• Title/Summary/Keyword: Ulleungdo island

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Genetic diversity and distribution of edible scytosiphonacean algae from Ulleungdo Island, Korea

  • Lee, Ju Il;Jang, Hyeong Seok;Cho, Ga Youn;Yoon, Sung Jin;Boo, Sung Min
    • ALGAE
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    • v.34 no.3
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    • pp.229-236
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    • 2019
  • Despite the abundance of seaweeds from Ulleungdo Island, genetic diversity and distribution of edible brown algae from the island remain unstudied. We analyzed mitochondrial cox3 sequences from 86 specimens collected in the island and from the nearby Korean Peninsula. Our cox3 phylogeny for the first time confirmed the occurrence of fives species from Ulleungdo Island; Petalonia binghamiae, P. fascia, Planosiphon zosterifolius, and two cryptic species previously identified as Scytosiphon lomentaria. P. binghamiae was relatively homogeneous with three haplotypes. P. fascia comprised four haplotypes, which were grouped into two genetic lineages. S. lomentaria was heterogeneous with nine haplotypes and was divided into two cryptic species; one species clustered with taxa from cold waters while the other clustered with taxa from temperate and cold waters. Low genetic diversity in P. binghamiae while high genetic diversity in S. lomentaria from Ulleungdo Island are comparable to patterns observed from other species from the Korean peninsula. Ulleungdo Island, although small in size, is an ideal field laboratory to investigate genetic diversity and distributions of economic marine algae.

Study on the Annual Reproductive Cycle of the Comb Pen Shell, Atrina pectinata (Linnaeus, 1767) (Mollusca: Bivalvia: Pinnidae) on the Southern Coast of Ulleungdo Island, Korea (울릉도 남해역에 서식하는 키조개의 연중 번식주기에 관한 연구)

  • Yang, Hyun-Sung;Noh, Choong Hwan;Yoon, Sung Jin;Kim, Yun-Bae;Choi, Kwang-Sik;Kang, Do-Hyung
    • Ocean and Polar Research
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    • v.38 no.1
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    • pp.21-33
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    • 2016
  • Gametogenesis of the comb pen shell, Atrina pectinata (Linnaeus, 1767) (Bivalvia: Pinnidae) on the southern coast of Ulleungdo Island, Korea was assessed monthly (November 2013 to October 2014) using histology. Gametogenesis commenced in January when the surface water temperature was $12.6^{\circ}C$ and pen shells evidenced an early development phase with small oogonia from January to April, although few females exhibited ripe eggs in their follicular epithelium. In April, the oocyte diameter increased rapidly, and fully mature eggs appeared in May. First spawning males and females were observed in June as the surface water temperature reached $19.3^{\circ}C$ and July ($23.2^{\circ}C$) respectively. The spawning activity continued until the end of September. Histology indicated that the spawning peak of the females in Ulleungdo Island was July to August. During October to January, most of the pen shells were in spent and resting stages. Our data suggested that A. pectinata is a summer spawner, and their annual gametogenesis is closely associated with the seasonal variation in the surface water temperature. The present study is the first provided fundamental information on the life history of A. pectinata in Ulleungdo Island, and this can be put to good use in the management of this pen shell in the study area.

A new species of Epilobium (Onagraceae) from Ulleungdo Island, Korea, Epilobium ulleungensis (한국(울릉도)의 1신종: 울릉바늘꽃)

  • Chung, Jae-Min;Shin, Jae-Kwon;Sun, Eun-Mi;Kim, Hoe-Won
    • Korean Journal of Plant Taxonomy
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    • v.47 no.2
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    • pp.100-105
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    • 2017
  • A new species, Epilobium ulleungensis J. M. Chung (Onagraceae Juss), from Ulleungdo Island (South Korea) was described and illustrated. Among four taxa native to Ulleungdo Island (E. amurense Hausskn. subsp. cephalostigma (Hausskn.) C. J. Chen, Hock & P. H. Raven, E. hirsutum L., E. pyrricholophum Franch. Sav., and E. ulleungensis), E. ulleungensis has a unique tetragonal stigma, which is considered to be an intermediate form between clavate (E. pyrricholophum) or capitate (E. amurense subsp. cephalostigma) and 4-lobed stigmas (E. hirsutum). More importantly, this new species is clearly distinguished from the other three taxa distributed on Ulleungdo Island by its height (over 200 cm), decumbent stem, leaf shape, short, dense pubescent covering on the whole plant, large flower size, and a dark pink or red purple flower. According to the stigma shape and other characters, it was estimated that E. ulleungensis is a hybrid between E. hirsutum and E. pyrricholophum or E. amurense subsp. cephalostigma). The specific epithet "ulleungensis" was chosen because the new species was restricted to Ulleungdo Island.

High-Resolution Flow Simulations Around a Steep Mountainous Island in Korea Using a CFD Model with One-way Nested Grid System

  • Mun, Da-Som;Kim, Jae-Jin
    • Korean Journal of Remote Sensing
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    • v.36 no.4
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    • pp.557-571
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    • 2020
  • High-resolution flows around a steep mountainous island (Ulleungdo) in Korea were simulated by a computational fluid dynamics (CFD) model. To cover entire Ulleungdo and to resolve the topography around the Ulleungdo automatic synoptic observing system (ASOS) with high resolution, one-way nested grid system with large (60 m), and small (20 m) grid sizes was applied in the CFD model simulations. We conducted the numerical simulations for 16 inflow directions, and, for each inflow direction, we considered six different wind velocities(5, 10, 15, 20, 25, and 30 m s-1) at the reference height (1,000 m). The effects of topography on surface wind observations were well reflected in the observed wind roses for the period of January 01, 2012 ~ December 31, 2016 at the Ulleungdo ASOS and marine buoy. Wind roses at the Ulleungdo ASOS was reproduced based on the CFD simulations. The changes in surface winds at the Ulleungdo ASOS caused by surrounding topography were relatively well simulated by the CFD model. The simulated wind-rose indicated that south-southwesterly and northeasterly were the dominant wind directions, which were also observed at the Ulleungdo ASOS. We investigated the flow characteristics around the Ulleungdo ASOS for northwesterly, south-southwesterly, and northeasterly winds in detail.

Study on Species Identification Error Caused by Comparing Feces Appearance of Felis catus and Prionailurus bengalensis in the Ecosystems

  • Lee, Yoon Jeong;Kim, Jong Hyun;Kim, Eui Kyeong
    • Journal of Forest and Environmental Science
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    • v.37 no.4
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    • pp.331-337
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    • 2021
  • This study is designed according to the fact that the feces presumed to be from a Prionailurus bengalensis was found in Ulleungdo Island, where Prionailurus bengalensis is not known to inhabit, and that visual observation of the feces may cause errors in species identification. The feces observed in Ulleungdo Island on October 21, 2019 and August 29, 2020, in Gyeongju on December 4, 2020, and in Jecheon on December 7, 2020 was found intactly on grass, not buried in the ground. Although it was difficult to distinguish and identify the feces of Felis catus and Prionailurus bengalensis with visual observation, the feces collected from Ulleungdo Island was closely related to the Felis catus according to the genetic analysis whereas the ones collected from Gyeongju and Jecheon was identified from Prionailurus bengalensis. Therefore through the gene analysis, this study proved that visual observation of feces with similar appearance, specifically the feces found in Ulleungdo Island, Gyeongju, and Jecheon, may cause errors in species identification. It is judged to be necessary to analyze fields signs and genes for the species identification when using the feces of Felis catus and Prionailurus bengalensis.

Social Wasp Diversity and Wasp Nest Removal Trends on Ulleungdo Island, South Korea

  • Jaehee Kim;Il-Kwon Kim;Ohseok Kwon;Moon Bo Choi
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.4 no.4
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    • pp.146-153
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    • 2023
  • This study aimed to conduct a comprehensive survey of social wasp diversity and its impacts on remote Ulleungdo Island, South Korea. A total of 12 wasp traps were placed across the island, and specimens were collected monthly from May to October. Additional collection was conducted by thoroughly inspecting the areas surrounding the traps. The traps yielded a total of 5,068 individuals, representing two genera and two species. A total of 3,961 Vespa simillima simillima Smith individuals (78.2%) were collected, and 1,107 individuals (21.8%) were identified as Vespula flaviceps flaviceps Smith. Additionally, five individuals of Polistes snelleni de Saussure were collected through sweeping, bringing the total to 5,132 individuals of three genera and three species. It is worth noting that our findings indicate potential misidentifications in the species list of Vespidae found in the literature. Emergency services call centers reported the removal of 60 social wasp nests on Ulleungdo Island between 2018 and 2022, with the highest number of reports occurring from July to September, accounting for 87% of all cases. Dodong-ri and Jeodong-ri, with the highest populations, reported the most incidents, although fortunately, there have been no recent injuries. Past incidents involving the destruction of dried squid products by Vespula species have resulted in significant economic losses, underscoring the need for preventative measures. Furthermore, ongoing surveillance of hornet invasions is essential to safeguard the Jangwon bees being reared on Ulleungdo Island.

A Taxonomic Study on Marine Sponges from Ulleungdo Island, Korea (울릉도 해산 해면류의 분류학적 연구)

  • Sim Chung Ja;Kang Dong Won
    • Animal Systematics, Evolution and Diversity
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    • v.20 no.2
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    • pp.161-170
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    • 2004
  • A taxonomic study on the marine sponges was conducted with material collected by SCUBA diving from Ulleungdo Island, Korea during July 2001 to August 2003. They were identified 19 species belonging to 14 genera in 12 families of six orders in two classes identified. Among them, Haliclona (Reniera) permollisimilis Hoshino, 1981 is newly recorded to the Korean fauna and Geodia ulleungensis n. sp. is new to science.

Tofieldia ulleungensis (Tofieldiaceae): A new species, endemic to Ulleungdo Island, Korea

  • JO, Hyeryun;GHIMIRE, Balkrishna;HA, Young-Ho;LEE, Kang-Hyup;SON, Dong Chan
    • Korean Journal of Plant Taxonomy
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    • v.50 no.3
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    • pp.343-350
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    • 2020
  • Tofieldia ulleungensis, a new species of the genus Tofieldia from the Nari Basin on Ulleungdo Island, Korea, is described and illustrated. The new species is similar to T. yoshiiana var. koreana in terms of the plant height and in that it has having a long raceme, whitish tepals, and whitish stigma, but can be readily distinguished from the latter by the presence of 1-2 linear cauline leaves, a slightly bent leaf apex, basal leaves which are twice as wide, a shorter pedicel, a revolute style, and crescent-shaped seeds.

Two New Species of the Genus Mycale (Naviculina)(Poecilosclerida: Mycalidae) from Ulleungdo Island, Korea

  • Sim, Chung Ja;Kang, Dong Won
    • Animal cells and systems
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    • v.8 no.2
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    • pp.71-75
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    • 2004
  • A study on marine sponges was conducted by SCUBA diving at Ulleungdo Island, Korea, from July 2001 to August 2003. Two species, Mycale (Naviculina) ulleugensis and Mycale (N.) neunggulensis, are new to science. Mycale (N.) ulleugensis n. sp. seems close to M. chungae based on the shape of spicules, but differs in the size of megascleres and sigmas, Mycale (N.) neunggulensis n. sp. seems close to M. flagellifer Vacelet and Vasseur in the type and size of spicules, but differs in the shape of naviculichela. Naviculichela I of M. flagellifer has a spine on the upper part of the felix.

Allium ulleungense (Amaryllidaceae), a new species endemic to Ulleungdo Island, Korea

  • CHOI, Hyeok-Jae;YANG, Sungyu;YANG, Jong-Cheol;FRIESEN, Nikolai
    • Korean Journal of Plant Taxonomy
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    • v.49 no.4
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    • pp.294-299
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    • 2019
  • Allium ulleungense (subg. Anguinum, Amaryllidaceae), from Ulleungdo Island, Korea, is described as a new species. It is clearly distinguished from its close relatives, A. microdictyon and A. ochotense, by its broader leaves and larger whitish perianth and by its diploid chromosome number, which is 2n = 2x = 16. The lengths of the chromosomes range from 11.3 to 15.75 ㎛. Molecular phylogenetic analyses using nuclear and chloroplast markers also clearly indicate that A. ulleungense is genetically distinct from other species of the subg. Anguinum.