The organic world of the Atlantic Ocean depends on temperature, salinity and other indicators that characterize the water area of this part of the MO. Conditions for the life of organisms change significantly from north to south. Therefore, in the Atlantic there are areas rich in natural resources and relatively poor areas where the number of animal species is in the tens, not hundreds.
The role of living organisms in the natural complex of MO
The organic world of the Atlantic Ocean is significantly influenced by the large extent of the water area from north to south. The diversity of animals and plants is influenced by the vast areas of the continental shelf, land runoff and other natural factors. The sea, the bottom and the surf are home to thousands of organisms that belong to different kingdoms of the Earth's nature. Plants and animals are the most important components of the natural complex. They are influenced by climate, the composition and properties of water, rocks that make up the bottom. In turn, the organic world of the Atlantic Ocean affects other components of nature:
- algae enrich water with oxygen;
- respiration of plants and animals leads to an increase in carbon dioxide;
- Coelenterates skeletons form the backbone of coral reefs and atolls;
- living organisms absorb mineral s alts from water, reducing their amount.
Organic world of the Atlantic Ocean (briefly)
Temperature and salinity are critical for the microscopic living things that make up plankton, as well as algae. These indicators are important for nekton - animals floating freely in the water column. The features of the relief of the shelf and the ocean floor determine the vital activity of bottom organisms - benthos. This group includes many coelenterates and crustaceans. There are a number of features of the species composition that characterize the organic world of the Atlantic Ocean. The photo of the seabed below makes it possible to verify the diversity of benthos in subtropical and tropical latitudes. Fish-rich water areas are confined to areas of intensive plankton breeding in the temperate and hot zones. In the same regions, a diversity of seabirds and mammals is observed. The high latitudes in the north and south are dominated by birds that feed on the surface of water free of ice, and build nesting colonies on the coast.
Phytoplankton
Single-celled algae are an important part of plankton. This group includes diatoms, blue-green, flagella and others.the smallest living organisms capable of photosynthesis. They inhabit the water column up to 100 m deep, but the highest density is observed in the first 50 m from its surface. Intense solar radiation in the warm season leads to the rapid development of phytoplankton - the "bloom" of water in the temperate and subpolar latitudes of the Atlantic Ocean.
Large plants
Photosynthetic green, red, brown algae and other representatives of MO flora are an important part of the natural complex. Thanks to plants, the entire organic world of the Atlantic Ocean receives oxygen for breathing and nutrients. The list of bottom vegetation or phytobenthos includes not only algae, but also representatives of angiosperms that have adapted to living in s alt water, for example, the genera Zoster, Posidonius. These "sea grasses" prefer soft soils of the subtidal zone, forming underwater meadows at depths of 30 to 50 m.
Typical representatives of the flora of the continental shelf in the cold and temperate zones on both sides of the equator - kelp, red algae (crimson). They are attached to bottom rocks, single stones. Marine vegetation in the hot zone is poorer due to high temperatures and significant insolation. Economic importance of algae:
- brown (kelp) - eaten, serve to obtain iodine, potassium and algin;
- red algae - raw materials for the food and pharmaceutical industries;
- brown sargasso algae - the source of obtainingalgina.
Zooplankton
Phytoplankton and bacteria are food for herbivorous microscopic animals. Floating freely in the water column, they constitute zooplankton. It is based on the smallest representatives of crustaceans. Larger ones combine to form meso- and macroplankton (comb jelly, siphonophores, jellyfish, cephalopods, shrimps and small fish).
Nekton and benthos
There is a large group of living organisms in the ocean that can withstand the pressure of water, move freely in its thickness. Marine animals of medium and large sizes have such abilities.
- Crustaceans. Shrimps, crabs and lobsters belong to this subtype.
- Shells. Characteristic representatives of the group are scallops, mussels, oysters, squids and octopuses.
- Pisces. The genera and families of this superclass are the most numerous - anchovies, sharks, flounder, sprat, salmon, sea bass, capelin, sole, pollock, haddock, halibut, sardines, herring, mackerel, cod, tuna, hake.
- Reptiles. A few representatives are sea turtles.
- Birds. Penguins, albatrosses, petrels get food in the water.
- Marine mammals. Highly organized animals - dolphins, whales, fur seals, seals.
The basis of the benthos is made up of animals leading an attached lifestyle at the bottom, for example, coelenterates (coral polyps).
Features of plants andanimals of the Atlantic
- In the northern and southern parts of the basin, the presence of various species and genera in the fauna is noted.
- There are few types of plankton, but the total mass reaches impressive values, especially in the temperate climate zone. Diatoms, foraminifera, pteropods and copepods (krill) predominate.
- High bioproductivity is a sign that characterizes the features of the organic world of the Atlantic Ocean. It is distinguished by a significant density of life in shallow water near the island of Newfoundland, water areas to the southwest and northwest of the coast of Africa, marginal seas and the eastern shelf of the USA, South America.
- The tropical zone, as noted above, is an unfavorable area for phytoplankton.
- The nekton productivity of the Atlantic Ocean on the shelf and part of the continental slope is higher than in similar areas of neighboring oceans. Fish that feed on phyto- and zooplankton (anchovy, herring, mackerel, horse mackerel and others) predominate. In open waters, tuna are of commercial importance.
- Species richness of mammals is one of the features of the fauna of the Atlantic Ocean. In the past century, they have undergone significant extermination, the number has declined.
- Coral polyps are not as diverse as in the Pacific Basin. Few sea snakes, turtles.
There are various factors that explain many of the listed features that characterize the organic world of the Atlantic Ocean. The conclusion from everything said above suggests the following: the reasons for the differences are associated with the small width of the Atlantic in hot weather.belt, expanding in temperate and circumpolar regions. On the contrary, the Pacific and Indian Oceans have the greatest extent in the tropical zone. Another factor that influenced the relative poverty of the Atlantic in heat-loving animals is the influence of the last glaciation, which caused a significant cooling in the Northern Hemisphere.
Organic world of the Atlantic Ocean: fishery objects
Temperate and tropical latitudes in the northern and southern hemispheres are rich in life. Among the fish species of commercial importance are anchovies, pollock, tuna, cod, hake and others. Mammals are being hunted: whales and fur seals. Other types of biological resources are represented by molluscs, crustaceans, brown and red algae. Ocean plants are used for pet food and industrial processing. Most shellfish are delicacies, valued in the cuisine of many countries (oysters, squid, octopus, scallops). The same characteristic can be given to crustaceans, including lobsters, shrimp and crabs.
Fishing and seafood production are more intensively carried out on the shelf and in the area of continental slopes. But in recent decades, parts of the water area, which previously experienced not such a strong anthropogenic influence, have been involved in economic circulation. Therefore, environmental problems are exacerbated not only in coastal areas, but also in the entire ocean.
