• Journal of Wetlands Research
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• v.13 no.2
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• pp.199-208
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• 2011

Scarcity of water worldwide, increasing greenhouse gas emissions, increased energy consumption due to the Earth is threatened. Existing in the process of urban planning and development of forests, rivers and other natural ecosystems have been destroyed and that there was increased impervious pavement. Impervious pavement increase water circulation system to destroy the natural and urban water retention, infiltration and decreased evaporation. Nonpoint source pollution(NPS) occurs when rainfall impervious pavement and appeal directly to the river water inflow is adversely impacts of the situation. In this study, rainfall occurs impervious pavement NPS pollution reduction and temperature increase due to the increase in urban areas, and to solve heat island phenomenon is to develop small HSSF constructed wetland technology. The small HSSF constructed wetland sedimentation, filtration, adsorption, absorption by vegetation, including such mechanisms. Techniques for verification of the pilot-scale test was conducted. In the future domestic urban heat island phenomenon and restore the natural water cycle for the facilities will be used as a basis to develop.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.363-366
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• 2009

환경부는 2000년대에 들어 수질오염총량관리제의 정책 도입으로 하천과 호소의 수질개선에 노력을 기울이고 있으며, 개발사업과 관련된 비점오염원에서의 비점오염물질 관리를 요구하고 있다. 포장율이 높은 토지이용 변경사업, 즉 교량, 도로, 고속도로 등의 개발 사업은 특히 비점오염원 관리를 요구하고 있다. 그러나 현재 국내에 적용되고 있는 비점오염저감시설은 대부분 소규모 장치형 시설이며, 유지관리가 어렵고 저감효율이 낮은 단점이 있다. 최근에는 장치형 시설보다 생태친화적인 기능을 가지며 녹색 및 생태축 연결이 가능한 자연형 시설을 적용하는 방향으로 정책이 변화하고 있다. 이러한 조건과 더불어 기후변화에 능동적으로 대응하기 위해서는 교량의 경우 소규모 인공습지를 조성하여 녹색축 연결, 비점오염원 관리가 바람직하다. 따라서 본 연구는 도로와 교량의 녹색축을 연결하고 비점오염물질을 저감할 수 있는 소규모 HSSF 인공습지를 개발하고자 한다. 본 연구를 통해 개발된 소규모 HSSF 인공습지는 입자상 오염물질 제거를 위한 침강지, 용존성 및 미립자의 제거를 위한 습지부로 구성되어 있으며, 녹색축 및 생태공간 확보를 위한 습지의 식생부분이 존재하고 있다. 특히 본 기술은 교량내에서 처리하는 site control 방식으로 외부 유도를 통한 처리기술이 아니기에 비용경제적으로 효율성을 가지고 있다.

• Journal of Wetlands Research
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• v.13 no.3
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• pp.455-463
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• 2011

Conventional construction technologies have been continually applied without consideration of its impact to the environment. This resulted to various problems including the negative responses of local citizens that regarded some constructed facilities as aversive facilities causing environmental and hydraulic problems in the urban area, etc. To prevent these problems, therefore, alternative methods should be undertaken. A new approach termed "Low Impact Development (LID)" technology is currently adapted in developed countries around the world. This study aims to investigate the efficiency of the developed small constructed wetland (SCW) with horizontal subsurface flow as a LID technique applicable in urban areas. Two test-bed facilities were constructed and monitoring had been conducted between July 2010 and June 2011. Based on the findings, the removal efficiencies achieved for TSS, $COD_{Cr}$, TN, TP, Total Fe, Total Pb for the SCW-1 were 66, 53, 46, 55, 67 and 50%, respectively. On the other hand, the SCW-2 attained 82, 62, 51, 48, 74 and 42% efficiency for TSS, $COD_{Cr}$, TN, TP, Total Fe, Total Pb, respectively. The results indicated that the removal of particulate matter and heavy metals which are considered as main pollutants from stormwater runoff in urban areas was satisfactory in the system. Therefore, the test-beds proved to be appropriate for the treatment of pollutants in urban landuses such as road, parking lot, etc. The results of this study can contribute to the conservation of aquatic ecosystems and restoration of natural water cycle in the urban areas.

• Journal of Wetlands Research
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• v.13 no.2
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• pp.231-242
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• 2011

Recently, the green spaces in the urban areas were greatly reduced due to urbanization and industrialization. As urban structures such as roads and buildings are built, the amount of impervious area within a watershed increases. High impervious surfaces are the common causes of high runoff volumes as the soil infiltration capacity decreases and the volume and rate of runoff increase thereby decreasing the groundwater recharge. These effects are causing many environmental problems, such as floods and droughts, climate change, heat island phenomenon, drying streams, etc. Most cities attempted to reduce sewer overflows by separating combined sewers, expanding treatment capacity or storage within the sewer system, or by replacing broken or decaying pipes. However, these practices can be enormously expensive than combined sewer overflows. Therefore, in order to improve these practices, alternative methods should be undertaken. A new approach termed as "Low Impact Development (LID)" technology is currently applied in developed countries around the world. The purpose of this study was to effectively manage runoff by adopting the LID techniques. Small Constructed Wetland(Horizontal Subsurface Flow, HSSF) Pilot-scale reactors were made in which monitoring and experiments were performed to investigate the efficiency of the system in removing pollutants from runoff. Based on the results of the Pilot-plant experiments, TSS, $COD_{Cr}$, TN, TP, Total Pb removal efficiency were 95, 82, 35, 91 and 57%, respectively. Most of the pollutants were reduced after passing the settling tank and the vertical filter media. The results of this study can contribute to the conservation of aquatic ecosystems and restoration of natural water cycle in the urban areas.

• Ecology and Resilient Infrastructure
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• v.1 no.1
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• pp.25-28
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• 2014

Constructed wetlands have widely been employed to improve water quality, but only a few studies have assessed removal efficiencies of cations in pond-type and marsh-type wetlands comparatively. This study conveys removal efficiencies of cations in those types of wetlands. High removal efficiencies of $NH_4{^+}$, $K^+$, $Mg^{2+}$ were observed, which appeared to be related to plant uptake and soil absorption. In contrast, release of $Ca^{2+}$ was distinctive in pond-type wetland of which mechanism is yet to be revealed.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.394-394
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• 2021

이상기후로 인한 강우패턴의 변화는 상류 유역에서의 토양 유실, 비점오염물질의 발생을 가속화시켜 하류 수계의 수질 및 수생태 건강성에 악영향을 미치고 있다. 낙동강 수계에 위치한 내성천 유역에서는 토양 침투율이 높은 토양군으로 구성되어 있어, 강우 시 유출량 및 유사유출량의 비율이 높아 비점오염 저감을 위한 대책 수립의 중요성이 지속적으로 제기되어 왔다. 특히, 내성천 유역 내 상류에 위치한 토일천 및 낙화암천 소유역에서는 다양한 영농활동과 대규모 및 소규모 축사의 영향으로 강우 시 다양한 비점오염물질이 많이 발생하고 있다. 하류 하천에서의 수질을 효율적으로 개선하기 위해서는 비점오염 발생량이 높은 상류 소유역을 대상으로 적절한 최적관리기법 선정과 이에 대한 정량적인 평가 방법이 필요하다. 최근 식생여과대, 침사지 등과 같은 다양한 최적관리기법 중 인공습지에 대한 점오염원 및 비점오염물질 처리 효과가 국내·외 여러 모니터링 연구를 통해 증명되었다. 그러나 아직까지 유역 내 다양한 토양 및 토지이용상태와 그리고 오염원 유출 특성을 고려하여 인공습지의 조성에 따른 유역단위에서의 수질 개선 효과를 정량적으로 분석한 연구는 미비한 실정이다. 이에 본 연구에서는 장기 강우-유출 유역단위 모형인 SWAT(Soil and Water Assessment Tool) 내 인공습지 모의가 가능하도록 모형 소스코드를 수정하였으며, 내성천 상류 소유역(토일천, 낙화암천)에 위치한 인공습지 조성 전후에 따른 유역 말단에서의 유사 및 비점오염물질의 저감 효율을 비교 분석하였다. 향후 본 연구의 결과는 내성천 유역을 대상으로 인공습지를 통한 유사 및 비점오염 저감 대책 수립 시 기초자료로 활용될 수 있을 것이라 사료된다.

• Ecology and Resilient Infrastructure
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• v.3 no.2
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• pp.100-109
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• 2016

Low impact development (LID) facilities are established for the purpose of restoring the natural hydrologic cycle as well as the removal of pollutants from stormwater runoff. Improved efficiency of LID facilities can be obtained through the optimized interaction of their major components (i.e., plant, soil, filter media, microorganisms, etc.). Therefore, this study was performed to evaluate the performances of LID facilities in terms of runoff and pollutant reduction and also to provide an optimal maintenance method. The monitoring was conducted on four LID technologies (e.g., bioretention, small wetlands, rain garden and tree box filter). The optimal SA/CA (facility surface area / catchment area) ratio for runoff reduction greater than 40% is determined to be 1 - 5%. Since runoff reduction affects the pollutant removal efficiency in LID facilities, SA/CA ratio is derived as an important factor in designing LID facilities. The LID facilities that are found to be effective in reducing stormwater runoff are in the following order: rain garden > tree box filter > bioretention> small wetland. Meanwhile, in terms of removal of particulate matter (TSS), the effectiveness of the facilities are in the following order: rain garden > tree box filter > small wetland > bioretention; rain gardens > tree box filter > bioretention > small wetland were determined for the removal of organic matter (COD, TOC), nutrients (TN, TP) and heavy metals (Cu, Pb, Cd, Zn). These results can be used as an important material for the design of LID facilities in runoff volume and pollutant reduction.

• Journal of Wetlands Research
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• v.25 no.2
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• pp.132-144
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• 2023

The use of constructed wetlands (CWs) to sequester carbon has been a topic of interest in recent studies. However, CWs have been found to be both carbon sinks and carbon sources, thus leaving uncertainties about their role in carbon neutrality initiatives. To address the uncertainties, a bibliometric and comprehensive review on carbon sequestration in CWs was conducted. Upon forming various scripts using CorText Manager, it was found that a majority of the studies focused on the effectiveness of CWs to remove nutrients, particularly nitrogen. The results of the comprehensive review revealed that high carbon concentrations and carbon sequestration rates in CW soils are dependent on the vegetation types used, the ages of the CWs, and the organic content of inflow water entering the CWs. The Typha genus was the most dominant plant genus used in the CWs from the reviewed studies and was associated with the highest carbon sequestration rates documented in this review study. Furthermore, the relatively high ability of tree species, in comparison to emergent plants, to sequester carbon was observed. Therefore, incorporating tree species into CW designs and adding them to emergent plants is seen as a potential breakthrough approach to improve the ability of CWs to sequester carbon and ultimately contribute to mitigating climate change.

• Journal of Wetlands Research
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• v.18 no.3
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• pp.324-329
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• 2016

Constructed wetlands are widely applied in urban and rural areas for various purposes such as pollutants reduction, acquisition of eco-spaces and habitats, flooding reduction, acquisition of water resources and environmental education. Since the design of constructed wetlands utilizes ecosystems, special consideration must be given to ecological mechanisms, environmental mechanisms and hydrological mechanisms. To ensure the sustainable functionality of constructed wetlands, it is necessary to achieve stable flow rate and velocity, and remove sediments to ensure sufficient space for detention. To enhance the efficiency of constructed wetland sedimentation basins, this study determined the optimal position for baffle installation, and applied Computational Fluid Dynamics (CFD) to the cross-sectional design of wetlands. CFD analysis revealed that the decrease in flow velocity with baffle installation enhanced the efficiency of sedimentation of particulate matters. Vertical baffles had higher sedimentation efficiency than those with an inclined angle. When vertical baffles were installed in the sedimentation basin of a hybrid constructed wetland to reduce non-point source pollutants in urban areas, the average flow velocity within the basin decreased by 10~30%, while the sedimentation efficiency improved by 1.3~1.5 times. The application of CFD to constructed wetlands is expected to improve the cost efficiency of designing hybrid constructed wetlands with high removal efficiency.

• Korean Journal of Environmental Agriculture
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• v.28 no.3
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• pp.258-265
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• 2009

To develop environmentally friendly constructed wetlands(CWs) for treating domestic sewage which was produced in farming and fishing village, the efficiency of water treatment at different ventilation systems in the vertical bed, depths of horizontal bed, and sewage loads was investigated. In the vertical bed, BOD and COD by duplex ventilation system were lower than those by single ventilation system. But T-N and T-P concentrations by both ventilation systems in the vertical bed were little different. In the horizontal bed, BOD, COD, T-N and T-P in 1.0 m and 1.3 m depths were little different. To reduce the CWs' area and to improve the pollutant removal efficiencies, the optimum depth of horizontal bed was 1.3 m. In single and duplex ventilation CWs, the removal rate of BOD, COD, SS, T-N and T-P decreased slightly with the sewage load increases. In same sewage load conditions, the removal rates of BOD, COD, SS, T-N and T-P by duplex ventilation CWs were higher than those by single ventilation CWs. In summary, to effectively treat domestic sewage from farming and fishing village, the optimum constructed wetlands would be the duplex ventilation CWs.