From the above diagram, we got to know about the various characteristics of living organisms. Some of them are respiration, growth, reproduction of living organisms and the need for food to stay alive. Aquatic habitat may be defined as bodies of water where organisms naturally live in. Simply put, it is a water area serving as home to a variety of organisms. The living creatures dwelling here are generally termed aquatic organisms, and they find their food, shelter and mates within the waterbody. Here are a few things that can be done to help conserve and protect the aquatic habitat including both marine and freshwater ecosystems. Within the components of the aquatic habitat that make life in water possible, we can distinguish between: The marine habitat can be grouped into zones with regards to its varying water depths and shoreline features. These zones include:

Helm, Rebecca R. (28 April 2021). "The mysterious ecosystem at the ocean's surface". PLOS Biology. Public Library of Science (PLoS). 19 (4): e3001046. doi: 10.1371/journal.pbio.3001046. ISSN 1545-7885. PMC 8081451. PMID 33909611. {{ cite journal}}: CS1 maint: unflagged free DOI ( link) Material was copied from this source, which is available under a Creative Commons Attribution 4.0 International License. The largest animal ever to live on Earth is an ocean mammal called the blue whale. It’s as long as two school buses! Dolphins, porpoises, and sea lions are also ocean-dwelling mammals. Temperature, ocean depth, and distance from the shore determine the types of plants and animals living in an area of the ocean. These regions are called habitats. Horppila, Jukka; Kaitaranta, Joni; Joensuu, Laura; Nurminen, Leena (2013). "Influence of emergent macrophyte (Phragmites australis) density on water turbulence and erosion of organic-rich sediment". Journal of Hydrodynamics. 25 (2): 288–293. Bibcode: 2013JHyDy..25..288H. doi: 10.1016/S1001-6058(13)60365-0. S2CID 120990795.

Animals that live in aquatic habitat

Examples of freshwater plants include spirogyra, water lettuce, algae, water lily, cattails, water weed, aspen, and willow trees. The animal community present in freshwater include alligators, snakes, frogs, lake trout, mayfly, hippopotamus, crocodiles, herons, kingfisher, crayfish, catfish, freshwater crab, and a variety of fishes and insects. Ocean Habitats and Information". 5 January 2017. Archived from the original on 1 April 2017 . Retrieved 1 December 2018. Aquatic plants have adapted to live in either freshwater or saltwater. Aquatic vascular plants have originated on multiple occasions in different plant families; [6] [11] they can be ferns or angiosperms (including both monocots and dicots). The only angiosperms capable of growing completely submerged in seawater are the seagrasses. [12] Examples are found in genera such as Thalassia and Zostera. An aquatic origin of angiosperms is supported by the evidence that several of the earliest known fossil angiosperms were aquatic. Aquatic plants are phylogenetically well dispersed across the angiosperms, with at least 50 independent origins, although they comprise less than 2% of the angiosperm species. [13] Archaefructus represents one of the oldest, most complete angiosperm fossils which is around 125 million years old. [14] These plants require special adaptations for living submerged in water or floating at the surface. [14] Aquatic adaptation [ edit ] Reproduction [ edit ]

can keep CO 2 levels satisfactory, even in basic environments with low carbon levels. [15] Buoyancy [ edit ] Thomaz, Sidinei M.; Dibble, Eric D.; Evangelista, Luiz R.; Higuti, Janet; Bini, Luis M. (2007). "Influence of aquatic macrophyte habitat complexity on invertebrate abundance and richness in tropical lagoons". Freshwater Biology: 358–367. doi: 10.1111/j.1365-2427.2007.01898.x. There are many species of emergent plants, among them, the reed ( Phragmites), Cyperus papyrus, Typha species, flowering rush and wild rice species. Some species, such as purple loosestrife, may grow in water as emergent plants but they are capable of flourishing in fens or simply in damp ground. [27] Submerged [ edit ] a b Shtein, Ilana; Popper, Zoë A.; Harpaz-Saad, Smadar (2017-07-03). "Permanently open stomata of aquatic angiosperms display modified cellulose crystallinity patterns". Plant Signaling & Behavior. 12 (7): e1339858. doi: 10.1080/15592324.2017.1339858. ISSN 1559-2324. PMC 5586356. PMID 28718691.Plants and animals in an aquatic ecosystem show a wide variety of adaptations which may involve life cycle, physiological, structural and behavioural adaptations. Majority of aquatic animals are streamlined which helps them to reduce friction and thus save energy. Fins and gills are the locomotors and respiratory organs respectively. Special features in freshwater organisms help them to drain excess water from the body. Aquatic plants have different types of roots which help them to survive in water. Some may have submerged roots; some have emergent roots or maybe floating plants like water hyacinths. Open sea: habitats with greater depth than the previous case, therefore with less incidence of light and colder. These habitats enable the development of herbivorous and omnivorous biodiversity. An emergent plant is one which grows in water but pierces the surface so that it is partially exposed to air. Collectively, such plants are emergent vegetation. Terrestrial plants may undergo physiological changes when submerged due to flooding. When submerged, new leaf growth has been found to have thinner leaves and thinner cell walls than the leaves on the plant that grew while above water, along with oxygen levels being higher in the portion of the plant grown underwater versus the sections that grew in their terrestrial environment. [24] This is considered a form of phenotypic plasticity as the plant, once submerged, experiences changes in morphology better suited to their new aquatic environment. [24] However, while some terrestrial plants may be able to adapt in the short-term to an aquatic habitat, it may not be possible to reproduce underwater, especially if the plant usually relies on terrestrial pollinators.