Advanced

Experimental evidence for foraminiferal calcification under anoxia

Nardelli, M. P.; Barras, C.; Metzger, E.; Mouret, A.; Filipsson, Helena LU ; Jorissen, F. and Geslin, E. (2014) In Biogeosciences 11(14). p.4029-4038
Abstract
Benthic foraminiferal tests are widely used for paleoceanographic reconstructions from a range of different environments with varying dissolved oxygen concentrations in the bottom water. There is ample evidence that foraminifera can live in anoxic sediments. For some species, this is explained by a switch to facultative anaerobic metabolism (i.e. denitrification). Here we show for the first time that adult specimens of three benthic foraminiferal species are not only able to survive, but are also able to calcify under anoxic conditions, at various depths in the sediment, and with or without nitrates. In fact, several specimens of Ammonia tepida (1-4 %), Bulimina marginata (8-24 %) and Cassidulina laevigata (16-23 %) were able to calcify at... (More)
Benthic foraminiferal tests are widely used for paleoceanographic reconstructions from a range of different environments with varying dissolved oxygen concentrations in the bottom water. There is ample evidence that foraminifera can live in anoxic sediments. For some species, this is explained by a switch to facultative anaerobic metabolism (i.e. denitrification). Here we show for the first time that adult specimens of three benthic foraminiferal species are not only able to survive, but are also able to calcify under anoxic conditions, at various depths in the sediment, and with or without nitrates. In fact, several specimens of Ammonia tepida (1-4 %), Bulimina marginata (8-24 %) and Cassidulina laevigata (16-23 %) were able to calcify at different redox fronts of sediment cores, under laboratory conditions. This demonstrates ongoing metabolic processes, even in microenvironments where denitrification is not possible. Earlier observations suggest that the disappearance of foraminiferal communities after prolonged anoxia is not due to instantaneous or strongly increased adult mortality. Here we show that it cannot be explained by an inhibition of growth through chamber addition either. Our observations of ongoing calcification under anoxic conditions mean that geochemical proxy data obtained from benthic foraminifera in settings experiencing intermittent anoxia have to be reconsidered. The analysis of whole single specimens or of their successive chambers may provide essential information about short-term environmental variability and/or the causes of anoxia. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Biogeosciences
volume
11
issue
14
pages
4029 - 4038
publisher
Copernicus Publications
external identifiers
  • wos:000339895600020
  • scopus:84905492802
ISSN
1726-4189
DOI
10.5194/bg-11-4029-2014
project
BECC
language
English
LU publication?
yes
id
c3fdccb0-d797-4159-8e60-d0735f2a0f59 (old id 4668150)
date added to LUP
2014-09-24 14:45:19
date last changed
2017-10-29 03:15:08
@article{c3fdccb0-d797-4159-8e60-d0735f2a0f59,
  abstract     = {Benthic foraminiferal tests are widely used for paleoceanographic reconstructions from a range of different environments with varying dissolved oxygen concentrations in the bottom water. There is ample evidence that foraminifera can live in anoxic sediments. For some species, this is explained by a switch to facultative anaerobic metabolism (i.e. denitrification). Here we show for the first time that adult specimens of three benthic foraminiferal species are not only able to survive, but are also able to calcify under anoxic conditions, at various depths in the sediment, and with or without nitrates. In fact, several specimens of Ammonia tepida (1-4 %), Bulimina marginata (8-24 %) and Cassidulina laevigata (16-23 %) were able to calcify at different redox fronts of sediment cores, under laboratory conditions. This demonstrates ongoing metabolic processes, even in microenvironments where denitrification is not possible. Earlier observations suggest that the disappearance of foraminiferal communities after prolonged anoxia is not due to instantaneous or strongly increased adult mortality. Here we show that it cannot be explained by an inhibition of growth through chamber addition either. Our observations of ongoing calcification under anoxic conditions mean that geochemical proxy data obtained from benthic foraminifera in settings experiencing intermittent anoxia have to be reconsidered. The analysis of whole single specimens or of their successive chambers may provide essential information about short-term environmental variability and/or the causes of anoxia.},
  author       = {Nardelli, M. P. and Barras, C. and Metzger, E. and Mouret, A. and Filipsson, Helena and Jorissen, F. and Geslin, E.},
  issn         = {1726-4189},
  language     = {eng},
  number       = {14},
  pages        = {4029--4038},
  publisher    = {Copernicus Publications},
  series       = {Biogeosciences},
  title        = {Experimental evidence for foraminiferal calcification under anoxia},
  url          = {http://dx.doi.org/10.5194/bg-11-4029-2014},
  volume       = {11},
  year         = {2014},
}