People have long been accustomed to the existence of a diverse animal and plant world on land. And what do we know about life in the ocean? How diverse is it? Who, apart from commercial fish, can be found in its waters? Let's look for answers to these questions together.
Amazing variety
Life in the ocean is amazing and diverse. Scientists are confident that life began its development precisely in the waters of the oceans. This can explain the fact that more than 150 thousand different species of representatives of the animal and plant world live here. If you try to calculate the total weight of all life forms of ocean waters, then the figure will be huge - in fact, it is 60 billion tons. The ocean as a habitat is suitable for all types of the organic world. Here you can find both simple organisms and huge mammals. Of the huge variety of wildlife in the ocean, only spiders, centipedes and amphibian animals did not take root.
Differences between water and air
To argue that the air and water habitats differ in physical properties is unpromising. In the aquatic environment, temperatures are differently distributed, in accordance with the depth, the water pressure increases. And the presence of sunlight is observed only in the upper layers. These features of life in the ocean affect the existence and development of all living things.
So, due to the fact that water is able to support organisms in a certain position, they do not need to form especially strong skeletons or roots. Therefore, life in the ocean is represented by the largest mammal in nature, which is called the blue whale. This animal is 25 times heavier than the largest inhabitant of the land - the elephant.
Well, since ocean algae do not have to resist the air element, they do not need to grow a powerful root system, but at the same time they can stretch for several tens of meters.
What is benthos?
This incomprehensible word defines the totality of living creatures living on and in the ocean ground. At the bottom of the ocean there are two varieties of life: zoobenthos and phytobenthos. Representatives of zoobenthos, that is, the animal world, are much larger, and as they approach the shores of the continents and islands, their number increases in shallow water.
Zoobenthos are crustaceans, mollusks, large and small fish. Phytobenthos includes various bacteria and algae.
What is plankton?
Well, what is life in the ocean without plankton? These are special living organisms that are not attached to the bottom, but are also not able to actively move. Virtually all movements of plankton occur due to currents. The upper layers of water, where sunlight enters, inhabit phytoplankton. It consists of various types of algae. But zooplankton lives in the entire water column.
Most of the animal plankton are crustaceans and protozoa. These are various ciliates, radiolarians and other representatives. In addition, there are intestinal organisms: siphonophores, jellyfish, ctenophores, and small winged leg mollusks.
Due to the huge amount of plankton, fish and aquatic animals are always provided with plentiful food.
What is nekton?
The term "nekton" is not found very often, but it means life forms that we are well aware of. Necton - organisms that can actively move in water. These are turtles, pinnipeds, and cetaceans. The nekton also includes all kinds of fish, squid, penguins and water snakes.
Zone Division
Life in the ocean is interesting because it creates unequal conditions for inhabitants of various depths. So, shallow water off the coast is called the littoral zone. Here, unrest, ebbs and flows are commonplace. This made living organisms adapt to the daily shift in water and air. In addition, these organisms are constantly affected by temperature fluctuations, changes in salinity and surf. To survive in these conditions, the mollusks are firmly fixed on the rocks, the crabs are held by tenacious claws, the fish have acquired special suction cups. And shrimp and starfish learned to dig into the ground.
The next zone is the bathyal. It begins at a depth of 200 m, and ends at a depth of 2000 m. The bathy zone is located within the continental slopes. The plant world of this zone is very poor, because the sun's rays do not fall at such a depth. But there are many fish.
Further, the habitat is called abyssal. It is located at depths of more than two km. There is inactive water and stable low temperature. The salinity of the ocean at this depth can reach 34.7%, the light is completely absent. The vegetation in this area is represented by species of bacteria and algae. And the animal world of the ocean depths is very unusual. The bodies of animals are delicate and fragile. Many species have acquired long appendages to lean on viscous soil and be able to move around. Some living organisms have huge eyes, while others are completely absent. Many species of deep-sea fish are flat; some organisms are able to glow.
The deep-sea flora and fauna are still not fully understood, since the descent to great depths is difficult not only for humans, but also for research instruments. Widespread research using self-propelled bathyscaphe. But the life of the littoral and bathyal zones is being actively studied.
The wealth of the oceans gives mankind a huge food source. And most importantly, this power source is rich in vitamins and easily digestible protein. Representatives of not only the animal, but also the plant world are suitable for food. The main thing is that a person does not find this source inexhaustible and learns to treat it with care and sparingly.