• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.165-172
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• 2002

We presents an hazard zonation mapping technique in karst terrain and its assessment. From the detailed engineering geological mapping. Controlling factors of sink hole and limestone cave formation were discussed and 4 main hazard factors affecting hazard potential are identified as follows: prerequisite hazard factor(distributions of pre-existing sink holes and cavities), geomorphological hazard factors(slope gradient, vegetation, and drainage pattern etc.) geological hazard factors(lithology, fracture patterns and geological structures etc.) and hydraulic conditions(hydraulic head, annual fluctuation of ground water table and composition of g/w water). From the construction of hazard zonation map along the Jecheon-Maepo area, and vertical cross-sectional hazard zonations specific tunnel site we suggest hazard zonation rating systems.

• Journal of Wetlands Research
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• v.8 no.2
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• pp.65-74
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• 2006

A study of the vascular hydrophyte communities and biomass was undertaken in the Bigumdo wetlands, Shinangun, from March to November, 2005. As a result, the vegetation was divided into 14 communities. Among them, emergent hydrophytes consisted of 6 communities, including Miscanthus sacchariflorus community, Phragmites communis community, Typha angustata community, Leersia japonica community, Paspalum disticum var. indutum community, and Persicaria thunbergii community, floating hydrophytes 5 communities including Hydrocharis dubia community, Nelumbo nucifera community, Euryale ferox community, Trapa japonica community and Nymphaea tetragona var. angusta community, free-floating hydrophytes 2 commuinties including Lemna paucicostata community and Spirodela polyrhiza community, and submergent hydrophyte 1 community, including Myriophyllum verticillatum community. Biomass was the highest at emergent hydrophytes and decreased along the life form, in the order like floating hydrophytes, submergent hydrophyte and free-floating hydrophytes. In addition, hydrophytes in the Bigumdo wetland showed the typical vertical zonation pattern like a natural swamp. These results were considered that the wetland of Bigumdo was characterized by the typical structure of aquatic plant ecosystem.

• Journal of Plant Biology
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• v.28 no.2
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• pp.149-164
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• 1985

Intertidal algal community of Muchangpo in western coast of Korea was investigated qualitatively and quantitatively. Seasonal changes of algal occurrence, dominant species in cover, vertical zonation pattern and biomass were analysed. A total of sixty-four species of marine algae, one blue-green alga, three green algae, nineteen brown algae and forty-one red algae, were identified. The dominant species in cover were Sargassum thunbergii, Gelidium divaricatum and Pelvetia siliquosa throughout the year. Gloiopeltis furcata was abundant at upper and middle littoral zones and Corallina pilulifera at lower littoral zone. Classification by unweighted pair-group average method and ordination by reciprocal averaging based on the cover data indicated that, on the whole, the intertidal algal vegetation showed different patterns along tidal levels. Seasonal fluctuations of mean biomass were 57.2~92.8 g-dry/$m^2$, and the highest in summer and the lowest in spring season. Seasonal change of community structure was also discussed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.878-885
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• 2013

Seasonal variation in marine macroalgal community structure was examined at the intertidal zones of Heuksando and Hongdo, Shinan, Korea, from July 2008 to May 2009. In total, 86 macroalgal species were identified, including 12 green, 19 brown, and 55 red algae; 67 species at Heuksando and 70 species at Hongdo, were observed. Annual seaweed biomass was 252.44 g dry $wt/m^2$ at Heuksando and 217.67 g dry $wt/m^2$ at Hongdo. The dominant seaweed in importance value (IV > 15) differed between the sites: Sargassum thunbergii at Heuksando and Corallina pilulifera at Hongdo. The vertical distribution pattern of seaweeds from the upper to lower intertidal zones at Heuksando was Gloiopeltis spp., Ulva spp. - S. thunbergii, S. fusiforme, Hildenbrandia rubra - S. thunbergii, C. pilulifera. On the rocky shore of Hongdo, seaweed zonation was distinct: Porphyra yezoensis, Gloiopeltis spp., Ulva spp. - C. pilulifera, S. fusiforme, Myelophycus simplex - Chondrus ocellatus, C. pilulifera, and Carpopeltis affinis. Annual seaweed coverage, richness index (R), evenness index (J'), and diversity index (H') values were greater at Hongdo (41.35%, 12.82, 0.59, and 2.50 respectively) than at Heuksando (31.54%, 11.93, 0.44, and 1.87 respectively), which may indicate that the seaweed community at Hongdo is more stable relative to the one at Heuksando.

• Korean Journal of Ecology and Environment
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• v.38 no.1 s.110
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• pp.30-44
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• 2005

To investigate the flora and vegetation structure of vascular plants in the littoral zone of Paldang Reservoir, from April, 2003 to April 2004, nine sampling sites were selected. Along the Paldang Reservoir, 128 taxa, consisted of 51 families and 96 genera, were identified, among them, hydrophytes were confirmed as 38 taxa, which was comprised 29.7% to total taxa, whereas hygrophytes were 44 taxa and terrestrial plants were 46 taxa. Emergent hydrophytes consists of 21 taxa, including Phragmites australis and Typha angustifolia, and next, submerged hydrophytes were 8 taxa. However, the kinds and vegetation area of submerged hydorphytes were reduced compared to previous studies. In the littoral zone of Paldang Reservoir, the aquatic vegetation was widely developed near Dumulmori, Yangsuri, and Kwangdong Bridge, downstream of Kyungancheon. The average number of hydrophyte per sampling sites were 2.7 taxa, whereas hygrophytes were 2.5, and land plants were 1.8. In addition, the hydrophytes in the littoral zone of Paldang Reservoir showed the typical vertical zonation pattern like a natural swamp. These results mean that the littoral zone of Paldang Reservoir has the typical characteristics of aquatic plant ecosystem.