• Journal of Wetlands Research
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• v.17 no.4
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• pp.428-435
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• 2015

Constructed wetlands (CWs) have been accepted as an attractive and economic alternative to a variety of pollution control and provided potentially valuable wildlife habitat in urban and suburban areas, as well as esthetic value within the local natural environment. CWs are known eco-friendly technology to solve the problem of the climate change and urbanization issues. Numerous studies have been published on the various aspects of a CW. However, there are current limitations about the CW operations such as few design guidelines, poor performance results regarding the simple construction. Therefore, the objective of this research was to suggest an appropriate design and maintenance guidelines for a CW by thorough investigation of site monitoring results. The research also concentrated in redefining and reclassifying CWs, based on literatures made by the Ministry of Environment (MOE) and other organizations. Investigation at 43 CWs in Korea was performed by using collected data and by performing site survey from 2013 to 2014. Based on the results, the best practices among the investigated CWs provided water treatment, wildlife habitat, environmental education, and leisure. Also these CWs conducted a regular maintenance such as vegetation, sediment dredging and cleaning of facilities. Results obtained are intended for use by academics and any organizations involved in CW management.

• Korean Journal of Ecology and Environment
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• v.40 no.1
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• pp.61-71
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• 2007

The photosynthetic characteristics and primary production by phytoplankton in open waters of two wetlands (the Banwol and the Donghwa wetland) of Sihwa Constructed Wetland with different water chemistry were investigated to provide the information for the wetland management considering the water treatment efficiency. During the study period (from March to October, 2005) the primary productivity in open waters ranged from 481 to 11,275 mgC $m^{-2}$ $day^{-1}$, which is very high compared with the eutrophic level of 600mgC $m^{-2}$ $day^{-1}$. From the analysis of the photosynthesis-irradiance (P-I) model parameters, the photosynthetic characteristics may be affected by different concentration and ratio of nutrient (N and P) between two wetlands. Assimilation number (AN) was higher in the Donghwa wetland (average AN: 8.5gC $gChl^{-1}$ $hr^{-1}$) with high P and low N/P ratio than the Banwol wetland (average AN: 5.8gC $gChl^{-1}$ $hr^{-1}$) with high N and high N/P ratio. This result indicates that AN may be concerned with phosphorus than nitrogen and low NIP ratio. Positive correlation (R=0.81) was observed between the initial slope and AN, implying that AN was high in case of phytoplankton having more active photosynthesis ability under low light. On the other hand, maximum photosynthesis (Pmax) was related positively with chlorophyll a concentration showing correlation coefficient of 0.47. In this study, considering the high primary production through phytoplankton photosynthesis in open waters of Sihwa Constructed Wetland, the produced organic matter by phytoplankton may affect the water quality within wetland and its efficiency of water treatment. Also, the photosynthetic characteristics may be affected by different nutrient enrichment (especially phosphorus) of wetlands. This study suggests that the production by phytoplankton and its characteristics in open water of constructed wetland for water treatment should be considered to improve the removal efficiency of organic matter.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.6
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• pp.30-36
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• 2002

A 0.19 hectare natural-type wetland for stream water treatment demonstration was constructed and planted with cattails from April 2001 to May 2001. Part of its bottom surfaces adjacent to levees have a variety of slope of 1 : 4~1 : 15. Two small open water areas were installed, in which emergent plants could not grow. Removal of nutrients from stream waters was a major objective of the wetland. Waters of Sinyang Stream flowing into Kohung Estuarine Lake were pumped and funneled into the wetland. The lake had been formed by a salt marsh reclamation project and was located southern coastal region of Korean Peninsula. Volumes and water quality of inflow and outflow were analyzed from July 2001 through December 2001. Inflow and outflow averaged $120.4m^3/day$ and $112.1m^3/day$, respectively. Hydraulic retention time was about 3.1 days. Average total phosphorous concentration of influent and effluent was $0.19mg/{\ell}$ and $0.075mg/{\ell}$, respectively. Total phosphorous loading rate of inflow and outflow averaged $12.05mg\;m^{-2}\;day^{-1}$ and $4.44mg\;m^{-2}\;day^{-1}$, respectively. Average total phosphorous removal rate in the wetland was $7.61mg\;m^{-2}\;day^{-1}$. Seasonal changes of phosphorous retention rates were observed. The wetland acted as effective phosphorous sinks in the initial stage of the constructed wetland.

• 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.

• Korean Journal of Environmental Agriculture
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• v.31 no.4
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• pp.344-350
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• 2012

BACKGROUND: To design and develop a constructed wetland for effective livestock wastewater treatment, it is necessary to understand the removal mechanisms of various types of pollutants in constructed wetlands. The objective of this study was to evaluate the treatment efficiency of pollutants under different types of fraction in constructed wetland system for treating piggery wastewater. METHODS AND RESULTS: The piggery wastewater treatment plant that consisted of activated sludge tank, aerobic and anaerobic beds was constructed. The concentration of COD(Chemical oxygen demand) in effluent by fraction was 71.5 mg/L for soluble COD, 142 mg/L insoluble COD. The concentration of SS(Suspended solid) in effluent by existing form was 102 mg/L for volatile SS, 15.5 mg/L for fixed SS. The concentration of T-N(Total nitrogen) and T-P(Total phosphorus) in effluent by existing form were 12.8 mg/L and 3.05 mg/L for dissolved form, 35.0 mg/L and 1.93 mg/L for suspended form. The removal efficiencies of COD, SS, T-N and T-P in hot season(summer and autumn) were higher than those in cold season(spring and winter). The removal efficiencies of COD, SS, T-N and T-P in effluent were 98.0, 99.0, 98.2 and 99.2% for all seasons, respectively. CONCLUSION(S): The results indicated that removal types of pollutants were insoluble COD(ICOD), volatile SS(VSS), dissolved T-N(DTN) and dissolved T-P(DTP) in constructed wetlands for treating piggery wastewater.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.4
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• pp.64-71
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• 2001

Treatment efficiency was examined of a pond-wetland system constructed for water quality conservation of Koheung Estuarine Lake over one year after its establishment in July 2000. The system is composed of primary and secondary ponds in series and six wetland cells in parallel. Cattails (Typha angustiflora) were planted in three wetland cells and common reeds (Phragmites australis) in three other cells. Water pumped from Sinyang Stream flowing into the Lake was funneled into primary pond whose effluent was discharged into secondary pond by gravity flow. Effluent from secondary pond was distributed into each wetland cell. SS, $BOD_5$, T-N, and T-P concentrations in influent to primary pond, and effluent from primary pond, secondary pond, and three wetland cells planted with cattails were analyzed for about one year from August 2000 to August 2001. The removal rates at primary pond for SS, $BOD_5$, T-N and T-P were 29%, 30%, 15%, and 36%, respectively. The abatement rates at secondary pond for SS, $BOD_5$, T-N and T-P were 38%, 40%, 30%, and 47%, respectively. The reduction rates measured at three cattail-planted wetland cells for SS, $BOD_5$, T-N and T-P were 54%, 57%, 60%, and 68%, respectively. Considering early stage of the pond-wetland system and inclusion of winter during the research period, its treatment efficiency was rather good. Cattails had not yet grown to dense stands due to initial establishment period, which resulted in slightly lower treatment efficiencies of wetland cells for these pollutants, compared with those of ponds.

• Journal of Wetlands Research
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• v.19 no.3
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• pp.296-302
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• 2017

Generally, a parking lot is constructed using asphalt or concrete. Such materials are impermeable, which means that a parking lot will directly release pollutants to any nearby water system during a rainfall event. An increased quantity of nonpoint source pollutants harms the ecohydrological system and causes further environmental damage leading to dysfunctional water circulation systems. Therefore, there is an urgent need for the design and application of Low Impact Development (LID) systems that allow more effective prevention of water circulation problems and management of nonpoint source pollution. This study aims to support such efforts by analyzing a permeable paver parking lot constructed using one of the LID techniques and comparing it to a conventional one in terms of the concentration of pollutants, nonpoint source pollution load and runoff rainfall lag effects during a rainfall event; it could serve as a reference for the construction of permeable paver parking lots in the future.

• Korean Journal of Ecology and Environment
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• v.48 no.3
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• pp.188-194
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• 2015

River channel dredging and riparian development have been influenced morphology and quantity of natural river habitat. We compared distribution of riverside land and alluvial island in the Nakdong River with field survey and remote sensing analysis after the 4 Large River Project in South Korea. We digitized geomorphological elements, includes main channel, riverside land, and alluvial island by using georeferenced aerial photos taken in pre-dredging (2008) and post-dredging (2012) periods. Field survey was followed in 2012 for a ground truth of digitized boundaries and identification of newly constructed wetland types such as pond, channel, branch, and riverine type. We found that during the dredging period, riverside land and alluvial island were lost by 20.2% and 72.7%, respectively. Modification rate of riverside land was higher in the section of river kilometer 50~90, 140~180, and 210~270. Alluvial island had higher change rate in the section of river kilometer 50~70, 190~210, and 270~310. Average change rate for the riverside land and alluvial island was $-1.02{\pm}0.14km^2{\cdot}10km^{-1}$ and $-0.05{\pm}0.05km^2{\cdot}10km^{-1}$, respectively. Channel shaped wetlands (72.5%) constituted large portion of newly constructed wetlands.

• Journal of Wetlands Research
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• v.24 no.3
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• pp.161-169
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• 2022

In this study to estimate suitable size of rain tank in Suwon district, monthly rainfall, daily rainfall duration curve and daily rainy days have been analyzed. Annual rainwater consumption and daily average amount of storage with respect to size of rain tank have been calculated by applying continuity equations that take account of daily rainfall, daily consumptive use, storage of rain tank, It has been shown that above 50 mm of rainfall in the ordinance related to reclamation water may be inappropriate regulation if annual amount of rainfall captured, efficiency of utilized rainwater, number of days for utilized rain tank, daily average amount of storage and daily consumptive use have been considered. Thus, it has been shown that suitable size of rain tank should be determined considering reasonable daily consumptive use with respect to district, constructed cost of rain tank and benefit of rain tank constructed.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.304-309
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• 2011

BACKGROUND: Generally, water plants may play an important role in nutrients(N, P) removal in constructed wetlands(CWs). Previous studies considered nutrients uptake by water plants in various CWs for treating point source pollution. On the other hand, few studies considered nutrients uptake by water plants in free water surface(FWS) CWs for treating non-point source pollution. METHODS AND RESULTS: To investigate characteristics of nutrient uptake by water plants in FWS CWs, dry weights, nutrients content and nutrients uptake by water plants were investigated from April, 2008 to October, 2008. Dominance plants were Phragmites japonica STEUD (PHRJA), Nymphaea tetragona ANGUSTA(NTMTE), Typha orientalis PRESL(TYHOR), Phragmites communis TRINIUS(PHRCO) and Zizanis latifolia TURCZ(ZIZLA) in FWS CWs. The dry weights of water plants in August were higher in the order of TYHOR(54.27 g/plant) > PHRJA(44.30 g/plant) ${\geqq}$ PHRCO(39.60 g/plant) ${\geqq}$ ZIZLA(37.80 g/plant) ${\fallingdotseq}$ NTMTE(36.75 g/plant). The T-N and T-P contents by water plants were not significantly differences regardless of cultivation period. The maximum amount of T-N uptake by water plants in August were 773 mg/plant for PHRJA, 625 mg/plant for NTMTE, 1206 mg/plant for TYHOR, 754 mg/plant for PHRCO and 768 mg/plant for ZIZLA. The maximum amounts of T-P uptake by PHRJA, NTMTE, TYHOR, PHRCO and ZIZLA were 397, 177, 411, 261 and 229 mg/plant in August, respectively. CONCLUSION(s): The results of this study suggest that optimum water plant was Typha orientalis PRESL in free water surface constructed wetlands.