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  • 2010-2014  (84)
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  • 1
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    PANGAEA
    In:  Supplement to: Van de Waal, Dedmer B; John, Uwe; Ziveri, Patrizia; Reichart, Gert-Jan; Hoins, Mirja; Sluijs, Appy; Rost, Björn (2013): Ocean Acidification Reduces Growth and Calcification in a Marine Dinoflagellate. PLoS ONE, 8(6), e65987, https://doi.org/10.1371/journal.pone.0065987
    Publication Date: 2023-08-03
    Description: Ocean acidification is considered a major threat to marine ecosystems and may particularly affect calcifying organisms such as corals, foraminifera and coccolithophores. Here we investigate the impact of elevated pCO2 and lowered pH on growth and calcification in the common calcareous dinoflagellate Thoracosphaera heimii. We observe a substantial reduction in growth rate, calcification and cyst stability of T. heimii under elevated pCO2. Furthermore, transcriptomic analyses reveal CO2 sensitive regulation of many genes, particularly those being associated to inorganic carbon acquisition and calcification. Stable carbon isotope fractionation for organic carbon production increased with increasing pCO2 whereas it decreased for calcification, which suggests interdependence between both processes. We also found a strong effect of pCO2 on the stable oxygen isotopic composition of calcite, in line with earlier observations concerning another T. heimii strain. The observed changes in stable oxygen and carbon isotope composition of T. heimii cysts may provide an ideal tool for reconstructing past seawater carbonate chemistry, and ultimately past pCO2. Although the function of calcification in T. heimii remains unresolved, this trait likely plays an important role in the ecological and evolutionary success of this species. Acting on calcification as well as growth, ocean acidification may therefore impose a great threat for T. heimii.
    Keywords: Calculated; Carbon, inorganic, particulate, per cell; Carbon, organic, particulate, per cell; Carbon dioxide; Cysts; Fractionation of calcite; Fractionation of organic carbon; Growth rate; Mediterranean Sea Acidification in a Changing Climate; MedSeA; Ratio; Treatment; δ18O, calcite; δ18O, dissolved inorganic carbon
    Type: Dataset
    Format: text/tab-separated-values, 144 data points
    Location Call Number Limitation Availability
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  • 2
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    PANGAEA
    In:  Supplement to: Hoppe, Clara Jule Marie; Langer, Gerald; Rokitta, Sebastian D; Wolf-Gladrow, Dieter A; Rost, Björn (2012): Implications of observed inconsistencies in carbonate chemistry measurements for ocean acidification studies. Biogeosciences, 9, 2401-2405, https://doi.org/10.5194/bg-9-2401-2012
    Publication Date: 2023-11-25
    Description: The growing field of ocean acidification research is concerned with the investigation of organism responses to increasing pCO2 values. One important approach in this context is culture work using seawater with adjusted CO2 levels. As aqueous pCO2 is difficult to measure directly in small-scale experiments, it is generally calculated from two other measured parameters of the carbonate system (often AT, CT or pH). Unfortunately, the overall uncertainties of measured and subsequently calculated values are often unknown. Especially under high pCO2, this can become a severe problem with respect to the interpretation of physiological and ecological data. In the few datasets from ocean acidification research where all three of these parameters were measured, pCO2 values calculated from AT and CT are typically about 30% lower (i.e. ~300 µatm at a target pCO2 of 1000 µatm) than those calculated from AT and pH or CT and pH. This study presents and discusses these discrepancies as well as likely consequences for the ocean acidification community. Until this problem is solved, one has to consider that calculated parameters of the carbonate system (e.g. pCO2, calcite saturation state) may not be comparable between studies, and that this may have important implications for the interpretation of CO2 perturbation experiments.
    Keywords: Alkalinity, total; Carbon dioxide; EPOCA; European Project on Ocean Acidification; Mediterranean Sea Acidification in a Changing Climate; MedSeA; Method comment; pH; Phosphate; Salinity; Silicate; Temperature, water; Type
    Type: Dataset
    Format: text/tab-separated-values, 197 data points
    Location Call Number Limitation Availability
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  • 3
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    PANGAEA
    In:  Supplement to: Tortell, Philippe Daniel; Trimborn, Scarlett; Li, Y; Rost, Björn; Payne, Christopher D (2010): Inorganic carbon utilization by Ross Sea phytoplankton across natural and experimental CO2 gradients. Journal of Phycology, 46(3), 433-443, https://doi.org/10.1111/j.1529-8817.2010.00839.x
    Publication Date: 2023-12-12
    Description: We present results from a field study of inorganic carbon (C) acquisition by Ross Sea phytoplankton during Phaeocystis-dominated early season blooms. Isotope disequilibrium experiments revealed that HCO3- was the primary inorganic C source for photosynthesis in all phytoplankton assemblages. From these experiments, we also derived relative enhancement factors for HCO3-/CO2 interconversion as a measure of extracellular carbonic anhydrase activity (eCA). The enhancement factors ranged from 1.0 (no apparent eCA activity) to 6.4, with an overall mean of 2.9. Additional eCA measurements, made using membrane inlet mass spectrometry (MIMS), yielded activities ranging from 2.4 to 6.9 U/[mg chl a] (mean 4.1). Measurements of short-term C-fixation parameters revealed saturation kinetics with respect to external inorganic carbon, with a mean half-saturation constant for inorganic carbon uptake (K1/2) of ~380 mM. Comparison of our early springtime results with published data from late-season Ross Sea assemblages showed that neither HCO3- utilization nor eCA activity was significantly correlated to ambient CO2 levels or phytoplankton taxonomic composition. We did, however, observe a strong negative relationship between surface water pCO2 and short-term 14C-fixation rates for the early season survey. Direct incubation experiments showed no statistically significant effects of pCO2 (10 to 80 Pa) on relative HCO3- utilization or eCA activity. Our results provide insight into the seasonal regulation of C uptake by Ross Sea phytoplankton across a range of pCO2 and phytoplankton taxonomic composition.
    Keywords: Carbon dioxide, partial pressure; Chlorophyll a; CORSACS II; Depth, bottom/max; Depth, top/min; DEPTH, water; Dominant species of live fauna; Event label; Latitude of event; Longitude of event; Nathaniel B. Palmer; NBP0608; NBP0608_SW14; NBP0608_SW20; NBP0608_SW21; NBP0608_SW23; NBP0608_SW28; NBP0608_SW32; NBP0608_SW35; NBP0608_SW38; NBP0608_SW41; NBP0608_SW42; NBP0608_SW43; NBP0608_SW44; NBP0608_SW45; NBP0608_SW46; NBP0608_SW47; NBP0608_SW48; Nitrate; Priority Programme 1158 Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Ross Sea; Silicon dioxide; Southern Ocean; SPP1158; Surface water sample; SWS
    Type: Dataset
    Format: text/tab-separated-values, 108 data points
    Location Call Number Limitation Availability
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  • 4
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    PANGAEA
    In:  Supplement to: Rokitta, Sebastian D; Rost, Björn (2012): Effects of CO2 and their modulation by light in the life-cycle stages of the coccolithophore Emiliania huxleyi. Limnology and Oceanography, 57(2), 607-618, https://doi.org/10.4319/lo.2012.57.2.0607
    Publication Date: 2024-03-15
    Description: The effects of ocean acidification on the life-cycle stages of the coccolithophore Emiliania huxleyi and their by light were examined. Calcifying diploid and noncalcifying haploid cells (Roscoff culture collection 1216 and 1217) were acclimated to present-day and elevated CO2 partial pressures (PCO2; 38.5 vs. 101.3 Pa, ., 380 vs. 1000 matm) under low and high light (50 vs. 300 mmol photons m-2 s-1). Growth rates as well as quotas and production rates of C and N were measured. Sources of inorganic C for biomass buildup were using a 14C disequilibrium assay. Photosynthetic O2 evolution was measured as a function of dissolved inorganic C and light by means of membrane-inlet mass spectrometry. The diploid stage responded to elevated PCO2 by shunting resources from the production of particulate inorganic C toward organic C yet keeping the production of total particulate C constant. As the effect of ocean acidification was stronger under low light, the diploid stage might be less affected by increased acidity when energy availability is high. The haploid stage maintained elemental composition and production rates under elevated PCO2. Although both life-cycle stages involve different ways of dealing with elevated PCO2, the responses were generally modulated by energy availability, being typically most pronounced under low light. Additionally, PCO2 responses resembled those induced by high irradiances, indicating that ocean acidification affects the interplay between energy-generating processes (photosynthetic light reactions) and processes competing for energy (biomass buildup and calcification). A conceptual model is put forward explaining why the magnitude of single responses is determined by energy availability.
    Keywords: Alkalinity, Gran titration (Gran, 1950); Alkalinity, total; Alkalinity, total, standard deviation; Aragonite saturation state; Auto-analyzer, Technicon Traacs 800; Bicarbonate ion; Bicarbonate ion, standard deviation; Bicarbonate uptake/net fixation ratio; Bicarbonate uptake/net fixation ratio, standard deviation; Biomass/Abundance/Elemental composition; Bottles or small containers/Aquaria (〈20 L); Calcification/Dissolution; Calcite saturation state; Calcite saturation state, standard deviation; Calculated; Calculated, see reference(s); Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Carbon, inorganic, particulate, per cell; Carbon, organic, particulate, per cell; Carbon, organic, particulate/Nitrogen, organic, particulate ratio; Carbon, organic, particulate/Nitrogen, organic, particulate ratio, standard deviation; Carbonate ion; Carbonate ion, standard deviation; Carbonate system computation flag; Carbon dioxide; Carbon dioxide, partial pressure; Carbon dioxide, partial pressure, standard deviation; Chlorophyll a, standard deviation; Chlorophyll a/particulate organic carbon ratio; Chlorophyll a/particulate organic carbon ratio, standard deviation; Chlorophyll a per cell; Chromista; Emiliania huxleyi; EPOCA; Estimated; EUR-OCEANS; European network of excellence for Ocean Ecosystems Analysis; European Project on Ocean Acidification; Experimental treatment; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate; Growth rate, standard deviation; Haptophyta; Laboratory experiment; Laboratory strains; Light; Light:Dark cycle; Mass spectrometer SL 20-20 (SerCon); Nitrate; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Particulate inorganic carbon, production, standard deviation; Particulate inorganic carbon/particulate organic carbon ratio; Particulate inorganic carbon/particulate organic carbon ratio, standard deviation; Particulate inorganic carbon per cell, standard deviation; Particulate inorganic carbon production per cell; Particulate organic carbon, production, standard deviation; Particulate organic carbon content per cell, standard deviation; Particulate organic carbon production per cell; Particulate organic nitrogen per cell; Particulate organic nitrogen per cell, standard deviation; Particulate organic nitrogen production, standard deviation; Pelagos; pH; pH, standard deviation; pH meter, WTW, pH 3000; Phosphate; Phytoplankton; Pigments, Turner fluorometer; Primary production/Photosynthesis; Production of particulate organic nitrogen; Radiation, photosynthetically active; Salinity; Single species; Species; Temperature, water; Total particulate carbon production, standard deviation; Total particulate carbon production per cell
    Type: Dataset
    Format: text/tab-separated-values, 536 data points
    Location Call Number Limitation Availability
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  • 5
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    PANGAEA
    In:  Supplement to: Eichner, Meri; Kranz, Sven A; Rost, Björn (2014): Combined effects of different CO2 levels and N sources on the diazotrophic cyanobacterium Trichodesmium. Physiologia Plantarum, 152(2), 316-330, https://doi.org/10.1111/ppl.12172
    Publication Date: 2024-03-15
    Description: To predict effects of climate change and possible feedbacks, it is crucial to understand the mechanisms behind CO2 responses of biogeochemically relevant phytoplankton species. Previous experiments on the abundant N2 fixers Trichodesmium demonstrated strong CO2 responses, which were attributed to an energy reallocation between its carbon (C) and nitrogen (N) acquisition. Pursuing this hypothesis, we manipulated the cellular energy budget by growing Trichodesmium erythraeum IMS101 under different CO2 partial pressure (pCO2) levels (180, 380, 980 and 1400?µatm) and N sources (N2 and NO3-). Subsequently, biomass production and the main energy-generating processes (photosynthesis and respiration) and energy-consuming processes (N2 fixation and C acquisition) were measured. While oxygen fluxes and chlorophyll fluorescence indicated that energy generation and its diurnal cycle was neither affected by pCO2 nor N source, cells differed in production rates and composition. Elevated pCO2 increased N2 fixation and organic C and N contents. The degree of stimulation was higher for nitrogenase activity than for cell contents, indicating a pCO2 effect on the transfer efficiency from N2 to biomass. pCO2-dependent changes in the diurnal cycle of N2 fixation correlated well with C affinities, confirming the interactions between N and C acquisition. Regarding effects of the N source, production rates were enhanced in NO3-grown cells, which we attribute to the higher N retention and lower ATP demand compared with N2 fixation. pCO2 effects on C affinity were less pronounced in NO3- users than N2 fixers. Our study illustrates the necessity to understand energy budgets and fluxes under different environmental conditions for explaining indirect effects of rising pCO2.
    Keywords: Alkalinity, total; Alkalinity, total, standard deviation; Aragonite saturation state; Bacteria; Bicarbonate ion; Bottles or small containers/Aquaria (〈20 L); Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, half saturation concentration; Carbon, inorganic, dissolved, half saturation concentration, standard deviation; Carbon, inorganic, dissolved, standard deviation; Carbon, organic, particulate, standard deviation; Carbon, organic, particulate/Nitrogen, organic, particulate ratio; Carbon, organic, particulate/Nitrogen, organic, particulate ratio, standard deviation; Carbon, organic, particulate per chlorophyll a; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Coulometric titration; Cyanobacteria; Effective absorbance cross-section of photosystem II; Effective absorbance cross-section of photosystem II, standard deviation; Figure; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate; Growth rate, standard deviation; Identification; Irradiance; Laboratory experiment; Laboratory strains; Light:Dark cycle; Macro-nutrients; Maximum photochemical quantum yield of photosystem II; Maximum photochemical quantum yield of photosystem II, standard deviation; Net oxygen evolution, per chlorophyll a; Net oxygen evolution, per chlorophyll a, standard deviation; Nitrogen, organic, particulate, standard deviation; Nitrogen, organic, particulate per chlorophyll a; Nitrogen fixation rate per chlorophyll a; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Other metabolic rates; Partial pressure of carbon dioxide, standard deviation; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Particulate organic carbon, production, standard deviation; Particulate organic carbon production, per chlorophyll a; Particulate organic nitrogen production, per chlorophyll a; Particulate organic nitrogen production, standard deviation; Pelagos; pH; pH, standard deviation; Phytoplankton; Potentiometric; Potentiometric titration; Primary production/Photosynthesis; Re-oxidation time of the Qa acceptor; Re-oxidation time of the Qa acceptor, standard deviation; Respiration; Salinity; Single species; Species; Temperature, water; Time in hours; Time point, descriptive; Treatment; Trichodesmium erythraeum
    Type: Dataset
    Format: text/tab-separated-values, 1523 data points
    Location Call Number Limitation Availability
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  • 6
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    PANGAEA
    In:  Supplement to: Rokitta, Sebastian D; John, Uwe; Rost, Björn (2012): Ocean Acidification Affects Redox-Balance and Ion-Homeostasis in the Life-Cycle Stages of Emiliania huxleyi. PLoS ONE, 7(12), e52212, https://doi.org/10.1371/journal.pone.0052212
    Publication Date: 2024-03-15
    Description: Ocean Acidification (OA) has been shown to affect photosynthesis and calcification in the coccolithophore Emiliania huxleyi, a cosmopolitan calcifier that significantly contributes to the regulation of the biological carbon pumps. Its non-calcifying, haploid life-cycle stage was found to be relatively unaffected by OA with respect to biomass production. Deeper insights into physiological key processes and their dependence on environmental factors are lacking, but are required to understand and possibly estimate the dynamics of carbon cycling in present and future oceans. Therefore, calcifying diploid and non-calcifying haploid cells were acclimated to present and future CO2 partial pressures (pCO2; 38.5 Pa vs. 101.3 Pa CO2) under low and high light (50 vs. 300 µmol photons/m**2 /s). Comparative microarray-based transcriptome profiling was used to screen for the underlying cellular processes and allowed to follow up interpretations derived from physiological data. In the diplont, the observed increases in biomass production under OA are likely caused by stimulated production of glycoconjugates and lipids. The observed lowered calcification under OA can be attributed to impaired signal-transduction and ion-transport. The haplont utilizes distinct genes and metabolic pathways, reflecting the stage-specific usage of certain portions of the genome. With respect to functionality and energy-dependence, however, the transcriptomic OA-responses resemble those of the diplont. In both life-cycle stages, OA affects the cellular redox-state as a master regulator and thereby causes a metabolic shift from oxidative towards reductive pathways, which involves a reconstellation of carbon flux networks within and across compartments. Whereas signal transduction and ion-homeostasis appear equally OA-sensitive under both light intensities, the effects on carbon metabolism and light physiology are clearly modulated by light availability. These interactive effects can be attributed to the influence of OA and light on the redox equilibria of NAD and NADP, which function as major sensors for energization and stress. This generic mode of action of OA may therefore provoke similar cell-physiological responses in other protists.
    Keywords: Alkalinity, total; Alkalinity, total, standard deviation; Aragonite saturation state; Bicarbonate ion; Bicarbonate ion, standard deviation; Bottles or small containers/Aquaria (〈20 L); Calcite saturation state; Calcite saturation state, standard deviation; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Carbonate ion; Carbonate ion, standard deviation; Carbonate system computation flag; Carbon dioxide; Category; Chromista; Emiliania huxleyi; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Gene abundance; Gene expression (incl. proteomics); Group; Haptophyta; Irradiance; Laboratory experiment; Laboratory strains; Light; North Atlantic; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide, standard deviation; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; pH; pH, standard deviation; Phytoplankton; Potentiometric; Potentiometric titration; Salinity; Single species; Species; Strain; Temperature, water
    Type: Dataset
    Format: text/tab-separated-values, 696 data points
    Location Call Number Limitation Availability
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  • 7
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    PANGAEA
    In:  Supplement to: Eichner, Meri; Rost, Björn; Kranz, Sven A (2014): Diversity of ocean acidification effects on marine N2 fixers. Journal of Experimental Marine Biology and Ecology, 457, 199-207, https://doi.org/10.1016/j.jembe.2014.04.015
    Publication Date: 2024-03-15
    Description: Considering the important role of N2 fixation for primary productivity and CO2 sequestration, it is crucial to assess the response of diazotrophs to ocean acidification. Previous studies on the genus Trichodesmium suggested a strong sensitivity towards ocean acidification. In view of the large functional diversity in N2 fixers, the objective of this study was to improve our knowledge of the CO2 responses of other diazotrophs. To this end, the single-celled Cyanothece sp. and two heterocystous species, Nodularia spumigena and the symbiotic Calothrix rhizosoleniae, were acclimated to two pCO2 levels (380 vs. 980 µatm). Growth rates, cellular composition (carbon, nitrogen and chlorophyll a) as well as carbon and N2 fixation rates (14C incorporation, acetylene reduction) were measured and compared to literature data on different N2 fixers. The three species investigated in this study responded differently to elevated pCO2, showing enhanced, decreased as well as unaltered growth and production rates. For instance, Cyanothece increased production rates with pCO2, which is in line with the general view that N2 fixers benefit from ocean acidification. Due to lowered growth and production of Nodularia, nitrogen input to the Baltic Sea might decrease in the future. In Calothrix, no significant changes in growth or production could be observed, even though N2 fixation was stimulated under elevated pCO2. Reviewing literature data confirmed a large variability in CO2 sensitivity across diazotrophs. The contrasting response patterns in our and previous studies were discussed with regard to the carbonate chemistry in the respective natural habitats, the mode of N2 fixation as well as differences in cellular energy limitation between the species. The group-specific CO2 sensitivities will impact differently on future biogeochemical cycles of open-ocean environments and systems like the Baltic Sea and should therefore be considered in models estimating climate feedback effects.
    Keywords: Alkalinity, total; Alkalinity, total, standard deviation; Aragonite saturation state; Bacteria; Bicarbonate ion; Bottles or small containers/Aquaria (〈20 L); Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Calothrix rhizosoleniae; Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Carbon, organic, particulate/Nitrogen, organic, particulate ratio; Carbon, organic, particulate/Nitrogen, organic, particulate ratio, standard deviation; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Carbon fixation rate, per chlorophyll a; Carbon fixation rate, per chlorophyll a, standard deviation; Chlorophyll a, standard deviation; Chlorophyll a per cell; Coulometric titration; Cyanobacteria; Cyanothece sp.; Ethene production, per chlorophyll a; Ethene production per cell; Ethene production standard deviation; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate; Growth rate, standard deviation; Irradiance; Laboratory experiment; Laboratory strains; Nodularia spumigena; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Other metabolic rates; Partial pressure of carbon dioxide, standard deviation; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Particulate organic carbon, per cell; Particulate organic carbon, production, standard deviation; Particulate organic carbon content per cell, standard deviation; Particulate organic carbon production, per chlorophyll a; Particulate organic nitrogen per cell; Particulate organic nitrogen per cell, standard deviation; Particulate organic nitrogen production, per chlorophyll a; Particulate organic nitrogen production, standard deviation; Pelagos; pH; pH, standard deviation; Phytoplankton; Potentiometric; Potentiometric titration; Primary production/Photosynthesis; Salinity; Single species; Species; Temperature, water; Treatment
    Type: Dataset
    Format: text/tab-separated-values, 241 data points
    Location Call Number Limitation Availability
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  • 8
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    PANGAEA
    In:  Supplement to: Kranz, Sven A; Levitan, Orly; Richter, Klaus-Uwe; Prasil, O; Beran-Frank, Ilana; Rost, Björn (2010): Combined effects of CO2 and light on the N2-fixing cyanobacterium Trichodesmium IMS101: Physiological responses. Plant Physiology, 154, 334-345, https://doi.org/10.1104/pp.110.159145
    Publication Date: 2024-03-15
    Description: Recent studies on the diazotrophic cyanobacterium Trichodesmium erythraeum(IMS101) showed that increasing CO2 partial pressure (pCO2) enhances N2 fixation and growth. Significant uncertainties remain as to the degree of the sensitivity to pCO2, its modification by other environmental factors, and underlying processes causing these responses. To address these questions, we examined the responses ofTrichodesmium IMS101 grown under a matrix of low and high levels of pCO2 (150 and 900 µatm) and irradiance (50 and 200 µmol photons m-2 s-1). Growth rates as well as cellular carbon and nitrogen contents increased with increasing pCO2 and light levels in the cultures. The pCO2-dependent stimulation in organic carbon and nitrogen production was highest under low light. High pCO2 stimulated rates of N2fixation and prolonged the duration, while high light affected maximum rates only. Gross photosynthesis increased with light but did not change with pCO2. HCO3- was identified as the predominant carbon source taken up in all treatments. Inorganic carbon uptake increased with light, but only gross CO2 uptake was enhanced under high pCO2. A comparison between carbon fluxes in vivo and those derived from 13C fractionation indicates high internal carbon cycling, especially in the low-pCO2treatment under high light. Light-dependent oxygen uptake was only detected underlow pCO2 combined with high light or when low-light-acclimated cells were exposed to high light, indicating that the Mehler reaction functions also as a photoprotective mechanism in Trichodesmium. Our data confirm the pronounced pCO2 effect on N2fixation and growth in Trichodesmium and further show a strong modulation of these effects by light intensity. We attribute these responses to changes in the allocation of photosynthetic energy between carbon acquisition and the assimilation of carbon and nitrogen under elevated pCO2. These findings are supported by a complementarystudy looking at photosynthetic fluorescence parameters of photosystem II, photosynthetic unit stoichiometry (photosystem I:photosystem II), and pool sizes of key proteins in carbon and nitrogen acquisition.
    Keywords: Alkalinity, Gran titration (Gran, 1950); Alkalinity, total; Alkalinity, total, standard deviation; Aragonite saturation state; Bacteria; Bicarbonate ion; Bicarbonate uptake in chlorophyll, standard deviation; Bicarbonate uptake rate, per chlorophyll a; Biomass/Abundance/Elemental composition; Bottles or small containers/Aquaria (〈20 L); Calcite saturation state; Calculated; Calculated, see reference(s); Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Carbon, organic, particulate, per cell; Carbon/Nitrogen ratio; Carbon/Nitrogen ratio, standard deviation; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Carbon dioxide, standard deviation; Carbon dioxide uptake, per chlorophyll, standard deviation; Carbon dioxide uptake rate, per chlorophyll a; Chlorophyll a, standard deviation; Chlorophyll a per cell; Comment; Cyanobacteria; Determined by acetylene reduction assay using a gas chromatograph; EPOCA; EUR-OCEANS; European network of excellence for Ocean Ecosystems Analysis; European Project on Ocean Acidification; Experimental treatment; Fixation of carbon in chlorophyll; Fixation of carbon in chlorophyll, standard deviation; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Gross oxygen evolution, per chlorophyll a; Gross oxygen evolution, standard deviation; Growth/Morphology; Growth rate; Growth rate, standard deviation; Laboratory experiment; Laboratory strains; Light; Mass spectrometer ANCA-SL 20-20 Europa Scientific; Nitrogen fixation rate, standard deviation; Nitrogen fixation rate per chlorophyll a; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Other metabolic rates; Oxygen consumption, standard deviation; Oxygen consumption per chlorophyll a; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Particulate organic carbon, production, standard deviation; Particulate organic carbon content per cell, standard deviation; Particulate organic carbon production per cell; Particulate organic nitrogen per cell; Particulate organic nitrogen per cell, standard deviation; Particulate organic nitrogen production, standard deviation; Particulate organic phosphorus per cell; Particulate organic phosphorus per cell, standard deviation; Pelagos; pH; pH, standard deviation; pH meter (Metrohm electrodes); Phytoplankton; Primary production/Photosynthesis; Production of particulate organic nitrogen; Radiation, photosynthetically active; Respiration; Salinity; see reference(s); Single species; Temperature, water; Time in hours; Trichodesmium sp.
    Type: Dataset
    Format: text/tab-separated-values, 1788 data points
    Location Call Number Limitation Availability
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  • 9
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    PANGAEA
    In:  Supplement to: Levitan, Orly; Kranz, Sven A; Spungin, D; Prasil, O; Rost, Björn; Beran-Frank, Ilana (2010): Combined effects of CO2 and light on the N2-fixing cyanobacterium Trichodesmium IMS101: A mechanistic view. Plant Physiology, 154, 346-356, https://doi.org/10.1104/pp.110.159285
    Publication Date: 2024-03-15
    Description: The marine diazotrophic cyanobacterium Trichodesmium responds to elevated atmospheric CO2 partial pressure (pCO2) with higher N2 fixation and growth rates. To unveil the underlying mechanisms, we examined the combined influence of pCO2(150 and 900 µatm) and light (50 and 200 µmol photons m-2 s-1) on TrichodesmiumIMS101. We expand on a complementary study that demonstrated that while elevated pCO2 enhanced N2 fixation and growth, oxygen evolution and carbon fixation increased mainly as a response to high light. Here, we investigated changes in the photosynthetic fluorescence parameters of photosystem II, in ratios of the photosynthetic units (photosystem I:photosystem II), and in the pool sizes of key proteins involved in the fixation of carbon and nitrogen as well as their subsequent assimilation. We show that the combined elevation in pCO2 and light controlled the operation of the CO2-concentrating mechanism and enhanced protein activity without increasing their pool size. Moreover, elevated pCO2 and high light decreased the amounts of several key proteins (NifH, PsbA, and PsaC), while amounts of AtpB and RbcL did not significantly change. Reduced investment in protein biosynthesis, without notably changing photosynthetic fluxes, could free up energy that can be reallocated to increase N2 fixation and growth at elevated pCO2 and light. We suggest that changes in the redox state of the photosynthetic electron transportchain and posttranslational regulation of key proteins mediate the high flexibility in resources and energy allocation in Trichodesmium. This strategy should enableTrichodesmium to flourish in future surface oceans characterized by elevated pCO2, higher temperatures, and high light.
    Keywords: Alkalinity, Gran titration (Gran, 1950); Alkalinity, total; Aragonite saturation state; Bacteria; Bicarbonate ion; Bottles or small containers/Aquaria (〈20 L); Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; CF1 subunit of ATP synthase protein; CF1 subunit of ATP synthase protein, standard deviation; Comment; Cyanobacteria; Effective absorbance cross-section of photosystem II; Effective absorbance cross-section of photosystem II, standard deviation; Electron transport rate of photosystem II, per cell; Electron transport rate of photosystem II, standard deviation; EPOCA; EUR-OCEANS; European network of excellence for Ocean Ecosystems Analysis; European Project on Ocean Acidification; Experimental treatment; Fluorescence, intrinsic; Fluorescence, intrinsic, standard deviation; Fluorescence, maximum; Fluorescence, maximum, standard deviation; Fluorescence, variable; Fluorescence, variable, standard deviation; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); GlnA subunit of Gln synthetase; GlnA subunit of Gln synthetase, standard deviation; Iron protein of nitrogenase; Iron protein of nitrogenase, standard deviation; Laboratory experiment; Laboratory strains; Light; Maximum photochemical quantum yield of photosystem II; Maximum photochemical quantum yield of photosystem II, standard deviation; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Open photosystem II reaction centers; Open photosystem II reaction centers, standard deviation; Other metabolic rates; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; pH; Photosynthetic protein, PsbA, standard deviation; Photosynthetic protein, PsbC; Photosynthetic protein, PsbC, standard deviation; Photosynthetic protein PsbA; Photosynthetic protein Rubisco; Photosynthetic protein Rubisco, standard deviation; Phytoplankton; Primary production/Photosynthesis; Radiation, photosynthetically active; Salinity; see reference(s); Single species; Temperature, water; Time in hours; Trichodesmium sp.
    Type: Dataset
    Format: text/tab-separated-values, 608 data points
    Location Call Number Limitation Availability
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  • 10
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    PANGAEA
    In:  Supplement to: Beaufort, Luc; Probert, Ian; de Garidel-Thoron, Thibault; Bendif, E M; Ruiz-Pino, Diana; Metzi, N; Goyet, Catherine; Buchet, Noëlle; Coupel, Pierre; Grelaud, Michaël; Rost, Björn; Rickaby, Rosalind E M; De Vargas, Colomban (2011): Sensitivity of coccolithophores to carbonate chemistry and ocean acidification. Nature, 476, 80-83, https://doi.org/10.1038/nature10295
    Publication Date: 2024-03-15
    Description: About one-third of the carbon dioxide (CO2) released into the atmosphere as a result of human activity has been absorbed by the oceans, where it partitions into the constituent ions of carbonic acid. This leads to ocean acidification, one of the major threats to marine ecosystems and particularly to calcifying organisms such as corals, foraminifera and coccolithophores. Coccolithophores are abundant phytoplankton that are responsible for a large part of modern oceanic carbonate production. Culture experiments investigating the physiological response of coccolithophore calcification to increased CO2 have yielded contradictory results between and even within species. Here we quantified the calcite mass of dominant coccolithophores in the present ocean and over the past forty thousand years, and found a marked pattern of decreasing calcification with increasing partial pressure of CO2 and concomitant decreasing concentrations of CO3. Our analyses revealed that differentially calcified species and morphotypes are distributed in the ocean according to carbonate chemistry. A substantial impact on the marine carbon cycle might be expected upon extrapolation of this correlation to predicted ocean acidification in the future. However, our discovery of a heavily calcified Emiliania huxleyi morphotype in modern waters with low pH highlights the complexity of assemblage-level responses to environmental forcing factors.
    Keywords: Age, dated; Alkalinity, total; Antarctic; Aragonite saturation state; Bicarbonate ion; Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; CTD, Sea-Bird SBE 911plus; Emiliania huxleyi; Emiliania huxleyi, diameter; Emiliania huxleyi, weight; Emiliania huxleyi, weight, standard error; EPOCA; Estimated by measuring brightness in cross-polarized light (birefringence); EUR-OCEANS; European network of excellence for Ocean Ecosystems Analysis; European Project on Ocean Acidification; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Indian Ocean; LATITUDE; LONGITUDE; Measured and/or detected by SYRACO software; North Atlantic; North Pacific; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); pH; Phytoplankton; Replicates; Salinity; Sample ID; South Atlantic; South Pacific; Temperature, water; Titration potentiometric
    Type: Dataset
    Format: text/tab-separated-values, 16400 data points
    Location Call Number Limitation Availability
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