• Korean Journal of Environment and Ecology
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• v.31 no.6
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• pp.529-536
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• 2017

The study is intended to investigate the proliferation of whitening, the impact of climate change (sea temperature rise) on the proliferation of whitening, and the reproduction and growth of crustose coralline algae, which causes the whitening, in the coast of Jeju Island. The size of the whitening-affected area in the coast of Jeju was 2,931ha in 1998 and increased to 4,541ha in 2003. The whitening occurred mainly in the southern coast of Jeju in 1998 but spread across the whole coast of Jeju by 2003, except in the coast of Jocheon-eup (eup refers to an administrative district in Korea) and Gujwa-eup. The average sea water temperature in February from 1992 to 2004 was $15.1^{\circ}C$ in the whitening affected area and $13.9^{\circ}C$ in the marine forest area, showing a clear difference, but there was no difference in the average temperature in August. The long-term (37-year period) average of the sea temperature was $15.3^{\circ}C$ in the whitening affected area and $14.1^{\circ}C$ in the marine forest area, showing $1.2^{\circ}C$ higher in the whitening area. The annual rate of sea temperature rise was $0.038^{\circ}C$ in the whitening area and $0.024^{\circ}C$ in the marine forest area, indicating the higher long-term variation of sea temperature in the water affected by whitening. The results indicate that the continuous increase in winter water temperature due to climate change is expanding proliferation of whitening in the Jeju island.

• 어항어장
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• s.70
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• pp.30-33
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• 2005

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.271-272
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• 2001

최근 우리 나라의 연안은 갯녹음으로 황폐화되고 있으며, 이로 인하여 유용 수산자원이 감소하고 있는 실정이다. 이러한 갯녹음 현상은 서식지 환경요인들이 복합적으로 작용하고 있는 생태계의 변화로 연안의 암반은 산호말류로 피복되며 이들이 죽어서 하얗게 변하는 현상(정치ㆍ추강, 1980)으로서, 해중림과 산호말류 군집이 서로의 극상을 반복하는 생태적 현상으로 설명되기도 한다(중구, 1996). 갯녹음 지역의 유용 해중림 복원과 관련하여 갯녹음의 원인생물로 알려져 있는 포복성 산호조류의 종류와 그 생태를 파악하는 것은 무엇보다 시급한 과제이며 산호조류의 포자방출 패턴은 파악하는 것은 해중림 복원을 위한 효과적인 인공어초 투입의 시기를 결정하는데 중요한 요인이 된다. (중략)

• Korean Journal of Microbiology
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• v.38 no.2
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• pp.127-132
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• 2002

In this study, the bacterial communities distributed in sea water of the whitening areas of Gangjeong and Seongsan, Jeju-do have been analysed using the PCR amplification of 16S rRNA to obtain fundamental data and information on relationship of the whitening phenomenon and microbial ecosystem. In Gangjeong, diverse bacteria such as Alcanivorax, Paracoccus, Damselae, Pseudomonas, Rhodowlum, Silicibacter, Suiftobacter, and Roseobacter have been found, and Alcanivorax was the most abundant clone. The most abundant clone from Seongsan was Pseudomonas, of which Pseudomonas tolaasii and Pseudomonas mandeli were most abundantly occurred in the frequency of approx44% and 24%, respectively. Approx4% of the bacterial clones closest to Verrucomicrobiales and other unidentified clones were also fecund in Seongsan, suggesting there is a great discrepancy between bacterial communities from the whitening areas of Seongsan and Gangjeong. The mean temperature, chlorine concentration, pH, and dissolved oxygen (DO) of the sea water of Gangieong and Seongsan in August of 2001 (sampling period) was $27^{\circ}C$~$27.5^{\circ}C$, 30.24~30.60%, pH 8.23~8.36,7 .20~7.28 mg/ι, suggesting other environmental factors except far the factors mentioned above might result in difference of bacterial communities distributed in both areas.

• Proceedings of the Korean Aquaculture Society Conference
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• 2004.05a
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• pp.63-64
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• 2004

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.2
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• pp.212-219
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• 2019

This study was conducted to investigate marine algal community characteristics and the status of barren ground in the summer at study sites on Jeju Island, Korea. Sampling was carried out from July to September 2017 using a qualitative and quantitative survey (including coverage of non-geniculated coralline algae and density of grazer) by scuba diving. A total of 121 species were identified, including 11 (9.1 %) green algae, 24 (19.8 %) brown algae, and 86 (71.1 %) red algae. Hyeongjeseom had the greatest diversity, with 60 species, and Harye the least, with 18 species. The mean biomass at the study sites was $1,503.0g{\cdot}m^{-2}$, while the mean for the neighboring islets ($3,268.7g{\cdot}m^{-2}$) was higher than that of the main island ($914.7g{\cdot}m^{-2}$). Also, dominant species was identified: Sargassum macrocarpum at the neighboring islets, and Ecklonia cava at the main island, with differences showing not only in biomass but also species composition. In conclusion, the marine algal community status in summer at the study sites was evaluated based on the algal community characteristics (species composition, biomass, biomass ratio of kelp species), coverage of non-geniculated coralline algae, and density of grazer. As a result, both Hyeongjeseom and Marado require preservation and management to maintain their excellent marine algal communities, and other sites on the main island require the creation and/or restoration of marine algal communities. In addition, as the generation of barren ground accelerates, it is urgent not only to grasp existing monitoring research but also to identify the status of the marine algal community where it is not known at present.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.345-346
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• 2001

동해안은 최근 몇 년 사이에 갯녹음 현상으로 연안생태계에서 해조류가 쇠퇴하여 어패류의 먹이감소와 서식공간이 줄어드는 연안어장의 황폐화가 진행되고 있다. 갯녹음의 발생원인은 여러 가지 복합적 요인에 의해서 이루어지며, 특히 동해안과 같이 쿠로시오 난류세력의 영향이 미치는 곳에서 무절석 회조류의 번무와 함께 갯녹음역이 확산되는 것으로 알려져 있다 (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.367-368
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• 2001

해조류 자원은 해양의 1차 생산자로서 어, 패류의 먹이원이 되고 산란장이나 생활공간을 마련해 주게 됨으로 연안생물자원의 생산성을 높일 수 있다. 그러나 근래 갯녹음 현상으로 암초지대에 서식하는 해조숲이 줄어들고 바다가 황폐화되고 있다. 연안어장에 여러 종류의 바다생물이 서식하고 적극적인 자원조성을 하려면 우선 해조밭을 만들어 주어야 한다. 이 연구에서는 해조인공암초에 어떤 표면처리 조건이 바다숲 조성의 효율성을 높이는 것이 될 수 있는가를 검토하고자 하였다. (중략)

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.11a
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• pp.147-149
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• 2019

해수 온도의 상승과 해양 오염의 증가로 근래 국내 해안에서도 갯녹음이 확산되면서 바다숲이 축소되고 있다. 특히, 온난류의 유입에 의한 무절 석회조류의 난입과 해수에 함유 농도가 증가한 칼슘이 석출되고 해저 암반을 뒤덮어 해조류의 포자 활착 공간을 없애는 백화현상이 확산되면서 바다의 사막화 현상이 가속화되고 있다. 본 연구에서는 해조류의 포자가 빠르게 활착하여 안전하게 생장할 수 있는 공간을 제공하기 위한 새로운 방안으로, 먼저 육상에서 모판의 기능을 제공하여 해조류의 포자를 착상하여 성장시킨 후 해저로 이식하는 것으로 바다숲과 해안의 환경을 효과적으로 복원하기 위한 방안으로 다공성 기질 생태 플랫폼을 디자인하고 이의 특성 및 활용 방안을 제시하였다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.4
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• pp.180-191
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• 2015

Marine environmental characteristics and primary productivity of phytoplankton were investigated in seaweed bed of northwestern coast of Jeju Island during Autumn, 2014. The trophic state based on dissolved inorganic nitrogen and phosphorus was mesotrophic. The Redfield ratio was less than 16, indicating that nitrogen was the limiting factor for the growth of phytoplankton. Dissolved organic nitrogen and phosphorus accounts for 63 and 46% of the dissolved total nitrogen and phosphorus, respectively. Light utilization efficiency (${\alpha}$) and maximum photosynthetic capacity ($P_m{^B}$) were highest in the Donggwi (third-year marine forest), followed by Gonae (one-year marine forest), Biyangdo (natural seaweed bed) and Geumneung (whitening area). The primary productivity of phytoplankton in the Donggwi, Gonae and Biyangdo also was higher than that in the Geumneung. Although nitrogen is the limiting factor, enriched dissolved organic nitrogen might play an important role to maintain primary productivity. In addition, phytoplankton community through photosynthesis could produce about 14% of phytoplankton carbon in one hour. These results will be able to use the important information for material cycle and ecological valuation of seaweed bed.