• Article

    Community Structure of Macrobenthic Polychaetes and its Health Status (Assessed by Two Biotic Indices) on the Adjacent Continental Shelf of Jeju Island, in Summer of 2020

    2020년 하계 제주도 인근 대륙붕 해역의 저서다모류군집 구조 및 저서생태계 건강도 평가

    Seo Yi Lee, Geon Kim, Ho Young Soh, and Hyun Chool Shin

    이서이, 김건, 서호영, 신현출

    This study was carried out to investigate the benthic polychaetous community and benthic ecosystem quality status on the adjacent continental shelf of … + READ MORE
    This study was carried out to investigate the benthic polychaetous community and benthic ecosystem quality status on the adjacent continental shelf of Jeju Island, and field surveys were conducted at 31 stations in July and August, 2020. The surface sediment was generally composed of muddy sand facies and sandy mud facies, and the average particle size was medium silt (6.1±1.6∅). The benthic polychaetous community revealed a total of 73 species with a mean density of 242 ind./m2. The major dominant species were Notomastus latericeus, Ampharete arctica and Onuphis shirikishinaiensis. By the cluster analysis and nMDS results based on species composition of the benthic polychaetous community, the study area was divided into three station groups arranged from east to west by the water depth and sedimentary facies. The station group located in the west was subdivided into two station groups from south to north. From results of correlation analysis and PCA, it was found that the benthic polychaetous community in the study area had a strong correlation with the sedimentary environment and water depth. The benthic faunal community (or ecosystem) on the adjacent continental shelf of Jeju Island was assessed to be in a healthy state by biotic indices such as AMBI and BPI. - COLLAPSE
    30 June 2022
  • Article

    Growth Rate and Annual Production of Halo-phyte (Suaeda japonica) on Tidal Mud-flat, Southern Part of Ganghwa-Isl, Korea

    강화 남부 조간대에 서식하는 칠면초(Suaeda japonica)의 연간 생장 및 생산 양상

    Ji-won Hwang, Kyun-Woo Lee, and Heung-sik Park

    황지원, 이균우, 박흥식

    This study examined the growth pattern and environmental factors affecting the growth of the halophyte, Suaeda japonica, which is prevalent on tidal … + READ MORE
    This study examined the growth pattern and environmental factors affecting the growth of the halophyte, Suaeda japonica, which is prevalent on tidal flats in the west coast of Korea in order to calculate annual carbon production. Quantitative sampling was conducted every month for three years from 2018 to 2020 on salt marshes located on the southern coast of Ganghwa Island. In terms of annual density affected by the germination rate at first period, especially when air temperature for winter time was constantly below 0°C for long periods of time, germination decreased and precipitation in summer also exerted an influence. In terms of annual growth with regard to length, the part below the ground grew rapidly in the beginning after budding, while the part above ground grew at a relatively steady rate at all times. With regard to biomass, the part below the ground also increased from April in a manner similar to length growth, but decreased drastically from September with leaves falling off and water loss occurring. The part above ground showed a rapid increase from the beginning of the rainy season. Size-frequency distribution revealed broader patterns after the rainy season as individual growth varied, but from September, it stopped at all year. High growth rates were recorded in the initial phase of growth after budding and growth was rapid, but growth declined in summer when biomass increased. The annual mean production based on growth rate was calculated at 352 gDWt/m2/yr, and the highest production was 519 gDWt/m2/yr in 2018, but it has decreased since 2019. Annual carbon production was at calculated 143.41 gC/m2/yr for Suaeda japonica in the vicinity of the southern coast of Ganghwa Island. - COLLAPSE
    30 June 2022
  • Article

    Mineralogical-geochemical Characteristics of Manganese Nodules in the Deep Subseafloor Sediments at Site U1371 in the Western South Pacific Gyre Area

    남서태평양 환류지역 U1371 심부퇴적층에서 발견된 망가니즈단괴의 광물학적-지화학적 특성 연구

    Kiho Yang and Jaewoo Jung

    양기호, 정재우

    Manganese nodules were recovered within the deep subseafloor sediments (118.22 mbsf) at Site U1371 during International Ocean Discovery Program (IODP) expedition 329 … + READ MORE
    Manganese nodules were recovered within the deep subseafloor sediments (118.22 mbsf) at Site U1371 during International Ocean Discovery Program (IODP) expedition 329 from the South Pacific Gyre (SPG). Because most manganese nodules exist on the seabed surface, nodules present in deep sediments are uncommon. Therefore, the growth origin of manganese nodules was identified through mineralogical and geochemical analyses. The manganese nodule was divided into the concentric layer outside the manganese region and the inner part of the phosphatized region consisting of manganese oxide minerals and carbonate fluorapatite (CFA) minerals, respectively. The two-dimensional element distribution analysis of Mn, Co, Ni, Sr and Cu, Zn with low Mn/Fe ratio confirmed that manganese nodules were formed predominantly by a hydrogenetic process and a biogenic process in certain manganese layers. As a result, the manganese nodule was continuously precipitated in SPG environments of oligotrophic open paleoocean conditions and rapidly buried with siliceous ooze sediments when the SPG changed to a eutrophic environment. It has been confirmed that manganese nodules found within deep subseafloor sediments could be used as a new proxy for the reconstruction of paleooceanographic conditions. - COLLAPSE
    30 June 2022
  • Article

    Legal Transformation of Advisory Procedure of the ITLOS into an Alternative Dispute Settlement Mechanism - From the Evaluation of Request for an Advisory Opinion Submitted by the Sub-Regional Fisheries Commission (Case No. 21), ITLOS

    분쟁해결을 위한 대체적 수단으로서 ITLOS 권고적 의견 절차 활용- SRFC 권고적 의견 사건(사건번호 21)을 중심으로 -

    Jee-hyun Choi

    최지현

    SRFC (Sub-Regional Fisheries Commission) requested to the ITLOS (International Tribunal for the Law of the Sea) an advisory opinion relating to the … + READ MORE
    SRFC (Sub-Regional Fisheries Commission) requested to the ITLOS (International Tribunal for the Law of the Sea) an advisory opinion relating to the IUU (Illegl, Unreported, and Unregulated) fishing (Case No-21 of the ITLOS). Since, in the UNCLOS, there is no article authorizing the jurisdiction of the ITLOS full court’s Advisory opinion, so various scholarly opinion wad divided. But ITLOS delivered its Advisory opinion confirming its jurisdictional competence over the Advisory proceedings with its legal opinion about the IUU issues. It opens new possibility of the alternative dispute settlement mechanism of the ITLOS through the advisory procedures. In reality, there has been a view that ICJ (International Court of Justice) could take the part of a kind of dispute settlement through its Advisory procedures. But the advisory procedures of the ITLOS, with no definite clause in UNCLOS about the advisory procedures, which provides more allowances for the function of advisory opinion as the alternative dispute settlement mechanism. ITLOS accepted the requests of the advisory opinion by the State parties through international organization or themselves directly. And the advisory opinion of the ITLOS aims the interpretation and application into the special issues-specially IUU fishing in Case No. 21 of the ITLOS-. Those factors could enable more enhanced role of the ITLOS as an alternative dispute settlement mechanism. But those possibility has contain risk of excessive and unlimited advisory role of the ITLOS. So it is important to focus on the restriction on the role of the State parties in the request of the advisory opinion to the ITLOS. In this regard it is meaningful that the ITLOS has suggested a kind of legal standing in the advisory procedures in that only coastal States could request the Advisory opinion about the IUU in their EEZ. Furthermore the discretionary power of the ITLOS in the Article 138 of the Rules of the Tribunal could curtail the abuse of the Advisory opinion initiated by the States parties of the UNCLOS. Under this framework, Advisory opinion could broaden more alternative option to the disputes between State parties of the UNCLOS in that after being delivered detailed interpretation of the UNCLOS about the specific issues, States parties could devote themselves to searching for flexible solution for the disputes between State parties. It could obtain legal explanation about the dispute under the Article 297 and Article 298 by detouring the jurisdiction limits through advisory procedures. - COLLAPSE
    30 June 2022
  • Review

    Status of Attachment Microalgae Taxa in the Korean Sea and Importance of their Research on Hull Ship Fouling

    해양의 부착 미세조류 분류군 현황 및 선체부착 연구의 중요성

    Jaeyeong Park, Taehee Kim, and Jang-Seu Ki

    박재영, 김태희, 기장서

    Microalgae can attach to the surface of ships and then spread to various areas by means of ship transport. The introduction of … + READ MORE
    Microalgae can attach to the surface of ships and then spread to various areas by means of ship transport. The introduction of invasive species through ships is recognized as a marine problem worldwide. Identification of attached microalgae is necessary to investigate such movement between countries through ships. In the present study, through analytical methods we reviewed research data to identify the taxa of domestic attached microalgae and assess the ecological impacts of such microalgae. A total of 87 genera and 153 species (143 species of diatoms, 10 species of cyanobacteria, and 4 genera of dinoflagellates) were identified as native attached microalgae in Korea, and diatoms accounted for 93% of the total. Most of these attached microalgae were identified through research on natural substrates such as seaweeds and bedrock, and some were also identified through experiments using artificial adherent plates. To date, there is no information on microalgae attached to international ships and introduced into Korea. Molecular genetic analysis and systematic management through on-site sampling of international ships, microscopic analysis, and meta-barcoding are necessary to assess the inflow and spread path of hull-attached marine alien species and evaluate the risk they pose to the domestic ecosystem. - COLLAPSE
    30 June 2022
  • Note

    Missing Pattern Analysis of the GOCI-I Optical Satellite Image Data
    Ho-Kun Jeon and Hong Yeon Cho
    Data missing in optical satellite images caused by natural variations have been a crucial barrier in observing the status of marine surfaces. … + READ MORE
    Data missing in optical satellite images caused by natural variations have been a crucial barrier in observing the status of marine surfaces. Although there have been many attempts to fill the gaps of non- observation, there is little research to analyze the ratio of missing grids to overall sea grids and their seasonal patterns. This report introduces the method of quantifying the distribution of missing points and then shows how the missing points have spatial correlation and seasonal trends. Both temporal and spatial integration methods are compared to assess the effectiveness of reducing missing data. The temporal integration shows more outstanding performance than the spatial integration. Moran’s I and K-function with statistical hypothesis testing show that missing grids are clustered and there is a non-random distribution from daily integration. The result of the seasonality test for Moran’s I through a periodogram shows dependency on full-year, half-year, and quarter-year periods respectively. These analysis results can be used to deduce appropriate integration periods with permissible estimation errors. - COLLAPSE
    30 June 2022