The structure of an earthworm. Earthworm circulatory system: description, structure and features
The body of the earthworm is round in shape; the length of most representatives of this genus is no more than 15 centimeters, occasionally more than twenty, and the length of the largest is slightly more than thirty centimeters.
Consists of 100-180 segments. The segments have small, fairly elastic bristles that are practically invisible, but if you run your finger from the rear tip to the front, you can immediately feel it. The worm needs bristles so that it can cling to uneven ground surfaces while moving.
On the front of the worm's body there is a small thickening that serves as the place where the genital organs are located. The cells located in this thickening are activated during reproduction to lay eggs. If you look closely, you will notice that the belly of the earthworm is somewhat lighter than the rest of the parts. The worm has not only a circulatory system, but also a nervous, tactile and digestive system.
What environment do earthworms live in?
During the daytime, worms prefer to stay in the soil of the swarm, with passages in it. Light soil, the worm drills with its front tip. To do this, he first compresses the front part so that it becomes thinner, and tries to push it forward between the soil lumps. Subsequently, the front tip becomes thicker, the lumps move apart, and the worm pulls up the back part. In hard soil, raincoats make passages for themselves, passing them through the intestinal tract. Earthen heaps are often visible on the surface of the earth - these are traces of the night activity of worms. They emerge from their burrows after heavy rainfall (that’s why they are called rainfall). In the summer, worms prefer to stay in the upper layers of the soil, and in the winter, to escape the cold, they dig holes, the depth of which can be more than two meters.
As the temperature drops, they become less active and their circulatory system circulates more slowly.
Taking a worm in your hands, you will find that its skin is moist, and it itself is covered with mucus, which makes it easier to move in the ground. Apart from this, only through the moist skin does the oxygen required for respiration find its way into his body. This is how the worm breathes.
Directly under the skin there are circular muscles fused with it, and underneath them are longitudinal muscles. Those. An earthworm is a kind of skin-muscular sac. Thanks to the circular muscles, the body of the worm becomes thinner and longer, and thanks to the longitudinal muscles, it shortens and thickens. Due to the alternate functioning of these data, the muscle and the worm move.
How does an earthworm work?
The structure of an earthworm, when compared with the organisms of other animals, is quite primitive, but it has quite interesting features. Under the skin-muscular pouch there is a fluid-filled cavity of the body, and it contains the internal organs. When compared with roundworms, the body cavity of a roundworm is divided by septa, the number of which is equal to the number of segments. They have their own separate walls and are located under the skin-muscular pouch.
Now let's take a closer look at all the available organs of the worm.
Digestive system
The earthworm's mouth is located at the front. The puffball prefers rotting vegetation, swallowing it with soil. Likewise, he often drags fallen leaves into his hole. Swallowing is accomplished through the pharynx. Next, the food ends up in the intestines. Food that has not had time to be digested comes out through the anus located at the back. This is how the digestive system works in almost all types of worms. The worm also needs its mouth in order to drag various small objects to which it simply sticks. As you can see, the digestive system is quite primitive and lacks the organs that higher beings have.
The earthworm has a closed circulatory system, but there are some peculiarities. It is based on two main vessels, the dorsal and the abdominal, which are connected to each other using ring vessels, in some ways very similar to arteries and veins. Depending on the species, the blood of worms can be colorless, red or even green.
Speaking about the circulatory system of the earthworm, the dorsal vessel, which pulsates blood throughout the body, deserves special attention.
Special vessels that cover the intestines and are located in all segments, distill blood into the cavity of the abdominal vessel, which cannot pulsate on its own. The worm's blood flow is from front to back. In addition to these blood flows, there are also vessels that carry blood from the dorsal to the parapodial vessels. In them, the blood oxidizes when it comes into contact with environmental oxygen.
The skin of an annelid worm also has its own vessels, which are connected to the general circulatory system. Those. The circulatory system of worms is quite complex, but it is thanks to it that worms survive in rather difficult conditions.
Nervous system
The nervous system of annelids consists of two nerve trunks. Nerve nodes are formed in the segments on them. those. a kind of nerve chain emerges. In front, two nodules are connected to each other by circular bridges - a perioral nerve ring is formed. Nerves go from the nodules to various organs.
The rain cervix has an elongated body, 10-16 cm long. In cross-section, the body is round, but, unlike roundworms, it is divided by annular constrictions into 100-180 segments. Each segment has small elastic bristles. They are almost invisible, but if we run our fingers from the back end of the worm's body to the front, we will immediately feel them. With these bristles, the worm clings to uneven soil when moving.
Figure: earthworm and worm movement in soil
Earthworm Habitat
During the day, worms stay in the soil, making tunnels in it. If the soil is soft, then the worm drills it with the front end of the body. At the same time, he first compresses the front end of the body so that it becomes thin, and pushes it forward between the lumps of soil. Then the front end thickens, pushing the soil apart, and the worm pulls up the rear part of the body. In dense soil, the worm can eat its way through the soil through its intestines. Heaps of earth can be seen on the surface of the soil - they are left here by worms at night. They also come to the surface after heavy rain (hence the name rain). In summer, worms stay in the surface layers of the soil, and in winter they dig burrows up to 2 m deep.
Skin-muscle bag
If we take a worm in our hands, we will find that its skin is moist and covered with mucus. This mucus makes it easier for the worm to move through the soil. In addition, only through moist skin does the oxygen necessary for breathing penetrate into the worm’s body.
Under the skin there are circular muscles fused with it, and under them a layer of longitudinal muscles - a skin-muscular sac is obtained. The circular muscles make the body of the worm thin and long, while the longitudinal muscles shorten and thicken. Thanks to the alternating work of these muscles, the movement of the worm occurs.
Body cavity of an earthworm
Figure: internal structure of an earthworm
Under the skin-muscle sac is a fluid-filled body cavity in which the internal organs are located. This body cavity is not continuous, like in roundworms, but is divided by transverse partitions according to the number of segments. It has its own walls and is located under the skin-muscle sac
Digestive organs of an earthworm
Picture: Digestive system of an earthworm
The mouth is located at the anterior end of the body. The earthworm feeds on rotting plant debris, which it swallows along with the soil. It can also drag fallen leaves from the surface. Swallowing is done by the muscular pharynx. The food then enters the intestines. Undigested remains, along with soil, are expelled through the anus at the rear end of the body.
Figure: circulatory system of an earthworm
The earthworm's circulatory system serves to transport oxygen and nutrients primarily to the muscles. An earthworm has two main blood vessels: dorsal blood vessel, along which blood moves from back to front, and abdominal blood vessel, through which blood flows from front to back. Both vessels in each segment are connected to annular vessels. Several thick annular vessels have muscular walls, due to the contraction of which blood moves. From the main vessels, thinner ones depart, which then branch into the smallest capillaries. These capillaries receive oxygen from the skin and nutrients from the intestines, and these substances are released from other similar capillaries that branch in the muscles. Thus, the blood moves all the time through the vessels and does not mix with the cavity fluid. Such a circulatory system is called a closed circulatory system.
Excretory system of an earthworm
Liquid waste, processed substances enter the body cavity. Each segment contains a pair of tubes. Each tube has a funnel at the inner end; processed waste substances enter it and are discharged through the tube through the opposite end to the outside.
Figure: earthworm nervous system
A pair of nerve trunks runs along the entire body of the worm along the ventral side. In each segment they have developed nerve nodes- it turns out nerve cord. In the front part, two large nodes are connected to each other by ring jumpers - a peripharyngeal nerve ring. Nerves extend from all nodes to various organs.
Sense organs of an earthworm
There are no special sense organs, but sensitive cells in the skin allow the earthworm to sense touch on its skin and distinguish light from dark.
Reproductive system and reproduction of the earthworm
Earthworms are hermaphrodites. Before laying eggs, two worms come into contact for a while and exchange seminal fluid - sperm. Then they disperse, and mucus is released from the thickening (belt) located on the front of the worm. This mucus contains eggs. Then a lump of mucus with eggs slides off the worm's body and hardens into cocoon. Young worms emerge from the cocoon.
Well-known earthworms constitute a large group of species belonging to different families of oligochaetes.
Our common earthworm, reaching 30 centimeters in length and a centimeter in thickness, belongs to the most fully studied family Lumbricidae, which includes about 200 species, of which about a hundred are found in Russia.
Types of earthworms
According to the peculiarities of biology, earthworms can be divided into two types: the first includes worms that feed on the soil surface, the second - those that feed in the soil. In the first type, one can also distinguish litter worms, which live in the litter layer and under no circumstances (even when the soil dries out or freezes) do not sink deeper than 5-10 centimeters into the ground. This type also includes soil-litter worms, which penetrate the soil deeper than 10-20 centimeters, but only under unfavorable conditions, and burrow worms, which make constant deep passages (up to 1 meter or more), which they usually do not leave, but when When feeding and mating, only the front end of the body protrudes onto the soil surface. The second type can be divided into burrowing worms, living in the deep soil horizon, and burrowing worms, which have constant passages, but feed in the humus horizon.
Litter and burrowing worms inhabit places with waterlogged soils - the banks of reservoirs, swampy soils, soils of humid subtropics. In the tundra and taiga, only litter and soil-litter forms live, and in the steppes - only soil ones. They feel best in coniferous-deciduous forests: all types of lumbricids live in these zones.
Lifestyle of worms
According to their way of life, worms are nocturnal animals, and at night you can watch them swarming everywhere in large numbers, while remaining with their tails in their burrows. Stretching out, they scour the surrounding space, grab with their mouths (at the same time the worm's throat turns slightly outward and then retracts back) raw fallen leaves and drag them into burrows.
Earthworms are omnivores. They swallow a huge amount of soil, from which they assimilate organic matter, and they also eat a large number of all kinds of half-rotten leaves, with the exception of those that are very hard or have an unpleasant odor. When keeping worms in pots with soil, you can observe how they eat the fresh leaves of some plants.
Very interesting observations of earthworms were made by Charles Darwin, who devoted a lot of research to these animals. In 1881, his book “The Formation of the Vegetative Layer by the Activity of Earthworms” was published. Charles Darwin kept earthworms in pots filled with soil and conducted interesting experiments to study the feeding and behavior of these animals. So, in order to find out what kind of food, besides leaves and earth, worms can eat, he pinned pieces of boiled and raw meat on the surface of the earth in a pot and observed how every night the worms tugged at the meat, and most of the pieces were eaten. They also ate pieces of dead worms, for which Darwin even called them cannibals.
Half-rotten or fresh leaves are dragged by worms through the holes of the burrows to a depth of 6-10 centimeters and eaten there. Darwin observed how worms capture food objects. If you pin fresh leaves to the surface of the ground in a flower pot, the worms will try to drag them into their holes. They usually tear off small pieces, capturing the edge of the leaf between the prominent upper and lower lips. At this time, the thick, powerful pharynx protrudes forward and thereby creates a fulcrum for the upper lip. If the worm encounters a flat, large surface of the leaf, it acts differently. The anterior rings of the body are slightly retracted into the subsequent ones, due to which the anterior end of the body expands and becomes blunt with a small pit at the end. The pharynx is moved forward, pressed against the surface of the sheet, and then, without detaching, it is pulled back and slightly expanded. As a result, a “vacuum” is formed in the hole at the front end of the body, applied to the leaf. The pharynx acts like a piston, and the worm is very firmly attached to the surface of the leaf. If you place a thin wilting cabbage leaf on the worm, then on the back side of the worm you can see a depression directly above the head end of the animal. The worm never touches the leaf veins, but sucks out the delicate tissues of the leaves.
Worms use leaves not only for food, but also plug the entrances to their burrows with them. For this purpose, they also drag pieces of stems, wilted flowers, scraps of paper, feathers, and scraps of wool into holes. Sometimes tufts of leaf petioles or feathers protrude from the worm's hole.
Leaves dragged into worm holes are always crumpled or folded into a large number of folds. When the next leaf is pulled in, it is placed outside the previous one, all the leaves are tightly folded and pressed together. Sometimes the worm widens the hole in its burrow or makes another one nearby to collect even more leaves. The worms fill the gaps between the leaves with moist soil thrown out of their intestines in such a way that the burrows are completely clogged. Such clogged burrows are especially common in the fall before the worms overwinter. The upper part of the passage is lined with leaves, which, as Darwin believed, prevents the worm's body from coming into contact with the cold and wet earth at the surface of the soil.
Darwin also described how earthworms dig holes. They do this either by pushing the earth in all directions or by swallowing it. In the first case, the worm pushes the narrow front end of its body into the cracks between the soil particles, then swells and contracts it, and thereby the soil particles move apart. The front end of the body works like a wedge. If the soil or sand is very dense, compacted, the worm cannot move the soil particles apart and acts in a different way. He swallows the soil, and, passing it through himself, gradually sinks into the ground, leaving behind a growing pile of excrement. The ability to absorb sand, chalk or other substrates completely devoid of organic matter is a necessary adaptation for the case when a worm, plunging into the soil from excessive dryness or cold, finds itself in front of unloosened dense layers of soil.
The burrows of the worms go either vertically or slightly at an angle. They are almost always lined on the inside with a thin layer of black earth processed by animals. Lumps of earth expelled from the intestines are compacted along the walls of the burrow by vertical movements of the worm. The lining thus formed becomes very hard and smooth and adheres closely to the body of the worm, and the backward-curved bristles have excellent points of support, which allows the worm to move very quickly back and forth in the burrow. The lining, on the one hand, strengthens the walls of the burrow, on the other hand, protects the worm’s body from scratches. Minks leading down usually end in an extension, or chamber. Here the worms spend the winter, alone or in a ball of several individuals. The burrow is usually lined with small pebbles or seeds, which creates a layer of air for the worms to breathe.
After the worm swallows a portion of the earth, regardless of whether it is done for food or for digging, it rises to the surface to throw out the earth. The discarded soil is saturated with intestinal secretions and, as a result, becomes viscous. Once dry, the lumps of excrement harden. The earth is thrown out by the worm not randomly, but alternately in different directions from the entrance to the hole. The tail works like a shovel. As a result, a kind of tower of lumps of excrement is formed around the entrance to the burrow. Such turrets of different species of worms have different shapes and heights.
Earthworm coming out
When a worm emerges from a burrow to throw out excrement, it extends its tail forward, but if it sticks out its head to collect leaves. Consequently, worms have the ability to turn over in their burrows. Worms do not always release excrement onto the soil surface. If they find some kind of cavity, for example, near the roots of trees, in recently dug up soil, they deposit their excrement there. It is easy to notice that the space under stones or fallen tree trunks is always filled with small pellets of earthworm excrement. Sometimes animals fill the cavities of their old burrows with them.
Life of earthworms
Earthworms played a much more important role in the history of the formation of the earth's crust than it might seem at first glance. They are numerous in almost all wet areas. Due to the digging activity of worms, the surface layer of soil is in constant motion. As a result of this “digging,” soil particles rub against each other, new layers of soil brought to the surface are exposed to carbon dioxide and humic acids, which contributes to the dissolution of many minerals. The formation of humic acids is due to the digestion of semi-decomposed leaves by earthworms. It has been established that worms help increase the content of phosphorus and potassium in the soil. In addition, passing through the intestinal tract of worms, soil and plant debris are glued together by calcite, a derivative of calcium carbonate secreted by the calcareous glands of the worms' digestive system. The excrement, compressed by contractions of the intestinal muscles, is thrown out in the form of very strong particles, which are eroded much more slowly than simple lumps of earth of the same size and represent elements of the granular structure of the soil. The quantity and mass of excrement produced annually by earthworms is enormous. During the day, each worm passes through its intestines an amount of earth approximately equal to the weight of its body, i.e. 4-5 grams. Every year, earthworms release a layer of excrement 0.5 centimeters thick onto the surface of the earth. Charles Darwin counted them up to 4 tons of dry mass per hectare of English pastures. Near Moscow, in a field of perennial grasses, earthworms annually produce 53 tons of excrement per hectare of land.
Worms prepare the soil in the best way for plants to grow: they loosen it so that there is no lump left larger than they can swallow, and they facilitate the penetration of water and air into the soil. Dragging the leaves into their burrows, they crush them, partially digest them and mix them with earthen excrement. By evenly mixing the soil and plant debris, they prepare a fertile mixture, like a gardener. Plant roots move freely in the soil along the earthworm passages, finding rich nutritious humus in them. One cannot help but be surprised when you think that the entire fertile layer has already passed through the bodies of earthworms and in a few years will pass through them again. It is doubtful, Darwin believes, that there are other animals that would occupy such a prominent place in the history of the earth’s crust as these essentially lowly organized creatures.
Thanks to the activity of worms, large objects and stones gradually sink deep into the earth, and small fragments of stones are gradually ground into sand in their intestines. Darwin, describing how abandoned castles in old England were gradually sinking underground, emphasized that archaeologists should be indebted to earthworms for the preservation of a large number of ancient objects. After all, coins, gold jewelry, stone tools, etc., falling on the surface of the earth, are buried for several years under the excrement of worms and are thereby reliably preserved until the earth covering them is removed in the future.
Earthworms, like many other animals, are susceptible to human activities. Their numbers are declining due to excessive use of fertilizers and pesticides, cutting down trees and shrubs, and under the influence of overstocking. 11 species of earthworms are included in the Red Book of the Russian Federation. Successful attempts have been made repeatedly to relocate and acclimatize worms of various species to areas where they are scarce. Such activities are called zoological reclamation.
Many people underestimate the importance of the work of earthworms. These representatives of the invertebrate kingdom are best known for crawling out of the ground in large numbers after heavy rain. They are often used as bait by numerous fishing enthusiasts. Darwin also noted the fact that worms perform an important function in nature, acting as a kind of agricultural technicians. In the process of creating an extensive system of tunnels, which the earthworm digs through, excellent aeration is formed by supplying air to the inner layers of the soil.
Thanks to excellent aeration, the respiratory activity of many plants is facilitated. Feeding on organic matter and waste, worms ensure the grinding of soil components, enriching them with their secretions. The amazing ability of representatives of this species is the ability to disinfect large areas of soil, sterilizing it from harmful bacteria. Thanks to countless holes, forming a kind of capillary system, ideal drainage and aeration of the soil is ensured.
The body of an earthworm can reach three meters in length. However, on the territory of Russia there are mainly individuals whose body length does not exceed 30 centimeters. In order to move, the worm uses small bristles, which are located on different parts of the body. Depending on the variety, there can be from 100 to 300 segments. The circulatory system is closed and very well developed. It consists of one artery and one central vein.
The structure of an earthworm is very unusual. Breathing is realized with the help of special hypersensitive cells. The skin produces protective mucus with a sufficient amount of natural antiseptics. The structure of the brain is quite primitive and includes only two nerve nodes. Based on the results of laboratory experiments, earthworms have confirmed their outstanding regeneration abilities. The severed tail grows back after a short period of time.
The genital organs of the earthworm are also very unusual. Each individual is a hermaphrodite. She also has male organs. Based on biological factors, all such worms can be divided into several subgroups. Representatives of one of them search for food on the surface of the soil layer. Others use the soil itself for food and emerge from the ground extremely rarely.
The earthworm is a type of annelid. Under the skin layer there is a developed muscle system consisting of muscles of various shapes. The mouth opening, from which food enters the esophagus through the pharynx, is located on the front of the body. From there it is transported to the area of the enlarged crop and the small size of the muscular stomach.
Burrowing and bedding earthworms live in places with loose and moist soil. Preference is given to moist soils of the subtropics, marshy lands and the banks of various reservoirs. In steppe areas, soil varieties of worms are usually found. Litter species live in the taiga and forest-tundra. The coniferous broad-leaved strip can boast the highest concentration of individuals.
What kind of soil do worms like?
Why do earthworms love sandy loam and loam soils? Such soil is characterized by low acidity, which is best suited for their life. Acidity levels above pH 5.5 are detrimental to the organisms of these representatives of the ringed type. Moist soils are one of the prerequisites for population expansion. During dry and hot weather, worms go deep underground and lose the opportunity to reproduce.
Character and lifestyle of the earthworm
The active and productive life of an earthworm occurs at night. As soon as night falls, many individuals crawl to the surface of the ground in search of food. However, the tail usually remains in the ground. By morning, they return to their holes with prey, dragging pieces of food into them and masking the entrance to their shelter with blades of grass and leaves.
The role of earthworms in nature is difficult to overestimate. The worm literally passes an incredible amount of soil mixture through itself, enriching it with beneficial enzymes and killing harmful substances and bacteria. The worm moves by crawling. Retracting one end of the body and clinging to the roughness of the ground with its bristles, it pulls up the back part, making its many passages in a similar way.
How do earthworms survive winter?
During the winter, the vast majority of individuals hibernate. A sharp drop in temperature can instantly destroy worms, so they try to burrow into the soil to a depth in advance, often exceeding one meter. Earthworms in the soil perform the most important function of its natural renewal and enrichment with various substances and microelements.
Benefit
In the process of digesting semi-fermented leaves, the worms’ body produces specific enzymes that contribute to the active generation of humic acid. Soil that has been loosened by earthworms is optimal for a wide variety of representatives of the plant kingdom. Thanks to a system of intricate tunnels, excellent aeration and ventilation of the roots is ensured. Thus, the movement of the earthworm is an important factor in the task of restoring the beneficial qualities of the soil.
The earthworm is in fact very useful for humans. It makes the soil layers fertile and enriches them with all kinds of nutrients. However, the total number of individuals in many regions of Russia is rapidly declining. This happens due to the uncontrolled introduction of pesticides, fertilizers and mineral mixtures into the soil. Earthworms are also hunted by numerous birds, moles, and various rodents.
What do earthworms eat?
At night, the earthworm crawls to the surface and pulls the half-rotten remains of plants and leaves into its shelter. Also, its diet includes soil rich in humus. One representative of the species can process up to half a gram of soil per day. Considering that up to several million individuals can live simultaneously on an area of one hectare, they are capable of acting as irreplaceable soil converters.
After rain, you can see a large number of worms on the asphalt and soil surface, what makes them crawl out? Even the name “earthworms” indicates that they love moisture very much and become more active after rain. Let's consider several possible reasons why earthworms crawl out to the surface of the earth after rain.
Soil temperature
It is believed that worms crawl to the surface in search of warmth, since after rain the soil temperature drops by several degrees, which causes discomfort for them.
Changes in acid-base balance
Another theory says that the worms crawl to the surface due to a change in the acid-base balance of the soil after rain, it becomes more acidic, which negatively affects these diggers. According to researchers, emergency evacuation to the soil surface saves them from death in an acidic environment.
Lack of air
The third theory explains that after rain there is more oxygen in the top layer of the soil, so the worms crawl up en masse. Water enriches the upper layers of the earth with oxygen, and many species of worms love moisture and vitally need sufficient oxygen. And through the surface of the body, oxygen is absorbed best in a humid environment.
Trips
British scientist Chris Lowe suggested that worms crawl to the surface of the earth during rain in order to make a long journey to new territory. On the surface, worms are able to crawl much further than underground, and dry soil causes discomfort when moving, strong friction is created, and grains of sand stick to the surface of the worm’s body, injuring it. And after rain, the surface of the earth is highly moistened, which allows them to freely travel to new areas of the ground.
The sound of rain
Another scientist, Professor Joseph Gorris from the USA, suggested that earthworms are frightened by the noise of rain, since the vibrations it creates are similar to the sound of the approach of their main enemy, the mole. That is why some fishermen use a technique to lure bait to the surface: they insert a stick into the ground, attach a sheet of iron to its surface and pull it so as to create a vibration, which will be transmitted into the ground through the stick. When frightened, the worms climb to the surface of the earth and become easy prey for experienced fishermen.
Reproduction and lifespan of earthworms
The earthworm is a hermaphrodite. It has both female and male genital organs. However, it is not capable of self-fertilization. With the onset of warm climatic conditions required for reproduction, individuals crawl in pairs, touching each other with their abdominal region, and perform a kind of seed exchange. Afterwards, the muff is transformed into a cocoon, in which the eggs develop.
Some varieties are distinguished by asexual reproduction. The worm's body splits in two, with one part regenerating the front end and the other regenerating the back end. There are also species of worms that reproduce without spermatheca by laying spermatophores. The lifespan of worms can exceed ten years.
Who hasn't seen earthworms? Yes, probably everything. However, many do not even realize what benefits they have brought and are bringing to us; it is very difficult to overestimate. This lengthy article is dedicated to earthworms. The reader can learn for himself about the structure, types, and lifestyle of worms underground. If you know nothing about these animals, then after reading the article your attitude towards them will radically change. At the end of the publication, several videos will be shown for your reference. The text will be accompanied by pictures and photos.
- These are quite large invertebrates, measuring up to 3 meters in length. Green worms that live in Russia belong to the order Haplotaxida (representatives of this order live throughout the Earth, with the exception of Antarctica) and to the family Lumbricidae, which includes about 200 species. About 97 representatives of this family live in Russia. The importance of earthworms for the earth's biosphere is very difficult to overestimate. They eat dead plant tissue and animal waste products, then digest it all and mix the resulting mass with the soil. People have learned to use this feature for their own purposes to obtain the most valuable fertilizer - vermicompost or vermicompost.
These protozoa get their name because when it rains, they crawl out of their holes and stay on the surface of the soil. This happens because rainwater fills their holes and they can’t breathe, so they crawl out to save themselves.
Biohumus is a hydrophilic structure that has the ability to accumulate moisture. That is, when there is not enough water in the soil, humus releases moisture, and when there is excess, it accumulates. The phenomenon of humus secretion by worms can be explained by studying their structure. The fact is that in the intestines of worms, after the breakdown of organic compounds, molecules of humic acids are formed, and they, in turn, come into contact with various mineral compounds.
Earthworms are very important in the formation of fertile soil, a fact noted by Charles Darwin. They dig holes 60-80 centimeters deep, thereby loosening the soil.
Today, people widely use worms for their own purposes. First of all, to obtain vermicompost. Worms are actively used in poultry and livestock farming for feeding. Worms are also widely used by amateur fishermen as good bait.
The structure of earthworms
The structure of earthworms quite simple. The length of individuals that are common in Russia varies from 2 to 30 centimeters. The entire body is divided into segments, there can be from 80 to 300. The earthworm moves with the help of very small bristles, which are located on each segment of the body, with the exception of the very first. There can be from 8 to 20 setae on one segment.
Picture: structure of an earthwormIn the attached picture you can visually observe the structure of the worm. You can determine the front part of the worm, where the mouth is, and the back part, where the anus is located. You can also notice segments.
They are characterized by a closed circulatory system, which is quite well developed. It includes one artery and one vein. The worm breathes thanks to very sensitive skin cells. The skin contains protective mucus, which contains a large number of antiseptic enzymes. The brain is poorly developed. It consists of only two nerve ganglia. It is very common for worms to exhibit the ability to regenerate. For example, if you cut off his tail, then after a while it will grow back.
Earthworms are hermaphrodites, each having both male and female reproductive organs. Reproduction occurs through the mating of two individuals. The genital organ of worms is a girdle; in size it occupies several anterior segments. The genital girdle is clearly visible on the body of the worm; it looks like a thickening. In this organ, the cocoon matures, from which small worms hatch after 2-3 weeks.
Types of earthworms
Earthworms that live in our country can be divided into two species, which differ in biological characteristics. The first type includes those worms that feed on the soil surface (litter), and the second type includes those that live and feed in the soil layers (burrows). The first species lives constantly on the soil surface; its representatives do not descend into soil layers that are below 10-20 centimeters.
Representatives of worms that belong to the second type develop their activities exclusively at a depth of 1 or more meters. If necessary, they stick out only the front part of their body from the ground.
The second species, in turn, can be divided into burrowing and burrowing worms. Burrowers live in deep layers of soil, but do not have permanent burrows. And burrow worms constantly live in the same burrows.
Earthworms of litter and burrowing species live exclusively in moist soils, for example, in places near water bodies. Burrowing worms can live in drier soils.
Lifestyle of worms underground
Worms are nocturnal. At this time of day you can observe their most active activity. At night they eat most of the food. Many crawl out to consume food, but rarely get out of their burrows completely - their tails always remain underground. During the day, worms plug their holes with various objects, such as tree leaves. They can drag small particles of food into their burrows.
For reference. The body of worms is very stretched, thanks to numerous segments. In addition, the worms have very tenacious bristles. In this regard, forcibly pulling him out of the mink is a rather difficult undertaking.
They are omnivorous. They have a very characteristic diet. First, they swallow a large amount of soil, and then absorb only useful organic substances from it.
Worms are able to digest even small quantities of animal feed, such as meat.
Eating of food occurs in burrows. First, the worm gropes for a tasty morsel from the outside and drags it into its hole, where the meal takes place. In order to capture the food object, the worm attaches itself very strongly to it, then pulls back with all its strength.
Moreover, the worms make a supply of food for themselves. They very carefully put it in their burrows. Worms can also deliberately dig another hole just to store food. They seal such a hole with damp soil and open it only if necessary.
It happens in the following order. First, the soil is swallowed, then the organic substances are digested inside the worm. After this, the worm crawls out and excretes excrement. Moreover, it stores waste products in one specific place. Thus, before entering the hole, a kind of pile of worm excrement is formed.
Life of worms
Life of earthworms has a very long history. They played a huge role in soil formation. It is thanks to them that we see the earth as it is today.
Worms are constantly engaged in digging activities, as a result of which the layer of earth is always in motion. Worms have a very large appetite. In just one day, he can eat a volume of food that is comparable in weight to him, that is, 3-5 grams.
As a result of their activity, worms contribute to the best growth of plants. Let's not even take into account the fertilizer they produce. Worms loosen the soil and facilitate better penetration of oxygen and water into it. Plant roots grow much better in worm holes.
As a result of constant loosening of the soil, large objects gradually sink deeper into the earth. Small foreign particles are gradually ground into the stomachs of worms and turn into sand.
Unfortunately, the number of earthworms in our country is declining. This is facilitated by the inappropriate use of chemicals to “fertilize” the soil. To date, 11 species of earthworms have already been included in the Red Book of Russia. Why use chemicals to fertilize the soil when there is such a miracle of nature as vermicompost?!
The role of earthworms in nature very large and unlikely to be overestimated. Worms play a huge role in the decomposition of organic matter. enrich the soil the most valuable fertilizer - humus. They can serve as an indicator: if there are a lot of them in the soil, then the land is fertile.
A complete understanding of the role of earthworms came to humans relatively recently. Until this point, they mainly resorted to the use of chemical mineral fertilizers, which destroyed the soil and all life in it. Unfortunately, many modern farmers are also in this misconception. Biohumus or vermicompost is a real magic wand for the soil. It contains very large amounts of potassium, phosphorus and nitrogen - substances that are primarily necessary for plant growth.
We've gone a little off topic. In wildlife, worms stay in places where there is a large amount of organic waste. A good example is the forest. When the leaves fall in the fall, they will need to go somewhere. Soil bacteria and, of course, earthworms will come to the rescue here. Immediately after the leaves fall, soil bacteria will get to work and decompose it to the compost stage. Then the worms will get to work and process the compost to the vermicompost stage and add this valuable fertilizer to the soil. In principle, this is how soil formation occurs.
The benefits of earthworms
During the Soviet Union, chemical mineral fertilizers began to be actively used in the Russian expanses, which over time destroy entire layers of soil. Today we have just come to the moment when the soil begins to rapidly collapse. Chernozem soils no longer give such good results as before. Unscrupulous farmers who think only about their income use fertilizers that are dangerous to the soil on their plots of land, thereby destroying it. But soil restoration takes a very long period of time, about 1 centimeter per 100 years.
The benefits of earthworms consists in the rapid restoration of the earth from chemical burns and other adverse effects. restore the very structure of the soil through the introduction and distribution of vermicompost. Even if the land does not need restoration, adding vermicompost to it will in any case be beneficial. It is impossible to contaminate chernozem or burn it with humus, unlike any other fertilizer. This is due to the fact that vermicompost has a very similar structure to chernozem. You can even say that humus is concentrated black soil.
With the help of worms you can bring great benefits to your vegetable garden, orchard or small household plot. To do this, you just need to learn how to breed worms yourself, and this is very easy to do. It is enough to dig a hole in the garden and put all organic waste there. Over time, the worms will appear there themselves. There is another option - buy worms. You can also breed worms in separate boxes. As you eat organic waste, the resulting vermicompost needs to be collected and scattered around the site.
Worms significantly improve the structure of the soil, improve water exchange and water exchange in it. In the garden or garden, it is necessary to create all the conditions for the development of worms. The most rational way would be to build a special box in which you can put all the weeds and other organic waste in the summer. Next year, if there are a large number of worms, you can already get ready-made fertilizer from this box, which can be used in different ways (see photo below). Some advise simply scattering it around the area, others bury it, and still others even prepare a liquid fertilizer based on it. In general, there are many ways to use it.
Earthworms - Vermiculture
A fairly large number of farmers and ordinary people who have their own household plots are engaged in breeding earthworms for the purpose of obtaining vermicompost. And this trend is not encouraging. Vermiculture may soon replace harmful chemical fertilizers.
Breeding worms can also be considered a good business idea. At minimal cost, you can get the most valuable fertilizer and sell it for good money. It is especially beneficial to engage in this business for those who have poultry or farm animals and do not know what to do with their waste products. The droppings of farm animals are excellent food for worms, which turns into vermicompost.
In this part of the article, one cannot fail to mention the type of worm that is the most productive - the Californian one. California worms were bred in 1959 in the USA. These earthworms are the most commonly used in this area due to their enormous productivity. The Californian worm lives as long as a regular one, but its reproduction rate is 100 times higher, and its lifespan is 4 times longer. However, they will have to provide certain conditions of detention.
Before introducing worms into the substrate, it must be prepared. It needs to turn into compost. It is most convenient to use ordinary metal barrels with a volume of 200 liters.
At home, you can breed worms in various containers. A wooden box with small holes to drain excess water at the bottom is best suited for these purposes; the substrate is placed there and the worms are released. In one summer, a box of organic waste can be turned into vermicompost. See photo:
Compost is placed here, and non-composted organic waste can be placed on top
You can use boxes of a different design, for example plastic ones, in which fruits and vegetables are transported:
The disadvantage of a plastic box is that the holes in the bottom are too large, through which the worm can escape.
Earthworms video
“The appetizing fruits and vegetables you see are not fakes. These beautiful fruits are real, and most importantly, environmentally friendly. And all this is due to the fact that they were obtained using an amazing fertilizer - vermicompost.” In this video we will talk about earthworms of the “prospector” breed. The video is very useful and educational.
This video was shown on television, this is the Galileo program. The report was prepared about earthworms.
To enlarge an image, simply click on it.