{"id":1652,"date":"2015-04-29T11:19:57","date_gmt":"2015-04-29T11:19:57","guid":{"rendered":"http:\/\/www.bluehabitats.org\/?page_id=1652"},"modified":"2015-04-29T14:10:39","modified_gmt":"2015-04-29T14:10:39","slug":"abyssal-plains","status":"publish","type":"page","link":"https:\/\/bluehabitats.org\/?page_id=1652","title":{"rendered":"Abyssal plains"},"content":{"rendered":"
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Abyssal plains \u2013 <\/em>Abyssal plains are defined by the IHO (2008) as \u201cAn extensive, flat, gently sloping or nearly level region at abyssal depths.\u201d\u00a0 Sediment deposited adjacent to the continents forms the continental rise. Seaward of this, the land-derived sediment wedge may extend for hundreds of kilometers onto the ocean basins forming the flat abyssal plains.<\/p>\n

Abyssal plains are remarkably flat, having a slope of less than 1:1,000 (or less than 1 m change in height over a distance of 1 km), because of the thick sediment drape that covers and subdues most of the underlying basement topography. The GSFM classifies areas less than 300 m in relief as broadly correlating with abyssal plains.\u00a0 Ocean basins that receive the greatest sediment input have the best developed abyssal plains and are generally located adjacent to passive continental margins (e.g., the Atlantic and Indian oceans and the Gulf of Mexico). \u00a0Abyssal plains are poorly developed or absent adjacent to active continental margins because the ocean trench systems intercept and subduct land-derived sediments into the earth\u2019s mantle (eg. the North Pacific and the eastern South Pacific Oceans).<\/p>\n

Abyssal biota<\/em><\/strong><\/p>\n

The biology of animals that inhabit the deep ocean basins remains one of the least well studied subjects in the biological sciences (Gage and Tyler, 1991).\u00a0 In deep sea benthic environments, assemblages have been described for bathyal, abyssal and hadal depth zones, and there are clear differences in communities inhabiting rocky substrate versus soft substrate habitats.\u00a0 Animals that live in soft-sediments feed on detritus and often live within the sediments (infauna) such that the only sign of their existence in underwater photographs are the burrows in the mud where they live or the trails they leave in the mud from their feeding activities (known as Lebensspuren). Most bivalves live buried in the sediment and extend a siphon into the overlying water column to filter out food particles. Other animals crawl across the sediment, feeding on detritus.\u00a0 Animals that commonly occur in abyssal sediments include molluscs, worms (nematodes, sipunculids, polychaetes, hemichordates and vestimentiferans) and echinoderms (holothuroids, asteroids, ophiuroids, echinoids, and crinoids).<\/p>\n

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Images of Lebensspuren after Przeslawski et al. (2012).<\/p>\n\n\t\t<\/div>\n\t<\/div>\n<\/div><\/div><\/div><\/div>

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Abyssal classification categories (after Harris et al., 2014).\u00a0 The percentage areas first line refers to percentage of ocean basin area and the second line (in brackets) refers to percentage of abyssal area.<\/p>\n\n\t\t<\/div>\n\t<\/div>\n

[vc_table vc_table_theme=”classic_blue” allow_html=””]Ocean,Abyssal%20Plain%20Area%20km2,Abyssal%20Plain%20Area%25,Abyssal%20Hills%20Area%20km2,Abyssal%20Hills%20Area%20%25,Abyssal%20Mountains%20Area%20km2,Abyssal%20Mtns.%20Area%20%25%0A|Arctic%20Ocean%0AAbyssal,2%2C068%2C570,15.9%0A(38.7),2%2C244%2C920,17.3%0A(42),1%2C036%2C060,7.98%0A(19.4)|Indian%20Ocean%20%0AAbyssal,21%2C772%2C790,30.5%0A(34.7),30%2C179%2C170,42.3%0A(48),10%2C859%2C500,15.2%0A(17.3)|Mediterranean%20and%20Black%20Sea%20%20-%20Abyssal,612%2C870,20.3%0A(43.6),613%2C830,20.3%0A(43.7),179%2C220,5.93%0A(12.7)|North%20Atlantic%20Ocean%20Abyssal,10%2C255%2C540,22.9%0A(30.4),16%2C477%2C470,36.8%0A(48.9),6%2C987%2C830,15.6%0A(20.8)|North%20Pacific%20Ocean%20Abyssal,24%2C906%2C630,30.4%0A(36.2),29%2C676%2C230,36.2%0A(43.2),14%2C137%2C990,17.3%0A(20.6)|South%20Atlantic%20Ocean%20Abyssal,10%2C033%2C650,24.8%0A(27.4),19%2C511%2C510,48.3%0A(53.3),7%2C031%2C560,17.4%0A(19.2)|South%20Pacific%20Ocean%20Abyssal,22%2C648%2C400,26%0A(28),44%2C059%2C800,50.6%0A(54.4),14%2C299%2C470,16.4%0A(17.7)|Southern%20Ocean%20Abyssal,8%2C565%2C270,42.1%0A(50.4),6%2C688%2C370,32.9%0A(39.3),1%2C749%2C840,8.6%0A(10.3)|All%20Oceans%0AAll%20Abyssal,100%2C863%2C730,27.9%0A(32.9),149%2C451%2C310,41.3%0A(48.7),56%2C281%2C460,15.6%0A(18.4)[\/vc_table]<\/div><\/div><\/div><\/div>\n\t
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References<\/h5>\n

Harris, P.T., MacMillan-Lawler, M., Rupp, J., Baker, E.K., 2014. Geomorphology of the oceans. Marine Geology 352, 4-24.<\/p>\n

IHO, 2008. Standardization of Undersea Feature Names: Guidelines Proposal form Terminology, 4th ed. International Hydrographic Organisation and Intergovernmental Oceanographic Commission, Monaco, p. 32. http:\/\/www.iho.int\/iho_pubs\/bathy\/B-6_e4_EF_Nov08.pdf<\/a><\/p>\n\n\t\t<\/div>\n\t<\/div>\n<\/div><\/div><\/div><\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"

Abyssal plains \u2013 Abyssal plains are defined by the IHO (2008) as \u201cAn extensive, flat, gently sloping or nearly level region at abyssal depths.\u201d\u00a0 Sediment deposited adjacent to the continents forms the continental rise. Seaward of this, the land-derived sediment wedge may extend for hundreds of kilometers onto the ocean basins forming the flat abyssal…<\/p>\n","protected":false},"author":3,"featured_media":0,"parent":1646,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-1652","page","type-page","status-publish","hentry","description-off"],"acf":[],"_links":{"self":[{"href":"https:\/\/bluehabitats.org\/index.php?rest_route=\/wp\/v2\/pages\/1652","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bluehabitats.org\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/bluehabitats.org\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/bluehabitats.org\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/bluehabitats.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1652"}],"version-history":[{"count":8,"href":"https:\/\/bluehabitats.org\/index.php?rest_route=\/wp\/v2\/pages\/1652\/revisions"}],"predecessor-version":[{"id":1740,"href":"https:\/\/bluehabitats.org\/index.php?rest_route=\/wp\/v2\/pages\/1652\/revisions\/1740"}],"up":[{"embeddable":true,"href":"https:\/\/bluehabitats.org\/index.php?rest_route=\/wp\/v2\/pages\/1646"}],"wp:attachment":[{"href":"https:\/\/bluehabitats.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1652"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}