• Title/Summary/Keyword: Gyu-Dong Choi

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Evaluation of Possibility of Water Plant Wastes in Composting for Agricultural Recycling (수생식물 고사체의 농업적 재활용을 위한 퇴비화 가능성 평가)

  • Choi, Ik-Won;Seo, Dong-Cheol;Kang, Se-Won;Seo, Young-Jin;Lee, Sang-Gyu;Kang, Seog-Jin;Lim, Byung-Jin;Lee, Jun-Bae;Heo, Jong-Soo;Cho, Ju-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.2
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    • pp.248-252
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    • 2012
  • To evaluate the possibility of water plant wastes in composting for agricultural recycling, Phragmites communis (PHRCO), Typha orientalis (TYHOR) and Zizania latifolia (ZIZLA) were used as a compost materials. In composting basin, cumulative oxygen consumptions of the compost used by water plant wastes were rapidly increased at the early stage and slightly decreased in around 15 days. Cumulative oxygen consumptions under different water plant wastes were higher in the order of TYHOR > ZIZLA > PHRCO. Temperature changes during composting process were rapidly increased at the early stage and then slowly decreased to $30{\sim}40^{\circ}C$. The maximum temperatures were higher in the order of ZIZLA ($72.2^{\circ}C$ at 11 days after starting composting) > TYHOR ($70.2^{\circ}C$ at 10 days after starting composting) > PHRCO ($66.5^{\circ}C$ at 7 days after starting composting). Oxygen consumptions at maximum temperature were higher in the order of TYHOR ($12,485mg\;O_2\;kg^{-1}$) > ZIZLA ($12,400mg\;O_2\;kg^{-1}$) > PHRCO ($9,340mg\;O_2\;kg^{-1}$). Organic matter contents, moisture contents and OM/N rates in the compost ranged 39.5~44.8%, 29.6~35.6% and 27.9~32.9, respectively. Considering that water plant waste can supply some of the nutrient requirements of crops and is a valuable fertilizer.

Evaluation of Aquatic Ecological Efficiency in Juam Lake Eco-wetlands for Reducing Non-point Source Pollutants (비점오염물질 저감을 위한 주암호 생태습지의 수생태학적 효율 평가)

  • Lee, Sang-Gyu;Seo, Dong-Cheol;Choi, Ik-Won;Kang, Se-Won;Seo, Young-Jin;Lim, Byung-Jin;Lee, Jun-Bae;Kim, Sang-Don;Heo, Jong-Soo;Cho, Ju-Sik
    • 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.

Estimating CO2 Emission Reduction of Non-capture CO2 Utilization (NCCU) Technology (NCCU(Non-Capture CO2 Utilization) 기술의 CO2 감축 잠재량 산정)

  • Lee, Ji Hyun;Lee, Dong Woog;Gyu, Jang Se;Kwak, No-Sang;Lee, In Young;Jang, Kyung Ryoung;Choi, Jong-shin;Shim, Jae-Goo
    • Korean Chemical Engineering Research
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    • v.53 no.5
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    • pp.590-596
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    • 2015
  • Estimating potential of $CO_2$ emission reduction of non-capture $CO_2$ utilization (NCCU) technology was evaluated. NCCU is sodium bicarbonate production technology through the carbonation reaction of $CO_2$ contained in the flue gas. For the estimating the $CO_2$ emission reduction, process simulation using process simulator (PRO/II) based on a chemical plant which could handle $CO_2$ of 100 tons per day was performed, Also for the estimation of the indirect $CO_2$ reduction, the solvay process which is a conventional technology for the production of sodium carbonate/sodium bicarbonate, was studied. The results of the analysis showed that in case of the solvay process, overall $CO_2$ emission was estimated as 48,862 ton per year based on the energy consumption for the production of $NaHCO_3$ ($7.4GJ/tNaHCO_3$). While for the NCCU technology, the direct $CO_2$ reduction through the $CO_2$ carbonation was estimated as 36,500 ton per year and the indirect $CO_2$ reduction through the lower energy consumption was 46,885 ton per year which lead to 83,385 ton per year in total. From these results, it could be concluded that sodium bicarbonate production technology through the carbonation reaction of $CO_2$ contained in the flue was energy efficient and could be one of the promising technology for the low $CO_2$ emission technology.

Liquid-Composting Conditions of By-product Obtained from Degradation of Animal Carcass for Agriculture Recycling (폐가축사체의 농업적 재활용을 위한 가축사체 액상부산물의 액비화 조건 구명)

  • Seo, Young-Jin;Seo, Dong-Cheol;Kang, Se-Won;Lee, Sang-Gyu;Park, Ju-Wang;Choi, Ik-Won;Sung, Hwan-Hoo;Kang, Seog-Jin;Cho, Ju-Sik
    • Korean Journal of Environmental Agriculture
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    • v.32 no.4
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    • pp.348-354
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    • 2013
  • BACKGROUND: Globally, concern about emerging infectious diseases of livestock is growing. For the disposal of the animal carcass, it is necessary to recycle the carcass into an agriculturally usable product. The objective of this study was to investigate the composting conditions of liquid by-product obtained from degradation of animal carcass. METHODS AND RESULTS: Optimum conditions of liquid fertilizer were investigated using different microorganisms, pHs, and volumes of microorganisms (Lactobacillus rhamnosus+Pichia deserticola). Based on the results from the optimum conditions, compost maturity and quality of liquid fertilizer were evaluated for 112 days. The compost maturity of liquid fertilizer were higher in the order of LP(Lactobacillus rhamnosus + Pichia deserticola) > BC(Bacillus cereus) > BS(Bacillus subtilis). The optimum condition under different volumes of LP was injection of 0.5 mL/100 mL. The compost maturity under different pHs were higher in the order of pH 7 > $$5{\geq_-}9{\frac{._-}{.}}11$$. The liquid by-product at 56 days after composting was completely decomposed. The concentrations of T-N, T-P and $K_2O$ in liquid fertilizer at 56 days were 0.94, 0.17 and 3.78%, respectively, and the sum of those concentrations was 4.89%. CONCLUSION(S): Liquid fertilizer of by-product using pig carcass was decomposed with optimum conditions(LP, pH 7, injection of 0.5 mL/100 mL) in 56 days after composting, and was suitable for official standard of commercial fertilizer.

Investigating the Partial Substitution of Chicken Feather for Wood Fiber in the Production of Wood-based Fiberboard (목질 섬유판 제조에 있어 도계부산물인 닭털의 목섬유 부분적 대체화 탐색)

  • Yang, In;Park, Dae-Hak;Choi, Won-Sil;Oh, Sei Chang;Ahn, Dong-uk;Han, Gyu-Seong;Oh, Seung Won
    • Korean Chemical Engineering Research
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    • v.56 no.4
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    • pp.577-584
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    • 2018
  • This study was conducted to investigate the potential of chicken feather (CF), which is a by-product in poultry industry, as a partial substitute of wood fiber in the production of wood-based fiberboard. Keratin-type protein constituted the majority of CF, and its appearance did not differ from that of wood fiber. When the formaldehyde (HCHO) adsorptivities of CF compared by its pretreatment type, feather meal (FM), which was pretreated CF with high temperature and pressure and then grounded, showed the highest HCHO adsorptivity. In addition, there was no difference between the adsorbed HCHO amounts, which was measured by dinitrophenylhydrazine method, of scissors-chopped CF and CF beated with an electrical blender. Mechanical properties and HCHO emission of medium-density fiberboards (MDF), which were fabricated with wood fiber and 5 wt% CF, beated CF or FM based on the oven-dried weight of wood fiber, were not influenced by the pretreatment type of CF. However, when the values compared with those of MDF made with just wood fiber, thickness swelling and HCHO emission of the MDF were improved greatly with the addition of CF, beated CF or FM. Based on the results, it might be possible to produce MDF with improved dimensional stability and low HCHO emission if CF, beated CF or FM is added partially as a substitute of wood fiber in the manufacturing process of MDF produced with the conventional urea-formaldehyde resin of $E_1$ grade. However, the use of CF or FM in the production of MDF has a low economic feasibility at the current situation due to the securing difficulty and high cost of CF. In order to enhance the economic feasibility, it requires to use CF produced at small to medium-sized chicken meat plants. More importantly, it is considered that the technology developed from this research has a great potential to make provision for the prohibition of animal-based feed and to dispose environmentally avian influenza-infected poultry.

Clinical Characteristics and Prognostic Factors of Severe Community-Acquired Pneumonia (중증 지역사회획득 폐렴의 임상상 및 예후 예측인자에 관한 연구)

  • Oh, Heung-Kook;Seo, Ji-Young;Kim, Dong-Kyu;Choi, Jeong-Eun;Mo, Eun-Kyung;Park, Myung-Jae;Lee, Myung-Goo;Hyun, In-Gyu;Jung, Ki-Suck
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.5
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    • pp.1072-1082
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    • 1997
  • Background : To characterize the clinical features and determine the prognostic factors of severe community-acquired pneumonia. This study is the first of its kind in Korea. Methods : Recruited were 40 patients diagnosed as severe community-acquired pneumonia in Hallym University Hospital from January 1, 1989 through July 31, 1996. Patients were analysed retrospectively for age, sex, underlying disease, respiration rate, hypoxemia, requirement of mechanical ventilation, involvement on chest radiograph, shock, and the serum concentration of BUN and albumin. All parameters were compared between survived and dead group. Results : Male to female ratio was 2.07 : 1. The mean age was $63.1{\pm}17.5$years(range 25~90years) with 65% of patients aged equal to or more than 60. The major underlying diseases were old pulmonary tuberculosis(12.5%), chronic obstructive pulmonary disease(7.5%), bronchial asthma(5%), bronchiectasis(2.5%), and diabetes mellitus(22.5%). Microbiologic diagnosis was made in 26 out of 40 patients(65%). The most common causative organism was S. pneumoniae(17.5%, 7/40) followed by S. aureus(15.0%, 6/40), K. Pneumoniae(12.5%, 5/40), M. tuberculosis(7.5%, 3/40), H. influenzae(2.5%, 1/40), coagulase negative staphylococcus(2.5%, 1/40), P. aeruginosa(2.5%. 1/40), E. cloaceae(2.5%, 1/40), and E. coli(2.5%, 1/40). M. pneumoniae was detected in no patient. The most frequent drugs administered in single or combination therapy were aminoglycosides(75%, 30/40), second- and third-generation cephalosporin(40%, 16/40 and 27.5%, 11/40), macrolides(27.5%, 11/40), and amoxicillin/clavulanic acid(22.5%, 9/40). Of the 40 patients, 14 died of severe community-acquired pneumonia(37.5%). Among them, seven patients (50%) expired within 72h of hospital arrival. According to multivariate analysis, mortality was significantly associated with requirement of mechanical ventilation, bilateral pulmonary involvement, and serum albumins$\leq$3.0g/dl. Conclusion : An understanding of the clinical characteristics and prognostic factors in severe community-acquired pneumonia identified in this study will optimize therapeutic approach in this disease and help decreasing its notorious mortality rate.

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Clinical Characteristics of Chronic Cough in Korea

  • An, Tai Joon;Kim, Jin Woo;Choi, Eun Young;Jang, Seung Hun;Lee, Hwa Young;Kang, Hye Seon;Koo, Hyeon-Kyoung;Lee, Jong Min;Kim, Sung-Kyung;Shin, Jong-Wook;Park, So Young;Rhee, Chin Kook;Moon, Ji-Yong;Kim, Yee Hyung;Lee, Hyun;Kim, Yong Hyun;Kim, Je Hyeong;Lee, Sang Haak;Kim, Deog Kyeom;Yoo, Kwang Ha;Kim, Dong-Gyu;Jung, Ki-Suck;Kim, Hui Jung;Yoon, Hyoung Kyu;Cough Study Group of the Korean Academy of Tuberculosis and Respiratory Diseases
    • Tuberculosis and Respiratory Diseases
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    • v.83 no.1
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    • pp.31-41
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    • 2020
  • Background: Chronic cough is defined as a cough lasting more than 8 weeks and socio-economic burden of chronic cough is enormous. The characteristics of chronic cough in Korea are not well understood. The Korean Academy of Tuberculosis and Respiratory Diseases (KATRD) published guidelines on cough management in 2014. The current study evaluated the clinical characteristics of chronic cough in Korea and the efficacy of the KATRD guidelines. Methods: This was a multi-center, retrospective observational study conducted in Korea. The participants were over 18 years of age. They had coughs lasting more than 8 weeks. Subjects with current pulmonary diseases, smokers, exsmokers with more than 10 pack-years or who quit within the past 1 year, pregnant women, and users of cough-inducing medications were excluded. Evaluation and management of cough followed the KATRD cough-management guidelines. Results: Participants with chronic cough in Korea showed age in the late forties and cough duration of more than 1 year. Upper airway cough syndrome was the most common cause of cough, followed by cough-variant asthma (CVA). Gastro-esophageal reflux diseases and eosinophilic bronchitis were less frequently observed. Following the KATRD cough-management guidelines, 91.2% of the subjects improved after 4 weeks of treatment. Responders were younger, had a longer duration of cough, and an initial impression of CVA. In univariate and multivariate analyses, an initial impression of CVA was the only factor related to better treatment response. Conclusion: The causes of chronic cough in Korea differed from those reported in other countries. The current Korean guidelines proved efficient for treating Korean patients with chronic cough.

Monitoring of Nitrogen and Phosphorus from Submerged Plants in Boknae Reservoir around Juam Lake (주암호 복내 저수구역내 침수 자생식물의 질소 및 인 모니터링)

  • Kang, Se-Won;Seo, Dong-Cheol;Lee, Sang-Gyu;Seo, Young-Jin;Park, Ju-Wang;Choi, Ik-Won;Park, Jong-Hwan;Lim, Byung-Jin;Heo, Jong-Soo;Cho, Ju-Sik
    • Korean Journal of Environmental Agriculture
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    • v.32 no.1
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    • pp.9-16
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    • 2013
  • BACKGROUND: Eutrophication occurs occasionally in reservoirs around lake in summer and early autumn. Lakeside macrophyte which is one of internal pollutants effects on water quality when it is submerged during rainy season. To improve water quality of water supply source in Boknae reservoir around Juam lake, characteristics of nutrient(N, P) uptake and release by submerged plants were investigated. METHODS AND RESULTS: In order to establish the management plan of submerged plants in Boknae reservoir around Juam lake, water level, rainfall, flooding and non-flooding areas, biomass of dominant plants, contents of nitrogen and phosphorus were investigated during 7 months(August, 2010 through February, 2011). Dominant plants were Miscanthus sacchariflorus(MISSA) and Carex dimorpholepis(CRXDM) in Boknae reservoir. Total plant area of Boknae reservoir in August, 2010 was 987,872 $m^2$. In Boknae reservoir, flooding occurred from August until February caused by rainfall during rainy season. The total amounts of nitrogen and phosphorus uptakes by MISSA were 247 and 22 kg/total reservoir area, respectively. By CRXDM, the total amounts of nitrogen and phosphorus uptakes were 11,340 and 1,231 kg/total reservoir area, respectively. The total amounts of nitrogen and phosphorus residues by MISSA were 34 and 11 kg/total reservoir area, respectively. By CRXDM, the total amounts of nitrogen and phosphorus residues were 491 and 68 kg/total reservoir area, respectively. CONCLUSION(S): Total amounts of nitrogen and phosphorus releases in Boknae reservoir were 12,212 and 1,324 kg/total reservoir area, respectively. The results demonstrate that total nitrogen and total phosphorus in water were strongly influenced by submerged plants. Therefore, management plan for submerged plants during rainy season will be needed to improve water quality of water supply source in Boknae reservoir around Juam lake.

Evaluating The Water Resistance of Wood Adhesives Formulated with Chicken Feather Produced from Poultry Industry (도계부산물인 닭털을 이용한 목재접착제의 내수성 평가)

  • Park, Dae-Hak;Yang, In;Choi, Won-Sil;Oh, Sei Chang;Ahn, Dong-uk;Han, Gyu-Seong
    • Journal of the Korean Wood Science and Technology
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    • v.45 no.1
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    • pp.126-138
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    • 2017
  • This study was conducted to investigate the potential of chicken feather (CF), which is a by-product in poultry industry, as a raw material of wood adhesives. For the purpose, adhesive resins were formulated with NaOH- and $H_2SO_4$-hydrolyzed CF as well as crosslinkers, and then the properties and water resistance of the adhesive resins against hot water were measured. CF was made of mainly keratin-type protein, and no or very low content of heavy metals was detected. Hydrolysis rate of CF increased as NaOH concentration in hydrolysis solutions increased. However, in order to minimize the loss of adhesive property of protein itself by the severe hydrolysis of CF and to seek its proper hydrolysis conditions, NaOH concentrations in hydrolysis solution determined to adjust to 5%, 7.5% and 10%. In the NaOH-hydrolyzed CF, $H_2SO_4$-hydrolyzed CF as a hardener and crosslinker were added to formulate CF-based adhesive resins. Solid content of the resins ranged from 28.3% to 44.8% depending on hydrolysis conditions and type of crosslinker. Viscosity of the resins at $25^{\circ}C$ was very high. However, when the temperature of the resins was increased to $50^{\circ}C$, the viscosity decreased greatly and thus the resins could be applied as a sprayable resin. Retention rate measured to evaluate the water resistance of adhesive resins was the highest in the cured resin formulated with 5% NaOH-hydrolyzed CF and 5% $H_2SO_4$-hydrolyzed CF of 10% based on the solid weight as a hardener. Retention rate depending on crosslinkers added into adhesive resins was the highest phenol-formaldehyde (PF) followed by melamine-urea-formaldehyde (MUF) and formalin. The retention rate of CF-based adhesives formulated with 5% NaOH-hydrolyzed CF, PF and $H_2SO_4$-hydrolyzed CF of 10% and over did not differ statistically from that of commercial MUF resins. All of CF-based adhesives formulated with PF as a crosslinker and one with 5% NaOH-hydrolyzed CF of 55%, 5% $H_2SO_4$-hydrolyzed CF of 15%, and MUF of 30% on the basis of solid weight could be substituted for commercial urea-formaldehyde resins, From the results, CF can be used as a raw material of wood adhesives if hydrolyzed in proper conditions.

Evaluation of Treatment Efficencies of Pollutants in Juksancheon Constructed Wetlands for Treating Non-point Source Pollution (비점오염원 저감을 위한 죽산천 인공습지의 오염물질 정화효율 평가)

  • Choi, Ik-Won;Seo, Dong-Cheol;Kang, Se-Won;Lee, Sang-Gyu;Seo, Young-Jin;Lim, Byung-Jin;Park, Jong-Hwan;Kim, Kap-Soon;Heo, Jong-Soo;Cho, Ju-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.4
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    • pp.642-648
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    • 2012
  • To evaluate the water quality in Juksancheon constructed wetlands for treating non-point source pollution, the removal rates of nutrients in water and the total amounts of T-N and T-P uptakes by water plants were investigated. Chemical characteristics of T-N and T-P in sediment were investigated. The concentrations of BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand), SS (Suspended Solids), T-N and T-P in inflow were 0.07~1.47, 0.60~2.65, 0.50~4.60, 1.38~6.26 and $0.08{\sim}0.32mg\;L^{-1}$, respectively. The removal rates of BOD, COD, SS, T-N, and T-P were -10, 51, 66, -3 and 5%, respectively. The maximum amount of T-N uptake by water plants in August was $368.7mg\;plant^{-1}$ in the $2^{nd}$ treatment stage by Nymphoides peltata, $1314.6mg\;plant^{-1}$ in the $3^{rd}$ treatment stage by Iris pseudacorus, $1160.4mg\;plant^{-1}$ in the $4^{th}$ treatment stage by Nymphaea tetragona GEORGI, respectively. The maximum amount of T-P uptake by water plants in August was $121.7mg\;plant^{-1}$ by Nymphoides peltata in the $2^{nd}$ treatment stage, $268.7mg\;plant^{-1}$ by Iris pseudacorus in the $3^{rd}$ treatment stage and $212.0mg\;plant^{-1}$ by Nymphaea tetragona GEORGI in the $4^{th}$ treatment stage, respectively. Organic matter contents in sediments were not different. Contents of T-N and T-P in sediments were higher in spring. Microbial biomass C:N:P ratios in sediments in spring, summer, autumn and winter were 117~140:1~4:1, 86~126:5~6:1, 68~101:2~6:1 and 47~138:2~4:1, respectively. We could conclude that Juksancheon constructed wetlands show high removal efficiencies of COD and SS. However, improvements of management in winter season should be considered to improve the removal efficiencies of pollutants.