Geographical envelope, its properties and integrity

21.1. The concept of a geographical shell

The geographic envelope is an integral continuous near-surface part of the Earth, within which the lithosphere, hydrosphere, atmosphere and living matter. This is the most complex and diverse material system of our planet. The geographic shell includes the entire hydrosphere, the lower layer of the atmosphere, the upper part of the lithosphere and the biosphere, which are its structural parts.

The geographical shell does not have clear boundaries, so scientists conduct them in different ways. Usually, the ozone screen, located at an altitude of about 25–30 km, is taken as the upper limit, where most of the ultraviolet solar radiation, which has a detrimental effect on living organisms, is retained. At the same time, the main processes that determine the weather and climate, and hence the formation of landscapes, occur in the troposphere, the height of which varies in latitudes from 16–18 km near the equator to 8 km above the poles. The base of the weathering crust is most often considered the lower boundary on land. This part earth's surface is subject to the strongest changes under the influence of the atmosphere, hydrosphere and living organisms. Its maximum power is about one kilometer. Thus, the total thickness of the geographic envelope on land is about 30 km. In the ocean, the bottom of the geographic shell is considered to be its bottom.

However, it should be noted that there are the greatest differences among scientists regarding the position of the lower boundary of the geographic envelope. We can give five or six points of view on this issue with appropriate justifications. At the same time, the boundary is drawn at depths from several hundred meters to tens and even hundreds of kilometers, and in different ways within the continents and oceans, as well as various parts of the continents.

There is no unity in regard to the name of the geographic shell. The following terms have been proposed for its designation: landscape shell or sphere, geographic sphere or environment, biogenosphere, epigeosphere, and a number of others. However, at present, most geographers adhere to the names and boundaries of the geographic shell that we have given.

The idea of ​​a geographical shell as a special natural formation was formulated in science in the 20th century. The main merit in the development of this idea belongs to Academician A. A. Grigoriev. He also revealed the main features of the geographical shell, which are as follows:

Compared to the bowels of the Earth and the rest of the atmosphere, the geographic envelope is characterized by a greater variety of material composition, as well as the energy entering non-human forms and the forms of their transformation.

The substance in the geographic envelope is in three states of aggregation (outside it, one state of matter prevails).

All processes here proceed due to both solar and intraterrestrial energy sources (outside the geographic envelope - mainly due to one of them), and solar energy absolutely prevails.

A substance in a geographic envelope has a wide range of physical characteristics (density, thermal conductivity, heat capacity, etc.). Only here is life. The geographical envelope is the arena of human life and activity.

5. The general process that connects the spheres that make up the geographical envelope is the movement of matter and energy, which takes place in the form of cycles of matter and in changes in the components of energy balances. All cycles of matter occur at different speeds and at different levels of substance organization (macro level, micro levels of phase transitions and chemical transformations). Part of the energy entering the geographic shell is conserved in it, the other part in the process of the circulation of substances leaves the planet, having previously experienced a number of transformations.

The geographical envelope consists of components. These are certain material formations: rocks, water, air, plants, animals, soil. Components differ in physical state (solid, liquid, gaseous), level of organization (non-living, living, bio-inert - a combination of living and non-living, which includes the soil), chemical composition, as well as the degree of activity. According to the last criterion, the components are divided into stable (inert) - rocks and soils, mobile - water and air, and active - living matter.

Sometimes partial shells are considered as components of the geographic shell - the lithosphere, atmosphere, hydrosphere and biosphere. This is not a completely correct idea, because not all of the lithosphere and atmosphere are part of the geographic shell, and the biosphere does not form a spatially isolated shell: it is the area of ​​distribution of living matter within a part of other shells.

Geographical shell geographically and in volume almost coincides with the biosphere. However, there is no single point of view regarding the relationship between the biosphere and the geographic envelope. Some scientists believe that the concepts of "biosphere" and "geographical envelope" are very close or even identical. In this regard, proposals were made to replace the term "geographical envelope" with the term "biosphere" as more common and familiar to the general public. Other geographers consider the biosphere as a certain stage in the development of the geographical envelope (three main stages are distinguished in its history: geological, biogenic and modern anthropogenic). According to others, the terms "biosphere" and "geographical shell" are not identical, since the concept of "biosphere" focuses on the active role of living matter in the development of this shell, and this term has a special biocentric orientation. Apparently, one should agree with the latter approach.

The geographical shell is now considered as a system, and the system is complex (consisting of many material bodies), dynamic (continuously changing), self-regulating (having a certain

stable stability) and open (continuously exchanging with environment matter, energy and information).

The geographic envelope is heterogeneous. It has a tiered vertical structure, consisting of individual spheres. The substance is distributed in it by density: the higher the density of the substance, the lower it is located. At the same time, the geographic shell has the most complex structure at the contact of the spheres: the atmosphere and the lithosphere (the land surface), the atmosphere and the hydrosphere (the surface layers of the World Ocean), the hydrosphere and the lithosphere (the bottom of the World Ocean), as well as in the coastal strip of the ocean, where the hydrosphere is in contact, lithosphere and atmosphere. With distance from these contact zones, the structure of the geographic envelope becomes simpler.

The vertical differentiation of the geographic shell served as the basis for the well-known geographer F.N. Milkov to single out a landscape sphere inside this shell - a thin layer of direct contact and active interaction of the earth's crust, atmosphere and water shell. The landscape sphere is the biological focus of the geographic envelope. Its thickness varies from several tens of meters to 200-300 m. ). The most common of them is water-surface. It includes a 200-meter surface layer of water and a layer of air 50 m high. The composition of the terrestrial version of the landscape sphere, better studied than others, includes a surface layer of air 30–50 m high, vegetation with the animal world inhabiting it, soil and modern weathering crust . Thus, the landscape sphere is the active core of the geographic envelope.

The geographic envelope is heterogeneous not only in the vertical but also in the horizontal direction. In this regard, it is divided into separate natural complexes. The differentiation of the geographic envelope into natural complexes is due to the uneven distribution of heat in its various parts and the heterogeneity of the earth's surface (the presence of continents and oceanic depressions, mountains, plains, elevations, etc.). The largest natural complex is the geographical envelope itself. Geographical complexes also include continents and oceans, natural areas(tundra, forests, steppes, etc.), as well as regional natural formations, such as the East European Plain, the Sahara Desert, the Amazonian Lowland, etc. Small natural complexes are confined to individual hills, their slopes, river valleys and their individual areas (channel, floodplain, floodplain terraces) and other meso- and microforms of relief. The smaller the natural complex, the more homogeneous the natural conditions within it. Thus, the entire geographic envelope has a complex mosaic structure; it consists of natural complexes of different ranks.

The geographical shell has gone through a long and complex history of development, which can be divided into several stages. It is assumed that the primary cold earth formed, like other planets, from interstellar dust and gases about 5 billion years ago. In the pregeological period of the Earth's development, which ended 4.5 billion years ago, its accretion took place, the surface was bombarded by meteorites and experienced powerful tidal fluctuations from the nearby Moon. The geographic envelope as a complex of spheres did not exist then.

The first one is the geological stage of the development of the geographic envelope, which began together with the early geological stage of the Earth's development (4.6 billion years ago) and captured its entire pre-Cambrian history, continuing until the beginning of the Phanerozoic (570 million years ago). This was the period of the formation of the hydrosphere and atmosphere during degassing of the mantle. The concentration of heavy elements (iron, nickel) in the center of the Earth and its rapid rotation caused the emergence of a powerful magnetic field around the Earth, protecting the earth's surface from cosmic radiation. Thick strata of the continental crust arose along with the primary oceanic, and by the end of the stage, the continental crust began to split into plates and, together with the resulting young oceanic crust, began to drift through the viscous asthenosphere.

At this stage, 3.6–3.8 billion years ago, the first signs of life appeared in the aquatic environment, which, by the end of the geological stage, conquered the oceanic spaces of the Earth. At that time, organic matter did not yet play an important role in the development of the geographic envelope, as it does now.

The second stage in the development of the geographic envelope (from 570 million to 40 thousand years ago) includes the Paleozoic, Mesozoic, and almost the entire Cenozoic. This stage is characterized by the formation of an ozone screen, the formation of the modern atmosphere and hydrosphere, a sharp qualitative and quantitative leap in the development of the organic world, and the beginning of soil formation. Moreover, as in the previous stage, periods of evolutionary development alternated with periods that had a catastrophic character. This applies to both inorganic and organic nature. Thus, periods of calm evolution of living organisms (homeostasis) were replaced by periods of mass extinction of plants and animals (four such periods were recorded during the stage under consideration).

The third stage (40 thousand years ago - our time) begins with the appearance of modern Homo sapiens, more precisely, with the beginning of a noticeable and ever-increasing impact of man on his natural environment 1 .

In conclusion, it should be said that the development of the geographical shell proceeded along the line of complication of its structure, accompanied by processes and phenomena that were still far from known by man. As one of the geographers successfully noted in this regard, the geographic shell is a single unique object with a mysterious past and an unpredictable future.

21.2. The main regularities of the geographical shell

The geographic envelope has a number of general patterns. These include: integrity, rhythm of development, horizontal zonality, azonality, polar asymmetry.

Integrity is the unity of the geographical shell, due to the close relationship of its constituent components. Moreover, the geographic envelope is not a mechanical sum of components, but a qualitatively new formation that has its own characteristics and develops as a whole. As a result of the interaction of components in natural complexes, the production of living matter is carried out and soil is formed. A change within the natural complex of one of the components leads to a change in the others and the natural complex as a whole.

Many examples can be cited to support this. The most striking of them for the geographic envelope is the example of the appearance of the El Niño current in the equatorial Pacific Ocean.

Usually trade winds blow here and sea currents move from the coast of America to Asia. However, with an interval of 4-7 years, the situation changes. The winds, for unknown reasons, change their direction to the opposite, heading towards the shores of South America. Under their influence, a warm El Niño current arises, pushing the cold waters of the Peruvian Current, rich in plankton, from the coast of the mainland. This current appears off the coast of Ecuador in the band 5 - 7 ° S. sh., washes the coast of Peru and the northern part of Chile, penetrating up to 15 ° S. sh., and sometimes to the south. This usually happens at the end of the year (the name of the current, which usually occurs around Christmas, means “baby” in Spanish and comes from the baby Christ), lasts 12-15 months and is accompanied by catastrophic consequences for South America: heavy rainfall in the form of downpours, floods, the development of mudflows, landslides, erosion, the reproduction of harmful insects, the departure of fish from the coast due to the arrival of warm waters, etc. To date, the dependence of weather conditions in many regions of our planet on the El Niño current has been revealed: unusual heavy rains in Japan, severe droughts in South Africa, droughts and wildfires in Australia, violent floods in England, heavy winter precipitation in the Eastern Mediterranean. Its occurrence also affects the economy of many countries, primarily the production of agricultural crops (coffee, cocoa beans, tea, sugar cane, etc.) and fishing. The most intense in the last century was El Niño in 1982–1983. It is estimated that during this time the current caused the world economy material damage in the amount of about $ 14 billion and led to the death of 20 thousand people.

Other examples of the manifestation of the integrity of the geographic envelope are shown in Scheme 3.

The integrity of the geographic shell is achieved by the circulation of energy and matter. Energy cycles are expressed by balances. For the geographic envelope, radiation and heat balances are most typical. As for the cycles of matter, the matter of all spheres of the geographic envelope is involved in them.

Cycles in the geographic envelope are different in their complexity. Some of them, for example, the circulation of the atmosphere, the system of sea currents, or the movement of masses in the bowels of the Earth, are mechanical movements, others (the water cycle) are accompanied by a change in the aggregate state of matter, and others (biological circulation and changes in matter in the lithosphere) are chemical transformations.

As a result of the cycles in the geographic shell, there is an interaction between the private shells, during which they exchange matter and energy. It is sometimes argued that the atmosphere, hydrosphere and lithosphere penetrate each other. In fact, this is not so: it is not the geospheres that penetrate each other, but their components. Thus, solid particles of the lithosphere enter the atmosphere and hydrosphere, air penetrates the lithosphere and hydrosphere, etc. Particles of matter that have fallen from one sphere to another become an integral part of the latter. Water and solid particles of the atmosphere are its constituent parts, just like gases and solid particles in water bodies belong to the hydrosphere. The presence of substances that have fallen from one shell into another form, to one degree or another, the properties of this shell.

A typical example of a cycle that connects all the structural parts of a geographic envelope is the water cycle. The general, global and private cycles are known: ocean - atmosphere, continent - atmosphere, intra-oceanic, intra-atmospheric, intra-terrestrial, etc. All water cycles occur due to the mechanical movement of huge masses of water, but many of them - between different spheres, are accompanied by phase transitions water or occur with the participation of some specific forces, such as surface tension. The global water cycle, covering all spheres, is accompanied, in addition, by the chemical transformations of water - the entry of its molecules into minerals, into organisms. The complete (global) water cycle with all its particular components is well represented in the scheme of L. S. Abramov (Fig. 146). In total, there are 23 cycles of moisture circulation.

Integrity is the most important geographical regularity, on the knowledge of which the theory and practice of rational nature management is based. Accounting for this regularity makes it possible to foresee possible changes in nature, to give a geographical forecast of the results of human impact on nature, to carry out a geographical examination of projects related to the economic development of certain territories.

rice. 146. Complete and partial water cycles in nature

The geographical shell is characterized by the rhythm of development - the repetition in time of certain phenomena. There are two forms of rhythm: periodic and cyclic. Under the periods understand the rhythms of the same duration, under the cycles - a variable duration. There are rhythms in nature different duration- diurnal, intra-secular, centuries-old and super-secular, having different origins. Manifesting at the same time, rhythms are superimposed one on another, in some cases strengthening, in others - weakening each other.

The daily rhythm, due to the rotation of the Earth around its axis, manifests itself in changes in temperature, pressure, air humidity, cloudiness, wind strength, in the phenomena of ebbs and flows, the circulation of breezes, in the functioning of living organisms and in a number of other phenomena. The daily rhythm at different latitudes has its own specifics. This is due to the duration of illumination and the height of the Sun above the horizon.

The annual rhythm is manifested in the change of seasons, in the formation of monsoons, in the change in the intensity of exogenous processes, as well as in the processes of soil formation and destruction of rocks, seasonality in human economic activity. In different natural regions, a different number of seasons is distinguished. So, in the equatorial zone there is only one season of the year - hot and humid, in the savannahs there are two seasons: dry and wet. In temperate latitudes, climatologists even suggest distinguishing six seasons of the year: in addition to the well-known four, two more - pre-winter and pre-spring. Pre-winter is the period from the moment the average daily temperature passes through 0 ° C in autumn until the establishment of a stable snow cover. Prespring begins with the beginning of the melting of the snow cover until its complete disappearance. As can be seen, the annual rhythm is best expressed in the temperate zone and very weakly in the equatorial zone. The seasons of the year in different regions may have different names. It is hardly legitimate to single out the winter season at low latitudes. It should be borne in mind that the reasons for the annual rhythm are different in different natural regions. So, in subpolar latitudes, it is determined by the light regime, in temperate latitudes - by the course of temperatures, in subequatorial latitudes - by the moisture regime.

Of the intrasecular rhythms, the 11-year rhythms associated with changes in solar activity are most clearly expressed. It has a great influence on the Earth's magnetic field and ionosphere and, through them, on many processes in the geographic envelope. This leads to periodic changes in atmospheric processes, in particular, to deepening of cyclones and strengthening of anticyclones, fluctuations in river flow, and changes in the intensity of sedimentation in lakes. The rhythms of solar activity affect the growth of woody plants, which is reflected in the thickness of their growth rings, contribute to periodic outbreaks of epidemic diseases, as well as the mass reproduction of pests of forests and crops, including locusts. As the famous heliobiologist A.L. Chizhevsky, 11-year rhythms affect not only the development of many natural processes, but also the organism of animals and humans, as well as their life and activities. It is interesting to note that some geologists now associate tectonic activity with solar activity. A sensational statement on this subject was made at the International Geological Congress held in 1996 in Beijing. Employees of the Institute of Geology of China revealed the cyclicity of earthquakes in the eastern part of their country. Exactly every 22 years (doubled solar cycle) in this area there is a perturbation of the earth's crust. It is preceded by sunspot activity. Scientists have studied historical chronicles since 1888 and found complete confirmation of their conclusions regarding the 22-year cycles of earth's crust activity leading to earthquakes.

Centuries-old rhythms are manifested only in individual processes and phenomena. Among them, the rhythm lasting 1800–1900 years, established by A.V. Shnitnikov. Three phases are distinguished in it: transgressive (of a cool-humid climate), developing rapidly, but short (300–500 years); regressive (dry and warm climate), developing slowly (600 - 800 years); transitional (700–800 years). In the transgressive phase, glaciation on Earth intensifies, river flow increases, and the level of lakes rises. In the regressive phase, glaciers, on the contrary, retreat, rivers become shallow, and the water level in lakes decreases.

The rhythm under consideration is associated with a change in tide-forming forces. Approximately every 1800 years, the Sun, Moon and Earth are in the same plane and on the same straight line, and the distance between the Earth and the Sun becomes the smallest. Tidal forces reach their maximum value. In the World Ocean, the movement of water in the vertical direction increases to a maximum - deep cold waters come to the surface, which leads to cooling of the atmosphere and the formation of a transgressive phase. Over time, the “parade of the Moon, Earth and Sun” is disturbed and humidity returns to normal.

The supersecular cycles include three cycles associated with changes in the orbital characteristics of the Earth: precession (26 thousand years), a complete oscillation of the ecliptic plane relative to the earth's axis (42 thousand years), a complete change in the eccentricity of the orbit (92 - 94 thousand years).

The longest cycles in the development of our planet are tectonic cycles lasting about 200 million years, known to us as the Baikal, Caledonian, Hercynian and Mesozoic-Alpine epochs of folding. They are caused by cosmic causes, mainly by the onset of galactic summer in a galactic year. The galactic year is understood as the revolution of the solar system around the center of the galaxy, lasting the same number of years. When the system approaches the center of the Galaxy, in perigalactia, i.e., "galactic summer", gravity increases by 27% compared to apogalactia, which leads to an increase in tectonic activity on Earth.

There are also reversals of the Earth's magnetic field with a duration of 145–160 Ma.

Rhythmic phenomena do not completely repeat at the end of the rhythm the state of nature that was at its beginning. This is precisely what explains the directed development of natural processes, which, when rhythm is superimposed on progress, ultimately turns out to be going in a spiral.

The study of rhythmic phenomena has great importance to develop geographic forecasts.

The planetary geographical regularity, established by the great Russian scientist V.V. Dokuchaev, is zoning - a regular change in natural components and natural complexes in the direction from the equator to the poles. Zoning is due to the unequal amount of heat coming to different latitudes due to the spherical shape of the Earth. The distance of the Earth from the Sun is also important. The dimensions of the Earth are also important: its mass allows it to keep an air shell around it, without which there would be no zoning. Finally, zoning is complicated by a certain inclination of the earth's axis to the plane of the ecliptic.

On Earth, the climate, land and ocean waters, weathering processes, some landforms formed under the influence of external forces (surface waters, winds, glaciers), vegetation, soils, and wildlife are zonal. The zonality of components and structural parts predetermines the zonality of the entire geographic envelope, i.e., geographic or landscape zonality. Geographers distinguish between component (climate, vegetation, soil, etc.) and complex (geographical or landscape) zonality. The concept of component zoning has developed since ancient times. Complex zoning was discovered by V.V. Dokuchaev.

The largest zonal subdivisions of the geographic shell are geographic belts. They differ from each other in temperature conditions, general features of the circulation of the atmosphere. On land, the following geographical zones are distinguished: equatorial and in each hemisphere - subequatorial, tropical, subtropical, temperate, as well as in the northern hemisphere - subarctic and arctic, and in the southern - subantarctic and antarctic. In total, thus, 13 natural belts are distinguished on land. Each of them has its own characteristics for human life and economic activity. These conditions are most favorable in three zones: subtropical, temperate and subequatorial (by the way, all three have a well-defined seasonal rhythm of nature development). They are more intensively mastered by man than others.

Belts similar in name (with the exception of subequatorial ones) have also been identified in the World Ocean. The zonality of the World Ocean is expressed in sublatitudinal changes in temperature, salinity, density, gas composition of water, in the dynamics of the upper water column, as well as in the organic world. D.V. Bogdanov distinguishes natural oceanic belts - "vast water spaces covering the surface of the ocean and the adjacent upper layers to a depth of several hundred meters, in which the features of the nature of the oceans (temperature and salinity of water, currents, ice conditions, biological and some hydrochemical indicators) are clearly visible, directly or indirectly due to the influence of the latitude of the place ”(Fig. 147). The boundaries of the belts were drawn by him along oceanological fronts - the boundaries of the distribution and interaction of waters with different properties. Oceanic belts are very well combined with physical and geographical zones on land; the exception is the subequatorial belt of land, which does not have its own oceanic counterpart.

Within the belts on land, according to the ratio of heat and moisture, natural zones are distinguished, the names of which are determined by the type of vegetation prevailing in them. So, for example, in the subarctic zone there are zones of tundra and forest-tundra, in the temperate zone there are zones of forests, forest-steppes, steppes, semi-deserts and deserts, in the tropical zone there are zones of evergreen forests, semi-deserts and deserts.

Rice. 147. Geographical zonation of the World Ocean (in conjunction with the geographical zones of land) (according to D.V. Bogdanov)

Geographical zones are subdivided into subzones according to the degree of manifestation of zonal features. Theoretically, in each zone, three subzones can be distinguished: the central one, with the most typical features for the zone, and

marginal, bearing some features characteristic of adjacent zones. An example is the forest zone of the temperate zone, in which subzones of the northern, middle and southern taiga, as well as subtaiga (coniferous-deciduous) and broad-leaved forests, are distinguished.

Due to the heterogeneity of the earth's surface, and consequently, the conditions of moisture in various parts continents zones and subzones do not always have a latitudinal strike. Sometimes they stretch almost in a meridional direction, as, for example, in the southern half of North America or in eastern Asia. Therefore, it is more correct to call zonality not latitudinal, but horizontal. In addition, many zones are not distributed around the globe like belts; some of them are found only in the west of the continents, in the east or in their center. This is explained by the fact that the zones were formed as a result of hydrothermal, and not radiation, differentiation of the geographic envelope, i.e., due to the different ratio of heat and moisture. In this case, only the distribution of heat is zonal; the distribution of moisture depends on the distance of the territory from sources of moisture, i.e., from the oceans.

In 1956 A.A. Grigoriev and M.I. Budyko formulated the so-called periodic law of geographical zoning, where each natural zone is characterized by its quantitative ratios of heat and moisture. Heat is estimated in this law by the radiation balance, and the degree of moisture is estimated by the radiation dryness index K B (or RIS) = B / (Z x r), where B is the annual radiation balance, r is the annual amount of precipitation, L is the latent heat of vaporization.

The radiation dryness index shows what proportion of the radiation balance is spent on the evaporation of precipitation: if the evaporation of precipitation requires more heat than it comes from the Sun, and part of the precipitation remains on Earth, then the humidification of such a territory is sufficient or excessive. If more heat comes in than is spent on evaporation, then the excess heat heats the earth's surface, which at the same time experiences a lack of moisture: K B< 0,45 – климат избыточно влажный, К Б = 0,45-Н,0 – влажный, К Б = 1,0-^3,0 – недостаточно влажный, К Б >3.0 - dry.

It turned out that, although zoning is based on the increase in the radiation balance from high latitudes to low latitudes, the landscape appearance of the natural zone is most of all determined by moistening conditions. This indicator determines the type of zone (forest, steppe, desert, etc.), and the radiation balance determines its specific appearance (temperate latitudes, subtropical, tropical, etc.). Therefore, in each geographical zone, depending on the degree of moisture, their own humid and arid natural zones have formed, which can be replaced at the same latitude, depending on the degree of moisture. It is characteristic that in all belts the optimal conditions for the development of vegetation are created when the radiation index of dryness is close to one.

Rice. 148. Periodic law of geographical zonality. K B is the radiation index of dryness. (The diameters of the circles are proportional to the biological productivity of landscapes)

The periodic law of geographic zoning is written in the form of a matrix table, in which the radiation dryness index is calculated horizontally, and the annual radiation balance values ​​\u200b\u200bare vertically (Fig. 148).

Speaking of zoning as a general pattern, it should be borne in mind that it is not equally expressed everywhere. It manifests itself most clearly in the polar, equatorial and equatorial latitudes, as well as in the inland: flat conditions of temperate and subtropical latitudes. The latter include primarily the East European and West Siberian plains, which are elongated in the meridional direction. Apparently, this helped V.V. Dokuchaev to identify the pattern under consideration, since he studied it on the East European Plain. The fact that V. V. Dokuchaev was a soil scientist played a role in determining the complex zonality, and the soil, as is known, is an integral indicator of the natural conditions of the territory.

Some scientists (O. K. Leontiev, A. P. Lisitsyn) trace natural zones in the thickness and at the bottom of the oceans. However, the natural complexes identified by them here cannot be called physico-geographical zones in the conventional sense, i.e., their isolation is not affected by the zonal distribution of radiation, which is the main cause of zoning on the Earth's surface. Here we can talk about the zonal properties of water masses and bottom sediments of flora and fauna acquired indirectly through water exchange with the near-surface water mass, redeposition of zonal terrigenous and biogenic sediments, and trophic dependence of bottom fauna on dead organic residues coming from above.

The zoning of the geographic envelope as a planetary phenomenon is violated by the opposite property - azonality.

The azonality of a geographic envelope is understood as the distribution of some object or phenomenon out of connection with the zonal features of a given territory. The reason for the azonality is the heterogeneity of the earth's surface: the presence of continents and oceans, mountains and plains on the continents, the peculiarity of moistening conditions and other properties of the geographical envelope. There are two main forms of manifestation of azonality - sectoral geographic zones and altitudinal zonality.

Sectorization, or longitudinal differentiation, of geographic zones is determined by moisture (in contrast to latitudinal zones, where not only moisture, but also heat supply play an important role). Sectorism is manifested primarily in the formation of three sectors within the belts - the continental and two oceanic. However, they are not expressed equally everywhere, which depends on the geographic location of the continent, its size and configuration, as well as on the nature of atmospheric circulation.

Geographic sectoring is most fully expressed on the largest continent of the Earth - in Eurasia, from the Arctic to the equatorial belt inclusive. Longitudinal differentiation is most pronounced here in the temperate and subtropical zones, where all three sectors are clearly expressed. There are two sectors in the tropical zone. Longitudinal differentiation is weakly expressed in the equatorial and subpolar belts.

Another reason for the azonality of the geographic envelope, which violates zoning and sectoring, is the location of mountain systems, which can prevent the penetration of air masses carrying moisture and heat into the depths of the continents. This is especially true for those ridges of the temperate zone, which are located submeridionally on the path of cyclones following from the west.

The azonal nature of landscapes is often determined by the features of the rocks that compose them. Thus, the occurrence of soluble rocks close to the surface leads to the formation of peculiar karst landscapes, which differ significantly from the surrounding zonal natural complexes. In the areas of distribution of water-glacial sands, landscapes of the Polissya type are formed. Figure 149 shows the location of geographic zones and sectors within them on a hypothetical flat continent, built on the basis of the actual distribution of land on the globe at different latitudes. The same figure clearly illustrates the asymmetry of the geographic envelope.

In conclusion, we note that azonality, as well as zoning, is a general pattern. Each area of ​​the earth's surface, due to its heterogeneity, reacts in its own way to the incoming solar energy and, therefore, acquires specific features that are formed against the general zonal background. In essence, azonation is a specific form of manifestation of zonation. Therefore, any part of the earth's surface is simultaneously zonal and azonal.

Altitudinal zonality is a natural change of natural components and natural complexes with an ascent to the mountains from their foot to the peaks. It is due to climate change with height: temperature decrease and precipitation increase up to a certain height (up to 2-3 km) on the windward slopes.

Altitudinal zonality has much in common with horizontal zonality: when ascending mountains, the change of belts occurs in the same sequence as on the plains, when moving from the equator to the poles. However, the natural belts in the mountains are changing much faster than the natural zones in the plains. In the northern hemisphere, in the direction from the equator to the poles, the temperature decreases by about 0.5 ° C for every degree of latitude (111 km), while in the mountains it drops by an average of 0.6 ° C for every 100 m.

Rice. 149. Scheme of geographical zones and main zonal types of landscapes on a hypothetical continent (the dimensions of the depicted continent correspond to half the land area of ​​the globe on a scale of 1: 90,000,000), the configuration - its location in latitudes, the surface - a low plain (according to A. M. Ryabchikov and etc.)

There are other differences: in the mountains in all belts, with a sufficient amount of heat and moisture, there is a special belt of subalpine and alpine meadows, which is not found on the plains. Moreover, each belt of mountains, similar in name to the plain, differs significantly from it, because they receive solar radiation of different composition and have different lighting conditions.

The altitudinal zonality in the mountains is formed not only under the influence of changes in altitude, but also in the features of the relief of the mountains. In this case, the exposure of slopes, both insolation and circulation, plays an important role. Under certain conditions, an inversion of altitudinal zonality is observed in the mountains: when cold air stagnates in intermountain basins, the belt of coniferous forests, for example, can occupy a lower position compared to the belt of broad-leaved forests. On the whole, the altitudinal zonality is much more diverse than the horizontal zonality and, moreover, manifests itself at close distances.

However, there is a close relationship between horizontal zonality and altitudinal zonality. Altitudinal zonality begins in the mountains with an analog of the horizontal zone within which the mountains are located. So, in the mountains located in the steppe zone, the lower belt is mountain-steppe, in the forest - mountain-forest, etc. Horizontal zonality determines the type of altitudinal zonality. In each horizontal zone, mountains have their own range (set) of altitudinal belts. The number of altitudinal belts depends on the height of the mountains and their location. The higher the mountains and the closer to the equator they are located, the richer their spectrum of belts.

The nature of the altitudinal zonality is also affected by the sector nature of the geographic envelope: the composition of the vertical belts differs depending on which particular sector a particular mountain range is located in. The generalized structure of the altitudinal zonality of landscapes in different geographical zones (at different latitudes) and in various sectors is shown in Figure 150. Similarly to the altitudinal zonality in mountains on land, one can speak of deep zonality in the ocean.

One of the main (and according to Academician K.K. Markov, the main) regularities of the geographic envelope should be considered polar asymmetry. The reason for this pattern is primarily the asymmetry of the figure of the Earth. As you know, the northern semi-axis of the Earth is 30 m longer than the southern one, so that the Earth is more flattened at the South Pole. The location of continental and oceanic masses on the Earth is asymmetrical. In the northern hemisphere, land occupies 39% of the area, and in the southern hemisphere - only 19%. Around the North Pole is the ocean, around the South - the mainland of Antarctica. On the southern continents, platforms occupy from 70 to 95% of their area, on the northern continents - 30 - 50%. In the northern hemisphere there is a belt of young folded structures (Alpine-Himalayan), stretching in a latitudinal direction. It has no analogue in the southern hemisphere. In the northern hemisphere, between 50 and 70 °, the most geostructurally elevated land areas are located (Canadian, Baltic, Anabar. Aldan shields). In the southern hemisphere at these latitudes there is a chain of oceanic depressions. In the northern hemisphere there is a continental ring framing the polar ocean, in the southern hemisphere there is an oceanic ring that borders the polar continent.

The asymmetry of land and sea entails the asymmetry of other components of the geographic envelope. Thus, in the oceanosphere, the systems of sea currents in the northern and southern hemispheres do not repeat each other; moreover, warm currents in the northern hemisphere extend up to arctic latitudes, while in the southern hemisphere only up to a latitude of 35°. The water temperature in the northern hemisphere is 3° higher than in the southern.

The climate of the northern hemisphere is more continental than that of the southern one (the annual air temperature amplitude is 14 and 6 °C, respectively). In the northern hemisphere, there is weak continental glaciation, strong sea glaciation, and a large area of ​​permafrost. In the southern hemisphere, these figures are directly opposite. In the northern hemisphere, the taiga zone occupies a huge area, in the southern hemisphere it has no analogue. Moreover, at latitudes where broad-leaved and mixed forests dominate in the northern hemisphere (~50°), arctic deserts are located on islands in the southern hemisphere. The fauna of the hemispheres is also different. In the southern hemisphere, there are no zones of tundra, forest-tundra, forest-steppe, and deserts of the temperate zone. The fauna of the hemispheres is also different. There are no bactrian camels, walruses, polar bears and many other animals in the southern, but there are, for example, penguins, marsupials and some other animals that are not in the northern hemisphere. In general, differences in the species composition of plants and animals between the hemispheres are very significant.

These are the basic laws of the geographic shell, some of them are sometimes called laws. However, as D. L. Armand convincingly proved, physical geography does not deal with laws, but with regularities - steadily repeating relationships between phenomena in nature, but having a lower rank than laws.

rice. 150. Generalized structure of altitudinal zonality of landscapes in different geographical zones (according to Ryabchikov A.A.)

Describing the geographic shell, it is necessary to emphasize once again that it is closely connected with the outer space surrounding it and with the internal parts of the Earth. First of all, it receives the energy it needs from the Cosmos. The forces of attraction keep the Earth in orbit around the Sun and cause periodic tidal disturbances in the body of the planet. Corpuscular streams (“solar wind”), X-rays and ultraviolet rays, radio waves and visible radiant energy are directed towards the Earth from the Sun. Cosmic rays are directed from the depths of the Universe towards the Earth. The streams of these rays and particles cause the formation of magnetic storms, auroras, air ionization and other phenomena near the Earth. The mass of the Earth is constantly increasing due to the fall of meteorites and cosmic dust. But the Earth perceives the impact of the Cosmos non-passively. Around the Earth as a planet with a magnetic field and radiation belts, a specific natural system is being created, which is called geographic space. It extends from the magnetopause - the upper boundary of the Earth's magnetic field, which is located at a height of at least 10 Earth radii, to the lower boundary of the Earth's crust - the so-called Mohorovichich (Moho) surface. Geographical space is divided into four parts (from top to bottom):

Near space. Its lower boundary runs along the upper boundary of the atmosphere at an altitude of 1500 - 2000 km above the Earth. Here the main interaction of cosmic factors with the magnetic and gravitational fields of the Earth takes place. Here the corpuscular radiation of the Cosmos, which is detrimental to living organisms, is retained.

High atmosphere. It is bounded below by the stratopause, which this case is also taken as the upper boundary of the geographic envelope. Here, primary cosmic rays slow down, they are transformed, and the thermosphere is heated.

Geographic cover. Its lower boundary is the base of the weathering crust in the lithosphere.

Underlying bark. The lower boundary is the Moho surface. This is the area of ​​manifestation of endogenous factors that form the primary relief of the planet.

The concept of geographical space specifies the position of the geographic envelope of our planet.

In conclusion, we note that a person in the course of his economic activity currently has a great influence on the geographical envelope.

Components of the geographic envelope and their interaction.

Atmosphere, lithosphere, hydrosphere and biosphere - the four shells of the globe are in complex interaction, interpenetrate each other. Together they make up geographical envelope.

Life develops in the geographical shell, the activity of water, ice, wind manifests itself, soils, sedimentary rocks are formed.

The geographic envelope is an area of ​​complex interpenetration, interaction of cosmic and terrestrial forces. It continues to develop and become more complex as a result of the interaction of animate and inanimate nature.

The upper boundary of the geographic shell corresponds to the tropopause - the transitional layer between the troposphere and the stratosphere. Above the equator, this layer is located at an altitude of 16-18 km, and at the poles - 8-10 km. At these heights, the processes generated by the interaction of the geospheres fade and stop. There is practically no water vapor in the stratosphere, there is no vertical movement of air, and temperature changes are not associated with the influence of the earth's surface. Life is impossible here.

The lower boundary on land runs at a depth of 3-5 km, i.e., where the composition and properties of rocks change, there is no liquid water and living organisms.

The geographic shell of the Earth is an integral material system, qualitatively different from other geospheres of the Earth. Its integrity is determined by the continuous interaction of solid, liquid and gaseous, and with the emergence of life - and living substances. All components of the geographic shell interact using the solar energy coming to the Earth and the energy of the Earth's internal forces.

The interaction between the geospheres of the Earth within the geographic envelope occurs as a result of the circulation of substances (water, carbon, oxygen, nitrogen, carbon dioxide and etc.).

All components of the geographic envelope are in complex relationships. A change in one component necessarily causes a change in others.

Rhythm of phenomena in the geographical shell. The geographic envelope of the Earth is constantly changing, the relationship between its individual components is becoming more complicated. These changes occur in time and space. In nature, there are rhythms of different duration. Short, diurnal and annual rhythms are especially important for living organisms. Their periods of rest and activity are consistent with these rhythms. circadian rhythm(change of day and night) is due to the rotation of the Earth around its axis; annual rhythm(change of seasons) - the revolution of the Earth around the Sun. The annual rhythm is manifested in the existence of periods of rest and vegetation in plants, in molting and migration of animals, in some cases - in hibernation, reproduction. The annual rhythm in the geographical envelope depends on the latitude of places: in equatorial latitudes it is less pronounced than in temperate or polar ones.

Daily rhythms proceed against the background of annual ones, annual ones - against the background of long-term ones. There are also age-old, long-term rhythms, such as climate change (cooling - warming, desiccation - moistening).

Changes in the geographical envelope also occur as a result of the movement of the continents, the advance and retreat of the seas, in the course of geological processes: during erosion and accumulation, the work of the sea, volcanism. On the whole, the geographical shell is developing progressively: from the simple to the complex, from the lowest to the highest.

Zoning and sectoring of the geographic envelope.

The most important structural feature of the geographic envelope is its zoning. Zoning law was formulated by the great Russian natural scientist V.V. Dokuchaev, who wrote that the location of our planet relative to the Sun, its rotation and sphericity affect the climate, vegetation and animals, which are distributed over the earth's surface in the direction from north to south in a strictly defined order .

Zoning is better expressed in the vast plains. However, the boundaries of geographical zones rarely coincide with parallels. The fact is that the distribution of zones is influenced by many other natural factors(for example, relief). Significant differences can be observed within the zone. This is explained by the fact that zonal processes are superimposed on azonal processes due to internal factors, not subject to the laws of zoning (relief, distribution of land and water).

The largest zonal divisions of the geographic envelope - geographic zones, they are distinguished according to the radiation balance (arrival-expenditure of solar radiation) and the nature of the general circulation of the atmosphere. The following geographic zones exist on Earth: equatorial, subequatorial (northern and southern), tropical (northern and southern), subtropical (northern and southern), temperate (northern and southern), subpolar (subarctic and subantarctic), polar (arctic and antarctic) .

Geographical belts do not have a regular ring shape, they expand, narrow, bend under the influence of continents and oceans, sea currents, mountain systems.

On the continents and oceans, the geographical zones are qualitatively different. On the oceans, they are well expressed at depths up to 150 m, weakly - up to a depth of 2000 m.

Under the influence of the oceans on the continents within the geographical zones are formed longitudinal sectors(in temperate, subtropical and tropical belts), oceanic and continental.

On the plains within geographical zones, they distinguish natural areas(Fig. 45). In the continental sector of the temperate zone within the East European Plain, these are zones of forests, forest-steppes, steppes, semi-deserts, and deserts. Natural zones are called subdivisions of the earth's surface, characterized by similar soil-plant and climatic conditions. The main factor in the formation of soil and vegetation cover is the ratio of temperatures and moisture.

Rice. 45. The main biozones of the Earth

Vertical explanation. Vertically, natural components change at a different rate than horizontally. When climbing up in the mountains, the amount of precipitation and the light regime change. The same phenomena are expressed in a different way on the plain. The different exposure of the slopes is the reason for the unequal distribution of temperature, moisture, and soil and vegetation cover. The causes of latitudinal zonality and vertical zonality are different: zonality depends on the angle of incidence of the sun's rays and the ratio of heat and moisture; vertical zonality - from a decrease in temperature with height and degree of moisture.

Almost every mountainous country on Earth has its own peculiarities of vertical zonality. In many mountainous countries, the mountain tundra belt falls out and is replaced by a belt of mountain meadows.

Rice. 46. Vegetation change depending on the latitude and altitude of the area

The altitudinal zonality begins from the zone located at the foot of the mountain (Fig. 46). The most important factor in the distribution of belt heights is the degree of moisture.

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§ 40. Circulation of matter and energy in the biosphere§ 42. Natural areas of Russia

Questions before paragraph

1. What geospheres did you study?

In total, the planet Earth has four geospheres - this is the atmosphere, lithosphere, hydrosphere and lithosphere. But some scientists began to distinguish also the earth's crust, mantle and core of the Earth.

The atmosphere is the entire air envelope of the Earth.

Lithosphere - the sphere includes the earth's crust and the surface of the mantle.

The hydrosphere is the entire water part of the Earth, all oceans, seas, rivers and lakes.

Biosphere - the totality of all life on Earth, people, animals, birds, fish, bacteria, viruses.

2. What substances make up the shells of the Earth?

The atmosphere is the air-filled shell of the earth. The atmosphere contains nitrogen, oxygen, ozone, and carbon dioxide. Helium, hydrogen and inert gases are contained in the atmosphere in the smallest fractions of a percent. Lithosphere - hard shell. All known substances can be found in the lithosphere, from rock to gold and silver. The hydrosphere is made up of water. It occupies 70% of the planet's surface. The biosphere consists of living beings and is in close interaction with the hydrosphere and atmosphere. Also contains organic matter.

3. Where are the boundaries of the earth's shells located?

The geographic shells of the Earth are systems of the planet, where all the components inside are interconnected and determined relative to each other. There are four types of shells - atmosphere, lithosphere, hydrosphere and biosphere.

The first is the atmosphere, its outer shell. It borders five layers: the troposphere (8-15 km high), the stratosphere (the custodian of the ozone layer), the mesosphere, the ionosphere and the uppermost - the exosphere. The second of the shells can be attributed to the lithosphere. The earth's crust consists of it, therefore it is considered a hard shell of the Earth. Water is the hydrosphere. By area it makes up 70% of the Earth and includes all the waters of the planet. Thanks to living organisms, there is another one - the biosphere. Its boundaries: land, soil, hydrosphere and lower atmosphere.

4. What cycles of substances can you tell about?

What is the circulation of substances, you can consider an example. The simplest of them is the transformation of organic substances. Initially, all multicellular living beings consist of them. After completing their life cycle, their bodies are decomposed by special organisms, and organic compounds converted to inorganic. After these compounds are absorbed by other beings and inside their bodies are again restored to organic form. Then the process repeats and continues cyclically all the time. The circulation of substances is carried out with a continuous flow (flow) of the external energy of the Sun and the internal energy of the Earth. Depending on the driving force, with a certain degree of conventionality, within the circulation of substances, one can distinguish geological, biological and anthropogenic cycles.

5. Give examples of the influence of climate on flora and fauna.

Climate has a key influence on the development of ecosystems. For example, in deserts or in land areas located beyond the Arctic Circle, climatic conditions extremely unfavorable for the development of living beings, which determines the meager biodiversity. As reverse example equatorial territories can be cited, where a comfortable temperature and a sufficient amount of moisture are maintained all year round, which leads to the rapid development and prosperity of the plant and animal worlds.

6. What influence does a person have on the shells of the Earth?

Huge and, unfortunately, negative. We can say that the activity of people has a direct impact on our entire planet, on all its shells. People change landscapes at their discretion (lithosphere), cut down forests, which also leads to changes on the earth's surface. Without the "support" of the roots, the soil is not protected from the wind, and its top layer simply blows away over time. People drain rivers, create reservoirs and extract minerals from the bowels of the planet. People pollute water and air shell which also affects the biosphere.

Questions and tasks

1. Give examples of the relationship between the geospheres of the Earth.

The interaction of the Earth's geospheres consists in the mutual exchange of matter and the mutual influence of the dynamics of their environments. The movement of air masses in the atmosphere affects the movement of water in the hydrosphere. The liquid substance of the mantle penetrates into the earth's crust and the exchange of substances between the mantle and the earth's crust takes place. The biosphere supplies oxygen to the atmosphere. The hydrosphere is water vapor. The atmosphere protects the organic world and the hydrosphere from the sun by retaining moisture and returning it to the earth in the form of precipitation.

2. Define the concept of "geographical shell" and name its main properties.

The geographic shell is a set of interactions of such planetary layers as: lithosphere and hydrosphere, atmosphere and biosphere. The biosphere through photosynthesis affects the atmosphere. The atmosphere helps the soil not to overheat. The biosphere, in turn, affects the hydrosphere (organisms affect the salinity of the oceans and seas). A change in any of the shells entails a change in the others. So the increase in land area during the great glaciation led to a cooling of the climate, and as a result, North America and northern part Eurasia covered with ice and snow. This modified the flora and fauna, as well as the soil.

3. Within what limits is the distribution of the geographic envelope considered?

The boundaries of the geographic shell are still not clearly defined. For its upper limit, scientists usually take the ozone screen in the atmosphere, beyond which life on our planet does not go. The lower boundary is most often drawn in the lithosphere at depths of no more than 1000 m. This is the upper part of the earth's crust, which is formed under the strong joint influence of the atmosphere, hydrosphere and living organisms. The entire water column of the World Ocean is inhabited, therefore, if we talk about the lower boundary of the geographic shell in the ocean, then it should be drawn along the ocean floor. In general, the geographic envelope of our planet has a total thickness of about 30 km.

4. What is the structure of the geographic shell?

The geographic envelope is a complex formation resulting from the interaction and interpenetration of the atmosphere, hydrosphere, lithosphere and biosphere.

The hydrosphere and biosphere are completely included in the geographic envelope, while the lithosphere and atmosphere are only partially included (the lithosphere in its upper part, and the atmosphere in its lower part). The interaction of geospheres in the geographic shell occurs under the influence of the energy of the Sun and the internal energy of the Earth.

5. In what part of the world and in what natural conditions did the ancestors of modern man appear?

Man appeared, as scientists suggest, in the peculiar natural conditions of global climate change about 2.6 million years ago in East Africa. Therefore, it is considered the ancestral home of mankind. Deciphering the human genome allowed scientists to make a surprising conclusion. It turns out that all people are distant relatives. We all come from one small tribe.

6. Indicate on the map of the hemispheres in which directions the land was settled by humans.

Today, all habitable land areas are inhabited by humans. But it was not always so. The finds of the last decades show that the areas where a person stood out as Homo sapiens were the eastern and central regions of Africa, Western Asia, South-Eastern Europe. In the future, man gradually settled on the territory of the Earth. Approximately 30 thousand years ago, people settled in the northern regions of Europe, Southeast and Northeast Asia, from where, during periods of sharp expansion of the area of ​​glaciers, they penetrated into New World, to Australia and New Guinea. About 10 thousand years ago, having traveled all over America, man reached Tierra del Fuego.

7. Define the concept of "race".

A race is a historically formed human population, characterized by certain biological traits that appear externally: the shape of the eyes, skin color, hair structure, and so on. Traditionally, humanity is divided into three main races: Mongoloid, Caucasoid and Negroid.

- this is a complex shell of the globe, where they touch and mutually penetrate and interact with each other, and. the shell within its boundaries almost coincides with the biosphere.

Mutual penetration into each other of the gas, water, living and shells that make up the geographic shell of the Earth and their interaction determines the integrity of the geographic shell. It is a continuous circulation and exchange of matter and energy. Each shell of the Earth, developing according to its own laws, experiences the influence of other shells and, in turn, exerts its influence on them.

The influence of the biosphere on the atmosphere is associated with photosynthesis, as a result of which there is an intensive gas exchange between them and the regulation of gases in the atmosphere. Plants absorb carbon dioxide from the atmosphere and release oxygen into it, which is necessary for the respiration of all living beings. Thanks to the atmosphere, the surface of the Earth does not overheat during the day sunbeams and does not cool too much at night, which creates conditions for the existence of living individuals. The biosphere also affects the hydrosphere, since organisms have a significant impact on. They take from the water the substances they need, especially calcium, to build skeletons, shells, shells. For many creatures, the hydrosphere is an environment for existence, and water is essential for many life processes of plants and animals. The impact of organisms on is especially noticeable in its upper part. It accumulates the remains of dead plants and animals, are formed of organic origin. Organisms are involved not only in the formation of rocks, but also in their destruction - in: They secrete acids that act on rocks, destroy them with roots penetrating into cracks. Dense, hard rocks turn into loose sedimentary (gravel, pebbles).

Conditions for education are being prepared. Rocks appeared in the lithosphere, which began to be used by man. Knowledge of the law of the integrity of the geographic envelope is of great practical importance. If a person's economic activity does not take it into account, then it often leads to undesirable consequences.

A change in one of the shells of the geographic shell is reflected in all others. An example is the era of the great glaciation in.

The increase in the land surface led to the onset of a colder and, which led to the formation of a layer of snow and ice that covered vast areas in the north and, and this, in turn, led to a change in the flora and fauna and to a change in soils.

The modern geographical envelope is the result of its long development, during which it has continuously become more complex. Scientists distinguish 3 stages of its development.

I stage lasted 3 billion years and was called prebiogenic. During it, only the simplest organisms existed. They took little part in its development and formation. The atmosphere at this stage was characterized by a low content of free oxygen and a high content of carbon dioxide.

II stage lasted about 570 million years. It was characterized by the leading role of living beings in the development and formation of the geographical envelope. living beings provided a huge impact to all its components. There was an accumulation of rocks of organic origin, the composition of water and the atmosphere changed, where the oxygen content increased, since photosynthesis occurred in green plants, and the carbon dioxide content decreased. At the end of this stage, a man appeared.

Stage III- modern. It began 40 thousand years ago and is characterized by the fact that a person begins to actively influence different parts of the geographical envelope. Therefore, it depends on a person whether it will exist at all, since a person on Earth cannot live and develop in isolation from it.

In addition to integrity, the general laws of the geographical shell include its rhythm, that is, the periodicity and repetition of the same phenomena, and.

Geographic zoning manifests itself in a certain change from the poles. The basis of zoning is the different supply of heat and light to the earth's surface, and they are already reflected in all other components, and above all soils, and the animal world.

Zoning is vertical and latitudinal.

Vertical zoning- a regular change in natural complexes both in height and in depth. For mountains, the main reason for this zonality is the change in the amount of moisture with height, and for the depths of the ocean - heat and sunlight. The concept of "vertical zoning" is much broader than "", which is valid only in relation to land. In latitudinal zonality, the largest subdivision of the geographical shell is distinguished -. It is characterized by the generality of temperature conditions. The next step in the division of the geographical shell is the geographical zone. It stands out within the geographical zone not only by the common temperature conditions, but also by moisture, which leads to a commonality of vegetation, soils and wildlife. Within geographic zones (or natural zones), transitional areas are distinguished. They are formed as a result of gradual change

GEOGRAPHICAL SHELL, a genetically and functionally integral shell of the Earth, covering the lower layers of the atmosphere, the upper layers of the earth's crust, the hydrosphere and the biosphere. All these geospheres, penetrating into each other, are in close interaction. The geographic envelope differs from other shells in the presence of life, various kinds energy, as well as increasing and transformative anthropogenic impacts. In this regard, the composition of the geographic shell includes the sociosphere, technosphere, and also the noosphere. The geographic shell has its spatio-temporal structure as a result of natural historical development. The main sources of all processes occurring in the geographic envelope are: the energy of the Sun, which determines the presence of the solar thermal zone, the internal heat of the Earth and gravitational energy. Within the solar thermal zone (with a thickness of several tens of meters), daily and annual temperature fluctuations are determined by the flow of solar energy. The Earth at the upper boundary of the atmosphere receives 10760 MJ/m 2 per year, is reflected from the earth's surface 3160 MJ/m per year, which is several thousand times greater than the heat flux from the Earth's interior to the surface. Uneven receipt and distribution of solar energy over the spherical surface of the Earth leads to a global spatial differentiation of natural conditions (see Geographical zones). The internal heat of the Earth has a significant influence on the formation of the geographic envelope; the influence of endogenous factors is associated with the heterogeneity of the macrostructure of the lithosphere (the emergence and development of continents, mountain systems, vast plains, oceanic depressions, etc.). The boundaries of the geographic envelope are not clearly defined. A number of Russian geographers (A. A. Grigoriev, S. V. Kalesnik, M. M. Ermolaev, K. K. Markov, A. M. Ryabchikov) draw the upper boundary in the stratosphere (at an altitude of 25-30 km, at the level of maximum concentration of the ozone layer), where hard ultraviolet radiation is absorbed, the thermal effect of the earth's surface affects, and living organisms can still exist. Other Russian scientists (D. L. Armand, A. G. Isachenko, F. N. Milkov, Yu. processes in the troposphere with the properties of the underlying surface of the Earth. The lower boundary is often combined (A. G. Isachenko, S. V. Kalesnik, I. M. Zabelin) with the lower limit of the hypergenesis zone (a depth of several hundred meters or more) in the upper part of the lithosphere. A significant part of Russian scientists (D. L. Armand, A. A. Grigoriev, F. N. Milkov, A. M. Ryabchikov, Yu. , the sole of the earth's crust (the border of Mohorovichich). The two types of the earth's crust (continental and oceanic) correspond to different limits of the lower boundary - from 70-80 to 6-10 km. The geographic envelope was formed as a result of a long (4.6 billion years) evolution of the Earth, when varying degrees intensity and significance revealed the main "mechanisms" of planetary processes: volcanism; the formation of mobile belts; buildup and expansion (spreading) of the lithosphere; geomorphological cycle; development of the hydrosphere, atmosphere, vegetation and wildlife; human economic activity, etc. Integral processes are the geological cycle of matter, the biological cycle and moisture circulation. The geographic shell is characterized by a tiered structure with an increase in the density of the substance downwards. The geographical shell is in constant change, and its development and complication proceed unevenly in time and space. The geographical envelope is characterized by the following features:

1. Integrity, due to the continuous exchange of matter and energy between the constituent parts, since the interaction of all components binds them into a single material system, in which a change in even one link entails a conjugate change in all the others.

2. The presence of a number of cycles of matter (and the energy associated with it), which ensure the repetition of the same processes and phenomena. The complexity of cycles is different, among them are mechanical movements (atmospheric circulation, a system of sea surface currents), a change in the aggregate state of matter (moisture cycle) and biochemical transformation (biological cycle).

3. Cyclical (rhythmic) manifestations of many natural processes and phenomena. There is a daily rhythm (change of day and night), annual (change of seasons), intra-secular (cycles of 25-50 years, observed in fluctuations in climate, glaciers, lake levels, river flow, etc.), super-secular (change every 1800-1900 years of the cool-humid climate phase, the dry and warm phase) and the like.

4. The continuity of the development of the geographical envelope and its geographical focus - the landscape sphere of the Earth - occurs under the influence of the interaction of exogenous and endogenous forces. The consequences of this development are:

a) territorial differentiation of the surface of the land, ocean and seabed into areas that differ in internal features and external appearance (landscapes, geocomplexes); special forms of territorial differentiation - geographical zonality and altitudinal zonality of landscapes;

b) significant differences in nature in the Northern and Southern hemispheres, in the distribution of land and sea (the predominant part of the land is in the Northern Hemisphere), climate, composition of flora and fauna, in the nature of landscape zones, etc.;

c) the heterochrony of the development of the geographic envelope, due to the spatial heterogeneity of the nature of the Earth, as a result of which at the same moment different territories are either in different phases of an equally directed evolutionary process, or differ from each other in the direction of development (examples: ancient glaciation in different regions of the Earth began and ended non-simultaneously; in some geographical areas the climate becomes drier, in others at the same time - wetter, etc.).

The idea of ​​a geographic envelope was first approached by the Russian scientists P. I. Brounov (1910) and R. I. Abolin (1914). The term was introduced and substantiated by A. A. Grigoriev (1932). Concepts similar to the geographic shell exist in foreign geography (the “earth shell” by the German scientist A. Getner and the American scientist R. Hartshorne; the “geosphere” by the Austrian geographer G. Karol, etc.), in which it is usually considered not as a natural system, but as a combination of natural and social phenomena.

Lit .: Abolin R.I. Experience of epigenological classification of swamps // Bolotovedenie. 1914. No. 3; Brounov P.I. Course of physical geography. P., 1917; Grigoriev AA Experience of analytical characterization of the composition and structure of the physical-geographical shell of the globe. L.; M., 1937; he is. Patterns of the structure and development of the geographical environment. M., 1966; Markov, K.K., Polar asymmetry of the geographic envelope, Izv. All-Union Geographical Society. 1963. T. 95. Issue. 1; he is. Space and time in geography // Nature. 1965. No. 5; Carol H. Zur Theorie der Geographie // Mitteilungen der Osterreichischen Geographischen Gessellschaft. 1963. Bd 105. N. 1-2; Kalesnik S. V. General geographical patterns of the Earth. M., 1970; Isachenko, A.G., Systems and rhythms of zoning, Izv. All-Union Geographical Society. 1971. T. 103. Issue. 1.

K. N. Dyakonov.

The structure of the geographical shell

The geographic shell is an integral continuous near-surface part of the Earth, within which there is an intense interaction of four components: the lithosphere, hydrosphere, atmosphere and biosphere (living matter). This is the most complex and diverse material system of our planet, which includes the entire hydrosphere, the lower layer of the atmosphere (troposphere), the upper part of the lithosphere and the living organisms inhabiting them. The spatial structure of the geographic envelope is three-dimensional and spherical. This is a zone of active interaction of natural components, in which the greatest manifestation of physical and geographical processes and phenomena is observed.

Geographic envelope boundaries fuzzy. Up and down from the earth's surface, the interaction of the components gradually weakens, and then completely disappears. Therefore, scientists draw the boundaries of the geographical shell in different ways. The upper boundary is often taken to be the ozone layer, located at an altitude of 25 km, where most of the ultraviolet rays that have a detrimental effect on living organisms are retained. However, some researchers conduct it along the upper boundary of the troposphere, which most actively interacts with the earth's surface. The base of the weathering crust up to 1 km thick is usually taken as the lower boundary on land, and the ocean floor in the ocean.

The geographical envelope consists of structural parts - components. These are rocks, water, air, plants, animals and soils.

Section VI geographical envelope and physical-geographical zoning

They differ in physical state (solid, liquid, gaseous), level of organization (non-living, living, bio-inert), chemical composition, activity (inert - rocks, soil, mobile - water, air, active - living matter).

The geographical envelope in the horizontal direction is divided into separate natural complexes, which is determined by the uneven distribution of heat in different parts of the earth's surface and its heterogeneity.

I call natural complexes formed on land territorial, and in the ocean or other body of water - aquatic. The geographic envelope is a natural complex of the highest, planetary rank. On land, it includes smaller natural complexes: continents and oceans, natural zones and such natural formations as the East European Plain, the Sahara Desert, the Amazonian Lowland, etc. The smallest natural territorial complex, in the structure of which all the main components participate, is considered physical-geographical region. It is a block of the earth's crust, connected with all other components of the complex, that is, with water, air, vegetation and wildlife. This block should be sufficiently isolated from neighboring blocks and have its own morphological structure, that is, include parts of the landscape, which are facies, tracts and areas.

The geographical envelope has a peculiar spatial structure. It is three-dimensional and spherical. This is the zone of the most active interaction of natural components, in which the greatest intensity of various physical and geographical processes and phenomena is observed. At some distance up and down from the earth's surface, the interaction of the components weakens, and then completely disappears. This happens gradually and the boundaries of the geographical shell - fuzzy. Therefore, researchers draw its upper and lower boundaries in different ways. The upper boundary is often taken to be the ozone layer, which lies at a height of 25-. This layer absorbs ultraviolet rays, so life is possible below it. However, some researchers draw the boundary of the shell below - along the upper boundary of the troposphere, taking into account that the troposphere most actively interacts with the earth's surface. Therefore, it manifests geographical zonality and zonality.

The lower boundary of the eographic shell is often drawn along the Mohorovichich section, that is, along the asthenosphere, which is the sole of the earth's crust. In more modern works, this boundary is drawn higher and limits from below only a part of the earth's crust, which is directly involved in interaction with water, air, and living organisms. As a result, a weathering crust is created, in the upper part of which there is soil.

The zone of active transformation of mineral matter on land has a thickness of up to several hundred meters, and under the ocean only tens of meters. Sometimes the entire sedimentary layer of the lithosphere is referred to the eographic shell.

Geographer N.A. Solntsev believes that the space of the Earth, where the substance is in liquid, gas and solid, can be attributed to the eographic shell. atomic states, or in the form living matter. Outside this space, matter is in subatomic state, forming an ionized gas of the atmosphere or compacted packages of atoms of the lithosphere.

This corresponds to the boundaries, which have already been mentioned above: the upper boundary of the troposphere, the ozone screen - up, the lower limit of weathering and the lower boundary of the granite layer of the earth's crust - down.

More articles about geographic shell

Lecture: Geographical shell its structure and boundaries.

The geographic shell is an integral continuous near-surface part of the Earth, within which there is an intense interaction of four components: the lithosphere, hydrosphere, atmosphere and biosphere (living matter). This is the most complex and diverse material system of our planet, which includes the entire hydrosphere, the lower layer of the atmosphere (troposphere), the upper part of the lithosphere and the living organisms inhabiting them.

Geographical shell of the Earth

The spatial structure of the geographic envelope is three-dimensional and spherical. This is a zone of active interaction of natural components, in which the greatest manifestation of physical and geographical processes and phenomena is observed.

The boundaries of the geographic envelope are indistinct. Up and down from the earth's surface, the interaction of the components gradually weakens, and then completely disappears. Therefore, scientists draw the boundaries of the geographical shell in different ways. The upper boundary is often taken to be the ozone layer, located at an altitude of 25 km, where most of the ultraviolet rays that have a detrimental effect on living organisms are retained. However, some researchers conduct it along the upper boundary of the troposphere, which most actively interacts with the earth's surface. The base of the weathering crust up to 1 km thick is usually taken as the lower boundary on land, and the ocean floor in the ocean.

The idea of ​​a geographical shell as a special natural formation was formulated at the beginning of the 20th century. A.A. Grigoriev and S.V. Kalesnik. They revealed the main features of the geographic envelope: 1) the complexity of the composition and the diversity of the state of matter; 2) the flow of all physical and geographical processes due to solar (cosmic) and internal (telluric) energy; 3) transformation and partial conservation of all types of energy entering it; 4) the concentration of life and the presence of human society; 5) the presence of a substance in three states of aggregation.

The geographical envelope consists of structural parts - components. These are rocks, water, air, plants, animals and soils. They differ in physical state (solid, liquid, gaseous), level of organization (non-living, living, bio-inert), chemical composition, activity (inert - rocks, soil, mobile - water, air, active - living matter).

The geographical envelope has vertical structure consisting of separate spheres. The lower tier is composed of dense matter of the lithosphere, while the upper ones are represented by lighter matter of the hydrosphere and atmosphere. Such a structure is the result of matter differentiation with the release of dense matter in the center of the Earth, and lighter matter along the periphery. The vertical differentiation of the geographic shell served as the basis for F.N. Milkov to single out a landscape sphere inside it - a thin layer (up to 300 m), where the earth's crust, atmosphere and hydrosphere come into contact and actively interact.

The geographical envelope in the horizontal direction is divided into separate natural complexes, which is determined by the uneven distribution of heat in different parts of the earth's surface and its heterogeneity. I call natural complexes formed on land territorial, and in the ocean or other body of water - aquatic. The geographic envelope is a natural complex of the highest, planetary rank. On land, it includes smaller natural complexes: continents and oceans, natural zones and such natural formations as the East European Plain, the Sahara Desert, the Amazonian Lowland, etc. The smallest natural territorial complex, in the structure of which all the main components participate, is considered physical-geographical region. It is a block of the earth's crust, connected with all other components of the complex, that is, with water, air, vegetation and wildlife. This block should be sufficiently isolated from neighboring blocks and have its own morphological structure, that is, include parts of the landscape, which are facies, tracts and areas.

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Abstract on the topic:

Geographic envelope

Plan:

Introduction
• 1Terminology
• 2Geographic shell components
  • 2.1 Earth's crust
  • 2.2 Troposphere
  • 2.3Stratosphere
  • 2.4Hydrosphere
  • 2.5 Biosphere
  • 2.6 Stratisphere

Notes
Literature

Introduction

Geographical shell- in Russian geographical science, this is understood as an integral and continuous shell of the Earth, where its constituent parts (the earth's crust, troposphere, stratosphere, hydrosphere and biosphere) penetrate each other and are in close interaction. Between them there is a continuous exchange of matter and energy.

The upper boundary of the geographic shell is drawn along the stratopause, since before this boundary the thermal effect of the earth's surface affects atmospheric processes; the boundary of the geographic shell in the lithosphere is often combined with the lower limit of the hypergenesis region (sometimes the foot of the stratisphere, the average depth of seismic or volcanic sources, the sole of the earth's crust, and the level of zero annual temperature amplitudes are taken as the lower boundary of the geographic shell). The geographic envelope completely covers the hydrosphere, descending in the ocean 10-11 km below sea level, the upper zone of the earth's crust and the lower part of the atmosphere (a layer 25-30 km thick). The greatest thickness of the geographical envelope is close to 40 km. In addition, there was a book "Geographical shell" Geographical shell is the object of study of geography and its sciences.

1. Terminology

Despite the criticism of the term "geographical envelope" and the difficulty in defining it, it is actively used in geography and is one of the main concepts in Russian geography.

The concept of the geographic envelope as the "outer sphere of the earth" was introduced by the Russian meteorologist and geographer P. I. Brounov (1910). The modern concept was developed and introduced into the system of geographical sciences by A. A. Grigoriev (1932). The most successful history of the concept and contentious issues considered in the works of I. M. Zabelin.

Concepts similar to the concept of a geographical shell exist in foreign geographical literature ( earthly shell A. Getner and R. Hartshorne, geosphere G.

Geographical envelope, its properties and integrity

Karol and others). However, there the geographical envelope is usually considered not as a natural system, but as a combination of natural and social phenomena.

There are other terrestrial shells at the boundaries of the connection of various geospheres.

2. Components of the geographical envelope

2.1. Earth's crust

The earth's crust is the upper part of the solid earth. It is separated from the mantle by a boundary with a sharp increase in the velocities of seismic waves - the Mohorovichich boundary. The thickness of the crust ranges from 6 km under the ocean to 30-50 km on the continents. There are two types of crust - continental and oceanic. Three geological layers are distinguished in the structure of the continental crust: sedimentary cover, granite and basalt. The oceanic crust is composed mainly of mafic rocks, plus a sedimentary cover. The earth's crust is divided into lithospheric plates of different sizes, moving relative to each other. The kinematics of these movements is described by plate tectonics.

2.2. Troposphere

Its upper limit is at an altitude of 8-10 km in polar, 10-12 km in temperate and 16-18 km in tropical latitudes; lower in winter than in summer. The lower, main layer of the atmosphere. It contains more than 80% of the total mass of atmospheric air and about 90% of all water vapor present in the atmosphere. In the troposphere, turbulence and convection are highly developed, clouds appear, cyclones and anticyclones develop. Temperature decreases with altitude with an average vertical gradient of 0.65°/100 m

Behind " normal conditions» near the Earth's surface, the density is 1.2 kg/m3, barometric pressure is 101.34 kPa, temperature is plus 20 °C, and relative humidity is 50%. These conditional indicators have a purely engineering value.

2.3. Stratosphere

The upper limit is at an altitude of 50-55 km. The temperature rises with altitude up to a level of about 0 °C. Low turbulence, negligible water vapor content, increased ozone content compared to the lower and upper layers (maximum ozone concentration at altitudes of 20-25 km).

2.4. Hydrosphere

The hydrosphere is the totality of all the water reserves of the Earth. Most of the water is concentrated in the ocean, much less - in the continental river network and groundwater. There are also large reserves of water in the atmosphere, in the form of clouds and water vapor.

Part of the water is in a solid state in the form of glaciers, snow cover, and in permafrost, making up the cryosphere.

2.5. Biosphere

The biosphere is a set of parts of the earth's shells (litho-, hydro- and atmosphere), which is inhabited by living organisms, is under their influence and is occupied by the products of their vital activity.

2.6. Stratisphere

Stratisphere - the upper shell of the Earth up to 20 km thick, which has a layered structure and consists of sedimentary and sedimentary-volcanic rocks.

Notes

1. Tanimoto Toshiro Crustal Structure of the Earth - www.agu.org/books/rf/v001/RF001p0214/RF001p0214.pdf / Thomas J. Ahrens. - Washington, DC: American Geophysical Union, 1995. - ISBN ISBN 0-87590-851-9

Literature

• Brounov P. I. Course of physical geography, St. Petersburg, 1917.
• Grigoriev A. A. Experience of the analytical characteristics of the composition and structure of the physical-geographical shell of the globe, L.-M., 1937.
• Grigoriev A. A. Patterns of the structure and development of the geographical environment, M., 1966.

Geographic envelope and its properties. The globe consists of several shells: atmosphere, hydrosphere, lithosphere. In addition, a biosphere inhabited by living organisms is distinguished on Earth. All shells are in close contact and interact with each other.

Geographic envelope (GO)- a single material system within which the lithosphere, hydrosphere, atmosphere and biosphere interact. The geographic envelope includes the upper part of the lithosphere, the lower part of the atmosphere, the entire biosphere, and the entire hydrosphere. As a result of such close interpenetration, processes develop in the geographic envelope that distinguish it from other areas:

1) only in GO is it possible to have a variety of types of energy, the conversion of solar energy in plants (photosynthesis);

2) only in GO is it possible for a substance to exist in three states of aggregation;

3) only GO is characterized by the presence organic matter and life, human society develops.

The main source of energy in the geographic shell is the Sun. Solar radiation on Earth provides all the processes occurring in GO, participates in all cycles of matter. The development of GO has its own patterns and character traits: integrity, rhythm and zoning, cycles of matter and energy.

Cycles of matter and energy: all GO substances are in constant circulation. The water evaporated from the oceans is transported by air currents to land, falls in the form of precipitation and returns to the ocean again by rivers and groundwater - this is how the water cycle closes in nature. The biological cycle consists in the transformation of plants inorganic substances into organic, which, after the death of the biomass, again turn into inorganic. Often the cycles of matter are accompanied by cycles of energy (for example, the release of heat during the condensation of water vapor and the absorption of heat during evaporation). Circulations determine the continuous development of the geographic envelope.

Civil defense integrity It manifests itself in the fact that a change in one component of nature inevitably causes a change in all the others. These changes can evenly cover the entire geographic envelope and are manifested in some of its separate parts, influencing other parts.

Rhythm natural phenomena is the repetition of similar phenomena over time. Examples of rhythm: daily and annual periods of the Earth's rotation; long periods of mountain building and climate change on Earth; periods of change in solar activity. The study of rhythms is important for forecasting the processes and phenomena occurring in the geographic envelope.

Zoning– regular change of all GO components from the equator to the poles.

What is a geographic envelope, and what are its properties?

It is caused by the rotation of the spherical Earth with a certain inclination of the axis of rotation around the Sun. Depending on the geographical latitude solar radiation is distributed zonally and causes a change in climates, soils, vegetation and other components of the geographic envelope. The world law of zonality of the geographical shell is manifested in its division into geographical zones and natural zones. On its basis, the physical-geographical zoning of the Earth and its individual sections is carried out.

Simultaneously with the zonal, there are also azonal factors associated with the internal energy of the Earth (relief, height, configuration of the continents). They violate the zonal distribution of GO components. In any part of the world, zonal and azonal factors act simultaneously.

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