The natural conditions of South America are diverse and contrasting. According to the nature of the structure of the surface on the mainland, two parts are distinguished. In the east, for the most part, low-lying, elevated plains and plateaus predominate, in the west - the longest mountain ranges of the Andes. The formation of the Andes began in the Paleozoic and has not ended so far. The Andes continue to rise, volcanoes erupt, strong earthquakes occur.

South America is the wettest continent on Earth. The abundance of precipitation is facilitated by the Andes, blocking the path of westerly winds. There is a dense river network here, including the largest rivers in the world - the Amazon and the Parana. In the Andes, at an altitude of 3800 m, lies the largest alpine lake in the world - Titicaca.

Due to the predominance of a hot, humid climate on the continent, forests are widespread in South America and there are relatively few deserts and semi-deserts. The highland climate of the Andes is very diverse. It changes both when ascending from the foot of the mountains to the peaks and when moving from the Northern Andes to the Southern.

South America is rich in mineral deposits. The Andes are home to the largest deposits of copper ores, silver, tin, and lead. There are fuses of gold. This contributed to the rather early development of metallurgy here.

The zone of high civilizations of antiquity in South America occupied the region of the Central Andes. From the east, the Central Andes are bounded by the forests of the Amazon basin, from the west by the ocean. The northern periphery is formed by the territory of modern Ecuador. In southern Peru and Bolivia, the area of ​​ancient civilizations extended to approximately 17oS. However, from the beginning of the 1st millennium BC. The southern Andes, with the exception of the central regions of Chile and the eastern slopes of the Argentine Andes, were included in the orbit of the cultural influence of the Central Andean civilizations.

Human economic activity in the Andes is possible up to a height of 4.5 km. On the plateaus of the Central Andes, isolated from the influence of the ocean, there are dry mountain steppes and semi-deserts, called puna. Pune is divided into lower, suitable for agriculture and upper, suitable only for grazing. On the central plateaus of the Andes, located in the tropical zone, the air is exceptionally clean and dry. Little precipitation falls as snow even in summer. The weather changes not only by seasons, but also during the day, and sharply and several times. A person can hardly tolerate such a climate. Pune stretches from northern Chile to central Peru. Further towards Ecuador, it is replaced by alpine meadows, called paramo in South America. Pune and Paramo differ in relief, climate, flora and fauna, so these zones were mastered in antiquity by different groups of tribes.

The peculiarity of the natural environment in the far north of Peru (desert, replaced by savannah and warmer waters of the Pacific Ocean) in comparison with the more southern regions significantly influenced the course of ethnic and economic processes. This site turned out to be an insurmountable obstacle for the cold-loving alpaca (genus llamas) domesticated on the plateaus of Bolivia and Peru.

Below Puna, there are warmer valleys and pits, mostly characterized by an arid climate, so the development of agriculture here required irrigation. The eastern slopes of the mountains occupy cold, rainy areas with poor soils. The forested regions below were not part of the zone of distribution of the Central Andean civilization, but their population sometimes penetrated to the west, playing a certain role in the history of ancient Peru.

The natural resources of the Central Andean region are much richer than those of Mesoamerica. Here were the necessary conditions for the cultivation of potatoes and other mountain root crops, corn, pumpkin, quinoa, and beans. On the coast - for growing cotton and tropical root crops: sweet cassava, sweet potato and others. There were also prerequisites for the development of cattle breeding - the wild llama.

The lower belt of mountains facing the Pacific Ocean is arid and dissected by steep gorges. There is almost no population here. Next comes the coastal plain. In the north of Peru, it reaches a width of 50 km. The cold Humboldt current determines the characteristics of the coastal climate. It's not hot here. Summer and winter differ slightly in temperature. Life on the coast is concentrated where mountain rivers come out onto the plain or there are sources of groundwater. The oases are separated from each other by patches of desert 20-40 km wide. They are fertile and favorable for life. Thanks to the supply of nutrients off the coast of Peru, one of the richest biosystems of marine organisms in the world has developed.

The distribution of natural resources determined the spatial structure of the Central Andean civilization. From the very beginning, two relatively independent centers were outlined in it. In the mountains, the best opportunities for the development of a manufacturing economy existed in the south of the region in the basin of Lake Titicaca. Here are the most extensive pastures and fields. The freshwater reservoir itself was of considerable economic importance.

On the coast, the center of development was shifted to the north. The oases here are the most extensive, and the sea is the richest. The extreme south coast of Peru was heavily influenced by the cultures of the Titicaca basin. The mountainous regions in the north were influenced by coastal cultures. The cultural interaction was most complex in central Peru.

The climate of the continent is changing - from sultry equatorial zones in the north, near the equator, - with separate cold areas in the highlands, - to frosty polar regions in the extreme south, from where it is a stone's throw to icy Antarctica.

South America is one of the two continents of the Earth that are intersected by the equator. Unlike Africa, the equator crosses the mainland in the northern part. The mainland is located entirely in the western hemisphere. From the west, the mainland is washed by the Pacific Ocean, from the east - by the Atlantic. Closer to other continents to South America is North America. The mainland is separated from Antarctica by the Drake Passage.

Angel Falls is the highest in South America. This is the world's highest waterfall (979m.) on the Churun ​​River falls from a flat-topped tepui, known as the "Devil's Mountain". The waterfall got its name from the American James Angel, whose plane crashed here in 1937.

The amazing Amazon, overflowing with rainwater (from 2,650 to 3,000 mm of precipitation falls annually), the Amazon River brings 643 billion liters of water to the Atlantic Ocean every hour. The river begins its journey in the Peruvian Andes and flows through the Amazon Basin, which occupies 40 percent of the entire territory of Brazil. Here are several million species of plants and animals - more than half of the flora and fauna of the entire Earth. There are many unusual exotic animals here: hummingbirds, sloths, jaguars, piranhas.

Climatic conditions are very varied. North of the country up to 40? NL located in the temperate climate zone, south - in the subtropical, south of Florida - in the tropical. The Cordilleras limit the influence of the Pacific Ocean on the central and eastern parts of the country, air masses from the north and south freely penetrate there. Therefore, a narrow strip along the coast of the Pacific Ocean and the extreme southeast have an oceanic climate; a continental climate prevails in the rest of the country.

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Introduction

South America is almost completely isolated from other continents. From the west it is washed by the waters of the Pacific Ocean, from the east and north by the Atlantic. In the south, the wide Drake Passage separates South America from Antarctica, in the north, the mainland is washed by the waters of the Caribbean Sea. Only the narrow Isthmus of Panama connects South America with North America.

Most of South America lies in the southern hemisphere, in the equatorial and subequatorial belts. Only the narrowed part of the mainland enters the subtropical and temperate latitudes of the southern hemisphere.

The formation of the animal world of the mainland was influenced by the contrasts of natural conditions, the features of paleogeographic development and the long-term isolation of the continent from the main land mass. Therefore, the Neogean fauna is distinguished by a high level of endemism, great originality, and, along with this, defectiveness.

The modern fauna, like the flora of the mainland, was formed starting from the end of the Cretaceous period.

In this control work, a description of the natural conditions of South America is given, a general description of the animal world is given, examples of species endemism of animals characteristic of this continent are considered, features of the Neogean fauna are shown, examples of the main national parks and protected areas of the continent are given, a map of the animal world and the main national parks in South America.

The purpose of this examination is to conduct characteristics of the animal world of South America.

To achieve this goal, the following tasks were set:

1. Consider the geographical location of South America.

2. Describe the geological structure.

3. Show the significance of the relief in the formation of the mainland.

4. Reveal the features of climatic conditions.

5. Consider the hydrographic network.

6. Describe the land cover.

7. Show the originality of the Neogean fauna.

8. Give examples of the main national parks in South America and show their importance.

1. Geographical location and features of natural conditions

South America is now almost completely isolated from other continents. Only by the narrow Isthmus of Panama, finally formed only in the Pliocene, is it connected with Central and North America. Vast oceanic expanses separate South America from other continents. South America includes the Falkland (Malvinas) Islands, the islands of Trinidad and Tobago lying on the shelf of the Atlantic Ocean, in the Pacific Ocean - the Galapagos Islands, Juan Fernandez and the coastal Chonos archipelago with the large island of Chiloe.

The area of ​​South America with the islands is 17.8 million km 2. The border of South America in the north is considered to be a conditional line passing along the Atrato River, and offset to the Darien Gulf.

The northern extremity of the mainland is Cape Galinas (12 0 28 / N), the southern one is Cape Frouerd in the Strait of Magellan (53 0 54 / S). Further south on the island of the same name is Cape Horn (56 0 S), which is also sometimes considered the southern limit of the continent. The extreme western point is Cape Parinhas (81 0 20 / W), the eastern one is Cape Cabo Branco (34 0 47 /). The mainland reaches its greatest width (more than 5000 km) at 5 0 S.l. Thus, most of South America is located mainly in the equatorial and tropical latitudes of the Western Hemisphere. In shape, the mainland resembles a triangle with a base in the northern part, near the equator, and a top in the south. This configuration of the mainland has a significant impact on its natural features. South America also includes the island of Tierra del Fuego, separated from the mainland by a narrow and long (550 km) Strait of Magellan, which connects the Atlantic Ocean with the Pacific. At its narrowest point, the strait is up to 3.5 km wide and up to 35 m deep. The strait is a flooded fjord with high steep banks. The shores of South America are slightly indented, only in the southwest the fjord type prevails, and in the north the wide bay of Maracaibo juts out into the mainland, connected to the lake of the same name.

The geological structure of South America is determined by two large structural elements of the earth's crust: the ancient, Precambrian, South American platform and the geosynclinal belt of the Andes, which has been actively developing since the Late Precambrian.

Mineral deposits are also closely related to the geological structure. The richest iron ore deposits are confined to the ancient shields of the platform - in the center and on the outskirts of the Brazilian Plateau (in Bolivia) and in the north of the Guiana Plateau (in Venezuela). In the ancient weathering crust of the crystalline basement on these plateaus, there are large reserves of manganese and nickel. As a result of weathering on the wet outskirts of the plateaus, especially the Guiana, bauxite deposits with an alumina content of up to 67% were formed. The total bauxite reserves in South America are equal to 2500 million tons. In the depressions of the plateaus, in the troughs of the Amazon and the Patagonian plate, there are deposits of oil, natural gas and coal. The main oil and gas deposits are confined to foothill foredeep and intermountain depressions of the Andes. Oil reserves are especially rich in the depression of Maracaibo and the Magdalena River, in the area of ​​the Gulf of Guayaquil. Oil fields have been discovered in the southeast of the mainland - in Patagonia and on the adjacent shelf, but unlike the northern ones, they have only focal distribution.

The Andes mountain ranges are rich in non-ferrous and rare metals. The largest reserves of copper and molybdenum ores are known in southwestern Peru and western Chile. Bolivia has significant reserves of tin. Brazil holds a leading position in the reserves of bauxite, titanium, copper, lead, zinc, tin, manganese ores.

The bowels of South America are rich in iron, manganese, tungsten, nickel and molybdenum. The total iron ore reserves of South America account for 38% of all the resources of the capitalist world. Brazil, Venezuela, Peru and Chile are richest in iron ores. Brazil ranks first in the capitalist world in iron ore reserves. Most of the deposits are located in the eastern part of the country. More than 100 iron ore deposits have been discovered in the state of Minas Jeiras. Iron ore mining in the country is 90-95%. Venezuela has the second largest iron ore resources in Latin America. The largest deposits are located in the lower reaches of the Orinoco River.

The relief of South America has some similarities with the relief of North America, which is associated with the presence of a wide geosynclinal zone in the west of both continents. The Andes of South America are a continuation of the Cordilleras of North America. The western parts of the continents are occupied by extensive mountain systems, while the eastern parts are much lower. The Andes of South America are on average taller than the Cordilleras.

The relief of South America is represented by two unequal parts: the plain-flat-mountain Out-Andean East; mountainous Andean West. In the east, vast plains stand out - the Amazonian, La Platskaya, Orinokskaya, the stepped plateau of Patagonia and the Guiana, Brazilian plateau. The average height of the mainland is 580 m, which is lower than Asia, North America, Antarctica, but higher than Europe and Australia. The main peak of the mainland - Mount Aconcagua (6960) is inferior to many of the highest peaks in Asia.

Several large morphostructural regions are distinguished in the Out-Andean East. These include: Amazonia, which occupies a vast territory from the foothills of the Andes to the Atlantic Ocean with an area of ​​over 5 million km 2, lying in the trough of the South American platform; the Orinoco Plain, stretching from the foothills of the Andes to the Orinoco Delta, is a low stratified plain composed of Tertiary sandstones; the Guiana coast, up to 200 km wide, serves as its continuation; The internal plains occupy a trough between the Andes, the Brazilian Plateau and Patagonia, composed of a thick layer of continental sediments, from Devonian to Quaternary with a flat, slightly dissected relief. In the north and south there are mid-altitude remnant massifs. Along the central part of the trough of the rivers of Paraguay and the lower Parana, the La Plata lowland stretches. In the north, it begins with a young tectonic depression (Pantanal), the Chaco plains, and in the south it ends with Pampa. The uniformity of the relief of the Eastern Pampas is broken in the south by two groups of low mountains and hills - the Sierra del Tandil and the Sierra de la Ventana. These mountains are highly flattened, eroded and affected by tertiary faults and uplifts. In the southwest, the region of the Cis-Cordillera and the Pampina Sierras adjoins the internal plains, blocky flat-topped massifs 2000-6000 m high.

The most extensive uplift of the South American Platform forms the Brazilian Plateau, which gradually rises from north (100 m) to south (600 m) and forms the Goias plateau in the south (1000-1200 m). The table-like surfaces of individual plateaus are ancient leveling surfaces, limited by vertical ledges - chapads. In the south, the plateau breaks off with a series of ledges. The highest point of the Brazilian plateau is the Bandeira massif (2890 m). The Guiana Highlands in the north are framed by the Guiana Lowland. In the north, the relief is represented by gently undulating peneplain. To the west of the Orinoco River, ancient crystalline rocks in the form of remnant mountains come to the surface. The Patagonian plateau forms a system of ledges, gradually descending towards the Atlantic Ocean; in the west, the plateau gradually rises to the Andes.

The Andean West is one of the highest mountain systems in terms of height, extent and expression of alpine landforms, second only to the Tibetan-Himalayan, 20 peaks rise in them to a height of more than 6000 m. The entire Andean mountain system serves as an important climate divide, is difficult to pass, creates a general impression of asymmetry macrorelief.

The climate of South America is determined by the geographical position of this territory, the planetary system of atmospheric circulation, and the features of the relief.

Most of South America is located in the equatorial, subequatorial, tropical and subtropical zones, only a narrow southern part of the mainland, not exceeding 600 km wide, goes into temperate latitudes. Almost on the entire continent, the radiation balance reaches 111-355 kJ/cm 2 .

The main part of the mainland is located in the zone of trade wind circulation with a predominance of northeast winds to the north of the equator, and southeast winds to the south. Air masses move towards South America from the peripheral regions of the Azores (in the north) and South Atlantic (in the south) anticyclones. Therefore, the types of climate in South America are determined by the influence of the air masses of the Atlantic, and not the Pacific Ocean. The absence of large orographic barriers inside the mainland allows the Atlantic masses to go far to the west, to the very slopes of the Andes. Vast areas of South America are constantly exposed to significant heating, the pressure over a wide part of the mainland at the level of the earth's surface is much lower than over the oceans washing it.

The south of the mainland is located in the zone of westerly winds, under their influence is Southern Chile and part of Patagonia. To the south of the mainland there is a wide strip of low pressure of a planetary character.

The system of ocean currents associated with the general circulation of the atmosphere affects the climate of the coastal regions of the mainland. The warm Brazilian Current increases the moisture content of trade wind air masses, the cold Falkland Current increases the aridity of the Patagonian climate, and the cold Peruvian Current contributes to the formation of desert landscapes.

The atmospheric circulation system changes with the seasons. In December-February, the northeast trade wind crosses the equator, the area of ​​the southeast trade wind narrows, and the westerly wind zone shifts to the south. At this time, it is summer in the Southern Hemisphere. Equatorial air masses recede to the south, to the northern, northwestern and western parts of the Brazilian Highlands, to the depression of the upper Parana and to the Gran Chaco plains, causing seasonal rains characteristic of subequatorial latitudes.

In June-August (winter in the Southern Hemisphere), the atmospheric circulation system shifts to the north. From the southern and southwestern periphery of the Azores High, northeastern trade winds come to the shores of South America, which, moving over heated waters, are saturated with moisture. In the Western Amazon, equatorial air prevails, causing showers. The dry southeast trade wind from the Brazilian Highlands penetrates into the Eastern Amazonia, which does not bring a significant amount of precipitation. The southeast trade wind from the northern periphery of the South Atlantic High irrigates the northeast ledge of the Brazilian Highlands. And the winds from the western edge of the South Atlantic High carry moist and warm tropical air, which penetrates the interior of the mainland and irrigates the eastern outskirts of the Brazilian Highlands.

Along with the shift of the air circulation system to the north in June-August, the influence of the westerly winds of the Southern Hemisphere increases, which affect a significant part of Chile. In connection with the shift to the north of the South Pacific anticyclone, the air masses flowing from its periphery moisten Central Chile, replenishing the moisture brought by the western winds of the Southern Hemisphere. West coast, slopes and intermountain plateau of the Andes from 30 0 S.l. to the equator in winter are under the influence of the eastern periphery of the South Pacific anticyclone. All west between 30 0 S.l. and the equator turns out to be sharply arid and anomalously cooled. North of the equator, northwesterly winds bring heavy rainfall to the northwest Cordillera.

The thermal regime of South America is characterized by slight fluctuations. The entire north of the mainland, the Amazon and the west of the Brazilian Highlands are very warm throughout the year; the average July temperature is +25 0 C. Winter cooling affects the mountainous east of the Brazilian Highlands and the plains of Pampa, the average July temperature is +10-+12 0 C, on the high plateaus of Patagonia - about +5 0 C. Intrusions from the south of cold air temperate latitudes cause irregular frosts in the Pampas. The average July temperatures on the island of Tierra del Fuego are +2 0 C. In the summer months of the Southern Hemisphere, the southern parts of the mainland receive more heat, but there are no high temperatures here, since cold currents limit the summer heat. The hottest places at this time of the year are in the central regions of the Gran Chaco, in the north of Argentina and Paraguay (maximum up to +40 0 C). This is below the maximum in Africa (+58 0), North America or Asia.

Most of South America has sufficient moisture. The wettest areas of the mainland are Western Colombia and Southern Chile, where the annual precipitation reaches 5000-8000 mm. Up to 2000-3000 mm of precipitation falls in the western Amazon and on the adjacent slopes of the Andes, the windward eastern slopes of the Guiana Highlands and the central part of the eastern slopes of the Brazilian Highlands. The remaining parts of the slopes receive less than 1000 mm of precipitation per year. Insufficient moisture in the Pampas (300-400 mm) and in Central Chile (200-300 mm). Patagonia and the Precordillera region are very arid (150-200 mm per year). The Pacific coast areas between 5 and 28 0 S are especially arid. with adjacent western slopes and intermountain plateaus of the Andes (Atacama Desert).

Colombia and the Western Amazon receive rainfall throughout the year. In Central Chile, precipitation falls in winter.

In South America, three climatic sectors can be distinguished with different types of climate: the climate of the east, the climate of the Pacific coast and the mountain climate.

The equatorial constantly humid climate is typical for most of the Amazon and the adjacent slopes of the Andes.

Throughout the year, equatorial air masses dominate with temperature (+25-+27 0 C) and significant humidity (precipitation is 2000-4000 mm per year). Humidification is uniform, but there are two precipitation maxima. The weather regime during the day is the same. Usually in the morning hours, temperatures gradually increase and the moisture content in the air increases. There are thunderstorms in the afternoon.

The seasonally humid subequatorial climate is established in the territories located to the north and south of the equator. These include the lowlands of the Orinoco and Magdalena rivers, the coastal regions of Venezuela, the Guiana Highlands, most of the Brazilian Highlands (except the east and south). Equatorial air masses dominate in summer, tropical air masses dominate in winter. This type of climate is characterized by humid, hot summers and dry, hot winters. The average summer temperatures are +25-+28 0 C, winter - +20 - +30 0 C. The amount of precipitation reaches 1500 mm per year. With distance from the equator, the duration of the dry period increases, and with approaching the equator, the duration of the wet period increases. The northeast of the Brazilian Highlands is characterized by a sharp aridity.

The tropical climate is typical for areas located south of territories with a subequatorial climate. Tropical air masses dominate throughout the year. There are tropical humid and tropical dry climates.

The subtropical climate is confined to the interfluve of the Parana and Uruguay, the plains of the Pampas and the Precordillera region up to - 41 0 S.l. Tropical air masses dominate in summer, moderate air masses in winter. Humidification in these areas is uniform. Hot summer. Winter is mild and cool. The flat character of the interfluve contributes at this time of the year to the invasion far to the north of the cold air masses of the Antarctic. Cold gusty winds blow two or three times during the winter in the Pampas and in the south of the Brazilian Highlands, which causes frost and snowfall.

A temperate climate is formed on the plains of Patagonia. The amount of precipitation is negligible. The minimum is -35 0 С. With a small amount of precipitation, temperature contrasts are small; this is explained by the fact that Patagonia is located in the zone of influence of the westerly winds of the Southern Hemisphere. But the heavy rainfall brought by these winds is delayed by the Andes mountain ranges. In terms of moisture, Patagonia resembles a desert, in terms of temperature amplitude, it resembles a maritime climate. The equatorial humid climate is established on the Pacific coast from 6 0 S.l. to the equator; it is characterized by high

uniform temperatures throughout the year (+25-+27 0 C), heavy rainfall of 5000 mm or more.

A subequatorial seasonally humid climate is formed in the territories located south of the equator up to 4 0 30 / S; characterized by dry hot winters (June-November) and humid hot summers (November-May).

The tropical trade wind climate is the climate of the coastal deserts of Peru and Chile. These include Sechura and Atacama. This part of the mainland receives precipitation in the form of abundant dew, formed by dense fog, often enveloping the slopes of the Peruvian and Chilean Andes at an altitude of 400-1000 m.

The subtropical (Mediterranean) climate is typical for territories located from 28 to 37 0 30/S, with a clearly pronounced seasonality of precipitation and temperatures. This area is characterized by hot dry summers (December-February) and relatively cool rainy winters (June-August). The Mediterranean type of climate is formed because in summer the air masses of the South Pacific Ocean High (eastern periphery) move to this area; in winter, this area is under the influence of cyclonic rains brought by westerly winds.

To the south, the characteristic features of the Mediterranean climate gradually disappear, westerly winds play an increasingly important role, and features of a humid oceanic temperate climate appear (Southern Chile). The western transfer of air masses contributes to abundant precipitation - up to 6000 mm per year. Especially a lot of precipitation falls on the western slopes of the Andes (on average, it rains 325 days a year). Precipitation is evenly distributed throughout the seasons. Cool rainy weather prevails with strong western winds.

The Andes mountain system, due to its height, serves as a climatic boundary separating the Pacific air masses from the Atlantic ones, and forms a mountain climate. Temperatures gradually decrease with height, the amount of precipitation increases to 1000-1500 mm, and starts to decrease higher, which contributes to the formation of a dry climate.

The equatorial Andes (from 5 0 N) are under the influence of equatorial air. On the eastern slopes, up to 400 mm of precipitation falls annually; on the western slopes - more than 8000. In the capital of Ecuador, Quito, the temperature is about +13 0 С; light frosts are set at night, during the day it rises to + 22- + 24 0 С.

The mountain variety of the subequatorial and tropical climate is typical for mountainous regions lying between 5 and 30 0 S.l.

The climate of the intermountain plateaus is arid, but relatively high temperatures persist.

South of 40 0 ​​S The Andes are characterized by a cold damp climate with large clouds, strong, frequent precipitation. A stable snow cover and modern glaciation form in the mountains. The eastern slopes are characterized by an arid climate, as the Pacific air, crossing the mountain range and descending the eastern slope, becomes drier. Precipitation falls 200-400 mm per year. Summer is cold. In winter, frosts in the valleys reach -40 0 С.

The formation of a dense, well-developed river network of South America is favored by the configuration of the mainland, climatic conditions and the nature of the relief, in particular the Andes mountain system, which forms the main watershed. The watershed line coincides with the largest uplifts, and only in the Andes of Patagonia passes to the east.

South America accounts for 8% of the earth's land mass and 14% of its runoff. Under the influence of the moist winds of the Atlantic, South America receives twice as much precipitation as the average of the entire land mass of the Earth. South America is richer in water resources than other continents. The total and underground runoff of this continent is almost twice as much as in Europe, which ranks second in terms of wealth in water resources.

Most of the rivers of the continent are rain-fed, glacial is important only in the south of the Andes; the role of snow nutrition is negligible. As a result of the abundant moisture of the mainland and the shift of the watershed to the extreme west in South America, great water systems were formed despite the relatively small size of the mainland.

The largest river in South America is the Amazon. The length of the Amazon (Maranion) is 6437 km. Despite a slight average slope, the river has a strong current due to its water content. The area of ​​the catchment basin is 7 million km2. The average flow of the river at the mouth is 120 thousand m 3 /s, the maximum is about 200 thousand m 3 /s. The average annual flow of the Amazon is 5000 km 3, which makes up most of the flow of the entire South America and 15% of the flow of all the rivers of the globe. The Amazon is the most abundant river in the world in terms of water volume. The Amazon is the second longest river in the world.

The source of the Amazon is the Marañon River, which flows out of Lake Patacocha, located in the Peruvian Andes at an altitude of over 4000 m. The Amazon has more than 17 tributaries. In the lower reaches of the river, tides have a great influence on its regime and formation. The tidal wave penetrates upstream for about 1400 km and causes strong waves on sandbars and banks, destroying the banks. Thanks to the tides and full water of the Amazon, the largest ocean-going ships can reach the city of Manaus, and sea ships can reach Iquitos. The largest tributary of the Amazon is the Madeira. The right tributary of the Amazon is larger than the left. In addition to Madeira, these are Zhurua, Purus, Tapajos, Xingu. Twice a year the level of the Amazon rises by several meters. These maxima are associated with rainy periods in both the Northern and Southern Hemispheres. At this time, the river in the middle reaches floods a huge territory, then gradually it enters the banks (August-September). Then the second maximum occurs, associated with the period of summer rains in the Northern Hemisphere. On the Amazon, it appears in November. When it flows into the ocean, the Amazon divides into many branches and forms an archipelago. The largest among the islands is Marajo.

The Paraguay-Parana river basin is the largest in South America after the Amazon basin. The basin area of ​​the entire system is 4 million km 2, the length of the Parana is 4700 km. These, as well as other rivers of the system, originating in the Brazilian Highlands, form waterfalls in their upper reaches, the largest of which is Iguazu, 72 m high.

The most important tributary of the Parana is Paraguay, which opens waterways to the central parts of the mainland and the Amazon.

The Uruguay River in its upper course flows through the trap plateau, following the general slope to the west and descending from a height of 1000 m to 100 m. Below the confluence of the Rio Negro, it is replete with rapids and rapids.

La Plata, which collects the waters of Parana and Uruguay, resembles a giant funnel open to the Atlantic Ocean. Its width at the mouth is 222 km, length 320 km.

The Orinoco River originates in the Guiana Highlands. The Orinoco regime is fickle. The level of the river depends on the rainfall that falls in the northern part of its basin in the summer (May-September). The largest waterfalls in the world are located in the Orinoco basin on the Guiana Plateau. Angel Falls is widely known.

Lake Titicaca is the largest alpine lake in the world. It is located at an altitude of 3812 m above sea level on the border between Peru and Bolivia. The area of ​​the lake is 8300 km 2, the maximum depth is 304 m. Terraces are pronounced on the shores of the lake, indicating a repeated decrease in its level.

Lakes of glacial origin are concentrated in the Southern Andes. These are freshwater lakes with very dissected shores. For example, lakes Nahuel Huapi, San Martin). They were formed as a result of the damming of the runoff of glacial melt waters by terminal moraines, which filled wide trough valleys.

Along the shores of the Atlantic Ocean there are large lagoon lakes, the largest of which is Maracaibo, connected to the Gulf of Venezuela.

Groundwater is an important source of South America's water resources. The total underground runoff of the mainland is 3740 km 3.

The formation of the rich and diverse flora of South America is closely connected with the history of the geological development of the continent, modern orography and climatic conditions.

Young types of meadow-steppe, semi-desert shrub formations of Patagonia formed in the post-glacial period from the Antarctic flora, forming in the south of the continent the second center of speciation of the South American flora - the Antarctic one, which was preserved mainly in Tierra del Fuego and in the Patagonian Andes. In the Antarctic floristic kingdom, a very peculiar endemic flora, not rich in species composition, has formed.

The formation of the soil cover is closely related to the climate, moistening of the territories and the development of vegetation.

The soils of South America do not form continuous homogeneous spaces, such as on the plains of Eurasia and North America. In South America, various types of lateritic soils are predominant, confined to hot areas with constant and abundant moisture. For territories with seasonal moisture, red, brown-red and brown soils are typical, which are successively replaced by gray-brown and gray soils to the west inland. Reddish-black and chernozem-like fertile soils are formed in the pampas. In cool temperate latitudes, soils are represented by brown forest soils in the west, chestnut and desert-steppe soils in the east, turning into swampy meadow and peaty soils in Tierra del Fuego.

In the Andean mountain system, the features of the soil cover are associated with altitudinal zonality, exposure of slopes, the presence of high mountain plateaus, and the location of mountain ranges. Each latitudinal geographical zone in the Andes has its own type of soil. Significant territories are occupied by mountain red soils, brown forest, podzolic and mountain meadow soils. Brownish, desert and alpine desert-steppe soils are widespread in the Andes.

Desert and high-mountain desert-steppe soils are developed in the Patagonian Andes, Precordillera and Pampina sierras.

The vast plains in the east of South America are very diverse in terms of natural conditions. Each plain and each plateau is a special natural complex, often having its own names. Today in the lesson we will get acquainted with the nature of some of them. These are the Amazon and the Brazilian Highlands.

Subject: Continents. South America

Lesson: Natural areas of mainland South America: Plain East

Today in class we will learn:

how low-lying plains and plateaus are distinguished according to natural conditions, what types of economic activities are common in the flat territories, and what are the environmental problems associated with human activities.

The largest natural areas allocated on the mainland are the flat East and the mountainous West (Andes). Within these areas, smaller natural complexes are distinguished, differing in geological structure, relief, climate and organic world features.

Huge flat swampy lowland with a dense network of full-flowing rivers of the Amazon basin (see Fig. 1).

The main features of the nature of the Amazon are determined by its flat relief, long-term continental development and equatorial position. This planet's greatest region of equatorial climate and tropical rainforest accounts for most of the basin of Earth's deepest river system.

The boundaries of the Amazon are clearly defined by the slopes of the Brazilian and Guiana highlands and the eastern foot of the Andes.

Rice. 1. Amazonia

This area covers an area of ​​about 5 million square meters. km. In size, it surpasses the physical and geographical regions of not only South America, but also other continents.

The main features of the nature of the Amazon are determined by its flat relief and equatorial position. These two factors determine the characteristics of the climate, flora and fauna of the region.

Innumerable natural resources are concentrated in the Amazon - forests with huge reserves of food, technical and medicinal raw materials, building and ornamental materials. In the bowels there are various minerals. All these riches are poorly explored and are used very little. In a significant part of the territory of the region, nature has retained its original appearance, not changed or slightly changed by human impact.

Rice. 2. Amazonian lowland ()

The Amazonian lowland is an area of ​​prolonged subsidence within the platform and has low altitudes and a uniform flat topography almost throughout its territory (see Fig. 2). Even at the very foot of the Andes, the height of its surface does not exceed 100 m above sea level.

The climate here is predominantly equatorial with two periods of heavy rainfall (see Fig. 3). Especially heavy rains fall there from February to June and from October to January.

The entire region is characterized by high and uniform temperatures with little seasonal variation. With uniform and high average temperatures in the Amazon, there is no intense heat, but even temperatures of 24 - 27 ° are difficult for people to endure there due to the constant strong humidity of the air and the lack of night coolness. Rains usually fall in the form of heavy and prolonged showers in the afternoon, and clear weather occurs in the evening and at night.

Rice. 3. Climatic features of the Amazon

These features of climatic conditions favor the development of moisture-loving tropical forests with their diverse and lush vegetation.

This plant mass, the richest on Earth, has, especially in the west of the Amazon, innumerable resources of food, technical and medicinal raw materials, building and ornamental materials. The Amazon Basin plays an important role in global metabolism, accounting for about 10% of the Earth's primary biological production.

The species composition and appearance of forests varies depending on the position in relation to the rivers. Periodic floods of the Amazon and its tributaries have a great influence on vegetation. In this regard, different types of forest vegetation are distinguished on the lowlands: forests in river valleys, flooded for several months a year (the local population calls them "igapo"); forests in river valleys that are flooded for a short time (they are called "varzeya"); forests in the watersheds, not flooded at all (known as "ete"). In addition, the aquatic vegetation of the Amazon itself and other rivers, as well as mangroves on the Atlantic coast, stand out.

Although the fauna of the Amazon as a whole is very rich, yet in the virgin forests such abundance is not striking. The dense rainforests of the Amazon are generally poor in large animals. Most of them are found on the outskirts of forests and along rivers. Birds and insects, reptiles and amphibians predominate.

Rice. 4. Wildlife of the Amazon ()

The fauna of the Amazon and its tributaries is especially rich (see Fig. 4). There are up to 2000 species of fish, including predatory piranhas; large mammals (manatees, freshwater dolphins, capybaras), reptiles (river turtles, caimans). Along the banks of rivers and lakes, spending a significant part of the time in the water, lives a giant anaconda boa constrictor.

Brazilian and Guiana Highlands - main core of eastern South America.

Between the flat low plains of the Amazon and Parana basins in the north and west and the Atlantic Ocean in the east, a territory with an elevated and dissected relief extends for about 5 million km 2. it brazilian highlands(or, in other terminology, a plateau) (see Fig. 5).

This area is almost as large in size as the Amazon. At the same time, it is characterized by a wide variety of landscapes. The main features of its nature are determined by the predominance of the relief of plateaus and table plateaus and the dominance of subequatorial and tropical climates. Only by its southern outskirts does the Brazilian Highlands enter subtropical latitudes.

Rice. 5. Brazilian Plateau ()

The long-term impact of erosion processes, changes in the structure of the earth's crust under the influence of recent tectonic movements have created a wide variety of relief within the highlands, where areas of crystalline plateaus are combined with insular highlands composed of sedimentary rocks, volcanic plateaus and blocky ridges formed as a result of Cenozoic faults and uplifts.

From the Atlantic Ocean, the eastern and southeastern margins of the Brazilian Highlands look like high and heavily dissected mountains. As a result of the fragmentation and uplift of the East Brazilian Shield in the Neogene, ridges, or "sierras", were formed that reach a height of more than 2000 m. The highest point of the highlands - Mount Bandeira (2890 m) - is located within the Kaparao National Park.

In the northern spurs of the plateaus in the Serra dos Carajas region, one of the greatest iron ore basins of the planet was discovered, where, in addition to high-quality iron ore, there are deposits of manganese, copper, chromium, nickel ores, bauxite and other valuable minerals (see Fig. 6). It was there, in the area of ​​mining and to the factories under construction, that the railway line was laid from the Atlantic Ocean, crossing the Eastern Amazon.

Rice. 6. Map of mineral resources ()

In the west and north, the Brazilian Highlands are bordered by lowlands. Its edges then abruptly break off, forming ledges several hundred meters high, then they decrease rather gently. There are many rapids and waterfalls on the rivers cutting through the edge of the crystalline plateau. Low-lying areas covered with tropical forests penetrate far into the highlands along the river valleys.

The climatic conditions of the region are varied. Almost all of this vast territory is characterized by the division of the year into two periods - wet and dry. The duration of the wet and dry periods and the annual precipitation in different parts of the region are different, which is reflected in the nature of the vegetation cover and the appearance of the cultural landscape.

The Brazilian Highlands are dominated by savannas and tropical woodlands. The two most common types of savanna are campos-limpos and campos-serrados.

This is the common name of the savannas, adopted in Brazil (see Fig. 7). Campos-limpos are characterized by the complete absence of woody vegetation. The area is a continuous sea of ​​grasses, and this remotely resembles the steppes of the temperate zone. Among the herbs are various types of feather grass, bearded vulture, wheatgrass, as well as representatives of the Umbelliferae, Lamiaceae and legume families.

All these plants burn out and turn brown during the dry period, only small cacti and agaves retain their appearance unchanged all year round. With an outward resemblance to the steppe, campos-limpos differs from it in a much greater diversity of species composition. For every 2-3 m 2 of the surface, up to 200-250 plant species can be counted.

In campos cerrados, trees and shrubs grow along with herbs. Trees with a height of no more than 3-5 m usually have an umbrella-shaped crown. Grasses in the shade of trees can reach 1-2m in height and grow so densely that during the wet season the terrain becomes impassable. In the savannas, fires are frequent, which sometimes cover vast areas.

In the north-east of the highlands, which is characterized by great dryness, the typical savanna gradually turns into a kind of tropical forest - caatinga, where the vegetation is adapted to a long drought (see Fig. 8).

The vegetation cover in the Caatinga consists of trees and shrubs with an almost complete absence of grasses.

Rice. 8. Caatinga ()

Many trees have swollen trunks and soft, porous wood that holds large amounts of moisture. The trunks of other trees are thin, and the crowns are very spreading. Many woody and shrubby plants have thorns. Therefore, the terrain is difficult to pass, although individual plants stand at fairly considerable distances from each other. Of the most typical plants of Caatinga, cacti of various forms, prickly pear and euphorbia are interesting. Among the latter there are rubber plants. There are also several types of palms, including the carnauba wax palm.

With the onset of rains, the caatinga changes its appearance very quickly. According to eyewitnesses, you can fall asleep in the evening in a forest scorched by the sun, devoid of leaves and flowers, and after a night rain wake up in a completely different environment: in a few hours the forest is transformed - many plants are covered with leaves, bright flowers bloom on them.

Tropical rain forests grow along the eastern edge of the highlands, along the slopes of the serres and on the rolling coastal plain. From the ocean itself, they begin with a wide strip of mangroves, which then pass into a forest that is very reminiscent of the forests of the Amazon. Cecropia, palm trees, tree ferns, creepers, including a kind of bamboo creeper, various epiphytes are common in it.

Monkeys live in the forests, even close to settlements, causing great harm to gardens and crops; Everywhere an abundance of birds, especially parrots and hummingbirds; of predators, cougars and jaguars are typical, snakes and other reptiles are very common.

There are many ants in the forests and savannahs. Some of them settle near human habitation and cause great trouble to people. An integral feature of the savanna landscape is termite mounds.

The Brazilian Highlands with its unique complex of natural resources (the most valuable reserves of mineral raw materials, hydropower, climate and soils favorable for agriculture, the richness of the organic world) are inhabited and developed unevenly, therefore, the degree of change in natural landscapes in its individual parts is different.

The most populated strip adjacent to the Atlantic Ocean. The largest cities are located there - Sao Paulo (in 2000, the population - 17.7 million people) and Rio de Janeiro (10.6 million people) - and industry is developed.

Many large cities are so plagued by air pollution, particularly from vehicle emissions, that some, such as São Paulo, impose restrictions on the use of private cars. Despite adding alcohol to gasoline and reducing carbon dioxide emissions by about 30%, there was no measurable improvement in urban air quality.

In the Paraná basin, the largest areas of plowed land are concentrated, on which coffee trees, tobacco, bananas, and vines are grown. On the irrigated lands of the river valleys, especially in the north, rice crops are widespread.

In the humid north, sugar cane and oil palm are grown, in drier places, the coffee tree. In the northeast, which suffers most from droughts, cotton is cultivated on irrigated lands. In the inner parts of the highlands, vast areas are occupied by savannahs and secondary thickets used as pastures.

The gradual settlement of vast areas of the South American selva also did not go unnoticed for this territory. Since the early 1960s the population within the Brazilian Amazon increased 10 times and by 2002 reached 20 million people. As a rule, settlement was accompanied by uncontrolled deforestation, as well as the destruction of unique species of flora and fauna. A sharp reduction in the area of ​​Amazon forests is also evidenced by observational data from space.

Rice. 9. Deforestation of the Amazon ()

Since 2000, the Amazon has been implementing a large-scale economic development plan called "Avansa Brasil", which involves the construction of new roads and railways, gas pipelines, power plants, power lines and other infrastructure. As a result of the implementation of this project according to the planned plan within the Brazilian Amazon by the middle of the XXI century. up to 40% of forests can be destroyed.

Scientists argue that if the Brazilian authorities do not take emergency measures to protect the Amazon in the very near future, the matter may end in an environmental disaster not only on a regional, but also on a planetary scale.

It should not be forgotten that the Amazonian selva is, figuratively speaking, the "green lungs" of the Earth, as it largely affects the chemical composition and temperature regime of the atmosphere, as well as the distribution of precipitation. Therefore, a sharp reduction in the area of ​​equatorial forests will inevitably lead to a change in the climate of the entire Earth.

Each continent has a special characteristic that significantly distinguishes it from others. One can speak of South America as the continent of natural phenomena.

Looking at a map of the world, you can see that America consists of two large continents and thus forms a single part of the world.

Between themselves, two continents (North and South America) are connected by the long Isthmus of Panama, in one of the parts of which the Panama Canal was laid.

general characteristics

The area of ​​South America is 18 million km2, the mainland is located entirely in the Western Hemisphere.

The mainland of South America stretches from north to south for about 7 thousand kilometers, and from west to east - for about 5 thousand. It narrows towards the southern end.

Cape Froward is considered the southernmost point of the mainland, Cape Gallinas is the northernmost point, Cape Cabo Branco is the easternmost point, and Cape Parinas is the westernmost point.

But the continents of America were not always interconnected - when they were separated, their development took place independently of each other.

Crosses South America equator, and 10% of its territory is located in the northern hemisphere. Thus, most of the mainland is in the southern hemisphere.

Since the southern tropic passes through its territory, this determines the presence of certain belts - tropical, equatorial and subequatorial. And the southern part of the mainland belongs to the temperate and subtropical zone.

South America can be referred to as humid mainland. The southern part of the mainland is narrowed, while the northern and central ones are expanded. The southern part is dominated by the tropical zone, which leads to a large amount of precipitation.

The Atlantic Ocean, which washes the eastern territory, has a significant impact on the natural conditions of the mainland. Due to the fact that there are plains in this territory, moist air masses penetrate South America without obstacles.

And warm caribbean sea, the only one in South America, washes the northern coast. The Brazilian and Guiana currents also contribute to an increase in humidity on the mainland. Famous bays of South America: San Jorque, La Plata, Bahia Grande and San Matias, but none of them can be called large.

The influence of the Pacific Ocean falls on the southern and western coasts of the mainland. But it cannot be called significant, since it is limited Andean mountain system. This part of the mainland is characterized by cold ocean currents (for example, the Peruvian Current).

And the extreme southern strip of the mainland is separated from Antarctica by the Drake Passage, and, despite this, the influence of the natural conditions of this mainland on the nature of this part of South America is quite noticeable.

South America is entirely in the Western Hemisphere. In the north, South America is connected to North America through the Isthmus of Panama. The southern, narrowed and dissected part of the mainland is known as Central America. North America reaches its greatest width in temperate and subpolar latitudes.

Of all the continents, North America extends farthest to the north. Its elongation from the polar latitudes almost to the very equator led to a huge variety of natural conditions. And a significant length from west to east led to the formation of a continental climate in the interior of the mainland. Its length is the largest of all the continents of the Earth and is 75,600 km. The mainland is washed by three oceans: the Pacific in the west, the Atlantic in the east and the Arctic in the north.

Geographic research

The mainland is crossed by the Southern Tropic. The coastline is very poorly indented. Only in the southeast there are several not very large bays: La Plata, San Matias, San Jorge and Baia Grande. Together they form a single part of the world - America. Cape Froward is considered the southernmost point of the mainland, Cape Gallinas is the northernmost point, Cape Cabo Branco is the easternmost point, and Cape Parinas is the westernmost point. Thus, most of the mainland is in the southern hemisphere.

The southern part is dominated by the tropical zone, which leads to a large amount of precipitation. Due to the fact that there are plains in this territory, moist air masses penetrate South America without obstacles.

general characteristics

Famous bays of South America: San Jorque, La Plata, Bahia Grande and San Matias, but none of them can be called large. The influence of the Pacific Ocean falls on the southern and western coasts of the mainland. And the extreme southern strip of the mainland is separated from Antarctica by the Drake Passage, and, despite this, the influence of the natural conditions of this mainland on the nature of this part of South America is quite noticeable.

North and South America, together with the adjacent islands, are traditionally combined into one part of the world, called America. But according to natural conditions, these continents are two completely different worlds, due to differences in geographical location and in the history of their development. North America stretches from the polar latitudes almost to the equator.

To the north are Greenland and the Canadian Arctic Archipelago. Many islands adjoin North America in the northwest and west: the Aleutian, Queen Charlotte, Vancouver, the Alexander Archipelago. The northernmost island point in North America is Cape Morris Jesup in Greenland (83° 39′ N). This is the land closest to the pole in the northern hemisphere. The seas deeply dissect the eastern and northern coasts of the mainland, and to a much lesser extent, its western coast.

Spanish expeditions XV-XVI

The waters of the Arctic Ocean, washing the northeastern and northern coasts of the mainland, constantly have a low temperature. The Baffin Inter-Island Sea washes the eastern shores of the Baffin Islands and Devon Islands and the southeast of Ellesmere Island. The Baffin Sea is connected by a system of narrow straits to the northernmost of all Arctic seas, the Lincoln Sea.

The Pacific coast of North America, with the exception of the northern segment, is much less dissected than the Atlantic. Almost everywhere at a relatively short distance from the mainland in the Pacific Ocean, great ocean depths prevail. The area of ​​the mainland together with the islands is 24,247 thousand km2, the area of ​​the islands is 3,890 thousand km2. In the extreme north and south, the land is heavily dissected by water basins. All the main orographic zones of North America are extended along the strike of the continent itself.

In terms of geographical location and features of development, North America has much in common with Eurasia. These continents are characterized by common patterns of climate formation and the same types of climate, similar types of zonal landscapes, relief, etc.

North America is similar to Eurasia, but at the same time it has its own unique geographical features. The coast of the mainland is indented quite weakly. Most of the bays are not large, they are formed at the mouth of the rivers when the ocean moves deep into the mainland. The average height of the mainland is quite small, which is explained by the large territory occupied by the lowlands: the Amazonian, Orinoco and La Plata.

brazilian plateau

In Chile there are huge deposits of saltpeter. South America is extremely rich in inland waters due to the humid climate and the abundance of plains. The Amazon collects water from 40% of the territory of South America, in the lower reaches its width reaches 20 km, the river is also very deep, which allows even ships to pass far inland.

The geographical location and topography of the mainland lead to the fact that the climate of South America is warm and very humid. The entire northern and most of the central part of the mainland are in the equatorial and subequatorial climatic zones.

Between these zones there is a zone of continental subtropical climate, here it is dry, hot (+25°С) summer and warm (+10°С) winter. The temperate belt occupies the southern tip of the mainland. A temperate maritime climate is formed on the west coast, with warm winters, cool summers and abundant rainfall.

The shores of North America are washed by the waters of three oceans: the Atlantic, the Arctic and the Pacific. From west to east in the widest part about 5 thousand, however, for the most part its extent is small, and the continent narrows towards its southern tip. South America is crossed by the equator, and 10% of its territory is located in the northern hemisphere.