Editing Coccolithophore (section)

===Global distribution===
[[File:Coccolithophore+Abundance.png|thumb|upright=1.7| Global distribution of coccolithophores in the ocean]]

Coccolithophores occur throughout the world's oceans. Their distribution varies vertically by stratified layers in the ocean and geographically by different temporal zones.<ref name=Geisen2004>{{cite book |last1=Geisen |first1=M. |editor1-first= Hans R. |editor1-last=Thierstein |editor2-first= Jeremy R. |editor2-last=Young |title=Coccolithophores-from molecular processes to global impact |publisher=Springler |date=August 17, 2004 |location=Berlin |chapter=Species level variation in coccolithophores= |isbn=9783540219286 |pages=1–29 |display-authors=etal  }}.</ref> While most modern coccolithophores can be located in their associated stratified [[oligotrophic]] conditions, the most abundant areas of coccolithophores where there is the highest species diversity are located in subtropical zones with a temperate climate.<ref name=Jordan1997>{{citation |journal=Biodiversity & Conservation |volume=6 |issue=1 |year=1997 |pages=131–152 |title=Biodiversity among haptophyte algae |first1=R. W. |last1=Jordan |first2=A.H.L. |last2=Chamberlain|doi=10.1023/A:1018383817777 |s2cid=9564456 }}</ref> While water temperature and the amount of light intensity entering the water's surface are the more influential factors in determining where species are located, the ocean currents also can determine the location where certain species of coccolithophores are found.<ref name=Boeckel2006>{{citation |journal=Deep-Sea Research Part I: Oceanographic Research Papers |volume=53 |issue=6 |year=2006 |pages=1073–1099 |title=Coccolith distribution patterns in South Atlantic and Southern Ocean surface sediments in relation to environmental gradients |last1=Boeckel |doi=10.1016/j.dsr.2005.11.006|last2=Baumann |first2=Karl-Heinz |last3=Henrich |first3=Rüdiger |last4=Kinkel |first4=Hanno |bibcode = 2006DSRI...53.1073B |display-authors=etal}}</ref>

Although motility and colony formation vary according to the life cycle of different coccolithophore species, there is often alternation between a motile, haploid phase, and a non-motile diploid phase.  In both phases, the organism's dispersal is largely due to ocean [[current (ocean)|current]]s and circulation patterns.<ref name=deVargas2007 />

Within the Pacific Ocean, approximately 90 species have been identified with six separate zones relating to different Pacific currents that contain unique groupings of different species of coccolithophores.<ref name=Okada1973>{{citation |journal=Deep-Sea Research and Oceanographic Abstracts  |volume=20 |issue=4 |year=1973 |pages=355–374 |title=The distribution of oceanic coccolithophores in the Pacific |last1=Okada |doi=10.1016/0011-7471(73)90059-4|last2=Honjo |first2=Susumu |bibcode = 1973DSRA...20..355O |display-authors=etal}}</ref> The highest diversity of coccolithophores in the Pacific Ocean was in an area of the ocean considered the Central North Zone which is an area between 30 <sup>o</sup>N and 5 <sup>o</sup>N, composed of the North Equatorial Current and the Equatorial Countercurrent. These two currents move in opposite directions, east and west, allowing for a strong mixing of waters and allowing a large variety of species to populate the area.<ref name=Okada1973 />

In the Atlantic Ocean, the most abundant species are ''[[emiliania huxleyi|E. huxleyi]]'' and ''Florisphaera profunda'' with smaller concentrations of the species ''Umbellosphaera'' ''irregularis'', ''Umbellosphaera tenuis'' and different species of ''Gephyrocapsa''.<ref name=Okada1973 /> Deep-dwelling coccolithophore [[species abundance]] is greatly affected by [[nutricline]] and [[thermocline]] depths. These coccolithophores increase in abundance when the nutricline and thermocline are deep and decrease when they are shallow.<ref name=Kinkel2000>{{citation |journal=Marine Micropaleontology |volume=39 |issue=1–4 |year=2000 |pages=87–112 |title=Coccolithophores in the equatorial Atlantic Ocean: response to seasonal and Late Quaternary surface water variability |first=H. |last=Kinkel |doi=10.1016/s0377-8398(00)00016-5 |display-authors=etal  |bibcode=2000MarMP..39...87K }}</ref>

[[File:Comparative coccolithophore sizes.png|thumb|right|280px|Size comparison between the relatively large coccolithophore ''Scyphosphaera apsteinii'' and the relatively small but ubiquitous coccolithophore ''[[Emiliania huxleyi]]''<ref>Gafar, N. A., Eyre, B. D. and Schulz, K. G. (2019). "A comparison of species specific sensitivities to changing light and carbonate chemistry in calcifying marine phytoplankton". ''Scientific Reports'', '''9'''(1): 1–12. {{doi|10.1038/s41598-019-38661-0}}. [[File:CC-BY icon.svg|50px]] Material was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref>]]

The complete distribution of coccolithophores is currently not known and some regions, such as the Indian Ocean, are not as well studied as other locations in the Pacific and Atlantic Oceans. It is also very hard to explain distributions due to multiple constantly changing factors involving the ocean's properties, such as coastal and equatorial [[upwelling]], frontal systems, [[benthic]] environments, unique oceanic topography, and pockets of isolated high or low water temperatures.<ref name="Young2009"/>
<!-- Deleted image removed: [[File:Table 1Cocco.jpg|frame|alt=Table 1|Table 1. Biogeographic coccolithophorid assemblages; adapted from Jordan, et Al., 1997.<ref name=Jordan1997 />]]
  -- Deleted image removed: [[File:Table 2Cocco.jpg|frame|alt=Table 1|Table 2. Depth-related coccolithophorid assemblages in subtropic waters; adapted from Jordan, et Al., 1997.<ref name=Jordan1997 /> The upper photic zone is low in nutrient concentration, high in light intensity and penetration, and usually higher in temperature. The lower photic zone is high in nutrient concentration, low in light intensity and penetration and relatively cool. The middle photic zone is an area that contains the same values in between that of the lower and upper photic zones.]] -->

The upper photic zone is low in nutrient concentration, high in light intensity and penetration, and usually higher in temperature. The lower photic zone is high in nutrient concentration, low in light intensity and penetration and relatively cool. The middle photic zone is an area that contains the same values in between that of the lower and upper photic zones.<ref name=Jordan1997 />

{{multiple image
 | align     = left
 | direction = horizontal
 | footer    = Larger coccolithophores such as the species above are less numerous than the smaller but ubiquitous ''[[Emiliania huxleyi]]'', but they are heavily calcified and make important contributions to global calcification.<ref>Daniels, C.J., Sheward, R.M. and Poulton, A.J. (2014) "Biogeochemical implications of comparative growth rates of ''Emiliania huxleyi'' and ''Coccolithus'' species". ''Biogeosciences'', '''11'''(23): 6915–6925. {{doi|10.5194/bg-11-6915-2014}}.</ref><ref>Durak, G.M., Taylor, A.R., Walker, C.E., Probert, I., De Vargas, C., Audic, S., Schroeder, D., Brownlee, C. and Wheeler, G.L. (2016) "A role for diatom-like silicon transporters in calcifying coccolithophores". ''Nature communications'', '''7''': 10543. {{doi|10.1038/ncomms10543}}. [[File:CC-BY icon.svg|50px]] Material was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref> Unmarked scale bars 5&nbsp;μm.
 | width1    = 200
 | image1    = Calcidiscus leptoporus.png
 | caption1  = ''Calcidiscus leptoporus''
 | width2    = 188
 | image2    = Coccolithus braarudii.png
 | caption2  = ''[[Coccolithus|Coccolithus braarudii]]''
 | width3    = 212
 | image3    = Scyphosphaera apsteinii.png
 | caption3  = ''Scyphosphaera apsteinii''
}}

{{clear}}

====Great Calcite Belt====
[[File:Great Calcite Belt of the Southern Ocean.webm|thumb|upright=2|Yearly cycle of the [[Great Calcite Belt]] in the Southern Ocean]]
{{Main|Great Calcite Belt}}

The [[Great Calcite Belt]] of the [[Southern Ocean]] is a region of elevated summertime upper ocean calcite concentration derived from coccolithophores, despite the region being known for its [[diatom]] predominance. The overlap of two major phytoplankton groups, coccolithophores and diatoms, in the dynamic frontal systems characteristic of this region provides an ideal setting to study environmental
influences on the distribution of different species within these taxonomic groups.<ref name=Smith2017>{{cite journal |doi = 10.5194/bg-14-4905-2017|title = The influence of environmental variability on the biogeography of coccolithophores and diatoms in the Great Calcite Belt|year = 2017|last1 = Smith|first1 = Helen E. K.|last2 = Poulton|first2 = Alex J.|last3 = Garley|first3 = Rebecca|last4 = Hopkins|first4 = Jason|last5 = Lubelczyk|first5 = Laura C.|last6 = Drapeau|first6 = Dave T.|last7 = Rauschenberg|first7 = Sara|last8 = Twining|first8 = Ben S.|last9 = Bates|first9 = Nicholas R.|last10 = Balch|first10 = William M.|journal = Biogeosciences|volume = 14|issue = 21|pages = 4905–4925|bibcode = 2017BGeo...14.4905S|doi-access = free}} [[File:CC-BY icon.svg|50px]] Material was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref>

The Great Calcite Belt, defined as an elevated [[particulate inorganic carbon]] (PIC) feature occurring alongside seasonally elevated [[chlorophyll a]] in [[Wiktionary:austral|austral]] spring and summer in the Southern Ocean,<ref name=Balch2005>{{cite journal |doi = 10.1029/2004JC002560|title = Calcium carbonate measurements in the surface global ocean based on Moderate-Resolution Imaging Spectroradiometer data|year = 2005|last1 = Balch|first1 = W. M.|last2 = Gordon|first2 = Howard R.|last3 = Bowler|first3 = B. C.|last4 = Drapeau|first4 = D. T.|last5 = Booth|first5 = E. S.|journal = Journal of Geophysical Research|volume = 110|issue = C7|pages = C07001|bibcode = 2005JGRC..110.7001B|doi-access = free}}</ref> plays an important role in climate fluctuations,<ref>{{cite journal |doi = 10.1038/30455|title = Simulated response of the ocean carbon cycle to anthropogenic climate warming|year = 1998|last1 = Sarmiento|first1 = Jorge L.|last2 = Hughes|first2 = Tertia M. C.|last3 = Stouffer|first3 = Ronald J.|last4 = Manabe|first4 = Syukuro|journal = Nature|volume = 393|issue = 6682|pages = 245–249|bibcode = 1998Natur.393..245S|s2cid = 4317429}}</ref><ref>{{cite journal |doi = 10.1029/2003GB002134|title = Response of ocean ecosystems to climate warming|year = 2004|last1 = Sarmiento|first1 = J. L.|last2 = Slater|first2 = R.|last3 = Barber|first3 = R.|last4 = Bopp|first4 = L.|last5 = Doney|first5 = S. C.|last6 = Hirst|first6 = A. C.|last7 = Kleypas|first7 = J.|last8 = Matear|first8 = R.|last9 = Mikolajewicz|first9 = U.|last10 = Monfray|first10 = P.|last11 = Soldatov|first11 = V.|last12 = Spall|first12 = S. A.|last13 = Stouffer|first13 = R.|journal = Global Biogeochemical Cycles|volume = 18|issue = 3|pages = n/a|bibcode = 2004GBioC..18.3003S|hdl = 1912/3392| s2cid=15482539 | url=https://hal.archives-ouvertes.fr/hal-03129787/file/2003GB002134.pdf |hdl-access = free}}</ref> accounting for over 60% of the Southern Ocean area (30–60° S).<ref name=Balch2011>{{cite journal |doi = 10.1029/2011JC006941|title = The contribution of coccolithophores to the optical and inorganic carbon budgets during the Southern Ocean Gas Exchange Experiment: New evidence in support of the "Great Calcite Belt" hypothesis|year = 2011|last1 = Balch|first1 = W. M.|last2 = Drapeau|first2 = D. T.|last3 = Bowler|first3 = B. C.|last4 = Lyczskowski|first4 = E.|last5 = Booth|first5 = E. S.|last6 = Alley|first6 = D.|journal = Journal of Geophysical Research|volume = 116|issue = C4|pages = C00F06|bibcode = 2011JGRC..116.0F06B}}</ref> The region between 30° and 50° S has the highest uptake of anthropogenic carbon dioxide (CO<sub>2</sub>) alongside the North Atlantic and North Pacific oceans.<ref>{{cite journal |doi = 10.1126/science.1097403|title = The Oceanic Sink for Anthropogenic CO2|year = 2004|last1 = Sabine|first1 = C. L.|last2 = Feely|first2 = R. A.|last3 = Gruber|first3 = N.|last4 = Key|first4 = R. M.|last5 = Lee|first5 = K.|last6 = Bullister|first6 = J. L.|last7 = Wanninkhof|first7 = R.|last8 = Wong|first8 = C. S.|last9 = Wallace|first9 = D. W.|last10 = Tilbrook|first10 = B.|last11 = Millero|first11 = F. J.|last12 = Peng|first12 = T. H.|last13 = Kozyr|first13 = A.|last14 = Ono|first14 = T.|last15 = Rios|first15 = A. F.|journal = Science|volume = 305|issue = 5682|pages = 367–371|pmid = 15256665|bibcode = 2004Sci...305..367S|s2cid = 5607281|url = http://oceanrep.geomar.de/46251/1/1193.full.pdf}}</ref>

====Effect of global climate change on distribution====
Recent studies show that climate change has direct and indirect impacts on Coccolithophore distribution and productivity. They will inevitably be affected by the increasing temperatures and thermal stratification of the top layer of the ocean, since these are prime controls on their ecology, although it is not clear whether global warming would result in net increase or decrease of coccolithophores. As they are calcifying organisms, it has been suggested that [[ocean acidification]] due to increasing carbon dioxide could severely affect coccolithophores.<ref name="Kinkel2000"/> Recent {{CO2}} increases have seen a sharp increase in the population of coccolithophores.<ref>{{cite news |url=http://www.csmonitor.com/Science/2015/1128/What-s-fueling-the-rise-of-coccolithophores-in-the-oceans |title=What's fueling the rise of coccolithophores in the oceans? |last1=Gitau |first1=Beatrice |date=28 November 2015 |website=www.csmonitor.com |publisher=The Christian Science Monitor |access-date=30 November 2015}}</ref>