• 한국해양학회지
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• v.15 no.1
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• pp.8-16
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• 1980

The seed of Japaness oyster, Crassostrea gigas(Thunberg), cultivated along the southerncoast of Korea have been transplanted and cultivated in both the Seonyu island and the Eocheong island of the western coast of Korea. The present study was carried out to investigate the growth of transplanted oysters, environmental factors influencing their fatness, and differences of two areas between the Seonyu island and the Eocheong island during the period from April to November, 1978. The results obtained were as follows: 1. Maximum height of the shell was 69.2mm (58.4mm on the average) in the island of Seonyu and 64.8mm(53.2mm) in the island of Eocheong, respectively. 2. The fatness of the oysters measured in the island of Seonyu (5.2g/month) was greater than in the island of Eocheong (2.5g/month) 3. The shell height was increased with high temperature while, the shell fatness with low temperature. 4. The growth rate of the transplanted seed oysters was twice as much as that of native ones in the western coast of Korea. 5. Environmental conditions of Seonyu island were more favorable in cultivating oysters than those of the Eocheong island.

• Ocean and Polar Research
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• v.35 no.4
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• pp.281-290
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• 2013

The vertical structure of sediment temperatures in the tidal flats of Geunso Bay and Seonyu Island in western Korea were measured for more than a year and analyzed. Mean temperature decreased with depth in spring and summer. On the contrary, it increased with depth in fall and winter, faithfully reflecting the seasonal variation resulting from the heating and cooling of the surface sediment. The surface sediment temperatures are shown to be strongly dependent on solar radiation, M2, and M4 tidal components. They are also weakly affected by precipitation. Thermal diffusivity of sediment is estimated at each depth and in each of the four seasons by applying the amplitude equation method. In Geunso Bay, the estimated seasonal-mean values decreased with depth, while they showed little change in Seonyu Island. Depth-averaged thermal diffusivity in Geunso Bay ($1.94 {\times}10^{-7}m^2/s$) was smaller than Seonyu Island ($2.20 {\times}10^{-7}m^2/s$). The variability of thermal diffusivity is shown to corelate with sediment composition and sorting from the grain-size analysis of intertidal sediments in Geunso Bay and Seonyu-do.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.4
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• pp.32-50
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• 2019

The present study examines the circumstances around the establishment of the Seonyu Eight Scenic Spots (仙遊八景) in Gogunsan Islands and the characteristics of the landscape of each viewing point. The study conclusions are as follows. First, since the scenic spots were first established in 1969, their content and sequences have been changed several times, and their names have also been changed to some extent. Until the 1970s, these scenic spots did not have official names for them and were often specified as 'Gogunsan Eight Scenic Spots', and excluded 'the Musan Twelve Peaks (巫山十二峰)'. In addition, viewing points of the eight scenic spots varied across periods. This suggests that, for the early form of Seonyu Eight Scenic Spots, the picturesque scenery of Gogunsan Islands, and Seonyudo Island in particular, was chosen, while eight scenic spots in its vicinity were regarded. Second, the Seonyu Eight Scenic Spots of the early 2000s, which has all eight scenic spots of now, follows the nomenclature of the traditional eight scenic spots by specifying the sequence number with a refined name in four syllables. Its first scenic spot was Mangju Waterfall (望主瀑布) and its eighth scenic spot was Seonyu Sunset (仙遊落照); currently, the first scenic spot is Seonyu Sunset and the second scenic spot is Mangju Waterfall. Such change in the sequence of viewing points resulted from differences in representative landscape resources between the periods. Third, the lack of structure and finesse due to continuous changes is directed related to the identity issue of the Seonyu Eight Scenic Spots. Above all, it is unclear by whom and when Seonyu Eight Scenic Spots was established, and there are clear traces of following the eight scenic spots in the neighboring areas such as Okgu (沃溝) and Impi (臨陂)'s Eight Scenic Spots. Moreover, it is evaluated to have an unrefined, incomplete structure due to the lack of clarity in the knowledge and information about viewing objects, when to view, and historical and cultural background. Fourth, the first scenic spot, Seonyu Sunset, has the image that dominates the entire Eight Scenic Spots. The temporary landscape, the sunset, became the best view because it was perceived as the entirety of the landscape created by the fusion of the beautiful natural elements of Seonyudo Island. Therefore, there is ample room for raising the value of other landscape resources of Gogunsan Islands by utilizing the existing perception of exploring the entire landscape of Seonyudo Island and Gogunsan Islands starting with Seonyu Sunset. This likely requires additional work to imbue each viewing point with identity and completion.

• Korean Journal of Ichthyology
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• v.36 no.2
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• pp.164-173
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• 2024

We collected fish from the intertidal zone of Seonyu-do Island in order to find out the composition of fish species by using hand net and kick net from March to October 2022. During the investigation period, a total of 2,707 individuals from 9 Orders, 19 Families, 45 Species were collected, and the dominant species was identified as Nuchequula nuchalis and the subdominant species was Favonigobius gymnauchen. By family group, the largest number of fishes in the Gobiidae were 13 species, followed by the Scorpaenidae and the Stichaeidae were 4 species. In this study, genus Clariger was discovered for the first time off the West sea, and it is estimated that fish living on the southern coast are moving northward due to an increase in the water temperature of the West Sea and detailed research is needed.

• The Journal of the Petrological Society of Korea
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• v.28 no.4
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• pp.251-277
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• 2019

The Gogunsan Archipelago is composed of two island groups; the first group includes Mal-do, Myeong-do, Gwangdae-do, and Bangchuk-do islands consisting of Neoproterozoic rocks, and the second group includes Yami-do, Sinsi-do, Muneo-do, Jangja-do, and Seonyu-do islands consisting of Cretaceous rocks. The first group mainly consists of the Bangchuk formation which can be divided into two layers; the lower layer was more deformed than the upper layer. The former was intruded by mafic and felsic volcanic rocks formed in the volcanic arc tectonic setting 930-890 Ma and the latter was deposited ca. 825-800 Ma. In these islands, large scale folds with east-west fold axes were beautifully formed; the Maldo island fold was designated as natural monument and large scale beautiful chevron fold was developed on the Gwangdae-do island. In addition, there are unique zebra-shaped outcrop formed by a mixing of basic and acidic magma and Independent Gate shaped outcrop formed by coastal erosion. On the other hand, the Yami-do, Sinsi-do, Muneo-do, Jangja-do and Seonyu-do islands consist of 92-91Ma Cretaceous volcanic rocks and, in Sinsi-do island, the Nanshan formation deposited ca. 92 Ma. These Cretaceous volcanic rocks formed by melting of the continental crust by the heat supplied from the uplifting mantle due to the extension caused by a retreat of subducting ocean slab. Yami-do and Sinsi-do islands are composed of rhyolite. In Yami-do island, bands with vertical joint formed by cooling of the bottom part of the lava, are shown. In Sinsi-do island, large-scale vertical joints formed by cooling of lava flow, were developed. The Jangja-bong of Jangja-do island and Mangju-bong of Seonyu-do island are composed of brecciated rhyolite and formed a ring shaped archipelago contributing to the development of marine culture by providing natural harbor condition. They also provide beautiful views including 'Seonyu 8 views' along with other islands. As mentioned above, the Gogunsan archipelago is rich in geoheritages and associated cultural and historical resources, making it worth as a National Geopark.

• Journal of Species Research
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• v.8 no.1
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• pp.136-159
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• 2019

This study was carried out to investigate the flora of six islands belonging to the Gogunsan Archipelago (i.e., Sinsi-do, Seonyu-do, Munyeo-do, Yami-do, Bian-do, and Duri-do) in the Korean Peninsula. As results of five field surveys from March to October of 2016, we have identified 575 total taxa, representing 527 species, five subspecies, 42 varieties, and one hybrid, placed in 358 genera and 118 families. Of these 575 taxa, four are endemic to Korea, six taxa are listed on the Korean Red List of threatened species, 67 are floristic regional indicator plants, and 74 are invasive alien species. In this study, we compared species richness among the islands, and find that the larger the islands, the higher the species richness. In the case of habitat affinity types, forest species were most common, followed by farmland, seacoast, bare ground and wetland species. From similarity analyses based on the composition of vascular plants, each island did not exhibit either local specificity or unique diversity. On the contrary, the proportion of invasive alien and ruderal species may increase by human activities. Investigations and analyses of island flora such as this are important to assess the current status of the flora, predict future vegetation patterns and the spread of the alien species, and establish managment plans of plant diversity.