Basic Facts About Marine Habitats

Oceans cover approximately 70% of the earth’s surface with an average depth of 2.4 miles, or 3,800 meters. The marine ecosystem, in addition to the temperate and tropical oceans, includes the shorelines, with mud flats, rocky and sandy shores, tidepools, barrier islands, estuaries, salt marshes, and mangrove forests making up the shoreline segment. Marine ecosystems support a great diversity of life and variety of habitats. The ocean is a major influence on weather and climate.


Conventionally, the ocean has been divided into four major ocean basins: Atlantic, Pacific, Indian and Arctic oceans. Specific marine ecosystems such as coral reefs, estuaries, salt mashes, mangrove forests are found throughout the world, but are characteristic of certain areas, depending on climate, geography, water temperature, and other physical factors.


Marine habitats are the home to seaweeds, or marine algae (brown, green, red), sea grasses, which are the only marine flowering plants, and mangroves, located on muddy tropical shores.


Marine ecosystems are homes to protozoans, marine invertebrates (echinoderms, mollusks, segmented and non-segmented worms, jellies, coral, sea anemones, hyroids) marine vertebrates (fishes, birds, mammals), and plankton (phyto and zooplankton).


Monsoon, tropical, subtropical, temperate, polar, subpolar

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