• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.05a
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• pp.22-22
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• 2004

• Korean Journal of Ecology and Environment
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• v.38 no.3 s.113
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• pp.403-411
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• 2005

The Shihwa constructed wetland was established for the treatment of severely polluted water from Banwoul, Donghwa and Samhwa streams, This study was focused on investigating dynamics of phytoplankton community at 5 stations of open waters in the Shihwa constructed wetland from October 2001 to July 2002. The concentration of T-N and T-P of inlet stations from the streams were decreased by flowed through the wetland. However, the TN/TP ratios at all stations were shown as a little over 16 indicating that the T-P plays an important role as a limitation factor. Phytoplankton communities were identified as a total of 413 taxa which were composed of 375 species, 21 varieties, 2 forma and 15 unidentified species. The standing crops of phytoplankton communities and chlorophyll-a concentrations ranged 330 ${\sim}$ 36, 420 cells $mL^{-1}$ and $2.5\;{\sim}\;170.7\;{\mu}g\;L^{-1}$ respectively, and showed a decreasing tendency after flowing through the wetland at almost stations. Dominant species were 14 taxa at all stations which were Euglena oblonga, Synura spinosa, and etc. The species composition, standing crops and chlorophyll concentrations of phytoplankton communities appeared a distinct differences between open waters of inlet from stream and open waters flowed through the wetland. Theses results were affected from decreasing effects of TN, TP and SS by flowed through the wetland from inlet waters of streams.

• Journal of Wetlands Research
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• v.15 no.3
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• pp.397-406
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• 2013

Wetland conservation plan has been established to protect ecologically important wetlands based on vegetation integrity, spatial distribution of endangered species, but recently more demands are concentrated on the landscape ecological approaches such as topological relationship, neighboring area, spatial arrangements between wetlands at the broad scale. Landscape ecological analysis and graph theory are conducted to identify spatial characteristics related to core nodes and weak links of wetland networks in Nakdong basin. Regular planar model, which is selected for wetland networks, is applied in the Nakdong basin. The analysis indicates that 5 regional groups and 4 core wetlands are extracted with 15km threshold distance. The IIC and PC values based on the binary and probability models suggest that the wetland group C composed of main stream of Nakdong river and Geumho river is the most important area for wetland network. Wetland conservation plan, restoration projected of damaged and weak links between wetlands should be proposed through evaluating the node, links, and networks from wetlands at the local to the regional scale in Nakdong basin.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.41-48
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• 2003

Nitrogen removal rate and emergent plant growth were investigated of a free-water-surface constructed treatment wetland system, whose dimensions were 31m in length and 12m in width. The system was constructed on floodplain in the Kwangju Stream from May to June 2001. Cattails(Typha angustifolia) were transplanted from natural wetlands and their stems were cut at about 40cm height from their bottom ends. Water of the Kwangju Stream were funneled into the system by gravity flow and its treated effluent was discharged back into the stream. The average height of the cattail stems was 45.2cm in July 2001 and 186cm in October 2001. The number of stems averaged 22 stems/$m^2$ in July 2001 and 52 stems/$m^2$ in September 2001. Volume and water quality of inflow and outflow were analyzed from July 2001 through December 2001. Inflow and outflow averaged 40.01 and 39.55 $m^3$/day, respectively. Hydraulic detention time was about 1.5 days. Average nitrogen uptake by cattails was 69.31 $N\;mg\;m^{-2}\;day^{-1}$. Removal rate of $NO_3-N$, $NH_3-N$ and T-N averaged 195.58, 53.65 and 628.44 $mg\;m^{-2}\;day^{-1}$, respectively. The average removal rate of T-N was about 39%.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.4
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• pp.11-23
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• 2018

The purpose of this study is to identify the ecological characteristics and biological interactions between species of the abandoned rice paddy field in mountainous areas and to suggest a management strategy for stable food chain formation and biodiversity enhancement. The study site is located in Uldae wetland of Songchu district Bukhansan National Park, site characteristics and biological habitat characteristics were identified through site survey and literature survey. With regard to physical environment, among geographical features, the Uldae Wetland and the neighborhood inside the basin was a gently sloping area($5{\sim}15^{\circ}$). And 64.0% of basin faced the north. With regard to water environment, the Uldae Wetland was wetland of rainfed paddy field depending on precipitation and the system of stream flowing into the wetland from valley. According to the results of examining flora in plant ecology, in general, they were herbaceous wetland species. 88.6% of existing plants inside the Uldae Wetland basin was a forest in the mountain. And Quercus spp. community and Pinus densiflora community accounted for 64.6% of that, and was dominant. Except for that, Salix koreensis community was distributed. The existing vegetation of Uldae Wetland inhabited wetland species and terrestrialization indicator species, and it was thought that partial terrestrialization inside the Uldae Wetland was in progress after the discontinuation of paddy cultivation, such as the expansion of Salix koreensis distribution area. In the status of appearing faunae in the Uldae Wetland with regard to wildbirds of appearing principal species, The Uldae wetland was based on a abandoned rice paddy field various wildlife, and was a wildlife feeding, spawning, and resting place. The water environment was an important factor in maintaining the wetland living creatures function, habitat of waterbirds and benthic macroinvertebrates, amphibians and odonate are spawning ground and habitat, it was affecting the vegetation ecosystem based on wetlands. In order to maintain the diversity of wildlife, it was important to maintain smooth water supply and water level. A stable food chain will be formed and the Uldae wetland biodiversity will be abundant by establishing the relationship between the species of Uldae wetland, which is abandoned rice paddy field, and the habitat environment favored by species belonging to the ecosystem stepwise linkage. The ecological characteristics of the Uldae wetlands and the relation between the species were analyzed and the environmental conditions were reflected in the planning and management plan of Uldae wetland ecology.

• Journal of Environmental Science International
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• v.26 no.3
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• pp.401-410
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• 2017

This study analyzed the changes in the concentrations of organic matters in constructed treatment wetlands, coming from discharge water from a sewage treatment plant and non-point pollutant sources during rainfall events. At the beginning of a rainfall event, a massive amount of particulate organic matter flowed in, and was removed from the sedimentation basin (S1, S2); dissolved organic matter was removed after passing through stepwise treatment processes in the wetland. During dry period in the wetland, the removal efficiency rate for COD and TOC was -21 and -7%, respectively; during the rainfall event, the removal efficiency rate for COD and TOC were 47 and 43%, respectively. The highly-concentrated organic matters that flowd in at the beginning of the rainfall event was stabilized by various structures in the wetland before water discharge. Cyanobacteria blooms annually at the confluence of the So-ok stream and Daecheong Lake. Therefore, it is expected that the wetland will contribute significantly to reducing cyanobacteria and improving water quality in the area.

• Journal of Environmental Impact Assessment
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• v.23 no.1
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• pp.67-74
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• 2014

The aim of this study was evaluated the effects of total rainfall, rainfall intensity and antecedent dry days and identify the correlation analysis with the EMC removal efficiency, in order to provide an understanding of the operation and maintenance factors of constructed wetland in flood pumping station. This study was conducted total of 20 monitoring in a catchment(326.2 ha) of constructed wetland in Ga-un flood pumping station located at the downstream of the Wang-suk stream. The determined EMC removal efficiencies were $36.04{\pm}9.45%$ for BOD, $38.50{\pm}13.50%$ for $COD_{Mn}$, $34.34{\pm}13.05%$ for TN and $34.22{\pm}14.27%$ for TP, respectively. These results showed that the pollutants concentration and EMC were reduced while passing through the constructed wetland. In the correlation analysis, the highly correlations with EMC removal efficiency of BOD and $COD_{Mn}$ were observed for total rainfall and rainfall intensity (P<0.05). However, the correlations were not found with TN and TP for rainfall variables.

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.91-102
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• 2010

Water quality and epiphytic diatom on the submerged stems of reed (Phragmites communis), which occupy 90% of the Donghwa wetland macrophytes were monthly monitored at three points such as inflow stream, high- and low-level wetlands, and outflow stream between March and October, 2005. 1) A diverse and high density of diatom species observed in the cold-season, especially Nitzschia palea and Nitzschia amphibia dominated the diatom community without wetlands. 2) High DAIpo and TDI indices were measured over the sampling periods and stations, regardless of nitrogen increase and phosphorus increase through the wetlands. 3) Higher density of diatom species in high wetland than low wetlands was attributed in the enough nutrients and light penetration by low growth of reed. Therefore, epiphytic diatom of reed stem in Donghwa wetland, where high nutrients released from the sediment and reed debris after the death of macrophytes, flourished with low canopy of low reed vegetation.

• Clean Technology
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• v.25 no.4
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• pp.302-310
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• 2019

A constructed wetland with the aerobic tank and anaerobic/anoxic tank connected in series was employed in order to treat highly polluted stream water. The aerobic tank was maintained aerobic with a continuous supply of air through the natural air draft system. Five pilot plants having different residence times were employed together to obtain parameters for the best performances of the wetland. BOD and COD removals at the aerobic tank followed the first order kinetics. COD removal rate constants were slightly lower than BOD. The temperature dependence of COD (θ = 1.0079) and BOD (θ = 1.0083) was almost the same, but the temperature dependence (θ_N) of T-N removal was 1.0189. The SS removal rate was as high as 98% and the removal efficiency showed a tendency to increase with increasing hydraulic loading rate (Q/A). The main mechanism of BOD and COD removal at the anaerobic/anoxic tank was entirely different from that of the aerobic tank. BOD and COD were supplied as the carbon source for biological denitrification. T-P was believed to be removed though the cation exchange between orthophosphate and gravels within the anaerobic and anoxic tanks. The wetland could successfully be operated without being blocked by the filtered solid which subsequently decomposed at an extremely fast rate.

• Korean Journal of Environmental Agriculture
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• v.21 no.4
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• pp.269-273
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• 2002

A 0.19 hectare stream water purification demonstration wetland was constructed and planted with cattails from April 2001 to May 2001. Some portions of its bottom surfaces adjacent to levees have a variety of slope of 1:4 $\sim$ 1:15 and two small open water areas were installed in the wetland. These make its shape closer to a natural wetlant Nitrogen removal was a major objective of the wetlant Waters of Sinyang Stream flowing into Kohung Esturiane Lake located southern coastal region of Korean Peninsula were pumped and funneled into it. Volumes and water quality of inflow and outflow were analyzed from July 2001 through December 2001. Average inflow and outflow were 120 $m^3/d$ and 112 $m^3/d$, respectively. Hydraulic retention time was about 3.1 days. Average nitrate and total nitrogen removal rate for the early stage of the wetlands were 85.8 $mg/m^2/day$, 171.4 $mg/m^2/day$ respectively. Full establishment of cattails within a few years can develope litter-soil substrates and supply available carbon sources beneficial to the denitrification of nitrate. These can lead to increases of the nitrate retention rate. Short circuiting and dead zone areas which might be occurred due to the close-to-nature layout of the wetland were not observed during the monitoring period.