What grows in the tundra. Tundra plants. What plants are found in the tundra? Elk and reindeer
The main feature of the tundra is the treelessness of monotonous swampy lowlands in a harsh climate, high relative humidity, strong winds and permafrost. Plants in the tundra are pressed to the surface of the soil, forming densely intertwined shoots in the form of a pillow. A wide variety of life forms can be seen in plant communities.
Distinctive features of the tundra zone are the predominance of sparse moss-lichen cover, severe swampiness, widespread permafrost and a short growing season. The harsh climatic conditions of the tundra zone cause the impoverishment of the organic world. The vegetation includes only 200-300 species of flowering plants, about 800 species of mosses and lichens.
Tundra vegetation consists primarily of lichens and mosses; found angiosperms - low grasses (especially from the grass family), chicken grass, sedges, polar poppies, shrubs and dwarf shrubs (for example, some dwarf species of birch and willow, berry shrubs of princeling, blueberry, cloudberry).
Most of the tundra zone of the Northern Hemisphere is occupied by subarctic tundras (northern and southern), on its northern outskirts they are replaced by arctic tundras, where there are no thickets of shrubs, along with mosses, lichens and grasses, arctic-alpine shrubs play a large role.
In the Eastern European part of Russia and Western Siberia, the southern tundras are characterized by large-bush tundras, with a well-defined layer of dwarf birch with an admixture of willows. To the north, the layer of shrubs thins out, they become more squat and sedge, along with mosses, shrubs and semi-creeping shrubs, acquires a greater role in the vegetation cover, and there is an admixture of dryads. In Eastern Siberia, with an increase in continental climate, large-bush tundras are being replaced by small-bush tundras with a different type of birch. Chukotka and Alaska are dominated by hummocky tundras with cotton grass and sedge, with the participation of hypnum and sphagnum mosses and an admixture of low-growing shrubs, which become fewer in number to the north. The subarctic tundras of Canada and Greenland are dominated by tundras dominated by ericoid shrubs. Tundras serve as pastures for deer, hunting grounds, and places for collecting berries (cloudberries, blueberries, shiksha).
The rather poor fauna of the tundra developed during the glaciation period, which determines its relative youth and the presence of endemics, as well as species associated with the sea (birds living in bird colonies; polar bears, pinniped rookeries). Tundra animals have adapted to harsh living conditions. Many of them leave the tundra for the winter; some (for example, lemmings) stay awake under the snow, others hibernate. Arctic fox, ermine, and weasel are widespread; there is a wolf and a fox; of rodents - voles.
Reindeer is a symbol of the tundra. This is the only representative of ungulates capable of existing in the open northern tundra and on the islands of the Arctic Ocean. Both males and females have large horns. It feeds mainly on lichens (moss moss), grass, buds and shoots of shrubs. In winter, it takes out food from under the snow, breaking it with its hooves.
Reindeer is widespread in Europe, Asia and North America; inhabits polar islands, tundra, lowland and mountain taiga. Herd polygamous animal. Reindeer make seasonal migrations, moving during the winter months to places rich in reindeer pastures, sometimes located many hundreds of kilometers from summer habitats (from the tundra to the forest-tundra and northern part of the taiga).
People domesticated reindeer about 2 thousand years ago. And now they breed it for meat and skins. In many parts of its range today, wild reindeer have been replaced by the domestic form of the species.
Typical inhabitants of the Russian tundra are reindeer, foxes and arctic foxes, bighorn sheep, wolves, lemmings and brown hares.
Due to the large amount of water in the tundra, various waterfowl willingly spend the summer - geese, ducks, loons, which fly south with the onset of winter. Characteristic features of the tundra fauna are extreme poverty associated with the severity of living conditions and the relative youth of the fauna, as well as homogeneity, determined by the circumpolar distribution of most species, and the connection of many inhabitants with the sea (birds living in bird colonies, polar bears, a number of pinnipeds). In general, there are not many birds: Lapland plantain, white-winged plover, red-breasted pipit, plover, snow bunting, snowy owl and ptarmigan.
Due to the cold summer, there are practically no reptiles in the tundra: low temperatures limit the ability of cold-blooded animals to live.
Among the amphibians, some frogs come from the south.
Rivers and lakes are rich in fish (nelma, whitefish, omul, vendace and others). Salmonids predominate; Dalliya lives in Chukotka and Alaska.
The predominant insects are Diptera. Mosquitoes and other blood-sucking insects are abundant. The swampiness of the tundra allows the development of a large number of blood-sucking insects that are active in the summer.
Relatively numerous: Hymenoptera (especially sawflies, as well as bumblebees, associated in their distribution with leguminous plants), beetles, springtails, butterflies. Permafrost and the associated swampiness are not conducive to the existence of hibernating forms and earthmovers.
With the arrival of spring, when the first warm rays of the sun help the tundra to shed its winter attire for a short time, the area turns into a bright colorful carpet. The first flowers of saxifrage, saxifrage, and ice siversia appear on the hills; sedge and cotton grass bloom in the swamps. Behind these firstborns of the polar spring, Kamchatka rhododendron blooms magnificently. The buds, swollen since last year, are in a hurry to turn into buds and bloom. Many plants spend the whole summer gaining strength, but as soon as the flowers appear, the first snow covers them, preventing the seeds from ripening. They will ripen only by next spring.
In the fall, strong mushrooms appear that do not rot in these places - boletus mushrooms. Here they are called birch caps. They are often taller than the trees they grow near.
In river valleys and on slopes sheltered from the wind, dwarf birches, polar willow, and northern alder grow, which are easily confused with grass. Their height does not exceed 30–50 cm. The tundra is rich in lingonberries, blueberries and junipers. In winter, 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 extends in the north of our country in a continuous strip from the Kola Peninsula to Chukotka. It occupies about 14% of Russia's territory. 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 pushed 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 quite harsh. Winter lasts 7 - 8 months, and summer is short and cool. The average temperature of the warmest summer month (July) usually does not exceed + 10 °C. The life span of plants is very short - only 3-4 months. Even at the height of summer, in July, there are frosts and snow on some days. Sudden returns of frost catch plants at a time when they are in a state of active growth and full flowering.
There is little precipitation 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 provided with abundant water. The bulk of precipitation occurs in the summer; in winter there is very little precipitation (about 10% of the annual amount). There are no heavy downpours; it usually just drizzles. There are especially many rainy days in autumn.
The snow cover in the tundra is very shallow - on level ground it is usually no more than 15-30 cm. It barely covers low-growing bushes and shrubs. Strong winds completely blow away the snow from hillocks and elevations, exposing the soil. The surface of the snow is constantly in motion under the influence of the wind. The mass of tiny ice crystals that make up the snow moves at high speed in the horizontal direction, exerting a strong mechanical effect on everything 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 grinds 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 flow of ice crystals seems to trim them. Only in deep depressions, which in winter are filled to the brim with snow, can relatively tall shrubs be found (they can be as tall as a person).
Wind speed in the tundra can reach 40 m/sec. This wind is so strong that it knocks a person off his feet. In winter, the wind affects plants mainly mechanically (through corrosion). But in summer it has a predominantly physiological effect, increasing evaporation from the aboveground organs of plants.
Permafrost is widespread throughout almost the entire territory of the tundra zone. The soil thaws in summer to a shallow depth - no more than 1.5-2 m, and often much less. Below is a permanently frozen pound. Permafrost has a huge impact on tundra vegetation. This influence is mostly negative. The close proximity of cold, ice-bound soil limits the deep growth of plant roots and forces them to be located only in a thin surface layer of soil. Permafrost serves as an aquifer, preventing moisture from seeping down and causing waterlogging in the area. Tundra soils usually have well-defined signs of swampiness: a peaty layer on the surface, underneath a bluish gley horizon. The soil temperature in the tundra in the summer drops rapidly with depth, and this also adversely affects plant life. The surface of the vegetation cover, even well north of the Arctic Circle, can heat up in summer to + 30 °C or more, while the soil already at a depth of 10 cm is quite cold - no more than +10 °C. Thawing of tundra soils at the beginning of summer is slow, because the upper horizons are usually penetrated by layers of ice that absorb a lot of heat. Therefore, tundra plants develop in the summer under conditions of a very special light regime. The sun does not rise high, but for many days it shines around the clock. Thanks to round-the-clock lighting, plants manage to receive quite a lot of light even during a short growing season - not much less than in mid-latitudes. The light intensity in the Far North is relatively high due to the high transparency of the atmosphere. Tundra plants are well adapted to long days; they develop well under this unique light regime. Short-day plants cannot develop normally in tundra conditions.
Thus, in the tundra, among many factors unfavorable for plant life, one of the most important is lack of heat. Summer here is too short and cold, the soil thaws to a shallow depth and does not warm up well. The air in summer is also often quite cold, and only on the surface of the soil, when the sun is shining, is it relatively warm. Consequently, in the tundra only the top layer of soil and the bottom layer of air adjacent to the earth’s surface are most favorable for plant life. Both layers measure only a few centimeters. It is not surprising, therefore, that many tundra plants are very short, they are spread out on the ground, and their root systems grow mainly in the horizontal direction and almost do not go deep. 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 ground layer of air and protect themselves from excessive evaporation caused by strong winds.
Let's get acquainted in more detail with the flora of our tundras.
A typical tundra is a treeless space with low and not always continuous vegetation cover. It is based on mosses and lichens, against which low-growing flowering plants - shrubs, dwarf shrubs, and herbs - develop. 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 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 loss of water). 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.
Another important circumstance is the low temperature of the tundra soil in summer, which does not allow the roots to replenish large losses of water from the above-ground 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, can individual trees be found. 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 vast areas. Most mosses and lichens found in the tundra are not associated in their distribution exclusively with the tundra zone. They can also be found in forests. These are, for example, many green mosses (pleurocium, chylocomium, cuckoo flax) (lichens of the genus Cladonia (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 tolerate the harsh conditions of the tundra. These low-growing, unpretentious plants can overwinter under the protection of even a thin snow cover, and sometimes without it at all. The soil layer as a source of water and nutrients is almost not needed for mosses and lichens - they get everything they need mainly from the atmosphere. They do not have real roots, and only thin thread-like 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 ground-level, warmest layer of air in the summer.
The bulk of flowering plants in the tundra are shrubs, dwarf shrubs and perennial herbs. Shrubs differ from shrubs only in their smaller size - they are almost the same in height as small herbs. But nevertheless, their branches become lignified, covered on the outside with a thin layer of protective cork tissue and bear wintering buds. It is enough to draw a clear line between shrubs and shrubs difficult.
On flat areas of the tundra, where the snow cover is shallow, both shrubs and shrubs are low and do not rise above the snow. Among these plants we find some dwarf species of willows (for example, grass willow), wild rosemary, blueberry, crowberry, and dwarf birch. It often happens that shrubs and shrubs are located in the thickness of a thick moss-lichen cover, almost without rising above it. These plants seem to seek 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, arcticus, etc.).
Almost all herbaceous plants of the tundra are perennial.
Perennial herbaceous plants of the tundra are characterized by short stature. Among them there are some grasses (squat fescue, alpine meadow grass, arctic bluegrass, alpine foxtail, etc.) and sedges (for example, hard sedge). There are also a few legumes (astragalus umbelliferum, common pennyweed, and common oleaginus). However, most species belong to the so-called forbs - representatives of various families of dicotyledonous plants. From this group of plants we can name the viviparous knotweed, the Eder's grass, the European and Asian swimworts, rosea rhodiola, alpine cornflower, woodland and white-flowered geraniums. A characteristic feature of tundra herbs is large, brightly colored flowers. Their colors are very diverse - 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 arrive. 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 underside of leaves, where the stomata are located, is often covered with dense pubescence, which prevents too much air movement near 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 (Vegina papa). The dwarf birch bears little resemblance to our ordinary, 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 person's height. And it grows not as a tree, but as a branchy bush. Its branches rise slightly upward, and often even spread across the surface of the ground. In short, the birch tree is truly 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. It must be said that the leaves of a dwarf birch are not at all the same as those of an ordinary birch. Their shape is round, 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 projections one after another (botanists call this edge of the leaf crenate). The leaves are dark green, glossy above, and paler, light green below. In autumn, the leaves become beautifully colored - they turn bright red. Thickets of dwarf birch are unusually colorful at this time of year; they always surprise with their bright crimson color.
Seeing a dwarf birch branch with leaves for the first time, few of us would say that it is a birch. Even if we notice earrings on a branch, it will also be difficult to determine that in front of us is a birch tree. Like the plant itself, these earrings are dwarf, very short - their length is no more than a fingernail. And their shape is not at all the same as that of an ordinary birch - oval or elongated-ovoid. When ripe, the earrings crumble into separate parts - small three-lobed scales and tiny, nut-like fruits, equipped with a narrow membranous edge. In this respect, the dwarf birch differs little from the ordinary birch.
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”.
Blueberry, or gonobobel (Uasstsht iN§tosht). 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. The shape and size of the leaves are almost the same as those of lingonberries, but relatively thin and delicate. They appear in the spring and fall off by autumn. 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 corolla is almost spherical, shaped like a very wide jug.” The flowers are located on the branches so that the corolla opening is directed downwards. There are 4-5 small teeth along the edge of the hole. The denticles represent the ends of the petals (along the rest of the length the petals are fused into one whole).
Blueberry fruits are bluish, round berries with a bluish bloom. They resemble blueberries, but are larger. The pulp of the fruit is not watery, as a result of which this plant is sometimes called crowberry.
Cloudberry (Kubus cataetoris) is the closest relative of raspberry (another species of the same genus). However, this is not a shrub, but a perennial herbaceous plant. Every spring, a short, erect stem with several leaves and only one flower grows from a thin rhizome in the soil. By winter, the entire above-ground part of the plant dies, and in the spring another shoot grows again. Cloudberries are different from raspberries in many ways. Its stems are devoid of thorns, the leaves are rounded-angular (shallowly 5-lobed). The flowers are much larger than raspberries, with five white petals pointing in different directions. Cloudberries are unlike raspberries in one more respect: they are dioecious plants. Some of its specimens always bear only male, sterile flowers, others - only female ones, from which fruits are subsequently formed. Interestingly, male flowers are larger than female ones; they can be up to 3 cm in diameter.
Cloudberry fruits are similar in structure to raspberry fruits: each of them consists of several small juicy fruits fused together into one whole. An individual fruit is somewhat similar to a tiny cherry: there is pulp on the outside and a pit on the inside. Botanists call such a simple fruit a drupe, and the entire complex cloudberry fruit 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; when fully ripe, they are orange, like wax. Ripe cloudberry fruits have a pleasant taste and are highly valued by local residents, who collect them in large quantities in the tundra. The fruits contain from 3 to 6% sugar, citric and malic acids. They are eaten mainly steamed and soaked; they are also used to make jam.
Lichen moss, or reindeer moss (C1ac1osha gangireppa). This is one of our largest lichens, its height reaches 10-15 cm. An individual moss plant resembles some kind of fancy tree in miniature - it has a thicker “trunk” rising from the ground, and thinner winding “branches”. Both the trunk and branches gradually become thinner and thinner towards the ends. Their ends almost completely disappear - they are no thicker than a hair. If you put several of these plants next to each other on black paper, you get a beautiful white lace.
Resin moss has a whitish color. It is due to the fact that the bulk of the lichen consists of the thinnest colorless tubes - fungal hyphae. But if we look at a cross-section of the main “stem” of moss under a microscope, we will see not only fungal hyphae. Near the surface of the “stem” there is a thin layer of tiny emerald green balls - microscopic cells, algae. Resin moss, like other lichens, consists of fungal hyphae and algae cells.
When wet, moss is soft and elastic. But after drying, it hardens and becomes very brittle and crumbles easily. The slightest touch is enough for pieces to break off from the lichen. These tiny fragments are easily transported by the wind and can give rise to new plants. It is with the help of such random fragments that moss mainly reproduces.
Resin moss, like other lichens, grows slowly. It grows in height only a few millimeters per year, although its size is quite large. Due to the slow growth of moss, the same tundra pasture cannot be used for several years in a row; it is necessary to constantly move to new areas. If deer in the tundra eat moss, it takes quite a long time (10-15 years) to restore the lichen cover.
Reindeer moss is of great economic importance. It is known to serve as 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 unique 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 color of the vegetation, and in winter they are white or light gray to match the color of snow.
Typical animals of the tundra are the arctic fox, lemming, reindeer, ptarmigan, polar wolf and snowy owl.
The Arctic fox hunts pieds and polar partridges. He has very valuable fur. Reindeer are not afraid of frosts and snowstorms. Wide hooves allow him to run through the snow without falling through and rake the snow in search of food.
In summer, countless mosquitoes, midges, and gadflies appear in the tundra. There are so many of them that you can’t work in the tundra without mosquito nets; they bite and get into your eyes, nose, and mouth.
At this time, many birds fly here to nest: geese, swans, ducks, waders. Many of them feed on insects.
The extremely harsh living conditions in the tundra are extremely unfavorable for plants. The amount of solar heat here is two times less than in a temperate climate. The time during which plant development is possible is very short - 2-3 months. Winter lasts about 8 months, the average annual temperature in the tundra is below zero everywhere. Frosts are possible in all months of summer. However, climatic conditions in the tundra are heterogeneous. In the USSR, the western part of the tundra zone is most favorable for plants - on the Kola Peninsula. The proximity of the Atlantic Ocean and the warm North Atlantic Current moderate the cold breath of the Arctic here. The average temperature in January is -6°, and precipitation falls up to 400 mm per year.
To the east, the climate becomes harsher: the temperature drops, the amount of precipitation decreases, and the summer becomes shorter. In many regions of the Yakut Autonomous Soviet Socialist Republic, the average January temperature is -40°. The annual precipitation in the north of Siberia is 200-300 mm, and at the mouth of the river. Lena is reduced to 100 mm. There is little snow in the tundra. In the west, the thickness of the snow cover is 50 cm, and in the east, in Yakutia, it is only 25 cm.
Very strong winds constantly blow in the tundra. In winter there is often a snowstorm and wind speeds reach 30-40 m per second. The blizzard lasts for 5-6 days. Winds blow snow from the hills into ravines and river valleys, and the bare ground freezes heavily. The frost-bound soil does not thaw completely during the short summer, and frozen soil - permafrost - remains at a certain depth from year to year (for more information on this, see article ""). In the far west of the tundra zone there is no permafrost. The further to the east, the wider the strip of permafrost soils. In Eastern Siberia, its southern border descends south of Irkutsk.
The soil in the tundra is always cold. Even in summer, at shallow depths, the temperature does not rise above +10°. Permafrost slows down soil formation. Water accumulates in the upper layers of the soil, supported by the permafrost layer, and this entails waterlogging of the surface and the accumulation of semi-decomposed plant remains - peat. But there are no thick deposits of peat in the tundra - the growth of plant mass here is too small (see article "").
Permafrost, low precipitation, low temperatures and strong winds create a unique water regime in the tundra. The roots of plants, despite the excess moisture in the soil, are not able to supply it to the above-ground parts of the plants in the required quantity. Therefore, plants in the tundra (for more details, see page 92), as in the desert, suffer from a lack of moisture. Naturally, the vegetation of the tundra, developing in such extremely unfavorable conditions, acquired a unique appearance.
In the middle zone of the tundra zone, large spaces are occupied by moss or lichen tundra. Their landscape is gray and monotonous. Their most characteristic feature is the absence of woody vegetation. Of the mosses, green mosses predominate. Peat mosses are less common; they usually do not form continuous carpets here. Lichens are represented by a huge number of species. Among them, the most common are bushy ones - cladonia, cetraria, alectoria. Along with mosses and lichens, small amounts of shrubs grow here: crowberry, arctic bearberry, etc. Their underground organs and buds are hidden in the moss cover and in winter they find good protection there from unfavorable conditions. A moss carpet, like a loose sponge, absorbs moisture and further contributes to waterlogging of the tundra.
The more southern regions of the tundra zone are characterized by shrub tundras. These are quite tall thickets of bushes. They consist of several tiers. In the first, upper tier there are mainly dwarf birch trees. In the second tier, various willows are widespread: arctic, herbaceous, reticulated, as well as crowberry, heather shrubs - wild rosemary, phyllodoceum. The third tier (ground cover) is formed by various mosses and lichens, but they are much less developed than in moss and lichen tundras. In river valleys and along the edges of swamps, larger (up to a meter or more) willows grow: woolly, Lapland, etc.
In the northern regions of the tundra, conditions are more severe and in winter even mosses and lichens freeze there. The vegetation in these areas of the tundra does not form continuous carpets. There is a lot of completely bare soil here. Among the numerous patches of bare soil, miserable vegetation huddles in the depressions - oppressed mosses, lichens and some small shrubs. This type of tundra is called spotted tundra.
In some places of the tundra, rocky soils come to the surface. Individual plants or small groups of them grow in islands on them. Most often found here are dryad, or partridge grass, polar poppies with red, yellow, white flowers, phyllodoce, arctic bearberry, and cassiope. This is rocky tundra.
The absence of trees and tall shrubs in the tundra is explained by a combination of unfavorable conditions. Drying strong winds are especially destructive for them in spring, when the above-ground parts of plants are strongly heated by the sun, and the roots cannot supply them with enough water from the cold soil. As a result, the above-ground parts of plants quickly lose water and die.
Insufficient snow cover also has a detrimental effect on plants. All parts of plants that rise above the snow cover in the tundra die off due to winter drying.
Individual trees, sometimes collected in small groups, groves, are found only in the extreme south of the tundra zone - in the forest-tundra. Forest-tundra is characterized by alternation of forest areas with tundra (mainly shrub tundra).
Various trees grow on the border of the forest. From west to east, birch, Norway spruce, Siberian spruce, Siberian larch and Dahurian larch replace each other. The trees on the forest border have a depressed appearance, they are no higher than 6 m. Trees are also found in the tundra, but along river valleys. Here they find protection from the wind. In addition, rivers flowing from south to north have warmer water, and this increases the temperature of the slopes surrounding the river. In addition, rivers drain the soil. The soil along the rivers warms up well, and usually there is no permafrost layer.
In the tundra zone there are many swamps, meadows and overgrown reservoirs. The swamps are covered with green mosses and various grasses: sedges, angustifolia cotton grass, and watchwort. Among them grow various berries: cloudberries, mamura, or clearings, small-fruited cranberries, and blueberries.
In the more southern regions of the tundra zone, hummocky peatlands are found. The depressions between the hillocks are overgrown with sphagnum mosses, and the hillocks are overgrown with lichens and mosses (cuckoo flax, peat and sphagnum mosses). Dwarf birch, crowberry, andromeda, blueberry and other shrubs are also found here.
Many plants in the tundra cannot go through all phases of their development in a short summer. Often they do not have time to form mature seeds. There are almost no annual plants in the tundra, and their number sharply decreases to the north. Between 71-74° N. w. annuals make up no more than one percent of the entire flora of flowering plants, and north of 74° they are represented by only one species - koenigia.
Thus, almost all tundra plants are perennial.
Captured by frost during flowering or fruit set, they interrupt development.
They continue to bloom or form seeds in the spring.
Some perennials have lost the ability to bear mature seeds in the tundra and reproduce only vegetatively.
Thus, on the Spitsbergen Islands, crowberry, dwarf birch, and fescue grass do not produce seeds. Bulbous and tuberous plants are rare in the tundra. Their development is hampered by severe soil freezing.
The tundra is dominated by evergreen plants with leathery leaves. They have various adaptations that reduce evaporation and make it possible not to spend a lot of time in the spring on the formation of new leaves. Evergreen shrubs from the heather family are widespread in the tundra: wild rosemary, andromeda, phyllodoce, cassiope, and also crowberry.
The harsh living conditions of plants explain their insignificant increase in organic mass. Lichens grow only 1-3 mm per year. In the polar willow on the Kola Peninsula, the shoots lengthen by only 1-5 mm per year and produce 2-3 leaves.
Tundra plants have developed peculiar forms that help them make best use of the sun's heat and protect themselves from the wind. The so-called trellis forms of shrubs and trees are especially characteristic. They are formed, for example, by birch, spruce, and various willows. The trunks and branches of these plants, except for individual twigs, are hidden under moss or lichen.
Many tundra plants take on a cushion-like shape. Numerous shoots extend from the root collar of such plants in different directions, which in turn branch repeatedly. The entire plant takes the shape of a hemisphere or pillow. A dense cushion is better warmed by the sun's rays, and the shoots are well protected from the drying effects of the wind. The dying lower leaves fall down, rot and enrich the soil under the pillow with humus. Pillows are formed, for example, by stemless gum and saxifrage.
Plants in the tundra generally “hug to the ground.” Thanks to this, they are less exposed to the drying effects of the wind and receive more heat, since the soil here warms up more than the air.
Many tundra plants have very large flowers. Thus, the inflorescences of the Arctic chamomile, whose height is 10-25 cm, reach 8 cm in diameter.
The flowers of many tundra plants are brightly colored (sweetwort, bluewort, myrtle, poppies) and are clearly visible from afar. This is very important for plants, since there are few pollinating insects in the tundra.
All plants of the tundra, located at high latitudes, are long-day plants. In summer they are constantly illuminated by the sun. Prolonged illumination compensates for the lack of heat in the tundra; This explains the faster development of tundra plants. Most tundra plants manage to bloom and produce seeds, despite the short summer.
The flora of the tundra zone is young in comparison with other zones. It was formed in the mountainous regions of Northeast Asia and the Far East during the Tertiary and Ice Ages. At this time, the territory of the modern tundra was covered with a glacier. Then, following the retreating glacier, this new flora moved along the coast of the Arctic Ocean and along the mountain ranges of the Altai, Sayan, Ural, and Caucasus to the west, to territories freed from ice.
It also penetrated into the mountainous regions of Europe (Carpathians, Alps). This explains the similarity between the tundra (Arctic) flora and the high-mountain (Alpine) flora. Through the Bering Strait, this flora spread eastward to North America.
The flora of the tundra zone is very poor. In the tundras of Eurasia and North America there are no more than 500 species of higher plants.
The tundra contains many diverse plant communities. Their distribution is closely related to soil, topography and other conditions. These communities change from north to south in line with climate change.
The flora of the tundra natural zone is not rich. First of all, this is due to harsh climatic conditions. Tundra landscapes can be swampy, peaty and rocky. There is no fertile soil ideal for plant development here. Various types of moss grow in swampy areas. Among the mosses there are entire fields of lingonberries, cloudberries and blueberries. By autumn, many fruits ripen in these berry fields. Plants similar to moss grow on the peat and rocky soils of the tundra. One of these is moss. This plant covers vast areas of the tundra. There is so much reindeer moss that whole herds of wild deer feed on it all year round.
Not only mosses and reindeer moss are found in the tundra. Here, in places well protected from strong winds, in the valleys of rivers or lakes, you can find large meadows where a variety of grasses reach a height of half a meter.
The tundra is also characterized by a complete absence of forests. The only trees found are polar willow and dwarf birch. These trees are more similar to shrubs. The dwarf birch is so small that its thin, curved trunk practically lies and hides in moss or reindeer moss. Only small branches with miniature leaves are raised upward. The polar willow is even smaller than the birch. During snowfalls, all its branches are covered with snow.
Animals of the tundra
The most numerous inhabitants of the tundra belong to the class of birds. Especially in summer, a large number of geese, ducks and. In lakes and rivers they look for food, mainly insects, plants and small fish. There are so many birds in the tundra that some of its reservoirs are either white with geese or black with ducks. The screams and cackling of birds can be heard everywhere.
In summer, the tundra is infested with midges and mosquitoes. They rush through the air like clouds, attack animals and people, and give them no rest either night or day. To get rid of annoying insects, people light fires or dress in special suits.
During severe winters, most birds fly to the southern regions. It is not uncommon for numerous herds of reindeer to pass through here. With the help of their hooves, they dig moss out of the ground. Sometimes you can see arctic foxes, musk oxen, lemmings and stoats here. Occasionally a polar owl is seen in the tundra. It is white in color, and therefore the partridges and pieds that it hunts simply do not notice it against the background of the snow.
Most of the animals of the tundra are covered with thick plumage or fur. Their winter color, as a rule, turns white, which helps them hide from enemies or sneak closer to their prey.