Preview

PDF 1Mb

The physiological performance of two coccolithophore species, Emiliania huxleyi and Coccolithus braarudii, was investigated during long-term exposure to elevated pCO2 levels. Mono-specific cultures were grown over 152 (E. huxleyi) and 65 (C. braarudii) generations while pCO2 was gradually increased to maximum levels of 1150 ìatm (E. huxleyi) and 930 ìatm (C. braarudii) and kept constant thereafter. Rates of cell growth and cell quotas of particulate organic carbon (POC), particulate inorganic carbon (PIC) and total particulate nitrogen (TPN) were determined repeatedly throughout the incubation period. Increasing pCO2 caused a decrease in cell growth rate of 9% and 29% in E. huxleyi and C. braarudii, respectively. In both species cellular PIC:TPN and PIC:POC ratios decreased in response to rising pCO2, whereas no change was observed in the POC:TPN ratios of E. huxleyi and C. braarudii. These results are consistent with those obtained in shorter-term high CO2 exposure experiments following abrupt pertubations of the seawater carbonate system and indicate that for the strains tested here a gradual CO2 increase does not alleviate CO2/pH sensitivity.

Item Type:	Refereed Article
Research Division:	Earth Sciences
Research Group:	Oceanography
Research Field:	Biological oceanography
Objective Division:	Environmental Policy, Climate Change and Natural Hazards
Objective Group:	Understanding climate change
Objective Field:	Effects of climate change on the South Pacific (excl. Australia and New Zealand) (excl. social impacts)
UTAS Author:	Muller, MN (Dr Marius Muller)
ID Code:	72198
Year Published:	2010
Web of Science® Times Cited:	62
Deposited By:	IMAS Research and Education Centre
Deposited On:	2011-08-23
Last Modified:	2012-03-06
Downloads:	401 View Download Statistics