• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.11 no.3
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• pp.97-107
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• 2006

The nektonic assemblages of upper tidal flat area located in the Jangbong Island, near Incheon, were studied using a fence net from March to November 2001. A total of 49 species were recorded, with a mean abundance and biomass of 489 individuals and 5,170.4 g, respectively. The most abundant species by number were Exopalaemon carinicauda(40.9%) and Johnius grypotus(13.2%). By catch weight the dominant species were Acanthogobius hasta(33.7%), Johnius grypotus(14.6%) and Scomberomorus niphonius(10.2%). The conventional multivariate statistics(Cluster analysis and non-metric Multi-Dimensional Scaling) applied to assess temporal variation in nektonic communities. As a result of cluster analysis and MDS ordination, the faunal group could be divided into spring and summer/autumn dominant species group. The spring species included the pisces Acanthogobius luridus, the crab Macrophthalmus japonicus and the gastropods Bullacta exarata and Lunatia gilva. The summer/autumn species were the pisces J. grypotus, Sardinella zunasi, Konosirus punctatus, Chelon haematocheila, S. niphonius and Takifugu niphobles, the shrimp Metapenaeus joyneri and the cephalopod Loligo beka.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.3
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• pp.218-226
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• 2016

Field observations were used to study the characteristics and influence of groundwater level fluctuations on vegetation development on the natural beach of a sandy barrier island, in the Nakdong River estuary. The spatial/temporal fluctuations of the groundwater level and the interactions with the external forces (weather, ocean wave and tide) were analyzed. The results indicated that when it rains the groundwater level rises. During summer, when precipitation intensity is greater than 20 mm/hour, it rose rapidly over 20 cm. Subsequently, it fell gradually during periods of no precipitation. Seasonal characteristics indicated that the groundwater level was high during the summer rainy season and tended to fall in the winter dry season. The time-averaged groundwater level, observed from the four observations over 3 years (2012-2014), was about 1.47 m, higher than mean sea level (M.S.L.). It was shown that the average annual groundwater level rises toward the land rather than showing intertidal patterns observation. Differences in the presence or absence of a coastal sand dunes affected the progress of vegetation. In other words, in environments of saltwater intrusion where the groundwater level varies, dependent on the distance from the shoreline and bottom slope, sand dunes can be provided to affect soil conditions and groundwater, so that vegetation can be grown reliably.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.157-168
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• 2017

Backswamp is the section of a floodplain where deposits of fine silts and clays settle after a flood. In general, the wetland is composed of diverse ecosystems, and is characterized by ecotone. The purpose of this study was to analyze vegetation naturalness and to assess vegetation value by syntaxonomy and synecology of Useupje backswamp at Yeongsan river. As a result, the vegetation was divided into four physyiognomy types and 14 vegetation units depending on the species composition and habitats. The vegetation units confirmed in the study were as follow: Spirodela polyrhiza community as floating plant; Trapa bispinosa var. inuma community and Trapa bispinosa var. inumai-Nelumbo nucifera community as floating-leaved plant; Paspalum distichum community, Persicaria thunbergii community and Phalaridetum arundinaceae as lentic vegetation in the eulittoral zone; Scirpo fluviarilis-Zizanietum latifoliae and Typha angustata community in the emerged zone; Scirpetum tabernaemontani and Phragmitetum australis in the littoral zone; Carex dimorpholepis-Salix subfragilis community ecotone region of upland. According to the study, the vegetation distribution was highly affected by water level and artificial interference. Moreover, the development of vegetation units showed a significant relationship between species composition and habitats. Although vegetation value of Useupje resulted by vegetation naturalness was identified as the grade [III], the ecological value is expected to upward evaluation because of unique vegetation and geographical location.

• Journal of Wetlands Research
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• v.10 no.1
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• pp.49-57
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• 2008

Tidal flat, classified as wetland of coastal zone, is critical transitional zone connecting sea with land, and fulfills a variety of functions necessary for maintaining coastal ecosystem. Although it is critical to protect and strengthen its functions of coastal wetlands, tidal flat has been mainly viewed as areas for development in Korea. Therefore, this study provides with the effective mitigation measures so as to minimize adverse impacts of tidal flat reclamation projects on the proper environmental values. So far, coastal development has not considered as important the fact that development site consists of tidal flat in site selection. Therefore, large scale of tidal flats was abused. Problems were emerged only after tidal flat development was already planned. The original plan had to be revised. To rectify the problem, impacts of development on the environment need to be discussed based on the initial development planning. Particularly, sandy beaches, rocky shores and shallow areas, underwater forest including seagrass beds as well as the tidal flat in good condition should be excluded from development site.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.3
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• pp.177-184
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• 1987

The quantitative mechanics on the sideways walking of the crabs may provide a basic solution for entanglements of the walking legs in gillnets. The gaiting behaviour of the crabs on the flat board and the nettings 10, 16 and 23 mm in mesh size were experimented concerning about stepping positions and times in the laboratory using video set on July, 1984, It was found that the irregular movements of walking crabs in stepping positions and patterns were appeared on the nettings due to the absence of mechanical contact in spite of neural control of compensating, while on the flat surface evolved systematic leg movements. The mean stride length and walking velocity, which were increased with the carapace width on the flat board, as well as the step period and forward by backward stroke time were greater than those values on the netting, not associated with the carapace or the mesh size. Also, the step period and the Phase difference on the nettings revealed larger fluctuation than on the flat board. The joint angles of the walking legs, on the nettings in meropodite-carporodite and thorax-meropodite, which joint was varied especially up to below horizon because of the falling legs through the netting twine, were virtually wider than those on the flat substrate.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.9 no.1
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• pp.1-8
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• 1997

A horizontal 2-D model which includes the wetting-drying treatment technique in the intertidal zone is established for the prediction of tidal changes and contaminant transport due to the development of Incheon coastal zone. The flow model is verified by the measurement data at Jeong-Do, and then the computed values are closely matched to the observed water elevations and velocities of main-flow direction. And then, the tidal change patterns are simulated using this model before and after the construction of the Youngjongdo New Airport and Shihwa Seadike. In the spring tide condition, pollutants transport pattern is also simulated for the arbitrary pollutants loads. By the analysis of this numerical simulation results, the velocities after development are decreased, and discharged pollutants are mainly transported by the advection along a narrow deep trough. Thus, this model can be used as the compatible prediction model for the tidal change and pollutant transport due to the development plan of Incheon coastal zone.

• Animal Systematics, Evolution and Diversity
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• v.18 no.1
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• pp.35-48
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• 2002

Larval development of Chirona cristatus Ren and Riu, 1978, found in the low part of rocks in the intertidal clone or the shell of scallops, was described in detail and compared with those of other known barnacles. Durations from nauplius through cyprid to pinhead stage are three weeks at 20$\pm$0.5$^{\circ}C$. Trilobed labrum bearing three groups of slender hairs and frontolateral horns folded under the anterior cephalic shield margin are diagnostic features through all nauplius stages. The posterior border of the cephalic shield bears a pair of cephalic shield spines in nauplius stages IV,V and Ⅵ. There is no specific hispid sets at the fourth group of the antennal endpodite. The dorsal thoracic spine, abdominal process and posterior shield spine haute numerous small spines Morphological features such as the cephalic shield, labrum, abdominal process, antennules, antennae and mandibles in all nauplius and cyprid stages are illustrated and described. The numerical setations of antennule in this species are found to be practically helpful for intraspecific identification of barnacle nauplius stages without dissection.

• Journal of Korea Water Resources Association
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• v.35 no.4 s.129
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• pp.425-442
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• 2002

The land reclamation area of Saemangeum(Kunsan) is located between $126^{\circ}10'\;E{\sim}126^{\circ}50'\;E\;and\;35^{\circ}35'\;N{\sim}36^{\circ}05'\;N$ at the western coast of the Korean peninsula. The reclamation area of Saemangeum has a range of 5.6m spring tide and the maximum tidal current speed is about $1.41m\;s^{-1}$. In ordinary spring tide. Most of the sediments deposited on the tidal flats are transported from the Geum river, the Mankyung river and the Dongjin river. The soil in this area consists of silty sand with the depth of 10m to 30m. The wind in winter is strong from the direction of northwest. Saemangeum coastal area is being constructed 33km the sea dike and 40,100ha reclamation area. The purpose of this study Is to find the residual circulations in four seasons before and after the dike construction by a robust diagnostic and prognostic numerical model.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.4_2
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• pp.697-703
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• 2023

Intertidal zones, akin to tidal flats, are among the potential areas where underwater cultural heritage might be submerged. However, the shallow depths in these regions present challenges for conventional vessel-based survey methods. Moreover, during low tides, intertidal zones transform into tidal flats, limiting the efficiency of survey efforts due to restricted access and potential risks. As a result, proper underwater cultural heritage surveys encounter difficulties in these environments. In recent times, extensive research is underway to address these issues by investigating underwater cultural heritage surveys in intertidal zones, encompassing diverse fields, including equipment-based investigations. This study aimed to explore the feasibility of utilizing unmanned aerial vehicles (UAVs) to conduct intertidal cultural heritage surveys, employing aerial photography and 3D mapping to create detailed orthoimages and 3D models. The study focused on assessing the potential application of these techniques for cultural heritage surveying within intertidal zones. Notably, the survey conducted in Jindo's Naesan-ri demonstrated high-resolution capabilities, enabling the distinction of actual pottery fragments mixed within gravel fields. Similarly, in the survey of Jindo's Byeokpa-hang, it was found that a wooden pillar structure existed in a section about 200m long. The integration of various sensors, including LiDAR, with UAVs allows for diverse investigation possibilities, including bathymetric measurements, and is expected to facilitate the acquisition of varied datasets for further research and assessment.

• Korean Journal of Ichthyology
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• v.35 no.1
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• pp.44-49
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• 2023

A single specimen of the genus Bothus (family Bothidae) was collected for the first time at the intertidal zone of Moseulpo Port, Daejeong-eup, Seogwipo-si, Jejudo Island, on 14 August 2022. The specimen was identified as Bothus pantherinus in having following morphological traits: dark spots and ring-shaped patterns near eyes and the pectoral fins, one distinct spot in the center of the lateral line, 75 lateral line scales, and seven hourglass shaped supracranial pterygiophores. As a result of analyzing 603 bp of mitochondrial DNA COI sequences, our specimen was perfectly matched to those of B. pantherinus registered in NCBI. It has been known that the species is widely distributed throughout the Indo-Pacific Ocean from Red Sea to Hawaiian (32 degrees north to 32 degrees south), but this study revealed that its distribution expanded to the waters of Jejudo Island (33 degrees north), Korea. We propose its new Korean name "Beot-kkoch-mu-nui-dung-geul-neob-chi".