• ALGAE
• /
• v.31 no.3
• /
• pp.243-256
• /
• 2016

Concerns about how ocean acidification will impact marine organisms have steadily increased in recent years, but there is a lack of knowledge on the responses of macroalgae. Here, we adopt an outdoor continuous-flowing mesocosm system designed for ocean acidification experiment that allows high CO₂ conditions to vary with natural fluctuations in the environment. Following the establishment of the mesocosm, five species of macroalgae that are common along the coast of Korea (namely Ulva pertusa, Codium fragile, Sargassum thunbergii, S. horneri, and Prionitis cornea) were exposed to three different CO₂ concentrations: ambient (×1) and elevated CO₂ (2× and 4× ambient), over two-week period, and their ecophysiological traits were measured. Results indicated that both photosynthesis and growth exhibited species-specific responses to the different CO₂ concentrations. Most notably, photosynthesis and growth increased in S. thunbergii when exposed to elevated CO₂ conditions but decreased in P. cornea. The preference for different inorganic carbon species (CO₂ and HCO₃⁻), which were estimated by gross photosynthesis in the presence and absence of the external carbonic anhydrase (eCA) inhibitor acetazolamide, were also found to vary among species and CO₂ treatments. Specifically, the two Sargassum species exhibited decreased eCA inhibition of photosynthesis with increased growth when exposed to high CO₂ conditions. In contrast, growth of U. pertusa and C. fragile were not notably affected by increased CO₂. Together, these results suggest that the five species of macroalgae may respond differently to changes in ocean acidity, with species-specific responses based on their differentiated photosynthetic acclimation. Understanding these physiological changes might allow us to better predict future changes in macroalgal communities in a more acidic ocean.

• ALGAE
• /
• v.28 no.3
• /
• pp.233-240
• /
• 2013

Despite specimens' large size and ease of collection in northeast Asian waters, the species diversity of the genus Grateloupia still needs more research in Korea. We investigated plastid rbcL sequences and carried out detailed morphological observation on flattened halymeniacean red alga collected in twelve locations around Korea and Japan. We describe Grateloupia jejuensis sp. nov. based on the distinct clade with high support in our rbcL tree. Grateloupia jejuensis is characterized by solitary or caespitose habit and flattened thalli with discoid holdfast, cartilaginous texture, and blunt or bifid axis. Grateloupia jejuensis was distantly related to G. elata and G. cornea, which have been morphologically confused with the former, and it formed a sister relationship with Prionitis filiformis from California, USA in the rbcL tree.

• ALGAE
• /
• v.22 no.4
• /
• pp.313-318
• /
• 2007

Studies have been made of the species composition and community structure of benthic marine algae at intertidal zone and subtidal zone of Youngdo at Busan. In this area, a total of 69 marine algal species including 10 Chlorophyta, 17 Phaeophyta and 42 Rhodophyta was identified. Dominant species in coverage were Enteromorpha linza, Ulva pertusa, Gelidium divaricatum, Hildenbrandtia rubra and Chondrus ocellatus throughout the year. Enteromorpha linza, Ulva pertusa, Porphyra yezoensis, Gelidium divaricatum, Corallina pilulifera, Grateloupia elliptica and Chondrus ocellatus vertically distributed in intertidal zone, while Ecklonia stolonifera, Gelidium amansii, Prionitis cornea, Gracilaria textorii, Acrosorium polyneurum and Phycodrys fimbriata in subtidal zone. The vertical distribution of subtidal zone were characterized by Ecklonia stolonifera at 1 to 5 m depths. During a year, biomass and length of Ecklonia stolonifera gradually decreased from March to January, but increased from February. Zoosporangial sori were observed from September to December. In conclusion, number of species in this area was remarkably reduced as compared to the previous data at Busan and it’s vicinity.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.42 no.6
• /
• pp.664-673
• /
• 2009

An intertidal marine benthic algal vegetation and vertical distribution at Youngil Bay, the eastern coast of Korea was investigated to clarify the community structure and vertical distribution by quadrat method from February 2003 to January 2009. Marine algae identified from the area were 152 species; 25 green, 38 brown and 89 red algae. The dominant species were Ulva spp., Ulva pertusa, Chaetomorpha moniligera, Undaria pinnatifida, Sargassum horneri, S. miyabei, S. thunbergii, Gelidium amansii, Corallina pilulifera, Grateloupia elliptica, G. filicina, Prionitis cornea, Chondrus ocellatus, Chondracanthus intermedia, Acrosorium polyneurum, Chondria crassicaulis, Polysiphonia morrowii and Symphyocladia latiuscula at study sites. The vertical distribution of intertidal marine algae was divided into three distinct zones. They were characterized by Porphyra spp. and Ulva spp. at the upper, Ulva spp. and Ulva pertusa at the middle, and Sargassum spp., Gelidium amansii, Grateloupia spp., Chondrus ocellatus and Chondria crassicaulis at the lower zones, respectively. Functional form group analysis showed that coarsely branched forms comprised 44.7% of the algal community, whereas thick leathery forms, sheet forms and filamentous forms comprised 6.6-25.7%. R/P, C/P and (R+C)/P values were 2.34, 0.66 and 3.00, respectively.

• Journal of Environmental Science International
• /
• v.22 no.6
• /
• pp.761-771
• /
• 2013

The species composition and variation of marine plants at Saguenjin in the east coast of Korea were investigated monthly from October 2008 to December 2009. As a result, 92 species of marine plants identified, 91 species were seaweeds (7 green algae, 22 brown algae, 62 red algae) and 1 were sea grass. Dominant species in importance value were melobesioidean algae, Ulva pertusa and Phyllospadix iwatensis. The vertical distribution of algae were characterized by melobesioidean algae, U. pertusa at 3 m depth, melobesioidean algae, P. iwatensis and U. pertusa at 5 m depth and melobesioidean algae, Chondrus ocellatus and Prionitis cornea at 10 m depth.

• Ocean Science Journal
• /
• v.43 no.1
• /
• pp.31-37
• /
• 2008

As a part of an ongoing search for antioxidants from marine sources, antioxidant activities of 24 kinds of seaweeds (4 green algae, 8 brown algae, and 12 red algae) were investigated. The seaweeds were extracted by acetone/dichloromethane and methanol, respectively. The antioxidant properties of both extracts were evaluated using four different activity tests, including degree of occurrence of intracellular reactive oxygen species (ROS), NO, lipid peroxidation, and GSH (glutathione) in mouse macrophage Raw 264.7 cells. The levels of intracellular reactive oxygen species (ROS) and GSH were measured using 2',7'-dichlorofluorescin diacetate (DCFDA) and monobromobimane as fluorescence probe, respectively. Moreover, the generation of NO and lipid peroxidation products were determined by each method based on the Griess reaction and TBARS assay. Solvent extracts from seaweeds such as Scytosiphon lomentaria, Prionitis cornea, Laruencia okamurae, Callophyllis japonica, Sargassum horneri, Dictyopteris divaricata, Lomentaria catenata, Corallina confuse, Ishige okamurae, and Ahnfeltiopsis flabelliformi exhibited high antioxidant activities in cellular oxidizing systems.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.44 no.1
• /
• pp.85-94
• /
• 2011

The species composition and distributions of benthic marine plants on the East Coast of Korea were studied. We examined all species found in the intertidal and subtidal zones at four sites seasonally from August 2006 to May 2009. Of the 148 species identified, 92 were rhodophytes, 39 were phaeophytes, 16 were chlorophytes, and 1 was a seagrass. The most species (125) were found at Jukbyeon, while the fewest (99) were found at Chuksan. Overall, the numbers of species were highest during the spring and lowest in autumn. Seventy-five species (50 rhodophytes, 15 phaeophytes, 9 chlorophytes, and 1 seagrass) were found at all four sites. The dominant species providing cover were melobesioidean algae, Sargassum spp., Phyllospadix japonica, and Corallina pilulifera. The vertical distribution of benthic marine plants was characterized by C. pilulifera, Sargassum spp., Hizikia fusiformis, Grateloupia elliptica, Symphyocladia latiuscula, Grateloupia lanceolata, Ulva pertusa, and Chondria crassicaulis in the intertidal zone; Sargassum spp., P. japonica, Prionitis cornea, C. pilulifera, and Acrosorium polyneurum at 1 m depth; Sargassum spp., P. japonica, and melobesioidean algae at 5 m depth; and melobesioidean algae at 10 m depth. There was variation among the sites, presumably due to differences in the local conditions.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.42 no.5
• /
• pp.503-508
• /
• 2009

We investigated species composition and variation of benthic marine algae between 2003 and 2006 at Dokdo on the East Sea. The total number of benthic algae species identified was 96, which included 15 Chlorophyta, 30 Phaeophyta, 50 Rhodophyta and 1 Spermatophyta species. The representative species in this study were Ulva pertusa, Caulerpa okamurae, Codium adhaerens, C. frgile, Undaria pinnatifida, Ecklonia cava, Eisenia bicyclis, Dictyopteris undulata, Padina arborescens, Sargassum horneri, Hildenbrandtia rubra, Lithophyllum okamurae, Amphiroa dilatata, Corallina officinalis, C. pilulifera, Prionitis cornea, Grateloupia elliptica, Plocamium telgairiae, Chondrus ocellatus, Chondracanthus intermedia, Chondria crassicaulis, Polysiphonia morrowii, Melobesioidean algae and Phyllospadix sp. Wet weight biomass according to various depths ranged between 1,094.8 to $2,595.3\;g\;m^{-2}$ during the study period. Mean biomass at the investigated sites was greater in the 15m depth range than in the 5 and 10m depths. Vertical distribution was characterized by Ulva intestinalis, U. linza, Endarachne binghamiae, Bangia atropurpurea, Gloiopeltis furcata and Chondria crassicaulis at intertidal zone, Amphiroa dilatata, Corallina pilulifera, Gelidium amansii, Eisenia bicyclis and Ecklonia cava at 2m depth, Ecklonia cava, Eisenia bicyclis, Padina arborescens, Undaria pinnatifida and Sargasum horneri at 5m depth, Ecklonia cava, Sargassum horneri and Padina arborescens at 10m depth, Ecklonia cava, Myagropsis myagroides, Padina arborescens and Sargassum horneri at 15m depth. The R/P, C/P and (R+C)/P value were 1.67, 0.50 and 2.17, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.44 no.3
• /
• pp.298-307
• /
• 2011

The species composition and distributions of subtidal marine algae on the east coast of Korea were studied. We examined all species found in permanent quadrats at three depths (3 m, 5 m and 10 m) at Sacheon between October 2008 and December 2009. Coverage and frequency data were collected monthly via underwater photography and analyzed using a modified photo quadrat method. Of the 82 species identified, 10 were chlorophytes, 21 were phaeophytes, 50 were rhodophytes, and one was a seagrass. The largest number of species (59) was found 10 m deep, while the fewest (39) species were present at 5 m. A total 17 species (two green, five brown, and 10 red algae) occurred at all three depths. The vertical distribution of the study site was characterized by the melobesioidean algae, Ulva pertusa, Sargassum confusum, Phyllospadix iwatensis, and Codium arabicum at 3 m deep, melobesioidean algae and U. pertusa at 5 m deep, and Corallina pilulifera, Prionitis cornea, Chondracanthus tenellus and melobesioidean algae at 10 m deep. Given that coralline algae such as melobesioidean algae and C. pilulifera play important roles in coastal ecosystems, thorough studies on the spatial and temporal variations of coralline algae and the dynamics of marine algal communities on the east coast of Korea are now required.

• ALGAE
• /
• v.23 no.4
• /
• pp.317-326
• /
• 2008

Marine algal flora and community structure were investigated seasonally at three sites in Ilkwang Bay on the southern east coast of Korea from May 2007 to February 2008. Total 103 species including 10 of green algae, 17 of brown algae, 76 of red algae were collected and identified. Among these species, 21 species were found throughout the year. Ulva pertusa, Enteromorpha linza, Grateloupia lanceolata, Chondracanthus intermedia and Caulacanthus ustulatus were distributed dominantly in upper intertidal zone. By contrast, crustose coralline algae, Grateloupia spp., Chondracanthus tenellus, Prionitis cornea and Sargassum spp. occurred predominantly in middle intertidal zone. Grateloupia spp., Sargassum spp., Ecklonia cava and Ulva pertusa were dominant in lower intertidal zone. Annual mean biomass in wet weight was 478.3 g m$^{-2}$. Maximum biomass was recorded in site 1 (731.8 g m$^{-2}$), and minimum was recorded in site 3 (78.5 g m$^{-2}$). The R/P, C/P and (R + C)/P value reflecting flora characteristics were 4.47, 0.59 and 5.06, respectively. Two groups produced by cluster analysis, one including sites 1, 2 and the other including site 3, showed meaningful difference in similarity, each other. Site 3 showed the limited species composition due to inflow of fresh water and absence of solid substratum. However, there was no significant difference between site 1 and site 2. In conclusion, the number of marine algae species and biomass in Ilkwang Bay were markedly reduced comparing with the previous studies. These suggest that a solution for reconstruction of the poor marine algal vegetation is considerably demanded.