• The Korean Journal of Malacology
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• v.28 no.1
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• pp.29-35
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• 2012

Growth patterns of the Manila clam, Ruditapes philippinarum in each tidal level were studied in the intertidal zone in Tae-an on the west coast of South Korea from April to August 2009. Environmental factors and the specimens of R. philippinarum were monthly collected at three intertidal locations: low intertidal zone, low-middle intertidal zone and middle intertidal zone. Temperature of sediment in low intertidal zone were lower than those in other intertidal locations. Concentrations of Chl-${\alpha}$ were not significantly different between in each tidal level. Exposure hours in low intertidal zone were shorter than those in other intertidal locations. Density of each year class in low intertidal zone were higher than those in low-middle intertidal zone and middle intertidal zone. Growth factors of R. philippinarum in low intertidal zone were better than those in other intertidal locations. The growth rate of under one year class individuals of low intertidal zone were higher than those in low-middle intertidal zone and middle intertidal zone, before the main recruitment period of R. pilippinarum. Although the growth patterns of R. philippinarum may be affected by various environmental factors, we suggests that the exposure duration is the main affect in the growth patterns of R. philippinarum in intertidal zone.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.1
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• pp.65-75
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• 2012

To study the difference in growth characteristics between intertidal and subtidal eelgrass Zostera marina populations, environmental factors and changes in tissue carbon (C) and nitrogen (N) contents in eelgrass from the lower intertidal and upper subtidal zones were surveyed monthly in the Seomjin Estuary from May 2003 to December 2004. Water temperatures, water column nutrient concentrations, sediment pore water, and ammonium and phosphate concentrations showed no significant differences between intertidal and subtidal zones. Sediment pore water nitrate+nitrite concentrations were slightly higher in the intertidal zone than in the subtidal zone. Average monthly exposure times in the intertidal and subtidal zones were $42.4{\pm}5.8h\;month^{-1}$ and $15.3{\pm}3.5h\;month^{-1}$, respectively. Eelgrass leaf N content decreased from March to August and increased from September to February in the subtidal zone, whereas these trends were not observed in the intertidal zone. Eelgrass rhizome C content increased from April to September and decreased from October to March in the subtidal zone, whereas those tendencies were not recorded in the intertidal zone. Eelgrass rhizome C:N ratios showed a strong reverse trend to leaf C:N ratios in the subtidal zone, but these tendencies were not observed in the intertidal zone. The effects of exposure appeared to cause no seasonal trend in eelgrass tissue C and N content or C:N ratios in the intertidal zone in the Seomjin Estuary.

• Journal of the korean society of oceanography
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• v.37 no.3
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• pp.108-115
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• 2002

To Investigate the distribution of resting eggs at the intertidal zone, Gomso Bay, samples were taken from the top of the sediments to 10 cm depth at four sites using a cylindrical corer in February, 1997. Additional samples were also taken from one station at subtidal zone to compare the distributions between the inter- and subtidal zones. The resting eggs of few copepods, Acartia pacifica, Centropages abdominalis, Calanopia thompsoni, and Tortanus forcipatus were studied. Mostly, the abundance of the resting eggs in the lower intertidal zone was greater than that in the upper intertidal zone, but was not significantly different from that in the subtidal zone. The abundance of the resting eggs in the intertidal sediments was related with the grain-size and moisture content of sediments. Intertidal sediments are potential egg banks like subtidal sediments.

• ALGAE
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• v.18 no.4
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• pp.301-309
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• 2003

Community structure and vertical distribution of benthic marine algae were investigated in the intertidal and subtidal rocky shore of Samyang, Jejudo Island. The total number of 62 algal species composed of 6 Cyanophyta, 6 Chlorophyta, 19 Phaeophyta, and 31 Rhodophyta were observed. The dominant species were melobesioidean algae, Sargassum thunbergii, Hizikia fusiformis, and Ulva pertusa in the intertidal zone and melobesioidean algae, Ulva pertusa, Corallina spp., and Undaria pinnatifida in the subtidal zone. The vertical algal distribution was represented by the melobesioidean algae in the whole rocky shore, Caulacanthus ustulatus in the upper intertidal zone, Sargassum thunbergii and Hizikia fusiformis in the middle and lower zone, Ulva pertusa in the lower zone and Ulva pertusa, Corallina spp., and Undaria prinnatifida in the subtidal zone. The composition of dominant species and pattern of the vertical distribution of algae in the present study were significantly different from the previous reports. Especially, distribution of crustose coralline algae was significantly extended.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.664-669
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• 2002

Intertidal zone (tidal flat) is a place which is sometimes dry and sometimes wet depending on the tidal rhythm. Direct measurement of topography in the intertidal zone is very difficult to be achieved. The interface between wet and dry parts in the tidal flat, which can be identified from near infrared band of satellite image, is a 'depth contour' which corresponds to the sea level at the time of satellite pass. Aquisition of topography data in tidal flat is possible by combining various techniques such as (1) identification of the interface between wet and dry parts, (2) GCP correction of satellite image, and (3) realtime prediction of sea level elevation at the time of satellite pass. The algorithm was successfully applied in obtaining topography (bathymetry) data in the intertidal zone of Asan Bay in the west coast of Korea from 26 satellite images. The method is expected to be very efficient in making bathymetry data base in the western and southern parts of Korea where tidal flats are well developed in wide regions.

• Journal of Environmental Science International
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• v.31 no.4
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• pp.357-363
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• 2022

In this study, we installed a weather observation tower tailored to the intertidal zone and established an intertidal weather observation system capable of real-time monitoring through a wireless network. This provided weather observation data representing the meteorological characteristics of the intertidal zone. To optimize this system in the future, we present practical directions for the development of observation equipment and for the data management and sharing, and we contribute to establishing the infrastructure.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.233-239
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• 2004

Microbial activity of biofilm formed on the surface of gravels from intertidal zone was estimated using an aerobic respirometer system, and compared with that of suspended marine microorganisms contained in a near shore water. The maximum oxygen uptake rate of the suspended marine microorganisms was 0.15mg O$_2$／L／hr, indicating the potential of purification of polluted near shore water. For the gravels from the intertidal zone, the maximum uptake rate of oxygen was affected by the vertical positions, but their gross value was 0.77mg O$_2$／L／hr, which was around 5.1 times higher than the purification potential of polluted near shore water by the microorganisms contained in the near shore water. The nitrogen removed by the gravels from the intertidal zone and the marine microorganisms was about 1／20-1／39 times of the total consumption of oxygen, which was similar to that of the phosphate. The gravel intertidal zone contained lots of particulate organics, over than that in the near shore water, and this was confirmed from the large difference between total oxygen consumption and the removed soluble COD in the microbial activity test. This indicates that the gravel intertidal zone plays an important role in controlling the non-point source pollutants from land, as well as self-purification of polluted near shore water by trapping and degrading the particulate organics.

• Journal of Navigation and Port Research
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• v.28 no.2
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• pp.155-159
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• 2004

Microbial activity of biofilm formed on the surface of gravels from intertidal zone was estimated using an aerobic respirometer system, and compared with that of suspended marine microorganisms contained in a near shore water, The maximum oxygen uptake rate of the suspended marine microorganisms was 0.15mg$O_2$/L/hr, indicating the potential of purification of polluted near shore water. For the gravels from the intertidal zone, the maximum uptake rate of oxygen was affected by the vertical positions, but their gross value was 0.77mg $O_2$/L/hr, which was around 5.1 times higher than the purification potential of polluted near shore water by the microorganisms contained in the near shore water. The nitrogen removed by the gravels from the intertidal zone and the marine microorganisms was about 1/20-1/39 times of the total consumption of oxygen, which was similar to that of the phosphate. The gravel intertidal zone contained lots of particulate organics, over than that in the near shore water, and this was confirmed from the large difference between total oxygen consumption and the removed soluble COD in the microbial activity test. This indicates that the gravel intertidal zone plays an important role in controlling the non-point source pollutants from land, as well as self-purification of polluted near shore water by trapping and degrading the particulate organics.

• Korean Journal of Environment and Ecology
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• v.21 no.6
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• pp.494-505
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• 2007

This study was carried out targeting the intertidal zone and estuary area of Anseo port in Saemangeum reclamation zone from 2003 to 2004, to analyze how reclamation affects the distribution of vegetation and soil properties. The plant growing in these survey areas was all halophytes: the vegetation on the intertidal zone consisted of simply 3 species of halophyte, and vegetation on the high tide zone and estuary area consisted of 9 and 8 species respectively, showing a more varied aspect than the intertidal zone. As for the plant species distribution, the predominant species for the intertidal zone were Suaeda maritima, Limonium tetragonum and Suaeda japonica; the predominant species for the slope zone of estuary were Suaeda maritima, Limonium tetragonum and Aster tripolium, and the predominant species for the inundation zone of estuary were Kochia scoparia var. littorea. At the analysis result of soil chemical properties, it was discovered that the appearance of the plant species was made at some spots on the intertidal zone whose electrical conductivity(EC), $Na^+,\;and\;Cl^-$ were relatively lower. EC of between the plant species was similar in the same zone, however EC was distinctively different between the same species in the different zone. Our study found out that whether the occurrence of the plant species is possible or not was decided by the difference in soil properties. This study results suggest that the distribution of vegetation is influenced by soil environment in that the appearance of the plant species on the intertidal zone and estuary area is differentiated by soil texture and soil chemical properties.

• Ocean and Polar Research
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• v.25 no.4
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• pp.519-528
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• 2003

Species composition and community structure of marine benthic community were studied in the intertidal zone of Jijindo Island, Gwangyang Bay. A total of 85 species of benthic marine plants including the 5 Cyanophyta, 9 Chlorophyta, 13 Phaeophyta, 56 Rhodophyta and 2 Magnoliophyta that were listed. The community structure was represented by Gelidium divaricatum in the upper zone, Celidium divalicatum and Ulva pertusa in the middle, and Ulva pertusa, Chondria crassicaulis, Chondracanthus intermedia and Sargassum thunbergii in the lower intertidal zone. The dominant species in the rnscro-zoobenthic community were Chthamalux challengeri in the upper and middle, Littorina brevicula between the upper and middle, and Mytilus edulis and Crassostrea gigas in the middle and lower intertidal zones. The economic benthic organisms such as Undaria pinnatifida, Mytilus edulis, and Crassostrea gigas found in the lower intertidal zone were frequently disturbed due to their collection by local resident. Therefore, it is necessary to record the correct information pertaining to these cases. The species diversity indices estimated kom different sources were quite different. They were 2.22 derived from frequency, 1.67 based on coverage, 2.17 based on sum of frequency and coverage and 2.04 derived from importance value. Species diversity and number of algal species in Gwangyang Bay have noticeably decreased, compared with their previously reported status. It is estimated that their decreases were caused by changes in the marine environment, especially pertaining to the polychaete community resulting from reclamation and dredging activity undertaken for the industrial development.