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Diversity within the marine biome
Oceans can be classified into four zones: intertidal, pelagic, abyssal, and benthic. Each zone contains a great diversity of species, more diversity than land-dwellers, despite the fact that fewer species exist.
The intertidal zones are coasts. This is where the ocean meets the land. Whether the coast is a cliff, rocky, sandy, or muddy - it is still classified as an intertidal zone. In this zone, species must exist to be able to withstand a constantly changing environment. Because of the moon's gravitational pull on the water, tides are formed. Organisms on the coasts are subjected to submersion in and out of the water; therefore they need to be adapted to survive in both conditions for certain periods of times.
Rocky shores provide the most life of all the intertidal zones because of their ability to serve as homes for protection for animals. At the highest level of the tide, you will not see much life due to the fact that aquatic creatures can not be exposed to air for very long. Only a few species of plants and mollusks are able to survive up there. However, the lower you go, the more life you will see that exists.
In the lowest ends you can find many kinds of plants and small animals. Some are herbivorous snails, crabs, sea stars, and small fishes. In the extreme bottom, , many invertebrates, fishes, and seaweed can be sneen. However, due to the quality of sandy and muddy shores, the ground is constantly moving. Few plants and animals are able to service, but the list increase worms, clams, predatory crustaceans, crabs, and shorebirds.
If you are exceptionally interested, you may click here to see an illustration of what an intertidal zone looks like.
The pelagic zone is the water that is far enough away from the land that you can't see the land itself. This zone features abundant plankton, which are microscopic organisms that serve as the basis of the food chain in the ocean. This zone consists of many organisms, including many species of fish, mammals, whales, and dolphins - many of which feed on the plankton.
The benthic zone is the area that is below than the pelagic zone. It does not have a geographically distinct description (as in you can look at a map to identify it). The key thing is that it is deeper than the pelagic zone. The bottom of this zone consists of sand, slit, and possibly (depending on where you look) some dead organisms. The living organisms include seaweed, bacteria, fungi, sponges, sea anemones, worms, sea stars, and fishes. These are species that do not necessarily need much light, because over the years they have become adapted to their dark environment.
The deepest part of the ocean is called the abyssal zone. The water here is at a very high pressure. Surprisingly to most people, the water is rich in oxygen, but low in nutritional content. This zone supports several different species of invertebrates and fish. Mid-ocean ridges (these are spreading zones between tectonic plates, often accompanied by hydrothermal vents (holes in the plates leaking magma), can be found in the abyssal zones along the ocean's floor. Chemosynthetic bacteria (bacteria that can produce their own food) thrive near these vents because of the large amounts of hydrogen sulfide and other minerals that are emitted. To see a picture of what one of these looks like, you can click here. Thus, these bacteria serve as the start of the food web in the ocean as they are eaten by invertebrates and fish.
