• 한국환경복원기술학회지
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• 제3권1호
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• pp.1-9
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• 2000

The purpose of this study was to analyze the characteristics of soil erosion on the fill-slope of forest road by elapsed years after road construction. Thirteen plots were established on the fill-slope of the newly-constructed forest road, and surveyed for two years(1997~1998). In these plots, the data about soil erosion, surface runoff, vegetation coverage, slope structural characteristics and rainfall were collected. In 1997, the major causes for soil erosion were found by the correlation coefficients with the amount of surface runoff from the fill-slope, vegetation coverage, slope length, slope degree, total rainfall and max. 1 hour rainfall. But, in 1998, the major causes for soil erosion were vegetation coverage and slope degree. Using the stepwise multiple regression method, in 1997, the amount of soil erosion from the fill-slope was complexly expressed as a exponential function of statistically significant the amount of surface runoff from the fill-slope, total rainfall, slope degree of fill-slope and vegetation coverage, but, in 1998, simply expressed as a exponential function of vegetation coverage.

• 한국습지학회지
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• 제13권3호
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• pp.465-470
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• 2011

액비와 퇴비 형태로 발생되어지는 양돈 분뇨는 발생량의 대부분이 농지에 적용되어지고 있다. 과잉으로 적용된 양돈 퇴, 액비는 수계의 영양소 과잉의 주원인으로 알려지고 있는데 양돈 퇴, 액비의 질소, 인 물질이 농지로부터 지표수와 지하수로 전달되어지는 경로를 파악하는 것이 본 연구의 주목적이다. 인공 강우 시험을 통해 농지로부터 양돈 퇴비와 액비가 각각 적용되어진 농지에 대해 지하수와 지표수로 유출되는 양을 조사하였는데 질소의 경우 지하수로 유출되는 부분이 가장 많은 반면 인의 경우 토양에 흡착되는 부분이 가장 많은 것으로 나타났다. 토양에 대한 인의 평균 흡착 양은 21.5 mg P/kg soil 로 나타났다.

• Ocean and Polar Research
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• 제26권1호
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• pp.33-42
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• 2004

Effect of freshwater discharge on the long-term salt balance in the Northern and Central Indian River Lagoon (IRL) is successfully simulated by a new analytical solution to a water balance-based one-dimensional salt conservation equation. Sensitivity tests show that the salinity levels drop abruptly even during the dry season (November to May) due to the high surface runoff discharge caused by tropical storms, depressions, and passage of cold fronts. Increasing surface runoff and direct precipitation has risen by ten times, lowering the salinity level down to 12psu in the Northern Central zone, and to 17 psu in the Northern zone. However, the salinity level in the Southern Central zone has decreased to 25 psu. High sensitivity of the Northern Central zone to freshwater discharge can be partially explained by a rapid urbanization in this zone. During the dry season, less sensitivity of the Southern Central zone to the increased surface runoff is attributed to the proximity of the zone to the Sebastian Inlet and a strong diffusion condition possibly resulting from the seawater intrusion to the surficial aquifer at the Vero Beach. During the wet season, however, the whole study area is highly sensitive to freshwater discharge due to the weak diffusion conditions. High sensitivity of the IRL to the given diffusion conditions guarantees that the fresh-water release occurs during strong wind conditions, achieving both flood control in the drainage basin and a proper salinity regime in the IRL.

• 상하수도학회지
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• 제26권1호
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• pp.47-54
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• 2012

This study analyzed influence factors and the correlation among pollutants which affect occurrence of leaked pollution based on the long-term runoff flow and water quality investigation results to understand the characteristics of highway rainfall runoff pollution load. According to the result of correlation analysis on TSS (Total Suspended Solid) concentration, anteceded dry days, rainfall intensity, traffic volume and etc. as major influence factors of highway rainfall runoff pollution loads, the correlations were weak or scarce in most items. These results might be attributed that runoff pollutant concentration changes vary severely on changes of rainfall intensity and rainfall duration within rainfall and it is affected by disturbances of vehicles and street cleaning and etc. as characteristics of the highway. While Cu, Fe and Zn which are discharged with high concentrations out of heavy metals showed high correlation with particulate matter, organic matter(COD), nutrient(TN, TP), Ni and Pb showed relatively low correlation in a correlation evaluation by pollutant. Significant correlation with traffic volumes was not shown and TSS concentration even decreased in accordance with increase of the traffic volume. In the comparison with precedent studies, it was considered necessary additional analysis of the effects of rainfall section analysis, road type, disturbances of surface contaminants by vehicles, rainfall and climate conditions, surrounding terrains etc.

• 한국농공학회논문집
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• 제52권3호
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• pp.31-38
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• 2010

Various fundamental and practical theories and technologies are needed for the development of Best Management Practices (BMPs) to manage the problems. The objectives of this paper was to investigate the effect of fertilizer and Non-point suource (NPS) pollution discharges from the field. The effect of fertilizer application was measured with respect to 10 % and 20 % slopes, respectively, using artificial rainfall simulator. The effect of fertilizer application on runoff was not significant because the effect of slope and rainfall intensity were overwhelmed. Runoff from 20 % plots was 21 % larger than that from 10 % plots. While groundwater discharge from 10 % plots was about 70 % larger than that from 20 % plots. It was concluded that runoff and groundwater discharge were largely affected by slope. T-N concentration in groundwater was much higher than that in runoff for both 10 % and 20 % plots. While T-P concentration in groundwater was lower than that in runoff. It explained that T-N moved well through soil pores without adsorption and other chemical reactions but T-P was well adsorbed on the surface of soil particles.

• 한국환경농학회지
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• 제16권3호
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• pp.274-284
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• 1997

농경지로부터 농약의 유출은 수생태계 뿐만 아니라 사람에게도 영향을 미치는 중요한 요인으로, 유출될 수 있는 농약의 양에 대한 연구와 수생태계에 유입되어 환경생물에 영향을 미칠 가능성을 평가하는 환경독성학적 연구, 인체위해성에 대한 연구가 절실한 상황이다. 그러나 유출에 관여하는 요인이 너무 다양하여 단편적인 자료만으로 농약의 유출을 예측하기 어렵기 때문에 명확한 연구지침이 확립되어 있지 않으며, 국내에서도 연구가 적극적으로 시도되지 않고 있다. 따라서 농약의 유출에 대한 전반적인 연구사례 및 방법등에 대해 자연포장에서의 유출연구, 인공강우 모의포장을 이용한 유출연구, 그리고 computer 모델을 사용한 유출연구등 다양한 측면에서 고찰하여 보았다.

• 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.

• 한국농공학회논문집
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• 제54권6호
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• pp.89-99
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• 2012

An upland monitoring was conducted for about 4 years with respect to the water and quality of rainfall-runoff. The objective was to characterize of runoff and nonpoint source (NPS) pollution from a sandy field with 4.5 % in slope under balloonflower (2008-2010) and potato (2011) cultivation. Balloonflower was cultivated without any surface cover but potato was grown under plastic mulching. Runoff rate, EMCs and NPS pollution loads were estimated. The first flush effect was evaluated, and the correlation coefficient among the selected water quality indices were analyzed. Average rainfall size was higher by 2.3 mm when balloonflower was cultivated but average runoff rate was higher by 0.02 when potato was cultivated due to the plastic mulching. EMCs monitored from balloonflower field were higher than potato field except SS and TN, but all NPS pollution loads of potato field were 2.1~22.9 times greater than balloonflower field because of larger runoff volume. As a result of first flush effects, balloonflower and potato field were more influenced by increasing of accumulated rainfall and rainfall intensity rather than first flush. In the result of correlation analysis, there were no evident correlations between runoff and water quality indices. However, there were obvious correlations between SS and the other indices except TN. As a result of this study, it was thought that perennial balloonflower crop could help reduce runoff and NPS pollution loads but annual crop with plastic mulching increase them.

• 한국농공학회논문집
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• 제54권2호
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• pp.95-102
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• 2012

The objective of this research was to experimentally test the effect of rice straw mats on the reduction of runoff, sediment discharge and turbidity under a laboratory scale. We used the small runoff plots of 1 m ${\times}$ 1 m ${\times}$ 0.65 m ($L{\times}W{\times}H$) in size filled with loamy sand. Experimental treatments were bare (control), rice straw mat cover of straw mats + PAM + Gypsum (SPG), rice straw mats + Chaff + PAM + Gypsum (SCPG) and rice straw mats + Sawdust + PAM + Gypsum (SSPG); slope of 10 % or 20 %; and rainfall intensity of 30 mm/hr. Runoff volume and rate of covered plots were significantly lower than those of control plot. Average runoff rate of covered plots, slope of 10 % and 20 %, decreased 85.6 % and 72 % in respectively. Sediment reduction ratio was more than 99 % regardless of slope. The differences runoff and sediment discharge among different cover materials were not significant. It was also shown that even if runoff reduction by surface cover were low, sediment discharge reduction could be very significant and contribute to improve the water quality of streams in sloping agricultural regions. It was concluded that the use of straw mat and soil amendments (PAM and Gypsum) on sloping agricultural fields could reduce soil erosion and muddy runoff significantly and help improve the water quality and aquatic ecosystem in receiving waters. But mixing effect of PAM and Gypsum was minimal.

• 한국물환경학회지
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• 제35권1호
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• pp.72-77
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• 2019

Soil type in LID infiltration practices plays a major role in runoff reduction efficacy. In this study, the effects of infiltration rate of foundation ground under bioretention on annual runoff reduction rate was evaluated using LIDMOD3 which is a simple excel based model for evaluating LID practices. A bioretention area of about 3.2 % was required to capture surface runoff from an impervious area for a 25.4 mm rainfall event. The relative error of runoff from bioretention using LIDMOD3 is 10 % less than that of SWMM5.1 for a total rainfall event of 257.1 mm during the period of Aug. 1 ~ 18, 2017, hence, the applicability of LIDMOD3 was confirmed. Annual runoff reduction rates for the period 2008 ~ 2017 were evaluated for various infiltration rates of foundation ground under the bioretention which ranged from 0.001 to 0.600 m/day and were converted to annual runoff reduction for hydrologic soil group. The runoff reduction rates within hydrologic soil group C and D were steeply increased through increased infiltration rate but not steep within hydrologic A and B with reduction rates ranging from 53 ~ 68 %. The estimated time required to completely empty a bioretention which has a storage depth of 0.632 m is 3.5 ~ 6.9 days and we could assume that the annual average of antecedent rainfall is longer than 3.5 ~ 6.9 days. Therefore, we recommended B type as the minimum hydrologic soil group installed LID infiltration practices for high runoff reduction rate.