Journal articles: 'Marine phytoplankton Phytoplankton populations'

1

Medlin, Linda K., Martin Lange, and Eva-Maria Nöthig. "Genetic diversity in the marine phytoplankton: a review and a consideration of Antarctic phytoplankton." Antarctic Science 12, no. 3 (September 2000): 325–33. http://dx.doi.org/10.1017/s0954102000000389.

Full text

Abstract:

Molecular analysis of phytoplankton population structure has lagged behind other groups and has usually been inferred from physiological data determined from relatively few clones. Nearly every physiological measurement has shown that no single clone of any phytoplankton species can be considered truly representative of that species. One important reason why studies of phytoplankton population structure are perhaps 20 or more years behind those of other organisms is because of the necessity to establish clonal cultures prior to genetic analysis and the inability to perform fine-scale sampling under most conditions. Isozyme analysis, performed for a few species, has revealed heterozygosity between populations. In addition, fingerprinting analyses, such as Random Amplified Polymorphic DNAs (RAPDs) or multi-locus probes, have shown that phytoplankton blooms are not mono-clonal, are highly diverse and isolates are related by geographic origin. In the Southern Ocean, only two studies have been made of the population structure of phytoplankton. The first, based on quantitative genetic analysis of morphometric features, suggests that there is sufficient genetic variation in populations of Thalassiosira tumida to allow speciation in terms of major shifts in morphology under conditions of continued directional selection. The second, using sequence data from the noncoding regions of the internal transcribed spacer region (ITS) in the ribosomal cistron as a molecular marker, shows that populations of Phaeocystis antarctica within continental water masses are homogenous with little evidence of population structure. Populations found within the Antarctic Circumpolar Current are genetically distinct from others, suggesting the currents also play an important role in determining population structure in phytoplankton populations.

APA, Harvard, Vancouver, ISO, and other styles

2

Guerrera, E., A. M. Cicero, M. Giani, and G. Lanzilli. "Flow Cytometry studies of marine phytoplankton populations." Giornale botanico italiano 127, no. 6 (January 1993): 1115–21. http://dx.doi.org/10.1080/11263509309429490.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Schrader, Astrid. "Microbial Suicide." Body & Society 23, no. 3 (July 31, 2017): 48–74. http://dx.doi.org/10.1177/1357034x17716523.

Full text

Abstract:

While unicellular microbes such as phytoplankton (marine algae) have long been considered immortal unless eaten by predators, recent research suggests that under specific conditions entire populations of phytoplankton actively kill themselves; their assumed atemporality is being revised as marine ecologists recognize phytoplankton’s important role in the global carbon cycle. Drawing on empirical research into programmed cell death in marine microbes, this article explores how, in their study of microbial death, scientists change not only our understanding of microbial temporality, but also reconstruct the relationship between life and death, biological individuality and assumptions about a natural teleology associated with bounded biological systems and genetic programmes. Reading this research together with a Derridean deconstruction of the limit between human and other animals with respect to death, this article explores how the deconstruction of individuality from within biology may suggest alternatives to our anthropocentric notion of time and embodiment.

APA, Harvard, Vancouver, ISO, and other styles

4

Thompson, Haydn Frank, Stephen Summers, Raif Yuecel, and Tony Gutierrez. "Hydrocarbon-Degrading Bacteria Found Tightly Associated with the 50–70 μm Cell-Size Population of Eukaryotic Phytoplankton in Surface Waters of a Northeast Atlantic Region." Microorganisms 8, no. 12 (December 9, 2020): 1955. http://dx.doi.org/10.3390/microorganisms8121955.

Full text

Abstract:

The surface of marine eukaryotic phytoplankton can harbour communities of hydrocarbon-degrading bacteria; however, this algal–bacterial association has, hitherto, been only examined with non-axenic laboratory cultures of micro-algae. In this study, we isolated an operationally-defined community of phytoplankton, of cell size 50–70 μm, from a natural community in sea surface waters of a subarctic region in the northeast Atlantic. Using MiSeq 16S rRNA sequencing, we identified several recognized (Alcanivorax, Marinobacter, Oleispira, Porticoccus, Thalassospira) and putative hydrocarbon degraders (Colwelliaceae, Vibrionaceae) tightly associated with the phytoplankton population. We combined fluorescence in situ hybridisation with flow-cytometry (FISH-Flow) to examine the association of Marinobacter with this natural eukaryotic phytoplankton population. About 1.5% of the phytoplankton population contained tightly associated Marinobacter. The remaining Marinobacter population were loosely associated with either eukaryotic phytoplankton cells or non-chlorophyll particulate material. This work is the first to show the presence of obligate, generalist and putative hydrocarbonoclastic bacteria associated with natural populations of eukaryotic phytoplankton directly from sea surface water samples. It also highlights the suitability of FISH-Flow for future studies to examine the spatial and temporal structure and dynamics of these and other algal–bacterial associations in natural seawater samples.

APA, Harvard, Vancouver, ISO, and other styles

5

Lévy, Marina, Oliver Jahn, Stephanie Dutkiewicz, Michael J. Follows, and Francesco d'Ovidio. "The dynamical landscape of marine phytoplankton diversity." Journal of The Royal Society Interface 12, no. 111 (October 2015): 20150481. http://dx.doi.org/10.1098/rsif.2015.0481.

Full text

Abstract:

Observations suggest that the landscape of marine phytoplankton assemblage might be strongly heterogeneous at the dynamical mesoscale and submesoscale (10–100 km, days to months), with potential consequences in terms of global diversity and carbon export. But these variations are not well documented as synoptic taxonomic data are difficult to acquire. Here, we examine how phytoplankton assemblage and diversity vary between mesoscale eddies and submesoscale fronts. We use a multi-phytoplankton numerical model embedded in a mesoscale flow representative of the North Atlantic. Our model results suggest that the mesoscale flow dynamically distorts the niches predefined by environmental contrasts at the basin scale and that the phytoplankton diversity landscape varies over temporal and spatial scales that are one order of magnitude smaller than those of the basin-scale environmental conditions. We find that any assemblage and any level of diversity can occur in eddies and fronts. However, on a statistical level, the results suggest a tendency for larger diversity and more fast-growing types at fronts, where nutrient supplies are larger and where populations of adjacent water masses are constantly brought into contact; and lower diversity in the core of eddies, where water masses are kept isolated long enough to enable competitive exclusion.

APA, Harvard, Vancouver, ISO, and other styles

6

Smriga, Steven, Vicente I. Fernandez, James G. Mitchell, and Roman Stocker. "Chemotaxis toward phytoplankton drives organic matter partitioning among marine bacteria." Proceedings of the National Academy of Sciences 113, no. 6 (January 22, 2016): 1576–81. http://dx.doi.org/10.1073/pnas.1512307113.

Full text

Abstract:

The microenvironment surrounding individual phytoplankton cells is often rich in dissolved organic matter (DOM), which can attract bacteria by chemotaxis. These “phycospheres” may be prominent sources of resource heterogeneity in the ocean, affecting the growth of bacterial populations and the fate of DOM. However, these effects remain poorly quantified due to a lack of quantitative ecological frameworks. Here, we used video microscopy to dissect with unprecedented resolution the chemotactic accumulation of marine bacteria around individualChaetoceros affinisdiatoms undergoing lysis. The observed spatiotemporal distribution of bacteria was used in a resource utilization model to map the conditions under which competition between different bacterial groups favors chemotaxis. The model predicts that chemotactic, copiotrophic populations outcompete nonmotile, oligotrophic populations during diatom blooms and bloom collapse conditions, resulting in an increase in the ratio of motile to nonmotile cells and in the succession of populations. Partitioning of DOM between the two populations is strongly dependent on the overall concentration of bacteria and the diffusivity of different DOM substances, and within each population, the growth benefit from phycospheres is experienced by only a small fraction of cells. By informing a DOM utilization model with highly resolved behavioral data, the hybrid approach used here represents a new path toward the elusive goal of predicting the consequences of microscale interactions in the ocean.

APA, Harvard, Vancouver, ISO, and other styles

7

Upadhyay, R. K., R. K. Naji, and N. Kumari. "Dynamical Complexity in Some Ecological Models: Effects of Toxin Production by Phytoplankton." Nonlinear Analysis: Modelling and Control 12, no. 1 (January 25, 2007): 123–38. http://dx.doi.org/10.15388/na.2007.12.1.14726.

Full text

Abstract:

We investigate dynamical complexities in two types of chaotic tri-trophic aquatic food-chain model systems representing a real situation in the marine environment. Phytoplankton produce chemical substances known as toxins to reduce grazing pressure by zooplankton [1]. The role of toxin producing phytoplankton (TPP) on the chaotic behavior in these food chain systems is investigated. Holling type I, II, and III functional response forms are considered to study the interference between phytoplankton and zooplankton populations in the presence of toxic chemical. Our study shows that chaotic dynamics is robust to changes in the rates of toxin release as well as the toxin release functions. The present study also reveals that the rate of toxin production by toxin producing phytoplankton plays an important role in controlling oscillations in the plankton system. The different mortality functions of zooplankton due to toxin producing phytoplankton have significant influence in controlling oscillations, coexistence, survival or extinction of the zooplankton population. Further studies are needed to ascertain if this defence mechanism suppresses chaotic dynamics in model aquatic systems.

APA, Harvard, Vancouver, ISO, and other styles

8

Ikram, Naheed, and Nafisa Shoaib. "Effects of pesticides on photosynthesis of marine phytoplankton." Bangladesh Journal of Botany 47, no. 4 (December 31, 2018): 1007–11. http://dx.doi.org/10.3329/bjb.v47i4.47401.

Full text

Abstract:

Toxicity of pesticides, namely chlorpyrifos, malathion, cypermethrin, lambda-cyhalothrin and buctril were tested on the photosynthetic behavior of marine phytoplankton. The phytoplankton population was exposed to 0.01, 0.03, 0.06 and 0.09 ppm of test pesticides. The toxicity of pesticides stands in the order of lambda-cyhalothrin > chlorpyrifos > buctril > malathion > cypermethrin. The most toxic pesticide was lambda-cyhalothrin having IC50 value of 0.014 ppm. Toxicity of cypermethrin was less on phytoplankton compared to others.

APA, Harvard, Vancouver, ISO, and other styles

9

Pichard, SL, ME Frischer, and JH Paul. "Ribulose bisphosphate carboxylase gene expression in subtropical marine phytoplankton populations." Marine Ecology Progress Series 101 (1993): 55–65. http://dx.doi.org/10.3354/meps101055.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Zheng, Yan Lin, and Zhuo Ying Lv. "Study on the Selective Grazing of Zooplankton in Plankton Ecosystem." Advanced Materials Research 864-867 (December 2013): 17–21. http://dx.doi.org/10.4028/www.scientific.net/amr.864-867.17.

Full text

Abstract:

Harmful algal blooms (Habs) caused great harm to the human environment. Habs occurrence was connected with other types of plankton. This relationship may be restrictive, and may also be promotional. Selectivity of zooplankton grazing has an important influence on the Habs. The behavior of zooplankton selective grazing was studied in the plankton ecosystem formed by three populations of nontoxic phytoplankton-toxic phytoplankton-zooplankton (NTP-TTP-Z) system. The selective grazing function of zooplankton on toxic phytoplankton and non-toxic phytoplankton was built based on Holling type IV functional response. Numerical simulation was given depending on the laboratory data. Results show that the models nicely explained the selective grazing behavior of zooplankton in the three species ecosystem, and provided key parameters for the marine ecosystem dynamics models.

APA, Harvard, Vancouver, ISO, and other styles

11

Krasovec, Marc, Rosalind E. M. Rickaby, and Dmitry A. Filatov. "Evolution of Mutation Rate in Astronomically Large Phytoplankton Populations." Genome Biology and Evolution 12, no. 7 (July 1, 2020): 1051–59. http://dx.doi.org/10.1093/gbe/evaa131.

Full text

Abstract:

Abstract Genetic diversity is expected to be proportional to population size, yet, there is a well-known, but unexplained lack of genetic diversity in large populations—the “Lewontin’s paradox.” Larger populations are expected to evolve lower mutation rates, which may help to explain this paradox. Here, we test this conjecture by measuring the spontaneous mutation rate in a ubiquitous unicellular marine phytoplankton species Emiliania huxleyi (Haptophyta) that has modest genetic diversity despite an astronomically large population size. Genome sequencing of E. huxleyi mutation accumulation lines revealed 455 mutations, with an unusual GC-biased mutation spectrum. This yielded an estimate of the per site mutation rate µ = 5.55×10−10 (CI 95%: 5.05×10−10 – 6.09×10−10), which corresponds to an effective population size Ne ∼ 2.7×106. Such a modest Ne is surprising for a ubiquitous and abundant species that accounts for up to 10% of global primary productivity in the oceans. Our results indicate that even exceptionally large populations do not evolve mutation rates lower than ∼10−10 per nucleotide per cell division. Consequently, the extreme disparity between modest genetic diversity and astronomically large population size in the plankton species cannot be explained by an unusually low mutation rate.

APA, Harvard, Vancouver, ISO, and other styles

12

Rivkin, R. B. "Carbon-14 labelling patterns of individual marine phytoplankton from natural populations." Marine Biology 89, no. 2 (1985): 135–42. http://dx.doi.org/10.1007/bf00392884.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

McCluskey, Christina S., Thomas C. J. Hill, Francesca Malfatti, Camille M. Sultana, Christopher Lee, Mitchell V. Santander, Charlotte M. Beall, et al. "A Dynamic Link between Ice Nucleating Particles Released in Nascent Sea Spray Aerosol and Oceanic Biological Activity during Two Mesocosm Experiments." Journal of the Atmospheric Sciences 74, no. 1 (January 1, 2017): 151–66. http://dx.doi.org/10.1175/jas-d-16-0087.1.

Full text

Abstract:

Abstract Emission rates and properties of ice nucleating particles (INPs) are required for proper representation of aerosol–cloud interactions in atmospheric models. Few investigations have quantified marine INP emissions, a potentially important INP source for remote oceanic regions. Previous studies have suggested INPs in sea spray aerosol (SSA) are linked to oceanic biological activity. This proposed link was explored in this study by measuring INP emissions from nascent SSA during phytoplankton blooms during two mesocosm experiments. In a Marine Aerosol Reference Tank (MART) experiment, a phytoplankton bloom was produced with chlorophyll-a (Chl a) concentrations reaching 39 μg L−1, while Chl a concentrations more representative of natural ocean conditions were obtained during the Investigation into Marine Particle Chemistry and Transfer Science (IMPACTS; peak Chl a of 5 μg L−1) campaign, conducted in the University of California, San Diego, wave flume. Dynamic trends in INP emissions occurred for INPs active at temperatures > −30°C. Increases in INPs active between −25° and −15°C lagged the peak in Chl a in both studies, suggesting a consistent population of INPs associated with the collapse of phytoplankton blooms. Trends in INP emissions were also compared to aerosol composition, abundances of microbes, and enzyme activity. In general, increases in INP concentrations corresponded to increases in organic species in SSA and the emissions of heterotrophic bacteria, suggesting that both microbes and biomolecules contribute to marine INP populations. INP trends were not directly correlated with a single biological marker in either study. Direct measurements of INP chemistry are needed to accurately identify particles types contributing to marine INP populations.

APA, Harvard, Vancouver, ISO, and other styles

14

Belgrano, A., M. Lima, and NC Stenseth. "Non-linear dynamics in marine-phytoplankton population systems." Marine Ecology Progress Series 273 (2004): 281–89. http://dx.doi.org/10.3354/meps273281.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Thakur, Nilesh Kumar, S. K. Tiwari, and Ranjit Kumar Upadhyay. "Harmful algal blooms in fresh and marine water systems: The role of toxin producing phytoplankton." International Journal of Biomathematics 09, no. 03 (February 25, 2016): 1650043. http://dx.doi.org/10.1142/s1793524516500431.

Full text

Abstract:

In this paper, we have investigated a model with three interacting species: non-toxic phytoplankton, toxic phytoplankton and zooplankton with Holling type II and III functional responses over the space and time. The role of toxin producing phytoplankton (TPP) has been studied. We have presented the theoretical analysis of pattern formation in spatially distributed population with local diffusion. The paper highlights the heterogeneity of HABs over space and time. The choice of parameter values and the functional response is important to study the effect of TPP, also it would depend more on the nonlinearity of the system. With the help of numerical simulations, we have observed the spatial and spatiotemporal patterns for plankton system. This study demonstrates that TPP plays an important role in controlling the dynamics. We have observed that prey’s anti-predator efforts promote predator switching. It has been found that high predation of TPP helps for the coexistence of toxic, non-toxic phytoplankton and zooplankton population.

APA, Harvard, Vancouver, ISO, and other styles

16

Teeling, H., B. M. Fuchs, D. Becher, C. Klockow, A. Gardebrecht, C. M. Bennke, M. Kassabgy, et al. "Substrate-Controlled Succession of Marine Bacterioplankton Populations Induced by a Phytoplankton Bloom." Science 336, no. 6081 (May 3, 2012): 608–11. http://dx.doi.org/10.1126/science.1218344.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Stolte, Willem, Tracy McCollin, Anna A. M. Noordeloos, and Roel Riegman. "Effect of nitrogen source on the size distribution within marine phytoplankton populations." Journal of Experimental Marine Biology and Ecology 184, no. 1 (November 1994): 83–97. http://dx.doi.org/10.1016/0022-0981(94)90167-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Sharoni, Shlomit, and Itay Halevy. "Nutrient ratios in marine particulate organic matter are predicted by the population structure of well-adapted phytoplankton." Science Advances 6, no. 29 (July 2020): eaaw9371. http://dx.doi.org/10.1126/sciadv.aaw9371.

Full text

Abstract:

A common assumption of a constant nitrogen-to-phosphorus ratio (N:P) of 16:1 in marine particulate organic matter (POM) appears to be invalidated by observations of major spatial variations in N:P. Two main explanations have been proposed. The first attributes the N:P variability to changes in the community composition of well-adapted phytoplankton. The second proposes that variability arises from physiological acclimation involving intracellular adjustments of nutrient allocation under nutrient deficiency. Using a model of phytoplankton physiology, observational datasets, and a review of laboratory culture results, we assess the mechanistic basis of N:P variability. We find that the taxonomic composition of well-adapted phytoplankton best explains observed variations in POM N:P. Furthermore, we show that acclimation to nutrient deficiency may be safely neglected when considering the effects of ecology on POM N:P. These findings provide insight into the controls on global variability in POM composition and average phytoplankton physiological performance in the oceans.

APA, Harvard, Vancouver, ISO, and other styles

19

Carić, Marina, Nenad Jasprica, Frano Kršinić, Ivica Vilibić, and Mirna Batistić. "Hydrography, nutrients, and plankton along the longitudinal section of the Ombla Estuary (south-eastern Adriatic)." Journal of the Marine Biological Association of the United Kingdom 92, no. 6 (February 6, 2012): 1227–42. http://dx.doi.org/10.1017/s002531541100213x.

Full text

Abstract:

Abundance and structure of phytoplankton and zooplankton, along with their relationship to hydrographic conditions were determined in the highly stratified estuary of the karstic Ombla River, south-eastern Adriatic. Sampling was carried out during 17 cruises within a one year period. River discharge lowered surface salinity and enriched the estuary with NO3 and SiO4. Nutrient ratios suggested that PO4 was the most likely limiting nutrient for phytoplankton growth in the estuary. Diatoms were present in low numbers and dominated the winter–early spring period. Dinoflagellates dominated from the end of May to August. Phytoplankton and zooplankton were composed mostly of marine species and their abundance decreased in seaward direction. Planktonic populations are controlled by the river runoff, temperature, salinity, nutrient concentrations and grazing. The results were consistent with the hypothesis that no algal blooms have been recorded due to short renewal time.

APA, Harvard, Vancouver, ISO, and other styles

20

Bonachela, J. A., S. D. Allison, A. C. Martiny, and S. A. Levin. "A model for variable phytoplankton stoichiometry based on cell protein regulation." Biogeosciences 10, no. 6 (June 27, 2013): 4341–56. http://dx.doi.org/10.5194/bg-10-4341-2013.

Full text

Abstract:

Abstract. The elemental ratios of marine phytoplankton emerge from complex interactions between the biotic and abiotic components of the ocean, and reflect the plastic response of individuals to changes in their environment. The stoichiometry of phytoplankton is, thus, dynamic and dependent on the physiological state of the cell. We present a theoretical model for the dynamics of the carbon, nitrogen and phosphorus contents of a phytoplankton population. By representing the regulatory processes controlling nutrient uptake, and focusing on the relation between nutrient content and protein synthesis, our model qualitatively replicates existing experimental observations for nutrient content and ratios. The population described by our model takes up nutrients in proportions that match the input ratios for a broad range of growth conditions. In addition, there are two zones of single-nutrient limitation separated by a wide zone of co-limitation. Within the co-limitation zone, a single point can be identified where nutrients are supplied in an optimal ratio. When different species compete, the existence of a wide co-limitation zone implies a more complex pattern of coexistence and exclusion compared to previous model predictions. However, additional comprehensive laboratory experiments are needed to test our predictions. Our model contributes to the understanding of the global cycles of oceanic nitrogen and phosphorus, as well as the elemental ratios of these nutrients in phytoplankton populations.

APA, Harvard, Vancouver, ISO, and other styles

21

Bonachela, J. A., S. D. Allison, A. C. Martiny, and S. A. Levin. "A model for variable phytoplankton stoichiometry based on cell protein regulation." Biogeosciences Discussions 10, no. 2 (February 21, 2013): 3241–79. http://dx.doi.org/10.5194/bgd-10-3241-2013.

Full text

Abstract:

Abstract. The elemental ratios of marine phytoplankton emerge from complex interactions between the biotic and abiotic components of the ocean, and reflect the plastic response of individuals to changes in their environment. The stoichiometry of phytoplankton is, thus, dynamic and dependent on the physiological state of the cell. We present a theoretical model for the dynamics of the carbon, nitrogen and phosphorus contents of a phytoplankton population. By representing the regulatory processes controlling nutrient uptake, and focusing on the relation between nutrient content and protein synthesis, our model qualitatively replicates existing experimental observations for nutrient content and ratios. The population described by our model takes up nutrients in proportions that match the input ratios for a broad range of growth conditions. In addition, there are two zones of single-nutrient limitation separated by a wide zone of co-limitation. Within the co-limitation zone, a single point can be identified where nutrients are supplied in an optimal ratio. The existence of a wide co-limitation zone affects the standard picture for species competing for nitrogen and phosphorus, which shows here a much richer pattern. However, additional comprehensive laboratory experiments are needed to test our predictions. Our model contributes to the understanding of the global cycles of oceanic nitrogen and phosphorus, as well as the elemental ratios of these nutrients in phytoplankton populations.

APA, Harvard, Vancouver, ISO, and other styles

22

Vanharanta, Mari, Samu Elovaara, Daniel J. Franklin, Kristian Spilling, and Tobias Tamelander. "Viability of pico- and nanophytoplankton in the Baltic Sea during spring." Aquatic Ecology 54, no. 1 (November 11, 2019): 119–35. http://dx.doi.org/10.1007/s10452-019-09730-3.

Full text

Abstract:

Abstract Phytoplankton cell death is an important process in marine food webs, but the viability of natural phytoplankton communities remains unexplored in many ecosystems. In this study, we measured the viability of natural pico- and nanophytoplankton communities in the central and southern parts of the Baltic Sea (55°21′ N, 17°06′ E–60°18′ N, 19°14′ E) during spring (4th–15th April 2016) to assess differences among phytoplankton groups and the potential relationship between cell death and temperature, and inorganic nutrient availability. Cell viability was determined by SYTOX Green cell staining and flow cytometry at a total of 27 stations representing differing hydrographic regimes. Three general groups of phytoplankton (picocyanobacteria, picoeukaryotes, and nanophytoplankton) were identified by cytometry using pigment fluorescence and light scatter characteristics. The picocyanobacteria and picoeukaryotes had significantly higher cell viability than the nanophytoplankton population at all depths throughout the study area. Viability correlated positively with the photosynthetic efficiency (Fv/Fm, maximum quantum yield of photosystem II) as measured on the total phytoplankton community. However, an anticipated correlation with dissolved organic carbon was not observed. We found that the abiotic factors suggested to affect phytoplankton viability in other marine ecosystems were not as important in the Baltic Sea, and other biotic processes, e.g. processes related to species succession could have a more pronounced role.

APA, Harvard, Vancouver, ISO, and other styles

23

Barton, AD, F. González Taboada, A. Atkinson, CE Widdicombe, and CA Stock. "Integration of temporal environmental variation by the marine plankton community." Marine Ecology Progress Series 647 (August 13, 2020): 1–16. http://dx.doi.org/10.3354/meps13432.

Full text

Abstract:

Theory and observations suggest that low frequency variation in marine plankton populations, or red noise, may arise through cumulative integration of white noise atmospheric forcing by the ocean and its amplification within food webs. Here, we revisit evidence for the integration of stochastic atmospheric variations by comparing the power spectra of time series of atmospheric and oceanographic conditions to the population dynamics of 150 plankton taxa at Station L4 in the Western English Channel. The power spectra of oceanographic conditions (sea surface temperature, surface nitrate) are redder than those of atmospheric forcing (surface wind stress, net heat fluxes) at Station L4. However, plankton populations have power spectral slopes across trophic levels and body sizes that are redder than atmospheric forcing but whiter than oceanographic conditions. While zooplankton have redder spectral slopes than phytoplankton, there is no significant relationship between power spectral slope and body size or generation length. Using a predator-prey model, we show that the whitening of plankton time series relative to oceanographic conditions arises from noisy plankton bloom dynamics in this strongly seasonal system. The model indicates that, for typical predator-prey interactions, where the predator is on average 10 times longer than the prey, grazing leads to a modest reddening of phytoplankton variability by their larger and longer lived zooplankton consumers. Our findings suggest that, beyond extrinsic forcing by the environment, predator-prey interactions play a role in influencing the power spectra of time series of plankton populations.

APA, Harvard, Vancouver, ISO, and other styles

24

Tsirtsis, G. E. "A simulation model for the description of a eutrophic system with emphasis on the microbial processes." Water Science and Technology 32, no. 9-10 (November 1, 1995): 189–96. http://dx.doi.org/10.2166/wst.1995.0684.

Full text

Abstract:

A mathematical model was constructed trying to describe the dynamics of a coastal eutrophic system, with emphasis on the processes of phytoplanktonic exudation and bacterial mineralization. The model is two-dimensional with two compartments, the one characteristic of eutrophication and the other one of oligotrophy. Five state variables were chosen characterizing eutrophication, phytoplankton, bacteria, dissolved organic carbon (DOC), nitrate and ammonia concentration. The nutrient and organic load from sewage outfalls was also estimated from data available for the city of Mytilini. For the evaluation of the model, data available for the coastal area of Mytilini, Lesvos were used, collected from April 1991 to December 1993. A general pattern of low values in winter and higher in summer was predicted for phytoplanktonic carbon, whereas bacterial populations showed a significant seasonality with low numbers in winter time and early spring and higher in late summer and autumn. The model indicated close dependence of bacterial and phytoplanktonic growth and emphasizes the importance of eutrophic conditions in the survival and growth of the marine microbial flora. This model seems to be a useful methodological tool for the evaluation of different scenaria concerning water quality in coastal management studies.

APA, Harvard, Vancouver, ISO, and other styles

25

Tchmyr, V. D., R. I. Lee, and M. I. Senicheva. "Determination of the growth rate and elimination of certain phytoplankton species and populations in the Sevastopol Bay (Black Sea)." Marine Biological Journal 4, no. 3 (September 30, 2019): 81–94. http://dx.doi.org/10.21072/mbj.2019.04.3.08.

Full text

Abstract:

The relevance of the study is determined by the key role of phytoplankton in the functioning of marine ecosystems, since unicellular algae carry out the primary production of organic matter in photosynthesis and form the first trophic link in the food chain. The tasks of the work are to determine the values of the net (apparent) growth rate of phytoplankton as a whole and of its constituent elements, including populations of certain species, and to study the possibility of estimating the rate of their actual growth and consumption based on regular short-period determinations of phytoplankton abundance and biomass in natural communities. For the determinations, we used both the previously obtained data of the decadal monitoring of the phytoplankton state in the coastal zone and the results of recent experiments. The decadal determinations performed during 2007 near the mouth of the Sevastopol Bay included measurements of phytoplankton abundance and biomass, as well as of chlorophyll a concentrations at intervals of several days, which made it possible to calculate the net specific biomass growth rate (apparent growth, k) according to its changes identified during this period. By comparing the abundance of certain species during short-period determinations, 29 values of the apparent growth were obtained for 9 mass species. The apparent growth, being the difference between actual growth and consumption, can be used to determine these values. Patterns linking the values of the apparent and actual growth of algae cells with their sizes were found in the experiments conducted by the dilution method. In our experiments, we adapted classical dilution method for the study of total phytoplankton to determine the functional parameters of certain species, which made it possible to find the linking patterns. Using the found patterns, we obtained 22 values of growth rate µ and consumption rate m for 7 mass phytoplankton species at the mouth of the Sevastopol Bay. Studies show that the growth rate of certain species of phytoplankton, whose cell volume is less then 1000 µm³, can reach values over 1 day−1. For algae with the cell volume exceeding 1500 µm³, the values of µ approach the values of k, and the values of m approach zero. For this group, the actual growth rate µ is taken to be equal to the apparent growth rate k, and the rate of consumption m is taken to be zero. In fact, in the natural population, small species are predominantly consumed in the upper illuminated layer, while the larger ones sink to the bottom or into deep horizons. This means that primarily phytoplankton populations with small cells are consumed, while populations with larger cells are not consumed. However, this conclusion is not consistent with the rates of apparent growth measured in situ, which include both positive and negative values for all populations, regardless of cell size. This contradiction is explained by the fact, that in the experiment, large cells dying off and sinking to the bottom of the vessel are taken into account on a par with living cells, and it hides the effect of elimination.

APA, Harvard, Vancouver, ISO, and other styles

26

Butterfield, Nicholas J. "Plankton ecology and the Proterozoic-Phanerozoic transition." Paleobiology 23, no. 2 (1997): 247–62. http://dx.doi.org/10.1017/s009483730001681x.

Full text

Abstract:

Most modern marine ecology is ultimately based on unicellular phytoplankton, yet most large animals are unable to graze directly on even relatively large net phytoplankton; the repackaging effected by herbivorous mesozooplankton thus represents a key link in marine metazoan food chains. Despite the deep taphonomic biases affecting plankton fossilization, there is a clear record of phytoplankton from at least 1800 m.y ago. Proterozoic plankton are represented by small-to medium-sized sphaeromorphic acritarchs and probably do not include many/most of the unusually large acritarchs that characterize the Neoproterozoic. The first significant shift in phytoplankton diversity was therefore the rapid radiation of small acanthomorphic acritarchs in the Early Cambrian. The coincidence of phytoplankton diversification with the Cambrian radiation of large animals points compellingly to an ecological linkage between the two, particularly in light of recently discovered filter-feeding mesozooplankton in the Early Cambrian. The introduction of planktic filter feeders would have established the second tier of the Eltonian pyramid, potentially setting off the “self-propagating mutual feedback system of diversification” now recognized as the Cambrian explosion (Stanley 1973, 1976).By consuming significant percentages of net phytoplankton and suspending it as animal biomass and non-aggregating fecal pellets, mesozooplankton cause a net reduction in export production; a general introduction of zooplankton would therefore have reduced carbon burial and moderated the bloom and bust cycle that must have characterized Proterozoic populations of net phytoplankton. The effect of added trophic levels in Early Cambrian ecosystems can be viewed as a serial application of the trophic cascade process observed in modern lakes, whereby the introduction of higher trophic levels determines the accumulation of plant biomass at the base of the system. As such, the major biogeochemical perturbations that mark the onset of the Phanerozoic might be considered a consequence, rather than a cause, of the Cambrian explosion; reduced C export due to zooplankton expansion explains the otherwise anomalous drop in δ13C at the base of the Tommotian.Cambrian acanthomorphic acritarchs likely derived from planktic leiosphaerids exposed to mesozooplanktic grazing pressure, the ornamentation effectively increasing vesicle size without compromising buoyancy or surface-area:volume ratios. Alternatively, they may represent an escape into the plankton through a miniaturization of the much larger Neoproterozoic acanthomorphs. An invasion of small benthic herbivores into the water column to exploit the phytoplankton accounts for the origin of the mesozooplankton and may have been the key innovation in the Cambrian explosion.

APA, Harvard, Vancouver, ISO, and other styles

27

Mayali, Xavier, Brian Palenik, and Ronald S. Burton. "Dynamics of marine bacterial and phytoplankton populations using multiplex liquid bead array technology." Environmental Microbiology 12, no. 4 (January 26, 2010): 975–89. http://dx.doi.org/10.1111/j.1462-2920.2004.02142.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Shiomoto, Akihiro, and Satsuki Matsumura. "Diel periodicity in dark uptake of ammonium by natural populations of marine phytoplankton." Journal of Plankton Research 15, no. 11 (1993): 1333–39. http://dx.doi.org/10.1093/plankt/15.11.1333.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Duforêt-Gaurier, Lucile, David Dessailly, William Moutier, and Hubert Loisel. "Assessing the Impact of a Two-Layered Spherical Geometry of Phytoplankton Cells on the Bulk Backscattering Ratio of Marine Particulate Matter." Applied Sciences 8, no. 12 (December 19, 2018): 2689. http://dx.doi.org/10.3390/app8122689.

Full text

Abstract:

The bulk backscattering ratio ( b b p ˜ ) is commonly used as a descriptor of the bulk real refractive index of the particulate assemblage in natural waters. Based on numerical simulations, we analyze the impact of modeled structural heterogeneity of phytoplankton cells on b b p ˜ . b b p ˜ is modeled considering viruses, heterotrophic bacteria, phytoplankton, organic detritus, and minerals. Three case studies are defined according to the relative abundance of the components. Two case studies represent typical situations in open ocean, oligotrophic waters, and phytoplankton bloom. The third case study is typical of coastal waters with the presence of minerals. Phytoplankton cells are modeled by a two-layered spherical geometry representing a chloroplast surrounding the cytoplasm. The b b p ˜ values are higher when structural heterogeneity is considered because the contribution of coated spheres to light backscattering is higher than homogeneous spheres. The impact of heterogeneity is; however, strongly conditioned by the hyperbolic slope ξ of the particle size distribution. Even if the relative abundance of phytoplankton is small (<1%), b b p ˜ increases by about 58% (for ξ = 4 and for oligotrophic waters), when the heterogeneity is taken into account, in comparison with a particulate population composed only of homogeneous spheres. As expected, heterogeneity has a much smaller impact (about 12% for ξ = 4 ) on b b p ˜ in the presence of suspended minerals, whose increased light scattering overwhelms that of phytoplankton.

APA, Harvard, Vancouver, ISO, and other styles

30

Suffrian, K., P. Simonelli, J. C. Nejstgaard, S. Putzeys, Y. Carotenuto, and A. N. Antia. "Microzooplankton grazing and phytoplankton growth in marine mesocosms with increased CO2 levels." Biogeosciences Discussions 5, no. 1 (January 31, 2008): 411–33. http://dx.doi.org/10.5194/bgd-5-411-2008.

Full text

Abstract:

Abstract. Microzooplankton grazing and algae growth responses to increasing pCO2 levels (350, 700 and 1050 μatm) were investigated in nitrate and phosphate fertilized mesocosms during the PeECE III experiment 2005. Grazing and growth rates were estimated by the dilution technique combined with taxon specific HPLC pigment analysis. Phytoplankton and microzooplankton composition were determined by light microscopy. Despite a range up to 3 times the present CO2 levels, there were no clear differences in any measured parameter between the different CO2 treatments. Thus, during the first 9 days of the experiment the algae community standing stock (SS), measured as chlorophyll a (Chl a), showed the highest instantaneous grow rates (0.02–0.99 d-1) and increased from ca 2–3 to 6–12 μg l−1, in all mesocosms. Afterwards the phytoplankton SS decreased in all mesocosms until the end of the experiment. The microzooplankton SS, that was mainly dinoflagellates and ciliates varied between 23 and 130 μg C l−1, peaking on day 13–15, apparently responding to the phytoplankton development. Instantaneous Chl a growth rates were generally higher than the grazing rates, indicating only a limited overall effect of microzooplankton grazing on the most dominant phytoplankton. Diatoms and prymnesiophytes were significantly grazed (14–43% of the SS d-1) only in the pre-bloom phase when they were in low numbers and in the post-bloom phase when they were already limited by low nutrients and/or virus lysis. The cyanobacteria populations appeared more effected by microzooplankton grazing, generally removing 20–65% of the SS d−1.

APA, Harvard, Vancouver, ISO, and other styles

31

Sun, Yanfeng, Yang Liu, Chao Wu, Xiaoting Fu, Congcong Guo, Liuyang Li, and Jun Sun. "Characteristics of Eukaryotic Plankton Communities in the Cold Water Masses and Nearshore Waters of the South Yellow Sea." Diversity 13, no. 1 (January 8, 2021): 21. http://dx.doi.org/10.3390/d13010021.

Full text

Abstract:

Eukaryotic plankton are important parts of the marine biome and play an important role in maintaining the stability of marine ecosystems. In order to characterize the eukaryotic plankton communities in the South Yellow Sea Cold Water Mass (CWM) and the South Yellow Sea nearshore waters (NW) in October 2019, Illumina high–throughput sequencing was performed using the 18S rDNA V9 region as the target gene. Environmental factors (depth, pH, salinity, temperature, Chl a, nitrate, nitrite, ammonium, silicate, phosphate) in two sea areas were measured, and their correlations with abundance and diversity of eukaryotic plankton were analyzed. A total of 807 species of plankton were identified, of which 663 species in 24 categories were from the CWM area, and 614 species in 26 categories were from NW. The total phytoplankton abundance in CWM waters was higher than that in NW. Dinophyta and Bacillariophyta were the most abundant phyla of phytoplankton in the two areas. Arthropoda and Cnidaria were the major zooplankton taxa. The dominant fungal population was mainly Basidiomycota. Both the CWM and NW have effects on dissolved inorganic nutrient concentrations and plankton abundance. Environmental factor correlation analysis showed that the concentration of dissolved inorganic nutrients within the CWM increased with water depth and the abundance of plankton gradually increased. Ammonium salts, nitrates, phosphates, silicates and water depth were important factors affecting phytoplankton growth. Phytoplankton abundance increased with increasing concentrations of inorganic nutrients. Bacillariophyta showed a strong positive correlation with silicates and depth. Depth and microscopic phytoplankton abundance were important factors influencing the structure of the zooplankton community.

APA, Harvard, Vancouver, ISO, and other styles

32

Sun, Yanfeng, Yang Liu, Chao Wu, Xiaoting Fu, Congcong Guo, Liuyang Li, and Jun Sun. "Characteristics of Eukaryotic Plankton Communities in the Cold Water Masses and Nearshore Waters of the South Yellow Sea." Diversity 13, no. 1 (January 8, 2021): 21. http://dx.doi.org/10.3390/d13010021.

Full text

Abstract:

Eukaryotic plankton are important parts of the marine biome and play an important role in maintaining the stability of marine ecosystems. In order to characterize the eukaryotic plankton communities in the South Yellow Sea Cold Water Mass (CWM) and the South Yellow Sea nearshore waters (NW) in October 2019, Illumina high–throughput sequencing was performed using the 18S rDNA V9 region as the target gene. Environmental factors (depth, pH, salinity, temperature, Chl a, nitrate, nitrite, ammonium, silicate, phosphate) in two sea areas were measured, and their correlations with abundance and diversity of eukaryotic plankton were analyzed. A total of 807 species of plankton were identified, of which 663 species in 24 categories were from the CWM area, and 614 species in 26 categories were from NW. The total phytoplankton abundance in CWM waters was higher than that in NW. Dinophyta and Bacillariophyta were the most abundant phyla of phytoplankton in the two areas. Arthropoda and Cnidaria were the major zooplankton taxa. The dominant fungal population was mainly Basidiomycota. Both the CWM and NW have effects on dissolved inorganic nutrient concentrations and plankton abundance. Environmental factor correlation analysis showed that the concentration of dissolved inorganic nutrients within the CWM increased with water depth and the abundance of plankton gradually increased. Ammonium salts, nitrates, phosphates, silicates and water depth were important factors affecting phytoplankton growth. Phytoplankton abundance increased with increasing concentrations of inorganic nutrients. Bacillariophyta showed a strong positive correlation with silicates and depth. Depth and microscopic phytoplankton abundance were important factors influencing the structure of the zooplankton community.

APA, Harvard, Vancouver, ISO, and other styles

33

McSTAY, D., R. MILNE, G. G. WRIGHT, and J. DUNN. "A single probe fibre optic fluorosensor for marine and freshwater measurements of phytoplankton populations." International Journal of Remote Sensing 16, no. 5 (March 20, 1995): 957–65. http://dx.doi.org/10.1080/01431169508954454.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Hama, Takeo, and Katsumi Yanagi. "Production and neutral aldose composition of dissolved carbohydrates excreted by natural marine phytoplankton populations." Limnology and Oceanography 46, no. 8 (November 2001): 1945–55. http://dx.doi.org/10.4319/lo.2001.46.8.1945.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Simmonds, Mark. "The case against tributyltin." Oryx 20, no. 4 (October 1986): 217–20. http://dx.doi.org/10.1017/s0030605300020238.

Full text

Abstract:

The use of paints containing tributyltin (TBT) to keep boat hulls clean is threatening marine life in some coastal regions, especially where boating for pleasure is popular. Research so far has shown that very low concentrations of the chemical have lethal or mutagenic effects on some marine invertebrates and stop the growth of phytoplankton. Legislation is being drawn up by many countries to control the use of these paints, but the author fears that it may be too little and too late for some populations of organisms.

APA, Harvard, Vancouver, ISO, and other styles

36

Vidal, Gonzalo, and Małgorzata Moczydłowska-Vidal. "Biodiversity, speciation, and extinction trends of Proterozoic and Cambrian phytoplankton." Paleobiology 23, no. 2 (1997): 230–46. http://dx.doi.org/10.1017/s0094837300016808.

Full text

Abstract:

The degradation-resistant organic-walled cell envelopes of acritarchs are the most abundant microfossils in Proterozoic and Cambrian rocks. These microfossils reveal diversity fluctuations that illuminate the nature of the record of primary producers near the Proterozoic/Phanerozoic boundary. Neoproterozoic radiations, some 1000–542 m.y. ago, reached levels comparable to those observed in the Cambrian Period. The microbiotas from rock successions from 13 Cambrian biochrons display significant fluctuations in the total number of microfossil taxa belonging to discrete microfossil assemblages. The assemblages reveal that Cambrian protist assemblages evolved over relatively short time spans, apparently out of low-diversity remnant populations after gradual declines in diversity. The characteristic microbiotas of the terminal Neoproterozoic and the Early, Middle, and Late Cambrian blossomed over relatively narrow time ranges, subsequently collapsing to nearly the initial levels. By virtue of the decreasing time spans involved in the late Vendian, Early, Middle, and Late Cambrian respectively, the tempo of specific turnover appears to have varied considerably. Speciation levels gradually decreased during Early and Middle Cambrian times and during Early Cambrian times were accompanied by rising levels of extinction. This latter feature seems to have reversed during Middle Cambrian times, lasting well into Late Cambrian times. Acritarchs were at the base of the marine trophic chain together with bacteria and other protists that are largely unrepresented in the fossil record. For this reason, the rise of diverse Cambrian protistan plankton must have been essential for early marine metazoan differentiation. Indeed, patterns of total diversity, speciation, and extinction of Cambrian acritarchs clearly mirror those of contemporaneous marine invertebrate faunas at the generic level.

APA, Harvard, Vancouver, ISO, and other styles

37

Andersen, Valerie, and Paul Nival. "Modelling of Phytoplankton Population Dynamics in an Enclosed Water Column." Journal of the Marine Biological Association of the United Kingdom 69, no. 3 (August 1989): 625–46. http://dx.doi.org/10.1017/s0025315400031027.

Full text

Abstract:

To understand the working of the marine pelagic ecosystem one needs to study the logical frame of the complex food web. This study is much easier in an enclosed water column than in the open sea where biological interactions are often concealed by physical events.

APA, Harvard, Vancouver, ISO, and other styles

38

Crickenberger, Sam, and David S. Wethey. "Reproductive physiology, temperature and biogeography: the role of fertilization in determining the distribution of the barnacle Semibalanus balanoides." Journal of the Marine Biological Association of the United Kingdom 98, no. 6 (April 17, 2017): 1411–24. http://dx.doi.org/10.1017/s0025315417000364.

Full text

Abstract:

Marine benthic populations are dependent on early life-history stages surviving multiple population bottlenecks. Failure at one or several of these bottlenecks can alter species’ patterns of distribution and abundance. The barnacle Semibalanus balanoides is found along temperate and sub-arctic shorelines of the Atlantic and Pacific Oceans. Over the past century the southern range limits of S. balanoides have shifted hundreds of kilometres poleward on both coasts of the Atlantic. Here we tested if temperature limits fertilization and used these data, along with those from previous studies, to create mechanistic biogeographic models to understand which potential population bottlenecks in the early life-history of S. balanoides influence its distribution and abundance. In the western Atlantic survival of new recruits is probably more important in setting the southern range limit than the effects of temperature on early life-history stages because fertilization, brooding and the probability of larval release matching phytoplankton availability were all predicted to be high near the historical range edge. Phytoplankton mismatch may partially explain the ephemeral nature of S. balanoides in some parts of the English Channel. Further south along the coast of France predicted brooding success was reduced in a pattern consistent with historical range shifts in this region. Within Galicia, Spain fertilization was predicted to be low near the southern limit, and likely plays an important role in setting this range edge. Mismatches between phytoplankton abundance and larval release in Galicia may further limit reproductive success within this region.

APA, Harvard, Vancouver, ISO, and other styles

39

Cermeño, Pedro, Emilio Marañín, Derek Harbour, Francisco G. Figueiras, Bibiana G. Crespo, María Huete-Ortega, Manuel Varela, and Roger P. Harris. "Resource levels, allometric scaling of population abundance, and marine phytoplankton diversity." Limnology and Oceanography 53, no. 1 (January 2008): 312–18. http://dx.doi.org/10.4319/lo.2008.53.1.0312.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Collins, S. "Comment on ''Effects of long-term high CO2 exposure on two species of coccolithophore'' by Müller et al. (2010)." Biogeosciences 7, no. 7 (July 19, 2010): 2199–202. http://dx.doi.org/10.5194/bg-7-2199-2010.

Full text

Abstract:

Abstract. Populations can respond to environmental change over tens or hundreds of generations by shifts in phenotype that can be the result of a sustained physiological response, evolutionary (genetic) change, shifts in community composition, or some combination of these factors. Microbes evolve on human timescales, and evolution may contribute to marine phytoplankton responses to global change over the coming decades. However, it is still unknown whether evolutionary responses are likely to contribute significantly to phenotypic change in marine microbial communities under high pCO2 regimes or other aspects of global change. Recent work by Müller et al. (2010) highlights that long-term responses of marine microbes to global change must be empirically measured and the underlying cause of changes in phenotype explained. Here, I briefly discuss how tools from experimental microbial evolution may be used to detect and measure evolutionary responses in marine phytoplankton grown in high CO2 environments and other environments of interest. I outline why the particular biology of marine microbes makes conventional experimental evolution challenging right now and make a case that marine microbes are good candidates for the development of new model systems in experimental evolution. I suggest that "black box" frameworks that focus on partitioning phenotypic change, such as the Price equation, may be useful in cases where direct measurements of evolutionary responses alone are difficult, and that such approaches could be used to test hypotheses about the underlying causes of phenotypic shifts in marine microbe communities responding to global change.

APA, Harvard, Vancouver, ISO, and other styles

41

Martin, Jennifer L., and Murielle M. LeGresley. "New phytoplankton species in the Bay of Fundy since 1995." ICES Journal of Marine Science 65, no. 5 (February 27, 2008): 759–64. http://dx.doi.org/10.1093/icesjms/fsn022.

Full text

Abstract:

Abstract Martin, J. L., and LeGresley, M. M. 2008. New phytoplankton species in the Bay of Fundy since 1995. – ICES Journal of Marine Science, 65: 759–764. A monitoring programme was initiated in 1987 to study phytoplankton populations in the Western Isles region of the Bay of Fundy, southwest New Brunswick. Samples are collected weekly from May through October, and monthly during the remaining months, to determine phytoplankton distribution and abundance at Brandy Cove, Lime Kiln Bay, Deadmans Harbour, the Wolves Islands, and mid-Passamaquoddy Bay. Since the programme was initiated, several previously absent or non-indigenous species have been found, suggesting that new species may have been introduced to the area. In order to establish a baseline for species indigenous to Bay of Fundy waters, we have taken a conservative approach and termed species reported for the first time in the Bay of Fundy system since 1995 as “new” species. New species include the following: (dinoflagellates) Alexandrium pseudogonyaulax, Amphidinium carterae, A. sphenoides, Ceratium macroceros, Polykrikos schwartzii, Preperidinium meunieri, Protoperidinium crassipes, and Pyrocystis lunata; (diatoms) Attheya septentrionalis, Attheya longicornis, Chaetoceros radicans, Cylindrotheca gracilis, Grammatophora serpentina, Lithodesmium undulatum, Mediopyxis helysia, Membraneis challengeri, Neodenticula seminae, Odontella sinensis, Proboscia eumorpha, Pseudo-nitzschia subpacifica, Pseudo-nitzschia fraudulenta, and Thalassiosira punctigera.

APA, Harvard, Vancouver, ISO, and other styles

42

Hirata, T., N. J. Hardman-Mountford, R. J. W. Brewin, J. Aiken, R. Barlow, K. Suzuki, T. Isada, et al. "Synoptic relationships quantified between surface Chlorophyll-a and diagnostic pigments specific to phytoplankton functional types." Biogeosciences Discussions 7, no. 5 (September 1, 2010): 6675–704. http://dx.doi.org/10.5194/bgd-7-6675-2010.

Full text

Abstract:

Abstract. Error-quantified, synoptic-scale relationships between chlorophyll-a (Chla) and phytoplankton pigment groups at the sea surface are presented. A total of nine pigment groups were considered to represent nine phytoplankton functional types (PFTs) including microplankton, nanoplankton, picoplankton, diatoms, dinoflagellates, green algae, picoeukaryotes, prokaryotes and Prochlorococcus sp. The observed relationships between Chla and pigment groups were well-defined at the global scale to show that Chla can be used as an index of not only phytoplankton abundance but also community structure; large (micro) phytoplankton monotonically increase as Chla increases, whereas the small (pico) phytoplankton community generally decreases. Within these relationships, we also found non-monotonic variations with Chla for certain pico-plankton (pico-eukaryotes, Prokaryotes and Prochlorococcus sp.) and for Green Algae and nano-sized phytoplankton. The relationships were quantified with a least-square fitting approach in order to estimate the PFTs from Chla alone. The estimated uncertainty of the relationships quantified depends on both phytoplankton types and Chla concentration. Maximum uncertainty over all groups (34.7% Chla) was found from diatom at approximately Chla = 1.07 mg m−3. However, the mean uncertainty of the relationships over all groups was 5.8 [% Chla] over the entire Chla range observed (0.02 < Chla < 6.84 mg m−3). The relationships were applied to SeaWiFS satellite Chla data from 1998 to 2009 to show the global climatological fields of the surface distribution of PFTs. Results show that microplankton are present in the mid and high latitudes, constituting ~9.0 [% Chla] of the phytoplankton community at the global surface, in which diatoms explain ~6.0 [% Chla]. Nanoplankton are ubiquious throught much of the global surface oceans except subtropical gyres, acting as a background population, constituting ~44.2 [% Chla]. Picoplankton are mostly limited in subtropical gyres, constituting ~46.8 [% Chla] globally, in which prokaryotes are the major species explaining 32.3 [% Chla] (prochlorococcus sp. explaining 21.5 [% Chla]), while pico-eukaryotes are notably abundant in the Southern Pacific explaining ~14.5 [% Chla]. These results may be used to constrain or validate global marine ecosystem models.

APA, Harvard, Vancouver, ISO, and other styles

43

Zamora-Ley, Ingrid M., Piero R. Gardinali, and Frank J. Jochem. "Assessing the effects of Irgarol 1051 on marine phytoplankton populations in Key Largo Harbor, Florida." Marine Pollution Bulletin 52, no. 8 (August 2006): 935–41. http://dx.doi.org/10.1016/j.marpolbul.2005.12.010.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Štrojsová, Alena, and Sonya T. Dyhrman. "Cell-specific β-N-acetylglucosaminidase activity in cultures and field populations of eukaryotic marine phytoplankton." FEMS Microbiology Ecology 64, no. 3 (April 21, 2008): 351–61. http://dx.doi.org/10.1111/j.1574-6941.2008.00479.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Alcaraz, M., E. Saiz, C. Marrase, and D. Vaque. "Effects of turbulence on the development of phytoplankton biomass and copepod populations in marine microcosms." Marine Ecology Progress Series 49 (1988): 117–25. http://dx.doi.org/10.3354/meps049117.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

McCluskey, Christina S., Thomas C. J. Hill, Camille M. Sultana, Olga Laskina, Jonathan Trueblood, Mitchell V. Santander, Charlotte M. Beall, et al. "A Mesocosm Double Feature: Insights into the Chemical Makeup of Marine Ice Nucleating Particles." Journal of the Atmospheric Sciences 75, no. 7 (July 1, 2018): 2405–23. http://dx.doi.org/10.1175/jas-d-17-0155.1.

Full text

Abstract:

Abstract The abundance of atmospheric ice nucleating particles (INPs) is a source of uncertainty for numerical representation of ice-phase transitions in mixed-phase clouds. While sea spray aerosol (SSA) exhibits less ice nucleating (IN) ability than terrestrial aerosol, marine INP emissions are linked to oceanic biological activity and are potentially an important source of INPs over remote oceans. Inadequate knowledge of marine INP identity limits the ability to parameterize this complex INP source. A previous manuscript described abundances of marine INPs in relation to several aerosol composition and ocean biology observations during two laboratory mesocosm experiments. In this study, the abundances and chemical and physical properties of INPs found during the same mesocosm experiments were directly probed in SSA, seawater, and surface microlayer samples. Two unique marine INP populations were found: 1) dissolved organic carbon INPs are suggested to be composed of IN-active molecules, and 2) particulate organic carbon INPs are attributed as intact cells or IN-active microbe fragments. Both marine INP types are likely to be emitted into SSA following decay of phytoplankton biomass when 1) the surface microlayer is significantly enriched with exudates and cellular detritus and SSA particles are preferentially coated with IN-active molecules or 2) diatom fragments and bacteria are relatively abundant in seawater and therefore more likely transferred into SSA. These findings inform future efforts for incorporating marine INP emissions into numerical models and motivate future studies to quantify specific marine molecules and isolate phytoplankton, bacteria, and other species that contribute to these marine INP types.

APA, Harvard, Vancouver, ISO, and other styles

47

Keller, Maureen D., Patricia A. Matrai, Ronald P. Kiene, and Wendy K. Bellows. "Responses of coastal phytoplankton populations to nitrogen additions: dynamics of cell-associated dimethylsulfoniopropionate (DMSP), glycine betaine (GBT), and homarine." Canadian Journal of Fisheries and Aquatic Sciences 61, no. 5 (May 1, 2004): 685–99. http://dx.doi.org/10.1139/f04-058.

Full text

Abstract:

Dimethylsulfoniopropionate (DMSP) and glycine betaine (GBT) are organic osmolytes abundant in many marine phytoplankton. Herein, we field tested for the first time the hypothesis that GBT production might be favored over DMSP in natural phytoplankton populations growing in high-N environments or when N is added to a system. Concentrations of particulate DMSP (DMSPp; 1545 nmol·L1) were equal to, or greater than, concentrations of particulate GBT (GBTp; 015 nmol·L1) in the upper water column. Homarine, another N-containing osmolyte, was detected at lower levels in all samples. These are the first reported values of GBTp, and homarine in seawater. During N enrichment experiments, no consistent pattern of response in the DMSP pool resulted. Under N stress, nitrate addition either caused DMSP to be released but without an equivalent increase in GBT or DMSP dynamics were not affected but GBT increased. In populations under less N stress, GBT levels were similar to those of DMSPp throughout the experiments. Homarine levels remained low at all times. We conclude that no simple switch between DMSP and GBT occurs as a function of N availability in natural populations. Variable responses to N supply probably resulted from differences in species composition and physiological state of the populations present.

APA, Harvard, Vancouver, ISO, and other styles

48

Neufeld, Josh D., Rich Boden, Hélène Moussard, Hendrik Schäfer, and J. Colin Murrell. "Substrate-Specific Clades of Active Marine Methylotrophs Associated with a Phytoplankton Bloom in a Temperate Coastal Environment." Applied and Environmental Microbiology 74, no. 23 (October 10, 2008): 7321–28. http://dx.doi.org/10.1128/aem.01266-08.

Full text

Abstract:

ABSTRACT Marine microorganisms that consume one-carbon (C1) compounds are poorly described, despite their impact on global climate via an influence on aquatic and atmospheric chemistry. This study investigated marine bacterial communities involved in the metabolism of C1 compounds. These communities were of relevance to surface seawater and atmospheric chemistry in the context of a bloom that was dominated by phytoplankton known to produce dimethylsulfoniopropionate. In addition to using 16S rRNA gene fingerprinting and clone libraries to characterize samples taken from a bloom transect in July 2006, seawater samples from the phytoplankton bloom were incubated with 13C-labeled methanol, monomethylamine, dimethylamine, methyl bromide, and dimethyl sulfide to identify microbial populations involved in the turnover of C1 compounds, using DNA stable isotope probing. The [13C]DNA samples from a single time point were characterized and compared using denaturing gradient gel electrophoresis (DGGE), fingerprint cluster analysis, and 16S rRNA gene clone library analysis. Bacterial community DGGE fingerprints from 13C-labeled DNA were distinct from those obtained with the DNA of the nonlabeled community DNA and suggested some overlap in substrate utilization between active methylotroph populations growing on different C1 substrates. Active methylotrophs were affiliated with Methylophaga spp. and several clades of undescribed Gammaproteobacteria that utilized methanol, methylamines (both monomethylamine and dimethylamine), and dimethyl sulfide. rRNA gene sequences corresponding to populations assimilating 13C-labeled methyl bromide and other substrates were associated with members of the Alphaproteobacteria (e.g., the family Rhodobacteraceae), the Cytophaga-Flexibacter-Bacteroides group, and unknown taxa. This study expands the known diversity of marine methylotrophs in surface seawater and provides a comprehensive data set for focused cultivation and metagenomic analyses in the future.

APA, Harvard, Vancouver, ISO, and other styles

49

Fauzan, M., Sofyan Husein Siregar, and Syafruddin Nasution. "EFFECT OF DIFFERENT TYPES OF FERTILIZER ON THE GROWTH OF MARINE PHYTOPLANKTON POPULATION Chlorella vulgaris." Asian Journal of Aquatic Sciences 4, no. 1 (April 7, 2021): 65–72. http://dx.doi.org/10.31258/ajoas.4.1.65-72.

Full text

Abstract:

This research was conducted on October 13-26, 2019 in the Regional Technical Implementation Unit of the Seawater and Brackish Aquaculture Fisheries Office (UPTD BPBALP Teluk Buo), West Sumatra. This study aims to determine the effect of applying different types of fertilizers to the growth of Chlorella vulgaris microalgae populations on laboratory scale culture. The method used in this study was an experimental method in the laboratory using a completely randomized design (CRD) one factor, namely the difference in fertilizer types with 3 (three) replications. Fertilizers used are Walne fertilizer, ZA (Zwavelzure Ammoniak) and TSP (Triple Super Phosphate). The testing organism in this study was phytoplankton C. vulgaris. The container used was a glass jar (3 liter capacity). The parameters measured in this study include absolute growth, relative growth, specific growth, self-doubling time and water quality. The results of this study indicate that the best type of fertilizer for C.vulgaris population growth was TSP fertilizer, followed by ZA fertilizer and the lowest in Walne fertilizer.

APA, Harvard, Vancouver, ISO, and other styles

50

Cyronak, Tyler, Erin O’Reilly, Peter A. Lee, and Giacomo R. DiTullio. "In situ determination of cellular DMSP and pigment quotas in a Prorocentrum minimum bloom near the Falkland Islands." Advances in Oceanography and Limnology 5, no. 2 (October 16, 2014): 123. http://dx.doi.org/10.4081/aiol.2014.5353.

Full text

Abstract:

Marine phytoplankton play critical roles in the biogeochemistry of open and coastal oceans. However, the impact that individual species have on an ecosystem-wide scale can strongly depend on the production of cellular compounds, especially those that are climatically active such as dimethylsulfide (DMS). Herein, we use sorting flow cytometry to separate a distinct phytoplankton population from four samples taken along the Patagonian shelf near the Falkland Islands. Morphological, genetic, and biochemical analyses demonstrated that three of the sorted samples were dominated by a bloom of the dinoflagellate Prorocentrum minimum. Cellular quotas of the DMS-precursor dimethylsulfoniopropionate (DMSP) ranged from 1.23–4.11 pg cell−1 in the same population at different sampling stations. Causes of this variability may be due to different growth stages of the P. minimum bloom or changes in other environmental variables. Overall, in situ intracellular DMSP concentrations were lower than what would be expected based on previous, culture-based measurements. We demonstrate the difficulties inherent in sorting individual phytoplankton species from natural samples in order to determine in situ species-specific cellular quotas of important biogeochemical compounds.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Marine phytoplankton Phytoplankton populations'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles