Comparative characteristics of birds and mammals. Birds and mammals Compare the skeleton of birds and mammals

Birds and mammals have common roots - the Reptile class, but due to a number of morphological and anatomical differences, these animals were able to master different living spaces.

Definition

Birds is a biological taxon, a class. They belong to the type of Chordata, the Animal Kingdom. A crow, a chicken, a sparrow, a penguin, or a peacock can be named as a typical representative of the class.

mammals is a biological taxon. Class Mammals belong to the phylum Chordata, the Animal Kingdom. Typical representatives of the class are hares, lions, cows, dolphins and walruses.

Comparison

Birds have a number of characteristic features that allowed them to be combined into one taxon. These are vertebrates like fish and quadrupeds. They are warm-blooded like mammals and oviparous like reptiles. A unique feature of these animals is the adaptation of the body to flight: it is covered with feathers, the upper limbs are modified into wings. A separate "pride" of birds is the beak, which no other species of Chordates has.

Martin. bird class

All mammals have a number of features that made it possible to distinguish them into one class. A little “lagging behind” in certain indicators from their colleagues are the first animals - platypuses and echidnas. But if every time you do not return to echidnas and platypuses, then all mammals are warm-blooded. Just like the birds. Most mammals are covered with hair or hair. They are engaged in live birth and feed their young with milk with the help of modified sweat glands.

The anatomical structure of birds is adapted to their ability to fly. Even those birds that do not fly today once had this skill. Or rather, not they, but their distant ancestors. The anatomical structure of a mammal depends on the environment in which it resides.

The skeleton of birds is simplified, strengthened and lightened. The bones of the skull are fused. They do not have prominent cranial sutures. There are four divisions in the spine, three of which are fused. The neck of birds is long and mobile. The girdle of the forelimbs changed into wings, while the reduction and fusion of some of them took place. Only birds have a keel attached to the ribs.

The skeleton of a mammal is represented by five sections (only cetaceans do not have a sacral). The skull of these animals is large, its bones have grown together, forming a protection for the developed brain.

In the digestive system of birds, the absence of teeth, an underdeveloped rectum and a high rate of metabolic processes were noted.

The respiratory system of a bird is adapted to enhanced gas exchange. In addition to lungs, they have lung sacs, thanks to which birds have “double breathing”. In mammals, the respiratory system is represented by lungs with bronchi. The diaphragm is involved in the process of breathing.

The circulatory system of a bird is represented by two circles of blood circulation and a four-chambered heart. The pulse of a bird in flight can reach a thousand (!) beats per minute. Mammals also have two circles of blood circulation and a four-chambered heart, but only in their blood there are non-nuclear highly specialized cells - erythrocytes.

Birds have well-developed eyesight, but the sense of smell is not developed. They don't smell. Some birds have intelligence. Animals have developed all the senses and marked intellectual abilities.

About 9800 species of birds live on Earth. They inhabit all continents and parts of the world, except for the central part of Antarctica. There are about 5,000 species of mammals on the planet. They are distributed in all parts of the world, except for the interior of Antarctica, deep ocean trenches and air space.

Findings site

1. Most birds are adapted to fly, unlike most animals. Only birds have wings.
2. Birds are oviparous, animals are viviparous, except for the first animals.
3. Birds are covered with feathers, animals are covered with wool.
4. The number of bird species prevails over the number of mammal species.
5. Unlike birds, mammals feed their young with milk produced by the mammary glands of females.
6. Birds lack teeth, while animals have them and are highly differentiated.
7. Birds have four sections of the spine, while mammals have five.
8. The respiratory system of birds has lungs and a lung sac, allowing for "double breathing". In mammals, breathing is carried out by the lungs with the bronchi using the diaphragm.
9. The pulse rate of a bird exceeds the pulse rate of a mammal, but only in mammals, non-nuclear erythrocytes “work” in the blood.
10. In addition to those systems that contribute to flight, birds have a lower level of organization of the organ systems than mammals.

How are birds different from mammals?

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Birds and mammals have common roots - the Reptile class, but due to a number of morphological and anatomical differences, these animals were able to master different living spaces.

Who are birds and mammals

Comparison of birds and mammals

The difference between birds and mammals

Who are birds and mammals

Birds is a biological taxon, a class. They belong to the type of Chordata, the Animal Kingdom. A crow, a chicken, a sparrow, a penguin, or a peacock can be named as a typical representative of the class.

mammals is a biological taxon. Class Mammals belong to the phylum Chordata, the Animal Kingdom. Typical representatives of the class are hares, lions, cows, dolphins and walruses.

Comparison of birds and mammals

What is the difference between birds and mammals? Birds have a number of characteristic features that allowed them to be combined into one taxon. These are vertebrates like fish and quadrupeds. They are warm-blooded like mammals and oviparous like reptiles. A unique feature of these animals is the adaptation of the body to flight: it is covered with feathers, the upper limbs are modified into wings. A separate "pride" of birds is the beak, which no other species of Chordates has.

Martin. bird class

All mammals have a number of features that made it possible to distinguish them into one class. A little “lagging behind” in certain indicators from their colleagues are the first animals - platypuses and echidnas. But if every time you do not return to echidnas and platypuses, then all mammals are warm-blooded. Just like the birds. Most mammals are covered with hair or hair. They are engaged in live birth and feed their young with milk with the help of modified sweat glands.

The anatomical structure of birds is adapted to their ability to fly. Even those birds that do not fly today once had this skill. Or rather, not they, but their distant ancestors. The anatomical structure of a mammal depends on the environment in which it resides.

The skeleton of birds is simplified, strengthened and lightened. The bones of the skull are fused. They do not have prominent cranial sutures. There are four divisions in the spine, three of which are fused. The neck of birds is long and mobile. The girdle of the forelimbs changed into wings, while the reduction and fusion of some of them took place. Only birds have a keel attached to the ribs.

The skeleton of a mammal is represented by five sections (only cetaceans do not have a sacral). The skull of these animals is large, its bones have grown together, forming protection for the developed brain. More details: http :// thedifference . en / chem - otlichayutsya - pticy - ot - mlekopitayushhix /

Due to the fact that they spend a significant part of their lives in the air, some features have appeared in birds. Their hollow bones are filled with air, which allows them to lighten their body weight. In flying species, the sternum is well developed - the keel, to which powerful muscles are attached. These are warm-blooded animals with an intensive metabolism. Body temperature reaches 42 ° C. The respiratory system, in addition to well-developed cellular lungs, is also represented by air sacs that allow the lungs to be ventilated during inhalation and exhalation (double breathing). When you inhale, air enters the lungs and lung sacs. When exhaling, the wings descend, squeezing the bags, and the air again passes through the lungs. This contributes to better absorption of oxygen and a high metabolism. Birds have a four-chambered heart. Arterial and venous blood are completely separated. The digestive, excretory and reproductive systems of birds and reptiles are similar. Birds lack teeth, a bladder, and females have a second ovary and oviduct, which is associated with adaptation to flight.

Birds swallow food whole and enter the goiter through the long esophagus, where it is previously exposed to digestive juices. The stomach consists of two sections: glandular and muscular. Due to the large number of small stones swallowed with food, food is rubbed in the muscular section. The nervous system of birds is much better developed than that of reptiles, especially the forebrain and cerebellum. Therefore, the behavior of birds is more complicated, they develop many conditioned reflexes.

Fertilization in birds is internal. The female lays eggs in built nests. They are characterized by incubation of eggs and care for offspring.

Birds are divided intobrood and nest (chicks). In brood birds, chicks hatch more adapted to life: they are sighted, covered with down, able to move and eat on their own. These are chickens, ducks, geese, black grouse. They usually build their nests on the ground.

In nesting birds, the chicks hatch helpless and blind, their body is not lowered, they are fed by their parents. These are crows, doves, starlings, woodpeckers, eagles, hawks and many others. They nest high in trees, in hollows, in burrows along the banks of rivers (swallows), on rocks, in hard-to-reach places.

According to the way birds are fed, they are divided intoherbivores (goldfinches, siskins, crossbills, thrushes),insectivores(woodpeckers, nuthatches, tits),predatory(falcons, hawks, eagles, owls). In addition, many aquatic birds feed on fish (ducks, penguins, herons, pelicans). There are birds andscavengers,which feed on the carcasses of animals, such as vultures.

All birds are combined into three large groups: keelless, swimming (penguins) and keel-chested.

2. Varieties of birds.

keelless, or running, birds live in Africa, Australia, South America. This is the most primitive group: their sternum is flat, there is no keel, wings are poorly developed. These include African and American ostriches, emus and cassowaries that inhabit Australia. These are rather large birds, good runners, reaching a height 2.5 m . Emus and cassowaries have even more underdeveloped wings than ostriches, but have well-developed strong legs. The smallest ratite birds are kiwi, inhabiting the forests of New Zealand (height up to 55 cm ). Their wings are greatly reduced, they have practically disappeared, their legs are widely spaced, so they move slowly. In ratites, the eggs are usually incubated by the male.

penguins - also flightless birds, but they have a keel on the sternum. The largest species - the emperor penguin reaches a height 1m . All penguins are excellent swimmers, their wings have turned into flippers, they “fly” under water, flapping their wings and steering their legs, like other birds in the air, and on land they move clumsily, waddling. Their feathers fit snugly together, well lubricated with oil from the coccygeal gland, which prevents them from getting wet.livepenguins on the coast of Antarctica, feed on fish, mollusks, crustaceans. They nest on the ground. The males incubate the eggs by holding them between their paws and lower abdomen. Females at this time feed in the sea. By the end of the development period before hatching, they return, nurse and feed the chicks.

keel-breasted — the most common group of birds. They are divided into 34 squads. Most of them are flying. Depending on the habitat and nutrition, they can be divided into the following ecological groups: forest, steppe-desert, swamp-meadow, water, landscape gardening, predatory.

Forestbirds nest and feed in the forest, both in the trees and in the lower tier, on the ground. These are woodpeckers, goldfinches, siskins, finches, finches, birds of paradise living in Australia. As well as black grouse, capercaillie, partridges, pheasants living in forest clearings, edges.

To marsh-meadowbirds include cranes, storks, waders, corncrakes, herons. The birds of this group have long legs and feed on small animals. Birds of open spaces include larks, soaring high in the sky. But they nest and feed on insects on the ground.

Steppe-desert birds are usually good runners. Along with ostriches, these are bustards, runners.

To the group waterunite those birds, most of whose life takes place on the water. These are gulls, ducks, geese, pelicans, swans, etc. They feed mainly on fish.

Predatorybirds live everywhere, divided into day and night predators. Diurnal predators are hawks, falcons, eagles, buzzards, sea eagles, gyrfalcons, kestrels, and vultures. Night predators include owls and eagle owls.

Birds of great economic importance are chickens, ducks, geese, turkeys. Many of them serve as an object of fishing and hunting. Birds are of great benefit, destroying insect pests, especially during the feeding of chicks.

3. Mammals. General characteristics.

mammals - This is the most highly organized class of vertebrates. They are characterized by a highly developed nervous system (due to an increase in the volume of the cerebral hemispheres and the formation of the cortex); relatively constant body temperature; four-chambered heart; the presence of a diaphragm - a muscular partition separating the abdominal and chest cavities; development of cubs in the mother's body and breastfeeding. The body of mammals is often covered with hair. The mammary glands appear as modified sweat glands. The teeth of mammals are peculiar. They are differentiated, their number, form and function differ significantly in different groups and serve as a systematic feature.

The body is divided into head, neck and torso. Many have a tail. Animals have the most perfect skeleton, the basis of which is the spinal column. It is subdivided into 7 cervical, 12 thoracic, 6 lumbar, 3-4 sacral fused and caudal vertebrae, the number of the latter is different. Mammals have well-developed sense organs: smell, touch, sight, hearing. There is an auricle. The eyes are protected by two eyelids with eyelashes.

With the exception of oviparous, all mammals carry their young inuterus -special muscle organ. Cubs are born alive and fed with milk. The offspring of mammals are more in need of further care than those of other animals.

All of these features allowed mammals to gain a dominant position in the animal kingdom. They are found all over the globe.

The appearance of mammals is very diverse and is determined by the habitat: aquatic animals have a streamlined body shape, flippers or fins; land dwellers - well-developed limbs, dense body. In the inhabitants of the air environment, the front pair of limbs is transformed into wings. A highly developed nervous system allows mammals to better adapt to environmental conditions, contributes to the development of numerous conditioned reflexes.

The mammalian class is divided into three subclasses: oviparous, marsupials, and placentals.

oviparous, or perverse are the most primitive mammals. Unlike other representatives of this class, they lay eggs, but they feed their young with milk. They have keptcloaca -part of the intestine, where three systems open - digestive, excretory and reproductive. Therefore, they are also called single pass. In other animals, these systems are separated. Oviparous are found only in Australia. These include only four species: echidnas (three species) and platypus.

marsupials mammals are more highly organized, but they are also characterized by primitive features. They give birth to live, but underdeveloped cubs, practically embryos. These tiny cubs crawl into the pouch on the mother's belly, where, feeding on her milk, they complete their development.

Kangaroos, marsupial mice, squirrels, anteaters (nambats), marsupial bears (koala), badgers (wombats) live in Australia. The most primitive marsupials live in Central and South America. This is an opossum, a marsupial wolf.

Placental animals are well developedplacenta- an organ that attaches to the wall of the uterus and performs the function of exchanging nutrients and oxygen between the mother's body and the embryo.

Placental mammals are divided into 16 orders. These include insectivores, bats, rodents, lagomorphs, carnivores, pinnipeds, cetaceans, ungulates, proboscis, primates.

Insectivoresmammals, which include moles, shrews, hedgehogs, etc., are considered the most primitive among placental. They are quite small animals. The number of teeth they have is from 26 to 44, the teeth are undifferentiated.

Bats -the only flying animals among animals. They are mainly crepuscular and nocturnal animals that feed on insects. These include fruit bats, bats, evenings, vampires. Vampires are bloodsuckers, they feed on the blood of other animals. Bats have echolocation. Although their eyesight is poor, due to their well-developed hearing, they pick up the echo from their own squeak, reflected from objects,

Rodents -the most numerous detachment among mammals (about 40% all kinds of animals). These are rats, mice, squirrels, ground squirrels, marmots, beavers, hamsters, and many others. A characteristic feature of rodents are well-developed incisors. They do not have roots, grow all their lives, grind down, there are no fangs. All rodents are herbivores.

Close to rodents detachmentlagomorphs..They have a similar structure of teeth, and also eat plant foods. These include hares and rabbits.predatorybelongs to more than 240 species of animals. Their incisors are poorly developed, but they have powerful fangs and predatory teeth that serve to tear apart the meat of animals. Predators feed on animal and mixed food. The detachment is divided into several families: canine (dog, wolf, fox), bear (polar bear, brown bear), cat (cat, tiger, lynx, lion, cheetah, panther), marten (marten, mink, sable, ferret) and etc. Some predators are characterized by hibernation (bears).

pinnipedsare also carnivores. They have adapted to life in the water and have specific features: the body is streamlined, the limbs are turned into flippers. The teeth are poorly developed, with the exception of the fangs, so they only grab food and swallow it without chewing. They are excellent swimmers and divers. They feed mainly on fish. They breed on land, along the shores of the seas or on ice floes. The order includes seals, walruses, fur seals, sea lions, etc.

To the squad cetaceansthe inhabitants of the waters also belong, but unlike the pinnipeds, they never go to land and give birth to cubs in the water. Their limbs have turned into fins, and in the shape of the body they resemble fish. These animals have mastered the water for the second time, and in connection with this they have many features characteristic of aquatic inhabitants. However, the main features of the class have been preserved. They breathe atmospheric oxygen through their lungs. Cetaceans include whales and dolphins. The blue whale is the largest of all modern animals (length 30 m, weight up to 150 tons).

Ungulates are divided into two orders. Toequids include horses, tapirs, rhinos, zebras, donkeys. Their hooves are modified middle fingers, the remaining fingers are reduced to varying degrees in different species. Ungulates have well-developed molars, as they feed on plant foods, chewing and grinding it.

At artiodactylsthe third and fourth fingers are well developed, turned into hooves, which account for the entire body weight. These are giraffes, deer, cows, goats, sheep. Many of them are ruminants and have a complex stomach.

To the squad proboscisbelong to the largest of land animals - elephants. They live only in Africa and Asia. The trunk is an elongated nose, fused with the upper lip. Elephants do not have fangs, but powerful incisors have turned into tusks. In addition, they have well-developed molars that grind plant food. These teeth change in elephants 6 times during their lives. Elephants are very voracious. One elephant can eat up to 200 kg of hay.

Primatescombine up to 190 species. All representatives are characterized by a five-fingered limb, grasping hands, nails instead of claws. The eyes are directed forward (primates have developed binocular vision). These are inhabitants of tropical and subtropical forests, leading both arboreal and terrestrial lifestyles. They feed on plant and animal food. The dental apparatus is more complete and differentiated into incisors, canines, molars.

There are two groups: semi-monkeys and monkeys. Semi-monkeys include lemurs, lorises, tarsiers. Monkeys are divided into broad-nosed (marmosets, howler monkeys, coet) and narrow-nosed (macaques, monkeys, baboons, hamadryas). The group of higher narrow-nosed great apes includes the gibbon, chimpanzee, gorilla, and orangutan. Humans also belong to primates.

Birds, like mammals, belong to the class of animals, but despite this unifying feature, birds have a number of abilities and characteristics that significantly distinguish them from mammals.

For many, the most obvious difference comes to mind - feathers and wings. Yes it is. Plumage is characteristic only for birds, otherwise they would not be able to make their flights. Birds are vertebrates, and this unites them with mammals, fish, reptiles, allowing them to be included in the vast biological kingdom - Animals.

Birds descended from reptiles, and they owe this to their distant parent - lizards. The first bird-like creature was the bird Archeopteryx. She lived about 120 million years ago and looked like a pangolin, the size of a dove, which moved on its hind limbs, had wings, but could not fly. She also had a beak, feathers, seated teeth, but a long, twenty-vertebral tail from a lizard.


Flights were gliding and difficult for Archeopteryx, but he had long sharp claws, with which the lizard easily climbed trees and made short flights. Following from this, it can be said with certainty that the progenitor of modern birds was half lizard half bird, so the relationship of these two classes of animals is obvious.

Who are animals and who are birds

Animals are living organisms united in one large kingdom. About 34 types of animals go to this kingdom, which in turn are divided into 50 million species of living beings.

Birds are the same animals, but the body of which is not covered with wool, but with feathers. The forelimbs of birds were modified into wings, which gave them the ability to fly. In total, there are about 10,000 species of various birds.

Comparative characteristics of animals and birds

If birds and animals belong to the same biological kingdom, then the question of their differences arises. What is the difference between these representatives of the animal kingdom?

It must be said that all birds are warm-blooded animals who can fly. This extraordinary ability determined and shaped the morphological and physiological characteristics of birds, and also adapted their body for flight. As a result of a long evolution, the forelimbs of birds were transformed into wings, and the legs became more massive and muscular. Massive legs are needed for a successful takeoff and landing, and the tail serves as a directional controller.

Animals, unlike birds, can be either warm-blooded (mammals) or cold-blooded (reptiles, fish, amphibians). Some types of animals have no shelter at all (flatworms, tunicates, sponges).

The body of a bird, unlike an animal, is covered feathers. The plumage allows you to create a greater streamlining of the body during flight, and at low temperatures the feather better retains the heat of the small body of the bird. The body of the animal, in turn, has the most diverse coverage. It can be the epidermis, scales, chitinous cut, shell, skin, or just a woolen cover.

Bird bones are incredibly strong despite their lightness compared to animal bones. In the process of flight, the unity and immobility of the body is of great importance. It is provided by the fusion of the vertebrae of all parts of the bird's spine, with the exception of the cervical. Birds, in comparison with animals, have a rather long and elongated neck, and also have a keel. Many types of animals, not including chordates, do not have an internal skeleton at all.


The bird's digestive system begins with the beak, which animals don't have. The metabolism is accelerated, which is required in order for the food to be quickly processed, while providing the bird with the necessary amount of free energy expended for flight. The circulatory, respiratory, excretory systems work in an accelerated mode.

Describe animal husbandry, indicate its main branches.

animal husbandry- the second most important (after crop production) branch of agriculture in Russia. The well-being of the country as a whole largely depends on how well it is developed. Until recently, animal husbandry in Russia was considered unprofitable. Today, thanks to the introduction of new technologies into production, the situation has changed significantly for the better. Animal husbandry is divided into several important branches and types.

Branches There are many agricultural breeds. Almost each of them has its own branches of animal husbandry. The most significant in our country are: Pig breeding. The main products of this livestock sector are meat and lard. Horse breeding. Of great importance for the national economy is both pedigree breeding of horses, and productive, as well as sports. Cattle breeding. Cattle breeding is currently the main branch of animal husbandry. After all, the degree of provision of the population with basic food products, such as milk and meat, depends on how developed this area will be. Raising small cattle is also very important. From this direction of animal husbandry, such areas of the national economy as food (meat, milk) and light industry (woolen clothing and household items) are directly dependent. Poultry farming. This industry is responsible for providing the population with important food items such as eggs, meat, down and feathers. Fur farming. Breeding nutrias, minks, arctic foxes, etc. allows you to get skins for sewing outerwear, hats, accessories and other things. Beekeeping. Honey, wax, royal jelly are also more than necessary products. These are the main branches of animal husbandry. In addition to them, reindeer breeding, fish farming, and camel breeding are also developed in our country.

37. When studying the Earth

and its individual parts, geoimages are used - space-time models of the earth's surface. The need to determine the location of objects on Earth gave rise to the compilation of maps and plans, the appearance of globes with their special, symbolic language, the production of aerial photographs and satellite images. A variety of geo-images allow you to look at the earth's surface from above and present the relative position of natural and anthropogenic objects.

A three-dimensional cartographic model of the Earth is a globe, which helps to represent the position of the planet in space. The first globe was made by the Flemish cartographer Gerardus Mercator in 1490. A geographic globe (from Latin globe - a ball) is a reduced model of the Earth, reflecting its spherical shape. The advantages of the globe are visibility, the absence of distortions in the cartographic image, the possibility of demonstrating the axial rotation of the Earth.

1. Similarities and differences between the plan and the geographical map. First, let's find out the similarity of the terrain plan with a geographical map. It is known that both the plan and the map are a reduced schematic representation of the Earth's surface on paper (a plane).

On them, the objects of the earth's surface are reduced in scale. Conventional signs are used instead of their specific forms. Along with such general similar features, there are noticeable differences between the plan and the geographical map. The main ones are the following:

1) scale difference. The plan is drawn on a large scale: 1 cm-5 m, 1 cm-10 m, etc. Due to the large scale, objects on the earth's surface are shown in great detail on the plan. On it you can distinguish individual quarters of the settlement, houses, schools, a mosque, a palace of culture, etc. You can draw a plan of the school yard and even, if you like, a plan of your room.
A geographical map covers large areas - a region, a state, a mainland, even the entire globe. Therefore, it is drawn on a small scale. On it, the surface of the Earth is reduced by several million times. In terms of completeness and accuracy of the image, only topographic maps are close to plans;
2) regardless of the size of the covered area Meridians and parallels are necessarily depicted on the map(remember how they look in different maps). The meridians show the north-south direction, the parallels show the west-east direction. There are no such lines on the plan. The top of the plan corresponds to the north, the bottom to the south, the left to the west, and the right to the east;
3) the plan covers small plots of land. Therefore, it does not take into account the bulge of the globe and it is assumed that the earth is flat. Measurement work can be carried out on any part of the plan. The map covers large areas or even the entire globe, therefore, the sphericity of the Earth's shape is taken into account here. And depending on the size of the depicted territory, the degree of map distortion increases (remember the distortions on the world map and the map of the hemispheres);
4) difference in conventions. If on the plan it is possible to determine the exact dimensions of many objects using conventional signs (the length of the road and river, the area of ​​\u200b\u200bthe lake or garden, etc.), then on the map this is impossible. For example, on the plan it is easy to determine the shape of the settlement, the direction of the streets, etc. On the map, only their location is marked.

The soil

This is a special natural body, formed on the surface of the Earth, as a result of the interaction of living (organic) and dead (inorganic) nature. The most important property of soil, which distinguishes it from rocks, is fertility. It is due to the presence of humus or humus in the soils.

The main types of soils in Russia:

1. Tundra gley soils are located on the plains. Formed without much influence of vegetation on them. These soils are found in areas where there is permafrost (in the Northern Hemisphere). Often, gley soils are places where deer live and feed in summer and winter. Chukotka can serve as an example of tundra soils in Russia. In areas with such soils, people are engaged in agriculture. Potatoes, vegetables and various herbs grow on such land.

2.Arctic soils are obtained as a result of thawing permafrost. This soil is quite thin. The maximum layer of humus (fertile layer) is 1-2 cm. This type of soil has a low acidic environment. This soil is not restored due to the harsh climate. These soils are common in Russia only in the Arctic (on a number of islands in the Arctic Ocean). Due to the harsh climate and a small layer of humus, nothing grows on such soils.

3. Podzolic soils are common in forests. There is only 1-4% humus in the soil. Podzolic soils are obtained through the process of podzol formation. There is a reaction with an acid. That is why this type of soil is also called acidic. In Russia, podzolic soils are common in Siberia and the Far East.

Soddy-podzolic soils are a subtype of podzolic soils. They are similar in composition to podzolic soils. A characteristic feature of these soils is that they can be more slowly washed out by water, unlike podzolic ones. Soddy-podzolic soils are found mainly in the taiga (territory of Siberia). This soil contains up to 10% of the fertile layer on the surface, and at a depth the layer sharply decreases to 0.5%.

Permafrost-taiga soils were formed in forests, in permafrost conditions. They are found only in continental climates. The greatest depths of these soils do not exceed 1 meter. This is caused by proximity to the permafrost surface. The humus content is only 3-10%.

4. Gray forest soils are formed on the territory of forests. An indispensable condition for the formation of such soils is the presence of a continental climate. Deciduous forests and herbaceous vegetation. Places of formation contain the element necessary for such soil - calcium. Thanks to this element, water does not penetrate deep into the soil and does not erode them. These soils are grey. The content of humus in gray forest soils is 2-8 percent, that is, soil fertility is average.

light gray

Dark grey. (These soils prevail in Russia in the territory from Transbaikalia to the Carpathian Mountains. Fruit and grain crops are grown on soils

5. Brown forest soils are common in forests: mixed, coniferous and broad-leaved. These soils are found only in temperate warm climates. Soil color brown. Usually brown soils look like this: on the surface of the earth there is a layer of fallen leaves, about 5 cm high. Next comes the fertile layer, which is 20, and sometimes 30 cm. Even lower is a clay layer of 15-40 cm. There are several subtypes of brown soils. The subtypes vary with temperatures. There are: typical, podzolized, gley (surface gley and pseudopodzolic). On the territory of the Russian Federation, soils are common in the Far East and near the foothills of the Caucasus. Undemanding crops such as tea, grapes and tobacco are grown on these soils. Forest grows well on such soils.

6. Chestnut soils are common in steppes and semi-deserts. The fertile layer of such soils is 1.5-4.5%. That says the average fertility of the soil. This soil has a chestnut, light chestnut and dark chestnut color. Accordingly, there are three subtypes of chestnut soil, differing in color.

On light chestnut soils, agriculture is possible only with abundant watering. The main purpose of this land is pasture.

Dark chestnut soils grow well without watering the following crops: wheat, barley, oats, sunflower, millet.