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Ecological response to collapse of the biological pump following the mass extinction at the Cretaceous Paleogene boundary
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Date
2016-01-01
Author
Vellekoop, Johan
Woelders, Lineke
Açıkalın, Sanem
Smit, Jan
van de Schootbrugge, Bas
Yılmaz, İsmail Ömer
Brinkhuis, Henk
Speijer, Robert P
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. It is by now unequivocally shown that the mass extinction associated with the Cretaceous-Paleogene (K-Pg) boundary (~66 Ma) is related to the environmental effects of a large extraterrestrial impact. The biological and oceanographic consequences of the mass extinction are, however, still poorly understood. According to the Living Ocean model of D’Hondt et al. (1998), the biological crisis at the K-Pg boundary resulted in a reduction of export productivity in 20 the earliest Paleocene. Here, we combine organic-walled dinoflagellate cyst (dinocyst) and benthic foraminiferal analyses to provide crucial new insight into changes in the coupling of pelagic and benthic ecosystems. To this end, we perform dinocyst and benthic foraminiferal analyses on the recently discovered Tethyan K-Pg boundary section at Okçular, Northwestern Turkey, and compare the results with other K-Pg boundary sites in the Tethys. The post-impact dominance of epibenthic taxa and an increase of inferred heterotrophic dinocysts in the earliest Paleocene at Okçular are consistent with published records 25 from other Tethyan sites. Together, these Tethyan records indicate that during the early Paleocene more nutrients were available for the Tethyan planktonic community, whereas benthic communities were deprived of food. Hence, the postimpact phase the reduction of export productivity likely resulted in enhanced recycling of nutrients in the upper part of the water column, all along the Tethyan shelves.
URI
https://hdl.handle.net/11511/41539
Journal
Biogeosciences Discussions
DOI
https://doi.org/10.5194/bg-2016-275
Collections
Department of Geological Engineering, Article
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J. Vellekoop et al., “Ecological response to collapse of the biological pump following the mass extinction at the Cretaceous Paleogene boundary,”
Biogeosciences Discussions
, pp. 1–27, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41539.