The climate is moderate continental; Atlantic-continental region with moderate continental intra-annual distribution types. precipitation. Summers are warm and humid, winters are mild.
Average January temperatures vary from west to east from -4.5 to -8 °C,
July - from +17 to +19 °C. On average, 600-680 mm of precipitation falls per year.
21. Features of the formation of soil and vegetation cover of mixed and broad-leaved forests.
The diversity and complexity of the relief, climate and soils of Ukraine explains the richness of the species composition of the country's flora. The vegetation cover is poorer in river floodplains and swamps. Thus, about 270 species grow in the swamps of Ukrainian Polesie, many of which are also found in forests, meadows and reservoirs. And on the saline soils of the country there are about 200 plant species, of which 70 species are typical halophytes.
22. Zonal types and subtypes of soils in mixed and deciduous forests
and their characteristics.
IN In Polesie, zonal soddy-podzolic soils are common on ancient alluvial fluvio-glacial deposits, and zonal gray forest soils are common on loess-like loams. Soddy-podzolic soils They are common in watershed areas and are divided into three subtypes: soddy-slightly podzolic, soddy-medium podzolic and soddy-podzolic-gley soils. Gray forest soils. Three subtypes of grays are common forest soils: light gray, gray and dark gray. They form under broad-leaved forests on carbonate loess and loess-like rocks. Typical profile gray forest soils are represented by humus-eluvial horizon gray with a thickness of 32-35 cm, under which lies a thick alluvial horizon, reaching a depth of 90-100 cm. It exhibits strong compaction and a nutty-prismatic structure. In the upper part of the horizon there is an abundant dusting of silica. Effervescence begins at a depth of 120-140 cm.
23. Intrazonal soils of mixed and broad-leaved forests and their characteristics.
Swampy soils Ukraine is quite diverse. The predominant type is lowland swamps, but transitional and even raised swamps are also found. The thickness of lowland peatlands is small and amounts to 1-4 m, rarely 8-10 m. The ash content of their upper horizons most often fluctuates between 20-25%, often reaching even 65-7% (in floodplains). The acidity of the vast majority of peat soils is very low. The degree of saturation of peat with bases is always high, and, as a rule, exceeds 90-92%. Lower peat bogs contain a lot of mobile forms of nitrogen and phosphorus. The latter, in addition, often forms powerful accumulations of vivianite at a depth of 70-80 cm. They are poor in mobile potassium.
24. Fauna of mixed and deciduous forests.
Forest zone represented in Ukraine by lowland forests of Polesie and mountain forests of the Carpathians and Crimea. Despite the significant differences in living conditions in these three areas, they also have a number of common features. The abundance of shelters in the forest allows many relatively large animals to remain secretive. Lifestyle, which often determines the possibilities of their prosperous existence. In forests, animals are distributed into tiers, which significantly increases species diversity animal population. The food reserves of forests are greater than those of other lands, and, most importantly, they are more stable. Especially great importance for the animal population they have significant winter reserves of food, which, in the conditions of relatively mild winters of Ukraine, ensure a safe wintering for a variety of mammals and birds. In particular, among forest birds The largest number of wintering forms is noted here. Polesie is characterized by such mammals as boar, elk, roe, river beaver), squirrel, common vole Very few here lynx, pine martens, but, nevertheless, they represent typical inhabitants of this zone. Of the birds, much more diverse and numerous than mammals, widespread black grouse, meet grouse And capercaillie although their ranges are significantly narrower. Extremely numerous in places viper ordinary), viviparous lizard .
South of the taiga zone in temperate continental and continental climate Mixed and broad-leaved forests are common. Unlike the tundra and taiga, which stretch from the western to the eastern borders of the country, this zone is not a continuous strip. Mixed forests occupy the central part of the East European Plain and the south Western Siberia. Broad-leaved forests are represented in the European part of Russia, as well as in the south of the Far East.
East, where they are called the “Ussuri taiga”.
Most of mixed and deciduous forests location
lies in a temperate continental climate, which is characterized by fairly warm and longer, compared to taiga, summers or less Cold winter. Average temperatures in July are + 16...+20 °C, and in January -8...-16 °C. The average annual precipitation (500-600 mm) slightly exceeds the evaporation value. In the south of the zone, in deciduous forests, summers are warmer and longer, therefore evaporation is higher, the humidification coefficient approaches 1. In general, the zone of mixed and deciduous forests is characterized by a milder climate compared to the taiga zone. The species composition of vegetation (both trees and grasses) is significantly richer than that of the taiga. There are both coniferous (spruce, pine) and broad-leaved (oak, linden, maple, etc.) tree species. At the same time, there are more coniferous species in the north of the zone, closer to the taiga, and broad-leaved species in the south, closer to the steppes. The distribution of trees is determined not only by climatic conditions, but
and mechanical composition of soils. Light sandy soils are most favorable for pine, heavy loam for spruce. Oak “prefers” carbonate soils. In place of cleared forests, secondary forests appear from small hardwood- birch and aspen. Unlike taiga, in mixed and especially broad-leaved forests, tiering is clearly visible. There are many shrubs (hazel, bird cherry, honeysuckle, elderberry, euonymus) and herbs
(lungwort, lily of the valley, hoofweed, bell, etc.).
Soil formation conditions, primarily climate and vegetation,
are not the same in the north and south of the zone, which leads to the formation of different
soil types. Soddy-podzolic forests are developed under mixed forests, and under
broad-leaved - gray forest soils. They differ in their
structure, thickness of the humus horizon, humus content, and therefore
and fertility. Highest natural fertility among forest soils
characteristic of gray forest soils.
Animal world. The diverse food supply determined the species richness
quality of the animal world. Among the ungulates here, in addition to the elk, you can meet
there are Noble deer, roe deer, wild boar and bison (in nature reserves). From the predator
kov - fox, wolf, Brown bear, black polecat, weasel, marten. In forests
many birds, especially songbirds. However, in winter their numbers and species composition
are significantly reduced.
Many species of animals in the zone of mixed and deciduous forests in
are on the verge of complete extinction, while the numbers of others are falling. In nature
natural form animal world zones have been preserved only in nature reserves.
Subzone mixed forests lies further south. Starting in the west
de the European part of the Union in a wide stripe, it is gradually
tapering, it reaches the Urals. In mixed forests along with pine
ny and small-leaved species broad-leaved trees grow -
linden, oak, maple, elm. Beautiful mixed forests! At different times
During the course of the year they become either bright green or golden yellow.
thy or crimson.
The mixed forest subzone has a milder climate and longer summers.
than in the taiga. Therefore, it is possible to grow here
quantitative tree species.
The number of broad-leaved species decreases to the east.
Beech and hornbeam are widespread in the southwest. To the east
35° east etc. on the East European Plain they no longer meet
Linden. Beyond the Urals, due to the continental climate, they disappear
the latter broadleaf trees; of the deciduous ones remain
cutting and aspen.
Broadleaf species are reappearing only in the south
Far East. Here, in humid summer conditions, the plant
ity is very rich, differing from European in its vi
ladies. Various maples, Mongolian oak, Amur linden grow
with bright yellow, larger than that of an ordinary linden,
flowers, Manchurian walnut, velvet tree, so called
for its light gray bark, velvety to the touch, black bere
for with dark brown birch bark; some trees produce beautiful,
valuable ornamental wood for various products.
The natural conditions of the forest zone are very favorable for life.
nor many animals. Here they are provided with abundant food,
especially seeds of coniferous trees obtained from ked cones
ra, pine, larch, spruce. Hunters often find themselves
eat pine nuts stored for the winter by taiga rodents
(squirrel, chipmunk) and some birds (nutcracker).
Many animals are adapted
got ready to climb the tree
tree llamas, such as lynx.
Like on the ground, they run around
revyam squirrel, chipmunk (Fig.
35), sable.
Besides them, there lives an elk, which chooses swampy areas in summer.
places and forested river banks, and in winter - dry watersheds. All over
In the taiga there are bears, foxes, and ferrets (Fig. 36). Very
there are many birds making nests in the trees. Animals and birds
living in the forest, have a protective color to match the color of the soil,
catching trees, fallen leaves, greenery.
In the forest zone, especially in the taiga, hunting and breeding are developed
in special fur-bearing farms.
Broad-leaved species are more demanding of heat and moisture than conifers. In summer the trees form great amount leaves with a large surface area that evaporate a lot of moisture. Therefore, an indispensable condition for the growth of broad-leaved forest is an abundance of precipitation in summer period. Broad-leaved forests are located in the west of the European part former USSR, wedging out towards the Urals, and on Far East in Primorsky Krai.
Broad-leaved forest is characterized by a complex layered structure of the tree stand. There are usually 3 tiers. In the forests of the European part of the former USSR, the first tier consists of large trees - oak, linden, maple, ash. Under their crowns grow trees of the second size - wild apple and pear trees, bird cherry, hawthorn. Below are large shrubs - buckthorn, euonymus, viburnum, etc. There are almost no mosses or lichens in the ground cover, since a thick layer of fallen leaves interferes with their development. They are replaced by a variety of perennial grasses, usually broad-leaved. Their above-ground part dies off during the winter, and underground they form rhizomes, tubers, and bulbs, which allows them to bloom quickly in early spring, until it is light in the forest and the foliage of the trees has not developed. Wind-pollinated trees and shrubs, such as oak, hazel, and alder, also bloom early, as long as the leaves do not interfere with the flight of pollen. Insect-pollinated plants bloom at different times.
Different parts of plants have medicinal value: in early spring they harvest bark from oak and viburnum, collect primrose and lungwort, in summer - linden and elderflower, hawthorn flowers, in autumn - elderberry and hawthorn fruits.
Almost all herbaceous plants, living in oak forests, are perennials. Their lifespan is often measured in several decades. Many of them reproduce poorly by seeds and maintain their existence mainly through vegetative propagation. Such plants, as a rule, have long above-ground or underground shoots that can quickly spread in different directions, capturing new territory.
The above-ground part of many representatives of oak groves dies off in the fall, and only the rhizomes and roots in the soil overwinter. They have special renewal buds, from which new shoots grow in the spring. However, among the species of oak groves there are also those in which the above-ground part remains green in winter. Plants of this kind include hoofweed, hairy sedge, and green grass.
IN coniferous forests Shrubs play an important role, especially blueberries and lingonberries. In a broad-leaved forest, on the contrary, there are usually no shrubs at all; they are completely unusual for our oak forests.
Among the herbaceous plants growing in Central Russian oak forests, the so-called oak forest ephemeroids are of particular interest. An example of them could be different kinds corydalis, goosebumps, buttercup anemone, spring guillemot. These small, relatively low-growing plants surprise us with their extraordinary “haste”. They are born immediately after the snow melts, and their sprouts sometimes make their way even through snow that has not yet had time to melt. snow cover. It is quite cool at this time of year, but the ephemeroids nevertheless develop very quickly. A week or two after birth, they already bloom, and after another two to three weeks, their fruits and seeds ripen. At the same time, the plants themselves turn yellow and lie down on the ground, and then their above-ground part dries out. All this happens at the very beginning of summer, when, it would seem, the conditions for the life of forest plants are the most favorable - enough heat and moisture. But ephemeroids have their own special “development schedule”, not the same as that of many other plants - they always live only in the spring, and by summer they completely disappear from vegetation cover. Early spring is most favorable for their development, since at this time of year, when the trees and shrubs have not yet put on leaves, it is very light in the forest. There is quite enough moisture in the soil during this period. A heat, such as in summer, ephemeroids do not need at all.
All ephemeroids are perennial plants. After their aboveground part dries out at the beginning of summer, they do not die. Living underground organs are preserved in the soil - some have tubers, others have bulbs, and others have more or less thick rhizomes. These organs serve as receptacles for reserve nutrients, mainly starch. It is precisely due to the previously stored “building material” that stems with leaves and flowers develop so quickly in the spring.
Ephemeroids are characteristic of our Central Russian oak forests. There are a total of up to ten species. Their flowers have a bright, beautiful color - lilac, blue, yellow. When there are a lot of such plants and they all bloom, you get a motley colorful carpet.
In addition to herbaceous plants, mosses are also found on the soil in oak forests. However, in this respect, oak forests are very different from taiga forests. In the taiga we often see a continuous green carpet of mosses on the soil. This never happens in oak forests.
Here the role of mosses is very modest - they are occasionally found in the form of small spots on piles of earth thrown out by a mole. It is noteworthy that in the oak forest there are common special types mosses are not at all the same ones that form a continuous green carpet in the taiga. Why is there no moss cover in the oak forest? One of the main reasons is that mosses are depressingly affected by leaf litter, which accumulates on the soil surface in a broad-leaved forest.
Broadleaf plants
Broad-leaved forest is characterized primarily by great variety tree species. This is especially noticeable when compared with coniferous forest, with taiga. There are much more tree species here than in the taiga - sometimes you can count up to a dozen of them. The reason for the species richness of trees is that broad-leaved forests develop in more favorable conditions. natural conditions than taiga. Tree species that are demanding on climate and soil can grow here and cannot tolerate the harsh conditions of taiga regions.
A good idea of the diversity of tree species in a broad-leaved forest can be obtained by visiting the famous forest area called the Tula Zaseki (it stretches like a ribbon from west to east in the southern part of the Tula region). In the oak forests of the Tula Zaseks there are such trees as pedunculate oak, small-leaved linden, two types of maple - Norway and field maple, common ash, elm, elm, wild apple tree, wild pear.
What is characteristic of a broad-leaved forest is that the various tree species included in its composition have different heights, forming, as it were, several groups in height. The most tall trees- oak and ash, lower ones - Norway maple, elm and linden, even lower ones - field maple, wild apple and pear. However, trees, as a rule, do not form clearly defined tiers well delimited from each other. Oak usually dominates, with other tree species most often playing the role of satellites.
The species composition of shrubs is also quite rich in the broad-leaved forest. In the Tula abatis, for example, there are hazel, two types of euonymus - warty and European, forest honeysuckle, brittle buckthorn, rose hips and some others.
Different types of shrubs vary greatly in height. Hazel bushes, for example, often reach a height of 5 - 6 m, and honeysuckle bushes are almost always shorter than human height.
Broad-leaved forests usually have well-developed grass cover. Many plants have more or less large, wide leaf blades. That's why they are called oak broadgrass. Some of the herbs found in oak forests always grow in single specimens, never forming dense thickets. Others, on the contrary, can almost completely cover the soil over a large area. Such massive, dominant plants in oak forests Central Russia The most common species are common sedge, hairy sedge and yellow green grass.
Broadleaf trees have broad, flat leaves—thickness that is much less than length and width—that typically fall once a year. This group includes maples, beeches, ash trees, eucalyptus trees, and various shrubs. In addition to classification according to the type of leaves, trees are divided according to the lifespan of the leaves - into deciduous and evergreen. Deciduous trees have a clear change in leaf cover: all the leaves on the tree lose their green color and fall off, for some time (in winter) the tree stands without leaves, then (in spring) new leaves grow from the buds. Evergreen trees do not have a clear change in leaf cover: foliage is on the tree at any time of the year, and the change of leaves occurs gradually, throughout the life of the tree.
In areas with long, cold winters, deciduous trees shed their leaves in the fall. In the tropics, where longitude daylight hours During the year it changes slightly; the leaves do not fall off in the winter.
Dropping leaves helps save energy because in winter sunlight too little for photosynthesis in leaves. In autumn, trees go into a dormant state. The movement of water and nutrients through the vessels inside the trees stops, as a result the leaves dry out and fall off. However, by this time the plant has already managed to accumulate enough nutrients to ensure bud break and the growth of new leaves in the spring. The green pigment chlorophyll is destroyed in the fall, and other pigments that give autumn leaves yellow, red and red colors.
Oak
Oak is the main forest-former of broad-leaved forests in Europe. In the European part of Russia, the English oak (Quergus robur) grows - one of our most durable and largest trees. However, in plantings, with the exception of parks, this plant is quite rare, although it has no equal in a number of properties. In particular, pedunculate oak has the highest recreational resistance and is extremely drought-resistant.
In private areas it is used in single plantings. It tolerates moderate pruning, so you can form very beautiful tapeworms with a spherical, obovate and even tent-shaped crown.
Elm
In the forests of the non-chernozem zone, two species from the elm family naturally grow: smooth elm (Ulmus laevis) and c. rough (U. scabra). This large trees, which are part of the dominant tier of broad-leaved and coniferous-deciduous forests. The use of these species for landscaping purposes last decades controlled by a widespread disease - Dutch elm disease.
Common ash
Ash reaches a height of 30-40 m.
Its trunk is straight. The bark is light gray, darkening with age. The crown is very loose, openwork, letting in a lot of light. Root system powerful, highly branched. Ash is very picky about soil, but tolerates salinity better than others. This is one of the main breeds of field-protective breeding, it is light-loving, in youth it is more shade-tolerant, thermophilic and does not tolerate spring frosts, it grows almost throughout the entire European part Russian Federation, often mixed with other species: oak, hornbeam, maple, sometimes forms pure or almost pure stands. Inflorescences are paniculate, dense.
The flowers of these trees are usually dioecious, less often bisexual, but sometimes there are dioecious trees.
Ash blossoms in May before the leaves bloom. Pollinated by wind.
The fruits are single-seeded lionfish, collected in clusters, ripen in October-November and fall in winter or early spring.
Forest beech (there is also eastern beech) is a tree up to 40 meters high and up to one and a half meters in diameter with light gray bark and elliptical leaves. Occupies large spaces in Western Europe, in our country it grows in the western regions of Ukraine, Belarus and the Kaliningrad region. Eastern beech is distributed in the Caucasus at an altitude of 1000-1500 meters above sea level, in Crimea - at a level of 700-1300 meters, forming a belt beech forests.
The main value of beech is its fruits - nuts, which ripen in September - October. They contain up to 28 percent fatty semi-drying oil, up to 30 percent nitrogenous substances, starch, sugars, malic and citric acids, tannins, up to 150 mg% of tocopherols and the poisonous alkaloid fagin, which decomposes when the nuts are fried, which as a result become harmless to humans . A coffee substitute is prepared from the nuts; ground nuts in the form of flour are added to regular flour when baking various bakery products. Beech wood is very valuable and decorative.
Maple
Various types of maples are widespread in deciduous forests. Most often found here is the Norway maple, or common maple - a tree up to 20 meters tall, with gray bark and five-lobed large dark green leaves. Distributed in the European part of the country, mainly in the western and central parts, and in the Caucasus. Its leaves and shoots can be used in medicinal purposes. It has been established that the leaves contain up to 268 mg% ascorbic acid, alkaloids and tannins. An infusion or decoction of the leaves has a diuretic, choleretic, antiseptic, anti-inflammatory, wound-healing, and analgesic effect. In folk herbal medicine it was used for kidney stones, jaundice, as an antiemetic and tonic. Crushed fresh leaves were applied to wounds to heal them.
Oak and beech, elm, maple and ash are very valuable species trees whose wood is considered to be of high quality building material, and the bark is used for household and medical needs.
Complex burs
I tier - pine (30-35m), birch, spruce;
II tier - linden, oak;
III tier - less pronounced - hazel, euonymus, honeysuckle;
IV tier - well defined - lichens, blueberries, wood sorrel...
There is no pine regeneration - complete shading:
pine deciduous forest.
Broad-leaved forest - forest-forming species: oak, linden, ash, maple, elm, hornbeam.
The tiered structure is well expressed, the number of tiers is 7-8 and there are a large number of root systems; Soddy-podzolic soils.
Broad-leaved forests involve much deeper soil layers in their biological cycle of substances, due to the location of the root system.
There is a lot of snow in the winter, melt water are well absorbed by the litter. The soil is moist, rich in minerals and organic substances. Light conditions change throughout the season.
Trees in oak forests are arranged in tiers.
I tier - oak (50m);
II tier - maple, linden, elm, ash;
III tier - wild apple tree;
IV tier - deciduous shrubs and undergrowth.
In early spring in the forest you can see a whole range of colors - yellow, blue, indigo, white.
These are early flowering plants: oak anemone, anemone, buttercup anemone, corydalis, spring guillemot, amazing violet, etc. Then
The trees are blooming, the last to bloom is the oak tree. At the end of May, shrubs begin to bloom, herbaceous plants begin to bloom: nomad, chickweed, lily of the valley, green grass, tenacious, warbler, raven's eye.
In summer, oak forests look the same; in autumn they transform again due to the changing color of the leaves of oak, ash, maple, and linden. Red berries of viburnum and the eyes of euonymus warty stand out against their background.
Birch forests. It is difficult to imagine our forests without birch with its white trunk and fluffy, spreading crown. The most common species is the warty birch (its branches are covered with yellow warts, the leaves are small and slightly pubescent). The breed is light-loving, undemanding to the soil, grows quickly and reaches a height of 30 meters by the age of forty.
Rowan and rose hips are constantly found in birch forests.
Raspberries grow in clearings.
appear in spring yellow flowers rams or primroses, swimsuits. In summer, forest geraniums, spreading and peach-leaved bellflowers, many grasses, and sedges bloom. Meadowsweet is found in damp places.
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 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 occupy not such a large proportion of the forest territory of the Russian Federation as coniferous taiga. 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 broken lines. Pure mixed forests are found south of the taiga, as well as beyond the Urals to the Amur region.
Climate
Mixed-type forest plantations are characterized by 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 sod-podzolic soil, and in the west - on brown forest. 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. High 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 local residents and 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.
Natural area mixed and deciduous forests occupy a smaller area than coniferous forests. However, this complex, formed under fairly warm and humid climate, is distinguished by a wide variety of flora and fauna.
Characteristics of the natural zone Mixed forests
Mixed forests are a transitional link between taiga zone And wide deciduous forests. The name of the natural area speaks for itself: both coniferous and deciduous trees grow here. Mixed forests are found in Russia and the European region, South and North America, New Zealand.
The climate of this natural complex quite soft. In winter, the temperature drops to -15 degrees Celsius, and in summer it ranges from +17-24.
Compared to the taiga, summers are warmer and longer. Number per annum atmospheric precipitation exceeds evaporation, which gave rise to the appearance of deciduous trees.
A distinctive feature of mixed forests is a well-developed grass cover growing on soddy-podzolic soils.
Rice. 1. In the mixed forest zone, grass cover is very developed.
This natural zone is characterized by a clearly defined layering - a change in the type of vegetation depending on the height:
- the highest tier of coniferous-deciduous trees forest areas made up of mighty oaks, pines and spruces;
- below are linden, birch, wild apple and pear trees;
- then the shortest trees grow: viburnum, rowan;
- Below are raspberry, hawthorn, and rose hip bushes;
- The layering of mixed forests is completed by a variety of grasses, mosses and lichens.
The fauna of mixed forests is also diverse. Large herbivores (elk, wild boar, deer and roe deer), rodents (beavers, mice, ferrets, squirrels), and predators (foxes, wolves, lynxes) live here.
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Rice. 2. Lynx is a typical representative of forest predators.
Description of the broad-leaved forest zone
As you move south of the continent, they change climatic conditions, which leads to the change of mixed forests to broad-leaved ones. As a result, there are significantly fewer coniferous trees, and dominance is completely transferred to deciduous species.
For broad-leaved forests it is quite typical warm climate with mild winters and long warm summer. The amount of annual precipitation slightly exceeds evaporation, due to which wetland soils - very rare for these territories.
Characteristic tree species for this zone are maple, linden, oak, beech, ash.
In dense thickets of deciduous forests, dense tree crowns do not allow the grass cover to fully develop. The ground in such areas is covered with a layer of fallen leaves. As it decomposes, it contributes to the formation of humus and the enrichment of gray and brown forest soils.
Rice. 3. In the zone of deciduous forests, coniferous trees are rare.
The fauna of deciduous forests is no different from the mixed forest zone. However, as a result active work human population, the number of wild animals has decreased significantly, and currently they live only in nature reserves or in remote areas.
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