25% from the mean annual soil loss rate and the surveyed sediment deposits in the Imha reservoir in 1997. The trap efficiency of the Imha reservoir was calculated using the methods of Julien, Brown, Brune, and Churchill and ranges from 96% to 99%.

• 한국물환경학회지
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• 제27권1호
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• pp.19-29
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• 2011

In order to assess the influences of bottom sediment on water quality, following measurement were made. (1) Estimations of pollutant loads from the bottom sediment based on mass balance concept, (2) measurements of pollutant concentrations in the sediment to assess the pollution level and influence potential, (3) in situ and laboratory measurements of Sediment Oxygen Demants (SOD) and pollutant load (sediment release) from bottom sediment. Analyses of inflow and outflow loadings using simple mass balance show that there are some variations found according to the pollutants. However, there is no consistent evidence that the sediment can be a source of pollutants. Pollutant concentrations in the sediment range 16~724.8 mg/kg (COD), 1.68 ~12.64 mg/kg (T-P), 5.6~76.8 mg/kg (T-N), 0.32~21.6 mg/kg ($NH_3$-N), 0.092~0.544 mg/kg ($NO_2$-N), 4.8~18.4 mg/kg ($NO_3$-N), and 1.59~11.23 mg/kg ($PO_4$-P). Measured SOD ranges $0.190{\sim}0.802g{\cdot}m^{-2}{\cdot}d^{-1}$ and measured release rate ranges $-1618.42{\sim}10mg/m^2{\cdot}d$(COD), $-12{\sim}16mg/m^2{\cdot}d$(T-P), $-197.37{\sim}140mg/m^2{\cdot}d$(T-N), $0.4{\sim}74.32mg/m^2{\cdot}d$($NH_3$-N), $-2.04{\sim}0.8mg/m^2{\cdot}d$ ($NO_2$-N), $-70{\sim}40mg/m^2{\cdot}d$ ($NO_3$-N), and $-26.11{\sim}28.55mg/m^2{\cdot}d$($PO_4$-P). All study results indicate that bottom sediments in the Seoha weir show only limited effects on the water quality. It implies that sediment dredging is not an effective option or management measure to reduce pollutant loading.

• 한국관개배수논문집
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• 제8권2호
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• pp.64-72
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• 2001

Sihwa dyke was constructed during the period from June, 1987 to January, 1994 and the sluice gates were opened to allow sea water intrusion and outflow to improve water quality of the lake since June, 1997. Bottom sediment samples from 29 stations were co

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.984-993
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• 1993

land application of sewage sludge requires careful monitoring because of its potential for contamination of surface water and groundwater. A rainfall simulator was used to investigated the effects of freshly applied sludge on runoff of sediment and nutrients from agricultural crop lands. Rain was applied to 16 experimental field plots. A three run sequence was used to simulate different initial moisture conditions. Runoff, sediment and nutrient losses were monitored at the base of each plot during the simulated rainfall events. Sludge was surface applied and incorporated at conventionally -tilled plots and surface applied at no-till plots, at rates of 0, 75, 150 kg-N/ha. No-till practices greatly reduced runoff, sediment , and nutrient losses form the sludge treated plots, relative to the conventional tillage practices. Incorporation of the sludge was effective in reducing nutrient yields at the conventionally-tilled plots. This effect was more pronounced during the third rain torm, with wet initial conditions. Peak loadings of nutrients appeared during the rainstorm with wet initial conditions.