• Korean Journal of Ecology and Environment
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• v.47 no.1
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• pp.13-23
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• 2014

To obtain optimum filter media, configuration method and greenhouse wastewater loading in small-scale constructed wetlands (CWs) for treating greenhouse wastewater, the apparatuses were constructed with 4 kinds of combined systems such as vertical flow (VH)-Horizontal flow (HF), HF-VH, HF-VF-HF, VF-HF-HF CWs. The efficiencies of pollutants in greenhouse wastewater were investigated in various CWs under different filter media, configuration methods and agricultural water loading. Removal rates of pollutants under different filter media were in the other of coarse sand>broken stone${\fallingdotseq}$calcite${\fallingdotseq}$mixed filter media for COD, broken stone>mixed filter media>coarse sand>calcite for T-N, and calcite>mixed filter media>broken stone>coarse sand for T-P. The removal rates of pollutants in HF-VH-HF CWs at different configuration methods were higher than those in other configuration methods. The removal rates of pollutants were higher in the order of $150L\;m^{-2}day^{-1}{\fallingdotseq}300L\;m^{-2}day^{-1}$ > $600L\;m^{-2}day^{-1}$ under different greenhouse wastewater loading. Therefore, optimum configuration method was HF-VH-HF CWs, the optimum filter media was mixed filter media (coarse sand : broken stone : calcite=1 : 1 : 1), and the optimum greenhouse wastewater loading was $300L\;m^{-2}day^{-1}$ in HF-VH-HF CWs.

• 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.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.481-488
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• 2006

The field scale experiment was performed to examine the performance of the constructed wetland for nonpoint source (NPS) pollution loading reduction. Four sets (0.88 ha each) of wetland and pond system were used. After three growing seasons of the wetland construction, plant coverage increased to about 90% even without plantation from bare soil surfaces at the initial stage. During the start up period of constructed wetlands, lower water levels should be maintained to avoid flooding newly plants, if wetland plants are to start from germinating seeds. The average removal rate of $BOD_5$, TSS, T-N and T-P during the first two years was 5.6%, 46.6%, 45.7%, and 54.8%, respectively. The $BOD_5$ removal rate was low and it might be attributed to the low influent concentration. The early stage of wetland performance demonstrated the effectiveness of water quality improvement and was satisfactory for treating polluted stream waters. From the first-order analysis, T-P was virtually not temperature dependent, and $BOD_5$ and TSS were more temperature dependent than T-N. A pond-wetland system was more effective than a wetland-pond or a wetland alone system in water quality improvement, particularly to reduce T-P. Overall, the wetland system was found to be an adequate alternative for treating a polluted stream water with stable removal efficiency and recommended as a NPS control measures.

• Journal of Environmental Health Sciences
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• v.39 no.5
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• pp.474-481
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• 2013

Objectives: This study was conducted to investigate the application of microbial fuel cells (MFCs) to the wastewater treatment systems employed in the Living Building Challenge. Methods: I reviewed a range of information on decentralized wastewater treatment technologies such as composting toilets, constructed wetlands, recirculating biofilters, membrane bioreactors, and MFCs. Results: The Living Building Challenge is a set of standards to make buildings more eco-friendly using renewable resources and self-treating water systems. Although there are various decentralized wastewater treatment technologies available, MFCs have been considered an attractive future option for a decentralized system as used in the Living Building Challenge. MFCs can directly convert substrate energy to electricity with high conversion efficiency at ambient and even at low temperatures. MFCs do not require energy input for aeration if using open-air cathodes. Moreover, MFCs have the potential for widespread application in locations lacking water and electrical infrastructure Conclusions: This paper demonstrated the feasibility of MFCs as a novel decentralized wastewater treatment system employed in the Living Building Challenge.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.3
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• pp.1-7
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• 2007

For waste water treatment, artificial wetland was constructed in 1998. The size of artificial wetland is 20m${\times}$200m, with sand and gravel as media and Phragmites japonica was implanted. The removal rate of BOD, TN, and TP were 86%, 33% and 25% from June 2004 to November 2005 respectively, while those were 88%, 38% and 55% in 1999. Organic materials and nitrogen compounds are still effectively removed, after 6 years of construction, but the removal efficiency of phosphorus compounds is reduced. So for sustaining of artificial wetland as waste water treatment system, the removal efficiency of phosphorus compounds must be elevated.

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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• pp.199-203
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• 2003

This study was carried out to investigate the removal of 2,4,6-trinitrotoluene, nutrients such as nitrogen, phosphorous compounds in the wetland microcosms. Microcosm study indicated that TNT nutrients were more lastly reduced in the anaerobic condition. The major reductive transformation products included 2,4diamino-6-nitrotoluene (2,4-DANT) 2,6diamino-4-nitrotoluene (2,6-DANT) 4diamino-2,6-nitrotoluene (4-ADNT) 2diamino-4,6-nitrotoluene (2-ADNT). The experimental results for nitrogen removal showed that denitrification kom NO$\sub$3//$\^$-/ to NH$_3$ was dominant process at the bottom of marsh, but nitrification from NH$_3$ to NO$\sub$3//$\^$-/ was dominant on the top of marsh.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.4
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• pp.37-46
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• 1999

Field experimnet of constructed wetland for rural wastewater treatment was performed from July 1998 to April 1999 including winter to examine the seasonal effect on the wetland performance. The system worked without freezing even under $-10^{\circ}C$ of air temperature as long as watewater was flowing. BOD removal rates varied in similar pattern as the air temperature, and winter performance was relatively lower than that in the growing season. However, removing performance during winter was still significant, and BOD removal rates were almost the the same as in the growing season. SS removal rate was relativelyless affected by temmperature, but lower decay rate during the winter can result in accumulation of the SS in the system, which releases constituents in the next spring and can affect whole system performance. The winter removal rates of nutrients like T-N and T-P were decreased about half compared to the growing season and low temperature. To maintain stabilized wetland performanced including winter time, supplying minimum heating for plants could be an alternative in field application. Experimental data was compared with NADB(North Americal Wetlands for Water Quality treatment database), and general performance of the system was within the reasonable range. The pollutant loading and effluent concentration of the experimented system were in high margin. Base on the experiment and databases, the required effluent water quality could be achieved if loading rate adjusted as ilulstrated in the database.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.6
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• pp.137-148
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• 2008

There have been many cases of using wetlands as an alternative in controlling stormwater, treating mining leachate, and agricultural discharge, and so on, recently. The reality is, however, that the wetlands are not properly applicable because of the lack of enough longterm data for wetlands due to the difficulty of long-term monitoring. Therefore, this study tries to analyze the storage of Upo, Mokpo, Sajipo, and Jjokjibeul in Topyeong watershed using SWAT(Soil and Water Assessment Tool) model, one of the long-term runoff hydrologic model, for the purpose of generating the long-term data and analyzing the hydrologic behavior of wetlands based on the generated data. Also, the changes in runoff at the outlet are analyzed after applying the simulation of constructing washland in Topyeong watershed and the storage in Upo is analyzed. The result shows that the runoff at the outlet of the watershed is decreased in rainy season from July to August and increased in dry season from December to February. In addition, the analysis of Upo storage concludes that Upo can be influenced by the construction of the washland. The duration curve of washland is then analyzed in order to evaluate the wetland's sustainability in terms of washland and it appears that the runoff of washland is simulated to be less than that of the existing wetland. Moreover, runoffs of some washlands are simulated to be less even in wet season. These results lead to the fact that there should be further hydrologic management for constructed washland. Then, the changes in loads (TN and TP) because of constructing washland are analyzed. The result shows that the loads are reduced because of the construction. Also, the changes in loads due to the construction of buffer strips are analyzed to compare the load reductions caused by a washland. Finally, REMM model, a riparian management model, is applied to overcome the hydrologic ambiguousness of SWAT model, and then, the SWAT model results are compared to those of REMM.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.317-324
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• 2012

To reduce non-point source pollutants in Juam Lake eco-wetlands, purification efficiencies of pollutants were investigated at three different systems. The constructed wetlands (CWs) consisted of A system, B system and C system. A system consisted of $1^{st}$ free water surface (FWS) CW, $2^{nd}$ FWS CW, $3^{rd}$ FWS CW, $4^{th}$ subsurface flow (SSF) CW and $5^{th}$ SSF CW. B system consisted of $1^{st}$ FWS CW, $2^{nd}$ FWS CW, $3^{rd}$ FWS CW, $4^{th}$ FWS CW and $5^{th}$ SSF CW. C system consisted of $1^{st}$ FWS CW, $2^{nd}$ FWS CW, $3^{rd}$ FWS CW, $4^{th}$ FWS CW and $5^{th}$ SSF CW. The concentrations of BOD, COD, SS, T-N and T-P in inflow ranged 0.20 ~ 0.91, 1.24 ~ 8.00, 0.60 ~ 8.60, 0.04 ~ 2.50 and $0.001{\sim}0.685mg\;L^{-1}$ from March to October in 2011, respectively. Removal rates of BOD, SS, T-N and T-P were high in Autumn, Spring, Spring and Summer, respectively. In A system, $1^{st}$ FWS CW, $2^{nd}$ FWS CW and $3^{rd}$ FWS CW were dominated by Leersia oryzoides. In B system, $1^{st}$ FWS CW, $3^{rd}$ FWS CW and $4^{th}$ FWS CW were dominated by Leersia oryzoides. In C system, $2^{nd}$ FWS CW and $3^{rd}$ FWS CW were dominated by Nymphaea teragona.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.21-37
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• 2010

The abiotic factors and the vegetation naturalness of the 13 tributary wetlands around Namgang-River were assessed to investigate the present state and to present the conservation counter plan for the wetland ecosystem of the tributaries. Assessment indices for the abiotic factors were estimated based on the dominant land use types of the riparian zone, ecological function of the upper levee, levee slope structure, artificiality and utilization intensity of the waterfront, artificiality of the revetment structure, diversity of the substrate, and severance of the transverse. The assessment index of Omi-cheon is the highest among 13 tributaries. The second was Banseong-cheon and third was Hyangyang-cheon, followed by Nabul-cheon and Yeongcheon-gang and Sugok-cheon, Jungchon- cheon, and Daegok-cheon in their order and Munsan-cheon got the lowest assessment index. Assessment indices for the vegetation naturalness were estimated based on the vegetation diversity, exotic species dominance, annual herb dominance, naturalness and peculiarity of the vegetation, and species diversity. The assessment index of Omi-cheon is the highest among 13 tributaries. The second was Sugok-cheon and third was Banseong-cheon, followed by Yeongcheon-gang, Jungchon- cheon, Jinae-cheon, Nabul-cheon, and Jisu-cheon in their order, and Yonga-cheon got the lowest assessment index. The grades of the stream naturalness were estimated based on the the naturalness indices for the abiotic factors and the vegetation naturalness. The grades of Omi-cheon is the highest among 13 tributaries as the grade I. Those of Banseong-cheon, Sugok-cheon, Yeongcheon-gang, Nabul-cheon and Jungchon-cheon, Hyangyang-cheon, Jinae-cheon, Jisu-cheon, Daegok-cheone, and Munsan-cheon and Doksan-cheon were grade II in their order, and Yonga-cheon got the lowest as the grade III. It was suggested that restoration of the simple and flat substrate, create the natural vegetation on the levee slope constructed with concrete or stone wall, and rehabilitation of the eco-bridge were demanded to improve the grades of the stream naturalness through the restoration of the tributaries for the diverse aquatic wildlife, high vegetation diversity and species diversity with the vegetation consisted of perennial herbs and trees.