• Applied Biological Chemistry
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• 제49권4호
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• pp.266-269
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• 2006

송이버섯 균사체의 biomass를 위한 최적조건을 규명한 결과, 균사체 spot배양을 위한 최적 조건은 MMN배지를 사용하여 pH 5.5에서 탄소원으로 현미를 3% 첨가 하여 $24^{\circ}C$에서 35일 배양 시 최적인 것으로 판단하였으며, 송이버섯 균사체 Biomass를 위한 bioreactor의 배양 최적조건은 PDMP배지를 사용하여 $18^{\circ}C$에서 60일 배양 시 reactor의 반응은 최적의 상태를 나타낼 수 있을 것이라 판단되었다.

• 수산해양교육연구
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• 제25권6호
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• pp.1336-1347
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• 2013

The marine algal flora assemblages settled on the artificial seaweed reefs in Jeju-do before and after rocky cleaning were investigated during summer and the early succession of seaweeds attached to the test panels on the structures of the artificial reef after rocky cleaning were observed by visual observations and under the dissecting microscope in order to evaluate the effects of this rocky cleaning operation. Species composition and algal biomass on the Bboolsamgak-typed seaweed artificial reefs before and after rocky cleaning were measured and compared before and after rocky cleaning. Before rocky cleaning in July 2012, only nine algal species had existed on the Bboolsamgak-typed seaweed artificial reefs, however, twenty algal species occurred on the seaweed artificial reefs after rocky cleaning in July 2013. Particularly, 15 species among them in July 2013 were not found in July 2012 and they seemed to occur newly on the artificial reefs. A large quantity of algal biomass increased in July 2013 after rocky cleaning. Based on the importance value, there was a drastic change in the dominant species between July 2012 and July 2013 after rocky cleaning. By dissecting micrographs, an epiphytic diatom, Licmophora sp. and flagellates, were observed on the 9th day. A chlorophyte, Ulothrix flacca was observed after 14 days, Ulva pertusa, Bryopsis pulmosa, crustose coralline algae, and Cladophora spp. were after one month. After two months, a significant species succession was observed from three previous chlorophyte species to crustose coralline algae existed as a dominant species on the panels. In this study, however, any brown algae were not found until three months in the early seaweed succession. All above results indicates that the rocky cleaning is a very efficient method for the establishment of macroalgal assemblages on the artificial reefs.

• 한국수산과학회지
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• 제54권6호
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• pp.1007-1016
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• 2021

This study examined the characteristics and seasonal distribution patterns of subtidal marine algal communities along the east coast of Korea, from 2016 to 2017, and recorded the coverage ratio (%) by the algal type. During the study period, 134 marine algae species (16 green, 29 brown, and 89 red) were identified at the survey sites. The maximum number of species was observed at the Nagok site (70 species), and the minimum at the Gisamoon site (50 species). The total average biomass (dry weight) during the survey period was 66.22 g/m², including green algae (2.19 g/m²), brown algae (38.10 g/m²), and red algae (25.94 g/m²). The dominant seaweeds in the vertical distribution based on coverage rates (%) were Sargassum yezoense and Dictyopteris divaricata at the upper, Symphyocladia latiuscula and Undaria pinnatifida at the middle, and Agarum clathratum subsp. yakishiriense and Plocamium telfairiae at the lower sections of the distribution. Richness, evenness, and diversity index, calculated based on the biomass of the abundant species, were estimated to be 6.36, 0.55, and 1.98, respectively, over the entire sea area. Based on the evaluation of the environmental states using community indices, the ecological evaluation index (EEI-c) of subtidal marine algal communities along the east coast of Korea was marked as 'good-moderate'.

• ALGAE
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• 제26권4호
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• pp.333-342
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• 2011

Macroalgae are important primary producers in marine ecosystem. They don't only play an important role as bioindicators but also provide economic resources for humans. Seasonal and vertical variations in seaweed species composition and biomass were examined to determine the ecological status of seaweed beds around Udo, near Jeju Island. We obtained samples at two sites in the high-intertidal to subtidal zones using the quadrat method between June 2010 and May 2011. A total of 262 species were collected, including 31 green, 61 brown, and 170 red algae. The composition of algal species revealed a decrease in species growing in cold water in comparison with the list 20 years ago. The macroalgal mean biomass (g wet wt $m^{-2}$) was 3,476 g and 2,393 g from the two sites, respectively. Ecklonia cava had the greatest biomass at both sites. The seasonal dominant species by biomass at site 1 from the low-intertidal to 1-3 m depth of the subtidal zone was mostly comprised of thick-leathery form, such as Sargassum hemiphyllum, S. coreanum, and Ecklonia cava, whereas site 2 was comprised of the turf form, such as Chondrophycus intermedius, Chondracanthus intermedius, Dictyopteris prolifera, and Gelidium elegans. The current ecological status of the seaweed community in Udo is stable based on diversity and dominance indices.

• 수산해양기술연구
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• 제48권4호
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• pp.445-451
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• 2012

We developed an age-based spawner-recruit model incorporating environmental variables to forecast stock biomass and recruits of pelagic fish in this study. We applied the model to the Tsushima stock of jack mackerel, which is shared by Korea and Japan. The stock biomass of jack mackerel (Trachurus japonicus) around Korean waters ranged from 141 thousand metric tons (mt) and 728 thousand mt and recruits ranged from 27 thousand mt to 283 thousand mt. We hind-casted the stock biomass to evaluate the model performance and robustness for the period of 1987~2009. It was found that the model has been useful to forecast stock biomass and recruits for the period of the lifespan of fish species. The model is also capable of forecasting the long-term period, assuming a certain climatic regime.

• Applied Biological Chemistry
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• 제50권1호
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• pp.1-5
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• 2007

새송이버섯의 biomass를 위한 최적조건을 규명한 결과, 균사체 spot 배양을 위한 최적 조건은 PDA배지를 사용하여 24$^{\circ}C$에서 18일 배양 시 최적인 것으로 판단하였으며, 새송이버섯 균사체 Biomass를 위한 bioreactor의 배양 최적조건은 PDMP배지를 사용하여 pH 5.5, 18$^{\circ}C$에서 27일 배양시 reactor의 반응은 최적의 상태를 나타낼 수 있을 것이라 판단되었다. 최적조건에서 bioreactor를 이용한 새송이버섯 균사체의 인공적인 대량 배양이 가능하였으며, bioreactor에서 대량 인공 배양된 균사체를 이용한 새송이버섯 재배 시, 자실체가 형성되어 새송이버섯의 대량생산을 위한 biomass가 가능하였다.

• ALGAE
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• 제28권1호
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• pp.101-109
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• 2013

Some Chlorella species grow heterotrophically with organic substrate in dark condition. However, heterotrophic Chlorella species are limited and their optimum culture conditions are not fully known. In this study, three heterotrophic Chlorella species, two strains (C4-3 and C4-4) of C. vulgaris and one Chlorella sp. (C4-8) were examined on optimum culture conditions such as carbon source, temperature, and concentrations of nitrogen and phosphorus in Jaworski's medium (JM). And the growth and fatty acid composition of Chlorella were analyzed. For three heterotrophic Chlorella species, glucose (1-2%) as a carbon source only increased the growth and the range of optimum culture temperature was $26-28^{\circ}C$. Doubled concentrations of the nitrogen or phosphorus in JM medium also improved the growth of Chlorella. Chlorella cultured heterotrophically showed significantly higher growth rate and bigger cell size than those autotrophically did. C. vulgaris (C4-3) cultured heterotrophically showed the highest biomass in dry weight ($0.8g\;L^{-1}$) among three species. With respect to fatty acid composition, the contents of C16:0 and n-3 highly unsaturated fatty acid (HUFA) were significantly higher in autotrophic Chlorella than in heterotrophic one and those of total lipid were not different between different concentrations of nitrogen and phosphorus in JM medium. Among three Chlorella species in this study, C. vulgaris (C4-3) appeared to be the most ideal heterotrophic Chlorella species for industrial application since it had a high biomass and lipid content.

• 수산해양기술연구
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• 제50권4호
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• pp.551-555
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• 2014

ADCPs have been widely used to estimate the dynamic characteristics and biomass of sound scattering layers (SSLs), and swimming speed of fish schools for analyzing SSLs spatial distribution and/or various behavior patterns. This result showed that the verification of the mean volume backscattering strength (MVBS or averaged SV, dB) acquired by the ADCP would be necessary for a quantitative analysis on the spatial distribution and the biomass estimation of the SSLs or fish school when ADCP is used for estimating their biomass. In addition, the calibrated sphere method was used to verify values of each MVBS obtained from 4 beams of ADCP (153.6 kHz) on the base of 3 frequencies (38, 120, 200 kHz) of Scientific echo sounder's split beam system. Then, the measured SV values were compared and analyzed in its Target Strength (TS, dB) values estimated by a theoretical acoustic scattering model.

• Ocean and Polar Research
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• 제33권spc3호
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• pp.337-347
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• 2011

We investigated latitudinal changes in mesozooplankton community structure during a cruise between October 16 and November 30 of 2007 from four distinctive regions in the northwestern Pacific Ocean: Warm pool area (longitude $135^{\circ}$ line), Philippine EEZ (PEEZ), Japan EEZ (JEEZ), and East China Sea (ECS). Major taxa of numerical importance were Clausocalanidae (Clausocalanus spp.), Oncaeidae (Oncaea spp.), and Oithonidae (Oithona spp.) in oligotrophic regions, however Paracalanidae (Paracalanus spp.) was the most abundant group in the ECS. Mesozooplankton size group of <1 mm dominated in PEEZ and WP (48% and 56%, respectively), but mesozooplankton (>1 mm) were of importance in the JEEZ and ECS (34% and 38%, respectively). Mesozooplankton biomass and abundance were high in the JEEZ and ECS, and low in the oligotrophic WP and PEEZ waters, with positive relationship with both total Chl-a and heterotrophic protist biomass. Latitudinal change in mesozooplankton community structure was related with water temperature, with copepods such as Lucicutia spp. and Pleuromamma spp. being present only in warm waters. The geographical expansion of mesozooplankton with a preference for warmer waters could potentially be useful as an indicator for detecting ocean warming.

• 수산해양교육연구
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• 제23권2호
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• pp.141-152
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• 2011

This study was investigated the species composition of demersal fishes by a bottom trawler GAYA, in order to be used basic data for resources management of fishery in the jointly controlled waters of the West sea. We caught 39 species, 5,532 individuals and 322.518kg in biomass. The number of species was the fewest of the jointly controlled waters of the East china sea and boundary zone between Busan and Tsushima. The first dominant species in individuals in summer was Oregonia gracilis, and in biomass was angler. But angler was the first dominant species in 7 stations of 12 stations. It was a peculiar phenomenon that cod which lives in a cold current was caught in the northern part of the West sea. In this connection it seems to be needs for oceanographic research. Catch per unit effort (kg/hr) of bottom trawl was the higher in northern part and in right line of all surveyed area respectively.