• ALGAE
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• v.19 no.4
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• pp.311-320
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• 2004

A great portion of the marginal zone in Lake Gocheonam was covered with reed plants. Algae attached to the reed stems were exclusively composed of diatoms. Sixty-six species of diatoms were encountered in a floral survey. The important species were Nitzschia liebetruthii Rabh., Nitzschia acicularis (Ku¨tz.) W. Sm., Navicula gregaria Donk., Cocconeis placentula var. lineata (Ehr.) V.H. etc. Among the diatom flora, six species - Navicula nivalis Ehr., Navicula recens Lange-B., Nitzschia angustatula Lange-B., Nitzschia compressa (Bail.) Boyer, Nitzschia lanceola var. minutula Grin. and Surirella crumena Bre´b. - were recorded in Korea for the first times. Life forms of the reed-attached diatoms were simply prostrate. The biomass of epiphytic algae ranged from 0.05㎍ chl-$\alpha$ cm$^{-2}$ to 2.32$\mu$g chl-$\alpha$ cm$^{-2}$. The algal biomass of dead stems was higher than that of the living stems, and their flora were rich. The algal biomass reached a maximum in the spring after the death of the reed plants. The reed plants exhibited rich diatom flora and significantly high algal biomass on their stems to have taxonomical and ecological importance in the freshwater.

• ALGAE
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• v.23 no.1
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• pp.75-81
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• 2008

The epiphytic diatom flora living on leaf tissues of Zostera marina, Z. japonica and Z. caespitosa at three study sites (Dadae, Gabae, and Jangmok) located in Geoje Island has been examined from July 2001 to March 2002 bimonthly. Total 81 species in 26 genera of diatoms have been observed on leaf tissues of the 3 Zostera species throughout the present study. Cocconeis spp. were predominant on Z. japonica, whereas Navicula spp. and Nitzschia spp. were predominant on Z. marina and Z. caespitosa. The community structure of the diatom assemblages varied according to the seagrass species. Species compositions of epiphytic diatoms appear to be closely related to morphology and lifespan of seagrasses.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.3
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• pp.173-177
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• 2009

A total of 3 epiphytic macroalgae were collected from eelgrass bed in Jindong Bay, and Scytosiphon lomentaria and Colpomenia sp. in Phaephyta, Gracilaria sp. in Rhodophyta occurred during study periods. For epiphytic microalgae (diatoms), Cocconeis scutellum and Cocconeis placentula were common species. Seasonal variations of epiphytic algal biomass were marked: the higher epiphytic macroalgae was 3.3 g $DW/m^2$ in November 2003; whereas epiphytic diatoms were 43,153 $cells/m^2$ in June 2003. Diversity and number of epiphytic macroalgae species were the lowest in the study area, compared with those of in other areas such as Koongyang Bay, Dongdae Bay, and Aenggang Bay. These results were therefore likely due to the severe physical characteristics of the intertidal mudflat eelgrass biological characteristics, and the deterioration of water quality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.1
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• pp.79-88
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• 1991

To study the distribution patterns of epiphytic diatom on Porphyra species and ambient water phytoplankton, samples were collected in the Gaeya Island, Kyukpo, and Mokpo of the Yellow Sea from February 1989 to March 1990. Foully species of epiphytic diatoms were observed. Of these, the dominant species of epiphytic diatoms are Limophora dalmatica, L. abbreviata, Melosira nummuloides, Paralia sulcata, Achnanthes javanica var, subconstricta, Grammatophora oceanica, Navicula sp., Synedra sp., Pinnularia sp., Fragilaria striatula, Cocconeis scutellum var. parva. Licmophora dalmatica predominated troughout the study period. Phytoplankton standing stocks were relatively larger than those of other coastal areas in the Yellow Sea, Korea. Distribution patterns of epiphytic diatoms and the ambient water phytoplankton in Gaeya Island were similar to those of Kyukpo, but different from Mokpo.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.4
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• pp.184-191
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• 2010

Epiphytic diatoms are very important organisms in the seagrass ecosystem because their colonization on leaves increases microtopography and provides attachment sites that make the leaves more hospitable for other epiphytes. Epiphytic diatoms were attached to the leaves in the following 3 manners: (1) parallel to the cells of the seagrass leaf or by molding the shape of the diatom along the cell shape of the leaf; (2) with increasing diatom density toward the leaf tip; (3) Cocconeis species as attaching species than the Naviculoid species as the second attaching species on the leaf tip. In addition, the epiphytic diatom communities on Zostera marina leaves differed from those on the Zostera japonica leaves, but were very similar to the epiphytic communities on Zostera caespitosa leaves. Our results suggest that the epiphytic community on seagrass leaves varied according to the leaf shape such as leaf length and width, but the leaf cell shape or size did not influence the dynamics of the diatom communities.

• Korean Journal of Ecology and Environment
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• v.42 no.1
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• pp.95-106
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• 2009

The Shihwa constructed wetland was established for the treatment of severely poluted water from Banwoul, Donghwa and Samhwa streams. This study was focused on investigating the structure of epiphytic diatom communities on reed (Phragmites communis) planting area at Banwoul high wetland (3 stations) and low wetland (3 stations) from March to October 2005. The concentration of T-N of inlet stations from the streams were decreased by flowed through the wetland, but the concentration of T-P were increased at outflow part. Epiphytic diatoms on the reed were a total 109 taxa which were composed of 103 species, 5 varieties, 1 unidentified species. The standing crops were rapidly decreasing tendency from spring to autumn but chlorophyll-a concentration were showed a very irregulated changes. Dominant species were 6 taxa which were Achnanthes minutissima in the early investigation, and were changed to the genus Navicula and the genus Nitzschia in the summer. DAIpo were ranged the values of $20.2{\sim}51$, which were mesosaprobic states at the high wetland and ranged the values of $12.4{\sim}52$, which were polysaprobic to mesosaprobic states at the low wetland. TDI were ranged the values of $28.8{\sim}94.5$, which were oligotrophic to eutrophic state at the high wetland and ranged the values of $33.3{\sim}89.7$ which were mesotrophic to eutrophic states at the low wetland. The healthy assessment (DAIpo and TDI) of water ecosystem were showed clean-bad from spring to autumn. These epiphytic diatom communities were determinated by the biological factor such as the growth of reed and the physical factors such as water temperature, light penetration and SS and so on.

• ALGAE
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• v.25 no.2
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• pp.57-64
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• 2010

A variety of Cyclotella atomus were discovered among the epiphytic diatoms on eelgrass (Zostera marina L.) in Korean waters. Cyclotella atomus var. marina has a flat and disc-shaped valve, and is clearly differentiated into a striate marginal zone and a smooth central zone. The valves have a very small diameter ranging from 3.1-3.4 ${\mu}m$. This small diatom does not have any central ornamentation. The marginal striate zone has numerous granules toward the mantle. The valves have five or six marginal fultoportulae with two satellite pores and a single marginal rimoportula.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.362-372
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• 2011

The relationships among total epiphytes, algal epiphytes and eelgrass ($Zostera$ $marina$ L.) were studied at eelgrass medows from July, 1998 to July, 1999 in Yulim-ri, Yeosu, Korea. Epiphytic diatoms on eelgrass leaves were observed from July to December 1998. From the results of this study, we inferred the following three (3) conclusions : 1) As eelgrass grew older, biomass of epiphytes increased, according to relationships between the leaf length and area of eelgrass and biomass (DW, AFDW and Chl. $a$) of epiphytes. 2) According to the ratio of dry weight, ash-free dry weight and Chlorophyll of epiphytes, the algae with calcareous or siliceous skeletons, such as coralline algae or diatoms, were dominated in the epitphytic algae community. 3) The autotrophic index (AI) calculated from AFDW and Chl. $a$ of epiphytes varied from 151 to 375. However, the period of autotrophic community was shorter than heterotrophic community and the value of AI was high. From these results, we inferred that heterotrophic community, including detritus or microorganisms were dominated in the most of research period.

• ALGAE
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• v.18 no.4
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• pp.333-339
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• 2003

To establish a cultivation method of Petalonia fascia, seeds and seedlings cultures and growth tests were performed at the Daeri aquafarm in Haeui, Shinan, Jeollanamdo, Korea. Gametes were easily released from the mature plurilocular sporangia. They developed to crustose discoidal stolons and grew to filamentous and discoidal stolons. The indoor seeding was performed by using the 100-150 ${\mu}m$long fragments of stolons on Porphyra nets and the erect thalli developed from the cuttings when the seawater temperatures were 10-15$^{\circ}C$. In the experimental cultivation in the sea, 1-2mm long plantlets were found after 15 days of cultivation; after two months thalli grew to their maximal size of 215-355 mm long blades; after three months the length of thalli began to decrease due to distal disintegration and the plant color changed to yellow and epiphytic diatoms were attached on the thalli, which deteriorated the quality of products. The cultivation of P. fascia by the regeneration of filamentous-discoidal complexes was carried out successfully for the first time in Korea.

• Journal of fish pathology
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• v.26 no.3
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• pp.275-282
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• 2013

The use of activating treatment agent (formerly acid treatment agent) has been an effective strategy to remove deleterious epibiont organisms such as diatoms and green seaweeds, and it has greatly contributed to increase in Porphyra production. Although many manufacturers supply many kinds of activating treatment agent with different components in these days, no report about their effects on Porphyra culture was found. In this paper, effects of a commercial activating treatment agent were evaluated for practical use in Porphyra culture. No difference was found in dead cell ratios(%) of Porphyra yezoensis thalli between treated and control groups. However, dead cell ratios of Monostroma nitidum thalli were increased from 0~4.6% to 99.0~100% after the treatment. Bathing Porphyra thalli in activating treatment agent resulted in a great decrease in epiphytic bacterial number attached to the thalli from $10^2{\sim}10^{11}$ cells/g to $0{\sim}10^5$ cells/g but did not change the colour of the thalli. These results suggest that bathing Porphyra thalli in activating treatment agent could be a promising strategy to remove green algae, diatoms and bacteria.