Forests, the lungs of the planet? Conversation “Forests are the lungs of our planet” What are the lungs of our planet
home There is an opinion that " lungs of the planet
"are forests, since it is believed that they are the main suppliers of oxygen to the atmosphere. However, in reality this is not the case. The main producers of oxygen live in the ocean. These babies cannot be seen without the help of a microscope. But all living organisms on Earth depend on their livelihoods.
No one argues that forests, of course, need to be preserved and protected. However, not at all because they are these notorious “lungs”. Because in fact, their contribution to the enrichment of our atmosphere with oxygen is practically zero. No one will deny the fact that the oxygen atmosphere of the Earth was created and continues to be maintained by plants. This happened because they learned to create organic substances from inorganic ones, using energy sunlight (as we remember from school course
biology, a similar process is called photosynthesis). As a result of this process, plant leaves release free oxygen as a by-product of production. This gas, which we need, rises into the atmosphere and is then evenly distributed throughout it. According to various institutes, thus, about 145 billion tons of oxygen are released into the atmosphere on our planet every year. Wherein most of
it is spent, not surprisingly, not on the respiration of the inhabitants of our planet, but on the decomposition of dead organisms or, simply put, on decay (about 60 percent of what is used by living beings). So, as you can see, oxygen not only gives us the opportunity to breathe deeply, but also acts as a kind of stove for burning garbage.
As we know, any tree is not eternal, so when the time comes, it dies. When the trunk of a forest giant falls to the ground, its body is decomposed by thousands of fungi and bacteria over a very long period of time. All of them use oxygen, which is produced by surviving plants. According to researchers' calculations, such “cleaning up the territory” consumes about eighty percent of the “forest” oxygen. But the remaining 20 percent of oxygen does not enter the “general atmospheric fund” at all, and is also used"on the ground" for their own purposes. After all, animals, plants, fungi and microorganisms also need to breathe (without oxygen, as we remember, many living beings would not be able to obtain energy from food). Since all forests are usually very densely populated areas, this residue is only enough to satisfy the oxygen needs of only its own inhabitants. There is nothing left for neighbors (for example, residents of cities where there is little native vegetation).
Who, then, is the main supplier of this gas necessary for breathing on our planet? On land these are, oddly enough... peat bogs. Everyone knows that when plants die in a swamp, their organisms do not decompose, since the bacteria and fungi that do this work cannot live in swamp water - there are many natural antiseptics secreted by mosses.
So, dead parts of plants, without decomposing, sink to the bottom, forming peat deposits. And if there is no decomposition, then oxygen is not wasted. Therefore, swamps contribute about 50 percent of the oxygen they produce to the general fund (the other half is used by the inhabitants of these inhospitable, but very useful places).
Nevertheless, the contribution of swamps to the total " charitable foundation oxygen" is not very large, because there are not so many of them on Earth. Microscopic ocean algae, the totality of which scientists call phytoplankton, are much more actively involved in “oxygen charity”. These creatures are so small that it is almost impossible to see them with the naked eye. However, their total number is very large, amounting to millions of billions.
The entire world's phytoplankton produces 10 times more oxygen than it needs for breathing. Enough to provide useful gas to all other inhabitants of the waters, and quite a lot gets into the atmosphere. As for the oxygen consumption for the decomposition of corpses, in the ocean they are very low - approximately 20 percent of the total production.
This happens due to the fact that dead organisms are immediately eaten by scavengers, of which there are a great many living in sea water. Those, in turn, will be eaten by other scavengers after death, and so on, that is, corpses almost never lie in the water. The same remains, which are no longer of particular interest to anyone, fall to the bottom, where few people live, and there is simply no one to decompose them (this is how the well-known silt is formed), that is, in this case, oxygen is not consumed.
So, the ocean supplies the atmosphere with about 40 percent of the oxygen that phytoplankton produced. It is this reserve that is consumed in those areas where very little oxygen is produced. The latter, in addition to cities and villages, include deserts, steppes and meadows, as well as mountains.
So, oddly enough, the human race lives and thrives on Earth precisely due to the microscopic “oxygen factories” floating on the surface of the ocean. It is they who should be called “the lungs of the planet.” And protect in every possible way from oil pollution, heavy metal poisoning, etc., because if they suddenly stop their activities, you and I will simply have nothing to breathe.
Nature has created a magnificent forest country for us. He greets us with a sea of sounds and smells, hundreds of riddles and secrets. The forest is a home for birds, animals and other animals. Here they feed, hide from their enemies, and raise their offspring. The more diverse the forest, the more species of trees, shrubs, grasses it contains, the richer and animal world. All components of the forest are in a certain biological balance. If this balance is disturbed, nature itself restores it. For example, if there is a wolf in the forest, there is always a normal elk herd. Learn to walk in the forest. Yes, you need to be able to walk through the forest in order not only to notice the beauty around you, but also to penetrate its secrets without disturbing the usual routine of life of its inhabitants. You need to firmly remember the rule: he who walks slowly and silently sees and hears a lot. Then you will certainly be lucky: you will see how the birds feed their chicks in the nests, how the prickly family of hedgehogs and hedgehogs travel in a row.....
Forests are the invaluable wealth of our Motherland. They protect and regulate the life of rivers, have a positive effect on the climate, soil, and water regime of fields. Forests are the lungs of our planet. They supply oxygen and absorb carbon dioxide. How to get acquainted with the forest? It is best to consider its tiers - “floors”. The tallest ones are formed by trees; under the canopy of the tree stand, undergrowth, shrubs, grass and moss cover grow. There are many beautiful herbs growing in the forest.
So what is a forest? This is not just a collection of trees and shrubs, but thousands of organisms connected to each other. These include soils, grass cover, mosses, lichens, mushrooms, insects, animals, birds, etc. Forest - the whole complex organisms living according to their own laws and rules. Everything in the forest is so interconnected that as soon as one “particle” changes, everything else changes. For example, forests protect the full flow of rivers, which means that ships are not afraid of shoals and riffles, fields are not afraid of a lack of moisture, fish are provided with good spawning grounds, and meadows are provided with lush grass. If you cut down a forest along a river, the water will lose its natural protection: evaporation from the surface of the water will increase, shallows will appear, it will become difficult for the fish to breathe, and they will gradually die. And if so, the animals and birds that ate fish gradually disappear. Forests appeared on Earth 300 million years ago. More than 30 thousand various types trees and shrubs form the basis of the forests of our planet. Under the influence of wind, sun and moisture, they form Various types forests: coniferous, broad-leaved, mixed, tropical and others, characteristic of each natural belt. Forests are the lungs of our planet, helping all living things breathe. The fate of oxygen on our planet worries people more and more. If the entire population of the globe consumes 1.2 billion tons of oxygen per year, then transport is many times more. So a car, having covered 1000 km, consumes as much oxygen as one person needs to breathe for a year. An airplane in flight burns 50-100 tons of oxygen in 8 hours. On average, forests emit more than 55 billion tons of oxygen per year. Just one hectare of forest supplies oxygen to up to 2000 people per year, purifies 18 million m3 of air from carbon dioxide, and absorbs 64 tons of other gases and dust. Rainwater, taking particles of dust, dirt, and gases from the air, falls on the leaves and flows down them to the ground. As a result, accumulating in forest reservoirs, it contains 20-30 times less dirt and bacteria than drops of the same rain falling over a meadow or arable land. There are 300 times fewer bacteria in forest air than in city air. Forests clean the air of dust, increasing the transparency of the atmosphere, and at the same time reduce the harmful effects of direct solar radiation, reducing it by 7 times. Scientists have found that a dense spruce forest retains up to 99% of solar radiation, and a pine forest - 96%.
This rebus contains an encrypted appeal to all people living on the planet.
The forest brings many gifts to people: wood and its products, as well as fruits. mushrooms, berries and nuts. Each forest has its own world of animals. Wood occupies the main place among forest products. From it, man learned to produce various products. As a result of chemical processing of wood, we obtain rubber, resins, glue, paper, soap, medicines, etc.
Question: What is a forest? Why are forests called “the lungs of the planet”?
Think about it!
The area of forests on Earth is being halved. They are cut down and burned so that after certain time they may disappear from the face of the earth.
ABC of folk wisdom
A man chops a birch tree, and the wood chips hit the mushrooms and berries.
"In the forest"
One is a path; a thousand people - a trail in the forest; leaves a hundred desert.
Here, by rearranging words and signs, a saying is encrypted about how people can cause irreparable harm to the forest.
Since ancient times, people have been going to the forest for its gifts or just to relax and enjoy the singing of birds. “Love” for the forest sometimes turns to its detriment. Imagine how, on a fine sunny day, hundreds and even thousands of people rush into the forest. Suburban forests have long been unable to withstand such loads. The pine forest is especially vulnerable. It gets sick from trampling faster than a spruce or birch forest. The forest soil, compacted by thousands of feet, loses its structure and air does not pass through it well. Because of this, tree seedlings die, and plants from other communities that are less demanding on soil quality, for example, meadows, settle in the forest. They, in turn, choke out tiny trees and shrubs. Many people like to make fires in the forest. And the “wound” from a fire on the ground does not heal for 5–7 years. Each of you has probably paid attention to knocked down fly agarics or, more simply, “bad” mushrooms, uprooted strawberry plants, moss turned upside down in search of mushrooms. If you were in a cedar forest during the ripening of cones (pine nuts), then you probably felt uneasy at the sight. Broken and sawn branches, and even the tops of cedars, lie under the trunks of cedars. People take gifts from the forest, not caring at all about the consequences. If something like a fly agaric is not edible for humans, then it must be destroyed and trampled. Such people have no place in the forest. A man in the forest is a guest, and he must behave appropriately. You need to pick mushrooms, berries and nuts very carefully so as not to harm the plant as a whole. If you collect mushrooms correctly, without damaging the mycelium, then they will grow in this place not only for one mushroom season, but also within several years! And ripe cedar cones can be collected at the end of August - at the beginning of September under the canopy of trees. At this time, they ripen and easily separate from the branches and fall to the ground. Enjoy your health! Imagine how many ants and other beneficial insects die under our feet! By talking loudly, you can scare away birds that are hatching or even feeding chicks from their nests. So – what to do? Don't go into the forest at all! Of course not. But you need to respect its laws and its inhabitants.
Exercise: /Choose the correct answer/
In order not to harm the forest we must:
1. Don’t go into the forest at all.
2. Go to the forest 3-4 times a year.
3. Walk into the forest and respect its laws and its inhabitants.
ABC of folk wisdom
1. He who cuts down forests dries out places.
2. A swan in the sky, a butterfly above the earth - each has its place.
There is a misconception that has even found its way into textbooks: forests are the lungs of the planet. Forests actually produce oxygen and the lungs consume it. So this is rather an “oxygen cushion”. So why is this statement a misconception? In fact, oxygen is produced not only by those plants that grow in the forest. All plant organisms, including inhabitants of reservoirs, and inhabitants of steppes and deserts, constantly produce oxygen. Plants, unlike animals, fungi and other living organisms, can synthesize organic substances themselves, using light energy for this. This process is called photosynthesis. As a result of photosynthesis, oxygen is released. It is a by-product of photosynthesis. A lot of oxygen is released, in fact, 99% of the oxygen that is present in the Earth’s atmosphere plant origin. And only 1% comes from the mantle, the underlying layer of the Earth.
Of course, trees produce oxygen, but no one thinks about the fact that they also waste it. And not only them, all other inhabitants of the forest cannot be without oxygen. First of all, plants respire on their own, this happens in the dark when photosynthesis does not occur. And we need to somehow utilize the reserves of organic substances that they created during the day. That is, feed yourself. And in order to eat you need to spend oxygen. Another thing is that plants spend much less oxygen than they produce. And this is ten times less. However, we should not forget that in the forest there are still animals, as well as mushrooms, as well as various bacteria that do not produce oxygen themselves, but nevertheless breathe it. A significant amount of oxygen that the forest produced during daylight hours will be used by living organisms of the forest to support life. However, something will remain. And this is something like 60% of what the forest produces. This oxygen enters the atmosphere, but does not remain there for very long. Then the forest itself removes oxygen, again for its own needs. Namely, the decomposition of the remains of dead organisms. Ultimately, forests often spend 1.5 times more oxygen to dispose of their own waste than they produce. After this, it cannot be called the oxygen factory of the planet. True, there are forest communities that operate on a zero oxygen balance. These are famous rainforests.
The tropical forest is generally a unique ecosystem; it is very stable, because the consumption of substances is equal to production. But again, there was no surplus left. So even tropical forests can hardly be called oxygen factories.
So why then, after the city, does it seem to us that the forest is clean, Fresh air that there is a lot of oxygen there? The thing is that oxygen production is very fast process, but consumption is a very slow process.
So what then are the oxygen factories of the planet? There are actually two ecosystems. Among the “land” ones are peat bogs. As we know, in a swamp the process of decomposition of dead matter is very, very slow, as a result of which dead parts of plants fall down, accumulate, and peat deposits are formed. Peat does not decompose, it is compressed and remains in the form of a huge organic brick. That is, during peat formation, a lot of oxygen is not wasted. Thus, swamp vegetation produces oxygen, but consumes very little oxygen itself. As a result, it is the swamps that provide exactly the increase that remains in the atmosphere. However, there are not so many real peat bogs on land, and of course it is almost impossible for them alone to maintain the oxygen balance in the atmosphere. And here another ecosystem helps, called the world ocean.
There are no trees in the world's oceans; grasses in the form of algae are observed only near the coast. However, vegetation still exists in the ocean. And most of it consists of microscopic photosynthetic algae, which scientists call phytoplankton. These algae are so small that it is often impossible to see each of them with the naked eye. But the accumulation of them is visible to everyone. When bright red or bright green spots are visible on the sea. This is phytoplankton.
Each of these little algae produces great amount oxygen. It consumes very little itself. Due to the fact that they rapidly divide, the amount of oxygen they produce increases. One phytoplankton community produces 100 times more per day than a forest occupying the same volume. But at the same time they spend very little oxygen. Because when algae die, they immediately fall to the bottom, where they are immediately eaten. After that, those who ate them are eaten by other, third organisms. And so few remains reach the bottom that they quickly decompose. There is simply no decomposition that lasts as long as in the forest, in the ocean. There, recycling occurs very quickly, as a result of which oxygen is virtually not wasted. And so the “big profit” occurs, and so it remains in the atmosphere. So the “lungs of the planet” should be considered not forests at all, but the world’s oceans. He is the one who makes sure that we have something to breathe.
Rainforests located in the tropical, equatorial and subequatorial zones between 25° north latitude. and 30° S, as if “surrounding” the surface of the Earth along the equator. Rainforests are broken only by oceans and mountains.
The general circulation of the atmosphere occurs from a zone of high atmospheric pressure in the tropical region to a zone of low pressure in the equator region, and evaporated moisture is transported in the same direction. This leads to the existence of a humid equatorial zone and a dry tropical one. Between them there is a subequatorial belt, in which moisture depends on the direction of the monsoons, depending on the time of year.
Vegetation tropical forests very diverse, depending mainly on the amount of precipitation and its distribution over the seasons. When abundant (more than 2000 mm), and relatively uniform distribution develop tropical humid evergreen forests.
Further from the equator, the rainy period gives way to a dry period, and forests are replaced by leaves falling during drought, and then these forests are replaced by savanna forests. At the same time, in Africa and South America There is a pattern: from west to east, monsoon and equatorial forests are replaced by savanna forests.
Classification of tropical forests
Tropical rainforest, tropical rain forest these are forests with specific biomes located in equatorial (equatorial rainforest), subequatorial and humid tropical areas with a very humid climate (2000-7000 mm of precipitation per year).
Tropical rainforests are characterized by enormous biodiversity. This is the most conducive to life natural area. Lives here a large number of own, including endemic species of animals and plants, as well as migratory animals. Two-thirds of all animal and plant species on the planet live in tropical rainforests. It is estimated that millions of animal and plant species remain undescribed.
These forests are sometimes called " jewels of the earth" And " the largest pharmacy in the world” as a large number of natural medicines have been found here. They are also called " lungs of the Earth", however, this statement is controversial, since it does not have scientific justification, since these forests either do not produce oxygen at all or produce very little of it.
But it should be borne in mind that a humid climate promotes effective air filtration due to the condensation of moisture on microparticles of pollution, which has a generally beneficial effect on the atmosphere.
Understory formation in tropical forests is severely limited in many places due to the lack of sunlight in the understory. This allows humans and animals to move through the forest. If for some reason the deciduous canopy is absent or weakened, the lower tier is quickly covered with a dense thicket of vines, shrubs and small trees - this formation is called a jungle.
The largest areas of tropical rainforest are found in the Amazon Basin (“ rain forests Amazon"), in Nicaragua, in the southern part of the Yucatan Peninsula (Guatemala, Belize), in most of Central America (where they are called "selva"), in equatorial Africa from Cameroon to Democratic Republic Congo, in many areas South-East Asia from Myanmar to Indonesia and New Guinea, in the Australian state of Queensland.
For tropical rainforests characteristic:
- variety of flora,
- presence of 4-5 tree layers, absence of shrubs, large number of vines
- predominance evergreen trees with large evergreen leaves, poorly developed bark, buds not protected by bud scales, in monsoon forests– deciduous trees;
- the formation of flowers and then fruits directly on trunks and thick branches
Trees in tropical rainforests have several general characteristics, which are not observed in plants of less humid climates.
The base of the trunk in many species has wide, woody projections. Previously, it was assumed that these protrusions help the tree maintain balance, but now it is believed that water with dissolved nutrients flows along these protrusions to the roots of the tree. The broad leaves of trees, shrubs and grasses of the lower tiers of the forest are characteristic. Wide leaves help plants better absorb sunlight under the edges of the trees of the forest, and they are protected from the wind from above.
Tall young trees that have not yet reached the top tier also have wider foliage, which then decreases with height. The leaves of the upper tier, forming a canopy, are usually smaller in size and heavily grooved to reduce wind pressure. On the lower floors, the leaves are often narrowed at the ends so that this facilitates the rapid drainage of water and prevents the growth of microbes and moss on them, which destroy the leaves.
Tree tops are often very well connected with each other using vine or epiphytic plants, fixed on them.
The trees of the tropical rainforest are characterized by unusually thin (1-2 mm) tree bark, sometimes covered sharp thorns or thorns, the presence of flowers and fruits growing directly on tree trunks, a wide variety of juicy fruits that attract birds and mammals.
In tropical rainforests there are a lot of insects, especially butterflies (one of the richest faunas in the world) and beetles, and in rivers there are a lot of fish (about 2000 species, approximately a third of the world's freshwater fauna).
Despite the lush vegetation, the soil in tropical rainforests is thin and has a small humus horizon.
Rapid rotting caused by bacteria prevents the accumulation of a humus layer. The concentration of iron and aluminum oxides due to laterization Soil dehydration (the process of reducing silica in the soil while increasing iron and aluminum oxides) turns the soil bright red and sometimes forms mineral deposits (such as bauxite). But on rocks of volcanic origin, tropical soils can be quite fertile.
Levels (tiers) of tropical rainforest
The rainforest is divided into four main levels, each of which has its own characteristics and has different flora and fauna.
Top level
This tier consists of a small amount of very tall trees, rising above the forest canopy, reaching a height of 45-55 meters ( rare species reach 60-70 meters). Most often the trees are evergreen, but some shed their leaves during the dry season. Such trees must withstand harsh temperatures and strong winds. Eagles live on this level, the bats, some species of monkeys and butterflies.
Crown level (forest canopy)
The crown level is formed by most tall trees, usually 30-45 meters high. This is the densest layer known in all of Earth's biodiversity, with neighboring trees forming a more or less continuous layer of foliage.
According to some estimates, plants of this tier make up approximately 40 percent of the species of all plants on the planet - perhaps half of the entire flora of the Earth can be found here. The fauna is similar to the upper level, but more diverse. It is believed that a quarter of all insect species live here.
Scientists have long suspected the diversity of life at this level, but have only recently developed practical methods research. It was not until 1917 that the American naturalist William Beed declared that “another continent of life remains unknown, not on the earth, but 200 feet above its surface, extending over thousands of square miles.”
Real exploration of this layer only began in the 1980s, when scientists developed techniques to reach the forest canopy, such as shooting ropes into the treetops with crossbows. Forest canopy research is still underway early stage. Other research methods include travel on balloons or aircraft. The science of reaching treetops is called dendronautics.
Average level
Between the forest canopy and the forest floor there is another level called the understory. It is home to a number of birds, snakes and lizards. Insect life at this level is also very extensive. The leaves in this tier are much wider than at the crown level.
forest floor
IN Central Africa in the tropical primary forest of Mount Virunga, illumination at ground level is 0.5%; in the forests of southern Nigeria and in the Santarem region (Brazil) 0.5-1%. In the north of the island of Sumatra in the dipterocarp forest, the illumination is about 0.1%.
Away from river banks, swamps and open spaces where dense, low-growing vegetation grows, the forest floor is relatively free of plants. At this level you can see rotting plants and animal remains, which quickly disappear thanks to the warm, humid climate, promoting rapid decomposition.
Selva(Spanish: " selva" from lat. " silva"- forest) is equatorial rainforests in South America. Located in countries such as Brazil, Peru, Suriname, Venezuela, Guyana, Paraguay, Colombia, etc.
The selva is formed on vast low-lying areas of land under conditions of constant freshwater moisture, as a result of which the soil of the selva is extremely poor in minerals washed out by tropical rains. Selva is often swampy.
The flora and fauna of the selva is a riot of colors and a variety of species of plants, birds and mammals.
The largest village in terms of area is located in the Amazon basin in Brazil).
In the Atlantic jungle, precipitation reaches two thousand millimeters per year, and humidity fluctuates at 75-90 percent.
The village is divided into three levels. The soil is covered with leaves, branches, trunks of fallen trees, lichens, fungus and moss. The soil itself is reddish in color. The first level of the forest consists of low plants, ferns and grass. The second level is represented by shrubs, reeds and young trees. On the third level there are trees from twelve to forty meters high.
Mangroves – evergreen deciduous forests, common in the tidal zone sea coasts in tropical and equatorial latitudes, as well as in zones with a temperate climate, where warm currents favor it. They occupy the space between the most low level water during low tide and highest during high tide. These are trees or shrubs that grow in mangroves, or mangrove swamps.
Mangrove plants live in sedimentary coastal environments where fine sediments, often high in organic matter, accumulate in areas protected from wave energy.
Mangroves have an exceptional ability to exist and develop in a saline environment on soils deprived of oxygen.
Once established, mangrove plant roots create habitat for oysters and help slow water flow, thereby increasing sedimentation in areas where it is already occurring.
Typically, fine, oxygen-poor sediments beneath mangroves act as reservoirs for a wide variety of heavy metals (trace metals) that are captured from sea water colloidal particles in sediments. In those areas of the world where mangroves were destroyed during the development of the territory, the violation of the integrity of these sedimentary rocks gives rise to the problem of pollution of sea water with heavy metals and local flora and fauna.
It is often argued that mangroves provide significant coastal value, acting as a buffer against erosion, storms and tsunamis. Although there is a definite reduction in wave height and wave energy as seawater passes through mangroves, it must be recognized that mangroves typically grow in areas of the coastline where low wave energy is the norm. Therefore, their ability to withstand the powerful onslaught of storms and tsunamis is limited. Their long-term impact on erosion rates is also likely to be limited.
Many river channels meandering through mangrove areas actively erode the mangroves to outside all the bends of the river, just as new mangroves appear on inside the same bends where deposition occurs.
Mangroves provide habitat for wildlife, including a number of commercial fish and crustacean species, and, in at least some cases, mangrove carbon export is associated with important in the coastal food web.
In Vietnam, Thailand, the Philippines and India, mangroves are grown in coastal areas for inshore fisheries.
Despite ongoing mangrove breeding programs, More than half of the world's mangroves have already been lost..
The floristic composition of mangrove forests is relatively uniform. Mangrove forests of the eastern formation (the shores of the Malacca Peninsula, etc.) are considered the most complex, tall and multi-species.
Misty forest (moss forest, nephelogia) – tropical moist montane evergreen forest. Located in the tropics on the slopes of mountains in a zone of fog condensation.
The foggy forest is located in the tropics on the slopes of mountains in a zone of fog condensation, usually starting at altitudes of 500-600 m and reaching heights of up to 3500 meters above sea level. It is much cooler here than in the jungles located in low-lying areas; at night the temperature can drop to almost 0 degrees. But here it is even more humid; up to six cubic meters of water fall per square meter per year. And if it doesn’t rain, then the moss-covered trees stand shrouded in fog caused by intense evaporation.
Foggy forest formed by trees with abundant lianas, with a dense cover of epiphytic mosses.
Tree ferns, magnolias, camellias are characteristic; the forest may also include non-tropical vegetation: evergreen oaks, podocarpus, which distinguishes this type forests from the plain gils
Variable tropical rainforests- forests common in tropical and equatorial belts, in a climate with a short dry season. Located south and north of the wetlands equatorial forests. Variably humid forests are found in Africa (CAR, DR Congo, Cameroon, northern Angola, extreme south of Sudan), South America, India, Sri Lanka, and Indochina.
Variable rainforests are partly deciduous, dense tropical forests. They differ from humid tropical forests in lower species diversity and in the reduced number of epiphytes and lianas.
Dry tropical evergreen forest. Located in areas with an arid climate, while remaining dense and evergreen, they become stunted and xeromorphic.
HUMAN IMPACT ON TROPICAL FORESTS
Contrary to popular belief, tropical rainforests are not large consumers of carbon dioxide and, like other established forests, are carbon neutral.
Recent studies show that most rain forests are, on the contrary, intensively produce carbon dioxide, and swamps produce methane.
However, these forests play a significant role in the circulation of carbon dioxide because they are established reservoirs, and cutting down such forests leads to an increase in carbon dioxide in the Earth's atmosphere. Tropical rainforests also play a role in cooling the air that passes through them. That's why tropical rainforests - one of the most important ecosystems on the planet, the destruction of forests leads to soil erosion, a reduction in species of flora and fauna, and shifts in the ecological balance large areas and on the planet as a whole.
Tropical rainforests They are often used for plantations of cinchona and coffee trees, coconut palms, and rubber trees. In South America, tropical rainforests are also seriously threatened by unsustainable mining.
A.A. Kazdym
List of used literature
- M. B. Gornung. Constantly humid tropics. M.: “Thought”, 1984.
- Hogarth, P. J. The Biology of Mangroves. Oxford University Press, 1999.
- Thanikaimoni, G., Mangrove Palynology, 1986
- Tomlinson, P. B. The Botany of Mangroves, Cambridge University Press. 1986:
- Jayatissa, L. P., Dahdouh-Guebas, F. & Koedam, N. A review of the floral composition and distribution of mangroves in Sri Lanka. Botanical Journal of the Linnean Society, 138, 2002, 29-43.
- http://www.glossary.ru/cgi-bin/gl_sch2.cgi?RSwuvo,lxqol!rlxg
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Meeting 58. EDUCATIONAL PROJECT “WHY ARE FORESTS CALLED “LIGHTS OF THE PLANET”?”
Target: teach students to find and systematize information about the importance of forests for the Earth; learn to analyze, draw conclusions based on your own observations of environment, understand the meaning of the forest; develop observation and curiosity; cultivate a caring attitude towards plants.
During the classes
I. ORGANIZATIONAL MOMENT
II. UPDATING BACKGROUND KNOWLEDGE
1. Answers to questions in the section “Questions and tasks for those who want to understand nature” (p. 170)
2. Work in groups
Go through the maze. Read the code.
So, what planet is this code from, who needs help? (Inhabitants of the planet Ria)
Do you know about this planet?
I suggest listening to an audio recording about the planet Ria.
Planet Ria is a young planet of the Galaxy. Its territory is dominated by sandy soils. The climate is warm and humid. Sufficient amount of sunlight and warmth. There are many freshwater lakes and rivers. The population is large. The planet suffers from a lack of oxygen and needs help.
3. Exercise “Microphone”
Have you heard the information about climatic conditions planet Ria. How can you help aliens? (Send oxygen cylinders; plant a lot of trees, flowers and other plants.)
Whose proposal do you find useful? Why? (The teacher leads students to the idea that forests are the “lungs” of the planet. Therefore, greening the planet is the most rational idea.)
III. MESSAGE OF THE TOPICS AND OBJECTIVES OF THE LESSON
Today in class you will learn... (Students read the section “Key Question.”)
IV. LEARNING NEW MATERIAL
1. Work in groups
Game “Complete the sentence”
If you look at our planet from space, you can see two primary colors, which seem to be divided Earth into two huge spaces - an ocean of water and an ocean of vegetation.
The amazing world of nature... It greets us with a sea of sounds, smells, riddles and secrets. Makes you listen, look, think.
Remember what you know about the forest, complete and continue the sentences.
There are three types of forests: ..., ... and... Forests in which only oak, beech, captain, ash, birch, alder, poplar, maple, linden trees grow are called... The northern part of Ukraine, where The forest zone is predominantly located, also called... ... In coniferous forests Common tree species are..., ..., ... (pine, spruce, fir, larch, juniper, yew).
2. Work in pairs
Make a diagram showing the conditions necessary for the development and life of a plant. (The living conditions of plants are the presence of soil, moisture, light and heat.)
Remember, all these components are on the planet Ria? (Yes, they all exist.)
Then we can grow various plants on it? (So)
For what purpose do we propose to plant forests on planet Ria? (So that they have clean air enriched with oxygen.)
How many of you can explain to aliens how the process of oxygen formation occurs? Which one of you will tell us how, when and what plants breathe? (The respiratory organs of plants are leaves, through which they absorb carbon dioxide and oxygen, and release oxygen into the air, which is necessary for living beings. What more plants, the cleaner the air will be.)
3. Teacher's story
Forest. How much these three letter Forests have absorbed - this is the “oxygen workshop”, “lungs of the planet”, “green gold”.
One tree average size in 25 hours it provides enough oxygen to breathe for three people.
Without oxygen there is no life. A person can survive without food for several weeks, without water for several days, and without air he dies within a few minutes. The entire supply of oxygen on Earth would have dried up long ago if its reserves were not replenished thanks to green leaves.
Plants provide oxygen, and therefore life. Forests - real factory oxygen. That’s why it’s so easy and deep to breathe in the forest, where billions of tiny green “factories” saturate the air with oxygen.
Forest plants release huge amounts of oxygen and absorb a lot of carbon dioxide. One hectare of forest absorbs as much carbon dioxide in an hour as is produced by the breathing of two hundred people!
The leaves of many trees release special substances into the air - phytoncides. They kill pathogenic bacteria.
Forests greatly contribute to the purification of air from dust and soot and prevent their further spread. Trees have the ability to attract tiny particulate matter from the air. A hectare of spruce forest attracts 30 tons of dust per year, pine forest - 37 tons. Forests perform a sanitary and hygienic role, releasing phytoncides that have an antimicrobial, sterilizing effect on the environment.
4. Work from the textbook (p. 171)
Students work according to the instructions in the textbook.
5. Physical education minute
V. GENERALIZATION AND SYSTEMATIZATION OF OBTAINED KNOWLEDGE
1. Did you know?
A hectare of forest releases 3-4 tons of oxygen and absorbs 4-5 tons of carbon dioxide, and is capable of filtering 50-70 tons of dust.
The forest is the lungs of the planet, as well as valuable resource, which brings money. This is why up to 20 hectares of forest disappear every day in the world.
2. Work in pairs
Complete and continue the sentences.
Forests are called... planets. Because they are the ones who clean the air from... gas and release...
3. Working on riddles
Black in winter, green in spring and summer, and yellow in autumn. (Forest)
Who undresses for winter and dresses for summer? (deciduous trees)
It sleeps in winter and makes noise in summer. (Tree)
Nobody scares her, but she always trembles. (Aspen)
In winter - like summer, in summer - like winter. (Spruce and pine)
Swinging on a tree
The spiny zhupan has,
Dressing for summer
And in the fall it sheds. (Chestnut)
They quickly ran up the mountain
Two white-haired girlfriends.
The rain rinses their braids.
The names of these girlfriends are... (birch trees).
In the middle of summer there is a snowstorm:
The fluff flies and spreads. (Poplar)
It grows in spring, blooms in summer,
In autumn it crumbles,
In winter he sleeps;
Treats the flu
I cough and wheeze. (Linden)
Summer and winter outfits friend,
And the kids always call me,
So that I can come to them for a holiday,
She brought them a lot of toys. (Christmas tree)
Both summer and winter
We have one outfit
Can he see us?
It’s been a year since I started with you. (Spruce and pine)
4. Literary moment
1) Reading the poem “Two Boys” by V. Brovchenko.
Two boys in the green season
We reached the forest - centuries-old oak groves.
One of them rolled his eyes instantly
And he busily wondered: “How much firewood!”
And all around it was chirping and blooming,
As a hundred centuries ago, so now...
Without streaming, the second boy: “How much light!”
He spoke and, excited, froze.
Two boys... And the forest is so intently in the eyes
I watched the smoke pipes for the neighbors.
He still didn’t know who the forester would be here:
Or the gardener of life, the woodcutter...
2) Reading the story by V. Sukhomlinsky “Sergei and Matvey.”
SERGEY AND MATVEY
Two young men, Sergei and Matvey, came to a flowering meadow.
What a beauty! - Sergei whispered. - Look, on the green carpet it’s as if someone has woven pink, red, white, blue flowers.
“It really is an exemplary grass,” said Matvey, “let a cow come here and by the evening there will be two buckets of milk.”
And the bees ring like a harp,” Sergei whispered, captivated by the magical music.
And if only we could bring the hives here... Honey, honey, how much honey the bees would bring,” Matvey said excitedly.
And there are people who don’t see this beauty,” Sergei whispered.
And there are such people. And over the years, such a misunderstanding of beauty can turn into a big disaster for nature. I hope that science lessons will help ensure that there are as few of these “Matveevs” among you as possible.
5. Ecological conversation
These are the lungs of the planet. Under human pressure, forests are retreating on all continents, in almost all countries. They are cut down faster than they grow. But it is the forest that actively cleanses the Earth’s atmosphere of pollution. Green plants absorb carbon dioxide, using it as building material for your cells. Each cubic meter of wood is almost half a ton of carbon dioxide removed from the air. Now the trouble-free “lungs” of cities in many regions of the planet require not just care, but are crying out for help and salvation. It should be noted that in Lately forest for overload with vacationers, their barbaric attitude towards nature, extermination of rare medicinal plants, berries, mushrooms, cutting down trees, fires caused by people lose their healing properties. It cannot withstand the influx of people in densely populated regions, it suffers and dies from industrial pollution, as well as as a result of the activities of oil workers, construction workers, and miners. It is estimated that at current rates of logging, even in forest-rich countries it will last for 50-60 years (recovery will take 100-200 years).
Children, we have come to the final question of our lesson - “Protection and conservation of forests.” In my opinion, this is the most main question. Because nature is the greatest wealth of any country. Why do you think? (Because she gives us session gifts that we cannot live without.)
What kind of payment does Mother Nature ask from us for this? (No, just that they be kind to her, take care of her and protect her.)
Do we, as rational beings, as patriots, citizens of our country, residents of the most beautiful planet, always protect and honor nature and fulfill our duties? (No not always.)
Therefore, I propose to warn our friends from the planet Ria so that they do not repeat our mistakes. After all, we, earthlings, could not preserve everything that nature gave us. Every year there are fewer and fewer untouched corners of nature left on Earth.
VI. SUMMARIZING. REFLECTION
Can you prove to anyone that forests are the real lungs of our planet, helping all living things breathe?
But whether the future of our planet will be happy and environmentally friendly depends largely on you. Think about this so that you don’t have to send us encryption messages asking for help.
VII. HOMEWORK