Effect of CO 2 concentration on C : N : P ratio in marine phytoplankton: A species comparison

  • Burkhardt S
  • Zondervan I
  • Riebesell U
  • 3

    Readers

    Mendeley users who have this article in their library.
  • N/A

    Citations

    Citations of this article.

Abstract

The effect of variable concentrations of dissolved molecular carbon dioxide, [CO2,aq], on C:N:P ratios in marine phytoplankton was studied in batch cultures under high light, nutrient-replete conditions at different irradiance cycles. The elemental composition in six out of seven species tested was affected by variation in [CO2,aq]. Among these species, the magnitude of change in C:N:P was similar over the experimental CO2 range. Differences in both cell size and day length- dependent growth rate had little effect on the critical CO2 concentration below which a further decrease in [CO2,aq] led to large changes in C:N:P ratios. Significant CO2-related changes in elemental ratios were observed at [CO2,aq] < 10 mu mol kg-l and correlated with a CO2-dependent decrease in growth rate. At [CO2,aq] typical for ocean surface waters, variation in C:N:P was relatively small under our experimental conditions. No general pattern far CO2-related changes in the elemental composition could be found with regard to the direction of trends. Either an increase or a decrease in C:N and C:P with increasing [CO2,aq] was observed, depending on the species tested. Diurnal variation in C:N and C:P, tested in Skeletonema costatum, was of a similar magnitude as CO2-related variation. In this species, the CO2 effect was superimposed on diurnal variation, indicating that differences in elemental ratios at the end of the photoperiod were not caused by a transient buildup of carbon-rich storage compounds due to a more rapid accumulation of carbohydrates at high CO2 concentrations. If our results obtained under high light, nutrient-replete conditions are representative for natural phytoplankton populations, CO2-related changes in plankton stoichiometry are unlikely to have a significant effect on the oceanic carbon cycle

Author-supplied keywords

  • CO2
  • CO2 CONCENTRATION
  • Carbohydrates
  • Carbon
  • Carbon cycle
  • Diurnal
  • MARINE
  • MARINE-PHYTOPLANKTON
  • Ocean
  • Phytoplankton
  • Stoichiometry
  • Surface waters
  • Variation
  • carbon dioxide
  • elemental composition
  • growth
  • plankton
  • water

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

There are no full text links

Authors

  • S Burkhardt

  • I Zondervan

  • U Riebesell

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free