• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.1
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• pp.55-64
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• 2017

Seasonal variability in algal community structure was examined at the intertidal zones of five study sites on the Taean Peninsula, on the western coast of Korea, from February 2014 to November 2015. A total of 118 species of marine algae, comprising 17 green, 24 brown and 77 red algae, were identified. The maximum number of species was observed at the Mohang site (75 species), and the minimum at the Yeonpo site (46 species). The seaweed biomass was $160.24g\;dry\;wt./m^2$ on average, and was maximal at Uihang ($519.04g\;dry\;wt./m^2$) and minimal at Yeonpo ($19.03g\;dry\;wt./m^2$). Based on biomass, the dominant seaweeds at Taean peninsula were Sargassum thunbergii and Corallina pilulifera. Community indices were as follows: richness index (R), 3.21-5.01; evenness index (J'), 0.33-0.38; and diversity index (H'), 0.90-1.12. Based on evaluation of the environmental states by the community indices, the ecological evaluation index (EEI) of Taean peninsula was "moderate". The overall species and biomass of seaweeds decreased after the oil spill. However, Hakampo previously showed a similar algal community structure. In conclusion, the algal community was temporarily affected by the oil spill, but rapidly recovered.

• ALGAE
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• v.23 no.3
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• pp.231-240
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• 2008

The species composition and variation of benthic marine algae at Daejin and Jukbyeon on the mid-east coast of Korea were investigated seasonally from August 2006 to April 2007. As a result, the total of 85 species, including 8 chlorophytes, 26 phaeophytes, 50 rhodophytes and 1 sea grass were identified. 52 species were found at Daejin and 74 species at Jukbyeon. Dominant species in importance value were Corallina pilulifera, Chondrus ocellatus, melobesioidean algae, Sargassum horneri, Sargassum yezoense and Phyllospadix japonica at Daejin, and Corallina pilulifera, melobesioidean algae, Phyllospadix japonica, Acrosorium polyneurum, Sargassum siliquastrum and Hizikia fusiformis at Jukbyeon, respectively. The vertical distribution of algae were characterized by Corallina pilulifera, Hizikia fusiformis, Sargassum spp. (S. siliquastrum, S. yezoense) and Symphyocladia latiuscula at intertidal zone, Sargassum spp. (S. horneri, S. serratifolium, S. yezoense), melobesioidean algae, Phyllospadix japonica and Corallina pilulifera at 1 m depth, melobesioidean algae, Phyllospadix japonica and Sargassum spp. (S. horneri, S. yezoense) at 5 m depth and melobesioidean algae, Phyllospadix japonica and Sargassum spp. (S. horneri, S. micracanthum, S. yezoense) at 10 m depth.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.732-739
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• 2011

Marine algal flora and community structure were examined at four sites at Tongyeong, Korea, from February to December 2009. Eighty-two algal species were identified, including 10 green, 25 brown, and 47 red algae. During the study period, the number of species was highest at the Dukpo (61 species) site followed by the Gajodo (60 species), Yepo (58 species), and Chilchundo (53 species) sites. Seaweed biomass ranged from 578.11 to 678.26 g, with the maximum and minimum at Chilchundo and Yepo, respectively. Dominant species in term of biomass were Sargassum thunbergii at Yepo, Dukpo, and Gajodo and Gelidium amansii at Chilchundo. The vertical distribution from the high to low intertidal zone was Sargassum thunbergii and Chondria crassicaulis; Sargassum thunbergii and Ulva linza; Ulva pertusa, Sargassum fulvellum, and Gelidium amansii. Two groups clearly segregated in a cluster analysis, a Yepo/Dukpo group (group A) and a Gajodo/Chilchundo (B), indicating relatively strong differences in similarity. The seaweed community structure of group A was characterized by higher biomass and higher species richness of brown algae than were observed in group B. Additionally, the biomass ratio and the species richness of green algae was lower in group A. These differences in seaweed community structure may have been resulted from the effects of cold effluents.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.3
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• pp.91-102
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• 2016

The spatio-temporal variations of the dissolved methane concentration were investigated and the methane budget was estimated in the Nakdong Estuary in January, September, and November of 2014. Dissolved methane showed seasonal variation (21~874 nM) with high concentration in summer due to enhanced temperature and fresh water discharge. Decreasing trends of dissolved methane from the river to the estuary were consistent in all seasons showing the main source of the estuarine methane is river discharge. However, the decreasing trends were modified seasonally due to the local sources such as organic-rich sediments in intertidal zone or near the estuarine barrage. Dissolved methane concentration in the Nakdong Estuary was high, compared to other estuaries probably due to the well developed wetland in Nakdong-river system and stagnation effect from barrages and dams. Dominant sink for the Nakdong estuarine methane was outflux into the atmosphere. Relatively long residence time (produced by barrier island and estuarine dam) in the estuary might provide the enough time for the outgassing.

• Korean Journal of Ichthyology
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• v.35 no.1
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• pp.44-49
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• 2023

A single specimen of the genus Bothus (family Bothidae) was collected for the first time at the intertidal zone of Moseulpo Port, Daejeong-eup, Seogwipo-si, Jejudo Island, on 14 August 2022. The specimen was identified as Bothus pantherinus in having following morphological traits: dark spots and ring-shaped patterns near eyes and the pectoral fins, one distinct spot in the center of the lateral line, 75 lateral line scales, and seven hourglass shaped supracranial pterygiophores. As a result of analyzing 603 bp of mitochondrial DNA COI sequences, our specimen was perfectly matched to those of B. pantherinus registered in NCBI. It has been known that the species is widely distributed throughout the Indo-Pacific Ocean from Red Sea to Hawaiian (32 degrees north to 32 degrees south), but this study revealed that its distribution expanded to the waters of Jejudo Island (33 degrees north), Korea. We propose its new Korean name "Beot-kkoch-mu-nui-dung-geul-neob-chi".

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.3
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• pp.262-277
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• 2024

The mid-eastern coast of Korea is located at the boundary between cold and warm currents, which causes changes in the distribution and composition of marine organisms in response to fluctuations in the marine environment. To understand the seasonal changes in the seaweed community, we investigated its species composition, biomass, coverage, and frequency from November 2022 to August 2023. A total of 45 species (7 green, 18 brown, and 20 red algae) were found in the study area. In the intertidal zone, the number of species decreased from autumn to summer; the biomass peaked during winter (471.94 g wet weight m^-2). Seaweed groups were the dominant functional groups, which were coarsely branched, filamentous, and sheet-like during autumn, winter, spring, and summer. The morpho-functional group was dominated by turf species. In the subtidal zone, the number of species increased during autumn to spring, whereas the biomass peaked during spring (655.27 g wet weight m^-2). The functional group was dominated by coarsely branched species throughout all four seasons, whereas the morpho-functional group was dominated by canopy species. Consequently, changes in the biomass of brown and red algae are recognized as key drivers of seasonal changes in seaweed communities.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.439-448
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• 1999

To investigate the population dynamics and survival of Genus Vibrio, population densities of aerobic saprophytic bacteria and Vibrio groups were measured 4 times in the intertidal waters of the Yellow Sea near Kunsan from November, 1997 to June, 1998. The distribution of heterotrophic bacteria during the survey periods by plate count and direct count method ranged from 1.2$\pm$0.6$\times$10$^3$~2.0$\pm$1.5$\times$10$^4$CFU ml­$^1$and from 6.0$\pm$4.0$\times$10$^{5}$ ~1.9$\pm$1.5$\times$10$^{7}$ cells ml­$^1$, respectively. Vibrio groups were distributed in the range of 1$\times$10 and 6$\pm$2.2$\times$10$^2$CFU ml­$^1$. The proportion of Vibrio groups to total heterotrophic bacteria was between 0.1 and 6% during the survey periods. A total of 51 isolates was obtained from TCBS agar plates and identified to species level by Biolog Identification System$^{TM}$. As a result, dominant genera were V, mediterranei, V aitguillarum, tr metschnikovii, and V. parahaemolyticus, and isolates were clustered into 26 groups based on the relatedness of average linkage clustering method at 70% level. As for the susceptibility of 51 isolates to 7 kinds of antibacterial agents (gentamicin, ampicillin, chlorarnphenicol, streptomycin, kanamycin, tetracycline, carbenicillin), 96% of isolates showed high resistance to more than one antibiotics and 65% of isolates contained a plasmid, of which size was observed greater than 12 kb, The number of cells of 3 tested strains (V. anguillarum, V. vulnificus, and V. metschnikovii) in filtered aged seawater decreased by approximately 1 to 5 orders of magnitude during 30-d incubation. In most cases, the numbers of cells decreased rapidly until day 3, then decreased slowly by day 30. The number of cells incubated at 15$^{\circ}C$ showed higher survival than those at 4$^{\circ}C$ and $25^{\circ}C$. These results may be considered for the basic supporting data in the risk assessment of vibriosis in summer.r.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.8-18
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• 2005

We studied seasonal distribution of the microphytobenthos and their primary production with $C^{14}$ method and carried out pigment analysis with HPLC in an estuarine mudflat of the Ganghwa Island, Korea from May 2002 to April 2004. The abundances of microphytobenthos were higher at the middle than upper part and lower part of intertidal flat. Abundances of microphytobenthos ranged from $2.3{\times}10^5\;cells\;cm^{-2}$ to $140.9{\times}10^5\;cells cm^{-2}$. The bloom of microphytobenthos was observed in the early spring and then it decreased from spring to summer and autumn. The pennate diatom was a predominated group among the microphytobenthos in this area. The dominant species were Paralia sulcata, Cylindrotheca closterium and Nitzschia sp.. Nitzschia sp. and Cylindrotheca closterium were predominant in February. The results of pigment analysis suggest the presence of diatoms, euglenophytes, chlorophytes, cyanobacteria, cryptophytes, chrysophytes, prymnesiophytes, dinoflagellates and prasinophytes. The biomass of microphytobenthos ranged from 1.18 to 34.25 mg chl-a $m^{-2}$, with a mean of 7.60 mg chl-a $m^{-2}$. The mean ratio of Fuco/Chl a was 0.7 which indicates that most of biomasses of microphytobenthos were due to diatoms. The ratios of Chl b/Chl a ranged from 0 to 0.82(with a mean of 0.17), implying that euglenophytes and chlorophytes lived together in special period seasonally. Temporal variation of primary production ranged from 4.2 to 113.0 $mgC{\cdot}m^{-2}{\cdot}hr^{-1}$(mean value was 33.9 $mgC{\cdot}m^{-2}{\cdot}hr^{-1}$ and initial slope$({\alpha})$ was measured from 0.002-0.005$(mgC\;mgchl-a^{-1}\;hr^{-1}){\cdot}({\mu}E\;m^{-2}\;s^{-1})^{-1}$. Assimilation number$(P_m)$ was in the range of 0.50-1.32 $mgC{\cdot}mgChl-a{\cdot}hr^{-1}$ and daily primary production ranged from 20.9 to 678.1 $mgC{\cdot}m^{-2}{\cdot}d^{-1}$(mean value was 206.72 $mgC{\cdot}m^{-2}{\cdot}^{-1}$).

• Korean Journal of Environment and Ecology
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• v.28 no.1
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• pp.10-23
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• 2014

This study was carried out to examine seaweed community structure and distribution of crustose coralline algae at the intertidal and subtidal zones of Gallam, Samchuk, eastern coast of Korea. Total 112 species including 14 of green algae, 33 of brown algae, and 65 of red algae were collected and identified. Among these species, 29 species were found throughout the year. The dominant species which contributed significantly to the total biomass were Ulva pertusa, Colpomenia spp., Sargassum fulvellum, Sargassum fusiforme, Sargassum muticum, Sargassum thunbergii, Corallina pilulifera, and Gelidium elegans. Annual seaweed biomass in dry weight was 66.7 $gm^{-2}$ and maximum biomass was recorded seasonally in summer (107.5 $gm^{-2}$), while minimum was recorded in autumn (36.2 $gm^{-2}$). In seaweed functional group analyses, coarsely branched form was the most dominant functional group constituting from 40.0 to 48.6% of the total flora. Ecological state group ESG II, as an opportunistic species, including sheet form, filamentous form, and coarsely branched form, consisted of 46~61 species, constituting 76.7~82.4%. Crustose coralline algae was observed throughout all seasons. Species of the crustose coralline algae were largely classified into Lithothamnion lemoineae, Lithophyllum okamurai, Lithophyllum yessoense, and Hydrolithon gardineri. The coverage of crustose coralline algae seems to be lower than that of other studies from 36.8% to 11% on average.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.2
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• pp.119-129
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• 2015

Benthic marine algal flora and community structure at Chuksan on the mid-east coast of Korea were investigated seasonally from July 2007 to May 2009. Ninety-eight seaweed species were identified, including 13 green, 23 brown and 62 red algal species. The number of species found ranged between 33 and 63 among seasons. Two green (Ulva australis and Codium arabicum), three brown (Dictyota dichotoma, Sargassum fusiforme and Sargassum yezoense), and eleven red algae (Corallina pilulifera, Lithophyllum okamurae, Pachymeniopsis elliptica, Grateloupia filicina, G. cornea, Hildenbrandia rubra, Chondrus ocellatus, Acrosorium polyneurum, Chondria crassicaulis, Polysiphonia morrowii and Symphyocladia latiuscula) were observed throughout the survey period. Average marine algal biomass was $629.68g\;dry\;wt\;m^{-2}$ and it ranged seasonally from 119.30 to $1,660.96g\;dry\;wt\;m^{-2}$. The vertical distribution of marine algae was characterized by Corallina pilulifera and Sargassum spp. in the intertidal zone; Sargassum spp. at 1 m depth; Sargassum spp. and melobesioidean algae at 5 m depth; and melobesioidean algae at 10 m depth.