pelagic zone

pelagic zone

 ecological realm that includes the entire ocean water column. Of all the inhabited Earth environments, the pelagic zone has the largest volume, 1,370,000,000 cubic kilometres (330,000,000 cubic miles), and the greatest vertical range, 11,000 metres (36,000 feet). Pelagic life is found throughout the water column, although the numbers of individuals and species decrease with increasing depth. The regional and vertical distributions of pelagic life are governed by the abundance of nutrients and dissolved oxygen; the presence or absence of sunlight, water temperature, salinity, and pressure; and the presence of continental or submarine topographic barriers.

      Pelagic life consists of three categories. The phytoplankton, which constitute the food base of all marine animals, are microscopic organisms that inhabit only the sunlit uppermost oceanic layer, using sunlight to photosynthetically combine carbon dioxide and dissolved nutrient salts. zooplankton are the marine animals that rely mainly upon water motion for transport, although some forms such as jellyfish are feeble swimmers. Zooplankton subsist on phytoplankton and smaller zooplankton and are dominated in their numbers by small crustacean copepods and euphasiids. nekton, the free swimmers, are dominated by the bony and cartilaginous fishes, molluscans, and decapods, with rarer mammals and reptiles.

* * *


Universalium. 2010.

Игры ⚽ Нужно сделать НИР?

Look at other dictionaries:

  • Pelagic zone — Aquatic layers Pelagic    Photic       Epipelagic …   Wikipedia

  • pelagic zone — pelagialė statusas T sritis ekologija ir aplinkotyra apibrėžtis Jūrų ir vandenynų organizmų gyvenamoji aplinka viršutiniuose vandens sluoksniuose virš bentalės, kurioje gyvena bentosas. Horizontaliai skirstoma į 2 zonas: neritinę (atviro… …   Ekologijos terminų aiškinamasis žodynas

  • Pelagic fish — A school of large pelagic predator fish (giant trevally) sizing up a school of small pelagic prey fish (anchovies) Pelagic fish live near the surface or in the water column of coastal, ocean and lake waters, but not on the bottom of the sea or… …   Wikipedia

  • pelagic region — pelagialė statusas T sritis ekologija ir aplinkotyra apibrėžtis Jūrų ir vandenynų organizmų gyvenamoji aplinka viršutiniuose vandens sluoksniuose virš bentalės, kurioje gyvena bentosas. Horizontaliai skirstoma į 2 zonas: neritinę (atviro… …   Ekologijos terminų aiškinamasis žodynas

  • Pelagic Ecology of the Low Salinity San Francisco Estuary — Pelagic organisms spend all or part of their lives in the open water, where habitat isdefined not by edges but by physiological tolerance to salinity and temperature. The LowSalinity Zone (LSZ) of the San Francisco Estuary constitutes a habitat… …   Wikipedia

  • Pelagic sediments — Pelagic sediment or pelagite is a fine grained sediment that has accumulated by the settling of particles through the water column to the ocean floor beneath the open ocean far from land. These particles consist primarily of either the… …   Wikipedia

  • pelagic — PELÁGIC, Ă, pelagici, ce, adj. 1. (În sintagma) Zonă pelagică = totalitatea apelor din lacuri, mări şi oceane situate deasupra zonelor de fund (începând de la adâncimea de circa 200 m). ♦ Care se referă la zona definită mai sus, care aparţine… …   Dicționar Român

  • pelagic — [pi laj′ik] adj. [L pelagicus < Gr pelagos, the sea < IE * plāg , to spread out < base * plā > PLAIN1] of the ocean waters; esp., of the oceanic zone, as distinguished from the benthic regions of the ocean …   English World dictionary

  • pelagic — Zone above the sea bottom; or living free from the bottom [Butler, T.H.] …   Crustacea glossary

  • pelagic division — the biogeographic realm or zone that comprises the open seas and oceans, including water of all depths. Cf. benthos. [1890 95] * * * …   Universalium

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”