The Eocene Arctic Azolla bloom: environmental conditions, productivity and carbon drawdown

  title={The Eocene Arctic Azolla bloom: environmental conditions, productivity and carbon drawdown},
  author={Eveline N. Speelman and Monique M. L. van Kempen and Judith Barke and Henk Brinkhuis and Gert‐Jan Reichart and Alfons J. P. Smolders and Jan G. M. Roelofs and Francesca Sangiorgi and Johannes de Leeuw and Andr{\'e} F. Lotter and Jaap S. Sinninghe Damst{\'e}},
Enormous quantities of the free‐floating freshwater fern Azolla grew and reproduced in situ in the Arctic Ocean during the middle Eocene, as was demonstrated by microscopic analysis of microlaminated sediments recovered from the Lomonosov Ridge during Integrated Ocean Drilling Program (IODP) Expedition 302. The timing of the Azolla phase (~48.5 Ma) coincides with the earliest signs of onset of the transition from a greenhouse towards the modern icehouse Earth. The sustained growth of Azolla… 

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