• 한국관개배수논문집
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• 제10권2호
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• pp.62-70
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• 2003

강원도의 고랭지 감자밭에 3개의 침사구를 2002년도에 설치하고 유출수와 함께 배출되는 유사의 제거효과를 평가하였다. 연구유역의 토성은 사질토로 침투능이 매우 커서 강우량과 강우강도가 컸을 때만 5회의 유출현상이 발생하였다. 침사구의 유사제거 효과는 3개의 침사구에서 모두 98$\%$이상으로 측정되었다. 유사제거 효과가 매우 큰 원인중의 하나는 토성이 사질토로 유출수의 유속이 침사구에서 감소하면서 다량의 유사가 침전하였기 때문으로 분

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.607-610
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• 2003

The object of this study is to analyze the characteristics of pollutant loadings on rainy day compared with normal day in the Mangyeong catchment area of Saemangeum tidal reclaimed area. On rainy day, the concentrations of BOD, COD, T-N and T-P are smaller than those on normal day, in spite of the pollutant loading themselves are increased significantly on rainy day due to non point source pollution, such as CSOs(combined sewage overflows), runoff from agricultural land use and so on.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.63-66
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• 2003

This study applied a hydrogeological field survey and isotope investigation to identify source locations and delineate pathways of groundwater contamination by nitrogen compounds. The infiltration and recharge processes were analyzed with groundwater-level fluctuation data and oxygen-hydrogen stable isotope data. The groundwater flow pattern was investigated through groundwater flow modeling and spatial and temporal variation of oxygen isotope data. Based on the flow analysis and nitrogen isotope data, source types of nitrate contamination in groundwater are identified. Groundwater recharge largely occurs in spring and summer due to precipitation or irrigation water in rice fields. Based on oxygen isotope data and cross-correlation between precipitation and groundwater level changes, groundwater recharge was found to be mainly caused by irrigation in spring and by precipitation at other times. The groundwater flow velocity calculated by a time series of spatial correlations, 231 m/yr, is in good accordance with the linear velocity estimated from hydrogeologic data. Nitrate contamination sources are natural and fertilized soils as non-point sources, and septic and animal wastes as point sources. Seasonal loading and spatial distribution of nitrate sources are estimated by using oxygen and nitrogen isotopic data.

• 한국농공학회논문집
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• 제54권6호
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• pp.53-63
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• 2012

The objectives of this study were to develop a linked watershed-waterbody modeling system and to assess the impacts of indirect wastewater reuse on irrigation water quality. The Osan stream watershed within Gyeonggi-do of South Korea was selected for this study. The linked modeling system was composed of the SWAT (Soil and water assessment tool) and QUALKO2 models. The SWAT model was calibrated and validated using the stream discharge and water quality data from 2010 to 2011. Runoff and non-point source pollutants from each subbasin and stream discharge from 1980 to 2009 were simulated by the SWAT model and applied to the QUALKO2 model. The QUALKO2 model was calibrated and validated under the conditions of low water and normal discharges, respectively. Finally, The 10-day irrigation water quality from April to September was simulated. The statistical measures of coefficient of determination ($R^2$), reliability index (RI), and efficiency index (EI) were used to evaluate the system performance. The $R^2$, RI and EI values ranged from 0.5 to 1.0, 1.03 to 1.92, and -35.03 to 0.95, respectively. The 10-day irrigation water quality showed the concentrations of BOD and coliform exceeded the water quality guidelines for wastewater reuse. The linked modeling system can be a useful tool to estimate non-point source pollutant loads in watershed and to control the water quality of effluent from a wastewater treatment plant and irrigation water in the downstream waterbody.

• 한국농공학회논문집
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• 제55권4호
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• pp.21-28
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• 2013

The objective of the study was to investigate the effect of rice straw mat, rice straw mat with PAM (Polyacrylamide) and gypsum addition on surface runoff and sediment discharge in field. Six experimental plots of $5{\times}22m$ in size and 3 % in slope prepared on gravelly sandy loam soil were treated with control, rice straw mat cover with gypsum and rice straw mat cover with gypsum and PAM. Radish in Spring and Chinese cabbage in autumn growing seasons were cultivated. Non point source (NPS) pollution discharge was monitored and compared among the treatments. Rainfall of the 10 monitored events ranged from 17.0 mm to 93.5 mm. Runoff coefficient of the events was 0.005~0.239 in control plot, 0~0.176 in rice straw plot with gypsum and 0~0.046 in rice straw mat plot with gypsum and PAM. When compared to the control plot, the runoff amount was reduced by 10.4~100 % (Ave. 60.8) in rice straw plot with gypsum and 80.7~100 % (Ave. 96.7 %) in rice straw mat plot with gypsum and PAM. The reduction of NPS pollution load was 54.6 % for BOD5, 71.5 % for SS, 41.6 % for TN and 61.4 % for T-P in rice straw with gypsum plot and 91.9 % for BOD5, 92.0 % for SS, 88.0 % for TN and 88.5 % for T-P in rice straw mat with gypsum and PAM plot. This research revealed that rice straw mat cover with soil amendments on the soil surface could not only increase the crop yield but also reduce the NPS pollution loads substantially.

• 한국환경농학회지
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• 제20권3호
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• pp.192-200
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• 2001

우리 나라의 농업지대 소유역에서 질소와 인의 부하에 대한 농업비점오염 모형 AGNPS의 적용 가능성을 검토하고자 경북 영천군 임고천 유역에서 조사된 실제 강우사상에 대하여 강우사상별로 실측치와 모형의 예측치를 비교하였다. CN 식에 대한 보정을 거친 모형을 적용한 결과, 첨두유량은 강우에 따라 다소 차이는 있었으나 예측치는 모형효율 0.97로 실측치와 거의 일치하였다. 이는 유역의 특성을 고려하여 CN 식을 수정하였고 유역의 동질성을 위해 격자망을 비교적 세분화하였기 때문으로 판단된다. 총 질소와 총인 농도의 경우의 실측치와 예측치를 비교하면 모형효율은 각각 0.93과 0.74였으며, 총인의 경우 총질소에 비해 결정계수가 비교적 낮은 것은 토지 이용에 따른 시비 및 생활 및 축산 오수 유입 등의 차이에 상대적으로 민감하게 영향을 받았기 때문으로 판단된다. 농업비점오염 부하를 예측하는 모형인 AGNPS는 적용 대상 유역의 특성을 잘 고려하여 매개변수들을 적절히 보정하고 정확한 입력자료를 확보하면 우리 나라 소규모 농업 유역에서도 활용될 수 있을 것으로 판단된다.

• 한국농공학회논문집
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• 제58권4호
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• pp.67-74
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• 2016

Load Duration Curve (LDC) can be used as a method for load management of point and non-point pollution source because the LDC easily assesses the water quality corresponding to hydrological changes in a watershed. Recently, the application of LDC to total pollution load management is a growing interest in Korea. In this regard, A desktop-based LDC assessment system was developed in this study to provide convenience to users in water quality evaluation. The developed system can simply produce the LDC by using streamflow and water quality data involved in its database. Also, The system can quantitatively inform the success or failure of the achievement for a target water quality at monthly scale. Furthermore, seasonal water quality and point/non-point pollution load in a watershed can be estimated by this system. We expect that the developed system will contribute to establish local and national policies regarding water management and total pollution load management because of its advantages such as the pollution tracking investigation and the analysis of water quality and pollution loading amount in an ungauged watershed.

• 한국환경농학회지
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• 제22권4호
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• pp.266-272
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• 2003

호주 시드니 인근 도 농 복합 소도시로부터 발생하는 비점오염원을 처리하기 위하여 설치된 Plumpton park와 Woodcroft park 인공습지의 처리효율을 살펴본 결과, 수생식물의 밀도가 증가하고 식생이 안정된 Plumpton Park 인공습지에서 T-P의 26.2%, T-N의 38.3%, 식생분포가 안정적이지 않은 Woodcroft park에서 14.0%와 20.2%가 각각 제거됨으로서 인공습지에서 식물체와 식물체 근권 미생물에 의한 T-P 및 T-N의 제거 효율이 상당히 큼을 알 수 있었다. 또한 T-N와 T-P에 비하여 $NH_4-N$, $NO_3-N$, $PO_4^{-3}$의 제거율이 높았던 것은 무기태 형태의 영양염류가 식물 및 미생물에 더 쉽게 이용되었기 때문으로 생각된다. 이상의 결과로 볼 때 인공습지에서 식물체와 근권 주위 미생물에 의한 염류제거는 인공습지가 설치한지 오래되었을 때도 효과적이었고, 또한 인공습지는 무기태 영양염류의 제거효율이 더욱 높았으므로 무기화학비료 등의 용탈이 일어나기 쉬운 농경지 비점오염원으로 부터 발생하는 수질오염의 개선에 이용할 수 있는 경제적이고도 효율적인 system으로 고려되었다.

• 한국농공학회지
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• 제42권5호
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• pp.103-113
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• 2000

A decision support system DSS-WQMRA (Decision Support System-Water Quality Management in Rural Area) was developed to help regional planners for the water quality management in a rural basin. The integrated model DSS-WQMRA, written in JAVA, includes four subsystems such as a GIS, a database, water quality simulation models and a decision model. In the system, the GIS deals with landuse and the location of pollutant sources. The database manages each data and supplies input data for various water quality simulation models. the water quality simulation model is composed of the GWLF( Generalized Watershed Loading Function), PCLM(Pollutant Loading Calculation Module) and the WASP5 model. The decision model based on mixed integer programming is designed to determine optimal costs and thus allow the selection of managemental practices to meet the water quality criteria. The methodology was tested with an example application in the Bokha River Basin, Kyunggi Province in Korea. It was proved that the integrated model DSS-WQMRA could be very useful for water quality management including the non-point source pollution in rural areas.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.519-524
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• 2000

The goal of this research is the establishment of a connection of an existing water quality model to GIS. The water quality model investigated was the Water Quality Analysis Simulation Program (WASP5), while the actual linkage was performed using object-oriented programming. The runoff and the non-point source loadings into the Channel were determined using a grid-based model developed in GIS. Afterwards, scripts were written in the ArcView programming language, Avenue, in order for ArcView to perform the following tasks : 1) write the input file informations, 2) format the input information into the proper WASP5 file, 3) execute the WASP5 subprogram for modeling.