Differences between Nearshore and Offshore Phytoplankton Communities in Lake Ontario

1987 ◽  
Vol 44 (12) ◽  
pp. 2155-2163 ◽  
Author(s):  
I. M. Gray
Keyword(s):  
Chlorophyll A ◽  
Phytoplankton Biomass ◽  
Algal Biomass ◽  
Phytoplankton Community ◽  
Seasonal Pattern ◽  
Principal Component ◽  
Lake Ontario ◽  
Dominant Group ◽  
Phytoplankton Communities ◽  
Eutrophic Species

Differences between nearshore and offshore phytoplankton biomass and composition were evident in Lake Ontario in 1982. Phytoplankton biomass was characterized by multiple peaks which ranged over three orders of magnitude. Perhaps as a consequence of the three times higher current velocities at the northshore station, phytoplankton biomass ranged from 0.09 to 9.00 g∙m−3 compared with 0.10 to 2.40 g∙m−3 for the midlake station. Bacillariophyceae was the dominant group at the northshore station until September when Cyanophyta contributed most to the biomass (83%). Although Bacillariophyceae was the principal component of the spring phytoplankton community at the midlake station, phytoflagellates (49%) and Chlorophyceae (25%) were responsible for summer biomass, with the Chlorophyceae expanding to 80% in the fall. The seasonal pattern of epilimnetic chlorophyll a correlated with temperature. While chlorophyll a concentrations were similar to values from 1970 and 1972, algal biomass had declined and a number of eutrophic species (Melosira binderana, Stephanodiscus tenuis, S. hantzschii var. pusilla, and S. alpinus) previously found were absent in 1982.

scholarly journals Vertical distribution of chlorophyll <I>a</I> concentration and phytoplankton community composition from in situ fluorescence profiles: a first database for the global ocean

2015 ◽  
Vol 7 (2) ◽  
pp. 261-273 ◽  
Author(s):  
R. Sauzède ◽  
H. Lavigne ◽  
H. Claustre ◽  
J. Uitz ◽  
C. Schmechtig ◽  
...  
Keyword(s):  
Chlorophyll Fluorescence ◽  
Chlorophyll A ◽  
Community Composition ◽  
Phytoplankton Biomass ◽  
Phytoplankton Community ◽  
Environmental Data ◽  
Global Ocean ◽  
Control Procedure ◽  
Chlorophyll A Concentration ◽  
Phytoplankton Community Composition

Abstract. In vivo chlorophyll a fluorescence is a proxy of chlorophyll a concentration, and is one of the most frequently measured biogeochemical properties in the ocean. Thousands of profiles are available from historical databases and the integration of fluorescence sensors to autonomous platforms has led to a significant increase of chlorophyll fluorescence profile acquisition. To our knowledge, this important source of environmental data has not yet been included in global analyses. A total of 268 127 chlorophyll fluorescence profiles from several databases as well as published and unpublished individual sources were compiled. Following a robust quality control procedure detailed in the present paper, about 49 000 chlorophyll fluorescence profiles were converted into phytoplankton biomass (i.e., chlorophyll a concentration) and size-based community composition (i.e., microphytoplankton, nanophytoplankton and picophytoplankton), using a method specifically developed to harmonize fluorescence profiles from diverse sources. The data span over 5 decades from 1958 to 2015, including observations from all major oceanic basins and all seasons, and depths ranging from the surface to a median maximum sampling depth of around 700 m. Global maps of chlorophyll a concentration and phytoplankton community composition are presented here for the first time. Monthly climatologies were computed for three of Longhurst's ecological provinces in order to exemplify the potential use of the data product. Original data sets (raw fluorescence profiles) as well as calibrated profiles of phytoplankton biomass and community composition are available on open access at PANGAEA, Data Publisher for Earth and Environmental Science. Raw fluorescence profiles: http://doi.pangaea.de/10.1594/PANGAEA.844212 and Phytoplankton biomass and community composition: http://doi.pangaea.de/10.1594/PANGAEA.844485

Effects of zooplankton grazing on phytoplankton communities in Mt Bold Reservoir, South Australia, using enclosures

1988 ◽  
Vol 39 (4) ◽  
pp. 503 ◽  
Author(s):  
CJ Merrick ◽  
GG Ganf
Keyword(s):  
Chlorophyll A ◽  
Selection Criteria ◽  
Phytoplankton Community ◽  
Food Selection ◽  
South Australia ◽  
Zooplankton Grazing ◽  
Multivariate Statistical ◽  
Phytoplankton Communities ◽  
Phytoplankton Size ◽  
Temporal Path

Enclosure experiments demonstrated that zooplankton grazing changed the composition of the phytoplankton community in Mt Bold Reservoir. Phytoplankton biomass as measured by chlorophyll a did not change within the enclosures but changed across the experiments in response to zooplankton grazing. The chlorophyll a : phaeophytin a ratio did not reflect zooplankton grazing activity. Phytoplankton species richness and diversity did not change but the frequencies of many individual phytoplankton taxa differed in response to zooplankton grazing. Neither taxonomic identity nor phytoplankton size as measured by greatest axial linear dimension and volume determined the susceptibility of a taxon to grazing. This suggests that other criteria are important in food selection, criteria which vary between experiments. Multivariate statistical techniques successfully differentiated the grazed and the ungrazed phytoplankton communities based on the different frequencies of the component taxa. There was an indication that, within the enclosures, zooplankton grazing advanced the phytoplankton community along a temporal path. Microzooplankton grazing was not examined in these experiments but there was evidence that it was significant.

scholarly journals Phytoplankton dynamics in contrasting early stage North Atlantic spring blooms: composition, succession, and potential drivers

2015 ◽  
Vol 12 (8) ◽  
pp. 2395-2409 ◽  
Author(s):  
C. J. Daniels ◽  
A. J. Poulton ◽  
M. Esposito ◽  
M. L. Paulsen ◽  
R. Bellerby ◽  
...  
Keyword(s):  
Primary Production ◽  
Chlorophyll A ◽  
North Atlantic ◽  
Phytoplankton Community ◽  
Spring Bloom ◽  
Early Stage ◽  
Biological Factors ◽  
Phytoplankton Composition ◽  
Bloom Formation ◽  
Phytoplankton Communities

Abstract. The spring bloom is a key annual event in the phenology of pelagic ecosystems, making a major contribution to the oceanic biological carbon pump through the production and export of organic carbon. However, there is little consensus as to the main drivers of spring bloom formation, exacerbated by a lack of in situ observations of the phytoplankton community composition and its evolution during this critical period. We investigated the dynamics of the phytoplankton community structure at two contrasting sites in the Iceland and Norwegian basins during the early stage (25 March–25 April) of the 2012 North Atlantic spring bloom. The plankton composition and characteristics of the initial stages of the bloom were markedly different between the two basins. The Iceland Basin (ICB) appeared well mixed down to >400 m, yet surface chlorophyll a (0.27–2.2 mg m−3) and primary production (0.06–0.66 mmol C m−3 d−1) were elevated in the upper 100 m. Although the Norwegian Basin (NWB) had a persistently shallower mixed layer (<100 m), chlorophyll a (0.58–0.93 mg m−3) and primary production (0.08–0.15 mmol C m−3 d−1) remained lower than in the ICB, with picoplankton (<2 μm) dominating chlorophyll a biomass. The ICB phytoplankton composition appeared primarily driven by the physicochemical environment, with periodic events of increased mixing restricting further increases in biomass. In contrast, the NWB phytoplankton community was potentially limited by physicochemical and/or biological factors such as grazing. Diatoms dominated the ICB, with the genus Chaetoceros (1–166 cells mL−1) being succeeded by Pseudo-nitzschia (0.2–210 cells mL−1). However, large diatoms (>10 μm) were virtually absent (<0.5 cells mL−1) from the NWB, with only small nano-sized (<5 μm) diatoms (i.e. Minidiscus spp.) present (101–600 cells mL−1). We suggest microzooplankton grazing, potentially coupled with the lack of a seed population of bloom-forming diatoms, was restricting diatom growth in the NWB, and that large diatoms may be absent in NWB spring blooms. Despite both phytoplankton communities being in the early stages of bloom formation, different physicochemical and biological factors controlled bloom formation at the two sites. If these differences in phytoplankton composition persist, the subsequent spring blooms are likely to be significantly different in terms of biogeochemistry and trophic interactions throughout the growth season, with important implications for carbon cycling and organic matter export.

Lack of Effect of Arsenic on Phytoplankton Communities in Different Nutrient Conditions

1983 ◽  
Vol 40 (2) ◽  
pp. 156-161 ◽  
Author(s):  
Dolores Planas ◽  
Alain Lamarche
Keyword(s):  
Organic Matter ◽  
Key Words ◽  
Chlorophyll A ◽  
Bottom Sediments ◽  
Phytoplankton Biomass ◽  
Canadian Shield ◽  
Inorganic Nutrients ◽  
Phytoplankton Communities ◽  
Nutrient Conditions

One-metre diameter plastic cylinders open to bottom sediments were used to investigate the effect of 30–40 μmol∙L−1 concentrations of arsenic on phytoplankton communities of the Canadian Shield. Dissolved nutrient-rich organic matter (trypticase soy broth) and inorganic nutrients [Formula: see text] were also added in the presence or absence of arsenic. Arsenic caused little change in phytoplankton biomass, measured as chlorophyll a or as biovolumes, in any of the cylinders during the 1st week of the experiment. Thereafter the biomass increased in cylinders enriched with organic matter and nutrients (with and without arsenic).Key words: arsenic, chlorophyll a, biomass, nutrients

Seasonal pattern and inferred phosphorus limitation of phytoplankton biomass in two tropical reservoirs in northern Australia

2000 ◽  
Vol 51 (1) ◽  
pp. 91 ◽  
Author(s):  
Simon A. Townsend
Keyword(s):  
Chlorophyll A ◽  
Total Phosphorus ◽  
Phytoplankton Biomass ◽  
Seasonal Pattern ◽  
Phosphorus Concentration ◽  
Wet Season ◽  
Temperate Lakes ◽  
Total Phosphorus Concentration ◽  
River Reservoir ◽  
Annual Range

Manton River Reservoir (MRR) and Darwin River Reservoir (DRR) are two small impoundments in the Australian wet/dry tropics. Over an eight-year period, chlorophyll a concentrations in the mixed layer averaged 3.6 µg L−1 in DRR, and 7.1 µg L−1 in MRR. The seasonal pattern of chlorophyll a at MRR was influenced by wet season wash-out (February average 4.8 µg L−1 ), and dry season destratification and nutrient enrichment of the surface waters (July average 8.4 mg L−1 ). In contrast, DRR exhibited near uniform chlorophyll a concentrations over the year. The seasonal patterns of DRR and MRR chlorophyll a are typical of tropical water bodies which tend to have a smaller annual range than temperate lakes, though this can be modified by significant wash-out. Empirical evidence suggests that the phytoplankton biomass of each reservoir is phosphorus limited, relative to the potential provided by other nutrients and light energy. This conclusion is based on a regression of total phosphorus and chlorophyll a concentrations of pooled DRR and MRR data (P < 0.001; r2 = 0.90), and the high total-nitrogen to total-phosphorus concentration ratios (by weight) of 50 and 37 in DRR and MRR, respectively. Annual chlorophyll a and total phosphorus concentrations for both reservoirs are in accord with the OECD regression for temperate lakes and reservoirs.

scholarly journals Evaluation of the Conditions of Mamberamo River Water with Biomass and Phytoplankton Community Approach

2021 ◽  
Vol 13 (1) ◽  
pp. 38
Author(s):  
Mirna Dwirastina ◽  
Dwi Atminarso
Keyword(s):  
Chlorophyll A ◽  
Phytoplankton Biomass ◽  
Phytoplankton Community ◽  
Nutrient Content ◽  
Coefficient Of Determination ◽  
Chemical Parameters ◽  
Phytoplankton Abundance ◽  
Community Approach ◽  
Phosphate Nitrate ◽  
Chlorophyll A Content

HighlightThe highest composition was Bacillariophyceae class and lowest was Cyanophyceae.Phytoplankton community abundance in waters is tightly related with nutrient content such as phosphate, nitrate, silicate, and other nutrients.Relation between abundance, biomass, and nutrients in Mamberamo river had the same pattern throughout February, May, and August in 2016.High biomass in an area related positively with phytoplankton abundance in its area.AbstractMemberamo River in Papua Province, that is a place of livelihood for the surrounding population, has a high biodiversity. This study aimed to provide information about the condition of the waters in the Mamberamo River by using biological and chemical parameters, namely community and phytoplankton biomass and chlorophyll-a content. The method used in determining the location was purposive random sampling based on differences in microhabitat that conducted in February, March, August, and October 2016. Phytoplankton observations were carried out through the method of sweeping Sediment Rafter (SR), and phytoplankton biomass obtained from chlorophyll-a. The results of this study showed three classes of phytoplankton were found, namely Bacillariophyceae, Chlorophyceae, and Cyanophyceae. The highest class of abundance was found in the river such as Bacillariophycea Chlorophyceae, and Cyanophyceae respectively. The chlorophyll-a concentration of phytoplankton biomass ranged from 2.01-548.73 mg/l and equation obtained from regression analysis between abundance and chlorophyll-a content was y = 1.2206 x – 0.7702 with a coefficient of determination r = 0.68. It could be concluded that the high phytoplankton biomass had a positive relationship with the chlorophyll-a content and the condition of the waters of the Mamberamo River is still categorized as good with good water fertility

scholarly journals Effect of silver nanoparticles on water quality and phytoplankton communities in fresh waterbody

2018 ◽  
Vol 9 (4) ◽  
pp. 185-190
Author(s):  
Thi Thu Huong Tran ◽  
Thi Thuy Duong ◽  
Trung Kien Nguyen ◽  
Thi Phuong Quynh Le ◽  
Duc Dien Nguyen ◽  
...  
Keyword(s):  
Water Quality ◽  
Silver Nanoparticles ◽  
Chlorophyll A ◽  
Environmental Variables ◽  
Phytoplankton Community ◽  
Chemical Reduction ◽  
Ammonium Phosphate ◽  
Uniform Size ◽  
Spherical Form ◽  
Phytoplankton Communities

This study aims to investigate the potential effects of environmental variables and the toxicity of nanosilver colloids synthesized by chemical reduction method on growth and development of phytoplankton community (the Microcystis genus dominance) in the eutrophication Tien lake water, Hanoi city, Vietnam. The variables analyzed including: physical (pH and Turbidity), chemical (content of NH4+, PO43- and silver metal), biological (content of Chlorophyll-a, cell density). The characteristic of nanomaterial was confirmed by using UV-visible spectrophotometer, TEM and HR-TEM methods. The obtained silver nanoparticles (AgNPs) showed that their spherical form and uniform size varied from 10 to 15 nm. The experimental results showed that the samples treated with AgNPs inhibition on growth against M. aeruginosa at concentration 1 mg/l after 8 days. The content of silver in aquarium water decreased from 1 mg/l (D0) to 0.8 mg/l (D8). The contents of chlorophyll-a of phytoplankton community, including Microcystis genus in samples exposed with AgNPs were declined from 11.27 ± 0.56g/L (D0) to 1.98 ± 0.37 g/L (D8) . The environmental variables such as: pH, temperature, dissolved oxygen, turbidity, ammonium, phosphate... in the experiment were below the limit of the Vietnam Standard 08:2015/MONRE for surface water quality. Mục đích của nghiên cứu này là khảo sát ảnh hưởng của vật liệu nano bạc tổng hợp bằng phương pháp khử hóa học đến sinh trưởng và phát triển của quần xã thực vật nổi (chủ yếu là chi Microcystis) trong nước hồ Tiền phú dưỡng, tại Hà Nội, Việt Nam. Các thông số phân tích bao gồm: thủy lý (pH và độ đục), hóa học (hàm lượng amoni, photphat và hàm lượng bạc kim loại), sinh học (hàm lượng chất diệp lục, mật độ tế bào). Đặc trưng của vật liệu được xác định bằng các phương pháp quang phổ UV-VIS, TEM và HR-TEM. Vật liệu nano bạc có dạng hình cầu, kích thước đồng nhất trong khoảng 10-15nm. Kết quả thử nghiệm sau 8 ngày cho thấy các mẫu có bổ sung vật liệu nano bạc ức chế sinh trưởng đối với vi khuẩn lam M. aeruginosa ở nồng độ 1mg/l. Hàm lượng bạc kim loại giảm từ 1 mg/l (ngày đầu tiên) xuống còn 0.8 mg/l (vào ngày cuối cùng). Sinh khối thực vật nổi trong đó có chi Microcystis trong mẫu xử lý với AgNPs đã giảm tương ứng từ 11.27 ± 0.56 g/L (ngày đầu tiên, D0) xuống 1.98 ± 0.37 g/L (ngày cuối cùng, D8). Các thông số môi trường của nước hồ đều nằm dưới giới hạn cho phép của QCVN 08:2015/BTNMT đối với chất lượng nước mặt.

scholarly journals Spring phytoplankton communities of the Labrador Sea (2005–2014): pigment signatures, photophysiology and elemental ratios

2017 ◽  
Vol 14 (5) ◽  
pp. 1235-1259 ◽  
Author(s):  
Glaucia M. Fragoso ◽  
Alex J. Poulton ◽  
Igor M. Yashayaev ◽  
Erica J. H. Head ◽  
Duncan A. Purdie
Keyword(s):  
Chlorophyll A ◽  
Community Composition ◽  
Phytoplankton Community ◽  
High Light ◽  
Labrador Sea ◽  
Total Chlorophyll ◽  
Phytoplankton Communities ◽  
Mixed Layers ◽  
Phytoplankton Group

Abstract. The Labrador Sea is an ideal region to study the biogeographical, physiological, and biogeochemical implications of phytoplankton community composition due to sharp transitions between distinct water masses across its shelves and central basin. We have investigated the multi-year (2005–2014) distributions of late spring and early summer (May to June) phytoplankton communities in the various hydrographic settings of the Labrador Sea. Our analysis is based on pigment markers (using CHEMTAX analysis), and photophysiological and biogeochemical characteristics associated with each phytoplankton community. Diatoms were the most abundant group, blooming first in shallow mixed layers of haline-stratified Arctic shelf waters. Along with diatoms, chlorophytes co-dominated at the western end of the section (particularly in the polar waters of the Labrador Current (LC)), whilst Phaeocystis co-dominated in the east (modified polar waters of the West Greenland Current (WGC)). Pre-bloom conditions occurred in deeper mixed layers of the central Labrador Sea in May, where a mixed assemblage of flagellates (dinoflagellates, prasinophytes, prymnesiophytes, particularly coccolithophores, and chrysophytes/pelagophytes) occurred in low-chlorophyll areas, succeeding to blooms of diatoms and dinoflagellates in thermally stratified Atlantic waters in June. Light-saturated photosynthetic rates and saturation irradiance levels were highest at stations where diatoms were the dominant phytoplankton group ( >  70 % of total chlorophyll a), as opposed to stations where flagellates were more abundant (from 40 up to 70 % of total chlorophyll a). Phytoplankton communities from the WGC (Phaeocystis and diatoms) had lower light-limited photosynthetic rates, with little evidence of photoinhibition, indicating greater tolerance to a high light environment. By contrast, communities from the central Labrador Sea (dinoflagellates and diatoms), which bloomed later in the season (June), appeared to be more sensitive to high light levels. Ratios of accessory pigments (AP) to total chlorophyll a (TChl a) varied according to phytoplankton community composition, with polar phytoplankton (cold-water related) having lower AP  :  TChl a. Polar waters (LC and WGC) also had higher and more variable particulate organic carbon (POC) to particulate organic nitrogen (PON) ratios, suggesting the influence of detritus from freshwater input, derived from riverine, glacial, and/or sea ice meltwater. Long-term observational shifts in phytoplankton communities were not assessed in this study due to the short temporal frame (May to June) of the data. Nevertheless, these results add to our current understanding of phytoplankton group distribution, as well as an evaluation of the biogeochemical role (in terms of C  :  N ratios) of spring phytoplankton communities in the Labrador Sea, which will assist our understanding of potential long-term responses of phytoplankton communities in high-latitude oceans to a changing climate.

scholarly journals Responses of Phytoplankton Communities in Selected Eutrophic Lakes to Variable Weather Conditions

Water ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1207 ◽  
Author(s):  
Tomasz Lenard ◽  
Wojciech Ejankowski ◽  
Małgorzata Poniewozik
Keyword(s):  
Chlorophyll A ◽  
Air Temperature ◽  
Vegetative Growth ◽  
Phytoplankton Biomass ◽  
Total Precipitation ◽  
Eutrophic Lakes ◽  
Growth Season ◽  
Mild Winter ◽  
Phytoplankton Communities ◽  
Total Phytoplankton

It is well-known that recent climatic changes have strongly affected aquatic ecosystems. In this study, we examined the complex factors determining the development of phytoplankton communities during the vegetative growth season in eutrophic lakes located in a temperate zone in eastern Poland. Our analysis enabled us to divide the data into two different periods: years with a cold winter and low total precipitation, and those with a mild winter and high total precipitation. The analysis showed that the soluble and total nitrogen content, concentration of chlorophyll a, total phytoplankton biomass, and biomasses of Cyanobacteria and Cryptophyceae were significantly higher in the vegetative growth season in the year after a mild winter, whereas the soluble and total phosphorus content and phytoplankton biodiversity were significantly lower in these years. Hence, climate warming indirectly led to the loss of biodiversity in the phytoplankton communities in the studied lakes of temperate zone. During this study, we also tested the effects of increases in air temperature and total precipitation on phytoplankton communities over short time periods (14 and 28 days). The results showed that the total phytoplankton biomass and the chlorophyll a concentration were only positively correlated with the air temperature. All of the features described in this study showed how sensitive lake ecosystems are to climatic fluctuations.

scholarly journals Phytoplankton biomass dynamics and environmental variables around the Rocas Atoll Biological Reserve, South Atlantic

2015 ◽  
Vol 63 (4) ◽  
pp. 443-454 ◽  
Author(s):  
Marina Cavalcanti Jales ◽  
Fernando Antônio do Nascimento Feitosa ◽  
Maria Luise Koening ◽  
Manuel de Jesus Flores Montes ◽  
Moacyr Cunha de Araújo Filho ◽  
...  
Keyword(s):  
Chlorophyll A ◽  
Mixed Layer ◽  
Environmental Variables ◽  
Phytoplankton Biomass ◽  
Inorganic Nitrogen ◽  
Principal Component ◽  
Inorganic Phosphorus ◽  
Mean Value ◽  
South Atlantic ◽  
Biological Reserve

Abstract The Rocas Atoll Biological Reserve is located in the Atlantic Ocean, at 3º 51' S and 33º 49' W. It lies 143 nautical miles from the City of Natal, Rio Grande do Norte (Brazil). The purpose of this study was to analyze the hydrology, water masses, currents and chlorophyll a content to determine the dynamics of phytoplankton biomass around the Rocas Atoll. Samples were collected in July 2010 in the area around the Atoll, using the Research Vessel Cruzeiro do Sul of the Brazilian Navy. Two transects were established according to the surface currents, one of which at the southeast of the Atoll (SE) and the other at norwest (NW). Three collection points were determined on each of these transects. Samples were collected at different depths (surface and DCM - Deep Chlorophyll Maximum) and different times (day and night). According to PCA (Principal Component Analysis), the nutrients analyzed, DIN (dissolved inorganic nitrogen), DIP (dissolved inorganic phosphorus) and silicate, were inversely correlated with temperature and dissolved oxygen. Most environmental variables showed a significant increase due to the turbulence on the Northwest transect. There was an increase in the concentration of chlorophyll a and nutrients when the temperature and oxygen in the mixed layer was reduced due to the influence of the SACW (South Atlantic Central Water). Despite the increase observed in some variables such as nutrient salts and chlorophyll a, the temperature in the mixed layer attained a mean value of 23.23 ºC due to the predominance of Tropical Water. The increase of the phytoplankton biomass on the NW transect was, therefore, caused by the "island effect" and not by upwelling.

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