• Title/Summary/Keyword: coastal waters

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Copepods of the family Kelleriidae (Crustacea, Copepoda, Cyclopoida) from tropical waters of the Asia-Pacific

  • Hong, Jae-Sang;Kim, Il-Hoi
    • Journal of Species Research
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    • v.10 no.4
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    • pp.364-386
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    • 2021
  • Six species of the family Kelleriidae, including four new species, are recorded from tropical waters of the Asia-Pacific, two of them from Phuket Island, Thailand, one each from Bohol Island, Philippines and Phu Quoc Island, Vietnam, and two from Kosrae Island, Micronesia. A new genus Kelleriella is proposed to accomodate one of these new species (Kelleriella quadridens n. sp.). There are three diagnostic features of the new genus: the terminal segment of antenna is armed with one strong claw and six setae, the armature of the maxilliped endopod is reduced, and the third exopodal segment of leg 4 is armed with four spines and five setae. The other three new species are Kelleria latipes n. sp., Kelleria phuketensis n. sp., and Kelleria robusta n. sp. As diagnostic features of these new species, their caudal rami are about 2.5, 3.2, and 1.72 times longer than wide, respectively, the exopod of leg 5 of them is smooth, without any process, about 1.9, 3.7, and 2.9 times longer than wide, respectively, and armed with one spine plus one seta in Kelleria latipes and Kelleria phuketensis or with 2 setae in Kelleria robusta. Additionally, Kelleria javaensis Mulyadi, 2009 is synonymized with Kelleria regalis Gurney, 1927 and Kelleria grandisetiger Kim, 2006 is synonymized with Kelleria andamanensis Sewell, 1949, and both species are redescribed.

Genetic Structure of the Jellyfish Rhopilema esculentum (Scyphozoa: Rhizostomatidae) in Korean Coastal Waters

  • Soo-Jung Chang;Jang-Seu Ki;Won-Duk Yoon;Ga-Eun Jun
    • Animal Systematics, Evolution and Diversity
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    • v.39 no.4
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    • pp.264-271
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    • 2023
  • The edible jellyfish Rhopilema esculentum occurs in waters throughout northeastern Asia, including in Korea, China, and Japan. In Korean waters, R. esculentum has appeared in two regions (Gangwha and Muan). Based on the appearance of young medusae and coastal distribution records, these two regions may be key R. esculentum breeding sites. In the present study, we investigate and compare the genetic structure of R. esculentum in the two regions using mitochondrial sequences (16S ribosomal RNA and cytochrome c oxidase subunit I). The genetic diversity of the R. esculentum population at Ganghwa exceeded that of the population at Muan. Despite considerable geographic separation (400 km) between the two regions(Gangwha and Muan), our haplotype network suggests that the Gangwha and Muan populations of R. esculentum are related. The simple and monotonous genetic structure of the Muan population shows that R. esculentum emergence is relatively recent. In contrast, the Gangwha population shows evolution. Moreover, jellyfish of the Gangwha population are genetically diverse and remain constant despite environmental fluctuations in the Han River. The Gangwha area is considered to be the old origin of R. esculentum in Korea.

Seasonal distribution of marine organisms in the surface layer around nuclear power plants using acoustic (원자력발전소 주변 표층해역에 출현하는 해양생물의 계절별 음향산란 분포)

  • Eun-Bi MIN;Tae-Jong KANG;Yeongtae SON;Doo-Jin HWANG
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.60 no.1
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    • pp.9-17
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    • 2024
  • In this study, the seasonal distribution was surveyed using acoustic in the coastal waters around nuclear power plants. Acoustic surveys were conducted in June, September, December 2022, and March 2023 in the coastal waters of Uljin-gun. According to the results of this study, zooplankton were distributed at the depths from 0 m to 50 m in the waters around nuclear power plants. Zooplankton appeared in summer (June), autumn (September), and spring (March). In the survey area, fish were distributed at the depths from 25 m to 190 m, appearing in the summer (June), autumn (September), winter (December) and spring (March). The SV of zooplankton appearing in the survey area ranged from -98.0 dB to -78.0 dB, and it exhibited a one-class in the frequency distribution of SV. The SV of fish appearing in the survey area ranged from -36.0 dB to -35.0 dB and -98.0 dB to -53.0 dB, and it exhibited two-class in the frequency distribution of SV.

Warming Trend of Coastal Waters of Korea during Recent 60 Years (1936-1995)

  • Kang Yong Q.
    • Fisheries and Aquatic Sciences
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    • v.3 no.3_4
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    • pp.173-179
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    • 2000
  • Recent changes in the coastal sea surface temperatures (SST) in Korea are studied by time series analysis of daily SST data during the last 60 years (1936-1995) at 18 coastal observation stations of the National Fisheries Research and Development Institute. The climate of coastal SST in Korea are rapidly changing in recent years. General trends of coast SST changes in Korea are as follows. The annual averages of SST are increasing. The annual ranges of SST variation are decreasing. The winter SST are increasing while the summer SST have a decreasing tendency. Climatic changes in coastal SST in recent 30 years (1965-1995) are more pronounced than those in the last 60 years (1936-1995). The observed trend of coast SST implies that the climate in Korea shows a tendency to shift from temperate zone to subtropical zone.

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CIRCULATION AND WATER MASSES IN THE CONTINE NTAL SHELF BREAK REGION OF THE EAST CHINA SEA (동지나해 대륙붕 연변의 해수 유동과 수괴)

  • Lim Gi Bong;Fujimoto Minoru
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.5 no.1
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    • pp.1-10
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    • 1972
  • Studies on the circulation and water masses in the continental shelf break region of the East China Sea are Summerized as follows : 1. The main stream of the Kuroshio flowing north-east near $29^{\circ}N\;Lat\;127^{\circ}E$ tong of the East China Sea in summer is narrow in width. Moving toward east, it becomes twice as wide in Tokora Strait, Japan. 2. In the main stream area of the Kuroshio, the surface Waters in the Upper layer (0-250m) are influenced by the coastal waters of China, and the counter current submerges under the surface water. Therefore, the mixing waters are found in its intermediate layer. 3. Water mass between Amami Island and the continental shelf of the East China Sea consists of main stream water, counter current water, gyration water and mixed water with coastal waters. 4. The maximum velocity of current in this waters was 139cm/sec. The volume transport was estimated approximately as $24.2\;\times\;10^6m^3/sec$. It was less than $33\;\times\;10^6m^3/sec$ in the region between Okinawa and continental shelf of the East China Sea. 5. Surface waters east of $29^{\circ}N\;Lat\;128^{\circ}E$ Long flows toward Amami Island, Okinawa Island, and Hachi Ju San Island, while those west of the region flow toward the Korea-strait, Cheju Island, coastal waters of Kyusyu, and the Pacific Ocean through Tokora Strait. The velocity of the current was estimated approximately as $0.3\~0.5$ miles per hour. 6. The bottom waters in the continental shelf break region flow toward the Korea Strait, Cheju Island and the coastal water of Kyusyu, while that of the continental shelf flows toward the Yellow Sea, 7, The characteristics of the Kuroshio water is changed remarkably by the mixing with the coastal water of China.

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Redescription of the Glasseye Snapper Heteropriacanthus cruentatus (Perciformes: Priacanthidae) from the coastal waters of Jeju Island, Korea (제주도 연안에서 채집된 뿔돔과(Priacanthidae) 큰눈홍치 Heteropriacanthus cruentatus (Perciformes: Priacanthidae)의 재기재)

  • Choi, Youn;Lee, Heung-Heon
    • Korean Journal of Ichthyology
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    • v.22 no.2
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    • pp.126-128
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    • 2010
  • Morphological characters of Heteropriacanthus cruentatus are redescribed in detail based on a single specimen (179.3 mm SL) collected from the coastal waters of Jeju Island, Korea. The species is characterized by dark brown spots scattered on the caudal fin and the soft-rayed portions of the dorsal and anal fins, and 59 pored lateral line scales.

Basic Design of Multipurpose Fisheries Base for Marine Ranching Program (바다목장화를 위한 다목적 수산기지의 기초설계)

  • Kim, Hyeon-Ju;Lee, Na-Ry
    • Journal of Ocean Engineering and Technology
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    • v.13 no.4 s.35
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    • pp.143-150
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    • 1999
  • Multipurpose fisheries base was conceptually designed to establish marine ranching system in the coastal waters around Tongyoung, southern sea of Korea. Fisheries base for marine ranching system has integrated various facilities which were required for the process of spawning, rearing, training, releasing, monitoring and catching functions. This base has five steel piles for supporting upper structure and systems. Four steel piles are surrounded by circular net pen made by steel wire, they have the function of the protection against fouling for pile and scouring for bottom soil as well as secondary rearing and short stocking. We can use the last pile to moor a ship and access to the base. Principal structure with steel piles is designed by optimization technique considering design external forces in the coastal waters of return period of 50 years. Design optimization Problem is formulated for this base. Optimal design of multipurpose fisheries base is numerically investigated by sequential quadratic programming method.

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Identification of Albula sp. (Albulidae: Albuliformes) Leptocephalus Collected from the Southern Coastal Waters of Korea using Cytochrome b DNA Sequences

  • Kim, Byung-Jik;Kim, Sung;Seo, Hyun-Seok;Oh, Jin-A
    • Ocean Science Journal
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    • v.43 no.2
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    • pp.101-106
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    • 2008
  • A single specimen of Albula leptocephalus (55.7 mm SL) was collected from the southern coastal waters of Korea using an aquatic lamp. It is characterized by having a ribbon-like body with a small head and a well-forked caudal fin. Although the general appearance was similar to the leptocephalus of A. vulpes including myomere counts and fin ray counts, the melanophore deposition was different from that of A. vulpes. This leptocephalus specimen was confirmed with A. forsteri using the cytochrome b mtDNA (Cytb) analysis. The genetic distance of Cytb between the present leptocephalus and A. forsteri is 0.006-0.038, which falls into the cutoff point separating Albula species into eight deep lineages including the four valid species. Its genetic characteristic have more similarities to those of Fiji than those of Hawaii and the Northern territory of Australia.

Sequence Analysis of Cochlodinium polykrikoides Isolated from Korean Coastal Waters Using Sequences of Internal Transcribed Spacers and 5.8S rDNA

  • Kim, Hak-Gyoon;Cho, Yong-Chul;Cho, Eun-Seob
    • Journal of the korean society of oceanography
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    • v.35 no.3
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    • pp.158-160
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    • 2000
  • The relativity of four isolates of C. polykrikoides was determined by comparative sequence analysis based on direct sequencing of PCR amplified ribosomal DNA (the internal transcribed spacer region and the 5.8S rDNA). Sequence comparisons indicated that four isolates had the same nucleotide sites in the ITS regions, as well as a total of 585 nucleotide length and 100% homology. The molecular data revealed that C. polykrikoides in Korean coastal waters show no genetical difference.

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Phytoplankton of the Coastal Waters of Vladivostok (the North-western Part of the East Sea) under Eutrophic Conditions

  • Stonik, I.V.;Orlova, T.Yu.
    • Ocean and Polar Research
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    • v.24 no.4
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    • pp.359-365
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    • 2002
  • The qualitative and quantitative composition of the phytoplankton of the coastal waters off Vladivostok during the period 1991-1994 was studied. The following trends in the phytoplankton composition with decreasing distance from the source of eutrophication were revealed: 1) total density and bio-mass increased; 2) the density of the diatom Skeletonema costatum, which reflects a decrease in the Shannon-Weaver species diversity index during the summer microalgal bloom, increased significantly; and 3) the density of the non-diatom component of the phytoplankton increased.