Zoning - change in natural components and the natural complex as a whole from the equator to the poles. Zoning is based on the different influx of heat, light, atmospheric precipitation to the Earth, which, in turn, are already reflected in all other components, and above all - soils, vegetation and fauna.

Zoning is typical for both land and the World Ocean.

The largest zonal subdivisions of the geographic envelope are geographic zones. The belts differ from each other primarily in temperature conditions.

The following geographical zones are distinguished: equatorial, subequatorial, tropical, subtropical, temperate, subpolar, polar (Antarctic and Arctic).

Inside the belts on land, natural zones are distinguished, each of which is characterized not only by the same type of temperature conditions and moisture, which leads to a commonality of vegetation, soils and fauna.

Are you already familiar with the zone arctic deserts, tundra, forest zone temperate climatic zone, steppes, deserts, humid and dry subtropics, savannas, humid evergreen equatorial forests.

Transitional areas are distinguished within natural zones. They are formed as a result of a gradual change in climatic conditions. Such transitional zones include, for example, forest-tundra, forest-steppe and semi-desert.

Zoning can be not only latitudinal, but also vertical. Vertical zoning is a natural change in height and depth of natural complexes. For mountains, the main reason for this zoning is the change in temperature and moisture content with height, and for the depths of the ocean, heat and sunlight.

The change of natural zones depending on the height above sea level in mountainous areas is called, as you already know, altitudinal zonality.

It differs from horizontal zoning in the length of the belts and the presence of a belt of alpine and subalpine meadows. The number of belts usually increases in high mountains and closer to the equator.

Natural areas

Natural areas - large divisions geographic envelope with a certain combination of temperature conditions and humidification regime. They are classified mainly by the prevailing type of vegetation and regularly change in the plains from north to south, and in the mountains - from the foothills to the peaks. Natural zones of Russia are shown in Fig. one.

The latitudinal distribution of natural zones on the plains is explained by the supply of unequal amounts of solar heat and moisture to the earth's surface at different latitudes.

The resources of flora and fauna of natural zones are biological resources territory.

Kit altitude zones depends primarily on the latitude at which the mountains are located and what their height is. It should also be noted that, for the most part, the boundaries between the altitudinal zones are not clear-cut.

Let us consider in more detail the features of the placement of natural zones using the example of the territory of our country.

Polar desert

The very north of our country - the islands of the Arctic Ocean - are located in a natural area polar (arctic) deserts. This zone is also called ice zone. The southern border roughly coincides with the 75th parallel. The natural zone is characterized by the dominance of the Arctic air masses. The total solar radiation is 57-67 kcal / cm 2 per year. Snow cover lasts 280-300 days a year.

In winter, the polar night dominates here, which at a latitude of 75 ° N. sh. lasts 98 days.

In summer, even round-the-clock lighting is not able to provide this area with enough warmth. The air temperature rarely rises above 0 ° С, and average temperature July is +5 ° С. Drizzling precipitation can last for several days, but there are practically no thunderstorms and showers. But fogs are frequent.

Rice. 1. Natural zones of Russia

A significant part of the territory is characterized by modern glaciation... There is no continuous vegetation cover. Near-glacial areas of land on which vegetation develops are small. On the placers of pebbles, fragments of basalt and boulders, mosses and crusty lichens "settle". Occasionally there are poppies and saxifrage, which begin to bloom when the snow has barely had time to melt.

The fauna of the Arctic desert is mainly represented by marine life. This is a harp seal, a walrus, ringed seal, sea hare, beluga whale, Harbour porpoise, killer whale.

Varied in northern seas species of baleen whales. Blue and bowhead whales, sei whales, fin whales, humpback whales are rare and endangered species and are listed in the Red Book. Inner side long horny plates that replace whale teeth, split into hairs. This allows the animals to filter a large volume of water, harvesting plankton, which is the basis of their diet.

The polar bear is also a typical representative of the animal world of the polar desert. "Maternity hospitals" for polar bears are located in Franz Josef Land, Novaya Zemlya, about. Wrangel.

In the summer on rocky islands Numerous bird colonies nest: gulls, guillemots, guillemots, auk, etc.

There is practically no permanent population in the polar desert zone. The weather stations operating here monitor the weather and the movement of ice in the ocean. On the islands they hunt Arctic foxes in winter and game birds in summer. Fishing is carried out in the waters of the Arctic Ocean.

Steppe

Steppes extend to the south of the forest-steppe zone. They are distinguished by the absence of forest vegetation. The steppes stretch in a narrow continuous strip in the south of Russia from western borders to Altai. Further to the east, the steppe areas have focal distribution.

The climate of the steppes is moderately continental, but drier than in the zone of forests and forest-steppe. Annual total solar radiation reaches 120 kcal / cm 2. The average January temperature at the start is -2 ° С, and in the east -20 ° С and below. Summer in the steppe is sunny and hot. The average July temperature is 22-23 ° C. The sum of active temperatures is 3500 ° C. Annual precipitation is 250-400 mm. Showers are frequent in summer. The moisture coefficient is less than one (from 0.6 in the north of the zone to 0.3 in the southern steppes). A stable snow cover lasts up to 150 days a year. Thaws often occur in the west of the zone, so the snow cover there is thin and very unstable. The dominant steppe soils are chernozems.

Natural plant communities are represented mainly by perennial, drought and frost-resistant grasses with a powerful root system. These are, first of all, cereals: feather grass, fescue, wheat grass, serpentine, thin-legged, bluegrass. In addition to cereals, there are numerous representatives of forbs: astragalus, sage, carnation - and bulbous perennials, such as tulips.

Composition and structure plant communities change significantly in both latitudinal and meridional direction.

In the European steppes, narrow-leaved grasses form the basis: feather grass, fescue, bluegrass, fescue, thin-legged, etc. There are many brightly blooming forbs. In summer, feather grass sways like waves in the sea, here and there you can see lilac irises. In the more arid southern regions, in addition to cereals, wormwood, breast milk, and cinquefoil are common. There are many tulips in the spring. In the Asian part of the country, tansy and cereals predominate.

Steppe landscapes are fundamentally different from forest landscapes, which determines the originality of the fauna of this natural zone. Typical animals of this zone are rodents (the largest group) and ungulates.

Ungulates are adapted to long-term movements across the endless expanses of the steppes. Due to the thinness of the snow cover vegetable feed also available in winter. Bulbs, tubers, rhizomes play an important role in nutrition. For many animals, plants are also the main source of moisture. Typical representatives of ungulates in the steppes are turs, antelopes, tarpans. However, most of these species were exterminated or pushed southward as a result of human economic activity. Saigas, which were widespread in the past, have survived in some areas.

Of the rodents, the most common are the gopher, vole, jerboa, etc.

Ferret, badger, weasel, fox also live in the steppe.

Of the birds, the bustard, little bustard, partridge, steppe eagle, buzzard, and kestrel are typical of the steppes. However, even these birds are now rare.

There are much more reptiles than in the forest zone. Among them, we single out the steppe viper, snake, common snake, nimble lizard, shitomordnik.

The wealth of the steppes - fertile soil... The thickness of the humus layer of chernozems is more than 1 m. It is not surprising that this natural zone is almost completely developed by man and natural steppe landscapes are preserved only in reserves. In addition to the high natural fertility of chernozems, agriculture is also favored by climatic conditions favorable for horticulture, the cultivation of thermophilic cereals (wheat, corn) and industrial (sugar beets, sunflowers) crops. In connection with the insufficient amount of atmospheric precipitation and frequent droughts, irrigation systems have been built in the steppe zone.

The steppe is a zone of developed animal husbandry. Cattle, horses and poultry are bred here. Conditions for the development of animal husbandry are favorable due to the presence of natural pastures, feed grains, waste from the processing of sunflowers and sugar beets, etc.

Developed in the steppe zone various industries industries: metallurgy, mechanical engineering, food, chemical, textile.

Semi-deserts and deserts

In the southeast of the Russian Plain and on Caspian lowland there are semi-deserts and deserts.

The total solar radiation here reaches 160 kcal / cm 2. The climate is characterized by high air temperatures in summer (+22 - + 24 ° C) and low in winter (-25-30 ° C). Because of this, there is a large annual amplitude temperatures. The sum of active temperatures is 3600 ° C and more. In the zone of semi-deserts and deserts, a small amount of atmospheric precipitation falls: per year, on average, up to 200 mm. In this case, the moisture coefficient is 0.1-0.2.

The rivers located in the semi-desert and desert zones are fed almost exclusively by the spring melting of snow. Most of them flow into lakes or are lost in the sands.

Typical soils of the semi-desert and desert zone are chestnut. The amount of humus in them decreases in the directions from north to south and from west to east (this is primarily due to a gradual increase in the sparseness of vegetation in these directions), therefore, in the north and west, the soils are dark chestnut, and in the south - light chestnut ( the humus content in them is 2-3%). In the depressions of the relief, the soils are saline. There are salt marshes and solonetzes - soils, from the upper layers of which, due to leaching, a significant part of the readily soluble salts is carried away to the lower horizons.

Plants in semi-deserts are usually low, drought-resistant. The semi-deserts of the south of the country are characterized by such plant species as treelike and gnarled hodgepodge, camel thorn, and juzgun. Feather grasses and fescue are dominant on the uplands.

Steppe grasses alternate with spots of wormwood and romantic yarrow.

The deserts of the southern part of the Caspian lowland are the kingdom of semi-shrub polynyas.

For life in conditions of lack of moisture and salinization of the soil, plants have developed a number of adaptations. Solyanka, for example, has hairs and scales that protect them from excessive evaporation and overheating. Others, such as tamariks, kermek, "acquired" special salt-removing glands to remove salts. In many species, the evaporating surface of the leaves has decreased, and their pubescence has occurred.

The growing season for many desert plants is short. They manage to complete the entire development cycle in favorable time year - spring.

Animal world semi-deserts and deserts are poor in comparison with the forest zone. The most common reptiles are lizards, snakes, and turtles. There are many rodents - gerbils, jerboas and poisonous arachnids - scorpions, tarantulas, karakurt. Birds - bustard, little bustard, lark - can be seen not only in the steppes, but also in semi-deserts. Of the most large mammals note the camel, the saiga; there are korsak, wolf.

The delta of the Volga and the Akhtubinskaya floodplain are a special area in the zone of semi-deserts and deserts of Russia. It can be called a green oasis in the middle of a semi-desert. This territory is distinguished by its thickets of reed-reeds (it reaches 4-5 m in height), shrubs and shrubs (including blackberries), intertwined with climbing plants (hops, bindweed). In the backwaters of the Volga delta, there are a lot of algae, white water lilies (including the Caspian rose and water walnut preserved from the preglacial period). There are many birds among these plants, among which herons, pelicans and even flamingos stand out.

The traditional occupation of the population in the semi-desert and desert zone is cattle breeding: sheep, camels, and cattle are raised. As a result of overgrazing, the area of ​​unsecured scattered sand increases. One of the measures to combat the advance of the desert - phytomelioration - a set of measures for the cultivation and maintenance of natural vegetation. For fixing the dunes, such plant species as giant spikelet, Siberian wheatgrass, saxaul can be used.

Tundra

The vast expanses of the Arctic Ocean coastline from the Kola Peninsula to the Chukchi Peninsula are occupied tundra. The southern border of its distribution is practically owls
e falls by the July isotherm of 10 ° C. Furthest north southern border tundra moved to Siberia - north of 72 ° N latitude. On the Far East the influence of cold seas has led to the fact that the border of the tundra reaches almost the latitude of St. Petersburg.

The tundra receives more heat than the polar desert zone. The total solar radiation is 70-80 kcal / cm 2 per year. However, the climate here continues to be characterized by low temperatures air, short summer, harsh winter... The average air temperature in January reaches -36 ° С (in Siberia). Winter lasts 8-9 months. At this time of the year, southerly winds blowing from the mainland prevail here. Summer is distinguished by an abundance of sunlight, unstable weather: strong northerly winds often blow, bringing cooling and precipitation (especially in the second half of summer, there are often heavy drizzling rains). The sum of active temperatures is only 400-500 ° C. The average annual rainfall reaches 400 mm. Snow cover lasts 200-270 days a year.

The prevailing types of soils in this zone are peat-bog and slightly podzolic. Due to the spread of permafrost, which has a water-resistant property, there are many swamps here.

Since the tundra zone has a significant length from north to south, within its limits climatic conditions change markedly: from severe in the north to more moderate in the south. In accordance with this, the arctic, northern, they are also typical, and southern tundras are distinguished.

Arctic tundra occupy mainly the arctic islands. The vegetation is dominated by mosses, lichens, flowering plants are found, in comparison with the arctic deserts there are more of them. Flowering plants are represented by shrubs and perennial grasses. Common willow and creeping willow, dryad (partridge grass). Of the perennial grasses, the most common are the polar poppy, small sedges, some cereals, and saxifrage.

Northern tundra distributed mainly on the mainland coast. Their important difference from the arctic ones is the presence of a closed vegetation cover. Mosses and lichens cover 90% of the soil surface. Green mosses and bushy lichens predominate; lichen is often found. The species composition of flowering plants is also becoming more diverse. There are saxifrage, ozhiki, viviparous mountaineer. From shrubs - lingonberry, blueberry, wild rosemary, crowberry, as well as dwarf birch (dwarf birch), willow.

V southern tundra, as in the northern ones, the vegetation cover is continuous, but it can already be divided into tiers. The upper tier is formed by dwarf birch and willows. Medium - grasses and shrubs: crowberry, lingonberry, blueberry, wild rosemary, sedge, cloudberry, cotton grass, cereals. Lower - mosses and lichens.

The harsh climatic conditions of the tundra "forced" many plant species to "acquire" special adaptations. So, plants with creeping and creeping shoots and leaves collected in a rosette better "use" the warmer ground air layer. Short stature helps to survive the harsh winter. Although strong winds make the tundra snow cover thin, it is enough to cover and survive.

Some adaptations "serve" plants and in summer time... For example, cranberries, dwarf birch, and crowberry “struggle” to retain moisture by “reducing” the size of the leaves as much as possible, thereby reducing the evaporating surface. In dryad and polar willow, the underside of the leaf is covered with dense pubescence, which impedes the movement of air and thereby reduces evaporation.

Almost all plants in the tundra are perennial. For some species, the so-called viviparity is characteristic, when, instead of fruits and seeds, the plant has bulbs and nodules, which quickly take root, which provides a "gain" in time.

Animals and birds that constantly inhabit the tundra have also adapted well to the harsh natural conditions. They are saved by thick fur or fluffy plumage. In winter, animals are white or light gray in color, and in summer they are grayish brown. This helps to camouflage.

Typical animals of the tundra are arctic fox, lemming, white hare, reindeer, white polar and tundra partridges, snowy owl. In summer, the abundance of food (fish, berries, insects) attracts birds such as waders, ducks, geese, etc. to this natural area.

The tundra has a fairly low population density. The indigenous peoples here are the Sami, Nenets, Yakuts, Chukchi, etc. They are mainly engaged in reindeer herding. The mining of minerals is actively carried out: apatite, nepheline, non-ferrous metal ore, gold, etc.

The railway communication in the tundra is poorly developed; permafrost is an obstacle to the construction of roads.

Forest tundra

Forest tundra- transition zone from tundra to taiga. It is characterized by the alternation of areas occupied by forest and tundra vegetation.

The climate of the forest-tundra is close to that of the tundra. The main difference: the summer here is warmer - the average July temperature is + 11 (+14) ° С - and longer, but the winter is colder: the influence of the winds blowing from the mainland affects.

The trees in this zone are undersized and bent to the ground, have a curved appearance. This is due to the fact that permafrost and waterlogged soil do not allow plants to have deep roots, and strong winds bend them to the ground.

In the forest-tundra of the European part of Russia, spruce prevails, pine is less common. Larch is widespread in the Asian part. Trees grow slowly, their height usually does not exceed 7-8 m. Due to strong winds, the flag-like shape of the crowns is widespread.

The few animals that spend the winter in the forest-tundra are perfectly adapted to the local conditions. Lemmings, voles, tundra partridge make long passages in the snow, feed on leaves and stems of evergreen tundra plants. With an abundance of food, lemmings even bring offspring at this time of the year.

On small forests and bushes along the rivers, animals from the forest zone enter the southern regions: the white hare, Brown bear, ptarmigan. There are wolf, fox, ermine, weasel. Small insectivorous birds fly in.

Subtropics

This zone, which occupies the Black Sea coast of the Caucasus, is characterized by the smallest extent and area in Russia.

The total solar radiation reaches 130 kcal / cm 2 per year. Summer is long, winter is warm (average January temperature is 0 ° С). The sum of active temperatures is 3500-4000 ° C. Under these conditions, many plants can develop all year round... In the foothills and on mountain slopes, 1000 mm or more of atmospheric precipitation falls per year. On flat areas, snow cover is practically not formed.

Fertile red earth and yellow earth soils are widespread.

The subtropical vegetation is rich and varied. Vegetable world represented by evergreen rigid-leaved trees and shrubs, among which we will name boxwood, laurel, cherry laurel. Oak, beech, hornbeam, maple forests are widespread. Thickets of trees intertwine with liana, ivy, wild grapes. There are bamboo, palms, cypress, eucalyptus.

Among the representatives of the animal world, we note the chamois, deer, wild boar, bear, pine and stone marten, Caucasian black grouse.

The abundance of warmth and moisture allows the cultivation of such subtropical crops as tea, tangerines, lemons. Large areas are occupied by vineyards and tobacco plantations.

Favorable climatic conditions, the proximity of the sea and mountains make this area large recreational area our country. There are numerous camp sites, rest houses, sanatoriums.

In the tropical zone there are moist forests, savannahs and woodlands, deserts.

Pretty much plowed up tropical rainforest(South Florida, Central America, Madagascar, Eastern Australia). They are usually used for plantations (see atlas map).

The subequatorial belt is represented by forests and savannas.

Subequatorial moist forests located mainly in the Ganges valley, the southern part Central Africa, on the northern coast of the Gulf of Guinea, northern South America, northern Australia and the islands of Oceania. In drier areas, they are replaced savannah(Southeast Brazil, Central and East africa, central regions of Northern Australia, Hindustan and Indochina). Typical representatives animal world subequatorial belt- ruminant artiodactyls, predators, rodents, termites.

At the equator, an abundance of precipitation and high temperatures led to the presence of a zone here evergreen wet forests (Amazon and Congo basin, on the islands of Southeast Asia). The natural zone of evergreen humid forests holds the world's record for the diversity of animal and plant species.

The same natural areas are found on different continents, however, they have their own characteristics. First of all, we are talking about plants and animals that have adapted to existence in these natural zones.

The natural area of ​​the subtropics is widely represented on the coast Mediterranean Sea, south coast Crimea, in the southeastern United States and in other regions of the Earth.

Western Hindustan, Eastern Australia, the Parana Basin in South America and South Africa- zones of distribution of more arid tropical savannas and woodlands. The most extensive natural area tropical belt -desert(Sahara, the Arabian Desert, the deserts of Central Australia, California, as well as the Kalahari, Namib, Atacama). Huge spaces of pebble, sandy, rocky and saline surfaces are devoid of vegetation. The fauna is small n.

Natural complex- a territory that has a certain unity of nature, due to the commonality of its origin and history of development, the originality of its geographical position, and modern processes operating within its boundaries. In a natural complex, all components are linked to each other. Natural complexes are varied in size. The largest natural complex (PC) is a geographic envelope. Continents and oceans, natural zones are also PCs. A small ravine or lake is also a natural complex. The formation of natural complexes has been going on for a long time.

Geographic belt- the largest territorial unit of the latitudinal-zonal division of the geographic envelope, characterized by a common thermal conditions. The latitudinal location of the geographic zones is mainly determined by the change in the amount of solar radiation from the equator to the poles of the Earth. Humidity can be different within geographic zones, which makes it possible to distinguish geographic zones and subzones within each zone.

Natural areas- natural complexes occupying large areas characterized by the dominance of one zonal type of landscape. Formed mainly under the influence of climate - the features of the distribution of heat and moisture, their ratio. Each natural zone has its own type of soil, flora and fauna.

The appearance of the natural zone is determined by the type of vegetation cover. But the nature of the vegetation depends on climatic conditions - thermal regime, moisture, illumination.

As a rule, natural zones stretch in the form of wide stripes from west to east. There are no clear boundaries between them, the zones gradually pass into one another. The latitudinal location of natural zones is disturbed by the uneven distribution of land and ocean, relief, remoteness from the ocean. For example, in temperate latitudes Natural zones in North America are located in the meridional direction, which is associated with the influence of the Cordilleras, which impede the passage of moist winds from The Pacific inland. There are almost all zones in Eurasia Northern hemisphere, but their width is not the same. For example, zone mixed forests gradually narrows from west to east with distance from the ocean and an increase in the continentality of the climate. In the mountains, natural zones change with height - altitudinal zonation. Altitudinal zonation is due to climate change with upward movement. The set of altitudinal zones in the mountains depends on the geographical position of the mountains themselves, which determines the nature of the lower belt, and the height of the mountains, which determines the nature of the highest altitude belt for these mountains. The higher the mountains and the closer they are to the equator, the more altitude zones they have.

The location of the altitudinal zones is also influenced by the direction of the ridges relative to the sides of the horizon and prevailing winds... So, the southern and northern slopes of the mountains may differ in the number of altitudinal zones. As a rule, there are more of them on the southern slopes than on the northern ones. On slopes exposed to humid winds, the vegetation will differ from that of the opposite slope.

The sequence of changes in altitude zones in the mountains practically coincides with the sequence of changes in natural zones on the plains. But in the mountains, the belts change faster. There are natural complexes typical only for mountains, for example, subalpine and alpine meadows.

Natural land areas.

Evergreen tropical and equatorial forests are located in the equatorial and tropical zones of South America, Africa and the islands of Eurasia. The climate is humid and hot. The air temperature is constantly high. Red-yellow ferralite soils are formed, rich in iron and aluminum oxides, but poor in nutrients. Dense evergreen forests - a source a large number plant litter. But organic matter entering the soil does not have time to accumulate. They are absorbed by numerous plants, washed out by daily precipitation into the lower soil horizons. The equatorial forests are multi-tiered. The vegetation is represented mainly by arboreal forms that form multi-tiered communities. Characterized by a high species diversity, the presence of epiphytes (ferns, orchids), lianas. Plants have tough, leathery leaves with devices that get rid of excess moisture (droppers). The fauna is represented by a huge variety of forms - consumers of decaying wood and leaf litter, as well as species that live in tree crowns.

Savannah and woodlands - natural zones with characteristic herbaceous vegetation (mainly cereal) in combination with individual trees or their groups and shrub thickets. They are located north and south of the equatorial forest zones of the southern continents in the tropical zones. The climate is characterized by the presence of a more or less prolonged dry period and high air temperatures throughout the year. In savannas, red ferralite or red-brown soils are formed, which are richer in humus than in equatorial forests. Although nutrients are washed out of the soil during the wet season, humus builds up during the dry season. Herbaceous vegetation with separate groups of trees prevails. Characterized by umbrella crowns, life forms that allow plants to store moisture (bottle-shaped trunks, succulents) and protect themselves from overheating (draining and waxy coating on the leaves, the arrangement of leaves with an edge to the sun's rays). The animal world is characterized by an abundance of herbivores, mainly ungulates, large predators, animals processing plant litter (termites). With distance from the equator in the Northern and Southern Hemispheres, the duration of the dry season in the savannas increases, the vegetation becomes more and more sparse.

Deserts and semi-deserts are located in tropical, subtropical and temperate climatic zones. The desert climate is characterized by an extremely low amount of precipitation throughout the year. The daily amplitudes of air temperature are large. In terms of temperature, they are quite different: from hot tropical deserts to deserts of the temperate climatic zone. All deserts are characterized by the development of desert soils, poor in organic matter, but rich in mineral salts. Irrigation allows them to be used for agriculture.

Soil salinization is widespread. The vegetation is sparse and has specific adaptations to the arid climate: the leaves are turned into thorns, root system greatly surpasses the aerial part, many plants are able to grow on saline soils, bringing salt to the surface of the leaves in the form of plaque. The variety of succulents is great. Vegetation is adapted to either "trapping" moisture from the air, or to reduce evaporation, or both. The animal world is represented by forms capable of for a long time do without water (store water in the form of fatty deposits), travel long distances, experience the heat, go into holes or hibernate. Many animals are nocturnal.

Stiff-leaved evergreen forests and shrubs are located in subtropical zones in conditions Mediterranean climate with dry hot summers and humid, mild winters. Brown and red-brown soils are formed.

The vegetation cover is represented by coniferous and evergreen forms with leathery leaves covered with a waxy bloom, pubescence, usually with a high content of essential oils. This is how the plants adapt to dry hot summers. The animal world has been greatly exterminated; but herbivorous and deciduous forms are characteristic, there are many reptiles, birds of prey.

Steppe and forest-steppe - natural complexes characteristic of temperate zones. Here, in a climate with cold, often snowy winters and warm, dry summers, the most fertile soils are formed - chernozems. Herbaceous vegetation predominates, in typical steppes, prairies and pampas - cereal, in dry varieties - wormwood. Almost everywhere, natural vegetation has been replaced by agricultural crops. The fauna is represented by herbivorous forms, among which ungulates are strongly exterminated, mainly rodents and reptiles, which are characterized by a long period of winter dormancy, and birds of prey have survived.

Broad-leaved and mixed forests grow in temperate zones in climates with sufficient moisture and a period with low, sometimes negative temperatures... The soils are fertile, brown forest (under broadleaf forests) and gray forest (under mixed forests). Forests are usually formed by 2-3 species of trees with a shrub layer and a well-developed herbaceous cover. The fauna is diverse, clearly divided into tiers, represented by forest ungulates, predators, rodents, insectivorous birds.

Taiga is widespread in the temperate latitudes of the Northern Hemisphere in a wide strip in climates with short warm summers, long and severe winters, sufficient precipitation and normal, in some places excessive moisture. In the taiga zone, under conditions of abundant moisture and a relatively cool summer, intensive washing of the soil layer and humus takes place; little is formed. Under its thin layer, due to soil leaching, a whitish layer is formed, which, outward appearance looks like ash. Therefore, such soils are called podzolic. Vegetation is represented by various types coniferous forests in combination with small-leaved.

Well developed tiered structure, which is also characteristic of the animal world.

Tundra and forest-tundra are common in subpolar and polar climatic zones. The climate is harsh with short and cold growing seasons and long and severe winters. With a small amount of precipitation, excessive moisture develops. Soils - peat-gley, under them a layer permafrost... The vegetation cover is represented mainly by herb-lichen communities, with shrubs and dwarf trees. The fauna is peculiar: ordinary large ungulates and predators, nomadic and migratory forms are widely represented, especially migratory chicks, which spend only the nesting period in the tundra, there are practically no burrowing animals, few grain-eaters.

Polar deserts are common on islands in high latitudes. The climate of these places is extremely harsh; winter and polar night dominate most of the year. Vegetation is scarce, represented by communities of mosses and crustaceans. The fauna is associated with the ocean, there is no permanent population on land.

Areas of altitudinal zonation are located in a wide variety of climatic zones and are characterized by a corresponding set of altitudinal zones.

Their number depends on latitude (in equatorial and tropical regions it is more) and on the height of the mountain range, the higher, the greater the set of belts.

In accordance with the change in climatic conditions from north to south, they replace each other in latitude and natural areas(fig. 55). In addition, depending on changes in climatic conditions, with distance from the oceans, natural zones are replaced in the meridional direction. Differences in climatic conditions vegetation, fauna and soil cover react sensitively.

Within the natural zone, azonal natural complexes can be found, for example, oases in deserts, galley forests along river valleys in arid regions.

The natural areas shown on the map (Fig. 55) are actually very much changed by human activity.

Natural zones change from the equator to the poles and from the coasts of the oceans to the interior of the continents along with changing climatic conditions.

Latitudinal change of natural zones

On the globe, temperatures are mostly natural increase from high latitudes (poles) to low (equator). The belts of high and low atmospheric pressure (predetermining the humidity of the climate) alternate . It turns out "striped" (from the poles to the equator): cold and dry - moderate temperatures and humid - hot and dry - hot and humid. Therefore, the "device" of one or another natural zone is ultimately due to the superposition of thermal belts and belts of atmospheric pressure.

Rice. 55. Map of natural areas

Meridional change of natural zones

Distance from oceans and features general circulation atmosphere - the main reasons for the meridional change of natural zones.

The map of natural zones (Fig. 55) shows that in Eurasia, where the land reaches its maximum size, the meridional change in natural zones is especially well traced.

In the temperate zone, the western transport brings moisture relatively evenly to the western coasts. On the eastern shores there is a monsoon circulation (rainy and dry seasons). When moving inland, the forests of the western coast are replaced by steppes, semi-deserts and deserts. As we approach the east coast, forests reappear, but of a different type.

Compare the natural zones of the tropical belt in Africa, Australia and South America. In the tropics - trade wind circulation, moisture comes from the east. Therefore, the humid tropical forests of the eastern coasts, when moving westward, inland, are replaced by savannas and woodlands. There are deserts on the western coasts. Most of the equatorial latitudes are occupied by constantly humid forests, and on the eastern coasts the forests are variable-humid.

The ratio of heat and moisture at one latitude is different on the western coasts, in the interior regions and on the eastern coasts of the continents. Material from the site

Figure 56 shows that on the western coast of Eurasia in the region of 40 ° N. sh. there is a zone of hard-leaved evergreen forests and shrubs of the Mediterranean type (Fig. 56, A). On the east coast the mainland at the same latitude is a zone of mixed forests, and the forests there are of coniferous-broad-leaved monsoon type (Fig. 56, B). On the line of the Northern Tropic on the west coast of Africa there are deserts, and on the east coast of Eurasia there are variable humid monsoon forests.

Altitudinal zonality

The latitudinal and meridional change of natural zones is disturbed by the features of the relief. In those places where mountains rise, the natural zone of the surrounding plain is at the foot. Above, the change in natural conditions occurs in accordance with the altitudinal zonality. The closer to the equator and the higher the mountains, the greater the number of altitudinal zones.

Questions about this material:

Natural zone - the territory of the earth's surface, is characterized by a commonality not only of temperature conditions, but also of moisture, which leads to the commonality of biological components of landscapes (vegetation, soils, etc.). On the plains, natural zones run mainly in the latitudinal (west-east) direction and overshadow each other in the meridional direction, depending on the wave geographic zoning... Altitude zoning is observed in the mountains.

In the arctic deserts, due to the harsh climate with low temperatures, physical weathering processes prevail. The biological cycle under such conditions is slow, organic residues decompose slowly. The soils of the arctic deserts are formed there. There are polar bears and arctic foxes. Polar birds settle on the rocks.

An important feature of the tundra is treelessness. The main vegetation background is mosses and lichens. Perennial and evergreen dwarf shrubs and dwarf grasses are very common. Tundra gley soils prevail. In some areas, due to the close occurrence groundwater or due to the difficult drainage in the depressions of the relief, swamps with a large thickness of peat are formed.

In the tundra and forest-tundra, specialization is reindeer husbandry. It is combined with hunting and fishing. The conditions here are almost unsuitable for crop production.

Podzolic soils are formed in the taiga. Permafrost-taiga is widespread, and in the relief depressions and with insufficient drainage - boggy soils and deep peat bogs.

In the taiga, plant growing is developed in islands, in river valleys. Livestock raising is of great importance. In the southern part of the taiga and in mixed forests (mainly sod-podzolic soils) the cultivation of dairy cattle is associated with the sowing of flax, sown grasses and forage crops. Potatoes are grown in the mixed forest zone. Pig breeding is based on milk and potato processing waste. In the sown area, grain crops are in the lead. There are few forage crops here, so dairy farming develops on natural pastures and hayfields.

In the forest-steppe in the north of the black earth belt, wheat, rye, and oats are grown. All industrial crops are potatoes and hemp. Potatoes are common mainly on sandy loam soils, hemp - on loamy soils.

The forest-steppe has high plowing; the area of ​​pastures is small, therefore, fodder root crops, legumes, and potatoes are grown in a crop rotation with grain crops. Many fodder waste comes from the technical processing of potatoes and grain. It is a base for breeding cattle, pigs and poultry. In the forest-steppe they cultivate sugar beet and in crop rotation with them, winter wheat, corn. An important industry is gardening.

In the steppes, chernozems and black earth-like, as well as chestnut soils are formed. The area is dominated by wheat and corn crops. Corn is a fodder for meat and dairy cattle breeding and for poultry. Of the industrial crops, sunflower is distinguished.

In deserts and semi-deserts, brown and gray-brown desert soils are widespread. Meat and wool sheep breeding and karakul breeding are developing there. The valleys of large rivers are used for irrigated crop production. Natural conditions favorable here for cotton growing. Grain crop on watering - rice. In the oases - sericulture, viticulture, horticulture and melon growing.

In the humid subtropics, thermophilic crops are grown - tea, citrus fruits, yellow tobacco, essential oil.

So, in each natural zone there is a specialization in certain types plant growing and animal husbandry.

Seas

The sea is a part of the ocean, more or less separated by land or elevations of the underwater relief and is characterized by a certain hydrological regime. By the level of isolation and characteristics hydrological regime seas are subdivided into three groups: internal (middle and closed), marginal and inter-island. The median seas are sometimes divided into inland and intercontinental.

Marine plants, especially animals, have a large economic value- they are used for the manufacture of food products, feed for livestock, fertilizers, technical raw materials. Mining marine plants(seaweed, red algae, etc.), fishing, hunting in many coastal countries is the main source of livelihood for the inhabitants. Significant amount people are busy with pearl mining.

Hunting for whales, seals, walruses is of great importance in the economy.

The prey of invertebrates of marine animals is also widespread: molluscs, crustaceans, echinoderms, sponges, worms, corals.

Algae especially great importance have Fukushima, Sargasso and kelp (seaweed, etc.). they are used as food products, livestock feed, for the production of fertilizers, as raw materials for industry.

The seas have long been used by waterways. With the improvement of technology, rowing ships gave way to sailing ships, sailing ships - steam, diesel and, finally, nuclear. The conditions of navigation are improving, the distance of transportation is increasing. Now by sea in different directions the entire globe is encircled. With the construction of large canals - Suez (1869 p.), Kiel (1895 p.), Panama (1914), the sea routes were significantly reduced and the direction of cargo flows changed.

Despite the fact that the construction of ports, canals, ships, ferries requires significant investment, sea transport is the cheapest. Its rational use becomes a means of communicating to countries, reducing production costs.

With the development of maritime transport in coastal areas, a kind of port economy (ocean cycle) is created, which includes: the water part (water area) - water approaches, roadsteads, inland basins for anchorage of ships and the coastal part (territory) - land approaches ( railways, roads, urban transport), warehouses, hydraulic structures(breakwaters, breakwaters), mooring facilities (piers, embankments, etc.), loading and unloading facilities, etc. In port cities, industries are developing that serve shipping, process imported raw materials. According to specializes Agriculture adjacent areas.

On the basis of the seas, zones are formed economic cooperation... So, on the basis of the Black Sea, the Black Sea region of economic cooperation (cres) is developing. In 1990-1992 pp. intergovernmental meetings were held at which sub-regional economic integration was created - Parliamentary Assembly the Black Sea states. Representatives of Ukraine, Russia, Greece, Turkey, Albania, Romania, Bulgaria, Azerbaijan, Georgia, Moldova and Armenia take part in the work of this organization. The main task of the Black Sea integration is to create a regime for the free promotion of goods, services and capital in order to expand production cooperation and joint entrepreneurship.

Main questions. What is a natural area? In natural zones of what latitudes are the territories of the southern continents mainly located?

Natural area(fromGreek zone - belt)- a large territory with a common temperature and moisture conditions, soils, vegetation and fauna. Natural zones are closely related to climatic zones. The name of the natural zones is given according to the main distinguishing feature - vegetation (forest zone, zone of steppes, deserts). In the World Ocean, natural zones differ in water masses, organic matter, etc.

Natural areas on land and in the ocean gradually merge into one another. They naturally replace each other mainly in the latitudinal direction and less often in the meridional direction. Change of natural zones is a typical manifestation the law of geographic zoning... We will get acquainted with natural areas as we move from the equator to the poles. (Examine the location of natural areas on the Natural Areas map).

Natural zones of equatorial and subequatorial latitudes. The zone of humid equatorial forests occupies about 6% of the land, located in the belt equatorial climate with high temperatures and high rainfall throughout the year (rice). ( Determine on the map on which continents this zone is located.) She holds the first place among the forest zones of the earth in terms of the diversity of plants and animals. Evergreen equatorial forests are dense, impassable, grow on red-yellow ferralite (from lat... ferrum - iron, aluminum - aluminum and greek... lithos - stone) soils. The forests are distinguished by an abundance of palms, lianas and epiphytes (plants that live on other plants). Mangroves (evergreen shrubs) are widespread along the sea coasts. There are hundreds of species of trees in such a forest, and they are arranged in several tiers. Many of them bloom and bear fruit all year round. The fauna is also diverse. Most of the inhabitants live in trees. They have tenacious legs and tail: sloth, anteater, monkeys, howler monkeys, flying foxes. The largest animal that lives in the crowns of trees is the gorilla ape. Terrestrial animals are characterized by tapirs, hippos, jaguars, leopards. There are many beautiful butterflies and insects in the forests.

Savannah zone and woodlands located in subequatorial belt Africa, Australia, South America. The peculiarity of the climate is the alternation of wet and dry seasons. Due to insufficient moisture, the vegetation cover is an endless sea of ​​grasses. Separately, there are low trees and bushes. The soils are of a peculiar color: red and red-brown. The reason for this is the accumulating iron compounds. The animal world is diverse. The richness of herbs contributes to the spread of large herbivorous and carnivorous mammals, birds, reptiles, insects. ( Describe the flora and fauna from the illustrations).

Natural zones of tropical and subtropical latitudes. Tropical deserts- the most extensive natural zone of the tropical climatic zone. It is most pronounced on the western outskirts of the continents, which are washed by cold currents. (Rice) ( Identify the largest deserts in the tropics using maps.) The greatest deserts are located in Africa: Sahara, Kalahari, Namib. The climate is tropical desert, hot and dry, because the soils are underdeveloped, often saline. The vegetation is sparse, sparse (stiff-leaved grasses and shrubs). The fauna is represented mainly by reptiles (snakes, lizards) and insects. Among mammals - ungulates (gazelle antelope, etc.), capable of covering long distances in search of water. Deserts are varied: sandy, clayey and stony... Oases are located near the water sources. They grow date palms, oleanders.

In the tropical zone, there is also wet zone and variable rainforest ... It formed in the eastern part of South America, in the northern and northeastern parts of Australia, on about. Madagascar. The climate is humid with consistently high temperatures and a lot of precipitation in summer. Variably moist, evergreen forests, rich in species composition (palms, ficuses), grow on red-yellow and red soils. They are like equatorial forests. The fauna is rich and varied.

Subtropical hard-leaved evergreen forests and shrubs typical for the western part of the continents, where the climate Mediterranean: hot and dry summer, warm and rainy winter. (rice) ( Determine the location of the natural area) The brown soils are highly fertile and are used for the cultivation of valuable subtropical crops. The lack of moisture during the period of intense solar radiation led to the appearance of adaptations in plants in the form of hard leaves with a waxy coating, which reduce evaporation. Stiff-leaved evergreen forests are decorated with laurels, wild olives, cypresses, yews. In large areas, they have been cut down, and their place is taken by fields of grain crops, orchards and vineyards. Wild boar, bear, deer, roe deer are found in the forests. Alternately - wet (including monsoon) forests located in the east of the continents, where the climate is subtropical monsoon. Precipitation occurs in summer. The forests are dense, evergreen, broad-leaved and mixed; they grow on red and yellow soils. The fauna is ubiquitous.

Zones of subtropical steppes, semi-deserts and deserts distributed by sectors in the interior regions of the continents. The subtropical dry climate with hot summers and relatively warm winters allows drought-resistant grasses and grasses (wormwood, feather grass) to grow on gray-brown steppe and brown desert soils. The fauna is distinguished by its species diversity. Typical mammals are gophers, jerboas, gazelles, kulans, jackals and hyenas. Lizards and snakes are numerous.

Most of the continents of South America, Africa, southern Asia are located in natural zones of equatorial and tropical latitudes.

1. Highlight the essential features of the concept of "natural zone". 2. Show natural areas on a physical map of the world. Determine in which natural zones are located mainly the continents of the southern, and in which - the northern hemisphere? * 3. Study the distribution climatic zones and natural zones when driving along 20º E north and south of the equator. Fill in the table "Natural zones and climatic zones". ** 4. Make a conclusion about the living conditions of the population in various natural zones (to choose from).