Caspian lowland population. Caspian lowland on the map
The northern coast of the Caspian Sea is occupied by the Caspian lowland, part of it is located on the territory of Kazakhstan. The northern border of this area is the General Syrt, the Volga Upland is bordered by the west, the eastern border is the Cis-Ural plateau and the Ustyurt plateau. The area of \u200b\u200bthe territory is approximately 200 thousand square meters. km.
The lowland reaches its maximum height in the north - it is up to 100 m above sea level, in the south this figure drops to 28 m below sea level. The geological basis of the Caspian lowland consists of rocks of the late Quaternary age. This region is crossed by several large rivers: Volga, Ural, Terek, Kuma. But there is no permanent hydrographic network in the region - in the summer small rivers dry up. Some of it forms hollows that create lacustrine floods. Kamysh-Samara lakes and Sarpinsky lakes are examples of such reservoirs. On the territory of the lowland there are salt lakes, for example, Baskunchak and Elton. Lake Elton is considered one of the saltiest lakes in the world.
Volga, the most large river, flowing into the Caspian Sea, lies in the west of the Caspian Lowland, its source is located north of Astrakhan. The width of the main branches of the river is 300-600 m. The Volga branches into many channels and eriks. In Europe, the Volga has the largest delta - the river is divided into 800 estuaries.
The climate of the Caspian lowland is sharply continental. In the north of the region in January average temperature reaches -14 degrees, on the coast it fluctuates around -8 degrees. In July, the average temperature in the northern region is +22 degrees, in the south it rises to +24 degrees. Dry winds often occur in the region. The reason for this is the rapid evaporation of the water. The precipitation is not enough to moisten the soil well; the uneven amount of precipitation in the regions also contributes to the dry wind. In the southeast of the Caspian Lowland, precipitation is less than 200 mm, but in the northwest it is almost twice as large.
The flora of the steppes and semi-deserts is characteristic of the Caspian lowland. From north to south, the feather-grass-forb steppe is replaced by feather-grass-fescue, the wormwood-cereal semi-desert becomes the final point of flora change. Large estuaries are covered with thickets of wheatgrass - a representative of meadow grasses. In desert areas, the amount of vegetation is decreasing.
A significant part of the region's vegetation is used as pastures for livestock. Volga-Akhtubinskaya floodplain is the main agricultural region. They are engaged in gardening, melon growing and vegetable growing.
Salt lakes of the Caspian lowland are the place where table salt is mined. Oil and gas are being developed on the territory of the Ural-Emba region.
Fauna of the Caspian Lowland
The Volga-Ural interfluve, located on the coast of the Caspian Sea, has the best pastures. The area is well developed for hunting and fish farming. The Ural-Emba interfluve in the country is known for its rich oil and gas deposits.
The Caspian lowland is a habitat for fifty species of mammals, three hundred species of birds, twenty species of reptiles and amphibians. For migratory and wintering birds, the coast of the Caspian Sea is of great importance. According to biologists' calculations, about 1.5 million waterfowl winter in the southern Caspian.
On the coasts of the north and north-east of the Caspian Sea, there is a migration area for 3 million waders. In summer, half a thousand pairs of gray geese, 2 thousand pairs of ducks and 2.5 thousand pairs of mute swans settle in the reeds. There are also nesting grounds for gulls, terns and pink pelicans in this area.
Saigas are commercial ungulate mammals that live in the Volga-Ural interfluve. In the early 2000s, this species was threatened with extinction, so a ban on shooting saigas was introduced in order to restore the population of these animals. It is noteworthy that tracking the state of the abundance of this species is complicated by the constant migrations of saigas across different territories.
In the Caspian lowland, animals such as foxes, wolves and steppe ferrets are numerous. In the anthropogenic desert, called the Black Lands, there is a reserve of the same name, which studies the landscapes of the steppe, semi-desert and desert.
The region is home to several critically endangered endemics. These animals include:
1. Long-spined hedgehog. An insectivorous animal with a small body weight (up to 750 g), leading a nocturnal lifestyle. This species is protected in the reserves of Kazakhstan, Uzbekistan and Turkmenistan.
2. The Turkmen mountain sheep (Ustyurt mouflon) is an artiodactyl mammal of the bovid family. Listed in the Red Book of Kazakhstan.
3. Honey badger, a weasel predator. On the territory of the Caspian region, it is distributed on the border with the Ustyurt plateau.
4. Caspian seal (Caspian seal), a representative of the family of true seals, which are distributed over the coastal area of \u200b\u200bthe entire Caspian Sea. In winter, these animals migrate to the northern coast, forming colonies. These animals are listed in the Red Book as a species that is threatened with complete extinction.
5. Bobrinsky's leather - small bat, whose habitat is the deserts of Kazakhstan.
Representatives of small rodents - jerboas and gerbils - also have a low level of abundance and density. There are up to 6 individuals per hectare. There are two times less gophers.
Valuable fur animals and other commercial species play an important role in the region's economy. Small rodents distribute plant seeds, while they are prey for predators. Due to the fact that rodents are carriers of various infections at the same time, there is a natural control of the number of predators.
Environmental problems of the territory
The rise in the level of the Caspian Sea has led to the emergence of a number of problems - flooding of large areas of lowland, flooding of ports, settlements, transport facilities, etc. An anthropogenic factor plays a significant role in the environmental problems of the region. Vigorous human activity contributed to the pollution of rivers and saturation environment waste from large industries. Improper and overuse of land has accelerated the development of soil erosion.
On the territory of Kalmykia, oversaturated with pastures, unsystematic cattle grazing has led to desertification of the area. To avoid the aggravation of this environmental problem, a number of measures were taken to prevent desertification. In particular, the “Federal Program to Combat Desertification of the Territory” was introduced in the republic, with the help of which they were able to achieve their first successes.
Water pollution of the Volga River, which flows into the Caspian Sea, is another environmental issue region. Since this river flows through the entire Russian Plain, all waste from enterprises located along its entire length gets into its water. As a result, the polluted waters of the Volga led to a reduction in species diversity and the spread of alien bacteria in the Caspian Sea.
Oil, which is the main pollutant, inhibits the development of phytoplankton and phytobenthos of the Caspian. Oil pollution interferes with normal heat and gas exchange, water begins to evaporate more slowly. On fish, shellfish and others marine life negatively affected by alien organisms arriving from sea transport. So, the settlement of the ctenophore Mnemiopsis in the waters of the Caspian Sea, which had managed to empty the waters of the Azov and Black Seas, was a real disaster. Reproducing rapidly and uncontrollably, the comb jelly destroys the stocks of zooplankton that the Caspian fish feed on. The disruption to the food chain has led to a decline in the indigenous population of the Caspian Sea.
Oil pollution negatively affects waterfowl as well. Their plumage loses its heat-insulating and water-repellent properties, for this reason many birds die. Oil spills lead to a decrease in the number of other animals in the region.
The construction of hydroelectric power plants on rivers leads to silting of the channel. The number of fish in the waters is decreasing due to the fact that the natural habitat of the fish is undergoing drastic changes. Zones of nature reserves located in the north of the Caspian lowland regulate geophysical work, which contributes to the conservation of species diversity.
Environmental problems can be mitigated or even completely eliminated by investing impressive sums of money. Unfortunately, most enterprises, in pursuit of their own profit, are rather dismissive of environmental protection. The Caspian Sea and its coastal areas continue to get polluted.
14.07.2019 19:12
Famous nature reserve "Black Lands", created where practically no people live and there is no water, is located in the Caspian lowland, an interesting object from the point of view of science and geotourism. The Caspian lowland is a territory located at the extreme point of the southeast of the Russian plain and enveloping the Caspian Sea. In the southeast, black lands or Khar-Gazr in Kalmyk, approaches the Volga delta, it is here that another interesting natural object - Baer hillocks (in honor of academician K.M.Berr, who discovered this miracle of nature), which are sandy ridges up to 45 meters high and up to 300 meters wide, the length of which is several kilometers. Between the hillocks you can see the ilmens, small lakes overgrown with grass, any activity is prohibited here, since it can destroy these delightful creations of nature.
On the territory of the Caspian lowland, the Volga-Akhtubinskaya floodplain is located, where the Great Russian River is divided into many branches, there are about 800 of them, flows into the Caspian Sea and ends its course. On this territory, the eponymous natural Park, with the aim of protecting the ecosystem and nests of more than 200 species of birds. This place is extremely popular among fishermen, because the variety and size of underwater inhabitants can surprise even the most seasoned fisherman! Therefore, when traveling in the Volga delta, you should definitely take a selfie with a huge catch, especially since fishing promotions in July will significantly save on this type of vacation. Another natural wonder located in the Caspian lowland can be safely called the famous salt lake Baskunchak, which is rightfully considered a bottomless bowl full of salt. In addition to the above-mentioned sights created by nature, it is also worth noting: the lotus valley, the Burly sands reserve, the Kordon tract, Manych - Gudilo - a nature reserve and, of course, the Big Bogdo salt dome.
In addition to natural attractions, the region is rich in historical ones. Among the architectural monuments it is worth noting such as - Devil's settlement, located in the Ikryaninsky district, erected during the Golden Horde, Saray-Batu or as it is also called the Selitrennoe gordishche, is a fortified complex built around the beginning of the 13th century. It is also worth noting the burials discovered here, dating back to the Bronze Age and later monuments, such as the Khoscheut khurul, a monument to the wars that defeated Napoleon. Also, on the territory of cities located in the Caspian lowland, there are many cultural and religious buildings built in different eras.
The most big city located here is Astrakhan, the center of the region of the same name, most of the enterprises engaged in the extraction and processing of minerals, which are rich in the lowland territory, are concentrated here. And here - oil, uranium, gas, many industrial and precious metals are extracted.
Part of the Caspian lowland is located on the territory of Kazakhstan, here the largest regional center is the city of Atyrau, which is considered the oil capital of all Kazakhstan.
The Caspian lowland is not only the "Black Earth" where nothing but wormwood grows, but also the most fertile lands of the Astrakhan region, where the climate allows growing some of the most delicious watermelons. The list of attractions in the region is not limited to the above list, to describe all of them not even ten such articles are enough, such a volume of printed information is unlikely to be adequately assimilated, therefore, if you are interested, we advise you to visit this unique place located on the territory of our Motherland. Good luck.
The Caspian lowland is located in Eurasia. This is the southern tip of the East European Plain, adjacent to the Caspian Sea in its northern part. Natural boundaries: from the north - the General Syrt upland, west - the Volga, Stavropol uplands and Ergeni, east - the Ural plateau and Ustyurt, from the south - the Caspian Sea. Located on the territory of Russia and Kazakhstan.
Coordinates:
Latitude: 47 ° 32 "N
Longitude: 49 ° 01 "E
The Caspian Lowland is a huge plain with an area of \u200b\u200b200,000 square kilometers, from the south sinking below sea level. These are steppes, deserts, semi-deserts and salt marshes, although many rivers flow there, including large ones: the Volga, at the confluence of the Caspian Sea, forming a vast delta, and the Urals. Emba, Terek, Kuma cross the lowland. There are a lot of salt lakes - Baskunchak, Inder, Aralsor, Kamys-Samara lakes, Elton, Botkul.
Among the flat as a pancake, here and there are domes of salt, called mountains. Bolshoy Bogdo is a 150-meter high salt mountain, is a cult place of Buddhists. The main part of the lowland is steppes and sands used for pastures. In the Volga-Ural interfluve, fishing and hunting are developed, the famous Astrakhan watermelons grow in the Volga floodplain. There are oil and gas fields in the Ural-Emba interfluve.
In the Caspian lowland, despite the seeming stinginess of nature, there are many natural attractions. There are archaeological, historical, cultural different nations and eras.
Russia
Reserves "Bogodino-Baskunchaksky", "Astrakhansky", "Black Lands". Volgo-Akhtubinskaya Poima is a natural park. Zakazniks "Manych-Gudilo" and "Sands Burly", Mount Bolshoye Bogdo, Valley of Lotus, Kumo-Manychskaya depression (divides Eurasia), Kordon tract, Baer hillocks. Archaeological monuments: Devil's settlement of the Golden Horde era (Astrakhan region), Saray-Batu (Astrakhan region), burials in Turtles of the Bronze Age, Samosdelka settlement (Astrakhan region). Among the cultural objects, one can note the Khosheutovsky khurul (a Kalmyk monument in honor of the victory over Napoleon in the village of Rechnoye, Astrakhan region), the watermelon museum (the city of Kamyzyak).
Kazakhstan
Ustyurt reserve, Karagiye depression on the Mangyshlak peninsula, Lake Shalkar (Aktobe region), floodplain forests of the Ural river with unique and relict vegetation, Sanal and Sazanbai canyons. The resort town of Aktau and the Kenderli complex are located on the Caspian coast. You can travel along the Great Silk Road, which passed through these places. There are many archaeological sites: Kyzyl-Kala (red fortress), the city of Sary-Aychik - the Golden Horde center of trade. The sacred places of Muslims are the underground mosques Shopan-Ata and Beket-Ata.
The famous reserve "Black Lands", created where practically no people live, and there is no water, is located in the Caspian lowland, an interesting object from the point of view of science and geotourism. The Caspian lowland is a territory located at the extreme point of the southeast of the Russian plain and enveloping the Caspian Sea. In the southeast, black lands or Khar-Gazr in Kalmyk, it approaches the Volga delta, it is here that another interesting natural object is located - the Berovskiye hillocks (in honor of ak.
Where is the Caspian lowland on the physical map?
K.M. Barr, who discovered this miracle of nature), which are sand ridges up to 45 meters high and up to 300 meters wide, which are several kilometers long. Between the hillocks you can see the ilmens, small lakes overgrown with grass, any activity is prohibited here, since it can destroy these delightful creations of nature.
On the territory of the Caspian lowland, the Volga-Akhtubinskaya floodplain is located, where the Great Russian River is divided into many branches, there are about 800 of them, flows into the Caspian Sea and ends its course. On this territory, a natural park of the same name has been established with the aim of protecting the ecosystem and nests of more than 200 species of birds. This place is extremely popular among fishermen, because the variety and size of underwater inhabitants can surprise even the most seasoned fisherman! Therefore, when traveling in the Volga delta, you should definitely take a selfie with a huge catch, especially since fishing promotions in July will significantly save on this type of vacation. Another natural wonder located in the Caspian lowland can be safely called the famous salt lake Baskunchak, which is rightfully considered a bottomless bowl full of salt. In addition to the above-mentioned attractions created by nature, one should also note: the lotus valley, the Burly sands reserve, the Kordon tract, Manych - Gudilo - a nature reserve and, of course, the Big Bogdo salt dome.
In addition to natural attractions, the region is rich in historical ones. Among the architectural monuments it is worth noting such as - Devil's settlement, located in the Ikryaninsky district, erected during the Golden Horde, Saray-Batu or as it is also called the Selitrennoe gordishche, is a fortified complex built around the beginning of the 13th century. It is also worth noting the burials discovered here, dating back to the Bronze Age and later monuments, such as the Khoscheut khurul, a monument to the wars that defeated Napoleon. Also, on the territory of cities located in the Caspian lowland, there are many cultural and religious buildings built in different eras.
The largest city located here is Astrakhan, the center of the region of the same name, most of the enterprises engaged in the extraction and processing of minerals, which are rich in the lowland territory, are concentrated here. And here - oil, uranium, gas, many industrial and precious metals are extracted.
Part of the Caspian lowland is located on the territory of Kazakhstan, here the largest regional center is the city of Atyrau, which is considered the oil capital of all Kazakhstan.
The Caspian lowland is not only the "Black Earth" where nothing but wormwood grows, but also the most fertile lands of the Astrakhan region, where the climate allows growing some of the most delicious watermelons. The list of attractions in the region is not limited to the above list, to describe all of them not even ten such articles are enough, such a volume of printed information is unlikely to be adequately assimilated, therefore, if you are interested, we advise you to visit this unique place located on the territory of our Motherland. Good luck.
Tags: travel russia
The relief of the Saratov region is diverse, in one article we cannot show you how different it is from each other in different parts of the region, so we will write about each type of relief separately. In this article, you will learn everything about the Caspian lowland, including its geological structure and hydrography. Read an article about the geological structure of the Saratov region in our article: Geological structure of the Saratov region.
Caspian lowland is located in the basin of the lower reaches of the Bolshoi and Maly Uzeni rivers and occupies the southeastern part of the Saratov region.
Caspian lowland: description and features
Geologically, this lowland is the youngest - it is a marine accumulative plain of the early Khvalynian age. Its surface is even, slightly hilly and slightly divided. Absolute marks: in the north - from 45-50 m, in the south - 20-25 m. Flat inexpressive watersheds up to 50 m high are composed of sea sand, sandy loam and "chocolate" clays of the Early Khvalyn age, lying almost horizontally.
On its surface there are many estuaries, as well as small "steppe saucers" (depressions) with a diameter of 1.5-2 m. Some estuaries, due to the accumulation of melt water, form lakes and swampy areas.
The relief of the region's territory is characterized by the modern movement of the earth's crust. It is accompanied by intensification of erosion processes (the growth of ravines, landslides, craters, etc.), and relief leveling. Also read our article about the relief of the Saratov region.
The lowland, located to the north of the Syrtovaya Plain, is separated by a well-defined abrasion pre-syrt scarp in the relief, which has the form of a straight slope 50-80 m wide, less often 20 m. The surface of the plain has a slight slope to the south and southeast.
Estuaries are widespread, suffoeionic depressions, saucer-shaped depressions, mounds of biogenic origin, coastal ramparts, lakes, differing in shape, size, and duration of the water stand. The river and ravine-gully network on it is poorly developed. The lowland is composed of clays, loams, and sands. The depth of the incision of the valleys does not exceed 2-5 m. Erosion gives way to accumulation.
The Caspian lowland in the Quaternary period was the arena of several Caspian transgressions. The largest of them was the early Khvali, when the sea covered the entire lowland. The boundary of this transgression in the north is clearly marked by an abrasion scarp. Since then, erosion and other processes have little changed the original appearance of the sea plain.
The Caspian lowland is confined to the Caspian syneclise and is currently an area of \u200b\u200bsubsidence and accumulation of a thick (up to 17 km) cover of sedimentary deposits. Against the background of general immersion, there are areas of intense uplift in places where salt domes and massifs develop.
When writing the article, the following sources were used: Geography of the Saratov Region. Saratov, 1997, sargidro.narod.ru; Photo: 5klass.net
Sights of Russia: Caspian lowland
Abstract on the topic:
Caspian lowland
Plan:
- Introduction
- 1Geographic location
- 2Geological structure
- 3Climate and vegetation
- 4 Economic value
- 5Source
Introduction
Caspian lowlands- lowland located on the East European Plain, surrounding the northern part of the Caspian Sea.
1. Geographical location
The Caspian lowland is bordered in the north by the General Syrt, in the west by the Volga Upland and Ergeni, in the east by the Ural Plateau and Ustyurt. The lowland area is about 200 thousand km². Height above sea level up to 149m, southern part lowland lies below sea level (up to -28m).
The Caspian lowland is a flat surface, gently sloping towards the sea, among which individual heights rise - the Inder Mountains, Big Bogdo, Small Bogdo and others.
The Caspian lowland is crossed by the rivers Ural, Volga, Terek, Kuma and others. Small rivers (Big and Small Uzen, Uil, Sagiz) dry up in summer or break up into a number of basins, forming lake floods - Kamysh-Samara lakes, Sarpinsky lakes. There are many salt lakes (Baskunchak, Elton, etc.).
2. Geological structure
The Caspian lowland includes several large tectonic structures (Caspian syneclise, Ergeninskoe uplift, Nogai and Terskaya depressions). In the Quaternary, the lowland was repeatedly flooded with the sea, which left clay and loamy in the northern part, and sandy deposits in the southern part.
The surface of the Caspian lowland is characterized by micro- and meso-forms in the form of depressions, estuaries, spits, hollows, in the south by eolian forms, and along the coast of the Caspian Sea by a strip of the Baer hillocks.
3. Climate and vegetation
The climate is sharply continental. Average January temperatures are from −14 ° in the north to −8 ° on the coast, in July, respectively, + 22 °, + 23 °. Precipitation is from 200-150mm in the southeast to 350mm in the northwest, evaporation is about 1000mm. Dry winds are frequent.
The soils and vegetation of the Caspian lowland are characterized by great complexity. Salt licks and salt marshes are not uncommon.
In the north, there are wormwood-grass steppes on light chestnut soils, in the south there are semi-desert and desert on brown and sandy soils with a predominance of wormwood.
4.
Caspian Lowland Map
Economic significance
Used as a pasture.
In the Volga-Akhtubinskaya floodplain melon growing, horticulture and vegetable growing are widespread.
Oil and gas production (Caspian oil and gas province), in the lakes - salt production (lakes Baskunchak, Elton, etc.).
5. Source
A.A. Grigoriev Brief Geographical Encyclopedia. Volume 3. - M .: Soviet encyclopedia, 1962. - P.580.
Satellite photo of the lower part of the Volga, the Caspian lowland and the northern part of the Caspian Sea
Caspian lowlands- lowland surrounding the northern part of the Caspian Sea.
Geographical position
The Caspian lowland is bordered in the north by the General Syrt, in the west by the Volga Upland and Yergeny, in the east by the Ural and Ustyurt plateaus. The area is about 200 thousand km². Height up to 149m, the southern part of the lowland lies below ocean level and is -28m.
The Caspian lowland is crossed by the rivers Ural, Volga, Terek, Kuma; small rivers (B. and M. Uzen, Uil, Sagiz) dry up in the summer or break up into a series of depressions, forming lake floods - Kamysh-Samara lakes, Sarpinskie lakes. There are many salt lakes (Baskunchak, Elton, etc.).
The Caspian lowland is a flat surface, gently sloping towards the sea, among which individual hills rise - Inderskpe mountains, Big Bogdo, Small Bogdo and others.
Map on Google.Earth
Geological structure
The Caspian lowland includes several large tectonic structures (Caspian syneclise, Ergeninskoe uplift, Nogai and Terskaya depressions). In the Quaternary, it was repeatedly flooded by the sea, which left clay and loamy in the northern part, and sandy deposits in the southern part.
The surface of the Caspian Lowland is characterized by micro- and meso-forms in the form of depressions, estuaries, spits, hollows, in the south by eolian forms, and along the coast of the Caspian Sea by a strip of Baer hillocks.
Climatic conditions
The climate is dry and continental.
Caspian lowland
Average temperatures in January are from -14 ° in the north to -8 ° on the coast, in July, respectively, + 22 °, + 23 °. Precipitation ranges from 200-150mm in the south-east to 350 mm in the north-west, evaporation is about 1000mm. Dry winds are frequent.
The soils and vegetation of the Caspian lowland are characterized by great complexity. The soils are light chestnut, solonetzic, there are solonetzes and saline soils. In the north, wormwood-cereal vegetation, in the south, the amount of cereals decreases, wormwood begins to prevail. Used as a pasture. In the Volga-Akhtubinskaya floodplain melon growing, gardening, vegetable growing. Deposits of oil (Embensky oil region), in the lakes - table salt (lakes Baskunchak, Elton, etc.).
A source
A.A. Grigoriev Volume 3 // Brief geographical encyclopedia... - M .: Soviet encyclopedia, 1962. - S. 580 p.
§ 24. Plains (textbook)
§ 24. Plains
1. Remember how the plains are represented on the map.
2. What landforms are common in your area?
Surface flatFlat relief prevails on our planet. This is clearly visible on the physical map of the hemispheres.
The plains are flat. The surface is smooth, there are no noticeable ups and downs on it. there is hilly plainsWhere rises alternate with declines. However, such inequalities have a relative height of no more than 200 m. Consequently, plains - These are relatively flat areas of the earth's surface with small fluctuations in height. Most of the plains of the world are huge in size. This is reflected in their names: Great Plain of Chinain Eurasia, Great plains in North America... On one Eastern European Plain fit the territories of many states - Ukraine, Belarus, Moldova, Lithuania, Latvia, Estonia and Russia (western part).
Height flatAccording to the height above sea level among the plains, there are low (lowlands), elevated (hills) and high (Plateau).
Lowlands have absolute heights up to 200 m.
For example, West Siberian Plain with a flat surface in Eurasia. On the earth's surface are lowlands located even below sea level. For example, Caspian lowland lies 28 m below sea level.
Hills - These are plains with absolute heights from 200 to 500 m. Uplands include, for example Podolskin Ukraine.
Plateau - They are also flat, only high enough - more than 500 m above sea level. Examples are Central Siberian plateau and plateaus Dean in Asia.
The flat relief of Ukraine is created by the alternation of lowlands and uplands. By the physical cartel it is easy to determine where they are located: the yellowish color of the hills differs from the number of green, indicating the lowlands. So, Pridneprovskayaelevationlocated in the western part, and Black Sea lowland lies in the south of the country. However, in nature it is difficult to notice the transition from one type of plain to another. If you go, for example, from Odessa to Vinnitsa, then the terrain will gradually rise and the traveler, unnoticed for himself, continues his journey with a non-change, but with a hill. The change in absolute heights can only be set using special devices.
Plain educationPlains can form as a result of the rise and release of sea water. This is observed with vertical movements of the earth's crust. Such plains are called primary... For example, Prichernomorskayalowlandwas once a part of the Black Sea bottom.
Secondaryplainsare formed in different ways. Some of them, created by river deposits (sands, loams), accumulated for a long time in the depressions of the earth's crust. Their surface is flat or slightly wavy. Mesopotamian lowland formed by the deposits of the Tigris and Euphrates rivers. Plains can also arise in place of mountains, when, under the influence of external processes, their tops and slopes are destroyed, and the basins are filled with debris. Then the mountainous area gradually flattens out and turns into a hilly plain. Kazakh melkosopochnik- High plain, among which some remnants of mountain ranges rise. In Ukraine, such a plain is Donetsk ridge.
Plains are usually covered with sedimentary rocks: sand, clay, forests, gravel, limestone. Igneous and metamorphic rocks, granites and gneisses, lie deep beneath them. In some places, they come to the surface. The sedimentary layers are horizontal or with a slight slope. It is possible to determine in which direction the slope of the plain both on the ground and on the map is in the direction of the river flow.
Changing the surface of the plains.Plains change under the influence of internal and external processes. Plains, as a rule, lie on platforms - ancient flattened stable areas of lithospheric plates. therefore internal processes appear there mainly in slow vertical movements.
External processes are associated with the work of water and wind. Where there are enough flowing waters, river valleys and ravines are formed. Ravines destroy areas of fertile land. To combat them, people plant bushes and trees. In deserts, where it is dry, the surface of the plains changes due to weathering, as well as the action of wind, which creates sand ridges, dunes and dunes. Now a significant outside force became and economic activityhuman. During the construction of cities, the laying of roads, the ravines are covered up, they create fill. During the extraction of minerals, quarries arise, and hills with waste rock grow near the mines - waste heapsUnfortunately, often the transformation of the natural surface by man has negative consequences. Careless economic activity can lead to the emergence of a dense network of ravines, the transformation of fertile land into wasteland.
Questions and tasks
1.What are called plains? What surface can the plains have?
2. How are plains distinguished by height?
3. On the scale of heights in the atlas, determine what color each of the types of leveling in height is marked with. Give examples of each type of plain.
4. What plains are there in Ukraine?
5. The Dnieper divides Ukraine into the Right Bank and the Left Bank. On the physical map of Ukraine, determine which one is higher.
6. How are plains formed?
7. Under the influence of what processes can the surface of the plains change?
