Plants are called the lungs of the planet because they are... The lungs of our planet. How photosynthesis was discovered

Introduction

Forest is a special wealth of any country. It's beautiful, recoverable natural complex, on which the entire ecosystem often rests.

The term “forest management” usually refers to the use of all forest resources, all types forest resources.

Several adverse effects can be identified that have a detrimental effect on the forest. The first unfavorable factor is the cutting of wood. Usually, a cut is usually called the moment when a more trees than what grows in a year, but sometimes this is not the most important factor critical attitude towards the forest. The fact is that in most cases, when cutting down, good, strong trees are taken away, leaving sick ones, and this in turn leads to even greater environmental harm. When logging is lagging behind in terms of wood growth, a second unfavorable factor is observed - undercutting, which, in particular, leads to aging of the forest, a decrease in its productivity, and diseases of old trees. Therefore, like overcutting, it leads to exhaustion forest resources and undercutting leads to underutilization of forestry.

For now, deforestation prevails on the planet. Emergence environmental problems may be associated not only with the scale of forest felling, but also with the methods of felling. Today, selective logging, although a more expensive form, is characterized by significantly less environmental damage. The regeneration of forest areas should take at least 80-100 years. Along with the problems of reforestation, which can be carried out through self-regeneration of forest plantations and, for acceleration, through the creation of forest plantations, the problem of careful use of harvested wood arises. Deforestation must be countered by the desire for the full use of wood, the use of gentle methods of logging, as well as constructive activities - reforestation.

Global ecological disaster in forestry

The state of forests in the world cannot be considered favorable. Forests are being intensively cut down and are not always restored. The annual felling volume is more than 4.5 billion m3.

To date, about 160 million hectares have been degraded tropical forests, and of the 11 million hectares cut down annually, only a tenth is restored by plantations. These facts are very disturbing global community. Rainforest covering 7% earth's surface in areas close to the equator, they are often called the lungs of our planet. Their role in enriching the atmosphere with oxygen and absorbing carbon dioxide is exceptionally great. Tropical forests are home to 3–4 million species of living organisms. 80% of insect species live here, 2/3 grow known species plants. These forests supply 1/4 of the oxygen reserves. For rational use All forests are divided into three groups.

First group . Forests with great importance in water protection and soil protection, green areas of resorts, cities and other settlements, protected forests, protective strips along rivers, highways and railways, steppe pegs, band burs Western Siberia, tundra and subalpine forests, natural monuments and some others.

Second group . Plantations of a sparsely wooded zone, located mainly in the central and western regions of the country, having protective and limited operational significance. Third group. Production forests of multi-forest zones of the country - regions of the European North, the Urals, Siberia, and Far East.

Third group . This group includes the industrial felling regime. It is the main base for timber harvesting.

The forests of the first group are not used, they are only cut for sanitary purposes, rejuvenation, care, lightening, etc. In the second group, the felling regime is limited, use is in the amount of forest growth.

The importance of forests in the formation of the biosphere

A review of the literature and the author’s logical constructions show that in life cycle of an individual tree and their totality, the amount of oxygen that is released by their living mass due to photosynthesis exactly corresponds to the amount of oxygen that is consumed by the plant for respiration during life and for its decay after death.

With the complete destruction of the planet's forests, the oxygen concentration, in accordance with the author's calculations, will decrease by 0.001%.

Atmospheric oxygen – necessary condition preservation of many forms of life on Earth, in particular humanity. At the same time, ever-increasing flows of fuel involved in the combustion process (oil, gas, coal, etc.) increase the alarmist sentiments of a certain part of the planet’s population, fueled by emotional publications of the media. mass media and some specialized publications. For example, there is a well-known point of view according to which the consumption of oxygen is an order of magnitude higher than its supply, amounting to 1.16·1010 and 1.55·109 t/year, respectively.

According to many, the trend towards a decrease in the amount of oxygen in the atmosphere is all the more dangerous because it develops against the backdrop of a reduction in the forest cover of the planet. It originally made up 75% of its surface, but has now fallen to less than 27%. The area of ​​tropical forests is declining especially rapidly, amounting to 0.95 billion hectares, or 56% of the total forest area. Of these, 11 million are cut down annually, and only 1 million hectares are restored.

On this basis, it is concluded that humanity is worsening the conditions of its existence, since vegetation, and above all the huge mass of forests, is a powerful source of oxygen production through the reaction of photosynthesis:

6 CO2 + 6 H2O + 2822 kJ 6 C6H12O6 + 6 O2 – chlorophyll light.

Since the positive role of forests in O2 production is usually not questioned, it is believed that measures to stimulate international community those countries on whose territory the “lungs” of the planet are located. One of them is the tropical forests of the river basin. The Amazon (Brazil), another – the vast forests of Russia, primarily Siberian. The number of articles on the topic “Russia – the lungs of the planet” is impossible to list. Let us point out only the last two in one of the issues of the magazine, which claims to be a leader in ecology and environmental management:

“Russia, which has large forested areas where carbon dioxide is converted into plant fiber carbon and free oxygen, should have preferential quotas to reduce CO2 emissions”; “It seems appropriate that oxygen producing countries should receive payment for it and use these funds to maintain forest areas».

It is noted that within the framework of the UN, proposals from “low-forest” countries (Germany, etc.) to preserve and increase Russian forests in the interests of the entire planet are being considered. And regarding tropical forests, a similar agreement was adopted in the early 90s. Developed Nordic countries pledged to pay developing countries African countries a kind of bonus of 10 dollars for every ton of carbon dioxide converted into oxygen. And such payments began in 1996. “It has been calculated,” continues V.M. Garin and co-authors, “that one hectare of forest absorbs about 8 liters of carbon dioxide per hour (the same volume is released when two hundred people breathe during the same time).”

At the same time, such widespread alarmist expectations are not confirmed by data from fundamental science.

Thus, fears about a possible decrease in the amount of atmospheric oxygen due to increased combustion of fossil carbon are not justified. It is estimated that the simultaneous use of all deposits of coal, oil and natural gas will reduce the average oxygen content in the air from 20.95 to 20.80%. Comparison with the most accurate analyzes from 1910 shows that, within the limits of measurement error, there was no change in atmospheric oxygen by 1980.

The disappearance of oxygen in the hydrosphere even when most of it is discharged into it modern waste also not dangerous. From Broker’s calculations it follows that with a planetary population of ten billion (about 1.7 times more than now), the annual discharge into the sea of ​​100 kg of dry organic waste per inhabitant (significantly higher than the current norm) will require about 2500 years to consume it all oxygen reserves of the hydrosphere. This is longer than the duration of its resumption.

Broker concludes that the amount of O2 in the atmosphere is not limited in comparison with human requirements for it and that an almost similar picture is observed for the hydrosphere. He writes: “if the existence of the human race is seriously threatened by the danger of environmental pollution, then it will more likely die for some other reason than due to lack of oxygen” (quoted in).

The role of forests in improving the atmosphere (absorption of CO2 and production of oxygen) is also not as clear as it seems to alarmists. The spread of emotional points of view is a consequence of an unprofessional assessment of the impact of forests on the environment. Let us note the features of the problem, which are usually not noticed intentionally or consciously in such cases.

Yes, indeed, the reaction of photosynthesis is indisputable. But the opposite reaction is also undeniable, manifesting itself in the process of respiration of living organisms and during the decay (oxidation) of mortmass (soil respiration). Therefore, at present in nature there is a stable balance between the amount of oxygen formed during photosynthesis and absorbed during the respiration of living organisms and soil (rotting)

After the death of the plant due to decay of the mortmass, the very complex structure of organic matter turns into simple connections such as CO2, H2O, N2, etc. The source of mortmass oxidation is oxygen produced in excess of what is necessary for plant respiration. At the same stage it is released and enters environment CO2 previously bound during photosynthesis. In other words, after the death of an organism, all of its carbon is oxidized again, binding the amount of oxygen, which is the difference between its mass released during photosynthesis and used for plant respiration during their life.

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 is of 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, which operate on a zero oxygen balance. These are the 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 a 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, real peat bogs there are not so many 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 enormous amounts of 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.

“Planets of the solar system” - Venus. Venus is the third brightest object in the Earth's sky after the Sun and Moon. Take care of our planet!!! Plan. The second planet of the solar system. Earth. Over time, water and an atmosphere appeared on planet Earth, but one thing was missing - life. A new star is born - our SUN. Saturn is the second largest planet in solar system after Jupiter.

“Lesson of the Planets of the Solar System” - Cultivate camaraderie, the ability to work in a group. Lesson information card. Physical education minute. Earth. Mars. PhotoForum. The role of the Sun for life on Earth. Star or planet. Lesson plan. Complete the tasks: Complete the test. Develop cognitive processes, computer literacy skills. Planets of the Solar System.

“Minor Planets” - Figure of Venus. Surface of the Moon. The distance from Venus to Earth varies from 38 to 258 million km. There is every reason to believe that there is a lot of water on Mars. Atmosphere and water on Mars. The volume of Mercury is 17.8 times less than that of the Earth. Composition and internal structure Mars. Physical fields of the Moon. The density at the center of the Earth is about 12.5 g/cm3.

“Planets in the Solar System” - Astronomical models of Ptolemy and Copernicus. Mars is the fourth planet from the Sun. The planet that was discovered “at the tip of a pen.” Neptune has magnetic field. Sun. Uranus has 18 satellites discovered. Mars. Neptune is the eighth planet from the Sun. A planet where life exists. Uranus. Neptune. The sun is a hot ball - the most nearby star to Earth.

“Ecology of the Planet” - Formalization of ecology into an independent branch of knowledge. Stages of interaction between human society and nature. Abiotic factors aquatic environment. Biological capacity of the environment. Age structure. Categories of living matter in the biosphere. Abiotic factors of the terrestrial environment. Systemic laws of ecology. Laws of ecology B. Commoner.

“Planets and their satellites” - The inner 10 moons are small in size. A huge number of craters have been discovered on the surface of Titania. Iapetus. Quite rightly, Pluto is called a double planet. The Eratosthenes crater with a diameter of 61 km was formed relatively recently. Therefore, the Moon either has no or very little iron core. From one upper climax to the next, 130 hours pass - more than five days.

Probably everyone has heard the expression “Forests are the lungs of our planet.” Forests occupy about 1/3 of the land area; the forest area on Earth is 38 million km². TO beginning of XXI century, humans destroyed about 50% of the forest areas that previously existed on the planet.

Let's take a walk through the forests and look at different trees all over the world, from Madagascar to Poland, from Scotland to Hong Kong.

1. The very first land plants were discovered in Australia. Their age is approximately 395 million years. About 370 million years ago (the beginning of the Devonian period), vegetation of low shrubby forms became widespread on land. And the very first forests were low-growing forests of giant horsetails and club mosses, more than 7.5 m in height.

South Sumatra, Indonesia. (Photo by Beawiharta | Reuters):

2. About 345 million years ago it began Carboniferous period, during which dense, extensive forests of giant horsetails and tree ferns, some 30 m in height, spread over the land.

Pitlochry, Scotland. (Photo by Jeff J Mitchell):

3. This rare tree with the fabulous name “Dragon's Blood” (Dracaena Cinnabari) is very interesting. It got its name from the red resinous juice it exudes. Dracaena vermilion is endemic to Socotra Island.

An old Indian legend says that a long time ago, in the Arabian Sea on the island of Socotra, there lived a bloodthirsty dragon who attacked elephants and drank their blood. But one day one old and strong elephant fell on the dragon and crushed it. Their blood mixed and wet the ground around them. Trees called dracaenas grew in this place. (Photo by Khaled Abdullah Ali Al Mahdi | Reuters):

4. About 225 million years ago, the era of dinosaurs began - Mesozoic era. In the Triassic and Jurassic periods the main tree stand was formed by cycads and coniferous trees(many redwoods), spread a large number of ginkgo

North Carolina, USA. (Photo by Jonathan Drake | Reuters):

5. At the beginning of the Paleogene period, during the Paleocene era, the climate continued to remain warm and humid, which contributed to the diversity of flora and abundance of vegetation, including angiosperms woody plants. The forests of the Northern Hemisphere were similar to modern forests tropical and temperate zones.

An interesting composition: stone crosses marking the graves of German soldiers at the German War Cemetery in Hoglede, Belgium, are being absorbed by nature over time. Crosses are not a hindrance for the development of a powerful tree. (Photo by Christopher Furlong):

6. And this bush is not hindered by several thousand tons of used tires in a landfill in France. (Photo by Eric Cabanis):

7. In general, as soon as a person finishes his activity, nature immediately takes its toll, growing through anything. (Photo by David Goldman):

8. By the way, half of the forest zone of the Earth. belongs tropical forests. (Photo):

9. At the end Cenozoic period, which began 66 million years ago and featured a wide variety of land, sea and flying animals, conifers began to dominate. Quaternary period, which ended the Cenozoic era, began approximately 1.8 million years ago and continues now. The alternation of eras of extensive continental glaciations and warm interglacial eras led to the extinction of many species of trees and other plants.

By the way, this is the Tunnel of Love - a natural monument of local importance. It is located near the village of Klevan, in the Rivne district of the Rivne region of Ukraine.

10. Hong Kong. Bricks are not a hindrance to this tree and its roots. (Photo by Clément Bucco-Lechat):

11. The site near Marlborough in southern England is one of the most spectacular places in Britain to see bluebells in spring. (Photo by Toby Melville | Reuters):

12. Over the past 8,000 years, humans have completely cleared about 50% of the forest areas that existed on the planet; these areas are occupied by crops, pastures, settlements, wastelands and other anthropogenic landscapes; of the remaining forests, only 22% consist of natural ecosystems. Moreover, more than 75% of forest destruction occurred in the 20th century.

Snow in Antrim, Northern Ireland. (Photo by Charles McQuillan):

13. Beautiful leaf fall in Shaanxi province, China. (Reuters Photo):

14. Another “capture” of territory by nature is a magnificent tree in Guadeloupe. (Photo by Nicolas Derne):

15. This is what the road to the house should look like. Louisiana mansion and oak alley. (Photo by Tim Graham):

16. This tree has been voted one of the most terrifying trees in Britain. It's like mucus is dripping from his mouth. The tree is located near a nursing home. One of the workers says that his children, after seeing this tree, could not sleep peacefully for a week. (Photo by David Garnham):

17. We are all accustomed to a slightly different view of the Great Wall of China. But in reality, in many areas it looks like this. Instead of millions of tourists in many places, the Walls are trees. (Photo by Damir Sagolj | Reuters):

18. And it’s snowing again in Minnesota. Like in the TV series Fargo. (Photo by Scott Olson):

19. It is difficult to convey the impressions of visiting such grandiose places as the Cambodian temple complex. A special place here is the Ta Prohm Temple, where huge trees, reminiscent of centuries-old sequoias or oaks, merge with walls and towers and hug the stones with giant roots. (Photo by Lucas Schifres):

20. This is what the forest looks like after forest fires. Location south of Santiago, Chile. (Photo by Martin Bernetti):

21. A few years ago in Pakistan there was a massive invasion of spiders, thanks to which you can observe an unprecedented spectacle: they covered roadside trees so thickly with their web that they are barely visible under the accumulation of the finest threads.

The reason for this was the most catastrophic flood in the last 80 years, which affected the lives of millions of people and caused long-term flooding of most of the country. (Photo by Russell Watkins):

22. Well, a very unusual tree trunk in Guangxi, China. Like a web.

23. There is a legend about the unusual appearance of this tree in Africa. One day there was a disagreement between God and the baobab tree. Angry with the tree, God tore it out of the ground and stuck it back upside down. Read more: “Baobab is a tree that grows upside down.” (Photo by Anthony Asael):

24. Buddha's head intertwined with the roots of a tree in the ruins ancient city Ayutthaya, Thailand. (Photo by Jorge Silva | Reuters):