Our planet is formed by four main shells: atmosphere, hydrosphere, biosphere and lithosphere. All of them are in close interaction with each other, since representatives of the biosphere shell of the Earth - animals, plants, microorganisms - cannot exist without such forming substances as water and oxygen.
Just like the lithosphere, the soil cover and other deep layers cannot exist in isolation. Even though we cannot see it with the naked eye, the soil is very densely populated. What kind of living creatures does not live in it! Like all living organisms, they also need water and air.
What animals live in the soil? How do they influence its formation and how do they adapt to such an environment? We will try to answer these and other questions in this article.
What are soils?
Soil is only the topmost, very shallow layer that makes up the lithosphere. Its depth goes by about 1-1.5 m. Then a completely different layer begins, in which groundwater flows.
That is, the top fertile soil layer - this is the very habitat of various shapes, sizes andmethods of nutrition of living organisms and plants. The soil, as a habitat for animals, is very rich and diverse.
This structural part of the lithosphere is not the same. The formation of the soil layer depends on many factors, mainly on environmental conditions. Therefore, the types of soils (fertile layer) also differ:
- Podzolic and sod-podzolic.
- Black Earth.
- Sod.
- Marsh.
- Podzolic marsh.
- Solodi.
- Floodplain.
- S alt flats.
- Gray forest-steppe.
- S alt licks.
This classification is given only for the area of Russia. On the territory of other countries, continents, parts of the world, there are other types of soils (sandy, clayey, arctic-tundra, humus, and so on).
Also, all soils are not the same in terms of chemical composition, moisture supply and air saturation. These figures vary and depend on a number of conditions (for example, it is influenced by animals in the soil, which will be discussed below).
How are soils formed and who helps them in this?
The beginning of the soil lead from the time of the appearance of life on our planet. It was with the formation of living systems that the slow, continuous and self-renewing formation of soil substrates began.
Proceeding from this, it is clear that living organisms play a certain role in soil formation. Which one? Basically, this role is reduced to the processing of organic substances contained in the soil, and its enrichment with mineral elements. Also this loosening and improvementaeration. M. V. Lomonosov wrote very well about this in 1763. It was he who first made the statement that the soil is formed due to the death of living beings.
In addition to the activities carried out by animals in the soil and plants on its surface, rocks are a very important factor in the formation of the fertile layer. It is from their variety that the type of soil will generally depend.
Abiotic factors also play a role:
- light;
- humidity;
- temperature.
As a result, rocks are processed under the influence of abiotic factors, and microorganisms living in the soil decompose animal and plant remains, turning organic matter into minerals. As a result, a fertile soil layer of a certain type is formed. At the same time, animals living underground (for example, worms, nematodes, moles) provide its aeration, that is, oxygen saturation. This is achieved by loosening and constant processing of soil particles.
Animals and plants work together to provide organic matter to the soil. Microorganisms, protozoa, unicellular fungi and algae process this substance and convert it into the desired form of mineral elements. Worms, nematodes and other animals again pass soil particles through themselves, thereby forming organic fertilizer - biohumus.
Hence the conclusion: soils are formed from rocks as a result of a long historical period under the influence of abiotic factors and with the help provided by animals andplants that live in them.
Invisible soil world
A huge role not only in the formation of the soil, but also in the life of all other living beings is played by the smallest creatures that form a whole invisible soil world. Who is one of them?
First, unicellular algae and fungi. From fungi, divisions of chytridiomycetes, deuteromycetes and some representatives of zygomycetes can be distinguished. Of the algae, phytoedaphons, which are green and blue-green algae, should be noted. The total mass of these creatures per 1 ha of soil cover is approximately 3100 kg.
Secondly, there are numerous microorganisms, bacteria and animals in the soil, such as protozoa. The total mass of these living systems per 1 ha of soil is approximately 3100 kg. The main role of unicellular organisms is reduced to the processing and decomposition of organic residues of plant and animal origin.
The most common of these organisms are:
- rotifers;
- pincers;
- ameba;
- Symphyl centipedes;
- protours;
- springballs;
- two-tails;
- blue-green algae;
- green unicellular algae.
What animals live in soil?
Soil inhabitants include the following invertebrates:
- Small crustaceans (crustaceans) - about 40 kg/ha
- Insects and their larvae - 1000 kg/ha
- Nematodes and roundworms - 550 kg/ha
- Snails and slugs - 40 kg/ha
Such animals living in the soil are very important. Their value is determined by the ability to pass soil lumps through themselves and saturate them with organic substances, forming vermicompost. Also, their role is to loosen the soil, improve oxygen saturation and create voids that are filled with air and water, resulting in increased fertility and quality of the top layer of the earth.
Let's consider what animals live in the soil. They can be divided into two types:
- permanent residents;
- temporarily inhabiting.
Mole rats, mole voles, zokors and marsupial moles belong to permanent vertebrate mammals, representing the fauna of the soil. Their significance comes down to maintaining food chains, as they are saturated with soil insects, snails, mollusks, slugs, and so on. And the second meaning is the digging of long and winding passages, allowing the soil to be moistened and enriched with oxygen.
Temporary inhabitants, representing the fauna of the soil, use it only for a short-term shelter, as a rule, as a place for laying and storing larvae. These animals include:
- jerboas;
- gophers;
- badgers;
- bugs;
- cockroaches;
- other types of rodents.
Adaptation of soil inhabitants
In order to live in such a difficult environment as the soil, animals must have a number of special adaptations. After all, according to physical characteristics, this medium is dense, rigid and low in oxygen. Exceptthere is absolutely no light in it, although there is a moderate amount of water. Naturally, one must be able to adapt to such conditions.
Therefore, animals that live in the soil, over time (during evolutionary processes) have acquired the following features:
- extremely small size to fill tiny spaces between soil particles and feel comfortable there (bacteria, protozoa, microorganisms, rotifers, crustaceans);
- flexible body and very strong musculature - advantages for movement in the soil (annelids and roundworms);
- the ability to absorb oxygen dissolved in water or breathe the entire surface of the body (bacteria, nematodes);
- life cycle, consisting of a larval stage, during which no light, no moisture, no nutrition is required (larvae of insects, various beetles);
- larger animals have adaptations in the form of powerful burrowing limbs with strong claws that make it easy to break through long and winding passages underground (moles, shrews, badgers, and so on);
- mammals have a well-developed sense of smell, but practically no sight (moles, zokors, mole rats, spews);
- streamlined body, dense, compressed, with short, hard, close-fitting fur.
All these devices create such comfortable conditions that animals in the soil feel no worse than those living in the ground-air environment, and perhaps even better.
The role of soil ecological groupsinhabitants in nature
The main ecological groups of soil inhabitants are considered to be:
- Geobionts. Representatives of this group are animals for which the soil is a permanent habitat. It goes through their entire life cycle in combination with the main processes of life. Examples: earthworms, multi-tails, tailless, two-tailed, no-tails.
- Geophiles. This group includes animals for which the soil is an obligatory substrate during one of the phases of their life cycle. For example: insect pupae, locusts, many beetles, weevil mosquitoes.
- Geoxens. An ecological group of animals for which the soil is a temporary shelter, shelter, place for laying and breeding offspring. Examples: many beetles, insects, all burrowing animals.
The totality of all animals of each group is an important link in the overall food chain. In addition, their vital activity determines the quality of soils, their self-renewal and fertility. Therefore, their role is extremely important, especially in today's world, in which agriculture forces soils to become poor, leached and s alted out under the influence of chemical fertilizers, pesticides and herbicides. Animal soils contribute to a faster and more natural restoration of the fertile layer after severe mechanical and chemical attacks by humans.
Connection of plants, animals and soils
Not only animal soils are interconnected, forming a common biocenosis with their food chains and ecological niches. In fact, all existing plants, animals and microorganismsinvolved in the same circle of life. As well as all of them are associated with all habitats. Here is a simple example illustrating this relationship.
Grasses of meadows and fields are food for land animals. Those, in turn, serve as a source of food for predators. The remains of grass and organic matter, which are excreted with the waste products of all animals, enter the soil. Here, microorganisms and insects, which are detritophages, are taken to work. They decompose all residues and convert them into minerals that are convenient for absorption by plants. Thus, plants receive the components they need for growth and development.
In the soil itself, at the same time, microorganisms and insects, rotifers, beetles, larvae, worms, and so on become food for each other, and therefore a common part of the entire food network.
Thus, it turns out that animals living in the soil and plants living on its surface have common points of intersection and interact with each other, forming a single common harmony and force of nature.
Poor soils and their inhabitants
Poor soils are soils that have been repeatedly exposed to human impact. Construction, cultivation of agricultural plants, drainage, melioration - all this eventually leads to soil depletion. What inhabitants can survive in such conditions? Unfortunately not many. The most hardy underground inhabitants are bacteria, some protozoa, insects, and their larvae. mammals,worms, nematodes, locusts, spiders, crustaceans cannot survive in such soils, therefore they die or leave them.
Also poor are soils that are low in organic and mineral matter. For example, loose sands. This is a special environment in which certain organisms live with their adaptations. Or, for example, saline and highly acidic soils also contain only specific inhabitants.
Study soil animals at school
The school zoology course does not provide for the study of soil animals in a separate lesson. Most often, this is just a brief overview in the context of a topic.
However, in elementary school there is such a subject as "The World Around". Animals in the soil are studied in the framework of the program of this subject in great detail. Information is presented according to the age of the children. Kids are told about the diversity, role in nature and human economic activity that animals play in the soil. Grade 3 is the most suitable age for this. Children are already educated enough to learn some terminology, and at the same time they have a great craving for knowledge, for knowing everything around them, studying nature and its inhabitants.
The main thing is to make the lessons interesting, non-standard, as well as informative, and then the children will absorb knowledge like sponges, including about the inhabitants of the soil environment.
Examples of animals living in the soil environment
You can give a short list, reflecting the main soil inhabitants. Naturally, it will not work to make it complete, because there are so many of them! However, we will try to name the main representatives.
Soil animals - list:
- rotifers, mites, bacteria, protozoa, crustaceans;
- spiders, locusts, insects, beetles, centipedes, wood lice, slugs, snails;
- earthworms, nematodes and other roundworms;
- moles, mole rats, mole rats, zokors;
- jerboas, ground squirrels, badgers, mice, chipmunks.
