Marine Biology

Terminology definition

Marine biology is a branch of science that deals with study of organisms that live in oceans, sea water or brackish water. Marine biology is classified on the basis of environmental conditions prevailing in and around rather than on taxonomy. Marine ecology is entirely different from marine biology. Marine ecology deals with interaction of marine organisms with the environment. Marine organisms serve as sources for food, medicinal raw materials etc. They include microscopic organisms like phytoplankton, zooplankton and macroscopic organisms like whales or crustaceans.One such crustaceans was measured to be 48 meters in length.

Marine biologists study surface tension that exists between ocean and environment, depth of the ocean, depth of trenches and size of the organism. Marine biologists study marine habitats like coral reefs, rocky pools and kelp forests. Huge amount of life exist in oceans. Marine organisms’ numbers are not yet predicted.

Habitat types

Marine habitat types are as follows.

• Reefs
• Deep sea and trenches
• Open ocean
• Intertidal and shore
  

Reefs:

Reefs are diversified habitat of marine organisms in the world. For instance, a tropical coral reef is abundant in tropical waters. Reefs can survive in the cold water too. They are made of corals and calcium depositing animals. Artificial reefs can be created if it grows on any other surface. Once in thousand years, due to bleaching events like that of 1998, many coral reefs died due to increase in temperature. This confirms the global warming danger to marine life.

Deep sea and trenches:

Small flounder fish and shrimps are seen in deepest oceanic trenches where the water pressure is extremely high without any illumination. Aphotic zone is starting point of deep sea. At this zone, light transference through water is difficult. But, with the help of bioluminescence, some organisms exist at this aphotic zone.

Open ocean:

Open ocean is widely diversified area where the nutrients content are very less. It helps in primary production. Aphotic zone energy is given by the open ocean habitats which exist in the form of detritus. The organisms such as jelly fish and mola mola predators also exist in open ocean.

Intertidal and shore:

Marine organisms are widely seen in intertidal zone which is close to the shore and where ocean tides are abundant. Upper intertidal zones where vegetations take place are referred as shores. An organism like scavengers exists. It is also inhabitated by many animals.

Ecoregion classification

• Littoral zone: The zone which are near the sea shore.
• Intertidal zone: Zone which is exposed to air low tide and underwater high tide.
• Estuaries: Zone with branch of fresh water streams connected to sea.
• Ocean bank: Shallow continental zone is referred as ocean bank.
• Continental shelf: Part of continent formed during glacial period.
• Neritic zone: Sub littoral zone or coastal ocean
• Straits: Two larger areas of ocean are connected by navigable channel of water.
•  Pelagic zone: Zone near or at the bottom of sea.
• Oceanic zone: Off shore area zone.
• Sea mount: Ocean seafloor with mountain appearance.
• Demersal zone: Zone above benthic zone resulting in profound zone.
• Benthic zone: Lowest level of water body extending to continental shelf.

Distribution

A marine form exists as nests as juveniles. Marine biologists help in exploration of life cycles of many marine forms. It is a challenge for research scientists and fishermen to know where the species exist and use of technology in ocean to track their current trend. Advancement in GPS technology and visual equipments, it has become recently feasible to predict how tides and oceanic currents affect the marine forms and their distribution.

Types of marine bio- forms

Microscopic marine forms are phytoplankton such as cyanobacteria, diatoms, algae and zooplanktons such as zooflagellates, mollusks, arthropods and annelids. Marine plant forms are kelp, sargassum, mangroves, beach grass and cord grass. Other instances of marine forms are jelly fish, sea worms, shell fish, sharks, whales, star fish, sea squirts, squid, octopus, crustacean, bryozoans and porifera. Marine reptiles are sea snake, sea turtles, saltwater crocodile and marine iguana. Marine birds like penguins, auks, gannets, gulls and marine mammals like polar bear, seals, sea lions, cetaceans, blue whale and sea otter.