Is Half of the World’s Oxygen Produced via Marine Phytoplankton?

Check out this answer from Consensus:

The research collectively supports the assertion that marine phytoplankton contribute to approximately half of the world’s oxygen production. However, this contribution is subject to variability due to environmental factors such as climate change and seasonal changes. The decline in phytoplankton populations poses a significant risk to global oxygen levels, highlighting the need for further research and conservation efforts.

Marine phytoplankton are microscopic organisms that play a crucial role in the Earth’s oxygen production through photosynthesis. There is a common assertion that half of the world’s oxygen is produced by these marine organisms. This synthesis aims to analyze the validity of this claim based on multiple research papers.

Key Insights

• Significant Contribution to Oxygen Production:
  • Multiple studies estimate that marine phytoplankton are responsible for producing approximately half of the world’s oxygen through photosynthesis1 2 5 6 7.
• Impact of Climate Change:
  • The rate of oxygen production by phytoplankton is influenced by water temperature, which can be affected by global warming. Rising temperatures may lead to decreased oxygen production and potential ecological disasters1 4 7.
• Decline in Phytoplankton Populations:
  • There is evidence suggesting a decline in phytoplankton populations, with some studies indicating a decrease of about 1% per year since 1900. This decline could significantly impact global oxygen levels4 8.
• Variability in Oxygen Production:
  • The relationship between carbon-based and oxygen-based primary productivity can vary seasonally and regionally, indicating that oxygen production by phytoplankton is not constant and can fluctuate3 6 10.

Is half of the world’s oxygen produced via marine phytoplankton?

Federico Lauro has answered Near Certain

An expert from Nanyang Technological University in Genomics, Microbiology, Oceanography

Estimates of modern contribution to primary production are in this paper: http://science.sciencemag.org/content/281/5374/237.full

Going back in time to ~2.5 billion years ago, because unicellular microbes (i.e. phytoplankton) were the first organisms to ever produce oxygen and without them all life as we know it would not exist, one could say that all oxygen on the planet is a result of phytoplankton activity.

Is half of the world’s oxygen produced via marine phytoplankton?

Paul Falkowski has answered Likely

An expert from Rutgers University in Marine Biology, Oceanography

Yes – about 45% of the carbon fixed on Earth is by marine phytoplankton – that would correspond to about 45% of the world’s oxygen. Here is the original paper:

http://science.sciencemag.org/content/281/5374/237