Editing Ecoregion (section)

== Marine ==
<!-- This section is the link target for [[Marine ecoregion]] and [[Wild fisheries]] -->
{{Main|Marine ecoregion}}
{{See also|Large marine ecosystem}}

[[File:The Earth seen from Apollo 17.jpg|thumb|upright|left|View of Earth, taken in 1972 by the [[Apollo 17]] crew. Approximately 71% of [[Earth#Surface|Earth's surface]] (an area of some 361 million square kilometers) consists of [[ocean]]]]

[[Marine ecoregion]]s are: "Areas of relatively homogeneous [[species composition]], clearly distinct from adjacent systems….In ecological terms, these are strongly cohesive units, sufficiently large to encompass ecological or life history processes for most sedentary species."<ref name="nature573">{{cite journal|last1=Spalding |first1=Mark D. |first2=Helen E. |last2=Fox |first3=Gerald R. |last3=Allen |first4=Nick |last4=Davidson |title= Marine Ecoregions of the World: A Bioregionalization of Coastal and Shelf Areas |volume= 57 |issue= 7 |pages= 573–583 |journal= BioScience |url=https://academic.oup.com/bioscience/article/57/7/573/238419/Marine-Ecoregions-of-the-World-A#b1|display-authors=etal|doi= 10.1641/B570707 |year= 2007 |s2cid= 29150840 |url-access=subscription }}</ref> They have been defined by The Nature Conservancy (TNC) and World Wildlife Fund (WWF) to aid in [[Conservation (ethic)|conservation]] activities for [[marine ecosystems]]. Forty-three priority marine ecoregions were delineated as part of WWF's Global 200 efforts.<ref>Olson and Dinerstein 1998 and 2002</ref> The scheme used to designate and classify marine ecoregions is analogous to that used for terrestrial ecoregions. Major habitat types are identified: polar, temperate shelves and seas, temperate upwelling, tropical upwelling, tropical coral, pelagic (trades and westerlies), abyssal, and hadal (ocean trench). These correspond to the terrestrial [[biomes]].

The Global 200 classification of marine ecoregions is not developed to the same level of detail and comprehensiveness as that of the terrestrial ecoregions; only the priority conservation areas are listed.

See Global 200 Marine ecoregions for a full list of marine ecoregions.<ref name="worldwildlife1">{{cite web |publisher=World Wide Fund for Nature |url=http://www.worldwildlife.org/science/ecoregions/marine/item1266.html |title=Marine Ecoregions of the World }}</ref>

In 2007, TNC and WWF refined and expanded this scheme to provide a system of comprehensive near shore (to 200 meters depth) Marine Ecoregions of the World (MEOW).<ref name="worldwildlife1"/> The 232 individual marine ecoregions are grouped into 62 [[marine provinces]], which in turn group into 12 [[marine realms]], which represent the broad latitudinal divisions of polar, temperate, and tropical seas, with subdivisions based on ocean basins (except for the southern hemisphere temperate oceans, which are based on continents).

Major marine biogeographic realms, analogous to the eight terrestrial [[biogeographic realm]]s, represent large regions of the ocean basins: [[Arctic Ocean|Arctic]], [[Temperate Northern Atlantic]], [[Temperate Northern Pacific]], [[Tropical Atlantic]], [[Western Indo-Pacific]], [[Central Indo-Pacific]], [[Eastern Indo-Pacific]], [[Tropical Eastern Pacific]], [[Temperate South America]], [[Temperate Southern Africa]], [[Temperate Australasia]], and [[Southern Ocean]].<ref name="nature573"/>

A similar system of identifying areas of the oceans for conservation purposes is the system of large marine ecosystems (LMEs), developed by the US [[National Oceanic and Atmospheric Administration]] (NOAA).