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| Titel |
Projected impacts of climate change and ocean acidification on the global biogeography of planktonic Foraminifera |
| VerfasserIn |
T. Roy, F. Lombard, L. Bopp, M. Gehlen |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1726-4170
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| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 12, no. 10 ; Nr. 12, no. 10 (2015-05-19), S.2873-2889 |
| Datensatznummer |
250117936
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| Publikation (Nr.) |
 copernicus.org/bg-12-2873-2015.pdf |
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| Zusammenfassung |
| Planktonic Foraminifera are a major contributor to the deep carbonate flux
and their microfossil deposits form one of the richest databases for
reconstructing paleoenvironments, particularly through changes in their
taxonomic and shell composition. Using an empirically based planktonic
foraminifer model that incorporates three known major physiological drivers
of their biogeography – temperature, food and light – we investigate (i)
the global redistribution of planktonic Foraminifera under anthropogenic
climate change and (ii) the alteration of the carbonate chemistry of
foraminiferal habitat with ocean acidification. The present-day and future
(2090–2100) 3-D distributions of Foraminifera are simulated using
temperature, plankton biomass and light from an Earth system model forced
with a historical and a future (IPCC A2) high CO2 emission scenario.
Foraminiferal abundance and diversity are projected to decrease in the
tropics and subpolar regions and increase in the subtropics and around the
poles. Temperature is the dominant control on the future change in the
biogeography of Foraminifera. Yet food availability acts to either reinforce
or counteract the temperature-driven changes. In the tropics and subtropics the
largely temperature-driven shift to depth is enhanced by the increased
concentration of phytoplankton at depth. In the higher latitudes the
food-driven response partly offsets the temperature-driven reduction both in
the subsurface and across large geographical regions. The large-scale
rearrangements in foraminiferal abundance and the reduction in the carbonate
ion concentrations in the habitat range of planktonic foraminifers – from
10–30 μmol kg−1 in their polar and subpolar habitats to
30–70 μmol kg−1 in their subtropical and tropical habitats –
would be expected to lead to changes in the marine carbonate flux.
High-latitude species are most vulnerable to anthropogenic change: their
abundance and available habitat decrease and up to 10% of the volume of
their habitat drops below the calcite saturation horizon. |
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