• 한국해양학회지
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• v.30 no.5
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• pp.480-492
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• 1995

Petrographic investigation has been carried out to determine the composition of the beach sediments and the affecting factors which have controlled their compositional variations from Hyupjae, Aeweol, Iho, Samyang, Hamdeok, Sehwa, Pyoseon, Jungmun, and Hwasun areas along the coast of the Cheju Island. Average mean sizes of the beach sediments are Hyupjae 2.2ø, Aeweol 0.8ø, Iho 1.4ø, Samyang 2.4ø, Hamdeok 1.6ø, Sehwa 1.5ø, Pyoseon 2.1ø, Jungmun 0.4ø, and Hwasun 0.9ø, thus, aries from 0.4 to 2.4ø. The beach sediments from Pyoseon and Hwasun areas are poorly sorted, those from Aeweol and Jungmun areas are moderately sorted and those from the rest of the areas are moderately well sorted. While-colored beach sediments in Hyupjae, Aeweol, Hamdeok, Sehwa, and Pyoseon areas are mostly composed of calcareous shells (more than 85%) such as mollusk, red algae, benthic foraminiferas, etc., whereas volcanic rock fragment is the dominant component of the black-colored beach sediments in Iho, Samyang, and Hwasun areas. Especially, the relatively white-colored beach sediment in Jungmun area, which is on e of the carbonate-dominant areas, shows a higher content of rock fragments than the other carbonate-dominant areas. The beach sediments in Pyoseon area show a high content of carbonate intercalates. Considering the contributions by organisms according to grain size, grains with the size range of 1∼2ø are mostly composed of calcareous red algae fragments, and grains with the size range of 2∼3ø consist of mollusk fragments. It is also notable that bryozoan fragments comprise about 48% of the sediment in Samyang area with the size range of 0∼1ø. The composition of the beach sediments in Cheju Island appears o be controlled by the riverine supply rate of volcanic rock fragments, the lithology of the rocks distributed ear the beaches, the direction of alongshore currents, and the direction of storms, etc.. It is suggested that the beach sediments in Iho and Samyang areas show black color because of the higher supply rate of the volcanic rock fragments from the nearby rivers, whereas those in the rest of the areas show white color due to the relatively lower content of volcanic rock fragments and higher content of carbonate components transported from shallow marine environment. In Hwasun area, the content of volcanic rock fragments is high, and they are directly from the tuffaceous rocks distributed nearby. Also, the volcanic rock fragments in Jungmun area are transported not only from the rivers nearby but also from the nearby tuffs by storm activities. The beach sediment in Pyoseon area contains a high content of carbonate intercalates, which formed in the nearby shallow marine environment through marine cementation. This indicates that active marine cementation occurs in shallow marine environment near Pyoseon area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.265-273
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• 1986

The marine algal communities of Yonhwa-do at the southern coast of Korea were investigated in aspects to quantitative analysis of their structure and dynamics. As a result, 114 species, including 2 blue-green, 69 red, 25 brown and 18 green algae, were identified. The R/P value(2.8) is higher than that of other regions of the southern coast of Korea. Sheet and filamentous groups of the functional groups of algae showed higher composition rate in spring and summer than in autumn and winter, but coarsely branched and thick leathery groups showed an opposite tendency. Cluster analysis based on species presence suggested the existence of 5 distinct groups in spring, but 3 groups in the other seasons. The species exhibiting important value above 20 were as follows: Porphyra suborbiculata, Corallina pilulifera, Hizikia fusiforme, Sargassum thunbergii, Undaria pinnatifida, Ishige okamurai, Chondria crassicaulis, and crustose coralline algae. The coverage of algal communities composed only of crustose coralline algal complex was higher than that of other algal complex, but occurrence frequency of these two communities was indifferent. It is suggested that the occurrence in high quantity of crustose coralline algae from this area is related to grazing by herbivorous animals.

• 한국해양학회지
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• v.22 no.4
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• pp.257-270
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• 1987

Fouling communities developing in Jinhae Harbor and Masan Bay were studied by slide and panel immersion test during the period from Dec., 1982 to Nov., 1983. The total viable count of bacteria was estimated more than 1.7${\times}$ 10$\^$4/CFU/$\textrm{cm}^2$ after 15 days of immersion and 46 taxa of benthic diatoms were classified in micro-community. Progressional change of fouling communities was clearly shown and dominant diatom species are Licmophora flavellata, Navicula grevillei, and Nitzschia closterium Major macrofouling organisms are Mytilus edulis, Balanus amphitrite amphitrite, Hydroides ezoensis, and Celleporina sp. Wet weight production of macrofouling organisms exceeds 500g/100cm$\^$2/ after 5months of immersion. Regional defferences in community development are clearly shown in two study areas, and mainly due to the disparities of physicochemical stability and nutritional status of ambient water. Seasonality of larvae and the growth rate are the important factors in fouling community development. Overall process of community development is as follow : bacteria and diatoms-multicellular algae-barnacle, mussels and polychaete-sponge, anemone and ascidian.

• The Journal of Natural Sciences
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• v.4
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• pp.11-22
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• 1991

Early studies on Korean Sargassum subjenus Bactrophycus were partly started by Kyetzubg(1843,1849), J. Agardh(1889), Cotton(1906), Yendo(1907) and Okamura(1913, 1914, 1915, 1917). Kang(1966) reported 15 species and 4 subspecies of Sargassum subgenus Bactrophycus and their wide distribution on the Korean coasts in his paper [On the geographical distribution of marine algae in Korea], a foundation stone of Korean phycology. In fact, all the Korean coasts and subtidal zone are inhabited by Sargassum plants. They constitute the most part of the primary production and dominant species of benthic algal vegetation. In 1974, L.K. Lee began to study Sargassum monographically as seaweed resources in Korea. The Koreans eat some species of Sargassum (including Hizikia fusiformis) or use them as fertilizer of the farm near the coast. Among the reported 17 species of Korean Fucales, 12 species belong to Bactrophycus. Yoo(1976) dealt with the descriptions, figures, and a key of 24 species of Korean Fucales plants in her M.S. thesis paper. Among them 16 species belonged to Bactrophycus. Even though the above two works were done with thorough observation of the dry specimens kept in the Pusan Fisheries University Herbarium (most of them were identified by Kang, J.W.) and nation-wide collections, great morphological varieties of these taxa made Lee and Yoo hesitate to publish the paper. Instead, the serial chemotaxonomic studies on the geographical variations of Korean Fucales plants(Yoo and Lee, 1988a, 1988b ; Yoo, et al., 1988) were held to solve the problem, while foreign papers (especially both Drs Tseng's and Yoshida's serial works on Bactrophycus). and authenthic specimens that foreign scholors sent to Korean phycologists induced them to find that several species of Sargassum had been misidentified from the beginning. We introduce here Korean Sargassum subgenus Bactrophycus according to Tseng et al. (1985), mentioning briefly the characteristics of the species, key, and distribution on the Korean coasts.

• Journal of Environmental Impact Assessment
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• v.27 no.1
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• pp.17-32
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• 2018

The need for seawater desalination is increasing in terms of securing various water resources, but few studies are available as for the environmental impact of hypersaline concentrated water (brine) discharged from desalination plants. Domestic studies are concentrated mainly on toxicity evaluation that phytoplankton, zooplankton larvae and green algae (Ulva pertusa) are negatively affected by concentrated water. The mortality of Paralichthys olivaceus showed a linear relationship with increasing salinity, and Oryzias latipes died 100% at concentrations above 60 psu. Foreign studies included monitoring cases as well as toxicity evaluations. The number of species decreased around the area where the concentrated water discharged. The hypersaline concentrated water affects the pelagic and benthic organisms. However, the fishes escaped when exposed to salinity, and the pelagic and benthic organisms resistant to salinity survived the hypersaline environment. The salinity limit and distance from the outlet was presented as the regulatory standard for bine discharge. There were differences in regulatory standards among country and seawater desalination plants, and these regulatory standards have been strengthened recently. In particular, California Water Boards were revised to ensure that the maximum daily salinity concentration does not exceed 2 psu above the ambient salinity level within 100 m of the outlet.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.186-194
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• 1998

Species composition and biomass of intertidal benthic algae were studied at the coast of Yonggwang Nuclear Power Plant area and its adjacent stations over 4 seasons (October 1995-August 1996), Of 68 species identified, 7 were Cyanophyta, 12 were Chlorophyta, 14 were Phaeophyta and 35 were Rhodophyta. The largest number of algal species (44) was found at Sangnok, the northernmost station of the study area, whereas the smallest number of species (15) was found from Tongho, ca. 13 km north of the power plant site. Number of species showed highest during the spring (44) and minimum was recorded in autumn (28). Biomass per unit area showed maximum in spring ($189.5\;g\;dry\;wt{\cdot}m^{-2}$ in average) and minimum in winter ($107.9\;g\;dry\;wt{\cdot}m^{-2}$ in average). Biomass values exhibited a wide range of variation among the stations, ranging from a low of $22.0\;g\;dry\;wt{\cdot}m^{-2}$ in annual average at Tongho to a high of $295.7g\;dry\;wt{\cdot}m^{-2}$ in average at Sangnok. Dominant species in biomass were Corallina pilulifera, Sargassum thunbergii, Gymnogongrus flabelliformis and Enteromorpha compressa. There have been little variation in the dominant algal species around the power plant site during the past 10 years and also these algae appeared throughout the west coast of Korea with higher frequency.

• Korean Journal of Environment and Ecology
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• v.29 no.5
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• pp.736-742
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• 2015

Cosmopolitan green macroalga, Ulva pertusa is a widely spread species in most coastal waters. This benthic alga is appearing on marine objectives causes significantly economical and social problems. To prevent fouling organisms, new antifouling (AF) agents, such as ziram, diruon, zinc pyrithione, copper pyrithione, DBNPA and triclosan are used. However, the evaluations of new antifouling system of those agents strongly need more information on algae species for considering environment effect. Therefore, the purpose of this study was to evaluate the activity of antifouling system using Ulva spores and Nitzschia pungens. In addition, new AFS were evaluated the toxicity of microalga, Nitzschia pungens. In the motility of Ulva spores, ziram and zinc pyrithione were shown 50% higher inhibition motility than diuron, copper pyritione, DBNPA and triclosan. Ziram was appered the highest AFS of Ulva sore attachment. Copper pyrithione at the concentration of $100{\mu}g/L$ was inhibited 80% growth rate comparison of control. In conclusion, each new AF agents showed their specific AF activities against marine organisms based on this work.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.4
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• pp.180-195
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• 2011

A balanced trophic model for Sinjido marine ecosystem was constructed using ECOPATH model and data obtained 1994 in the region. The model integrates available information on biomass and food spectrum, and analyses ecosystem properties, dynamics of the main species populations and the key trophic pathways of the system, and then compares these results with those of other marine environments. The model comprises 17 groups of benthic algae, phytoplankton, zooplankton, gastropoda, polychaeta, bivalvia, echinodermata, crustacean, cephalopoda, goby, flatfish, rays and skates, croaker, blenny, conger, flatheads, and detritus. The model shows trophic levels of 1.0~4.0 from primary producers and detritus to top predator as flathead group. The model estimates total biomass(B) of 0.1 $kgWW/m^2$, total net primary production(PP) of 1.6 $kgWW/m^2/yr$, total system throughput(TST) of 3.4 $kgWW/m^2/yr$ and TST's components of consumption 7%, exports 43%, respiratory flows 4% and flows into detritus 46%. The model also calculates PP/TR of 0.012, PP/B of 0.015, omnivory index(OI) of 0.12, Fin's cycling index(FCI) of 0.7%, Fin's mean path length(MPL) of2.11, ascendancy(A) of 4.1 $kgWW/m^2/yr$ bits, development capacity(C) of 8.2 $kgWW/m^2/yr$ bits and A/C of 51%. In particular this study focuses the analysis of mixed trophic impacts and describes the indirect impact of a groupb upon another through mediating one based on 4 types. A large proportion of total export in TST means higher exchange rate in the study region than in semi enclosed basins, which seems by strong tidal currents along the channels between islands, called Sinjido, Choyakdo and Saengildo. Among ecosystem theory and cycling indices, B, TST, PP/TR, FCI, MPL and OI are shown low, indicating the system is not fully mature according to Odum's theory. Additionally, high A/C reveals the maximum capacity of the region is small. To sum up, the study region has high exports of trophic flow and low capacity to develop, and reaches a development stage in the moment. This is a pilot research applied to the Sinjido in terms of trophic flow and food web system such that it may be helpful for comparison and management of the ecosystem in the future.