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Nature, plants and animals of the Astrakhan region. Geography of the Astrakhan region

in the discipline "Soil Science"

"Soils of the Astrakhan region"

Completed by student group: 321621

Name: Kabanov Roman Olegovich

Received: Korol V.V.

Tula 2013

Introduction

The surface of the Astrakhan region is mostly flat, partly below sea level (altitudes up to 150 m, Bolshoe Bogdo). On the Volga-Akhtuba floodplain - near-river manes, high sandy ridges, many channels, oxbow lakes. In the Volga delta, Baer hillocks are characteristic. The Astrakhan region is located in the zone of desert-steppe soils and is partly included in the subzone of brown semi-desert soils. A characteristic feature of the soil cover is its complexity, which manifests itself in a mosaic combination of brown soils with light chestnut soils, solonetzes and solonchaks. These are the most common soils in the Astrakhan region.

Soil systems are very complex, multicomponent formations with high spatial and temporal variability and no less complex relationships with other components of the biogeocenosis. Fully developed zonal soils perform the functions of a habitat for animals and microorganisms, a habitat for the growth and reproduction of plant associations, accumulate elements that determine its fertility, and regulate moisture circulation (water regime) in the soil-atmosphere and soil-groundwater systems. In addition, water-soluble salts migrate in the soil layer (Glazovskaya, 1976, 1988).

Within the Volga-Akhtuba floodplain, depending on the type of water regime and the vegetation cover and metabolic processes associated with it, groups of soddy saturated, meadow saturated and meadow-marsh soils, to some extent saline, were formed. The source of salinity is relict salinization of parent rocks and mineralized groundwater. As a result of the seasonal dynamics of the groundwater regime, the degree of soil salinization is not constant.

Natural conditions of soil formation in the Astrakhan region

The region occupies almost the middle position between the equator and the North Pole. The duration of the period with temperatures above 0°C is 235-260 days. An important role in climate formation is played by the position of the region relative to the World Ocean. The region is located in the temperate zone, which is characterized by the transfer of air masses from the Atlantic Ocean to the west. Often, air masses break into the territory from the Arctic Ocean, sometimes from the Black and Mediterranean Seas. But all these reservoirs are located quite far from our region. The influence of the Atlantic Ocean is associated with the arrival of cyclones, and, consequently, precipitation, a decrease in temperature in summer and an increase in winter. With the advent of the Siberian anticyclone, pressure rises in the region, cloudiness and the amount of precipitation decrease. Therefore, in winter, under conditions of short days and clear skies, low temperatures are set. In summer, this cyclone causes an increase in air temperature and leads to the establishment of hot days. The flatness of the relief to the north of the Astrakhan region contributes to the unimpeded passage of cold arctic masses, which are associated with a decrease in temperature at any time of the year.

The underlying surface is an important climate-forming factor. The main background of the region is a plain, sometimes with sandy massifs. The exception is the Volga-Akhtuba floodplain and the Volga delta with a large amount of water surface, meadow vegetation and ribbon forests. The climate here has its own specific features: throughout the year, the air temperature at night is higher than in the surrounding desert areas, and in summer it is 2-4 ° C cooler than outside this territory.

The climate of the Astrakhan region is temperate, sharply continental - with high temperatures in summer, low temperatures in winter, large annual and summer daily air temperature amplitudes, low precipitation and high evaporation. The average annual air temperature varies from south to north from 10°С to 8°С. The coldest month is January, the average temperature drops to minus 5-9°C. The highest average temperature of 24-25°C is observed in July. The amplitude of the coldest and warmest months is 29 - 34°C, which indicates a high continental climate.

The region is characterized by east, southeast and northeast winds. In summer they determine high temperatures, dryness and dustiness of the air, in winter - cold and clear weather. Dry winds are associated with these winds from April to August. Winds from other directions bring cloudiness and precipitation. During the year, winds with a speed of 4-8 m/s prevail, but in some cases the speed increases to 12-20 m/s or more. The greatest number of days without wind is observed in summer. Local winds form in our area. In summer, weak breezes blow on the shores of the Caspian Sea: during the day - on land, at night - towards the sea. In winter, the northern part of the Caspian freezes and breezes do not form. Winds blowing continuously for several days from the Caspian side raise the water level on the sea coast and in the Volga delta. Astrakhans call them sailors.

The actual climatic seasons in the region do not coincide with the calendar ones. The criterion for the selection of seasons are the dates of stable transitions of air through certain limits.

Winter in the region begins on November 15 - 20. Astrakhan winter is characterized by unstable weather: clear, cold days are replaced by cloudy, thaws. The coldest month is January with an average monthly temperature down to minus 10°C. The lowest temperature for all the years of meteorological observations was recorded in 1954 in Baskunchak - minus 36°C. The first snow appears in late November - early December. Its thickness is small - only about 5 - 12 cm. Winter is also characterized by a large number of cloudy days. In January - February, strong winds can be accompanied by snowstorms. The average duration of snowstorms is 5-10 hours. During blizzards, the snow cover is transferred, and elevated areas are exposed. On rivers and lakes, a stable ice cover forms in December. Spring is the shortest period of the year, only a month and a half, from mid-March to early May. The air temperature is 0 - 15 ° C, and the heat builds up very quickly. The snow cover is being destroyed, the soil is completely thawing, and ice is breaking up on the rivers. In the second half of April, the flood begins. The birds are returning from the south. In the delta, on the ilmens, swans, herons and other waterfowl build their nests. Fish go to spawn, including the famous Astrakhan vobla. The Astrakhan spring is characterized by the presence of dry periods, when the upper layers of the soil quickly dry out and dusty ones sweep in. Summer is the longest season of the year - 4.5 months. It begins in the first days of May with a steady upward transition of air temperature through 15 ° C and ends in the first half of September, when the temperature drops to 15 C. Clear weather sets in with high temperatures, rare clouds and heavy rainfall. The hottest month is July with an average monthly air temperature of 24-25 °C. Extremely high temperatures were observed in 1949 in Upper Baskunchak - 44 °C. In Astrakhan, the highest temperature was 41°C. In the first half of June, the flood ends. The interim period is coming. The water in the rivers warms up to 24°C, and in the ilmens - up to 25-27°C. In shallow ilmens, not connected at that time with the Volga, the water can completely evaporate, the bottom is covered with a thin layer of salt, cracks, and solonchaks form. Western and north-western winds become more frequent, 37-40% of precipitation falls out of the total annual amount. Precipitation is mainly torrential in nature, thunderstorms are frequent, hail is possible, which causes sufficient damage to crops, salam, vineyards. Often, a kind of thunderstorm arises in the atmosphere: the wind catches up with clouds, the sky is pierced by lightning, thunder is heard, but moisture does not reach the earth's surface, evaporating in heated layers of air. Astrakhans call this phenomenon "dry rain". The beginning of autumn in the Astrakhan region falls on mid-September, when the temperature goes through the mark of +5°C downwards. Warm dry sunny weather sets in with moderately high temperatures during the day and relatively low temperatures at night. Frosts begin in the second half of October. The water in the Volga branches is warmer than the earth's surface, so in the morning the warm air above the reservoirs comes into contact with colder air, fog is formed. It's raining more and more. In the second half of November, winter comes into its own.

Vegetation.

In general, the vegetation cover of the region is characterized by poor species composition. There are a little more than 700 species of higher plants on the territory of the region. Most of them are herbaceous. Few trees and shrubs.

The Astrakhan region is located in two natural zones - a semi-desert and a desert. Some believe that this area is located in the steppe zone, but this is completely wrong. After all, the soils in the steppes are chernozem, but here there are no such soils.

The richest vegetation cover in the Astrakhan region is in the delta of the Volga River and the Volga-Akhtuba floodplain.

The long and hot summer, the abundance of non-saline groundwater, the annual fertilization of flooded places with fertile silt and rich soils cause the rapid development of vegetation. Everything that is not occupied by water is densely covered with various herbs. Plants occupied not only the entire land of the floodplain and delta, but also the shallow areas of branches, eriks, and ilmens. Many shallow waters of the northern part of the Caspian Sea-lake are also covered with lush greenery.

More than 20 species of cereal plants are found on numerous islands in the floodplain and delta. Among them, one of the first places is occupied by creeping wheatgrass, or Arzhanian, as the local population calls it. You can often find bluegrass meadow, white bent grass, canary grass, chicken millet and other meadow plants.

The largest cereal in the floodplain, and especially in the delta of the Volga River, is reed, incorrectly called reeds. Entire islands are often covered with tall reeds. This valuable herbal plant forms impenetrable thickets called krepe. They resemble real grassy jungles of tropical countries. The height of the reed reaches 5-6 meters.

Water-loving plants grow abundantly in rivers, ilmens and on the seashore: cattails, broad-leaved and narrow-leaved, burdock and umbrella susak. Cattail is used for weaving baskets, in cooperage as a cushioning material, in the refrigeration industry as insulation. Juicy rhizomes of cattail, rich in starch, are readily eaten by pigs.

Here, in the neighborhood, at a shallow depth, a water chestnut-chilim grows, in the fruits of which reserves of nutrients are deposited. Chilim fruits are edible raw and cooked. Large areas of the water surface are almost entirely occupied by nymphaeum with yellow flowers, between which water lilies turn white.

The pride of the Astrakhan region is the thickets of lotus - a very rare plant that has survived from the pre-glacial period. Blooming lotus attracts the attention of all nature lovers with its delicate aroma and pale pink hues of large and delicate flowers.

Semi-deserts and deserts adjoin the Volga-Akhtuba floodplain and the delta from the east and west. Every tourist who comes here for the first time is struck by the seeming monotony, monotony and unattractiveness of the vegetation cover. There are no trees or bushes here. So it seems that, except for wormwood, nothing else can grow in these dull places. Even these very unpretentious plants were lost among the bare soil. Lonely lonely blades of wormwood are blown from all sides by sultry ruthless winds. But even such sparse vegetation serves as food for hundreds of thousands of sheep and goats, cows, camels and horses.

With a closer study of these places, the vegetation cover no longer seems boring and monotonous. Throughout the long months of spring, summer and autumn, vegetation in the same place changes more than once.

Immediately after the snow melts and spring rains, the Caspian lowland is covered with a bright green carpet of various short-lived vegetation: viviparous bluegrass, bright red and yellow tulips, annual bushy bonfire grasses and others. These plants are called ephemera. Astragalus blooms in spring, white wormwood grows everywhere. Silky feather grass sways in the wind.

Starting from the middle of May, the general view of the area is changing. The earliest plants complete their development and die. The semi-desert becomes grey-green. White and black wormwood begin to predominate in it. Feathers can occasionally be found only in moist depressions. On the hillocks of Baer, desert wheatgrass turns green.

In autumn, with the onset of cooler and wetter weather, the area comes to life again. Plants quickly grow, bloom and bear fruit. At this time, you can harvest grass for hay of the second cut. Saltwort grows in saline areas. In deserts, the vegetation is even more sparse, it is adapted to an extremely arid climate.

On clayey and loamy soils, black wormwood, saltwort, and ephemera predominate. On salt marshes, saltwort and various types of saltwort grow in abundance. Sandy deserts are represented by semi-fixed areas and waving sands. As a rule, they are richer in water. This is due to the fact that moisture is retained in sands better than in clays. That is why sandy deserts have relatively well-developed vegetation. Here grow couch grass, bluegrass, sandy sedge, sandy wormwood, kachim panicled, prutnyak and many other plants.

There are few forests in the Astrakhan region. They are located mainly in the floodplain and delta of the Volga River. Willows are the most numerous among natural tree species. They form coastal thickets along the banks of the Volga and the ilmens. The sleeves and eriki are, as it were, bordered by corridors - galleries from the forests. There are also a lot of mulberry, poplar and small-leaved elm in these forests. Oak is found in the north of the region.

Every year the area of artificial forest plantations of elm, maple, ash, white locust and other species is increasing. Large forest protection belts have been created along the right and left banks of the Volga for many years. They should weaken the drought and protect nearby fields from the harmful effects of dry winds.

Tamarisk (sometimes called Astrakhan lilac), dzhuzgun and other drought-resistant plants are often found among woody shrubs.

To fix the sands, crops of tall kiyak grass and plantings of Caspian willow are often used.

In general, the vegetation of the Astrakhan region is of great importance in nature and in the economy. Protecting the plants of deserts and semi-deserts, we protect our fields and villages from moving sands. Aquatic plants in the floodplain and delta slow down the flow of water, thereby helping to settle suspended particles and increase the fertility of flooded lands. In such places, fish readily spawn. Forests increase air humidity and lower summer temperatures. Reed beds are a source of cheap raw materials for the production of paper, cardboard, etc. Highly nutritious grasses serve as a fodder base for animal husbandry everywhere.

Soil-forming rocks

The soil cover of the region is formed due to the main soil-forming factors: the underlying surface, relief and climatic conditions, and in recent years - due to anthropogenic influence.

Various types of soils are widespread on the territory of the Astrakhan region. They are represented in the northern regions by zonal light chestnut soils, in the more southern regions - by brown semi-desert soils, in the Volga-Akhtuba floodplain, delta and substeppe ilmens - by floodplain soils. Intrazonal - solonetzes and solonchaks - are found everywhere among all types of soils. The main factor in the formation of soils in the region is the arid climate and sparse vegetation. Light chestnut soils are common on the territory of the right and left banks of the Volga-Akhtuba valley only in the northern part. They occupy the most elevated spaces and are not continuous arrays, but are located in spots, intermittent stripes.

The thickness of the humus horizons of these soils is only 30-40 cm, the amount of humus is small and it is unevenly distributed. Most often, such soils are used for pastures. They are also potentially fertile.

Brown semi-desert soils are located in spots among light chestnut soils and, moving from north to south, with increasing aridity of the climate, gradually expand their areas.

Usually they are confined to leveled spaces, but they can also be found on Baer knolls and other hills. Increased salinity is one of the main reasons for the low fertility of these soils. Salts deposited at depth gradually move towards the surface, resulting in salinization. A small amount of vegetation enriches such soils with little organic matter, and dead plant residues that come to the surface quickly decompose. Brown semi-desert soils are rich in mobile forms of phosphorus and potassium, and the nitrogen content in them is minimal, and therefore such soils require the application of mineral and organic fertilizers. Irrigation is also a prerequisite for this type of soil.

Within the Caspian region, on the territory of the middle and southern parts of the region. have different relief and areas of space occupied by sands. The soil cover has not yet been formed there. As such areas become overgrown with cumarch, sandy oats, and other plants, soils are formed, and sands acquire a number of new properties over time. To fix the sands, various sand-loving plants are planted annually: saxaul, teresken, dzhuzgun. Quite different factors of soil formation take place on the territory of the Volga-Akhtuba floodplain and the Volga delta. Since this part of our area is constantly flooded during high water, fertile silt and solid particles accumulate here.

In the central, most leveled part of the floodplain, the type of alluvial-meadow soils is widespread. In some parts of the floodplain, these soils stand out in the form of large masses.

They are characterized by a high content of humus and are therefore fertile. Grass-forb and sedge-grass-forb meadows are common here. These are the best floodplain soils. Terrace floodplain is not well expressed. The soils of this part of the floodplain contain large amounts of humus, and in composition they resemble brown soils. A sharp transition of the Volga-Akhtuba floodplain into the delta is not observed. The delta occupies a lower position, which causes high moisture caused by longer flooding and the proximity of groundwater, which leads to waterlogging of the soil. Bog soils are accompanied by moisture-loving plants: cattail, reed, susak. These soils are characterized by high humidity, silty composition, bluish-bluish tones. Peat is not formed here, but the products of complete decomposition of organic matter accumulate. Bog soils contain a lot of nitrogen, phosphorus, potassium, but they are used only after special reclamation measures. Soil salinization increases in the delta. The extreme degree of soil salinity leads to the formation of solonchaks. Salts not only permeate the entire soil profile, but even accumulate in the form of a white coating on the surface or even a crust.

A wide variety of soils is observed on the territory of the Western ilmen-bump plain. Here, between the Baer knolls, on which brown semi-desert soils are common, in the depressions between the mounds, elmen-marsh, ilmen-meadow soils are widespread. They are formed during periodic flooding of ilmens during floods. Due to the fact that an insufficiently large amount of water enters some ilmens, the bottoms dry out and salt marshes form.

Soil protection in the region is one of the main tasks. It is connected with human economic activity. Soil salinization occurs, pastures decrease, fertility is lost.

The relief of the Astrakhan region

The territory of the Astrakhan region in tectonic terms is located within two platforms: a significant part is confined to the Precambrian East European platform, the southernmost - to the epi-Hercynian (supra-Hercynian) Scythian. Between them there is a transitional strip, which is called the platform junction zone.

The plain surface, formed under the influence of endogenous processes, is complicated by landforms that were formed under the influence of wind, flowing waters, physical weathering, and others. In its external appearance, the plain is gently inclined towards the Caspian Sea.

By origin, two types of plains are distinguished on the territory of the region: accumulative and denudation. The main background on the territory of the region is created by accumulative plains. Only in the north-eastern part of the region in the vicinity of Lake Baskunchak is a denudation plain. The composition of the accumulative plain includes the sea plain. The most remarkable form of this plain is the mounds. These landforms were first described in 1856 by Academician K.M. Baer and became widely known as Baer's hillocks. Their length is 0.8 - 5 km, width 0.1 - 0.5 km, absolute marks vary from minus 20 to minus 5 m. Roads are laid along the tops of the Baer hillocks, and the hillocks themselves are used for melons.

Lakes - ilmens are located between the ridges of hillocks and have a length from several hundred meters to several kilometers, a width - mainly several hundred meters, an average depth - 1-1.5 m. In the northern part of the region, along the steep right bank of the Volga River, a ravine relief develops.

On the aeolian plain, which is also part of the accumulative plain, there are areas of active dispersal of the dune type, devoid of vegetation.

The dunes have a crescent shape and an asymmetric structure: the windward slope is more gentle, the leeward slope is steep. The surface of the dune is covered with wind ripples. The height of individual dunes reaches 10-15 m. Connecting with each other, they form arrays of several hundred square meters. The formation of dune sands is often due to the fact that a person destroys vegetation, the root system of which strengthens the sands, preventing the process of dispersal.

The floodplain-delta plain, which belongs to the accumulative plain, is located within the Volga-Akhtuba floodplain and the Volga delta. The floodplain occupies a low-lying area between the Volga and Akhtuba, which is flooded with river waters during floods. A green oasis 22-30 km wide, in some places 40-45 km stretches the floodplain among the surrounding territories scorched by the sun. The right bank of the Volga is steep, actively washed away by waters, destroyed during floods, the left bank is gentle, smoothly passes into the island surface of the floodplain, covered with lush meadow and woody vegetation. As you move south, the floodplain turns into a delta. The Volga delta has the appearance of an almost regular triangle with a peak near the village of Upper Lebyazhye, where the high-water branch of the Buzan departs from the main riverbed. The western boundary of the delta is the Bakhtemir branch, and the eastern boundary is the Kigach. The length of the sea edge of the delta is more than 200 km. To the south of it stretches a vast shallow seashore - fore-delta (underwater part of the delta). The floodplain and delta are characterized by a large number of oxbow lakes, in the southern surface part of the delta - kultuks. The relief of the floodplain-delta part is very dynamic, undergoing certain changes every year: some rivulets die off as a result of shallowing, others arise; the outline of coasts, islands changes; new shoals, middles, islands appear.

The denudation type of the plain is located in the northeastern part of the region on the territory adjacent to Lake Baskunchak. The highest precisely of this plain is Mount Big Bogdo, which has an asymmetric structure, steep steep slopes from the east, southeast, north and more gentle western ones. In a hot arid climate, physical weathering and wind play an important role in relief formation. Physical weathering is the destruction of rocks in an arid (hot, arid) type of climate due to large daily temperature amplitudes and low rainfall. As a result of physical weathering and wind, even the most dense rocks are destroyed, and in place of a thick pack of these rocks, bizarrely shaped remains of destruction are formed, on the vertical walls - cellular, similar to bee honeycombs.

On the denudation plain, gypsum comes close to the surface and undergoes leaching. There is a karst process of relief formation. Especially close to the surface or even on the surface, gypsum comes out in the area northwest of Lake Baskunchak. Here karst sinkholes and caves are formed. In terms of funnels, they are oval or round in shape, their dimensions vary widely: depth - from several meters to 15-20 m, diameter - from 1 to 40 m. At the bottom of some funnels there are failures, on the slopes there are entrances to caves, karst wells. The largest cave Bolshaya Baskunchakskaya has a length of more than 1.5 km. It consists of a number of grottoes, interconnected by galleries, has small branches.

Soil classification in the Astrakhan region

Soil and soil cover perform a variety of functions. First, it is the provision of life on Earth. When soil is formed from rocks, chemical elements necessary for organisms accumulate in it. It is from the soil that plants, and through them animals and humans, receive the necessary elements of mineral nutrition and partly water to create their biomass. The soil can perform this function due to a special property - soil fertility, the ability to regularly supply plants with water, mineral nutrients and at the same time create favorable conditions for their life.

Secondly, it is the maintenance of a constant interaction of large and small cycles of substances on the earth's surface.

Thirdly, the soil regulates the chemical composition of the atmosphere and hydrosphere. She, like a sponge, is all riddled with pores and thanks to this she constantly exchanges various gases with the surface atmosphere. The chemical composition of i-runt, river, lake waters is also a consequence of soil processes.

Fourth, the soil regulates biospheric processes, in particular, the density of living organisms on earth.

Fifth, it is the accumulation of active organic matter (humus) and the chemical energy associated with it on the land surface. It is humus that allows the soil to retain nutrients in a form accessible to plants.

All these soil functions are also manifested in the territory of the Astrakhan region. The soil cover of the region is formed due to the main soil-forming factors: the underlying surface, relief and climatic conditions, and in the last decade - due to the light of anthropogenic influence. The underlying surface in this area is a thick layer of sedimentary rocks. At the same time, one should take into account the important role of repeated transgressions and regressions of the Caspian Sea in the formation of the modern relief. Hence, the parent rocks on which soil formation takes place are marine, deltaic, lacustrine, eolian and alluvial sediments of the Quaternary time of various mechanical composition. In terms of climatic conditions, the region is the driest part of Europe with features of sharp continentality.

Zonal light chestnut and brown soils belong to the group of arid gypsum-lime soils. They are formed under the influence of the same process of soil formation, which caused the appearance of similar external features.

The main factors of soil formation for light chestnut and brown semi-desert soils are arid climate (especially high temperatures during the growing season) and xerophytic, sparse vegetation.

Alluvial soddy saturated soils are most widespread (up to 50%) in the floodplain. In terms of genetic age, they tend to be the youngest soils. They are distributed on the floodplain of high and middle levels, which is morphologically associated with the riverbanks of large watercourses and areas of the ridged central floodplain.

Alluvial soddy saturated steppe soils
formed on alluvial deposits with a low content of finely dispersed material. Visually, thin (1-2 cm) layers of alluvium, predominantly brown tones, are clearly visible. Often, from a depth of 60-120 cm, buried humus horizons are found, both horizontally layered and cross-layered. The herbage is dominated by xerophytes. Sod is weak and weak. Flooding is not annual, short-term. The degree of introduction of organic matter with flood waters is minimal. The type of water regime is effusion. The level of mineralized groundwater during the low-water period is at a depth of 2.5-3.0 m. The soils are saline with water-soluble salts throughout the profile, the type of salinity is chloride-sulfate and sulfate. Salts are visually detected in the form of veins and dots. Alluvial soddy saturated layered soils
formed in the zone of medium levels of the meander small ridge floodplain. The herbage is forb-grass, on elevated manes - with an admixture of xerophytes. The type of water regime is mixed: during the period of the flood, by name-leaching, at the end of summer, effusion. The level of groundwater directly depends on the flood regime, the composition of the underlying rocks and the presence or absence of natural drainage of the territory. During the low-water period, the groundwater level is found at a depth of 2-2.5 m. The waters are mineralized, so 60-70% of these soils are subject to salinization with water-soluble salts throughout the profile. Salt underlying rocks are the source of salts. The type of salinity is sulfate, chloride-sulfate. Often a weak degree of solonetzization is found. Alluvial soddy saturated dark-colored soils
formed on leveled areas of the central low-level floodplain under couch grass-forb vegetation. The formation of these soils is significantly affected by the accumulation of fine fractions of mineral and organic suspensions from flood waters. This determines the high content of humus in horizon A, its good structure and dark color. Layering is almost invisible visually. The flooding is long-term flooding, the speed of watercourses is minimal. The type of water regime is floodplain-leaching, changing to effusion. During a period of significant desiccation, soils strongly crack, which further accelerates the loss of moisture from deep layers. This sometimes leads to the appearance of merged horizons of a large block structure. The level of mineralized groundwater during the low-water period is noted at a depth of 2-4m. More than half of the area of the described soils is subject to salinization by water-soluble salts. The type of salinity is chloride-sulfate and sulfate-chloride. Solontsized soils are sometimes distinguished. Alluvial meadow saturated soils are second in distribution after soddy soils. They were formed on finely dispersed alluvial deposits under meadow and wet-meadow vegetation under conditions of excessive moisture. The soils are located on a low-level floodplain, often in flat-bottomed drainless depressions.

Alluvial meadow saturated layered soils
formed on heavy loamy and clayey alluvial deposits. According to the morphological structure, these soils are close to soddy stratified soils. The basis of the herbage is made up of sitnyag, bison, sedges, marshmallows. The flood is prolonged. Complete drying of the profile occurs at the end of summer. The surface of the soil is cracking. The type of water regime is by name-leaching. The level of low-mineralized groundwater in the low-water period is located at a depth of 0.8-1.4 m. Sometimes soils are subject to solonchak salinization, the type of salinization is predominantly sulfate. Visually, salts are detected only with a significant drying of the soil profile. Alluvial meadow saturated dark-colored soils were formed on leveled wastewater and less often drainless areas of the low floodplain. Soils were formed under conditions of excessive flood moisture under meadow and wet-meadow vegetation. The soils are well developed, with pronounced differentiation into genetic horizons. According to the morphological structure, they are close to dark-colored soddy soils. Flooding is prolonged, complete drying of the profile occurs at the end of summer. The type of water regime is floodplain-saline, the type of salinity is chloride-sulfate and sulfate. The groundwater level in low water is set at a depth of 0.8-1.5 m.

Alluvial meadow-marsh soils develop under conditions of excessive flooding in closed depressions.

Soil-forming rocks are lacustrine-alluvial deposits of heavy granulometric composition. Due to the slow drying after the flood, the soil profile remains wet for a long time.

The vegetation cover is represented by reed-cattail communities. Soils are rarely saline. The groundwater level in low water is set at a depth of 0.6-0.8 m.

Meadow solonchaks develop on the low-level floodplain along closed depressions. The source of salinity is saline underlying rocks. Morphologically, meadow solonchaks differ little from the surrounding meadow soils. The degree of salinity is very strong. The type of salinity is usually sulfate-chloride, chloride.

The soil cover of the desert and semi-desert parts of the study region was formed under conditions of an acute deficit of atmospheric precipitation under sparse xerophytic vegetation. Soil-forming rocks on brown soils are Khvalyn deposits, on sands - modern eolian deposits. According to the granulometric composition, soil-forming rocks are represented by sands and sandy loams. Groundwater occurs at a depth of more than 10 m and does not take part in the process of soil formation. Salinization by water-soluble salts in these soils is extremely rare. In the study area, two contours of brown semi-desert soils with a low degree of salinity were identified. The only exceptions are sor solonchaks, which have a very high degree of salinity. The latter were formed along flat depressions, which are the dried bottoms of salt lakes (sors).

Brown semi-desert soils are a zonal type of semi-desert and desert soils. The main climatic factor that determines the direction of soil formation in this zone is high air temperatures and lack of moisture during the growing season. The main features of these soils are low humus content and low thickness of the humus horizon, which is determined by the specifics of the climate, low biological productivity of the vegetation cover, and high microbiological activity.

Brown semi-desert soils in most cases occur in combination with semi-desert sands. The percentage of participation of brown soils is from 10 to 90%. In the study area, we identified a three-member complex, including brown semi-desert soils, semi-desert sands, and sor solonchaks.

Semi-desert sands are located on the background brown soils in the form of closed spots of various sizes. According to the degree of deflation, fixed and weakly fixed sands are distinguished. Large areas of land occupied to varying degrees by deflated sands were found in the study area. They are represented by winnowed sands. Groundwater is located at a depth of 10 m or more and does not take part in soil formation processes. Frequent winnowing of sands does not allow the formation of a differentiated profile. Usually in the upper part there is a layer of freshly blown yellow sand, slightly compacted, structureless, 5-10 cm thick. In the form of inclusions, undecomposed remains of plants and small fragments of mollusk shells can be found. Below are weakly stratified deposits of yellow color, more compacted than the upper layer, structureless, with inclusions of fragments of mollusk shells. The sands are poor in humus, the upper root layer contains no more than 0.3-0.4%.

In the described areas, fixed sands occur in combination with weakly fixed and windy sands and in combination with brown semi-desert soils. Separate pockets reveal windy sands, on which vegetation is almost completely absent.

Salt marshes are semi-desert and desert. These soils develop along flat-bottomed drainless depressions. All solonchaks are confined to saline rock outcrops, or there is a close occurrence of highly mineralized groundwater.

They belong to the subtype of hydromorphic solonchaks, also called sor soils due to the peculiarities of their formation. Often they are located on the bottoms of periodically drying semi-desert lakes.

The structure and properties of soils in the Astrakhan region

According to the mineralogical composition, Astrakhan soils are rich in polymineral carbonates and therefore contain a sufficient amount of elements of ash food (calcium, potassium, phosphorus, sulfur, etc.). According to the mechanical composition, these soils are fine and fine-grained (fractions of 0.25-0.10 mm and 0.10-0.05 mm predominate), which causes their high moisture capacity. Astrakhan soils are excellent pastures with valuable fodder vegetation.

Soil use, methods of increasing fertility in the Astrakhan region

Without exception, all the soils of the desert part of the region have a high degree of deflationary danger. In this regard, any economic activity in the zone of distribution of these soils should be strictly regulated. When grazing farm animals, it is necessary to comply with the norms of pasture load and grazing technology (by seasons and duration). In addition, it is necessary to carry out surface improvement of pastures, which primarily involves overseeding high-yielding grasses.

The most fertile soils of the Volga delta and the Volga-Akhtuba floodplain. This is the main fund of agriculture in the region. The most favorable for development under irrigated agriculture are: meadow layered, meadow and meadow-forest soils (medium and heavy loamy). During the development of these soils, minor work will be required to level the surface. They can grow rice, various garden and horticultural crops.

The use of saline soils is associated with great difficulties and is unprofitable.

In the areas of distribution of Baer hillocks and ilmens, a peculiar soil cover has developed, where brown desert-steppe soils of Baer hillocks and ilmen-meadow, meadow-marsh soils of ilmens alternate. Terraces of ilmens are occupied by meadow-gray ilmen soils. When the ilmens dry out, the desert-steppe process of soil degradation develops here. When drying ilmens, on the bottoms of which solonchaks are not formed, the progress of degradation is superimposed directly on the ilmen-marsh soils.

The bottoms of drying and drained ilmens can be used for firth irrigation of wheatgrass hayfields or for sowing grain and industrial crops. At the same time, it should be borne in mind that without a deep catchment, irrigation will sooner or later lead to soil salinization. The use of ilmen terraces and Baer mounds for irrigated agriculture is quite possible provided that special crop rotations and machine distribution of irrigation water are introduced.

In the central regions of the region, brown soils with massifs of sand prevail, which in the north of the Baskunchak-Kharabala and Sarninskaya plains are replaced by light chestnut soils. These soils are characterized by a low thickness of the humus layer (10–45 cm), a silty structure, and solonetzic to varying degrees.

Brown soils have good water permeability, but low moisture capacity, contain little humus (1-2%) and nutrients.

Light chestnut soils with sufficient moisture give a good harvest of herbs, vegetables, grains and other agricultural crops. Brown soils are more often used as pastures, but with irrigation it is possible to cultivate gourds and grapes.

Light chestnut and brown soils, characterized by a low content of humus, will respond positively to the introduction of fertilizers into them. It is necessary to apply manure or compost and bacterial fertilizers, and the plowing of green fertilizers is also desirable. The value of the irrigation rate is 750-800 m3/ha, the length of the irrigation furrows is 75-100 m. With the development of sandy loamy varieties of the soils under consideration, the rate of irrigation decreases with its frequency.

Thus, most of the soils of the Astrakhan region, with proper irrigation, can be involved in agricultural production. Agrochemical studies have shown that irrigation of lands with a complex soil cover without leveling fertility, optimizing the water-physical properties of soils is not very effective. Alignment of these properties is achieved by reclamation of solonetzes, carrying out planning work with preliminary heaving of the upper humus horizon.

relief saline climate zone

Bibliography

1. Voronin N.I. Features of the geological structure: Monograph. / Astrakh. state tech. un-t. Astrakhan: Publishing House of ASTU, 2004. - 164 p.

Vostryakov A.V. Neogene and Quaternary deposits, relief and neotectonics of the southeast of the Russian Platform. - Publishing House of Saratov University, 1967. - 354 p.

Golchikova N.N. Assessment of the state of the natural environment of the North-Western Caspian: Monograph. / Astrakhan. State. Tech. Univ. - Astrakhan: Publishing House of ASTU, 2005. - 148 p.

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Geography

Astrakhan region, located in the south-west of our country, on the territory of the Caspian lowland.
The geographical position of the Astrakhan region is very favorable. It is located on the border of Europe and Asia, the Volga gives access to 5 seas, being a link between the North Caucasus and the south of Russia, between Kazakhstan and Central Asia, through the Caspian Sea it connects Russia with the Iranian direction. The length of the territory from west to east between Kalmykia and Kazakhstan is 120 km, and from north to south along the Volga and Akhtuba to the Caspian Sea - 375 km. The total area of the region is 44,100 km2, which is 0.3% of the territory of the Russian Federation. In the east, the region borders on Kazakhstan, in the north and northwest - on the Volgograd region, in the west - on the Republic of Kalmykia.
The extreme northern point is located on the border with the Volgograd region at 48 ° 52 "northern latitude, the southern one is on the coast of the Caspian Sea - 45 ° 31" northern latitude. The westernmost point is located in the Chernoyarsk region on the border with the Volgograd region - 44°58" east longitude, the eastern one is on one of the small islands of the Volga delta in the Volodarsky region at 49°15" east longitude.
Surface waters. Rivers flow through the region. The Volga and the branch branching off from it near Volgograd - r. Akhtuba, connected by a large number of ducts. The space between the Volga and Akhtuba is called the Volga-Akhtuba floodplain. At the mouth, the Volga is divided into many branches that form its complex delta. The largest of them are Bakhtemir, Bolda, Buzan and others. There are many salt lakes in the region; fresh lakes (ilmeni) are numerous in the floodplain and delta of the Volga. Delta River The Volga is one of the largest deltas in the world and occupies over 24 thousand square meters in the Caspian lowland. km. The length from north to south is 120 km, along the sea edge of the delta - 200 km.

Climate

The climate of the region is characterized as sharply continental, arid, despite the proximity of the sea. The main amount of precipitation (70-75%) falls during the warm season. Average temperatures in January are from -6 to -10 °C, in July 24-25 °C. The maximum is 42°C, and the minimum sometimes reaches -30°C. The annual amount of precipitation ranges from 180 - 200 mm in the south to 280 - 290 mm in the north. The main amount of precipitation (70 - 75%) falls in the warm season. During the year, winds with a speed of 4 - 8 m/s prevail, but in some cases the speed increases to 12 - 20 m/s and more. About 70% of the territory of the region is occupied by deserts and semi-deserts.

Administrative-territorial structure

The region includes 11 rural districts (Akhtubinsky, Volodarsky, Enotaevsky, Ikryaninsky, Kamyzyaksky, Krasnoyarsky, Limansky, Narimanov, Privolzhsky, Kharabalinsky, Chernoyarsky), 6 cities (of regional significance - Astrakhan, Akhtubinsk, Znamensk), regional significance (Kamyzyak, Narimanov, Kharabali ) 442 villages and settlements.

Population

Multinationality, remaining to this day a distinctive feature of the Astrakhan region, left its mark on its economic and cultural development.

The Astrakhan region is distinguished by a variety of ethnic composition. More than 100 nationalities live on its territory. There are about 20 denominations here.
Urban dwellers 67.9%
The average density is 22.8 people. per 1 sq. km

Flora and fauna

The flora of the region is currently rather poorly studied and, according to various sources, there are from 800 to 1500 plant species.

405 species of higher vascular plants of 258 genera and 82 families grow on the territory of the Volga-Akhtuba floodplain and the Volga delta, including 240 perennials, 134 annuals, 31 biennials and 17 chamephytes. Dominant in the Volga delta are Compositae, cereals, haze, legumes, cabbage, sedge. These families make up 50% of the total flora of the Volga delta.

There are more than 290 plant species in the lower reaches of the Volga Delta. Among them: relic salvinia and chilim, lotus. Up to 50 species of fish live here: among sturgeons - beluga, sturgeon, stellate sturgeon; among herrings - Caspian shad, Volga herring, black-backed; among cyprinids - vobla, bream, carp, rudd, asp, sabrefish, golden crucian carp; as well as - pike, pike perch, perch, gobies, stickleback, etc.

There are few mammals: wild boars, wolves, foxes, otters, field mice, baby mice, etc. Saiga, rodents, eagles are common in the semi-desert. The Volga delta is characterized by white herons and pelicans. Migratory waterfowl are numerous in spring and autumn. The region is inhabited by about 270 species of birds, of which 30 are listed in the Red Book of Russia, about 60 species of mammals, of which 3 are listed in the Red Book of Russia, 18 species of reptiles and 4 species of amphibians.

The total area of forest fund lands in the region is 263.3 thousand hectares. The forested area is 86.5 thousand hectares, the rest of the forest fund lands are mainly occupied by sands and wetlands. The forest cover of the region is 1.8%. All forests belong to the first group and perform mainly: water protection functions - 127.3 thousand hectares; protective functions - 30.3 thousand hectares; sanitary-hygienic and health-improving functions - 38.9 thousand hectares; special purpose - 66.8 thousand hectares.
The total area of tree and shrub vegetation, not included in the forest fund, is 24.7 thousand hectares.
The species composition of forest plantations of the region is not rich and is represented by oak, elm, maple, ash, tree and shrub willow, poplar, saxaul, sucker, mulberry, tamarisk, dzhuzgun. However, the main areas are occupied by willow (33%) and poplar (22%). More than 20% of the area is occupied by forest plantations of ash, elm, tree willow and Euro-American varieties of poplar.

Economy

Due to favorable natural conditions, Astrakhan is a developed agricultural region (the main branches of agriculture are rice, cereals, vegetable growing, melon growing, meat and wool sheep breeding, meat and dairy cattle breeding). The region has a developed mining and fish processing industry. At present, the sectors that are strategically important for the entire country, primarily the exploration and production of hydrocarbons on the Caspian shelf, shipbuilding, and transport, have acquired the greatest importance in the development of the region's economy. In view of the developed industry for the extraction of hydrocarbons, a number of petrochemical enterprises operate in the Astrakhan region.
There are 16 shipyards in the Astrakhan region.

Geography of the Astrakhan region

The Astrakhan region is located in the southeast of the East European Plain within the Caspian lowland, in temperate latitudes, in the zone of deserts and semi-deserts. The region stretches in a narrow strip on both sides of the Volga-Akhtuba floodplain at a distance of more than 400 km.

The extreme northern point is located on the border with the Volgograd region at 48 ° 52 "northern latitude, the southern one is on the coast of the Caspian Sea - 45 ° 31" northern latitude. The westernmost point is located in the Chernoyarsk region on the border with the Volgograd region - 44°58" east longitude, the eastern one - on one of the small islands of the Volga delta in the Volodarsky region at 49°15" east longitude. The main landscape of the region is represented by a gently undulating desert plain complicated by huge massifs of mounds, sands, dry hollows, lakes, karst landforms, etc.

The modern absolute mark of the Caspian Sea is located at a level of 27 m below the level of the World Ocean. To the north, the absolute elevations of the surface increase and in the northernmost part of the region reach plus 15 - 20 m. The highest point is Mount Big Bogdo - 161.9 m, located in the northeast of the region.

The region is assigned to the second time zone, like Moscow, although local time in Astrakhan is ahead of Moscow by 42 minutes.

The region belongs to the Volga region, the Southern Federal District. The geographical position of the Astrakhan region is peculiar. It is located on the border of Europe and Asia, the Volga gives access to 5 seas.

The climate of the Astrakhan region

Our region occupies almost the middle position between the equator and the North Pole. The longest day in our region: in the south its duration is 15 hours 42 minutes, in the north 16 hours 09 minutes. In winter, the shortest day in the region is December 22, its duration is 8 hours 42 minutes in the south, 8 hours 18 minutes in the north.

The duration of the period with temperatures above 0°C is 235-260 days.

An important role in climate formation is played by the position of the region relative to the World Ocean. The region is located in the temperate zone, which is characterized by the transfer of air masses from the Atlantic Ocean to the west. Often, air masses break into the territory from the Arctic Ocean, sometimes from the Black and Mediterranean Seas. But all these reservoirs are located quite far from our region. The influence of the Atlantic Ocean is associated with the arrival of cyclones, and, consequently, precipitation, a decrease in temperature in summer and an increase in winter. With the advent of the Siberian anticyclone, pressure rises in the region, cloudiness and the amount of precipitation decrease. Therefore, in winter, under conditions of short days and clear skies, low temperatures are set. In summer, this cyclone causes an increase in air temperature and leads to the establishment of hot days.

The average annual air temperature varies from south to north from 10°С to 8°С. The coldest month is January, the average temperature drops to minus 5-9°C. The highest average temperature of 24-25°C is observed in July. The amplitude of the coldest and warmest months is 29 - 34°C, which indicates a high continental climate.

East, southeast and northeast winds are typical for our region. In summer they determine high temperatures, dryness and dustiness of the air, in winter - cold and clear weather. Dry winds are associated with these winds from April to August. Winds from other directions bring cloudiness and precipitation. During the year, winds with a speed of 4-8 m/s prevail, but in some cases the speed increases to 12-20 m/s or more. The greatest number of days without wind is observed in summer. Local winds form in our area. In summer, weak breezes blow on the shores of the Caspian Sea: during the day - on land, at night - towards the sea. In winter, the northern part of the Caspian freezes and breezes do not form. Winds blowing continuously for several days from the Caspian side raise the water level on the sea coast and in the Volga delta. Astrakhans call them sailors.

The actual climatic seasons in the region do not coincide with the calendar ones. The criterion for the selection of seasons are the dates of stable transitions of air through certain limits.

Spring is the shortest period of the year, only a month and a half, from mid-March to early May. The air temperature is 0 - 15 ° C, and the heat builds up very quickly. The snow cover is being destroyed, the soil is completely thawing, and ice is breaking up on the rivers. In the second half of April, the flood begins. The birds are returning from the south. In the delta, on the ilmens, swans, herons and other waterfowl build their nests. Fish go to spawn, including the famous Astrakhan vobla. The Astrakhan spring is characterized by the presence of dry periods, when the upper layers of the soil quickly dry out and dusty ones sweep in.

Summer is the longest season of the year - 4.5 months. It begins in the first days of May with a steady upward transition of air temperature through 15 ° C and ends in the first half of September, when the temperature drops to 15 C. Clear weather sets in with high temperatures, rare clouds and heavy rainfall. The hottest month is July with an average monthly air temperature of 24-25 °C. Extremely high temperatures were observed in 1949 in Upper Baskunchak - 44 °C. In Astrakhan, the highest temperature was 41°C. In the first half of June, the flood ends. The interim period is coming. The water in the rivers warms up to 24°C, and in the ilmens - up to 25-27°C. In shallow ilmens, not connected at that time with the Volga, the water can completely evaporate, the bottom is covered with a thin layer of salt, cracks, and solonchaks form. Western and north-western winds become more frequent, 37-40% of precipitation falls out of the total annual amount. Precipitation is mainly torrential in nature, thunderstorms are frequent, hail is possible, which causes sufficient damage to crops, salam, vineyards. Often, a kind of thunderstorm arises in the atmosphere: the wind catches up with clouds, the sky is pierced by lightning, thunder is heard, but moisture does not reach the earth's surface, evaporating in heated layers of air. Astrakhan residents call this phenomenon “dry rain”.

The beginning of autumn in the Astrakhan region falls on mid-September, when the temperature goes through the mark of +5°C downwards. Warm dry sunny weather sets in with moderately high temperatures during the day and relatively low temperatures at night. Frosts begin in the second half of October. The water in the Volga branches is warmer than the earth's surface, so in the morning the warm air above the reservoirs comes into contact with colder air, fog is formed. It's raining more and more. In the second half of November, winter comes into its own.

In recent years, the Center for Hydrometeorology and the Committee for Ecology and Natural Resources have carried out systematic observations of air purity. In the city of Astrakhan, the main source of pollution is road transport, which accounts for 50-60% of pollutants. The sources of harmful emissions into the atmosphere include thermal power plants, boiler houses, meat processing plants. On a regional scale, the Astrakhan gas processing plant in Aksaraisk remains the main source of pollution. In recent years, effective work has been carried out to reduce harmful emissions by these enterprises. The qualitative composition of the air largely depends on the degree of landscaping of the territory.

The soil of the Astrakhan region

The soil cover of the region is formed due to the main soil-forming factors: the underlying surface, relief and climatic conditions, and in recent years - due to anthropogenic influence.

Brown semi-desert soils are located in spots among light chestnut soils and, moving from north to south, with increasing aridity of the climate, gradually expand their areas. Usually they are confined to leveled spaces, but they can also be found on Baer knolls and other hills. Increased salinity is one of the main reasons for the low fertility of these soils. Salts deposited at depth gradually move towards the surface, resulting in salinization. A small amount of vegetation enriches such soils with little organic matter, and dead plant residues that come to the surface quickly decompose. Brown semi-desert soils are rich in mobile forms of phosphorus and potassium, and the nitrogen content in them is minimal, and therefore such soils require the application of mineral and organic fertilizers. Irrigation is also a prerequisite for this type of soil.

The floodplain is divided into three parts: riverbed, central and terraced. The near-channel elements of the floodplain are the most elevated points. Alluvial soddy soils are formed here. They are the youngest and least developed, and need protection from being blown away by the wind. These soils are the least valuable, as they contain a small amount of humus. In the central, most leveled part of the floodplain, the type of alluvial-meadow soils is widespread. In some parts of the floodplain, these soils stand out in the form of large masses. They are characterized by a high content of humus and are therefore fertile. Grass-forb and sedge-grass-forb meadows are common here. These are the best floodplain soils. Terrace floodplain is not well expressed. The soils of this part of the floodplain contain large amounts of humus, and in composition they resemble brown soils.

A sharp transition of the Volga-Akhtuba floodplain into the delta is not observed. The delta occupies a lower position, which causes high moisture caused by longer flooding and the proximity of groundwater, which leads to waterlogging of the soil. Bog soils are accompanied by moisture-loving plants: cattail, reed, susak. These soils are characterized by high humidity, silty composition, bluish-bluish tones. Peat is not formed here, but the products of complete decomposition of organic matter accumulate. Bog soils contain a lot of nitrogen, phosphorus, potassium, but they are used only after special reclamation measures. Soil salinization increases in the delta. The extreme degree of soil salinity leads to the formation of solonchaks. Salts not only permeate the entire soil profile, but even accumulate in the form of a white coating on the surface or even a crust.

Soil protection in the region is one of the main tasks. It is connected with human economic activity. Soil salinization occurs, pastures decrease, fertility is lost.

The relief of the Astrakhan region

On the aeolian plain, which is also part of the accumulative plain, there are areas of active dispersal of the dune type, devoid of vegetation. The dunes have a crescent shape and an asymmetric structure: the windward slope is more gentle, the leeward slope is steep. The surface of the dune is covered with wind ripples. The height of individual dunes reaches 10-15 m. Connecting with each other, they form arrays of several hundred square meters. The formation of dune sands is often due to the fact that a person destroys vegetation, the root system of which strengthens the sands, preventing the process of dispersal.

Minerals on the territory of the Astrakhan region

The geological structure of the Astrakhan region led to the formation of various minerals on its territory.

Oil Gas

Until the 30s of the 20th century, separate enthusiastic scientists were engaged in exploration and study of hydrocarbon deposits (oil, gas) to a depth of 300-350 m. The question of the need to start research work was repeatedly raised in the region. On the edge did not have the necessary funds to carry out the work. Only in the post-war years did exploration work begin. In the 1950s, the Promyslovoye gas field was discovered, which made it possible to gasify residential and industrial facilities in the city of Astrakhan and a number of villages.

In August 1976, a fountain that hit from well 5 announced the discovery of the Astrakhan sulfur and gas condensate field, unique in its reserves and composition of components not only in Russia, but also abroad. The field is located 70 km northeast of the city of Astrakhan (Aksaraisk). The area of the deposit is 2500 sq. km. The produced gas is processed at the Astrakhan Gas Processing Plant (AGPZ Astrakhan-Gazprom). In 1990-1991, the Verblyuzhye oil and Severo-Shadrinskoye gas fields were discovered, which are now in the stage of detailed study.

Salt

One of the world's largest deposits of high-quality table salt is connected with Lake Baskunchak. It contains 98% sodium chloride and is considered one of the best in the world.

In captivity, the lake has an irregular shape. In its general appearance, the lake resembles the head of a dog, which means the word "Baskunchak" in Turkic. The lake is fed by shallow underground waters, the water-resistant layer of which is rock salt. Groundwater dissolves salt, turns into brine and flows out to the surface of the lake in the form of springs. Annually springs take out 800-900 thousand tons of salt. The salinity of an aqueous solution of salt (brine) is 300 ppm. Rapa covers the surface of the lake by 0.5 - 0.7 m only in the cold season, after precipitation, snowmelt. In summer, water evaporates, salt in the form of crystals settles on the surface of the lake. Salt occurs to a depth of 600 m. The salt layer alternates with layers of clay and sand.

Three varieties of salt are mined: novosadka, grenade (loose mass of crystals) and cast iron (dense stone mass that has to be ground). Baskunchak salt makes up 80% of all Russian salt. Therefore, Lake Baskunchak is rightly called the All-Russian salt shaker.

Construction Materials

A special role among the deposits of building materials belongs to Russia's largest gypsum deposit Baskunchak. Gypsum is mined in a quarry up to 40 m deep with blasting. The blocks that collapsed after the explosion are transported by trucks from the quarry to the surface, where they are further processed.

Clays and loams are used for brick-tiling and expanded clay production. For the production of bricks and tiles, 18 deposits have been developed, on the basis of which several brick factories operate. For the production of silicate products, two large sand deposits are used: Streletskoye and Volzhskoye. Kubatau limestone deposit is located 5.5 km east of Lake Baskunchak, from which building lime is produced. Also, in the vicinity of Lake Baskunchak, outcrops of mineral paints were found, represented by coloring ocher clays of the Triassic. They are suitable for the manufacture of lime-cement paints and as a pigment for dry and oil paints.

The region has huge reserves of mineral waters and therapeutic mud, which are waiting for their detailed study and development. At the moment, the Tinaki mud-healing resort is open in Astrakhan.

Water resources

The surface waters of the region are represented by the Volga River, its branches, as well as many channels, erics, fresh, salt lakes and the largest lake on our planet - the Caspian Sea.

The Volga River, the longest in Europe, stretches for 3,530 km and has a drainage basin of 1,360,000 sq. km.

Information about the Volga is found in the works of scientists and travelers of ancient times. The first mention of it as the river Ra is in the records of the Greek Ptolemy in the 2nd century. n. e. Later, in the 9th and 10th centuries, Ra acquires the name Edil, but more often Itil. At the end of the 14th - beginning of the 15th century, the river became the most important trade route from Europe to the countries of the Caucasus, Central Asia, Persia, and India. In the second half of the 15th century, the Tver merchant Afanasy Nikitin traveled along the Volga through the Caspian Sea to India, about which he wrote in the book "Journeys Beyond the Three Seas".

Around that time, its former name was assigned to the Volga. Scientists suggest that it comes from the old Russian word "vologa" - moisture. Various travelers traveling along the Volga left its description and interesting information about it. (Adam Olearius in the 17th century, P.S. Pallas, S.G. Gnelin in the 18th - 19th centuries).

K.M. Baer, after traveling along the Volga, explained an interesting planetary feature: the great steepness of the right bank of the river in the northern hemisphere and the left - in the south under the influence of the deviating force of the Earth's rotation (Baer's law). above sea level. For the first few tens of kilometers, the Volga is a thin stream, and only after the Selizharovka River flows into it does it become a full-flowing river. The Volga, the Caspian Sea, and other rivers flowing into it belong to an endorheic basin. The connection of the Volga with the oceans is carried out through a shipping channel located near Volgograd.

The Volga, almost along its entire length, has been turned into a chain of reservoirs passing into each other, 8 cascades of hydroelectric power stations have been created on it. Only from Volgograd to the Caspian Sea, the Volga has retained its natural appearance, but even here the natural regime of floods is violated.

On the territory of the Astrakhan region, the Volga does not receive a single tributary. At the Volzhsky, a large branch is separated from it to the east - the Akhtuba River, which flows parallel to the main river throughout its entire length. The low-lying space between the Volga and Akhtuba is flooded with flood waters and is called the Volga-Akhtuba floodplain.

To the north of Astrakhan, where the large branch of Buzan separates from the Volga, a delta begins. The largest branches of the delta are Bakhtemir, Kizan, Straight and Curved Bolda. The main branches 0.3 - 0.6 km wide branch into numerous channels and eriki. The basis of the hydrological network of the delta is formed by eriki - small watercourses up to 30 m wide. At the confluence with the Caspian, the Volga has about 800 mouths.

The Volga is fed by melting snow. Rain and ground feeding make up an insignificant share.

The Volga is characterized by spring-summer floods. The construction of the dam in the Volgograd region caused a decrease in the level of high water, a decrease in its duration. The average volume of spring flood decreased from 130 to 97 cubic meters. kilometers, in duration - from 83 to 53 days.

The spring flood begins in the second half of April, peaking at the end of May - beginning of June. Water rises by 2-4 meters and fills huge spaces - hollows. The water in them warms up well, and the hollows serve as the main spawning grounds for many types of fish: carp, bream, roach and others. During a short-term flood, juvenile fish do not have time to leave the hollows and die. The speed of water flow in large channels varies between 0.8 - 1.5 m / s, reaching 2-2.5 m / s in high water.

The Volga and its main branches have an average depth of 8 - 11 meters, but in some areas pools 15 - 18 meters deep are formed, which Astrakhans call pits.

In the 17th century, the B. Bolda River was the most full-flowing of the branches, and later - Ivanchug. From the beginning of the 19th century, the Volga itself served as a road to the sea (now called the Old Volga), but later its channel began to be covered with sand, split into channels. The ship's passage was moved to the west - to the Bakhtemir branch, this significance has been preserved to this day. In order to maintain normal conditions for navigation, it is necessary to systematically carry out deepening works along the fairway.

However, the Volga is currently in a deplorable state. The lower reaches of the river concentrate all harmful substances that enter it throughout the drainage basin. 9-10 cubic meters are dumped into the Volga. km of untreated industrial and domestic wastewater. Of the 150,000 rivers, streams and streams that supplied the Volga with water, 30% have disappeared in recent years.

Of all the HPPs, only Volgogradskaya and Saratovskaya have devices for letting fish through, which are quite low-powered and are not able to let through all the fish. And she is dying under the dams.

In recent years, control over enterprises that discharge harmful substances has been tightened. New treatment facilities are being built at a higher technological level. All this will help to avoid the death of the great Russian river - the Volga.

Lakes on the territory of the Astrakhan region

By origin, Astrakhan lakes are divided into tectonic, dammed, mixed, and by chemical composition - into fresh and salty.

Lake Baskunchak belongs to tectonic lakes. It is a trough, the deflection of which is compensated by sedimentation in the form of a salt layer. In terms of the lake has an irregular shape. The length of the lake is 18 km, the width is from 6 to 9 km, the total area is 106 sq. km. The absolute mark of the salt surface is minus 21.3 m.

The northern, western, southern shores are steep, the eastern ones are more gentle, indented by runoff hollows. From the top of the Big Bogdo mountain, the lake resembles a huge silver bowl glowing in the sun.

Lakes - oxbow lakes and kultuks belong to the dam type. The oxbow lakes are widespread in the floodplain and delta. They are horseshoe-shaped in plan and are not connected with the main river or erikom. During the spring flood, they are filled with water, and in the summer they can become shallow until completely dry.

Kultuks are formed at the sea edge of the delta, when bays, due to the accumulation of sandy deposits in the form of spits, shafts from the sea, lose contact with it and turn into lakes. Kultuks are shallow (0.5 - 1 m), the water in them quickly warms up in summer, is covered with picturesque thickets of nymphaeum, white water lily, chilim, cattail, reed.

Lakes - ilmeni are mainly concentrated to the west of the delta. Wind, sea and Volga waters took part in their formation. After the retreat of the Caspian Sea, the water was preserved only in the deepest areas; the Astrakhans began to call these areas ilmens. The length of the ilmens ranges from several hundred meters to several kilometers. The longest is Big Beshkul - 10 km. Their width is from 150 to 1000 m. Depth in low water - 0.5 - 1 m, in high water - 2 - 3.5 meters. Sometimes the ilmens are interconnected by narrow eriks. As a result, parallel chains of ilmens elongated from east to west are formed, separated from each other by narrow rows of hillocks. Some of the ilmens retain water throughout the year and are freshwater lakes. Lush vegetation grows on their banks, there are a lot of fish in the ilmens, there are crayfish. Ilmeni, which are not filled with water for several years, are in different stages of salinization, up to their transformation into salt lakes. Such reservoirs are surrounded by unpretentious salt-loving vegetation - halophytes. Narrow rows of Baer hillocks stretch between fresh and salt lakes. Salt reserves in salty ilmen lakes are small. But until the 20th century, salt was mined from them. Raspberry Lake is known, which was the property of Empress Catherine II. Every year, 100 pounds of this salt was supplied to her table, and only she was served at the table during foreign receptions, because the salt was an exquisite pink-raspberry color. This color is explained by the fact that Raspberry Lake is inhabited by the microorganisms of salinaria serration, which produce a pinkish pigment.

Not far from the village of Korduan, located on the left bank of the Kigach River, there is the Small Korduan salt lake. Here, for the first time, a mineral called astrakhanite was discovered. It consists of sodium sulfate, sulfur-magnesian salt and water. It grows very slowly: it takes 50 years for it to increase in weight by 1 gram.

Salt lakes of the region are rich in therapeutic mud. On one of these lakes, the Tinaki resort was created, located 15 km northwest of Astrakhan. The resort arose in 1820 on the shores of Lake Tinaki. The lake got its name from the word "mud", as the silty deposits that accumulate at the bottom of the lake are often called. Silts are black creamy mud of increased mineralization, enriched with hydrogen sulfide, and in some lakes also with bromine. Tinak mud is used to treat diseases of the musculoskeletal system and many others. However, after the construction of the Astrakhan Pulp and Cardboard Plant in the immediate vicinity of the resort, the sludge was contaminated with industrial effluents. The use of mud from Lake Tinaki for medicinal purposes became impossible. Now the mud is delivered to the resort from a salt lake located 100 km west of Lake Tinaki.

In fresh ilmens, a specific type of silt deposits with an organic content of more than 15% is also formed, which is called sapropel. It is formed as a result of the accumulation at the bottom of the ilmen, along with mineral substances, the remains of aquatic plants and animals. Sapropel is a valuable organo-mineral approval, improves soil structure, promotes its deoxidation due to the increased content of calcium. Ilmeni with fresh water are sources of water supply, habitat for certain species of plants and animals, a favorite vacation spot for Astrakhan residents.

Caspian Sea

The Caspian Sea is the largest lake in the world, named for its large size as a sea. Its area without islands is 368 thousand square kilometers. The Caspian contains 90% of the water of all salt lakes in the world.

Information about the Caspian Sea is given in the works of ancient scientists: Herodotus (5th century BC), Aristotle, Claudius Ptolemy and others. A comprehensive physical and geographical study of the Caspian Sea begins under Peter 1 and is associated with the names of F.I. Simonova, A.A. Bekovich - Cherkassky, A. Kozhin. The Caspian Sea had about 70 names: Hyrkan, Khvalyn, Khazar. Abeskun, Saray, Sikhay, Derbent and others. The sea got its modern name in honor of the ancient tribes of the Caspians (horse breeders), who lived in the 1st century BC. on the northwest coast.

The Caspian Sea is extended for more than 100 km, its level is 27 meters below the level of the World Ocean. The maximum depth is noted in the southern part and is equal to 1025 m.

According to physical and geographical features, according to the features of the hydrological regime, the Caspian Sea is divided into northern, middle and southern parts. The Astrakhan region is located near the northern part.

The relief of the bottom of the Northern Caspian is a shallow, slightly undulating accumulative plain with a delta, foredelta and a number of islands. Low, gently sloping shores are swampy, covered with impenetrable thickets of reeds up to 3-4 meters high. This part of the pool rarely has a depth of more than 4 meters. For navigation and passage of schools of fish, channels are being built here (Volga-Caspian Canal, Gandurinsky, Kirovsky and others).

Wind plays an important role in the hydrological regime of the Caspian Sea. The average wind speed throughout the year is 3-7 m/s. Strong storm winds are observed from October to April. On the border with land, local winds arise: moraine and breeze. Winds cause drift and katabatic currents. Wave speeds range from a few centimeters to 1 m/s, reaching more than a meter with a wind speed of 24-28 m/s. The height of the waves in stormy weather is usually 2 meters, rarely reaches 4 meters, due to the fact that the northern part of the Caspian Sea is shallow and covered with ice in winter.

At the end of December, ice covers the entire space, and its thickness in some places reaches 40-79 cm. Squall winds break the ice, forming hummocks up to 12 meters high. At the end of March-April, the Northern Caspian is completely cleared of ice. In summer, the water warms up to an average of 24 - 26 C, and in shallow water - up to 35 C. The waters of the Caspian Sea are characterized by a certain mineralization. The average salinity in the northern Caspian ranges from 6 to 11‰ and decreases to 3‰ at the mouth of the Volga. The waters of the Caspian Sea are rich in calcium ions, sulfates, which is due to the closeness of the basin and the influence of large river flow.

The outlines of the Caspian Sea are constantly changing. The sea rose to an absolute mark of 49 m and dropped to minus 50 meters. At the highest water level, the connection between the Caspian Sea and the Black Sea was established through the Kumo-Manych trough. A lot of archaeological excavations testify to the instability of the level of the Caspian Sea. For example, during the construction of a dam under the bottom of the Absheron Bay, at a depth of 1.5 m, skeletons of Scythian warriors buried in the 1st century BC were found in stone tombs. BC.

In the 30s of the 20th century, the sea began to leave. In 1977, the lowest level in the last 300 years was recorded, amounting to minus 29.03 meters. Since 1978, the rise of the Caspian Sea has begun, now its mark has reached minus 27, and the sea continues to rise.

The level of the Caspian Sea may increase by another 4-5 meters compared to today's level due to climatic conditions. Sea water will move inland for tens of kilometers

The flora and fauna of the northern part of the Caspian is very diverse. Here you can meet the inhabitants of both fresh and salt water bodies. The presence of hydrocarbon minerals is assumed in the Caspian shelf zone. But their exploration and development can worsen the ecological situation in this region. The development of equipment for the extraction of oil and gas from the Caspian shelf in a safer way is underway.

The groundwater

Groundwater is divided into groundwater and interstratal.

Groundwater is confined to the first aquifer from the surface, located on the first impermeable layer and not covered by impermeable rocks. The aquifer is represented by sands of the modern, Khvalyn and Khazar ages in the north of the region. The depth of groundwater is from a few meters to 20 - 50 m. Most of the water is salty. At the same time, in the area of Lake Baskunchak, the Khazar waters are fresh and are sources of water supply for the village of Nizhniy Baskunchak.

Interstratal waters are located in the aquifers between layers of water-resistant rocks. This type of groundwater can be traced in rocks of different ages throughout the neological size, starting from the Quaternary deposits. For the most part, interstratal waters are characterized by increased mineralization and are recommended for use for medicinal purposes.

Flora and fauna

Vegetation of the Astrakhan region

The species composition of the region's flora is not rich. On the territory of the Volga-Akhtuba floodplain and the Volga delta, as a result of research, about 500 plant species belonging to 82 families have been identified. The richest among these families are the genera of wormwood, pondweed, astragalus, sedge, milkweed and saltwort.

The Caspian deserts are the realm of semi-shrub wormwood, among which the most common is white wormwood, poor-flowered or black wormwood, and sandy wormwood. In total, the genus Artemisia is represented by 10 species. Desert plants as a result of evolution have developed a number of features that allow them to endure the lack of moisture and salinity of the soil. In many species of species, the leaves have changed - the surface area of the leaf has become much smaller. Some have strengthened shoots. As a rule, the underground part of desert plants is 19-20 times more powerful than the above-ground part. Plant species such as soleros, knobby sarsazan, multi-branched tamarix, Gmelin's kermek - salt-loving plants grow here. Ephedra two-eared, thin-legged, feather grass, Schober's saltpeter, gray teresken, giant grate, fescue, desert wheatgrass are typical representatives of the desert fauna of our region. The vegetation cover of the desert is exceptionally dynamic, which is associated with the movement of the soil. In general, the flora of the desert has 160-200 species, and the leading families here are Compositae, haze and cereals.

The plant composition of the Lower Volga valley is closely related to moisture. A sharp change in moisture in the floodplain and delta prevents the spread of forests. They grow only in narrow strips (ribbon or gallery forests) along riverbeds and channels; the main spaces are occupied by meadows. Black poplar, ash, elm and willow are common here. In meadows with little moisture, there are ground reed grass, sorrel sorrel, blueberry, pontic wormwood, Russian bedstraw, horned bird's foot. Wetter meadows are occupied by awnless brome, narrow-leaved bluegrass, madder-shaped bedstraw (in the floodplain) and sea tuber, medicinal marshmallow and other species. Moistened and waterlogged habitats are occupied by acute sedge, broad-leaved marshmallow, southern reed, fence sedge, coastal sedge (in the delta). The coastal region of the delta is dominated by tall reed beds. In the underwater part of the delta, spiral vallisneria, hornworts, urut, pondweeds, and an underwater form of umbrella susak grow. These peculiar "underwater meadows" are an excellent place for the growth and development of many semi-anadromous fish.

The flora of the Caspian Sea differs sharply in species composition from the flora of the underwater part of the delta. The higher plants of the Caspian are represented by only five species. These are seagrass zostera, comb pondweed, sea naiad, spiral rupee and sea rupee. Green, blue-green and diatoms also dominate here, of which there are more than 700 species. In addition to them, golden algae, pyrophytes, euglenoids, brown, char, and red algae are noted in the Caspian Sea. Most of the algae species of the Caspian Sea belong to phytoplankton. These algae are the basis of fish resources.

Also on the territory of the Astrakhan region, medicinal plants grow, of which there are more than 100 species. It is necessary to note the peculiarity of medicinal plants growing in the southern regions of Russia. The closer to the south, the higher the content of active medicinal substances, the stronger the effect they have on the human body. About a third of medicinal plants of the Astrakhan region are poisonous. In small doses, toxic substances have a therapeutic effect, and species containing these substances are also medicinal. These species include: white acacia, leafless anabasis and solonchak anabasis, black henbane, common dope, common kirzan, May lily of the valley and other plants. Many species of medicinal plants are very rare. Harvesting of such plants is impossible and unacceptable. These species include - thyme (thyme), May lily of the valley, walnut lotus, calamus marsh. But not only poisonous medicinal plants grow in the region. There are also non-poisonous individuals: marshmallow officinalis, licorice naked, couch grass, medicinal dandelion, sandy immortelle, gray blackberry, narrow-leaved sucker, wandering pamelia (cut-grass, crow's feet - a popular name).

Cultivated plants are also not uncommon in the Astrakhan region as early as the 13th century, watermelons began to be sown near Astrakhan, from where they spread throughout southern Russia. In the middle of the 20th century, a research institute for irrigated vegetable growing and melon growing was established. Tomatoes are the most widespread crop in the region. Processing plants produce high-quality tomato juice, hot sauce, tomato paste and puree, ketchup and other products. Astrakhan tomatoes enjoy well-deserved fame throughout the European part of Russia. For the first time in the country, the first vineyards appeared in Astrakhan, grapes began to produce raisins, juice, and wine. Recently, rice has become widespread on the territory of the Astrakhan region. Fruit plants also grow here: apple trees, quince, strawberries

Fauna of the Astrakhan region

The fauna of the region is quite diverse. This is facilitated by the peculiar location of the territory and climatic conditions.

First of all, these conditions are favorable for the life of protozoa. In the reservoirs of the delta, there are about 150 species. Badyaga also lives here - this animal belongs to the class of sponges. It has long been used in folk medicine for rubbing bruises, treating radiculitis, rheumatism.

5 species of coelenterates live in the Caspian Sea basin: hydra, American Blackfordia, Black Sea merizia, Balitian boutenvillea, polypodium, and another type of hydra: craspedacusta. Annelids are found in the ground. There are about 10 species of earthworms or earthworms in the soils of the region. Snail and fish leeches are found in fresh water bodies of the delta.

The delta is also home to about 80 species of molluscs. The class of bivalve ones includes toothless, barley, balls, zebra mussels and others. Their body is placed in a shell, which consists of two flaps. All mollusks purify water by filtering it in search of food. One mollusk purifies about 150-200 liters of water per day. Gastropod mollusks, which have a solid tubular shell covering the back of the mollusk, are represented in our region by pond snails, clams, river livebearers, physas, coils, meadowsweet .. About 260 species of crustaceans live in the Northern Caspian. The most common representatives: daphnia, copepods crayfish, mysids, gammarids, cumaceans and others. Narrow-toed crayfish is the only representative of decapod crayfish in the Volga delta.

Arachnids have chosen the surface layer of the atmosphere and the surface layer of the soil for their habitat. They can be found in the forest, steppe, desert, field, living quarters. Large salpugs, motley scorpion, spiders and ticks are found within the region. Karaurt is one of the most dangerous spiders in Russia, its venom is 15 times more toxic than that of a rattlesnake. About 6% of those bitten die. The South Russian tarantula is a spider no less famous in the Astrakhan region .. This is also a poisonous spider, but the bite of a tarantula is not fatal for a person. In addition to karakurts and tarantulas, 6 more species of poisonous spiders live on the territory: black spider, eresus, cross, argiope and others. They cannot cause serious harm to a person. Often there are spiders - side walkers. They deftly jump on the flowers. They do not weave nets, catching victims with a swoop. Some of them feed on plant juices or nectar. The features of the relief and climate of the Astrakhan region favor the life of insects. In total, there are about one and a half thousand species of insects. Terrestrial beetles live in the region: rhinoceros beetle, marble beetle, pimella, odorous beetle, trellised ground beetle, golden and marble beetles. Of the aquatic, one should indicate large and numerous water lovers - large and black, as well as a fringed swimmer. The large water-lover is most often confused in our area with the May beetle. One of the most dangerous for agriculture is an intruder from America - the Colorado potato beetle, which eats potato leaves. and other cultures.

A detachment of bedbugs is represented in the Astrakhan region mainly by waterfowl: the greblyak, the ranatra, the smooth and others. But the most famous representative is water striders.

Order Lepidoptera - butterflies. There are about 140 species of butterflies in the Astrakhan region. The most numerous are: the fiery chervonets, the Icarus pigeon, the argiat, the raspberry, the beautiful pigeon and the silver pigeon - small or medium-sized butterflies. Of the large butterflies, there are numerous: meadow jaundice, cabbage, lemongrass, burdock, cornwing, bears, swallowtail, podalirium and a number of others. The large peacock eye is the largest of the butterflies. Here it is fashionable to meet podalirium, whites, scoops and moths, euphorbia, ruled, bindweed, small wine, poplar hawk and tongue. Our region is also rich in dragonflies. The largest of them are the esna, or simply the yoke, and the anax, the watchman.

Class bony fish - a large group of aquatic animals of the Astrakhan region. If we consider fish that live not only in the Volga, but also in the Caspian Sea, then in total there are 76 species and 47 subspecies. The Astrakhan region has long been famous for sturgeons, which in Russia were called "red" fish. In total, 5 species of sturgeon live here - Russian sturgeon, stellate sturgeon, beluga, spike and sterlet. The first four species are anadromous, while the sterlet is a freshwater fish. Also, a hybrid of beluga and sterlet is bred - bester. Herring species are represented by Caspian shad, common sprat and black-backed and Volga herring. Of the salmon species in the region, there is a white fish, from the pike order, the only representative is the pike. Carp fish of the lower reaches of the Volga include bream, carp, roach, rudd, gold and silver carp, asp, silver bream, gudgeon, grass carp, white and motley silver carp. Perch are represented by river perch, ruff, as well as zander and bersh. The only representative of the stickleback order - the southern stickleback - is found everywhere in stagnant shallow freshwater reservoirs of the lower reaches of the Volga River.

Amphibians occupy an intermediate position between aquatic and terrestrial vertebrates. In the Astrakhan region, only representatives of the tailless detachment live - the lake frog, the green toad and the common spadefoot.

Of the order of turtles, only one species is found in the region - the marsh turtle. And among the lizards, the most common are the agile lizard, colorful and fast lizards, eared round-headed, round-tailed round-headed, takyr round-headed and squeaky gecko. Close relatives of lizards are snakes. These peculiar animals are characterized by an unblinking gaze, a forked tongue, and poisonousness. The group of snakes in the Astrakhan region has 10 species. Common and water snakes, yellow-bellied, four-striped and patterned snakes, verdigris, lizard snake, sand boa, steppe viper and Pallas muzzle live here. The most common types of snakes in the lower reaches of the Volga are ordinary and water snakes.

About 260 bird species can be found within the Astrakhan region. Some (sedentary) can be met all year round, others (migratory and nomadic) - during migrations. The order of passerines includes house and field sparrows, tits - big and blue tit, common thrush, thrushes - fieldfare, black and songbirds, swallows - coastal, urban and rural, wide-tailed, chaffinch, gray and black-fronted shrikes, oak-bearing grosbeak, field lark, gray crow, rook , jackdaw, magpie and many others. Thrush warbler is a typical inhabitant of reed thickets. Remez is a bird smaller than a sparrow, and the yellow-headed kinglet is the smallest of the birds of the Astrakhan region. From the order of storks in the region there are herons - gray, white - small and large, red, yellow, Egyptian, as well as spoonbill, loaf
a, large and small bittern, night heron. Of the anseriformes, we have a gray goose, swans - mute and whooper, mallard, gray duck, ruddy shelduck. teal crackling and many others. From the family of gulls, herring and black-headed gulls are common, as well as terns - small birds similar to gulls, but with a hookless beak and a forked tail. In the delta, there are black, white-winged and common terns. Of the owls in the lower reaches of the Volga, there is a gray owl, a short-eared owl, a little owl, an eagle owl, a splyuska and a long-eared owl. On the territory of the region you can also meet beautiful birds - the steppe eagle, goshawk, reed, steppe, field and marsh harriers, black kite, buzzard, saker falcon, hobby falcon, red falcon, common kestrel, osprey and a number of other species.

The total number of species of mammals living in our country does not exceed. From the order of rodents in the Astrakhan region there are ground squirrels - small and yellow, midday and comb gerbils. jerboas - terry-legged and imamranchik, field and house mice, mouse - baby, gray rat (pasyuk), common and water voles, muskrat, beaver, common mole voles, gray hamster and some other species. From the carnivorous order, the region is inhabited by wolves, common foxes, corsac foxes, raccoon dogs, steppe polecats, bandaging, ermine, weasels, badgers, otters and others. In recent years, in the lower reaches of the Volga, another species of predatory species has begun to occur - the American mink. This animal, which has valuable fur, was grown on our farms. Part of the animals escaped from the fur farm, multiplied, forming a fairly large natural population. The detachment of artiodactyls is represented on the territory of the region by wild boar, an inhabitant of reed thickets, saiga, an inhabitant of flat steppes and semi-deserts, and elk. A new species of ungulates has also been introduced - the red deer. Most of the domestic animals bred in the farms of the region also belong to the order of artiodactyls. The Astrakhan Territory is a region of developed sheep breeding, and the natural conditions of some regions of the region are favorable for breeding "ships of the desert" - camels. Bactrian camels of the Kalmyk (Astrakhan) breed are bred here. The order of pinnipeds includes only one species - the Caspian seal (nerpa). It is a marine mammal that gives birth on ice.

We also have muskrat, hedgehogs - eared and occasionally common, small and white-bellied shrews, which are insectivorous animals. These are very useful animals for humans, as they destroy a large number of harmful insects.

The Astrakhan region, due to its location in the Caspian lowland, has truly unique natural resources. The region is predominantly desert. There are also small forests, but they do not cover large areas. In the Astrakhan region there are protected areas, as well as Lake Baskunchak, known throughout the world for its unique composition.

The desert landscape of the area has created favorable conditions for the reproduction of representatives of the animal and plant world of certain species, which can not be found in every corner of the vast homeland.

The flora of the Astrakhan region

At first glance, it may seem that the flora of the Astrakhan region is very poor. In fact, it is. Not every plant will be able to adapt to a hot climate. Desert areas tend to be characterized by stunted vegetation accustomed to arid climates. The territory of the Astrakhan Territory is no exception in this regard. Here you can find varieties of wormwood, sedge, spurge and desert wheatgrass, etc.

The area in the Volga Delta has a higher percentage of air humidity, so the vegetation here is richer. The territory of this part of the region is no longer so deserted, the main part of the space is occupied by meadows. In addition, you can find small forests consisting of poplars, elms and willows. Other vegetation is also found, such as southern reed, coastal sedge, horned rock-foot and sorrel.

The main niche of the region's vegetation is occupied by agricultural crops. Fruits and vegetables that grow in the Astrakhan region serve as a source of vitamins not only for local residents, but also for nearby, and not only, cities of the country. People grow watermelons on melons, grapes, cherries and strawberries ripen in every garden. Apricots and apples here also do not surprise anyone.

Fauna of the Astrakhan region

The fauna of the Astrakhan region is incredibly diverse. Here you can meet a lot of such inhabitants of the land and the underwater world, which are far from everywhere. First of all, reservoirs contain not only a huge number of fish, but also hydras, several types of mollusks and a variety of worms. Fish species include herring, sturgeon breeds, gobies, salmon, buttonheads and white salmon.

The richest and most diverse fauna of the Volga delta. There are almost five thousand arthropods here, including a huge number of beetles, butterflies, bugs, homoptera or hymenoptera. There are a huge number of spiders in the Astrakhan Territory, and some of them are dangerous to human life, for example, karakurt or South Russian tarantula.

Surrounded by ponds, you can meet frogs or turtles. In desert areas, you can occasionally stumble upon snakes. Among the harmless representatives, the snake is widespread, and among the poisonous ones, the viper and muzzle. Passerines, gray herons, white-tailed birds, swans, gray geese, etc. predominate among the birds.

Typical representatives of mammals in the Astrakhan region include saiga, fox, wild boar, and American mink. You can also meet wolves, ground squirrels, otters or European roe deer.

The climate of the Astrakhan region

Climatic conditions of the Astrakhan region are moderately continental. It is located in an arid zone, which is manifested by warm winters and hot summers. On the territory of the Astrakhan region, there is a choice of air masses in several directions, namely, from the Mediterranean, the Atlantic and Kazakhstan.

The air of the region is quite dry, it is especially pronounced in the summer. The reason for this is the influence of the east winds. Precipitation in this area is quite rare. In winter, it often rains, snow is an extremely rare occurrence, if it falls, it quickly melts. Precipitation is very rare in summer.

The landscape structure of the region is represented by 8 landscapes.

The Volga-Sarpinsky and Baskunchak landscapes were formed in the semi-desert zone.

The desert zone is represented by the Volga-Ural, Volga-Priergeninsky, Western and Eastern ilmen-bump landscapes. Intrazonal landscapes include the Volga-Akhtuba floodplain and the delta of the Volga River. In each landscape, several areas are distinguished with a set of tracts characteristic of them.

COURTS IN THE VOLGA DELTA - RINGS

According to the soil-geographical zoning of Russia, the territory of the Astrakhan region is assigned to the Caspian province of light chestnut and brown semi-desert soils, solonchak complexes, sandy massifs and solonchak spots.

The surface waters of the Astrakhan region are represented by the Volga River with numerous watercourses (about 900 units), fresh and salt water bodies (about 1000 units) and the largest enclosed body of water on the planet - the Caspian Sea.

NATURAL RESOURCES

natural gas, salt, gypsum. Oil reserves can be estimated at about 300 million tons, the depth of occurrence is from 2 to 5 km.

In the 1950s, the Promyslovye gas field was discovered, which marked the beginning of the gasification of Astrakhan and a number of villages.

In August 1976, the Astrakhan sulfur and gas condensate field was discovered. It is located 70 km northeast of Astrakhan, its area is 2500 square km.

The modern network of protected areas in the region, including state reserves, hunting grounds and state natural monuments, was formed in the 70s-80s of the XX century. Currently, the network of specially protected natural areas (PAs) of the Astrakhan region consists of 2 state nature reserves, 3 biological reserves and 35 natural monuments.

State natural and biological reserves

Name of the reserve Year of organization Area,

Bogdinsko-Baskunchaksky 1993 35.2 landscape

Ilmenno-Bugrovoy 1995 6.9 landscape

Burghley Sands 1998 3.1 Landscape

Stepnoy 2000 87 landscape

Teplushki 2000 4.7 biological

Boar 2001 2.1 biological

Enotaevsky 2001 3.8 biological

DIGGINGS IN THE ASTRAKHAN REGION

LANDSCAPES AND NATURAL AREAS

The main landscape of the region is represented by a gently undulating desert plain complicated by huge massifs of mounds, sands, dry hollows, lakes, karst landforms, etc.
The modern absolute mark of the Caspian Sea is located at a level of 27 m below the level of the World Ocean. To the north, the absolute elevations of the surface increase and in the northernmost part of the region reach plus 15 - 20 m. The highest point is Mount Big Bogdo - 161.9 m, located in the northeast of the region.
The region is assigned to the second time zone, like Moscow, although local time in Astrakhan is ahead of Moscow by 42 minutes.
The region belongs to the Volga region, the Southern Federal District. The geographical position of the Astrakhan region is peculiar. It is located on the border of Europe and Asia, the Volga gives access to 5 seas.

The climate of the Astrakhan region

The first observations of the weather in Astrakhan began in 1745 by individual enthusiasts - Astrakhan. In 1888, a weather station was opened, which was further developed and improved. In 1988, it was renamed the Regional Center for Hydrometeorology and Environmental Monitoring. The weather in the region is systematically monitored at seven meteorological stations: in Astrakhan, Upper Baskunchak, Dosanga, Zelenga, Liman, Kharabali, Cherny Yar.
Our region occupies almost the middle position between the equator and the North Pole. The longest day in our region: in the south its duration is 15 hours 42 minutes, in the north 16 hours 09 minutes. In winter, the shortest day in the region is December 22, its duration is 8 hours 42 minutes in the south, 8 hours 18 minutes in the north.

The duration of the period with temperatures above 0°C is 235-260 days.

The flatness of the relief to the north of the Astrakhan region contributes to the unimpeded passage of cold arctic masses, which are associated with a decrease in temperature at any time of the year.
The underlying surface is an important climate-forming factor. The main background of the region is a plain, sometimes with sandy massifs. The exception is the Volga-Akhtuba floodplain and the Volga delta with a large amount of water surface, meadow vegetation and ribbon forests. The climate here has its own specific features: throughout the year, the air temperature at night is higher than in the surrounding desert areas, and in summer it is 2-4 ° C cooler than outside this territory.

The climate of the Astrakhan region is temperate, sharply continental - with high temperatures in summer, low temperatures in winter, large annual and summer daily air temperature amplitudes, low precipitation and high evaporation.
The average annual air temperature varies from south to north from 10°С to 8°С. The coldest month is January, the average temperature drops to minus 5-9°C. The highest average temperature of 24-25°C is observed in July. The amplitude of the coldest and warmest months is 29 - 34°C, which indicates a high continental climate.

The annual amount of precipitation ranges from 180-200 mm in the south to 280-290 mm in the north. The main amount of precipitation (70-75%) falls during the warm season. In winter, precipitation falls in the form of snow, sleet, and rain. Often they are of a concise nature. In summer, heavy rains are accompanied by thunderstorms, sometimes with hail. The normal average annual air pressure in the Astrakhan region at 0°C is 165 mm. rt. Art., in the cold period increases to 770, in the warm period it decreases to 760.
East, southeast and northeast winds are typical for our region. In summer they determine high temperatures, dryness and dustiness of the air, in winter - cold and clear weather. Dry winds are associated with these winds from April to August. Winds from other directions bring cloudiness and precipitation. During the year, winds with a speed of 4-8 m/s prevail, but in some cases the speed increases to 12-20 m/s or more. The greatest number of days without wind is observed in summer. Local winds form in our area. In summer, weak breezes blow on the shores of the Caspian Sea: during the day - on land, at night - towards the sea. In winter, the northern part of the Caspian freezes and breezes do not form. Winds blowing continuously for several days from the Caspian side raise the water level on the sea coast and in the Volga delta. Astrakhans call them sailors.

The actual climatic seasons in the region do not coincide with the calendar ones. The criterion for the selection of seasons are the dates of stable transitions of air through certain limits.

A unique protected area of our country.

How our children see it depends on each of us. We are responsible for every action before our children! Children are our future. Often people behave like uninvited guests. Mountains of garbage, broken glass, broken and burned trees - that's what remains in the place of the so-called rest. Our children see all this, and it seems to them absolutely normal, because the authority of an adult is unshakable for a child.

Although these are common truths, and many will say - yes, we all know! Not enough morals! - think about the fact that a few years ago the Lower Volga in the Kharabal region was a true Mecca of anglers. Now Akhtuba is far from the same fishing! Many people remember and know the branch of Akhtuba - Ashuluk, where twenty years ago the fish teemed with swarms - I was there last year: a sad sight. Therefore, I decided to touch on the topic of respect for nature, as well as some moral aspects of human behavior on fishing.

Where to go fishing, in order to also have a great rest, swim, enjoy first-class fish dishes, fresh fruits and the gentle sun? Of course, in the Astrakhan region. Fishing in the Astrakhan region is the main dream of every true fisherman's life. Fishing in Astrakhan is a great opportunity to improve your professional level as a fisherman. In this part of Russia there are no seasonal restrictions on biting.

At any time of the year, fishing will be successful and will delight you with a fabulous catch. In summer, you can relax in the Volga Delta no worse than on the sea coast. And the ecological cleanliness and amazing nature of the Astrakhan region will make you choose this type of holiday again and again.
Fishing in the Astrakhan region is a rare opportunity to relax with the whole family. Where else can you teach a child the basics of fishing, providing him with a good rest in the purest natural conditions? Probably nowhere. Fishing in the Astrakhan region in the spring will please you both with catching carp, preparing for spawning, and catfish, waking up after hibernation. Starting from spring and ending in late autumn, zander and asp are perfectly caught.

From the beginning of April to the last weeks of May, large bream is perfectly caught, and in mid-April, when the vobla spawns, you can enjoy a rich catch of this fish. Winter fishing is not far behind. A specialist will tell you a good place for winter fishing, and you are guaranteed a rich catch combined with a healthy holiday. There are practically no failures in fishing at fishing bases in the Volga delta, neither among professionals, nor among those who come to fish for the first time.

There is such a large abundance of fish that everyone is always lucky. The Volga Delta is inhabited by more than 120 species of fish. Among them: catfish, asp, pike perch, pike, bream, carp, crucian carp, rudd, roach, vobla, blue bream, silver bream, tench, sabrefish, silver carp, sturgeon, beluga, stellate sturgeon and others. The fishing season begins in the first days of April, when the famous Volga roach is pre-spawning.

They catch it on a worm, maggot and corn with fishing rods or a donkey. Together with vobla they take silver bream, bream, rudd, crucian carp and carp. Spinners at this time are hunting for a large asp, a catfish that has just emerged from a winter stupor, a thick roe perch. At the very edge of the reed stands a pike, heavy before spawning.
The best time to hunt big catfish is spring (April) and autumn (October - November). In summer, catfish and catfish weighing up to 10-15 kg predominate in catches.

Catfish sometimes reach a weight of more than 100 kg. A mustachioed giant can ride a boat along the reach for hours and, as a result, still overcome the tackle - unbend the hook, break the clasp, or simply go into snags and cut off the strongest fishing line. Autumn carp is a serious adversary. The fish rushes like a wild horse, resists to the end, delivering an amazing experience to the angler. The most frisky fighters are carp weighing 10-12 kg. The larger ones are lazy and resist sluggishly.

Such a quantity of pike, as on the Caspian peals, is nowhere to be found. Sometimes it seems that there are more fish than water. Our fishermen without leaving one point catch about 70 pieces in 2 hours. Fish weight from 1 to 6.5 kg! After the end of spawning, the pike begins to be actively caught by spinning in the same areas. She takes on almost any bait, but best of all - on "rotators" and floating wobblers.

Mostly milk jugs come across, weighing about 2 kg. (apparently, they tolerate spawning more easily than female eggs). Asp in the delta is caught throughout the open water season, and only at the height of the summer heat, in July, the bite is very sluggish. And yet, from the rest of the period, when it comes to catching trophy asp, April and October can be distinguished. It is during these months that there is every chance to catch the largest and strongest Volga asp.
AKHTUBA

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SOURCE OF INFORMATION AND PHOTO:
Team Nomads
http://www.geografia.ru/
Astrakhan region - official site
http://geo.astrakhan.ws/
textbook of geography of the Russian Federation.
Resources of surface waters of the USSR: Hydrological knowledge. T. 3. Northern Territory / Ed. N. M. Lived. - L .: Gidrometeoizdat, 1965. - 612 p.
Wikipedia site.
Water register of the Russian Federation.
http://www.photosight.ru/

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