Signs by which natural areas are characterized. Natural areas. Natural land areas

Development What is a natural area? Natural area — physical-geographical zone — is part geographic envelope Earth and geographical zone, has its characteristic components natural ingredients and processes. What are there?

1. natural areas
2. Arctic (Antarctic) desert.
3. Forest-tundra and tundra. Taiga, mixed, wide, deciduous forests.
4. rainforests
5. Forest-steppe and steppe.
6. Deserts and semi-deserts.

Savannah. Arctic and ant — arctic deserts Such deserts occupy about 5 million square kilometers (the largest places are Greenland, Antarctica, the northern parts of Eurasia and North America), mainly consisting of small rocks or scree, as well as glaciers. Feature there is a lack of polar desert sunlight

over a long period of time, approximately 10 months. Most of the soil is covered by permanent permafrost. The average temperature that occurs in these zones is up to -30 degrees Celsius, in winter -60 degrees, in warm seasons, the maximum temperature is +3 degrees. Such deserts are practically devoid of vegetation. Animals in the Arctic include polar bears, walruses, seals, arctic foxes, and seals. In Alaska, Canada and Russia, the Arctic deserts are already gradually turning into tundra. Forest-tundra and tundra - The largest areas of tundra and forest-tundra are located in the north of North America and also Eurasia (mainly Russia and Canada), mainly, such areas are located in the subarctic climate zone. In the southern hemisphere of our planet, tundra and forest-tundra are practically absent. The vegetation is very low, the most common being mosses and lichens. The tundra has a large number of trees such as Siberian larch , dwarf birch, polar willow. Among the animals: deer, wolves, a large number of hares, arctic foxes. average temperature

in warm seasons, it is +5 +10 degrees, in winter the average temperature is -30 degrees. In the Tundra, winter can last up to 9 months. In the forest-tundra the average temperature is +10 +15 degrees. In winter from -10 to -45 degrees. In the tundra and forest-tundra there are a very large number of lakes, due to high humidity, as well as a large number of swamps. Taiga, mixed, broadleaf forests, rainforests - These zones have a characteristic mild climate and. Formed in temperate zones with average rainfall. Usually located in the temperate zone of Russia, Canada, and Scandinavia. Characterized by cold winters and fairly warm summers. Vegetation includes a large number of coniferous trees: pine, fir, larch, spruce. The taiga became famous for its dark coniferous boreal forests. There are also a large number of deciduous trees: birch, poplar, aspen. The main seasons in the taiga and deciduous tropical forests are winter and summer. Autumn and spring are so short that you won't even notice they exist. In the taiga it is either very cold or very hot. It happens that the temperature exceeds +30 degrees Celsius, mostly warm and rainy. In winter there are frosts and up to -50 degrees. There are a very large number of wild animals: brown bear, wolf, fox, wolverine, ermine, sable; there are also deer, elk, and roe deer. But usually, they live in areas where there are a very large number of deciduous trees.

Forest-steppe and steppe - these are areas of the earth that do not have forests, occupy quite vast territories in Eurasia, North America and in the subtropical zones South America. Very low rainfall. The forest-steppe zone passes in the north between the steppes and forests in the north, namely, from the steppes, a transition to semi-deserts is formed and then deserts begin. In the forest-steppes it is just the opposite, there is quite a lot humid climate(up to 600 mm) than in the steppe, so an element such as meadow steppe is formed here. The temperature in the steppes, as well as in forest-steppes, ranges from -16 to +10 degrees in winter, +15 +30 degrees in summer. Vegetation usually changes from north to south, grasses are replaced by feather grass, and it is replaced by wormwood. Among the animals there are gophers, marmots, bustards, and steppe eagles. There are also hedgehogs, squirrels, foxes, hares, snakes, moose, storks, and beavers.

Deserts and semi-deserts - this is one of the most large areas, it occupies one fifth of earth's surface. It is clear that the largest part of these zones is located in the tropics (deserts and semi-deserts): Africa, Australia, the tropics of South America, as well as the Arabian Peninsula in Eurasia. The driest desert is the Atacama, which is located in Chile; there is practically no rain there. In the most big desert The land is Sahara, there is also very little precipitation, in summer the temperature can reach +50; for deserts this is a very common occurrence. There are frosts in winter. In deserts there is practically no flora, this is explained by low humidity and a very dry climate; there are very few plants that can survive in such a climate. There are plenty of animals: jerboas, gophers, snakes, lizards, scorpions, camels.

Savannah - Such zones occur, for the most part, in the subequatorial belt of the Earth. The climate here is varied, sometimes very dry, and sometimes quite rainy. The average temperature for the year ranges from +15 to +25 degrees. Largest quantity shroud, located in South America, Africa, Indochina, the Hindustan Peninsula, and the northern regions of Australia. Very diverse fauna, mainly herbaceous vegetation, various trees and shrubs. Among the animals that live in shrouds, the following can be distinguished: elephants, cheetahs, lions, rhinoceroses, leopards, zebras, giraffes, antelopes. A large number of birds and insects.

If a hundred artists living in different countries, offered to draw a portrait of the Earth, then we would get completely different portraits. On one we would see the harsh tundra, on the other - a lush jungle, on the third - a desert languishing in the heat... And if all the portraits were collected in one exhibition, we would be surprised: how many faces our planet has!

These different faces appeared on the Earth because the conditions for the life of organisms on it are very diverse and completely different natural zones have developed in different parts of the planet.

Among the natural zones of the Earth, several main ones can be distinguished, those that occupy most of its surface. Their distribution on the planet depends on climate, mainly on the distribution of heat and moisture.

IN northern regions Eurasia and North America and on many adjacent islands are located tundra. There is very little heat here, the soil is frozen by permafrost. The natural community of the tundra consists of lichens, mosses, dwarf trees, rodents lemmings, ptarmigan and White Owl, reindeer, arctic fox.

To the south of the tundra, where there are still very cold winters, there is taiga. The basis of the natural community of the taiga is undemanding to heat coniferous trees. Larch, cedar pine, spruce, and fir form taiga forests that occupy vast spaces. The taiga is inhabited by capercaillie, nutcracker, flying squirrel, and sable.

South of the taiga, where there is more heat and no heat at all permafrost, grow thermophilic deciduous trees- oak, maple, linden. Together with other trees, various shrubs, herbs, mushrooms and, of course, animals, they form mixed And broadleaf forests.

In areas where there is a lot of heat, but there is not enough moisture for the existence of forests, there are grassy plains- steppes and savannas. They are found on all continents except Antarctica. The steppes are especially extensive in Eurasia, and savannas in Africa. The basis of the community of grassy plains is, naturally, grasses, although separately growing trees are also found in savannas. A variety of insects and large animals feed on grasses: in the African savannah, for example, antelopes and zebras. These animals are hunted by predators. The most famous predator African savannah- a lion.

The driest areas of the Earth are occupied by desert. They are also found on all continents except Antarctica. Few organisms have adapted to life here, and yet the desert community is not so poor. In the deserts Central Asia, for example, saxaul, sand sedge, camel thorn grow, insects live (darkling beetles, grasshoppers); reptiles (round-headed lizard, monitor lizard, sand boa, cobra); mammals (goitered gazelle, jerboas, gerbils).

On the map you see two lines encircling Earth, - Northern Tropic and Southern Tropic. Between them, on both sides of the equator, is located tropical rainforest. Here all year round It is very warm and there is heavy rainfall. These conditions are especially favorable for plants and animals. Therefore, the tropical rainforest is the richest in species natural community Earth.

Test your knowledge

1. List the main natural zones of the Earth.
2. What determines the distribution of natural zones on Earth?
3. Give a brief description of the tundra.
4. What trees form the basis of the taiga, mixed and deciduous forests?
5. What do all the grassy plains on our planet have in common?
6. Give a brief description of the desert.
7. Why is the tropical rainforest the most species-rich natural community?

Think!

1. Using examples, prove that the distribution of natural zones on Earth depends on the distribution of heat and moisture.
2. The characteristic features of which natural areas are listed below?
   1. Largest variety of species;
   2. predominance herbaceous plants;
   3. an abundance of mosses, lichens and dwarf trees;
   4. a bunch of coniferous plants few species.
3. Name these organisms. What natural areas do they live in?

The main natural zones of the Earth are tundra, taiga, mixed and deciduous forests, grassy plains, deserts, and tropical rainforests. Their distribution on Earth depends on climate.

1. What is unique about the location of natural areas on the mainland?
In the north of the continent, according to the law of latitudinal zonation, natural zones change in the direction from north to south, and in the central region - from east to west. The reason for this is that, due to the peculiarities of the relief, the ratio of heat and moisture on the continent changes noticeably not only in the latitudinal direction, but also in the meridional direction.

2. Find in the text definitions of the concepts “tundra”, “taiga”, “steppe”, name their essential features.
Tundra is the name given to treeless spaces of the subarctic zone, covered with moss-lichen and shrub vegetation on poor tundra-marsh soils.
Taiga is a temperate zone, the vegetation of which is dominated by coniferous trees with an admixture of small-leaved species on podzolic soils.
Steppes are treeless spaces of temperate and sub tropical zones, covered with herbaceous vegetation on chernozem and chestnut soils.
The main features of natural areas are climatic conditions formations, soils, flora and fauna.

3. Name the representatives of the animal world of each natural zone. Use the text and the atlas map to answer.

4. Find on the atlas map National parks and nature reserves in North America. In what natural areas are they located?

A natural zone is a part of the earth's surface with the same type of relief, soil, flora and fauna. The main forming factor of a natural zone is climate. Eight natural complexes have formed on the territory of Russia. They replace each other from north to south. The largest territory is occupied by the taiga zone, and the smallest by semi-deserts and deserts. Below is a distribution map and geographical description all natural zones in Russia, as well as a table with brief description each natural area.

Read also:

Map of Natural Areas of Russia

Arctic desert

The upper boundary of the region runs along the Franz Josef Land archipelago, the lower boundary - on Wrangel Island. The main feature is the presence of ice and snow throughout the year. The average temperature in winter is about -50º C. During this period, a lot of snow falls and strong winds blow. The polar night lasts 4 months. Summer temperatures average +4º C. August is considered the warmest month of the year.

There are no lakes or swamps. The flora is represented mainly by lichens. Here you can count several endemics: arctic willow, cotton grass, forget-me-not and chickweed. few due to sparse flora. In the cold desert, polar bears, arctic foxes, reindeer and lemmings. The rocky coasts are favored by eiders, guillemots and other birds. The shores of some islands are complete bird colonies.

Tundra

The natural complex stretches from the Kola Peninsula to Chukotka. Its area is an eighth of the entire area of ​​Russia. characterized by plains, only mountains and hills appear near the Urals. This region is characterized by harsh winter with average temperatures of about -32º C and a duration of more than six months. During the winter season, strong winds blow, which remove layers of snow from the soil. Because of this, the soil freezes and becomes waterlogged during the thaw. The polar night lasts from December to February.

The sun has not set since mid-summer. It does not rise high above the horizon, therefore, most of the rays are scattered in the atmosphere. The so-called polar day is coming. Average summer temperatures in the tundra do not exceed +5º C. Among the vegetation, lichens of all kinds and mosses are especially widespread. Perennial crops are represented by saxifrage, lingonberry, wild rosemary, cassandra and cloudberry. are a food source for reindeer and hares. In addition to them, wolves, arctic foxes and partridges. During short summer You can watch loons, waders and geese.

Forest-tundra

The region stretches from the tundra to the taiga. The climate in this transition zone is much milder than in the neighboring northern one. In January, the thermometer does not rise above -40º C, and cold winds constantly blow. However, there is constant snow cover. Winter lasts up to eight months. The average summer temperature is 15º C. Due to high humidity and relatively low summer temperatures, the soil is very swampy.

Forest-tundra is characterized by forests consisting of deciduous trees, birch and spruce. Another feature of the plant world is meadows. They bloom in late spring medicinal herbs. The marshy area is rich in peat and mosses. In this natural area moss grows, which is a source of food for deer. The world of mammals is more diverse than in the tundra. You can observe wolverines, bears, wolves and arctic foxes. Swamps, lakes and rivers are inhabited waterfowl: ducks, swans and loons. The forest-tundra is home to unique birds: peregrine falcons, Siberian Cranes and geese. Some birds, such as the snowy owl and partridge, live in this natural area all year round without flying anywhere.

Taiga

Stretches from the western borders to the coast Pacific Ocean. The area of ​​the biome is about 15 million km². Most The territories are occupied by forests. For the most part, the area is virtually untouched by humans. Taiga winter is cold, the average temperature is -29° C. The snow cover does not melt for more than three months. Summer temperatures average +18º C. Precipitation comes in the form of heavy rains, which increases the humidity level.

The natural zone is represented by numerous rivers, lakes and other bodies of water. The soil layer consists of humus and a large amount of minerals. and unique. Coniferous and deciduous forests are widely represented in the taiga zone. In addition to them there are wetlands and meadows. Thanks to the stable climate and the absence extreme temperatures Most animals do not change their habitat all year round. Hazel grouse, nutcracker, and capercaillie do not fly away, but constantly nest in the taiga.

The climate turned out to be harsh. A few frogs and lizards go into suspended animation with the onset of persistent frosts. The world is represented by wolverine, lynx, elk, brown bear, and sable. The taiga is full of blood-sucking insects that swarm in huge quantities. Frequently, midges are carriers of infectious diseases.

The territory extends from the East European Plain to the Far East. The biome is characterized by a mild climate. Winter temperature does not exceed -25° C. Numerous anticyclones form over the Far East during this period. Snow evenly covers the entire area natural complex. Summers are mostly mild and humid. The July air warms up to +20º C. The warm period lasts 4 months. At this time the maximum amount of rain falls.

The area of ​​mixed and deciduous forests is known for its water potential. There are long flood rivers and lakes here. There are practically no swamps. The earth is saturated with nitrogen, magnesium, calcium and aluminum. Korean cedar, Manchurian walnut, Amur linden, and larch grow in the forests. A lot of bushes. Mosses and lichens cover the soil only in dark and damp places. The forests are rich in fruit and berry plants and mushrooms. This creates conditions for comfortable living for many species of animals. These forests are most used by humans in their activities. The greatest species diversity is found in lands untouched by humans.

Among the inhabitants, one can distinguish the viper, viviparous lizard, and snake. The forests are home to various birds: hazel grouse, black grouse, crossbill, eagle owl, and owl. The natural area is rich in predators - wolves, stoats, foxes, martens are its permanent inhabitants. IN Lately The number of deer has decreased significantly. The forests remain home to hedgehogs, badgers, nutria, moles, hares and marsh turtles.

Forest-steppe zone

The territory that united the East European Plain, West Siberian Plain And Southern Urals, and is transitional between forests and steppes. Winter in the western part of the natural area is very mild and snowy. Temperatures in the east drop to -20° C and little snow falls. Summer temperatures average +18º C, and there is little rainfall.

It is characterized by a combination of forests and grass cover. In the European part, maple, oak, and linden grow. In the Asian zone, aspen and birch trees predominate. The steppe regions are rich in bluegrass and clover. Almost the entire steppe is used for agriculture. People cultivate corn, rye, and wheat. Animals such as squirrel, marten, gopher, bustard, and elk live here.

The anthropogenic factor has led the forest-steppe zone to desertification; the land and water bodies are polluted with toxic substances and nitrates. Unstable vegetable world cannot recover from human activity. The natural forest-steppe complex is gradually disappearing in Russia.

Steppe zone

The natural area is located on the East European Plain and in Western Siberia. In winter, the eastern part of the zone is colder than the west. In summer, the average temperature is +20° C. Maximum amount precipitation occurs in June. There is an alternation of wet and dry seasons. The soil is chernozem, well suited for growing cereals. Some areas are undergoing erosion.

The steppe is dominated by herbaceous vegetation: clover, bluegrass, and wild oats. Sometimes there are shrubs in the area: broom, spirea, wolfberry and blackthorn. All plants are excellent food sources for animals. In the steppes there are a large number of voles, marmots and pikas. The world is represented by ferrets, foxes and wolves. This natural complex is home to birds of prey: owls, hawks, harriers and buzzards.

Semi-deserts and deserts

The territory stretches from Caspian lowland to the borders with Kazakhstan. In winter, the thermometer drops to -16º C, and gusty winds blow. There is practically no snow, so the soil freezes deeply. The maximum amount of precipitation occurs during the short spring period. The average temperature in summer is +25° C. The lands are saline, there is a lot of sand and salt marshes.

The flora is not diverse. Only here you can see remaria, malcomia, acacia, camel thorn, cacti and some cereals. During drought, some plants wither, preserving underground organs. The most recognizable desert tree is saxaul. There are practically no leaves on it, which significantly reduces moisture evaporation. Of the herbaceous plants, black wormwood is famous, which covers the ground, protecting it from drought.

Desert Dwellers Lead. Ground squirrels, jerboas and gerbils may hibernate when the weather gets hot. The amphibian world is represented by geckos, boas and monitor lizards. Predators include corsairs, wolves and foxes. Saiga antelope and camel are considered large. Birds include lark, sajja and lapwing.

Table of natural zones of Russia

Natural area - a territory with similar conditions of temperature and moisture, which determine generally homogeneous soils, vegetation and fauna. On the plains, the zones extend in the latitudinal direction, naturally replacing each other from the poles to the equator. Often, significant distortions in the pattern of the zone are introduced by the relief and the relationship between land and sea.

Arctic and Antarctic deserts . These are cold deserts with very low air temperatures in the Arctic and Antarctica. In this area, snow and ice persist almost all year round. In the warmest month - August - in the Arctic the air temperature is close to 0°C. Ice-free areas are bound by permafrost. Very intense frost weathering. There is little precipitation - from 100 to 400 mm per year in the form of snow. In this zone, the polar night lasts up to 150 days. Summer is short and cold. Only 20 days, rarely 50 days a year, the air temperature exceeds 0°C. The soils are thin, underdeveloped, rocky, and there are widespread scatterings of coarsely broken material. Less than half of the Arctic and Antarctic deserts are covered with sparse vegetation. It is devoid of trees and bushes. Crucible lichens, mosses, various algae, and only some flowering plants are common here. Animal world richer than vegetable. These are polar bears, arctic foxes, polar owls, deer, seals, and walruses. Among the birds, there are penguins, eiders and many other birds that nest on rocky shores and form “bird colonies” in the summer. In the ice desert zone, marine animals are hunted; among birds, eiders are of particular interest, with their nests lined with down. Eider down is collected from abandoned nests to produce clothing worn by polar sailors and pilots. In the icy desert of Antarctica there are Antarctic oases. These are areas of the continental coastal strip free from ice cover, with an area of ​​​​several tens to hundreds of square meters. kilometers. The organic world of oases is very poor; there are lakes.

Tundra. This is an area that lies within parts of the Arctic and subarctic zones in the Northern Hemisphere; in the Southern Hemisphere, the tundra is distributed only on some islands. This is an area with a predominance of moss-lichen vegetation, as well as low-growing perennial grasses, shrubs and low bushes. The trunks of shrubs and the roots of grasses are hidden in the moss and lichen turf.

The climate of the tundra is harsh, the average July temperature only in the south of the natural zone does not exceed +11°C, snow cover lasts 7-9 months. Precipitation amounts to 200-400 mm, and in some places up to 750 mm. main reason treeless tundra - low temperatures air in combination with high relative humidity, strong winds, widespread permafrost. The tundra also creates unfavorable conditions for the germination of seeds of woody plants on the moss-lichen cover. Plants in the tundra are pressed to the surface of the soil, forming densely intertwined shoots in the form of a pillow. In July, the tundra is covered with a carpet of flowering plants. Due to excess moisture and permafrost, there are many swamps in the tundra. On the warmed banks of rivers and lakes you can find poppies, dandelions, polar forget-me-nots, and pink mynacle flowers. Based on the predominant vegetation in the tundra, 3 zones are distinguished: arctic tundra , characterized by sparse vegetation due to the severity of the climate (in July +6°C); moss-lichen tundra , characterized by richer vegetation (in addition to mosses and lichens, sedge, bluegrass, and creeping willow are found here), and shrub tundra , located in the south of the tundra zone and characterized by richer vegetation, which consists of thickets of willow and alder bushes, which in some places rise to the height of a person. In areas of this subzone, shrubs are an important source of fuel. The soil of the tundra zone is predominantly tundra-gley, characterized by gleying (see “Soils”). She is infertile. Frozen soils with a thin active layer are widespread. The fauna of the tundra is represented by reindeer, lemmings, arctic foxes, ptarmigan, and in summer - many migratory birds. Shrub tundra gradually turns into forest-tundra.

Forest-tundra . This is a transition zone between the tundra and the temperate forest zone. It is distributed in the Northern Hemisphere in North America and Eurasia. The climate is less severe than in the tundra: the average July temperature here is +10-14°C. The annual precipitation is 300-400 mm. There is more precipitation in the forest-tundra than evaporates, so the forest-tundra is characterized by excessive moisture; it is one of the most swampy natural zones. Snow cover lasts for more than six months. Floods on the rivers of the forest-tundra usually occur in the summer, since the rivers of this zone are fed by melt water, and the snow melts in the forest-tundra in the summer. Woody vegetation that appears in this zone grows along river valleys, since rivers have a warming effect on the climate of this zone. The forest islands consist of birch, spruce, and larch. The trees are stunted and in some places bent to the ground. The area of ​​forests increases in the forest-tundra as you move along it to the south. In the interfluves there are low-growing and sparse forests. Thus, the forest-tundra consists of an alternation of treeless shrub areas and open forests. Tundra (peat-swamp) or forest soils. The fauna of the forest-tundra is similar to the fauna of the tundra. It is also home to Arctic foxes, ptarmigan, snowy owls and a wide variety of migratory waterfowl. The forest-tundra contains the main winter pastures for reindeer and hunting grounds.

Temperate forests . This natural zone is located in a temperate climate zone and includes subzones taiga, mixed and deciduous forests, monsoon forests temperate zone. Differences in climatic features contribute to the formation of vegetation characteristic of each subzone.

Taiga (Turk.). This zone coniferous forests located in northern North America and northern Eurasia. The climate of the subzone ranges from maritime to sharply continental with relatively warm summers (from 10°C to 20°C), and the lower the winter temperatures, the more continental the climate is (from -10°C in northern Europe to -50°C in northeastern Europe). Siberia). Permafrost is widespread in many areas of Siberia. The subzone is characterized by excessive moisture and, as a consequence, swampy interfluve spaces. There are two types of taiga: light coniferous And thoseconiferous. Light coniferous taiga - These are the least demanding pine and larch forests in terms of soil and climatic conditions, the sparse crown of which allows the sun's rays to reach the ground. Pines, having an extensive root system, have acquired the ability to use nutrients from infertile soils, which is used to stabilize soils. This feature allows these plants to grow in areas with permafrost. The shrub layer of the light-coniferous taiga consists of alder, dwarf birches, polar birches, polar willows, and berry bushes. This type taiga is widespread in Eastern Siberia. Dark coniferous taiga - These are conifers, consisting of numerous species of spruce, fir, and cedar. This taiga, unlike the light-coniferous taiga, has no undergrowth, since its trees are tightly closed, and it is quite gloomy in these forests. The lower tier consists of shrubs (lingonberries, blueberries, blueberries) and dense ferns. This type of taiga is common in the European part of Russia and Western Siberia.

The soils of the taiga zone are podzolic. They contain little humus, but when fertilized they can provide a high yield. In the taiga of the Far East there are acidic soils.

The fauna of the taiga zone is rich. There are numerous predators here that are valuable game animals: otter, marten, sable, mink, weasel. Large ones include wolves, bears, lynxes, and wolverines. In North America, bison and wapiti deer used to be found in the taiga zone. Now they live only in nature reserves. The taiga is also rich in rodents, the most typical of which are beavers, muskrats, squirrels, hares, and chipmunks. The world of birds is very diverse.

Temperate mixed forests . These are forests with different tree species: coniferous-broad-leaved, small-leaved and pine. This zone is located in the north of North America (on the border of the USA and Canada), and in Eurasia it forms a narrow strip between the taiga and the zone of broad-leaved forests. The mixed forest zone is also found in Kamchatka and Far East. In the Southern Hemisphere, this forest zone occupies small areas in southern South America and New Zealand.

The climate of the mixed forest zone is maritime or transitional to continental (towards the center of the continent), summers are warm, winters are moderately cold (in a maritime climate with positive temperatures, and in a more continental climate up to -10 ° C). There is sufficient moisture here. The annual amplitude of temperature fluctuations, as well as annual quantity precipitation varies from oceanic regions to the center of the continent.

The diversity of vegetation in the mixed forest zone of the European part of Russia and the Far East is explained by differences in climate. For example, on the Russian Plain, where precipitation falls all year round thanks to the westerly winds coming from the Atlantic, European spruce, oak, elm, fir, and beech are common - coniferous-deciduous forests.

The soils in the mixed forest zone are gray forest and soddy-podzolic, while in the Far East they are brown forest.

The fauna is similar to the fauna of the taiga and the deciduous forest zone. Elk, sable, and bear live here.

Mixed forests have long been subject to severe deforestation and loss. They are best preserved in North America and the Far East, and in Europe they are cut down for agricultural land - field and pasture lands.

Temperate broadleaf forests . They occupy the east of North America, Central Europe, and also form a high-altitude zone in the Carpathians, Crimea and the Caucasus. In addition, isolated pockets of broad-leaved forests are found in the Russian Far East, Chile, New Zealand and central Japan.

The climate is favorable for the growth of deciduous trees with a wide leaf blade. Here, moderate continental air masses bring precipitation from the oceans (from 400 to 600 mm) mainly in the warm season. The average temperature in January is -8°-0°C, and in July +20-24°C.

Beech, hornbeam, elm, maple, linden, and ash grow in the forests. In the deciduous forest zone of North America, species are found that are not found on other continents. These are American oak species. Trees with a powerful spreading crown predominate here, often entwined with climbing plants: grapes or ivy. To the south there are magnolias. For European broad-leaved forests, oak and beech are the most typical.

The fauna of this natural zone is close to the taiga, but there are animals such as black bears, wolves, minks, raccoons, which are not typical for the taiga. Many animals of the broad-leaved forests of Eurasia are under protection, as the number of individuals is sharply declining. These include animals such as bison and Ussuri tiger.

The soils under broad-leaved forests are gray forest or brown forest. This zone has been heavily developed by humans, forests have been cleared over large areas, and the lands have been plowed. In its true form, the zone of broad-leaved forests has been preserved only in areas inconvenient for arable farming and in nature reserves.

Forest-steppe . This natural zone is located within the temperate climate zone and represents a transition from forest to steppe, with alternating forest and steppe landscapes. It is widespread in the Northern Hemisphere: in Eurasia from the Danube Lowland to Altai, further in Mongolia and the Far East; in North America, this zone is located in the northern Great Plains and western Central Plains.

Forest-steppes are naturally distributed within continents between forest zones, which here choose the most humidified areas, and the steppe zone.

The climate of the forest-steppes is moderate continental: winters are snowy and cold (from -5°C to -20°C), summers are warm (+18°C to +25°C). In different longitudinal zones, forest-steppe varies in precipitation (from 400 mm to 1000 mm). Humidification is slightly below sufficient, evaporation is very high.

In the forests that alternate steppes, broad-leaved (oak) and small-leaved tree species (birch) are more common, and conifers are less common. The soils of the forest-steppe are mainly gray forest soils, which alternate with chernozems. The nature of the forest-steppe zone has been greatly changed by human economic activity. In Europe and North America, the plowed area reaches 80%. Since this zone has fertile soils, wheat, corn, sunflowers, sugar beets and other crops are grown here. The fauna of the forest-steppe zone includes species characteristic of the forest and steppe zones.

The West Siberian forest-steppe with numerous birch groves-kolok (singular number - kolok) is specific. Sometimes they have an admixture of aspen. The area of ​​individual pegs reaches 20-30 hectares. Numerous forests, alternating with areas of steppes, create the characteristic landscape of Southwestern Siberia.

Steppes . This is a landscape with a herbaceous vegetation type, located in the temperate and partly subtropical zone. In Eurasia, the steppe zone extends in a latitudinal direction from the Black Sea to Transbaikalia; in North America, the Cordillera distributes air flows in such a way that the zone of insufficient moisture and with it the steppe zone are located from north to south along the eastern edge of this mountainous country. IN Southern Hemisphere The steppe zone is located within the subtropical climate of Australia and Argentina. Precipitation(from 250 mm to 450 mm per year) fall here irregularly and are insufficient for the growth of trees. Winter is cold, average temperature below 0°C, in some places down to -30°, with little snow. Summer is moderately hot - +20°С, +24°С, drought is common. Inland waters in the steppe are poorly developed, river flow is small, and rivers often dry up.

The undisturbed vegetation of the steppe is a thick grass cover, but undisturbed steppes throughout the world remain only in nature reserves: all steppes are plowed. Depending on the nature of vegetation in the steppe zone, three subzones are distinguished. They differ from each other in the predominant vegetation. This meadow steppes (bluegrass, bonfire, timothy), cereals and southern wormwood-cereals .

The soils of the steppe zone - chernozems - have a significant humus horizon, due to which they are very fertile. This is one of the reasons for the highly plowed area.

The fauna of the steppes is rich and diverse, but it has changed greatly under the influence of humans. Back in the 19th century, wild horses, aurochs, bison, and roe deer disappeared. Deer are pushed into forests, saigas - into virgin steppes and semi-deserts. Now the main representatives of the animal world of the steppes are rodents. These are gophers, jerboas, hamsters, voles. Bustards, little bustards, larks and others are occasionally seen.

The steppes and partly forest-steppes of the temperate and subtropical zones of North America are called prairies . Currently they are almost completely plowed. Part of the American prairies is dry steppes and semi-deserts.

The subtropical steppe on the plains of South America, located mainly in Argentina and Uruguay, is called pump . IN eastern regions, where precipitation falls from the Atlantic Ocean, there is sufficient moisture, but to the west the aridity increases. Most of the pampa territory is plowed, but in the west there are still dry steppes with thorny bushes, used as pastures for livestock.

Semi-deserts and temperate deserts . In the south, the steppes turn into semi-deserts, and then into deserts. Semi-deserts and deserts are formed in dry climates, where there is a long and hot warm period (+20-25°C, sometimes up to 50°C), strong evaporation, which is 5-7 times the amount of annual precipitation (up to 300 mm in year). Poor surface runoff, poor development inland waters, there are many drying riverbeds, the vegetation is not closed, sandy soils heat up during the day, but quickly cool down during the cool night, which contributes to physical weathering. The winds dry out the land very strongly here. Temperate deserts differ from deserts of other geographical zones more cold winter(-7°C-15°C). Deserts and semi-deserts of the temperate zone are widespread in Eurasia from the Caspian lowland to the northern bend of the Yellow River, and in North America - in the foothills and basins of the Cordillera. In the Southern Hemisphere, temperate deserts and semi-deserts are found only in Argentina, where they occur in broken areas in the interior and foothills. Among the plants found here are steppe feather grass, fescue, wormwood and solyanka, camel thorn, agave, and aloe. Animals include saigas, turtles, and many reptiles. The soils here are light chestnut and brown desert, often saline. Under conditions of sharp temperature fluctuations during the day with little moisture, a dark crust forms on the surface of deserts - a desert tan. It is sometimes called protective, as it protects rocks from rapid weathering and destruction.

The main use of semi-deserts is grazing livestock (camels, fine-wool sheep). Farming of drought-resistant crops is possible only in oases. Oasis (from the Greek name for several populated places in the Libyan Desert) is a place where tree, shrub and herbaceous vegetation grows in deserts and semi-deserts, in conditions of more abundant surface and ground moisture compared to neighboring areas and areas. The sizes of oases vary: from ten to tens of thousands of kilometers. Oases are centers of population concentration, areas of intensive agriculture on irrigated lands (Nile Valley, Fergana Valley in Central Asia).

Deserts and semi-deserts of the subtropical and tropical zones . These are natural areas located in both hemispheres, on all continents along tropical zones increased atmospheric pressure. Most often, semi-deserts of the subtropical zone are located in the transitional part from deserts to mountain steppes in the form of an altitudinal zone in the inland parts of the Cordillera and Andes of America, in western Asia, Australia and especially widely in Africa. The climate of these deserts and semi-deserts climatic zones hot: the average temperature in summer rises to +35°C, and in the coldest months of winter it does not fall below +10°C. Precipitation is 50-200 mm, in semi-deserts up to 300 mm. Sometimes precipitation occurs in short bursts of rain, and in some areas there may be no precipitation for several years in a row. With a lack of moisture, the weathering crust is very thin.

Groundwater lies very deep and can be partially saline. Only plants that can tolerate overheating and dehydration can live in such conditions. They have a deeply branched root system and small leaves or spines that reduce evaporation from the leaf surface. Some plants have leaves that are pubescent or covered with a waxy coating, which protects them from sunlight. In the semi-deserts of the subtropical zone, cereals are common and cacti appear. In the tropical zone, the number of cacti increases, agaves and sand acacias grow, and various lichens are common on the stones. A characteristic plant for the Namib Desert, located in the tropical zone of South Africa, is amazing plant Velwigia, which has a short trunk, from the top of which two leathery leaves extend. Welwigia can be up to 150 years old. The soils are gray soils, gravelly, gray-brown, they are not very fertile, since the layer of humus is thin. The fauna of deserts and semi-deserts is rich in reptiles, spiders, and scorpions. There are camels, antelopes, and rodents are quite widespread. Agriculture in semi-deserts and deserts of the subtropical and tropical zones is also possible only in oases.

Hardleaf forests . This natural zone is located within the subtropical zone of the Mediterranean type. They mainly grow in southern Europe, northern Africa, southwest and southeast Australia. Some fragments of these forests are found in California, Chile (south of the Atacama Desert). Hard-leaved forests grow in a mild, moderately warm climate with hot (+25°C) and dry summers and cool and rainy winters. The average precipitation is 400-600 mm per year with rare and short-lived snow cover. The rivers are mainly fed by rain, and floods occur in the winter months. In rainy winter conditions, grasses grow rapidly.

The fauna has been severely exterminated, but herbivorous and leaf-eating forms, many birds of prey and reptiles are characteristic. In the forests of Australia you can find the koala bear, which lives in trees and leads a nocturnal, sedentary lifestyle.

The territory of hard-leaved forests is well developed and has been significantly changed by human economic activity. Large areas of forest here have been cut down, and their place has been taken by oilseed plantations, orchards and pastures. Many tree species have hard wood, which is used as a building material, and oils, paints, and medicines are made from the leaves (eucalyptus). Large harvests of olives, citrus fruits, and grapes are harvested from the plantations of this zone.

Subtropical monsoon forests . This natural zone is located in the eastern parts of the continents (China, southeastern USA, eastern Australia, southern Brazil). It is located in conditions that are the most humid compared to other zones of the subtropical zone. The climate is characterized by dry winters and wet summers. Annual precipitation is greater than evaporation. The maximum amount of precipitation falls in summer due to the influence of monsoons, bringing moisture from the ocean. In the territory of monsoon forests, inland waters are quite rich, and fresh groundwater lies shallow.

Here, on red soils and yellow soils, tall mixed forests grow, among which there are evergreen and deciduous forests that shed their leaves during the dry season. Species composition plants may vary depending on soil conditions. The forests contain subtropical species of pines, magnolias, camphor laurel, and camellias. Swamp cypress forests are common on the flooded coasts of Florida in the United States and in the Mississippian lowlands.

The monsoon forest zone of the subtropical zone has been developed by man for a very long time. In place of cleared forests, there are field and pasture lands; rice, tea, citrus fruits, wheat, corn and industrial crops are grown here.

Forests of tropical and subequatorial zones . They are located along eastern Central America, the Caribbean islands, Madagascar, southeast Asia, and northeast Australia. There are clearly two seasons here: dry and wet. The existence of forests in the dry and hot tropical zone is possible only thanks to the precipitation that the monsoons bring from the oceans in summer. In the subequatorial belt, precipitation occurs in the summer, when equatorial air masses dominate here. Depending on the degree of moisture, forests of the tropical and subequatorial zones are distinguished permanently wet and seasonally wet(or variable-humid) forests. Seasonally wet forests are characterized by a relatively poor species composition of tree species, especially in Australia, where these forests consist of eucalyptus, ficus, and laurels. Often in seasonally wet forests there are areas where teak and sal grow. There are very few palm trees in the forests of this group. In terms of their species diversity of flora and fauna, permanently humid forests are close to equatorial forests. There are many palm trees, evergreen oaks, and tree ferns. There are many lianas and epiphytes of orchids and ferns. The soils located under forests are mainly lateritic. During the dry season (winter), most deciduous trees do not shed all their leaves, but some species remain completely bare.

Savannah . This natural zone is located mainly within the subequatorial climate, although it is also found within the tropical and subtropical zones. In the climate of this zone, the change in wet and dry seasons of the year is clearly expressed at consistently high temperatures (from + 15 ° C to + 32 ° C). As you move away from the equator, the period of the wet season decreases from 8-9 months to 2-3, and precipitation decreases from 2000 to 250 mm per year.

Savannas are characterized by a predominance of herbaceous cover, among which tall (up to 5 m) grasses dominate. Shrubs and single trees rarely grow among them. The grass cover near the borders with the equatorial belt is very thick and high, and near the borders with semi-deserts it is sparse. A similar pattern can be seen in trees: their frequency increases towards the equator. Among the savannah trees you can find a variety of palm trees, umbrella acacias, tree-like cacti, eucalyptus trees, and baobab trees that store water.

Savannah soils depend on the length of the rainy season. Closer to the equatorial forests, where the rainy season lasts up to 9 months, are red ferralite soils. Closer to the border of savannas and semi-deserts there are red-brown soils, and even closer to the border, where rain falls for 2-3 months, unproductive soils with a thin layer of humus are formed.

The fauna of savannas is very rich and diverse, as the high grass cover provides food for the animals. Elephants, giraffes, hippos, and zebras live here, which in turn attract lions, hyenas and other predators. The bird world of this zone is also rich. Sunbirds live here, ostriches - the largest birds on Earth, a secretary bird that hunts small animals and reptiles. There are a lot of termites in the savannah.

Savannas are widespread in Africa, where they occupy 40% of the continent's territory, in South America, Australia and India.

Tall grass savannas in South America, on the left bank of the Orinoco River, with a dense, mainly cereal grass cover, with individual specimens or groups of trees, are called llanos (from the Spanish plural of “plains”). The savannas of the Brazilian plateau, where the area of ​​intensive livestock farming is located, are called campos .

Today, savannas play a very important role in human economic life. Significant areas of this zone are plowed, grains, cotton, peanuts, jute, and sugar cane are grown here. In drier areas, livestock farming is developed. Many tree species are used on the farm, since their wood does not rot in water. Human activities often lead to desertification of savannas.

Equatorial rainforests . This natural zone is located in an equatorial and partly subequatorial climate. These forests are found in the Amazon, Congo, Malay Peninsula and Sunda Islands, as well as other smaller islands.

The climate here is hot and humid. Temperature all year round is +24-28°C. The seasons are not expressed here. Humid equatorial forests are located within an area of ​​low pressure, where, as a result of intense heating, upward air currents are formed and a lot of precipitation falls (up to 1500 mm per year) throughout the year.

On the coasts, where the wind from the ocean influences, precipitation falls even more (up to 10,000 mm). Precipitation falls evenly throughout the year. Such climatic conditions contribute to the development of lush evergreen vegetation, although, strictly speaking, trees change leaves: some shed them every six months, others after a completely arbitrary period, and others replace their leaves in parts. Flowering periods also vary, and are even more erratic. The most common cycles are ten and fourteen months. Other plants may bloom once every ten years. But at the same time, plants of the same species bloom at the same time so that they have time to pollinate each other. Plants in this zone have little branching.

Trees are wet equatorial forests They have disc-shaped roots, large leathery leaves, the shiny surface of which saves them from excessive evaporation and scorching rays of the sun, from the impact of rain jets during heavy downpours. Many leaves end in a graceful spine. It's a tiny drain. In plants of the lower tier, the leaves, on the contrary, are thin and delicate. The upper tier of equatorial forests is formed by ficus and palm trees. In South America, ceiba grows in the upper tier, reaching a height of 80 m. Bananas and tree ferns grow in the lower tiers. Large plants are entwined with vines. There are many orchids on the trees of equatorial forests, epiphytes are found, and sometimes flowers form directly on the trunks. For example, cocoa tree flowers. In the forest of the equatorial belt it is so hot and humid that favorable conditions are created for the development of moss and algae that cling to the crown and hang from the branches. They are epiphytes. Tree flowers in the crown cannot be pollinated by the wind because the air there is practically still. Consequently, they are pollinated by insects and small birds, which are lured by their brightly colored corolla or sweet scent. The fruits of the plants are also brightly colored. This allows them to solve the problem of transporting seeds. The ripe fruits of many trees are eaten by birds and animals; the seeds are not digested and, together with the droppings, end up far from the parent plant.

There are many native plants in equatorial forests. These are primarily vines. They begin their life on the ground in the form of a small bush, and then, tightly wrapping themselves around the stem of a giant tree, they climb up. The roots are in the soil, so the plant’s nutrition does not come from the giant tree, but sometimes the use of these trees for support by vines can lead to oppression and death. Some ficus trees are also “robbers”. Their seeds germinate on the bark of a tree, the roots tightly grip the trunk and branches of this host tree, which begins to die. Its trunk is rotting, but the roots of the ficus have become thick and dense and are already able to support themselves.

Equatorial forests are home to many valuable plants, such as the oil palm, from the fruits of which palm oil is obtained. The wood from many trees is used to make furniture and is exported in large quantities. This group includes ebony, the wood of which is black or dark green. Many plants of equatorial forests produce valuable fruits, seeds, juice, and bark, which are used in technology and medicine.

The equatorial forests of South America are called selva . Selva is located in the periodically flooded area of ​​the Amazon River basin. Sometimes, when describing moist equatorial forests, the name is used hylea , sometimes these forests are called jungle , although, strictly speaking, jungles are the forest thickets of South and Southeast Asia located within the subequatorial and tropical climate.