• Journal of Applied Biological Chemistry
• /
• v.53 no.4
• /
• pp.232-238
• /
• 2010

In order to investigate the treatment efficiency of pollutants in free water surface constructed wetlands (FWS CWs) with lotus (Nelumbo nucifera) cultivation pond, the experiment was consisted of two sites (site I and II) in Lake Juam, Korea. The sites were configured a lotus cultivation pond (with fertilizer application) - a dropwort bed - a reed bed for site I, and a lotus cultivation pond (without fertilizer application) - a dropwort bed - a reed bed for site II. Removal rate of COD in site I and II were 13.3% and 26.0%, respectively. Removal rate of total nitrogen (TN) was 29.7% for site I, and 36.3% for site II. Removal rate of total phosphorus (TP) in site I and II were 36.0% and 36.5%, respectively. COD, TN and TP in effluent from site I (with fertilizer) was higher than that in site II (without fertilizer), showing that COD, TN and TP in effluent were strongly influenced by fertilizer addition. Therefore, in order to satisfy established water-quality standards, the amount of fertilizer used in lotus cultivation showed be evaluated.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.14 no.1
• /
• pp.11-22
• /
• 2011

This study was established to build and suggest the Ecological Performance Standards for replaced wetlands as the mitigation strategies for the construction projects. The request performance and assessment factors and standards were derived by bibliographic review and verified by the field survey for the reference wetlands. And the weights for each factor were derived by AHP(Analytical Hierarchy Process) method. The results are as follows : 1) Assessment factors were induced by in-depth research of many wetland assessment models and benchmarks evaluated ecological functions. This study proposed final 12 assessment factors through ecological specialist and experts interviews added with literature analysis. 2) 10 natural wetlands were selected as Reference Wetlands as the measure to propose assessment factors and assessment criteria. Those reference wetlands are well-conserved inland natural wetlands classified to the one having worthy to conserve (grade "high") according to RAM(Rapid Assessment Method). Reference wetlands chosen by the study are Parksilji, Jeongyangji, Mulkubi, Bawineupkubi, Jilnalneup, Jinchonneup, Doomoso, Haepyung wetland, Whangjeong wetland, and Whapo wetland. The research developed assessment criteria for the performance assessment factors based on several explorations of the reference wetlands. 3) "Requiring performance" of replaced wetlands is defined as "to carry out similar or same ecological functions provided by natural wetlands", in overall. The detailed requiring performances are as follows; ${\bullet}$ to play a role of wildlife habitats ${\bullet}$ to have biological diversity ${\bullet}$ to connect with other ecosystems ${\bullet}$ to provide water environment to perform good ecological functions 4) The assessment factors for required performance are categorized by wildlife habitat function, biological diversity, connectivity of adjacent ecosystem, and water environment. Wildlife habitat category is consisted of wildlife habitat creation, size of replacement wetland, and site suitability. Biological diversity category contains the number of plant species, the number of wildlife species, and number of protected species as the sub-factors. Connectivity of adjacent ecosystem is comprised of wildlife corridor, green network and distance from other ecosystem. Finally, water environment make up with water quality, depth of water body, and shape of waterfront. 5) Finally, every assessment factors were verified and weighted by the AHP methods and the final standards were proposed. The weights of factors of requiring performance suggested as habitat (0.280), connectivity (0.261), diversity (0.260), hydraulic environment (0.199). And those of detailed sub-factors are site suitability (0.118), protected species (0.096), distance to neighbor ecosystem (0.093), habitat creating (0.091), green corridor (0.090) etc.

• Journal of Wetlands Research
• /
• v.10 no.2
• /
• pp.39-51
• /
• 2008

In recent days, the cases of using wetlands in treating waste water, storm events, mining leachate, and agriculture effluents are increasing. But there is the lack of the data for wetlands because of the difficulty in long term monitoring. Such an aspect makes the proper use of wetland impractical. In this study for the purpose of generating a long term hydrologic data, the time series of storage amount for Upo, Mokpo, Sajipo, and Jjokjibeol in Topyeong watershed is simulated using SWAT model. Based on the SWAT-Topyeong model involved in several scenarios for constructing new washlands in Topyeong watershed, the temporal behavior of new washlands is analyzed. It is also revealed that the constructed washland can affect the Upo in some degrees.

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

• Korean Journal of Environmental Agriculture
• /
• v.22 no.4
• /
• pp.266-272
• /
• 2003

This study was conducted to evaluate effects of 2 constructed wetlands with different vegetation states (plumpton park wetland and Woodcroft park wetland) for reducing non-point source pollution from small watershed consisted of residential and agricultural area in suburban district of Sydney, Australia. The total nitrogen and phosphate removal efficiency of Plumpton park constructed wetland, composed of stable and dense vegetation, were 38.3% and 26.2% and Woodcroft park constructed wetland having still poor vegetation due to the short time to settle down transplanted plants after construction, showed relatively low removal efficiency of 20.2% and 14.0%. The removal efficiency of inorganic nutrients such as $NH_4-N$, $NO_3-N$, $PO_4^{-3}$ were higher than total nitrogen and phosphate because plants and microorganisms in rhizosphere of constructed wetlands took up inorganic nutrients shortly. According to the type of wetland inflow, the nutrients removal efficiency of storm water flow was lower than base flow.

• Journal of Environmental Impact Assessment
• /
• v.32 no.5
• /
• pp.291-304
• /
• 2023

Harmful algal blooms (HABs) have become an increasing concern in terms of human health risks as well as aesthetic impairment due to their toxicity. The reduction of water pollutants, especially nutrients from non-point sources in a reservoir watershed, is fundamental for HABs prevention. We investigated the pollutant removal efficiencies of a constructed wetland to evaluate its feasibility as a method for controlling non-point sources located in the Annaecheon stream within the Daecheong Reservoir watershed. The overall removal efficiencies of pollutants were as follows: BOD 14.3%, COD 17.9%, SS 50.0%, T-N 19.0%, and T-P 35.4%. These results indicate that constructed wetlands are effective in controlling pollutants from non-point sources. The seasonal variation in removal efficiency depended on the specific pollutants. The removal efficiencies of BOD, COD, and T-N were stable throughout the year, except during winter, which might have been influenced by lower microorganism activity. In contrast, T-P showed a consistent removal efficiency even during the winter season, suggesting that the wetland can reduce external phosphorus loading to the reservoir. Regarding the effects of pollutant loadings on removal efficiency, the effluent concentrations of all pollutants were significantly decreased compared to those in the influent in case of middle and high loadings. This demonstrates that constructed wetlands can handle high pollutant loads, including the initial runoff during rainfall, to prevent reservoir eutrophication. Despite the various strengths of wetland water purification, there are limitations as passive treatment. Therefore, more case studies should be conducted to suggest optimum operational conditions for constructed wetlands, taking into consideration reservoir-specific characteristics.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.2
• /
• pp.263-270
• /
• 2011

Boknae Bio-park is a free water surface constructed wetlands to remove non-point source pollution. Boknae Bio-park constructed wetlands (CWs) consist of forebay, wetlands ($1^{st}$, $2^{nd}$, and $3^{rd}$ wetlands), and micropool. The concentrations of BOD, SS, T-N and T-P in inflow were 1.87-4.23, 5.2-24.0, 4.94-15.59 and $0.10-0.75mg\;L^{-1}$ in Boknae Bio-park CWs from April to December in 2008, respectively. The removal rates of BOD, SS, T-N and T-P in Boknae Bio-park CWs were 26, 43, 62 and 83%, respectively. The removal rates of BOD and SS in the spring and summer were higher than those in other seasons. The removal rates of T-N and T-P on spring were slightly higher than those in other seasons. The amounts of pollutants removal in Boknae Bio-park CWs were higher in the order of forebay > wetlands > micropool for BOD, wetlands > forebay > micropool for SS and wetlands > forebay > micropool for T-N. The amount of T-P removal was not significant different in all areas.

• Journal of Wetlands Research
• /
• v.14 no.1
• /
• pp.121-130
• /
• 2012

This study is to investigate the removal rates of nutrient in water, the biomass of water plants, and the total amounts of T-N and T-P uptakes by water plants to evaluate the ecological characteristics of the constructed wetland for treatment of livestock wastewater in Yangji-ri, Nonsan-si from June through November 2011. During the experimental period, the monthly plant biomass of constructed wetland in July were the highest as 669.4 kg, while the lowest in November as 200.1 kg. The research showed that the average nitrogen and phosphorus contents in aboveground and underground biomass of Phragmites australis were $21.9{\pm}0.6{\sim}32.1{\pm}1.5mg/g$, $15.1{\pm}5.5{\sim}24.9{\pm}5.7mg/g$, $1.5{\pm}0.3{\sim}2.4{\pm}0.2mg/g$ and $1.6{\pm}0.6{\sim}2.5{\pm}0.6mg/g$, respectively. The maximum amount of T-N and T-P uptake by Phragmites australis were 28.0 kg in July and 2.5 kg in June, respectively, while the minimum amount of T-N and T-P uptake by Phragmites australis were 9.7 kg and 0.7 kg in November, respectively. The removal rates of T-N and T-P in constructed wetland for treating livestock wastewater were 23.0 % and 59.1 %, respectively. The results of this study is expected to deduce the circulation of contaminants and nutrient in the wetland afterwards.

• Journal of Wetlands Research
• /
• v.19 no.1
• /
• pp.80-89
• /
• 2017

Researches about NPS(Non-point Pollution Source) reduction have been widely carried out in recent years. A pilot channel-type constructed wetland (wet swale) was constructed in Rongyin area to treat stormwater generated from a green house agro-land of 22.7 ha. From 2006 to 2008, monitoring was conducted to evaluate its performance on the removal effect for organic pollutants as well as nutrients. Totally, sampling trips of 17 rainfall events were made and they covered most types of storm events in Korea. The channel-type constructed wetland have average removal efficiencies of 78.3~92.0%, 56.4~66.1%, 28.2~45.5% and 50.6~66.4% for SS, COD, TN and TP, respectively. According to four methods for estimating the removal efficiency, the average efficiencies of TSS, COD, TN and TP are 86.0%, 60.1%, 30.1% and 53.5%, respectively. From 2006 to 2008, annual efficiency improved due to infiltration potential increase. It was found that most of the pollutants removed in this channel type of wetland was particulate solids bound pollutants, which is assumed fact that it lacks of physico-chemical treatment conditions which are commonly observed in the retention type of constructed wetlands.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2004.11a
• /
• pp.121-121
• /
• 2004