Tundra herbaceous plants list. Plants, animals and birds of the tundra zone. Elk and reindeer

Tundra is a natural zone of the subarctic belt, located between the ice zone in the north and the forest-tundra in the south. It is characterized by excessive moisture with a lack of heat, treelessness, extensive development of moss and lichen cover, and the presence of undersized shrubs and shrubs. The term "tundra" is borrowed from the language of the Sami, who live on the Kola Peninsula and call the treeless peaks of the mountains tundra. The tundra of Russia stretches in a wide strip along the northern borders.

Tundra in Russia occupies the Arctic islands Kolguev, Vaigach, the southern island of Novaya Zemlya and the continental coast of the Arctic Ocean from the Kola Peninsula in the west to Kamchatka in the east.

The average July temperature here is + 10-14 ° С. Annual precipitation is 300-400 mm. There is much more precipitation than can evaporate, so the forest-tundra is one of the most swampy natural zones. Melted snow water predominates in the rivers' feeding, so the rivers are flooded in the summer when the snows melt. The rivers of the forest-tundra have a warming effect on the climatic conditions in the valleys, therefore, along the river valleys, woody vegetation penetrates far into the tundra. In addition, river valleys protect forests from the fierce winds that occur there. The islets of forests are composed of birch, spruce, larch. The trees are undersized, in places bent to the ground. In the interfluves, there are low-growing sparse forests with a lichen cover. They alternate with shrub tundra. Influence of permafrost on the species composition of vegetation

In the warm season, in the tundra zone, the soil thaws only to a depth of no more than 50 centimeters. Next comes the permafrost layer. This factor is one of the decisive factors in the dispersal of plants in the tundra zone. The same factor affects their species diversity.

Permafrost has a significant impact on the terrain. Freezing and thawing of rocks leads to their deformation. As a result of the heaving process, surface forms such as bumps appear. Their height is no more than two meters above sea level, but the appearance of such forms also affects the vegetation of the tundra, its settlement over a certain territory.

The flora of the forest-tundra

The swamps of the forest-tundra are rich in peat, medicinal mosses, herbs, berries, the species composition of animals is quite diverse here.

In the tundra, only the uppermost soil layer and the lowest air layer adjacent to the earth's surface are most favorable for plant life. The one and the other layer is measured by only a few centimeters. It is not surprising, therefore, that many tundra plants are very stunted, they are spread out on the ground, and their root systems grow mainly in a horizontal direction and hardly go into depth. In the tundra, there are many plants with leaves collected in a basal rosette, creeping shrubs. All these plants, due to their short stature, make the best use of the heat of the surface layer of the air and protect themselves from excessive evaporation caused by strong winds.

Mosses and lichens play a very important role in the vegetation cover of the tundra. There are many types of them here, and they often form a continuous carpet over huge spaces. Most of the mosses and lichens found in the tundra These are, for example, many green mosses (pleurotium, chylocomium, cuckoo flax) (lichens from the cladonia genus (this includes deer moss and other related and similar species). However, there are also specific tundra species mosses and lichens.

Both mosses and lichens do well in the harsh conditions of the tundra. These low-growing, unpretentious plants can 'hibernate under the protection of even a thin snow cover, and sometimes even without it.

The bulk of flowering plants in the tundra are shrubs, shrubs and perennial grasses. Shrubs differ from shrubs only in 'smaller size - they are almost the same in height as small grasses. On flat areas of the tundra, where the snow cover is shallow, both shrubs and shrubs are low, they do not rise above the snow. Among these plants we find some dwarf willow species (for example, herbaceous willow), wild rosemary, blueberry, crowberry, dwarf birch. It often happens that shrubs are located in the thickness of a powerful moss-lichen cover, almost not rising above it. These plants seem to be looking for protection from mosses and lichens. Almost all herbaceous plants of the tundra are perennial. Perennial herbaceous plants of the tundra are distinguished by their short stature. Among them there are some grasses (fescue fescue, alpine meadow grass, arctic bluegrass, alpine foxtail, etc.) and sedges (for example, hard sedge). There are also a few legumes (astragalus umbellate, unclear penny, dirty ostrich). A characteristic feature of the tundra herb is large, brightly colored flowers. Their color is the most varied - white, yellow, crimson, orange, blue, etc. When the tundra blooms, it looks like a motley colorful carpet. The tundra usually blooms immediately, suddenly - after the first warm days come. And many plants bloom at the same time.

Plants and animals of the tundra and forest-tundra are well adapted to the harsh conditions. The forest-tundra is covered with sparse island forests, the basis of which is Siberian spruce, larch, and birch. A characteristic feature of this zone is the presence of a large amount of sphagnum peat bog, tundra-permafrost bog and gley-podzolic soils. Soddy-meadow soils, which cover variegated meadows in summer, have become widespread among the river armholes. Here you can find buttercup, light, valerian, berry. In both summer and autumn, the meadows are an excellent pasture for deer, as well as a wonderful habitat for birds and animals.

There are many reasons why the forest in the north gravitates towards river valleys. First of all, these are favorable microclimatic conditions of the valleys, better drainage, deep bedding of permafrost, sandy composition of alluvium.

Interesting features of the flora of the tundra Most months of the year, this area looks dull. Rare, stunted plants are either hidden under the snow, or bent to the ground by strong cold winds. But when spring comes, everything changes. For a short time, the dull terrain turns into a motley colorful carpet.

Arctic moss

This plant is most often found in the tundra zone. It grows on the surface of the soil, but prefers water bodies more. The plant is interesting in that it does not have a root system, but attaches to the soil with the help of rhizoids - long, thin threads. This species is rich in nutrients and grows all year round. Therefore, it serves as one of the main food sources for many animals and birds during their migration. Arctic moss is of particular interest to scientists, as it can be used to trace the natural evolution of life in a harsh climate.

Bearberry ordinary

it is called a bear berry, although in fact it is not bears who really like to eat it, but birds. Red dense berries, small green leaves attract the feathered inhabitants of the tundra. Bearberry bushes are undersized, located almost at the very surface of the soil. And the berries themselves can be on them all year round, hiding under the snow in winter.

Cloudberry

Cloudberry is a perennial herb. Interestingly, she is a close relative of raspberries, they belong to the same genus. However, unlike raspberries, cloudberries are not a shrub, and the berries of both are similar only in appearance, but their color is different.

Ledum

A short, beautifully flowering shrub with small leaves slightly curved at the edges. The stem and leaves of the wild rosemary are covered with peculiar hairs, which helps it keep warm in the harsh climate of the tundra. It is unusual that the bush is not eaten by animals, since parts of the plant smell quite harshly, and besides, they are poisonous

Diamond leaf

This plant belongs to the willow family. However, it has significant differences from its relatives. The diamond leaf resembles a dwarf willow that grows almost close to the ground. Like wild rosemary, its trunk, stems, roots are covered with hairs that retain heat. But unlike him, the diamond leaf is not poisonous, people and animals eat it. The plant is rich in vitamins and calcium, which makes it a reliable defense against scurvy.

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With the arrival of spring, when the first warm rays of the sun help the tundra to throw off its winter outfit for a short time, the area turns into a bright, colorful carpet. On the hillocks the first flowers of saxifrage, artichoke, ice siversia appear, sedge and cotton grass bloom in the swamps. Behind these first-borns of the polar spring, the Kamchatka rhododendron flourishes. The buds that have swollen since last year are in a hurry to turn into buds and bloom. Many plants gain strength throughout the summer, but as soon as flowers appear, the first snow sprinkles them, preventing the seeds from ripening. They will ripen only by next spring.

In autumn, strong mushrooms that do not know rot in these places appear - boletus mushrooms. Here they are called birch trees. They are often taller than the trees near which they grow.

In river valleys and on slopes sheltered from the wind, dwarf birches, polar willow, and northern alder grow, which can be easily confused with grass. Their height does not exceed 30 - 50 cm. The tundra is rich in lingonberries, blueberries and junipers. In winter, the shrubs are covered with snow, which protects them from frostbite.

Polar willow.

Those who believe that the tundra is lifeless are wrong. No, she is beautiful and cheerful in her own way.

Tundra: flora and fauna

The tundra zone stretches in the north of our country in a continuous strip from the Kola Peninsula to Chukotka. It occupies about 14% of the territory of Russia. The southern border of the tundra zone in the European part of the country (except for the Kola Peninsula) and in Western Siberia almost coincides with the Arctic Circle. In Eastern Siberia, it is sharply shifted to the north, and in the extreme east of the country, on the contrary, it descends far to the south, reaching the coast of the Sea of ​​Okhotsk.

The living conditions of plants in the tundra are rather harsh. Winter lasts 7 - 8 months, and summers are short and cool. The average temperature of the warmest summer month (July) usually does not exceed + 10 ° С. The life of plants is very short - only 3-4 months. Even at the very height of summer, in July, there are frosts and snow on some days. Sudden returns of frost find plants at the moment when they are in a state of active growth and full bloom.

There is little rainfall in the tundra, usually no more than 250 mm per year. However, in cold climates, this relatively small amount is more than enough. Much more water comes from the atmosphere than can evaporate from the earth's surface. Tundra soils are supplied with water in abundance. The bulk of precipitation falls in the summer; very little falls in winter (about 10% of the annual amount). Heavy showers do not happen, the rains usually only drizzle. There are especially many rainy days in autumn.

The snow cover in the tundra is very shallow, usually no more than 15-30 cm on level ground. It barely covers undersized bushes and shrubs. Strong winds blow off snow entirely from hills and rises, exposing the soil. The surface of the snow is constantly in motion under the influence of the wind. The mass of the smallest ice crystals that make up the snow moves at high speed in the horizontal direction, exerting a strong mechanical effect on everything that is located above the snow cover. This powerful stream of solid ice particles can not only destroy or damage plant shoots protruding above the snow - it even polishes rocks. The mechanical effect of snow driven by strong winds, the so-called snow corrosion, does not allow tundra plants to grow any tall. The stream of ice crystals cuts them, as it were. Only in deep depressions, which are filled to the brim with snow in winter, can you find relatively tall shrubs (they are human-sized).

The wind speed in the tundra can reach 40 m / s. Such a wind is so strong that it knocks a person down. In winter, the wind acts on plants mainly mechanically (through corrosion). But in summer, it has a predominantly physiological effect, increasing evaporation from the aboveground plant organs.

Permafrost is widespread almost throughout the tundra zone. The soil thaws in summer to a shallow depth - no more than 1.5-2m, and often much less. Below is the constantly frozen pound. Permafrost has a huge impact on tundra vegetation. This influence is mostly negative. The close occurrence of cold, ice-bound soil limits the growth of plant roots inward and forces them to settle only in a thin surface layer of the soil. Permafrost serves as a water seal, preventing moisture from seeping down, and causes waterlogging of the territory. Tundra soils usually have well-pronounced signs of swampiness: a peaty layer on the surface, underneath a bluish gley horizon. The temperature of the soil in the tundra in summer drops rapidly with depth, and this also adversely affects plant life. The surface of the vegetation cover, even much to the north of the Arctic Circle, can heat up in summer to + 30 ° С and more, while the soil already at a depth of 10 cm is cold enough - no more than + 10 ° С. Thawing of tundra soils at the beginning of summer is slow, because the upper horizons are usually penetrated by ice layers that absorb a lot of heat. Consequently, tundra plants develop in summer under conditions of a very special light regime. The sun rises low, but for many days it shines around the clock. Thanks to round-the-clock lighting, plants manage to receive a lot of light even in a short growing season - not much less than in mid-latitudes. The intensity of light in the Far North is relatively high due to the high transparency of the atmosphere. Tundra plants are well adapted to a long day, they thrive under such a peculiar light regime. Short-day plants cannot develop normally in tundra conditions.

Thus, in the tundra, among the many unfavorable factors for plant life, one of the most important is the lack of heat. Summer here is too short and cold, the soil thaws to a shallow depth and does not warm up well. It is often quite cold in the air in summer, and only on the surface of the soil, when the sun is shining, is it relatively warm. Consequently, in the tundra, only the uppermost soil layer and the lowest air layer adjacent to the earth's surface are most favorable for plant life. The one and the other layer is measured by only a few centimeters. It is not surprising, therefore, that many tundra plants are very stunted, they are spread out on the ground, and their root systems grow mainly in a horizontal direction and hardly go into depth. In the tundra, there are many plants with leaves collected in a basal rosette, creeping shrubs and shrubs. All these plants, due to their short stature, make the best use of the heat of the surface layer of the air and protect themselves from excessive evaporation caused by strong winds.

Let's get acquainted in more detail with the flora of our tundra.

Typical tundra is a treeless area with low and not always continuous vegetation cover. It is based on mosses and lichens, against which dwarf flowering plants develop - shrubs, shrubs, grasses. There are no trees in the real tundra - the living conditions here are too harsh for them. During a short and cold summer, the protective layer of the integumentary tissue necessary for normal overwintering does not have time to fully form on young shoots (without such a layer, young branches die in winter from water loss). The conditions for overwintering trees in the tundra are extremely unfavorable: strong drying winds, snow corrosion, which systematically "cuts" young trees and prevents them from rising above the snow.

Another circumstance is also important - the low temperature of the tundra soil in summer, which does not allow the roots to compensate for the large losses of water by the aboveground part of the tree during evaporation (the so-called physiological dryness of tundra soils).

Only in the very south of the tundra zone, in more favorable climatic conditions, one can find individual trees. They grow against the background of characteristic tundra vegetation and stand quite far from each other, forming the so-called forest tundra.

Mosses and lichens play a very important role in the vegetation cover of the tundra.

There are many species of them here, and they often form a continuous carpet over vast areas. Most of the mosses and lichens found in the tundra are not associated with their distribution exclusively with the tundra zone. They can also be found in forests. Such, for example, are many green mosses (pleurotium, chylocomium, cuckoo flax) (lichens from the cladonia genus (this includes deer moss and other related and similar species). However, there are also specific tundra species of mosses and lichens.

Both mosses and lichens do well in the harsh conditions of the tundra. These low-growing, unpretentious plants can “winter under the protection of even a thin snow cover, and sometimes even without it. The soil layer as a source of water and nutrients for mosses and lichens is almost unnecessary - they get everything they need mainly from the atmosphere. roots, and only thin filamentous processes develop, the main purpose of which is to attach plants to the soil.Finally, mosses and lichens, due to their short stature, make the best use of the near-ground, warmest layer of air in summer.

The bulk of flowering plants in the tundra are shrubs, shrubs and perennial grasses. Shrubs differ from shrubs only in "smaller size - they are almost the same in height as small grasses. But nevertheless, their branches are lignified, covered outside with a thin layer of protective cork tissue and bear wintering buds. It is quite enough to draw a clear line between shrubs and shrubs. hard.

On flat areas of the tundra, where the snow cover is shallow, both shrubs and shrubs are low, they do not rise above the snow. Among these plants we find some dwarf willow species (for example, herbaceous willow), wild rosemary, blueberry, crowberry, dwarf birch. It often happens that shrubs and shrubs are located in the thickness of a powerful moss-lichen cover, almost not rising above it. These plants seem to be looking for protection from mosses and lichens (in the forest, the situation is completely different). Some of the shrubs and shrubs are evergreen (crowberry, lingonberry, wild rosemary), others shed their leaves for the winter (various willows, dwarf birch, blueberry, arctous, etc.).

Almost all herbaceous plants of the tundra are perennial.

Perennial herbaceous plants of the tundra are distinguished by their short stature. Among them there are some grasses (fescue fescue, alpine meadow grass, arctic bluegrass, alpine foxtail, etc.) and sedges (for example, hard sedge). There are also a few legumes (astragalus umbellate, unclear penny, dirty ostrich). However, most of the species belong to the so-called forbs - representatives of various families of dicotyledonous plants. From this group of plants, one can name the viviparous mountaineer, the Eder mytnik, the European and Asian swimsuits, the pink Rhodiola, the alpine basil, and the forest and white-flowered geraniums. A characteristic feature of the tundra herb is large, brightly colored flowers. Their color is the most varied - white, yellow, crimson, orange, blue, etc. When the tundra blooms, it looks like a motley colorful carpet. The tundra usually blooms immediately, suddenly - after the first warm days come. And many plants bloom at the same time.

Many representatives of the tundra flora have adaptations aimed at reducing evaporation in the summer. The leaves of tundra plants are often small, and therefore the evaporating surface is small. The undersides of the leaves, where the stomata are located, are often covered with dense pubescence, which prevents too much air movement around the stomata and, therefore, reduces water loss.

Let's take a closer look at some of the most important tundra plants.

Dwarf birch, or dwarf birch (Vegula papa). The dwarf birch bears little resemblance to our common, familiar birch, although both of these plants are close relatives (different species of the same genus). The height of a dwarf birch is small - rarely more than half a human height. And it does not grow as a tree, but as a branchy bush. Its branches rise slightly upward, and often even spread over the surface of the earth. In a word, the birch tree is really dwarf. Sometimes it is so small that its creeping shoots are almost entirely hidden in the thickness of the moss-lichen carpet, and only leaves are visible on the surface. I must say that the leaves of a dwarf birch are not at all the same as those of an ordinary birch. Their shape is rounded, and the width is often greater than the length. And they are relatively small in size - like small copper coins. Along the edge of the leaf, there are small semicircular protrusions one after the other (such an edge of the leaf is called crenate by botany). The leaves are dark green, glossy above, and paler, light green below. In autumn, the leaves are beautifully colored - they turn bright red. The thickets of dwarf birch trees at this time of the year are unusually colorful, they always surprise with their bright crimson.

Seeing for the first time a twig of a dwarf birch tree with leaves, few of us will say that it is a birch. Even if we notice earrings on a branch, it will also be difficult to determine what is in front of us is a birch. Like the plant itself, these catkins are dwarf, very short - their length is no more than a nail. And in shape, they are not at all the same as that of an ordinary birch - oval or elongated-ovoid. When ripe, the catkins crumble into separate parts - small three-lobed scales and tiny, nuts-fruits, equipped with a narrow filmy edge. In this respect, dwarf birch differs little from ordinary birch.

The dwarf birch is one of the most common tundra plants. It can be found in almost the entire tundra zone. It is especially abundant in the southern part of the tundra, where it often forms thickets. In summer, deer feed on its leaves. And the local population collects larger specimens of the plant for fuel.

In the North, dwarf birch is often called dwarf birch. This name comes from the Nenets word "era", which means "shrub".

Blueberries, or gonobel (Wasstsht and Hgtosht). This is the name of one of the low tundra shrubs (its height rarely exceeds 0.5 m). A distinctive feature of this plant is the bluish tint of the foliage. In shape and size, the leaves are almost the same as those of lingonberries, but relatively thin, delicate. They appear in the spring and fall off by the fall. Blueberries, unlike lingonberries, are deciduous shrubs.

Blueberry flowers are inconspicuous, dim, whitish, sometimes with a pink tint. They are no larger than a pea, their rim is almost spherical, resembling a very wide jug in shape. " The flowers are arranged on the branches so that the corolla opening is directed downward. There are 4-5 small teeth along the edge of the hole. The denticles represent the ends of the petals (throughout the rest of the length, the petals have grown together into one whole).

Blueberry fruits are bluish, rounded berries with a bluish bloom. They resemble blueberries, but are larger than them. The pulp of the fruit is not watery, as a result of which this plant is sometimes called crowberry.

Cloudberry (Rubus catatogenus) is the closest relative of the raspberry (another species of the same genus). However, it is not a shrub, but a perennial herb. Every spring, from a thin rhizome in the soil, a short, erect stem with several leaves and only one flower grows. By winter, the entire aerial part of the plant dies, and in the spring another shoot grows again. Cloudberries are very different from raspberries. Its stems are devoid of thorns, the leaves are rounded-angular (shallow 5-spatula). The flowers are much larger than those of raspberries, with five white petals pointing in different directions. Cloudberry is unlike raspberry in one more respect: it is a dioecious plant. Some of its specimens always bear only male, sterile flowers, others only female, from which fruits are subsequently formed. Interestingly, male flowers are larger than female flowers, they can be up to 3 cm in diameter.

The fruits of cloudberries are similar in structure to the fruits of raspberries: each of them consists of several small juicy fruits, fused together into one whole. A separate fruit is somewhat similar to a tiny cherry: the outside is the pulp, and the inside is a stone. Such a simple fruit of botany is called a drupe, and the entire complex fruit of a cloudberry is a complex drupe. Raspberries have exactly the same type of fruit.

However, in appearance, the cloudberry fruit bears little resemblance to the raspberry fruit. Its individual particles are much larger than those of raspberries, and the color of the fruit is completely different. At the beginning of ripening, the fruits are red, at full maturity they are orange, like waxy. Ripe cloudberry fruit tastes good and is highly prized by the locals, who harvest them in large quantities from the tundra. Fruits contain from 3 to 6% sugar, citric and malic acids. They are eaten mainly in steamed and soaked form, they are also used to make jam.

Lichen lichen, or deer moss (Claciocha ranglirena). This is one of our largest lichens, its height reaches 10-15 cm. A separate lichen plant resembles some kind of fancy tree in miniature - it has a thicker "trunk" rising from the ground, and thinner twisting "branches". And the trunk and branches towards the ends gradually become thinner and thinner. Their tips almost completely disappear - they are not thicker than a hair. If you put several of these plants on black paper next to it, you get a beautiful white lace.

Yagel is whitish in color. It is due to the fact that the bulk of the lichen is made up of the thinnest colorless tubules - fungal hyphae. But if we look under a microscope a cross-section of the main "stem" of reindeer lichen, we will see not only mushroom hyphae. A thin layer of tiny emerald-green balls - microscopic cells, algae - stands out near the surface of the "stem". Yagel, like other lichens, consists of fungal hyphae and algae cells.

When wet, reindeer lichen is soft and resilient. But after drying, it hardens and becomes very fragile, easily crumbles. The slightest touch is enough to break off pieces of the lichen. These tiny debris are easily carried by the wind and can give rise to new plants. It is with the help of such random fragments that reindeer lichen mainly reproduce.

Yagel, like other lichens, grows slowly. It increases in height by only a few millimeters per year, although its dimensions are quite large. Due to the slow growth of reindeer lichen, one and the same tundra pasture cannot be used for several years in a row, you have to move to new plots all the time. If reindeer in the tundra eat reindeer lichen, it takes quite a long time to restore the lichen cover (10-15 years).

Yagel is of great national economic importance. It is known to be one of the most important food plants for deer in the tundra. Interestingly, deer unmistakably find it by smell even in winter under a layer of snow.

Fauna of the tundra

The fauna in the tundra is very peculiar and differs in some features from the animals of the Far North. They are not picky about food. Animals have thick fur, and birds have fluffy plumage. Animals change color: in summer they are light brown to match the vegetation cover, and in winter they are white or light gray to match the color of snow.

Typical animals of the tundra are arctic fox, lemming, reindeer, ptarmigan, polar wolf and snowy owl.

Arctic fox hunts for pieds and polar partridges. It has very valuable fur. Reindeer are not afraid of frost and snowstorms. Wide hooves allow him to run without falling through the snow and shovel snow in search of food.

In summer, countless mosquitoes, midges, and gadflies appear in the tundra. There are so many of them that it is impossible to work in the tundra without mosquito nets, they bite, get into the eyes, nose, and mouth.

At this time, many birds come here for nesting: geese, swans, ducks, waders. Many of them feed on insects.

Sapsa Yana

The presentation "Flora and fauna of the tundra" acquaints students with the peculiarities of the fauna and flora of the tundra.

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Flora and Fauna of the Tundra

The tundra stretches in a wide strip for many kilometers along the entire coast of the Arctic Ocean. Snow lies here for more than half a year, and frosts drop below -50. Cold winds blow, and summers are short, cool, on the hottest days the soil thaws no more than 1 meter, so the icy desert is called permafrost. Animals living in the tundra are forced to adapt to such conditions.

Vegetation Typical tundra is a treeless area with low and not always continuous vegetation cover. It is based on mosses and lichens, against which dwarf flowering plants develop - shrubs, shrubs, grasses. The roots of grasses, the trunks of shrubs are hidden in the moss and lichen turf. The bulk of flowering plants in the tundra are shrubs, shrubs and perennial grasses. Shrubs differ from shrubs only in smaller sizes - they are almost the same in height as small grasses. But nevertheless, their branches are lignified, covered from the outside with a thin layer of protective cork tissue and bear wintering buds.

There are no trees in the real tundra - the living conditions here are too harsh for them. During the short and cold summer, the protective layer of the covering tissue necessary for normal overwintering does not have time to fully form on young shoots (without such a layer, young branches die in winter from water loss). Conditions for overwintering trees in the tundra are extremely unfavorable: strong drying winds, snow corrosion , which systematically "cuts" young trees and does not allow them to rise above the snow. Only in the very south of the tundra zone, in more favorable climatic conditions, one can find individual trees. They grow against the background of characteristic tundra vegetation and stand quite far from each other, forming the so-called forest tundra.

Mosses and lichens play a very important role in the vegetation cover of the tundra. There are many types of them here, and they often form a continuous carpet over huge spaces. Most of the mosses and lichens found in the tundra are not associated exclusively with the tundra zone in their distribution. They can also be found in forests. Such are, for example, many green mosses (pleurotium, chylocomium cuckoo flax), lichens from the cladonia genus (this includes deer moss and other related and similar species). However, there are also specific tundra species of mosses and lichens. Both mosses and lichens do well in the harsh conditions of the tundra. These low-growing, unpretentious plants can winter under the protection of even a thin snow cover, and sometimes even without it. The soil layer as a source of water and nutrients for mosses and lichens is almost not needed - they get everything they need mainly from the atmosphere. They do not have real roots, but only thin filamentous processes develop, the main purpose of which is to attach plants to the soil. Finally, mosses and lichens, due to their short stature, make the best use of the surface, warmest layer of air in summer.

A person who first entered the tundra is especially surprised by dwarf willows. Some of them are extremely small, have creeping shoots spread among the moss carpet, and very much resemble some small herbaceous plants. Only by looking closely, you notice that these "herbs" have real willow earrings, though very small and short. The leaves of dwarf willows are also unusually small, unusual for us. Almost all herbaceous plants of the tundra are perennial. There are very few annual grasses. This is explained by the fact that the tundra has too short and cold summers. In a few cool summer weeks, it is difficult to go through the full life cycle - from germination of a seed to the formation of new seeds. This requires a very fast pace of development in low temperature conditions.

Many representatives of the tundra flora have adaptations aimed at reducing evaporation in the summer. The leaves of tundra plants are often small, and therefore the evaporating surface is small. The underside of the leaves, where the stomata are located, is often covered with dense pubescence, which prevents too much air movement around the stomata and, therefore, reduces water loss. In some plants, the edges of the leaves curl downward and the leaf itself looks like an incompletely closed tube. The stomata located on the underside of such a sheet end up inside the tube, which also leads to a decrease in evaporation. Adaptations to reduce water loss are essential for tundra plants. In summer, the cold tundra soil greatly complicates the absorption of water by the roots of plants, while the above-ground organs located in the warm surface layer of the air have all the conditions for vigorous evaporation.

Animal world. The tundra soil thaws only 35-40 cm in summer, and permafrost is tens of meters lower. In the tundra, summers are short and cold, winters are long and harsh, with strong winds, and little snow falls. In winter, the polar night lasts for a long time, and in summer the sun does not set for almost two months. All this creates special conditions for animals living in the tundra.

Reindeer The wild reindeer is probably one of the most beautiful ungulates living in our country! This graceful, strong animal is admirable! It is impossible to imagine the life of the peoples of the North of Russia without a deer. A reindeer team on which the "Gems" group wanted to take their fans "into the snowy dawn"; the chum, in which the northern peoples live, is made of reindeer skins; deer meat is the main food in the north; and reindeer milk is the most nutritious and healthy milk in the world!

Arctic fox Arctic foxes are commercial fur-bearing animals, which are sometimes called polar foxes. They are slightly smaller in size than real foxes. Arctic foxes are distributed throughout the tundra: to the north - to the ocean coast and to the south - to the northern border of the forest. Arctic foxes come in two colors: white and blue (more precisely, dark). The white arctic fox becomes pure white only in winter, and by summer, cross-shaped dark stripes appear on its back and shoulder blades, for which it received the name "cross". The blue fox is completely dark both in winter and in summer. White hair contains air inside and creates good insulation in winter, keeping it warm, much like the air between two frames in houses prevents a living space from cooling. The dark hair of the blue fox does not have this advantage, but it does have a thicker undercoat. That is why, in the fur trade, blue foxes are valued higher not only because of the beauty of the fur, but also because of its density. This is especially true of blue foxes from the Commander Islands.

Birds The snowy owl lives permanently in the Tundra. Auk White Partridge lives in the Tundra all year round Pink gull Tundra swan Kulik

The vegetation of the tundra and forest-tundra, its forms, methods of plant reproduction, adaptability to survival largely depend on the features that characterize these zones.

Geographical position

The location of the tundra zone falls on the Earth. On the continent of Eurasia, it stretches along the entire coast of the seas of the Arctic Ocean for tens of thousands of kilometers. The northern coast of the mainland North America is also occupied by tundra. The length of the zone from north to south is on average about 500 kilometers. In addition, the tundra occupies some islands near Antarctica. In the mountains, where the altitudinal zonation is expressed, mountain tundras are formed. Taking into account all the territories where the zone is located, its total area on the planet was calculated. It is about 3 million km2.

Forest-tundra is a zone where tundra vegetation and taiga vegetation are located in small areas. Forest-tundra stretches from west to east south of the tundra on the continents of Eurasia and North America. The length of the strip from north to south ranges from 30 to 400 kilometers. On its southern borders, the forest-tundra passes into the forest zone.

Climatic conditions affecting plant growth

The climate of the tundra and forest-tundra zone is very harsh. Winter lasts 6 to 8 months a year. During all this time, there is a constant snow cover, the air temperature sometimes drops to 50 degrees below zero. The polar night lasts about two months. Strong cold winds and snow storms almost never subside.

Summer in the tundra is short and cool. Frosts and precipitation in the form of snow are possible. Despite the surface of the earth does not receive much heat, since the sun does not rise high above the horizon and sends scattered rays to the earth. To survive in such conditions, tundra vegetation must adapt.

Influence of permafrost on the species composition of vegetation

In the warm season, in the tundra zone, the soil thaws only to a depth of no more than 50 centimeters. Next comes the permafrost layer. This factor is one of the decisive factors in the dispersal of plants in the tundra zone. The same factor affects their species diversity.

Permafrost has a significant impact on the terrain. Freezing and thawing of rocks leads to their deformation. As a result of the heaving process, surface forms such as bumps appear. Their height is no more than two meters above sea level, but the appearance of such forms also affects the vegetation of the tundra, its settlement over a certain territory.

Influence of soil on species diversity of vegetation

In the tundra and forest-tundra zone, a high is noted. It is especially noticeable during the period of snow melting. Water cannot penetrate deeply due to the presence of permafrost. Its evaporation also does not have a high intensity due to the low air temperature. For these reasons, melt water and precipitation accumulate on the surface, forming large and small swamps.

High waterlogging, the presence of permafrost, the prevalence of low temperatures impede the course of chemical and biological processes in the soil. It contains little humus, iron oxide accumulates. Tundra-gley soils are suitable for the growth of only certain plant species. But the vegetation of the tundra also adapts to such living conditions. A person who has visited these parts during the flowering period of plants will have indelible impressions for many years - the flowering tundra is so beautiful and attractive!

In the forest-tundra, the natural fertile layer of land is also thinly paved. The soil is poor in nutrients, it is characterized by high acidity. When the land is cultivated, a large amount of mineral and organic fertilizers is introduced into the soil. On the cultivated areas of the forest-tundra, there are more diverse types of herbaceous vegetation, trees and shrubs.

Types

The vegetation of the tundra and forest-tundra largely depends on the type. Their landscapes only at first glance seem monotonous.

The hummocky and hilly tundra occupy the largest territories. Among the bogs, the plant turf forms hillocks and hummocks, on which many plant species take root. A special type of tundra is polygonal. Here you can observe in the form of large polygons, which are broken by depressions and frost cracks.

There are other approaches to the classification of such a natural zone as the tundra. What vegetation prevails in a certain area, this will be the type of tundra. For example, the moss-lichen tundra consists of areas covered with various types of mosses and lichens. There are also shrub tundras, where thickets of polar willow, dwarf pine, and bushy alder are common.

Plants

As mentioned earlier, the vegetation of the tundra and forest-tundra had to adapt to the harsh climatic conditions of the Earth's subarctic belt. Otherwise, her life and development would be impossible here.

The fitness of tundra and forest-tundra plants is expressed in the following. Most of the fauna are perennials. Annual plants with a short summer duration would not be able to complete their life cycle. Only a small proportion of plants reproduce by seed. The main way to prolong life is vegetative.

The short stature of the tundra plants allows them to hold out during strong winds. This is also facilitated by the creeping nature of the shoots and their ability to intertwine with each other, forming a kind of soft pillow. In winter, all parts of the plants are covered with snow. This saves them from severe frosts. Most tundra and forest-tundra plants have a waxy coating on their leaves, which promotes moderate evaporation of moisture from their surface.

The vegetation of the tundra, photographs of certain species of which are in the article, is represented by perennial frost-resistant plants dominating in lowlands and swamps, buttercup, cotton grass, dandelion, and poppy. Dwarf birch and bushy alder grow from the trees. These tree species in the forest-tundra can already reach heights of three or more meters. Among the shrubs, blueberries, cloudberries, blueberries, and lingonberries are widespread. On the hills, mosses and lichens take root, many of which are the main type of food for the animals living in these places.

Forest-tundra and taiga

The vegetation of the tundra and taiga is very different from each other. Forest-tundra is a transitional zone between them. On the territory of the forest-tundra, among the treeless space, you can find islets of thickets of spruce, birch, larch and other tree species.

The forest-tundra zone is unique, as on its territory there is tundra vegetation and taiga vegetation, which becomes more noticeable as we move to the south. Forest areas, consisting of individual species of trees and shrubs, create the most favorable conditions for the growth of herbaceous vegetation. Thanks to trees and shrubs, the wind speed decreases, more snow is retained, which covers the plants, saving them from freezing.

Study of the vegetation of the subarctic belt

The vegetation cover of the tundra and forest-tundra has not yet been fully studied. A systematic scientific description of the species growing here began only in the middle of the last century.

To continue this work, special expeditions are being created today. In the course of them, scientists are also trying to establish how the animals living in these zones affect the vegetation of the tundra and forest-tundra. They want to get answers to questions about whether the species diversity of plants is changing in areas protected from the presence of certain animal species, how long it takes to completely restore the destroyed vegetation cover. So far, scientists have not found answers to all questions regarding the natural balance in the subarctic belt of the planet.

Fauna protection

The nature of the tundra and forest-tundra is very vulnerable. The restoration of the soil layer, vegetation cover takes more than a dozen years, and in some cases even centuries.
Man has long understood that it is he who has a destructive effect on the nature of the tundra and forest-tundra. Trying to redeem their guilt, people have created a number of nature reserves, national parks, wildlife sanctuaries. They are located both in Russia and other countries of the world.