• Journal of the korean society of oceanography
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• 제35권1호
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• pp.46-55
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• 2000

In order to understand the role of heterotrophic protists in the coastal waters off Inchon, abiotic and biotic factors were measured from January 1992 to February 1993. Microbial carbon biomass (mean212.9$^{\pm}$119.1 $^{\mu}$gC/1) was composed of 4.2% bacteria, 0.3% cyanobacteria, 12.l% autotrophic nanoflagellates, 6.6% heterotrophic nanoflagellates, 5.8 heterotrophic ciliates and 71.0% diatom and Mesodinium spp. The carbon biomass of heterotrophic protists (heterotrophic nanoflagellates and ciliates) was highest in October 1992 (mean 37.8$^{\pm}$22.5 $^{\mu}$gC/1), and was low in August 1992 (mean 21.2$^{\pm}$10.8 $^{\mu}$gC/1) and in February 1993 (mean 19.5$^{\pm}$6.4 $^{\mu}$gC/1). However, the contribution of heterotrophic protists to total microbial carbon biomass was higher in January 1992 and February 1993 (about 21%) when the phytoplankton was dominated by nanoplankton than in August and October (about 9%) when large diatoms occurred in large numbers. This study suggests that in Kyeonggi Bay heterotrophic protists might play a more important role as prey for zooplankton and as consumers of bacteria & small phytoplankton in less productive seasons (especially winter) than in productive seasons (autumn), and that the classic trophic pathway from diatoms through copepods to fish might be dominant nearly every season.

• 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.

• 수산해양교육연구
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• 제28권5호
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• pp.1417-1434
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• 2016

Starting from the February 2008 till the end of November 2014, abundance of phytoplankton and their composition living in the coastal waters of Kyoungju city were investigated. Environmental and biological properties were also observed at 10 different stations on a seasonal basis. Due to the environmental variables, fluctuating pattern was appeared during the entire period of observation with different degree, as compared to those found in other costal waters in the East Sea. The concentration of phosphate was turned out to be very low which was even less than threshold level in the study area. Phytoplankton community structure was dominated by diatoms (both micro- and nanoplankton fractions) for several years and seasonal succession was also relied on the diatoms. The importance of dinoflagellates in the community was relatively low. Abundance of phytoplankton was heavily affected by physical factors in the surface water, however, affected more by chemical factors including nutrients in the deep water. For periods of this study, the phosphate concentrations was observed in an extremely low, which indicates that the main limiting factor affecting phytoplankton growth could be phosphate.

• 환경생물
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• 제22권3호
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• pp.426-437
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• 2004

To understand the phytoplankton community in adjacent waters of Ulchin nuclear power plant (UNPP), abundance and the size fractionated $chl-\alpha$ concentrations were evaluated through seasonal interval sampling from April 2003 to February 2004. A total of 211 different phytoplankton species was observed and mean abundance of phytoplankton in each study period ranged from 244,286 to 1,221,779 cells $L^{-1}$. The contributions of microplankton $(>20\mu{m})$ to total phytoplankton abundance ranged from 42.5 to 83.6% (average 66.1%) and those of nanoplankton $(>20\mu{m})$ ranged from 16.4 to 57.5% (average 33.9%). Total chl-$\alpha$ concentrations of phytoplankton ranged from 0.52 to $2.26\mu{g}\;L^{-1}$. The contribution of chl-$\alpha$ concentrations of microplankton was higher than that of nano- and picoplankton through the study period with exception of July 2008. The results of abundances and $chl-\alpha$ concentrations suggest that microplankton has an important role in adjacent waters of UNPP. The diminution of abundances and $chl-\alpha$ concentrations of phytoplankton was observed after passage through the cooling water system, but it was gradually recovered by mixing with the ambient waters. Our results suggested that the influence of thermal discharges on phytoplankton should be restricted within narrow limits around outlet area of thermal effluents.

• Ocean and Polar Research
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• 제28권2호
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• pp.107-117
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• 2006

Freshwater algal studies in North polar environments are relatively few. This study presented the algal-flora, -biomass and genetic features of dominant cells collected from temporary ponds around the Polar Research Station (PRS), Norway. Water samples were collected from 4 stations around PRS, and analyzed for their environmental and biological variables. Water temperature, salinity and conductivity ranged from 5 to $10^{\circ}C$, 0.1 to $0.3%_{\circ}$ and 0.21 to $0.36{\mu}S/cm$, respectively. Chlorophyll a concentration ranged from 1.8 to $11.1{\mu}g/l$, and that of the size-fractionated cells was recorded from 0.7 to $1.1{\mu}g/l$ in picoplankton 0.3 to $6.5{\mu}g/l$ in nanoplankton, and 0.4 to $3.9{\mu}g/l$ in microplankton respectively. Algal flora in the present study was recorded as 10 genera, in which Chlamydomonas, particularly, was dominant in all studied sites. By comparison of Chlamydomonas 18S rDNA sequences, including two isolates from PRS, they formed a distinct clade against others: sequence similarity was significantly low (<97.2%) with C. noctigama, being the highest score by BLAST search in GenBank. This study was valuable for basic knowledge regarding the freshwater algae around PRS and their genetic information.

• Ocean and Polar Research
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• 제30권3호
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• pp.261-275
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• 2008

The profile of a fixed site at station M ($34.77^{\circ}N,\;129.13^{\circ}E$) in the Korea Strait was studied from March 2006 to February 2007. The aim was to understand the relationship between the annual thermal stratification pattern and seasonal variation in phytoplankton community structure. Physicochemical factors including temperature, salinity and nutrient concentrations, which strongly influence the proliferation and diversity of phytoplankton, were measured. The study period was divided into three due to the characteristic of thermohaline structures; mixed I (March-May 2006), stratified (June-November 2006) and mixed II(December 2006-Feburuary 2007). Diatoms dominated during the mixed I (89%) and II (48%) periods, while nanoplankton group occupied over 83% of total population during the stratified period. The dominant species during the mixed I and II was Chaetoceros socialis (47% and 29%, respectively), while during the stratified period Gyrodinium sp.(4%) was the most dominant. Averaged total chl a concentrations during the mixed I and II periods were 0.61 mg $m^{-3}$ and 0.72 mg $m^{-3}$, respectively, which were at least two-fold higher than that during the stratified period (0.30 mg $m^{-3}$). The vertical mixing and convection process of the water column induced nutrient supply from the bottom layer to the euphotic zone. It also led to the dominance of diatoms during the mixed periods, whereas small phytoplankton prevailed over large phytoplankton as stratification blocked the upward movement of nutrients to subsurface during the stratified period. During the mixed I and II periods, microplanktonic chl a dominated concentrations (50% and 48%, respectively), while picoplanktonic chl a occupied over 37% of total chl a during the stratified period.

• 한국해양학회지
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• 제19권2호
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• pp.172-186
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• 1984

光陽灣 植物 플랑크톤의 分布와 環境과의 관계에 대한 硏究가 1982년 3월 에서 12월까지 4회에 걸쳐 계절별로 이루어졌다. 本 硏究에서 總 211種이 同定 되었는데 이들은 67屬 196種 14變種 1品種으로 構成되었다. 季節別 우점종은 春季 Rhiwosolenia deiicatula, Chroomonas sp, 夏季 Chroomonas sp. 秋季 Chaetoceros debilis, C. socialis, 冬季 Skeletonema costatum, Chroomonas sp.로 季節에 따른 우점종의 遷移현상이 뚜렷하였다. 식물 플랑크톤 現在量의 時間的 變化는 암모니아態 질소의 농도, 동물 플랑크톤에 의한 攝食壓力, 水溫의 變化와 밀접한 관계가 있으며 特히 春季 硅藻類의 大發生은 암모니아態 질소의 농도와 높은 相關性을 보였다. 種 多樣性指數는 비교적 낮다. 전 群集內에서 nanoplankron 의 年 평균 비율은 36.5%로 光陽灣 일차생산과 먹이망에서 중요한 位置를 占 하였다. 植物 플랑크톤의 空間分析에 의하여 硏究水域은 대체로 淡水 流入이 많은 蟾津강 河口域, 外洋水의 영향이 적은 灣 右側域, 外洋水의 영향이 큰 灣 右側域 등 3個의 특징적인 水域으로 區分된다. 공장 폐수도 植物 플랑크톤 分布에 영향을 미치는 것으로 나타났다.

• 생태와환경
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• 제37권2호통권107호
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• pp.149-179
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• 2004

국내산 담수 섬모충 플랑크톤의 분류 및 생태학적 특성을 파악하기 위해 2000년 12월 15일부터 2001년 12월6일까지 팔당호에서 표층수를 채집하였다. 조사결과 총 6목 7과 10속 12종의 우점종이 분류, 동정 되었으며 이들은 모두 국내 미기록 종으로서 생태학적 특성과 함께 기재하였다. 우점적으로 동정된 섬모충 플랑크톤의 대부분은 부영양수역에서 보고된 종들이었으며, 저수온기인 동계와 춘계에는 nanoplankton을 먹이로 하는 비교적 대형종인 Codonella cratera, Rimostrombidium lacustris, Strobilidium caudatum, Limnostrombidium viride, Pelagostrombidium fallax, Stylonychia sp., Pseudostrombidium planktonticum, Phascolodon vorticella등이 출현하는 반면, 고수온기인 하계와 추계에는 박테리아를 먹이로 하는 Rimostrombidium hyalinum, Rimostrombidium brachykinetum, Halteria gradinella, Vorticella convallaria와 같은 소형종들이 우점하였다.

• 한국해양학회지:바다
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• 제7권3호
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• pp.108-128
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• 2002

고리, 월성, 울진 그리고 영광해역에서 1992년부터 1996년까지 식물플랑크톤의 생태학적 특성을 이해하고자, 식물플랑크톤의 현존량 및 엽록소 농도가 조사되었고, 무생물학적 환경요인들과의 상관관계를 분석하였다. 고리, 월성, 울진 및 영광해역에서 연구기간동안 총 질소의 평균 농도는 각각 0.101, 0.094, 0.072및 0.108mg/$\ell$이었고 ,인산염은 각각 0.007, 0.008, 0.006 및 0.009mg/$\ell$이었다 N:P ratios는 고리, 월성, 울진 및 영광해역에서 3.2~57.3, 3.1~109.0. 2.6~102.0 및 1.0~165.0으로 극심한 변동을 나타내었다. 또한 부유물질 농도는 각각 평균 18.7, 16.7, 11.6 및 52.7mg/$\ell$이었고, 투명도는 각각 평균 3.8, 5.4, 7.9및 0.7m이었다. 총 현존량은 고리, 월성, 울진 및 영광해역에서 각각 평균 710,659, 687,508, 656,245 그리고 1,278,173ce11s/$\ell$로 영광해역에서 가장 높았으며, 나머지 해역은 서로 유사하였다. 연구해역 모두 전반적으로 높은 현존량을 나타내었으며, 이 중 소형플랑크톤의 현존량은 고리, 월성, 울진 및 영광해역에서 각각 평균 357,546, 333,638, 276,407그리고 592,975ce11s/$\ell$이었으며, 미소플랑크톤의 현존량은 고리, 월성, 울진 및 영광해역에서 각각 평균 353,113, 353,870, 379,838그리고 714,846cells/$\ell$로 영광 해역에서 가장 높게 나타났다. 규조류는 고리, 월성, 울진 및 영광해역에서 각각 평균 282,009, 284,710, 238,758 그리고 574,563cells/$\ell$로 영광해역에서 가장 높았으며, 고리, 월성 및 울진 해역은 봄철에 높고 가을철에 낮은 계절분포를 보인 반면에 영광해역은 여름철에 낮은 현존량을 기록하였다. 와편모조류는 각각 평균 46,078, 35,401, 32,906 그리고 16,749cells/$\ell$로 서해 영광해역이 가장 낮게 나타났고, 고리와 영광해역은 여름철 그리고 울진해역은 가을철에 높은 계절분포를 나타내었다. 엽록소 $\alpha$농도는 연구해역에서 평균 2.16~4.28$\mu\textrm{g}$/$\ell$로 영광해역에서 가장 높게 나타났다. 종 다양성 지수는 연구해역에서 2.11~2.24 이었으며, 동해연안은 겨울철에 불안정하고 여름철에 안정된 군집구조를 이루는 반면에, 서해의 영광해역은 겨울철과 여름철에 안정된 군집구조를 이루고 있었다. 식물플랑크톤 현존량과 무생물학적 환경요인들과의 상관관계 분석결과, 연구해역과 계절에 따라 그 영향의 정도에서 차이를 보이지만, 투명도, 부유물질 및 영양염(N $O_3$$^{-}$-N, P $O_4$$^{3-}$ -P)등이 식물플랑크톤 현존량 분포에 영향을 주는 것으로 나타났다.

• 한국산학기술학회논문지
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• 제16권11호
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• pp.7761-7772
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• 2015

제주 바다목장 해역의 식물플랑크톤 군집의 시 공간적 분포특성을 파악하기 위해 8개 정점의 표층과 10m 수심에서 2008년 4월부터 11월까지 4회 현장조사를 실시하였다. 식물플랑크톤 출현종은 63속 106종으로 다양하였다. 분류군별은 규조류가 61.3%, 와편모조류가 34.9%를 차지하였고, 시간적으로는 가을에 다양한 종이 출현하였다. 식물플랑크톤 현존량은 여름 $0.6cells{\cdot}mL^{-1}$에서 봄 $64.0cells{\cdot}mL^{-1}$의 범위로 매우 낮았다. 평균 세포밀도에 의한 연변동은 연평균 최저 11월 $0.9cells{\cdot}mL^{-1}$에서 최고 4월 $37.0cells{\cdot}mL^{-1}$로 변화하여 연평균 $11.7cells{\cdot}mL^{-1}$의 낮은 세포밀도를 나타내었다. 우점종은 4월에 Skeletonema costatum-like species(ls)에 의해 극우점되었다. 6월은 Torodinium teredo, Cylindrotheca closterium, Scrippsiella trochoidea, 9월은 S. costatum-ls, Thalassionema nitzschioides, Pseudo-nitzschia pungens, Ebria tripartita 그리고 11월은 Corethron pennatum, Dictyocha fibura, Neoceratium teres가 우점 출현하여, 기존 결과와는 다른 결과를 나타내었다. 생태지수 중에 종 다양성 지수는 4월과 9월에 낮고 6월과 11월에 높았다. 식물플랑크톤 군집으로 본 제주 바다목장 해역의 생물해양학적 특성은 연간 크기가 작은 나노플랑크톤에 의한 점유률이 높았고, 특정 종에 의해 극우점되는 외부 영양염류 유입보다는 생태내의 물질순환에 따른 재생산비율이 높은 것으로 판단되었다.