• ALGAE
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• 제21권3호
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• pp.305-310
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• 2006

Succession of artificial seaweed communities in an artificial iron reef at Ikata, southern Japan was studied based on monthly or bimonthly observations from February 1999 to August 2000. Communities were associated with different substrata (40 cm x 60 cm: steel, concrete, wood and stone) as the cover on artificial iron reefs (4.5 m x 4.1 m x 2.5 m, 45.38 m3 and 3.2 ton), which were placed on a sandy substratum at 8 m depth. Within one month diatoms dominated on all substrata with cover of approximately 100%. Enteromorpha intestinalis and Colpomenia sinuosa dominated on the reef within three months after the placement in the spring. Seaweed communities on the reef decreased during the summer. In the winter, the seaweeds on the reef recovered. Sargassum spp., Ecklonia kurome and Padina arborescens dominated on each substratum after one year. Seaweed communities on the artificial reef were similar to those on the rocky substratum around the artificial reef and also similar on different substrata covering the iron artificial reef. These results indicate that seaweed succession was impacted by season and the recruitment of spores and propagules from mature algae around the artificial reefs.

• ALGAE
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• 제21권3호
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• pp.295-305
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• 2006

The purpose of the study is to understand the ecological characteristics of the early stage of community formation of epilithic diatoms. The samples were daily collected from a site of the Kumho River during 70 days from October 13 to December 21 in 2002. Total 126 diatom taxa collected in the study were classified into 114 species and 12 varieties belonging to 26 genera. About 80% of the taxa collected from the artificial substrata during the whole studying period were observed until tenth day from the start time of the study. In the study the successional process of the diatom community was divided into the three stages of the early, the middle and the later by cluster analysis based on the similarities in species composition among the communities. Cocconeis placentula Ehrenb. and C. placentula var. lineata (Ehrenb.) V.H., horizontally positioned species, would be divided into the early successional species, and Diatoma vulgre Bory, vertically positioned species, was the later successional species. Cell densities and species composition of the diatoms on the artificial substrata were closely similar to them of natural substrata after 40th day from the start time of the study.

• ALGAE
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• 제19권2호
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• pp.115-122
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• 2004

The epilithic algal communities on the artificial substrata (unglazed ceramic tiles) were investigated from 5th July to 24th July 1999 with two or three days intervals for elucidating the effects of the experimental acidification. They were harvested inside the mesocosm with and without the acid treatment on Togyo reservoir within the Civilian Passage Restriction Line near Demilitarized Zone (DMZ) in Korea. After the colonization of epilithic algal community, their standing crops revealed different patterns outside and inside the mesocosm. However the time lapse of 5 days was observed on the inside with acid treatment. The dominant species were different: Achnanthes minutissima was outside but Coenochloris polycocca was inside and inside with acid treatment. The differences in floral composition were also found. Achnanthes minutissima which has been the most important species in the colonization by the epilithic algal community of the mesocosm was less important at the lower pH. Coenochloris polycocca is a species well adapted to low pH.

• 한국환경과학회지
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• 제7권1호
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• pp.112-115
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• 1998

During the spring and fall of 1994 and winter of 1995, the exposure time of periphyton biomass on terval. In the streams with low periphyton biomass (chi. a: 2-4 mg/$m^2$) in natural rocks, biomass of arttificial substrata (unglazed tile: $3.7{\times}9.5{\times}2 cm$) exceeded that of the natural rocks after 28 days, while sites with high biomass (chi. a: 20-60 mg/$m^2$) in natural rocks showed slower biomass accumulation after 40 days. Due to the high licht input and temperature in a Partially shaded mountain stream, development of periphyton biomass in spring occurred faster than that of winter. In general, development of periphyton biomass placed on artificial substrata took 4-5 weeks in spring and at least 6 weeks In winter to reach the natural level.

• Ocean and Polar Research
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• 제23권3호
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• pp.255-264
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• 2001

Development process of benthic community on experimental substrata attached on a newly installed artificial reef complex in Jeju Island was observed for 27 months from 1992 to 1994. Among 34 species of algae and 64 species of zoobenthos obtained from the study, Ecklonia cava dominated with a maximum biomass of about $10kg/m^2$. It was able to smother the other animals, however it provided a new substrate for the new settlers. Opportunistic bryzoans such as Likenopora radiata and Dexiospira spirillum occurred during the early stage were substituted by poriferans, banacles and other bryzoans. Young barnacles were smothered by bryozoans, on the contrary, bryozoans were bulldozed by adult barnacles. No apparent differences have been observed between vertically and horizontally installed substrates in terms of species composition and biomass during the early stage of succession. Thereafter owing to the rapid growth of E. cava, the horizontal substrata carried on a higher biomass while the vertical showed a higher coverage. The benthic process on the experimental substrata can be classified into three stages: initial stage, build up stage and regulatory stage. Important mechanisms involved were canopying of E. cava, suffocation by bryozoans and poriferans, and bulldozing of adult barnacles.

• Fisheries and Aquatic Sciences
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• 제3권1호
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• pp.1-7
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• 2000

Different substrata fixed as the roof (for shadow) on artificial iron reef had been developed as a tool for valuable fishery resources. The experiment was set up on a sandy bottom substratum at 8m depth in Muronohana, Ikata, Japan. Within one month of placement of the plates, diatoms dominated the experimental plates with a coverage of $100\%$ approximately. Enteromorpha intestinalis and Colpomenia sinuosa dominated within three months after the placement. E. intestinalis coverage on substrata was estimated $7\%$ on the plate shaped iron bar, $12-14\%$ on concrete plates, $18\%$ on the plate fixed pebble, $61\%$ on the plate to accumulated wood, and 80-100% on the steel materials plate. Whereas after four months of placement, C. sinuosa coverage on plates became $1-36\%$ on different plates, and $100\%$ on the plate to accumulated wood. The differences in E. intestinalis and C. sinuosa colonization on the different substrata were probably due to variations in their surface roughness influencing the settlement of zoospores, and thus gametophyte. development. After five months of placement, the above two species slowly disappeared.

• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2004년도 학술대회
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• pp.31-31
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• 2004

• ALGAE
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• 제19권2호
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• pp.107-114
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• 2004

Patterns of epilithic algal colonization on artificial substrata (unglazed ceramic tiles) were investigated from 23rd April to 3rd July 1999 at weekly intervals over a 10 weeks period outside and inside the mesocosm in Togyo reservoir within the Civilian Passage Restriction Line near Demilitarized Zone (DMZ) in Korea. The highest standing crops of epilithic algae was 1,798$\cdot$10³ cells$\cdot$$cm^{-2}$ outside the mesocosm on 26th June and also inside the mesocosm those was 2,391$\cdot$10³ cells$\cdot$$cm^{-2}$ on 26th June, 9 weeks after the experiment began. The dominants outside the mesocosm were Achnanthes minutissima, Navicula bicephala, Oscillatoria angusta, Synedra delicastissima, S. tenuissima, S. ulna v. danica and Tabellaria flocculosa, and those inside the mesocosm were Achnanthes minitissima, Coenochloris polycocca, Fragilaria crotonenesis, Peridinium cinctum, Synedra delicatissima, Tabellaria flocculosa and Ulothrix subtilissima. Diatoms were most abundant and Achnanthes minutissima was the most important species colonizing on the tiles. Chlorophyll-a content was highest value of 5.4 mg$\cdot$$m^{-2}$ on 19th June after 8 weeks growth outside the mesocosm and was 24.4 mg$\cdot$$m^{-2}$ on 26th June, 9 weeks after the experiment began on tiles inside the mesocosm. It was also shown that unglazed ceramic tiles were a more suitable substratum for colonization than the glass slides. Consequently the substratum selection plays an important role in the colonization by the epilithic algal community.

• 한국해양학회지
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• 제22권4호
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• pp.257-270
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• 1987

1982-1983년 진해항 및 마산만에서 발달하는 부착생물 군집을 슬라이드 글라스 및 浸漬基板실험에 의하여 연구하였다. 15일의 침적실험후 세균의 개체수는 1.7$\times$$10^{4}$CFU/$cm^{2}$로 산출되었고, 微小生物群集에서 발달한 저생 규조류 는 총 46분류군이었다. 부착생물군집의 順次的 변화과정을 명백히 볼 수 있었고, 우 점 규조류 종은 Licmophora flavellata, Navicula grevillei, 및 Nitzschia closterium 로 나타났다. 대형생물군집의 주요 종은 Mytilus edulis, Balanus amphitrite mphitrite, Hydroides ezoensis및Celleporina sp. 로서 5개월의 침적후에 500g/100cm $^{2}$이상의 생물량을 보였다. 두 조사해역에서의 군집발달양상이 큰 차이를 보이 는데 이는 주로 주변수의 물리화학적 안정성 및 영양상태에 기인하는 것으로 판단 된다. 부착생물군집의 발달과정은 유생의 생성시기 및 성장률에 매우 큰 영향을 받 는 것으로 밝혀졌고, 군집발달의 전 과정은 다음과 같이 요약이 된다. 세균 및 규조류-다세포해조류-따개비류, 홍합류 및 다모류-해면류, 말미잘류 및 해초류.