• ALGAE
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• 제22권4호
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• pp.305-311
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• 2007

The summer algal flora and community of 15 uninhabited islands in Dochodo, southwestern coast of Korea, were investigated from 9 June to 16 September 2007. A total 53 species (10 green, 14 brown and 29 red algae) of marine algae were identified. Among 15 uninhabited islands, the number of species observed was the highest as 33 species at Jeongdo and Gyeongchido the least as 24 species at Hugdo and Mido. The dominant species were Enteromorpha compressa, Ishige okamurae, Gloiopeltis furcata, Ulva pertusa and Sargassum thunbergii. The algal zonation of intertidal zone was figured out by Gloiopeltis furcata, Caulacanthus okamurae – Ulva pertusa, Sargassum thungergii – Gelidium amansii, Sargassum horneri from upper to lower zone. The flora investigated could be classified into six functional groups such as coarsely branched form (39.6%), filamentous form (25.8%), sheet form (14.1%), thick leathery form (9.9%), jointed calcarious form (5.6%) and crustose form algae (4.9%).

• 한국물환경학회지
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• 제30권5호
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• pp.539-548
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• 2014

This study was carried out to investigate algal community structures and their correlations with environmental factors on five weir areas in the Nakdong River, South Korea. Water qualities, hydrodynamics, meteorological conditions and algal species compositions were observed in studied sites from May 2010 to Dec. 2013. Results showed that average total phosphorus concentration of 2013 was decreased by 52.4% in comparing with that from 2010 to 2011. Chlorophyll.a concentrations were positive significant with water temperature, pH, total phosphorus and total nitrogen, but is not significant with turbidity and suspended solids. Seasonal successions of algae were observed that Stephanodiscus sp. was dominant species with 65.3% of dominant frequency in studied site. Large algal biomass of the low temperature-adapted diatoms were observed during temperature range of $4{\sim}9^{\circ}C$, but large cyanobacterial biomass mainly during high temperature period ranged from $22^{\circ}C$ to $32^{\circ}C$. Microcystis sp. dominated during high water temperature in summer. The yearly correlations of algal biomass with accumulated solar radiations were not significant but seasonal correlations of summer from June to August were significant with correlation coefficient 0.33 (p<0.05). There were not significant correlations between turbidities and algal biomass. Turbidity and suspended solids concentrations were not significant correlation with algal biomass. According to the results, algal communities had strong correlation with water temperature and had partially correlation with solar radiation. For an effective management of algal blooms, water managers should survey with more long-term monitoring of various environmental factors and algal communities.

• ALGAE
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• 제18권4호
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• pp.301-309
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• 2003

Community structure and vertical distribution of benthic marine algae were investigated in the intertidal and subtidal rocky shore of Samyang, Jejudo Island. The total number of 62 algal species composed of 6 Cyanophyta, 6 Chlorophyta, 19 Phaeophyta, and 31 Rhodophyta were observed. The dominant species were melobesioidean algae, Sargassum thunbergii, Hizikia fusiformis, and Ulva pertusa in the intertidal zone and melobesioidean algae, Ulva pertusa, Corallina spp., and Undaria pinnatifida in the subtidal zone. The vertical algal distribution was represented by the melobesioidean algae in the whole rocky shore, Caulacanthus ustulatus in the upper intertidal zone, Sargassum thunbergii and Hizikia fusiformis in the middle and lower zone, Ulva pertusa in the lower zone and Ulva pertusa, Corallina spp., and Undaria prinnatifida in the subtidal zone. The composition of dominant species and pattern of the vertical distribution of algae in the present study were significantly different from the previous reports. Especially, distribution of crustose coralline algae was significantly extended.

• ALGAE
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• 제19권4호
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• pp.339-347
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• 2004

Seaweed community of the sub tidal rocky habitats along the coast of Geumo Archipelago in the central South Sea of Korea is described. This area is characterized by archipelago in which islets are separated by shallow bottom sediments (primary, muddy sand), and turbidity is generally high due to the resuspension of bottom sediments. The hard substrata available for algal attachment are limited to less than 10 m in depth. Thirty sites were randomly chosen along the coast from August 2003 to September 2003 and a 50 m long transect was established at each site. The transect began at a depth of 1 m and ended at the depth of 9 m. The percent cover of all species other than crustose coralline algae was estimated at 2 m depth intervals along the transect using a 0.25 m$^2$ PVC quadrat with 25 squares. Thirty-six species were identified including 6 Chlorophyta, 10 Phaeophyta and 20 Rhodophyta. Species with more than 5% mean bottom cover were Gelidium amansii, Corallina pilulifera, Amphiroa dilatata and Carpopeltis cornea, which formed dense turf-forming algal assemblages at 1-5 m depth. At all sites except S11-S15 located in the western coast of Sorido, bottom covers of seaweed species at the depth deeper than 7 m were less than 6%. The lower limit of algal assemblages was 9 m in depth. We speculate that the limited water clarity and vertical extent of hard substrata available for the settlement of seaweed species are the direct cause of reducing the diversity, abundance and distributional extent of algal assemblages in the area.

• 한국수산과학회지
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• 제40권4호
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• pp.210-219
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• 2007

The benthic marine algal flora and community structure were examined at five sites of the Taean Peninsula, Korea, during July-August 2005. Ninety-six algal species were Identified, including 14 green, 21 brown, and 60 red algae, and 1 marine plant. The common species that occurred at the five sites were Sargassum thunbergii, Gelidium divaricatum, Caulacanthus okamurae, Gracilavia vermiculophylla, and Neorhodomela aculeata. Sthunbergii was the dominant species in terms of coverage and biomass at ail of the study sites. The average biomass varied from $23.72g/m^2$ in dry weight at Chaeseokpo to $66.43g/m^2$ at Padori. The species could be divided into six functional groups in terms of morphological characteristics: 41 coarsely branched forms, 25 filamentous forms, 16 sheet forms, 7 thick leathery forms, including the marine plant Phyllospadix iwatensis, 4 crustose forms, and 3 Jointed calcareous forms. The seaweed communities at the five study sites were unstable and the environmental conditions were bad or very bad. Among the five study sites, the ecological evaluation index (EEI) and diversity index (H') were maximal at Padori at 2.29 and 1.98, respectively. By contrast, the dominance index (DI) was minimal at Padori (0.55) and maximal at Baramarae (0.96). Therefore, we conclude that the rocky shore at Padori has the best environment among the five study sites, although the species richness and biomass of seaweeds have declined continuously over the last 10 years.

• 한국수산과학회지
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• 제44권6호
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• pp.732-739
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• 2011

Marine algal flora and community structure were examined at four sites at Tongyeong, Korea, from February to December 2009. Eighty-two algal species were identified, including 10 green, 25 brown, and 47 red algae. During the study period, the number of species was highest at the Dukpo (61 species) site followed by the Gajodo (60 species), Yepo (58 species), and Chilchundo (53 species) sites. Seaweed biomass ranged from 578.11 to 678.26 g, with the maximum and minimum at Chilchundo and Yepo, respectively. Dominant species in term of biomass were Sargassum thunbergii at Yepo, Dukpo, and Gajodo and Gelidium amansii at Chilchundo. The vertical distribution from the high to low intertidal zone was Sargassum thunbergii and Chondria crassicaulis; Sargassum thunbergii and Ulva linza; Ulva pertusa, Sargassum fulvellum, and Gelidium amansii. Two groups clearly segregated in a cluster analysis, a Yepo/Dukpo group (group A) and a Gajodo/Chilchundo (B), indicating relatively strong differences in similarity. The seaweed community structure of group A was characterized by higher biomass and higher species richness of brown algae than were observed in group B. Additionally, the biomass ratio and the species richness of green algae was lower in group A. These differences in seaweed community structure may have been resulted from the effects of cold effluents.

• 한국수산과학회지
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• 제48권1호
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• pp.82-87
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• 2015

For the ecological evaluation of marine algal vegetation, flora and their communities were surveyed seasonally at Goseong, on the southern coast of Korea. A total of 102 algal species, comprising 17 green, 18 brown and 67 red algae, was identified. Representative dominant species were assessed as Ulva australis, Sargassum thunbergii, and Gelidium amansii. Of these, Ulva australis was remarkably dominant in all seasons. High biomass of the dominant species were recorded. The total seasonal biomass was highest in winter and lowest in summer. The mean biomass value was $1315.6g/m^2$ across the four seasons. Each species was classified into six functional groups, and two ecological state groups (ESG) were evaluated based on these groups. While ESG I, the late successional species group, formed only 18.6% of the algal community; ESG II, composed of opportunistic species, comprised 81.4%. This suggests that environmental stress has been continuously imposed on the marine algal vegetation of the present study area.

• 환경생물
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• 제27권3호
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• pp.252-260
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• 2009

The summer algal flora and community of 9 islands in Dadohae National Park, southwestern coast of Korea, were investigated from June to September 2008. A total of 81 species (13 green, 22 brown and 46 red algae) of marine algae were identified. Among 9 islands, the number of species observed was the highest as 65 species at Jindo and the least as 37 species at Hongdo. The dominant species were Enteromorpha compressa, Ulva pertusa, Sargassum thunbergii, Gelidium amansii, Caulacanthus okamurae, Gloiopeltis furcata, and Symphyocladia latiuscula. The algal zonation of intertidal zone was figured out by Gloiopeltis furcata, Ishige okamurae, Caulacanthus okamurae-Enteromorpha compressa, Sargassum thungergii-Gelidium amansii, Symphyocladia latiuscula from upper to lower zone. The flora investigated could be classified into six functional groups such as coarsely branched form (38.1%), filamentous form (24.7%), sheet form (11.3%), thick leathery form (13.9%), jointed calcarious form (6.3%) and crustose form algae (5.7%). R/P and (R+C)/P values were 2.2 and 2.8, respectively. A cluster analysis of species occurrence was suggested that the number of marine algal species was different from greatly among the sampling sites.

• 대한환경공학회지
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• 제33권5호
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• pp.314-324
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• 2011

하수를 이용해서 배양된 조류는 바이오디젤 생산에 유용한 자원이다. 그러나 실제 하수에서 조류의 영양염류 신진대사와 하수 세균과의 상호작용에 관한 연구는 미흡하다. 본 연구에서는 하수로 배양되는 대표적 조류균주인 Ankistrodesmus gracilis SAG 278-2에 의한 하수 내 질소, 인 제거 거동을 평가하였고, 조류와 상호작용하는 하수 내의 세균 군집을 분석하였다. 하수 슬러지 세균 군집과 비교하였을 때, 조류-세균 복합 군집은 하수 내보다 높은 영양염류 제거를 보였다. 16S rRNA 유전자 분석 결과, 조류-세균 군집에서 조류가 성장함에 따라 Unclassified Alcaligenaceae 세균이 선택적으로 우점됨을 알 수 있었고, 조류에 의해서 선택적으로 우점화된 하수세균은 자연 수질 환경에서 조류와 공생적으로 상호작용 하는 것으로 알려진 Alcaligenes faecalis subsp. 5659-H와 계통학적으로 가까운 것으로 밝혀졌다. 본 연구의 결과, 하수 내의 높은 영양염류 제거를 보이는 조류-세균 복합 군집에서의 조류의 성장 및 신진대사가 특정 세균의 분포에 영향을 주는 것을 알 수 있었다.

• 생태와환경
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• 제37권4호통권109호
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• pp.368-372
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• 2004

1980년대 이래로 Biwa호 북측 지역 연안대에서 초여름 동안 Spjrozyra에 의해 조성된 저서 사상성 부착녹조류 군집의 발달이 관찰되어 왔다. 이들의 발달은 초여름 저서 조류 군집의 생물량 증가와 생물량의 계적적 변동 양상에 영향을 미친 것으로 판단된다. 본 논문에서는 Spjrozyra 군집 발달의 원인을 1963-64년, 1995-96년, 2001-02년 동안 수행된 연구 결과(특히,영양염,$NO_3^--N$)에기초하여 고찰하였다. 6월 동안의 $NO_3^--N$의 농도는 1964년 6월에 $20{\mu}g\;L^{-1}$에 비교할 때 1995년과 2002년은 $100{\mu}g\;L^{-1}$ 이상이었다. 이 결과는 $NO_3^--N$가 1963년도에 Spjrogyra 성장에 대해 제한요인으로 작용하였음을 시사한다. Biwa호 북측 지역 개방수역에서 $NO_3^--N$의 농도는 1950년대이후 유역에서의 인구증가와 경제성장의 영향으로 뚜렷하게 증가하였다. 따라서 Biwa호에서 Spjrogyra 군집의 발달은 인간활동에 의한 영양염 공급의 증가의 결과로 추정된다.