• Water Engineering Research
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• 제5권3호
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• pp.111-121
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• 2004

For the long-term strategic water resources planning, forecasting the future streamflow change is important to meet the demand of a growing society. The streamflow variation to the decade-long precipitation was investigated for the two major stage gauging stations in Korea. Precipitation and runoff characteristics have been analyzed at Yongwol stream stage in the Han River as well as Sutong stream stage in the Kum River for the future water resources management strategies. Monte Carlo method has been applied to estimate the future precipitation and runoff. Based on the trend line of 10-year moving average of runoff depth for the historical runoff records, the relation between runoff and the time variation was examined in more detail using regression analysis. This study showed that the surface flows have been significantly decreased while precipitation has been stable in these basins. Decreasing in runoff reflects the regional watershed characteristics such as forest cover changes. The findings of this study could contribute to the planning and development for the efficient water resources utilization.

• 한국수자원학회논문집
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• 제57권4호
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• pp.237-248
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• 2024

수문 순환의 중요한 구성 요소인 유역 유출량은 기후변동과 인간 활동의 영향으로 전 세계 많은 유역에서 크게 변화되고 있다. 기후변동과 인간 활동으로 변화되고 있는 유역 유출량에 대한 분석은 수자원 관리에 있어서 중요하다. 본 연구에서는 우리나라 5개 권역의 109개 중권역의 유출량 자료를 대상으로 기후변동과 인간 활동이 유역 유출량에 미치는 영향을 정량적으로 평가하였다. 유역 유출량 자료에 대하여 Pettitt 검정을 수행하여 분석 기간을 나누었으며, Budyko 기반 기후 탄력성 방법을 이용하여 기후변동과 인간 활동이 유역 유출량의 변화에 미치는 영향을 구분하였다. 본 연구 결과, 중권역마다 유역 유출량 변화에 기후변동과 인간 활동이 미치는 상대적인 기여도가 다양하게 나타났으며, 중권역별로 유역 유출량의 변화에 지배적인 영향을 주는 요인이 무엇인지 파악하였다. 본 연구의 결과는 기후변동과 유역 개발 계획에 따른 유역 유출량 변화를 예측할 수 있도록 하며, 이는 가뭄이나 홍수 등 수문 재해의 위험을 줄이기 위한 수자원 관리 계획을 수립하는데 중요한 정보가 될 것이다.

• 한국수자원학회논문집
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• 제37권4호
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• pp.305-314
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• 2004

온실기체의 증가에 따른 기후변화로 인해 유역에서의 물순환이 과거와는 다른 패턴을 보이고 있다. 그러나 현재의 수자원 계획 및 관리에는 기후변화의 영향이 포함되어 있지 않다. 이에 본 연구에서는 기후변화의 영향이 유역의 물순환에 어떻게 영향을 주는지를 검토하였다. 본 연구는 기존의 여러 가지 배증 $CO_2$상태의 GCM(General Circulation Model) 모의결과를 이용하여 기온 및 강수량 자료를 Markov 연쇄에 의해 모의발생 하였다. 또 강우-유출 모형을 이용하여 100년동안의 일단위 유출을 계산하였다. 그 결과 GCM 시나리오별로 연평균기온은 ＋3.2∼＋4.6$^{\circ}C$, 연평균강수량은 －7∼＋8%, 연평균유출은 －14 ∼ ＋7 % 그리고 기온 1$^{\circ}C$ 변화에 따른 잠재증발산량은 ＋3∼＋4 %의 변화를 보였다. 기후변화에 따른 영향의 평가는 GCM 모의결과에 크게 의지하지만 유황분석결과 기후변화에 따른 유출의 변동가능폭은 현재 상태보다 커질 것으로 예상된다.

• 농업과학연구
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• 제48권3호
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• pp.433-446
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• 2021

In this study, the future flood inundation changes under a climate change were simulated in the Tonle Sap basin in Cambodia, one of the countries with high vulnerability to climate change. For the flood inundation simulation using the rainfall-runoff-inundation (RRI) model, globally available geological data (digital elevation model [DEM]; hydrological data and maps based on Shuttle elevation derivatives [HydroSHED]; land cover: Global land cover facility-moderate resolution imaging spectroradiometer [GLCF-MODIS]), rainfall data (Asian precipitation-highly-resolved observational data integration towards evaluation [APHRODITE]), climate change scenario (HadGEM3-RA), and observational water level (Kratie, Koh Khel, Neak Luong st.) were constructed. The future runoff from the Kratie station, the upper boundary condition of the RRI model, was constructed to be predicted using the long short-term memory (LSTM) model. Based on the results predicted by the LSTM model, a total of 4 cases were selected (representative concentration pathway [RCP] 4.5: 2035, 2075; RCP 8.5: 2051, 2072) with the largest annual average runoff by period and scenario. The results of the analysis of the future flood inundation in the Tonle Sap basin were compared with the results of previous studies. Unlike in the past, when the change in the depth of inundation changed to a range of about 1 to 10 meters during the 1997 - 2005 period, it occurred in a range of about 5 to 9 meters during the future period. The results show that in the future RCP 4.5 and 8.5 scenarios, the variability of discharge is reduced compared to the past and that climate change could change the runoff patterns of the Tonle Sap basin.

• 방사성폐기물학회지
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• 제14권1호
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• pp.21-33
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• 2016

Estimation of groundwater hydrologic cycle pattern is one of the most critical issues in sustainable management of groundwater resources in coastal area. This study estimated groundwater percolation by using the water balance methodology and hydrogeological characteristics of land use and soil. Evapotranspiration was computed by using the Thornthwaite method, and surface runoff was determined by using the SCS-CN technique. Groundwater storage change was obtained as 229 mm/a (17.8% of the average annual rainfall, 1286 mm/a), with 693 mm/a (60.1%) of evapotranspiration and 124 mm/a (9.6%) of surface runoff. Rainfall and groundwater storage change was highly correlated, comparing with the relationships between rainfall and evapotranspiration, and between rainfall and surface runoff. This result indicates that groundwater storage change responds more sensitively to precipitation than evapotranspiration and surface runoff.

• 한국농공학회논문집
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• 제53권6호
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• pp.75-84
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• 2011

The objective of this study is to evaluate the hydrologic impacts of climate and land use changes in a rural small watershed. HadCM3 (Hadley Centre Coupled Model, ver.3) A2 scenario and LARS-WG (Long Ashton Research Station - Weather Generator) were used to generate future climatic data. Future land use data were also generated by the CA-Markov (Cellular Automata-Markov) method. The Soil and Water Assessment Tool (SWAT) model was used to evaluate hydrologic impacts. The SWAT model was calibrated and validated with stream flow measured at the Baran watershed in Korea. The SWAT model simulation results agreed well with observed values during the calibration and validation periods. In this study, hydrologic impacts were analyzed according to three scenarios: future climate change (Scenario I), future land use change (Scenario II), and both future climate and land use changes (Scenario III). For Scenario I, the comparison results between a 30-year baseline period (1997~2004) and a future 30-year period (2011~2040) indicated that the total runoff, surface runoff, lateral subsurface runoff, groundwater discharge, and evapotranspiration increased as precipitation and temperature for the future 30-year period increased. The monthly variation analysis results showed that the monthly runoff for all months except September increased compared to the baseline period. For Scenario II, both the total and surface runoff increased as the built-up area, including the impervious surface, increased, while the groundwater discharge and evapotranspiration decreased. The monthly variation analysis results indicated that the total runoff increased in the summer season, when the precipitation was concentrated. In Scenario III, the results showed a similar trend to that of Scenario II. The monthly runoff for all months except October increased compared to the baseline period.

• Membrane and Water Treatment
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• 제10권1호
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• pp.45-55
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• 2019

Climate change has significantly affected the rainfall characteristics which can influence the pollutant build-up and wash-off patterns from the catchment. Therefore, this study explored the influence of varying rainfall characteristics on urban and agricultural runoff pollutant export using statistical approaches. For this purpose, Mann-Kendall and Pettitt's test were applied to detect the trend and breakpoint in rainfall characteristics time series. In addition, double mass curve and correlation analysis were used to drive the relationship between rainfall-runoff and pollutant exports from both catchments. The results indicate a significant decreased in total rainfall and average rainfall intensity, while a significant increased trend for antecedents dry days and total storm duration over the study periods. The breakpoint was determined to be 2013 which shows remarkable trend shifts for total rainfall, average rainfall intensity and antecedents dry days except total duration. Double mass curve exhibited a straight line with significant rainfall-runoff relationship indicates a climate change effect on both sites. Overall, higher pollutant exports were observed at both sites during the baseline period as compared to change periods. In agricultural site, most of the pollutants exhibited significant (p< 0.05) association with total rainfall, average rainfall intensity and total storm duration. In contrast, pollutants from urban site significantly correlated with antecedent dry days and average rainfall intensity. Thus, total rainfall, average rainfall intensity and total duration were the significant factors for the agricultural catchment while, antecedents dry days and average rainfall intensity were key factors in build-up and wash-off from the urban catchment.

• 한국농공학회논문집
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• 제61권3호
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• pp.15-22
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• 2019

In order to preserve water environment, Total Maximum Daily Load(TMDL) is used to manage the total amount of pollutant from various sources, and the annual average load of source is calculated by the unit load method. Determination of the unit load requires reliable data accumulation and analysis based on a reasonable estimation method. In this study, we propose a revised unit load estimation method by analyzing the unit load calculation procedure of National Institute of Environment Research(NIER) method. Both methods were tested using observed runoff ratio and water quality data of rice paddy fields. The estimated values with the respective NIER and revised NIER methods were highly correlated each other. However, the Event Mean Concentration(EMC) and the runoff ratio considered in the NIER method appeared to be influenced by rainfall classes, and the difference in unit load increases as the runoff and EMC increase. The error can be further increased when the EMC and runoff ratio are changed according to changes in rainfall patterns by climate change and change of agricultural activities. Therefore, it is recommended to calculate unit load by applying the revised NIER method reflecting the non point pollution runoff characteristics for different rainfall classes.

• 대한토목학회논문집
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• 제42권3호
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• pp.333-342
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• 2022

기후변화의 영향으로 집중호우가 증가하고 있으며, 이로 인한 침수피해가 매년 발생하고 있다. 본 연구는 저영향개발(LID) 시설의 우수 유출저감 효과를 분석하기 위하여, 용두빗물펌프장 유역을 대상으로, 미국 환경보호청(EPA)의 우수유출관리모형(SWMM)을 이용하여, 과거와 미래의 대표 강우사상에 대한 유출분석을 수행하였다. 그 결과 과거 강우사상과 비교하여 미래 대표 강우사상에 대한 침투량은 3.17 % 증가하였지만, 지표면 유출량 및 첨두유량은 각각 32.50 % 및 128.77 % 증가하였다. 이러한 지표면 유출량과 첨두유량의 증가를 감소시키기 위하여 투수성 포장, 옥상녹화 및 빗물정원을 선정하였다. 세 가지 LID 시설의 매개변수와 설치 면적 비율을 조정하여 LID 시설의 적용성을 평가하였다. 그 결과 첨두유량과 지표 유출량을 감소시키고 침투량과 저류량를 증가시키는 투수성 포장, 옥상 정원 그리고 빗물 정원의 적정 매개변수를 찾을 수 있었다. 또한 투수성 포장, 옥상녹화, 빗물정원의 적용 비율이 2:1:3일 때, 첨두유량 26.85 %, 침투량 12.10 %, 지표면 유출량 15.11 %, 저류량 509.47 %의 저감효과가 나타났다. 재현기간별 우수 유출저감 효과를 분석한 결과, 재현기간이 증가할수록 첨두유량과 지표면 유출량의 비중은 늘어나고 침투량과 저류량의 비중은 줄어드는 것으로 나타났다.

• 한국수자원학회논문집
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• 제39권5호
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• pp.417-430
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• 2006

본 연구에서는 강우의 특성변화가 유출 특성에 미치는 영향을 파악하기 위하여 구형펄스모형으로 모의시킨 강우를 선형저수지 모형과 Nash 모형에 유출모의하여 그 유출량에 대한 확률밀도함수와 강우의 확률 밀도함수를 비교하였다. 이를 통해 강우의 발생빈도, 강우강도, 지속시간이 유출에 어떻게 기여하는지에 대하여 파악하였다. 소규모 유역과 중규모 유역에 대한 영향을 분석하기 위하여 두 개의 대상유역을 선정하였다. 그 결과 강우의 발생빈도, 강우강도, 지속시간의 변화에 대하여 유출량이 다양한 특성을 보이는 것을 확인 할 수 있었으며, 이는 향후 기후변화에 대한 영향을 평가하는데 적용될 수 있을 것이라 판단된다.