Soils of the East European Plain. East European Plain: its rivers and lakes

Introduction........................................................ ........................................................ ....... 2

1. Factors of soil formation on the East European Plain.................................. 3

1.1 Climate................................................... ........................................................ ..... 3

1.2 Water mode................................................... ............................................... 3

1.3 Plant cover and fauna............................................................ ........ 5

2. Genesis and classification of chernozem soils.................................................... .. 9

2.1 Genesis of chernozem soils.................................................... ......................... 9

2.2 Classification of chernozem soils.................................................... .......... eleven

3. Composition and properties of chernozem soils.................................................... .......... 17

3.1 Mechanical and mineralogical composition.................................................... 17

3.2 Physico-chemical properties of chernozem soils.................................................. 17

4. Economic use of chernozem soils.................................................. 22

Chernozems have been the object of research since the very beginning of soil science. Also M.V. Lomonosov (1763) formulated the position about the origin of chernozem “from the decay of animal and plant bodies over time.” After M.V. Lomonosov, there was a gradual accumulation of factual material about the properties and distribution of chernozems; a number of interesting theories about their origin were put forward.

The truly scientific study of chernozems began with V.V. Dokuchaev, who collected enormous material on the structure, properties, distribution and conditions of formation of Russian black soil. As a type of soil, chernozem was first identified by V.V. Dokuchaev in the classification of soils in 1896.

The first fundamental studies of the water-physical properties and water regime of chernozems were carried out by A.A. Izmailsky and G.N. Vysotsky at the end of the 19th and beginning of the 20th century.

The climatic conditions of the chernozem distribution zone are characterized by increasing continentality from west to east. In the southwest of the East European Plain, the average annual temperature is 8-10 C. Winter in the western regions of the zone is relatively warm and mild, to the east it becomes more severe and with little snow. Also, from west to east, the number of frost-free days and the annual amount of precipitation decreases.

However, during the warm period, the climatic contrasts of different regions are smoothed out.

The yield of agricultural crops in the chernozem zone is determined primarily by the content of moisture available to plants in the soil. This is an area of ​​insufficient moisture. Even in the forest-steppe, the probability of dry and semi-arid years is about 40%.

Therefore, throughout the history of the study of chernozems, special attention was paid to the study of their water regime.

A.A. studied the water regime of chernozems. Izmailsky, G.N. Vysotsky, P.A. Kostychev, S.I. Dolgov, A.F. Bolshakov, A.A., Rode, E.A., Afanasyeva, etc.

Studying the water regime of ordinary chernozems, G.N. Vysotsky established that in the dynamics of moisture in chernozems, two periods can be distinguished: 1) drying out of the soil, covering the summer and the first half of autumn, when moisture is intensively consumed by plants and evaporates due to the dominance of ascending flows over descending ones; 2) soaking, starting in the second half of autumn, interrupted by frosts and continuing in the spring due to warm waters and spring precipitation.

These periods in the water regime of chernozems and its features are characteristic of all chernozems, however, the duration and timing of drying and wetting will be different for each subtype. They are determined primarily by the amount of precipitation, its distribution over time and temperature. The general pattern is a decrease in the depth of soil wetting from podzolized and leached chernozems to southern chernozems and an increase in soil drying in the same direction as the drying period lengthens.

Summer precipitation only moistens the arable layer. The moisture reserve in the lower horizons of chernozems is created by precipitation of the cold period (late autumn precipitation, melt water). In subzones, the moisture content of chernozem soils largely depends on the topography and mechanical composition of the soil. Light loamy and sandy loamy chernozems are soaked to great depths. On convex relief elements and slopes, moisture consumption increases due to surface runoff and evaporation; in depressions, especially concave and semi-closed ones, surface water accumulates and evaporation is weakened, which determines deeper soil wetting. In closed depressions it can reach groundwater.

The water regime of steppe chernozems differs from that of steppe zone chernozems. Podzolized, leached and typical chernozems are characterized by periodically leaching water regime.

The lower horizons of the soil-ground layer of forest-steppe chernozems, deeper than the layer of maximum wetting, always contain a certain amount of available moisture, which can serve as a moisture reserve in dry years.

The water regime is much more intense in the steppe zone (ordinary and southern chernozems), which are classified as arid and semi-arid. The chernozems of the steppe zone have a non-percolative water regime: in the lower part of their soil layer a constant horizon is formed with a moisture content not exceeding the wilting moisture content.

To obtain average yields of agricultural crops, the meter layer of soil before sowing must contain at least 1000 t/ha of available moisture. Therefore, all agrotechnical measures should be aimed at maximizing the restoration of the reserves of moisture useful for plants in the entire root layer of the soil by the spring of next year.

On arable chernozems, compared to virgin soils, a significant loss of water is possible due to snow drift and surface runoff of melt water. Blowing away snow leads to deep freezing of soils, so they later freeze. A sharp decrease in the water permeability of unthawed soil layers is accompanied by large losses of moisture from surface runoff.

Chernozems are soils of herbaceous formations confined to the steppe and forest-steppe zones. The characteristic humus profile is due to the influence of herbaceous vegetation with its powerful, rapidly dying root system.

The natural vegetation of the forest-steppe zone in the past was characterized by alternating forest areas with meadow steppes. Forest areas, partially preserved to this day, are located along watersheds, ravines and river terraces, and are represented by broad-leaved forests, mainly oak. Along the sandy terraces there are pine forests. The vegetation of the meadow steppes included feather grass, fescue, steppe oats, brome, sage, commonweed, yellow alfalfa, bluebell and many others.

The vegetation of the steppe zone consisted of forb-feather grass and fescue-feather grass steppes.

Among the former, the main background consisted of narrow-leaved turf grasses - feather grass, fescue, steppe oats, and others with a wide participation of forbs - sage, clover, bluebells, etc.

Fescue-feather grass steppes were characterized by less powerful and diverse vegetation, the main representatives of which were low-stemmed feather grass, tyrsa, fescue, wheatgrass, and sedges. The less powerful general character of the vegetation of the fescue-feather grass steppes, the widespread participation of ephemerals and ephemeroids in the grass stand - mortuk, bulbous bluegrass, tulips, alyssum, as well as wormwood - is a consequence of a noticeable moisture deficit here.

The main features of the biological cycle of steppe and meadow-steppe herbaceous plant communities are that: 1) annually, with dying parts, almost the same amount of nutrients that was used in growth is returned to the soil; 2) most of these substances return not to the soil surface, but directly into the soil with the roots; 3) among the chemical elements involved in the biological cycle, the first place belongs to silicon, followed by nitrogen, potassium and calcium.

The amount of plant mass of natural grass communities on chernozems is high: in the forest-steppe of the Russian Plain 30-40 c/ha of above-ground phytomass and 200 c/ha of roots. The annual increase in phytomass on chernozems is 1.5-2 times higher than the amount of biomass during the period of maximum development. The growth of roots accounts for 50-60% of their total mass. On average, the litterfall of herbaceous communities in the chernozem zone is 200 c / (ha per year) (A.A. Titlyanova, N.I. Bazilevich, 1978).

The role of the biological cycle in the formation of the properties of chernozems is determined not so much by the chemical composition of steppe plants, but by its high intensity (a large number of chemical elements formed annually), the entry of the bulk of litter into the soil, the active participation in the decomposition of bacteria, actinomycetes, and invertebrates, for which the chemical composition is favorable litter and general bioclimatic conditions.

Mesofauna plays a major role in the formation of chernozems, and the role of earthworms is especially important. Their number in the profile reaches 100 or more per 1 m2. With such numbers, earthworms annually throw up to 200 tons of soil per 1 hectare to the surface and, as a result of daily and seasonal migrations, make a large number of moves. Together with dead parts of plants, earthworms capture soil particles and, during the digestion process, form strong clay-humus complexes, which are released in the form of coprolites. According to G.N. Vysotsky, chernozems largely owe their granular structure to earthworms.

The virgin steppe was the habitat of a large number of vertebrates. The largest numbers and importance were the diggers (gophers, mole rats, voles and marmots), which mixed and threw large amounts of earth to the surface. By making burrows in the soil, they formed molehills - passages covered with a mass of the upper humus layer. Thanks to soil mixing, rodents gradually enriched humus horizons with carbonates, which slowed down the leaching processes, and deep horizons with humus, which led to a lowering of the humus horizon boundary. Thus, their activities contributed to the formation of the most characteristic properties of chernozems.

Currently, there are practically no virgin black soils left. Most of them are plowed. The biological factor of soil formation has changed significantly with the involvement of chernozems in agriculture. Agricultural vegetation covers the soil for no more than 4 months a year, with the exception of sowing perennial grasses. The biological cycle has become open. The amount of annually created phytomass in agrocenoses is less than in the virgin steppe; the difference in the amount of underground biomass produced is especially large. Less nitrogen and mineral elements are involved in the biological cycle.

On arable land, the number of microflora increases significantly, but at the same time the number and especially the biomass of invertebrates, primarily earthworms, sharply decreases. Vertebrate shrews do not live in arable land.

Chernozem soils develop under steppe forb-steppe herbaceous vegetation. The entire appearance of these soils indicates their richness in organic matter. In the profile of chernozems, a thick dark-colored humus, or humus-accumulative, layer (35-150 cm) is distinguished, containing a large amount of humus (250-700 t/ha).

The humus layer, due to the unequal intensity of its coloring with organic matter, is divided into 2 independent horizons: the upper most humus part is distinguished as the humus horizon A and the lower and lower to the humus streaks - as the transition horizon B 1. The transition to horizon B 1 is gradual and is characterized by the appearance of a brown tint in color, which noticeably intensifies downwards. The horizon of humus streaks B 2 stands out as an independent horizon. Below the humus layer, often covering the horizon of humus streaks, lies the horizon of maximum accumulation of carbonates - the carbonate, or carbonate-illuvial, horizon B k, gradually turning into rock C.

In virgin soils under virgin steppe vegetation in chernozem soils, a horizon of steppe felt A 0 is distinguished, consisting of the remains of herbaceous vegetation. On arable soils, the plowed part of horizon A is separated into an independent arable horizon A p.

A characteristic feature of chernozem soils is the granular and cloddy structure of the humus layer, especially clearly expressed in the subarable part of the A horizon.

Thanks to a thick humus layer with a water-resistant granular-lumpy structure, chernozems are characterized as soils of high natural fertility, with a significant supply of nutrients, favorable water-air and physicochemical properties.

The black earth zone has long been the most important area for the production of commercial grain in Russia. The vast expanses of black soil steppes have always attracted the attention of researchers.

V.V. Dokuchaev, who identified chernozem as a soil type, considered it as a soil of plant-terrestrial origin, formed when parent rocks changed under the influence of climate and steppe vegetation.

For the first time, the hypothesis about the plant-terrestrial origin of chernozem was formulated by M.V. Lomonosov in his treatise “On the Layers of the Earth” (1763).

The second in time of origin can be considered the marine hypothesis of the origin of chernozem, expressed by academician P.S. Pallas (1773) in relation to the chernozems of the Stavropol region, which, in his opinion, were formed from sea silt, rotting masses of reeds and other vegetation during the retreat of the sea.

The third theory is the idea of ​​the swamp genesis of chernozems. Here we need to consider two options. Geologist F.F. Wangenheim von Qualen (1853) suggested that chernozems were formed from crushed material from peat bogs and plant remains brought by a glacial flow from north to south and mixed with mineral silt. Much later, Academician V.R. returned to this point of view. Williams, who believed that chernozems were formed when peat bogs dried out and fluttered. From the standpoint of modern soil science, this version of the bog hypothesis, which linked the formation of chernozems with the supply of peat from the outside, is untenable.

Another approach turned out to be more fruitful. Academicians E.I. Eichwald (1850) and D.N. Borisyak (1852) suggested that chernozems arose from swamps during the gradual drying of the latter. The idea of ​​the swamp genesis of chernozems can be considered as the first step towards creating a much broader and deeper hypothesis of the paleohydromorphic past of chernozems, which was formulated in its most complete form by V.A. Kovdoy (1933, 1966, 1974).

Chernozems are relatively young soils; they were formed in the post-glacial period over the last 10-12 thousand years. This age was confirmed using radiocarbon dating, which made it possible to establish that the age of humus in the upper soil horizons is on average at least 1 thousand years, and the age of deep horizons is at least 7-8 thousand years (A.P. Vinogradov, 1969) .

The first classification of chernozems was given by V.V. Dokuchaev, who identified them as an independent type and divided them according to topographic conditions into mountain chernozems of watersheds, chernozems of slopes and valley chernozems of river terraces. In addition, V.V. Dokuchaev divided all chernozems according to humus content into four groups (4-7; 7-10; 10-13; 13-16%).

N.M. paid considerable attention to the classification of chernozems. Sibirtsev. In his classification (1901), the chernozem soil type was divided into subtypes - northern, fat, ordinary, southern.

Subsequently, the subtype of northern chernozems began to be called, according to S.I. Korzhinsky, degraded, and then it was divided into two independent subtypes - podzolized and leached chernozems.

In 1905 L.I. Prasolov, based on a study of the chernozems of the Azov and Ciscaucasia regions, identified a subtype of the Azov chernozems, which was later called Pre-Caucasian. The accumulation of information on chernozems in these regions made it possible to further consider their genetic characteristics as a result of provincial and facial conditions of soil formation and not to distinguish them at the level of an independent subtype.

Based on a synthesis of extensive materials on the study of chernozems in various regions of the country, the following division of chernozem soil type into subtypes and genera is currently accepted.

Below is a description of the main genera of chernozems.

Regular – distinguished in all subtypes; signs and properties correspond to the main characteristics of the subtype. In the full name of chernozem, the term of this genus is omitted.

Poorly differentiated - developed on sandy loam rocks, typical features of chernozems are poorly expressed (color, structure, etc.)

Deep-boiling - boil more deeply than the “ordinary chernozem” type, due to a more pronounced leaching regime due to the lighter mechanical composition or relief conditions. Stand out among the typical ones. Ordinary and southern chernozems.

Non-carbonate - developed on rocks poor in calcium silicate, there is no boiling and release of carbonates; found predominantly among typical, leached and podzolized subtypes of chernozems.

Solonetzic - within the humus layer they have a compacted solonetzic horizon with an exchangeable Na content of more than 5% of the capacity; stand out among ordinary and southern chernozems.

Solodized - characterized by the presence of a whitish powder in the humus layer, the flow of humus color, varnishing and grease along the edges of the structure in the lower horizons, and sometimes the presence of exchangeable sodium; distributed among typical, ordinary and southern chernozems.

Deep-gley - developed on two-membered and layered rocks, as well as in conditions of long-term preservation of winter permafrost.

Merged - developed on silty-clayey rocks in warm facies, characterized by a high density of horizon B. They stand out among the chernozems of the forest-steppe.

Underdeveloped - have an underdeveloped profile due to their youth or formation on highly skeletal or cartilaginous-gravelly rocks.

All chernozems are divided into types according to the following characteristics:

According to the thickness of the humus layer - super-thick (more than 120 cm), powerful (120-80 cm), medium-thick (80-40 cm), thin (40-25 cm) and very thin (less than 25 cm);

In addition, chernozems are divided into types according to the degree of severity of the accompanying process (weakly, moderately, strongly leached, weakly, moderately, strongly solonetzic, etc.).

A clear zonal pattern is observed in the geographic distribution of chernozem subtypes. Therefore, the zone of chernozem soils from north to south is divided into the following subzones: podzolized and leached chernozems, typical chernozems, ordinary chernozems and southern chernozems. The most clearly defined subzones are expressed in the European part of the country.

Chernozem soils in the forest-steppe zone are represented by podzolized, leached, and typical chernozems.

Podzolized chernozems. In the humus layer there are residual signs of the influence of the podzolic process in the form of a whitish powder - the main distinguishing morphological feature of this subtype. The humus profile of podzolized chernozems is gray, less often dark gray in color in horizon A and noticeably lighter in horizon B. Whitish powder, when present in abundance, gives the chernozem profile a grayish-ashy tint. Usually, in the form of a whitish coating, it seems to powder the structural units in the B1 horizon, but with strong podzolization, a whitish tint also occurs in the A horizon.

Carbonates lie significantly below the boundary of the humus layer (usually at a depth of 1.3-1.5 m). Therefore, in podzolized chernozems under the humus layer there is a brownish or reddish-brown illuvial horizon leached from carbonates with a nutty or prismatic structure with a distinct varnish, humus coatings and a whitish powder on the edges. Gradually, these signs weaken, and the horizon turns into rock containing carbonates at some depth in the form of calcareous tubes and cranes. They are divided into genera - ordinary, poorly differentiated, fused, non-carbonate.

When classifying podzolized chernozems into types, in addition to dividing them by thickness and humus content, they are divided according to the degree of podzolization into slightly podzolized and medium podzolized.

Chernozems are leached. Unlike podzolized chernozems, they do not have siliceous powder in the humus layer.

Horizon A is dark gray or black in color, with a clearly defined granular or granular-lumpy structure, with a loose build. Its thickness ranges from 30-35 to 40-50 cm. The lower boundary of horizon B 1 lies on average at a depth of 70-80 cm, but sometimes it can go lower. A characteristic morphological feature of leached chernozems is the presence under the B 1 horizon of a B 2 horizon leached from carbonates. This horizon has a clearly defined brownish color, humus streaks and residues, and a nutty-prismatic or prismatic structure. The transition to the next horizon - BC or C - is usually distinct, and the boundary is distinguished by the accumulation of carbonates in the form of lime mold and veins.

The main genera are ordinary, poorly differentiated, non-carbonate, deep-gley, fused.

Typical chernozems. They usually have a deep humus profile (90-120 cm or even more) and contain carbonates in the humus layer in the form of mycelium or calcareous tubes. Carbonates appear more often from a depth of 60-70 cm. For a more detailed morphological description of the humus layer, two horizons transitional in humus color are distinguished below horizon A - AB 1 and B 1.

Horizon AB 1 is dark gray with a faint, brownish tint downwards, and horizon B 1 is already distinguished by a distinct brown tint. In the lower part of the AB 1 horizon, or most often in the B 1 horizon, carbonate efflorescences are visible.

Horizon B 2 (BC) and the rock contain carbonates in the form of mycelium, calcareous tubes and cranes.

They are divided into the following genera: Ordinary, non-carbonate, deep-boiling, carbonate-salted.

Chernozems of the steppe zone

Chernozems in the steppe zone are represented by ordinary and southern chernozems.

Ordinary chernozems. Horizon A is dark gray or black, with a distinct granular or lumpy-granular structure, 30-40 cm thick. It gradually turns into horizon B 1 - dark gray with a clear brownish tint, with a lumpy or lumpy-prismatic structure. Most often, the thickness of the humus layer in ordinary chernozems is 65-80 cm.

Below horizon B 1 lies the horizon of humus streaks B 2, which often coincides with the carbonate illuvial horizon or very quickly transforms into it. The carbonates here are in white-eye form. This feature distinguishes ordinary chernozems from the previously considered subtypes.

The subtype of ordinary chernozems is divided into genera: ordinary, carbonate, solonetzic, deep-boiling, poorly differentiated and solodized.

Southern chernozems occupy the southern part of the steppe zone and directly border on dark chestnut soils.

Horizon A, 25-40 cm thick, has a dark gray or dark brown color, often with a slight brown tint, and a lumpy structure. Horizon B 1 is characterized by a clear brownish-brown color and a lumpy-prismatic structure. The total thickness of the humus layer (A+B 1) is 45-60 cm.

In the illuvial carbonate horizon, white-eye is usually clearly expressed. The boiling line is located in the lower part of horizon B 1 or at the boundary of the humus layer.

Southern chernozems are divided into the following genera: ordinary, solonetzic, carbonate, deep-boiling, poorly differentiated and solodized.

Chernozem soils are very diverse in mechanical composition, which is determined by the composition of soil-forming rocks.

A general feature of chernozem type soils is the absence of noticeable changes in mechanical composition during the process of soil formation. Only in podzolized chernozems and partially in leached ones is there a slight increase in the clay fraction down the profile. Some depletion of silt in the upper part of the profile is also observed in solonetzic and solodized chernozems.

The mineralogical composition of chernozems is dominated by primary minerals. Of the secondary minerals, most chernozem soils contain minerals of the montmorillonite and hydromica groups, in which montmorillonite dominates.

The silty fraction of chernozems also contains crystallized sesquioxides, amorphous substances and a small amount of highly dispersed quartz.

Highly dispersed minerals are distributed evenly along the profile. The difference in the mineralogical composition of chernozems is associated with the characteristics of the rocks and the weathering conditions of primary minerals.

Chemical composition.

Its most important features are the richness of chernozems in humus and the biogenic accumulation of plant nutrition elements in the humus profile. The relative homogeneity of the gross composition of the mineral part along the profile, the illuvial nature of the distribution of carbonates and the leaching of soils from easily soluble salts.

In the distribution of humus, there is a gradual decrease in its content with depth, which emphasizes the close connection of humus formation with the distribution of root systems of herbaceous vegetation. Chernozem humus is slightly soluble in water.

In accordance with the humus content, the amount of nitrogen also fluctuates (0.2-0.5%). The gross content of silicic acid and sesquioxides is uniform across the profile, which indicates the absence of processes of destruction of soil minerals. A slight depletion of R 2 O 3 and enrichment in silicic acid in the upper part of the profile are observed in podzolized and, to a lesser extent, leached chernozems, as well as in solonetzic and solodized ordinary and southern chernozems, which is associated with the peculiarities of their genesis.

The illuvial nature of the distribution of calcium carbonates in chernozems is due to the peculiarities of their water and thermal regimes, the dynamics of CO 2 in the soil air and soil solution. In spring, during the period of greatest development of downward currents, carbonates are washed out. However, if it does not reach the depth of maximum wetting, as is noted for easily soluble salts, but is delayed due to the very low solubility of calcium carbonates and low concentrations of carbon dioxide in the soil air and soil solution, since at this time active biological processes are not yet occurring in the soil. A subsequent increase in temperature activates the respiration of roots and activates the activity of microorganisms, which leads to an increase in the concentration of CO 2 in the soil solution and, as a consequence, to a greater formation of calcium bicarbonate, which begins to rise up the profile with ascending currents. Due to the increase in temperature as solutions move up the profile and carbon dioxide is removed, bicarbonate turns into carbonate and falls out of solution. The precipitation of carbonates as they rise with ascending currents is also associated with the consumption of water for evaporation and consumption by plants.

This is how the seasonal fluctuation of the upper limit of carbonate distribution, characteristic of chernozems, develops: it drops in spring and autumn and drops in summer. The scale of these fluctuations depends on the zonal and facial conditions of soil formation, as well as on the mechanical composition of the soil.

The richness of chernozems in humus and the intensive migration of biogenic calcium determine their favorable physicochemical properties: chernozems are characterized by high absorption capacity, saturation of the absorbing complex with bases, a close to neutral reaction of the upper horizons and high buffering capacity. In the composition of exchangeable cations, the main role belongs to calcium. Magnesium makes up 15-20% of the amount. In podzolized and leached chernozems, hydrogen is present in the absorption complex and hydrolytic acidity can reach a noticeable value. In ordinary and southern chernozems, the absorbed cations contain a small amount of Na+ and the proportion of Mg2+ slightly increases compared to other subtypes of chernozems. In solonetzic chernozems there is a large amount of absorbed sodium ion. Horizons containing free carbonates have a slightly alkaline reaction.

The physical properties of chernozem soils are largely determined by their high humus content, the thickness of humus horizons and good structuring. Therefore, chernozems are characterized by favorable physical properties: loose composition in the humus layer, high moisture capacity and good moisture permeability.

The best structured soils are leached, typical and ordinary heavy loamy and clayey chernozems. Podzolized and southern chernozems are characterized by a reduced content of water-stable aggregates. With the plowing of chernozems and their long-term agricultural use, the number of water-stable aggregates in the arable horizon decreases, but in typical and ordinary chernozems it remains at a fairly high level.

Due to their good structure, the density of chernozems in humus horizons is low and ranges from 1-1.22 g/cm 3 and only in sub-humus horizons it increases to 1.4-1.5 g/cm 3 . Density can increase noticeably in leached illuvial horizons of ordinary and southern chernozems. Solonetz chernozems are characterized by increased density in the B1 horizon.

The density of the solid phase in chernozems in the upper horizons is low (2.4-2.5 g/cm3), which is due to the richness of the upper parts of the profile in humus. In subhumus horizons and in rock, its value increases to 2.55-2.65. The good structure of chernozems determines their high porosity in humus horizons (50-60%), which gradually decreases with depth. Chernozem soils are characterized by favorable content of capillary and non-capillary porosity.

Non-capillary porosity can be 1/3 of the total porosity, which ensures good air and water permeability of chernozems.

The highest water permeability is in the arable horizons A and the upper part of the horizon B1, where the water-resistant lumpy and granular structure is well expressed. The arable part of horizon A absorbs moisture 1.5-2.5 times slower than the subarable part, which is due to the spraying of the structure and compaction of the horizon. Deep cultivation of chernozem soils and maintaining their surface in a loose state contributes to the best absorption of precipitation. A thick humus layer determines the high moisture capacity of chernozems.

The black earth zone is the most important agricultural region of the country. Grains, industrial and oilseeds are grown here: winter and spring wheat, corn, sunflowers, sugar beets, curly flax and many others. These are areas of widely developed livestock farming and fruit growing.

The most important task of agricultural production on chernozem soils is the correct use of their high potential fertility and the protection of the humus layer from destruction. The main ways to solve this problem are rational methods of processing, accumulation and proper use of moisture, applying fertilizers, improving the structure of sown areas, introducing high-yielding crops and varieties, and combating erosion.

Within each subtype of chernozem soils, their agronomic assessment is determined by the following genetic characteristics: the thickness of humus horizons and the total reserve of humus, mechanical composition, degree of erosion, properties and thickness of soil-forming rocks, as well as the level of soil cultivation. The greater the thickness of the humus horizon, the richer the chernozems in general reserves of nutrients. On chernozems with a large thickness of humus horizons, the water regime develops more favorably. Therefore, in chernozems there is a direct correlation between the yield of agricultural crops and the thickness of the humus layer and humus reserves.

The processes of planar erosion, causing the washout of the upper most fertile layer, sharply reduce the fertility of chernozems, worsening their water, nutritional and microbiological regimes and physico-chemical and physicomechanical properties.

The agronomic advantages of chernozems developed on the eluvium of shale, limestone and other rocks underlain by sandstones and other dense rocks are decreasing.

Within individual subtypes, the agronomic assessment of chernozems is also influenced by their subtype and generic characteristics. Thus, for leached chernozems, these differences are associated with the degree of leaching of their profile.

Drained chernozems are characterized by poor agrophysical properties. In the subzones of ordinary and southern chernozems, the agronomic properties of carbonate and solonetzic chernozems are deteriorating. Carbonate chernozems are susceptible to wind erosion; phosphorus fertilizers applied to them quickly transform into forms that are difficult for plants to reach.

Alone chernozems have unfavorable input-physical and input-mechanical properties, and therefore the higher the degree of solonetsity, the worse the agronomic properties of chernozems and the lower the yield of agricultural crops. The relative increase in the participation of solonetzes in complexes with chernozems worsens the assessment of the land mass.

To increase the fertility of chernozem soils, the accumulation of moisture and its rational use are very important, especially in the subzones of ordinary and southern chernozems. Therefore, the first place among agrotechnical practices should be given to measures that ensure short deadlines for spring field work and the creation of the best water regime.

Such measures include: the introduction of clean fallows, early deep plowing, rolling and timely harrowing of the soil, cultivation across slopes, autumn furrowing and slicing of fields to absorb melt water and prevent erosion.

The most difficult problem is the irrigation of black soils. It is most effective on medium and light soils that are not prone to compaction, in areas with good natural drainage. In this case, irrigation should be additional to natural moisture to maintain soil moisture at least 70-75% of the PPV during the growing season.

Irrigation should be carried out with water with a total salt concentration of less than 1 g/l and low-intensity sprinkling.

With excessive watering, the use of mineralized water, as well as in areas with poor drainage and heavy soils, negative phenomena develop that lead to the deterioration of chernozems - waterlogging, secondary salinization, alkalinization, coalescence, etc.

Of exceptional importance, especially for ordinary and southern chernozems, is snow retention (sowing curtains, protective strips, etc.).

On light chernozem soils subject to wind erosion, good results are achieved by moldless and flat autumn tillage, in which the remaining stubble contributes to the accumulation of snow and protects the soil from blowing away.

Particular attention in the complex of agrotechnical measures for the accumulation of moisture among ordinary and southern chernozems requires solonetzic and carbonate soils, which have unfavorable agrophysical properties and have reduced water yield.

Chernozem soils, despite their high potential fertility, respond well to fertilizers, especially forest-steppe chernozems, since moisture conditions are most favorable here. On ordinary and southern chernozems, the maximum effect of fertilizers is achieved when moistening measures are carried out.

The positive effect of nitrogen fertilizers increases from clayey and heavy loamy soils to light loamy and sandy loam soils. This is explained by the more pronounced nitrification ability of chernozem soils of heavy mechanical composition due to their great richness in humus and better aggregation.

In chernozems, sedentary forms of phosphates predominate, so these soils respond well to phosphate fertilizers. Phosphate rock is effective on podzolized and leached chernozems with high hydrolytic acidity.

Manure has a significant positive effect on all chernozem soils, but especially on chernozems of light texture. First of all, it is applied to grains, sugar beets and potatoes.

The effectiveness of manure decreases from forest-steppe chernozems to southern chernozems due to worsening moisture conditions. Therefore, in areas with a pronounced moisture deficit, the use of well-decomposed manure, its deep incorporation and moisturizing measures are of great importance.

Mobilization and rational use of the potential fertility of chernozem soils requires the activation of microbiological processes using the correct processing techniques in combination with measures to improve the water regime.

The systematic use of physiologically acidic fertilizers and the constant removal of calcium from agricultural crops leads to calcium deficiency and acidification of chernozem soils. Available data indicate a positive effect of liming on plant yield and its quality.

Protective forest belts play a major role in the chernozem zone - a comprehensive means of improving the microclimate, water regime, and for a number of areas, as a means of combating erosion.

When carrying out work on protective forest planting, it is necessary to take into account the characteristics of the forest-vegetative properties of various chernozem soils. Forest-steppe chernozems are podzolized, leached and typical, suitable for planting oak and other forest crops without special reclamation measures.

Ordinary and southern chernozems require agrotechnical measures for snow accumulation, absorption of melt water and proper moisture consumption, and also allow a more limited range of crops. For solonetzous ordinary and southern chernozems, as well as solodized chernozems, in addition to high agricultural technology and moisturizing measures, special types of forest crops are necessary.

The soil-vegetation cover and fauna of the Russian Plain show a clearly defined zonation. Here there is a change in natural zones from tundra to deserts. Each zone is characterized by certain types of soil, peculiar vegetation and associated fauna.

Soils. In the northern part of the plain, within the tundra zone, tundra coarse humus gley soils are most common, in the upper horizon of which there is an accumulation of weakly decomposed mosses and strong gleying. The degree of gleying decreases with depth. In well-drained areas, tundra gleyic soils with a lower degree of gleyization are found. Where precipitation flow is difficult, tundra peat and peat gley soils are formed.

Under the forests of the Russian Plain, soils of the podzolic type are common. In the north, these are gley-podzolic soils combined with bog-podzolic peat and peaty-gley soils; in the middle taiga there are typical podzolic soils of varying degrees of podzolization, and to the south there are soddy-podzolic soils, developed not only in the southern taiga, but also in the zone of mixed and deciduous forests. Under broad-leaved, predominantly oak forests, i.e., mainly in the forest-steppe zone, gray forest soils are formed.

Chernozems are common under the steppe vegetation. In more humid conditions, leached and podzolized chernozems are developed, which, as dryness increases, are replaced by typical, ordinary and southern chernozems. In the southeast of the plain there are chestnut and brown desert-steppe soils. It was here that they became most widespread in Russia. Chestnut, light chestnut and brown soils are often solonetzic. Among these soils in dry steppes, semi-deserts and deserts of the Caspian region, solonetzes and solonchaks are common.

The vegetation of the Russian Plain differs from the vegetation cover of other large regions of our country in a number of very significant features. Only here are mixed coniferous-deciduous and broad-leaved forests, semi-deserts and deserts with their grass-wormwood, wormwood and wormwood-saltweed vegetation widespread. Only on the Russian Plain, spruce dominates in the sparse forests of the forest-tundra, and in the forest-steppe the main forest-forming species is oak. The taiga of the plain is distinguished by its amazing monotony: all subzones are dominated by spruce forests, which give way to pine forests on a sandy substrate. In the eastern part of the plain, the role of Siberian conifers in the taiga is increasing. The steppe here occupies the largest area in Russia, and the tundra is a relatively small area and is represented mainly by southern shrub tundras of dwarf birch and willows.

In the fauna of the East European Plain there are western and eastern species of animals. Tundra, forest, steppe and, to a lesser extent, desert animals are common here. Forest animals are the most widely represented. Western species of animals gravitate towards mixed and broad-leaved forests (pine marten, black polecat, hazel and garden dormouse, etc.). The western border of the range of some eastern animal species (chipmunk, weasel weasel, Ob lemming, etc.) passes through the taiga and tundra of the Russian Plain. From the Asian steppes, the saiga antelope, which is now found only in the semi-deserts and deserts of the Caspian region, the marmot and the reddish ground squirrel penetrated the plain. Semi-deserts and deserts are inhabited by inhabitants of the Central Asian subregion of the Palaearctic (jerboas, gerbils, a number of snakes, etc.).

The following natural zones are clearly defined on the East European Plain: tundra and forest-tundra, taiga, zone of mixed and broad-leaved forests, forest-steppe, steppe, semi-desert and desert.

In general, the tundra and forest-tundra zones - humid, moderately cold - occupy the coast of the Barents Sea on the moraine-marine plain in the subarctic climate zone

European tundra and forest-tundra are warmer and wetter than Asian ones. Frequent winter cyclones originating on the Barents Sea branch of the Arctic front, associated with the trough of the Icelandic low, bring quite warm sea air from the Atlantic and the non-freezing part of the Barents Sea. This is reflected in the distribution of winter temperatures (the average January temperature on the Kanin Peninsula is -10°C, and on the Yugorsky Peninsula -20°C), annual precipitation (about 600 mm in the west of the tundra, and 500 mm in the east), and the highest perennial temperatures permafrost (from 0 to -3°C).

In the European tundra, only two subzones are expressed: typical, moss-lichen, and southern, or shrub. Typical tundra is especially widely represented in the area from the Timan Ridge to the Urals. The southern subzone is characterized by a predominance of shrub (dwarf birch and willow) and shrub communities in the vegetation cover in combination with moss, sphagnum and lichen-sphagnum bogs.

Along the southern edge of the tundra there is a transition zone of forest-tundra. The forests here are open woodlands consisting of Siberian spruce 5-8 m high, joined by birch and Sukachev larch. Low-lying areas are occupied by swamps or dense thickets of bushes - small willows and birch dwarf. Lots of crowberries, blueberries, blueberries, herbs, lichens. In the north of the forest-tundra, open spaces are common, which are characterized by single scattered oppressed crooked trees. Tall forests penetrate deep into the territory only along river valleys due to the warming influence of river waters and protection from strong winds. In the south of the forest-tundra, in open birch forests, bird cherry appears with the latest flowering on the plain (June 30) and mountain ash (blooms around July 5).

Mossy tundras contain large reserves of green fodder and serve as a valuable food source for reindeer husbandry.

The fauna of the tundra is monotonous and characterized by a poverty of forms. Typical mammals are the domestic reindeer and the polar wolf. Rodents are represented by pieds - the Ob lemming. The arctic fox is widespread everywhere. It enters the forest-tundra and even the northern taiga. Stoats and white hare are often found in river valleys. A common animal in the forest-tundra is the wolverine, but in the summer it goes into the tundra to the shores of the Barents Sea.

The taiga zone extends south of the forest-tundra. Its southern border runs along the line St. Petersburg - Novgorod - Yaroslavl - Nizhny Novgorod - Kazan. In the southwest, the taiga merges with the zone of mixed and broad-leaved forests, and in the southeast - with the forest-steppe zone.

The taiga of the Russian Plain differs from the Siberian one in its geographical location and history of development of the territory, and they determined the modern appearance of its nature. The European taiga receives more cages than the West Siberian taiga. Their annual quantity on the plains is more than 600 mm, and on the hills - up to 800 mm. The entire zone of excess moisture, since precipitation exceeds evaporation by 200 mm. There are many lakes in the Onega and Volga basins, and the eastern part of the taiga is poor in lakes, but rich in swamps.

Podzolic soils are developed on moraine and fluvioglacial deposits of the taiga. The flat topography of the northern part of the forest zone, as well as the water-resistant properties of the soils, contribute to severe swampiness and the development of bog-podzolic peaty and peaty-gley soils east of the Northern Dvina. Typical podzolic soils are characteristic of the middle part of the taiga. The podzol formation process is weakened in the north, where low temperatures and waterlogging prevent the formation of podzol, as well as in the south due to a decrease in moisture content.

The European taiga is characterized by dark coniferous spruce forests: only here are Norway spruce (common spruce) and Siberian spruce found together. Norway spruce moves east only to the Urals, while Siberian spruce enters the Kola Peninsula and eastern Karelia. Siberian fir, Sukachev larch and Siberian cedar crossed the Urals to the west. There are many pine forests along the river valleys and outwash. A secondary role in forests belongs to deciduous trees: birch, aspen, alder. Lots of sphagnum bogs. Dry and floodplain meadows are widespread in the zone.

Among the animals typical for the taiga are reindeer, wolverine, lynx, wolf, squirrel, and white hare. The Siberian weasel and the Siberian rodent, the chipmunk, came to the northeast of the taiga and settled west to the Northern Dvina and the White Sea. Mink, otter, and water shrew live along the river banks. There are many birds in the taiga. Capercaillie and hazel grouse are found everywhere, and white partridge is found in moss swamps.

The European taiga is divided into three subzones: northern, middle and southern. The northern taiga is characterized by excessive moisture. In its western part the winters are snowy and moderately cold, and in the eastern part the winters are cold and quite snowy. The forests here are low-growing and sparse of spruce and pine (green moss, long moss, sphagnum and lichen).

The middle taiga is characterized by excessive moisture, moderately cold and cold, snowy winters. Here, blueberry spruce forests predominate (from European and Siberian spruce).

The southern taiga is also quite humid, but has significant differences in winter temperatures (the average January temperature in the west is -6°C, in the east -13°C), the depth of soil freezing in the west is 30 cm, in the east 60 cm or more.

Here the highest snow cover depth on the Russian Plain is observed - 70-90 cm. Summer is cool, with cloudy, often rainy weather. The average temperature in July is 14-16°C; annual precipitation is 600-800 mm, gradually increasing to the east, approaching the Urals. The rivers of the province are full of water. The large thickness of the snow cover determines their high floods, which occur in May. There are many lakes in the lowlands. They are often found among swamps.

The Pechora province lies in the northern taiga subzone, only its extreme south falls into the middle taiga. The vegetation cover is dominated by sparse spruce and pine forests. Siberian conifers are common in the tree stand: cedar, fir, larch. Forests are usually swampy. Gleyic-podzolic soils develop under them. Only in the valley areas and on the slopes of the hills do non-marsh spruce forests grow. In the northern part, primary birch forests are quite widespread and are also largely swampy. There are a lot of swamps in the province. Hilly ones predominate, and in the southern part - sphagnum ridge-hollows. Floodplain meadows with high grass stand are developed along the rivers. The taiga is home to European and Siberian animal species.

The province is rich in oil and gas deposits. The population of the taiga is engaged in fur farming.

The zone of mixed and deciduous forests is located in the western part of the plain between the taiga and forest-steppe and extends from the western borders of Russia to the confluence of the Oka and the Volga. The territory of the zone is open to the Atlantic Ocean and its impact on the climate is decisive.

The zone is characterized by a mild, moderately warm climate. The relief exhibits a combination of hills (200 m or more) and lowlands. The strata plains are overlain by moraine, lacustrine-alluvial, fluvioglacial and loess rocks. Within the zone, under conditions of a moderately humid and moderately warm Atlantic-continental climate, soddy-podzolic and gray forest soils will form.

The climate of the zone is favorable for the growth of coniferous tree species along with broad-leaved trees. Depending on the relief conditions and the degree of moisture, meadows and swamps are also formed. European coniferous-deciduous forests are heterogeneous. Among the broad-leaved species in the zone, linden, ash, elm, and oak are common. As you move east, due to the increasing continentality of the climate, the southern border of the zone shifts significantly to the north, the role of spruce and fir increases, while the role of broad-leaved species decreases. The most widespread of the broad-leaved species in the zone is linden, which forms the second tier in mixed forests.

Typical animals of the zone are wild boar, elk, bison, black or forest polecat, badger, etc. In recent decades, the number of wild boar, river beaver and elk has increased significantly.

The zone of coniferous-deciduous forests has long been densely populated and developed, so its nature has been greatly changed by human activity. For example, forests occupy only 30% of the zone's territory; the most convenient areas are plowed or used for pastures;

The forest-steppe zone, moderately humid and moderately warm, is located in the south of the Atlantic-continental climate region of the temperate zone of the East European Plain. Its southern border runs approximately south of Voronezh, Saratov, rises along the Volga valley to the north and runs along the Samara valley. The European forest-steppe is characterized by the main natural features of the entire zone, but at the same time it differs in its natural appearance from the forest-steppe of the West Siberian Plain, since it has differences in geographical location and the history of the formation of the territory. The forest-steppe extends from southwest to northeast, i.e. it occupies the southernmost position in the west of the plain. This determined its bioclimatic features: its western part, up to the Voronezh meridian, has a semi-humid climate and richer vegetation, while the eastern part is semi-arid with depleted vegetation cover.

Winter in the east is colder and snowier, the average temperature is -12°...-16°С. Summer in the European forest-steppe can be moderately warm with sufficient moisture. Then the vegetation and soils receive a lot of moisture, groundwater is replenished with a sufficient amount of moisture, its level rises and becomes accessible to plant roots in many places, and spring water outputs in ravines, gullies and river valleys increase. In such a summer, steppe, forest and cultivated vegetation develops luxuriantly (abundantly). Summer can be hot with droughts and dry winds. This type of weather has a detrimental effect on the development of natural and cultivated vegetation. An important bioclimatic zero band of the ratio of precipitation and evaporation passes through the forest-steppe zone: to the north of it there is 100-200 mm more precipitation than evaporation, and to the south there is 100-200 mm less evaporation.

The East European forest-steppe formed on highlands and lowlands in the regional region of the Dnieper glaciation, covered with loess-like loams. The relief is characterized by erosional dissection, which creates a certain diversity of soil cover. The soils of watershed elevated areas under oak groves are characterized by significant podzolization. Along high river terraces with loess-like covers, tongues of degraded and leached chernozems extend to the north. The most typical for the northern part of the zone are gray forest soils, slightly podzolized, developed on loess-like loams. Leached and podzolized chernozems are typical for the southern strip of forest-steppe. Gray forest soils are developed in small areas along watersheds. Of the intrazonal soils, common in depressions - steppe saucers, malt is characteristic.

The natural vegetation of the forest-steppe has hardly been preserved. The forests here are found in small islands. The forest-steppe of the Russian Plain is oak, which distinguishes it from the more eastern regions of Russia.

Steppe areas in the forest-steppe, once covered primarily with forbs (V.V. Alekhin called them northern colorful forbs), have been plowed. Small patches of virgin steppes remain along ravines and incremental slopes that are inconvenient for plowing, as well as in nature reserves.

The fauna of the zone consists of inhabitants of forests and steppes. There are no species of our own here. Due to the intense plowing of the zone, the animal world is now dominated by animals of open spaces and human companions.

Semi-desert and desert zones within Russia are located in the southwestern part of the Caspian Lowland and on the Turan Plain. They adjoin the coast of the Caspian Sea, adjacent to the semi-deserts and deserts of Kazakhstan in the east and Eastern Ciscaucasia in the southwest.

The climate of semi-deserts and deserts is moderately dry and very warm with an annual precipitation of 300-400 mm. Evaporation exceeds precipitation by 400-700 mm. Winters are quite cold, with negative temperatures prevailing. The average January temperature in the southwest is 7°C, and in the northeast it is 1°C. In winter, a snow cover is formed, the height of which reaches 10-15 cm. The snow lies for 60-80 days. In the extreme south of the Caspian lowland, stable snow cover does not form every year. It usually forms 15-30 days after the average daily temperature passes through 0°C. This contributes to seasonal freezing of the soil to a depth of 80 cm (about the same amount as in the middle taiga).

Semi-desert and desert are characterized by an abundance of salt lakes, salt marshes and solonetzes. Therefore, light chestnut solonetzic soils are developed there, the absorption complex of which contains sodium. The thickness of humus horizons is 30-40 cm, and the humus content is only 1.3%. In the north of the semi-desert zone, vegetation of the wormwood-grass type is developed with the dominance of feather grass (tyrsa) and Lessing, as well as Tauric wormwood and Lerch. To the south, the number of cereals decreases, wormwood begins to predominate and the number of saltworts increases. The low-growing grass cover consists of white and black wormwood, fescue, thin-legged grass, xerophytic feather grass, and isen shrub (Kochia prostrata). In spring, tulips, buttercups, and rhubarb appear. White wormwood grows on slightly saline loams. Clayey, more saline soils are covered with black wormwood. On the salt licks, in addition to black wormwood, biyurgun and kermek saltworts and tamarix shrubs grow.

For the fauna of semi-deserts and deserts, ground squirrels and many jerboas are common, of which the small one, the ground hare, and the woolly-footed hare are typical. There are numerous gerbils - combed, southern, or midday, inhabiting mainly sands. The common species are ermine, weasel, steppe ferret, badger, wolf, common fox and small corsac fox, and many reptiles.

URAL

The Ural mountainous country stretches from north to south for more than 2000 km from 69°30" N to 50° 12" N. It crosses five natural zones of Northern Eurasia - tundra, forest-tundra, taiga, forest-steppe and steppe. The width of the mountain belt is less than 50 km in the north, and over 150 km in the south. Together with the foothill plains that are part of the country, its width varies from 50-60 km in the northern part of the region to 400 km in the southern part.

The Urals have long been considered the border between two parts of the world - Europe and Asia. The border is drawn along the axial part of the mountains, and in the southeast along the Ural River.

For centuries, the Russian Plain served as a territory connecting Western and Eastern civilizations along trade routes. Historically, two busy trade arteries ran through these lands. The first is known as the “path from the Varangians to the Greeks.” According to it, as is known from school history, medieval trade in goods of the peoples of the East and Rus' with the states of Western Europe was carried out.

The second is the route along the Volga, which made it possible to transport goods by ship to Southern Europe from China, India and Central Asia and in the opposite direction. The first Russian cities were built along trade routes - Kyiv, Smolensk, Rostov. Veliky Novgorod became the northern gateway from the “Varangians”, protecting the security of trade.

Now the Russian Plain is still a territory of strategic importance. The capital of the country and the largest cities are located on its lands. The most important administrative centers for the life of the state are concentrated here.

Geographical position of the plain

The East European Plain, or Russian, occupies territories in eastern Europe. In Russia, these are its extreme western lands. In the northwest and west it is limited by the Scandinavian Mountains, the Barents and White Seas, the Baltic coast and the Vistula River. In the east and southeast it neighbors the Ural Mountains and the Caucasus. In the south, the plain is limited by the shores of the Black, Azov and Caspian seas.

Relief features and landscape

The East European Plain is represented by a gently sloping relief, formed as a result of faults in tectonic rocks. Based on relief features, the massif can be divided into three stripes: central, southern and northern. The center of the plain consists of alternating vast hills and lowlands. The north and south are mostly represented by lowlands with rare low altitudes.

Although the relief is formed in a tectonic manner and minor tremors are possible in the area, there are no noticeable earthquakes here.

Natural areas and regions

(The plain has planes with characteristic smooth drops)

The East European Plain includes all natural zones found in Russia:

• Tundra and forest-tundra are represented by the nature of the north of the Kola Peninsula and occupy a small part of the territory, slightly expanding to the east. The vegetation of the tundra, namely shrubs, mosses and lichens, is replaced by birch forests of the forest-tundra.
• Taiga, with its pine and spruce forests, occupies the north and center of the plain. On the borders with mixed broad-leaved forests, areas are often swampy. A typical Eastern European landscape - coniferous and mixed forests and swamps give way to small rivers and lakes.
• In the forest-steppe zone you can see alternating hills and lowlands. Oak and ash forests are typical for this zone. You can often find birch and aspen forests.
• The steppe is represented by valleys, where oak forests and groves, forests of alder and elm grow near the river banks, and tulips and sages bloom in the fields.
• In the Caspian lowland there are semi-deserts and deserts, where the climate is harsh and the soil is saline, but even there you can find vegetation in the form of various varieties of cacti, wormwood and plants that adapt well to sudden changes in daily temperatures.

Rivers and lakes of the plain

(River on a flat area of ​​the Ryazan region)

The rivers of the “Russian Valley” are majestic and slowly flow their waters in one of two directions - north or south, to the Arctic and Atlantic oceans, or to the southern inland seas of the continent. Northern rivers flow into the Barents, White or Baltic seas. Rivers in the southern direction - into the Black, Azov or Caspian Seas. The largest river in Europe, the Volga, also “flows lazily” through the lands of the East European Plain.

The Russian Plain is the kingdom of natural water in all its manifestations. A glacier that passed through the plain thousands of years ago formed many lakes on its territory. There are especially many of them in Karelia. The consequences of the presence of the glacier were the emergence in the North-West of such large lakes as Ladoga, Onega, and the Pskov-Peipus reservoir.

Under the thickness of the earth in the localization of the Russian Plain, reserves of artesian water are stored in the amount of three underground pools of huge volumes and many located at shallower depths.

Climate of the East European Plain

(Flat terrain with slight drops near Pskov)

The Atlantic dictates the weather regime on the Russian Plain. Western winds, air masses that move moisture, make summers on the plain warm and humid, winters cold and windy. During the cold season, winds from the Atlantic bring about ten cyclones, contributing to variable heat and cold. But air masses from the Arctic Ocean also tend to the plain.

Therefore, the climate becomes continental only in the interior of the massif, closer to the south and southeast. The East European Plain has two climatic zones - subarctic and temperate, increasing continentality to the east.

To better understand the environmental problems of the Russian Plain, it is necessary to consider in detail what natural resources this geographic area has and what makes it remarkable.

Features of the Russian Plain

First of all, we will answer the question of where the Russian Plain is located. The East European Plain is located on the Eurasian continent and ranks second in area in the world after the Amazon Plain. The second name of the East European Plain is Russian. This is due to the fact that a significant part of it is occupied by the state of Russia. It is in this territory that most of the country's population is concentrated and the largest cities are located.

The length of the plain from north to south is almost 2.5 thousand km, and from east to west - about 3 thousand km. Almost the entire territory of the Russian Plain has a flat topography with a slight slope - no more than 5 degrees. This is mainly due to the fact that the plain almost completely coincides with the East European Platform. Destructive natural phenomena (earthquakes) are not felt here and, as a result, there are no destructive natural phenomena.

The average height of the plain is about 200 m above sea level. It reaches its maximum height on the Bugulma-Belebeevskaya Upland - 479 m. The Russian Plain can be conditionally divided into three stripes: northern, central and southern. On its territory there are a number of hills: the Central Russian Plain, the Smolensk-Moscow Upland - and lowlands: the Polesie, Oka-Don Plain, etc.

The Russian Plain is rich in resources. There are all types of minerals here: ore, non-metallic, combustible. A special place is occupied by the extraction of iron ore, oil and gas.

1. Ore

Kursk iron ore Deposits: Lebedinskoye, Mikhailovskoye, Stoilenskoye, Yakovlevskoye. The ore of these developed deposits has a high iron content - 41.5%.

2. Nonmetallic

• Bauxite. Deposits: Vislovskoe. The alumina content in the rock reaches 70%.
• Chalk, marl, fine-grained sand. Deposits: Volskoye, Tashlinskoye, Dyatkovskoye, etc.
• Brown coal. Swimming pools: Donetsk, Podmoskovny, Pechora.
• Diamonds. Deposits of the Arkhangelsk region.

3. Flammable

• Oil and gas. Oil and gas bearing areas: Timan-Pechora and Volga-Ural.
• Oil shale. Deposits: Kashpirovskoye, Obseshyrtskoye.

Minerals of the Russian Plain are mined in various ways, which has a negative impact on the environment. Contamination of soil, water and atmosphere occurs.

The influence of human activity on the nature of the East European Plain

The environmental problems of the Russian Plain are largely related to human activity: the development of mineral deposits, the construction of cities, roads, emissions from large enterprises, their use of huge volumes of water, the reserves of which do not have time to be replenished, and are also polluted.

Below we will consider all of the Russian Plain. The table will show what problems exist and where they are located. Possible methods of struggle are presented.

Climate of the Russian Plain

The climate of the East European Plain is temperate continental. Continentality increases as you move inland. The average temperature of the plain in the coldest month (January) is -8 degrees in the west and -12 degrees in the east. In the warmest month (July), the average temperature in the northwest is +18 degrees, in the southeast +21 degrees.

The greatest amount of precipitation falls in the warm season - approximately 60-70% of the annual amount. There is more precipitation over the highlands than over the lowlands. The annual precipitation in the western part is 800 mm per year, in the eastern part - 600 mm.

On the Russian Plain there are several natural zones: steppes and semi-deserts, forest-steppes, taiga, tundra (when moving from south to north).

The forest resources of the plain are represented mainly by coniferous species - pine and spruce. Previously, forests were actively cut down and used in the wood processing industry. Currently, forests have recreational, water-regulating and water-protection significance.

Flora and fauna of the East European Plain

Due to small climatic differences, pronounced soil and plant zonation can be observed on the territory of the Russian Plain. Northern soddy-podzolic soils to the south are replaced by more fertile chernozems, which affects the nature of vegetation.

Flora and fauna have suffered significantly due to human activities. Many plant species have disappeared. Of the fauna, the greatest damage was caused to fur-bearing animals, which have always been a desirable object of hunting. The mink, muskrat, raccoon dog, and beaver are endangered. Such large ungulates as the tarpan have been exterminated forever, and the saiga and bison have almost disappeared.

To preserve certain species of animals and plants, nature reserves were created: Oksky, Galichya Gora, Central Chernozemny named after. V.V. Alekhina, Forest on Vorskla, etc.

Rivers and seas of the East European Plain

Where the Russian Plain is located, there are many rivers and lakes. The main rivers that play a major role in human economic activity are the Volga, Oka and Don.

The Volga is the largest river in Europe. The Volga-Kama hydro-industrial complex is located on it, which includes a dam, a hydroelectric power station and a reservoir. The length of the Volga is 3631 km. Many of its tributaries are used by the economy for irrigation.

Don also plays a significant role in industrial activities. Its length is 1870 km. The Volga-Don shipping canal and the Tsimlyansk reservoir are especially important.

In addition to these large rivers, the following flow on the plain: Khoper, Voronezh, Bityug, Northern Onega, Kem and others.

In addition to rivers, the Russian Plain includes the Barents, White, Black, and Caspian.

The Nord Stream gas pipeline runs along the bottom of the Baltic Sea. This affects the ecological situation of the hydrological object. During the construction of the gas pipeline, water became clogged and many species of fish decreased in number.

In the Baltic, Barents, and Caspian Seas, some minerals are extracted, which, in turn, has an adverse effect on the waters. Some industrial waste leaks into the seas.

In the Barents and Black Seas, several types of fish are caught on an industrial scale: cod, herring, flounder, haddock, halibut, catfish, anchovy, pike perch, mackerel, etc.

Fishing, mainly sturgeon, is carried out in the Caspian Sea. Due to favorable natural conditions, there are many sanatoriums and tourist centers on the seashore. There are shipping routes along the Black Sea. Petroleum products are exported from Russian ports.

Groundwater of the Russian Plain

In addition to surface water, people use underground water, which due to irrational use has an adverse effect on soils - subsidence is formed, etc. There are three large artesian basins on the plain: the Caspian, Central Russian and East Russian. They serve as a source of water supply for a vast area.