• 환경영향평가
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• 제3권2호
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• pp.47-56
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• 1994

AGNPS model is an event-based model to analyze nonpoint-source and to examine potential water quality problems from agricultural watershed. This model uses a square grid-cell system to represent the spatial variability of watershed conditions, and simulates runoff, sediment, and nutrient transport for each cell. AGNPS model was applied on Yeonwha watershed, and the test results were compared with the measured data for runoff volume, peak runoff rate, suspended solids, and phosphorus concentration. The watershed of 278.8 ha was divided into 278 cells, each of which was 1 ha in size. The coefficients of determination for runoff volume and peak flow were (0.893 and 0.801 respectively from regression of the estimated values on the measured values. The concentration of suspendid solid was increased but decreased that of phosphate with runoff volume.

• 농약과학회지
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• 제18권4호
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• pp.236-246
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• 2014

농약은 작물을 보호하기 위하여 사용되지만 환경을 오염시키는 원인이 되기도 한다. 그러므로 농약의 물리화학적 특성, 독성 자료 및 환경행적 자료를 통해 위해성 평가를 수행하여 안전하게 관리가 가능하다면 등록이 결정된다. 환경중 행적을 예측하기 위해 우리나라의 기상자료, 작물 재배력 및 토양통을 이용하여 butachlor, iprobenfos, carbofuran, tebuconazole을 대상으로 수계 중 잔류농도를 추정하였다. 예측모형으로 과수용 농약은 PA5를, 벼재배용 농약은 RICEWQ와 SCI-GROW를 이용하였다. 수계모니터링에서 butachlor와 iprobenfos의 최대값은 예측모형의 peak 농도보다 낮았고 최소값은 예측모형의 연평균농도보다 낮아 RICEWQ를 벼 재배환경 중 잔류농약의 농도 추정에 이용할 수 있음을 확인하였다. 토양흡착계수가 낮은 carbofuran은 RICEWQ와 SCI-GROW에 적용시 지표수계보다 지하수로의 이동량이 훨씬 많은 것으로 산출되어 RICEWQ는 지하수로의 수계노출농도를 예측하기에는 적절하지 못하였다. 수계 모니터링에서 과수용 농약인 tebuconazole이 검출되지 않아 예측모형으로 산출한 값과 비교하기 어려웠으나 수계를 통한 잔류농약의 추정에 이용할 수 있을 것으로 사료된다.

• 한국환경과학회지
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• 제20권3호
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• pp.417-426
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• 2011

This study was conducted to investigate runoff characteristics of non-point pollutants source at the urban and rural zones in sangju area. The monitoring was conducted with seven events for ten months and Event mean Concentration(EMC) and First Flush Effect(FFE) of SS and BOD were calculated on the result of the water quality parameters. During rainfall event, the peak concentrations of SS and BOD were observed after 3~4 hours of rainfall in rural areas. Whereas, the peak concentrations occurred within 1~2 hours after rainfall and then the highest concentration of NPS pollutants sharply decreased, showing strong first flush effect in urban areas. The cumulative load curves for NPS pollutants showed above the $45^{\circ}$ straight line, indicating that fist flush effect occurred in urban areas. The mean SS EMC values of rural areas ranged from 0.9~3.3mg/L, it was higher value when compare to urban areas. While the mean BOD values of urban areas were shown the highest values.

• 한국산림과학회지
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• 제89권3호
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• pp.342-355
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• 2000

본 연구는 물순환모델을 이용하여 계류수의 유출성분을 직접유출과 기저유출로 분리한 각각의 유출성분과 계류수질의 장 단기 수질 관측을 통해 얻어진 pH, EC 및 용존이온들과의 관계를 파악하여 유출량의 변화가 물질수지 및 계류수질에 미치는 영향을 밝히기 위하여 실시하였다. 팔공산 수문관측유역에서 1998년 1월부터 1999년 9월까지 관측한 수문 및 수질자료를 대상으로 유출량과 수질변화 특성과의 관계를 분석한 결과는 다음과 같다. 1. 계류수의 연평균 pH는 1998년에 6.48(6.22~6.89)로, 1999년에 6.52(5.75~7.18)로 나타나 대체로 일정한 값을 유지하고 있었으며, 시험유역에서 간벌이 실시된 이후 4개월 동안은 계속해서 pH가 낮아져 간벌이 영향을 미친 것으로 나타났다. 2. 계류수의 연평균 EC는 1998년에 $26.69(17.95{\sim}33.5){\mu}S/cm$로, 1999년에 $25.19(17.5{\sim}33.8){\mu}S/cm$로 나타나 시험유역에서 연중 일정한 값을 나타내었다. 3. 강우와 계류수의 평균 용존 물질량을 비교한 결과, 분석된 이온들 중 $K^+$를 제외한 나머지 이온 $Na^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, $NO_3{^-}$, $SO_4{^{2-}}$는 모두 마이너스 수지를 나타냈다. 그리고, 계류수의 용존원소 가운데 양이온은 $Na^+$가 가장 농도가 높았으며, 음이온은 $NO_3{^-}$가 가장 많이 검출되었다. 4. 단위강우로부터 발생한 계류수 pH의 경시변화를 분석한 결과, 유량이 증가하면 pH가 낮아지다가 첨두유량을 전환점으로 해서 유출량이 감소하면 다시 pH가 높아지는 것으로 나타났다. 5. 계류수 EC의 경시변화를 분석한 결과, 강우초기의 유량증가시에는 EC값이 감소하지만 첨두유량을 전후로 해서 유량의 증감에 따라 EC값이 함께 변화하는 것으로 나타났다. 6. 계류수의 $Na^+$, $K^+$, $Ca^{2+}$, 양이온총량, $Cl^-$ 및 $SO_4{^{2-}}$는 유출량이 증가하면 농도가 낮아지지만, 유출량이 감소하면 농도가 높아지는 경향을 나타내었으며, $NO_3{^-}$와 음이온총량은 그 반대의 경향을 나타내었다. 그리고, $Mg^{2+}$는 뚜렷한 경향이 나타나지 않았다. 7. 물순환모델에 의해 분리된 직접유출, 기저유출 및 총유출 성분 중 pH, EC 그리고 양이온 및 음이온 농도에 가장 큰 영향을 미치는 유출성분은 기저유출로 나타났다.

• 한국물환경학회지
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• 제23권1호
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• pp.52-63
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• 2007

The objectives of this study were to setup a laterally-averaged two-dimensional eutrophication model in Daecheong Reservoir, and to validate the model under two different hydrological conditions; drought year (2001) and wet year (2004). The suggested modeling approach was found to be very effective to simulate the dynamic variations of water temperature, nutrients, dissolved oxygen, and algae in the reservoir. The model satisfactorily replicated the algal bloom that happened between Janggae (Sta.4) and Haenam (Sta.5) during summer of 2001, although the peak concentration was slightly underestimated due to the laterally averaged assumption. The allochthonous phosphorus and algae induced from upstream and So-oak stream during several rainfall events were found to be most significant sources of algal bloom in 2001. In contrast to draught year, the flood events happened during summer months of 2004 tended to remove the hypolimnetic anaerobic conditions and dilute the dissolved phosphorus in the upper reach of the reservoir, and in turn mitigated algal bloom. It implies that the impact of hydrological and hydrodynamic conditions on the reservoir water quality is highly significant, and a drought year may be more vulnerable to algal bloom in the reservoir.

• 한국수산과학회지
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• 제25권3호
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• pp.197-204
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• 1992

넙치양식장의 수질관리 및 제어 방안을 검토하기 위하여 같은 조건에서 양식되고 있는 유수식 및 순환여과식 양식장을 선택하여 상호수질의 비교 평가를 행하였다. 두양식장 공히 COD, $PO_4-P$ 및 SS의 최대농도는 급이와 동시에 나타났고 2시간 이내에 평상농도로 회복되어 일정한 농도로 거의 유지되었다. $NH_4-N$의 경우 유수식에는 급이후 시간 경과에 따라 농도차이가 별로 없으나 순환식의 경우는 급이후 2시간 이후에 다소 증가하는 경향을 보였다. $NH_4-N$을 제외한 COD, $PO_4-P,\;SS$ 및 TIN의 농도는 순환여과식에서 다소 높은 경향을 보였다. 이는 처리 시스템내에 축적된 유기부유물이 무기화에 기인된 것을 평가되었으며, 이것이 질산화율을 떨어뜨리는 결과를 초래한 것으로 사려되었다. 유수식 및 순환여과식의 수질에 직접적인 영향을 주는 해수 교환율이 양식장마다 크게 다르게 나타나 이에 대한 최적화가 시급한 것으로 나타났다.

• Water Engineering Research
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• 제1권3호
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• pp.171-185
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• 2000

A mathematical model to adequately predict complex mixing characteristics of sorptive polluants in natural streams with pools-and-riffes has been developed. In this model, sorption of pollutants onto the bed sediment as well as mass storage and exchange in the storage zones were incorporated into one-dimensional mass balance equatins. The geometric and hydraulic characteristics of the pool-riffle sequences were properly conceptualized. Simulations with parameters of pool-and-riffle streams better fit the measured data in overall shape and peak concentration than simulations with parameters for uniform channels. The analyses on the characteristics of the storage zone model parameters reveal that a linear relationship between the logrithm of the storage zone volume ratio and a function of the friction factor exists. A linear relatiohship might also be tenatively assumed between the logarithm of the dimensionless mass exchange coefficient and the logarithm of the aspect ratio of the storage zone if some of the high values of the dimensionless mass exchange coefficient collected on the successive bed forms are excluded.

• 한국물환경학회지
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• 제24권1호
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• pp.69-77
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• 2008

This study was conducted to know the characteristics of agricultural non-point source pollutants runoff by rainfall events at the upper catchment of Goseong reservoir in Gonjy city, Chungnam Province. For this study, the monitoring sites of the research catchment were set nineteen during the research period (between June 2005 and October 2006). Average runoff coefficient were observed 0.51 in 2005, 0.71 in 2006, respectively. The correlation coefficient (r) between the rainfall and peak-flow was investigated 0.787. By rainfall events, the water quality of the sites were shown like this : BOD 0.555~9.60 mg/L, T-N 0.01~13.50 mg/L, T-P 0.002~2.952 mg/L, and SS N.D~820.0 mg/L. The strong rainfall intensity was the most important factor of the soil erosion. The gabs of the arithmetic mean concentrations and the flow weighted mean concentrations were observed as the followings : BOD 0.0~29.2%, T-N 0.1~11.4%, T-P 0.4~95.2%, and SS 1.7~57.0% in 2005, and BOD 1.0~11.9%, T-N 0.7~7.3%, T-P 9.9~36.5%, and SS 6.6~36.5% in 2006, respectively. The BOD pollution load was 2,117 kg (36% of the total BOD loading of survey periods) while, T-N was 3,209.0 kg (27.9% of the total T-N loading of survey periods), T-P was 136.4 kg (37.4% of the total T-P loading of survey periods) and SS was 72,733.8 kg (51.8% of the total SS loading of survey periods) in the year 2005. In case of 2006, BOD load was 1,321.7, T-N was 2,845.8, T-P was 42.9, and SS was 16,275.8 kg, respectively.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.472-472
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• 2023

본 연구에서는 낙동강 수계에서 발생한 수질오염사고에 대해 K-River와 K-DRUM 결합모형을 이용하여 오염물질의 이동을 분석하였다. 국내에서는 수질오염총량제 도입 이후 수질관리에서 물순환과정을 수용한 배분모델의 필요성과 비점오염원의 중요성이 강조되었다. 따라서 비점오염원의 유출특성을 반영하기 위해 유역의 오염도를 분석할 수 있는 K-DRUM 분포모형을 사용하였다. 그리고 낙동강 수계에서 운영되는 댐 운영규칙을 적용하여 모델의 재현성을 높였다. 또한 하천 내 오염물질의 이동을 분석하기 위해 대류-분산 방정식의 대류 부분만을 1차원 수리모델 K-River에 적용하여 오염물질 추적을 수행하였다. 수질오염 분석 결과 오염물질의 최고농도는 과소평가 되었으나 도착시간과 전체 오염물질 농도의 추이는 잘 재현되었다.

• 한국환경과학회지
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• 제22권3호
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• pp.259-267
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• 2013

In this study, non-point source(NPS) contribution was investigated based on flow rates and water qualities of streams into the lake during rainfall events. Event mean concentration(EMC) and the pollution loads were calculated to establish a database for NPS control measurement in the survey area, and so on. The runoff characteristics of NPS were investigated and estimated on the basis of the ratio of an agricultural to forest area in the stream of sub-catch basin during rainfall events. Non-point source pollution loads were also calculated to establish a database for NPS control measure in the upstream lake Chinyang. At a rainfall event, BOD concentrations rise sharply at the early peak time of runoff, however, peaks of TSS concentration were observed at the similar time of peak flow. This was a phenomenon shown at the watersheds caused by forest and geological types. The discharged EMC range was 2.9-4.8 mg/L in terms of BOD. The discharged EMC range was 6.2-8.2 mg/L in terms of SS. The discharged EMCs of T-N and T-P were 1.4-2.5 mg/L and 0.059-0.233 mg/L, respectively. Total BOD loading rate through the 3 tributaries to the lake Chinyang was 1,136 kg/d during dry weather. The upper watershed area of the Nam-river dam in this study was divided into 14 catchment basins based on the Korean guideline for total maximum daily load(TMDL) of water quality pollutants. The higher the agricultural land-use ratio, the more NPS loading rate discharged, but the more occupied a forest area, the lower more NPS loading rate discharged. In an agricultural land-use area more than 20%, the increase of NPS loadings might be dramatically diffused by increasing the integrated complex-use like vinyl-house facilities and fertilizer use etc. according to the effective land-use utilization. The NPS loading rates were BOD 0.3 $kg/ha{\cdot}day$, SS 0.21 $kg/ha{\cdot}day$, TN 0.02 $kg/ha{\cdot}day$, TP 0.005 $kg/ha{\cdot}day$ under less than 10% agricultural land-use. In agricultural land-use of 20%-50%, these values were investigated in the range of 0.32 $kg/ha{\cdot}day$-0.73 $kg/ha{\cdot}day$ for BOD, 0.92 $kg/ha{\cdot}day$-3.32 $kg/ha{\cdot}day$ for SS, 0.70 $kg/ha{\cdot}day$-0.90 $kg/ha{\cdot}day$ TN, 0.03 $kg/ha{\cdot}day$-0.044 $kg/ha{\cdot}day$ for TP.