Editing Plankton (section)

===Oxygen production===
{{see also|oxygen cycle}}

[[Phytoplankton]] absorb energy from the Sun and nutrients from the water to produce their own nourishment or energy. In the process of [[photosynthesis]], phytoplankton release molecular [[oxygen]] ({{chem|O|2}}) into the water as a waste byproduct. It is estimated that about 50% of the world's oxygen is produced via phytoplankton photosynthesis.<ref name="NalGeo">{{cite news |last=Roach |first=John |url= http://news.nationalgeographic.com/news/2004/06/0607_040607_phytoplankton.html |archive-url= https://web.archive.org/web/20040608065449/http://news.nationalgeographic.com/news/2004/06/0607_040607_phytoplankton.html |url-status= dead |archive-date= June 8, 2004 |title=Source of Half Earth's Oxygen Gets Little Credit |work=National Geographic News |date=June 7, 2004 |access-date=2016-04-04 }}</ref> The rest is produced via photosynthesis on land by [[plant]]s.<ref name="NalGeo"/> Furthermore, phytoplankton photosynthesis has controlled the atmospheric [[Carbon dioxide in Earth's atmosphere|{{chem|C|O|2}}]]/[[Oxygen#Build-up in the atmosphere|{{chem|O|2}}]] balance since the early [[Precambrian]] Eon.<ref name="Tappan">{{cite journal |title=Primary production, isotopes, extinctions and the atmosphere |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |date=April 1968 |last=Tappan |first=Helen |volume=4 |issue=3 |pages=187–210 |doi=10.1016/0031-0182(68)90047-3 |bibcode= 1968PPP.....4..187T }}</ref>