A5077894442- Marine and coastal ecosystems
- Ocean Acidification Effects and Responses
- Marine Biology and Ecology Research
- Microbial Community Ecology and Physiology
- Marine Bivalve and Aquaculture Studies
- Algal biology and biofuel production
- Methane Hydrates and Related Phenomena
- Protist diversity and phylogeny
- Calcium Carbonate Crystallization and Inhibition
- Isotope Analysis in Ecology
- Coral and Marine Ecosystems Studies
- Diatoms and Algae Research
- Aquatic Ecosystems and Phytoplankton Dynamics
- Paleontology and Stratigraphy of Fossils
- Atmospheric and Environmental Gas Dynamics
- Physiological and biochemical adaptations
- Mass Spectrometry Techniques and Applications
- Marine and coastal plant biology
- Genomics and Phylogenetic Studies
- Marine Toxins and Detection Methods
- Arctic and Antarctic ice dynamics
- Machine Learning in Bioinformatics
- Photosynthetic Processes and Mechanisms
- Water Quality Monitoring and Analysis
- Cancer Research and Treatments
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung
2016-2025
University of Bremen
2019-2024
Biogéosciences
2013
Czech Academy of Sciences
2010
Czech Academy of Sciences, Institute of Microbiology
2010
Bar-Ilan University
2010
Friedrich Schiller University Jena
1938-1939
Carbon acquisition in relation to CO 2 supply was investigated three marine bloom‐forming microalgae, the diatom Skeletonema costatum , flagellate Phaeocystis globosa and coccolithophorid Emiliania huxleyi . In vivo activities of extracellular (eCA) intracellular (iCA) carbonic anhydrase activity, photosynthetic O evolution, HCO 3 − uptake rates were measured by membrane inlet mass spectrometry cells acclimated pCO levels 36, 180, 360, 1,800 ppmv. Large differences obtained between species...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 373:227-237 (2008) - DOI: https://doi.org/10.3354/meps07776 Contribution Theme Section ‘Effects of ocean acidification on marine ecosystems’ Sensitivity phytoplankton future changes in carbonate chemistry: current knowledge, contradictions and research directions Björn Rost*, Ingrid Zondervan, Dieter...
The Southern Ocean exerts a strong impact on marine biogeochemical cycles and global air‐sea CO 2 fluxes. Over the coming century, large increases in surface ocean levels, combined with increased upper water column temperatures stratification, are expected to diminish uptake. These effects could be significantly modulated by concomitant ‐dependent changes region's biological carbon pump. Here we show that concentrations affect physiology, growth species composition of phytoplankton...
Abstract Marine phytoplankton have many obvious characters, such as rapid cell division rates and large population sizes, that give them the capacity to evolve in response global change on timescales of weeks, months or decades. However, few studies directly investigate if this adaptive potential is likely be realized. Because this, evidence whether how marine may sparse. Here, we review help predict evolutionary responses phytoplankton. We find limited support from experimental evolution...
Abstract The Arctic experiences climate changes that are among the fastest in world and affect all Earth system components. Despite expected increase terrigenous inputs to Ocean, their impacts on biogeochemical cycles currently largely neglected IPCC-like models. Here we used a state-of-the-art high-resolution ocean biogeochemistry model includes carbon nutrient from rivers coastal erosion produce twenty-first-century pan-Arctic projections. Surprisingly, even with an anticipated rise...
In laboratory experiments with the coccolithophore species Emiliania huxleyi and Gephyrocapsa oceanica , ratio of particulate inorganic carbon (PIC) to organic (POC) production decreased increasing CO 2 concentration ([CO ]). This was due both reduced PIC enhanced POC at elevated [CO ]. Carbon dioxide concentrations covered a range from preindustrial level value predicted for 2100 according “business as usual” anthropogenic emission scenario. The results were used employ model in which...
The effects of ocean acidification on the life‐cycle stages coccolithophore Emiliania huxleyi and their modulation by light were examined. Calcifying diploid noncalcifying haploid cells (Roscoff culture collection strains 1216 1217) acclimated to present‐day elevated CO 2 partial pressures (P ; 38.5 vs. 101.3 Pa, i.e., 380 1000 µatm) under low high (50 300 µmol photons m −2 s −1 ). Growth rates as well cellular quotas production C N measured. Sources inorganic for biomass buildup determined...
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 degree of sensitivity pCO2, its modification by other environmental factors, underlying processes causing these responses. To address questions, we examined responses IMS101 grown under a matrix low high levels pCO2 (150 900 μatm) irradiance (50 200 μmol photons m−2 s−1). Growth rates...
We investigated carbon acquisition by the N 2 ‐fixing cyanobacterium Trichodesmium IMS101 in response to CO levels of 15.1, 37.5, and 101.3 Pa (equivalent 150, 370, 1000 ppm). In these acclimations, growth rates as well cellular C contents were measured. vivo activities carbonic anhydrase (CA), photosynthetic O evolution, HCO 3 ‐ fluxes measured using membrane inlet mass spectrometry 14 disequilibrium technique. While no differences observed, elevated caused higher quotas stimulated...
The potential interactive effects of iron (Fe) limitation and Ocean Acidification in the Southern (SO) are largely unknown. Here we present results a long-term incubation experiment investigating combined CO2 Fe availability on natural phytoplankton assemblages from Weddell Sea, Antarctica. Active Chl fluorescence measurements revealed that successfully cultured under both Fe-depleted Fe-enriched conditions. treatments had significant photosynthetic efficiency (Fv/Fm; 0.3 for 0.5...
Despite the fact that ocean acidification is considered to be especially pronounced in Southern Ocean, little known about CO 2 ‐dependent physiological processes and interactions of Antarctic phytoplankton key species. We therefore studied effects partial pressure (P CO2 ) (16.2, 39.5, 101.3 Pa) on growth photosynthetic carbon acquisition bloom‐forming species Chaetoceros debilis, Pseudo‐nitzschia subcurvata, Fragilariopsis kerguelensis, Phaeocystis antarctica. Using membrane‐inlet mass...
Summary There is increasing evidence that different light intensities strongly modulate the effects of ocean acidification ( OA ) on marine phytoplankton. The aim present study was to investigate interactive and dynamic light, mimicking natural mixing regimes. Antarctic diatom C haetoceros debilis grown under two p CO 2 (390 1000 μatm) conditions (constant dynamic), latter yielding same integrated irradiance over day. To characterize between treatments, growth, elemental composition, primary...
Marine heatwaves are increasing in frequency and intensity as climate change progresses, especially the highly productive Arctic regions. Although their effects on primary producers will largely determine impacts ecosystem services, mechanistic understanding phytoplankton responses to these extreme events is still very limited. We experimentally exposed assemblages stable warming, well repeated heatwaves, measured temporally resolved productivity, physiology, composition. Our results show...
The effects of pH-induced changes in seawater carbonate chemistry on inorganic carbon (C(i)) acquisition and domoic acid (DA) production were studied two potentially toxic diatom species, Pseudo-nitzschia multiseries Nitzschia navis-varingica, the non-toxic Stellarima stellaris. In vivo activities carbonic anhydrase (CA), photosynthetic O(2) evolution CO(2) HCO(3)(-) uptake rates measured by membrane inlet MS cells acclimated to low (7.9) high pH (8.4 or 8.9). Species-specific differences...
Carbon acquisition was investigated in three marine bloom-forming dinollagellates-Prorocentrum minimum, Heterocapsa triquetra and Ceratium lineatum. In vivo activities of extracellular intracellular carbonic anhydrase (CA), photosynthetic O2 evolution, CO2 HCO3- uptake rates were measured by membrane inlet mass spectrometry (MIMS) cells acclimated to low pH (8.0) high (8.5 or 9.1). A second approach used short-term 14C-disequilibrium incubations estimate the carbon source utilized cells. All...
The carbon isotopic composition of marine phytoplankton varies significantly with growth conditions. Aqueous CO 2 concentration [CO ] and algal rate (µ) have been suggested to be important factors determining isotope fractionation (ε p ). Here we examine ε the coccolithophorid Emiliania huxleyi in relation light conditions dilute batch cultures. Cells were incubated at different irradiance cycles, photon flux densities (PFDs), ]. Isotope varied between 6.7 12.3‰ under 16 : 8 h dark cycle (L...