Summary
Sinking organic matter transports carbon from surface waters to the deep ocean.
In depth
Phytoplankton fix carbon; some sinks as dead cells, faecal pellets and marine snow, exporting about 10 Gt carbon per year to depth, where it can be locked away for centuries. Without it atmospheric CO2 would be far higher.
The pump's efficiency depends on plankton community and temperature. Warming may reduce export. Biological carbon stored in sediments can last millions of years.
Key idea: marine life moves carbon from air to depth.
The biological pump transfers carbon from the atmosphere and surface to the deep ocean through biology. Phytoplankton fix CO2 by photosynthesis; when they die, are eaten, or produce faecal pellets, organic particles (marine snow) sink out of the surface layer.
Most is respired and recycled in the upper ocean, but about 1 to 10 percent reaches the deep sea, where it can be stored for centuries or buried in sediments. Zooplankton migrating daily add active transport, and ballast minerals such as calcite speed sinking. Without the pump, atmospheric CO2 would be around 200 ppm higher.
Example: iron fertilisation experiments test whether adding iron can increase the pump.
Frequently asked questions
What is Biological Pump?
Sinking organic matter transports carbon from surface waters to the deep ocean.
Which area of biology covers Biological Pump, and how advanced is it?
Biological Pump is one of the 54 topics in Marine & Environmental Biology. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Marine Food Webs, Upwelling, Permafrost and Methane.
Why does Biological Pump matter?
It regulates climate on long timescales.
Can you give an example of Biological Pump?
Iron fertilisation experiments test boosting the pump.
What should I learn before Biological Pump?
Work through the Beginner topics in Marine & Environmental Biology first, such as Oceans, Ocean Zones, Plankton, then return to Biological Pump. Advanced topics assume the Intermediate vocabulary.
What topics are related to Biological Pump?
The closest topics to Biological Pump are Marine Food Webs, Upwelling, Permafrost and Methane, Oceans. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Biological Pump?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Biological Pump. To practise the whole of Marine & Environmental Biology, use the Marine & Environmental Biology quiz.
How is Biological Pump different from Marine Food Webs?
Biological Pump: Sinking organic matter transports carbon from surface waters to the deep ocean. Marine Food Webs: Phytoplankton support zooplankton, fish and top predators, with energy lost at each level. Read both side by side and note what each one explains.
How should I study Biological Pump step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Marine Food Webs and explain the difference aloud. Finally, take the Marine & Environmental Biology quiz and come back to this page for any question you miss.