• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.357-366
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• 2011

BACKGROUND: Mathematical model such as GLEAMS have been developed and successfully applied to upland fields to estimate the level of pesticide residues in soil. But, the GLEAMS model rarely applied to the Korean conditions. METHODS AND RESULTS: To evaluate pesticide transport in soil residue using the GLEAMS model from pepper plot, Alachlor, Endosulfan, Cypermethrin and Fenvalerate were applied for standard and double rate. Soil sampling was conducted and decaying patterns of pesticides were investigated. Observed climate data such as temperature and irrigation amount were used for hydrology simulation. The observed pesticide residue data of 2008 were used for parameter calibration, and validation of GLEAMS model was conducted with observed data of 2009. After calibration, the $K_{oc}$ (Organic carbon distribution coefficient) and WSHFRC (Washoff fraction) parameters were identified as key parameters. The simulated concentrations of the pesticides except Fenvalerate were sensitive to $K_{oc}$ parameter. Overall, soil residue concentrations of Alachlor, Cypermethrin and Fenvalerate were fairly simulated compared to those of Endosulfan. The applicability of the GLEAMS model was also confirmed by statistical analysis. CONCLUSION(s): GLEAMS model was eligible for evaluation of pesticide soil residue for Alachlor, Cypermethrin and Fenvalerate.

• KCID journal
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• v.2 no.1
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• pp.10-19
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• 1995

Non-point source pollution due to agricultural chemicals is one of the great concerns from the viewpoint of environmental protection. Scientists have been trying to develop best management practices in agriculture in order to decrease the oater pollution

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.484-489
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• 1998

The GLEAMS nutrient submodel was evaluated to predict nutrient losses in surface runoff following application of two rates (9 and 18 t/ha) of poultry litter and a recommended rate of commercial fertilizer on corn plots. Nutrient submodel was evaluated with calibrated runoff and sediment losses to the observed field data. Simulation of nitrogen transformation effects on nitrogen losses in surface runoff did not agree with field data. The model simulated higher NH$_4$-N than NO$_3$-N losses in surface runoff, while field data showed the opposite.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.445-450
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• 2001

The objective of this study is to develop the GLEAMS-PADDY model for nutrients loading simulation from paddy-field areas. This model is developed by modifying the GLEAMS model. The model is composed of hydrology, sediment and chemical parts. The model was evaluatd using field data. The model estimates water balance and nutrients concentrations reasonably well. The model can be applied to find BMP's in the paddy areas.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.5
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• pp.106-115
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• 2002

The objective of this study was to evaluate the GLEAMS-PADDY model by applying it to estimate nutrients loading from paddy-field areas. Field data from Soro region of Chungbuk province during May to September 1999 were used for model application. Field data collected include the amounts of rainfall, irrigation water, drainage water, ET, and Percolation in hydrology Part. T-N and T-P concentrations in the rain water, irrigation water, ponded water, drainage water and percolated water were measured. The comparisons of observed and simulated water balance components and nutrient concentrations showed reasonably good agreements and the GLEAMS-PADDY model may be used to simulate nutrients loading from paddy fields. Futher research was suggested to include the erosion submodel in the GLEAMS-PADDY model to better simulate the nutrient behavior. In addition, the pesticide submodel also recommended to be included in order to simulate the various pesticide applied in paddy fields.

• Water Engineering Research
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• v.5 no.2
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• pp.55-68
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• 2004

The GLEAMS (Groundwater Loading Effects of Agricultural Management System, version 3.0) water quality model was used to predict hydrology and water quality and to evaluate the effects of soil types from a cattle-grazed pasture field of Bermuda-Rye grass rotation with poultry litter application as a fertilizer in North Alabama. The model was applied and evaluated by using four years (1999-2002) of field-measured data to compare the simulated results for the 2.71- ha Summerford watershed. $R^2$ values between observed and simulated runoff, sediment yields, TN, and TP were 0.91, 0.86, 0.95, and 0.69, respectively. EI (Efficiency Index) of these parameters were 0.86, 0.67, 0.70, and 0.48, respectively. The statistical parameters indicated that GLEAMS provided a reasonable estimation of the runoff, sediment yield, and nutrient losses at the studied watershed. The soil infiltration rates were compared with the rainfall events. Only high intensity rainfall events generated runoff from the watershed. The measured and predicted infiltration rates were higher during dry soil conditions than wet soil conditions. The ratio of runoff to precipitation was ranging from 2.2% to 8.8% with average of 4.3%. This shows that the project site had high infiltration and evapotranspiration which generated the low runoff. The ratio of runoff to precipitation according to soil types by the GLEAMS model appeared that Sa (Sequatchie fine sandy loam) soil type was higher and Wc (Waynesboro fine sandy loam, severely eroded rolling phase) soil type relatively lower than the weighted average of the soil types in the watershed. The model under-predicted runoff, sediment yields, TN, and TP in Wb (Waynesboro fine sandy loam, eroded undulating phase) and Wc soil types. General tendency of the predicted data was similar for all soil types. The model predicted the highest runoff in Sa soil type by 105% of the weighted average and the lowest runoff in Wc soil type by 87% of the weighted average

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.4
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• pp.51-61
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• 2002

The objective of this study is to develop GLEANS-PADDY model to predict nutrients loading from paddy-field areas. This model is developed by modifying the GLEANS model which is used for uplands, and composed of hydrology and nutrient submodels. The optimal field size for CLEANS-PADDY model application is about up to 50 ha with mild slope, relatively homogeneous Soils and spatially rainfall, and a single crop farming. The CLEAMS model is modified to handle ponded soil surface condition and saturated soil profile in paddy field. In the hydrology submodel of the CLEAMS-PADDY model. the ponded depth routing method is used to handle the ponded water condition of paddy field. To compute potential evapotranspiration the FAO-24 Corrected Blaney-Criddle method is used for paddy field instead of Penman-Monteith method in the CLEAMS model. In the nutrients submodel of the CLEAMS-PADDY model, the soil was assumed saturated and soil profile in the root zone was divided into oxidized and reduced zones.

• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.E
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• pp.12-19
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• 1992

The effects of drainage system on evapotranspiration and drainage flows are studied. Data from drainage field experiment at Castalia in North Central Branch, Ohio Agricultural Research and Development Center were used in this study. A water table management model, ADATP (Agricultural Drainage and Pesticide Transport), which was developed by combining the GLEAMS and the subsurface drainage part of the DRAINMOD model with several modifications, was evaluated and used to predict hydrologic components. The ET is very much affected by the presence of tile drainage system but not significantly affected by the surface drainage system. The combined surface and subsurface drainage system gives the largest total outflow values while the surface drainage only system gives the smallest. Comparisons of model predicted and measured values of surface runoff only, subsurface drainage only, and combined surface runoff and subsurface drainage system are in satisfactory agreement. The model predicted values are within the range of the variations of the observed replications in general. Based on the results of the model evaluation study, it is concluded that ADAPT model can be used to design water table management systems.

• Journal of Korean Society of Rural Planning
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• v.9 no.1 s.18
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• pp.85-93
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• 2003

Many features of the Single Field version have been enhanced to provide user friendly interface. The County/Watershed version of NAPRA WWW system was further enhanced. The newly developed Web GIS version is an ideal tool for novice users, such as farmers, to simulate the effects of agricultural management for their farms because of its easy-to-use Web GIS interface. The NAPRA WWW system provides an easy to use WWW interface and uses spatial and relational databases to simplify the process of preparing model files. Thus, the NAPRA WWW systems now can be effectively used for nutrient management as well as pesticide management to identify the least impact agricultural management practices.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.186-186
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• 2012

새만금에서 농업용수의 안정적인 확보를 위해서는 새만금호의 수질관리가 절대적으로 필요하며 농업비점오염 부하량이 총인기준으로 52~72%를 차지하는 것을 고려할 때 농업비점오염 관리는 중요하다. 이에 "새만금유역농업비점오염 저감기법 개발 연구"를 통해 논과 밭 등의 농업비점 오염원별 최적관리기법 개발을 목적으로 모니터링 연구가 수행되었다. 유역규모 물수지 및 물질수지 분석에 있어서 논은 전체 농업용수의 60%를 차지하고 있다. 특히 농업비점오염 중에서 논은 물고 및 담수심의 관리에 따라서 기타 토지이용과 상이한 유출특성을 보인다. 따라서 유역규모에서 논으로부터 발생되는 비점오염의 시공간적인 부하량의 변화를 예측하기 위해서는 반드시 논에서의 물관리와 시비관리에 따른 수량과 수질의 유출특성에 대한 분석이 선행되어야 한다. 물관리 및 시비관리 방법에 따라 논으로부터 발생되는 오염부하량이 수질에 미치는 영향을 분석하기 위해서는 논에서의 물수지 및 물질수지 모니터링 기법이 활용될 수 있다. 하지만 모니터링 접근 방식은 오랜 시간과 많은 비용을 필요로 하는 단점을 가지고 있다. 따라서 고려되어 지고 있는 여러 저감기법들 중에서 농업비점오염물질의 유출에 미치는 영향을 파악하여 가장 적합한 저감기법 (Best Managment Practices, BMPs)을 선정하기 위해서 다양한 수학적인 모형들이 사용되어 왔다. 비점오염 관리는 오염물질이 오염원에서 발생되는 양 자체를 줄이거나 또는 오염원으로부터 수체에 이르기까지의 과정에서 운송을 차단시키는 방법들을 활용하고 있다. 따라서 논에서의 비점오염 모델링 또한 논에서의 유출 특성 및 질소와 인과 같은 영양물질과 관련된 기작을 고려한 모형들이 선택 및 적용되어야 한다. 논에서의 물관리 및 시비관리를 고려할 수 있는 모형들로는 CREAMS-PADDY, GLEAMS-PADDY, PADDYMOD, APEX와 같은 모형들이 개발되어 사용되어 왔다. 따라서 본 연구에서 논으로부터의 비점오염 부하량 예측을 위해 사용되어 온 모형들의 장단점을 비교 분석하고 적합한 모형들을 동일한 시험포장에 적용하여 논 비점오염관련 모형들의 국내 적용성을 제시하였다.