G.-J. Reichart

Koninklijk Nederlands Instituut voor Onderzoek der Zee - NIOZ, Burg, North Holland, Netherlands

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Publications (160)291.02 Total impact

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    ABSTRACT: Live (Rose Bengal stained) benthic foraminifera from the Murray Ridge, within and below the northern Arabian Sea oxygen minimum zone (OMZ), were studied in order to determine the relationship between faunal composition, bottom water oxygenation (BWO), pore water chemistry and organic matter (organic carbon and phytopigment) distribution. A series of multicores were recovered from a ten-station oxygen (BWO: 2-78 μM) and bathymetric (885-3010 m depth) transect during the winter monsoon in January 2009. Foraminifera were investigated from three different size fractions (63-125 μm, 125-150 μm and >150 μm). The larger foraminifera (>125 μm) were strongly dominated by agglutinated species (e.g. Reophax spp.). In contrast, in the 63-125 μm fraction, calcareous taxa were more abundant, especially in the core of the OMZ. On the basis of a principal components analysis, three foraminiferal groups were identified and correlated to the environmental parameters by canonical correspondence analysis. The faunas from the shallowest stations, in the core of the OMZ (BWO: 2 μM), were composed of "low oxygen" species, typical of the Arabian Sea OMZ (e.g. Rotaliatinopsis semiinvoluta, Praeglobobulimina sp., Bulimina exilis, Uvigerina peregrina type parva). These taxa are adapted to the very low BWO conditions and to high phytodetritus supplies. The transitional group, typical for the lower part of the OMZ (BWO: 5-16 μM), is composed of species that are tolerant as well to low-oxygen concentrations, but may be less critical with respect to organic supplies (e.g. Globocassidulina subglobosa, Ehrenbergina trigona). Below the OMZ (BWO: 26-78 μM), where food availability is more limited and becomes increasingly restricted to surficial sediments, cosmopolitan calcareous taxa were present, such as Bulimina aculeata, Melonis barleeanus, Uvigerina peregrina and Epistominella exigua. Miliolids were uniquely observed in this last zone, reflecting the higher BWO and/or lower organic input. At these deeper sites, the faunas exhibit a clear succession of superficial, intermediate and deep infaunal microhabitats, which can be linked to the deeper oxygen and nitrate penetration into the sediment.
    Biogeosciences 02/2014; 11:1155-1175. · 3.75 Impact Factor
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    ABSTRACT: Unusual C35 to C38 alkenones were identified in mid-Holocene (8—3.5 kyr BP) sediments from a restricted estuary in southwest Florida (Charlotte Harbor). The distribution is dominated by a C36 diunsaturated (ω15,20) ethyl ketone, which is identical to the one present in Black Sea Unit 2 sediments. Other unusual alkenones were tentatively assigned as a C35:2 (ω15,20) methyl ketone, a C37:2 (ω17,22) methyl ketone and a C38:2 (ω17,22) ethyl ketone. In late Holocene sediments <3.5 kyr BP, the common C37 to C39 alkenones were found. Compound-specific 14C, 13C, and D isotope measurements were used to constrain the possible origin of the alkenones. Conventional radiocarbon ages of alkenones and higher plant-derived long chain n-alcohols indicate no significant difference in age between mid-Holocene alkenones and higher plant n-alcohols. Both alcohols and alkenones are offset versus calibrated ages of shell fragments in the same sediment core, which suggests they are pre-aged by 500—800 years, implying resuspension and redistribution of the fine-grained sedimentary particles with which they are associated. The hydrogen isotopic (δD) composition (-190 to -200‰) of the C37 and C38 alkenones in the late Holocene sediments is in line with values for coastal haptophytes in brackish water. However, the unusual C36 and C38 alkenones from the mid Holocene sediments are enriched in D (by ca. 100‰) vs. the late Holocene alkenones. Also, δ13C values of mid-Holocene alkenones were consistently offset compared to late Holocene alkenones (-21 to -22‰ and -22 to -23‰, respectively). We suggest that the alkenones in Charlotte Harbor are produced by a so far unknown alkenone-producing haptophyte.
    Organic Geochemistry 01/2014; · 2.52 Impact Factor
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    ABSTRACT: In this paper, we review the current understanding of biomineralization in Rotaliid foraminifera. Ideas on the mechanisms responsible for the flux of Ca2 + and inorganic carbon from seawater into the test were originally based on light and electron microscopic observations of calcifying foraminifera. From the 1980’s onward, tracer experiments, fluorescent microscopy and high-resolution test geochemical analysis have added to existing calcification models. Despite recent insights, no general consensus on the physiological basis of foraminiferal biomineralization exists. Current models include seawater vacuolization, transmembrane ion transport, involvement of organic matrices and/or pH regulation, although the magnitude of these controls remain to be quantified. Disagreement between currently available models may be caused by use of different foraminiferal species as subject for biomineralization experiments and/or lack of a more systematic approach to study (dis)similarities between taxa. In order to understand foraminiferal controls on element incorporation and isotope fractionation, and thereby improve the value of foraminifera as paleoceanographic proxies, it is necessary to identify key processes in foraminiferal biomineralization and formulate hypotheses regarding the involved physiological pathways to provide directions for future research.
    Earth-Science Reviews 01/2014; · 7.34 Impact Factor
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    ABSTRACT: Biological activity introduces variability in element incorporation during calcification and thereby decreases the precision and accuracy when using foraminifera as geochemical proxies in paleoceanography. This so-called 'vital effect' consists of organismal and environmental components. Whereas organismal effects include uptake of ions from seawater and subsequent processing upon calcification, environmental effects include migration- and seasonality-induced differences. Triggering asexual reproduction and culturing juveniles of the benthic foraminifer Ammonia tepida under constant, controlled conditions allows environmental and genetic variability to be removed and the effect of cell-physiological controls on element incorporation to be quantified. Three groups of clones were cultured under constant conditions while determining their growth rates, size-normalized weights and single-chamber Mg/Ca and Sr/Ca using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Results show no detectable ontogenetic control on the incorporation of these elements in the species studied here. Despite constant culturing conditions, Mg/Ca varies by a factor of ~ 4 within an individual foraminifer while intra-individual Sr/Ca varies by only a factor of 1.6. Differences between clone groups were similar to the intra-clone group variability in element composition, suggesting that any genetic differences between the clone-groups studied here do not affect trace element partitioning. Instead, variability in Mg/Ca appears to be inherent to the process of bio-calcification itself. The variability in Mg/Ca between chambers shows that measurements of at least 6 different chambers are required to determine the mean Mg/Ca value for a cultured foraminiferal test with a precision of ≤ 10%.
    Marine Micropaleontology 01/2014; · 1.93 Impact Factor
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    ABSTRACT: The Paleocene–Eocene Thermal Maximum (PETM, ∼ 56 Ma) was a ∼ 200 kyr episode of global warming, associated with massive injections of 13 C-depleted carbon into the ocean–atmosphere system. Although climate change during the PETM is relatively well constrained, effects on marine oxygen concentrations and nutrient cycling remain largely unclear. We identify the PETM in a sediment core from the US margin of the Gulf of Mexico. Biomarker-based paleotemperature proxies (methylation of branched tetraether–cyclization of branched tetraether (MBT–CBT) and TEX 86) indicate that continental air and sea surface temperatures warmed from 27–29 to ∼ 35 • C, although variations in the relative abundances of terrestrial and marine biomarkers may have influenced these estimates. Vegetation changes, as recorded from pollen assemblages, support this warming. The PETM is bracketed by two unconformities. It over-lies Paleocene silt-and mudstones and is rich in angular (thus in situ produced; autochthonous) glauconite grains, which indicate sedimentary condensation. A drop in the rel-ative abundance of terrestrial organic matter and changes in the dinoflagellate cyst assemblages suggest that rising sea level shifted the deposition of terrigenous material land-ward. This is consistent with previous findings of eustatic sea level rise during the PETM. Regionally, the attribution of the glauconite-rich unit to the PETM implicates the dating of a primate fossil, argued to represent the oldest North American specimen on record. The biomarker isorenieratene within the PETM indicates that euxinic photic zone conditions developed, likely sea-sonally, along the Gulf Coastal Plain. A global data com-pilation indicates that O 2 concentrations dropped in all ocean basins in response to warming, hydrological change, and carbon cycle feedbacks. This culminated in (seasonal) anoxia along many continental margins, analogous to mod-ern trends. Seafloor deoxygenation and widespread (sea-sonal) anoxia likely caused phosphorus regeneration from suboxic and anoxic sediments. We argue that this fueled shelf eutrophication, as widely recorded from microfossil stud-ies, increasing organic carbon burial along many continental Published by Copernicus Publications on behalf of the European Geosciences Union. 1422 A. Sluijs et al.: Warming, euxinia and sea level rise during the PETM margins as a negative feedback to carbon input and global warming. If properly quantified with future work, the PETM offers the opportunity to assess the biogeochemical effects of enhanced phosphorus regeneration, as well as the timescales on which this feedback operates in view of modern and fu-ture ocean deoxygenation.
    Climate of the Past 01/2014; 10:1421-1439. · 3.56 Impact Factor
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    ABSTRACT: The Paleocene/Eocene Thermal Maximum (PETM, ~56 Ma) was a ~200 kyr episode of global warming, associated with massive injections of 13C-depleted carbon into the ocean-atmosphere system. Although climate change during the PETM is relatively well constrained, effects on marine oxygen and nutrient cycling remain largely unclear. We identify the PETM in a sediment core from the US margin of the Gulf of Mexico. Biomarker-based paleotemperature proxies (MBT/CBT and TEX86) indicate that continental air and sea surface temperatures warmed from 27-29 °C to ~35 °C, although variations in the relative abundances of terrestrial and marine biomarkers may have influenced the record. Vegetation changes as recorded from pollen assemblages supports profound warming. Lithology, relative abundances of terrestrial vs. marine palynomorphs as well as dinoflagellate cyst and biomarker assemblages indicate sea level rise during the PETM, consistent with previously recognized eustatic rise. The recognition of a maximum flooding surface during the PETM changes regional sequence stratigraphic interpretations, which allows us to exclude the previously posed hypothesis that a nearby fossil found in PETM-deposits represents the first North American primate. Within the PETM we record the biomarker isorenieratane, diagnostic of euxinic photic zone conditions. A global data compilation indicates that deoxygenation occurred in large regions of the global ocean in response to warming, hydrological change, and carbon cycle feedbacks, particularly along continental margins, analogous to modern trends. Seafloor deoxygenation and widespread anoxia likely caused phosphorus regeneration from suboxic and anoxic sediments. We argue that this fuelled shelf eutrophication, as widely recorded from microfossil studies, increasing organic carbon burial along continental margins as a negative feedback to carbon input and global warming. If properly quantified with future work, the PETM offers the opportunity to assess the biogeochemical effects of enhanced phosphorus regeneration, as well as the time-scales on which this feedback operates in view of modern and future ocean deoxygenation.
    Climate of the Past Discussions 12/2013; 9(6):6459-6494.
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    ABSTRACT: Salinity and temperature determine seawater density, and differences in both thereby control global thermo- haline circulation. Whereas numerous proxies have been calibrated and applied to reconstruct temperature, a direct and independent proxy for salinity is still missing. Ideally, a new proxy for salinity should target one of the direct constituents of dissolved salt, such as [Na+] or [Cl−]. This study investigates the impact of salinity on foraminiferal Na / Ca values by laser ablation ICP-MS analyses of specimens of the benthic foraminifer Ammonia tepida cultured at a range of salinities (30.0–38.6). Foraminifera at lower salinities (30.0 and 32.5) added more chambers (10–11) to their test over the course of the culturing experiment than those maintained at higher salinities (36.1, 7–8 chambers, and 38.6, 6–7 chambers), suggesting that growth rates in this species are promoted by lower salinities. The Na / Ca of cultured specimens correlates significantly with seawater salinity (Na / Ca =0.22S–0.75, R2=0.96,p<0.01) and size. Values for Na / Ca and D_Na vary between 5.17 and 9.29 mmol mol−1and 0.12–0.16×10−3, which are similar to values from inorganic precipitation experiments. The significant correlation between test size and Na / Ca results from co-variation with salinity. This implies that foraminiferal Na / Ca could serve as a robust and independent proxy for salinity, enabling salinity reconstructions independent of calcitic δ18O.
    Biogeosciences 10/2013; 10:6375-6387. · 3.75 Impact Factor
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    ABSTRACT: Live (Rose Bengal stained) benthic foraminifera from the Murray Ridge, within and below the northern Arabian Sea Oxygen Minimum Zone (OMZ), were studied in order to determine the relationship between faunal composition, bottom-water oxygenation (BWO), pore-water chemistry and organic matter (organic carbon and phytopigment) distribution. A series of multicores were recovered from a ten-station oxygen (BWO: 2-78 μM) and bathymetric (885-3010 m depth) transect during the winter monsoon in January 2009. Foraminifera were investigated from three different size fractions (63-125 μm, 125-150 μm and > 150 μm). The larger foraminifera (> 125 μm) were strongly dominated by agglutinated species (e.g. Reophax spp.). In contrast, in the 63-125 μm fraction, calcareous taxa were more abundant, especially in the core of the OMZ, suggesting an opportunistic behaviour. On the basis of a Principal Component Analysis, three foraminiferal groups were identified, reflecting the environmental parameters along the study transect. The faunas from the shallowest stations, in the core of the OMZ (BWO: 2 μM), were composed of "low oxygen" species, typical of the Arabian Sea OMZ (e.g., Rotaliatinopsis semiinvoluta, Praeglobobulimina spp. , Bulimina exilis, Uvigerina peregrina typeparva). These taxa are adapted to the very low BWO conditions and to high phytodetritus supplies. The transitional group, typical for the lower part of the OMZ (BWO: 5-16 μM), is composed of more cosmopolitan taxa tolerant to low-oxygen concentrations (Globocassidulina subglobosa, Ehrenbergina trigona). Below the OMZ (BWO: 26-78 μM), where food availability is more limited and becomes increasingly restricted to surficial sediments, more cosmopolitan calcareous taxa were present, such as Bulimina aculeata, Melonis barleeanus, Uvigerina peregrina and Epistominella exigua. Miliolids were uniquely observed in this last group, reflecting the higher BWO. At these deeper sites, the faunas exhibit a clear depth succession of superficial, intermediate and deep-infaunal microhabitats, because of the deeper oxygen and nitrate penetration into the sediment.
    Biogeosciences Discussions 09/2013; 10(9):15257-15304.
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    07/2013;
  • J. C. Wit, G. J. Reichart, G. M. Ganssen
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    ABSTRACT: resolution at which foraminiferal stable isotopes are applied in paleo-environmental studies is ever increasing, resulting in continuous sampling of sediment cores. The resolution of such continuously sampled records depends on the rate of sedimentation of foraminiferal shells in its relation to the intensity of bioturbation. Bioturbation essentially mixes sediment layers of different age, altering the primary climate signal, thereby impacting the accuracy of both the timing and magnitude of reconstructed climate changes. A new approach to assess and correct the impact of bioturbation is investigated here, based on the δ18O of individual specimens of planktonic foraminifera Globorotalia inflata from a series of boxcore samples in the Eastern North Atlantic. Average δ18O values decrease southward from 1.62 to 1.07‰ with the exception of site T86-11 (1.35‰). The δ18O distribution of each station can be fitted with a uni- to polymodal distribution. A nonunimodal distribution strongly suggests admixing of bioturbated individuals. Quantification of these distributions allows deconvolving the original and bioturbated signals and subsequently provides a correction for bioturbation.
    Geochemistry Geophysics Geosystems 04/2013; 14(4):1312-1320. · 2.94 Impact Factor
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    ABSTRACT: Burial of organic matter (OM) plays an important role in marine sediments, linking the short-term, biological carbon cycle with the long-term, geological subsurface cycle. It is well established that low-oxygen conditions promote organic carbon burial in marine sediments. However, the mechanism remains enigmatic. Here we report biochemical quality, microbial degradability, OM preservation and accumulation along an oxygen gradient in the Indian Ocean. Our results show that more OM, with biochemically higher quality, accumulates under low oxygen conditions. Nevertheless, microbial degradability does not correlate with the biochemical quality of OM. This decoupling of OM biochemical quality and microbial degradability, or bioavailability, violates the ruling paradigm that higher quality implies higher microbial processing. The inhibition of bacterial OM remineralisation may play an important role in the burial of organic matter in marine sediments and formation of oil source rocks.
    Biogeosciences 02/2013; 10:1131-1141. · 3.75 Impact Factor
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    ABSTRACT: Assessing the impact of climate change and anthropogenic activity on Florida coastal areas requires a thorough understanding of natural climate variability. The available instrumental record, however, is too short and too limited to capture the full range of natural variability. In order to provide additional data on the natural state of the climate system and to evaluate the influence of human impact, we reconstructed climatic and environmental changes of the past 300 years. Pre- (before 1900 ad) and post-human impact conditions were compared in Rookery Bay, a subtropical, southern Florida estuary and its bordering wetland system. Biomarkers from terrestrial and aquatic environments were used to reconstruct temperature, runoff, and aquatic productivity. Pre-anthropogenic conditions before 1750 ad indicate a relatively large contribution of mangrove-derived organic matter, locally decreasing at the end of this period. After 1750 ad follows a relatively stable period in which biomarker concentrations indicate relatively low levels of runoff and aquatic production. Enhanced anthropogenic activities, such as land clearance and hydrological alterations, end this period of stability by altering the hydrological conditions. This leads to a more dynamic system which is more sensitive to disturbances of vegetation and drainage, as evidenced by peak terrestrial biomarker fluxes during the twentieth century. These episodes of enhanced runoff resulted in eutrophication and algal blooms in Rookery Bay. Natural climate phenomena, such as a positive AMO phase and hurricane activity, might have added to ongoing processes during the twentieth century.
    Estuaries and Coasts 01/2013; 36(1). · 2.56 Impact Factor
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    ABSTRACT: The reconstruction of past temperatures is often achieved through measuring the Mg/Ca value of foraminiferal test carbonate. The diversity in foraminiferal Mg/Ca-temperature calibrations suggests that there is also a biological control on this proxy. This study presents a new Mg/Ca-temperature calibration for the benthic foraminifer Bulimina marginata, based on cultures under a range of temperatures (4-14 °C). Measured Mg/Ca values for B. marginata correlate with temperature (Mg/Ca = (1.10 ± 0.10) e(0.045±0.009)T, R2 = 0.28 p < 0.01). The inter-individual variability is, however, also significant (standard deviation is 10-35% of the average). Before applying this or any calibration, the effect of the inter-individual variability on the accuracy of the Mg/Ca-temperature calibration has to be evaluated. The inter-individual variability is quantified and split into three components, namely (1) an analytical error, (2) an environmental effect and (3) a vital effect. The effect of inter-individual variability on the accuracy of Mg/Ca-temperature calibrations depends on the sensitivity of the calibration used and the number of individuals measured (temperature uncertainty = (0.33 · N-0.50)/sensitivity). The less sensitive a calibration, the greater is the impact of inter-individual variability, which can partly be circumvented by measuring more individuals. This study shows the link between inter-individual variability and sensitivity and quantifies their influence on the accuracy of Mg/Ca-temperature calibrations. Differences in the sensitivity of the Mg/Ca-temperature calibration of foraminifera may depend on the environmental conditions in which foraminifera live and their concurring ecological strategies.
    Biogeosciences 09/2012; 9(9):3693-3704. · 3.75 Impact Factor
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    ABSTRACT: Benthic foraminiferal assemblages were investigated from two sites along the axis of the Cassidaigne Canyon (NW Mediterranean Sea). Both areas are contaminated by bauxite red mud enriched in iron, titanium, vanadium and chromium. These elemental enrichments are related to bauxite-derived minerals and various amorphous phases. At the shallowest station located very close to the pipe outlet, the benthic living foraminiferal community is characterised by a very low diversity and by an unusual dominance of Gyroidina umbonata and Bulimina marginata. The mechanical stress related to downslope transport of red mud is a likely source of hydro-sedimentary pollution precluding the settlement of diverse fauna. The living and dead foraminiferal faunas from the deepest site are typical of oligo-mesotrophic conditions prevailing in natural environments. There, bauxite residues have obviously no environmental impact on foraminiferal faunas. The bioavailability of trace metals is likely low as elemental enrichments were not observed in foraminiferal test chemistry.
    Marine pollution bulletin 07/2012; 64(9):1895-910. · 2.63 Impact Factor
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    ABSTRACT: In this study, we investigate phosphorus (P) and iron (Fe) cycling in sediments along a depth transect from within to well below the oxygen minimum zone (OMZ) in the northern Arabian Sea (Murray Ridge). Pore-water and solid-phase analyses show that authigenic formation of calcium phosphate minerals (Ca-P) is largely restricted to where the OMZ intersects the seafloor topography, likely due to higher depositional fluxes of reactive P. Nonetheless, increased ratios of organic carbon to organic P (Corg/Porg) and to total reactive P (Corg/Preactive) in surface sediments indicate that the overall burial efficiency of P relative to Corg decreases under the low bottom water oxygen concentrations (BWO) in the OMZ. The relatively constant Fe/Al ratio in surface sediments along the depth transect suggest that corresponding changes in Fe burial are limited. Sedimentary pyrite contents are low throughout the ~25 cm sediment cores at most stations, as commonly observed in the Arabian Sea OMZ. However, pyrite is an important sink for reactive Fe at one station in the OMZ. A reactive transport model (RTM) was applied to quantitatively investigate P and Fe diagenesis at an intermediate station at the lower boundary of the OMZ (bottom water O2: ~14 μmol L-1). The RTM results contrast with earlier findings in showing that Fe redox cycling can control authigenic apatite formation and P burial in Arabian Sea sediment. In addition, results suggest that a large fraction of the sedimentary Ca-P is not authigenic, but is instead deposited from the water column and buried. Dust is likely a major source of this Ca-P. Inclusion of the unreactive Ca-P pool in the Corg/P ratio leads to an overestimation of the burial efficiency of reactive P relative to Corg along the depth transect. Moreover, the unreactive Ca-P accounts for ~85% of total Ca-P burial. In general, our results reveal large differences in P and Fe chemistry between stations in the OMZ, indicating dynamic sedimentary conditions under these oxygen-depleted waters.
    Biogeosciences 07/2012; 9(7):2603-2624. · 3.75 Impact Factor
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    ABSTRACT: The reconstruction of past temperatures is often achieved through measuring the Mg/Ca value of foraminiferal test carbonate. The diversity in foraminiferal Mg/Ca-temperature calibrations suggests that there is also a biological control on this proxy. This study presents a new Mg/Ca-temperature calibration for the benthic foraminifer Bulimina marginata, based on cultures under a range of temperatures (4-14 ° C). Measured Mg/Ca values for B. marginata correlate well with temperature (Mg/Ca = 1.10 ± 0.10e0.045 ± 0.009T, R2=0.28, p<0.01). The inter-individual variability is, however, also significant (standard deviation is 10-35 % of the average). Before applying this or any calibration, the effect of the inter-individual variability on the accuracy of the Mg/Ca-temperature calibration has to be evaluated. The inter-individual variability is quantified and split in three components, namely (1) an analytical error; (2) an environmental effect and (3) a vital effect. The effect of inter-individual variability on the accuracy of Mg/Ca-temperature calibrations is depending on the sensitivity of the used calibration and the number of individuals measured (Temperature uncertainty = (0.33 · N-0.50)/sensitivity). The less sensitive a calibration, the greater is the impact of inter-individual variability. This can partly be circumvented by measuring more individuals. Differences in sensitivity may depend on the stability of the environment in which the foraminifera live and the concurring ecological strategy. This study shows the link between inter-individual variability en sensitivity and their influence on the accuracy of Mg/Ca-temperature calibrations.
    Biogeosciences Discussions 04/2012; 9(4):4947-4977.
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    ABSTRACT: Reconstructing changes in thermo-haline circulation critically relies on our ability to quantify both past temperature and salinity. Several proxies have been developed and implemented for temperature. However, lacking reliable proxies for past salinity remain a major obstacle in fully reconstructing the paleoceanographic environment. Indirect reconstructions rely on combining temperature and ice volume assessments to deconvolve surface water oxygen stable isotope values, which are then used to calculate salinity. This approach relies on local calibration and is inherently inaccurate as progressive errors add to the uncertainty. The lack of an accurate more direct method to estimate past seawater salinity thus currently limits reconstruction of past ocean circulation. Here we show a new approach to independently and accurately reconstruct seawater salinity using Na incorporation in foraminiferal test carbonate. Foraminifera cultured under controlled conditions at different salinities show that test calcite Na/Ca values increase linearly with salinity. Application of this method to foraminifers living during a period of known reduced suface water salinity, i.e. sapropel S5 (~125 ka) from the Eastern Mediterranean, indicates that salinity dropped by 6 units. This salinity decrease is in line with previous reconstructions for this time interval. Culturing results and paleoceanographic application thus show that foraminiferal Na/Ca values provide an accurate and robust tool to reconstruct past salinity changes.
    04/2012;

Publication Stats

1k Citations
291.02 Total Impact Points

Institutions

  • 2009–2014
    • Koninklijk Nederlands Instituut voor Onderzoek der Zee - NIOZ
      • Department of Marine Organic Biogeochemistry (BGC)
      Burg, North Holland, Netherlands
    • Radboud University Nijmegen
      • Department of Microbiology
      Nijmegen, Provincie Gelderland, Netherlands
  • 1997–2014
    • Universiteit Utrecht
      • • Faculty of Geosciences
      • • Department of Earth Sciences
      • • Laboratory of Palaeobotany and Palynology
      • • Institute of Earth Sciences Utrecht (IVAU)
      Utrecht, Utrecht, Netherlands
  • 2011
    • De Geological Survey of the Netherlands
      Utrecht, Utrecht, Netherlands
  • 2003–2011
    • Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research
      Bremerhaven, Bremen, Germany