• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.3
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• pp.296-302
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• 2013

The effects of temperature on spore release, growth and photosynthetic efficiency of Lithophyllum yessoense and Hildenbrandia rubra were examined. L. yessoense was collected at Galnam and H. rubra was collected at Gyeokpo, Korea. The experimental temperatures were different for spore release (10, 15, $20^{\circ}C$), sporeling growth (10, 15, 20, 25, $30^{\circ}C$) and photosynthetic efficiency (10, 15, 20, $25^{\circ}C$). All other culture conditions were the same: 34 psu, 12:12 LD and $50{\mu}mol$ photon $m^{-2}s^{-1}$. Spore liberation was maximal at $10^{\circ}C$ for L. yessoense and at $20^{\circ}C$ for H. rubra. After 14 days, the surface area of L. yessoense was 0.031 $mm^2$ at $25^{\circ}C$ and for H. rubra was 0.032 $mm^2$ at $20^{\circ}C$. Sporelings of L. yessoense were a dark-red color and grew in a round shape. In contrast, H. rubra was bright pink and changed from a round shape in the early growth stage to later become flabelliform. Photosynthetic efficiency was highest between $20-25^{\circ}C$ in both species. In conclusion, L. yessoense and H. rubra display different physiological features based on the optimal temperatures for spore release and sporling growth.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.827-834
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• 2013

The effects of environmental factors, such as irradiance, daylength, salinity, and desiccation, on the growth of Lithophyllum yessoense and Hildenbrandia rubra sporelings were examined. Sporelings of each species were cultured with 10, 50, 80, 120, $150{\mu}mol$ photon $m^{-2}s^{-1}$ for 14 days and their maximum growth occurred under $80{\mu}mol$ photon $m^{-2}s^{-1}$. Germlings of both species survived for 21 days in darkness, and even the L.yessoense germlings grew. In the salinity experiment, sporelings of each species survived for 7 days and died after 14 days under 20 and 25 psu, but the sporelings grew well under 34 psu. Physiological features of each species with respect to the evaluated daylengths (8, 12, 14 and 16 h) were slightly different, and maximal growth occurred at 16 h for L. yessoense and at 14 h for H. rubra sporelings. Mortality of the sporelings increased with the exposure period, but H. rubra was less tolerant to desiccation than L. yessoense. In conclusion, sporelings of the two species showed similar growth responses to various environmental factors with slightly different physiological features with respect to salinity, daylength, and desiccation. However, more ecological and physiological studies on slow-growing crustose algae are required to elucidate the expansion of barren ground around the coastal areas of Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.878-885
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• 2013

Seasonal variation in marine macroalgal community structure was examined at the intertidal zones of Heuksando and Hongdo, Shinan, Korea, from July 2008 to May 2009. In total, 86 macroalgal species were identified, including 12 green, 19 brown, and 55 red algae; 67 species at Heuksando and 70 species at Hongdo, were observed. Annual seaweed biomass was 252.44 g dry $wt/m^2$ at Heuksando and 217.67 g dry $wt/m^2$ at Hongdo. The dominant seaweed in importance value (IV > 15) differed between the sites: Sargassum thunbergii at Heuksando and Corallina pilulifera at Hongdo. The vertical distribution pattern of seaweeds from the upper to lower intertidal zones at Heuksando was Gloiopeltis spp., Ulva spp. - S. thunbergii, S. fusiforme, Hildenbrandia rubra - S. thunbergii, C. pilulifera. On the rocky shore of Hongdo, seaweed zonation was distinct: Porphyra yezoensis, Gloiopeltis spp., Ulva spp. - C. pilulifera, S. fusiforme, Myelophycus simplex - Chondrus ocellatus, C. pilulifera, and Carpopeltis affinis. Annual seaweed coverage, richness index (R), evenness index (J'), and diversity index (H') values were greater at Hongdo (41.35%, 12.82, 0.59, and 2.50 respectively) than at Heuksando (31.54%, 11.93, 0.44, and 1.87 respectively), which may indicate that the seaweed community at Hongdo is more stable relative to the one at Heuksando.

• 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.