• The Korean Journal of Ecology
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• 제23권4호
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• pp.299-307
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• 2000

To understand the mechanism of phytoplankton succession in the Nakdong River, the resource availability (silica) and grazing effect on the phytoplankton community were investigated in an enclosure experiment at Mulgum in March 1995. In all enclosures, Stephanodiscus hantzchii was dominant during the first week. Two weeks later, the diatom community in the A (river water only) and B (filtered river water) enclosures was shifted to colonial green algae (Actinastrum sp., Pediastrum spp. and Scenedesmus spp.) and nanoplankton (2~3 ${\mu}$m of diameter) due to the silica depletion. In the C (silica addition in river water, 3 mg 1$^{-1}$ week$^{-1}$) and D (silica addition in filtered water) enclosures, Fragilaria crotonensis and Synedra acus increased as the silica addition was continued. The percentage of small phytoplankton (size, 10~13 ${\mu}$m) in the filtered enclosures (B and D) was much higher than that of A and C enclosures. A laboratory bottle experiment conducted in the fall of 1994 also showed similar results. Therefore, it is concluded that silica and zooplankton are important regulators in phytoplankton succession during the diatom blooming season in the Nakdong River.

• ALGAE
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• 제20권1호
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• pp.43-52
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• 2005

A study on the seasonal changes in the phytoplankton community was carried out in four aquaculture ponds of Bangladesh over a period of 16 months from August 2000 to November 2001. Out of 45 phytoplankton species identified, 30 belong to Cyanophyceae, 7 to Chlorophyceae, 5 to Bacillariophyceae and 3 to Euglenophyceae. The highest phytoplankton abundance was observed in spring followed by early autumn, summer, and the lowest was in winter. The annual succession of Cyanophyceae was characterized by spring and early autumn period dominated by Microcystis sp. Anabaena sp. and Planktolymbya sp. with Microcystis sp. as the main blue-green algae represented. Chlorophyceae was characterized by rainy season domination of Chlorella vulgaris, Pediastrum sp. and Scenedesmus denticulatus with maximum abundance of Chlorella vulgaris. Whereas Bacillariophyceae was dominant during the winter period. Navicula angusta and Cyclotella meneghiniana were the most frequently occurring species of Bacillariophyceae throughout the study period. Euglenophyceae was dominant in late autumn and Euglena sp. was the dominant species. The effect of various physicochemical water quality parameters on the seasonal distribution and succession of the above mentioned phytoplankton population as well as the interaction and eutrophication are discussed.

• 한국물환경학회지
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• 제26권4호
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• pp.673-680
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• 2010

Environmental factors and phytoplankton community in Lake Doam were monthly investigated at 3 stations from April 2009 to November 2009. During the study period, the concentrated rainfalls occurred at between July and August and then the TP and turbidity were sharply increased in in-lake. A total of 91 phytoplankton species was classified and these were consisted of 38 Bacillariophyceae, 35 Chlorophyceae, 10 Cyanophyceae, and 8 other species. Bacillariophyceae and Chlorophyceae were dominated during the seasonal succession of phytoplankton community, especially summer season. Bacillariophyceae was dominated from spring season to summer season and Chlorophyceae was dominated at summer season and autumn season. However, the dominance of Cyanophyceae generally developed at summer season in eutrophic water was not observed. From the analysis of correlation coefficient between environmental factors and phytoplankton cell number, we confirmed that there was a negative correlation between turbidity and cyanobacteria cell number (P<0.01). This result indicated that turbid water acts as the inhibitor of the cyanobacteria growth than other phytoplankton community.

• 생태와환경
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• 제35권1호통권97호
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• pp.1-9
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• 2002

팔당호 지류인 경안천의 입자태 및 무기 영양염의 동태와 이들이 식물플랑크톤의 군집구조의 천이에 미치는 영향을 규명하기 위하여 1993년 8월 18일부터 11월 13일까지 주 1회의 조사를 14주 동안에 걸쳐서 수행하였다. 질산성 질산염은 조사기간 중 항상 풍부하였고 인산염과 규산염은 갈수기에 급격히 감소하는 경향을 보였다. Chlorophyll a의 값은 1993년 8월 21일 $90.6\;{\mu}g/l$로 최대 값이 관찰되었으며 10월 중순 이후부터는 $15{\sim}16\;{\mu}g/l$을 유지하였다. 입자태 유기탄소와 입자태　유기질소는 매우 풍부한데 비해, 입자태 유기인의 농도는 최저$0.3\;{\mu}g\; atm/l$의 낮은 능도 분포를 보였으며, 입자태 유기탄소 및 유기질소의 변화양상은 chlorophyll a의 변차양상과 잘 일치하였으며, 이것은 입자태 유기탄소 및 질소는 식물플랑크톤의 성장에 의한 내생적 공급에 의함을 의미한다. 이와는 반대로 경안천의 인의 공급은 외부로부터 공급되고 있으며, 항상 인산염이 식물플랑크톤의 제한인자로 작용하지만, 때때로 낮은 Si/P ratio을 나타내어 규산염의 고갈 현상이 관찰되었다. 이 결과는 때로는 식물플랑크톤의 성장에 인산염 보다는 규산염이 제한 인자로 작용한다는 것을 암시한다. 인산염이 제한 인자로 작용하는 시기에는 규조류가 우점하고 있었으며, 규산염이 제한인자로 작용하는 시기 (9월 $11{\sim}18$일, 10월 $2{\sim}16$일)에는　남조류와 녹조류가 우점 하였다. 특히,　남조류 중에서 Anabaena, Microcystis및 Oscillatoria가 우점종으로 출현하였다.

• Ocean Science Journal
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• 제41권1호
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• pp.31-41
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• 2006

Seasonal changes of abundance of the main phytoplankton groups of species (diatoms, dinoflagellates, chrysophytes, small flagellates and cryptophytes) and a set of environmental parameters were investigated in coastal and pre-estuarine waters of Peter the Great Bay (East/Japan Sea) in May-October of 1998 and 1999. Three periods of mass development were revealed: spring, summer and autumn blooms, with successive change of species. The conditions favourable for each group of species were determined. Driving mechanisms of the succession include nutrients transport through seasonal pycnocline by turbulent mixing, terrestrial nutrients supply by monsoon floods, nutrients supply by upwellings, and light control by the thickness of upper mixed layer. Summer succession could be explained by a simple SST-MLD diagram similar to Pingree S-kh diagram with sea surface temperature as indicator of stratification (S) and mixed layer depth as indicator of light availability (kh).

• Ocean and Polar Research
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• 제32권2호
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• pp.97-111
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• 2010

Phytoplankton production is affected by various physico-chemical factors of environment. However, one of the most critical factors generally accepted as controlling primary production of phytoplankton is nutrients. It has recently been found that the succession of phytoplankton groups and species are closely related to the chemical properties of ambient water including nutrient limitation and their ratios. In Jangmok Bay, silicate and nitrate are primarily supplied by rainfall, while phosphate and ammonia are supplied by wind stress. Typhoons are associated with rainfall and strong wind stress, and when typhoons pass through the South Sea, such events may induce phytoplankton blooms. When nutrients were supplied by heavy rainfalls during the rainy season and by summer typhoons in Jangmok Bay, the dominant taxa among the phytoplankton groups were found to change successively with time. The dominant taxon was changed from diatoms to flagellates immediately after the episodic seasonal events, but returned to diatoms within 3~10 days. Pseudo-nitzschia spp. were dominant mainly in the presence of low phosphate levels during the first of the survey which included the rainy season, while Skeletonema costatum was dominant when phosphate concentrations were high due to the strong wind stress during the latter half of the survey as a result of the typhoon. The competition between S. costatum and Chaetoceros spp. appeared to be regulated by the silicate concentration. S. costatum preferred high silicate and phosphate concentrations; however, Chaetoceros spp. were able to endure low silicate concentrations. These results implied that, in coastal ecosystems, the input patterns of each nutrient supplied by rainfall and/or wind stress appeared to contribute to the summer succession of phytoplankton groups and species.

• ALGAE
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• 제20권3호
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• pp.197-205
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• 2005

Temporal variability in lake phytoplankton is controlled by a complex between hydrological and chemical factors, and biological interactions. We explored annual change of phytoplankton in Lake Daecheong, using phytoplankton analysis data from 1997 to 2002 (except 2000). The standing crop of phytoplankton was ranged from 3.5 x 10 to 1.5 x 106 cells mL$^{-1}$ and the highest mean value was at site 1. The class composition ratios of phytoplankton standing crop were divided into three classes. From January to March, diatoms showed a dominance (68.1-77.7%). From April to June, diatoms were mixed with cryptomonad etc. or blue-green algae. From July to October, blue-green algae showed a dominance (54.7-84.0%). In the case of green algae, the class composition ratios were below 10%. But green algae appeared all the year round.

• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2004년도 학술대회
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• pp.53-53
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• 2004

• 생태와환경
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• 제50권4호
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• pp.441-451
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• 2017

2016년 8월 19일부터 12월 31일까지 현장원수와 퇴적물이 주입된 현장 배양장치 실험을 통해 환경요인의 영향에 따른 식물플랑크톤 기능그룹(phytoplankton functional group, PFG)의 천이 특성을 연구하였다. 본 연구에서 확인된 식물플랑크톤은 총 27속 50종이었으며, 분류군별로는 녹조류 30종, 규조류 11종, 남조류 7종, 편모조류 2종으로 나타났다. 실험구에서 총 25속 47종(녹조류 30종, 규조류 9종, 남조류 6종, 편모조류 2종), 대조구에서 총 23속 45종(녹조류 26종, 규조류 10종, 남조류 7종, 편모조류 2종)의 식물플랑크톤이 각각 확인되었다. 식물플랑크톤 기능그룹(PFG)은 총 19개(B, C, D, F, G, H1, J, K, Lo, M, MP, N, P, S1, $T_B$, $W_0$, X1, X2, Y)로 확인되었으며, 실험구와 대조구에서는 H1을 제외하고 18개의 PFG가 모두 출현하였다. 생체 부피(biovolume)에 기초했을 때 $W_0$, J 및 M 그룹은 원수만 주입된 대조구와 비교하여 원수와 퇴적물이 주입된 실험구에서 영양염의 내부순환(internal cycling)의 영향으로 더 높은 생체부피를 보이면서 뚜렷한 천이 양상을 나타내었다. PCA 분석 결과에 기초할 때 PFG의 천이 양상은 영양염, 수온 및 조도 등의 주요 환경인자들과의 상관성에 따라 뚜렷한 차이를 나타내었다. 결론적으로 본 연구에서 PFG를 적용하여 주어진 환경조건에서 식물플랑크톤 적응 및 천이(성장) 특성을 확인할 수 있었으며, PFG는 향후 국내 수계의 식물플랑크톤 천이를 이해하기 위한 새로운 방법이 될 수 있을 것으로 생각된다.

• 생태와환경
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• 제50권1호
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• pp.57-69
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• 2017

본 연구는 2016년 2월 23일부터 6월 28일까지 현장규모대형 배양장치(Pilot Culture System)에서 환경요인의 영향에 따른 저층 침전현상 및 겨울철 월동 이후 조류 군집 천이 특성에 대해 연구하였다. 겨울(2월)에 실험군에서 남조류, 녹조류 및 규조류 총 17종의 월동(overwintering)이 관찰되었으며, 월동한 식물플랑크톤은 재부유 이후 뚜렷한 천이양상을 보였다. 식물플랑크톤 천이 과정에는 총 28속 56종 출현하였다. 실험군에서는 총 24속 52종이 출현하였으며 분류군별로는 녹조류가 35종(67.3%)으로 가장 높았고 규조류 9종(17.3%), 남조류 5종(9.6%), 기타조류 3종(5.8%) 순으로 나타났다. 대조군에서는 총 14속 25종이 출현하였고 녹조류가 17종(68.0%)으로 가장 높은 비율을 차지하였으며, 그 외 남조류와 기타조류는 각 3종(12.0%), 규조류 2종(8.0%)으로 나타났다. 식물플랑크톤 현존량은 실험군에서 $40{\sim}325,450cells\;mL^{-1}$, 대조군에서 $900{\sim}37,100cells\;mL^{-1}$로 실험군보다 대조군에서 매우 낮은 현존량 차이를 보였다. 우점종은 실험군에서는 Monoraphidium minutum, Microcystis aeruginosa, Rhodomonas lacustris, Ankyra judai, Chlorella vulgaris가, 대조군에서는 M. minutum, Coenochloris cf. pyrenoidosa가 천이과정에서 주요 우점종으로 확인되었다. 실험군에서의 식물플랑크톤 천이양상은 뚜렷하게 확인되었으며, 이화학적(수온, 영양염) 및 생물학적 요인 간의 명확한 영향을 받는 것으로 확인되었다. 반면 대조군에서는 이화학적 요인인 영양염의 영향을 크게 받는 것으로 확인되었다. 결론적으로 이번 연구는 외부유입 요인들이 배제된 상태에서 수체 내 주요 분류군의 월동 및 천이가 내부 환경요인의 상호작용만으로 발생할 수 있음을 잘 보여주었으며 향후 식물플랑크톤 천이양상을 이해하는 기초자료로 활용될 것으로 기대된다.