• Environmental Engineering Research
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• 제20권3호
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• pp.290-297
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• 2015

This paper presents the evaluation of the impact of climate change on water resources and yield capacity of Asa and Kampe reservoirs. Trend analysis of mean temperature, runoff, rainfall and evapotranspiration was carried out using Mann Kendall and Sen's slope, while runoff was modeled as a function of temperature, rainfall and evapotranspiration using Artificial Neural Networks (ANN). Rainfall and runoff exhibited positive trends at the two dam sites and their upstream while forecasted ten-year runoff displayed increasing positive trend which indicates high reservoir inflow. The reservoir yield capacity estimated with the ANN forecasted runoff was higher by about 38% and 17% compared to that obtained with historical runoff at Asa and Kampe respectively. This is an indication that there is tendency for water resources of the reservoir to increase and thus more water will be available for water supply and irrigation to ensure food security.

• 한국환경과학회지
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• 제7권4호
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• pp.451-460
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• 1998

The objectives of this study Is to evaluate the total runoff yield, peak flow and peak flow travel time depending on the urbanization, return period and rainfall patterns at the downstream of Manchon urban watershed in TaeGu City. SWM(Storm Water Management Model) is used for runog analysis based on 5 different steps of urbanization and 4 different types of Hufrs quartile according to 8 return periods. It is analyzed that the order of total runoff yield according to raiun patterns is Huffs 4, Huffs 2. Huffs 3 and Huffs 1 quartile, that of peak flow magnitude is Huffs 2, Huffs 1, Huffs 4 and Huffs 3 quartile at present development ratio. under the 60, 70, 80 and 90ft of urbanization to the 50% of urbanization by means of the rainfall patterns, the mean Increasing ratio of total runoff yield for each case is 4.55, 11.43, 16.07 and 20.02%, that of peak flow is 5.82, 13.61, 17.15 and 18.83%, the mean decreasing ratio of peak flow travel time Is 0.00, 2.44, 5.07 and 6.26%, the mean increasing ratio of runoff depth Is 4.51, 11.42, 16.02 and 20.05% respectively. the mean increasing ratio of total runoff yield by means of each and 19.71%. Therefore, as the result of this study. it can be used for principal data as to storm sewage treatment and flood damage protection planning in urban small watershed.

• 한국농공학회논문집
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• 제60권2호
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• pp.1-11
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• 2018

Probable Maximum Flood (PMF) is mostly applied for the designs of large-scale hydraulic structures and it is estimated by computing the runoff hydrograph where Probable Maximum Precipitation (PMP) is inserted as design rainfall. The existing PMP is estimated by transferring the heavy rainfall from all watersheds of korea to the design watershed, however, in this study, PMP was analyzed by selecting only rainfall events occurred in the design watershed. And then, Catchment-scale Soil Erosion Model (CSEM) was used to estimate the PMF and sediment-runoff yield according to the watershed-based estimated PMP. Although the PMF estimated in this study was lower than the existing estimated PMF in the Yongdam-dam basin, it was estimated to be higher than the 200-year frequency design flood discharge. In addition, sediment-runoff yield was estimated with a 0.05 cm of the maximum erosion and a 0.06 cm of the maximum deposition, and a total sediment-runoff yield of 168,391 tons according to 24-hour PMP duration.

• 한국농공학회논문집
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• 제46권1호
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• pp.87-97
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• 2004

The paper presents the results from the applications of the Water Erosion Prediction Project (WEPP) model to a single plot, and also a small watershed in the Mid Korean Peninsula which is comprised of hillslopes and channels along the water courses. Field monitoring was carried out to obtain total runoff, peak runoff and sediment yield data from research sites. For the plot of 0.63 ha in size, cultivated with com, the relative error of the simulated total runoff, peak runoff rates, and sediment yields using WEPP ranged from -16.6 to 22％, from -15.6 to 6.0％, and from 23.9 to 356.4％ compared to the observed data, respectively. The relative errors for the upland watershed of 5.1 ha ranged from -0.7 to 11.1 ％ for the total runoff, from -6.6 to 35.0 ％ for the sediment yields. The simulation results seem to justify that WEPP is applicable to the Korean dry croplands if the parameters are correctly defined. The results from WEPP applications showed that the major source areas contributing sediment yield most are downstream parts of the watershed where runoff concentrated. It was suggested that cultural practice be managed in such a way that the soil surface could be fully covered by crop during rainy season to minimize sediment yield. And also, best management practices were recommended based on WEPP simulations.

• 한국수자원학회논문집
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• 제39권5호
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• pp.467-478
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• 2006

확률론적 신뢰도를 이용하여 댐의 물 공급 안전도를 정의하였다. 그리고 장기 보장 공급량의 안전도 분석에 의한 댐의 물 공급 안전도 평가 절차를 제시하였고, 소양강댐과 충주댐의 물 공급 안전도를 평가하였다. 물 공급 안전도의 평가에 펼요한 41 개의 월 유출 시계열은 SAMS-2000으로 모의 발생시켰다. 보장 공급량 결정을 위한 저수지 모의운영에는 HEC-5모형이 사용되었다. 50년 계획 기간에 대하여 설계 유출자료에 의한 소양강댐 보장 공급량의 물 공급 안전도는 80.5 %로 평가되었고, 준공 후 기록 유입량에 의한 보장 공급량의 물 공급 안전도는 53.7 %였다. 그리고 설계 유입량 자료의 보장 공급량은 14.91억 $m^3$/yr이었고, 기록 유입량 자료의 보장 공급량은 15.85억 $m^3$/yr으로 분석되었다. 기록 유입량 자료의 보장 공급량을 목표 공급량으로 하면 연간 0.94억 $m^3$의 용수를 추가 공급할 수 있다. 동일한 절차로부터, 충주댐의 설계 유출자료에 의한 보장 공급량은 33.77억 $m^3$/yr이었고, 기록 유입량에 의한 보장 공급량은 29.60억 $m^3$/yr으로 평가되었다. 충주댐의 설계 유출자료에 의한 보장 공급량을 목표 공급량으로 하였을 때, 모든 모의 발생 시계열에 대하여 물 공급 부족이 발생하였다. 충주댐의 설계 당시 봄철 유입량의 과대평가가 그 원인일 수 있다. 제안된 절차를 적용하면 보다 객관적으로 댐의 물 공급 안전도를 평가할 수 있다.

• 한국농공학회지
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• 제40권4호
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• pp.85-93
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• 1998

In the 2nd year study of a 5 year project to evaluate the soil quality and develop the best management practices for mountaineous soils, 11 runoff plots were treated and monitored with respect to physical property of the soil, runoff and sediment discharge, and the following results were obtained. 1. Bulk density and porosity did not show any siginificant difference between experimental treatments. 2. Runoff was basically dependent on the soil's physical property and tillage. Up-and-down plots showed the highest runoff while contour plots the lowest runoff. 3. Sediment yield in the mountaineous soils was directly related to tillage and residue cover. Residue covered plots showed the lowest sediment yield and up-and-down plots the highest sediment yield. And it is recommended that the best management practices using till_age and residue cover for the mountaineous soils must be developed to protect soil quality and maintain agricultural productivity.

• 한국수자원학회논문집
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• 제42권3호
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• pp.201-212
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• 2009

탱크모형과 PRMS(Precipitation Runoff Modeling-modular System) 모형으로 섬진강댐 유역의 유출량을 1981년부터 2001년까지 모의 발생하였다. 적용된 각각의 단일모형인 Tank 모형과 PRMS 모형에 의하여 모의된 유출량은 서로 상이한 모의 양상을 나타낸다. 본 연구에서는 Tank 모형과 PRMS 모형과 같은 단일모형에 의하여 모의되는 유출량의 편차를 최소화하고 관측유출량에 보다 잘 부합되는 유출모의결과를 생산하기 위하여 유전자 알고리즘 혼합유출모형을 제안하였다. 제안된 혼합유출모형은 Tank 모형과 PRMS 모형의 각각 결과를 혼합하는 모형이며, 유전자 알고리즘을 적용하여 모의 유출량과 관측 유출량을 최소화하는 Tank 모형과 PRMS 모형에 의한 각각의 유출량의 비율을 결정하는 최적배합비를 산정하였다. 제안된 혼합 모형을 섬진강댐 유역에 적용한 결과, Tank 모형 또는 PRMS 모형과 같은 단일모형으로 유출량을 모의하는 경우보다 두 개의 모형을 적절한 배합비를 도입한 혼합 모형으로 모의된 유출량은 관측유출량과의 각종오차를 작게 하는 것을 보여 주었다.

• 한국물환경학회지
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• 제29권1호
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• pp.29-35
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• 2013

Recently, various Best Management Practices (BMPs) have been applied at a field to reduce soil erosion. Hourly Runoff and Sediment Model for Best Management Practices (HRSM4BMP) model could be used to evaluate soil erosion reduction for various agricultural BMPs at fields. Runoff and sediment yield from source areas have to be predicted with greater accuracies to evaluate sediment reduction efficiently with BMPs. To achieve this, the best parameters related with runoff and sediment modules of the HRSM4BMP model should be identified with proper calibration processes. Although manual calibration is often utilized in calibrating runoff and sediment using the HRSM4BMP, objective calibration method would be recommended. The purpose of the study was to develop an automatic calibration tool of the HRSM4BMP model with PARASOL method. This automatic calibration tool was applied to Bangdongri, Chuncheon-si to evaluate its calibration performance. The $R^2$, NSE and RMSE value for runoff estimation were 0.92, 0.92, $0.3m^3$, and for sediment yield estimation were 0.94, 0.94, 0.0027 kg. As shown in this result, automatic calibration tool of HRSM4BMP model would be used to determine the best parameters and can be used to simulate runoff and sediment yield with acceptable accuracies.

• 한국농공학회논문집
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• 제56권3호
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• pp.47-53
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• 2014

We investigated the effect of straw mat cover and soil amendments on the reduction of runoff, non-point source pollution load and yield of a Chinese cabbage from alpine fields. Two plots on sandy loam soil were prepared. Experimental treatments were control and rice straw mat cover (3,300 kg/ha)+Polyacrylamide (PAM) (5 kg/ha)+Gypsum (1 ton/ha) (SPG). A variety of Chinese cabbage was cultivated and runoff was monitored during a growing season in 2012. Monitoring was conducted to seven times. Runoff rate of SPG plot was lower than those of control plot. The reduction rate of runoff from SPG plot was 29.4 % compared to control plot. The reduction rate of suspended solids (SS), total nitrogen (TN) and total phosphorus (TP) load of SPG plot was 86.5 %, 34.7 % and 39.1 %, respectively. Yield of a Chinese cabbage from SPG plot (39,646 kg/ha) was greater than that of control plots (28,482 kg/ha). It was concluded that the use of SPG on soil surface could not only reduce the NPS pollution loads in receiving waters but also help increase the crop yield.

• 한국수자원학회논문집
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• 제45권8호
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• pp.795-804
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• 2012

최근 강우강도 및 패턴이 변화함에 따라 전세계적으로 토양유실이 증가하고 있다. 그 결과, 수생태계 건전성이 악화되고, 농업작물이 피해를 입어 수확량이 감소된다. 그동안 유출 및 토양유실을 예측하거나 비점오염원을 감소시키는 연구가 많이 수행되어 왔다. USLE는 수년간 토양유실을 산정하는데 사용되어왔으나, 강우강도나 패턴변화를 적용하기에는 적절하지 못했다. 물리적 기반인 WEPP 모형은 다양한 강우강도 및 패턴변화를 적용하는데 적절하다. 본 연구에서는 WEPP 모형을 이용하여 Huff의 4분위, 다양한 강우간격, 설계강우에 따른 토양유실, 유출, 첨두유출을 산정하였다. 5분간격 강우 데이터와 60분 간격 강우 데이터를 비교한 결과 토양유실은 24%, 유출은19%, 첨두유출은 16%가 차이나는 것으로 나타났다. 유출 및 토양유실이 5분 간격 강우량에서 실측치와 가장 유사한 것으로 나타나 강우데이터의 간격이 짧을수록 더 정확하게 모의할 수 있는 것으로 나타났다. Huff의 4분위를 이용하여 토양유실량, 유출량, 첨두유출량을 산정한 결과 토양유실량, 유출량, 첨두유출량 모두 3분위에서 가장 높게 발생하는 것으로 나타났다. 강원도 홍천지역 빈도별 확률강우를 이용하여 토양유실량, 유출량, 첨두유출량의 변화를 모의하였다. 2년 빈도와 300년 빈도에서 강우량은 167% 증가하였다. 유사량과 유출량, 첨두유출량은 각각 906.2%, 249.4%, 183.9% 증가하여 유사량의 증가율이 가장 큰 것으로 나타났다. 본 연구의 결과에서 보이는 바와 같이 WEPP 모형을 이용하여 향후 기후변화에 따른 유출 및 토양유실의 예측이 가능할 것으로 판단된다.