• 제목/요약/키워드: Archipelago

검색결과 101건 처리시간 0.024초

Biak and Wakatobi reefs are the two hottest hotspots of coral reef fish diversity and abundance in the Indonesian Archipelago

  • Imam Bachtiar;Edwin Jefri;Muhammad Abrar;Tri Aryono Hadi
    • Fisheries and Aquatic Sciences
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    • 제25권11호
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    • pp.549-558
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    • 2022
  • The Indonesian Archipelago has a very complex geological history, along with equatorial warm sea temperature, resulting in diverse types of coral reefs and high diversity of coral reef fish. Many livelihoods of the coastal community are dependent on coral reef fisheries. The present study aimed to determine which region and location in the Indonesian Archipelago has the most diverse and abundant coral reef fish. The archipelago was divided into four regions: the Indian Ocean, Sunda Shelf, Wallacea, and the Pacific Ocean. Data were obtained from a national coral reef monitoring program of the Indonesian Research Center for Oceanography (RCO)-the National Board for Research and Innovation (BRIN). The reef fish data were collected using the underwater visual census method, from 321 belt transects on 24 locations (districts) across the archipelago. The results show that coral reef fish diversity of the Pacific region was the highest across the archipelago for all three trophic levels, i.e., corallivore, herbivore, and carnivore fish. The Pacific Ocean region also had the highest fish abundance for the three trophic levels. Comparison among locations revealed that the best ten locations in reef fish diversity and abundance were Sabang, Mentawai, Makassar, Selayar, Buton, Luwuk, Ternate, Raja Ampat, Biak, and Wakatobi. Wakatobi reefs showed their supremacy in carnivore fish diversity and abundance, while Biak reefs were the best in herbivore fish. The abundance of corallivore fish was also considerably high in Sabang reefs, but it is still lower than in Raja Ampat, Biak, and Wakatobi reefs. These results provide empirical evidence that the coral reefs of Wakatobi and Biak are the hottest hotspots of coral reef fish diversity and abundance in the Indonesian Archipelago.

고군산군도 내측해역의 현생퇴적환경 (Modern Sedimentary Environments Within the Gogunsan Archipelago)

  • 이희준;김민지;김태경
    • Ocean and Polar Research
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    • 제30권4호
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    • pp.519-536
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    • 2008
  • The relatively tranquil area within the Gogunsan Archipelago was for the first time investigated preliminarily with respect to modern sedimentological processes in association with the emplacement of the Saemangeum Dyke. Basic sedimentological observations, bathymetry and surface sediments were performed twice during 2006-2008 to compare the results and elaborate changes during that period of time. In addition, sediment dynamical observations were carried out with latest measuring equipment along two transects crossing the entrances of the archipelago, including 12-hour onboard measurements of current, suspended sediments, temperature, and salinity. This dataset was used to reveal hydrodynamic characteristics for spring season April-May and to estimate the direction and relative magnitude of the net flux of suspended sediments. There occurred three depositional areas (A to C) within the archipelago, where sediment texture was also changed. In area A, around Yami Island and the dyke, and area B, in the center of the archipelago, surface sediments became coarsened over the two-year period; sand content increased 5% at the expense of silt content in the former, whereas silt content increased 3% at the expense of clay content in the latter. By comparison, area C in the western entrance of the archipelago shows a textural trend of fining with more silt and clay (combined increase of 5%) at the expense of sand content. The accumulation of sediments in areas A and B is attributable to the sand and silt resuspended from the seabed sediments off sector 4 of the dyke during the winter. The origin of the fine materials depositing on area C is uncertain at present, although suspended sediments moving offshore around the archipelago may be one of the most likely candidates for the source. The temperature of seawater increased rapidly from $9-10^{\circ}C$ in April to $14-16^{\circ}C$ in May, whereas salinity remained more or less constant at 31-32%o during the two months. Both of these parameters showed little variations with depth through a tidal cycle, suggesting good mixing of seawater without any help of significant waves. The consistency of salinity during a tidal cycle also indicates no insignificant effects of freshwater from the rivers Mangyung and Donjin emitting through the opening gap near Sinsi Island. The suspended sediment concentrations were higher at the entrance between Sunyu and Sinsi islands than at the entrance between Hoenggyong and Sinsi islands, ranging from 20 and 30 mg/l and from 5 and 15 mg/l, respectively at the sea surface. Although tidal currents were variable across a transect between Sunyu and Sinsi islands, the currents across the entrance between Hoenggyong and Sinsi islands flowed consistently in the same direction all over the transect during a tidal cycle. The estimation of net flux of suspended sediments indicates that suspended sediments are transferred to the Gogunsan Archipelago mainly through a relatively deep trough adjacent to Sinsi Island toward the shallow area around Yami Island and the dyke.

서남권 다도해 해역의 해양레저 기반여건분석 (Analysis of Marine Leisure base condition for the Archipelago at the Southwest Sea Area)

  • 박성현
    • 한국항해항만학회지
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    • 제30권3호
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    • pp.253-258
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    • 2006
  • 본 논문에서는 해양레저를 즐길 수 있는 천혜의 자연조건을 가진 서남권 다도해 해역의 해양레저 기반여건 분석에 관하여 논의한다. 먼저 국내 해양 레저와 요트 산업의 현황과 문제점에 대하여 분석하고 개선 방안을 제시한다. 특히 환경 친화형의 마리나 시설을 서남권 다도해 해역에 적용하여 그 타당성을 분석한다.

Marine macroalgae and associated flowering plants from the Keret Archipelago, White Sea, Russia

  • Garbary, David J.;Tarakhovskaya, Elena R.
    • ALGAE
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    • 제28권3호
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    • pp.267-280
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    • 2013
  • The marine algal flora of the Keret Archipelago ($66^{\circ}$ N, $33^{\circ}$ E) in the White Sea, Russia was investigated during 2008. Over 250 algal records from more than 15 islands and several sites on the adjoining mainland produced a total of 62 algal species. This raised the total from 56 to 88 species of Chlorophyta (23 species), Phaeophyceae (31 species), Rhodophyta (33 species), and Tribophyceae (1 species) of which seven were new records or verifications of ambiguous records for the White Sea and 11 species are new for the Keret Archipelago. The new or confirmed records included species of Blidingia, Eugomontia, Prasiola, Rosenvingiella, and Ulothrix (Chlorophyta), Acrochaetium, Colaconema (Rhodophyta), and Vaucheria (Tribophyceae). Five species of flowering plants (Aster, Plantago, Triglochin, and Zostera) were associated with the macrophytic algal vegetation of the region. Five fucoid algae in Pelvetia, Fucus, and Ascophyllum provide a picture of a temperate flora. Regardless, the overall species richness is consistent with an arctic nature to the flora. This discrepancy is attributed to the 'filter' provided by the Barents Sea of the Arctic Ocean for post-glacial colonization of the White Sea.

Analysis of Seven Islands with Insect Fauna and Vascular Plant Flora in Gogunsan Archipelago, Korea

  • Hwang, Jeong Ho;Yim, Mean-Young;An, Seung-Lak;Paek, Woon-Kee;Lee, Wang-Hee
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • 제3권1호
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    • pp.23-31
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    • 2022
  • The analysis of seven islands in Gogunsan archipelago, Korea with insect fauna and vascular plant flora was carried out based on a field survey conducted in May, July, and September. As a result, a total of 2,817 insect individuals including 264 species and 315 taxa of vascular plant were recorded. Bangchukdo the largest island among the seven islands showed the largest number both insect species and plant taxa. The similarity analysis suggested that the nearness of each island strongly affected the insect fauna and vascular plant flora on each island. In addition, there was significant correlation between the areas of each island and the numbers of insect species (Spearman's correlation coefficient=0.857, P-value=0.014). In the future, the results of this study can be used as data related to island ecology and conservation.

한국 서남해 압해도 주변 다도해역의 조류 및 조석잔차류 분포 (Characteristics of Tidal Current and Tidal Residual Current in the Archipelago Around Aphae Island in the Southwestern Waters of Korea)

  • 추효상;김동선
    • 해양환경안전학회지
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    • 제24권2호
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    • pp.179-187
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    • 2018
  • 수치모델실험을 사용하여 한국 서남해 압해도 주변 해역의 조류 및 조석잔차류 분포를 파악하였다. 조류는 대체로 반 일주조가 탁월하며, 조류 주방향은 압해도 주변 다도해역이 좁은 협수로인 관계로 대부분 수로를 따라 형성되었다. 조류타원 형태는 주변수심 및 인근에 산재한 섬 주위 해저지형의 영향으로 대부분 직선에 가까운 왕복성이었으나, 매화도~증도 사이 기점도, 화도, 당사도 주위에 약한 회전성 조류타원 형태였다. 창조류는 화원반도 서쪽 연안을 따라 팔금도~암태도, 암태도~증도 수로에서 북동류한 조류와 함께 압해도 북서쪽 다도해로 빠지고, 낙조류는 반대로 북서 다도해의 협수로를 따라 암태도~증도, 암태도~팔금도를 통과하고 암태도~증도에서의 조류는 팔금도~화원반도 서쪽 연안을 따라 남류했다. 압해도 연안은 창조시 북류한 흐름이 해안에서 동서로 분류되어 압해도 서쪽과 동쪽을 따라 흐르고 낙조시는 조간대 만곡부에서 남류한 흐름과 섬 서쪽과 동쪽에서 남~남동류한 흐름이 팔금도~화원반도 사이로 흘렀다. 조류유속이 강한 곳은 암태도~압해도 사이 합류역이었다. 조석잔차류는 다도해 협수로의 빠른 유속으로 섬 주변 흐름 하류역에 후류와 또는 지형성와류가 형성되었다. 압해도 서쪽에 약한 반시계방향 와류와 압해도 북서 만곡부에 시계방향 환류가 존재했다. 북쪽 협수로를 제외한 압해도 연안은 조간대가 발달되어 조석잔차류 유속이 미약하였다.

多島海 海上國立公園內의 常綠闊葉樹林에 對한 植物社會學的 硏究 ( II ) - 金鰲列島의 植生을 中心으로 - (Phytosociological Study on the Evergreen Broad-leaved Forests in Dadohae National Marine Park -The vegetation of Kumo Archipelago-)

  • Kim, Chul-Soo;Oh, Jang-Geun
    • The Korean Journal of Ecology
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    • 제13권4호
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    • pp.343-359
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    • 1990
  • Phytosociological investigation of the forest vegeation was carried out in Kumo archipelago at the period of May 21th 1990 to May 29th 1990 by Braun-Blanquet's method. The forest vegetation was classified into 7 communities, Camellia japonica, Castanopsis cuspidata var. sieboldii, Machilus thunbergii, Camellia japonica-Pinus thunbergii, Camellia japonica-Torreya nucifera, Carpinus coreana and Quercus acutissima community. Based on the classification of communities, the actual vegetation maps were drawn in 1 : 50,000 scale.

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서남권 다도해 해역의 해양 레저와 요트 산업 적용 (A marine leisure of the archipelago at the southwest sea area and its adaptation to yacht business)

  • 박성현;정대득;정중식;김철승;남택근
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2004년도 추계학술대회
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    • pp.197-202
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    • 2004
  • 본 논문에서는 해양레저를 즐길 수 있는 천혜의 자연조건을 가진 서남권 다도해 해역의 해양레저와 요트 산업 적용에 관하여 논의한다 먼저 해양레저의 해외 우수 사례를 소개한다. 아울러 국내 해양 레저와 요트 산업의 현황과 문제점에 대하여 분석하여 개선 방안을 제시하고자 한다. 특히 환경 친화형의 마리나 시설을 서남권 다도해 해역에 적용하여 그 타당성을 분석한다. 향후 해양레저 산업의 전망을 분석한다.

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Intraspecific Molecular Phylogeny, Genetic Variation and Phylogeography of Reticulitermes speratus (Isoptera:Rhinotermitidae)

  • Park, Yung Chul;Kitade, Osamu;Schwarz, Michael;Kim, Joo Pil;Kim, Won
    • Molecules and Cells
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    • 제21권1호
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    • pp.89-103
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    • 2006
  • Population structure was investigated in Reticulitermes speratus populations in the Korean Peninsula and the Japanese Archipelago. All trees derived from analyses of the combined sequence dataset of two mitochondrial genes, COII and COIII, showed that R. speratus populations cluster into two major clades comprising the Korean/southern Japanese populations and the northern Japanese populations. Analysis of population genetic structure showed strong genetic partitioning between populations of the two clades. To understand historical migration routes and current distributions, the phylogeographic history of R. speratus was inferred from intra-/interspecific phylogeny and divergence times estimated between the clades of the phylogenetic tree. The estimated migration route and divergence time of ancestral R. speratus are congruent with recent paleogeographic hypotheses involving land-bridge connections between the Asian continent and the Japanese Archipelago. We suggest that ancestral R. speratus separated into northern and southern Japanese populations after its migration into the Japanese main islands from East China during the early Pleistocene via the East China Sea basin, which may have been exposed during that period. The Korean populations seem to have diverged recently from southern Japanese populations; this may explain the current distribution of R. speratus in the Japanese Arachipelago, and account for why it is restricted to northern areas of the Tokara Strait.

多島海 海上國立公園內의 常綠闊葉樹林에 對한 植物社會學的 硏究 - 鳥島群島의 植生을 中心으로 - (Phytosociological Study on the Evergreen Broad-Leaved Forest in Dadohae National Marine Park -The Vegetation of Chodo Archipelago-)

  • Kim, Chul-Soo;Oh, Jang-Geun
    • The Korean Journal of Ecology
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    • 제13권3호
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    • pp.181-190
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    • 1990
  • Chodo Archipelago ($125^{\circ}$45 $-126^{\circ}$13 E and $34^{\circ}$15 $-34^{\circ}$25 N, ca. $56.7km^2$), a part of the Dadohae National Marine Park, largely is covered with substitutional vegetation under various human impact such as grazing, cutting for firewood. However natural vegetation is partially distributed in the tutelary shrine forests, deep valleys and etc. From October 1988 to June 1989, phytosociological investigation of this forest vegetation was carried out by Braun-Blanquet s method. The forest vegetation was classified into 1 association and 7 communities. Ardisio-Castanopsietum sieboldii, Machilus thunbergii, Quercus acuta, Litsea japonca, Eurya japonica-Pinus thunbergii mixed forest, Pinus densiflora, Pinus rigida afforestation. Carpinus coreana community. Based on the classification, the actual vegetation map was drawn in 1 : 50,000 scale.

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