Latitudinal zonality and altitudinal zonation in the geographic envelope. Natural zones of the Earth. Law of latitudinal zoning What is altitudinal zoning

Latitudinal zonality and altitudinal zonality – geographical concepts, characterizing a change in natural conditions, and, as a consequence, a change in natural landscape zones, as one moves from the equator to the poles (latitudinal zonality), or as one rises above sea level.

Latitudinal zonation

It is known that the climate in different parts of our planet is not the same. The most noticeable change in climatic conditions occurs when moving from the equator to the poles: The higher the latitude, the colder the weather becomes. This geographical phenomenon is called latitudinal zoning. It is associated with the uneven distribution of thermal energy from the Sun over the surface of our planet.

Plays a major role in climate change tilt of the earth's axis in relation to the Sun. In addition, latitudinal zonality is associated with different distances of the equatorial and polar parts of the planet from the Sun. However, this factor influences the temperature difference at different latitudes to a much lesser extent than the axis tilt. The Earth's axis of rotation, as is known, is located at a certain angle relative to the ecliptic (the plane of motion of the Sun).

This tilt of the Earth's surface leads to the fact that the sun's rays fall at right angles on the central, equatorial part of the planet. Therefore, it is the equatorial belt that receives maximum solar energy. The closer to the poles, the less the sun's rays warm the earth's surface due to the greater angle of incidence. The higher the latitude, the greater the angle of incidence of the rays, and the more of them are reflected from the surface. They seem to glide along the ground, ricocheting further into outer space.

It should be taken into account that the tilt of the earth's axis relative to the Sun changes throughout the year. This feature is associated with the alternation of seasons: when it is summer in the southern hemisphere, it is winter in the northern hemisphere, and vice versa.

But these seasonal variations do not play a special role in the average annual temperature. In any case, the average temperature in the equatorial or tropical zone will be positive, and in the region of the poles - negative. Latitudinal zoning has direct influence on climate, landscape, fauna, hydrology and so on. When moving towards the poles, the change in latitudinal zones is clearly visible not only on land, but also in the ocean.

In geography, as we move towards the poles, the following latitudinal zones are distinguished:

Equatorial.
Tropical.
Subtropical.
Moderate.
Subarctic.
Arctic (polar).

Altitudinal zone

Altitudinal zonation, just like latitudinal zonation, is characterized by changing climatic conditions. Only this change occurs not when moving from the equator to the poles, but from sea level to the highlands. The main differences between lowland and mountainous areas are the difference in temperature.

Thus, with a rise of one kilometer relative to sea level, the average annual temperature decreases by approximately 6 degrees. In addition, atmospheric pressure decreases, solar radiation becomes more intense, and the air becomes more rarefied, cleaner and less saturated oxygen.

When an altitude of several kilometers (2-4 km) is reached, air humidity increases and the amount of precipitation increases. Further, as you climb the mountains, the change in natural zones becomes more noticeable. To some extent, this change is similar to the change in landscape with latitudinal zonation. The amount of solar heat loss increases with increasing altitude. The reason for this is the lower density of air, which plays the role of a kind of blanket that blocks the sun's rays reflected from the earth and water.

At the same time, the change in altitudinal zones does not always occur in a strictly defined sequence. This change may occur differently in different geographic areas. In tropical or arctic regions, the full cycle of changes in altitudinal zones may not be observed at all. For example, in the mountains of Antarctica or the Arctic region there are no forest belts or alpine meadows. And in many mountains located in the tropics there is a snow-glacier (nival) belt. The most complete change of cycles can be observed in the highest mountain ranges on the equator and in the tropics - in the Himalayas, Tibet, the Andes, and the Cordillera.

Altitudinal zones are divided into several types, starting from the very top to the bottom:

Nival belt. This name comes from the Latin “nivas” - snowy. This is the highest altitude zone, characterized by the presence of eternal snow and glaciers. In the tropics it begins at an altitude of at least 6.5 km, and in the polar zones - directly from sea level.
Mountain tundra. It is located between the belt of eternal snow and alpine meadows. In this zone, the average annual temperature is 0-5 degrees. The vegetation is represented by mosses and lichens.
Alpine meadows. Located below the mountain tundra, the climate is temperate. The flora is represented by creeping shrubs and alpine herbs. They are used in summer transhumance for grazing sheep, goats, yaks and other mountain domestic animals.
Subalpine zone. It is characterized by a mixture of alpine meadows with rare mountain forests and shrubs. It is a transition zone between high mountain meadows and forest belt.
Mountain forests. The lower belt of mountains, with a predominance of a wide variety of tree landscapes. Trees can be either deciduous or coniferous. In the equatorial-tropical zone, the bases of the mountains are often covered with evergreen forests - jungles.

Latitudinal zoning is a natural change in physical-geographical processes, components and complexes of geosystems from the equator to the poles. The primary cause of zonality is the uneven distribution of solar energy over latitude due to the spherical shape of the Earth and changes in the angle of incidence of solar rays on the earth's surface. In addition, latitudinal zonality also depends on the distance to the Sun, and the mass of the Earth affects the ability to retain the atmosphere, which serves as a transformer and redistributor of energy. Zoning is expressed not only in the average annual amount of heat and moisture, but also in intra-annual changes. Climatic zonation is reflected in the runoff and hydrological regime, the formation of weathering crust, and waterlogging. It has a great influence on the organic world and specific relief forms. The homogeneous composition and high air mobility smooth out zonal differences with height.

Altitudinal zonality, altitudinal zonality is a natural change in natural conditions and landscapes in the mountains as the absolute height (altitude above sea level) increases.

An altitudinal zone, an altitudinal landscape zone, is a unit of altitudinal-zonal division of landscapes in the mountains. The altitudinal belt forms a strip that is relatively uniform in natural conditions, often intermittent[

Altitudinal zonation is explained by climate change with altitude: per 1 km of ascent, the air temperature decreases by an average of 6 °C, air pressure and dust levels decrease, the intensity of solar radiation increases, and up to an altitude of 2-3 km, cloudiness and precipitation increase. As altitude increases, landscape zones change, somewhat similar to latitudinal zonality. The amount of solar radiation increases along with the radiation balance of the surface. As a result, the air temperature decreases as altitude increases. In addition, there is a decrease in precipitation due to the barrier effect.

GEOGRAPHICAL ZONES (Greek zone - belt) - wide stripes on the earth's surface, limited by similar features of hydroclimatic (energy-producing) and biogenic (life-food) natural resources.

Zones are part of geographical zones, but encircle the land globe only those in which excess air and soil moisture remains throughout the entire belt. These are landscape zones of tundra, tundra forests and taiga. All other zones within the same geographic latitude change when the oceanic influence weakens, that is, when the ratio of heat and moisture—the main landscape-forming factor—changes. For example, in the zone of 40-50° northern latitude in both North America and Eurasia, zones of broad-leaved forests turn into mixed forests, then into coniferous ones, and deeper into the continents they are replaced by forest-steppes, steppes, semi-deserts and even deserts. Longitudinal zones or sectors arise.

Latitudinal zonation— a natural change in physical-geographical processes, components and complexes of geosystems from the equator to the poles.

The primary cause of zonality is the uneven dispersion of solar energy over latitude due to the spherical shape of the Earth and changes in the angle of incidence of solar rays on the earth's surface. In addition, latitudinal zonality also depends on the distance to the Sun, and the mass of the Earth affects the ability to retain the atmosphere, which serves as a transformer and redistributor of energy.

The inclination of the axis to the ecliptic plane is of great importance; the unevenness of the solar heat supply across seasons depends on this, and the daily rotation of the planet causes the deviation of air masses. The result of differences in the distribution of radiant energy from the Sun is the zonal radiation balance of the earth's surface. The unevenness of heat supply affects the distribution of air masses, moisture circulation and atmospheric circulation.

Zoning is expressed not only in the average annual amount of heat and water, but also in intra-annual configurations. Climatic zonation is reflected in the runoff and hydrological regime, the formation of weathering crust, and waterlogging. There is a huge impact on the organic world and special relief forms. The homogeneous composition and high air mobility smooth out zonal differences with height.

There are 7 circulation zones in each hemisphere.

Vertical zonality is also related to the amount of heat, but it only depends on the altitude above sea level. As you climb the mountains, the climate, soil class, vegetation and fauna change. It is curious that even in hot countries it is possible to encounter landscapes of the tundra and even an icy desert. However, in order to see this, you will have to climb high into the mountains. Thus, in the tropical and equatorial zones of the Andes of South America and in the Himalayas, landscapes alternately change from wet rain forests to alpine meadows and a zone of endless glaciers and snow.

It cannot be said that the altitudinal zone completely repeats the latitudinal geographical zones, since many conditions are not repeated in the mountains and plains. The range of altitudinal zones near the equator is more diverse, for example on the highest peaks of Africa, Mount Kilimanjaro, Kenya, Margherita Peak, South America on the slopes of the Andes.

Primary sources:

pzemlia.ru - what is zoning;

ru.wikipedia.org - about zoning;

tropicislands.ru - latitudinal zonation.

What is latitudinal zonation?

I can show with an example what latitudinal zoning is, because there is nothing simpler! As far as I remember, we all should have covered this topic in the 7th or certainly in the 8th grade during a geography lesson. It's never too late to revive memories, and you'll see for yourself how easy it is!

The simplest example of latitudinal zoning

Last May, I was in Barnaul with a friend, and we noticed birch trees with young leaves. And in general there was a lot of green vegetation around. When we returned to Pankrushikha (Altai Territory), we saw that the birch trees in this village had just begun to bloom! But Pankrushikha is only about 300 km away from Barnaul.

Having made simple calculations, we found out that our village is only 53.5 km north of Barnaul, but the difference in the speed of vegetation can be seen even with the naked eye! It would seem that such a small distance between settlements, but the lag in leaf growth is approximately 2 weeks.

The sun and latitudinal zonality

Our globe has latitude and longitude - this is what scientists have agreed upon. At different latitudes, heat is distributed unevenly, this leads to the formation of natural zones that differ in the following:

climate;
diversity of animals and plants;
humidity and other factors.

It is easy to understand what wide zoning is if you take into account 2 facts. The Earth is a sphere, and therefore the sun's rays cannot illuminate its surface evenly. Closer to north pole The angle of incidence of the rays becomes so small that permafrost can be observed.

Zoning of the underwater world

Few people know about this, but zonation is also present in the ocean. At a depth of approximately two kilometers, scientists were able to record changes in natural zones, but the ideal depth for study is no more than 150 m. Changes in zones are manifested in the degree of salinity of water, temperature fluctuations, and the variety of marine fish and other organic creatures. Interestingly, the belts in the ocean are not much different from those on the surface of the Earth!

Latitudinal (geographical, landscape) zoning means a natural change in physical-geographical processes, components and complexes (geosystems) from the equator to the poles.

The belt distribution of solar heat on the earth's surface determines uneven heating (and density) atmospheric air. The lower layers of the atmosphere (troposphere) in the tropics are heated strongly by the underlying surface, and in the subpolar latitudes they are weakly heated. Therefore, above the poles (up to a height of 4 km) there are areas with high pressure, and near the equator (up to 8-10 km) there is a warm ring with low pressure. With the exception of subpolar and equatorial latitudes, westerly air transport predominates throughout the rest of the space.

The most important consequences of the uneven latitudinal distribution of heat are the zonality of air masses, atmospheric circulation and moisture circulation. Under the influence of uneven heating, as well as evaporation from the underlying surface, air masses are formed that differ in their temperature properties, moisture content and density.

There are four main zonal types of air masses:

1. Equatorial (warm and humid);

2. Tropical (warm and dry);

3. Boreal, or temperate latitude masses (cool and wet);

4. Arctic, and in the southern hemisphere Antarctic (cold and relatively dry).

Uneven heating and, as a result, different densities of air masses (different atmospheric pressure) cause a violation of thermodynamic equilibrium in the troposphere and the movement (circulation) of air masses.

As a result of the deflecting effect of the Earth's rotation, several circulation zones are formed in the troposphere. The main ones correspond to four zonal types of air masses, so there are four of them in each hemisphere:

1. Equatorial zone, common to the northern and southern hemispheres (low pressure, calms, rising air currents);

2. Tropical (high pressure, easterly winds);

3. Moderate (low pressure, westerly winds);

4. Polar (low pressure, easterly winds).

In addition, three transition zones are distinguished:

1. Subarctic;

2. Subtropical;

3. Subequatorial.

In transition zones, types of circulation and air masses change seasonally.

The zonality of atmospheric circulation is closely related to the zonality of moisture circulation and humidification. This is clearly manifested in the distribution of precipitation. The zonation of precipitation distribution has its own specificity, a peculiar rhythm: three maxima (the main one at the equator and two minor ones in temperate latitudes) and four minima (in polar and tropical latitudes).

The amount of precipitation in itself does not determine the conditions of moisture or moisture supply of natural processes and the landscape as a whole. In the steppe zone, with 500 mm of annual precipitation, we are talking about insufficient moisture, and in the tundra, with 400 mm, we are talking about excess moisture. To judge moisture, you need to know not only the amount of moisture entering the geosystem annually, but also the amount that is necessary for its optimal functioning. The best indicator of moisture demand is evaporation, i.e., the amount of water that can evaporate from the earth's surface under given climatic conditions, assuming that moisture reserves are unlimited. Volatility is a theoretical value. It should be distinguished from evaporation, i.e. actually evaporating moisture, the amount of which is limited by the amount of precipitation. On land, evaporation is always less than evaporation.

The ratio of annual precipitation to annual evaporation can serve as an indicator of climatic moisture. This indicator was first introduced by G. N. Vysotsky. Back in 1905, he used it to characterize natural areas European Russia. Subsequently, N.N. Ivanov constructed isolines of this ratio, which was called the humidification coefficient (K). The boundaries of landscape zones coincide with certain values of K: in the taiga and tundra it exceeds 1, in the forest-steppe it is 1.0 - 0.6, in the steppe - 0.6 - 0.3, in the semi-desert 0.3 - 0.12, in the desert - less than 0.12.

Zoning is expressed not only in the average annual amount of heat and moisture, but also in their regime, that is, in intra-annual changes. It is well known that the equatorial zone is characterized by the most even temperature regime; four thermal seasons are typical for temperate latitudes, etc. The zonal types of precipitation regimes are varied: in the equatorial zone precipitation falls more or less evenly, but with two maximums; in subequatorial latitudes, summer precipitation is pronounced maximum, in the Mediterranean zone - winter maximum, temperate latitudes are characterized by a uniform distribution with a summer maximum, etc.

Climatic zonation is reflected in all other geographical phenomena - in the processes of runoff and hydrological regime, in the processes of swamping and the formation of groundwater, the formation of weathering crust and soils, in migration chemical elements, V organic world. Zoning is clearly manifested in the surface layer of the ocean (Isachenko, 1991).

Latitudinal zoning is not consistent everywhere - only Russia, Canada and North Africa.

Provinciality

Provinciality refers to changes in the landscape within a geographic zone when moving from the outskirts of the continent to its interior. Provinciality is based on longitudinal and climatic differences as a result of atmospheric circulation. Longitudinal and climatic differences, interacting with the geological and geomorphological features of the territory, are reflected in soils, vegetation and other components of the landscape. The oak forest-steppe of the Russian Plain and the birch forest-steppe of the West Siberian Lowland are an expression of provincial changes in the same forest-steppe type of landscape. The same expression of provincial differences in the forest-steppe type of landscape is the Central Russian Upland, dissected by ravines, and the flat Oka-Don Plain, dotted with aspen bushes. In the system of taxonomic units, provinciality is best revealed through physiographic countries and physiographic provinces.

Sector

A geographic sector is a longitudinal segment of a geographic zone, the unique nature of which is determined by longitudinal-climatic and geological-orographic intra-belt differences.

The landscape and geographical consequences of the continental-oceanic circulation of air masses are extremely diverse. It was noticed that as one moves away from the ocean coasts into the interior of the continents, there is a natural change in plant communities, animal populations, and soil types. The term sectorality is currently accepted. Sectoring is the same general geographical pattern as zoning. There is a certain analogy between them. However, if both heat supply and moisture play an important role in the latitudinal-zonal change of natural phenomena, then the main factor of sectorality is moisture. Heat reserves do not change significantly along longitude, although these changes also play a certain role in the differentiation of physical-geographical processes.

Physiographic sectors are large regional units that extend in a direction close to the meridional and replace one another in longitude. Thus, in Eurasia there are up to seven sectors: humid Atlantic, moderate continental Eastern European, sharply continental East Siberian-Central Asian, monsoon Pacific and three others (mostly transitional). In each sector, zoning acquires its own specificity. In the oceanic sectors, zonal contrasts are smoothed out; they are characterized by a forest spectrum of latitudinal zones from taiga to equatorial forests. The continental spectrum of zones is characterized by the predominant development of deserts, semi-deserts, and steppes. Taiga has special features: permafrost, dominance of light-coniferous larch forests, absence of podzolic soils, etc.