• Journal of Ecology and Environment
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• v.31 no.3
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• pp.213-223
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• 2008

The increasing area of abandoned rice fields could provide new opportunities for wetland restoration in Asia. However, it is unknown how quickly or completely abandoned rice fields will recover from agricultural disturbances. We assessed water quality and plant community succession in abandoned rice fields with different hydrology in a mountain valley to understand the effects of hydrological regime on recovery. Water level, soil redox potential, water quality, plant composition, and primary production were measured. The sites, coded as D6, N13, and N16, had been recovering for 6, 13, and 16 years by 2006. N13 and N16 have been recovering naturally whereas D6 has been drained with a nearby dike and was tilled in 2001. The typical hydroperiods of D6, N13, and N16 were no surface water, permanently flooded, and seasonally flooded, respectively. The major change in vegetation structure of both D6 and N13 was the replacement of herbaceous species by woody species. Drawdown accelerated this change because Salix koreensis grew better in damp conditions than in flooded conditions. Phragmites japonica reduced plot-level plant species richness. The removal efficiency of $NH_4-N$, $NO_3-N$, and $PO_4-P$ from water varied seasonally, ranging between -78.8 to 44.3%, 0 to 97.5%, and -26.0 to 44.4%, respectively. In summary, abandoned rice fields quickly became suitable habitat for native wetland plant species and improved regional water quality. Variation among our sites indicates that it is likely possible to manage abandoned rice fields, mostly through controlling hydrology, to achieve site-specific restoration goals.

• Korean Journal of Environmental Agriculture
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• v.22 no.4
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• pp.251-254
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• 2003

Phosphorous removal rate and emergent plant growth were examined of a surface-flow constructed treatment wetland system, whose dimensions were 31 meter in length and 12 meter in width. The system was established on floodplain in the down reach of the Kwangju Stream in Korea in one and half months from May to June 2001. Cattails(Typha angustiflora) were transplanted in the system. They were dug out of natural wetlands and stems were cut at about 40 cm height from their bottom ends. Water of the Kwangju Stream were funneled into it via a pipe by gravity flow and its effluent were discharged back into it. The stems of cattails grew from 45.2 cm in July 2001 up to 186 cm in September 2001 and the number of cattail stems per square meter increased from 22 in July 2001 to 53 in September 2001. The early establishment of cattails was good. Volume and water quality of inflow and outflow were analyzed from July 2001 through December 2001. Inflow averaged $40\;m^3/day$ and hydraulic retention time was about 1.5 days. The concentration of total phosphorous in influent and effluent was 0.85 mg/L, 0.41 mg/L, respectively. The average removal rate of total phosphorous in the system was about 52%. The retention efficiency was slightly lower, compared with that in surface-flow wetlands operating in North America, whose retention efficiency was reported to be about 57%. The lower abatement rate could result from the initial stage of the system and inclusion of two cold months into the six-month monitoring period. Root rhizosphere in wetland soils and litter-soil layers on bottoms were not properly developed. Increase of standing density of cattails within a few years will establish both root zones and substrates beneficial to the removal of phosphorous, which may lead to increase of the phosphorous retention rate. The system was submerged one time by heavy storm during the monitoring period. The inundation, however, scarcely disturb its environment.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.2
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• pp.70-77
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• 1999

This study was carried out to suggest an effective method for the rehabilitation of Close-to-Nature River and artificial wetland. The results on the revegetation methods by seeding and sodding of Phragmites japonica, Miscanthus sacchariflorus, Themeda triandra, and Pennisetum alopecuroides were summarized as follows. Seed germination of Phragmites japonica was 76.3% at $30^{\circ}C$, that of Miscanthus sacchariflorus was 68.7% at $20^{\circ}C$, that of Themeda triandra germinated 52.3% at $25^{\circ}C$, $30^{\circ}C$ constant temperature and that of Pennisetum alopecuroides germinated 86.7% at $30^{\circ}C/20^{\circ}C$ alternating temperature. Seed germination of Pennisetum alopecuroides exceeded 80% at $20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$ constant temperature and $25^{\circ}C/15^{\circ}C$ alternating temperature. At 60 days after seeding, the ground coverage of Phragmites japonica, Miscanthus sacchariflorus, Themeda triandra, and Pennisetum alopecuroides reached 81%, 81 %, 74%, and 86% respectively in the soil media of vermiculite and peatmoss(1 : 1 by volume). In the results of sod experiment, Phragmites japonica, Miscanthus sacchariflorus, Themeda triandra, and Pennisetum alopecuroides were formed sod completely in soil composition type of vermiculite and peatmoss(1 : 1, v/v). Thus this media seems to be best sad production media for rehabilitation works of Close-to-Nature River and man-made wetlands. Phragmites japonica and Miscanthus sacchariflorus were not significantly different in shoot height and the number of tillers by different planting distance for the first one year of experiment. Pennisetum alopecuroides shows high possibility to be used for Close-to-Nature River rehabilitation works by seeding.

• Journal of Wetlands Research
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• v.14 no.2
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• pp.181-192
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• 2012

Dae Dong Stream basin has been selected and operated as a representative experimental basin of UNESCO IHP since year 2007. It is located at Daejeon Metropolitan city, Korea and hydrologic data such as precipitation, runoff, and water quality have been being collected and provided after establishing the monitoring plan as an experimental basin for city/disaster prevention. In this study, runoff characteristics for non-point sources of rainfall-runoff process from urban stream basins were analyzed using the flow and water quality data measured during the year 2011. As an operation result for the test subjected basin, rating curves at Panam Bridge and at Chulgap Bridge were prepared, and to compare runoff characteristics of non-point source by precipitation, by estimating the Event Mean Concentration(EMC) for 10 water quality items, runoff characteristics of non-point source per different observation points as per the precipitation, antecedent rainfall, and land utilization status were analyzed.

• Korean Journal of Plant Resources
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• v.24 no.4
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• pp.395-403
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• 2011

This study was conducted to investigate the habitat positional environment and vegetation properties of Mankyua chejuense. The habitats were classified into two types depending on the depth of the habitat, the ratio of rock exposure, the dominant species and the surrounding vegetation, which affected the vegetation of the habitats. The habitats with a high ratio of rock exposure showed a distinctive geographical boundary to the adjacent region and most of them were composed of trees that grow in humid environment. On the contrary, in the soil-rich habitats, the depth was shallow, soil layer was well developed, and the trees were introduced from the adjacent areas. However, the dominant species in the herbaceous layer were aquatic plants, which indicated that the habitats had the properties of wetland. Therefore, it was found that thes habitats of Mankyua chejuense have the properties similar to those of marshland. For the preservation of Mankyua chejuense, it is very important to make the habitats maintain such properties of wetland.

• Journal of Soil and Groundwater Environment
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• v.24 no.4
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• pp.1-10
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• 2019

Recently, groundwater contamination by mixed occurrence of arsenic (As) and nitrate ($NO_3{^-}$) has been a serious environmental issue all around world. In this study, we investigated the microbial As(III) oxidation characteristic under denitrification process to examine the feasibility of the microbial consortia in wetland sediment to simultaneously treat these two contaminants. The detail objectives of this study were to investigate the effects of $NO_3{^-}$ on the oxidation of As(III) in anaerobic environments and observe the microbial community change during the As oxidation under denitrification process. Results showed that the As(III) was completely and simultaneously oxidized to As(V) under denitrification process, however, it occurred to a much less extent in the absence of sediment or $NO_3{^-}$. In addition, the significant increase of As(III) oxidation rate in the presence of $NO_3{^-}$ suggested the potential of As oxidation under denitrification by indigenous microorganisms in wetland sediment. Genera Pseudogulbenkiania, and Flavisolibacter were identified as predominant microbial species driving the redox process. Conclusively, this study can provide useful information on As(III) oxidation under denitrifying environment and contribute to develop an effective technology for simultaneous removal of As(III) and $NO_3{^-}$ in groundwater.

• Journal of Species Research
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• v.11 no.1
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• pp.10-21
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• 2022

Two strains of cyanobacteria were isolated from the soil of Seodaemun-gu, Seoul and from the gravel of the Ansung Stream, Gyeonggi Province, Korea, respectively. They were identified as Pantanalinema rosaneae and Alkalinema pantanalense under the Leptolyngbyaceae through the morphological, ecological, and molecular analyses and first reported in Korea. Belonging to the Leptolyngbya morphotypes, they are thin filamentous cyanobacteria and morphologically indistinguishable cryptic species. The strains of P. rosaneae and A. pantanalense isolated in Korea revealed the same cluster as their type species in the phylogenetic analysis using the 16S rRNA gene sequences, and similarities in the secondary structures of 16S-23S ITS sequences. Although both P. rosaneae and A. pantanalense were collected from water samples in the Pantanal wetland of Brazil, the P. rosaneae obtained in Korea, was soil-dwelling subaerophytic species whereas A. pantanalense was epilithic species living on gravel in the freshwater. Therefore, they are considered to have an extensive habitat.

• Journal of Environmental Science International
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• v.22 no.11
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• pp.1421-1431
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• 2013

This study was conducted for clarifying distribution and characteristics of marshy Ericaceae plants on Mt. Changbai in China. The marshy Ericaceae plants in wetland of Mt. Changbai were investigated on about 1400 m altitude. This region is various developmental wetlands and vegetation mixture of needle-leaf trees and broad-leaf trees. This region also is start point of the coniferous forest zone in Mt. Changbai. As results of these researches, L. palustre var. diversipilosum and L. palustre var. decumbens populations were investigated in Larix olgensis var. amurensis community. R. lapponicum subsp. parvifolium var. parvifolium community appeared as a typical community. Environmental conditions of L. palustre var. diversipilosum and L. palustre var. decumbens populations' habitats are more soil humidity and shade condition. R. lapponicum subsp. parvifolium var. parvifolium community habitat, however, has more deposits and humidity condition. Therefore when the plants were cultivated, we should recognize the growth condition such as maintenance of humidity and control deposits. The flora of marshy Ericaceae species habitats was investigated as 28 families, 49 genera, 45 species, 14 variety, 1 forma, 1 sub-species, and total 61 taxa.

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

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.1
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• pp.1-13
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• 2010

This study was accomplished to identify and analyze vegetation structure of Mountainous Wetlands in Dan-yang and around area, and surveyed from September to November, 2006. 6 sites of total 16 potential Mountainous Wetlands by GIS based wetland forecasting system (Korea National Arboretum, 2006) were identified as wetlands throughout field survey by the indicators such as hydrology, soil and vegetation. By classification system of Korea National Arboretum (2006), types of wetlands were classified into 3 slope-types and 3 flat-types. To understand vegetation structure of wetlands, height, DBH (diameter at breast height), DI (Dominance Index), sociability and constancy were surveyed and the projection diagram and charts ware drawn. As results, Salix koreensis in woody plant layer and Persicaria thunbergiiin and Juncus effusus var. decipiens in herb layer were surveyed as broadly distributed species. The wetlands of Dan-yang around area were similar to those of Chung-ju around area, but the species of plants and hydrology conditions were different. This study is mainly focused on vegetation condition of Mountainous Wetlands. But, further studies on functional assessment for management and restoration of wetlands were necessary.