Regularity in the distribution of natural zones on the territory of the earth. Natural zones of the earth Reasons for the formation of natural zones patterns of their placement

The earth's surface and moistening conditions in different parts of the continents natural zones do not form continuous bands parallel to the equator. Only in and on some large plains do they extend in a latitudinal direction, replacing each other from north to south. More often they change in the direction from the coasts of the oceans to the depths of the continents, and sometimes they stretch almost along the meridians.

Natural zones are also formed in: from the equator to the poles, the properties of surface waters, the composition of vegetation and wildlife change. There is also . However, oceanic natural complexes do not have pronounced external differences.

There is great diversity on earth. However, against the background of this diversity, large parts stand out - natural zones and. This is due to the different ratio of heat and moisture that the earth's surface receives.

Formation of natural zones

The uneven distribution of solar heat over the Earth's surface is the main reason for the heterogeneity of the geographic envelope. In almost every land area, the oceanic parts are better moistened than the inland, continental regions. Humidification depends not only on the amount of precipitation, but also on the ratio of heat and moisture. The warmer it is, the more moisture that has fallen with precipitation evaporates. The same amount of precipitation can lead to excessive moisture in one zone and insufficient moisture in another. Thus, the annual precipitation of 200 mm in the cold subarctic zone is excessive (bogs are formed), while in the hot tropical zones it is sharply insufficient (there are deserts).

Due to differences in the amount of solar heat and moisture within geographic zones, natural zones are formed - large areas with uniform temperature and moisture conditions, similar surface and groundwater features, and wildlife.

Features of the natural zones of the continents

In the same natural areas on different continents, vegetation and fauna have similar features.

At the same time, other factors, in addition to climate, also influence the features of the distribution of plants and animals: the geological history of the continents, the relief and features of rocks, and people. The unification and separation of the continents, the change in their relief and climate in the geological past have led to the fact that in similar natural conditions, but on different continents, different species of plants and animals live. The African savannahs, for example, are characterized by antelopes, buffaloes, zebras, African ostriches, and in the South American savannas, several species of deer, armadillos and an ostrich-like flightless nandu bird are common. On each continent there are endemic species (endemics) that are characteristic only of this continent.

Under the influence of human activity, the geographic envelope is undergoing significant changes. To preserve representatives of the organic world and typical natural complexes in all natural zones of the world, specially protected areas are created - nature reserves, etc. In national parks, unlike, nature protection is combined with tourism and people's recreation.

1. Natural complexes are very diverse. Which of them are called natural areas?

The natural complex of land, as well as the complex of the geographic envelope as a whole, is a heterogeneous formation and includes natural complexes of lower ranks, which differ in the quality of the natural components that make up the complex. Such lower ranks are natural areas. Having studied the map of natural zones, you will be able to independently name these natural zones and trace the patterns of their placement.

2. Highlight the main features of the concept of "natural zone".

Each natural zone differs from others in the quality of its constituent soils, flora and fauna. And the quality of these components, in turn, depends on the characteristics of the climate, the totality of the received light, heat and moisture.

3. What are the features of the placement of natural zones on the continents and in the ocean?

The boundaries of natural zones on land are most clearly traced by the nature of the vegetation. It is no coincidence that vegetation is taken as the basis for the name of natural land areas.

Natural zones are also distinguished in the World Ocean, but the boundaries of these zones are less clear, and the division into zones in the ocean is based on the qualitative characteristics of water masses (salinity, temperature, transparency, etc.).

4. What is latitudinal zonality and altitudinal zonality?

The regularity with which natural zones are located on the surface of the Earth is called latitudinal zonality. The change in the quality of the components that make up the natural zone occurs depending on their geographical location, especially on the geographical latitude, on which the amount of heat and moisture received depends.

In the mountains, in contrast to the flat territories, natural zones change with height. The change in natural zones from the foot of mountains to their peaks is similar to the change in natural zones from the equator to the poles. The pattern of changes in natural zones with height in the mountains is called altitudinal zonation or altitudinal zonality.

5. Which mountains have the largest number of altitudinal zones, which have the least? Why?material from the site

The number of natural zones in the mountains depends on the geographical position of the mountains in relation to the equator and on their height. On the southern slopes of the Himalayas, almost all natural zones are replaced: from humid equatorial zones at the foot to arctic deserts at the peaks. In mountains located at higher latitudes, the number of natural zones will be less. Thus, one can trace the relationship that exists between the number of natural zones in the mountains and the geographical position of the mountains in relation to the equator. The reason for this regularity is in the amount of heat and moisture received.

The natural complexes of the Earth are very diverse. These are hot and icy deserts, evergreen forests, endless steppes, bizarre mountains, etc. This diversity is the unique beauty of our planet.

You already know how the natural complexes "mainland" and "ocean" were formed. But the nature of each continent, like each ocean, is not the same. In their territories there are various natural zones.

A natural zone is a large natural complex with a common temperature and moisture conditions, soils, vegetation and wildlife. The formation of zones is due to climate, on land - the ratio of heat and moisture. So, if there is a lot of heat and moisture, that is, high temperatures and a lot of precipitation, a zone of equatorial forests is formed. If the temperatures are high, and there is little precipitation, then a zone of deserts of the tropical belt is formed.

Natural areas of land outwardly differ from each other in the nature of vegetation. Of all the components of nature, the vegetation of the zones most clearly expresses all the most important features of their nature, the relationship between the components. If there are changes in individual components, then outwardly this affects primarily the change in vegetation. The names of the natural zones of the land were received according to the nature of the vegetation, for example, zones of deserts, equatorial forests, etc.

Rice. 33. Natural belts of the oceans

There are also natural zones (natural belts) in the World Ocean. They differ in water masses, organic world, etc. The natural zones of the ocean do not have clear external differences, with the exception of the ice cover, and are named according to their geographical location, like climatic zones (Fig. 33).

Patterns of placement of natural zones on Earth. In the placement of natural zones on the earth's surface, scientists have found a clear pattern, which can be clearly seen on the map of natural zones. To understand this regularity, let us trace the change of natural zones on the map from north to south along 20°E. e. In the subarctic zone, where temperatures are low, there is a zone of tundra and forest-tundra, which gives way to taiga to the south. There is enough heat and moisture for the growth of coniferous trees. In the southern half of the temperate zone, the amount of heat and precipitation increases significantly, which contributes to the formation of a zone of mixed and broad-leaved forests. Somewhat to the east, the amount of precipitation decreases, so the steppe zone is located here.

On the Mediterranean coast in Europe and Africa, the Mediterranean climate dominates with dry summers. It favors the formation of a zone of hard-leaved evergreen forests and shrubs. Then we get into the tropical zone. Here, in the expanses scorched by the sun, it is hot, the vegetation is sparse and stunted, in some places it is completely absent. This is a tropical desert zone. To the south, it is replaced by savannas - tropical forest-steppes, where there is already a wet season of the year and a lot of heat. But the amount of rainfall is not enough for the growth of the forest. In the equatorial climatic zone there is a lot of heat and moisture, therefore a zone of humid equatorial forests with very rich vegetation is formed. In South Africa, zones, like climatic zones, are repeated.

Rice. 34. Blooming steppe is especially beautiful in spring

In Antarctica, there is a zone of the Antarctic desert, characterized by exceptional severity: very low temperatures and strong winds.

So, you, apparently, were convinced that the alternation of natural zones on the plains is explained by a change in climatic conditions - geographical latitude. However, scientists have long noted that natural conditions change not only when moving from north to south, but also from west to east. To confirm this idea, let us follow the map of the change of zones in Eurasia from west to east along the 45th parallel - in the temperate zone.

On the coast of the Atlantic Ocean, where sea air masses coming from the ocean dominate, there is a zone of broad-leaved forests, beech, oak, linden, etc. grow. When moving east, the forest zone is replaced by a zone of forest-steppes and steppes. The reason is the decrease in rainfall. Even farther to the east, precipitation becomes less and the steppes turn into deserts and semi-deserts, which further to the east are again replaced by steppes, and near the Pacific Ocean - by a zone of mixed forests. These coniferous-deciduous forests amaze with their richness and diversity of plant and animal species.

Rice. 35. Due to lack of moisture, plants in the desert do not form a continuous cover.

What explains the alternation of zones at the same latitude? Yes, all the same reasons - a change in the ratio of heat and moisture, which is determined by the proximity or distance from the ocean, the direction of the prevailing winds. There are changes at the same latitudes and in the ocean. They depend on the interaction of the ocean with land, the movement of air masses, currents.

latitudinal zoning. The location of natural zones is closely related to climatic zones. Like climatic zones, they naturally replace each other from the equator to the poles due to a decrease in solar heat entering the Earth's surface and uneven moistening. Such a change in natural zones - large natural complexes is called latitudinal zonality. Zoning is manifested in all natural complexes, regardless of their size, as well as in all components of the geographical envelope. Zoning is the main geographical pattern.

Rice. 36. Coniferous forest

Altitudinal zonation. The change of natural zones, as you know, occurs not only on the plains, but also in the mountains - from the foot to their peaks. With altitude, temperature and pressure decrease, up to a certain height, the amount of precipitation increases, and lighting conditions change. In connection with the change in climatic conditions, there is also a change in natural zones. The zones replacing one another, as it were, encircle mountains at different heights, which is why they are called high-altitude belts. The change of altitudinal belts in the mountains occurs much faster than the change of zones on the plains. It is enough to climb 1 km to be convinced of this.

The first (lower) altitudinal belt of mountains always corresponds to the natural zone in which the mountain is located. So, if the mountain is located in the taiga zone, then when climbing to its top you will find the following altitudinal belts: taiga, mountain tundra, eternal snow. If you have to climb into the Andes near the equator, then you will start your journey from the belt (zone) of equatorial forests. The pattern is as follows: the higher the mountains and the closer they are to the equator, the more altitudinal zones and the more diverse they are. In contrast to zonality on the plains, the alternation of natural zones in the mountains is called altitudinal zonality or altitudinal zonality.

Rice. 37. Savannah in the dry season

The law of geographical zonality also manifests itself in mountainous areas. Some of them we have already considered. The change of day and night, seasonal changes depend on the geographical latitude. If the mountain is near the pole, then there is a polar day and a polar night, a long winter and a short cold summer. In the mountains at the equator, day is always equal to night, there are no seasonal changes.

1. How does a natural complex differ from a geographic envelope?
2. Natural complexes are very diverse. Which of them are called natural areas?
3. Highlight the main features of the concept of "natural zone".
4. What are the features of the location of natural zones on the continents and in the ocean?
5. What is latitudinal zonality and altitudinal zonality?
6. Which mountains have the largest number of altitudinal belts, which have the least? Why?

1) Remember what a natural zone is.

A natural complex is a part of the earth's surface with relatively homogeneous natural conditions.

2) What are the patterns in the placement of natural zones of the Earth?

The location of natural zones is closely related to climatic zones. Like climatic zones, they naturally replace each other from the equator to the poles due to a decrease in solar heat entering the Earth's surface and uneven moistening. Such a change in natural zones - large natural complexes is called latitudinal zonality. The change of natural zones, as you know, occurs not only on the plains, but also in the mountains - from the foot to their peaks. With altitude, temperature and pressure decrease, up to a certain height, the amount of precipitation increases, and lighting conditions change. In connection with the change in climatic conditions, there is also a change in natural zones.

3) What natural zones are located in Eurasia?

Arctic deserts, tundra and forest-tundra, taiga, mixed and broad-leaved forests, forest-steppe and steppe, semi-desert and desert.

4) What sources of geographic information can be used to characterize a natural area?

Observations, geographical maps, meteorological data.

*From the figure, determine how natural areas are located in our country. Why do not all zones extend from the western to the eastern outskirts of the country? What zones are located only in the European part of the country? How can this be explained?

The location of natural zones is closely related to climatic zones. Like climatic zones, they replace each other from the equator to the poles due to a decrease in solar heat entering the Earth's surface and uneven moistening. In Russia, from north to south, the following natural zones replace each other - arctic deserts and semi-deserts, tundra and forest-tundra, taiga, mixed and broad-leaved forests, forest-steppes and steppes, variable-humid forests, deserts and semi-deserts. Not all natural zones extend from the western to the eastern borders of the country. This is due to the fact that Russia has a large latitudinal elongation and climatic conditions change with advancement inland. Only in the European part is there a natural zone of mixed and broad-leaved forests. This can be explained by the fact that in inland areas there is not enough moisture to form forests.

Questions in a paragraph

*There are evergreens in the tundra. How do you explain this fact? Name the representatives of the flora and fauna of the tundra known to you. Consider how they adapt to harsh climates.

There are many evergreens in the tundra. Such plants can use the sunlight as soon as they get out from under the snow, without wasting time and energy on the formation of new foliage. Flora - mosses, lichens, shrubs - crowberry, bearberry, wild rosemary, dwarf birch, willow. Tundra plants have peculiar forms that help them make the best use of the sun's heat and protect themselves from the wind. Pillows form, for example, stemless resin, saxifrage. They are so dense that from a distance they resemble moss-covered stones. The fauna of the tundra is not rich in species, but quantitatively large enough. What animals live in the tundra permanently? The indigenous inhabitants of the tundra include reindeer, lemmings, arctic foxes, wolves, and birds - a snowy owl and a white partridge. Very rare animals - musk oxen.

* Determine on the map which of the largest mineral deposits of our country are located in the tundra zone.

Large industrial hubs have been created in the area of ​​the cities of Nikel, Vorkuta and Norilsk. Non-ferrous metals are being mined in Norilsk, and oil and gas are actively produced in the north of the Tomsk and Tyumen regions. The Arctic tundra zone contains a large supply of important natural resources such as uranium and oil.

Questions at the end of the paragraph

1. What components of nature form a natural zone?

Communities of plants, communities of animals, soils, characteristic features of surface and ground runoff, water regime of rivers, exogenous processes of relief formation.

2. What determines the change of natural zones?

The change of natural zones occurs as a result of a regular change in the ratio of heat and moisture.

3. On the example of our country, justify the pattern of changing natural zones.

On the territory of Russia, there is a change from north to south of the following natural zones: arctic deserts, tundra, forest tundra, taiga, mixed and broad-leaved forests, forest-steppes, steppes, semi-deserts.

4. Think about how the flora and fauna of the Arctic deserts are adapted to their habitat.

Plants do not form a dense vegetation cover, are small, flowering plants have a very short growing season. Animals of the Arctic deserts have adapted to get food from the sea, many have thick white wool, birds inhabit the coast.

5. Indicate the features of the tundra zone of our country and explain them.

A feature of the tundra zone of Russia is its wide distribution and the separation of several subzones in it from north to south. From north to south, three subzones are distinguished: arctic tundras are replaced by typical (moss-lichen), and then by shrubs from dwarf birch and polar willows.

6. Think about the reason for the strong vulnerability of the nature of the tundra zone.

Pollutants do not remain in place, air currents carry them over long distances. And the inhabitants of the tundra, especially lichens, are extremely sensitive to their effects. In the tundra, pollutants accumulate rather than being washed away by meltwater. Low temperatures inhibit the destruction of harmful compounds. Dozens of rivers and lakes perish. Streams of fuel oil and diesel fuel from drilling rigs flow into the soil and water bodies all year round. The coast of the Arctic seas and the entire tundra are littered with ownerless barrels and rusty iron. Many settlements are in an unsanitary state. There are practically no environmentally friendly enterprises. Thermal power stations smoke the sky. Smog settles on white snow, dividing it with black, and patches of bare ground appear in places where pollution is especially high. Not a single plant will grow here for many years. Another problem of the tundra is uncontrolled hunting and poaching. Many plant and animal species have become rare.

The warmth of the sun, clean air and water are the main criteria for life on Earth. Numerous climatic zones led to the division of the territory of all continents and water space into certain natural zones. Some of them, even separated by vast distances, are very similar, others are unique.

Natural areas of the world: what is it?

This definition should be understood as very large natural complexes (in other words, parts of the geographic belt of the Earth), which have similar, uniform climatic conditions. The main characteristic of natural zones is the flora and fauna that inhabits this territory. They are formed as a result of uneven distribution of moisture and heat on the planet.

Table "Natural zones of the world"

natural area	climate zone	Average temperature (winter/summer)
Antarctic and Arctic deserts	Antarctic, arctic	24-70°С /0-32°С
Tundra and forest tundra	Subarctic and Subantarctic	8-40°С/+8+16°С
	Moderate	8-48°C /+8+24°C
mixed forests	Moderate	16-8°С /+16+24°С
broadleaf forests	Moderate	8+8°С /+16+24°С
Steppes and forest-steppes	subtropical and temperate	16+8 °С /+16+24°С
temperate deserts and semi-deserts	Moderate	8-24 °С /+20+24 °С
hardwood forests	Subtropical	8+16 °С/ +20+24 °С
Tropical deserts and semi-deserts	Tropical	8+16 °С/ +20+32 °С
Savannahs and woodlands		20+24°C and above
Variable rainforests	subequatorial, tropical	20+24°C and above
Permanently wet forests	Equatorial	above +24°C

This characteristic of the natural areas of the world is only introductory, because you can talk about each of them for a very long time, all the information will not fit in the framework of one table.

Natural zones of the temperate climate zone

1. Taiga. Surpasses all other natural zones of the world in terms of the area occupied on land (27% of the territory of all forests on the planet). It is characterized by very low winter temperatures. Deciduous trees do not withstand them, so the taiga is dense coniferous forests (mainly pine, spruce, fir, larch). Very large areas of the taiga in Canada and Russia are occupied by permafrost.

2. Mixed forests. Characteristic to a greater extent for the Northern Hemisphere of the Earth. It is a kind of border between the taiga and the broad-leaved forest. They are more resistant to cold and long winters. Tree species: oak, maple, poplar, linden, as well as mountain ash, alder, birch, pine, spruce. As the table "Natural areas of the world" shows, the soils in the zone of mixed forests are gray, not very fertile, but still suitable for growing plants.

3. Broad-leaved forests. They are not adapted to harsh winters and are deciduous. They occupy most of Western Europe, the south of the Far East, the north of China and Japan. Suitable for them is a maritime or temperate continental climate with hot summers and fairly warm winters. As the table "Natural zones of the world" shows, the temperature in them does not fall below -8 ° C even in the cold season. The soil is fertile, rich in humus. The following types of trees are characteristic: ash, chestnut, oak, hornbeam, beech, maple, elm. The forests are very rich in mammals (ungulates, rodents, predators), birds, including commercial ones.

4. Temperate deserts and semi-deserts. Their main distinguishing feature is the almost complete absence of vegetation and sparse wildlife. There are a lot of natural areas of this nature, they are located mainly in the tropics. There are temperate deserts in Eurasia, and they are characterized by sharp temperature changes during the seasons. Animals are represented mainly by reptiles.

Arctic deserts and semi-deserts

They are huge areas of land covered with snow and ice. The map of natural zones of the world clearly shows that they are located on the territory of North America, Antarctica, Greenland and the northern tip of the Eurasian continent. In fact, these are lifeless places, and polar bears, walruses and seals, arctic foxes and lemmings, penguins (in Antarctica) live only along the coast. Where the land is free of ice, lichens and mosses can be seen.

Moist equatorial forests

Their second name is rainforests. They are located mainly in South America, as well as in Africa, Australia and the Greater Sunda Islands. The main condition for their formation is a constant and very high humidity (more than 2000 mm of precipitation per year) and a hot climate (20 ° C and above). They are very rich in vegetation, the forest consists of several tiers and is an impenetrable, dense jungle that has become home to more than 2/3 of all types of creatures that now live on our planet. These rainforests are superior to all other natural areas of the world. Trees remain evergreen, changing foliage gradually and partially. Surprisingly, the soils of moist forests contain little humus.

Natural zones of the equatorial and subtropical climatic zone

1. Variably humid forests, they differ from rainforests in that precipitation falls there only during the rainy season, and during the period of drought that follows it, the trees are forced to shed their leaves. The animal and plant world is also very diverse and rich in species.

2. Savannas and woodlands. They appear where moisture, as a rule, is no longer enough for the growth of variable-humid forests. Their development occurs in the depths of the mainland, where tropical and equatorial air masses dominate, and the rainy season lasts less than six months. They occupy a significant part of the territory of subequatorial Africa, the interior of South America, partly Hindustan and Australia. More detailed information about the location is reflected in the map of natural areas of the world (photo).

hardwood forests

This climate zone is considered the most suitable for human habitation. Hardwood and evergreen forests are located along sea and ocean coasts. Precipitation is not so abundant, but the leaves retain moisture due to a dense leathery shell (oaks, eucalyptus), which prevents them from falling off. In some trees and plants, they are modernized into thorns.

Steppes and forest-steppes

They are characterized by the almost complete absence of woody vegetation, this is due to the meager level of precipitation. But the soils are the most fertile (chernozems), and therefore are actively used by man for agriculture. Steppes occupy large areas in North America and Eurasia. The predominant number of inhabitants are reptiles, rodents and birds. Plants have adapted to the lack of moisture and most often manage to complete their life cycle in a short spring period, when the steppe is covered with a thick carpet of greenery.

Tundra and forest tundra

In this zone, the breath of the Arctic and Antarctic begins to be felt, the climate becomes more severe, and even coniferous trees cannot withstand it. Moisture is in excess, but there is no heat, which leads to swamping of very large areas. There are no trees at all in the tundra, the flora is mainly represented by mosses and lichens. It is believed that this is the most unstable and fragile ecosystem. Due to the active development of gas and oil fields, it is on the verge of an ecological disaster.

All natural areas of the world are very interesting, whether it is a desert that seems completely lifeless at first glance, boundless Arctic ice or thousand-year-old rainforests with boiling life inside.