• Journal of Microbiology and Biotechnology
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• v.24 no.8
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• pp.1123-1132
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• 2014

This study evaluated the growth and nutrient removal ability of an indigenous algal consortium on real untreated municipal wastewater in a high rate algal pond (HRAP). The HRAP was operated semicontinuously under different hydraulic retention times (HRT: 2, 4, 6, and 8 days). The average removal efficiencies of chemical oxygen demand, and total nitrogen and phosphate of real municipal wastewater were maintained at $85.44{\pm}5.10%$, $92.74{\pm}5.82%$, and $82.85{\pm}8.63%$, respectively, in 2 day HRT. Algae dominated the consortium and showed high settling efficiency (99%), and biomass and lipid productivity of $0.50{\pm}0.03g/l/day$ and $0.103{\pm}0.0083g/l/day$ (2day HRT), respectively. Fatty acid methyl ester analysis revealed a predominance of palmitate (C16:0), palmitoleate (C16:1), linoleate (C18:2), and linolenate (C18:3). Microalgal diversity analyses determined the presence of Chlorella, Scenedesmus, and Stigeoclonium as the dominant microalgae. The algal consortium provides significant value not only in terms of energy savings and nutrient removal but also because of its bioenergy potential as indicated by the lipid content (20-23%) and FAME profiling.

• Journal of Plant Biology
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• v.26 no.4
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• pp.181-190
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• 1983

Seasonal occurrence of benthic algae and changes of subtidal vegetation were studied for their species composition, diversity and biomass during 1982 and 1983 at several selected sites at Juckdo Island (38$^{\circ}$12'N, 128$^{\circ}$32'E), eastern coast of Korea. Three large brown algae which played a role in change of algal vegetation through their great biomass were investigated with regard to their seasonal growth. Large brown algae such as Undaria pinnatifida, Costaria costata, Laminaria japonica, Agarum cribrosum, Sargassum confusum and S. hornerii constitute the major portion of vegetation in this area throughout the year. Algal vegetation in spring time is characterized by dominance of species U. pinnatifida and C. costata, whereas the summer vegetation by S. confusum and S. hornerii. In autumn large brown algae are shedded and only small algae, such as Chondrus ocellatus and Grateloupia filicina, remain. The vegetation in winter is dominated by the growth of U. pinnatifida and C. costata. Monthly changes in mean length and weight of randomly collected U. pinnatifida, C. costata and S. confusum are as follows; U. pinnatifida occurs from December to June and shows their maximum growth during March (120 cm in length, 201 g/individual in wet weight), its maximum growth rate is 1.4 cm/day, 3.3 g/day in this month. The growth season of C. costata is very similar to U.pinnatifida, but their average maximum length(110 cm) and weight (106 g/ind.) are lower than U. pinnatifida. The greatest growth rate is during March (1.8 cm/day, 2.0g/day). S. confusum is present throughout the year and reaches the maximum growth (102 cm, 63g/ind.) in July. Maximum growth rate (1.5 cm/day, 1.2 g/day) occurs also during this month. U. pinnatifida and C. costata show different months of maximum growth evidently during the two year. This seems to be caused by a considerable damage to the local vegetation followed by heavy storm in February 1983.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.2
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• pp.612-625
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• 2017

To grasp the algal vegetation using the occurred species number, biomass and dominant species, this study was performed in the subtidal zone of Muan-gun, in the intertidal zone of Jindo-gun and in the intertidal zone and subtidal zone of Geomundo, the south-eastern coast of Jeollanamdo, Korea in the spring 2014. The total occurred species was 140 ones including 10 chlorophytes(7.14%), 54 phaeophytes(38.57%) and 76 rhodophytes(54.29%); the biomass was $70,484g{\cdot}w{\cdot}w/m^2$ in total. The flora charateristic using R/P ratio, geographical distribution pattern of algae, at the Station 9-1(intertidal zone) in Geomundo was tropical; the flora at the Station 6 (Maengseong-ri, Sanjodo, Jindo-gun) and the Station 9-2(subtidal zone) in Geomundo were mixed; the others were arctic to temperate. The physiognomic types were also shown. Each species was classified into six functional-form groups, and two ecological state groups(ESG) were evaluated based on these groups. The coarsely branched-group of functional-form groups was 44% of total occurred species. The ESG II in all study sites was high, and this is maybe due to the environmental stress such as pollution and disturbance, etc.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.607-618
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• 2013

Marine macroalgal community structures and characteristics of ocean environmental factors were examined seasonally at four sites in Jeju Island, Korea, from March to November 2012. A total of 71 macroalgal species were identified, including 9 green, 7 brown, and 55 red algae. Peyssonnelia capensis occurred at all study sites and in all seasons. The average annual biomass of seaweed was 991.84 g wet $wt/m^2$, with seasonal variations from 543.80 g in autumn to 1,284.17 $g/m^2$ in summer. A green alga, Codium coactum, was the dominant species, occupying 21.31% (211.39 $g/m^2$) of the total algal biomass in Jeju Island. Subdominant species were Ecklonia cava and Lithophyllum okamurae, comprising 20.85% (206.75 $g/m^2$) and 19.64% (194.75 $g/m^2$), respectively, of the total algal biomass in Jeju Island. The vertical distribution of subtidal seaweeds was represented by L. okamurae at 5 m depth, C. coactum at 10 m depth, E. cava at 5-10 m depth and P. capensis at the 20 m depth level. In the present study, crustose coralline algae, which predominated on barren ground, were subdominant species at all study sites. Community indices varied between 0.51-0.63 for dominance index (DI), 5.53-8.14 for richness index (R), 0.51-0.63 for evenness index (J'), and 2.04-2.32 for diversity index (H'). On the basis of seaweed biomass and community indices, Sinchang was the best preserved coastal area, showing maximal values in biomass, and evenness- and diversity-indices, and minimal value in the dominance index, representing stable environmental conditions. In contrast, the Onpyung and Topyeong sites, located near tourist venues such as Udo and Seogwipo were relatively poor habitats based on community indices and biomass. The present results could imply that climate changes alter seaweed community structure, and long-term monitoring of the study sites is required.

• ALGAE
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• v.23 no.4
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• pp.301-310
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• 2008

The marine benthic algal flora and biomass of Chuja Island, southern coast of Korea, was investigated. The collections of intertidal marine algae were made at two sites, Yecho of Hachujado and Hupo of Sangchujado, from October 2006 to July 2007. A total of 162 species, including 15 green, 47 brown and 100 red algae, were identified in this study. The occurrence of species according to season was abundant during spring to summer and less in autumn. The vertical distribution of intertidal zone in Chujado was characterized by Gloiopeltis spp., Myelophycus simplex, Ishige okamurae, Chondrus ocellatus, Grateloupia elliptica, Hizikia fusiformis and Sargassum spp. The average biomass of macroalgae was measured as 400 g wet wt m$^{-2}$. The dominant species based on the biomass were Sargassum yezoense, S. coreanum and Hizikia fusiformis. ESG II (ecological state group) as an opportunistic species, including sheet form, filamentous form, and coarsely branched form, occurred 85.8% in the intertidal seaweeds. These results provide a baseline for future monitoring studies in the Chuja Island.

• ALGAE
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• v.23 no.4
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• pp.295-300
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• 2008

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.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.1
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• pp.70-75
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• 1986

The population and kinds of algae causing the waterbloom on the rice seedling bed and the damage of young rice plant by the nuisance green phytoplanktonic algae in rice field were studied to find out the efficiency of fertilizers and the effect of methods of fertilizers application in the rice field, laboratory, pot and green house. pot and green house. The results obtained were summarized as follows; 1. In the rice seedling bed, the kinds of algae causing waterblooms were identified mainly photosynthetic bluegreen algae as the Anabaena, Ulothrix and Oscillatoria spp. in reclaimed saline soil. Micromonospora, Oscillatoria, and Chlamydomonas spp. were habitated mainly in plain. Whereas, Spyrogyra, Oscillatoria and Navicula spp. were identified mainly in mauntainous area. 2. In the rice field, the nuisance phytoplanktonic green algae were identified mainly Scenedesmus, Chlamidospora, and Micromonospora spp. in Gimjae plain, in Namweon mountainous area and Gangjin costal plain, respectively. 3. The algal biomass has been havily habitated in which rice field were constituted with high pH value and high concentration of $NH^+_4-N$ and $NO^-_3-N$ in surface water and in soil with the optimum temperature for the algal growth ($22-30^{\circ}C$). 4. In the laboratory experiment, maximum algal biomass were obtained at levels of 80 ppm for the nitrogen and 20 ppm for the phosphorus. And were obtained of the levels of 40 ppm in the case of joint application of N and $P_2O_5$. 5. From the pot experiment, compare of the control plot, an addition of nitrogen alone or nitrogen+phosphorus enhanced algal biomass while the phosphorus alone did not. 6. Surface application of fertilizer was remarkably increased of algal biomass than did the whole layer or deep layer application.

• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.432-438
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• 2018

Microalgae hold promise as a renewable energy source for the production of biofuel, as they can convert light energy into chemical energy through photosynthesis. However, cost-efficient harvest of microalgae remains a major challenge to commercial-scale algal biofuel production. We first investigated the potential of electrolytic water as a flocculant for harvesting Tetraselmis sp. Alkaline electrolyzed water (AEW) is produced at the cathode through water electrolysis. It contains mineral ions such as $Na^+$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ that can act as flocculants. The flocculation activity with AEW was evaluated via culture density, AEW concentration, medium pH, settling time, and ionic strength analyses. The flocculation efficiency was 88.7% at 20% AEW (pH 8, 10 min) with a biomass concentration of 2 g/l. The initial biomass concentration and medium pH had significant influences on the flocculation activity of AEW. A viability test of flocculated microalgal cells was conducted using Evans blue stain, and the cells appeared intact. Furthermore, the growth rate of Tetraselmis sp. in recycled flocculation medium was similar to the growth rate in fresh F/2 medium. Our results suggested that AEW flocculation could be a very useful and affordable methodology for fresh biomass harvesting with environmentally friendly easy operation in part of the algal biofuel production process.

• ALGAE
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• v.23 no.2
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• pp.151-162
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• 2008

Marine algal flora and community structure were seasonally examined at three sites in the vicinity of the Wolseong nuclear power plant in Korea from February to November 2006. A total of 126 seaweeds including 25 green, 31 brown, 70 red algae, and 1 marine plant were identified. The greatest number of species occurred at Jeonchonri (101 species) followed by intake (88 species) and discharge (29 species) during the study period. Of 126 seaweeds, 76 annuals and 13 warm tolerance species were recorded. Dominant species based on important value (IV > 10) were Ulva pertusa and Enteromorpha linza at intake, U. pertusa and Padina arborescens at discharge, and Sargassum horneri and Corallina pilulifera at Jeonchonri shore. Annual average biomass exhibited a wide range of variations, from 40.67g m-2 in dry weight at discharge to 133.69g m-2 at Jeonchonri. Among six functional groups, dominant group was coarsely-branched form at intake and Jeonchonri, but it was different at discharge site as filamentous form. Seaweed community structures of discharge site were distinguishable in decreasing species richness, biomass, species diversity index (H’), richness index (R), and evenness index (J’). Also, the ratios of green algae, warm tolerance species, annual algae, filamentous form and dominance index (DI) remarkably increased. Such phenomenons of discharge site are usually found under environmentally stressful conditions such as high disturbance. Thus, I can conclude that the heated effluents of nuclear power plant act as environmental stress influencing seaweed community structures and it can be detected with various community indices.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.3
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• pp.385-392
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• 2016

Seasonal variability in the algal community structure of intertidal zones was examined at six study sites in Marine National Parks, on the western and southern coasts of Korea from March to November 2015. A total of 193 species of algae, comprising 27 green, 40 brown and 126 red algae, were identified. Algal biomass averaged 101.50 g dry wt./m² with a maximal at Tonggae (168.12 g dry wt./m²) and minimum at Haseom (54.49 g dry wt./m²). The dominant seaweeds by biomass were Sargassum thunbergii at five sites (Tonggae, Haseom, Namdongri, Ando amd Sinjeonri), and S. fusiforme at Soando. Community indices measured as follows: dominance index (DI), 0.31–0.69; richness index (R), 7.30–11.43; evenness index (J'), 0.33–0.49; and diversity index (H'), 1.15–1.86. As evaluated using community indices and environmental states, the EEI (Ecological Evaluation Index) of the Marine National Park was “normal”. The present results indicate that seaweed community structures and indices could be used to evaluate the environmental status of coastal ecosystems.