Cyanobacterial buoyancy regulation: The paradoxical roles of carbon

Andrew R. Kleiner, John J. Cullen, Michael T Mageau, Kathryn M. Hanson, Richard A. Sundell

Research output: Contribution to journalArticlepeer-review

55 Scopus citations


In stratified lakes, dominance of the phytoplankton by cyanobacteria is largely the result of their buoyancy and depth regulation. Bloom- forming cyanobacteria regulate the gas vesicle and storage polymer contents of their cells in response to interactive environmental factors, especially light and nutrients. While research on the roles of nitrogen and phosphorus in cyanobacterial buoyancy regulation has reached a consensus, evaluations of the roles of carbon have remained open to dispute. We investigated the various effects of changes in carbon availability on cyanobacterial buoyancy with continuous cultures of Microcystis aeruginosa Kuetz. emend. Elenkin (1924), a notorious bloom-former. Although CO2 limitation of photosynthesis can promote buoyancy in the short term by preventing the collapse of turgor- sensitive gas vesicles and/or by limiting polysaccharide accumulation, we found that sustained carbon limitation restricts buoyancy regulation by limiting gas vesicle as well as polysaccharide synthesis. These results provide an explanation for the positive effects of bicarbonate enrichment on cyanobacterial nitrogen uptake and bloom formation in lake experiments and may help to explain the pattern of cyanobacterial dominance in phosphorus- enriched, low-carbon lakes.

Original languageEnglish (US)
Pages (from-to)47-53
Number of pages7
JournalJournal of Phycology
Issue number1
StatePublished - Feb 1996


  • Cyanobacteria
  • Microcystis aeruginosa
  • blooms
  • cyanobacterial buoyancy
  • dominance
  • gas vacuolation
  • gas vesicles
  • lake eutrophication
  • limiting nutrients


Dive into the research topics of 'Cyanobacterial buoyancy regulation: The paradoxical roles of carbon'. Together they form a unique fingerprint.

Cite this