• 도시과학
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• 제10권1호
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• pp.39-48
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• 2021

In this study, to evaluate the characteristics of the pollution in the major inflow tributaries and major environmental facilities in the watershed of Ara waterway, An inflow flow rate measurement and water quality analysis were conducted during dry and rainy seasons. In addition, the flow rate measurement, water quality analysis, and pollutant load at each monitoring point were compared and evaluated. Influx of BOD5, T-P and T-N into the tributaries of the ARA waterway watershed, excluding the Gulpo river watershed, during dry season were only 0.007%, 0.005% and 0.004% respectively of the incoming loads in the entire ARA waterway basin. In addition, it was confirmed that the discharge pollutant loads during rainfall event was about 440 times more for BOD5, about 545 times on T-P, and about 23 times on T-N in comparison to the pollutant loads during the dry days. When the Gulhyeon rubber dam was deflated, the discharged pollutant load during a rainfall was higher than the estimated load at the G7 monitoring point because the deposited pollutants from the upstream riverbed flowed down. Therefore, during a rainy season, it is necessary to manage the influx of high-load water pollutants from the overflow and deflation of the Gulhyun rubber dam as well as to find a strategy to reduce the pollutant loads in the Gulpo river watershed.

• 한국환경과학회지
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• 제18권9호
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• pp.961-970
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• 2009

This paper has attempted to improve the quality of urban environment in terms of the management of urban green tract and suggest a way of coexistence between human and nature by proposing a plan to establish green network using an urban green zone based on 'linear concept' instead of point and plane concepts. The results have turned out as follows: 1. According to current status of forest functions, forest recreation area has reached 39.6%, satisfying citizens' needs. However, the space for living environment is just about 20% with a lack of a green zone. Therefore, it's been necessary to establish green network using roadside trees and take advantage of them as sustainable living space along with existing green tract. 2. With forest in the suburbs and Geumhogang which is the tributary to the Nakdonggang, Sincheon (stream) flows through the downtown. It connects mountains including Waryongsan from the south to the north around Duryu Park and Dalseong Park. Therefore, the water system that passes through Palgongsan (Mt.) and Biseulsan (Mt.) would make it possible to connect with the parks in the downtown. 3. According to this paper, it appears that it's necessary to establish green network through roof or wall greening by focusing on the existing green tract in the urban parks and suburbs and taking advantage of roadside trees and water system.

• 한국조경학회지
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• 제42권1호
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• pp.64-74
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• 2014

생태공원은 자연 자원의 지속 가능한 이용을 활성화하고 대상지를 기반으로 환경 교육을 위한 장소로서 활용될 수 있다. 그러나 생태공원에서 운영되는 생태 체험 프로그램은 이용자들이 직접 체험하고 관찰하는 방식의 교육으로 이용자들이 요구하는 여가편익을 반영하여야 하지만, 이용자들을 대상으로 생태공원에 대한 여가편익을 심층적으로 고찰한 연구는 미비한 실정이다. 이에 본 연구에서는 생태공원을 방문하는 이용자들의 환경태도, 여가편익, 만족도 간의 영향관계를 파악하고자 하였다. 실증적 분석을 위해 서울시에 위치한 길동생태공원, 여의도 샛강 생태공원의 이용자를 대상으로 총 282부의 유효한 설문지를 수집하였다. 통계적 분석결과, 생태공원을 방문하는 이용자들의 환경에 대한 태도가 긍정적일수록 이용자들의 생태공원 방문시 자연친화적 경험에 대한 교육과 전문적인 지식 확대에 대한 여가편익에 높은 기대를 하고 방문하는 것으로 나타났다. 생태공원을 통해 이용자들이 원하는 여가편익이 방문하기 전 기대와 방문 후 여가편익의 차이 분석을 실시한 결과, 이용자들이 생태공원을 방문할 가치가 있었다고 느꼈으나, 교육적인 측면의 여가편익에서는 방문 전 기대보다 불충분한 만족을 느끼고 있음을 나타냈다. 또한, 방문 후 여가편익은 생태공원 전체 만족도에 긍정적인 영향을 주고, 긍정적인 환경에 대한 태도는 전체 방문만족도에 영향을 미치지 못하는 것으로 나타났다. 이는 현재 우리나라의 생태공원이 일반 공원과 차이를 보이지 않고, 공원을 방문하는 이용자들도 차이를 느끼지 못하기 때문이라 판단된다. 이러한 연구결과는 향후 생태공원 이용자들이 요구하는 여가편익인 자연친화적 경험과 생태교육의 다양성을 중심으로의 일반공원과의 차별적인 관리가 필요하다.

• 한국환경과학회지
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• 제23권3호
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• pp.433-445
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• 2014

The objective of study was to analyze seasonal and inter-annual patterns of water chemistry of Miho Stream watershed during 2004 - 2007 along with some influences of tributaries and summer monsoon on the stream water quality. For the study, eight physico-chemical parameters such as nitrogen, phosphorus, BOD, COD and chlorophyll-a (CHL) etc. were analyzed in relation to spatial and temporal variability of seven sampling sites of the mainstream and some tributaries in the watershed. In the upstream reach, Mean of BOD, COD and TP averaged 3.2 mg/L, 6.5 mg/L and $186{\mu}g/L$, respectively, indicating an eutrophic conditions as a III-rank in the stream water quality criteria from the Ministry of Environment, Korea(MEK). The eutrophic water was due to a combined effect of Chiljang tributary with high nutrients ($TP=844{\mu}g/L$, TN=8.087 mg/L) and the point sources from some wastewater treatment plants. In the meantime, BOD, TN, and TP in the downstream reach were about > 1.2-1.5 folds than the values of the midstream reaches. This was mainly attributed to effluents of nutrient rich-water (mean TN: 11.980 mg/L) from two tributaries of Musim Stream and Suknam Stream, which is directly influenced by nearby wastewater disposal plants. Seasonal analysis of water chemistry showed that summer monsoon rainfall was one of the important factors influencing the water quality, and water quality had a large spatial heterogeneity during the rainfall period. In the premonsoon, BOD in the downstream averaged $6.0{\pm}2.47mg/L$, which was 1.4-fold greater than the mean of upstream reach. Mean of CHL-a as an indicator of primary productivity in the water body, was > 2.2 - 2.9 fold in the downstream than in the upstream, and this was a result of the high phosphorus loading from the watershed. Overall, our data suggest that some nutrient controls in point-source tributary streams are required for efficient water quality management of Miho Stream.

• 생태와환경
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• 제55권4호
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• pp.320-329
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• 2022

Urban areas in watersheds increase the impervious surface, and agricultural areas deteriorate the water quality of rivers due to the use of fertilizers. As such, anthropogenic land use affects the type, intensity and quantity of land use and is closely related to the amount of substances and nutrients discharged to nearby streams. Riparian vegetation reduce the concentration of pollutants entering the watershed and mitigate the negative impacts of land use on rivers. This study analyzes the data through correlation analysis and regression analysis through point data measured twice a year in spring and autumn in 21 selected damaged tributary rivers within the Han River area, and then uses a structural equation model to determine the area land use. In the negative impact on water quality, the mitigation effect of riparian vegetation was estimated. As a result of the correlation analysis, the correlation between the agricultural area and water quality was stronger than that of the urban area, and the area ratio of riparian vegetation showed a negative correlation with water quality. As a result of the regression analysis, it was found that agricultural areas had a negative effect on water quality in all models, but the results were not statistically significant in the case of urban areas. As a result of the model estimated through the structural equation, BOD, COD, TN, and TP showed a mitigation effect due to the accumulation effect of river water quality through riparian vegetation in agricultural areas, but the effect of riparian vegetation through riparian vegetation was found in urban areas. There was no These results were interpreted as having a fairly low distribution rate in urban areas, and in the case of the study area, there was no impact due to riparian forests due to the form of scattered and distributed settlements rather than high-density urbanized areas. The results of this study were judged to be unreasonable to generalize by analyzing the rivers where most of the agricultural areas are distributed, and a follow-up to establish a structural equation model by expanding the watershed variables in urban areas and encompassing the variables of various factors affecting water quality research is required.

• 한국물환경학회지
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• 제22권6호
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• pp.1060-1067
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• 2006

Water quality in the Daecheong reservoir has been deteriorated by algal bloom due to nutrient supply from the upstream of the Daecheong reservoir after heavy rainfall. Algal bloom is propagated from eutrophicated tributary into the main body of the reservoir according to the hydrological conditions. This study is aimed to estimate the water current and temperature effect by the simulation of dam spill flow control using water quality model, CE-QUAL-W2 in 2003. Water current was resulted in nutrient transport from upstream of main reservoir and nutrients were delivered up to downstream by fast water velocity. Algal blooms occurred in stagnate zone of reservoir downstream as the current of downstream was retarded according to dam outflow control. Consequently water balance in stagnate zone triggered a rise of water temperature in summer. It affected algal bloom in the embayment of the reservoir. The simulation result by outflow control scenarios showed that spill flow augmentation induced in water body instability of stagnate zone so that water temperature declined. It could be suggested that outflow control minimize algal bloom in the downstream in the flooding season as long as water elevation level is maintained properly.

• 환경영향평가
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• 제13권4호
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• pp.153-164
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• 2004

An integration study of time-variable small watershed and stream models (USEPA's SWMM and WASP5) was performed for impact assessment of urbanization on water environment. The study area, the Kyoungan Stream, the tributary of Paldang Lake, was divided into 111 subbasins, based on the topographic condition, land use, and drainage system. RUNOFF block of SWMM was applied to estimate runoff flow and quality. EXTRAN block computed daily and hourly flow according to simulated runoff flow, water supply, and drainage data. SWMM was connected to WASP5 by transforming output file of SWMM into input file of WASP5. The nonpoint source loads and flow data of SWMM were imported to WASP5. The stream was divided into 45 segments based on the watershed delineation. The study included three water quality parameters, BOD, TN, and TP. The validate models were used to examine the impact of urbanization on stream flow and water quality.

• 상하수도학회지
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• 제25권6호
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• pp.825-837
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• 2011

Seonakdong river consists of stagnant sections whose flowrate is controlled by the Daejeo and Noksan gates. As a result, there is not a minimum flow during normal times. The Daejeo and Noksan gates are located at the upstream head and the downstream end of Seonakdong river, respectively. Seonakdong river is an estuarine tributary of Nakdong river, which is a reservoir-like river used for agricultural irrigation, with the gate at the estuary of the river to prevent the intrusion of saline. Since the construction of the water gates, the water quality of the river has become degraded. This could also be due to the internal loading of pollutants, especially nutrients, from the sediments of the river because of the elongated detention time by the water gates. This study was thus conducted for the purpose of evaluating the current hydrologic-cycle system and providing measures for the rehabilitation of the hydrologic cycle. In this research, the daily outflow in Seonakdong River was simulated using the SWAT and SWMM models, and the water quality concentration including BOD, SS, TN, and TP were analyzed. The possibility of the application of SWAT-SWMM hybrid simulation was determined through the verification of both models. The error analysis shows that the results of both SWAT and SWAT-SWMM simulations make good agreements with those of field observations. For the single simulation results of SWAT, $R^{2}$ and NSE are 0.758, 0.511, respectively. For the hybrid simulation results of SWAT-SWMM, those are 0.880, 0.452, which means that the hybrid simulation can give more accurate results for the watershed where both the agricultural and urban areas exist.

• 대한공간정보학회지
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• 제16권1호
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• pp.13-21
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• 2008

본 논문에서는 금강수계의 미호천을 대상으로 GIS를 이용, 2010년을 대상으로 장래수질을 예측하였다. 오염총량관리 기본계획에서 제시된 자료를 기반으로 미호천으로 유입되는 지류별 수계에 대하여 재계산하여 각 수계별 오염부하량을 산정하였으며 이들 정보를 활용하여 지류별 농도를 계산한 다음 미호천의 수질모의를 실시하였다. 수질모의는 대표적인 하천수질 모형인 Qual2E 모형을 사용해서 BOD, TN, TP 등의 대표적인 수질인자에 대한 모의를 실시 하였다. 수계별 오염부하량을 산정한 결과 도시지역을 포함한 무심천 및 보청천의 부하량이 높게 나타남을 알 수 있었고 미호천 전체 수질은 청주 하수처리장의 영향을 직접적으로 받는 것으로 나타났다. 대상유역에서의 효율적 수질관리와 오염총량제에서 제시한 목표수질을 달성하기 위해서는 하수처리장의 고도처리화가 먼저 달성되어야 함을 알 수 있었고, 그 외에도 무심천으로 공급되는 농업용수의 유량을 증가시켜 이를 수질희석의 용도로 사용하는 방안에 대해서 모의를 실시함으로써 수질기준을 만족할 수 있는 적정유량을 산정하여 제시하였다.

• 한국물환경학회지
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• 제27권5호
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• pp.670-679
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• 2011

Chlorophyll-a is a major water quality indicator for an algal bloom in streams and lakes. The purpose of the study is to estimate chlorophyll-a concentration in tributaries of the Seonakdonggang by an artificial neural network (ANN). As the tributaries are ungauged streams, a watershed runoff and quality model was used to simulate water quality parameters. The tributary watersheds include urban area and thus Storm Water Management Model (SWMM) was used to simulate TN, TP, BOD, COD, and SS. SWMM, however, can not simulate chlorophyll-a. The chlorophyll-a series data from the tributaries were estimated by the ANN and the simulation results of water quality parameters using SWMM. An assumption used is as follows: the relation between water quality parameters and chlorophyll-a in the tributaries of the Seonakdonggang would be similar to that in the mainstream of the Seonakdonggang. On the assumption, the measurement data of water quality and chlorophyll-a in the mainstream of the Seonakdonggang were used as the learning data of the ANN. Through the sensitivity analysis, the learning data combination of water quality parameters was determined. Finally, chlorophyll-a series were estimated for tributaries of the Seonakdonggang by the ANN and TN, TP, BOD, COD, and temperature data from those streams. The relative errors between the estimated and measured chlorophyll-a were approximately 40 ~ 50%. Though the errors are somewhat large, the estimation process for chlorophyll-a may be useful in ungauged streams.