Slides and text of this presentation

NATURAL ZONING

Geography Grade 7

Geography teacher MOU Tver gymnasium No. 10

(Greek zone - belt), physiographic zone - part geographic zone with uniform climatic conditions.

natural areas take their name from the vegetation inherent in them, and other geographical features. The zones regularly change from the equator to the poles and from the oceans deep into the continents; have similar temperature and moisture conditions, which determine homogeneous soils, vegetation, animal world and other components natural environment. Natural zones are one of the stages of physical-geographical zoning.

They differ water masses, organic world and others. The natural zones of the ocean do not have clear external differences, with the exception of the ice cover, and are named after their geographic location as well as climatic zones.
From a physical-geographical point of view, differences in the nature of the ocean in the horizontal direction are of greatest interest. The greatest differences on a planetary scale are observed in the meridional direction, they are associated with latitudinal zonality.

In the surface layers, the following natural, or physiographic, belts are distinguished:

SP - north polar (arctic); SSP - northern subpolar (subarctic); SU - northern temperate; SST - northern subtropical; ST - northern tropical; E - equatorial; UT - southern tropical; YUST - southern subtropical; YuU - southern temperate; SSP - southern subpolar (subantarctic); UP - south polar (antarctic)

To identify patterns in the location of geographical belts and zones, a group of scientists (A.M. Ryabchikov et al., 1972) built a hypothetical continent, the size of which corresponds to half the land area, the configuration corresponds to its location in latitudes, the surface is a low plain washed by the ocean . The boundaries of belts and zones inscribed on a hypothetical continent reflect their average contours on the plains of real continents, and in place mountainous areas they are brought to the level of this plain. It turned out that the greater distribution of land in the SP causes a strong stretching of the zones in the continental sectors of the northern temperate and subtropical belts. In the SP, these sectors wedge out. AT in general terms the zonality of the SP repeats the zonality of the SP. Majority geographical areas located meridional. Only on the territory of Canada and Russia, mainly in the continental sectors of the temperate and subarctic zones, does latitudinal position zones.

The earth's land is divided into 13 main latitudinal belts: arctic and antarctic, subarctic and subantarctic, northern and southern temperate, northern and southern subtropical, northern and southern tropical, northern and southern subequatorial, equatorial.

The territory around the poles is covered by cold Arctic (in the Southern Hemisphere - Antarctic) deserts.

Subpolar regions of the Earth. From left to right: arctic desert (Greenland), tundra (Yakutia), forest tundra (Khibiny)

They are distinguished by an extremely harsh climate, extensive ice sheets and rocky deserts, undeveloped soils, poverty and monotony of living organisms. Animals Arctic deserts mainly associated with the sea polar bear, pinnipeds, in Antarctica - penguins.

In the Southern Hemisphere, tundra is represented only on some subantarctic islands. Cold climate and soils underlain permafrost, determine the predominance of mosses, lichens, herbaceous plants and shrubs here. To the south, small trees appear (for example, dwarf birch), and the tundra is replaced by forest-tundra. The fauna of the tundra is quite homogeneous and scarce: reindeer, arctic foxes, lemmings and voles, as well as extensive bird colonies. Of the insects, mosquitoes are plentiful. Most vertebrates leave the tundra with the onset of winter (migrating or flying to warmer climes). Near the seas and oceans, the tundra and forest-tundra give way to a zone of oceanic meadows.

Natural zones of temperate zones

First, conifers (taiga), then mixed, and finally, broad-leaved (the southern temperate zone almost completely covers the world's oceans). The temperate forests cover vast territories in Eurasia and North America. The climate here is already much warmer, and the species diversity is several times greater than in the tundra. Dominated on podzolic soils large trees- pine, spruce, cedar, larch, to the south - oak, beech, birch. Among the animals, predatory (wolf, fox, bear, lynx), ungulates (deer, wild boars), songbirds, individual groups insects.

From left to right: taiga (Sayan), broad-leaved forest ( Krasnoyarsk region), steppe (Stavropol), desert (Gobi)

Slide #10

The zone of temperate zones is replaced by the forest-steppe and then the steppe

The climate is getting warmer and drier, and among the soils, chernozems and chestnut soils are most common. Cereals predominate, among animals - rodents, predatory (wolf, fox, weasel), birds of prey (eagle, hawk), reptiles (vipers, snakes), beetles. A large percentage of the steppes is occupied by agricultural land. Steppes are common in the Midwest of the United States, Ukraine, the Volga region and Kazakhstan.

Slide #11

Semi-deserts and deserts (Middle and central Asia, West Side North America, Argentina)

The desert climate is characterized by low rainfall and large daily temperature fluctuations. Reservoirs in deserts, as a rule, are absent; only occasionally cross the desert major rivers(Huanhe, Syr Darya, Amu Darya). The fauna is quite diverse, most of the species are adapted to living in arid conditions.

Slide #12

As you approach the equator, the temperate zone is replaced by the subtropics.

AT coastal strip(North coast mediterranean sea, southern coast of Crimea, Middle East, southeastern United States, extreme south of South Africa, southern and west coast australia, north island New Zealand) evergreen subtropical forests are common; far from the sea there is a forest-steppe (in North America - prairies), steppe and deserts (the latter - in South Australia, on south coast Mediterranean Sea, in Iran and Tibet, northern Mexico and western South Africa). The fauna of the subtropics is characterized by a mixture of temperate and tropical species.

subtropical belts. From left to right: evergreen forest (Abkhazia), prairies (Nebraska), desert (Karakum)

Slide #13

Largely plowed up and used for plantations. Large animals are practically exterminated. Western Hindustan, Eastern Australia, the Parana basin in South America and South Africa are zones of distribution of more arid tropical savannahs and light forests. The most extensive zone of the tropical belt is deserts (Sahara, Arabian Desert, Pakistan, Central Australia, Western California, Kalahari, Namib, Atacama). Huge spaces pebbly, sandy, rocky and saline surfaces are devoid of vegetation here. The animal world is small.

Tropical belts. From left to right: deciduous forest (Costa Rica), veld (South Africa), desert (Namibia)

The warmth of the sun fresh air and water - these are the main criteria for life on Earth. Numerous climatic zones led to the division of the territory of all continents and body of water to certain natural areas. 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 areas is animal and vegetable world 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 cannot withstand them, so the taiga is coniferous dense forests(mainly pine, spruce, fir, larch). Highly large territories taiga in Canada and Russia are occupied by permafrost.

2. Mixed forests. Characteristic in more for northern hemisphere 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. Occupy most Western Europe, south Far East, northern China and Japan. Suitable for them is maritime climate or temperate continental 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. Characteristic the following types trees: 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- practically complete absence 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 northern tip 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 constant and very high humidity (more than 2000 mm of precipitation per year) and 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 soil 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, interior regions 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 have time to make their life cycle for a short spring period, when the steppe is covered with a dense 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. In connection with the active development of gas and oil fields it is on the verge of an ecological catastrophe.

All the natural areas of the world are very interesting, whether it is a seemingly completely lifeless desert, endless arctic ice or millennia-old rainforests teeming with life.

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

The natural complex of land, as well as the complex geographical envelope in general, it is a heterogeneous formation and includes natural complexes of lower ranks, which differ in the quality of the components of the complex natural ingredients. 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 zonality or altitudinal zoning.

5. Which mountains have the largest number altitudinal zones, in which - 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, i.e. 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. The vegetation of the zones of all the components of nature most clearly expresses all key features 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.

There are also natural zones in the World Ocean ( natural belts). 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.

In the placement of natural areas on earth's surface scientists have found a clear pattern that can be clearly seen on the map of natural areas. 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 growth coniferous trees. AT southern half 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 the zone tropical deserts. 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. AT South Africa zones, like climatic zones, are repeated.

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 the change climatic conditions- geographic 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 Atlantic Ocean, where the sea air masses coming from the ocean dominate, there is a zone of broad-leaved forests, beech, oak, linden, etc. grow. When moving to the 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 pass into deserts and semi-deserts, which further to the east are again replaced by steppes, and near Pacific Ocean- zone of mixed forests. These coniferous-deciduous forests amaze with their richness and diversity of plant and animal species.

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 remoteness of 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 air masses, currents.

The placement of natural areas is located in close connection with 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.

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. Temperature and pressure decrease with altitude, certain height rainfall increases, 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.

Law geographic zoning manifests itself in the mountainous regions. Some of them we have already considered. Also from geographical latitude change of day and night, seasonal changes depend. If the mountain is near the pole, then there is a polar day and polar night long winters and short cold summers. In the mountains at the equator, day is always equal to night, there are no seasonal changes.

What determines the formation of natural zones? What natural areas stand out on our planet? You can answer these and some other questions by reading this article.

Natural zoning: the formation of natural zones on the territory

The so-called our planet is the largest natural complex. It is highly heterogeneous, as in a vertical section (which is expressed in vertical zonality), and in the horizontal (latitudinal), which is expressed in the presence of various natural zones on Earth. The formation of natural zones depends on several factors. And in this article we will talk about the latitudinal heterogeneity of the geographic envelope.

This is a component of the geographical shell, which is distinguished by a certain set of natural components with its own characteristics. These components include the following:

• climatic conditions;
• the nature of the relief;
• hydrological network of the territory;
• soil structure;
• organic world.

It should be noted that the formation of natural zones depends on the first component. However, natural areas receive their names, as a rule, according to the nature of their vegetation. After all, flora is the brightest component of any landscape. In other words, vegetation acts as a kind of indicator that reflects the deep (those that are hidden from our eyes) processes of the formation of a natural complex.

It should be noted that the natural area is highest level in the hierarchy of the physical-geographical zoning of the planet.

Factors of natural zoning

We list all the factors in the formation of natural zones on Earth. So, the formation of natural zones depends on the following factors:

1. Climatic features of the territory (this group of factors should include temperature regime, the nature of moisture, as well as the properties of air masses dominating the territory).
2. The general character of the relief ( this criterion, as a rule, affects only the configuration, the boundaries of a particular natural zone).

The formation of natural zones can also be influenced by proximity to the ocean, or the presence of powerful ocean currents off the coast. However, all these factors are secondary. The main root cause of natural zonality is that different parts (belts) of our planet receive unequal amounts of solar heat and moisture.

Natural areas of the world

What natural zones are distinguished today by geographers on the body of our planet? Let's list them from the poles - to the equator:

• Arctic (and Antarctic) deserts.
• Tundra and forest tundra.
• Taiga.
• Broadleaved forest zone.
• Forest-steppe.
• Steppe (or prairie).
• Semi-desert and desert zone.
• Savannah zone.
• Tropical rainforest zone.
• Humid zone (hylaea).
• The zone of rain (monsoon) forests.

If we look at the map of the natural zonality of the planet, we will see that all natural zones are located on it in the form of sublatitudinal belts. That is, these zones, as a rule, extend from west to east. Sometimes this sublatitudinal direction can be violated. The reason for this, as we have already said, is the features of the relief of a particular territory.

It is also worth noting that there are simply no clear boundaries between natural areas (as shown on the map). So, almost each of the zones smoothly "flows" into the neighboring one. At the same time, border "zones" can very often form at the junction. For example, such are semi-desert or forest-steppe zones.

Conclusion

So, we found out that the formation of natural zones depends on many factors. The main ones are the ratio of heat and moisture in a particular area, the properties of the prevailing air masses, the nature of the relief, and so on. The set of these factors is the same for any territory: mainland, country or small area.

Geographers distinguish over a dozen large natural zones on the surface of our planet, which are elongated in the form of belts and replace each other from the equator to the polar latitudes.