Jorijntje Henderiks
Uppsala University, Department of Earth Sciences, Faculty Member
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Research Interests: Earth Sciences, Geology, Coral Reefs, Evolution, Carbon Cycle, and 12 moreBiological Sciences, Environmental Sciences, Ocean acidification, Fossil Fuels, Cenozoic, Biogeosciences, Natural Sciences, Ice Cores, Carbon Fibers, Atmospheric Carbon Dioxide, Ocean Chemistry, and Temperature Sensitive Polymer
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Major questions surround the species-specific nature of coccolithophore calcification in response to rising atmospheric carbon dioxide levels and the likely feedback of planktonic calcifiers. Recent evidence from rapidly accumulating... more
Major questions surround the species-specific nature of coccolithophore calcification in response to rising atmospheric carbon dioxide levels and the likely feedback of planktonic calcifiers. Recent evidence from rapidly accumulating sediments implies that some of the larger species of coccolithophore are increasing their calcification in response to anthropogenic change, which appears at odds with the paradigm view that coccolithophores reduce the
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Research Interests: Chemistry, Inorganic Chemistry, Organic Chemistry, Photosynthesis, Phytoplankton, and 13 moreCell and Molecular Biology, Experiment, Carbonate Chemistry, Stable Isotope, Carbonate, Natural Sciences, Emiliania Huxleyi, Marine Algae, Spectrum, Carbon Isotope, Growth rates, Dissolved Organic Carbon, and Calcification
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Is phosphate availability significant to the morphological diversity within Helicosphaera carteri?
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Strain-specific ecophysiological traits define the response to phosphorus limitation in Helicosphaera carteri
Research Interests: Biology and Phosphorus
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Temperature, but not phosphorus limitation, changes the ratio of calcite to organic carbon in Coccolithus pelagicus
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Phosphorus limitation does not change the ratio of calcite to organic carbon in Coccolithus pelagicus (Wallich)
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The study of calcareous marine biota provides important insight into the climate past, present and future. Biocalcification by marine biota has evolved across many major phyla (e.g. bacteria, eukar ...
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ABSTRACT There is much debate about the response of coccolithophores to decreased carbonate saturation state and decreased pH in the ocean as a result of increased CO2 partial pressure. It is still not known whether coccolithophores act... more
ABSTRACT There is much debate about the response of coccolithophores to decreased carbonate saturation state and decreased pH in the ocean as a result of increased CO2 partial pressure. It is still not known whether coccolithophores act as a sink or source for CO CO2. Nor is it known whether calcification will be reduced or increased in response to climate change. A proper understanding of the relationship between calcification and climate change is important not only because coccolithophores play an important role in determining the PIC:POC ratio of particle export into the deep ocean but also because climate change may affect the overall biodiversity of phytoplankton and the marine food chain. Because ocean acidification strongly affects polar regions, initially it seems unlikely that coccolithophores should prefer polar waters or even be a major component of phytoplankton in these regions. Yet there is much recent evidence that coccolithophores are increasingly expanding their range into polar oceans. This observation could be pivotal in improving our understanding of the mechanisms and rates of climatic adaptation by natural coccolithophore populations. We postulate that coccolithophores may be more sensitive to recent environmental changes, such as SSTs and salinity, than to factors more directly linked to changing ocean carbonate chemistry
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Marine phytoplankton, such as diatoms and coccolithophores, constitute the base of the marine food chain and are a fundamental component in biogeochemical cycles. The overall ecological success of marine phytoplankton, but also its... more
Marine phytoplankton, such as diatoms and coccolithophores, constitute the base of the marine food chain and are a fundamental component in biogeochemical cycles. The overall ecological success of marine phytoplankton, but also its taxonomic diversity and size distribution, ...
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Marine phytoplankton, such as diatoms and coccolithophores, constitute the base of the marine food chain and are a fundamental component in biogeochemical cycles. The overall ecological success of ...
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Excess anthropogenic atmospheric CO2 is absorbed largely by the oceans, causing acidification of the biologically productive surface waters with potential detrimental effects on marine biocalcifica ...
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The coccolithophore species Emiliania huxleyi is characterized by a wide range of sizes, which can be easily distinguished in the light microscope. In this study we have quantified the abundance of large (coccoliths > 4 µm in maximum... more
The coccolithophore species Emiliania huxleyi is characterized by a wide range of sizes, which can be easily distinguished in the light microscope. In this study we have quantified the abundance of large (coccoliths > 4 µm in maximum length) E. huxleyi specimens during the last 25 kyr in sedimentary records from eleven cores and drill sites in the NE Atlantic and W Mediterranean Sea, to prove its usefulness in the reconstruction of water mass dynamics and biostratigraphic potential.During the Last Glacial Maximum this large form, a cold-water indicator, was common in the NE Atlantic and Mediterranean, and its regional variation in abundance indicates a displacement of the climatic zones southwards in agreement with the development of ice sheets and sea ice in the Northern Hemisphere during this period. On the other hand, the gradient between northern and southern surface water masses in the Subtropical Gyre appears to have been more pronounced than at present, while the Portugal and Canary Currents were more intense. In the western Mediterranean basin temperatures were cooler than in the adjacent Atlantic, provoking a quasi-endemism of these specimens until the end of Heinrich Event 1. This may have been due to a restriction in the communication between the Atlantic and Mediterranean through the Strait of Gibraltar, the arrival of cold surface water and the amplification of cooling after the development of ice sheets in the Northern Hemisphere.During the deglaciation, large E. huxleyi specimens decreased in abundance at medium and low latitudes, but were still numerous close to the Subarctic region during the Holocene. In transitional waters this decrease to present day abundances occurred after Termination Ib.The abrupt change in abundance of this large E. huxleyi form is proposed as a new biostratigraphic event to characterize the Holocene in mid- to low-latitude water masses in the North Atlantic, although this horizon seems to be diachronous by 5 kyr from tropical to subarctic regions, in agreement with th [...]
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The ecological preferences of different Phytoplankton types drive their temporal and spatial distributions, reflecting their dependence on certain temperature ranges, light levels, nutrient availability and other environmental gradients.... more
The ecological preferences of different Phytoplankton types drive their temporal and spatial distributions, reflecting their dependence on certain temperature ranges, light levels, nutrient availability and other environmental gradients. Hence, some phytoplankton taxa can be used as water mass tracers (biotracers).
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Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity,... more
Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity, gamma radiation, velocity, density, borehole images,…) in any hole depends on the scientific objectives and operational constraints.
Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity,... more
Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity, gamma radiation, velocity, density, borehole images,…) in any hole depends on the scientific objectives and operational constraints.
Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity,... more
Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity, gamma radiation, velocity, density, borehole images,…) in any hole depends on the scientific objectives and operational constraints.
The biogeochemical impact of coccolithophores is defined by their overall abundance in the oceans, but also by a wide range in physiological traits such as cell size, degree of calcification and carbon production rates between different... more
The biogeochemical impact of coccolithophores is defined by their overall abundance in the oceans, but also by a wide range in physiological traits such as cell size, degree of calcification and carbon production rates between different species. Species' "sensitivity" to environmental forcing has been suggested to relate to their cellular PIC:POC ratio and other physiological constraints. Understanding both the short and longer-term adaptive strategies of different coccolithophore lineages, and how these in turn shape the biogeochemical role of the group, is therefore crucial for modeling the ongoing changes in the global carbon cycle. Here we present data on the phenotypic evolution of a large and heavily-calcified genus Helicosphaera (order Zygodiscales) over the past 15 million years (Ma), at two deep-sea drill sites from the tropical Indian Ocean and temperate South Atlantic. The modern species Helicosphaera carteri, which displays eco-physiological adaptations in ...
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Phosphorus limitation does not change the ratio of calcite to organic carbon in Coccolithus pelagicus (Wallich)
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All species of coccolithophore appear to respond to perturbations of carbonate chemistry in a different way. Here, we show that the degree of malformation, growth rate and stable isotopic composition of organic matter and carbonate... more
All species of coccolithophore appear to respond to perturbations of carbonate chemistry in a different way. Here, we show that the degree of malformation, growth rate and stable isotopic composition of organic matter and carbonate produced by two contrasting species of coccolithophore (Gephyrocapsa oceanica and Coccolithus pelagicus ssp. braarudii) are indicative of differences between their photosynthetic and calcification response to changing DIC levels (ranging from ~1100 to ~7800 µmol/kg) at constant pH (8.13 ± 0.02). Gephyrocapsa oceanica thrived under all conditions of DIC, showing evidence of increased growth rates at higher DIC, but C. braarudii was detrimentally affected at high DIC showing signs of malformation, and decreased growth rates. The carbon isotopic fractionation into organic matter and the coccoliths suggests that C. braarudii utilises a common internal pool of carbon for calcification and photosynthesis but G. oceanica relies on independent supplies for each process. All coccolithophores appear to utilize bicarbonate as their ultimate source of carbon for calcification resulting in the release of a proton. But, we suggest that this proton can be harnessed to enhance the supply of CO2(aq) for photosynthesis either from a large internal HCO3- pool which acts as a pH buffer (C. braarudii), or pumped externally to aid the diffusive supply of CO2 across the membrane from the abundant HCO3- (G. oceanica), likely mediated by an internal and external carbonic anhydrase respectively. Our simplified hypothetical spectrum of physiologies may provide a context to understand different species response to changing pH and DIC, the species-specific delta p and calcite "vital effects", as well as accounting for geological trends in coccolithophore cell size.
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Is phosphate availability significant to the morphological diversity within Helicosphaera carteri?
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Marine phytoplankton, such as diatoms and coccolithophores, constitute the base of the marine food chain and are a fundamental component in biogeochemical cycles. The overall ecological success of marine phytoplankton, but also its... more
Marine phytoplankton, such as diatoms and coccolithophores, constitute the base of the marine food chain and are a fundamental component in biogeochemical cycles. The overall ecological success of marine phytoplankton, but also its taxonomic diversity and size distribution, determines the efficiency by which fixed carbon is transferred to higher trophic levels and into the deep ocean- and sedimentary carbon reservoirs. In recent years, several hypotheses have been invoked to explain distinct macroevolutionary decreases in the cell size of phytoplankton during the Cenozoic. Global, long-term cooling has been cast a major role in driving these cell size decreases. Despite overall correspondence between long-term trends, however, it's becoming more and more clear that not all phytoplankton dance to the same tune. The latter is particularly evident when looking at different coccolithophore lineages. Here, I will review the state-of-the-art and highlight some open avenues that are wo...
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Calcifying haptophytes (coccolithophores) sequester carbon in the form of organic and inorganic cellular components (coccoliths). We examined the effect of phosphorus (P) limitation and heat stress on particulate organic and inorganic... more
Calcifying haptophytes (coccolithophores) sequester carbon in the form of organic and inorganic cellular components (coccoliths). We examined the effect of phosphorus (P) limitation and heat stress on particulate organic and inorganic carbon (calcite) production in the coccolithophore <i>Emiliania huxleyi</i>. Both environmental stressors are related to rising CO<sub>2</sub> levels and affect carbon production in marine microalgae, which in turn impacts biogeochemical cycling. Using semi-continuous cultures, we show that P-limitation and heat stress decrease the calcification rate in <i>E. huxleyi</i>. This could lessen the ballasting effect of coccoliths and weaken carbon export out of the photic zone. However, using batch cultures, we show that different culturing approaches (batch versus semi-continuous) induce different physiologies. This affects the ratio of inorganic (PIC) to organic (POC) carbon and complicates general predictions on the ef...
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During the Eocene-Oligocene transition (EOT), the world changed from a high-pCO 2 warm Eocene world to a cool, lower pCO 2 Oligocene world, oceanic phytoplankton was affected in various ways (Persico & Villa, 2004; Dunkley Jones et al.,... more
During the Eocene-Oligocene transition (EOT), the world changed from a high-pCO 2 warm Eocene world to a cool, lower pCO 2 Oligocene world, oceanic phytoplankton was affected in various ways (Persico & Villa, 2004; Dunkley Jones et al., 2008; Henderiks & Pagani, 2008). To unravel the relations between changes in climatic and calcareous nannofossil assemblages, we studied a high-resolution succession spanning the Eocene-Oligocene transition (32.7-34.3Ma) at ODP Site 1263. The analysis revealed a distinct decrease in nannoplankton absolute abundance (N/g) and in mean coccolith size across the E-O boundary (34 Ma). The absolute abundance of small to medium-sized Cyclicargolithus did not vary much in the studied interval, but that of large-sized Reticulofenestra and Dictyococcites decreased abruptly across the E-O. This is confirmed by principal component analysis, with PC1 (36% of variance) loaded negatively by small to medium-sized species and positively by large species. Thus, the mo...
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Pre-Quaternary paleoclimate studies in Australia mainly focus on terrestrial records from the southeastern part of the continent. IODP Expedition 356 drilled on the northwestern Australian shelf, yielding Miocene-Pleistocene paleoclimate... more
Pre-Quaternary paleoclimate studies in Australia mainly focus on terrestrial records from the southeastern part of the continent. IODP Expedition 356 drilled on the northwestern Australian shelf, yielding Miocene-Pleistocene paleoclimate records in an area where climate archives are scarce. Post-expedition research revealed a dry-to–humid transition across the latest Miocene and early Pliocene (start of the "Humid Interval"). However, the complex tectonic history of the area makes these interpretations challenging. Here, we investigate late Miocene to early Pliocene sediment cores from two sites that are only 100 km apart, but situated in two adjacent basins (Northern Carnarvon and Roebuck Basins). Combining lithofacies study, time-series analysis of NGR potassium content (K wt%), calcareous nannofossil abundance counts (N/g) and accumulation rates (N/cm2/kyr), as well as benthic foraminifera δ¹⁸O, this work disentangles the complex interplay between basin evolution and cl...
Research Interests: Geology and Foraminifera
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Long-term alkenone-based pCO2 records are widely applied in paleoclimate evaluations. These pCO2 estimates are based on records of the carbon isotope fractionation that occurs during marine haptophyte photosynthesis (epsilon p37:2). In... more
Long-term alkenone-based pCO2 records are widely applied in paleoclimate evaluations. These pCO2 estimates are based on records of the carbon isotope fractionation that occurs during marine haptophyte photosynthesis (epsilon p37:2). In addition to the concentration of aqueous CO2 (CO2(aq)) the magnitude of epsilon p37:2 is also influenced by algal growth rates and cell geometry. To date, the influence of haptophyte cell geometry on the expression of ancient epsilon p37:2 values has received little attention. This study evaluates changes in cell geometry of ancient alkenone-producing algae at Deep See Drilling Project Site 516 in the southwest Atlantic Ocean by analyzing individual coccolith dimensions, which are proportional to algal cell volume and surface area. We show that during part of the early Miocene, mean cell sizes of alkenone-producing algae were smaller relative to modern Emiliania huxleyi. Cell size variations coincide with significant changes in epsilon p37:2, with a d...