Influence of the tidal front on the three-dimensional distribution of spring phytoplankton community in the eastern Yellow Sea

Choi, Byoung-Ju,Lee, Jung A,Choi, Jae-Sung,Park, Jong-Gyu,Lee, Sang-Ho,Yih, Wonho Pergamon Press 2017 Chemosphere Vol.173 No.-

<P><B>Abstract</B></P> <P>Hydrographic observation and biological samplings were conducted to assess the distribution of phytoplankton community over the sloping shelf of the eastern Yellow Sea in May 2012. The concentration of chlorophyll <I>a</I> was determined and phytoplankton was microscopically examined to conduct quantitative and cluster analyses. A cluster analysis of the phytoplankton species and abundance along four observation lines revealed the three-dimensional structure of the phytoplankton community distribution: the coastal group in the mixed region, the offshore upper layer group preferring stable water column, and the offshore lower layer group. The subsurface maximum of phytoplankton abundance and chlorophyll <I>a</I> concentration appeared as far as 64 km away from the tidal front through the middle layer intrusion. The phytoplankton abundance was high in the shore side of tidal front during the spring tide. The phytoplankton abundance was relatively high at 10-m depth in the mixed region while the concentration of chlorophyll <I>a</I> was high below the depth. The disparity between the profiles of the phytoplankton abundance and the chlorophyll <I>a</I> concentration in the mixed region was related to the depth-dependent species change accompanied by size-fraction of the phytoplankton community.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Physical environment, chlorophyll concentration and phytoplankton community were investigated in the eastern Yellow Sea. </LI> <LI> Three-dimensional structure of phytoplankton communities was identified in the tidal front region. </LI> <LI> Phytoplankton abundance and chlorophyll <I>a</I> concentration were high in the shore side of the front during the spring tide. </LI> <LI> Subsurface maximum of phytoplankton abundance appeared about 64 km away from the front through the middle layer intrusion. </LI> <LI> Profiles of phytoplankton abundance and chlorophyll <I>a</I> concentration were different due to depth-dependent species change. </LI> </UL> </P>

진해만에서 물리화학적 환경요인이 식물플랑크톤 색소 및 군집조성의 시공간적 변화에 미치는 영향

나수진,이지영,김정배,구준호,이가람,황현진 해양환경안전학회 2021 해양환경안전학회지 Vol.27 No.2

The aim of this study was to investigate the spatial and temporal distribution of phytoplankton biomass and community composition in Jinhae Bay on the southern coast of Korea. Phytoplankton pigment analysis was conducted using ultra performance liquid chromatography (UPLC) were conducted from April to December 2019 at seven stations. Temperature, salinity, and dissolved oxygen (DO) and inorganic nutrients (dissolved nitrogen, dissolved phosphorus, and orthosilicic acid) were measured to investigate the environmental factors associated with the structure of phytoplankton community. Phytoplankton biomass (Chl-a) was the highest in July (mean 15.4±4.3 µg/L) and the lowest in December (mean 3.5±0.6 µg/L). Fucoxanthin was the most abundant carotenoid and showed a similar variation pattern to Chl-a, peridinin, and Chl-b. Phytoplankton community composition analysis showed that diatoms were a predominant group with an average abundance of 70% whereas chlorophytes, cryptophytes, and dinoflagellates often appeared with lower averages. Further, the dominance of diatoms was closely correlated with water temperature and N:P ratio, which might be influenced by high temperatures in the summer and nutrient loading from the land. Additionally, freshwater and nutrient input by rainfall was estimated to be the most important environmental factor. Hence, the spatial and temporal variations in the composition of phytoplankton pigments and phytoplankton community were correlated with physicochemical and environmental parameters. 본 연구에서는 ultra performance liquid chromatography(UPLC)를 이용하여 진해만의 식물플랑크톤 생체량 및 군집구조의 시공간적 분포에 미치는 환경요인의 영향을 조사하였다. 이를 위해 2019년 4월에서 12월까지 총 5회에 걸쳐 7개 정점에 대한 식물플랑크톤 색소분석과 수온, 염분, 용존산소(DO), 영양염(DIN, DIP, Si(OH)4) 등의 환경요인 분석을 행하였다. 조사기간 중 식물플랑크톤의 생체량(Chl-a)은 7월(평균 15.4±4.3 µg/L)에 가장 높았고, 12월(평균 3.5±0.6 µg/L)에 가장 낮았다. 보조색소의 경우 fucoxanthin이 가장 많이 검출되었고 그 다음으로 peridinin, Chl-b 순으로 나타났으며, 이들의 월 변동은 Chl-a와 유사한 경향을 보였다. 식물플랑크톤 군집분석결과, 규조류가 평균 70%로 가장 우점하였으나, 일부 녹조류, 은편모조류, 와편모조류가 출현하기도 하였다. 우점종인 규조류는 특히 수온 및 N:P ratio와 밀접하게 연관되어 있어서 여름철 고온환경 및 육상으로부터의 영양염 유입에 민감하게 반응하는 것으로 추론되었다. 또한 식물플랑크톤 색소 및 종조성은 전반적으로 계절에 따른 물리화학적 환경요인의 변화 및 지형적 특성과 연관되어 있으며 강우로 인한 담수 및 영양염 공급에 큰 영향을 받는 것으로 추정되었다.

2020년 하계 장강 저염수가 이어도 해양과학기지 주변 해역의 식물플랑크톤 다양성 및 개체수 변화에 미치는 영향

김지훈,최동한,이하은,정진용,정종민,노재훈 해양환경안전학회 2021 해양환경안전학회지 Vol.27 No.7

여름철 장강 저염수의 확장은 북부 동중국해의 환경 및 식물플랑크톤 다양성과 군집구조에 영향을 미치는 주요 요인으로 알려져 있다. 2020년 하계는 장강 저염수의 방류량이 매우 높았던 시기로 환경 특성 변화에 따라 식물플랑크톤 다양성 및 군집구조에 미치는 동력을 이해하기 위해 현장관측을 수행하였다. 2020년 8월 16일~17일 이어도호 승선조사와 2020년 8월 15일~21일 이어도 해양과학기지(IORS)에서 체 류조사를 실시하였다. 조사 정점들에서 CTD로 측정한 결과 조사 수역 남서쪽은 장강 저염수의 영향을 받아 염분이 낮고 엽록소 형광값이 높 았으며, 대마난류의 영향을 받은 남동수역은 염분이 높고 엽록소 형광값이 낮았다. 12개 정점의 표층수 시료의 엽록소 a 농도는 미소형(20~3 μm) 및 소형(> 20 μm) 식물플랑크톤의 생체량이 우점함을 나타냈으며, 대마난류수의 영향을 받은 정점에서만 초미소 식물플랑크톤(< 3 μm) 생체량이 약 50%를 차지하였다. 이러한 표층수의 식물플랑크톤 크기 분포는 영양염류 공급과 관련되어 장강 저염수의 높은 질산염 공급을 받는 정점들은 소형 식물플랑크톤의 생체량 기여율이 높았다. 형태분류 결과 미소형 및 소형 식물플랑크톤은 총 45종이며, 이들 중 우점 분 류군은 규조류인 Guinardia flaccida, Nitzschia spp.와 와편모조류인 Gonyaulax monacantha, Noctiluca scintillans, Gymnodinium spirale, Heterocapsa spp., Prorocentrum micans, Tripos furca 등이었다. 대마난류의 영향을 받으며 질산염 농도가 낮은 정점들은 광합성 초미소 진핵생물(PPE)의 개 체수와 광합성 초미소 원핵생물(PPP)인 Synechococcus의 개체수가 높았다. 질산염/인산염 비는 대부분 정점에서 인산염 제한을 받고 있음을 나타냈다. 유세포 분석 결과 Synechococcus 개체수는 난류의 영향을 받는 빈영양 수역의 정점들에서 높은 개체수를 보였다. NGS 분석 결과 PPP 중 Synechococcus는 29개의 clades가 나타났고, 이 중 한 시료에서 한 번이라도 1% 이상의 우점율을 보인 clade는 11개로 나타났다. 표층수 에선 clade II가 우점분류군이었으며 SCM 층에서 다양한 clades(I과 IV 등)가 차우점군들로 분포하였다. Prochlorococcus 속은 난류 수역에서 high light adapted 생태형이 출현하는 양상을 보였으며 북쪽 수역에선 출현하지 않았다. PPE는 총 163개의 높은 operational taxonomic units (OTUs) 다양성을 보였으며, 이 중 한 시료에서 한 번이라도 5% 이상의 우점률을 나타낸 OTU는 총 11개였다. 장강 저염수의 영향을 받는 정 점의 표층수에선 Amphidinium testudo가 우점 분류군이었으며, SCM 층에서 녹조류가 최우점하였다. 대마난류의 영향을 받는 해역에서는 다양 한 분류군의 착편모조류가 우점하였다. IORS에서의 관측 결과도 주변 정점들과 식물플랑크톤 생체량, 크기분포, 다양성에서 유사한 수준을 나타냈다. 이번 연구 결과는 장강 저염수의 영향에 따른 식물플랑크톤의 반응을 다양한 분야에서 확인할 수 있었다. 또한, IORS와 승선조사 를 비교하여 IORS 관측이 장강 저염수의 식물플랑크톤 동적 역학 모니터링에 활용할 수 있음을 확인하였다. 향후 기후변화에 따라 나타날 동중국해 하계 환경 및 생태계의 변화에 대비하여 IORS의 효과적 이용 방안 수립이 필요할 것으로 판단된다. The expansion of the Changjiang Diluted Water (CDW) plume during summer is known to be a major factor influencing phytoplankton diversity, community structure, and the regional marine environment of the northern East China Sea (ECS). The discharge of the CDW plume was very high in the summer of 2020, and cruise surveys and stationary monitoring were conducted to understand the dynamics of changes in environmental characteristics and the impact on phytoplankton diversity and community structure. A cruise survey was conducted from August 16 to 17, 2020, using R/V Eardo, and a stay survey at the Ieodo Ocean Research Station (IORS) from August 15 to 21, 2020, to analyze phytoplankton diversity and community structure. The southwestern part of the survey area exhibited low salinity and high chlorophyll a fluorescence under the influence of the CDW plume, whereas the southeastern part of the survey area presented high salinity and low chlorophyll a fluorescence under the influence of the Tsushima Warm Current (TWC). The total chlorophyll a concentrations of surface water samples from 12 sampling stations indicated that nano-phytoplankton (20–3 μm) and micro-phytoplankton (> 20 μm) were the dominant groups during the survey period. Only stations strongly influenced by the TWC presented approximately 50% of the biomass contributed by pico-phytoplankton (< 3 μm). The size distribution of phytoplankton in the surface water samples is related to nutrient supplies, and areas where high nutrient (nitrate) supplies were provided by the CDW plume displayed higher biomass contribution by micro-phytoplankton groups. A total of 45 genera of nano- and micro-phytoplankton groups were classified using morphological analysis. Among them, the dominant taxa were the diatoms Guinardia flaccida and Nitzschia spp. and the dinoflagellates Gonyaulax monacantha, Noctiluca scintillans, Gymnodinium spirale, Heterocapsa spp., Prorocentrum micans, and Tripos furca. The sampling stations affected by the TWC and low in nitrate concentrations presented high concentrations of photosynthetic pico-eukaryotes (PPE) and photosynthetic pico-prokaryotes (PPP). Most sampling stations had phosphate-limited conditions. Higher Synechococcus concentrations were enumerated for the sampling stations influenced by low-nutrient water of the TWC using flow cytometry. The NGS analysis revealed 29 clades of Synechococcus among PPP, and 11 clades displayed a dominance rate of 1% or more at least once in one sample. Clade II was the dominant group in the surface water, whereas various clades (Clades I, IV, etc.) were found to be the next dominant groups in the SCM layers. The Prochlorococcus group, belonging to the PPP, observed in the warm water region, presented a high-light-adapted ecotype and did not appear in the northern part of the survey region. PPE analysis resulted in 163 operational taxonomic units (OTUs), indicating very high diversity. Among them, 11 major taxa showed dominant OTUs with more than 5% in at least one sample, while Amphidinium testudo was the dominant taxon in the surface water in the low-salinity region affected by the CDW plume, and the chlorophyta was dominant in the SCM layer. In the warm water region affected by the TWC, various groups of haptophytes were dominant. Observations from the IORS also presented similar results to the cruise survey results for biomass, size distribution, and diversity of phytoplankton. The results revealed the various dynamic responses of phytoplankton influenced by the CDW plume. By comparing the results from the IORS and research cruise studies, the study confirmed that the IORS is an important observational station to monitor the dynamic impact of the CDW plume. In future research, it is necessary to establish an effective use of IORS in preparation for changes in the ECS summer environment and ecosystem due to climate change.

청계만 식물플랑크톤의 종조성과 개체수의 계절적 변동

정병관 ( Byung Kwan Jeong ),지성 ( Sung Ji ),신용식 ( Yong Sik Shin ) 한국환경과학회 2012 한국환경과학회지 Vol.21 No.3

Three embankments, namely Changpo, Bokkil and Guil, in Chunggye Bay were investigated to assess the influence of environmental changes to phytoplankton size structure, distribution of species and standing crops. Three stations was sampled near at each embankment in Nov. 2006, Feb. 2007, May 2007 and Aug. Phytoplankton were classified into net-size (>20㎛) and nano-size (<20㎛). In summer, the freshwater discharge seemed to have influence in the decrease of salinity and in the increase of turbidity, ammonium and phosphorus concentrations. Chl a concentration and phytoplankton abundance in Feb. 2007 were observed to be generally higher in all stations compared to other periods. Net-size phytoplankton was observed to be higher in Feb. 2007 and May 2007 compared to nano-sized phytoplankton. However, there was shift in phytoplankton composition in Nov. 2006 and Aug. 2007. Phytoplankton under seven class (Bacillariophyceae, Chlorophyceae, Chrysophyceae, Cryptophyceae, Cyanophyceae, Dinophyceae, Euglenophyceae) was identified during the study period. It was found out that the major phytoplankton class was Bacillariophyceae. Phytoplankton was more diverse in autumn compared to any other season. Cyanophyceae was increased in summer. In rainy season, change in physical factors (salinity, transparency) seemed to have more influence on phytoplankton growth compared to inorganic nutrients.

팔당호의 식물플랑크톤 군집 연구

김영길(Young Geel Kim),신윤근(Youn Keun Shin),최준길(Jun Kil Choi) 상지대학교 환경과학기술연구소 2000 환경과학연구 Vol.6 No.1

  팔당호에서 하계 식물플랑크톤의 군집구조를 파악하기 위하여 99년 7월과 9월에 팔당호로 유입되는 북한강, 남한강, 경안천 유입부와 팔당호 수계에서 6개 지점을 선정하여 총 2회 조사하였다. 그리고 환경요인과의 관계를 알아보기 위하여 팔당호에서 수온, 투명도, 용존산소, 고형부유물질, 규산염, 총인, 엽록소-a를 조사하였다. 팔당호에서 출현한 식물플랑크톤은 총 162종으로서 78속 108종 4품종 25변종 25미동정종으로 구성되었다. 녹조류가 90종으로 전체에서 55.5%의 가장 높은 점유율을 보였고, 규조류가 46종류로 28.4%로 다음으로 중요한 종군이었으며, 남조류(14종, 8.6%), 유글레나류(4종, 2.5%), 와편모조류(3종, 1.9%), 황색편모조류(3종, 1.9%), 은편모조류(2종류, 1.2%)순으로 나타나 녹조류가 가장 높게 조사되었다. 우점종은 남조류에서는 Microcystis aeruginosa, Microcystis incerta, Anabaena spiroides v.crassa가 관찰되었다. 규조류에서는 Fragilaria crotonensis, Aulacoseira granulata가 관찰되었으며, 녹조류에서는 Dictyosphaerium pulchellum, Eudorina elegans가 우점종으로 관찰되었다. 현존량은 최저 3,977 cellsㆍ㎖?¹에서 최고 61,855 cellsㆍ㎖?¹로 조사되었다. 종 다양성 지수와 균등도 지수, 우점도 지수는 각각 0.50~2.99, 0.15~0.81, 0.06~0.82로 조사되었다. 남한강과 북한강이 합쳐지는 팔당호 혼합 수계에서 식물플랑크톤 군집은 남한강 수계보다는 북한강에 영향을 더 받는 것으로 나타났다. 유해성 남조류는 여름철에 경안천 유업부에서 높게 나타나 팔당호 중심수계에 영향을 주는 것으로 나타났다.   To investigate the structure of the phytoplankton community in the Paldang lake in the summer, two surveys were conducted at six stations at the mouths of the Nothern Han River, the Southern Han River, and the Kyung-An stream, and in the Paldang lake in July 1999 and September 1999. Water temperature, transparency, dissolved oxygen, suspended solids, silicate, total phosphorus, and chlorophyll-a were measured to understand how the environmental parameters could affect the phytoplankton community. A total of 162 taxa of phytoplankton, including diatoms, dinoflagellates, green algae, and bule-green algae, were identified. The dominant species were Microcystis aeruginosa, Microcystis incerta, Anabaena spiroides v. crassa(blue-green algae), Fragilaria crotonensis, Aulacoseira granulata(diatoms), Dictyosphaerium pulchellum, and Eudorina elegans (green algae). The standing crop of the phytoplankton community ranged between 3,977 cellsㆍ㎖-1 and 61,855 cellㆍ㎖-1. The diversity, evenness, and dominant indices were ranged from 0.50 to 2.99, from 0.15 to 0.81, and from 0.07 to 0.82, respectively. In the area where waters from the Southern and Northern Han River are mixed, the phytoplankton community was appeared to be more influenced by the Northern Han River than by the Southern Han River. Concentatration of harmful bluegreen algae was hight at the mouth of the Kyung-An Stream, in the summer impling that the central area of the Paldang Lake was mainly affected by the Kyung-An Stream.

Seasonal Variations in Primary Productivity and Biomass of Phytoplankton in Geoje-Hansan Bay on the Southern Coast of Korea

김동영,이영재,강희윤,권기영,이원찬,곽정현 한국해양과학기술원 2019 Ocean science journal Vol.54 No.2

Phytoplankton constitutes an important dietary item of oysters in suspended longline aquaculture systems. Primary productivity and the community structure of phytoplankton, as well as hydrographic and nutritional conditions of the water column, were monitored monthly in Geoje-Hansan Bay on the southern coast of Korea between July 2013 and July 2014 to determine the seasonal variation patterns of productivity and structures of phytoplankton assemblages. All measured physicochemical and biological components exhibited temporal variabilities common to all four sampling sites within the bay system. The hydrographic features were characterized by a summer stratified and fall–winter well-mixed structure of the water column. Daily primary productivity in the bay (0.16–2.88 g C m–2 d–1) peaked in summer; it displayed a unimodal cycle, and the most dominant phytoplankton group shifted from diatoms to dinoflagellates. Canonical correspondence analysis, based on environmental factors and the phytoplankton community, enabled the identification of seasonal patterns of phytoplankton assemblage in relation to temporal variations of hydrographic and nutritional conditions. Results indicated that increase of the watercolumn stability and enhanced nutrient input by freshwater discharge during the summer monsoon and possible upward flux from bottom sediment led to the peaking primary productivity and diatom-dominated community during that time, supporting high annual productivity (371 g C m–2 yr–1). Our findings suggest that seasonal properties of hydrodynamics and nutritional conditions play a key role in determining the primary productivity and structuring of the phytoplankton community. Summer peaks in productivity and diatom dominance most likely ultimately determine oyster growth and the final success of aquaculture.

CO2와 수온 증가에 대한 봄철 저수온기 팔당호 식물플랑크톤군집 변화

이가람 ( Ka Ram Lee ),성은주 ( Eun Ju Sung ),박혜진 ( Hye Jin Park ),박채홍 ( Chae Hong Park ),박명환 ( Myung Hwan Park ),황순진 ( Soon Jin Hwang ) 한국하천호수학회(구 한국육수학회) 2013 생태와 환경 Vol.46 No.4

This study investigated the influence of temperature and CO2 increase on phytoplankton growth and community structure during cold water season (spring) in Lake Paldang, Korea. Four experimental treatments of temperature and CO2 manipulation were prepared in the laboratory batch culture: (1) Control; ambient low temperature (6±2.C) and low CO2 (air level, 400 mg L-1), (2) T1; low temperature and high CO2 (800 mg L-1), (3) T2; high temperature (20±2.C) and low CO2, (4) T3; high temperature and high CO2. Algal growth experiment was carried out for 10 days under the light intensity of 70 μmol m-2 s-1 (L:D=24 : 0). The level of pH decreased in both T1 and T3, due to dissolution of added CO2. The dominant phytoplankton species of ambient water, Cyclotella meneghiniana succeeded to Fragilaria capucina var. gracilis in high-temperature treatment groups (T2 and T3). Cyanobacteria were very rare at the beginning of the experiment, while Oscillatoria limnetica appeared in only high-temperature groups (T2 and T3) at 6~7th day. CO2 addition in ambient temperature (T1) induced the highest phytoplankton growth, and thereby producing the highest average cell density of 3.27±0.33 104 cells mL-1, followed by T2 (2.65±0.26 104 cells mL-1), T3 (2.09±0.16 104 cells mL-1), and Control (1.86±0.13 104 cells mL-1) (F=7.167, p=0.000). In summary, temperature increase changed the phytoplankton community structure and CO2 increase promoted the phytoplankton growth during the cold spring season in Lake Paldang, suggesting a potential effect of climate change on freshwater phytoplankton.

A consistent structure of phytoplankton communities across the warm-cold regions of the water mass on a meridional transect in the East/Japan Sea

Kwak, J.H.,Han, E.,Lee, S.H.,Park, H.J.,Kim, K.R.,Kang, C.K. Pergamon Press 2017 Deep-sea research. Part II, Topical studies in oce Vol.143 No.-

Three cruises were undertaken along a meridional transect in the East/Japan Sea (EJS) in spring (May 2007), summer (July 2009), and fall (October 2012) to determine the geographic variations in phytoplankton biomass and community composition. This study revealed a gradient of surface temperature and a fluctuation of hydrographic conditions along the transect. Although a subpolar front (SPF) formed between the warm- and cold-water masses (37-40<SUP>o</SUP>N), no significant differences in phytoplankton biomass and community composition were detected between the southern and northern parts of the EJS. These results disprove our initial hypothesis that different water masses may contain differently structured phytoplankton communities. In the present study, isothermal layers (@? 12<SUP>o</SUP>C) fluctuated over a depth of 50m in both warm- and cold-water masses, depending on the SPF. In contrast, the nitracline (i.e. 2.5μM nitrate isopleth) depth was recorded within a limited range of 20-40m in spring, 30-50m in summer, and 40-60m in fall. The chlorophyll a concentrations at the subsurface chlorophyll maxima (SCM) were significantly higher in spring and summer (356 +/- 233 and 270 +/- 182ngL<SUP>-1</SUP>, respectively) than in fall (117 +/- 89ngL<SUP>-1</SUP>). The relative contributions of individual phytoplankton groups to the depth-integrated chlorophyll a concentration conformed to the composition of the phytoplankton community in the SCM layer, showing a dominance of diatoms (58 +/- 19% in spring, 48 +/- 11% in summer, and 30 +/- 20% in fall). Canonical correspondence analysis revealed that the geographic structures of phytoplankton communities were strongly associated with the vertical structures of water temperature and nutrient concentration in the water column rather than with horizontal gradients of hydrographic conditions. Finally, our findings suggest that water column stability and light-nutrient availability in the euphotic zone play a key role in determining geographical consistency of the biomass and the community structure of phytoplankton in the EJS.

한강수계 주요 댐호의 식물플랑크톤 군집 세포내 화학양론

박혜경 ( Hae Kyung Park ) 한국물환경학회 2014 한국물환경학회지 Vol.30 No.6

Elemental cellular stoichiometry of natural phytoplankton communities was examined in six large dam reservoirs in the Han River system. Carbon (C) and nitrogen (N) contents of the phytoplankton-dominated seston from Lake Soyang was higher than that from other lakes. Phosphorus (P) content showed slight variations among six lakes in the range of 0.04~0.18 μmol P mg DW-1. The phosphorus concentrations of lake water showed obvious positive relationship with P and C contents of the phytoplankton-dominated seston. In all six lakes, N:P ratios and C:P ratios in the phytoplankton-dominated seston were more than 23 and 133 respectively, indicating the phytoplankton communities in six lakes have been exposed in phosphorus limited condition. The relative abundance of diatoms showed significant negative correlation with C, N, P contents of the phytoplankton-dominated seston and that of cyanobacteria showed significant positive correlation. Elemental stoichiometry of diatoms-dominated seston showed distinctive less content than that of cyanobacteria-dominated seston. The cellular N:P ratios of diatoms- and cyanobacteria-dominated seston indicated that both main classes of phytoplankton in six lakes are in phosphorus deficiency. Elemental stoichiometry of the phytoplankton-dominated seston in this study could be used for the further ecological stoichiometric studies in six lakes.

영광 안마군도 주변 해역 식물플랑크톤 군집의 계절 동태

주하연,송아영,박지혜,윤양호 한국환경생물학회 2022 환경생물 : 환경생물학회지 Vol.40 No.1

A survey was conducted to analyze seasonal dynamics of the phytoplankton community at 22 stations on the surface and bottom layers in the Anma Islands of Yeonggwang (AIY) in the southern West Sea, Korea from the spring of 2020 to the winter of 2021, using a marine survey vessel Ed Ocean. Based on the survey results, there were 87 phytoplankton species in 52 genera, diatoms accounted for 67.8%, dinoflagellates 26.5%, silicoflagellates 3.5%, and cryptomonads and euglenoids accounted for 1.1% each. By season, it was simple in spring and relatively varied in winter. The phytoplankton standing crop on the surface was low (28.8±30.1 cells mL-1) in summer and high (87.0±65.1 cells mL-1) in spring. In the phytoplankton community, diatoms showed a high share (over 80%) throughout the year, and Skeletonema costatum-ls was the dominant species with a dominance of more than 60% in spring and winter, and 34.6% and 24.2% in summer and autumn, respectively. The diversity expressing the characteristics of the community structure was high (2.79±0.45) in autumn and low (1.82±0.18) in spring, unlike the phytoplankton standing crop. However, the dominance was high at (0.86±0.08) in spring and low (0.44±0.13) in autumn. Based on the results of principal component analysis (PCA) using environmental and phytoplankton-related factors, it was estimated that the biological oceanographic environmental characteristics seen through the phytoplankton community in the AIY were dominated by nutrients supplied from open seawater and surface sediments by seawater mixing, such as tidal mixing. 서해 남부 안마군도 주변 해역 식물플랑크톤 군집의 계절 동태를 파악하기 위하여 2020년 봄부터 2021년 겨울까지 소형 해양조사선 에드오션호를 이용하여 21개 정점의 표층과 저층 해수를 대상으로 현장조사를 하였다. 결과, 출현한 식물플랑크톤 종은 52속 87종으로, 규조류가 67.8%, 와편모조류가 26.5%, 규질편모조류가 3.5%, 그리고 은편모조류 및 유글레나조류가 각 1.1%를 차지하였다. 계절별로 출현 종은 봄에 단순하였고, 겨울에 상대적으로 다양하였다. 표층 현존량은 여름 28.8±30.1 cells mL-1로 낮았고, 봄 87.0±65.1 cells mL-1로 높았다. 식물플랑크톤 군집은 연중 규조류가 80% 이상 높은 점유율을 나타내었고, 우점종은 Skeletonema costatum-ls가 봄과 겨울에 60% 이상 극우점을 보였고, 여름과 가을 각 34.6%와 24.2%로 최우점하였다. 군집구조 특성을 나타내는 다양도 지수는 현존량과 다르게 가을에 2.79±0.45로 높았고, 봄에 1.82±0.18로 낮았다. 그러나 우점도 지수는 봄에 0.86±0.08로 높았고, 가을에 0.44±0.13로 낮았다. 환경인자 및 식물플랑크톤 군집 관련 인자를 이용한 주성분 분석 결과, 식물플랑크톤 군집을 통해 본 안마군도 주변 해역의 생물해양학적 환경 특성은 상대적 개방 해역 및 조석 혼합 등 해수 혼합에 의한 해저 퇴적층에서 공급되는 영양염 등에 의해 지배되는 것으로 추정되었다.