• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.399-402
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• 2001

After the legal foundation for the Total Load Control System (TLCS) process is embedded in integrated water management counterplan for 4 major river basins (1998), Kyunggido Kwangju City prepared the implementation plan of TLCS at first time. There is little difference between TLCS and TMDL(Total Daily Maxium Loading; U.S.A). TMDL is applied only when mandatory effluent limitations are not stringent enough to attain any water quality standard. But object of TLCS not only attain water quality standard at distributed watershed but also consider development of area at non-distributed watershed. For applying of systematic and consistent TLCS, we need to establish a system integrated watershed and point source, non-point source and assessed massive database easily. Now we are study on applicable possibility of BASINS on Korea, we think that BASINS's tool and many models are more easily apply to TLCS, so we recommend TLCS will be applied using BASINS.

• 한국농공학회지
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• 제42권3호
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• pp.76-88
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• 2000

AGNPS model is applied in this study to analyze the changes of non-point source pollutant according to AMC condition using probable rainfall. Probable rainfall of H-dam area by Gumber's extreme value distribution is computed through frequency analysis for each return period. 35 coarse grids are subdivided into 134 find grids of finite differential network to analyze peak flow soil loss quantity and nutrients of study area and the modified CN estimation equation shows good result about rainfall events-peak flow relationship. And as the consequence of estimation of soil loss quantity for each rainfall event soil loss quantity shows 120%-170% of actual soil loss quantity Regression analysis for the observed and calculated values of flow T-P AMC has an important effect on nutrients concentration of outflow and it if found that the excessive fertilization under AMC III condition may cause eutrophication by nutrients because the range of increase of outflow concentration appears relatively high.

• 한국관개배수논문집
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• 제2권1호
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• pp.10-19
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• 1995

Non-point source pollution due to agricultural chemicals is one of the great concerns from the viewpoint of environmental protection. Scientists have been trying to develop best management practices in agriculture in order to decrease the oater pollution

• 한국환경농학회지
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• 제26권2호
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• pp.107-115
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• 2007

본 연구는 농경지와 농촌마을로부터 발생하여 소하천으로 유입되는 비점오염물질을 경감시키기 위하여 농업간선배수로 끝의 논에서 배수로 물을 관개수로 이용하였을 때 수질정화효과를 살펴보고, 비점오염물질 정화를 위한 효과적인 벼 재배 양식을 탐색하기 위하여 수행하였다. 모든 벼 재배양식에서 하천으로 유입되는 비점오염물질이 정화되는 효과를 확인할 수 있었다. 잡초의 건물량을 포함한 벼 재배양식별 총건물생산능력은 기계이앙재배에서 가장 높았으나, 무경운자연재배와는 차이가 적었고, 비점오염물질인 T-N과 $P_2O_5$, $K_2O$의 흡수량은 기계이앙재배 > 무경운자연재배 > 건답직파재배 순으로 높았다. 벼 전 생육기간동안 비점오염물질의 정화량은 T-N과 T-P, K 모두 무경운자연재배 > 건답직파재배 > 기계이앙재배 순이었는데, 기계이앙에 비하여 무경운자연재배에서 T-N 323, T-P 12, K 183 kg $ha^{-1}$가 더 정화되었으며, 건답직파재배에서는 T-N 68, T-P 0.7, K 16 kg $ha^{-1}$가 더 정화된 결과를 보였다. 기계이앙재배는 건물생산량과 비점오염물질의 흡수량은 가장 많았으나 관개 소요량이 적고 시비에 의하여 비점오염물질의 정화효과는 상대적으로 낮았다. 벼 생육단계별 비점오염물질정화량은 기계이앙재배의 경우 분얼기 > 결실기 > 신장기 순으로 높았으나, 무경운자연재배와 건답직파재배에서는 결실기 > 분얼기 > 신장기 순이었다. 벼 재배양식별 쌀수량은 기계이앙재배의 4,698 kg $ha^{-1}$와 비교하여 무경운자연재배는 13%, 건답직파재배는 15% 감수되었다.

• 한국농공학회논문집
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• 제49권3호
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• pp.79-88
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• 2007

This paper suggests a hierarchial method to select the target sites for the nonpoint source pollution management considering factors which reflect the interrelationships of significant outflow characteristics of nonpoint source pollution at given sites. The factors consist of land slope, delivery distance to the outlet, effective rainfall, impervious area ratio and soil loss. The weight of each factor was calculated by an analytic hierarchy process(AHP) algorithm and the resulting influencing index was defined from the sum of the product of each factor and its computed weight value. The higher index reflect the proposed target sites for nonpoint source pollution management. The proposed method was applied to the Baran HP#6 watershed, located southwest from Suwon city. The Agricultural Nonpoint Pollution Source(AGNPS) model was also applied to identify sites contributing significantly to the nonpoint source pollution loads from the watershed. The spatial correlation between the two results for sites was analyzed using Moran's I values. The I values were $0.38{\sim}0.45$ for total nitrogen(T-N), and $0.15{\sim}0.22$ for total phosphorus(T-P), respectively. The results showed that two independent estimates for sites within the test water-shed were highly correlated, and that the proposed hierarchial method may be applied to select the target sites for nonpoint source pollution management.

• 생태와환경
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• 제45권1호
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• pp.62-71
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• 2012

Lake Doam watershed was surveyed to evaluate non-point source discharge characteristics and discharge load including several water quality parameters in Song Stream from July 2009 to July 2011. Concentrations of water pollutants were high during the rainfall period, especially, SS, TP and COD showed increasing tendencies toward cumulative water discharge but TN did not show much difference. SS, TP and COD had an initial flush effect of over 50 mm rainfall event but there was no clear tendency for rainfalls below that level. Event mean concentration (EMC) regarding the rainy and dry period showed large differences. Especially rainy season EMC (SS, TP, COD) demonstrated an increasingly high tendency. EMCs of COD, SS, TN and TP measured for twelve rain events were as high as 26.1, 866.0, 4.68 and 0.605 mg $L^{-1}$, respectively. COD, SS, TN and TP loadings from the highland agricultural region of the Song Stream watershed were 34,263, 1,250,254, 2,673 and 933 kg $yr^{-1}\;km^{-2}$, respectively, which were relatively higher than the results of other stream systems. Therefore, it is strongly recommended that long-term monitoring and non-point pollution reduction programs for the highland agricultural area to continue. Furthermore, this non-point source pollution loading research acquired from the highland agricultural area could be the base for reassessment.

• 한국농공학회논문집
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• 제65권4호
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• pp.1-10
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• 2023

As a result of climate change, non-point source pollution (NPS) from farmland with the steep slope during the rainy season is expected to have a significant impact on the water system. This study aimed to evaluate the effect of furrow mulching using alfalfa and PAM (Polyacrylamide) materials for each rainfall event, while considering the load characteristics of NPS. The study was conducted in Wanju-gun, Jeollabuk-do, in 2022, with a testbed that had a slope of 13%, sandy loam soil, and maize crops. The testbed was composed of four plots: bare soil (Bare), No mulching (Cont.), Vegetation mulching (VM), and PAM mulching (PM). Runoff was collected from each rainfall event using a 1/40 sampler and the NPS load was calculated by measuring the concentrations of SS, T-N, T-P, and TOC. During farming season, the reduction efficiency of NPS load was 37.1~59.5% for VM and 38.2~75.7% for PM. The analysis found that VM had a linear regression correlation (R²=0.28~0.86, P-value=0.01~0.1) with elapsed time of application, while PM had a quadratic regression correlation (R²=0.35~0.80, P-value=0.1). These results suggest that the selection of furrow mulch materials and the appropriate application method play a crucial role in reducing non-point pollution in farmland. Therefore, further studies on the time-series reduction effect based on the application method are recommended to develop more effective preemptive reduction technologies.

• 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.

• 한국물환경학회지
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• 제37권6호
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• pp.520-530
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• 2021

Multivariate statistical analysis and an environmental hydrological model were applied for investigating the causes of water pollution and providing best management practices for water quality improvement in urban and agricultural watersheds. Principal component analysis (PCA) and cluster analysis (CA) for water quality time series data show that chemical oxygen demand (COD), total organic carbon (TOC), suspended solids (SS) and total phosphorus (T-P) are classified as non-point source pollutants that are highly correlated with river discharge. Total nitrogen (T-N), which has no correlation with river discharge and inverse relationship with water temperature, behaves like a point source with slow and consistent release. Biochemical oxygen demand (BOD) shows intermediate characteristics between point and non-point source pollutants. The results of the PCA and CA for the spatial water quality data indicate that the cluster 1 of the watersheds was characterized as upstream watersheds with good water quality and high proportion of forest. The cluster 3 shows however indicates the most polluted watersheds with substantial discharge of BOD and nutrients from urban sewage, agricultural and industrial activities. The cluster 2 shows intermediate characteristics between the clusters 1 and 3. The results of hydrological simulation program-Fortran (HSPF) model simulation indicated that the seasonal patterns of BOD, T-N and T-P are affected substantially by agricultural and livestock farming activities, untreated wastewater, and environmental flow. The spatial analysis on the model results indicates that the highly-populated watersheds are the prior contributors to the water quality degradation of the river.

• 농촌계획
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• 제24권4호
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• pp.99-119
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• 2018

Unit load factor, which is used for the quantification of non-point pollution in watersheds, has the limitation that it does not reflect spatial characteristics of soil, topography and temporal change due to the interannual or seasonal variability of precipitation. Therefore, we developed the method to estimate a watershed-scale non-point pollutant load using seasonal forecast data that forecast changes of precipitation up to 6 months from present time for watershed-scale water quality management. To establish a preemptive countermeasure against non-point pollution sources, it is possible to consider the unstructured management plan which is possible over several months timescale. Notably, it is possible to apply various management methods such as control of sowing and irrigation timing, control of irrigation through water management, and control of fertilizer through fertilization management. In this study, APEX-Paddy model, which can consider the farming method in field scale, was applied to evaluate the applicability of seasonal forecast data. It was confirmed that the rainfall amount during the growing season is an essential factor in the non-point pollution pollutant load. The APEX-Paddy model for quantifying non-point pollution according to various farming methods in paddy fields simulated similarly the annual variation tendency of TN and TP pollutant loads in rice paddies but showed a tendency to underestimate load quantitatively.