Soil and soil proximity to. Earth - the role of soil in nature and human life

The soil cover of the Earth seems to us ordinary and eternally existing in nature. However, it is not. Nature has been creating soil for 4.5 billion years! Weathering products formed the basis for the formation of soil rocks. Weathering is a complex process, the result of the combined action of many physical, chemical and biological factors. Video 37.

Conventionally, this is reflected in the formula:Rocks + Sun + air + water + living organisms = soil.

The process of soil formation never stops, of course, it continues today, but very slowly. The soil is in a constant process of development - formation or destruction. The duration of the process of formation of the soil cover of the Earth is due to many factors. It takes thousands of years for soil to form. In the same time irrational nature management, destructive to the soil, can destroy it in just a few years.

Do you think soil should be classified as renewable or non-renewable? natural resources? Is it possible to give an unambiguous answer to this question?

Thanks to the soil cover of the Earth, the life of plants, animals and humans is provided. The soil - essential component of all terrestrial ecological systems of the Earth and is itself a unique ecosystem (see topics 2 and 3 for details). It connects living organisms with the lithosphere, atmosphere and hydrosphere. The soil is the object of study of a separate science - soil science. The founder of soil science is an outstanding Russian scientist Vasily Vasilievich Dokuchaev. Petersburg is the Central Museum of Soil Science. V.V. Dokuchaev, which is one of the world's largest museums of soil and ecological profile. In the museum you can get answers to questions - What is soil? How is it formed? What grows in this soil? Who lives in this soil? The museum is the custodian of the richest collection of soils from various natural zones of the world.

Currently, scientists distinguish about a hundred types of soils. Why are there different types of soils?

The variety of soils is connected, of course, with the variety of conditions in which they were formed. Especially great importance have a climate and the properties of those rocks from which the soil was formed.

Look at the picture and compare chernozem, soddy-podzolic and tundra podzolic soils.

Do you know what soil types are typical for your area? The soil has several layers connected to each other. Video 38. Among them, the bedrock is distinguished, which is subjected to weathering when it comes to the surface, and the parent rock, from which upper layer soil. The underlying layer is called the subsoil.

The unique property of the soil is fertility. It is what ensures the existence of life on Earth. Soil fertility is due to the content of humic substances (humus) in it. Humus is an accumulation of organic substances that were formed during the decay of plant and other living things. It gives the soil a black color and ensures the growth and development of plants (i.e. life on Earth). The more humus in the soil, the more fertile it is. Most of the humus is found in chernozem soils. Video 39.

What is soil made of?

Approximately 50% of the space in the soil is occupied by air, filling the gaps between solid particles. Approximately 45% of the mass of the soil is minerals, about 5% - to the share of organic substances. However, these data on the composition of the soil do not give a real picture of it.

We are accustomed to thinking that the soil is sparsely populated, that the bulk of living organisms are on its surface. But that's not the case at all! For many animals it is a habitat. Everyone knows that they live in the soil and earthworms, and insect larvae, and the insects themselves. The soil serves as a nesting and dwelling place for many birds and other animals. Calculations of scientists show that the mass of living things in the soil is? masses of living inhabitants of forests and more? masses of living steppe vegetation.

It has been established that what smaller sizes organisms, the greater their number in the soil. So, in 1 m 3 of soil there are several tens of millions of worms and insects. And 1 gram of soil contains more than a million of the simplest microorganisms. In general, scientists estimate the number of soil microorganisms on Earth at approximately one billion tons!However, the significance of living organisms in soil processes is determined not by their mass, but by the enormous work that they perform. Video 40.

We do not notice the work of soil bacteria, which continuously process the dying parts of plants and other organisms. But if it stopped, the surface of the Earth would be littered with these remnants. It is hard to imagine what would happen to our beautiful Planet in a hundred years! And earthworms, as you know, eating, swallow the soil. If about 140 thousand earthworms live in one hectare of soil, then their mass is 500 kg! And this means that in one year they pass through their body about ten tons of soil mass!

What is the biospheric function of the soil?

It is important to understand that to characterize the soil, it is not enough to know its composition. scientific knowledge about the soil is connected with the understanding that it is a complex natural body with a certain structure (structure). Let's remember: the soil is not a mechanical mixture various substances. The soil is complex system interactions of mineral, organic substances and living organisms.

Thanks to their interaction, the soil performs its biospheric functions. But, we repeat, it is provided not only by the composition, but also by the structure of the soil.

Soil is made up of very small particles. Microscopic organisms live in a film of water enveloping soil particles. Larger ones settle between soil particles, as in caves. Both those and others make up a single formation with the soil. Those that live on the surface of the particles need air, and those that are inside the particles are able to live without air.

Nutrition, respiration and all other life processes of living organisms lead to many changes in the composition of the soil. At the same time, they involve in these processes substances contained in the air and dissolved in water, and they themselves release new substances formed in the course of their vital activity.

Thus, the soil performs its biospheric function as the final link that ensures the creation of the entire biomass of the Planet.

Soil destruction can occur both as a result of natural processes and under the influence of irrational human actions.

Destruction of the soil cover at the site of logging

Such natural processes, such as the advance of glaciers, volcanic eruptions, the formation of mountains, earthquakes, hurricanes, tornadoes or floods, cannot but affect the condition earth's crust and soil formation processes. But natural soil erosion (destruction and demolition of the upper most fertile layers as a result of the action of water and wind) is a slow continuous process, at the same time as a new soil layer is formed. Unlike natural, anthropogenic soil erosion is caused by human intervention in natural environment for economic purposes. Irrational use of fields and pastures, deforestation, drainage of reservoirs and the like - all this can destroy soil fertility in a very short time.

For example, the first settlers in America exploited the land so mercilessly that in 100 years they destroyed 20% of arable land. The soil is also destroyed due to waterlogging, desertification.

Bitter evidence of the reckless exploitation of nature by man is the desert North Africa, and the Baltic dunes, and eroded spaces in Australia, Pakistan, India and Canada. Only in the European part of our country there are up to 2 million ravines, which were formed mainly as a result of plowing the land. Every year, land loses a layer of fertile soil, the creation of which nature has spent thousands of years. Soil scientists call erosion a real tragedy.

Scientists believe that in order to preserve the ecological sustainability of the territory in each natural area a certain ratio of arable lands, pastures and forests must be observed. So, for example, in the forest-steppe, according to the research of V.V. Dokuchaev, forests should be 10-18%. Now, due to excessive plowing, there are much fewer of them left.

According to modern data, humanity has already lost historical period about 2 billion hectares of once fertile lands, turning them into man-made deserts. This is more than the area of all modern arable land in the world, which is 1.5 billion hectares. At the end of the 20th century, it became obvious that soil degradation has become rampant and is one of the main threats to the global environmental crisis. This is especially worrying when you consider that, according to the latest estimates, there are more than one billion hungry people in the world, that is, one in six people on the planet. This means that more people are now suffering from hunger and malnutrition than at any time in the history of mankind, while the fertility of the soil and the area suitable for Agriculture lands are shrinking.

Do we ever think about what soil means in our lives? Perhaps very rarely. It seems to us that since the soil is not a flower, not an insect, not a beast, what can happen to it? So it will always lie under your feet. And at the same time, the world-famous ecologist Jean Pierre Dorsta said: "The soil is our most precious capital. The life and well-being of the entire complex of terrestrial biocenoses, natural and artificial, ultimately depends on a thin layer that forms the topmost cover of the Earth."

By underestimating the role of this greatest natural wealth, mankind endangers its very existence.

The protection of the soil from its destruction, the fight against a decrease in its fertility is the most important ecological problem requiring urgent attention of the world community.

The question asked is by no means as primitive and simple as it might seem to someone at first. It should be noted right away that both soil and soil are the main subjects for studying the corresponding partially overlapping disciplines: soil science and soil science.

Russian term soil science relates to the specialized scientific discipline of soils as a separate natural body. This scientific discipline is part of natural science and belongs to the family of geosciences. Studies soil science structure, composition, properties, origin, development, distribution and fertility of soils, and also develops measures for their rational use / protection. The founding father of the discipline is Dokuchaev V.V., who wrote a monograph and a doctoral dissertation on the topic “Russian Chernozem”, and the year of its official defense (1883) began to be considered the “year of birth” of soil science.

A term similar in origin soil science is a specialized section of engineering geology, a separate science of soils. This scientific discipline explores the composition, structure, properties and state of soils, the soil massifs/thicknesses/bodies composed by them, as well as the patterns of their formation, changes in time/space under the influence of modern and predictable geoprocesses occurring in the earth's crust under the influence of the entire existing set of natural factors - and above all in connection with the engineering and economic / engineering and construction human activity. The object of study in soil science is any soil - from rocks, soils and sediments to artificial geological formations.

Definitions

Soil - the essence of the upper (surface) layer earth's lithosphere, which has fertility and is a polyfunctional open heterogeneous system of four phases (liquid / solid / gaseous plus living organisms), structurally formed as a result of the vital processes of organisms and weathering of rocks.

Soil is a dynamic multicomponent system (as mentioned above, it includes rocks, sediments / soils and man-made formations), which is part of the geological environment and is considered in direct connection with engineering and economic human activity.

Those who wish to receive more detailed interpretations will immediately refer to the relevant special literature, and here we will try to isolate key moment, important for "everyday" understanding - and will help us in this ... Ridley Scott's film "The Martian". Recall that in the context of interest to us main character is engaged in the purposeful transformation of Martian soil into soil, using available organic matter, water and microorganisms, ultimately achieving the manifestation of the main property of the soil - fertility in relation to the planted plant.

There is also a strict definition for the concept of “soil fertility”: it is the ability of the soil to satisfy the needs of the plants placed in it for nutrients, air and moisture, and also to provide them with conditions for normal life.

In this regard, it would also be useful to mention a couple more definitions that are already in circulation in the regulatory literature:

According to GOST 54003-2010, soil is either artificially created but at the same time fertile soil mass, or a fertile layer mechanically removed from the surface of any land plot or brought to it.
According to GOST 27593-88, soil is a natural-historical organo-mineral independent natural body formed on the earth's surface as a result of long-term exposure to abiotic, biotic and anthropogenic factors, including solid mineral / organic particles, air and water, and also having special genetic and morphological properties and features that create relevant conditions for the development and growth of plants.

conclusions

So, if we return from Mars to the sinful Earth and consider any one and the same patch of lawn from the point of view of terms that interest us, then the following immediately becomes obvious:

Looking at it as a "soil", we consider it primarily from an engineering-mechanistic (economic) point of view (most often as a potential object in engineering and construction activities).
Considering it as “soil”, we are primarily interested in its fertility relative to the plant that will be grown on it in the future (it is important to understand that the requirements for different plants soil fertility can be different and generally highly specific).

Soil is a special natural body formed on the surface of the Earth as a result of the interaction of living (organic) and dead (inorganic) nature. The most important property soil, which distinguishes it from rocks, is fertility. It is due to the presence of humus or humus in the soils. Soil fertility is the greatest natural wealth which must be used very wisely. Soils are formed very slowly: in 100 years, the thickness of the soil increases by 0.5 - 2 cm.

Soil formation factors

An outstanding Russian scientist - the founder of the science of soil (soil science) V.V. He wrote that the soil is a "mirror" of nature. , climate, water, microorganisms, plants and animals are involved in the formation of soils. Among these factors special place occupies human activities.
Soil structure. The formation of soils involves the processes of humus formation and the movement of organic matter, and the formation of humus and the movement of organic and mineral compounds within the soil profile.

The upper horizon is humus. It is densely permeated with roots. Here there is an accumulation of organic matter and the formation of humus. The humus horizon is the darkest. Its color depends on the accumulated humus. The amount of humus decreases from top to bottom, so the horizon is lighter in the lower part. When precipitation falls and snow melts, moisture seeps through the humus horizon, which dissolves and removes part of the organic and mineral compounds from it. In soils formed under conditions of large , a leaching horizon is formed under the humus horizon.

This is a very clarified horizon, from which a significant part of organic and mineral compounds has been removed.

Sometimes everything that can dissolve is taken out, and only silica remains. This is a podzolic horizon.

Below lies the washout horizon. He gets what he loses top part soil. Below it is a slightly altered parent rock, on which the process of soil formation initially began. Between there is a continuous exchange of matter, through the circulation of the soil solution.

According to the structure of the soil profile, i.e. according to the degree of expression of individual horizons, their thickness and chemical composition, they determine whether the soil belongs to a certain type.

According to the mechanical composition - the ratio of mineral particles of various sizes (sand, clay), soils are divided into clay, loamy and sandy.

The structure of the soil, the ability of soil particles to combine into relatively stable lumps, contributes to maintaining a favorable water and air regime for plants. The shape, the size of the lumps is not the same in different types soils. The best is a granular, or small-lumpy, structure with lumps with a diameter of 1 - 10 mm. If there is little humus and clay particles, then such soils are usually structureless (sandy and often sandy).

Diversity and placement of soils

The type, mechanical composition, structure of the soil, its fertility, etc., depend on the combination of factors of soil formation under specific conditions. The location of soils on Earth depends primarily on. there is a change of soils, and in the mountains - from the foot to the peaks.

In conditions of the same climate, the diversity of soils is due to relief and rocks. Each territory has its own combinations of soils with certain properties. The main types of soils common in Russia are: tundra-gley, podzolic, gray forest, chestnut.

It took nature several billion years to ensure that the soil of the Earth acquired the properties due to which vegetation could appear on our planet. At first, instead of soil, there were only rocks, which, due to the impact of rain, wind, and sunlight on them, began to gradually grind.

Soil destruction occurred in different ways: under the influence of the sun, wind and frost, stony rocks cracked, polished with sand, and sea waves slowly but surely, they broke huge blocks into small stones. Finally, animals, plants and microorganisms made their contribution to the formation of the soil, adding organic elements (humus), enriching the upper layer of the earth with waste products and their residues. The decomposition of organic elements when interacting with oxygen led to various chemical processes, as a result of which ash and nitrogen were formed, which turned rocks into soil.

Soil is a modified loose upper layer of the earth's crust on which vegetation grows. It was formed as a result of the transformation of rocks under the influence of dead and living organisms, sunlight, precipitation and other processes due to which soil erosion occurred.

Due to this transformation of huge, hard rocks into a loose mass, the topsoil acquired an absorbent surface: the soil structure became porous and breathable. The main significance of the soil is that, being penetrated by the roots of plants, it gives them all the nutrients necessary for growth, and combines two features necessary for the existence of plants - minerals and water.

Therefore, one of the main characteristics of the soil is a fertile soil layer, which allows for the growth and development of plant organisms.

In order for a fertile layer of soil to form, the earth must contain a sufficient amount of nutrients and have the necessary supply of water that would not allow plants to die. The value of land largely depends on its ability to convey to the roots of plants nutrients, provide them with access to air and moisture (water in the soil has an extremely importance: nothing will grow if there is no liquid in the earth that will dissolve these substances).

The soil consists of several layers:

The arable layer is the top layer of soil, the most fertile soil layer, which contains the most humus;
Subsoil - consists mainly of the remains of rocks;
The lowest layer of soil is called the "bedrock".

Soil acidity

A very serious factor that affects the fertility of the soil is the acidity of the soil - the presence of hydrogen ions in the soil solution. The acidity of the soil is increased if the pH is below seven, if it is higher - alkaline, and equal to seven - neutral (the concentration of hydrogen ions (H +) and hydroxides (OH-) is the same).

The high level of acidity of the upper layer of the earth negatively affects the growth of plants, since it affects its characteristics (size and strength of soil particles), applied fertilizers, microflora and plant development. For example, increased acidity disrupts the structure of the soil, since beneficial bacteria cannot develop normally, and many nutrients (such as phosphorus) become difficult to digest.

Too high a level of acidity makes it possible to accumulate in the soil toxic solutions of iron, aluminum, manganese, while the intake of potassium, nitrogen, magnesium, and calcium into the body of plants decreases. main feature high level acidity is the presence of a light layer under the upper dark layer of the earth, resembling ash in color, while the closer this layer is to the surface, the more acidic the soil and the less calcium it contains.

Soil types

Since absolutely all types of soils are formed from rocks, it is not surprising that soil features largely depend on chemical composition And physical characteristics parent rock (minerals, density, porosity, thermal conductivity).

Also, the characteristics of the soil are affected by the conditions under which the soil was formed: precipitation, soil acidity, wind, wind speed, soil temperature and environment. The climate also has an indirect effect on the soil, since the life of the flora and fauna directly depends on the temperature of the soil and the environment.

Soil types depend largely on the size and number of particles that are present in them. For example, damp and cold clay soils are formed by sand particles tightly adjacent to each other, loamy soil is a cross between clay and sand, and stony soil contains a lot of pebbles.

But the composition of peat land includes the remains of dead plants and it contains very few solid particles. Any soil on which plant organisms grow has a very complex structure, since, in addition to rocks, it contains salts, living organisms (plants), and organic substances that were formed as a result of decay.

After the soil analysis was done in different regions of our planet, a classification of soils was created - a set of sites of the same type that had similar conditions for the formation of soil. The classification of soils has several directions: ecological-geographical, evolutionary-genetic.

In Russia, for example, the ecological and geographical classification of soils is mainly used, according to which the main types of soil are soddy, forest, podzolic, chernozem, tundra, clayey, sandy, steppe soils.

Chernozem

Chernozem, which has a lumpy or granular structure, is considered the most fertile soil (about 15% humus), characteristic of a temperate continental climate, in which dry and wet periods alternate, and positive temperatures predominate. Soil analysis showed that the chernozem is rich in nitrogen, iron, sulfur, phosphorus, calcium and other elements necessary for the favorable life of plants. Chernozem soils characterized by high water-air characteristics.

sandy lands

Sandy soil is typical for deserts and semi-deserts. It is a crumbly, granular, non-cohesive soil in which the ratio of clay to sand is 1:30 or 1:50. It poorly retains nutrients, moisture, and due to the poverty of the vegetation cover, it is easily susceptible to wind and water erosion. Sandy soil also has advantages: it does not swamp, since water in the soil easily passes through the coarse-grained structure, air enters the roots in sufficient quantities, and putrefactive bacteria do not survive in it.

forest land

Forest soils are characteristic of the forests of the temperate zone of the northern hemisphere and their properties are directly dependent on the forests that grow in it and have a direct impact on the composition of the soil, its air permeability, water and thermal regimes. For example, deciduous trees have a positive effect on forest soils: they enrich the soil with humus, ash, nitrogen, neutralize acidity, creating favorable conditions for the formation of beneficial microflora. And here conifers trees render on forest soil Negative influence, forming a podzolic soil.

Forest soils, no matter what trees grow on them, are fertile, since nitrogen and ash, which are in fallen leaves and needles, return to the ground (this is their difference from the land of fields, where plant litter is often taken out along with the crop).

Clay lands

Clay soils contain about 40% clay, are damp, viscous, cold, sticky, heavy, but rich in minerals. Clay soil has the ability to retain water for a long time, they are slowly saturated with it and very slowly pass it into the lower layers.

Moisture also evaporates slowly - this makes it possible for plants growing here to suffer less from drought.

The properties of clay soil do not allow the root system of plants to develop normally, and therefore most of the nutrients remain unclaimed. In order to change the composition of the top layer of the earth, it is necessary to apply organic fertilizers for several years.

Podzolic land

Podzolic soils contain from 1 to 4% humus, which is why they are characterized grey colour. Podzolic soil is characterized by a very low content of nutrients, high acidity, and therefore it is infertile. Podzolic soils usually form near temperate coniferous and mixed forests, and their formation is strongly influenced by the predominance of precipitation over evaporation, low temperatures, reduced activity of microbes, poor vegetation, due to which podzolic soils are characterized by a low content of nitrogen and ash (for example, soils of the taiga, Siberia, the Far East).

To use podzolic soils in agricultural work, farmers need to make a lot of efforts: to introduce large doses of mineral and organic fertilizers, constantly regulate the water regime, plow the land.

Soddy soil

Soddy soils are fertile and characterized by a low or neutral level of acidity, a high amount of humus (from 4 to 6%), and also soil properties such as water and air permeability are inherent in them.

Soddy soils are formed under a developed herbaceous cover, mainly in meadows. Soil analysis showed that turf land contains big number magnesium, calcium, ash, and humus contains a lot of humic acids, which, during the reaction, form humates - insoluble salts that are directly involved in the formation of the lumpy-granular structure of the soil.

tundra land

Tundra soils are poor in minerals and nutrients, very fresh and contain little salt. Due to low evaporation and frozen ground tundra soils are characterized high humidity, and due to the insufficient amount of vegetation and its slow humification, the humus content is low. Therefore, tundra soils contain a thin peaty layer in their upper layer.

The role of the soil

The importance of soil in the life of our planet is difficult to overestimate, since it is an indispensable element of the earth's crust, which ensures the existence of plant and animal organisms.

Since a large number of very different processes flow through the upper layer of the earth (among them the cycle of water and organic substances), it is a connecting link between the atmosphere, lithosphere and hydrosphere: it is in the upper layer of the earth that chemical compounds are processed, decomposed and transformed. For example, plants that grow in the ground, decomposing together with other organic substances, are transformed into minerals such as coal, gas, peat, and oil.

The protective functions of the soil are also important: the earth neutralizes the substances that are hazardous to life (this is especially important, since recently soil pollution has become catastrophic). First of all, these are toxic chemical compounds, radioactive substances, dangerous bacteria and viruses. The margin of safety of the top layer of the earth has a limit, therefore, if the pollution of the soil continues to increase, then it will cease to cope with its protective functions.

Useful solutions for growing plants are made by mixing ordinary earth with various additives (other types of earth, sand, etc.).

For flowers growing in pots, the roots take up quite a bit of space, and they grow up to small size, therefore, in the earth there should be a lot of substances useful for the plant.

1. Sod land(also known as Soddy Earth), it is added to many earthen solutions. It has a lot of different components useful for flowers. Among the shortcomings, one can note its predisposition to tamping.

2. leaf humus(also known as leafy or leafy ground). It turns out such a land as a result of the debate of crumbling leaves. She has a lot useful components, her distinctive features: lightness, disposition to loosening. This type of land is used for growing flowers that do not tolerate humus consisting of manure. This type of soil is stored from the forest, taking away the surface layer of the earth. The accumulated foliage is stacked in piles, up to one and a half meters high, it is all moistened with liquefied manure, and after two years such soil is ready for use.

3. Sand from rivers, it performs the function of loosening the earth. It is preferable to use sand consisting of large grains of sand. Also, it improves the quality of clay soils.

4. manure humus. Such land is formed as a result of mixing rotten manure and humus from greenhouses. As well as compost, it is laid in heaps. The peculiarity of this earth is that it is very crumbly, soft and moisture-intensive, it enhances the quality of earth mixtures.

5. peat humus- This is a crumbly, airy, well-absorbing mass of the flag, which is formed due to the decay of marsh peat. This mass improves the properties of the earth. Adding it to the ground increases its subacidity, so you should carefully monitor the level of acid, both the added mass and the earth to which it is added, and in which case, dilute the earth with a mixture of limestone and chalk.

6. Sphagnum, it is mixed with the earth to increase its airiness, friability and ability to absorb water vapor from the air. It is worth noting that before adding, sphagnum must be passed through a sieve. Soil mixed with sphagnum is suitable for growing lilies of the valley and orchids.

Classification of earth solutions

Thus, in order to make useful earthen solutions, one must consider the planting conditions of the various flowers for which they are made. However, it is very difficult to study the requirements for each plant, which is why earth solutions are classified for similar, according to planting conditions, plants:

heavy mortar. Consists of five components. The first three are the earth from cut sod, the fourth is humus, the fifth is river sand
Medium weight solution. It is made from two portions of earth from cut sod, two portions of leafy humus, two portions of ordinary humus and one portion of coarse sand from rivers.
Light weight solution. It is prepared from one portion of soddy soil, three parts of leaf humus and one portion of river sand.

Based on high-moor peat (decayed sphagnum moss that grows on raised bogs) - contains a minimum amount of minerals, is breathable, has good water absorption and moisture retention. This substrate is often used as a temporary soil for the transport of plants, as well as for the sale of potted plants.

Based on lowland peat (extracted from lowland swamps, lakes and rivers) - characterized by the presence a large number mineral substances, retains moisture well. However, it quickly cakes, dries out for a long time, as a result, the roots of plants often rot. Soil based on lowland peat is used as a component of the soil mixture prepared independently, but not as an independent substrate.

Based on biohumus (a product of manure processing by earthworms) - rich in organic matter and living organisms. Such soil is used as a component of the soil mixture for its enrichment. Biohumus is an alternative to humus.

Special primer for indoor flowers

For orchids- a mixture of peat, charcoal, crushed pine bark, sphagnum moss. For epiphytes, not soil is used, but pieces of pine bark or driftwood wrapped in sphagnum moss.
For azaleas- high-moor peat, needles, sand. The soil is moderately acidic and loose, with a low content of nutrients.
For palm trees- a soil mixture of high-moor peat, leaf and sod land, sand. The soil is nutritious, with a neutral reaction.
For cacti- sand, leafy soil or high-moor peat, depending on the group of cacti (there are forest and desert ones).
For violets– high-moor peat, sand, coniferous soil, charcoal, moss-sphagnum.
For ferns- peat, sand, humus.

But do not think that ready-made mixtures for the plants mentioned above are ideal. There are many species of the same genus that naturally grow in different conditions. Therefore, acquiring ready ground it must be supplemented with components necessary for a particular type of plant.

Some specialized soils are suitable for growing other types of plants. Typically, this information is indicated on the packaging.

What to look for when choosing a finished soil

Primer for flowers:

must pass air;
must be nutritious;
should not retain moisture for a long time;
should not contain pests and pathogens;
soil acidity should correspond to the level that is needed specific type plants.

Thus, it is necessary to approach the choice and preparation of the land responsibly, because certain types of plants require a certain soil, otherwise the wrong choice of land can lead to the death of the plant, or in any case, the flower can get sick or lose its properties.