• 한국물환경학회지
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• 제28권6호
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• pp.819-832
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• 2012

HSPF model based on BASINS was applied for the Hwaseong Reservoir watershed (HRW) to evaluate the feasibility of water quality management. The watershed was divided into 45 sub-basins considering various watershed environment. Streamflow was calibrated based on the measured meteorological data, discharge data of treatment plants and observed streamflow data for 2010 year. Then the model was calibrated against the field measurements of water qualities, including BOD, T-N and T-P. In most cases, there were reasonable agreements between observed and predicted data. The validated model was used to analyze the characterization of pollutant load from study area. As a result, Non-point source pollutant loads during the rainy season was about 66~78% of total loads. In rainy-season, water quality parameters depended on precipitation and pollutant loads patterns, but their concentration were not necessarily high during the rainy season, and showed a decreasing trend with increasing water flow. As another result of evaluation for load duration curves, in order to improve water qualities to the satisfactory level, the watershed managements considering both time-variant and pollution sources must be required in the HRW. Overall, it was found that the model could be used conveniently to assess watershed characteristics and pollutant loads in watershed scale.

• 생태와환경
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• 제40권2호
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• pp.214-222
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• 2007

본 연구에서는 국내 분포하고 있는 490개 저수지를 대상으로 유역특성과 수질과의 관계를 조사하였고, TSI편차분석을 통해 유형을 구분하여 영양염 측면에서의 각 유형별 특성을 조사하였다. 본 연구 대상저수지에서 수심이 얕을수록 부영양화 가능성이 높게 나타났다. 유역 내 논과 밭의 이용면적이 30%이상인 경우 수체 내 TP농도는 평균 0.1 mg $L^{-1}$ 이상이었다. TN 농도는 유역전체면적 중 논의 면적이 25% 이상인 경우에 평균 2.6 mg $L^{-1}$이상의 분포를 나타냈다. TSI편차를 통해 구분된 형태 중 TYPE III에 해당하는 저수지의 수질항목별 평균 농도는 다른 두 형태에 포함된 저수지에서 보다 2배 이상 높은 수준이었다. TYPE III에 포함된 저수지는 다른 두 유형에 포함된 저수지와 비교해 부영양상태이고, 수심이 얕으며, 수표면적에 대한 유역면적비 (DA/RA)가 작고, 논과 밭으로의 이용면적이 넓었다. TYPE I과 II에 포함된 저수지의 수질은 TYPE II에서 BOD와 엽록소 ${\alpha}$농도가 높은 것을 제외하고는 유사한 수준이었고, 형태학적 특성(평균수심, DA/RA)이나 토지이용형태 또한 유사하였다. TYPE I에 포함된 저수지들에서는 인이 조류성장에 대한 일차적인 제한요인은 아닌 것으로 나타났다. 본 연구에서 모든 대상저수지에서 인의 제한가능성이 나타났으며, 토지이용형태, 특히 유역 내 논과 밭으로의 이용면적은 저수지의 수질을 결정하는 매우 중요한 인자였다.

• 한국농공학회지
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• 제42권5호
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• pp.84-93
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• 2000

To provide the basic information for the water improvement and control of water resource in Boryung fresh water reservoir watershed, the characteristics of stream sediments and water quality of the watershed were investigated through 16 times totally, form November in 1998 to March in 2000. The COD values of stream water quality of the Boryung fresh-water reservoir watershed ranged from 0.75 to 6.38. Total -N concentration affected by the livestock wastes and agricultural activity ranged from 0.45 to 21.80mg/L and which was almost over the quality standard of agricultural water(1.0mg/L). Total-P concentration ranged from 0~0.176 mg/L and average value 0.031 mg/L . The contents of heavy metals from 138.4 to 3,457.3mg/kg and total-P were from 210.0 to 468.3 mg/kg. These were very high according to the influence by the livestock waste and sewage water partly.

• 한국환경과학회지
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• 제22권5호
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• pp.523-531
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• 2013

In this study, a method of simulating ephemeral stream runoff characteristics in Jeju watershed is newly suggested. The process based conceptual-physical scheme is established based on the SWAT-K and applied to Cheonmi-cheon watershed which shows the typical pattern of ephemeral stream runoff characteristics. For the proper simulation of this runoff, the intermediate flow and baseflow are controlled to make downward percolation should be dominant. The result showed that surface runoff simulated by using the modified scheme showed good agreement with observed runoff data. In addition, it was found that the estimated runoff directly affected the groundwater recharge rate. This conceptual model should be continuously progressed including rainfall interception, spatially estimated evapotranspiration and so forth for the reasonable simulation of the hydrologic characteristics in Jeju island.

• 한국농공학회논문집
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• 제46권3호
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• pp.43-54
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• 2004

For a given watershed that consists of urbanized areas, it was essential to predict how the runoff characteristics, such as runoff peak and volume, and travel time, change with time far planning and designing various kinds of hydraulic facilities with given recurrence interval. In this study, Mushim stream watershed was simulated using HEC-HMS model to get runoff characteristics of an urbanization basin. The results was showed that runoff was increased $1794.20{\sim}2104.65\;m^{3}/s$> and $1751.90{\sim}1961.30\;m^{3}/s$ according to the increased of rainfall and CN value recurrence interval in years. Observed storm was increased $497.91{\sim}581.71\;m^{3}/s$ and $506.57{\sim}537.01\;m^{3}/s$ for increased of CN value and impervious area. This paper is also possible to evaluate the effect of urbanization quantitatively.

• 한국농공학회논문집
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• 제47권3호
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• pp.77-86
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• 2005

A monitoring study has been conducted to identify hydrologic conditions, water quality and nutrient loading characteristics of small watershed in Juam Lake. Climate data of the watershed were collected; flow rate was measured and water quality sampling was conducted at the watershed outlet for this study. Water quality data revealed that T-P concentrations meet I grade of lake water quality standard during non-storm period, but degraded up to II-III grade of lake water quality standard during storm period. The observed T-N concentrations always exceeded lake water quality standard. Therefore, T-P was identified as limiting chemical constituent for eutrophication of Juam Lake. T-P concentration of non-storm period also revealed that point source pollution is not serious in the watershed. Three year monitoring results showed that the observed T-N losses were $10.85\~18.88$ kg/ha and T-P losses were $0.028\~0.323$ kg/ha during six month (Mar. - Oct.), respectively. Major portion of runoff amount discharged by a few storm events a year and nutrient load showed apparent seasonal variation. Huge runoff amounts were generated by intense storms, which make application of water treatment or detention facilities ineffective. Monitoring results confirmed that water quality improvement by abating nonpoint source pollution in rural watershed of monsoon climate should be focused on source control. T-P losses from paddy field seemed to consist of significant amount of total load from study watershed. Therefore, management of drainage from paddy field is considered to be important for preventing algal blooming problem in Juam Lake.

• 산업기술연구
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• 제21권B호
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• pp.223-232
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• 2001

This study is finding the most appropriate model of kangwondo watershed. To synthesize each hydrograph, It is found to several parameters which are used in existing hydrographes. then the synthestic hydrograph is compared and investigated with many hydrographes of the rivers in kanwondo. These methods, Nakayasu, Clark, SCS are used to calculate the run-off of this watershed. When the calculated run-off is compared with real rating-curves, then it is found that the SCS method using the Clark's concentrantion time is the best way on this area having large watershed, long river length and gentle water slope, the Nakayasu method is more suitable on this area having small watershed, short river length and steep water slope. Also it is founded from analyzing run-off hydrographes, peak run-off and peak time that the Clark's method applied Kirpich's concentration time way is suitable in the area of kangwondo.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.463-466
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• 2003

The physically based distributed modelling system, MIKE SHE, has been applied to the upper sub-watershed of the Gyeongancheon watershed. A horizontal grid square was constructed to represent the spatial variations in watershed characteristics, landuse, soil, and rainfall distributions. The hydraulic model MIKE 11 was also coupled with the MIKE SHE to simulate river flow in the main and tributaries of Gyeongancheon. The simulated daily stream flow at the outlet of the watershed was compared to the observed data for the period of 1988 to 1991. The results demonstrated the applicability of a comprehensive hydrological modelling system as management tool for watershed and floodplain.

• 한국환경과학회지
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• 제17권12호
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• pp.1363-1372
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• 2008

In this study, long term semi distributed hydrologic model SWAT-K(Korea) is applied to the Seolma-Cheon watershed to analyze the hydrological components. Seolma-Cheon watershed has been operated as the test watershed of Korea Institute of Construction Technology for 13 years. Therefore it has an enough hydrologic data to analyze the hydrologic characteristics of small watershed. Especially, for the proper runoff analysis of steep watershed, calibration is performed reflecting the regression equation of slope and slope length. The simulated discharge shows good agreement with the observed one and the simulated evapotranspiration and groundwater discharge also show satisfactory results. Finally we presents the ratio of major hydrologic components for 3 years with those obsrved ones. This study is the basic research for future analyses such as relationship between hydrologic components and vegetation, watershed sediment nonpoint sources discharge etc.

• 한국농공학회논문집
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• 제57권4호
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• pp.121-133
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• 2015

The TANK model has been widely used in rainfall-runoff modeling due to its simplicity of concept and computation while achieving forecast accuracy. A major barrier to the model application is to determine parameter values for ungauged watersheds, leading to the need of a method for the parameter estimation. The objective of this study was to develop regression equations for estimating the 3th TANK model parameters considering their variations for the ungauged watersheds. Thirty watersheds of dam sites and stream stations were selected for this study. A genetic algorithm was used to optimize TANK model parameters. Watershed characteristics used in this study include land use percent, watershed area, watershed length, and watershed average slope. Generalized equations were derived by correlating to the optimized parameters and the watershed characteristics. The results showed that the TANK model, with the parameters determined by the developed regression equations, performed reasonably with 0.60 to 0.85 of Nash-Sutcliffe efficiency for daily runoff. The developed regression equations for the TANK model can be applied for the runoff simulation particularly for the ungauged watersheds, which is common for upstream of agricultural reservoirs in Korea.