• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.4
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• pp.266-273
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• 2016

Two-dimensional hydraulic experiments were performed to assess the impact of artificial seaweed on wave energy attenuation, and coastal erosion prevention. In this experimental study, erosion geometry and wave reflection coefficients were determined for normal and stormy incident waves, with and without artificial seaweed. The coastline of beaches without artificial vegetation was observed to retreat, and the longshore bar height increased in normal and stormy conditions. Through the introduction of artificial seaweed (of widths 0.8 m, and 1.6 m), the coastline was found to advance in the offshore direction due to material deposition. From these results, it is shown that artificial seaweed alters the cross-section of beaches, such that it is possible to prevent coastline erosion.

• Journal of the Korean Geographical Society
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• v.47 no.2
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• pp.193-207
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• 2012

This study discussed characteristics of Shindu Coastal Dune as habitat, and relationship between geodiversity and biodiversity. It was identified spatio-temporal variation of incoming nutrients depended on geomorphic differences of foredunes. The main incoming path of nutrients into coastal dune was considered as influx with movement of wind blown sands from the beach and tidal f lat. Concentrations of Na, Mg, K, Ca, and P in blown sands were compared. Concentrations of Na, Mg, and K showed high and irregular pattern in favorable condition of influx of blown sand. So these nutrients were related with geomorphic characteristics of foredunes. However, Na was also influenced by other factor such as salt spray. P was independent from effects of sea water and blown sands. In the case of Ca, a large coastal dune system rather than localized forms of foredunes made differences in the variation. Due to differences in spatio-temporal variation of nutrients, patterns of major vegetation could be inferred to appear differently. This study shows geomorphic dynamics of coastal dunes as habitat, and will provide information for coastal dune management and for understanding biological distribution and growth pattern in coastal dune.

• Korean Journal of Medicinal Crop Science
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• v.17 no.2
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• pp.139-144
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• 2009

This study was conducted to evaluate the vegetation, distribution and growth pattern of Glehnia littoralis community by the DCA ordination method in eastern coast of Korea. The number of plant species growth with G. littoralis in natural habitat was found 51 taxa, and species of high frequency among 51 taxa was Ixeris repens, Calystegia soldanella, Carex kobomugi, Elymus mollis, Lathyrus japonica and Zoysia macrostachya. Indicator species of Z. macrostachya, Linaria japonica, C. soldanella, I. repens, Carex pumila, Artemisia capillaris, Oenothera biennis, L. japonica and E. mollis in G. littoralis community was differential species of syntaxonomy. C. kobomugi, Z. macrostachya, E. mollis, Cynodon dactylon and L. japonica was the distribution in dryness sand and moisture sandyloam, I. repens, C. soldanella, L. japonica and C. pumila was the distribution in dryness sand. In coastal dune, I. repens, C. soldanella, Salsola komarovi and G. littoralis combined strength of the distribution, and sand of coast was typical of the habitat.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.1
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• pp.83-90
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• 2016

A subtidal marine benthic algal vegetation at Ulleungdo Island, the eastern coast of Korea was investigated to clarify the community structure and vertical distribution by quadrat method at seven stations in May and August 2014. The total number of marine algal species was 148 species composed of the green algae of 12 species, the brown algae of 40 species and the red algae of 96 species. Mean biomass in dry weight was $94.8g\;dry\;weight\;m^{-2}$ in study sites, $98.1g\;dry\;weight\;m^{-2}$ in upper tidal level, and $86.6g\;dry\;weight\;m^{-2}$ in middle level. The R/P and (R+C)/P value reflecting flora characteristic were 1.9 and 2.3, respectively. Three groups produced by cluster analysis, one including sites Neunggeol, Daepung, Jukdo, second including sites Gongam, Ssangjeongcho and the other including sites Gwaneum, Hangnam, showed meaningful difference in similarity (about 40%), each other. The number of marine algal species and biomass in Ulleungdo Island area were markedly reduced comparing that in the previous studies. This result may suggest probably change of algal vegetation in future, considering the physical and chemical pollutions loaded in the coastal marine environment of this area.

• Journal of computational fluids engineering
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• v.17 no.3
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• pp.87-92
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• 2012

The presence of a layer of vegetation which is relevant in river engineering or coastal engineering can modify the overall flow resistance, turbulent characteristics of flow. The patch of vegetation can be modelled and studied in a simple porous cylinder by previous researchers. Fully three dimensional Large Eddy Simulation is conducted in flow past a porous cylinder with a solid volume fraction (SVF) 0f 20%. The porous cylinder of diameter D contains 89 smaller cylinders which diameter is 0.048D in a regular staggered way. Reynolds number based on porous cylinder diameter D and the bulk velocity is 10,000. The large scale shedding is qualitatively similar to the one observed in the non-porous case (SVF=100%). The difference in the dynamics of the separated shear layer and the streamwise flow penetrating through the porous cylinder are compared with those in the non-porous cylinder. In particular, the wake billows form a larger distance from the back of the porous cylinder.

• Journal of Navigation and Port Research
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• v.29 no.1 s.97
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• pp.113-118
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• 2005

We studied field observation and countermeasure about the effluent of sediment and nutrient materials on the Okinawa Ishigaki Coast according rainy season though this observation, we found out the analysis of outflow topography, intensity of rainfall and effects on the tide, the property of effluent materials ete. The sediment and nutrient concentration of the Okinawa Ishigaki coast are different on the regional sites according to vary with time variation of intensity of rainfall and the ebb and flow. We could confirm to vary with utilized waterways land area and distribution of surrounding vegetation.

• Journal of Ecology and Environment
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• v.42 no.1
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• pp.12-19
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• 2018

Background: The objective of this study was to determine the relationship between soil environmental factors and halophyte distribution in the west coast of South Korea. Soils of our study sites were categorized into two groups: salt marsh and estuary marsh. Results: Salinity was higher in the salt marsh group than that in the estuary marsh group. However, total nitrogen, silt, and clay contents were higher in the estuary marsh group than those in the salt marsh group. Although altitude had a wider range in the salt marsh group, the mean altitude was higher in the estuary marsh group than that in the salt marsh group. Annual halophytes of seed propagation species were distributed parallel to the coast line on salt marsh. Higher coverage of vegetation was found in the area closer to the coast line. Plant density was higher near dead parental plants in estuary marsh, showing less difference in area that was more distant from the coast line. Conclusions: Results of canonical correspondence analysis (CCA) for vegetation distribution and sediment environmental factors and germination analysis in the coast line showed significant relationship with halophyte distribution. Therefore, they can be used as an indicator of coastal plant movement due to sea level rise.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.220-227
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• 2018

Background: To understand the ecological characteristics of floating mat in which endangered species of Iris laevigata and Menyanthes trifoliata inhabit, we surveyed the vegetation and water environments of a floating mat wetland and examined the relations between ecological characteristics of the mat. Results: Although Phragmites australis and Zizania latifolia were found at all experimental quadrats (n = 61) as the major vegetational components of the floating mat wetland, they showed relatively poor growth performances in terms of shoot height (< 2 m) and biomass production (<$300g/m^2$) compared with those in soil-based wetlands because of oligotrophic water condition. The competitiveness and distribution of P. australis and Z. latifolia seemed to be determined by water level difference by micro-topography rather than water chemistry. Conclusion: P. australis and endangered plant species mainly occurred in the area of relatively shallow water, whereas Z. latifolia and deep-water species such as Scirpus fluviatilis mostly inhabit in the area of deep water on the floating mat. Continuously maintained water level and oligotrophic water condition in the floating mat appeared to be important environments for endangered species such as I. laevigata and M. trifoliata.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.2
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• pp.13-35
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• 2017

This study was carried out to analyze vegetation structure and change of the disturbed area in forest ecosystem(FE), riparian ecosystem(RE) and coastal ecosystem(CE) related to Regional Ecological Network at Chungnam province through constancy and dominance analysis, species diversity index, similarity index and canonical correlation analysis. Data were collected from April to October in 2015. As a result of constancy and dominance analysis of forest disturbed area, non-effective species(NES) was 30 species(17.0%), exported species(ES) was 98 species(55.7%) and imported species(IS) was 48 species(27.3%) among the total 176 species, respectively. In riparian disturbed area with total 139 species, there were 16 NES(11.5%), 98 ES(70.5%) and 25 IS(18.0%) respectively. In coastal disturbed area with 140 species, there were 20 NES(14.3%), 88 ES(62.9%) and 32 IS(22.9%) respectively. In all types of disturbed areas, the ratio of ES was higher than IS. As a result of species diversity, species richness and shannon's diversity index of disturbed area decreased in all kinds of crown strata such as tree, subtree, shrub and herb layer compared to the control area. As a result of similarity index, that of each type between control site and disturbed site was 0.374 in FE, 0.329 in CE and 0.259 in RE in the order. As a result of the CCA analysis, the number of present species, vine plants ratio and exported species ratio in disturbed area of FE and RE were decreased, and the naturalized plant ratio, imported species ratio and herb ratio were increased. But environmental factors of CE were not shown any clear tendency. In conclusion, many species occupied in control site disappeared into the disturbed area, and the naturalized plants and herb species were abundantly imported in the area. Therefore, it was considered that this study could be applied to the development of long-term and short-term ecological restoration techniques in view of vegetation changes.

• Journal of Wetlands Research
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• v.15 no.4
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• pp.543-553
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• 2013

In Korea, there have been many studies and progresses on various types of pilot scale or commercialized field scale Best Management Practices(BMP) during the last 10 years. Runoff characteristics of diffuse pollutants from different land uses are well identified and documented. However, for the coastal area connected directly with shoreline, runoff patterns and management schemes of non-point pollution were not fully studied. Recently, coastal area is emerging as a new development axis especially in west coast side of Korea such as Incheon city and Chungnam province, thus urbanized area rapidly increased but there are no buffer zones and BMP facilities to aim at preventing direct discharge of the first flush into coastal sea and beaches. In this study, parking area in Deacheon harbor, Boryeong City in Chungnam Province was selected and rainfall runoff was monitored for two year period in order to examine run-off features from which proper type of BMP suitable for coastal area is proposed. Coastal area usually has a low ground water level and consists of plain land, so that large scale BMP such as storm water retention pond and wetland requiring great excavation works is not best management plan. In addition, monitoring study shows that storm water from the paved parking area has a high salinity compared with those in storm water from the inland. High salinity is detrimental for the vegetation. Therefore, BMP employing least vegetative cover and also in terms of maintenance is a good option such as infiltration trench and porous pavement.