Rapid global warming and oceanic oxygen deficiency during the Early Jurassic Toarcian Oceanic Anoxic Event at around 183 Ma is associated with a major turnover of marine biota linked to volcanic activity. The impact of the event on land-based ecosystems and the processes that led to oceanic anoxia remain poorly understood. Here we present analyses of spore–pollen assemblages from Pliensbachian–Toarcian rock samples that record marked changes on land during the Toarcian Oceanic Anoxic Event. Vegetation shifted from a high-diversity mixture of conifers, seed ferns, wet-adapted ferns and lycophytes to a low-diversity assemblage dominated by cheirolepid conifers, cycads and Cerebropollenites-producers, which were able to survive in warm, drought-like conditions. Despite the rapid recovery of floras after Toarcian global warming, the overall community composition remained notably different after the event. In shelf seas, eutrophication continued throughout the Toarcian event. This is reflected in the overwhelming dominance of algae, which contributed to reduced oxygen conditions and to a marked decline in dinoflagellates. The substantial initial vegetation response across the Pliensbachian/Toarcian boundary compared with the relatively minor marine response highlights that the impacts of the early stages of volcanogenic global warming were more severe for continental ecosystems than marine ecosystems.
Your institute does not have access to this article
Open Access articles citing this article.
Nature Communications Open Access 17 September 2021
Scientific Reports Open Access 10 January 2020
Subscribe to Nature+
Get immediate online access to the entire Nature family of 50+ journals
Subscribe to Journal
Get full journal access for 1 year
only $8.25 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Get time limited or full article access on ReadCube.
All prices are NET prices.
The authors declare that the data supporting the findings of this study are available within the article and Supplementary Information. All materials (rock samples and slides) are housed in the collections of the Natural History Museum, London.
McElwain, J. C., Wade-Murphy, J. & Hesselbo, S. P. Changes in carbon dioxide during an oceanic anoxic event linked to intrusion into Gondwana coals. Nature 435, 479–482 (2005).
Little, C. T. S. & Benton, M. J. Early Jurassic mass extinction: a global long-term event. Geology 23, 495–498 (1995).
Harries, P. J. & Little, C. T. S. The early Toarcian (Early Jurassic) and the Cenomanian Turonian (Late Cretaceous) mass extinctions: similarities and contrasts. Palaeogeogr. Palaeoclimatol. Palaeoecol. 154, 39–66 (1999).
Gómez, J. J. & Goy, A. Warming-driven mass extinction in the Early Toarcian (Early Jurassic) of northern and central Spain. Correlation with other time-equivalent European sections. Palaeogeogr. Palaeoclimatol. Palaeoecol. 306, 176–195 (2011).
Caruthers, A. H., Smith, P. L. & Gröcke, D. R. The Pliensbachian–Toarcian (Early Jurassic) extinction, a global multi-phased event. Palaeogeogr. Palaeoclimatol. Palaeoecol. 386, 104–118 (2013).
Lu, Z., Jenkyns, H. C. & Rickaby, R. E. M. Iodine to calcium ratios in marine carbonate as a paleo-redox proxy during oceanic anoxic events. Geology 38, 1107–1110 (2010).
Gill, B. C., Lyons, T. W. & Jenkyns, H. C. A global perturbation to the sulfur cycle during the Toarcian Oceanic Anoxic Event. Earth Planet. Sci. Lett. 312, 484–496 (2011).
Dickson, A. J. A molybdenum-isotope perspective on Phanerozoic deoxygenation events. Nat. Geosci. 10, 721–726 (2017).
Them, T. R. II et al. Thallium isotopes reveal protracted anoxia during the Toarcian (Early Jurassic) associated with volcanism, carbon burial, and mass extinction. Proc. Natl Acad. Sci. USA 115, 6596–6601 (2018).
Jenkyns, H. C. The Early Toarcian (Jurassic) anoxic event: stratigraphic, sedimentary, and geochemical evidence. Am. J. Sci. 288, 101–151 (1988).
Kemp, D. B., Coe, A. L., Cohen, A. S. & Schwark, L. Astronomical pacing of methane release in the Early Jurassic period. Nature 437, 396–399 (2005).
Boulila, S. et al. Astronomical calibration of the Toarcian Stage: implications for sequence stratigraphy and duration of the early Toarcian OAE. Earth Planet. Sci. Lett. 386, 98–111 (2014).
Sell, B. et al. Evaluating the temporal link between Karoo LIP and climatic–biologic events of the Toarcian stage with high-precision U–Pb geochronology. Earth Planet. Sci. Lett. 408, 48–56 (2014).
Duncan, R. A., Hooper, P. R., Rehacek, J., Marsh, J. S. & Duncan, A. R. The timing and duration of the Karoo igneous event, southern Gondwana. J. Geophys. Res. 102, 18127–18138 (1997).
Hesselbo, S. P. et al. Massive dissociation of gas hydrate during a Jurassic oceanic anoxic event. Nature 406, 392–395 (2000).
Pálfy, J. & Smith, P. L. Synchrony between Early Jurassic extinction, oceanic anoxic event, and the Karoo-Ferrar flood basalt volcanism. Geology 28, 747–750 (2000).
Beerling, D. J. & Brentnall, S. J. Numerical evaluation of mechanisms driving Early Jurassic changes in global carbon cycling. Geology 35, 247–250 (2007).
Svensen, H. et al. Hydrothermal venting of greenhouse gases triggering Early Jurassic global warming. Earth Planet. Sci. Lett. 256, 554–566 (2007).
Hesselbo, S. P. & Pieńkowski, G. Stepwise atmospheric carbon-isotope excursion during the Toarcian Oceanic Anoxic Event (Early Jurassic, Polish Basin). Earth Planet. Sci. Lett. 301, 365–372 (2011).
Svensen, H., Corfu, F., Polteau, S., Hammer, Ø. & Planke, S. Rapid magma emplacement in the Karoo Large Igneous Province. Earth Planet. Sci. Lett. 325–326, 1–9 (2012).
Ivanov, A. V. et al. Timing and genesis of the Karoo-Ferrar large igneous province: new high precision U–Pb data for Tasmania confirm short duration of the major magmatic pulse. Chem. Geol. 455, 32–43 (2017).
Palliani, R. B. & Riding, J. B. A palynological investigation of the Lower and lowermost Middle Jurassic strata (Sinemurian to Aalenian) from North Yorkshire, UK. Proc. Yorks. Geol. Soc. 53, 1–16 (2000).
Palliani, R. B., Mattioli, E. & Riding, J. B. The response of marine phytoplankton and sedimentary organic matter to the early Toarcian (Lower Jurassic) oceanic anoxic event in northern England. Mar. Micropaleontol. 46, 223–245 (2002).
Danise, S., Twitchett, R. J. & Little, C. T. S. Environmental controls on Jurassic marine ecosystems during global warming. Geology 43, 263–266 (2015).
Danise, S., Twitchett, R. J., Little, C. T. S. & Clémence, M. E. The impact of global warming and anoxia on marine benthic community dynamics: an example from the Toarcian (Early Jurassic). PLoS ONE 8, e56255 (2013).
Ullmann, C. V., Thibault, N., Ruhl, M., Hesselbo, S. P. & Korte, C. Effect of a Jurassic oceanic anoxic event on belemnite ecology and evolution. Proc. Natl Acad. Sci. USA 111, 10073–10076 (2014).
Balme, B. E. Fossil in situ spores and pollen grains: an annotated catalogue. Rev. Palaeobot. Palynol. 87, 81–323 (1995).
Vakhrameev, V. A. Jurassic and Cretaceous Floras and Climates of the Earth (Cambridge Univ. Press, 1991).
Pieńkowski, G., Hodbod, M. & Ullmann, C. V. Fungal decomposition of terrestrial organic matter accelerated Early Jurassic climate warming. Sci. Rep. 6, 31930 (2016).
Batten, D. J. & Dutta, R. J. Ultrastructure of exine of gymnospermous pollen grains from Jurassic and basal Cretaceous deposits in Northwest Europe and implications for botanical relationships. Rev. Palaeobot. Palynol. 99, 25–54 (1997).
Dejax, J., Pons, D. & Yans, J. Palynology of the dinosaur-bearing Wealden facies in the natural pit of Bernissart (Belgium). Rev. Palaeobot. Palynol. 144, 25–38 (2007).
Koppelhus, E. B. & Dam, G. Palynostratigraphy and palaeoenvironments of the Rævekløft, Gule Horn and Ostreaelv Formations (Lower–Middle Jurassic), Neill Klinter Group, Jameson Land, East Greenland. Geol. Surv. Den. Greenl. Bull. 1, 723–775 (2003).
Belcher, C. M. et al. Increased fire activity at the Triassic/Jurassic boundary in Greenland due to climate-driven floral change. Nat. Geosci. 3, 426–429 (2010).
Stukins, S., Jolley, D. W., McIlroy, D. & Hartley, A. J. Middle Jurassic vegetation dynamics from allochthonous palynological assemblages: an example from a marginal marine depositional setting; Lajas Formation, Neuquén Basin, Argentina. Palaeogeogr. Palaeoclimatol. Palaeoecol. 392, 117–127 (2013).
Xu, W. et al. Carbon sequestration in an expanded lake system during the Toarcian oceanic anoxic event. Nat. Geosci. 10, 129–134 (2017).
Wignall, P. B., Newton, R. J. & Little, C. T. S. The timing of paleoenvironmental change and cause-and-effect relationships during the Early Jurassic mass extinction in Europe. Am. J. Sci. 305, 1014–1032 (2005).
Thibault, N. et al. The wider context of the Lower Jurassic Toarcian oceanic anoxic event in Yorkshire coastal outcrops, UK. Proc. Geol. Assoc. 129, 372–391 (2018).
Izumi, K., Endo, K., Kemp, D. B. & Inui, M. Oceanic redox conditions through the late Pliensbachian to early Toarcian on the northwestern Panthalassa margin: insights from pyrite and geochemical data. Palaeogeogr. Palaeoclimatol. Palaeoecol. 492, 1–10 (2018).
Dera, G. & Donnadieu, Y. Modelling evidences for global warming, Arctic seawater freshening, and sluggish oceanic circulation during the Early Toarcian anoxic event. Paleoceanography 27, PA2211 (2012).
McArthur, J. M., Donovan, D. T., Thirlwall, M. F., Fouke, B. W. & Mattey, D. Strontium isotope profile of the early Toarcian (Jurassic) Oceanic Anoxic Event, the duration of ammonite biozones, and belemnite paleotemperatures. Earth Planet. Sci. Lett. 179, 269–285 (2000).
Cohen, A. S., Coe, A. L., Harding, S. M. & Schwark, L. Osmium isotope evidence for the regulation of atmospheric CO2 by continental weathering. Geology 32, 157–160 (2004).
Percival, L. M. E. et al. Osmium isotope evidence for two pulses of increased continental weathering linked to Early Jurassic volcanism and climate change. Geology 44, 759–762 (2016).
Them, T. R. et al. Evidence for rapid weathering response to climatic warming during the Toarcian Oceanic Anoxic Event. Sci. Rep. 7, 5003 (2017).
Xu, W. et al. Evolution of the Toarcian (Early Jurassic) carbon-cycle and global climatic controls on local sedimentary processes (Cardigan Bay Basin, UK). Earth Planet. Sci. Lett. 484, 396–411 (2018).
Baker, S. J., Hesselbo, S. P., Lenton, T. M., Duarte, L. V. & Belcher, C. M. Charcoal evidence that rising atmospheric oxygen terminated Early Jurassic ocean anoxia. Nat. Commun. 8, 15018 (2017).
Loope, D. B., Rowe, C. M. & Joeckel, R. M. Annual monsoon rains recorded by Jurassic dunes. Nature 412, 64–66 (2001).
Slater, S. M. & Wellman, C. H. Middle Jurassic vegetation dynamics based on quantitative analysis of spore/pollen assemblages from the Ravenscar Group, North Yorkshire, UK. Palaeontology 59, 305–328 (2016).
Moulin, M. et al. Eruptive history of the Karoo lava flows and their impact on early Jurassic environmental change. J. Geophys. Res. Solid Earth 122, 738–772 (2017).
Xu, W. et al. Magnetostratigraphy of the Toarcian Stage (Lower Jurassic) or the Llandbedr (Mochras Farm) Borehole, Wales: basis for a global standard and implications for volcanic forcing of palaeoenvironmental change. J. Geol. Soc. 175, 594–604 (2018).
Burgess, S. D., Bowring, S. A., Fleming, T. H. & Elliot, D. H. High-precision geochronology links the Ferrar large igneous province with early-Jurassic ocean anoxia and biotic crisis. Earth Planet. Sci. Lett. 415, 90–99 (2015).
Fielding, C. R. et al. Age and pattern of the southern high-latitude continental end-Permian extinction constrained by multiproxy analysis. Nat. Commun. 10, 385 (2019).
Trenberth, K. E. et al. in Climate Change 2007: the Physical Science Basis (eds Solomon, S. et al.) Ch. 3 (Cambridge Univ. Press, 2007).
Macquaker, J. H. S., Keller, M. A. & Davies, S. J. Algal blooms and ‘marine snow’: mechanisms that enhance preservation of organic carbon in ancient fine-grained sediments. J. Sediment. Res. 80, 934–942 (2010).
Sephton, M. A. et al. Catastrophic soil erosion during the end-Permian biotic crisis. Geology 33, 941–944 (2005).
Alego, T. J., Chen, Z. Q., Fraiser, M. L. & Twitchett, R. J. Terrestrial–marine teleconnections in the collapse and rebuilding of Early Triassic marine ecosystems. Palaeogeogr. Palaeoclimatol. Palaeoecol. 308, 1–11 (2011).
Müller, J. et al. Cordilleran ice-sheet growth fueled primary productivity in the Gulf of Alaska, northeast Pacific Ocean. Geology 46, 307–310 (2018).
Diaz, R. J. & Rosenberg, R. Spreading dead zones and consequences for marine ecosystems. Science 321, 926–929 (2008).
Gedney, N. et al. Detection of a direct carbon dioxide effect in continental river runoff records. Nature 439, 835–838 (2006).
Steinthorsdottir, M., Woodward, F. I., Surlyk, F. & McElwain, J. C. Deep-time evidence of a link between elevated CO2 concentrations and perturbations in the hydrological cycle via drop in plant transpiration. Geology 40, 815–818 (2012).
Hesselbo, S. P., Jenkyns, H. C., Duarte, L. V. & Oliveira, L. C. V. Carbon-isotope record of the Early Jurassic (Toarcian) Oceanic Anoxic Event from fossil wood and marine carbonate (Lusitanian Basin, Portugal). Earth Planet. Sci. Lett. 253, 455–470 (2007).
Littler, K., Hesselbo, S. P. & Jenkyns, H. C. A carbon-isotope perturbation at the Pliensbachian–Toarcian boundary: evidence from the Lias Group, NE England. Geol. Mag. 147, 181–192 (2010).
Traverse, A. Paleopalynology 2nd edn (Springer, 2007).
Hammer, Ø., Harper, D. T. & Ryan, P. D. PAST: paleontological statistics software package for education and data analysis. Palaeontol. Electron. 4, 1–9 (2001).
We are grateful to W. Foster, D. Murphy and M.-E. Clemence for their help with fieldwork. We thank P. von Knorring for artwork in Fig. 4. This research was funded by the Wenner-Gren Foundation (grant no. UPD2017-0155), the Swedish Research Council (grant no. VR 2015-04264), Lund University Carbon Cycle Centre and a Natural Environment Research Council (NERC) grant to R.J.T. (grant no. NE/I005641/1).
The authors declare no competing interests.
Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary figures, tables and references
Raw palynological counts. ‘p’ refers to taxa that are present in slides but not in counts
Raw palynofacies counts
nMDS axis scores of samples for Fig. 3 and Supplementary Fig. 3.
About this article
Cite this article
Slater, S.M., Twitchett, R.J., Danise, S. et al. Substantial vegetation response to Early Jurassic global warming with impacts on oceanic anoxia. Nat. Geosci. 12, 462–467 (2019). https://doi.org/10.1038/s41561-019-0349-z
Palaeobiodiversity and Palaeoenvironments (2022)
International Journal of Earth Sciences (2022)
Nature Communications (2021)
Scientific Reports (2020)
Similarity analysis of Ostracoda faunas in the Western Tethys during the Late Pliensbachian-Early Toarcian (Early Jurassic)
Arabian Journal of Geosciences (2020)