Editing Phytoplankton (section)

==Diversity==
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| image1            = Spring Bloom Colors the Pacific Near Hokkaido.jpg
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| caption1          = When two currents collide (here the [[Oyashio Current|Oyashio]] and [[Kuroshio Current|Kuroshio]] currents) they create [[eddies]]. Phytoplankton concentrates along the boundaries of the eddies, tracing the motion of the water.
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| caption2          = [[Algal bloom]] off south west England
| image3            = NASA satellite view of Southern Ocean phytoplankton bloom (crop).jpg
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| caption3          = NASA satellite view of Southern Ocean phytoplankton bloom
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The term phytoplankton encompasses all photoautotrophic microorganisms in aquatic [[food web]]s. However, unlike terrestrial [[communities]], where most autotrophs are [[plant]]s, phytoplankton are a diverse group, incorporating [[protist]]an [[eukaryote]]s and both [[Bacteria|eubacterial]] and [[archaebacteria]]l [[prokaryote]]s. There are about 5,000 known species of marine phytoplankton.<ref name="Hallegraeff 03">{{cite book|title=Manual on Harmful Marine Microalgae|last=Hallegraeff|first=G.M.|publisher=Unesco|year=2003|isbn=978-92-3-103871-6|editor-last1=Hallegraeff|editor-first1=Gustaaf M.|pages=25–49|chapter=Harmful algal blooms: a global overview|editor-last2=Anderson|editor-first2=Donald Mark|editor-last3=Cembella|editor-first3=Allan D.|editor-last4=Enevoldsen|editor-first4=Henrik O.|chapter-url=http://unesdoc.unesco.org/images/0013/001317/131711e.pdf}}</ref> How such diversity [[evolution|evolved]] despite scarce resources (restricting [[niche differentiation]]) is unclear.<ref>{{cite journal|last1=Hutchinson|first1=G. E.|year=1961|title=The Paradox of the Plankton|journal=The American Naturalist|volume=95|issue=882|pages=137–45|doi=10.1086/282171|s2cid=86353285}}</ref>

In terms of numbers, the most important groups of phytoplankton include the [[diatom]]s, [[cyanobacteria]] and [[dinoflagellate]]s, although many other groups of [[algae]] are represented. One group, the [[coccolithophore|coccolithophorids]], is responsible (in part) for the release of significant amounts of [[dimethyl sulfide]] (DMS) into the [[Earth's atmosphere|atmosphere]]. DMS is [[Redox|oxidized]] to form sulfate which, in areas where ambient [[aerosol]] particle concentrations are low, can contribute to the population of [[cloud condensation nuclei]], mostly leading to increased cloud cover and cloud [[albedo]] according to the so-called [[CLAW hypothesis]].<ref name="Oceanicphytoplankton">{{cite journal|last1=Charlson|first1=Robert J.|last2=Lovelock|first2=James E.|last3=Andreae|first3=Meinrat O.|last4=Warren|first4=Stephen G.|year=1987|title=Oceanic phytoplankton, atmospheric sulphur, cloud albedo and climate|journal=Nature|volume=326|issue=6114|pages=655–61|bibcode=1987Natur.326..655C|doi=10.1038/326655a0|s2cid=4321239}}</ref><ref>{{cite journal|last1=Quinn|first1=P. K.|author-link1=Patricia Quinn (scientist)|last2=Bates|first2=T. S.|year=2011|title=The case against climate regulation via oceanic phytoplankton sulphur emissions|journal=Nature|volume=480|issue=7375|pages=51–6|bibcode=2011Natur.480...51Q|doi=10.1038/nature10580|pmid=22129724|s2cid=4417436|url=https://zenodo.org/record/1233319}}</ref> Different types of phytoplankton support different [[trophic level]]s within varying ecosystems. In [[oligotroph]]ic oceanic regions such as the [[Sargasso Sea]] or the [[South Pacific Gyre]], phytoplankton is dominated by the small sized cells, called [[Photosynthetic picoplankton|picoplankton]] and nanoplankton (also referred to as picoflagellates and nanoflagellates), mostly composed of [[cyanobacteria]] (''[[Prochlorococcus]]'', ''[[Synechococcus]]'') and picoeucaryotes such as ''[[Micromonas]]''. Within more productive ecosystems, dominated by [[upwelling]] or high terrestrial inputs, larger [[dinoflagellate]]s are the more dominant phytoplankton and reflect a larger portion of the [[Biomass (ecology)|biomass]].<ref>{{cite journal|last1=Calbet|first1=A.|year=2008|title=The trophic roles of microzooplankton in marine systems|journal=ICES Journal of Marine Science|volume=65|issue=3|pages=325–31|doi=10.1093/icesjms/fsn013|doi-access=free}}</ref>