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4. Climate change, society, and pandemic disease in Roman Italy between 200 BCE and 600 CE

Author

Zonneveld, Karin A.F., Harper, Kyle, Klügel, Andreas, Chen, Liang, de Lange, Gert, Versteegh, Gerard J.M., Zonneveld, Karin A.F., Harper, Kyle, Klügel, Andreas, Chen, Liang, de Lange, Gert, and Versteegh, Gerard J.M.

Abstract

Records of past societies confronted with natural climate change can illuminate social responses to environmental stress and environment-disease connections, especially when locally constrained high-temporal resolution paleoclimate reconstructions are available. We present a temperature and precipitation reconstruction for ~200 BCE to ~600 CE, from a southern Italian marine sedimentary archive-the first high-resolution (~3 years) climate record from the heartland of the Roman Empire, stretching from the so-called Roman Climate Optimum to the Late Antique Little Ice Age. We document phases of instability and cooling from ~100 CE onward but more notably after ~130 CE. Pronounced cold phases between ~160 to 180 CE, ~245 to 275 CE, and after ~530 CE associate with pandemic disease, suggesting that climate stress interacted with social and biological variables. The importance of environment-disease dynamics in past civilizations underscores the need to incorporate health in risk assessments of climate change.

Published
2024

5. Climate change, society, and pandemic disease in Roman Italy between 200 BCE and 600 CE

Author

IVAU: Instituut voor Aardwetenschappen Utrecht, Geochemistry, Zonneveld, Karin A.F., Harper, Kyle, Klügel, Andreas, Chen, Liang, de Lange, Gert, Versteegh, Gerard J.M., IVAU: Instituut voor Aardwetenschappen Utrecht, Geochemistry, Zonneveld, Karin A.F., Harper, Kyle, Klügel, Andreas, Chen, Liang, de Lange, Gert, and Versteegh, Gerard J.M.

Published
2024

10. The 2.1 Ga old Francevillian biota: biogenicity, taphonomy and biodiversity.

Author

El Albani, Abderrazak, Bengtson, Stefan, Canfield, Donald E, Riboulleau, Armelle, Rollion Bard, Claire, Macchiarelli, Roberto, Ngombi Pemba, Lauriss, Hammarlund, Emma, Meunier, Alain, Moubiya Mouele, Idalina, Benzerara, Karim, Bernard, Sylvain, Boulvais, Philippe, Chaussidon, Marc, Cesari, Christian, Fontaine, Claude, Chi-Fru, Ernest, Garcia Ruiz, Juan Manuel, Gauthier-Lafaye, François, Mazurier, Arnaud, Pierson-Wickmann, Anne Catherine, Rouxel, Olivier, Trentesaux, Alain, Vecoli, Marco, Versteegh, Gerard JM, White, Lee, Whitehouse, Martin, and Bekker, Andrey

Subjects
Biodiversity, Phylogeny, Fossils, Gabon, Biological Evolution, Origin of Life, General Science & Technology
Abstract

The Paleoproterozoic Era witnessed crucial steps in the evolution of Earth's surface environments following the first appreciable rise of free atmospheric oxygen concentrations ∼2.3 to 2.1 Ga ago, and concomitant shallow ocean oxygenation. While most sedimentary successions deposited during this time interval have experienced thermal overprinting from burial diagenesis and metamorphism, the ca. 2.1 Ga black shales of the Francevillian B Formation (FB2) cropping out in southeastern Gabon have not. The Francevillian Formation contains centimeter-sized structures interpreted as organized and spatially discrete populations of colonial organisms living in an oxygenated marine ecosystem. Here, new material from the FB2 black shales is presented and analyzed to further explore its biogenicity and taphonomy. Our extended record comprises variably sized, shaped, and structured pyritized macrofossils of lobate, elongated, and rod-shaped morphologies as well as abundant non-pyritized disk-shaped macrofossils and organic-walled acritarchs. Combined microtomography, geochemistry, and sedimentary analysis suggest a biota fossilized during early diagenesis. The emergence of this biota follows a rise in atmospheric oxygen, which is consistent with the idea that surface oxygenation allowed the evolution and ecological expansion of complex megascopic life.

Published
2014

11. The 2.1 Ga Old Francevillian Biota: Biogenicity, Taphonomy and Biodiversity

Author

Albani, Abderrazak El, Bengtson, Stefan, Canfield, Donald E, Riboulleau, Armelle, Bard, Claire Rollion, Macchiarelli, Roberto, Pemba, Lauriss Ngombi, Hammarlund, Emma, Meunier, Alain, Mouele, Idalina Moubiya, Benzerara, Karim, Bernard, Sylvain, Boulvais, Philippe, Chaussidon, Marc, Cesari, Christian, Fontaine, Claude, Chi-Fru, Ernest, Ruiz, Juan Manuel Garcia, Gauthier-Lafaye, François, Mazurier, Arnaud, Pierson-Wickmann, Anne Catherine, Rouxel, Olivier, Trentesaux, Alain, Vecoli, Marco, Versteegh, Gerard JM, White, Lee, Whitehouse, Martin, and Bekker, Andrey

Subjects
Biodiversity, Biological Evolution, Fossils, Gabon, Origin of Life, Phylogeny, General Science & Technology
Abstract

The Paleoproterozoic Era witnessed crucial steps in the evolution of Earth's surface environments following the first appreciable rise of free atmospheric oxygen concentrations ∼2.3 to 2.1 Ga ago, and concomitant shallow ocean oxygenation. While most sedimentary successions deposited during this time interval have experienced thermal overprinting from burial diagenesis and metamorphism, the ca. 2.1 Ga black shales of the Francevillian B Formation (FB2) cropping out in southeastern Gabon have not. The Francevillian Formation contains centimeter-sized structures interpreted as organized and spatially discrete populations of colonial organisms living in an oxygenated marine ecosystem. Here, new material from the FB2 black shales is presented and analyzed to further explore its biogenicity and taphonomy. Our extended record comprises variably sized, shaped, and structured pyritized macrofossils of lobate, elongated, and rod-shaped morphologies as well as abundant non-pyritized disk-shaped macrofossils and organic-walled acritarchs. Combined microtomography, geochemistry, and sedimentary analysis suggest a biota fossilized during early diagenesis. The emergence of this biota follows a rise in atmospheric oxygen, which is consistent with the idea that surface oxygenation allowed the evolution and ecological expansion of complex megascopic life.

Published
2014

12. The dinoflagellate cyst genera Achomosphaera Evitt 1963 and Spiniferites Mantell 1850 in Pliocene to modern sediments : a summary of round table discussions

Author

Mertens, Kenneth Neil, Van Nieuwenhove, Nicolas, Gurdebeke, Pieter R., Aydin, Hilal, Bogus, Kara, Bringué, Manuel, Dale, Barrie, De Schepper, Stijn, de Vernal, Anne, Ellegaard, Marianne, Grothe, Arjen, Gu, Haifeng, Head, Martin J., Heikkilä, Maija, Limoges, Audrey, Londeix, Laurent, Louwye, Stephen, Marret, Fabienne, Masure, Edwige, Matsuoka, Kazumi, Mudie, Peta J., Penaud, Aurélie, Pospelova, Vera, Price, Andrea Michelle, Ribeiro, Sofia, Rochon, André, Sangiorgi, Francesca, Schreck, Michael, Torres, Vladimir, Uzar, Serdar, Versteegh, Gerard J. M., Warny, Sophie, and Zonneveld, Karin

Published
2018

17. (258-260) Proposals to eliminate contradiction between Articles 11.7 and 11.8 and to equate non-fossil with fossil names of dinophytes for purposes of priority

Author

Elbrächter, Malte, Gottschling, Marc, Hoppenrath, Mona, Keupp, Helmut, Kusber, Wolf-Henning, Streng, Michael, Tillmann, Urban, Versteegh, Gerard J. M., Zonneveld, Karin A. F., Elbrächter, Malte, Gottschling, Marc, Hoppenrath, Mona, Keupp, Helmut, Kusber, Wolf-Henning, Streng, Michael, Tillmann, Urban, Versteegh, Gerard J. M., and Zonneveld, Karin A. F.

Published
2023
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27. Dinoflagellate cysts production, excystment and transport in the upwelling off Cape Blanc (NW Africa)

Author

Zonneveld, Karin A. F., Grotheer, Hendrik, and Versteegh, Gerard J. M.

Subjects
Global and Planetary Change, Ocean Engineering, Aquatic Science, Oceanography, Water Science and Technology
Abstract

To extend the understanding of dinoflagellate cysts production, excystment and vertical/lateral transport in the water column, we compared upper water cyst export production with cysts associations and concentrations in the subsurface nepheloid layer, bottom nepheloid layer and deeper water column during active upwelling off Cape Blanc (NW Africa) in August 2020. Export production was collected by two drifting trap surveys; DTS1 in an active upwelling cell for 4 days and DTS2 in an offshore drifting upwelling filament for 2 days. Subsurface, bottom nepheloid layers and deeper waters were sampled by in-situ pumps along two transects perpendicular to the shelf break. During DTS1, light limitation hampered phytoplankton production which might have influenced cyst production negatively due to up- and downward movement of water masses. Cyst export production increased at the rim of the upwelling cell. For DTS2, upwelling filament cyst export production was up to 3 times lower than that of DTS1. Echinidinium delicatum had highest relative and absolute abundances in the active upwelling, Echinidinium zonneveldiae and Bitectatodinium spongium in the upwelling filament, and Impagidinium spp. and cysts of Gymnodinium microreticulatum/nolleri at the most distal stations. Comparison of concentrations of cysts with and without cell contents showed that the majority of cysts hatched before reaching deeper waters and displayed a dormancy period of less than 6 days. About 5% of the living cysts reached deeper waters and/or the ocean floor. Living cysts were transported offshore in the upwelling filament. In case ships exchange ballast waters in the studied region, they will take up laterally transported living cysts. Upon release of the ballast waters in the port of arrival, these cysts have the potential to become “invader species” that can threaten economy and/or health. Lateral transport of cysts was observed in the bottom nepheloid layer and in deeper waters (800 - 1200m depth) with a maximal extension of about 130km off the shelf break. Therefore, sediments in the region will contain a mixture of regionally and locally produced dinoflagellate cysts. This insight contributes to the improvement of environmental reconstructions of the Cape blanc upwelling system based on downcore cyst associations.

Published
2022
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32. Atlas of modern dinoflagellate cyst distribution based on 2405 data points

Author

Zonneveld, Karin A.F., Marret, Fabienne, Versteegh, Gerard J.M., Bogus, Kara, Bonnet, Sophie, Bouimetarhan, Ilham, Crouch, Erica, de Vernal, Anne, Elshanawany, Rehab, Edwards, Lucy, Esper, Oliver, Forke, Sven, Grøsfjeld, Kari, Henry, Maryse, Holzwarth, Ulrike, Kielt, Jean-François, Kim, So-Young, Ladouceur, Stéphanie, Ledu, David, Chen, Liang, Limoges, Audrey, Londeix, Laurent, Lu, S.-H., Mahmoud, Magdy S., Marino, Gianluca, Matsouka, Kazumi, Matthiessen, Jens, Mildenhal, D.C., Mudie, Peta, Neil, H.L., Pospelova, Vera, Qi, Yuzao, Radi, Taoufik, Richerol, Thomas, Rochon, André, Sangiorgi, Francesca, Solignac, Sandrine, Turon, Jean-Louis, Verleye, Thomas, Wang, Yan, Wang, Zhaohui, and Young, Marty

Published
2013
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33. Performance of temperature and productivity proxies based on long-chain alkane-1, mid-chain diols at test: a 5-year sediment trap record from the Mauritanian upwelling

Author

Versteegh, Gerard J. M., Zonneveld, Karin A. F., Hefter, Jens, Romero, Oscar E., Fischer, Gerhard, Mollenhauer, Gesine, Versteegh, Gerard J. M., Zonneveld, Karin A. F., Hefter, Jens, Romero, Oscar E., Fischer, Gerhard, and Mollenhauer, Gesine

Abstract

Proxies based on long-chain alkane-1, mid-chain diols (diol for short) are obtaining increasing interest to reconstruct past upper ocean temperature and productivity. Here we evaluate performance of the sea surface temperature proxies (long-chain diol index (LDI), diol saturation index (DSI), and diol chain length index (DCI)), productivity and upwelling intensity proxies (two diol indices DIR and DIW and the combined diol index (CDI)), and the nutrient diol index (NDI) as a proxy for phosphate and nitrate levels. This evaluation is based on comparison of the diols in sediment trap samples from the upwelling region off NW Africa collected at 1.28 km water depth with daily satellite derived sea surface temperatures (SSTs), subsurface temperatures, productivity, the plankton composition from the trap location, monthly phosphate and nitrate concentrations, wind speed, and wind direction from the nearby Nouadhibou airport. The diol-based SST reconstructions are also compared the long-chain-alkenone-based SST reconstructions. The alkenone SSTs correlate best with satellite SST (r2 D0.60). Amplitude and absolute values agree very well as do the flux-corrected time series averages. For the diol proxies the situation is more complicated. Diol proxies including 1,14 diols lag trade wind speed by 30 d. Since wind is nearly always from the NNE to NNW and induces the upwelling, we relate the variability in these proxies to upwelling-induced processes. Correlation with the abundance of upwelling species and wind speed is best for.

Published
2022

34. Attenuated Total Reflection (ATR) Micro-Fourier Transform Infrared (Micro-FT-IR) Spectroscopy to Enhance Repeatability and Reproducibility of Spectra Derived from Single Specimen Organic-Walled Dinoflagellate Cysts

Author

Meyvisch, Pjotr, R. Gurdebeke, Pieter, Vrielinck, Henk, Mertens, Kenneth, Versteegh, Gerard, Louwye, Stephen, Meyvisch, Pjotr, R. Gurdebeke, Pieter, Vrielinck, Henk, Mertens, Kenneth, Versteegh, Gerard, and Louwye, Stephen

Abstract

The chemical composition of recent and fossil organic-walled dinoflagellate cyst walls and its diversity is poorly understood and analyses on single microscopic specimens are rare. A series of infrared spectroscopic experiments resulted in the proposition of a standardized attenuated total reflection micro-Fourier transform infrared-based method that allows the collection of robust data sets consisting of spectra from individual dinocysts. These data sets are largely devoid of nonchemical artifacts inherent to other infrared spectrochemical methods, which have typically been used to study similar specimens in the past. The influence of sample preparation, specimen morphology and size and spectral data processing steps is also assessed within this methodological framework. As a result, several guidelines are proposed which facilitate the collection and qualitative interpretation of highly reproducible and repeatable spectrochemical data. These, in turn, pave the way for a systematic exploration of dinocyst chemistry and its assessment as a chemotaxonomical tool or proxy.

Published
2022
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38. Recent advances in infrared spectroscopy applied to single specimen dinoflagellate cyst: methodological framework, acquired insights and future perspectives

Author

Meyvisch, Pjotr, Neil Mertens, Kenneth, Vrielinck, Henk, Versteegh, Gerard J. M., Gurdebeke, Pieter, and Louwye, Stephen

Subjects
Fourier-transform infrared spectroscopy, organic-walled dinoflagellate cysts, cyst wall composition, methodology, chemometrics, Earth and Environmental Sciences, Biology and Life Sciences
Abstract

Fourier-transform infrared (FTIR) spectroscopy is a spectrochemical technique able to retrieve macromolecular information from organic materials. When combined with a microscope (micro-FTIR), the bulk (geo)chemical composition of single specimen dinoflagellate cysts (dinocysts) can be determined. Micro-FTIR studies on dinocysts are sparse, partially due to the complexity of the method in terms of possible disruptive variables and the interpretability of the data it provides. Nevertheless, it can be a powerful, rapid, and relatively low-cost tool for retrieving macromolecular information from small organic particles. That is, if a certain degree of methodological insights and control can be ensured. This recently led to the development of a methodological framework (Meyvisch et al. 2021) wherein a wide array of variables are discussed. The result of this study is a method based on attenuated total reflection (ATR) micro-FTIR spectroscopy which allows for the collection of robust spectrochemical datasets, and which will be presented here. Earlier micro-FTIR studies on dinocysts have explored the potential of the method to be used as a chemotaxonomical tool (Bogus et al. 2012), a proxy for trophic affinity (Bogus et al. 2014) and to assess preservation of organic matter in oxic and sulphidic depositional environments (Versteegh et al. 2020). Within the light of the later developed methodological framework, some of these authors’ findings are re- evaluated and supplemented with more elaborate and robust datasets. The overview provided on the current state of this – relatively underexplored – research domain perfectly sets the stage to discuss its future perspectives, with a focus on providing answers to major standing questions regarding the (geo)chemical nature and variability of dinoflagellate cyst walls. Finally, other useful and complementary analytical methods which can contribute to elucidating these problems will be briefly discussed.

Published
2022

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