• 한국수산과학회지
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• 제42권4호
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• pp.387-394
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• 2009

Marine algal flora and community structure were examined seasonally at four study sites around Taean Power Plant, Korea from Jan. to Nov. 2006. A total of 73 algae species (12 green, 9 brown, 52 red) and 1 marine plant were identified. The number of species was maximal at the power plant Discharge (57 species) site followed by Hakampo (46 species), Intake (28 species) and Breakwater (15 species) sites during the study period. The average biomass in dry weight varied from 13.12g/m2 at Intake to 69.60g/m2 at Hakampo. Dominant and sub dominant species in terms of biomass were Gelidium divaricatum - Ulva pertusa at Intake, Chondria crassicaulis - Ulva pertusa at Discharge, Corallin a pilulifera - Chondrus ocellatus at Breakwater, and Corallina pilulifera - Sargassum thunbergii at Hakampo. Species richness of warm tolerant and green algae were greater at Discharge site than Hakampo, showing similar species richness. However, community indices were not distinguishable between Discharge and other study sites. In conclusion, species richness and biomass of seaweeds were greater at Discharge site compared to intake and breakwater sites, and the abundance of warm tolerant and green algal species were higher than Hakampo.

• 한국수산과학회지
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• 제39권spc1호
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• pp.223-230
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• 2006

We investigated the spring and summer community structure of meiobenthos in a tidal-falt near Iwon, Korea, in 2002 and 2003. In total, 12 meiofaunal groups were found in the study area among which nematodes were the most dominant. Benthic foraminiferans, harpacticoid copepods, polychaetes, and crustacean nauplli were also dominant groups at all sites. The total density of meiobenthos at each station was be 246-2,177 ind./$10cm^2$. As the depth of sediment increased, the density of meiobenthos at each station gradually decreased. Changes in the vertical distribution of meiobenthos in the study area occurred mainly near the sediment surface (0-1 cm). Generally, between spring and summer the density of nematodes increased, and the density of other dominant meiofaunal groups (benthic harpacticoids, crustacean nauplii, benthic foraminiferans) decreased near the sediment trap the control site of sediment traps compared to that at the control site. The results of cluster and multidimensional scaling plots indicate that the meiofaunal community changed following construction of a low artificial wood groin structure.

• 한국수산과학회지
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• 제50권5호
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• pp.553-560
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• 2017

Fluctuations in the abundance and species composition of fishes in the coastal waters of Geumo-do, Yeosu, Jeollanam-do, Korea were investigated from 2002 to 2005. A gill net with entrances on both sides was used to collect a total of 469 individuals (55,180 g) of 3 orders, 18 families, and 28 species. The dominant species was Sebastes inermis (60 individuals, 5,670 g), followed by Neoditrema ransonneti (46 individuals, 2,290 g), and Pseudaesopia japonica (38 individuals, 3,080 g). The highest number of individuals was found in 2004, while the biomass was highest in 2005. The diversity index was highest in 2004 (H'=2.703) and lowest in 2002 (H'=2.580). The dominance index was highest in 2004 (D=3.983) and lowest in 2002 (D=3.404). The richness index was highest in 2003 (RI=0.337) and lowest in 2002 (RI=0.261). Changes in temperature and salinity affected the community structure and the location of spawning grounds. The number of individuals and total biomass increased with changes in temperature and salinity each year.

• 수산해양교육연구
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• 제27권1호
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• pp.300-307
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• 2015

Seasonal variation in marine macroalgal community structure was examined at the intertidal zones of Geumgap, Jindo, Korea, from October 2013 to August 2014. In total, 56 macroalgal species were identified, including 9 green, 12 brown, and 35 red algae. Annual seaweed biomass was 548.96 g wet wt. /$m^2$ with seasonal range between 371.08 g wet wt. /$m^2$ at summer and 32.91 g wet wt. /$m^2$ at winter. The dominant seaweed in terms of biomass was Sargassum thunbergii and subdominant species were Gelidium elegans, Sargassum fusiforme, and Ishige okamurae. The vertical distribution of seaweeds from the upper to lower intertidal zones was Gloiopeltis spp., Ulva spp.- S. thunbergii, S. fusiforme, Ishige okamurae - S. thunbergii, S. fusiforme, G. elegans. Annual seaweed coverage, richness index (R), evenness index (J'), and diversity index (H') values were 27.95%, 6.10, 0.38, and 1.38, respectively. Coarsely branched form was the most dominant functional group in terms of species number and biomass among benthic macroalgal species.

• 한국환경과학회지
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• 제19권11호
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• pp.1323-1336
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• 2010

This study was carried out to determine marine environments and phytoplankton community around Mokpo harbour on March to November during the period of 2004-2009. The remarkable fluctuations of marine environments were shown around Mokpo harbour depending on monthly and yearly. Among seasons, summer was a great that was associated with extremely releasing the freshwater from Youngsan River Weir, contributing to effect the fluctuations of water quality. Nevertheless of monthly and yearly, the molecular ratio of N:P was always shown in above 16 that was mainly attributed to freshwater discharge on March to November. This indicates that phosphorus playes an important role in limiting factor as growth in phytoplankton. During this study, Skeletonema costatum was found to be richer than the other groups of diatoms in terms of abundance and species number. Mokpo harbour, with the presence of a narrow avenue for exchange with offshore waters, has limited growth in phytoplankton, but this species is able to well adapt and fast grow under even high level of suspended solid and low intensity of light compared with other species. The discharge of freshwater is associated with significantly fluctuation of marine environments in this region, but it does not affect the quantitative and qualitative distribution of phytoplankton. It is necessary to persistently monitor based on water quality and phytoplankton community.

• 수산해양교육연구
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• 제21권4호
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• pp.568-575
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• 2009

On the conflict factors in using community fishing ground and their solutions, some conclusions are derived with the survey for fishing villages, residents, tourists as follows: Jeju Island has beautiful sceneries with seas in all the directions and so remarkable potential as personal experience fishing village. For sustainable development of ecological tourism in each fishing village, systematic, long-term development plans and management systems through decision making with residents in fishing and non-fishing villages are demanded. For tourist development of fishing village, protection management systems for marine and swampy land are needed first of all. Next, economical profit and the participation of resident have first priority, and also individual standards for each village are urgently prepared based on the results of basic research on each village. Finally, educations on environment and fishing village with professional tourist guide are needed. Ecological protection, environmental education, resident participation, local government's concern, and financial support could solve residential conflicts and make Jeju Island a Mecca of local fishing village tourism.

• 한국해양생명과학회지
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• 제6권1호
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• pp.9-22
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• 2021

We determined the composition of water and sediment bacterial assemblages from the East Sea using 16S rRNA gene sequencing. Total bacterial reads were greater in surface waters (<100 m) than in deep seawaters (>500 m) and sediments. However, total OTUs, bacterial diversity, and evenness were greater in deep seawaters than in surface waters with those in the sediment comparable to the deep sea waters. Proteobacteria was the most dominant bacterial phylum comprising 67.3% of the total sequence reads followed by Bacteriodetes (15.8%). Planctomycetes, Verrucomicrobia, and Actinobacteria followed all together consisting of only 8.1% of the total sequence. Candidatus Pelagibacter ubique considered oligotrophic bacteria, and Planctomycetes copiotrophic bacteria showed an opposite distribution in the surface waters, suggesting a potentially direct competition for available resources by these bacteria with different traits. The bacterial community in the warm surface waters were well separated from the other deep cold seawater and sediment samples. The bacteria exclusively associated with deep sea waters was Actinobacteriacea, known to be prevalent in the deep photic zone. The bacterial group Chromatiales and Lutibacter were those exclusively associated with the sediment samples. The overall bacterial community showed similarities in the horizontal rather than vertical direction in the East Sea.

• 해양환경안전학회지
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• 제25권3호
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• pp.354-365
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• 2019

Megabenthos samples were collected using 10-min trawls towed at 17 stations from 2015 to 2016. The dominant species (>1% of the total density) were Stegophiura sterea (10.4%) and two subtropical species, Mactrinula dolabrata (9.0%) and Acila divaricate (8.3%), respectively. The community structure of the megabenthos fell into four groups: the southeast, the southernmost region off Jeju Island, the frontal zone of the South Sea with C3, and a diagonal area from the south coast to the western side of Jeju Island. The total numbers of species, diversity, density and biomass were higher in the C3 region of the South Sea. Environmental factor analysis showed that differences in the megabenthos community were related to depth, gravel contents, and sorting value (${\sigma}$). These results indicate that changes in the marine environmental conditions in the South Sea of Korea affect the megabenthos species' composition and diversity.

• Fisheries and Aquatic Sciences
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• 제26권10호
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• pp.593-604
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• 2023

Post-harvest handling and hygienic level of aquatic products significantly affect the quality and level of safety. Cold chain control is one of the determining factors for the quality of fish and the bacterial community that grows on the fish. Identification of spoilage bacteria and pathogens in aquatic products must be made because it will determine the physical and chemical quality. A molecular identification method with high sensitivity is the solution. This study aims to identify the quality of fish and bacterial communities that grow. The research procedures included sample collection, pH measurement, drip loss measurement, transportation and cold storage treatment, DNA extraction, DNA sequencing, sequence analysis, and bioinformatics analysis. The conclusion obtained from this study is that the simulation of the cold chain system applied to eastern little tuna does not significantly affect changes in the water activity value, pH, and drip loss. The insignificant change indicates that the eastern little tuna samples are still in good quality. The bioinformatics analysis showed the highest diversity and abundance of the bacterial community came from the Gammaproteobacterial class.

• 해양환경안전학회지
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• 제15권2호
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• pp.99-104
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• 2009

진해만 조간대에서 서식하는 해조류 군집 구조를 파악하기 위하여 2007년에 8개 정점을 대상으로 계절별로 조사하였다. 조사기간 동안 총 45종의 해조류가 서식하였으며, 이 중 녹조류 4종, 갈조류 10종, 그리고 홍조류가 29종으로 나타났다. 우점종은 Ulva pertusa, U. conglobata, Sargassum horneri, Gelidium divaricatum, Gracilaria textorii, Polysiphonia morrowii으로 나타났다. 출현종수는 계절 및 정점에 따라 변하였다. 겨울에 가장 많은 42종이 출현하였으며, 여름에는 33종으로 가장 적었다. 정점별로는 정점 1,7,8에서 가장 많았으며, 정점 2와 3에서 가장 낮게 나타났나. 해조류 군집의 공간적 분포를 파악하기 위한 MDS 분석 결과에서는 해조류의 종조성 및 현존량이 각 정점의 물리해양학적인 특징 및 지형적인 차이에 의한 것으로 나타났나.