• Landscaping Tree
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• s.124
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• pp.56-59
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• 2011

• Korean Journal of Environment and Ecology
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• v.32 no.1
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• pp.66-76
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• 2018

This study surveyed the species and population of dragonflies in 20 study sites in the Junam wetland in May and July 2015 to investigate the relationship between the dragonflies and the inhabited environment. We measured the environmental factors such as the area of emergent plants, the area of floating and floating-leaved plants, the area of water surface, the area of water plants, and the nearby land-use type and analyzed the relationship to the dragonfly species, population, and diversity index. We found 757 dragonflies belonging to 21 species of 6 families. The area of floating and floating-leaved plants and the area of water surface affected the species diversity. The area of floating and floating-leaved plants and the area of surface water, in particular, showed the positive correlation with the species richness and the dominance value, respectively. The area of water surface showed the negative correlations with Shannon's diversity index and evenness. Among the type of surrounding land-uses, the dry fields and orchards showed significantly lower average species richness than wetlands. Among the species, Cercion calamorum and Crocothemis servilia were positively correlated with floating and floating-leaved plants. Cercion v-nigrum and Epophthalmia elegans were positively correlated with the area of water surface, and Ischnura asiatica and Ceriagrion nipponicum were negatively correlated. The recent uncontrolled proliferation of lotus colony in the Junam wetland is likely to affect greatly the species composition of dragonflies which have a close relationship with plant species.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2007.05a
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• pp.203-206
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• 2007

부유녹조와 갯버들 및 부레옥잠이 수질에 미치는 영향을 탐구하기 위해 5월 초에서 6월 말까지 실험실 수조의 수질변화를 고찰하면서 얻은 결과는 다음과 같았다. 부영양화가 진행되는 물에 수변식물인 갯버들과 수생부엽식물인 부레옥잠은 상호 혹은 단독으로 작용하여 DO, pH, SS, 탁도, 입자수 농도, Chl a 농도를 어느 시점에서 큰 폭으로 감소시켰고 갯버들과 부레옥잠의 상호작용시 그 효과가 가장 크게 나타났다. 부유녹조 단독으로는 DO와 pH 등을 서서히 감소시켰다. 이 결과로부터 갯버들 및 부레옥잠은 부유녹조와 경쟁관계가 되어 수질개선에 상당한 영향을 미칠 수 있는 것으로 추정된다.

• Korean Journal of Plant Resources
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• v.12 no.4
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• pp.303-311
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• 1999

This study had been performed to clarify the distribution of specific plants and hydrophytes in the 27 sites of drainage basins located in Youngsan River at the period of June 1997 to July 1999. Hydrophytes were composed of 32 familis 86 species and hygrophytes 36 familis 135 species. Among hydrophytes, emerged plant, floating-leaved plant, submerged plants and free floating hydrophytes were 52, 15, 12, and 7 species respectively in this investigation. Threatened species were Drosera rotundifolia, Utricularia racemosa, Utricularia bifida, Utricularia japonica, Hydrocharis dubia, Endangered species were Brasenia schreberi and Euryale ferox.

• Korean Journal of Environment and Ecology
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• v.17 no.1
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• pp.44-55
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• 2003

The wetland in the city could be mainly divided into the deep water type and the abandoned paddy type, so this study was conducted to analyze characteristics between the two types of the wetland. The former sample site was located near the Olympic village in Songpa-gu of Seoul, and the latter sample site was in front of the Mt. Bukhan fortress in Eunpyeong-gu of Seoul. The actual vegetation, vascular plants, and avian fauna were researched. In the actual vegetation, the deep water type had the broad surface of water and the emerged plant as Phragmites communis have grown widely, but the abandoned paddy type had the narrow sur-face of water and hydrophyte as Persicaria thunbergii have grown widely. It might be judged because the water depth of the abandoned paddy type were shallow wholly. And the floating-leaved plants and the free-floating planktonic plants were not observed such as Nymphaea tetragona var. angusta, Lemna paucicostata in the abandoned paddy type wetland. The wild birds were mainly observed at the edge of the wetland(at the edge of woodland) in the abandoned paddy type, but were observed equally in the deep water type. 28 families 433 species were observed at the former site and 32 families 365 species were observed at latter site. It was judged that the various topographical structure(habitat diversity) might make all items various.

• Korean Journal of Environment and Ecology
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• v.30 no.3
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• pp.308-319
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• 2016

The purpose of this study is to identify distribution patterns of hydrophytes in the Mokpo wetland in relation to the depth of water. Sample surveys were conducted based on plant species distribution status and water depths at 274 spots. This study also developed a detailed depth distribution map for Mokpo wetland, which was never done in any previous studies. Through this study, it was found that the average depth of the wetland was 77cm (${\pm}29cm$) and the maximal depth was 157cm. The outer edge was no deeper than 60cm and the center approximately 120~130cm in depth, forming a concave bowl-like shape. This research confirmed inhabitation of 6 types of submerged plants (Verticillate hydrilla, Vallisneria natans, Najas graminea, Potamogeton cripus, Ceratophyllum demersum, and Potamogeton brechtoldi), and three types of floating leaved plants (Euryale ferox, Hydrocharis dubia and Trapa japonica) in the surveyed areas of the wetland. The distribution of these hydrophytes showed a statistically significant difference (${\chi}^2=982.2$, df = 8, p < 0.01), which confirms the fact that distribution varies based on environmental conditions. The most frequently observed species was Trapa japonicas at 244 times, and it showed a distribution pattern by which coverage increased with greater depth, as was also seen in the case of Potamogeton cripus. Five species-Euryale ferox, Hydrocharis dubid, Verticillate hydrilla, Najas graminea, and Ceratophyllum demersum-showed a negative correlation to depth, by which coverage decreased with increasing depth. It has been shown that fundamentally, the distribution of hydrophytes based on depth is affected by ecological factors, but also reflects the environmental properties of Mokpo wetland.

• Journal of Wetlands Research
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• v.13 no.3
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• pp.657-664
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• 2011

The plant community of water`s edge was investigated using the methodology of the Z-M school of phytosociology, from March to October, 2008, 2011. The results were obtained as follow ; hygrophyte hydrophye of 2008 year of this area consist of 38 taxa : 1 varieties, 37 species, 31 genera, 21 families and 14 orders, hygrophyte hydrophye of 2011 year of this area consist of hygrophyte 15 species, 13 species were reduced by approximately 13.33%. And emerged hydrophyres did not show a change. 9 species, 4 species of Floating-Leaved hydrophyres 55.56%, Submerged hydrophyres of the 4 species, 1 species, 75%, Free-Floating hydrophyres remarkable I the 3 species was reduced to 33.33%, respectively. Plants Community of the water's edge was classified into 16 communities as follows; (Leersia japonica community, Spirodela polyrhiza community, Miscanthus sacchariflorus community, Hydrocharis dubia community, Zizania latifolia community, Paspalum distichum var. indutum community, Leersia japonica-Hydrocharis dubia community, Salix glandulosa community, Trapa japonica community, Humulus japonicus community, Nelumbo nucifera community, Carex dimorpholepis community, Salix koreensis community, Trapa japonica-Spirodela polyrhiza community, Persicaria thunbergii). Higher in 2011 than in 2008, the ratio was reduced to Leersia japonica community. Between July-August by a sudden change in the rate of water storage changes in vegetation are thought to have appeared.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.49-56
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• 2010

Euryale ferox is only annual hydrophyte among endangered plants in Korea and its seed is high valuable medicinal material. This studies were carried to find out key factors that made E. ferox endanger in Korea and to apply the results for effective management of the natural wetlands inhabited by E. ferox. We investigated the distributed sites reported by previous studies and classified the distribution-affected factors into three categories, eutrophication(hypothesis 1), soil accumulation(hypothesis 2) and increasing of water level(hypothesis 3) in the habitat. These three hypotheses were tested in the field and explained the results with the morphological characteristics of seed germination stages of E. ferox. The geographical distribution ranges of E. ferox diminished at a rate of $1^{\circ}$ latitude with about 10 natural wetlands for last 30 years. Water eutrophication in the wetland had a positive effect on the establishment of E. ferox. But higher in soil accumulation and water depth, then lower in the establishment rate of E. ferox. These results indicate that water depth in the wetland must be below 50cm during the germination season, especially in May and emergent hydrophytes filter zone is need to protect soil accumulation from soil erosion within its watershed for the effective management of wetland with E. ferox.

• Journal of Wetlands Research
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• v.10 no.1
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• pp.31-37
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• 2008

A study of the vascular hydrophyte communities was undertaken in the wetlands of Imjado, Shinangun, from March to November, 2006. As a result, the vegetation was divided into 15 communities. Among them, emergent hydrophytes consisted of 9 communities, including Phragmites communis community, Typha angustata community, Paspalum disticum var. indutum community, Sparganium erectum community, Oenanthe javanica community, Echinochloa crusgalli var. crusgalli community, Juncus effusus var. decipiens community, Aneilema keisak community and Persicaria thunbergii community, floating hydrophytes 1 community Trapa japonica community, free-floating hydrophytes 2 communities including Lemna paucicostata community and Spirodela polyrhiza community, and submergent hydrophyte 2 community, including Myriophyllum verticillatum community and Potamogeton distinctus community. These results were considered that the wetland of Imjado was characterized by the typical structure of aquatic plant ecosystem.

• Korean Journal of Environment and Ecology
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• v.17 no.4
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• pp.346-359
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• 2004

Flora was investigated in the Dongbok stream area of hwasun-gun, Jeonllanam-do from February in 2002 to August, were identified as 206 taxa; 75 families,158 genera,174 species,31 varieties and 1 form of plant. Hydrophytes of research site was investigated total, 29 taxa; 16 families, 23 genera, 26 species and 3 varieties. Emerged plants, submerged plant, floating leaved plants and floating plants among the hydrophytes was classified 22, 4, 2 and 1 taxa respectively. Naturalized plants of research site was investigated total, 19 taxa; 10 families, 17 genera, 17 species, 2 varieties. Based on the list of rare and endangered plants from the Forest Research Institute and the Ministry of Environment 1 species Sparganium stoloniferum were recorded in the studied area.