The earth's crust is the outermost solid shell of the earth. The main spheres of the planet Earth: lithosphere, hydrosphere, biosphere and atmosphere

Finally, a very sharp jump occurs at a depth of 2900 km. The part of the globe enclosed between the sole of the earth's crust, at a depth of 50-60 km, and a depth of 2900 km, is called the shell of the Earth. The part of the globe enclosed within the interface at a depth of more than 2900 km is called the core of the Earth, and the interface itself is called the boundary of the core.

The Earth's core consists of a substance that does not resist shape change, i.e. it behaves in relation to seismic vibrations like a liquid or gaseous body.

The upper cover of the globe, which composes the continents and the bed of the oceans, is divided into two main layers. The uppermost layer of the continental part of the earth's crust consists mainly of layers of so-called sedimentary rocks and rocks close in composition to granites. Therefore, the upper layer is usually called granite, although it must be remembered that this name is conditional, since this layer contains other rocks, and its composition may vary somewhat from region to region.

Below lies the so-called basalt layer. The main role in its structure is played by rocks rich in magnesium and iron and poor in silicic acid. These are varieties of the basalt group of rocks, and therefore the lower layer of the crust is called basalt. This layer is separated from the underlying rocks of the subcrustal layer by a surface clearly distinguishable by seismic waves. This surface is called the S. Mohorovicic surface, after the Yugoslav scientist who discovered it. The speed of seismic waves deeper than the interface immediately increases to 8 km/sec, which is due to an increase in the density of the Earth's matter.

The substance of the earth's crust is in a crystalline state. The thickness of the earth's crust is less under the oceans than under the continents. It is possible that under the bottom of the Pacific Ocean there is no granite layer at all.

The uppermost part of the earth's crust is largely composed of layered sedimentary rocks formed by the deposition of various small particles in the seas and oceans. The remains of animal organisms and plants that once inhabited the globe are buried in them. The total thickness of sedimentary rocks does not exceed 12-15 km. Their successive layers and the fossils of animals and plants contained in them allow geologists to restore the history of the development of life on Earth.

The upper part of the inner shell of the Earth is closest in chemical composition to the composition of rocks known as peridotites and pyroxenites, which are very rich in magnesium and iron and are distinguished by a significant specific gravity.

We have some evidence for the real existence of this subcrustal membrane. In the masses of rocks that fill the vertical diamond-bearing “pipes” of Kimberley in South Africa, as well as in the diamond mines of Yakutia, pieces of olivine and peridotite rocks brought from great depths are found in abundance. These are the deepest materials known to us that make up the Earth. But by the methods of modern geophysics, we know the Earth even further inland, though only in relation to the distribution of material in terms of density and elasticity, not yet knowing its other properties.

Thus, we can assume that the inner shell of the Earth extends to a depth of 2900 km. The substance of the shell is solid, but with plasticity, in the lower part it is devoid of a crystalline structure (amorphous). Its composition, apparently, is the same as in the uppermost (subcrustal) part. The change in the density of the Earth's shell is associated not so much with a change in composition as with pressure, which here reaches a huge value.

So, for example, the pressure per unit area is:

The Earth's core has the properties of a liquid. The radius of the earth's core is 3471 km. During the transition from the shell to the core, the physical properties of matter change dramatically. The reason for this change is probably the change in the atomic structure under the influence of high pressures, reaching about 3 million atmospheres. The temperature inside the Earth rises to 2000-3000 °, while the temperature rises most rapidly in the earth's crust, then much more slowly, and remains constant at great depths.

The Earth's density increases from 2.6 at the surface to 6.8 at the edge of the Earth's core. In the core itself, the density increases to 10, and in its central parts it exceeds 12.

Until recently, it was believed that the core has an iron composition similar to iron meteorites, and the shell has a silicate composition corresponding to stony meteorites. However, according to modern scientific views, the reason for the sharp jump in densities and a sharp decrease in hardness near the boundary of the Earth's core is not in the separation of matter according to chemical composition, but in the physicochemical process - the partial destruction of the electron shell of atoms at a critical pressure reaching 1.4 million atmospheres .

The detachment of electrons from nuclei under the influence of enormous pressure and high temperature facilitates a sharp compaction of the substance and gives it new properties, similar in terms of hardness to the properties of liquid bodies (the ability of liquid bodies, while maintaining volume, to change their original shape), and in terms of electrical conductivity - with the properties of metals . Therefore, such a transformation is called the transition of a substance into a metallic phase.

Thus, the conditions for the existence of matter in the great depths of the earth are sharply different from the conditions on the earth's surface and those that we can so far create by experiment.

Every year, the data of geophysics and astrophysics allow us to better and better understand the structure of the globe, and this, in turn, gives us the opportunity to see the connection between a number of important geological processes occurring in the earth's crust, with processes occurring in the depths of the globe.

That is why it is so important and so interesting to study the structure of our planet.

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Geography is the science of the internal and external structure of the Earth, studying the nature of all continents and oceans. The main object of study are various geospheres and geosystems.

Introduction

The geographic shell or GO is one of the basic concepts of geography as a science, introduced into circulation at the beginning of the 20th century. It denotes the shell of the entire Earth, a special natural system. The geographic shell of the Earth is called an integral and continuous shell, consisting of several parts that interact with each other, penetrate each other, constantly exchange substances and energy with each other.

Fig 1. Geographical shell of the Earth

There are similar terms, with narrow meanings, used in the writings of European scientists. But they do not designate a natural system, only a set of natural and social phenomena.

Stages of development

The geographic shell of the earth has gone through a number of specific stages in its development and formation:

geological (prebiogenic)– the first stage of formation, which began about 4.5 billion years ago (lasted about 3 billion years);
biological– the second stage, which began about 600 million years ago;
anthropogenic (modern)- a stage that continues to this day, which began about 40 thousand years ago, when humanity began to exert a noticeable influence on nature.

The composition of the geographic shell of the Earth

Geographic envelope- this is a system of the planet, which, as you know, has the shape of a ball, flattened on both sides by the caps of the poles, with a long equator of more than 40 tons km. GO has a certain structure. It consists of interconnected environments.

Upper and lower bounds

In the entire structure of the geographic envelope and geographic environments, a clear zoning can be traced.

The law of geographical zoning provides not only for the division of the entire shell into spheres and environments, but also for the division into natural zones of land and oceans. It is interesting that such a division naturally repeats itself in both hemispheres.

Zoning is due to the nature of the distribution of solar energy over latitudes and the intensity of moisture (different in different hemispheres, continents).

Naturally, it is possible to determine the upper boundary of the geographic envelope and the lower one. Upper bound located at an altitude of 25 km, and bottom line The geographic envelope runs at a level of 6 km under the oceans and at a level of 30-50 km on the continents. Although, it should be noted that the lower limit is conditional and there are still disputes over its setting.

Even if we take the upper boundary in the region of 25 km, and the lower one in the region of 50 km, then, compared to the total size of the Earth, we get something like a very thin film that covers the planet and protects it.

Basic laws and properties of the geographical shell

Within these boundaries of the geographical envelope, the basic laws and properties that characterize and determine it operate.

Interpenetration of components or intra-component movement- the main property (there are two types of intra-component movement of substances - horizontal and vertical; they do not contradict and do not interfere with each other, although in different structural parts of GO the speed of movement of components is different).
Geographic zonation- the basic Law.
Rhythm- the frequency of all natural phenomena (daily, annual).
The unity of all parts of the geographical shell due to their close relationship.

Characteristics of the Earth's shells included in the GO

Atmosphere

The atmosphere is important for keeping warm, and therefore life on the planet. It also protects all living things from ultraviolet radiation, affects soil formation and climate.

The size of this shell is from 8 km to 1 t km (or more) in height. It consists of:

gases (nitrogen, oxygen, argon, carbon dioxide, ozone, helium, hydrogen, inert gases);
dust;
water vapor.

The atmosphere, in turn, is divided into several interconnected layers. Their characteristics are presented in the table.

All shells of the earth are similar. For example, they contain all types of aggregate states of substances: solid, liquid, gaseous.

Fig 2. The structure of the atmosphere

Lithosphere

The hard shell of the earth, the earth's crust. It has several layers, which are characterized by different power, thickness, density, composition:

upper lithospheric layer;
sigmatic sheath;
semi-metallic or ore shell.

The maximum depth of the lithosphere is 2900 km.

What is the lithosphere made of? From solids: basalt, magnesium, cobalt, iron and others.

Hydrosphere

The hydrosphere is made up of all the waters of the Earth (oceans, seas, rivers, lakes, swamps, glaciers and even groundwater). It is located on the surface of the Earth and occupies more than 70% of the space. Interestingly, there is a theory according to which large reserves of water are contained in the thickness of the earth's crust.

There are two types of water: salt and fresh. As a result of interaction with the atmosphere, during condensate, the salt evaporates, thereby providing the land with fresh water.

Fig 3. Earth's hydrosphere (view of the oceans from space)

Biosphere

The biosphere is the most "living" shell of the earth. It includes the entire hydrosphere, the lower atmosphere, the land surface and the upper lithospheric layer. It is interesting that living organisms inhabiting the biosphere are responsible for the accumulation and distribution of solar energy, for the migration processes of chemicals in the soil, for gas exchange, and for redox reactions. We can say that the atmosphere exists only thanks to living organisms.

Fig 4. Components of the Earth's biosphere

Examples of the interaction of media (shells) of the Earth

There are many examples of media interaction.

During the evaporation of water from the surface of rivers, lakes, seas and oceans, water enters the atmosphere.
Air and water, penetrating through the soil into the depths of the lithosphere, makes it possible for vegetation to rise.
Vegetation provides photosynthesis by enriching the atmosphere with oxygen and absorbing carbon dioxide.
From the surface of the earth and oceans, the upper layers of the atmosphere are heated, forming a climate that provides life.
Living organisms, dying, form the soil.

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In the twentieth century, through numerous studies, mankind revealed the secret of the earth's interior, the structure of the earth in the context became known to every schoolchild. For those who do not yet know what the earth consists of, what are its main layers, their composition, what is the name of the thinnest part of the planet, we will list a number of significant facts.

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The shape and size of the planet Earth

Contrary to popular misconception our planet is not round. Its shape is called the geoid and is a slightly flattened ball. The places where the globe is compressed are called poles. The axis of the earth's rotation passes through the poles, our planet makes one revolution around it in 24 hours - an earth day.

In the middle, the planet is surrounded by an imaginary circle dividing the geoid into the Northern and Southern hemispheres.

Apart from the equator there are meridians - circles perpendicular to the equator and passing through both poles. One of them, passing through the Greenwich Observatory, is called zero - it serves as a reference point for geographic longitude and time zones.

The main characteristics of the globe include:

diameter (km.): equatorial - 12 756, polar (near the poles) - 12 713;
length (km.) of the equator - 40,057, meridian - 40,008.

So, our planet is a kind of ellipse - a geoid, rotating around its axis passing through two poles - North and South.

The central part of the geoid is surrounded by the equator - a circle dividing our planet into two hemispheres. In order to determine what the radius of the earth is, use half the values of its diameter at the poles and the equator.

And now about that what is the earth made of what shells it is covered with and what sectional structure of the earth.

Earth shells

Basic shells of the earth distinguished according to their content. Since our planet is spherical, its shells held together by gravity are called spheres. If you look at s trinity of the earth in a section, then three areas can be seen:

In order(starting from the surface of the planet) they are located as follows:

The lithosphere is a solid shell of the planet, including mineral layers of the earth.
Hydrosphere - contains water resources - rivers, lakes, seas and oceans.
Atmosphere - is a shell of air that surrounds the planet.

In addition, the biosphere is also distinguished, which includes all living organisms that inhabit other shells.

Important! Many scientists refer the population of the planet to a separate vast shell called the anthroposphere.

The earth's shells - the lithosphere, hydrosphere and atmosphere - are distinguished according to the principle of combining a homogeneous component. In the lithosphere - these are solid rocks, soil, the internal contents of the planet, in the hydrosphere - all of it, in the atmosphere - all the air and other gases.

Atmosphere

The atmosphere is a gaseous envelope its composition includes: , nitrogen, carbon dioxide, gas, dust.

Troposphere - the upper layer of the earth, containing most of the earth's air and extending from the surface to a height of 8-10 (at the poles) to 16-18 km (at the equator). Clouds and various air masses form in the troposphere.
The stratosphere is a layer in which the air content is much lower than in the troposphere. His average thickness is 39-40 km. This layer begins at the upper boundary of the troposphere and ends at an altitude of about 50 km.
The mesosphere is a layer of the atmosphere that extends from 50-60 to 80-90 km above the earth's surface. Characterized by a steady decrease in temperature.
Thermosphere - located 200-300 km from the surface of the planet, differs from the mesosphere by an increase in temperature as altitude increases.
Exosphere - starts from the upper boundary, lying below the thermosphere, and gradually passes into open space, it is characterized by low air content, high solar radiation.

Attention! In the stratosphere at an altitude of about 20-25 km there is a thin layer of ozone that protects all life on the planet from harmful ultraviolet rays. Without it, all living things would have perished very soon.

The atmosphere is the earth's shell, without which life on the planet would be impossible.

It contains the air necessary for the breathing of living organisms, determines suitable weather conditions, protects the planet from the negative impact of solar radiation.

The atmosphere consists of air, in turn, air is approximately 70% nitrogen, 21% oxygen, 0.4% carbon dioxide and other rare gases.

In addition, there is an important ozone layer in the atmosphere, at about 50 km altitude.

Hydrosphere

The hydrosphere is all the liquids on the planet.

This shell by location water resources and their degree of salinity includes:

the world ocean is a huge space occupied by salt water and includes four and 63 seas;
the surface waters of the continents are freshwater, as well as occasionally brackish water bodies. They are subdivided according to the degree of fluidity into reservoirs with a course - rivers on and reservoirs with stagnant water - lakes, ponds, swamps;
groundwater - fresh water below the earth's surface. Depth their occurrence varies from 1-2 to 100-200 and more meters.

Important! A huge amount of fresh water is currently in the form of ice - today in the permafrost zones in the form of glaciers, huge icebergs, permanent non-melting snow, there are about 34 million km3 of fresh water reserves.

The hydrosphere is primarily, a source of fresh drinking water, one of the main climate-forming factors. Water resources are used as means of communication and objects of tourism and recreation (leisure).

Lithosphere

The lithosphere is solid ( mineral) layers of the earth. The thickness of this shell ranges from 100 (under the seas) to 200 km (under the continents). The lithosphere includes the earth's crust and the upper part of the mantle.

What is located below the lithosphere is directly the internal structure of our planet.

The slabs of the lithosphere mainly consist of basalt, sand and clay, stone, and also the soil layer.

The scheme of the structure of the earth together with the lithosphere is represented by the following layers:

Earth's crust - upper, consisting of sedimentary, basalt, metamorphic rocks and fertile soil. Depending on the location, there are continental and oceanic crust;
mantle - located under the earth's crust. It weighs about 67% of the total mass of the planet. The thickness of this layer is about 3000 km. The upper layer of the mantle is viscous, lies at a depth of 50-80 km (under the oceans) and 200-300 km (under the continents). The lower layers are harder and denser. The composition of the mantle includes heavy iron and nickel materials. The processes occurring in the mantle determine many phenomena on the surface of the planet (seismic processes, volcanic eruptions, formation of deposits);
The central part of the earth is the core, consisting of an inner solid and an outer liquid part. The thickness of the outer part is about 2200 km, the inner one is 1300 km. Distance from surface d about the core of the earth is about 3000-6000 km. The temperature in the center of the planet is about 5000 Cº. According to many scientists, the nucleus land by composition is a heavy iron-nickel melt with an admixture of other elements similar in properties to iron.

Important! Among a narrow circle of scientists, in addition to the classical model with a semi-molten heavy core, there is also a theory that an inner luminary is located in the center of the planet, surrounded on all sides by an impressive layer of water. This theory, in addition to a small circle of adherents in the scientific community, has found wide circulation in science fiction literature. An example is the novel by V.A. Obruchev "Plutonia", which tells about the expedition of Russian scientists to the cavity inside the planet with its own small luminary and the world of animals and plants extinct on the surface.

Such a common earth structure map, including the earth's crust, mantle and core, every year more and more improved and refined.

Many parameters of the model with the improvement of research methods and the advent of new equipment will be updated more than once.

For example, in order to know exactly how many kilometers to outer part of the nucleus, it will take more years of scientific research.

At the moment, the deepest mine in the earth's crust, dug by man, is about 8 kilometers, so the study of the mantle, and even more so the core of the planet, is possible only in a theoretical context.

Layered structure of the Earth

We study what layers the Earth consists of inside

Conclusion

Having considered sectional structure of the earth we have seen how interesting and complex our planet is. The study of its structure in the future will help mankind to understand the mysteries of natural phenomena, will more accurately predict devastating natural disasters, and discover new, as yet undeveloped mineral deposits.

Life on our planet originated due to a combination of many factors. The Earth is at a favorable distance from the Sun - it does not heat up too much during the day and does not get supercooled at night. The earth has a solid surface and liquid water exists on it. The air envelope surrounding the Earth protects it from hard cosmic radiation and "bombardment" by meteorites. Our planet has unique features - its surface is encircled, interacting with each other, by several shells: solid, air and water.

Air shell - the atmosphere extends above the Earth to a height of 2-3 thousand km, but most of its mass is concentrated at the surface of the planet. The atmosphere is held together by the Earth's gravity, so its density decreases with altitude. The atmosphere contains oxygen, necessary for the respiration of living organisms. The atmosphere contains a layer of ozone, the so-called protective shield, which absorbs some of the sun's ultraviolet radiation and protects the Earth from excess ultraviolet rays. Not all planets in the solar system have a solid shell: for example, the surfaces of the giant planets - Jupiter, Saturn, Uranus and Neptune are composed of gases that are in a liquid or solid state due to high pressure and low temperatures. The solid shell of the Earth, or the lithosphere, is a huge mass of rocks on land and at the bottom of the ocean. Under the oceans and continents, it has a different thickness - from 70 to 250 km. The lithosphere is divided into large blocks - lithospheric plates.

The water shell of our planet - the hydrosphere includes all the water of the planet - in a solid, liquid and gaseous state. The hydrosphere is the seas and oceans, rivers and lakes, groundwater, swamps, glaciers, water vapor in the air and water in living organisms. The water shell redistributes the heat coming from the Sun. Slowly heating up, the water masses of the World Ocean accumulate heat, and then transfer it to the atmosphere, which softens the climate on the continents during cold periods. Involved in the world cycle, water is constantly moving: evaporating from the surfaces of the seas, oceans, lakes or rivers, it is transferred to land by clouds and falls in the form of rain or snow.

The shell of the Earth, in which life exists in all its manifestations, is called the biosphere. It includes the uppermost part of the lithosphere, the hydrosphere and the surface part of the atmosphere. The lower boundary of the biosphere is located in the earth's crust of the continents at a depth of 4-5 km, and in the air shell the sphere of life extends to the ozone layer.

All shells of the Earth influence each other. The main object of study of geography is the geographical shell - the planetary sphere, where the lower part of the atmosphere, the hydrosphere, the biosphere and the upper part of the lithosphere are intertwined and closely interact. The geographic shell develops according to daily and annual rhythms, it is influenced by eleven-year cycles of solar activity, therefore, a characteristic feature of the geographical shell is the rhythm of ongoing processes.

The geographic envelope changes from the equator to the poles and from the foothills to the tops of the mountains, it is characterized by the main patterns: integrity, unity of all components, continuity and heterogeneity.

The rapid development of human civilization has led to the appearance of a shell in which man actively influences nature. This shell is called the noosphere, or the sphere of the mind. Sometimes people change the surface of the planet even more actively than some natural processes. Gross intervention in nature, neglect of its laws can lead to the fact that over time the conditions on our planet will become unacceptable for life.

Anthropogenic impact on nature is currently penetrating into all spheres, so it is necessary to briefly consider the characteristics of the individual shells of the Earth.

The earth consists of the core, mantle, crust, lithosphere, hydrosphere and. Due to the impact of living matter and human activity, two more shells arose - the biosphere and the noosphere, including the technosphere. Human activity extends to the hydrosphere, lithosphere, biosphere and noosphere. Let us briefly consider these shells and the nature of the impact of human activity on them.

General characteristics of the atmosphere

The outer gaseous shell of the Earth. The lower part is in contact with the lithosphere or, and the upper part is in contact with interplanetary space. consists of three parts:

1. Troposphere (lower part) and its height above the surface is 15 km. The troposphere consists of , the density of which decreases with height. The upper part of the troposphere is in contact with the ozone screen - an ozone layer 7-8 km thick.

The ozone shield prevents hard ultraviolet radiation or high-energy cosmic radiation from reaching the Earth's surface (lithosphere, hydrosphere), which are detrimental to all living things. The lower layers of the troposphere - up to 5 km from sea level - are an air habitat, while the lowest layers are most densely populated - up to 100 m from the land surface or. The greatest impact from human activity, which has the greatest ecological significance, is experienced by the troposphere and especially its lower layers.

2. Stratosphere - the middle layer, the limit of which is a height of 100 km above sea level. The stratosphere is filled with rarefied gas (nitrogen, hydrogen, helium, etc.). It goes into the ionosphere.

3. Ionosphere - the upper layer, passing into interplanetary space. The ionosphere is filled with particles arising from the decay of molecules - ions, electrons, etc. In the lower part of the ionosphere, the "northern lights" appear, which is observed in areas beyond the Arctic Circle.

In ecological terms, the troposphere is of the greatest importance.

Brief description of the lithosphere and hydrosphere

The surface of the Earth, located under the troposphere, is heterogeneous - part of it is occupied by water, which forms the hydrosphere, and part is land, which forms the lithosphere.

Lithosphere - the outer hard shell of the globe, formed by rocks (hence the name - "cast" - stone). It consists of two layers - the upper, formed by sedimentary rocks with granite, and the lower, formed by solid basalt rocks. Part of the lithosphere is occupied by water (), and part is land, making up about 30% of the earth's surface. The topmost layer of land (for the most part) is covered with a thin layer of fertile surface - soil. The soil is one of the environments of life, and the lithosphere is the substrate on which various organisms live.

Hydrosphere - the water shell of the earth's surface, formed by the totality of all water bodies on Earth. The thickness of the hydrosphere is different in different areas, but the average depth of the ocean is 3.8 km, and in some depressions - up to 11 km. The hydrosphere is a source of water for all organisms living on Earth, it is a powerful geological force that cycles water and other substances, the "cradle of life" and the habitat of aquatic organisms. The anthropogenic impact on the hydrosphere is also great and will be discussed below.

General characteristics of the biosphere and noosphere

Since the appearance of life on Earth, a new, specific shell has arisen - the biosphere. The term "biosphere" was introduced by E. Suess (1875).

The biosphere (sphere of life) is that part of the shells of the Earth in which various organisms live. The biosphere occupies a part (the lower part of the troposphere), the lithosphere (the upper part, including the soil) and permeates the entire hydrosphere and the upper part of the bottom surface.

The biosphere can also be defined as a geological shell inhabited by living organisms.

The boundaries of the biosphere are determined by the presence of conditions necessary for the normal functioning of organisms. The upper part of the biosphere is limited by the intensity of ultraviolet radiation, and the lower part by high temperature (up to 100°C). Bacterial spores are found at an altitude of 20 km above sea level, and anaerobic bacteria are found at a depth of up to 3 km from the earth's surface.

It is known that they are formed by living matter. The density of the biosphere is characterized by the concentration of living matter. It has been established that the highest density of the biosphere is characteristic of the land and ocean surfaces at the interface between the lithosphere and hydrosphere and the atmosphere. The density of life in the soil is very high.

The mass of living matter in comparison with the mass of the earth's crust and hydrosphere is small, but plays a huge role in the processes of change in the earth's crust.

The biosphere is the totality of all biogeocenoses on Earth, therefore it is considered the highest ecosystem of the Earth. Everything in the biosphere is interconnected and interdependent. The gene pool of all organisms on the Earth ensures the relative stability and renewability of the biological resources of the planet, if there is no sharp interference in natural ecological processes by various forces of a geological or interplanetary nature. At present, as mentioned above, anthropogenic factors affecting the biosphere have taken on the character of a geological force, which must be taken into account by humanity if it wants to survive on Earth.

Since the appearance of man on Earth, anthropogenic factors have arisen in nature, the effect of which is intensifying with the development of civilization, and a new specific shell of the Earth has arisen - the noosphere (the sphere of intelligent life). The term "noosphere" was first introduced by E. Leroy and T. Ya. de Chardin (1927), and in Russia for the first time in his works was used by V. I. Vernadsky (30-40s of the XX century). In the interpretation of the term "noosphere" there are two approaches:

1. "The noosphere is that part of the biosphere where human economic activity is carried out." The author of this concept was LN Gumilyov (son of the poetess A. Akhmatova and the poet N. Gumilyov). This point of view is correct if it is necessary to single out human activity in the biosphere, to show its difference from the activity of other organisms. Such a concept characterizes the "narrow sense" of the essence of the noosphere as the shell of the Earth.

2. "The noosphere is the biosphere, the development of which is directed by the human mind." This concept is widely represented in and is a concept in a broad understanding of the essence of the noosphere, since the influence of the human mind on the biosphere can be both positive and negative, the latter very often prevailing. The composition of the noosphere includes the technosphere - a part of the noosphere associated with the production activity of man.

At the present stage of the development of civilization and population, it is necessary to “reasonably” influence Nature, optimally influence it in order to bring minimal harm to natural ecological processes, restore destroyed or disturbed biogeocenoses, and even on human life as an integral part of the biosphere. Human activity inevitably makes changes to the world around, but, taking into account the possible consequences, anticipating possible negative impacts, it is necessary to make sure that these consequences are the least destructive.

Brief description of emergency situations that occur on the surface of the Earth, and their classification

An important role in natural ecological processes is played by emergencies that constantly arise on the surface of the Earth. They destroy local biogeocenoses, and, if repeated cyclically, in some cases they are environmental factors that contribute to the evolutionary processes.

Situations in which the normal functioning of a large number of people or the biogeocenosis as a whole becomes difficult or impossible are called emergency.

The concept of "emergencies" is more applicable to human activities, but it also applies to natural communities.

By origin, emergencies are divided into natural and anthropogenic (technogenic).

Natural emergencies arise as a result of natural phenomena. These include floods, earthquakes, landslides, mudflows, hurricanes, eruptions, etc. Consider some of the phenomena that cause natural emergencies.

This is a sudden release of the potential energy of the earth's interior, which takes the form of shock waves and elastic vibrations (seismic waves).

Earthquakes occur mainly due to underground volcanic phenomena, displacement of layers relative to each other, but they can also be man-made in nature and occur due to the collapse of mineral excavations. During earthquakes, displacements, vibrations and vibrations of rocks from seismic waves and tectonic movements of the earth's crust occur, which leads to the destruction of the surface - the appearance of cracks, faults, etc., as well as to the occurrence of fires, the destruction of buildings.

Landslides - sliding displacement of rocks down a slope from inclined surfaces (mountains, hills, sea terraces, etc.) under the influence of gravity.

During landslides, the surface is disturbed, biocenoses die, settlements are destroyed, etc. The greatest damage is caused by very deep landslides, the depth of which exceeds 20 meters.

Volcanism (volcanic eruptions) is a set of phenomena associated with the movement of magma (molten rock mass), hot gases and water vapor rising through channels or cracks in the earth's crust.

Volcanism is a typical natural phenomenon that causes great destruction of natural biogeocenoses, causing enormous damage to human economic activity, and heavily polluting the region adjacent to volcanoes. Volcanic eruptions are accompanied by other catastrophic natural phenomena - fires, landslides, floods, etc.

Mudflows are short-term stormy floods that carry a large amount of sand, pebbles, large rubble and stones, which have the character of mud-stone flows.

Mudflows are characteristic of mountainous regions and can cause significant damage to human activities, cause the death of various animals and cause the destruction of local plant communities.

Snow avalanches are called landslides of snow, entraining more and more masses of snow and other bulk materials. Avalanches are of both natural and anthropogenic origin. They cause great damage to human economic activity, destroying roads, power lines, causing death of people, animals and plant communities.

The above phenomena, which are the cause of emergencies, are closely related to the lithosphere. Natural phenomena that create emergency situations are also possible in the hydrosphere. These include floods and tsunamis.

Floods are the flooding of areas with water within river valleys, lake coasts, seas and oceans.

If floods are strictly periodic in nature (tides, ebbs), then in this case natural biogeocenoses are adapted to them as to a habitat under certain conditions. But often floods are unexpected and associated with individual non-periodic phenomena (excessive snowfall in winter creates conditions for the occurrence of extensive floods that cause flooding of a large area, etc.). During floods, soil covers are disturbed, the area may be contaminated with various wastes due to the erosion of their storage facilities, the death of animals, plants and people, the destruction of settlements, etc.

Gravitational waves of great strength arising on the surface of the seas and oceans.

Tsunamis have natural and man-made causes. Earthquakes, seaquakes and underwater volcanic eruptions are classified as natural causes, underwater nuclear explosions as man-made.

Tsunamis cause the death of ships and accidents on them, which in turn leads to pollution of the natural environment, for example, the destruction of an oil tanker will lead to pollution of a huge water surface with an oil film that is poisonous to plankton and pelargic forms of animals (plankton are suspended small organisms, living in the surface layer of the water of the ocean or other body of water; pelargic forms of animals - animals that freely move in the water column due to active movement, for example, sharks, whales, cephalopods; benthic forms of organisms - organisms leading a benthic lifestyle, for example, flounder, hermit crabs , echinoderms, algae attached to the bottom, etc.). Tsunamis cause strong mixing of waters, the transfer of organisms to an unusual habitat and death.

There are also phenomena that cause emergencies. These include hurricanes, tornadoes, various types of storms.

Hurricanes - tropical and extratropical cyclones, which have a greatly reduced pressure in the center, are accompanied by the occurrence of winds with high speed and destructive power.

There are weak, strong and extreme hurricanes that cause showers, sea waves and the destruction of land objects, the death of various organisms.

Vortex storms (squalls) are atmospheric phenomena associated with the occurrence of strong winds with great destructive power and a large area of distribution. There are snow, dust and dustless storms. Flurries cause the transfer of the upper layers of the soil, their destruction, the death of plants, animals, and the destruction of structures.

Tornadoes (tornadoes) are a vortex-like form of movement of air masses, accompanied by the appearance of air funnels.

The power of tornadoes is great, in the area of their movement there is a complete destruction of the soil, animals die, buildings are destroyed, objects are transferred from one place to another, causing damage to objects located there.

In addition to the natural phenomena described above, leading to emergency situations, there are other phenomena that cause them, the cause of which is human activity. Man-made emergencies include:

1. Transport accidents. When traffic rules are violated on various highways (roads, railways, rivers, seas), vehicles, people, animals, etc. die. Various substances enter the natural environment, including those that lead to the death of organisms of all kingdoms ( such as pesticides, etc.). As a result of accidents in transport, fires and ingress into gases (hydrogen chloride, ammonia, flammable and explosive substances) are possible.

2. Accidents at large enterprises. Violation of technological processes, non-compliance with the rules of operation of equipment, imperfection of technology can cause the release of harmful compounds into the environment, causing various diseases in humans and animals, contributing to the appearance of mutations in plant and animal organisms, as well as lead to destruction of buildings and fires. The most dangerous accidents at enterprises using. Accidents at nuclear power plants (NPPs) cause great harm, since in addition to the usual damaging factors (mechanical damage, single-acting release of harmful substances, fires), accidents at NPPs are characterized by damage to the area by radionuclides, penetrating radiation, and the damage radius in this case significantly exceeds the probability of occurrence accidents at other enterprises.

3. Fires covering large areas of forests or peatlands. As a rule, such fires are anthropogenic in nature due to violation of the rules for handling fire, but they can also be natural in nature, for example, due to lightning discharges (lightning). Such fires can also be caused by faults in power lines. Fires destroy natural communities of organisms over large areas, causing great economic damage to human economic activity.

All the described phenomena that violate natural biogeocenoses, causing great damage to human economic activity, require the development and adoption of measures to reduce their negative impact, which is implemented in the implementation of environmental actions and dealing with the consequences of emergency situations.

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