"Tundra World around" - Tundra zone. Beasts. Adaptations to life. Fish. Animal World tundra. Deer. What is the beast master of the Arctic? The world. 4th grade. The soil surface is disturbed by the caterpillars of tractors and all-terrain vehicles, the plants die. Harsh winter (frost to -50 ° C) Cool short summer. White partridge. Musk ox Mining.
"Tundra lesson" - Find the island of New Earth. The symbol of Russia is Russian birch. Tundra. Flora of the tundra. Plan. Crossword. Animal World tundra. Ecological pyramid. Work with the card. Algae fish polar bear. Food chain.
"Plant Cultures" - Wheat, rye, carrots, barley. Pears - 5000. Apple, corn, cherry, pear. Field crops. Filaments are made of yarn, and weaving of yarn from yarn. - Divided into several main branches. Plants. Apple trees - more than 10,000 varieties. Do you know how many vegetables are in a bowl of soup? Wheat. Potatoes. Tomato, cabbage, onion, plum.
"Tundra and forest-tundra" - the valleys of the Pur and Taz rivers. Describe the SE of the tundra zone (2) and forest-tundra (3). What are the main types economic activity man in the tundra. What is the difference from the location of the zone arctic desert (one)? Lingonberry and moss. Voronika (black siksha, driftwood). Cotton grass. Describe the climatic conditions in the tundra and forest-tundra zones.
"Tundra Zone" - Flora. The main occupation of the local population is reindeer herding. Climate. The natural conditions of the tundra are less severe than in the zone of arctic deserts. Summer is very short. Thousands of kilometers from west to east is a cold treeless plain ... Ecological problems. The lesson of natural history in the 4th grade "Tundra".
"Tundra Geography" - The border of the tundra. Flora of the tundra. The average or typical tundra is predominantly moss. What is tundra. Tundra. Title. Creeping polar willows and dwarf birch trees hidden by mosses appear. Types of tundra: Arctic, typical, mountain. Tundra is located north of the taiga zone. Summer and autumn tundra is rich in mushrooms and berries.
Tundra is a country of permafrost, long winter gloom and short polar summer with a low, warming sun. Extremely harsh living conditions in the tundra are extremely unfavorable for plants. The amount of solar heat here is two times less than in temperate climates. The time during which the development of plants is possible is very short - 2-3 months. Winter lasts about 8 months, the average annual temperature is everywhere below zero. Frosts are possible in all months of summer. In the USSR, the western part is most beneficial for plants. tundra zone - Kola Peninsula. The proximity of the Atlantic Ocean and the warm North Atlantic Current moderate the cold breath of the Arctic in these places. The average January temperature here is -6 °, and precipitation falls to 400 mmin year.
To the east, the climate becomes more severe: the temperature decreases, the amount of precipitation decreases, and summer becomes shorter. In many areas of the Yakut ASSR average temperature January -40 °. Annual rainfall in the north of Siberia is 200–300. mm,and at the mouth of the river. Lena reduced to 100 mmThere is little snow in the tundra. In the west, the snow cover is 50 cm,and in the east, in Yakutia, only 25 cm.
In the tundra very strong winds are constantly blowing. In winter, there is often a blizzard and the wind speed reaches 30-40 mper second. Shooting clouds of snow, knocking people off their feet and turning sleds with deer, a blizzard rages on the boundless expanses of the tundra. Often it lasts for 5-6 days. Winds blow snow away from elevations into hollows, river valleys, and bare earth freezes over. Frost-bound soil does not thaw completely in a short summer, and at some depth the frozen soil — permafrost — persists from year to year (see t. 1 DE, Art. ""). The thickness of the frozen layer can reach several meters. At the extreme late-tade of the tundra zone, this layer no longer exists. The farther to the east, the wider the band of permafrost soils. In Eastern Siberia, its southern boundary descends south of Irkutsk.
The soil in the tundra is always cold. Even in summer, at a shallow depth, its temperature does not rise above + 10 °. Permafrost slows down soil formation. In the upper layers of the soil water is accumulated, supported by the permafrost layer, and this entails waterlogging of the surface and accumulation of the half-decomposed plant remains, peat. But there are no powerful halls of peat in the tundra - here the increase in plant mass is too small (see Art. "").
Permafrost, low precipitation, low temperature and strong wind create a unique and very harsh environment in the tundra. Evaporation, at least during some periods of the season, exceeds the possibility of water supply by roots. Therefore, plants in the tundra, as well as in dry areas, have xeromorphic features, i.e., are adapted to reduce evaporation. And small leaves, often folded, are covered with hair, have a wax coating, etc.
Recent studies have shown, however, that these traits are also a consequence of the adaptation of plants to the chemical characteristics of the soil. It was also established that when low temperatures the soil disrupts the synthetic activity of the roots, they are poorly assimilated nitrogen and phosphorus. As a result, plants grow poorly: their size decreases, they become small-leaved. Naturally, the vegetation of tundra, which develops in such extremely unfavorable conditions, acquired a peculiar appearance.
AT middle lane tundra zone large areas are occupied by moss and lichen tundra. Their landscape is gray and monotonous. The most characteristic of him is the complete absence of woody plants. Of the mosses, green mosses predominate. Peat mosses are less common and do not form usually solid carpets. Lichens are represented by a huge number of species. The most common among them are the bushy ones - cladonia, tsetrarii, alecties. Together with mosses and lichens here grow in a small amount of shrubs; crowberry, arctic nurse, etc. Their underground organs and buds are hidden in the moss cover, where in the winter they find good protection from adverse conditions. The moss carpet, like a loose sponge, absorbs moisture and contributes even more to the swamping of the tundra.
For the more southern areas of the tundra, shrub tundras are characteristic. It is quite tall in several tiers of overgrown shrubs. In the first, upper tier, the Karlika birch mainly grows, in the second - various willows are widespread: polar, grassy, reticulate, as well as crowberry, heather bushes - wild rosemary, philodloceum. The third tier (ground cover) is formed by various mosses and lichens, but they are much less developed than in the moss and lichen tundras. In the river valleys and along the outskirts of the lot, larger (up to a meter and higher) willows grow: woolly, Lapland and others.
In the northern regions of the tundra, conditions are more severe and in winter even mosses and leaks are frozen out. In these areas of the tundra, among numerous sites and patches of bare soil, miserable vegetation huddles — oppressed mosses, lichens, and some small scrub-niches. This tundra is called spot-resistant. Her vegetation uses every stone for protection, every unevenness of relief-fa for her settlement.
In some places of the tundra, rocky soils come to the surface. This is rocky tundra. Here islands grow individual plants or small groups of them. The most common dryad, or kuropato grass, polar maki-ki with red, yellow, white flowers, fillodots, arctic tokno-loknyanka, kassiopa.
The absence of trees and high ku-starni in the tundra is due primarily to the destructive strong drying winds for them in springtime, when the aerial parts of the plants are very hot by the sun and the roots cannot supply sufficient amount of water from the cold soil. Under these conditions, the aerial parts of plants quickly die.
A disastrous effect on plants and the insignificance of snow cover. All parts of plants that rise above the snow cover in the tundra dry out in the winter. Severe frosts and hurricane winds dehydrate tissues, and dense snow crystals in a blizzard rip off the bark and break down the buds. As a result, the branches die off.
Separate trees, sometimes gathered in non-large groups, groves, are found only in the extreme south of the tundra zone - in the forest-tundra. The forest tundra is characterized by alternation of forest areas with tundra (mainly with shrub tundra).
On the border of the forest grow various trees. From west to east, the birch across, the European spruce, the Siberian spruce, the Siberian larch and the Dahurian larch alternate. At trees on the border of the forest oppressed species, they are not higher than 6 mThere are trees in the tundra, but only along river valleys, forming peculiar green tongues among dull and monotonous treeless spaces. In the valleys they find protection from the wind. In addition, in the rivers flowing from south to north, the water is warmer, and this increases the temperature and the slopes surrounding the river. In addition, the rivers drain the soil. The soil along the rivers is well warmed, and the level of the permafrost layer is greatly reduced here.
In the tundra zone there are many marshes, meadows and: overgrown reservoirs. The swamps are covered with green mosses and various grasses: sedges, narrow-leaved cotton grass, wah-th. Among them are growing different berries: cloudberries, mammur, or snowberry, small-fruited cranberries, hubik.
In the more southern areas of the tundra zone, there are hilly peatlands. The depressions between the mounds overgrown with sphagnum mosses, and the hillocks - with lichens and mosses (Ku-Kushkin flax, peat and sphagnum mosses). There is also a dwarf birch, so-called ronika, andromeda, blueberries and other bushes.
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. In the tundra there are almost no annual plants, and to the north, even without that, a small number of them sharply decreases. Between 71-74 ° s. sh. one-year-olds 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 - kenigia.
Thus, almost all tundra plants are perennial. Captured by frost in flowering or when setting fruit, they interrupt development. Here is how one researcher describes the tundra at the time of the onset of harsh winter: “Many plants stand with frozen but alive leaves, with swollen flower buds, with half or almost ripe fruits. Being in full life, they were captured by a sudden freezing cold. ” In spring, tundra plants continue to bloom or form seeds.
Some perennials have lost the ability to bring mature seeds in the tundra and are multiplied only vegetatively. So, on the Spitz-Bergen Islands, they do not produce crow seeds, dwarf birch, and fescue grass. Bulbs and tuberous plants are rare in the tundra.
In the tundra, vech-green plants with leathery leaves dominate. They have various devices, which reduce evaporation and make it possible not to spend a lot of time in the spring to form new leaves.
The harsh living conditions of plants explain the negligible increase in their organic mass. Lichens grow by only 1-3 mmin year. In the polar willow on the Kola Peninsula, shoots lengthen by only 1–5 per year. mmand give 2-3 leaves.
The tundra plants developed peculiar forms that help them make the best use of the sun's heat and protect themselves from the wind.
The so-called spear forms of shrubs and trees are especially characteristic. They are formed, for example, birch, spruce, various willows. The trunks and branches of these plants, except for individual twigs, are hidden under moss or lichen.
Many tundra plants acquire a pillow shape. From the root of the neck of such plants in numerous directions, there are numerous sideways, which in turn are forked several times.
A dense cushion warms up better with the sun's rays, and on the run it is well protected from the drying action of the wind. Dying off the lower leaves fall down, rotten and enrich the soil with humus under the pillow. Pillows form, for example, the stemless samolev, kamnelomki. They are so dense that from afar
remind stones covered with moss. All the more surprising it is to see them in the flowering period, when they are covered with a multitude of pale pink and white flowers.
Plants in the tundra in general "cling to the ground." Due to this, they are less exposed to the drying effect of the wind and get more heat, since the soil here is heated more strongly than the air.
Many tundra plants have very large flowers. So, the inflorescences of arctic chamomile, whose height is 10-25 cm,reach 8 cm in diameter.
The flowers of many plants are brightly colored and well visible from a distance. This is very important for plants, as there are few insects in the tundra that produce pollination.
Lawns with bright green, juicy low-growing grass, covered in the first weeks of short summer by a colorful carpet of lush flowers: blue eyes of forget-me-nots and bitterness, yellow spots of buttercups, pink tassels of astragalus and red clusters of mytnik, are pleasing to the eye.
Many representatives of the tundra flora are pre-red ornamental plants and, undoubtedly, can decorate new cities and industrial centers being built on the far northern outskirts.
The flora of the tundra zone in comparison with other zones is young. It was formed in the mountain regions of Northeast Asia and the Far East during the tertiary and glacial periods. At this time, the territory of the modern tundra was covered by a glacier. Then, following the backslide-glacier, this new flora moved along the coast of the Arctic Ocean and along the mountain ranges of the Altai, the Sayans, the Urals, the Caucasus to the west, to ice-free territories. It penetrated into the mountainous regions of Europe (Kar-pata, Alps). This explains the similarity of tundra (arctic) flora and alpine (alpine) flora. Through the Bering Strait, this flora spread to the east, to North America.
The flora of the tundra zone is very poor. In the tundra of Eurasia and North America there are no more than 500 species of higher plants.
In the tundra, there are many diverse plant communities. Their distribution is closely related to the soil, topography and other conditions. These communities are changing in direction from north to south, according to climate change.
The tundra for the first time to visit a person seems to be dismal and inhospitable, but, having learned this country closer, he finds the modest nature of the tundra beautiful and considers her sheer vegetation to be of interest to her.
summary of other presentations “Natural zone of the Arctic deserts” - the Arctic Ocean space. The zone of arctic deserts. Polar bear. Different plants. Walrus. Kyre. Arctic. Land in the Arctic. Man and the Arctic. Loon Wildlife of the Arctic. Dead ends. Animal. The whole sky sparkles.
"Life in the Arctic" - How not to freeze. How not to die of hunger. How to make a fire. Snow inflatable. Franz Josef Land. Instructions for the survival of man in the Arctic. The kingdom of snow and ice. Marine life. Snow House Acquaintance with the Arctic deserts. Round-the-clock lighting. Vegetable world. Strong-willed qualities. The climate of the Arctic desert. Arctic. Wildlife of the Arctic. How to survive in the Arctic. Fish fauna. Natural wealth of the Arctic.
"Satellite communications in the Arctic" - The architecture of the Arctic communications and broadcasting system. Visibility conditions for geostationary satellites. Tasks of the Arctic satellite communications and broadcasting system. Consumers of communication services. The population of the Arctic. Telecommunication services in the arctic region. Minerals. Communication and broadcasting. Stable communication zone. Arctic shipping routes. The organization of satellite communications and broadcasting in the Arctic. Real consumers of services.
“Arctic Animals” - Sea Leopard. List of used material. Pinnipeds. In late autumn, the female polar bear digs a den in the snow. With the help of wings, penguins swim like fish feast using fins. The polar bear is the largest predator in the world. A polar bear usually weighs between 150 and 500 kilograms. As a rule, only one egg is laid by penguins. Walrus. The walrus has a massive, wrinkled body covered with rare bristles.
"Russian Arctic" - International cooperation. Arctic. Main national interests. Regulatory regulation in the Arctic. The economic structure of the Arctic zone. Speech Coordination activities. World reserves of hydrocarbons. Extreme climatic conditions. Russian hydrocarbon reserves. Programs affecting the development of the Arctic zone of the Russian Federation. Basic documents. Basic implementation mechanisms.
“Arctic deserts and tundras” - Forest Tundra Zone. Geographic dictation. Dwarf birch. Industrial waste. Mosses. Birds. Top representatives typical tundra. Sparse forests. Flora of the Arctic. Geographical position. Nenets. Animals Adaptation of animals to the conditions of the tundra. Tundra. Get acquainted with geographical location zones. In the summer there are many mosquitoes in the tundra. Wildlife of the Arctic. Shrub forest tundra.
MANAGEMENT OF EDUCATION BEKOVSKY DISTRICT
MUNICIPAL EDUCATIONAL INSTITUTION
SECONDARY SCHOOL №2 pp Bekovo
BEKOVSKY DISTRICT OF THE PENZA REGION
SCIENTIFIC - RESEARCH WORK ON THE TOPIC:
"The adaptability of plants to harsh environmental conditions (for example, tundra and forest-tundra vegetation)".
The work was performed by students of grade 6
Municipal educational institution of secondary school №2 р.п. Bekovo
Bekovsky district of the Penza region
Volchenkova Nadezhda and Samarin Andrey. Supervisor - biology teacher Chervyakova Tatyana Alexandrovna.
Bekovo
2006
1. Epigraph.
2. Tundra is not a “mistake of nature”, but a flower and berry garden.
3. Environmentally unfavorable factors.
4. Arsenal of adaptations to harsh environmental conditions:
a) pubescent crushed leaves;
b) the spherical shape of the bush;
c) height of shrubs and growth in the horizontal direction;
d) evergreen;
e) simultaneous disclosure of both vegetative and generative buds.
5. Lesotundra, as an independent landscape zone.
6. Features of the structure of trees growing in harsh conditions:
a) appearance;
b) root system;
c) the structure of the escape.
7. Lichens, their diversity and fitness.
Iii. Conclusions on the work.
Iv. Literature.
Introduction
We know that vegetable world Our planet is amazingly diverse, plants known more than 350 thousand species. Plants are found in icy Antarctica and high in the mountains, in the depths of the oceans, where the ray of light practically does not penetrate, and in waterless deserts. If conditions are favorable, plant communities differ in surprising diversity, but where conditions are unfavorable, there are only a few plants that have managed to adapt to them.
We had a unique opportunity to visit areas of tundra and forest-tundra, and to see first-hand the influence of environmental factors on the plants living there.
On the basis of the “expedition” accomplished, this work was compiled.
We formulated the purpose of our work as follows - to show what adaptations plants, growing in the tundra and forest-tundra, acquired in the process of evolution, to harsh environmental conditions.
Based on the goal, identified the following tasks:
Collect herbarium of flowering plants with the most pronounced features for these conditions;
Collect a collection of lichens and show their diversity;
Make photos of tundra and forest-tundra species;
To study the relevant literature on this topic;
Analyze the collected material and draw conclusions about the adaptability of plants to the harsh conditions of the tundra and forest tundra.
We consider the topic disclosed in our work to be relevant because, not only has our horizons been expanded, but material has also been collected and prepared, which will be used repeatedly in biology and geography lessons.
It seems to me that the tundra is not ending,
It is like the sea, but it does not swing,
She is like a sea - the sea is calm.
For hundreds of miles such wide.
Where, then, is such sadness
Relentlessly compressing the chest?
And only one desire - to look,
Watch the mist spread into the distance
Look to the pain in the nose
And to know that the tundra does not end,
It is like a sea - it just does not rock.
This northern outskirts of the country stretched along all our Arctic coasts from Murmansk to Chukotka and occupied almost 1/6 of its territory.
It became customary to consider the nature of this zone as severe and scanty. But experts on the tundra do not exaggerate when they say: it is abundant and beautiful, it is not a “mistake of nature”, not “fruitless backyards” of our land, and not only are the subsoil rich here, not dependent on cold weather. The plain tundra is a huge pasture, moreover, surprisingly for the North, year-round! In any season, deer eat their favorite lichen lichen. In winter, they extract it from under a thin snow canopy with their hooves; In summer, branch feed is also added to lichens - shrubs and bushes.
In the short months of summer, the tundra turns into a flower and berry garden. It is replete with bright corollas of petals, beads of lingonberries, cranberries, cloudberries, and bluish blueberries turn blue with lights.
Mosses and lichens cover it with solid carpets.
The tundra plants have adapted to the brevity of the growing season (only 2-2.5 months), to the proximity of permafrost and marshiness of the soil. Evaporation in cool air is negligible, the outflow of water is hampered by frost, and the plants have developed adaptations to the economical use of even this seemingly excess moisture. This is not surprising in the deserts of dry lovers shrubs. Why are they in the raw tundra?
The reason for this is draining winds, dehydrating moisture-absorbing fabric, and low activity of the roots, sluggishly absorbing moisture from the cooled soil. At temperatures below zero degrees, the winds are especially destructive - you cannot restore the moisture lost to evaporation from the frozen soil. So you have to not just hide from the wind, but to arm yourself with a whole arsenal of adaptations, like those of real “Sukholubs”. Moisture is better saved by crushed, pubescent, "felt" leaves, for example, are well adapted to conditions of insufficient soil moistening of heather and lingonberry. To reduce evaporation, heather leaves are curled almost into a tube, with the stomata located on the lower, inner surface of the leaves and protected by hairs. Lingonberry has small dotted holes on the bottom surface of the leaf. In these pits is a club-shaped formation, in which the cell walls are filled with mucous substance capable of absorbing water. The water wetting the upper side of the leaf passes to the lower side, fills the hole and is absorbed by the plant.
The spherical shape of the pillow bushes has a minimal evaporating surface, and inside the pillows there is a nicer microclimate - it is damp, windless and even warmer than “outdoors”.
Often, the height of the shrubs corresponds to the depth of the snow cover, since all parts protruding above the snow die (dwarf birch, dwarf willow). In some shrubs and trees, growth in the horizontal direction begins to predominate, for example, in the cedar elfin woods, juniper, mountain ash, etc. large specimens can reach a length of 5 meters with a height above the soil just a few centimeters.
Many plants in the tundra winter in green and under snow! Even evergreen is a sign of plants not only in hot countries. Summer in the tundra is cold, with plenty of sunlight. The continuous polar day under the latitude of the 70th parallel lasts about 64 days. The number of days with an average daily temperature above + 10 ° C in the north of the zone barely reaches 10 and only in the south rises to 30-50. The transition from winter to summer here is strikingly sharp: it barely has time to melt the snow, as the soil becomes covered with green grass and bright colors. This happens because most of the tundra perennials meet summer already with ready-made shoots and leaves, otherwise they simply would not have time to form and ripen the seeds.
Some trees, such as alder, have simultaneously thrown out both earrings, inflorescences, and leaves, for such a short summer.
The forest-tundra is a transitional zone where the forest and the tundra alternate so consistently that it can not be attributed either to the tundra or to the forest zone; therefore, the forest-tundra is considered an independent landscape zone.
Moving from the tundra to the south, you see that the groves of the oppressed trees appear first in strips, along the rivers flowing from the south. Here the trees are helped by the microclimate of the valleys, slightly warmed up by the rivers. All the trees are birch, spruce, and the larches are short, many of them are twisted and bent down to the ground. One type of birch in botanists is officially called the "sinuous birch". The wind, gnawing crowns, gives them one-sided "flag" outlines. But the whole groves of strange fir trees with bunk crowns - their trunks, bare in the lower half, have retained dense branches at the very bases. Below the upper crown, the kidneys are burned out by cutting grounding ground, which makes the trunks “naked”, and the squat crown, like a skirt, remains intact under the protection of a snow cover.
In the frozen and marshy ground, tree roots can not grow in depth, they have to spread in the surface horizons of the soil, forming a kind of stand under the vases. Such root pedestals help trees to maintain stability in strong winds and sodden ground.
Another adaptation to the northern conditions, or rather to the lack of insects - pollinators, in plants is associated with the size and location of the leaves on the shoot.
The general plan for all berry bushes is this: the lower leaves are small, in the middle part of the shoot the largest, and to the top of the shoot they decrease again. This arrangement of leaves in size is determined by two circumstances. First, the closer to the light (that is, the end of the shoot), the larger the lamina. However, secondly, at the very end of the shoot, the leaves are not large, as they open the underlying flowers for pollinating insects. Thus, the largest leaves are located in the middle of the shoot. In the tundra, where the role of pollination by the wind is very large, large cranberry leaves, blueberries are shifted to the beginning and base of the shoot.
Adaptations to life in conditions of insufficient moisture. (Demonstration of herbarium).
1 most characteristic species;
2-life form;
3-relative dimensions of the leaf blade;
4-the presence of pubescence;
5-the presence of wax coating;
6-placement of stomata on the sheet;
7-degree of development of mechanical tissue;
8-type root system by root penetration depth
(surface, intermediate, depth).
|
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
|
cowberry |
shrub (evergreen) |
small |
--- |
there is |
bottom of the sheet |
chorus |
surface |
|
ling |
shrub (evergreen) |
small |
there is |
there is |
bottom of the sheet |
chorus |
surface |
|
blueberry |
bush |
small |
--- |
--- |
bottom of the sheet |
chorus |
surface |
|
cranberry |
shrub (evergreen) |
small |
bottom of the sheet |
there is |
bottom of the sheet |
chorus |
surface |
|
cotton grass |
|
narrow long |
--- |
--- |
bottom of the sheet |
chorus |
surface |
|
wheatgrass creeping |
grass (perennial rhizomatous) |
elongated flat |
top sheet |
--- |
bottom of the sheet |
chorus |
surface |
|
fescue |
grass (perennial rhizomatous) |
narrow long |
weak |
--- |
bottom of the sheet |
chorus |
surface |
|
eyebright chilly |
grass (annual) |
small |
weak |
--- |
bottom of the sheet |
is weak |
poorly developed |
|
blueberries |
bush |
small |
--- |
there is |
bottom of the sheet |
chorus |
surface |
|
dwarf birch |
bush |
small |
--- |
--- |
bottom of the sheet |
chorus |
surface |
|
wormwood |
grass (perennial rhizomatous) |
small |
there is |
--- |
bottom of the sheet |
chorus |
surface |
Conclusions: all the plants studied by us, growing in the tundra, regardless of the life form, have a number of adaptations to the harsh climatic conditions. Among them: small leaf blades, mostly pubescent or covered with wax coating, the stomata are located on the underside of the leaf, the mechanical tissue is well developed, the type of root system is superficial.
Comparative characteristics of coniferous trees found in the forest-tundra, and their adaptability to harsh conditions. (Demonstration of the collection.)
|
plant names |
needles |
cone |
||||
|
length |
coloring |
the form |
branch location |
the size |
scales shape |
|
|
1. Pine ordinary |
5-7 |
green |
sharp, convex on one side and rounded on the other |
sit on 2 together |
up to 8 |
elongated |
|
2.El |
1 |
green |
sharp, tetrahedral, dense |
sit singly, spirally cover the entire branch |
to 10 |
round or pointed |
|
3. Siberian Litty |
2 |
light green |
flat, soft, do not have a dense skin |
sit in bunches of 20-40, like tassels, fall for the winter |
to 10 |
rounded |
|
4. Siberian cedar pine |
6-13 |
green |
tight, sticking out |
collected in bundles of 5 pieces |
up to 13 |
triangular |
|
5.mozhdel-ordinary |
1-2 |
dark green |
acicular, dense |
sit in bunches of 3 pieces |
oh 5-1 |
fleshy, juicy, grow together, form a cone |
Conclusion:
The leaves of coniferous trees are narrow, needle-like. The needles have a dense skin, covered with a waxy substance, so the plants evaporate little water and are well adapted to adverse conditions. (If there is no dense skin, like in larch, the needles fall off.)
Lichens especially feel good in the tundra ( collection demonstration),
striking with its unpretentious beauty: a blue spot appears on the aspen trunk, resembling a warped enamel paint, a grayish-turquoise scaly patina on a birch tree, blood-red on some alder branches, there is no loose shred on the ground that is not occupied by lichen, they cover the soil solid white carpet. The shape of lichens is also varied. Some look like bushes, others look like plates of the most bizarre outlines, others look like hard crusts so tightly attached to stones that they cannot be torn off, the fourth ones - beards.
Here, in the tundra, there is the main thing that is necessary for the life of lichens: high humidity. The saturation of its water vapor. And one more prerequisite: clean air. Therefore, the lichen can serve as a determinant of the state of the atmosphere: it grows well - the air is clean, it dies - it is polluted.
But no matter how unpretentious lichens turned out to be, yet they also adapted to the harsh conditions of the tundra. Lichens of the temperate zone are capable of photosynthesis at temperatures from +25 to -13 ° C. In polar conditions, these plants are adapted to the constant effects of negative temperature, and they have a shift in the temperature optimum to –25ºС. Arctic lichens have adapted to life and photosynthesis, even while under cover of snow with very little light. Most lichens tolerate frost freezing in the state of anabiosis in the winter season and after thawing they turn out to be quite viable. Some lichens are able to withstand low temperatures, at which all physiological processes are suspended, for more than two years.
Life in the tundra is extremely vulnerable, and it is easy to undermine it irreparably. Pastures are threatened with overgrazing, but this is not the most dangerous thing: even wild reindeer prevent such a threat by moving from place to place. Worse, new methods of undermining its long-established equilibria have hit the tundra. Especially terrible fire, no less disastrous for it than for forests. The moss-burned moss does not recover for decades. In frozen soils, the tracks from all-terrain vehicles do not heal for years. Because of the laying of pipelines for oil and gas, the paths of reindeer migrations were doomed to overgrazing of pastures and starvation of the herd; Now designers are providing arched passages for deer under the pipes.
Lichens listed in the Red Book grow in the tundra (29 species in the Red Book of the USSR). (Slideshow).) Among them: Green Coristium is a rare species. It grows on peatlands and plant residues in bog communities. It is reduced due to the disturbance of the natural balance in the marsh complexes Usney blooming - a shrinking species. It grows on trees. Reduced due to active collection for medical purposes. Letharius wolf - a rare species (poisonous). Used to kill carnivores. Grows on coniferous trees, less often - on rotting wood. Reduced due to indiscriminate charges by the population.
Conclusions on the work.
On the basis of the work done (collection of collection and herbarium material, analysis of the collected exhibits, selection of the necessary photographs and the study of scientific literature), we can formulate the following conclusions:
In the plants of tundra and forest-tundra, in the process of their historical development, adaptations were developed (especially in the structure and in the processes of vital activity), allowing them to live and develop normally in specific (hard) environmental conditions.
All of the plants we studied that grow in the tundra, regardless of life form, have a number of adaptations to the harsh climatic conditions. Among them: small leaf blades, covered with hair or wax coating, the stomata are located on the underside of the leaf, the mechanical tissue is well developed, the type of root system is superficial.
Coniferous trees also have adaptations to the harsh environmental conditions: narrow, needle-like leaves - needles, of various lengths, shapes and locations on a branch, covered with a waxy substance that slows down the evaporation of water.
Literature:
1.T.A.Turskova. Planet Earth. Polar latitudes. - M .: “Veche”, 2002.
2.Yu.K.Efremov. The nature of my country. - M .: "Thought", 1985.
3. Yu.Dmitriev, N.Pozharnitskaya, A.Vladimirov, V.Porudominsky. The book of nature. - M .: Children's literature, 1990.
4. Life of plants. V.3. Seaweed. Lichens. - M .: "Enlightenment", 1977.
5. E.Ya. Chernikhov. Study tours of geography. - M .: "Enlightenment", 1980.
6.V.V.Pasechnik. Biology. Bacteria. Mushrooms Lichens. - M .: "Bust", 2001.
7. S.G.Mamontov. Biology. - M .: "Bustard", 1995.
8.VS.Novikov, I.A.Gubanov. School atlas-determinant of higher plants: a book for students. - M .: "Enlightenment", 1985.
9.Methodical instructions for the implementation of laboratory and independent work on botany with the basics of ecology. - Penza, 1987.
10. "What will tell the escape of lingonberries." Biology at school. No. 1, 1988.
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Tundra type of vegetation is formed in a short and cool summer, high humidity and low temperature of the soil. It is a small amount of heat that determines the main features of this type: woodlessness, mosaic (spotting), the predominance of mosses, lichens, shrubs and, in part, shrubs, short stature, the dominance of perennials.
Tundra type of vegetation - education is young. Many researchers associate its appearance with the ancient glaciation, therefore, consider the Pleistocene formation, but there is also an opinion that the occurrence of tundra floristic complexes belongs to the Pliocene. The number of species of tundra flora in Russia does not exceed 300-400. The poverty of the species composition of the tundra type of vegetation is associated with both its youth and the severity of the conditions in which it is formed.
Of the many factors unfavorable to plant life, one of the most important is the lack of heat, which is why cryophytes dominate here. In an effort to use the heat of the uppermost horizon of the soil and the surface layer of air, each of which is measured in just a few centimeters, the plants are pressed to the ground. It is not surprising, therefore, that many tundra plants are very short. They are spread on the ground, and their roots grow mainly in the horizontal direction and almost do not go into the depths. Creeping and pillow forms are widespread. Many plants have leaves collected in the rosette.
Due to their low stature, tundra plants not only most fully utilize the heat of the surface layer of air and protect themselves from enhanced evaporation caused by strong winds, but also become covered in winter with snow, protecting them from freezing.
Tundra plants are predominantly perennials, including almost all herbaceous plants. Annual grasses are extremely few, so how to go full life cycle for a few weeks is extremely difficult. This requires a very rapid pace of development in conditions low temperatures. Bulbous and tuberous plants are almost completely absent, since late-thawing soil with permafrost is unfavorable for their growth. True, there are live-bearing plants. This is a kind of adaptation to the reproduction of offspring in conditions where the seeds do not mature every year. In the inflorescences of such plants (for example, the mountaineer) instead of flowers, onions or nodules develop, which, having fallen to the ground, take root and give rise to a new escape.
There are many evergreen plants in the tundra: water plant (crowberry), lingonberry, dryad, Cassandra, cranberry, wild rosemary, etc. This allows them to use radiant energy for photosynthesis with the onset of the first warm days, without losing time for the formation of leaves.
Extremely interesting feature tundra plants is the presence of their devices aimed at reducing evaporation, ie, xeromorphism, due to physiological dryness. Cold water remains almost inaccessible to plants, so they are forced to reduce evaporation. The plants are dominated by small leaves with a small evaporating surface. The underside of the leaves, on which the stomata are located, is covered with dense pubescence, which prevents too much air movement near the stomata and, therefore, reduces evaporation. In some plants (for example, in the crowberry) the leaves are curled into a tube. The stoma, located on the lower side of the leaf, is inside it, which also leads to a decrease in evaporation. A number of plants have leathery leaves (lingonberries, cranberries, dryad, etc.).
One of the main features of tundra communities is their polydominance. Although tundras are divided into moss, lichen, shrub or cotton grass-sedge, they almost always contain mosses, lichens, shrubs, perennial herbaceous plants, often shrubs, in different, but often close, combinations.
Mosses and lichens play a very important role in tundra vegetation type. These unpretentious plants may exist under the protection of even a thin snow cover, and sometimes even without it. Shrubs and bushes are not only evergreen, but also with falling foliage (willows, dwarf birch, blueberries, arctous, etc.). Among perennial herbaceous plants there are grasses (alpine meadow, arctic bluegrass, alpine foxtail, etc.), sedge (tough sedge, etc.), legumes (umbrella astragalus, kopeechnik obscure, etc.), but most of the plants belong to raznotravy (alpine basilica, rhodiola rosea, bathing suit, white-flowered geranium, forget-me-nots, Eder's mytnik, etc.). A characteristic feature of tundra forbs is large, brightly colored flowers: yellow, white, crimson, orange, blue, etc.
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