Depending on the conditions of formation, chernozem soils are divided into the following subtypes: podzolized, leached, typical, ordinary, southern and mycelial-carbonate.

Podzolized and leached chernozems formed in the forest-steppe zone under meadow steppe vegetation. In podzolized chernozems there are traces of podzolization in the form of a siliceous powder, the humus layer is somewhat lightened and has a slightly acidic reaction due to the content of a small amount of H+ ions in the absorbed state; there are no carbonates in the first meter of the soil profile. Leached chernozems do not have siliceous powder, but the carbonates in them are carried beyond the horizon.

Typical chernozems formed under steppe forb vegetation. They have the best properties and characteristic profile structure inherent in chernozem type soils.

Ordinary and southern chernozems develop in a drier climate under steppe fescue-feather grass vegetation. They have a humus horizon that is thinner than that of typical chernozem. An accumulation of carbonates is noted directly under the humus layer in the form of white eyes. Southern chernozems, unlike ordinary chernozems, contain up to 5% sodium in the absorbed complex and are characterized by a weak herringbone reaction and the manifestation of signs of solonetsity.

Mycellar-carbonate chernozems are formed in a humid climate with a long warm period. They have a humus horizon of maximum thickness, but with a low humus content of 4-6%. They are characterized by the content of carbonate compounds, starting from the surface layer.

Chernozems are divided into types depending on the humus content and the thickness of the humus layer.

Depending on the humus content they distinguish the following types chernozems: fat - more than 9%, medium-humus - from 6 to 9, low-humus - from 4 to 6, humus - up to 4%. According to the thickness of the humus layer, chernozems are classified as super-deep (more than 120 cm), powerful (80-120 cm), medium-deep (40-80 cm), thin (25-40 cm) and thin shortened (less than 25 cm).

In lower relief elements with close groundwater (2-5 m and above), soils of the meadow-chernozem type are formed, similar in properties to chernozems, but with a noticeable manifestation of gleyization processes.

Agricultural use of chernozem soils and ways to increase their fertility. Currently, almost all areas of chernozem soils are in agricultural use. More than half of all crops are concentrated here.

The most important task of agriculture- preservation and increase of natural fertility of chernozem soils. This is achieved by implementing a set of agrotechnical measures, the implementation of which should take into account both natural conditions, as well as natural and acquired properties of chernozems. The main attention should be paid to techniques aimed at improving their water regime.

It has been established that long-term extensive use of chernozems leads to a significant decrease in the humus content in them. According to calculated data, the average annual loss of humus in typical and leached chernozems on average over 100 years amounted to 0.7-0.9 t/ha, in ordinary chernozems - 0.5-0.7 t/ha.

To increase the humus content in chernozems, it is necessary to apply complex events . These include enriching the soil with organic matter (applying organic fertilizers, sowing perennial grasses, leaving higher stubble of grain crops), applying mineral fertilizers, minimizing processing, creating optimal ratios crop rotations to replenish the soil with organic matter and enhance the process of humification, the use of ameliorants (lime, defecation, gypsum, etc.), causing the fixation of humus on the surface of the mineral part of the soil.

Characterized by high potential fertility, chernozems contain insufficient quantity easily accessible to plants nutrients. Therefore, it is necessary to apply fertilizers to these soils, as well as to activate the activity of soil microflora in them.

To improve the agrophysical properties of chernozems, their lost natural structure should be restored and preserved. This is achieved by mastering crop rotation, sowing perennial grasses, applying various organic fertilizers, correct processing soil.

Chernozem is not only a type of soil that is rich in humus, has dark color and granular structure, and also due to its high fertility, it is actively used in agriculture. This natural resource is one of the largest carbon stores in the world, home to almost a third of living organisms and is subject to restoration, because it takes more than 1000 years to form 1 cm of soil.

The formation of the described type of soil occurs under perennial herbaceous vegetation in such natural zones as steppe and forest-steppe, located in conditions of a temperate continental type of climate.

Due to their granular structure, chernozems are characterized by excellent air permeability, as well as a humus content of up to 15%. Also, such important elements for plant nutrition as nitrogen, iron, phosphorus and others accumulate in the soil and are fixed in the form of mineral compounds of organic origin. In addition, the calcium content varies from 70 to 90%, which in turn ensures neutral reactions.

Depending on the place of formation, the thickness of the humus layer and the percentage of humus to chernozem, the described type of soil has several gradations.

Modern classification distinguishes 5 subtypes of chernozem - leached, podzolized, ordinary, southern and typical.

Leached chernozems are formed in the steppes under cereals and herbs. Broad-leaved forests, rich in herbaceous vegetation, serve as a place for the formation of podzolized chernozems. Ordinary chernozem is formed in steppes with forbs located in the northern regions. Southern chernozem can be found in the southern parts of the steppe, rich in fescue-feather grass vegetation. Cover and loess-like loams, covered with cereals and forbs, serve as a place for the formation of typical chernozems.

Based on the depth of humus (thickness of the humus layer), 4 groups are distinguished: low-thick (less than 0.4 m), medium-thick (from 0.4 to 0.8 m), powerful (from 1.2 to 0.8 m) and heavy-duty ( more than 1.2 m).

Classification of chernozem according to the percentage of humus content distinguishes 5 groups, which are characterized by their own soil color. Rich or highly humus soil has more than 9% humus and is colored deep black. Medium humus soils are black in color and the percentage of humus varies from 6 to 9. gray characteristic of low-humus soil with a humus content of 4 to 6%. Low-humus soils are gray in color; the humus content in these soils is less than 4%. Microhumus soils contain less than 2% humus and are light gray in color.

Option 2

Under the steppe landscapes of Eurasia, North America(prairie) and South America(pampa) there are chernozem soils with high quality fertility. These are due to the presence of humus, formed from the remains of plant cover.

Soil formation conditions.

The temperate climate zone is characterized by annual temperatures up to +7 0 C, with annual precipitation from 300 to 600 mm.

The vegetation cover is represented mainly by cereal crops and herbaceous forms of life. Decomposition occurs in the upper soil layer plant residues under the influence of climatic conditions and bacteria. In addition to organic matter, inorganic substances are formed in the soil: nitrogen, phosphorus, sulfur and iron. The soil horizon becomes black.

Profile:

A – humus horizon (thickness 40-120 cm);

B – transition horizon;

C – mother breed.

Soil properties:

• the structure is lumpy, granular;
• 70-90% Ca in horizon B;
• neutral chemical reaction;
• 15% humus content in horizon A (the classification marks the highest degree of fertility in the southern subtype, which allows for excellent harvests).

Soil color:

The whitish color is formed as a result of intensive leaching of mineral products. The process of formation of solonchaks and solonetzes begins. You can determine the presence of kaolin, gypsum and magnesium in the composition.

Study of black soils:

1. M.V. Lomonosov, essay “On the Layers of the Earth,” 1763. The concept of “chernozem” was introduced.

2. M. I. Afonin collected soil samples for exhibition in museums in 1771.

3. V. M. Severgin “Detailed mineralogical dictionary” 1807

4. The greatest contribution to the science of soil science was made by V.V. Dokuchaev, who spent the years 1876-1882 in scientific works. Compiled detailed description and classification of chernozems. He wrote “Russian Chernozem” in 1883.

5. In the French capital of Paris in 1889, an exhibition was held where the “black soil” exhibit was shown.

It is worth noting that the formation of a fertile humus horizon took hundreds of years. It takes much less time to lime it. Thus, in the steppes of North America, intensive development of chernozems led to dust storms in the 20th century.

INTRODUCTION

Russia contains more than 10% of the world's farmland. According to media reports, our country remains the last large reserve of agricultural land on the planet, at least in the “civilized” world. Therefore, knowledge about our land resources suitable for agriculture has recently become of utmost importance. According to the founder of Russian soil science V.V. Dokuchaev, “our plant-terrestrial soils (of which chernozem is a representative) are not some kind of mechanical, random, lifeless mixtures, but, on the contrary, are independent, definite, natural-historical bodies subject to known laws” (1).

1. CHARACTERISTICS OF CHERNOZEM

Compound

Chernozem is a rather heterogeneous mass: here you can find pieces of quartz, flakes of humus, and sometimes fragments of limestone, feldspar and even granite pebbles.

It is very rich in humus (dark organic matter, one might say, natural manure) and the most important, easily soluble plant nutrients, such as: phosphoric acid, nitrogen, alkalis, etc. Typical chernozem is usually fine-grained, crumbly and always reveals the closest family connection(both in structure and composition) with underlying rocks (subsoil), which themselves (loess) in the vast majority of cases are very rich in soluble nutrients and endowed with excellent physical properties.

Structure

Chernozem is a plant-terrestrial soil whose thickness on average is about 60 cm. Under the turf, 5-8 cm thick, there is a dark, homogeneous, loose mass - humus, consisting of grains or grains, sometimes roundish, but more often representing irregular polyhedra. This horizon in uncultivated, virgin places is overcrowded with hundreds of thousands of living and dead underground parts herbaceous plants. The average thickness of the A horizon (accepted designation according to V.V. Dokuchaev) is 30-45 cm. Below, the soil horizon merges completely imperceptibly with the transition horizon, which indeed, in all its features (physical and chemical), represents a gradual transition from the upper (A) horizon to the lower (C) subsoil. The thickness of horizon B is also 30-45 cm. The subsoil - the base (C) in the vast majority of cases consists of loess (light yellow, very loose, carbonate-rich loam), but often it also consists of sandy loam, chalk, limestone, marl, etc. ., and always the subsoil (C) gradually passed into the upper soil horizons (A and B), giving them a strictly defined mineral character. Thus, chernozem in all natural sections, not disturbed (in one way or another) represents a gradual, closest genetic connection with the subsoil, whatever its composition.

Types

The following subtypes of chernozem soils are distinguished:

Podzolized chernozems,

Leached chernozems,

Typical chernozems,

Ordinary chernozems,

Southern chernozems.

Properties

1. Due to its composition, chernozem always has more or less dark color and relates favorably to heat and moisture. Color is a typical external feature: the color of chernozem, whether it contains humus up to 15% or no more than 3-4%, always turns out to be more or less dark,

2. Replenishment of chernozem, that is, the ability to become much more ripe (in the agricultural sense), that is, one whose subarable horizon is approximately the same composition in structure as the arable one.

3. Another typical constant feature is the average thickness of chernozem, which ranges from 60 to 140 cm.

2. AREAS OF DISTRIBUTION

According to V.V. Dokuchaev chernozem is always and everywhere the result of combined activities:

a) bedrock (subsoil), on which it currently lies;

b) the climate that surrounds this soil now and surrounded it in the past (latitude and longitude, the nature of precipitation, temperature, winds);

c) wild vegetation that grew there and still grows to this day in places untouched by culture.

The areas of distribution of fertile plains in the world are: the steppes of Europe and Asia, the savannas of Africa, Australia, the prairies of North and Pampas of South America, Venezuela, Brazil.

On the territory of Russia, chernozems are distributed in the regions of the Volga region, the Urals, the North Caucasus, the Lower Don and Western Siberia. The heart of the black earth strip is the Voronezh and Saratov regions. The volume of chernozem soils in the world is 48%, in Russia - 8.6%, which is 1.53 million km 2.

3. APPLICATION

Chernozem soils can withstand long-term cultivation without any fertilizer and, whenever climatic conditions are favorable, they produce excellent harvests rice, grains, sunflowers, beets, feed, fruits, grapes and other technical and vegetable crops. The natural fertility of chernozem soils makes it possible to fully satisfy the population's need for food, provides a significant part of the raw materials for light industry, and ensures livestock breeding.

Farmers value chernozem for its natural humification and mineralization, the formation of colloidal organic components, humic and fulvic acids, microelements, and nutrients. They accelerate the development of plant root systems and soil microorganisms, and improve soil quality.

It is distinguished by its dark brown and black shades, a greasy mark on the palms after squeezing the lump, and a long drying time after rain.

The only drawback of the soil is its waterproof, lumpy, granular structure.

However, dense chernozem does not sinter in extreme heat and is protected from through wetting and erosion.

Benefits of black soil

The main characteristics showing the level of fertility of this soil:

• Special soil structure
• Neutral acidity level
• High percentage of humus content (up to 15%)
• A large amount of nutrients, calcium, as well as microorganisms present in the soil

How are black soil formed?

To create a humus profile, certain weather, biological and geological conditions are required.

1. Continental slightly arid climate with average annual values ​​of +3...+ 7 °C and precipitation of 350-550 mm.
2. Moderate moisture evaporation up to 25%.
3. Consecutive drying and moistening of the soil.
4. Growth of dense vegetation with powerful roots.
5. Underlying rock with an alkaline earth surface.

In Hungary, Romania, and the eastern part of Austria, chernozem appeared in the post-glacial period and is considered relict. Today, in Russian steppe and forest-steppe zones, fertile soil is formed by humus of plants. Play a significant role groundwater, improving its properties. Of these, tree roots:

• absorb nutrients;
• soak the earthen lump;
• break it down into aggregates;
• improve air circulation and loosen the soil;
• accelerate decay.

The soil is nourished by organic residues in the amount of 12-15 t/ha calculated on dry matter. With leaf litter, it receives 700-1100 kg of nitrogen and ash substances with minerals.

Typical black soil profile

During soil formation, humus-accumulative horizons are formed, which differ in cross-section in shades, structure, chemical composition. Each has a name and designation. Transitions between horizons and the shape of boundaries determine the morphological characteristics of the soil. Chernozem has horizons with a thickness of 60-100 (180) cm.

1. A0 – surface layer (3-5 cm) with a uniformly colored structure.
2. A – dark granular or lumpy (30-50 cm) made of humus with browning towards the bottom.
3. AB (10–60 cm) is a brown-colored humus-transition horizon with a wicked tongue-like border, subdivided into clayey and carbonate half-horizons.
4. Vk-Sk is transitional to the parent rock.

The soil profile varies depending on the geographical direction. The north is characterized by leached chernozems. Acidic forest humus quickly decomposes, forms a different structure and weakens the thickness of the horizon. Dispersed humic acids due to the iron content give it a darker color. Southern soils contain less humus and more carbonates, which stop oxidation.

Classification of chernozems

Chernozem soil is divided into subtypes:

• Podzolized with a siliceous structure and a whitish powdery powder are formed in the forest-steppe zone under meadow vegetation. The humus content ranges from 5–12%. The reaction of the top layer is close to neutral.
• Leached soils are formed from forb-grass flora. The properties are similar to podzolized ones, but do not have silica powder. Carbonates are located beyond the horizon.
• They have the best characteristics typical And h humus of steppe forbs. The concentration of organic matter sometimes reaches 18%.
• Ordinary And southern layers are formed in dry weather from fescue-feather grass steppe plants. They contain a thinner horizon and 4-7% humus.
• Micellar-carbonate prefer a humid, warm climate. They differ in carbonate content and a strong humus horizon. The percentage of humus is 4-6%.

Features of using black soil at the dacha

In order to grow crops in the garden and not disturb the ecosystem, certain rules are followed.

There is no need to replace all the soil with black soil and refuse fertilizers.

Without replenishing nutrients, the land quickly becomes depleted.

The removal of clay particles, aluminum, calcium and iron oxides by water from the upper layers leads to a decrease in the concentration of humus in the upper layer and a decrease in yield.

A serious mistake is excessive application of soil for vegetables and flowers.

Chernozem is formed at temperatures above +5 degrees, and also subject to an annual intake of up to 600 mm. Chernozem soil deposits are located on an undulating-plain topography, characterized by the presence of river terraces, ravines or depressions in some places.

The peculiarity of chernozem soil is that it grows large number meadow and steppe plants. The decomposition of such vegetation leads to the formation of humus, which gradually accumulates in the upper layers of the soil. Chernozem also contains other substances: organic and mineral compounds that make it possible to obtain phosphorus, nitrogen, sulfur and other components that nourish the soil.

Properties

A distinctive feature of chernozem is its structure; it is a granular-lumpy mixture. This soil contains a lot of potassium. Chernozem is also characterized by special water-air qualities. Farmers value it for its excellent fertility associated with a high percentage of humus in the upper layer. This soil contains up to 15% humus.

Types of black soil

There are 5 main types of black soil:

• Leached is formed in the forest zone due to the death of cereal plants;
• Podzolized forms in broad-leaved grassy forests;
• The common one is present in the steppe zone, and is formed after the death of forb plants;
• The typical type is formed on loams, in forest-steppe regions, meadow-steppe zones during the decay of forbs and cereal crops;
• The southern one can be found in the southern part of the steppe zones, and its formation is associated with the death of fescue-feather grass vegetation.

Application of chernozem

This is the most fertile type of soil, which is actively used in gardening, horticulture, and agriculture as fertile land for growing plants, herbs, shrubs and trees. Chernozem is used in the cultivation of lands that contain a lot of clay, to dilute soils that are characterized by poor drainage system to create an air-water regime favorable for plant growth.

Chernozem is sold in bags or bags of any size. You can order black soil in bulk from our company. Delivery is carried out in Moscow and the Moscow region on the day of order.