Amount of precipitation in mixed forests. Natural area of mixed and deciduous forests

Mixed and broad-leaved forests occupy a significantly smaller area in the forest zone than taiga. They grow in the west of the European part of Russia and in the south of the Far East.

In Siberia, there are no mixed or broad-leaved forests: there the taiga directly transforms into the steppe.

Mixed forests are more than 90% composed of coniferous and small-leaved species. These are mainly spruce and pine with an admixture of birch and aspen. Broad-leaved species in mixed forests few. Broad-leaved forests consist mainly of oak, linden, maple, elm, and in the southwestern regions - ash, hornbeam, and beech. The same breeds, but local species, are also represented in the Far East, where, in addition, Manchurian walnuts, grapes and vines grow.

The northern boundary of the zone lies approximately at 57° N. sh., above which the oak disappears, and the southern one adjoins the northern border of the forest-steppe, where the spruce disappears. This territory forms a kind of triangle with vertices in Leningrad, Sverdlovsk, Kyiv.

Mixed and broad-leaved forests are located mainly on the East European Plain, which has a flat, low-lying surface interrupted by a number of hills. Here are the sources, watersheds and basins of the largest rivers in the European part of Russia: the Volga, Dnieper, Western Dvina. On river floodplains, forests alternate with lush meadows, and on watersheds - with plowed fields.

Mixed forest

Flat lowlands due to proximity groundwater and limited drainage in some places are very swampy (Polesie, Meshchera). In addition to forest swamps and lakes, in some areas there are sandy soils, covered with pine. In forest clearings and swamps, many berry bushes and herbs grow.

Compared to the taiga, the climate is mixed and deciduous forests less severe. Winter is not so long and frosty, summer is warm. The average temperature in January is -10...-11°С, and in July + 18...+19°С. The average annual precipitation is from 800 to 400 mm. In general, the climate is transitional from maritime to continental in the direction from west to east. If in the Baltic states and Belarus the proximity of the sea smoothes out the difference between the air temperature of summer and winter, then in the Vyatka and Kama basin it becomes significant. In summer the air here warms up to +40°C, and in winter frosts reach -45°C. In all seasons of the year, winds carrying moisture from the Atlantic Ocean prevail.

The snow cover is less thick than in the taiga, with a layer from 20-30 (in the west) to 80-90 cm (in the east). It lasts on average 140-150 days a year, in the southern regions - 30-60 days.

With the onset of winter, life in forests, especially broad-leaved ones, comes to a standstill. Most insectivorous birds fly to warmer climes, and some animals go into hibernation or sleep (bats, hedgehogs, dormouse, badgers, bears). In spring and summer, all tiers of forests are inhabited by various animals.

Mixed forests

Natural areas of Russia / Mixed forests

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The mixed forest zone is located south of the taiga, mainly on the Russian Plain. This zone is the most widespread in foreign Europe; beyond its borders there are only the peninsulas of Southern Europe, where the vegetation is predominantly subtropical, and most of Scandinavia, mainly taiga. Entirely in the zone of mixed forests are Estonia, Latvia, Lithuania, Belarus, bordering Russia, and partially Ukraine. In Russia, the area it occupies gradually narrows to the east. Mixed forests extend beyond the Urals only in a narrow strip in Western Siberia; there are none in Eastern Siberia; mixed forests appear again in the south of the Far East. Proton axial bellows compensator price.

In the area where mixed forests are distributed, the climate is milder than in the taiga: mixed forests are located to the south. It is not as continental as in the taiga. In winter there are severe frosts, but forty degrees is already a rarity.

July temperatures with amazing constancy stay within the range of 17-19°, January temperatures steadily fall from +2 to -15°, taking with them the annual average from 10 to 1°. From this we can conclude that the narrowing of the zone of mixed forests to the east is associated not with summer temperatures, which are almost unchanged, but with winter ones. For this type of vegetation -5 °C is the limit.

Mixed forests, as their name suggests, consist of deciduous and coniferous trees. In addition to conifers and deciduous trees, found in the taiga, the mixed forest zone is characterized by broad-leaved trees - oak, linden, maple, ash and others. Broad-leaved trees are not as frost-resistant as taiga trees, and that is why there are almost no mixed forests in Siberia anymore. Sometimes a separate zone is identified to the south of mixed forests deciduous forests, but it’s hardly worth doing this, because it also contains areas of coniferous and birch forests.

The climate of the mixed forest zone allows agriculture, so forests have been cut down in many places, and fields are in their place. In relation to this zone, the expressive term “forest-landscape” is now used. The appearance of the zone also changed the industry - it is in this zone that the most industrially developed territories are located; therefore mixed forests, unlike arctic deserts, tundra and taiga, are no longer a natural, but a natural-anthropogenic zone.

The fauna of mixed forests is similar in composition to the fauna of the taiga, but since mixed forests are much more inhabited by humans, it is greatly impoverished; there are few animals left.

In the central part of European Russia, within the Russian Plain, mainly in the zone of mixed forests, but also going somewhat south, the Central Russian Upland is located. To the north is the Valdai Upland.

Zone of mixed and deciduous forests of Russia

Between them, forming a transverse ridge of east-northeast strike, is the Smolensk-Moscow Upland.

In mixed forests, on the Valdai Hills, the Volga begins to flow. The Dnieper also originates there, which then flows through the territory of Belarus and Ukraine and flows into the Black Sea.

The Volga is the largest river in European Russia and all of Europe. It flows into the Caspian Sea. The length of the river is more than three and a half thousand kilometers (it is considered 3531 km, but here, as for other rivers, a slight measurement error is possible). The total fall of the river is about 240 m.

From its source approximately to Kazan, the Volga flows in a general latitudinal direction - from west to east, and then turns south and flows in a meridional direction.

Large tributaries of the Volga are the Oka (right) and Kama (left). The Oka originates on the Central Russian Upland, the Kama - on one of the hills of the Cis-Urals. At the confluence of the Oka and the Volga stands the city of Nizhny Novgorod, somewhat higher than the confluence of the Kama - Kazan.

The Volga is blocked by the dams of many hydroelectric power plants and now represents a cascade of reservoirs, between which there are no or almost no sections of unchanged riverbed. There are no reservoirs only below the dam of the Volzhskaya Hydroelectric Power Station named after. XXII Congress of the CPSU (Volgograd). A large number of reservoirs makes the Volga regime regulated, that is, water flows become more uniform; However, in some places large spring floods are possible, which we hear about on radio and television almost every spring.

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Characteristics

The peculiarity of broad-leaved forests is that they can be divided into two distinct tiers. One of them is higher, the other is lower. These forests are shrubby, the existing grasses grow in three tiers, and the ground cover is represented by lichens and mosses.

Another characteristic feature is the light mode. In such forests, two light maxima are distinguished. The first is observed in the spring, when the trees are not yet covered with leaves. The second is in the fall, when the foliage thins. In summer, light penetration is minimal. The above-described regime explains the peculiarity of the grass cover.

The soil of deciduous forests is rich in organo-mineral compounds. They appear as a result of the decomposition of plant litter. Trees in broadleaf forests contain ash. There is especially a lot of it in the leaves - about five percent. Ash, in turn, is rich in calcium (twenty percent of the total volume). It also contains potassium (about two percent) and silicon (up to three percent).

Trees of broadleaf forests

Forests of this type are characterized by a rich variety of tree species. The latter can be counted here about ten. The broad-leaved forests of the taiga, for example, are not so rich in this regard. The reason is that the conditions of the harsh taiga climate are not so conducive to the growth and development of flora. Many tree species that are demanding on soil composition and climate simply will not survive in unfavorable conditions.

In the southern part Tula region there is a famous forest area. It gives a great idea of what broadleaf forests can be like. The soil of this area is favorable for the growth of trees such as small-leaved linden, Norway and field maples, common ash trees, elms, elms, wild apple and pear trees. Oaks and ash trees are the tallest, followed by Norway maples, elms and lindens. The lowest are field maples, wild pears and apple trees. As a rule, the dominant position is occupied by oak, and the remaining trees act as satellites.

Let us consider in more detail the above representatives of dendroflora.

Herbs

Plants of broad-leaved forests are characterized by large and wide leaf blades. For this reason they are called broad-grass oak forests. Some grasses grow in single specimens; they never form impenetrable thickets. Others, on the contrary, form a kind of carpet covering large spaces. Such herbs are dominant. Among them are common sedge, hairy sedge and yellow green grass.

Most of the herbaceous plants found in broadleaf forests are perennial. They live up to several decades. As a rule, their existence is maintained through vegetative propagation. They reproduce poorly by seeds. A characteristic feature of these plants is long underground and aboveground shoots that rapidly grow into different sides and actively occupying new areas of land.

The aboveground parts of most representatives of oak groves die off in autumn period. Only the roots and rhizomes in the soil overwinter. They contain special buds, from which new shoots form in the spring.

Exception to the Rule

Rare representatives of broad grass remain green both in winter and summer. Such plants include the following: hoofweed, green grass, hairy sedge.

Shrubs

As for these representatives of the flora, it is very difficult to find them in deciduous forests. They are simply not typical of oak forests, which cannot be said about coniferous forests, where shrubs grow everywhere. Most widespread got blueberries and lingonberries.

“Hasty” oak forest ephemeroids

These plants are of the greatest interest to specialists studying forest flora. Among them are spring guillemot, buttercup anemone, various types of corydalis and goose onion. These plants are usually small in size, but they develop very quickly. Ephemeroids rush to be born immediately after the snow cover melts. Some especially fast sprouts make their way even through the snow. After a week, maximum two, their buds are already blooming. After a few more weeks, the fruits and seeds ripen. After this, the plants lie down on the ground, turn yellow, after which the part of them that is above the ground dies. Moreover, this process occurs at the very beginning of the summer period, when, as it may seem, the conditions for growth and development are as favorable as possible. The secret is simple. Ephemeroids have their own rhythm of life, which differs from the peculiar development schedule of other plants. They bloom lushly only in the spring, and summer for them is the time to wither.

The period most conducive to their development is early spring. At this time of year in the forest there is maximum quantity light, since the bushes and trees have not yet acquired their thick green cover. In addition, during this period the soil is optimally saturated with moisture. As for high summer temperatures, ephemeroids do not need it at all. All these plants are perennial. They do not die after their aboveground part dries out. Living underground roots are represented by tubers, bulbs or rhizomes. These organs act as receptacles for nutrients, mainly starch. This is why stems, leaves and flowers appear so early and grow so rapidly.

Ephemeroids are widespread plants in broad-leaved oak forests. There are about ten species in total. Their flowers are painted in bright purple, blue, and yellow colors. During flowering, ephemeroids form a thick, beautiful carpet.

Mosses

Broad-leaved forests of Russia are home to various types of mosses. Unlike taiga forests, in which these plants form a dense green soil cover, in oak forests mosses do not cover the soil so widely. The role of mosses in deciduous forests is rather modest. The main reason is the fact that leaf litter from broad-leaved forests has a detrimental effect on these plants.

Fauna

Animals of the broad-leaved forests of Russia are ungulates, predators, insectivores, rodents and bats. The greatest diversity is observed in those areas that are untouched by humans. Thus, in deciduous forests you can see roe deer, wild boars, fallow deer, sika and red deer, and elk. The order of predators is represented by foxes, wolves, martens, stoats and weasels. Broadleaf forests, where wildlife is rich and varied, are home to beavers, squirrels, muskrats and nutria. In addition, these areas are inhabited by mice, rats, moles, hedgehogs, shrews, snakes, lizards and marsh turtles.

Birds of broad-leaved forests - larks, finches, warblers, tits, flycatchers, swallows, starlings. Crows, rooks, black grouse, woodpeckers, crossbills, jackdaws, and hazel grouse also live there. Birds of prey are represented by hawks, owls, owls, eagle owls and harriers. The marshes are home to waders, cranes, herons, gulls, ducks and geese.

In the past, broadleaf forests were inhabited by bison. Now, unfortunately, there are only a few dozen of them left. These animals are protected by law. They live in Belovezhskaya Pushcha (in the Republic of Belarus), in the Prioksko-Terrasny Nature Reserve (Russian Federation), in some Western European countries and in Poland. Several animals were transported to the Caucasus. There they coexist with bison.

The number of red deer has also undergone a change. They have become much smaller due to the barbaric actions of man. Massive plowing of fields has become disastrous for these beautiful animals. Deer can reach two and a half meters in length and three hundred and forty kilograms of weight. They tend to live in small herds of up to ten animals. In most cases, the female is dominant. Her offspring also live with her.

In autumn, males gather a kind of harem. Resembling the sound of a trumpet, their roar spreads three to four kilometers around. The most successful deer, having defeated their rivals in fights, can gather up to twenty females around them. This is how another type of reindeer herd is formed. At the beginning of the summer season, deer give birth to their young. They are born weighing eight to eleven kilograms. Up to six months they experience intensive growth. One-year-old males acquire horns.

Deer feed on grass, leaves and shoots of trees, mushrooms, lichens, reeds, and wormwood. But pine needles are not suitable for food. In conditions wildlife deer live about fifteen years. In captivity, this figure doubles.

Beavers are another inhabitant of deciduous forests. The most favorable conditions for them are observed in Europe, North America, and Asia. The maximum recorded weight of this animal is thirty kilograms, and its body length is one meter. Beavers are distinguished by a massive body and a flattened tail. Webbing between the toes of the hind legs helps guide water image life. Fur color can vary from light brown to black. By lubricating their fur with a special secretion, beavers protect themselves from getting wet. When immersed in water, the ears of this animal fold and the nostrils close. Economical consumption of air helps him stay under water for up to fifteen minutes.

Beavers prefer to settle on the banks of lakes and oxbow lakes, as well as slow-flowing rivers. They are attracted by abundant coastal and aquatic vegetation. It is a hole or a kind of hut, the entrance to which is located under the surface of the water. These animals build dams when the water level is unstable. Thanks to these structures, the flow is regulated, which allows water to enter the home. Gnawing branches and even large trees is easy for beavers. Thus, aspen trees five to seven centimeters in diameter lend themselves to these animals in two minutes. Their favorite food is reed. In addition, they are not averse to eating iris, water lilies, and water lilies. Beavers live in families. The young go in search of a mate in the third year of life.

Wild pigs are another typical inhabitant of deciduous forests. They have a huge head and a very strong long snout. The most powerful weapon of these animals is sharp triangular fangs that are curved up and back. Boars' vision is not very good, but this is compensated by excellent hearing and a keen sense of smell. Large individuals reach a weight of three hundred kilograms. The body of this animal is protected by dark brown bristles. It is very durable.

Boars are excellent runners and swimmers. These animals can swim across a body of water that is several kilometers wide. The basis of their diet is plants, but we can say that wild boars are omnivores. Their favorite delicacy is acorns and beech nuts; they will not refuse frogs, mice, chicks, insects and snakes.

Representatives of reptiles

Broad-leaved forests are inhabited by snakes, vipers, copperheads, godwits, green and viviparous lizards. Only vipers pose a danger to humans. Many people mistakenly believe that copperheads are also poisonous, but this is not the case. The most numerous reptiles of deciduous forests are snakes.

Relief features

The zone of broad-leaved forests (and mixed) in the European part of Russia forms a kind of triangle, the base of which is located at the western borders of the country, and the top abuts the Ural Mountains. Since this territory was covered more than once by continental ice, its topography is mostly hilly. The most obvious traces of the presence of the Valdai Glacier are preserved in the north-west. There, the zone of broad-leaved and mixed forests is characterized by chaotic piles of hills, steep ridges, closed lakes and basins. The southern part of the described territory is represented by secondary moraine plains, which were formed as a result of a decrease in the inclined surface of hilly areas. The relief is characterized by the presence of sandy plains of varying sizes. Their origin is water-glacial. They are undulating, and sometimes you can find pronounced sand dunes.

Russian Plain

This zone is located in the temperate climate zone. The climate there is relatively mild and humid. The soil of these areas is soddy-podzolic. The close location of the Atlantic Ocean determined the relief features. The river network in coniferous-deciduous forests is well developed. Reservoirs have a large area.

The activity of the waterlogging process is determined by the proximity of groundwater and the humid climate. The plants that dominate the grass cover have wide leaf blades.

Conclusion

Broad-leaved forests located in Europe are classified as endangered ecosystems. But just two or three centuries ago they were one of the most diverse on the planet and were located throughout most of Europe. Thus, in the sixteenth to eighteenth centuries they occupied an area equal to several million hectares. Today there are no more than one hundred thousand hectares.

At the beginning of the twentieth century, only fragments of the vast past remained intact. broadleaf belt. At the dawn of this century, attempts were made to grow oak trees in deserted territories. However, this turned out to be quite a difficult matter: the death of young oak groves was caused by constant droughts. At that time, research was carried out, led by the famous Russian geographer Dokuchaev. As a result, it was established that the failure to grow new trees was due to large-scale deforestation, since this forever changed the hydrology and climate of the area.

Today, secondary forests and artificial plantings grow in areas previously occupied by broad-leaved forests. They are dominated by coniferous trees. Unfortunately, as experts note, the dynamics and structure of natural oak forests cannot be restored.

Mixed forests are a natural area where a mixture of coniferous and deciduous trees grows (with an admixture of more than 5% of plants of another type). All life forms of vegetation occupy their ecological niches, forming a unique balance. The thicket with a diverse composition of trees is resistant to environmental influences, has a mosaic structure and diverse flora and fauna. If a favorable combination of coniferous and deciduous species has formed in the forest stand, such a diversity of forests can be more productive than a homogeneous one.

Characteristics and features of the natural zone of mixed forests.

See the geographical location of the mixed forest zone on the map of natural zones.

There are coniferous-small-leaved and coniferous-broad-leaved forests. The first ones, growing in the taiga regions of Eurasia, do not last long. They precede the change from small-leaved groves to native coniferous forests or broad-leaved oak forests. And coniferous-deciduous thickets are considered a stable natural formation. Such ecosystems develop cyclically, with a temporary predominance of coniferous or a number of deciduous species. Depending on the climate, terrain, soil and hydrological regime, the composition of trees varies. Spruce, pine, fir, oak, beech, linden, maple, ash, aspen, birch and other species in various combinations are often found.

Mixed forests are formed in the temperate climate zone ( temperate continental climate) with a clear change of seasons - relatively hot summer and cold winter. The average annual precipitation here usually reaches 600-700 mm. With insufficient evaporation, excess humidity and swampy areas occur.

Coniferous-deciduous forests grow in North America (most of Canada, northern USA), in the western part of South America, Eurasia (Europe, Russia, Central Asia), Great Britain, northern Japan. This natural zone in the southern direction gives way to forest-steppe or deciduous forest, and to the north it turns into coniferous.

Under mixed forests with a predominant share of deciduous trees, gray and brown forest soils. They are characterized by a higher content of humus than in podzolic taiga varieties. If the main species are coniferous species, then soddy-podzolic soils of low fertility, with high acidity and excess moisture predominate.

In Russia, there is no accurate accounting of the number of mixed forests. On average, they account for up to half total area forest fund of the country. They grow all over Western Europe, reaching Vostochnaya, where they border the taiga along a conventional line from St. Petersburg to Nizhny Novgorod. Further to the east, a narrow strip stretches to the Urals.

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A mixed forest is an area in which deciduous and coniferous trees. If the admixture of tree species is more than 5% of the total flora, we can already talk about a mixed type of forest.

The mixed forest forms a zone of coniferous-deciduous forests, and this is a whole natural zone characteristic of forests in the temperate zone. There are also coniferous-small-leaved forests, which are formed in the taiga as a result of the restoration of previously cut down pines or spruces, which begin to displace different types birch and aspen.

Main characteristics

(Typical mixed forest)

Mixed forests almost always coexist with broad-leaved forests in the south. In the northern hemisphere they also border the taiga.

The following types of mixed forests in the temperate zone are distinguished:

coniferous-deciduous;
secondary small-leaved with the addition of coniferous and broad-leaved species;
mixed, which is a combination of deciduous and evergreen species.

Subtropical mixed foxes are distinguished by a combination of laurel leaves and conifers. Any mixed forest is distinguished by a pronounced layering, as well as the presence of areas without forest: the so-called opoles and woodlands.

Location of zones

Mixed forests, a combination of coniferous and broad-leaved species, are found on the East European and West Siberian plains, as well as in the Carpathians, the Caucasus and the Far East.

In general, both mixed and broad-leaved forests do not occupy as large a share of the forest territory of the Russian Federation as coniferous taigas. The fact is that such ecosystems do not take root in Siberia. They are traditional only for the European and Far Eastern regions and at the same time grow in broken lines. Pure mixed forests are found south of the taiga, as well as beyond the Urals to the Amur region.

Climate

Forest plantations mixed type They have cold but not very long winters and hot summers. Climatic conditions are such that precipitation falls no more than 700 mm per year. The moisture coefficient is increased, but can change throughout the summer. In our country, mixed forests stand on soddy-podzolic soil, and in the west - on brown forest soil. As a rule, winter temperatures do not fall below – 10˚C.

Broad-leaved forest plantations are characterized by a humid and moderately humid climate, where precipitation is distributed evenly throughout the year. The temperatures are quite high, and even in January it never gets colder than -8˚C. Increased humidity and abundant heat stimulate the work of bacteria and fungal organisms, due to which the leaves quickly decompose and the soil maintains maximum fertility.

Features of the plant world

Features of biochemical and biological processes cause the consolidation of species diversity as they move towards broad-leaved species. European mixed forests are distinguished by the obligatory presence of pine, spruce, maple, oak, linden, ash, elm, and among the shrubs the leaders are viburnum, hazel, and honeysuckle. Ferns are very common as herbs. Caucasian mixed forests contain large quantities of beech and fir, while the Far Eastern forests contain birch, walnut, hornbeam, and larch. These same forests are distinguished by a variety of vines.

Representatives of fauna

Mixed forests are home to those animals and birds that are generally considered typical for forest conditions. These are moose, foxes, wolves, bears, wild boars, hedgehogs, hares, badgers. If we talk about individual broad-leaved forests, the species diversity of birds, rodents and ungulates is especially striking here. Roe deer, fallow deer, deer, beavers, muskrats and nutria are found in such forests.

Economic activity

The temperate natural zone, including mixed forests, has long been developed by local residents and is densely populated. An impressive part of the forest plantations was cut down several centuries ago, which is why the composition of the forest has changed and the proportion of small-leaved species has increased. In place of many forests, agricultural areas and settlements appeared.

Broad-leaved forests can generally be considered rare forest ecosystems. After the 17th century, they were cut down on a large scale, largely because wood was needed for the sailing fleet. Also, broad-leaved forests were actively cut down for arable land and meadows. Oak plantations have suffered especially badly from such human activity, and it is unlikely that they will ever be restored.

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Mixed forests

Mixed forests - a natural zone of temperate climate zone. The mixed forest usually borders on the south with a zone of broad-leaved forests. It is typical for Northern Hemisphere and is found in eastern North America: northern USA - southern Canada, as well as in Eurasia. Here mixed forests stretch from the borders Eastern Europe: Poland and Belarus to Western Siberia. Their northern border with the taiga roughly runs through St. Petersburg, Yaroslavl and Yekaterinburg. Mixed forest is much more adapted to cold climatic conditions than broad-leaved forest. Here the vegetation can already withstand cold winters with average temperatures below -16°C and even frosts of -30°C. Summer here is quite warm with average values from +16 to +24°C. The annual precipitation is within 500 mm and decreases inland.

The vegetation of mixed forests, in addition to broad-leaved species: oak, maple, linden, poplar, is represented by small-leaved and coniferous trees, the percentage of which increases to the north of the natural zone. Birch, alder, willow, rowan, spruce, and pine are common here. Most of the trees are deciduous, which is an adaptation to cold winters temperate zone. At the same time, coniferous trees, with the exception of larch, remain green all year round. The soils of mixed forests in the south are gray forest, in the north they are soddy-podzolic; they are not characterized by high fertility, however, they are suitable for growing plants. The fauna of the forests is represented by mammals. Moose, foxes, wolves, bears, wild boars, beavers, otters, and lynx live here. Among the smaller ones: weasel, ferret, squirrel. Skunks, opossums, and deer are also found in North America.

The mixed forest has been developed by man; its vast areas have been cleared and are now arable land and meadows. There are now few large tracts left; they are mostly crossed by transport highways, cut down and occupied by populated areas.

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Mixed forests of Russia. Plants and animals of a mixed forest. Soils of mixed forests

Broad-leaved and mixed forests make up a significantly smaller percentage of Russia's forest zone than coniferous taiga. In Siberia they are completely absent. Broad-leaved and mixed forests are typical for the European part and the Far Eastern region of the Russian Federation. They are formed by deciduous and coniferous trees. They not only have a mixed composition of forest stands, but are also distinguished by the diversity of the animal world and resistance to negative influences environment, mosaic structure.

Types and layers of mixed forests

There are coniferous-small-leaved and mixed-deciduous forests. The former grow mainly in continental regions. Mixed forests have a clearly visible layering (changes in the composition of the flora depending on height). The uppermost tier consists of tall spruce, pine, and oak trees. Birch, maple, elm, linden, wild pear and apple trees, younger oak trees and others grow somewhat lower. Next come lower trees: mountain ash, viburnum, etc. The next tier is formed by shrubs: viburnum, hazel, hawthorn, rose hips, raspberries and many others. Next come the semi-shrubs. At the very bottom grow grasses, lichens and mosses.

Intermediate and primary forms of coniferous-small-leaved forest

An interesting feature is that mixed-small-leaved tracts are considered only an intermediate stage of the formation of a coniferous forest. However, they can also be indigenous: massifs of stone birch (Kamchatka), birch groves in forest-steppes, aspen bushes and swampy alder forests (southern European part of the Russian Federation). Small-leaved forests are very light. This contributes to the lush growth of grass and its diversity. Coniferous-mixed broad-leaved forest, on the contrary, belongs to stable natural formations. It is distributed in the transition zone between taiga and broad-leaved types. Coniferous-deciduous forests grow on the plains and on the lowest mountain belt with moderate and humid climatic conditions.

Zone of mixed and deciduous forests

Coniferous-deciduous forests grow in warmer temperate regions. They are distinguished by the diversity and richness of their grass cover. They grow in intermittent stripes from the European part of the Russian Federation to the Far East. Their landscapes are favorable for people. To the south of the taiga there is a zone of mixed forests. They are distributed throughout the entire area of the East European Plain, as well as beyond the Urals (all the way to the Amur region). A continuous zone is not formed.

The approximate border of the European area of deciduous and mixed forests in the north lies at 57° N. w. Above it, oak (one of the key trees) almost completely disappears. The southern one almost touches northern border forest-steppes, where spruce completely disappears. This zone is a triangle-shaped area, two of whose peaks are located in Russia (Ekaterinburg, St. Petersburg), and the third in Ukraine (Kyiv). That is, as you move away from the main zone to the north, broad-leaved and mixed forests gradually leave the watershed areas. They prefer river valleys that are warmer and protected from icy winds with exposure to carbonate rocks. Along them, forests of broad-leaved and mixed types gradually reach the taiga in small tracts.

The East European Plain mainly has low-lying and flat terrain, with only occasional hills. Here are the sources, basins and watersheds of the largest Russian rivers: Dnieper, Volga, Western Dvina. On their floodplains, meadows alternate with forests and arable lands. In some regions, lowlands, due to the proximity of groundwater, as well as limited flow, are extremely swampy in places. There are also areas with sandy soils where pine trees grow. Berry bushes and herbs grow in swamps and clearings. This area is most suitable for coniferous-deciduous forests.

Human influence

Broad-leaved and mixed forests have been subject to various impacts from people for a long time. Therefore, many massifs have changed greatly: the indigenous vegetation is either completely destroyed, or partially or completely replaced by secondary rocks. Nowadays, the remnants of broad-leaved forests that have survived under severe anthropogenic pressure have a different structure of changes in the flora. Some species, having lost their place in indigenous communities, grow in anthropogenically disturbed habitats or have taken intrazonal positions.

Climate

The climate of mixed forests is quite mild. It is characterized by relatively warm winters (on average from 0 to –16°C) and long summers (16-24°C) compared to the taiga zone. Average annual precipitation is 500-1000 mm. It everywhere exceeds evaporation, which is a feature of the clearly expressed leaching water regime. Mixed forests have such characteristic feature, as a high level of grass development. Their biomass averages 2-3 thousand c/ha. The level of litter also exceeds the biomass of the taiga, however, due to the higher activity of microorganisms, the destruction organic matter goes much faster. Therefore, mixed forests have a smaller thickness and a higher level of litter decomposition than taiga coniferous forests.

Soils of mixed forests

The soils of mixed forests are diverse. The cover has a rather variegated structure. On the territory of the East European Plain, the most common type is sod-podzolic soil. It is a southern variety of classic podzolic soils and is formed only in the presence of soil-forming rocks of the loamy type. Sod-podzolic soil has the same profile and similar structure. It differs from podzolic in the less massive litter (up to 5 cm), as well as in the greater thickness of all horizons. And these are not the only differences. Soddy-podzolic soils have a more pronounced humus horizon A1, which is located under the litter. Appearance it differs from a similar layer of podzolic soils. The upper part contains the rhizomes of the grass cover and forms the turf. The horizon can be painted in various shades of gray and has a loose structure. The thickness of the layer is 5-20 cm, the proportion of humus is up to 4%. The upper part of the profile of these soils has an acidic reaction. As you go deeper, it becomes even smaller.

Soils of mixed-deciduous forests

Gray forest soils of mixed-deciduous forests are formed in inland regions. In Russia they are distributed from the European part to Transbaikalia. In such soils, precipitation penetrates to great depths. However, groundwater horizons are often very deep. Therefore, soaking the soil to their level is typical only in heavily moistened areas.

Mixed forest soils are better suited for agriculture than taiga soils. In the southern regions of the European part of the Russian Federation, arable lands account for up to 45% of the area. Closer to the north and taiga, the share of arable land gradually decreases. Farming in these regions is difficult due to severe leaching, swampiness and bouldering of the soil. To obtain good harvests, a lot of fertilizer is required.

General characteristics of fauna and flora

The plants and animals of the mixed forest are very diverse. In terms of species richness of flora and fauna, they are comparable only to tropical jungles and are home to many predators and herbivores. Here on tall trees Squirrels and other living creatures settle in, birds make nests on the treetops, hares and foxes make burrows at the roots, and beavers live near the rivers. The species diversity of the mixed zone is very high. Both the inhabitants of the taiga and deciduous forests, as well as the inhabitants of the forest-steppes, feel comfortable here. Some are awake all year round, while others hibernate during the winter. Plants and animals of a mixed forest have a symbiotic relationship. Many herbivores feed on various berries, which are abundant in mixed forests.

Trees of mixed forest

Mixed-small-leaved forests consist of approximately 90% coniferous and small-leaved tree species. There are not many broad-leaved varieties. Along with coniferous trees, aspens, birches, alders, willows, and poplars grow in them. There are more birch forests in this type of massif. As a rule, they are secondary - that is, they grow in forest fires, clearings and clearings, and old unused arable land. In open habitats, such forests regenerate well and grow quickly in the first years. The expansion of their areas is facilitated by economic activity person.

Coniferous-deciduous forests mainly consist of spruce, linden, pine, oak, elm, elm, maple, and in the southwestern regions of the Russian Federation - beech, ash and hornbeam. The same trees, but of local varieties, grow in the Far Eastern region along with grapes, Manchurian walnuts and vines. In many ways, the composition and structure of the forest stand of coniferous-broad-leaved forests depends on climatic conditions, topography and soil-hydrological regime of a particular region. In the North Caucasus, oak, spruce, maple, fir and other species predominate. But the most diverse in composition are the Far Eastern forests of the coniferous-broad-leaved type. They are educated cedar pine, whitebark fir, Ayan spruce, several varieties of maple, Manchurian ash, Mongolian oak, Amur linden and the above-mentioned local species of vegetation.

Species diversity of the animal world

Of the large herbivores, mixed forests are inhabited by elk, bison, wild boar, roe deer and sika deer (the species was introduced and adapted). Rodents present forest squirrels, martens, stoats, beavers, chipmunks, otters, mice, badgers, minks, black ferrets. Mixed forests abound a large number bird species. The following are many of them, but not all: oriole, nuthatch, siskin, fieldfare, goshawk, hazel grouse, bullfinch, nightingale, cuckoo, hoopoe, gray crane, goldfinch, woodpecker, black grouse, chaffinch. More or less large predators are represented by wolves, lynxes and foxes. Mixed forests are also home to hares (hares and hare), lizards, hedgehogs, snakes, frogs and brown bears.

Mushrooms and berries

Berries are represented by blueberries, raspberries, lingonberries, cranberries, blackberries, bird cherry, strawberries, stoneberries, elderberries, rowan berries, viburnum, rose hips, and hawthorn. In forests of this type there are a lot of edible mushrooms: boletuses, white mushrooms, valui, chanterelles, russula, honey mushrooms, milk mushrooms, boletus, boletus, various rows, boletus mushrooms, moss mushrooms, saffron milk caps and others. Some of the most dangerous poisonous macromycetes are fly agarics and toadstools.

Shrubs

The mixed forests of Russia abound in shrubs. The undergrowth layer is unusually developed. Oak tracts are characterized by the presence of hazel, euonymus, wolf's bast, forest honeysuckle, and in northern zone– buckthorn brittle. Rose hips grow on the edges and in open forests. In forests of the coniferous-broad-leaved type, there are also liana-like plants: fence grass, climbing hops, bittersweet nightshade.

Herbs

The grasses of mixed forests (especially the coniferous-broad-leaved type) have a large species diversity, as well as a complex vertical structure. The most typical and widely represented category is mesophilic nemoral plants. Among them, representatives of oak forest broad grass stand out. These are plants in which the leaf blade has a significant width. These include: perennial woodweed, common gooseberry, obscure lungwort, May lily of the valley, European hoofed grass, hairy sedge, yellow green chickweed, lanceolate chickweed, nomad (black and spring), amazing violet. Cereals are represented by bluegrass, giant fescue, forest reed grass, short-legged pinnate grass, spreading boron and some others. The flat leaves of these plants are an adaptation option to the specific phytoenvironment of coniferous-deciduous forests.

In addition to the above-mentioned perennial species, these tracts also contain grasses of the ephemeroid group. They postpone their growing season to spring, when the lighting is maximum. After the snow melts, it is the ephemeroids that form a beautifully blooming carpet of yellow anemones and goose onions, purple corydalis and lilac-bluish woodlands. These plants go through their life cycle in a couple of weeks, and when the leaves of the trees bloom, their above-ground parts die off over time. They experience an unfavorable period under a layer of soil in the form of tubers, bulbs and rhizomes.

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coniferous, mixed, broad-leaved and small-leaved

Forests make up just over 45% of Russia's area, and almost a quarter of the world's total forest area. There are much fewer of them in the European part of the country than in the Asian part. The most common forest-forming tree species are spruce, larch, pine, cedar, oak, maple and hornbeam. The forests contain many berry bushes, mushrooms, valuable herbs, and are also home to countless species of fauna. Deforestation leads to the reduction of forest areas and the threat of extinction of many animals. In the 21st century, it is very important to be able to reproduce forest resources, which play a major role in regulating the climate on the planet.

Map of forest cover of Russian territory in %

Russia is the largest country in the world, and for this reason, its territory is home to many natural areas in which plants grow. various types trees. The forests of Russia, depending on the predominance of certain tree species, are divided into four main types: 1) coniferous forests; 2) broad-leaved forests; 3) mixed forests; 4) small-leaved forests. Below we will look at each of these forest types in more detail.

Characteristics of coniferous forests in Russia

Coniferous forests are located in the natural taiga zone and occupy about 70% of the country's total forest area. This area is known for low temperatures and humid air. Coniferous forests stretch from the western borders of Russia to the Verkhoyansk Range. The main forest-forming species are spruce, pine, fir and larch.

In harsh winter conditions, you can most often find mixed forests: dark coniferous and light coniferous. Evergreen tree species develop well. Their photosynthesis begins in the spring with the onset of favorable weather conditions. There is practically no undergrowth in the taiga. There is podzolic soil and many swamps. Conifers shed needles, which, when decomposed, release compounds that are toxic to many plants into the ground. The ground is usually covered with mosses and lichens. Shrubs and flowers mainly grow along river banks; there are very few of them in dark places in the forest. There are lingonberries, junipers, rowan, blueberries and curly lilies.

It is weather conditions that determine the flora of Russia. In the zone coniferous forests Temperate continental climate prevails. Winters are dry and cold, and last on average six months. Short summer warm and humid, with numerous cyclones. As a rule, only one month is allocated for autumn and spring. Conifers are not picky about temperature changes.

Representatives of the animal world feed on moss, lichens, bark and cones. The high forest crown protects animals from the winds, and the branches provide an opportunity to build nests. Typical representatives of the fauna of coniferous forests are the vole, the mountain hare, the weasel, and the chipmunk. From large mammals one can note the Siberian tiger, brown bear, lynx and elk, and from the forest-tundra zone it comes to coniferous forests reindeer. Eagles and vultures soar in the sky.

Coniferous wood is considered one of the most valuable. Its approximate reserve is 5.8 billion cubic meters. In addition to logging, oil, gold and gas are extracted in the taiga. Coniferous forests of Russia are a huge forest area. It suffers from forest fires and uncontrolled logging. Rare animals are dying due to negative human activities. There are many nature reserves, but for the full restoration of forests it is necessary to properly organize protection and rationally use the country’s forest resources.

Characteristics of broad-leaved forests of Russia

Broadleaf forest/Wikipedia

The territory of broad-leaved forests extends from the western border of Russia to the Ural Mountains. The main tree species are beech, oak, elm, linden, maple and hornbeam. Forests are multi-tiered: the upper tier is replaced by the canopy and undergrowth, which, in turn, are replaced by herbaceous plants and forest litter. The soil is covered with mosses. There are areas where lush crowns completely exclude undergrowth. When leaves fall, they decompose and form humus. The soil in the undergrowth is rich in organomineral compounds.

The forests are located in the temperate continental zone. The weather here is much warmer than in the neighboring taiga. Summer lasts four months, the average temperature for the season is +10°C. This promotes the growth of broad-leaved tree species. The climate is humid and there is a lot of rainfall. The average monthly temperature in January drops to -16ºС. Maximum precipitation occurs in summer; there is no deep snow cover.

The leaves cannot survive the cold period of the year and fall off in mid-autumn. A dense cover of foliage, branches and bark protects the ground from excessive evaporation. The soil is rich in microelements and provides trees with everything they need. Fallen leaves for the winter cover the root system, protect it from the cold and stimulate the roots for further growth.

The composition of the animal world in the European part is somewhat different from the Far Eastern forests. Asian lands are covered with thickets of fern, ilmen and linden. The dense thickets are home to elk, Himalayan bear and Ussuri tiger. Cottonmouth, viper and Amur snake are common reptiles. European broadleaf forests are home to wild boar, elk, deer, wolves, weasels, beavers, muskrats and nutria. Mice, lizards, snakes, moles and hedgehogs also live there. Birds are represented by black grouse, eagle owls, owls, starlings, swallows and larks.

The zone of broad-leaved forests has long been developed by humans, especially in the west of Russia. People had to significantly reduce the green area for grazing, crop production and city construction. Trees are the main raw material for the logging industry. Processing of recyclable materials has been established. The subsoil is rich in minerals, and in large rivers There is potential for the development of hydroelectric power.

The forest area is being significantly reduced, while forests are being cut down on the same scale. Due to anthropogenic influence, plants and animals listed in the Red List are becoming extinct. Unscrupulous entrepreneurs are cutting down huge areas of forests. To preserve natural complexes, several nature reserves and national parks were created, but this is not enough. Broad-leaved tree species grow relatively quickly. It is necessary to organize the planting of seedlings in the areas of cleared forests, as well as to carefully use the remaining forest areas.

Characteristics of mixed forests in Russia

Mixed forests are located in the regions of the Russian Plain, West Siberian Plain, Amur Region and Primorye. A variety of tree species are found in this area. These forests are characterized by a pronounced layering. Poplars, pines and spruce trees stretch towards the light. Below them rise maples, elms, lindens and oaks. The layer of shrubs is represented by hawthorn, rose hips, raspberries and blackberries. The soil is covered with lichens, mosses and low grasses.

Trees in mixed forests can more easily withstand the harsh climate than those in neighboring broad-leaved forests. The vegetation can withstand frosts down to -30ºС. The amount of precipitation depends on the region. There is more snow in European forests than in the Far East. The maximum amount of precipitation occurs in the warm season. Summers are mild and humid. The climate changes from maritime to continental, from west to east.

Continuous renewal of green mass helps to nourish trees and cleanse the earth of unnecessary substances. Forest inhabitants use resources of all tiers as a food supply. Conifer seeds attract birds, rodents eat nuts, and larvae under the bark provide food for insectivorous birds.

Numerous once-numerous animals were exterminated as a result of uncontrolled hunting. You can also see roe deer and wild boar. The bison and red deer are preserved only in nature reserves. A well-known predator of mixed forests is common fox. The badger lives in the European part. Squirrel, mink, dormouse, marten, forest cat, brown bear are considered common representatives of the fauna of mixed forests. The world of birds is also diverse, especially many woodpeckers, wood grouse, wild pigeons, finches and robins.

Valuable timber reserves are located in the Asian part. Manchurian walnut, Korean cedar, and whole-leaf fir are famous for their strength and resistance to rotting. Eleutherococcus and Schisandra are used for medicinal purposes. Logging activities are carried out in Europe.

Mixed forests have suffered more than others at the hands of man. This has led to a number of environmental problems. The need for agricultural land has led to the clearing of large parts of the area. Due to the draining of the swamps, the ecosystem has changed. Height settlements, especially in the west, has led to a 30% reduction in forest cover.

The foliage of trees perfectly processes carbon dioxide. Deforestation, which has reached gigantic proportions, has destroyed millions of hectares. Because of this, harmful gases accumulate in the atmosphere, creating a greenhouse effect. Hundreds of animal species and flora disappears from the face of the earth. Happens due to people's fault forest fires, radically changing the ecosystem. On rare species animals are hunted illegally. Resources are almost depleted; only interaction between the state and citizens can stop the process of destruction of the country's mixed forests.

Characteristics of small-leaved forests in Russia

The zone of small-leaved forests extends from the East European Plain to the Far East. The forests stretch in a narrow strip, at times replacing broad-leaved trees. Small-leaved trees play the role of a second forest, replacing broad-leaved and coniferous trees.

The main forest-forming species are birch, alder and aspen. Their foliage is distinguished by a narrow leaf blade. Trees are undemanding to climate and soil quality. Birch trees are most widespread.

Trees often grow in places where there are fires or deforestation. Alder reproduces by shoots, and aspen by root suckers. Where there were no forests, trees grow by seed. Amazing feature the ability to accumulate moisture is considered. Thickets of alder and birch block the path of fire and prevent it from spreading to noble species.

The fauna is shaped by the influence of indigenous trees. A lot of birds. Mammals include hares, lynxes, moose and squirrels. Strips of small-leaved forest alternating with farmland are favorite places for raccoon dogs.

Secondary forests contribute to the restoration of green areas, although complete rehabilitation takes about 180 years. They act as a fire buffer. It remains to be hoped that small-leaved forests will contribute to the reorganization of the country's forest resources.

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Mixed and broad-leaved forests of Russia

Mixed forests differ from other types in that different tree species can be found on their territory. For example, not only deciduous but also coniferous forests grow here. While broad-leaved forests consist mainly of certain species.

The climatic conditions in these areas are characterized by moderate temperatures and are quite acceptable for the growth of various tree species.

Features of mixed forests in Russia

This is the richest natural resources a forested area found in only a few countries. For our state, the development and cultivation of species growing in such forests is an important component of the successful development of the entire industry of the country.

Mixed forests are considered as such and belong to this type only when the admixture of two varieties of tree species: deciduous and coniferous is about 5% of the total volume of the forest.

In the territories of our country where mixed forests grow, it is generally quite warm and there is no prolonged precipitation. Summer here is not characterized by abnormal heat and sudden changes in temperature conditions. While in winter there will be no heavy snowfalls or natural disasters associated with sharp drops in temperature.

Mixed forests are characterized by:

temperate climate,
the presence of an optimal moisture coefficient,
the growth of a wide variety of trees within one forest area.

Closer to the south of the natural zone where mixed forests grow, there are tracts dominated by broad-leaved tree species. After all, most of the north is occupied by taiga. The climatic conditions of these territories allow only the most “hardy” tree species to grow here.

The soils of mixed forests are particularly fertile. The constant renewal of nature helps to feed them and cleanse the earth of substances it does not need. For example, soil that has already been cultivated by humans needs renewal. It will take several years for the forest to expand again.

If we consider mixed forests from the point of view of the history of their appearance, then in the past they were present on large areas. However, due to human activity and the development of urban infrastructure, forests have significantly reduced their volume.

Despite the fact that our country has enormous advantages in terms of development of the timber industry, every year the areas of mixed forests and other varieties of these natural resources are significantly reduced.

This leads to natural disasters, because only a strong root system of trees can hold back strong winds and prevent floods. Mixed forests represent a whole complex of all kinds of natural elements and resources united in one area.

Only these massifs create a special natural zone, represented by coniferous-deciduous forests. There are only a few places in the world whose climate allows such a variety of trees to be collected in one area. At the same time, so that they can coexist peacefully with each other, in fact, in the same climatic zone.

But timber production on these lands is permitted only after receiving the relevant documents, first approved by the state. Such natural areas where forests grow are considered the property of the state. Such laws were passed in order to:

reduce unauthorized tree felling,
allow mixed forests to freely expand their territories,
take care of improving the environmental situation in Russia by increasing the volume of forests.

The areas of coniferous forests have recently decreased significantly. But the situation is saved by coniferous-small-leaved forests. They allow these natural areas to quickly restore their natural potential. This occurs due to the growth of trees that have already been cut down, the so-called young forests.

They shorten the stages of transition from forests damaged by logging to full restoration of the forest. In fact, birch and pine trees grow in place of felled pine and spruce trees, which are the most sought-after natural resources in the timber industry.

The mixed forests of Europe, like the forests that predominate in our country, are located in almost the same natural zone. Therefore, the main species forming forests belonging to this variety are: spruce and oak. It is rare in our time to find an array where, among all tree species, ash or maple stands out the most.

After people began to develop these lands, most breeds simply disappeared from these places. Their complete restoration requires years and organization of work to plant the required number of seedlings, which will become the basis for the future forest.

Nature is unique because it is capable of creating such diverse forest areas. They differ from each other not only in the shape of the leaves, but also in a whole complex of various characteristics. Mixed forests cannot be formed through human efforts and properly planted trees.

It is almost impossible to artificially create such an ecosystem that functions at the expense of its own resources and is completely autonomous. Therefore, a person has no choice but to preserve the wealth that already exists in our country.

It is possible to create forests artificially for only one purpose - further cutting down and harvesting of already processed natural material. Sometimes trees are planted to purify water in nearby rivers or to create an additional natural “filter” for air purification.

Such synthetically created forests lend themselves well to felling, and their potential can be restored by planting new seedlings. Thus, nature manages to replenish the volume of forest resources that has already been developed in the forest.

Mixed forests are very difficult to grow under artificial conditions. That is, if you simply randomly plant several trees on the territory you need for subsequent felling, only some species will be able to grow fully.

After all, in fact, a mixed forest is a unique system that has existed for several hundred years, created by nature taking into account:

climate of our country,
the endurance of trees that constantly grew in the same area,
the existence of a certain forest area that protects young trees from strong winds and other climatic influences.

In addition, there is no point in waiting for newly planted seedlings to grow. Technologies that ensure their landing are partially used. For example, new, young trees or seedlings are planted in an already mined area. Moreover, the species of these trees should already grow in this mixed forest.

Broad-leaved forests of Russia

Despite the fact that these forests are found in our country more often than mixed forests, the volume of their tracts is significantly reduced. A forest can be classified as a broad-leaved species only if it contains several varieties of trees with deciduous and wide leaf blades. For comparison, in mixed forests, in addition to deciduous trees, coniferous trees grow, with needles in place of leaves. Essentially, these needles replace leaves for trees.

For the formation of these forests, a moderate climate and good humidity are needed. Sudden changes in temperature and harsh winters broad-leaved forests are sometimes able to tolerate. However, for their full development they need a more “calm” climate.

That is, in order to go through one cycle of its life, first buds grow on a tree, then leaves, flowers appear, and only then fruits. The leaves fall in the autumn period of the year, allowing the tree to prepare for the winter period. Surprisingly, the leaves become fertilizer and additional insulation for the winter for the same species that once grew on them. When winter comes, all processes in the trees are suspended, they fall into a state similar to sleep.

If we consider mixed forests, then coniferous species are more active in winter, as they are able to withstand even the harshest climatic conditions. Therefore, mixed forests combine different types of trees.

Broad-leaved forest types are present mainly in the south of Chile, America and a number of other countries, the climatic zones of which are similar in their weather conditions and temperature conditions.

The soils here are rich in useful minerals and fertilizers. Often, deciduous forests contain chernozems and podzolic soils. But sometimes there are also gray, brown forest and other varieties that are most characteristic of deciduous trees.

Leaves, as mentioned above, are complementary and almost universal nutrient for trees. They contain all the substances necessary for these breeds, allowing them to accelerate their growth or slow it down if climatic conditions have changed.

Winter in deciduous forests is quite mild; there are no sharp changes in the climatic picture of the natural zone. If we compare them with mixed trees, the climate of which varies depending on the natural zone, then deciduous tree species love climatically moderate winters and warm summers. Only in summer periods year, the tree can regain its strength after winter sleep and grow fully.

Due to such a temperate climate and the absence of strong humidity, the level of swampiness in these places is reduced. Therefore, you will hardly find swamps here. But they occur in those natural zones whose climate is closer to mixed forests and taiga areas, where the humidity is much higher.

The most common are forests, the main trees in which are linden, hornbeam or oak. But you can also find maple.

Our country is rich in a variety of forest species, while America has only a few tree species. In the past, this country was proud of its oak and chestnut forests. They have practically disappeared from our planet and are present in small clusters of trees.

In this regard, Russia has more opportunities to create the formation of various forests. It all depends on:

nature,
human activity,
the speed of development of urban infrastructure, which is the main reason for the deforestation of most forests in Russia.

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Mixed and broad-leaved forests | Geography 6th grade

Mixed forests– a natural zone of the temperate zone, transitional from the taiga zone to the deciduous forest zone. Mixed forests are formed in conditions quite humid climate, common in oceanic and transitional climatic areas continents in Europe, North America, South America, New Zealand, Tasmania.

This zone of mixed forests is characterized by a climate with moderately cold, snowy winters (January t° from –5 to –14 °C) and warm summers (July t° to +20 °C). The amount of precipitation (400-800 mm per year) is not much greater than evaporation.
The forests are coniferous-broad-leaved, and in more continental areas - coniferous-small-leaved, mainly on soddy-podzolic soils. The predominant coniferous species are: spruce, pine, fir; Small-leaved species include: birch, aspen; from broad-leaved trees: oak, maple, linden, ash. An increase in the share of broad-leaved species in the species composition occurs in the direction away from the poles and with an increase in climate humidity.
The fauna consists of both taiga species and species living in deciduous forests: hare, lynx, elk, fox, squirrel, wild boar, wood grouse, black grouse, etc.

The territory of the mixed forest zone is one of the most economically developed. There is a high population density here, located large number large cities. This led to the fact that the natural vegetation of the zone was preserved only to a small extent. large areas, and most of the territory is occupied by cities, agricultural lands, etc.

Broadleaf forests– a natural zone of the temperate zone, formed in the humid climate of the oceanic territories of the continents. The main areas of broad-leaved forests are distributed in Europe and North America, where they are sometimes distinguished as the southern part of a single zone of temperate forests; small areas of deciduous forests exist in South America.
This zone is characterized by a maritime and temperate continental climate with moderately cold winters (average January temperature from –5 to –15 °C) and fairly long warm summers (average July temperature up to +22 °C). The amount of precipitation (600-1500 mm per year) is approximately equal to or slightly greater than evaporation.

The vegetation is dominated by trees with broad leaves that fall off in the winter. Dominant species: oak, beech, maple, ash, linden, hornbeam, chestnut and other trees that provide significant shading; thick grass cover is typical. Under broad-leaved forests, brown forest and gray forest soils are common.
In Europe, broadleaf forests occupied the largest area. The most common tree here is oak (pedunculate, sessile and other types). In North America, broadleaf forests are prominent southeast of the Great Lakes. In South America, the zone is represented by southern beech forests in southern Chile.
Among the inhabitants of the zone there are ungulates and predators; among mammals, the characteristic species are mink, black ferret, European wild cat, dormouse, bison, etc. Birds include green woodpecker, cuckoo, woodcock, pheasant.

Favorable climate and soil fertility led to active settlement and development of this natural zone, expansion of arable land and deforestation, so the place of natural vegetation in most of the broad-leaved forests was taken by anthropogenic complexes.

Mixed forests, together with taiga and deciduous forests, make up forest zone. The forest stand of a mixed forest is formed by trees of various species. Within the temperate zone, several types of mixed forests are distinguished: coniferous-deciduous forest; secondary small-leaved forest with an admixture of conifers or broadleaf trees and a mixed forest consisting of evergreen and deciduous tree species. In the subtropics, mainly laurel-leaved and coniferous trees grow in mixed forests.

In Eurasia, the zone of coniferous-deciduous forests is widespread south of the zone taiga Quite wide in the west, it gradually narrows towards the east. Small areas of mixed forests are found in Kamchatka and the south of the Far East. In North America, such forests occupy vast areas in the eastern part of the temperate climate zone, in the Great Lakes region. In the Southern Hemisphere, mixed forests grow in New Zealand and Tasmania. The mixed forest zone is characterized by a climate with cold, snowy winters and warm summer. Winter temperatures in areas of the marine temperate climate are positive, and as they move away from the oceans they drop to -10 °C. The amount of precipitation (400-1000 mm per year) is not much greater than evaporation.

Coniferous-broad-leaved (and in continental regions - coniferous-small-leaved) forests grow mainly on gray forest and soddy-podzolic soils. The humus horizon of soddy-podzolic soils, located between the forest litter (3-5 cm) and the podzolic horizon, is about 20 cm. The forest floor of mixed forests consists of many grasses. Dying and rotting, they constantly increase the humus horizon.

Mixed forests are distinguished by a clearly visible layering, that is, a change in the composition of vegetation along the height. The upper tree layer is occupied by tall pines and spruces, and below grow oaks, lindens, maples, birches, and elms. Under the shrub layer formed by raspberries, viburnum, rose hips, and hawthorn, shrubs, herbs, mosses and lichens grow.

Coniferous-small-leaved forests, consisting of birch, aspen, and alder, are intermediate forests in the process of coniferous forest formation.

Within the mixed forest zone, there are also treeless spaces. Elevated treeless plains with fertile gray forest soils are called opoles. They are found in the south of the taiga and in the zones of mixed and deciduous forests of the East European Plain.

Polesie - low treeless plains, composed of sandy deposits of melted glacial waters, are common in eastern Poland, in Polesie, in the Meshchera Lowland and are often swampy.

In the south of the Russian Far East, where seasonal winds - monsoons - dominate within the temperate climate zone, mixed and broad-leaved forests, called the Ussuri taiga, grow on brown forest soils. They are characterized by a more complex layered structure and a huge variety of plant and animal species.

In the mixed forests of North America, white and red pine are often found among coniferous trees, and birch, sugar maple, American ash, linden, beech, and elm among deciduous trees.

The territory of this natural zone has long been developed by humans and is quite densely populated. Agricultural lands, towns, and cities are spread over large areas. A significant part of the forests has been cut down, so the composition of the forest in many places has changed, and the proportion of small-leaved trees in it has increased.