Why are earthworms called earthworms. Earthworms play an important role in creating fertile soils. Ecopark Z. All of the above seems to indicate that the flooding of soils with water cannot be of particular importance for worms and that these animals

earth, or earthworms (lat. Lumbricina) - a suborder of small bristle worms from the order Haplotaxida. They live on all continents except Antarctica, however, only a few species initially had a wide range: the distribution of a number of representatives occurred due to human introduction. The most famous European earthworms belong to the Lumbricidae family.

scientific classification

Kingdom: Animals

Type: Annelids

Class: Belt worms

Subclass: Small-bristle worms

Order: Haplotaxida

Suborder: Earthworms

families

• Acanthodrilidae
• Criodrilidae
• Eudrilidae
• Glossoscolecidae
• Lumbricidae
• Megascolecidae

Structure

Representative body length different types varies from 2 cm (genus Dichogaster) to 3 m (Megascolides australis). The number of segments is also variable: from 80 to 300. When moving, earthworms rely on short setae located on each segment except the anterior one. The number of setae varies from 8 to several tens (in some tropical species).

The circulatory system of worms is closed, well developed, the blood is red. Breathing is carried out through the skin rich in sensitive cells, which is covered with protective mucus. The nervous system of earthworms consists of a poorly developed brain (two nerve nodes) and an abdominal chain. Have developed ability to regeneration.

Earthworms are hermaphrodites, each sexually mature individual has a female and male reproductive system (synchronous hermaphroditism). They reproduce sexually using cross fertilization. Reproduction occurs through cocoons, inside which the eggs are fertilized and develop. The cocoon occupies several anterior segments of the worm, standing out from the rest of the body. The exit from the cocoon of small worms occurs after 2-4 weeks, and after 3-4 months they grow to the size of adults.

Applied value

The importance of earthworms in the process of soil formation was one of the first to be pointed out by Charles Darwin in 1882. Earthworms create minks in the soil (at least 60-80 cm deep, large species- up to 8 m), contributing to its aeration, moistening and mixing. The worms move through the soil by pushing particles apart or swallowing them.

After the rains, earthworms come to the surface due to a lack of oxygen, which is why they got one of their names - earthworms.

Breeding earthworms

Breeding earthworms (vermiculture) allows you to process various types of organic waste into high-quality environmentally friendly fertilizer - vermicompost. In addition, due to the fertility of worms, it is possible to increase their biomass for use as feed additives to the diet of farm animals and poultry.

For breeding worms, compost is prepared from various organic wastes: manure, chicken manure, straw, sawdust, fallen leaves, weeds, tree branches and bushes, processing industry waste, vegetable stores, etc. After the environmental conditions in the compost lead to optimal conditions, the worms are settled in the compost. After 2-3 months, a sample of the multiplied worms is made from the resulting biohumus.

If you do not know why the earthworm belongs to the annelids, then in our article you will find answers to your questions.

Why is the earthworm so called?

annelids- a type of highly organized worms (worms), which includes about 15 thousand species.

So why the earthworm belongs to the annelids, here is the answer: worms of this type bilateral symmetry is inherent, their body is divided into separate rings, they are called "segments". Segments - a part of the body of animals that are located throughout the body in a certain order one after another. It is through this that the earthworm is called annelids and attributed to the type annelids.

What is adaptation earthworm to life in the soil? Adaptability is manifested in the fact that worms play an important role in the formation of soil and increasing its fertility. Earthworms improve how chemical composition, and physical properties land, for example, by their activity they increase aeration (the process of gas exchange between soil and air), improve porosity, water permeability, moisture capacity, and the like. They enrich bottom layer soil with fertilizer, which is formed in their intestines as a result of the digestion of food. They ensure soil fertility.

Interesting historical facts about annelids:

1) They were called "sacred" by Queen Cleopatra;

2) Aristotle called them the intestines of the earth”;

3) Charles Darwin believed that they are an integral part of our lives and occupy their rightful place in world history and the like.

Valentina Fomina
Information and research project "Why do we need earthworms?"

Introduction

Once in the kindergarten, the teacher Valentina Vyacheslavovna read a fairy tale about earthworms. We are interested question: « Why do we need earthworms?» . And we noticed that in wet weather, after rain they appear on the surface of the earth, and the rest of the time they are in the soil. That is why they are called rain? The tale said that earthworms are very useful. Is it really?

the main objective project Why do we need earthworms?

figure out the meaning earthworms.

Tasks:

Experiment to test the proposed hypothesis.

Get an idea about earthworms

Learn to take good care of earthworms.

Hypothesis:

1. Worms benefit or worms are damaging.

Program practical action in implementation Topics:

1. Determination of the topic, purpose, tasks

2. Collection of material: (scientific literature; magazines, newspapers, articles; information on the Internet; scientific documentary)

3. Study of the collected information, experience

4. Conclusions from information

5. Speech to kindergarten students and teachers

6. Registration of work

7. Protection project in kindergarten

8. Dissemination of results

1. Main body

From the encyclopedia and the Internet learned:

The earthworm is called"Night Crawl". It turns out that on the surface of the soil worms crawl out at dusk and at night, and during the day - only after rain.

Latin name worms means - vermes. Really. Worms very similar to vermicelli. Therefore, the science of earthworms and called vermicology. Worms- These are large invertebrate soil animals that feed on plant debris. earthworms- these are continuously operating mini-factories for the production of humus (soil organic matter).

The earthworm has an elongated, 1 - 2 cm long, on average 10 -16 cm body, but sometimes up to 3 meters. Unlike round worms, whole body earthworm divided by annular constrictions into 100-180 segments. Each segment has small bristles. With these bristles worm clings when driving for uneven ground.

Valentina Vyacheslavovna brought to the group earthworms. We took worm in hand, and found that his skin was moist, covered with mucus. This mucus makes it easier to move worm in the soil. In addition, penetration into the body occurs only through moist skin. oxygen worm needed for breathing. Earthworms do not breathe air, but skin. Cells accumulate air, then give it to all organs. During rain water fills the passages earthworms underground. In order not to suffocate, they have to crawl to the surface. That's why they're called that... earthworms. They crawl out onto the asphalt because it is warmer there than on the surface of the earth. Birds do not peck on the road.

On the Internet, we found a very interesting educational cartoon "Journey earthworm» . From it we learned about life earthworms, their nutrition and reproduction.

In the encyclopedia, we examined the structure and appearance worms.

Such nondescript and small animals have a complex internal structure. Worms have a heart, blood vessels, stomach, intestines and other internal organs.

Muscles fused with it are located under the skin. Circular muscles make the body worm thin and long, and the longitudinal ones shorten and thicken it. Thanks to the alternating work of these muscles, movement occurs. worm.

Experiment 1

We took a transparent container, filled it layers: 1st layer - earth, 2nd layer - sand, 3rd layer - earth. There was a clear boundary between the layers. Then placed there worms. The earth was periodically sprinkled with water. The border disappeared after 1.5 months "sand - earth".

The result was a homogeneous mass.

Based on the experimental data, we can conclude that penetrating the soil with passages, earthworms loosen it, promote aeration and moisture at depth, mix the soil layers and thus increase soil fertility. Our experiment took place in winter time so we fed tea waste worms, since the withered foliage was not found.

The hypothesis was confirmed.

Experiment 2

After analyzing the condition of indoor plants, the teacher and I chose a drooping nephrolepis plant and placed it in the ground obtained as a result of 1 experiment. After a while, we noticed that the plant began to grow better. The branches have become stronger, the bush is more magnificent, the color is saturated. Conclusion: earthworms improved the structure of the earth.

The hypothesis was confirmed.

Experiment 3

Find out if you need worms in potted houseplants.

The teacher and I placed earthworms in a pot and planted a flower. After 2 weeks, they noticed that the flower began to fade. We carefully took the flower out of the pot and carefully examined root system. We found that worms ate the roots of a flower.

Conclusion: Worms in pots of indoor flowers needed.

By the way, useful information: to delete worm from a pot, you can lower the pot into the water and worms will crawl to the surface on their own.

The hypothesis was confirmed.

earthworms are very numerous in the soil, and their activity is of great importance in soil-forming processes.

Roaring in the ground worms loosen the soil and thereby open access to air and water, necessary for the complete decomposition of organic matter. They drag rotten leaves and other plant and animal remains inside their underground passages and thereby contribute to the enrichment of the soil with humus, and, rummaging in the depths, pass the earth through their intestines, mix the soil and increase the thickness of its fertile layer. On loosened, mixed and enriched with humus soil, vegetation flourishes. But worms can eat plant roots. That's why indoor plants they are not needed, and you can use the soil after processing worms. But it is assumed that in the near future worms will become one of the popular culinary dishes.

In conclusion, we would like to conclude that earthworms These are amazing animals!

We told and showed our project, in other groups, at the parent meeting and in your group. We also want to invite you to get to know our project committee of municipal economy, we think that our project will help improve the greening of our city.

List of used literature:

1. Zenkevich L. A. Life of invertebrate animals, part I, Moscow, 1968;

2. Iogonin A. M. Earthworms Kovrov 2002;

3. http://animalregister.net

4. http://sng-portal.ru/arhiv/podkormka-rasteniy/chem-polezny-dozhdevye-chervi/

5. http://atcm.pp.ua/foto-zemlyanoj-chervyak.html

6. http://knu.znate.ru/docs/index-568659.html

Annex 1

earthworm

Once upon a time there was a brother and sister - Volodya and Natasha. Volodya, although younger than his sister, is bolder. And Natasha is such a coward! Total was afraid: mice, frogs, worms and cross spider who weaved his web in the attic.

In the summer, children were playing hide-and-seek near the house, when suddenly the sky darkened, frowned, lightning flashed, large heavy drops first fell to the ground, and then poured torrential rain.

Children hid from rain on the veranda and began to watch how foamy streams ran along the paths, large air bubbles jumped through the puddles, and the wet leaves became even brighter and greener.

Soon the rain subsided, the sky brightened, the sun came out, and hundreds of small rainbows began to play in raindrops.

The children put on rubber boots and went for a walk. They ran through the puddles, and when they touched the wet branches of trees, they brought down a whole waterfall of sparkling jets on each other.

The garden smelled strongly of dill. They crawled out onto the soft wet black earth earthworms. After all rain flooded their underground houses, and worms they became damp and uncomfortable.

Volodya lifted worm, put it in the palm of your hand and began to examine, and then wanted to show worm sister. But she recoiled in fear and screamed:

Volodya! Drop this crap right now! How can you take worms in hand, they are so nasty - slippery, cold, wet.

The girl burst into tears and ran home.

Volodya did not at all want to offend or frighten his sister, he threw worm to the ground and ran after Natasha.

earthworm Vermi's name became painful and insulting.

"What stupid kids! Vermi thought. “They don’t even realize how much good we bring to their garden.”

Grumbling with displeasure, Vermi crawled to the garden with zucchini, where under the large fleecy leaves they were going to chat earthworms from all over the garden.

What are you so excited about, Vermi? his friends asked solicitously.

You can't even imagine how the children offended me! You work, you try, you loosen the earth - and no gratitude!

Vermi talked about how Natasha called him nasty and nasty.

What ingratitude! - were indignant earthworms. - After all, we not only loosen and fertilize the earth, but through the dug by us underground passages water and air enter the roots of plants. Without us, plants will grow worse, and may even dry out completely.

Let's all crawl away to the neighboring garden together. A real gardener lives there, Uncle Pasha, he knows the price for us and will not give us offense!

Worms dug underground tunnels and through them got into a neighboring garden.

At first, people did not notice the absence worms, but the flowers in the flower bed and the vegetables in the beds felt the trouble immediately. Their roots began to suffocate without air, and the stems began to wither without water.

I don't understand what happened to my garden? sighed Paul's grandmother. The earth has become too hard, all the plants are drying up.

At the end of the summer, dad began to dig up the garden and noticed with surprise that there was not a single one in the clods of black soil. earthworm.

Where did our underground helpers go? he thought sadly, maybe earthworms crawled to the neighbors?

Dad why did you call worm assistants are they useful? Natasha was surprised.

Of course useful! Through dug earthworms passages to the roots of flowers and herbs get air and water. They make the soil soft and fertile!

Dad went to consult with the gardener Uncle Pasha and brought from him a huge clod of black soil in which they lived earthworms. Vermi and his friends returned to Grandma Paulie's garden and began to help her grow plants. Natasha and Volodya began to relate to earthworms carefully and respectfully, and Vermi and his comrades forgot past grievances.

Annex 2 (presentation)

Koval Alexander, 4th grade student of MBOU "Tashlin secondary comprehensive school”, Orenburg region Tulgansky district with. Tashla. The work was carried out under the guidance of the teacher Litvinenko Olga Anatolyevna.
Material Description: Development can be useful as teachers primary school and biology teachers.
Subject. Dungeon dweller - earthworm.
Table of contents
Introduction ................................................ ...................................................3
Chapter 1. Theoretical part............................................... ...............4
1.1 Who are earthworms? .............................................. ..............4
1.2 The life of earthworms.................................................... .................5
1.3 Benefits of worms............................................... .................................6
1.4 Why do earthworms come to the surface after
rain................................................................ ...............................................7
1.5 Interesting Facts from the life of worms ............……………...…..8
1.6 Use in alternative medicine....................................................10

Chapter 2. Practical part............................................... ..............10
2.1 Questionnaire.................................................... ............................10
2.2 Experiment.............................................. ................................12
2.3 Interviewing.................................................... .....................12
Conclusion................................................. .........................................13
Bibliography................................................. .....................................14
Applications ................................................. ........................................15
Appendix 1……………………………………………………..15
Appendix 2……………………………………………………..15
Annex 3……………………………………………………..18

Introduction
Many of us have seen how earthworms crawl en masse to the surface of the earth during rain, but few people know why they do it. However, scientists have a lot of interesting hypotheses. Some believe that the craving for travel drives the worms to the surface, while others believe that the reason for this behavior is the fear of moles. There are those who consider both these hypotheses to be true.
For a successful struggle to increase productivity, all the forces of nature related to plant life must be fully taken into account and used.
One of these forces is the activity of soil animals. Until recently, its significance for soil formation was underestimated, despite the fact that the basic facts in this area were established long ago.
Among the soil fauna, earthworms occupy a prominent place.
Relevance of research work. Many do not pay attention to the worms, and many also try to crush them. Maybe because they don't like their appearance?
Earthworms do a colossal job of improving and improving the soil, they are "fighters of the invisible front", whose work is invisible, and therefore few appreciate the worms at their true worth.
How did the research topic come about?
In the spring, my classmates and I class teacher leaves were raked in the schoolyard and many worms were noticed. There was nowhere to go. Why so many worms? I wonder why they got out. I shared my observations with the teacher, and she suggested that I study earthworms.
object research work is an earthworm.
Subject research is the role and importance of the earthworm in nature.
aim work is to consider the behavior of the earthworm after rain.
To achieve this goal, I had a number of the following tasks:
1. Study the literature on this topic.
2. Clarify the idea of ​​the earthworm, its adaptation to life underground and follow the life of worms on the surface.
3. Find out why earthworms crawl to the surface after rain
4. Find out what role they play in our environment earthworms.
Various methods:
1. Studying the literature on this topic.
2. Collection of information on the Internet.
3. Questioning.
4. Interviewing.
5. Experiment.
Hypothesis.
I find worms useful. If it rains, then the worms underground become unable to breathe, and therefore they crawl out to the surface.
The research work was carried out in Tashla of the Tulgansky district in the summer-autumn period.

Chapter 1. Theoretical part
1.1 What are earthworms?
The word "worm" does not have a strict scientific value- this is usually called a variety of invertebrates with an elongated soft body.
Annelids originated from the common ancestors of worms under the influence of evolutionary factors. An important point in their evolution is the division of the body into segments (rings). In connection with the active movement of the annelids appeared circulatory system supplying the body nutrients and oxygen. Ancient annelids had a more complex structure compared to other worms.
1.2 The life of earthworms.
Soil moisture, temperature and amount of food are the main conditions necessary for the life and reproduction of worms. In dry weather, they burrow to a depth of 2 - 2.5 meters.
The earthworm lives in various soils, loosening and processing them (this activity is especially favorable on the soils of vegetable gardens and orchards). These animals, passing the soil through their intestines, constantly improve it, saturating it with organic residues and mixing, loosen it, providing air access to the deeper layers, and increase fertility. In some cases, the transfer of earthworms to soils where they were not previously present increases the yield of horticultural crops. In countries with a humid climate, earthworms are more numerous. However, in waterlogged soils, as well as in swamps, especially peat ones, the earthworm does not live.
They cannot live in sand.
During the day, the worm hides in a mink (a mink is a narrow long channel, which in hot summer can reach a depth of 1.5 meters, with an extension at the end for a turn) with its head towards the entrance, which is covered with leaves, pine needles and other garbage, and at dusk comes to life. It crawls out to the surface with almost its entire body, only the rear end clings to the edge of the mink, and the front part of the body makes circular motions, rising above the ground, and feeling everything around. He feels with his lips a fallen leaf of a tree, grabs it and drags it into his mink. Worms spend their whole lives in the ground, dig deep passages, and thus loosen the ground. But sometimes they are forced to leave their water-filled minks after heavy rains so as not to suffocate.
Worms feed on rotting leaves, swallowing lumps of earth, grains of sand. Worms breathe with the entire surface of thin delicate skin, penetrated by blood vessels.
It is precisely the peculiarity of breathing that makes earthworms leave their minks.
During the rain, remaining in them, the worm runs the risk of simply choking. Having waited for the end of the “flood”, vulnerable creatures again rush to take refuge in the thickness of the earth.
In winter, they curl up into a ball and sleep. When we see a worm on the surface, it means that it is looking for new house or more nutritious soil. Worms cannot live in sunlight.
Annelids living in the soil serve as food for many animals. They are eaten by moles, frogs and some reptiles.
1.3 The benefits of worms.
The earthworm can be called the most important animal in the world. Important, of course, from a human point of view, since the activity of these creatures prepares the ground for the growing season on which life depends.
In the forests and meadows, many withered, withered plants and animal remains are constantly accumulating. Something must be done with them! Here are earthworms and their work colleagues (snails and beetles) and play the role of scavengers and orderlies. They turn unnecessary residues and waste into the soil necessary for everyone, dig passages, loosen the earth. Water and air can easily pass through these passages to the roots of plants. On such land, grasses and trees grow better. So worms should be welcome guests in our gardens. The more of them there are, the richer the soil in the beds will become, and this will make the harvest better.
Earthworm fertilizer contains lime, which enriches the soil. The importance of this can be seen in one example. Scientists have discovered an area with one of the most fertile soils. They calculated that there are 108 tons of earthworm waste per half a hectare. That's why this area has been so fertile for hundreds of years!
1.4 Why do earthworms come to the surface after rain.
We asked a question on the Internet:
Why do earthworms come to the surface after rain?
And we got interesting answers.
First possible cause why earthworms crawl out after rain is the change in soil temperature they feel when it rains. Most earthworms live deep underground, thanks to warm temperature under layers of soil.
The second possible reason why earthworms crawl out after rain is due to changes in the pH level of the soil. Other experts also believe that some types of soil tend to receive higher concentrations of cadmium during rain.
The third possible answer to the question of why earthworms crawl out after rain is the variability that is phenotypic in nature. Perhaps there are some worms that cannot submerge in water for a long time.
The fourth reason why earthworms crawl out after rain is the fact that some worms need little air. Water saturates the surface of the earth with a large amount of oxygen.
The fifth reason why earthworms crawl out after rain is due to their natural behavior. Perhaps they crawl out after rain because most of them do that, and not because they need more or less oxygen.
Another possible reason why earthworms crawl out after rain is because they love moisture. Worms like to rise to the surface to enjoy the moisture on the ground.
And yet the most plausible version sounds like this:
The earthworm breathes on the entire surface of the body, which is covered with mucous, moist skin. Too little air is dissolved in the water, and therefore the earthworm suffocates there. Therefore, in rainy weather, it is much easier for worms to breathe on the surface of the earth.
After viewing the works, we found out: the worms are forced to leave their water-filled minks after heavy rains so as not to suffocate.
1.5 Interesting facts from the life of worms.
Earthworms - belong to the kingdom of invertebrates, suborder earthworms. The body of an earthworm consists of annular segments, the number of segments can reach up to 320. When moving, earthworms rely on short bristles that are located on the body segments. Earthworms are distributed throughout the planet, except for Antarctica.
Appearance of an earthworm. Adult earthworms are 15 - 30 cm in length. In the south of Ukraine, it can reach and large sizes. The body of the worm is smooth, slippery, has a cylindrical shape and consists of piece rings - segments. The ventral side of the body is flat, the dorsal side is convex and darker than the ventral side. Approximately where the front of the body ends, the worm has a thickening called a girdle. It contains special glands that secrete a sticky liquid. During reproduction, an egg cocoon is formed from it, inside which the eggs of the worm develop.
The earthworm moves by crawling. At the same time, it first draws in the anterior end of the body and clings with the bristles located on the ventral side to the unevenness of the soil, and then, contracting the muscles, pulls up the posterior end of the body. Moving underground, the worm makes its own passages in the soil. At the same time, he pushes the earth apart with the pointed end of the body and squeezes between its particles.
Moving in dense soil, the worm swallows the earth and passes it through the intestines. The worm usually swallows the earth at a considerable depth, and throws it out through the anus at its mink. So on the surface of the earth long "laces" of earth and lumps are formed, which can be seen in the summer on garden paths.
This method of movement is possible only in the presence of well-developed muscles. Compared to the hydra, the earthworm has more complex muscles. She lies under his skin. Muscles together with the skin form a continuous musculocutaneous sac.
The muscles of the earthworm are arranged in two layers. Beneath the skin lies a layer of circular muscles, and beneath them is a thicker layer of longitudinal muscles. Muscles are made up of long contractile fibers. With the contraction of the longitudinal muscles, the body of the worm becomes shorter and thicker. When the circular muscles contract, on the contrary, the body becomes thinner and longer. Contracting alternately, both layers of muscles cause the movement of the worm. Muscle contraction occurs under the influence nervous system branching in muscle tissue. The movement of the worm is greatly facilitated by the fact that there are small bristles on its body from the ventral side. They can be felt by running a finger dipped in water along the sides and along the ventral side of the worm's body, from the rear end to the front. With the help of these bristles, the earthworm moves underground.
On half a hectare of the garden, worms pass through their bodies about 16 tons of soil in 1 year.
There are so many earthworms in the soil that if we take them all, for example, from the United States, then their weight will be 10 times the weight of the population.
The earthworm does not have eyes, but it does have sensory cells on the surface of its body. This gives him the ability to distinguish light from darkness and feel subtle touches.
According to legend, St. Francis of Assisi collected and carried earthworms that he encountered on his way to a safe place so that they would not be crushed by travelers, in memory of the prophetic words related to Jesus Christ: “I am a worm, not a man”
1. 6 Application in alternative medicine.
It is often mentioned that a writhing worm was dragged around the child's neck to treat whooping cough or sore throat. If the fisherman happened to cut himself while fishing, he immediately grabbed a large sandworm from his can of bait, pressed it to the wound, and then threw it into the water. The cut was then washed with water. Behind all this was the belief that the worm would draw evil out of the wound, and water would cleanse it. It is possible that English beliefs about medicinal properties, attributed to worms, correlate with folk ideas about the healing properties of snakes.
IN Western Europe washed earthworms or powder from dried worms were put on wounds for their healing, tincture on the powder was used for tuberculosis and cancer, ear pain was treated with decoction, worms boiled in wine - jaundice, oil infused on worms - fought against rheumatism. The German physician Stahl (1734) prescribed dried worm powder for epilepsy. The powder was also used in Chinese traditional medicine as part of a drug to get rid of atherosclerosis. And in Russian folk medicine the liquid that has expired from salted and heated earthworms was instilled into the eyes with cataracts.
Chapter 2. Practical part
2.1 Questionnaire
In order to find out what students know about earthworms, a survey was conducted among primary school students (37 people in total).
The survey was conducted on the following questions.
1. Have you met earthworms? (Not really)
2. Where did you see them? (on beds, in manure, on roads)
3. Where do they live? (underground, in the garden, in manure)
4. Why are worms called earthworms? (they go outside when it rains, they love the rain, they are always wet)
5. Are these worms useful? (yes, no, don't know)
6. Why do worms crawl out to the surface after rain? (It’s hard for them to breathe underground, wash, swim, breathe fresh air)
In general, according to the results of the survey, it can be concluded that most of the students surveyed are familiar with the earthworm. Many students agreed with our hypothesis. Most of the respondents are not aware of the usefulness of earthworms.
2.2 Experiment
We dug up the worms and put them on paper. It turns out they move very well.
Then they collected earth into a transparent plastic cup and put the worm in it. After a while, the worm burrowed into the ground. After that, we began to splash water into a glass. The worm gradually began to crawl out to the surface of the soil. This means that the earthworm breathes the entire surface of the body, which is covered with mucous, moist skin. Too little air is dissolved in the water, and therefore the earthworm suffocates there. Therefore, in rainy weather, it is much easier for worms to breathe on the surface of the earth.
2.3 Interviewing
As part of this study, we interviewed a biology teacher Natalya Nikolaevna Kryuchkova. She said that the worms are called "the plow of the earth" because they began to loosen the earth before man. They are called "orderlies of the earth", because, passing the earth through their stomach, they save us from harmful microorganisms, and hence from diseases. They are called “living fertilizers” for plants because they enrich the soil with nutrients. So, they can be called "treasures living underground."
Natalya Nikolaevna also told us the theory about worms and why worms crawl out to the surface after rain. She offered us books about worms. (Annex 3)
After taking the interview, we came to the conclusion that our hypothesis is confirmed.
Conclusion
In our area, earthworms are quite common. I watched earthworms, read about them in books. Found stuff online. After studying the literature and doing research, I came to the conclusion that they are a treasure for plants, animals and humans. Earthworms are a valuable product, which, after a certain processing, is used as a feed additive in poultry and fish farming, as well as raw materials for the pharmaceutical industry.
And that's why they crawl out to the surface after the rain, now I know the exact answer.
And when it rains, we will just look under our feet so as not to crush them, because the worms play an important role. ecological role and need protection.
As you can see, the mystery of earthworms crawling to the surface during rain has not yet been fully solved. However, zoologists continue their research, and it is possible that in the near future there will be one less mystery in the field of applied zoology...
The knowledge gained during independent observations will help me and other students to understand the importance of the activity of earthworms in the process of soil formation, to apply their knowledge during practice at the school site.

Bibliography
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5. Visual dictionary Animals "Dorling Kindersley", London 2001. A series of visual dictionaries "
6. Teremov A., Rokhlov V. Entertaining zoology. A book for students, teachers and parents. - M.: AST - PRESS, 1999. -528 p.: ill. - ("Entertaining lessons")
7. "Fidget" children's magazine. No. 14 - 2012

Once, at a lesson on familiarization with the outside world, the teacher told us about the diversity of the animal world. I learned that the science of animals is called zoology and zoologists divide the animal kingdom into a large number of groups. Most of all I was interested in the group "Worms".

From the early childhood we saw earthworms and, only now I have a question about what they are for, what role they play in nature. The teacher suggested that I research work to study the role of earthworms in soil formation.

The purpose of the experiment is to place earthworms in four containers: in the first, the soil on which the remains of dry leaves and grass were placed on top; in the second, compacted soil; in the third, sand and soil are covered in layers; in the fourth dry leaves and grass. Wrap all containers in foil and hide in a dark place, after a certain amount of time open and look at the changes that have occurred.

The result of my work will be to find out what benefits earthworms bring in nature. I want to find out if these small, nondescript and even unpleasant-looking animals are needed, or if they have no meaning in nature.

All the questions that arose aroused great interest in me, and I decided to start research work.

I hope that the materials presented in my work will help the children understand the importance of simple, earthworms in the life of nature. Are there living beings in nature that have no meaning, and no one would notice their absence.

earthworms

All relatively large worms that live in the soil are called earthworms. Everyone is well aware of these creatures, which after rain can be seen on the ground, paths, in puddles.

Earthworms live in moist soils throughout the globe. The smallest of them are only 1-2 cm long, but some tropical species are real giants. Their three-meter body often terrifies tourists.

When moving, the earthworm alternately stretches out, then contracts, clinging with bristles to the unevenness of the soil. At the same time, special cells in its skin produce mucus that facilitates movement in the ground.

Worms breathe with the entire surface of the skin. Oxygen is carried with blood through two main vessels - dorsal and abdominal, which permeate the entire body.

Earthworms spend most of their lives underground, where they dig long, intricate passages.

The number of worms is enormous. On 1 hectare of their land total weight may be several tons. Worms waking up after hibernation, begin to lay cocoons (one cocoon about once a week) within three months. During the year, the number of earthworms increases more than a thousand times. In winter, some of the young worms may die.

Varieties of earthworms

The most common types of earthworms are:

1. The earthworm is tetrahedral. It is 3-5 cm long, its middle and rear parts are tetrahedral. Found only in very humid areas.

2. The foul-smelling earthworm is 6-13cm in length. It got its name for the specific unpleasant odor it emits. characteristic feature: red or brown rings. It is found mainly in manure heaps.

3. The yellowish green earthworm is 5-7 cm long. Its color can be different: yellowish, greenish, brown. Lives in both slightly moist and very damp soil.

4. The reddish earthworm is 7-15cm in length. The dorsal side is reddish-brown and purple with a pearly sheen. This is a typical inhabitant of more or less moist, humus soil, usually at shallow depths.

5. Earthworm terrestrial or ordinary (creeping out) is 9-30cm in length. It is very widely distributed, especially common in clay soils. On wet nights, it climbs to the soil surface for the remains of plants.

Tireless agricultural technicians

Charles Darwin was one of the first to appreciate the great importance of unattractive earthworms in the life of mankind. He devoted several years of hard work to their study.

Darwin found that earthworms pass through the entire arable layer of the earth in a few years. They enrich depleted lands with fresh humus, loosen them, simultaneously fertilizing with their secretions and leaves carried away into minks. The countless burrows of worms provide perfect drainage and soil ventilation.

The well-known Polish biologist Jan Dembowski draws attention to the presence of a kind of mental activity in earthworms.

I. Akushin, studying the mental activity of earthworms, proved their ability to learn. The worms were placed in a T-maze, in the longest corridor forming the base of the letter "T". When the worms crawled to its end, they were given the choice to turn right or left. “To the left” a blackout and food awaited them, “to the right” a blow electric currents. After several attempts, the worms learned to unmistakably go in the right direction - to food.

E. Yu. Ziborova found out that the absence of earthworms in the soil means that the soil conditions are unfavorable for their life activity, and, as a result, the fertility of such soil is extremely low. All earthworms lead the same way, night image life: they spend their whole lives in the ground, digging deep passages and thus loosening the ground, crawling out to the surface of the soil only at night. They are also forced to leave their water-filled burrows after heavy rains so as not to suffocate. The mink of the worm is a narrow long channel, which in hot summer can reach a depth of 1.5 meters, with an extension at the end for a turn.

Practical work

Part 1. The beginning of the experience.

All my work will consist of four experiments. I'll take four containers.

In the first place I will put earthworms and cover them with earth, from the top I will put small remains of leaves. I will wrap everything in foil and put it in a dark place for 5 days.

In the second, I will place earthworms on the bottom, cover them with earth and lightly tamp, draw a line indicating the level of the earth in the tank. I will wrap it in foil and put it in a dark place for 5 days.

In the third, I will place earthworms on the bottom and cover the sand and soil in layers. I will wrap it in foil and put it in a dark place for 10 days.

In the fourth container I will place earthworms and fill them with small dry leaves and blades of grass. I will wrap it in foil and put it in a dark place for 15 days.

I placed all the containers in a dark place to create conditions close to natural, for animals to live. For the same purpose, periodically the contents of the containers must be sprinkled with water, since earthworms live in moist soil, in the dark.

Part 2. Finding out the changes that have occurred in 5 days.

It's been 5 days and I can find out what changes happened in the first two containers. Taking out the first one, I found that the earthworms dragged all the dry leaves and blades of grass into their minks. It seems to me that for a small worm it is truly a feat - to transport under the ground a whole leaf weighing a little less than the worker himself. At first glance, nothing special happened, but, after thinking, we can conclude that with the help of these little workers the soil is fertilized, since the leaves in the ground rot faster and form the necessary fertilizers for better plant growth.

After analyzing the second container, I found that the soil had risen above the line drawn. What useful things did the worms do here for 5 days?

Conclusion. Earthworms loosened the soil, allowing more oxygen to penetrate into it, which, like humus, is necessary for better growth and development of plants. But the presence of oxygen is important not only for plants, but also for other animals living in the earth.

Already at the first stage of the ongoing experiments, it is clear what benefits these small, nondescript animals bring.

Part 3. Finding out the changes that have occurred in 10 days.

Taking out a container in which sand and soil were covered with layers, I found that they were mixed. What does this mean? What useful things did the worms do for 10 days?

Conclusion. Passing the earth through their intestines, the worms mix the layers of the soil, enriching it with humus.

After analyzing this part of the experience, I again became convinced that they were loosening the ground.

Part 4. Finding out the changes that have occurred in 15 days.

I found interesting changes in the fourth container. Soil formations appeared there. For 15 days, earthworms fed on decaying plant debris. Passing them through themselves, they processed them and formed the soil.

Conclusion. Earthworms are soil formers.

Chapter 5

After analyzing all the experiments, I came to the conclusion that earthworms, these tireless little workers, perform hard work by soil formation, loosen it and enrich it with fertilizers and oxygen. The more earthworms live on a certain piece of land, the more favorable the conditions for the growth and development of plants. Other inhabitants feel more comfortable, as it is easier for them to build their dwellings in loose soil and breathe in it, enriched with oxygen.

Charles Darwin wrote: “The plow is one of the most ancient and highest value inventions of mankind; but long before his invention the soil was properly tilled by worms, and always will be tilled by them.”

The fertility restored by worms, the structure and health of the soil make it possible to guarantee high yields on them, so the presence of earthworms in the soil is an important indicator.

Worms can be used on the farm: for processing garbage, manure, sawdust. Passing through the intestines of the worm, these wastes turn into fertilizers.

Completing my research work, I can say with full confidence that the benefits of these small, nondescript workers are enormous. They occupy an important stage in nature. Earthworms must be protected and conditions must be created for their life and reproduction.

In nature, everything is interconnected, and with the disappearance of a simple earthworm, irreparable changes can occur in the fertile soil layer, which will entail disruptions in the development of flora and fauna.

Conclusion.

Conducting scientific, research work on observing the life of earthworms, I learned a lot of interesting things, drew attention to things that previously seemed unimportant, not significant.

I did, in my opinion, very important findings that other children need to know. I think that my work will help other people to understand that there is nothing unnecessary in nature. It is very important to take care of everything that surrounds us, because the disappearance of an inconspicuous, even outwardly unpleasant, simple earthworm can lead to irreparable imbalances in nature.

It is necessary to remember the invaluable contribution that earthworms make to soil formation.

1. Fertilization of the soil occurs, as the worms drag the remains of leaves and grass into their holes.

2. Loosen the soil, allowing more oxygen to penetrate into it.

3. They pass the soil through their intestines, mix the soil layers, enriching it with oxygen.

4. They are soil formers.

5. Thanks to their activities, plant growth improves. living conditions of animals that live in the earth.

6. But most importantly, I realized that everything in nature is interconnected. Each living organism makes its own invaluable contribution to improving the lives of other plants and animals, to improving the living conditions of man himself.