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Seaweed aquaculture beds (SABs) that support the production of seaweed and their diverse products, cover extensive coastal areas, especially in the Asian-Pacific region, and provide many ecosystem services such as nutrient removal and CO2 assimilation. The use of SABs in potential carbon dioxide (CO2) mitigation efforts has been proposed with commercial seaweed production in China, India, Indonesia, Japan, Malaysia, Philippines, Republic of Korea, Thailand, and Vietnam, and is at a nascent stage in Australia and New Zealand. We attempted to consider the total annual potential of SABs to drawdown and fix anthropogenic CO2. In the last decade, seaweed production has increased tremendously in the Asian-Pacific region. In 2014, the total annual production of Asian-Pacific SABs surpassed 2.61 × 106 t dw. Total carbon accumulated annually was more than 0.78 × 106 t y−1, equivalent to over 2.87 × 106 t CO2 y−1. By increasing the area available for SABs, biomass production, carbon accumulation, and CO2 drawdown can be enhanced. The conversion of biomass to biofuel can reduce the use of fossil fuels and provide additional mitigation of CO2 emissions. Contributions of seaweeds as carbon donors to other ecosystems could be significant in global carbon sequestration. The ongoing development of SABs would not only ensure that Asian-Pacific countries will remain leaders in the global seaweed industry but may also provide an added dimension of helping to mitigate the problem of excessive CO2 emissions.

A major goal of phylogeographic analysis using molecular markers is to understand the ecological and historical variables that influence genetic diversity within a species. Here, we used sequences of the mitochondrial Cox1 gene and nuclear internal transcribed spacer to reconstruct its phylogeography and demographic history of the intertidal red seaweed Chondrus ocellatus over most of its geographical range in the Northwest Pacific. We found three deeply separated lineages A, B and C, which diverged from one another in the early Pliocene-late Miocene (c. 4.5-7.7 Ma). The remarkably deep divergences, both within and between lineages, appear to have resulted from ancient isolations, accelerated by random drift and limited genetic exchange between regions. The disjunct distributions of lineages A and C along the coasts of Japan may reflect divergence during isolation in scattered refugia. The distribution of lineage B, from the South China Sea to the Korean Peninsula, appears to reflect postglacial recolonizations of coastal habitats. These three lineages do not coincide with the three documented morphological formae in C. ocellatus, suggesting that additional cryptic species may exist in this taxon. Our study illustrates the interaction of environmental variability and demographic processes in producing lineage diversification in an intertidal seaweed and highlights the importance of phylogeographic approaches for discovering cryptic marine biodiversity.

We report the marine algal flora at the seashore of Oho-ri, Gosung-gun, Gangwon-do in this note. The seashoreof Gosung-gun has predominantly sandy substrate withsome rocky outcrops. The algal habitat of the easterncoast of Korea is generally restricted because of the steepslope and small tidal range.The survey on flora was performed at 3 islets (the seasurface-protruding rocky outcrops), including Heukdo,Goraebawi, and Juckdo. The marine algal vegetation ofJuckdo had reported (Koh, 1983; Koh and Sung, 1983).It had mentioned 42 species in the community researchon marine algae from July 1982 to June 1983.This study aimed to establish an inventory of algalspecies inhabiting Oho-ri coast nearby the eastern NLL(the Northern Limit Line), Gangwon-do, Korea. This areawas a selected region for the project “The Survey onSpecies Diversity of Strategic Regions (2010)” in Nati-onal Institute of Biological Resources(NIBR).

Chung, I. K., Oak, J. H., Lee, J. A., Shin, J. A., Kim, J. G., and Park, K.-S. 2013. Installing kelp forests/seaweed beds for mitigation and adaptation against global warming: Korean Project Overview. – ICES Journal of Marine Science, 70: 1038–1044. Seaweed beds can serve as a significant carbon dioxide (CO2) sink while also satisfying global needs for food, fodder, fuel, and pharmaceutical products. The goal of our Korean Project has been to develop new baseline and monitoring methodologies for mitigation and adaptation within the context of climate change. Using innovative research approaches, we have established the Coastal CO2 Removal Belt (CCRB), which comprises both natural and man-made plant communities in the coastal region of southern Korea. Implemented on various spatial–temporal scales, this scheme promotes the removal of CO2 via marine forests. For example, when populated with the perennial brown alga Ecklonia, a pilot CCRB farm can draw down ∼10 t of CO2 per ha per year. This success is manifested by an increment in biomass accumulations and a decrease in the amount of dissolved inorganic carbon in the water column.

We constructed planktonic 18S rDNA clone libraries for micro-organisms in the euphotic zone of the Ulleung Basin in the East Sea of Korea. They revealed the cryptic biodiversity of eukaryotic planktons and demonstrated specific phylogenetic affiliations at certain water depths. Dinoflagellate clones dominated at the surface and 75-m depth. Members of the Syndiniales order (Groups I and II), containing wellknown parasitic dinoflagellates, as well as one their prominent hosts, Polycystinea, were found exclusively at 75 m. These observations suggest that the presence of species from Groups I and II is closely related to the specific water mass. Therefore, their metagenomics information might be useful for delineating both water-mass and physico-chemical properties.

Nitrate reductase (NR) is activated by nitrogen sources (NO3 - and NH4 + ) and irradiance. This study investigated the effects of these factors on the NR activity of Ulva pertusa (Chlorophyta) and Ecklonia cava (Phaeophyta). In addition, the ammonium (NH4 + ) and nitrate (NO3 - ) uptake rates of the two species were examined. U. pertusa took up most of the NO3 - and NH4 + in the medium during a 3hour incubation, while E. cava had a relatively high uptake rate after 3 hours. The NR activities of the two species were affected by the nitrogen source and irradiance and were highest when they were exposed to NO3 - -rich medium and high irradiance. However, the patterns of NR activity differed between the two species. In NO3 - -rich medium and high irradiance, U. pertusa achieved the highest NR activity (2.01 ± 0.07 μmol NO2 - g -1 DW h -1 ) within the first 3 hours and then this activity decreased drastically. By contrast, the NR activity of E. cava (0.36 ± 0.04 μmol NO2 - g -1 DW h -1 ) was constant for 12 hours. When exposed to darkness, the NR activity of U. pertusa decreased dramatically, while that of E. cava increased gradually for 12 hours. Therefore, E. cava is able to maintain NR activity during the dark because of its adequate carbohydrate reserves and substrate.

SUMMARY The usefulness of molecular phylogenetic studies has increased remarkably as the quantity and quality of available DNA sequences has increased. When compared with the progress that has occurred in angiosperms and animals, there have been relatively few target DNA regions identified for use in taxonomic studies of brown algae. Therefore, in this study, we developed a new set of primers to amplify Rubisco small subunit (rbcS) gene sequences and determined the rbcS gene sequences of various species of brown algae including those belonging to Dictyotales, Ectocarpales, Fucales and Sphacelariales. The level of sequence variations in the rbcS gene varied according to the brown algal lineages. When focusing on the relationship of species within the genus Sargassum, the rbcS gene sequences provided useful information regarding the phylogenetic relationship among sections of the subgenus Bactrophycus. Based on the broad applicability and phylogenetic utility of the rbcS gene, we suggest that the sequence be used as a new target region for the molecular systematics of brown algae.

Using chlorophyll fluorescence, the vertical migration of benthic diatoms responding to light intensity and affected by sediment grain size was studied. Minimal fluorescence ( F o ) of surface sediment was measured by imaging pulse ampli- tude modulated (Imaging-PAM) fluorometer, and used to monitor diatom biomass variation in surface sediments. The test diatoms, Amphora coffeaeformis (C. Agardh) Kutzing and Cylindrotheca closterium (Ehrenberg) Reimann & Lewin, migrated to the sediment surface under irradiance from 50 to 500 µmol photons m -2 s -1 . However, the diatoms exhibited no evident increase of surface biomass under dark conditions, and even showed slightly decrease of surface biomass under irradiances over 1,000 µmol photons m -2 s -1 . The light intensity inducing the maximum surface migration of A. coffeaeformis was 100 µmol photons m -2 s -1 , while the light intensity producing the same effect for C. closterium was 250 µmol photons m -2 s -1 . C. closterium showed higher motility than A. coffeaeformis. Faster diatom surfacing was observed in larger grain size sediments (125-335 µm) than smaller ones (63-125 µm). This study confirmed the significant influ - ence of light as a main triggering factor behind migration, indicated the distinct effect of different sediment grain size, and highlighted the species-specific migratory ability.

Phytoplankton are primary producers and can be important indicators of environmental change. To monitor the plankton species composition of environmental seawater samples, we developed a molecular method composed of colony polymerase chain reaction (PCR), polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP), and sequencing. A clone library of the ribosomal small subunit RNA gene (18S rDNA) in the nuclear genome was constructed by environmental PCR using a newly designed primer set and clones were directly amplified by colony PCR. To select unique putative clones, we choose a PCR-RFLP method that employed two restriction enzymes (MseI and Tsp509I). After the PCR-RFLP pattern was evaluated, selected clones were sequenced and analyzed. In this study, we revealed the hidden biodiversity in environmental seawater containing a wide range of taxonomic groups in the Alveolata (Ciliphora and Dinophyceae), Euglenozoa, Stramenopiles (Bacillariophyta), and Viridiplantae (Chlorophyta) without the need to conduct extensive colony isolation techniques. Moreover, we found species of fungi and Metazoa (Arthropoda, Annelida, and Mollusca). Therefore, this improved molecular method can be used to generate a robust database describing the species diversity of environmental samples and provide useful information regarding the dynamics of the eukaryotic plankton community structure.

Enrichment in nutrients coming from urban sewage outfalls can lead to eutrophication in coastal areas, which can also change the species composition and community structure of macro algal communities. We investigated the structure of the macro algal community within three rocky shores in order to assess any possible differences in their characteristics. Site 1 was located near Tongyeong city`s sewage outfall, Site 2 was located near a public beach area, and Site 3 faced open channel of the Ocean. All three sites were located within the same stretch of the coast, where Site 2 was located between sites 1 and 3. We measured the nutrient concentration in water and the tissue nitrogen content in macro algae samples. Nutrients in the water column surrounding site 1 were high in ammonium (), nitrate (), and phosphate () content, and were characterized by low numbers of macroalgal species and species and a low species diversity index. In contrast, site 3 exhibited relatively low nutrient concentration levels and a high number of macroalgal species and a high species diversity index. Comparative analysis showed that the tissue nitrogen content of macroalgae were significantly (P

Porphyra yezoensis is known to act as a biofilter against nutrient-rich effluent in seaweed-based integrated aquaculture systems. However, few studies have examined its physiological status under such conditions. In this study, we estimated the photosynthetic activity of P. yezoensis by chlorophyll fluorescence of PSII ( and relative ) using the Diving-PAM fluorometer (Walz, Germany). In addition, bioremediation capacity, tissue nutrients, and C:N ratio of P. yezoensis were investigated. The ammonium concentration in seawater of seaweed tank 4 decreased from to after 24 hours. This indicates the potential role of P. yezoensis in removing around 43% of ammonium from the effluents. Tissue carbon contents in P. yezoensis were constant during the experimental period, while nitrogen contents had increased slightly by 24 hours. In comparison with the initial values, the and of P. yezoensis had increased by about 20 and 40%, respectively, after 24 hours. This indicates that P. yezoensis condition improved or remained constant. These results suggest that chlorophyll fluorescence is a powerful tool in evaluating the physiological status of seaweeds in a seaweed-based integrated aquaculture system.

【Seaweed biomass was estimated using a nondestructive method in the rocky subtidal zones in Munseom, Jeju Island, Korea from July 2006 to April 2008. Seasonal samplings were done at the depth of 1, 5, 10 m using 50 x 50 cm quadrat. Mean biomass was comprised of 2,784 g wet wt m $^{-2}$ and the biomass values varied seasonally from 1,176 g wet wt m $^{-2}$ to 4,217 g wet wt m $^{-2}$ with the highest point in April. Biomass reached maximum at 5 m depth in spring, but was shifted to 10 m depth in summer. Common seaweeds appeared year round in Munseom were Codium minus, Ecklonia cava, Sargassum spp., articulated corallines and Plocamium telfairiae. Among them, E. cava showed the highest biomass (average of 1,288 g wet wt m $^{-2}$ ), comprising 4% of total biomass. Only 12 species’' biomass covered 98% of total value, which indicated the contribution of few common species to algal community. Seaweed biomass in Munseom represented one of the highest values in coastal regions in Korea.】

Generic boundaries among the genera Cheilosporum, Haliptilon, and Jania—currently referred to the tribe Janieae (Corallinaceae, Corallinales, Rhodophyta)—were reassessed. Phylogenetic relationships among 42 corallinoidean taxa were determined based on 26 anatomical characters and nuclear SSU rDNA sequence data for 11 species (with two duplicate plants) referred to the tribe Corallineae and 15 species referred to the tribe Janieae (two species of Cheilosporum, seven of Haliptilon, and six of Jania, with five duplicate plants). Results from our approach were consistent with the hypothesis that the tribe Janieae is monophyletic. Our data indicate, however, that Jania and Haliptilon as currently delimited are not monophyletic, and that Cheilosporum should not be recognized as an independent genus within the Janieae. Our data resolved two well-supported biogeographic clades for the included Janieae, an Indian-Pacific clade and a temperate North Atlantic clade. Among anatomical characters, reproductive structures reflected the evolution of the Janieae. Based on our results, three genera, Cheilosporum, Haliptilon, and Jania, should be merged into a single genus, with Jania having nomenclatural priority. We therefore propose new combinations where necessary of some species previously included in Cheilosporum and Haliptilon.

Collections from subtidal habitats often include various tiny delesseriacean algae. Assigning them to appropriate positions has frequently been difficult, especially between Delesseria and Apoglossum. Apoglossum was erected as a subgenus of Delesseria Lamouroux by J. Agardh (1876) and later was elevated to the generic level by the same author (Agardh 1898). Agardh (1898) distinguished Apoglossum from Hypoglossum Kutzing, considered as a related genus, primarily by the presence of conspicuous microscopic lateral veins and the irregular arrangement of cells. Confusions in generic criteria, however, occurred in relation to Delesseria rather than to Hypoglossum because the above characteristics can be found in both. Kylin (1923) clarified the both genera after a close examination of their type species. Currently accepted features to identify Apoglossum are mainly based on Kylin (1923) and Wynne (1984): 1) intercalary cell divisions are absent in the primary cell row but occur in the higher order cell rows, 2) not all the third order cell rows reach the blade margin, 3) branches arise from the midrib, 4) lateral pericentral cells remain undivided, 5) when the midrib is cross sectioned, rhizoidal cells are confined to either side of the central large cells, 6) the fourth order cell rows are on the adaxial but not on the abaxial side of the third order rows, and 7) each sterile cell group remains single. When establishing Apoglossum, J. Agardh (1898) included six species, A. decipiens (J. Agardh) J. Agardh, A. montagneanum (J. Agardh) J. Agardh, A. oppositifolium (Harvey) J. Agardh, A. tasmanicum (Mueller) J. Agardh, A. violaceum (J. Agardh) J. Agardh, and the type species A. ruscifolium (Turner) J. Agardh. Two of them, A. violaceum and A. decipiens, were transferred to Delesseria by Kylin (1924). Five more species, A. minimum Yamada, A. punctatum Dawson, A. spathulatum (Sonder) Womersley et Shepley, A. gregarium (Dawson) Wynne and A. unguiculescens Millar, were newly added from Japan, Mexico and Australia (Yamada 1944; Dawson 1966; Womersley and Shepley 1982; Wynne 1985; Millar 1990; Millar and Wynne 1992); among them, A. punctatum was reduced to a synonym of Grinnellia lanceolata Dawson (Wynne 1985). The genus Apoglossum, therefore currently including eight species, has been known to occur in British waters, the Mediterranean, South Africa, the eastern Pacific Ocean, Australia, New Zealand, and Japan (Greville 1830; Harvey 1849; Yamada 1944; Womersley and Shepley 1982; Wynne 1984, 1985; Ballantine and Wynne 1985; Millar and Wynne 1992; Maggs and Hommersand 1993; Silva et al. 1996). We collected Apoglossum species from the subtidal zone as a first record in Korea and identified as previously known species, A. minimum from Japan and A. gregarium from the Gulf of California. We described their morAlgae Volume 21(4): 425-432, 2006

Two species of marine algae, Fauchea spinulosa Okamura et Segawa (Rhodymeniaceae, Rhodophyceae) and Stictyosiphon soriferus (Reinke) Rosenvinge (Chodariaceae, Phaeophyceae) were newly collected from the southern coast and Cheju Island of Korea. Fauchea spinulosa was collected from subtidal zone in the insular region of the southern coast. Plants were erect from the discoidal holdfast with short stipe, pinkish to deep red, cartilageneous, dichotomously and flabellately branched, and 10-15 cm high, 5-15 mm broad. Tetrasporangia are cruciately divided and nemathecia occurred on a side of the branches. Cystocarps were mostly coronate in marginal area and spermatangia were scattered on both sides of branches. Stictyosiphon soriferus commonly occurs on muddy and sandy intertidal flat of Namhaedo located on the southern coast. Plants are epilithic, light brown, terete, 3-5 cm high, and branched heavily in irregular or alternate manner, arising from a small holdfast with rhizoidal clumps. Plurilocular sporangia were scattered in patches and slightly swollen above the cortex of the whole filament. Unilocular sporangia were not found.

Eight species of Sargassum subgenus Bactrophycus section Teretia were collected from the coasts of Korea: S. confusum C. Agardh, S. pallidum (Turner) C. Agardh, S. muticum (Yendo) Fensholt, S. thunbergii (Mertens ex Roth) Kuntze, S. fulvellum (Turner) C. Agardh, S. hemiphyllum (Turner) C. Agardh, S. nipponicum Yendo, and S. miyabei Yendo. These species were investigated on morphological variations and geographical distribution in Korea. The valuable taxonomic characters between similar species of this section were discussed with special reference to thickness of leaves, types of holdfasts, shape of leaves and vesicle, and length of rhizoids.

The taxonomic status of three closely related species of the genus Sphacelaria, S. rigidula Kutzing, S. fusca (Hudson) C.F Gray and S. didichotoma Saunders was reassessed on the basis of morphological observations from herbarium specimens and phylogenetic analysis of RUBISCO spacer sequences. Sphacelaria rigidula was characterized by having only 2-armed propagules and somewhat slender filaments. Culture experiments revealed that its propagules commonly formed secondary arms, even though they were rarely produced in the field. It is concluded that S. divaricata Montagne characterized by dichotomously branched arms in propagules shoud be synonymized with S. rigidula, based on propagule morphology and measurements. Sphacelaria fusca clearly be separated from S. rigidula by having 2-4 armed propagules. These morphological differences were highly supported by the differences in the RUBISCO spacer sequences. S. didichotoma resembles S. rigidula in having propagules with two dichotomously branched arms. However, it commonly produces the secondary arms in the field. Additionally, this species has shorter primary arms than S. rigidula. Phylogenetic analyses supported the distinction of S. didichotoma from S. rigidula. The northwestern Pacific plants, previously recorded as S. divaricata, were recognized as S. didichotoma.

A more rapid and efficient method to extract RNA from Ecklonia cava Kjellman (Laminariales, Phaeophyceae) was introduced in this study. Each step of the procedure was evaluated and the optimal concentration of each chemical in the lysis solution was determined. Tissue pulverization with PVPP and β-mercaptoethanol in the lysis solution were not essential for RNA extraction of this species. The highest yield and purity of E. cava RNA were obtained by the lysis solution containing 1% CTAB, 1 M NaCl, 0.7% PVP, 10mM EDTA and 100mM Tris-Cl (pH 9.0). Approximately 8μg of RNA was obtained from 200 mg of ground tissue. The ratios of the absorbance at 260 nm and 280 nm were from 1.6 to 1.8 and those of at 230 nm and 260 nm were from 1.8 to 2.0. The extracted RNAs obtained in this study turned out to have a sufficient quality for cDNA synthesis.Ā

Five species of Hypoglossum from the coasts of Korea were described. They were distinguished each other by vegetative morphology as well as reproductive structures. H. barbatum Okamura and H. simulans Wynne, Price et Ballantine were similar in their subalternate branchings but they were clearly different by developmental mode of 3rd-order cell rows. H. simulans is distinguished from H. barbatum as well as from the other three species in that only innermost cells of 2nd-order rows cut off 3rd-order cell rows. H. geminatum Okamura and H. caloglossoides Wynne et Kraft are oppositely branched but the latter is characterized by regular constrictions at branching points. H. minimum Yamada developed simple blades. Among them, H. simulans, H. caloglossoides, and H. minimum are newly recorded from Korean waters.

We report the potential phylogenetic utility of the small RUBISCO subunit (rbc S) sequences from a sampling of Antithamnion and related genera in ceramiacean algae. The size of rbc S was 417 bp for all taxa examined. Analyses of the DNA sequence data indicated that pairwise divergences of rbc S sequences were 3.3%–9.8% among species of Antithamnion, and ranged from 13.6% to 18.0% between Antithamnion and related genera. Phylogenetic analyses fully resolved relationships at the intrageneric level with statistical significance supported by high bootstrap values. Two subgenera of Antithamnion, Pteroton and Antithamnion, were clearly distinguished in the molecular tree. In the clade of subgenus Pteroton, A. aglandum was allied with A. callocladum and separated from A. nipponicum. In the pairwise distance comparison of sequence variation, Ceramium showed the greatest genetic distances among genera examined in the study. All phylogenetic trees generated by the maximum parsimony, neighbor joining, and maximum likelihood were completely congruent in topology with high confidence.

The conserved region of numerous MADS genes in gulfweed (Sargassum fulvellum) was cloned by PCR with degenerate primers. Analysis of seventy individual clones resulted in the identification of nineteen types of nucleotide sequences. There sequences encode portions of the MADS domain in four distinctive groups. Six clones belong to the AGAMOUS subfamily, ten to AGL2, and two to AGL12. The remaining one clone is distinctive and appears to be diverged from an ancestor of the AGL2 and AP1 groups. There were no A or B class MADS genes. These results suggest that, as found in land plants, MADS genes also play major roles in controlling the development of algae.

Four species of Sphacelaria producing tribuliform propagules in the section Tribuloides were distinguished from each other on the basis of the branching pattern and propagule morphology including the division type of the subapical cells and the shape of the lateral apical cells. Sphacelaria plumula shows complanate tufts composed of erect filaments bearing pinnate determinate laterals arranged in one plane, while the other species, S. tribuloides, S. brachygonia and S. novae-caledoniae, form erect tufts with irregular indeterminate branches. Sphacelaria tribuloides is distinguished by typical tribuliform propagules with acute conical lateral apical cells. Sphacelaria plumula has slightly larger propagules with obtuse conical lateral apical cells and a rather vague constriction at the waist. The distinguishing features of S. brachygonia are its slightly tribuliform, more often transversely ellipsoid propagules with round conical lateral apical cells and small lower parts under the waist. In S. novae-caledoniae, the filaments are slender and its mature propagules have the rectangular lateral apical cells produced by 2-3 longitudinal and transverse divisions of the subapical cells. The morphometric features of segments, propagules and zoidangia in the species of the section Tribuloides, including S. californica and S. novae-hollandiae, were found to be variable, but in some species they can be used to distinguish taxa. In addition, the holotypes of S. cornuta and S. nipponica, previously placed in the section Tribuloides, were examined. The results suggest that S. cornuta can be considered as a synonym of S. tribuloides, and S. nipponica should be placed in the section Furcigerae, based on the presence of diagonal divisions in the subapical cells as well as long stalks and prominent arms in the propagules.