How space and in particular the planet Earth appeared is not known for certain. A huge number of scientists argue that life arose out of chaos (the Big Bang theory).
Although this theory is generally accepted, it proves absolutely nothing, like Darwin's theory of the origin of man, since there will be no empirical evidence.
How can something come out of chaos, if the entire universe and any biological system in particular - this is a strict order in everything.
The funniest thing here is that everything arose out of chaos according to academic science, but at the same time the Earth is at a favorable distance from the Sun and from this it naturally does not heat up too much during the day and does not overcool at night, even the slightest displacement and deviation in time of the Earth's rotation around the sun will lead to its death, or rather all living things on planet Earth.
Also, the Earth has a solid surface, and there is water in a liquid state on it. The air shell surrounding the Earth protects it from hard cosmic radiation and "bombardment" by meteorites. Doesn't even smell like chaos!

Planet Earth consists of 3 main shells:
1. Solid (Lithosphere)
2. Air (Atmosphere)
3. Water (Hydrosphere)

So let's consider in order all the shells of the Earth.

Lithosphere(from the Greek litos - stone and sphaira - ball) - the hard outer shell of the Earth or the earth's crust.

In the Lithosphere, there are:
- array rocks
- the earth's surface
- the soil.
The rock mass has different thickness- from 70 to 250 km and is divided into lithospheric plates.

More about soil:
The soil is the most fruitful, loose layer of the lithosphere. Most important property soil. The soil consists of substances, which, in turn, have all 3 states of aggregation (gas, liquid, solid state), as a result of the influence of various symbiotic microflora in the soil humus is formed, this is actually the fertile soil layer. The soil itself is constantly evolving and changing, as a result of which there is a wide variety of its types. As a result of the movement or transformation of matter, the soil is divided into separate layers, or horizons, the combination of which represents the soil profile. Over 50% mineral composition soils account for silica (Si02), about 1 - 25% - for alumina (Al2O3), 1 - 10% - for iron oxides (Fe2O3), 0.1 - 5% - for oxides of magnesium, potassium, phosphorus, calcium (Mg0 , K2O, P205, Ca0). Organic matter entering the soil with plant litter includes carbohydrates (lignin, cellulose, hemicellulose), proteins, fats, as well as the end products of metabolism in plants - wax, resins, tannins. Organic residues in the soil are destroyed (mineralized) with the formation of simpler (water, carbon dioxide, ammonia, etc.) substances or turn into more complex compounds - humus, or humus. One of the most important characteristics soil - its mechanical composition, i.e. particle content of different sizes.
Allocate the states of the mechanical composition:
1.sand
2. sandy loam
3.loam
4.clay.
By the way, it is on the mechanical composition of the soil that its water permeability, the ability to retain moisture, and the penetration of plant roots into it depend.
In addition, the soil is characterized by density, thermal and water properties. Great importance for the soil has aeration, this is the ability of the soil to be saturated with air Chemical properties Soils are highly dependent on the content of minerals, which are in the form of dissolved ions.
In lime, pH = 8,
In saline soils, pH = 4.

By the way, the following fact should be noted that not all planets have Solar system there is a hard shell: for example, the surfaces of the giant planets - Jupiter, Saturn, Uranus and Neptune consist of gases that are in a liquid or solid state due to high pressure and low temperatures... The Earth's hard shell, or lithosphere, is a huge mass of rocks on land and at the bottom of the ocean.

The atmosphere (from the Greek atmos - steam and sphaira - a ball) is the air gaseous envelope of the planet that surrounds the Earth and participates in its daily rotation.

The mass of the atmosphere is about 5.15 1015 tons. various forms life.
It extends to a height of 2-3 km, but its main concentration is closer to the surface of the Earth. Another important property of the atmosphere is the protection of the planet's biosphere from the radioactive ultraviolet rays of the sun; this property of the atmosphere becomes possible due to the presence of ozone in it.

The hydrosphere (from the Greek hydro - water and sphaira - ball) is the water shell of our planet.

The total volume of the Earth's hydrosphere is over 1 billion 500 million km3. Of these, in the oceans and seas - 1370 million km3, in underground waters - about 60 million km3 in the form of ice and snow - about 30 million km3, in inland waters- 0.75 million km3, and in the atmosphere - 0.015 million km3. Over 96% of the hydrosphere are seas and oceans; about 2% - groundwater, about 2% - glaciers, 0.02% - land waters (rivers, lakes, swamps).
It includes: oceans, seas, lakes, rivers, swamps, clouds, fogs and even dew.
The hydrosphere occupies 3/4 of the surface of the entire planet. Life on earth would also be impossible without the hydrosphere. the main component of the hydrosphere is water H2O
Water is the main source of life, because stores in itself all the information, in fact, being such a not hard, but a liquid disk, on which the basic information of the planet, including all living beings, is recorded. In addition to the fact that water is a carrier of information, all physical bodies living beings on the planet consume it in order to maintain the state of homeostasis inside the body, i.e. the constancy of the internal environment of the body, which is completely and completely subordinated to water-salt metabolism, which is the main one in the body of living beings.
Academic science claims that life on Earth originated from the presence of water on it, but this is an incorrect statement. It is worth mentioning that it is based on the support of modern tabulated science that life arose by chance as a result of chaos and the presence of water on the planet.
It would be more correct to say that life on the planet originated for a reason unknown to science. there is simply no explanation for the evidence for all of the above assumptions. Life arose not due to the presence, but already in the presence, i.e. most likely it was available as a necessary component, like all other conditions and was not anything supernatural, since in essence, the paradox of everything lies in the existence of life in general.
The water shell (hydrosphere) includes all the water of the planet - in solid, liquid and gaseous state.
Involved in the world circulation, water is constantly moving: evaporating from the surfaces of seas, oceans, lakes or rivers, it is transported by clouds to land and falls in the form of rain or snow, it redistributes the heat coming from the Sun. Slowly heating up, the water layers of the World Ocean accumulate heat, and then transfer it to the atmosphere, which softens the climate on the continents during cold periods.

We examined the 3 main shells of the planet, but at the same time it is worth highlighting 2 more shells, which essentially penetrate into the 3 main ones.

Biosphere (from the Greek. Bios - life) - the shell of the Earth, where life exists in all its manifestations, it penetrates into the lithosphere, hydrosphere and atmosphere.

The noosphere (from the Greek noos - mind) is the shell of interaction between nature and man.

You can write about the noosphere for a long time, but so far only one thing can be said; most of humanity does not have reason, which is evident in its attitude towards self-like (wars, colonization, slavery, class, strata of society), in relation to animals (destruction: hunting, use in food and much more.), in relation to nature (environmental pollution, excessive and improper use of its subsoil and minerals).
It should be noted that all shells interact closely with each other and, accordingly, affect each other. The basis for the study of geography is the planetary sphere, which, as it were, includes:
- the lower part of the atmosphere
- hydrosphere
- biosphere
- the upper part of the lithosphere
And remember the planet also exists according to strict cosmic laws, i.e. in the existence of our planet there is a huge code of laws, which in turn gives rise to order, and order is the basic law of life, in the absence of order, life, as a part of being, cannot exist. From this it is possible to draw a very simple, but at the same time very logical conclusion, if the very essence and basis of life is nothing more than order, so, accordingly, life can arise from only what it itself is. And chaos and randomness are complete contradictions and the opposite of the concept of life, in no way connected with it.

All life on Earth, the life of all living organisms from simple single-celled bacteria to complex biological species, the life of plants, animals and humans occurs in 3 important components: on the geographic surface of the Earth; in the aquatic environment of the planet's hydrosphere; and under the blue and white dome - the atmosphere of the Earth.

The main part of the surface the globe occupies the world ocean, where the continental and waterless parts account for less than 1/3 of the entire surface of the Earth. The surface of the earth consists of crust, its underwater part and the mainland, water part, as well as the atmosphere, which creates a blue dome that envelops the globe.

Interestingly, the Earth's atmosphere is important part of origin and maintenance of life on the planet, and is also the protective shell of the planet. The atmosphere forms the weather on the Earth, it regulates the water cycle in nature, the atmosphere protects the Earth from cosmic rays and raises the temperature of the Earth's surface, forming a "greenhouse effect".

In the twentieth century, through numerous studies, mankind revealed the secret of the earth's interior, the structure of the earth in a section became known to every schoolchild. For those who do not yet know what the earth is made 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.

In contact with

The shape and size of the planet Earth

Contrary to common misconception our planet is not round... Its shape is called a 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 - the earth's day.

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

Except for 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 geographical longitude and time zones.

The main characteristics of the globe include:

• diameter (km.): equatorial - 12 756, polar (at 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 is the radius of the earth, use half the values ​​of its diameter at the poles and the equator.

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

Earth shells

The main shell of the earth are allocated depending on their content. Since our planet has the shape of a ball, its shells, held by gravity, are called spheres. If you look at from tripping of the earth in a section, then three spheres can be seen:

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

1. The lithosphere is the hard shell of the planet, including mineral layers of the earth.
2. Hydrosphere - contains water resources - rivers, lakes, seas and oceans.
3. Atmosphere - is an air shell that surrounds the planet.

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

Important! Many scientists attribute the population of the planet to a separate vast envelope 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, it is hard rocks, soil, the inner contents of the planet, in the hydrosphere - all of it, in the atmosphere - all the air and other gases.

Atmosphere

Atmosphere - gas shell, v it includes:, nitrogen, carbon dioxide, gas, dust.

1. Troposphere - the top 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 are formed in the troposphere.
2. 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 from the upper boundary of the troposphere and ends at an altitude of about 50 km.
3. The mesosphere is a layer of the atmosphere that extends from 50-60 to 80-90 km above the earth's surface. It is characterized by a steady drop in temperature.
4. Thermosphere - located 200-300 km from the surface of the planet, differs from the mesosphere by an increase in temperature with increasing altitude.
5. Exosphere - starts from the upper border, which lies below the thermosphere, and gradually turns into open space, it is characterized by a 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, which protects all life on the planet from ultraviolet rays, which are destructive for it. Without it, all living things would very soon perish.

Atmosphere - earthly shell, without which life on the planet would be impossible.

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

The atmosphere consists of air, while 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.

Hydrosphere

The hydrosphere is all fluids on the planet.

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

• the world ocean - a huge area 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 current - rivers on and reservoirs with stagnant water - lakes, ponds, swamps;
• groundwater - fresh water located below the earth's surface. Depth their occurrence ranges from 1-2 to 100-200 meters or more.

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, constant non-melting snow, there are about 34 million km3 of fresh water reserves.

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

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 internal structure our planet.

The plates of the lithosphere are predominantly composed of basalt, sand and clay, stone, and soil.

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, continental and oceanic crust are distinguished;
• mantle - is located under the earth's crust. 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 mantle contains heavy ferruginous and nickel materials. The processes occurring in the mantle are responsible for many phenomena on the planet's surface (seismic processes, volcanic eruptions, the formation of deposits);
• The central part of the land is a core consisting of an inner solid and an outer liquid part. The thickness of the outer part is about 2200 km, and the inner part 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 core land on the 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 star 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 widespread use in science fiction literature. An example is the novel by V.A. Obruchev "Plutonium", 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.

So common with hema of the structure of the earth, including the earth's crust, mantle and core, every year it is more and more improved and refined.

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

So, for example, in order to find out exactly, how many kilometers to the outer part of the core, more years of scientific research will be needed.

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

Layered structure of the Earth

We study what layers the Earth consists of inside

Conclusion

Having considered sectional structure of the earth, we were convinced of how interesting and complex our planet is. The study of its structure in the future will help humanity to understand the riddles. natural phenomena, will allow you to more accurately predict destructive natural disasters, to discover new, not yet developed mineral deposits.

Introduction

1. The main shell of the earth

3. Geothermal regime of the earth

Conclusion

List of sources used

Introduction

Geology is the science of the structure and history of the development of the Earth. The main objects of research are rocks in which the geological record of the Earth is captured, as well as modern physical processes and mechanisms operating both on its surface and in the depths, the study of which makes it possible to understand how the development of our planet took place in the past.

The earth is constantly changing. Some changes occur suddenly and very violently (for example, volcanic eruptions, earthquakes or large floods), but most often - slowly (over a century, a layer of sediments no more than 30 cm thick is removed or accumulated). Such changes are not noticeable throughout the life of one person, but some information has been accumulated about changes over a long period, and even insignificant movements of the earth's crust are recorded with the help of regular accurate measurements.

The history of the Earth began simultaneously with the development of the solar system about 4.6 billion years ago. However, the geological record is characterized by fragmentation and incompleteness, since many ancient rocks have been eroded or overlain by younger sediments. Gaps should be filled through correlations with events that have taken place elsewhere and for which more data is available, as well as by analogy and hypothesis. The relative age of rocks is determined on the basis of the complexes of fossil remains contained in them, and deposits in which such remains are absent, on the basis of the relative position of both. In addition, the absolute age of almost all rocks can be determined by geochemical methods.

In this work, the main shells of the earth, its composition and physical structure.

1. The main shell of the earth

The earth has 6 shells: atmosphere, hydrosphere, biosphere, lithosphere, pyrosphere and centrosphere.

The atmosphere is the outer gaseous envelope of the Earth. Its lower boundary runs along the lithosphere and hydrosphere, and the upper one - at an altitude of 1000 km. In the atmosphere, a distinction is made between the troposphere (the moving layer), the stratosphere (the layer above the troposphere) and the ionosphere (the upper layer).

The average height of the troposphere is 10 km. Its mass is 75% of the total mass of the atmosphere. The air in the troposphere moves both horizontally and vertically.

The stratosphere rises 80 km above the troposphere. Its air, moving only horizontally, forms layers.

The ionosphere extends even higher, which got its name due to the fact that its air is constantly ionized under the influence of ultraviolet and cosmic rays.

The hydrosphere occupies 71% of the Earth's surface. Its average salinity is 35 g / l. The temperature of the ocean surface is from 3 to 32 ° C, the density is about 1. Sunlight penetrates to a depth of 200 m, and ultraviolet rays - to a depth of 800 m.

The biosphere, or the sphere of life, merges with the atmosphere, hydrosphere and lithosphere. Its upper boundary reaches the upper layers of the troposphere, while the lower one runs along the bottom of the ocean troughs. The biosphere is subdivided into the sphere of plants (over 500,000 species) and the sphere of animals (over 1,000,000 species).

The lithosphere - the stone shell of the Earth - is 40 to 100 km thick. It includes continents, islands and oceans. The average height of the continents above sea level: Antarctica - 2200 m, Asia - 960 m, Africa - 750 m, North America - 720 m, South America- 590 m, Europe - 340 m, Australia - 340 m.

The pyrosphere, the fiery shell of the Earth, is located under the lithosphere. Its temperature rises by about 1 ° C for every 33 m depth. Rocks at significant depths, due to high temperatures and high pressure, are probably in a molten state.

The centrosphere, or core of the Earth, is located at a depth of 1800 km. According to most scientists, it is composed of iron and nickel. The pressure here reaches 300,000,000,000 Pa (3,000,000 atmospheres), the temperature is several thousand degrees. The state of the core is still unknown.

The fiery sphere of the Earth continues to cool down. The hard shell thickens, the fiery one thickens. At one time, this led to the formation of solid stone blocks - continents. However, the influence of the fiery sphere on the life of planet Earth is still very great. The outlines of continents and oceans, the climate, and the composition of the atmosphere have repeatedly changed.

Exogenous and endogenous processes continuously change the solid surface of our planet, which, in turn, actively affects the biosphere of the Earth.

2. Composition and physical structure of the earth

Geophysical data and the results of studying deep inclusions indicate that our planet consists of several shells with different physical properties, the change of which reflects as a change chemical composition matter with depth, and the change in its state of aggregation as a function of pressure.

The most top shell The earth - the earth's crust - under the continents has an average thickness of about 40 km (25-70 km), and under the oceans - only 5-10 km (without a layer of water averaging 4.5 km). For the lower edge of the earth's crust, the surface of Mohorovichich is taken - the seismic section, on which the speed of propagation of longitudinal elastic waves increases abruptly with a depth of 6.5-7.5 to 8-9 km / s, which corresponds to an increase in the density of matter from 2.8-3 , 0 to 3.3 g / cm3.

The Earth's mantle extends from the surface of Mohorovichich to a depth of 2,900 km; the upper least dense zone 400 km thick stands out as the upper mantle. The interval from 2900 to 5150 km is occupied by the outer core, and from this level to the center of the Earth, i.e. from 5150 to 6371 km, the inner core is located.

The earth's core has been of interest to scientists since its discovery in 1936. It was extremely difficult to image it due to the relatively small number of seismic waves reaching and returning to the surface. In addition, the extreme temperatures and pressures of the core have long been difficult to reproduce in the laboratory. New research could provide a more detailed picture of the center of our planet. The Earth's core is divided into 2 separate regions: liquid (outer core) and solid (inner), the transition between which lies at a depth of 5,156 km.

Iron is the only element that closely matches the seismic properties of the earth's core and is abundantly abundant in the universe to represent about 35% of its mass in the planet's core. According to modern data, the outer core is a rotating currents of molten iron and nickel that conduct electricity well. It is with him that the origin of the earthly magnetic field, considering that, like a giant generator, electric currents flowing in the liquid core create a global magnetic field. The layer of the mantle in direct contact with the outer core is affected by it, since the temperatures in the core are higher than in the mantle. In some places, this layer generates huge heat and mass flows directed towards the Earth's surface - plumes.

The inner hard core is not connected to the mantle. It is believed that its solid state, despite the high temperature, is provided by the gigantic pressure at the center of the Earth. It is suggested that, in addition to iron-nickel alloys, the core should also contain lighter elements, such as silicon and sulfur, and possibly silicon and oxygen. The question of the state of the Earth's core is still controversial. As the distance from the surface increases, the compression to which the substance is subjected increases. Calculations show that the pressure in the earth's core can reach 3 million atm. At the same time, many substances seem to be metallized - they pass into a metallic state. There was even a hypothesis that the Earth's core consists of metallic hydrogen.

The outer core is also metallic (essentially iron), but unlike the inner core, the metal is here in a liquid state and does not transmit transverse elastic waves. Convective currents in the metallic outer core are responsible for the formation of the Earth's magnetic field.

The Earth's mantle consists of silicates: compounds of silicon and oxygen with Mg, Fe, Ca. The upper mantle is dominated by peridotites - rocks consisting mainly of two minerals: olivine (Fe, Mg) 2SiO4 and pyroxene (Ca, Na) (Fe, Mg, Al) (Si, Al) 2O6. These rocks contain relatively little (< 45 мас. %) кремнезема (SiO2) и обогащены магнием и железом. Поэтому их называют ультраосновными и ультрамафическими. Выше поверхности Мохоровичича в пределах континентальной земной коры преобладают силикатные магматические породы основного и кислого составов. Основные породы содержат 45-53 мас. % SiO2. Кроме оливина и пироксена в состав основных пород входит Ca-Na полевой шпат - плагиоклаз CaAl2Si2O8 - NaAlSi3O8. Кислые магматические породы предельно обогащены кремнеземом, содержание которого возрастает до 65-75 мас. %. Они состоят из кварца SiO2, плагиоклаза и K-Na полевого шпата (K,Na) AlSi3O8. Наиболее распространенной интрузивной породой основного состава является габбро, а вулканической породой - базальт. Среди кислых интрузивных пород чаще всего встречается гранит, a вулканическим аналогом гранита является риолит .

Thus, the upper mantle consists of ultrabasic and ultramafic rocks, and the earth's crust is formed mainly by basic and felsic igneous rocks: gabbros, granites and their volcanic analogs, which, in comparison with peridotites of the upper mantle, contain less magnesium and iron and, at the same time, are enriched in silica. , aluminum and alkali metals.

Under the continents, basic rocks are concentrated in the lower part of the crust, and felsic rocks in the upper part. Beneath the oceans, the earth's thin crust consists almost entirely of gabbros and basalts. It is firmly established that the main breeds that are different estimates make up from 75 to 25% of the mass of the continental crust and almost all of the oceanic crust, were melted from the upper mantle in the process of magmatic activity. Acidic rocks are usually considered as the product of partial re-melting of basic rocks within the continental crust. Peridotites from the uppermost part of the mantle are depleted in low-melting components, which are transferred to the earth's crust during magmatic processes. Especially "depleted" is the upper mantle under the continents, where the thickest crust arose.

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

The earth consists of a core, mantle, crust, lithosphere, hydrosphere, etc. Due to the influence 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. Top part 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 hitting the Earth's surface (lithosphere, hydrosphere), which are destructive to all living things. The lower layers of the troposphere - up to 5 km from sea level - are the air habitat, while the lowest layers are most densely populated - up to 100 m from the land surface or. The greatest impact from human activities, 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 the height of 100 km above sea level. The stratosphere is filled with a rarefied gas (nitrogen, hydrogen, helium, etc.). It passes into the ionosphere.

3. Ionosphere - the upper layer, passing into the 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 the regions beyond the Arctic Circle.

From an ecological point of view, the troposphere is of the greatest importance.

Brief characteristics 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.

The lithosphere is the outer hard shell of the earth, 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 hard 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 is (for the most part) covered with thin layer fertile surface - soil. Soil is one of the environments of life, and the lithosphere is a substrate on which various organisms live.

Hydrosphere - aquatic shell the earth's surface, formed by the totality of all bodies of water on Earth. The thickness of the hydrosphere is different for different sites, but the average depth of the ocean is 3.8 km, and in some depressions - up to 11 km. The hydrosphere is the source of water for all organisms living on Earth, it is a powerful geological force that carries out the cycle of 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 emergence 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 Earth's shells 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 envelope inhabited by living organisms.

The boundaries of the biosphere are determined by the presence of conditions necessary for the normal life of organisms. The upper part of the biosphere is limited by the intensity of ultraviolet radiation, and the lower one is 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 to be 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 boundary of the contact of the lithosphere and hydrosphere with the atmosphere. The density of life in the soil is very high.

The mass of living matter is small compared to the mass of the earth's crust and hydrosphere, but plays a huge role in the processes of changing the earth's crust.

The biosphere is the totality of all biogeocenoses on Earth, therefore it is considered the highest ecosystem on 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 planet's biological resources, if there is no sharp interference in natural ecological processes by various forces of a geological or interplanetary nature. At present, as indicated above, anthropogenic factors affecting the biosphere have assumed 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 enhanced 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", two approaches are distinguished:

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

2. "The noosphere is a biosphere, the development of which is guided by the human mind." This concept widely represented in and is a concept in the broad sense of the essence of the noosphere, since the influence of the human mind on the biosphere can be both positive and negative, and the latter very often prevails. The technosphere is part of the noosphere - a part of the noosphere associated with human production activities.

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

Brief description of emergencies arising on the Earth's surface and their classification

Emergencies constantly occurring on the Earth's surface play an important role in natural ecological processes. They destroy local biogeocenoses, and if they are repeated cyclically, then in some cases they are environmental factors that contribute to the course of evolutionary processes.

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

The concept of "emergencies" in to a greater extent applicable to human activities, but it also applies to natural communities.

By origin, emergencies are divided into natural and anthropogenic (man-made).

Natural emergencies occur 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, taking the form of shock waves and elastic vibrations (seismic waves).

Earthquakes occur mainly due to underground volcanic phenomena, displacement of strata relative to each other, but they can also have a man-made character and arise due to the collapse of mining operations. During earthquakes, displacements, vibrations and vibration of rocks from seismic waves and tectonic movements of the earth's crust occur, which leads to surface destruction - the appearance of cracks, faults, etc., as well as to the occurrence of fires, destruction of buildings.

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

In case of landslides, the surface is disturbed, biocenoses perish, 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 mass of rocks), 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 economic activity man, heavily polluting the region adjacent to the volcanoes. Volcanic eruptions are accompanied by other catastrophic natural phenomena - fires, landslides, floods, etc.

Mudflows are short-term flash floods that carry a large number of sand, pebbles, coarse gravel and stones that have the character of mud-stone streams.

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

Snow avalanches are called avalanches of snow, carrying with them 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 the 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.

Flooding is the flooding of an area with water within river valleys, lake coasts, seas and oceans.

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

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

Tsunamis have natural and man-made causes. TO natural reasons include earthquakes, seaquakes and underwater volcanic eruptions, and man-made - underwater nuclear explosions.

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

Events causing emergency situations also occur. These include hurricanes, tornadoes, different kinds storms.

Hurricanes are tropical and extratropical cyclones, which have a very low pressure in the center, are accompanied by the emergence of winds with high speed and destructive force.

Distinguish between weak, strong and extreme hurricanes, which cause the appearance of showers, sea waves and the destruction of terrestrial objects, the death of various organisms.

Eddy storms (squalls) - atmospheric phenomena associated with the occurrence strong winds, possessing great destructive power and a significant territory of distribution. Distinguish between snow storms, dust storms and dustless storms. The squalls cause the transfer of the upper layers of the soil, their destruction, the death of plants, animals, the destruction of structures.

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

The force 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 emergencies, there are other phenomena that cause them, the cause of which is human activity. Anthropogenic emergencies include:

1. Transport accidents. Violation of traffic rules on various highways (road, rail, river, sea) leads to the death of vehicles, people, animals, etc. various substances, including those that lead to the death of organisms of all kingdoms (for example, pesticides, etc.). As a result of traffic accidents, fires may occur and gases (hydrogen chloride, ammonia, fire and explosive substances) may enter.

2. Accidents at large enterprises. Violation technological processes, non-observance of the rules for the operation of equipment, imperfection of technology can cause a release into environment harmful compounds causing various diseases humans and animals, contributing to the appearance of mutations in the organisms of plants and animals, as well as lead to the destruction of buildings and the outbreak of fires. The most dangerous are accidents at enterprises using. Accidents at nuclear power plants (NPP) cause great harm, since in addition to the usual damaging factors (mechanical destruction, release harmful substances single action, fires) accidents at nuclear power plants are characterized by damage to the area by radionuclides, penetrating radiation and the radius of damage in this case significantly exceeds the likelihood of 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 have a natural character, for example, due to lightning discharges (lightning). Violations in power lines can also be the cause of such fires. Fires destroy natural communities of organisms in large areas, causing great economic damage to human economic activity.

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