Open AccessThis article is
- freely available
Ocean Acidification and the End-Permian Mass Extinction: To What Extent does Evidence Support Hypothesis?
Institute for the Environment, Halsbury Building, Brunel University, Uxbridge UB8 3PH, UK
CNRS-UMR7207, CR2P ‘Centre de Recherche sur la Paléobiodiversité et les Paléoenvironnements’, Université Pierre et Marie Curie-Paris 6, Paris 75252 Cedex 05 , France
Nanjing Institute of Geology and Palaeontology, Nanjing 210008, China
UMR5561 Biogéosciences, Bâtiment Gabriel, Université de Bourgogne, Dijon 21000, France
* Author to whom correspondence should be addressed.
Received: 21 July 2012; in revised form: 16 August 2012 / Accepted: 18 September 2012 / Published: 28 September 2012
Abstract: Ocean acidification in modern oceans is linked to rapid increase in atmospheric CO2, raising concern about marine diversity, food security and ecosystem services. Proxy evidence for acidification during past crises may help predict future change, but three issues limit confidence of comparisons between modern and ancient ocean acidification, illustrated from the end-Permian extinction, 252 million years ago: (1) problems with evidence for ocean acidification preserved in sedimentary rocks, where proposed marine dissolution surfaces may be subaerial. Sedimentary evidence that the extinction was partly due to ocean acidification is therefore inconclusive; (2) Fossils of marine animals potentially affected by ocean acidification are imperfect records of past conditions; selective extinction of hypercalcifying organisms is uncertain evidence for acidification; (3) The current high rates of acidification may not reflect past rates, which cannot be measured directly, and whose temporal resolution decreases in older rocks. Thus large increases in CO2 in the past may have occurred over a long enough time to have allowed assimilation into the oceans, and acidification may not have stressed ocean biota to the present extent. Although we acknowledge the very likely occurrence of past ocean acidification, obtaining support presents a continuing challenge for the Earth science community.
Keywords: ocean acidification; end-Permian extinction; microbialite; ocean buffer; stylolite
Citations to this Article
Cite This Article
MDPI and ACS Style
Kershaw, S.; Crasquin, S.; Li, Y.; Collin, P.-Y.; Forel, M.-B. Ocean Acidification and the End-Permian Mass Extinction: To What Extent does Evidence Support Hypothesis? Geosciences 2012, 2, 221-234.
Kershaw S, Crasquin S, Li Y, Collin P-Y, Forel M-B. Ocean Acidification and the End-Permian Mass Extinction: To What Extent does Evidence Support Hypothesis? Geosciences. 2012; 2(4):221-234.
Kershaw, Stephen; Crasquin, Sylvie; Li, Yue; Collin, Pierre-Yves; Forel, Marie-Béatrice. 2012. "Ocean Acidification and the End-Permian Mass Extinction: To What Extent does Evidence Support Hypothesis?" Geosciences 2, no. 4: 221-234.