Biometry and dissolution features of the benthic foraminiferal species Ammonia aomoriensis at high pCO2.

Haynert, Kristin, Schönfeld, Joachim, Riebesell, Ulf and Polovodova, Irina (2011) Biometry and dissolution features of the benthic foraminiferal species Ammonia aomoriensis at high pCO2. Open Access Marine Ecology Progress Series, 432 . pp. 53-67. DOI 10.3354/meps09138.

[img]
Preview
Text
Haynert_al_2011.pdf - Published Version

Download (1061Kb)

Supplementary data:

Abstract

Culturing experiments were performed with the benthic foraminifer Ammonia aomoriensis from Flensburg Fjord, western Baltic Sea. The experiments simulated a projected rise in atmospheric CO2 concentrations. We exposed specimens to 5 seawater pCO2 levels ranging from 618 µatm (pH 7.9) to 3130 µatm (pH 7.2) for 6 wk. Growth rates and mortality differed significantly among pCO2 treatments. The highest increase of mean test diameter (19%) was observed at 618 µatm. At partial pressures >1829 µatm, the mean test diameter was observed to decrease, by up to 22% at 3130 µatm. At pCO2 levels of 618 and 751 µatm, A. aomoriensis tests were found intact after the experiment. The outer chambers of specimens incubated at 929 and 1829 µatm were severely damaged by corrosion. Visual inspection of specimens incubated at 3130 µatm revealed wall dissolution of all outer chambers, only their inner organic lining stayed intact. Our results demonstrate that pCO2 values of ≥929 µatm in Baltic Sea waters cause reduced growth of A. aomoriensis and lead to shell dissolution. The bottom waters in Flensburg Fjord and adjacent areas regularly experience pCO2 levels in this range during summer and fall. Increasing atmospheric CO2 concentrations are likely to extend and intensify these periods of undersaturation. This may eventually slow down calcification in A. aomoriensis to the extent that net carbonate precipitation terminates. The possible disappearance of this species from the Baltic Sea and other areas prone to seasonal undersaturation would likely cause significant shifts in shallow-water benthic ecosystems in the near future.

Document Type: Article
Keywords: Biogeochemistry; Benthic foraminifera ; Biometry ; Test dissolution ; Carbon dioxide ; Baltic Sea
Research affiliation: OceanRep > The Future Ocean - Cluster of Excellence
OceanRep > GEOMAR > FB2 Marine Biogeochemistry > FB2-BI Biological Oceanography
OceanRep > GEOMAR > FB1 Ocean Circulation and Climate Dynamics > FB1-P-OZ Paleo-Oceanography
Refereed: Yes
Open Access Journal?: No
DOI etc.: 10.3354/meps09138
ISSN: 0171-8630
Projects: Future Ocean
Date Deposited: 05 Jul 2011 10:13
Last Modified: 22 Jun 2018 10:04
URI: http://oceanrep.geomar.de/id/eprint/11967

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...