• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.2-2
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• 2018

• Journal of Wetlands Research
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• v.17 no.1
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• pp.53-61
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• 2015

Habitat creation for endangered species Menyanthes trifoliata L. using planting module represents a habitat type such as the rhizome grows horizontally to open water at the margin of the lake. The objectives of this mesocosm experiment are habitat creation with easy construction and low management effort, and to investigate the potential of providing a habitat for aquatic macroinvertebrates. Planting modules had three different substrates of bed soil, perlite and K-SOIL (artificial lightweight soil using bottom ash). These modules were established in two different size of the tub($1170{\times}2250{\times}300mm^3$, $900{\times}1360{\times}190mm^3$). According to the monitoring results, number of leaves and coverage of M. trifoliata showed significant difference with substrate and tub size. The number of leaves showed similar growth responses in bed soil (mean 22.979) and K-SOIL (mean 28.042) substrates but growth was poor in perlite substrate (mean 1.667). The number of leaves in the large tub was more than small tub (p=0.015). Similar responses were obtained with the coverage, the length of rhizome and the number of rhizome in M. trifoliata. A total of 21 taxa of aquatic macroinvertebrates including 1,145 individuals was found in the mesocosm. The Shannon diversity index and colonization index in the mesocosm were similar to the previous studies. These results suggest that the experimental mesocosm could provide sufficient habitats for aquatic macroinvertebrates. If planting modules use bed soil or K-SOIL by planting substrate, establish that taking into account open water surfaces for M. trifoliata growth and manage about 30cm of water depth control, then habitat creation for M. trifoilata will be successful.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.4
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• pp.288-294
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• 2012

The current growth of nano-industries has resulted in released nanoparticles entering into water and soil ecosystems via various direct or indirect routes. Physicochemical properties of nanoparticles differ from bulk materials, and nanomaterials influence the fates of nanoparticles and the interactions of living or non-living things in the environment. Microcosm analysis is a research methodology for revealing natural phenomena by mimicking part of an ecosystem under controlled conditions. Microcosm study allows for the integrated analysis of toxic effects and fates of nanoparticles in the ecosystem. Ecotoxicity studies of nanomaterials are steadily increasing, and microcosm studies of nanomaterials are currently beginning to surface. In this study, microcosm studies of nanomaterials in water and soil ecosystems were extensively investigated based on SCI(E) papers. We found that the microcosm studies have been reported in 12 instances, and mesocosm studies have been reported in only once until now. Advanced research was mostly evaluated at the microorganism level. But integrated analysis of nanotoxicity is required to research the interactions based of various species. Thus, our studies analysed the trend of microcosm studies on nanomaterials in water and soil ecosystems and suggested future directions of microcosm research of nanomaterials.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.5
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• pp.545-552
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• 2018

In this study, we performed a mesocosm experiment to estimate the mass balance of Nutrients (DIN, DIP) in a phragmites australis community. We developed 4 mesocosm tanks which is available to circulate seawater with adjustable tide levels and flooding times. Each of the mesocosm tanks were filled with phragmites australis and sediment from Jinudo in Nakdong Estuary. We investigated DIN, DIP concentrations in three layers (seawater-phragmites australis-sediment) to estimate the mass balance of Nutrients and biomass. Growth rates were also investigated. The results can be summarized as follows. 1) In spring, rhizome biomass was higher than that of aerial stem by about 6.3~9.7%. In summer, aerial stem biomass was higher than that of rhizome about 19.2~21.2 %. 2) Th Growth rate of phragmites in Mesocosm Tank A was faster than in Mesocosm Tank D by about 2 to 3 times for aerial stem and rhizome. 3) The Concentration of nutrients (DIN, DIP) in each mesocosm Tank showed 2~3 % variance in spring and summer. 4) The biomass in each mesocosm varied by about 23 % which was higher than the concentration variance for each mesocosm tanks.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.619-626
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• 2014

In this paper, it was constructed the halophyte Mesocosm experimental which was used tidal flat and dredged sediment as a substrate material. Depending on the vegetation and substrate material of Mesocosm, Mesocosm A(tidal flat sediment + Salicornia herbacea), Mesocosm B (only dredged sediment), Mesocosm C(dredged sediment + Salicornia herbacea). Monitoring was carried out of Warter quality factots(Chemical Oxygen Demand(COD), Total Nitrogen(T-N), Total Phosphorus(T-P), water temperature, salinity), Sediment factors(Chemical Oxygen Demand(COD), Total Nitrogen(T-N), Total Phosphorus(T-P)) and growth of Salricornia herbacea. Habitat Stability Index of vegetation was calculating by using the monitoring results. HSI of Mesocosm C was calculated from 0.87 to 0.95 as compared to the relatively high HSI in Mesocosm A, it was evaluated to be able to be used in the restoration and construction of the coastal salt marsh with dredged sediment.

• Journal of Wetlands Research
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• v.13 no.2
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• pp.355-362
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• 2011

Bog bean (Menyanthes trifoliata L.) is an endangered species in Korea and a perennial macrophyte with long rhizome, inhabiting in oligotrophic fen or edges of montane lakes. To decide appropriate substrate type for restoration of this plant, we investigated the effect of substrates (e.g. water, Sphagnum mat, paddy soil) on growth of bog bean. There were two water conditions on paddy soils: saturated and flooded. We planted 10cm rhizome in mesocosms and measured coverage, leaf area, leaf number and rhizome biomass. Bog bean growed until August in water and Sphagnum mat and until October in paddy soil. Rhizome biomass at the end of November were 49, 77, 239, and 312g in water, Sphagnum mat, paddy soil with water saturated, and paddy soil with water flooded conditions, respectively. The results indicate that bog bean can grow better in paddy soil which have higher nutrient than water or Sphagnum mat which represents natural habitat condition of bog bean. This reveals that actual ecological niche of bog bean is different from fundamental ecological niche in substrate. For successful restoration of bog bean in nutrient rich area, it is necessary to know the competitiveness of bog bean in various substrate conditions.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.353-361
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• 2013

An in situ mesocosm experiment was designed to investigate how exposure to ocean acidification by increased carbon dioxide affected the growth of juvenile oliver flounder (Paralichthys olivaceus). A total of 447 individuals were reared in the mesocosm experimental devices deployed at sandy-muddy bottom in the southern coast of East Sea for 43 days and divided into two groups: treatment group (223 individuals, $6.32{\pm}0.75$ cm, high-$CO_2$ environment) and control group (224 individuals, $6.34{\pm}0.84$ cm, natural $CO_2$ environment). The average values of pH and $CO_2$ concentration in the treatment device were $7.63{\pm}0.13$ and $1660{\pm}540$ ${\mu}atm$, respectively, while those in the control device were $8.07{\pm}0.05$ and $514{\pm}65$ ${\mu}atm$, respectively. There was no significant difference in mortality rate between treatment and control group, and the mortalities in two groups gradually decreased during the study period. But, the increase of size and weight of juvenile oliver flounder was higher in control group than treatment group, i.e., weight gain or growth rate was higher in control group. These results suggested that high $CO_2$ environments could have a significant negative influence on the early growth of juvenile oliver flounder.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.1
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• pp.74-80
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• 2019

In this study, pyrolyzed oyster shells at a low temperature ($350^{\circ}C$) were applied for a mesocosm experiment to confirm resulting changes in the properties of sediment. After creating a covering of oyster shells, an increase in ORP and decrease in ammonia in the overlying water was observed in an experimental case. The decrease of TOC in this experiment was due to the dilution of organic matter due to the addition of inorganic matter (pyrolyzed oyster shells). The decrease in the concentration of AVS was observed due to the adsorption of AVS by the surface of the oyster shells. From the results obtained in this experiment, it has been concluded that pyrolyzed oyster shells at a low temperature can be used for remediation of polluted sediment.

• Journal of Wetlands Research
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• v.22 no.1
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• pp.24-30
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• 2020

To assess the wetland systems' capability to reduce fine dust, we used an artificial wetland module of small-sized greenhouse (70cm W × 70cm L × 60cm H) which creates a closed system. Experiment was performed twice using four species in each experiment. Non-plantation, one species, or two species condition was created in each mesocosm. We measured air quality, primarily PM2.5 and PM10 at the initial open mesocosms and 1hr later since mesocosms were closed. The dry weight of vegetation was measured at the 2nd experiment. The decreased amount of PM2.5 and PM10 was 13.7±1.3 and 13.2±1.3 ㎍·m^-3hr^-1 in wetland condition and 15.0±1.4 and 13.8±1.5 ㎍·m^-3hr^-1 in dryland condition, respectively. In 2^nd experiment, the decreased amount of PM 2.5 and PM 10 in wetland condition was 13.7±1.3 and 9.2±1.5 ㎍·m^-3hr^-1, 15.0±1.4 and 8.8±1.4 ㎍·m^-3hr^-1 in dryland condition, respectively. Wetland showed higher removal effect due to its high productivity leading to more effective absorption of particulate matter. Furthermore, the aquatic characteristics of wetland system and high humidity helped purifying the air quality. This can be seen as another value of wetlands, which can be presented as one of the solutions to the problem of fine dust.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.11 no.2
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• pp.49-67
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• 2006

A mesocosm, an artificial tidal flat ecosystem, was constructed outdoors to simulate in situ physical and biochemical environmental conditions of natural tidal flat as much as possible. During the experiment from February to August 2004, the study was focused on the biogeochemical variations of superficial water and porewater after introduction of freshwater into the mesocosm. The mesocosm has three experimental conditions; SW-M-T: maintaining the saline water of approximately 20 psu; FW-M-T: complete exchange of freshwater ul the mesocosm with continuous mixing of water column: FW-NM-T: complete exchange of saline water to freshwater in the mesocosm without mixing of water column. Mass extinction of benthic macrofauna appeared due to drastic decrease of porewater salinity from 20 psu to less than 10 psu between the 63th and 91st day of freshwater introduction in FW-M-T and FW-NM-T. Throughout the periods, 7/8 of bivalves and 2/3 of polychaete populations have been extinguished in the sediment. In FW-NM-T, as temperature rises, both evident decrease of DO in water column and active release of DIP from sediment were observed. ${NO_3}^-$ was removed from water column into sediment throughout the periods. Therefore extremely low ${NO_3}^-$ was found during late spring and summer. Whereas ${NH_4}^+$ exhibited only $1/2{\sim}1/8$ of ${NO_3}^-$ concentration. Unexpectedly even after mass extinction of benthic macrofauna, we were not able to find high ${NH_4}^+$. This mesocosm study suggests that when fresh water introduce to natural tidal flat, its sediment activity functions as a potential source of DIP, but a sink of ${NO_3}^-$.