Andes (mountains). Southern Andes, Patagonia and Tierra del Fuego

The Andes Mountains serve as the most important climatic barrier in South America, isolating the territories west of the Main Cordillera from influence Atlantic Ocean, to the east - from the influence of the Pacific Ocean. The mountains lie in 6 climatic zones (equatorial, northern and southern subequatorial, southern tropical, subtropical and temperate) and are distinguished by sharp contrasts in the moisture content of the eastern and western slopes.

Due to the considerable extent of the Andes, their individual landscape parts differ significantly from each other. Based on the nature of the relief and other natural differences, as a rule, three main regions are distinguished - Northern, Central and Southern Andes. The Andes stretch across the territories of seven South American countries - Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile and Argentina.

Highest point: Aconcagua (6962 m)

Length: 9000 km

Width: 500 km

Rocks: igneous and metamorphic

The Andes are revived mountains, erected by new uplifts on the site of the so-called Andean (Cordilleran) folded geosynclinal belt; The Andes are one of the largest systems of alpine folding on the planet (on the Paleozoic and partly Baikal folded basement). The beginning of the formation of the Andes dates back to Jurassic time. The Andean mountain system is characterized by troughs formed in the Triassic, subsequently filled with layers of sedimentary and volcanic rocks of considerable thickness. Large massifs of the Main Cordillera and the coast of Chile, the Coastal Cordillera of Peru are granitoid intrusions of Cretaceous age. Intermountain and marginal troughs (Altiplano, Maracaibo, etc.) were formed in Paleogene and Neogene times. Tectonic movements, accompanied by seismic and volcanic activity, continue in our time. This is due to the fact that a subduction zone runs along the Pacific coast of South America: the Nazca and Antarctic plates go under the South American plate, which contributes to the development of mountain building processes. The southernmost part of South America, Tierra del Fuego, is separated by a transform fault from the small Scotia plate. Beyond the Drake Passage, the Andes continue the mountains of the Antarctic Peninsula.

The Andes are rich in ores of mainly non-ferrous metals (vanadium, tungsten, bismuth, tin, lead, molybdenum, zinc, arsenic, antimony, etc.); the deposits are confined mainly to the Paleozoic structures of the eastern Andes and the vents of ancient volcanoes; There are large copper deposits on the territory of Chile. There is oil and gas in the foredeep and foothill troughs (in the foothills of the Andes within Venezuela, Peru, Bolivia, Argentina), and bauxite in the weathering crusts. The Andes also contain deposits of iron (in Bolivia), sodium nitrate (in Chile), gold, platinum and emeralds (in Colombia).

The Andes consist primarily of meridional parallel ridges: the Eastern Cordillera of the Andes, the Central Cordillera of the Andes, the Western Cordillera of the Andes, the Coastal Cordillera of the Andes, between which lie internal plateaus and plateaus (Puna, Altipano - in Bolivia and Peru) or depressions. The width of the mountain system is generally 200-300 km.

Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile, Argentina Length 8000 km Width 500 km highest peak Aconcagua Andes on Wikimedia Commons

Andes, Andean Cordillera(Spanish) Andes; Cordillera de los Andes ) - the longest (9000 km) and one of the highest (Mount Aconcagua, 6962 m) mountain systems on Earth, bordering all of South America from the north and west; southern part of the Cordillera. In some places, the Andes reach a width of over 500 km (the greatest width - up to 750 km - in the Central Andes, between 18° and 20° S). The average altitude is about 4000 m.

The Andes are a major interoceanic divide; To the east of the Andes flow the rivers of the Atlantic Ocean basin (the Amazon itself and many of its large tributaries, as well as the tributaries of the Orinoco, Paraguay, Parana, Magdalena River and Patagonia River originate in the Andes), to the west - the Pacific Ocean basin (mostly short ones).

The Andes serve as the most important climatic barrier in South America, isolating the territories to the west of the Main Cordillera from the influence of the Atlantic Ocean, and to the east from the influence of the Pacific Ocean. The mountains lie in 5 climatic zones (equatorial, subequatorial, tropical, subtropical and temperate) and are distinguished (especially in the central part) by sharp contrasts in the moisture content of the eastern (leeward) and western (windward) slopes.

Due to the considerable extent of the Andes, their individual landscape parts differ significantly from each other. Based on the nature of the relief and other natural differences, as a rule, three main regions are distinguished - Northern, Central and Southern Andes.

The Andes stretch across the territories of seven South American countries - Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile and Argentina.

History of the name

According to the Italian historian Giovanni Anello Oliva (g.), initially by European conquerors “ Andes or Cordilleras" ("Andes, o cordilleras") was called the eastern ridge, while the western one was called " Sierra"("sierra").

Geological structure and relief

The Andes are reborn mountains, erected by new uplifts on the site of the so-called Andean (Cordilleran) folded geosynclinal belt; The Andes are one of the largest systems of alpine folding on the planet (on the Paleozoic and partly Baikal folded basement). The beginning of the formation of the Andes dates back to Jurassic time. The Andean mountain system is characterized by troughs formed in the Triassic, subsequently filled with layers of sedimentary and volcanic rocks of considerable thickness. Large massifs of the Main Cordillera and the coast of Chile, the Coastal Cordillera of Peru are granitoid intrusions of Cretaceous age. Intermountain and regional troughs (Altiplano, Maracaibo, etc.) were formed in Paleogene and Neogene times. Tectonic movements, accompanied by seismic and volcanic activity, continue in our time. This is due to the fact that a subduction zone runs along the Pacific coast of South America: the Nazca and Antarctic plates go under the South American plate, which contributes to the development of mountain building processes. The southernmost part of South America, Tierra del Fuego, is separated by a transform fault from the small Scotia plate. Beyond the Drake Passage, the Andes continue the mountains of the Antarctic Peninsula.

The Andes are rich in ores of mainly non-ferrous metals (vanadium, tungsten, bismuth, tin, lead, molybdenum, zinc, arsenic, antimony, etc.); the deposits are confined mainly to the Paleozoic structures of the eastern Andes and the vents of ancient volcanoes; There are large copper deposits on the territory of Chile. There is oil and gas in the foredeep and foothill troughs (in the foothills of the Andes within Venezuela, Peru, Bolivia, Argentina), and bauxite in the weathering crusts. The Andes also contain deposits of iron (in Bolivia), sodium nitrate (in Chile), gold, platinum and emeralds (in Colombia).

The Andes consist primarily of meridional parallel ridges: the Eastern Cordillera of the Andes, the Central Cordillera of the Andes, the Western Cordillera of the Andes, the Coastal Cordillera of the Andes, between which lie internal plateaus and plateaus (Puna, Altiplano - in Bolivia and Peru) or depressions. The width of the mountain system is generally 200-300 km.

Orography

Northern Andes

The main system of the Andes (Andean Cordillera) consists of parallel ridges stretching in the meridional direction, separated by internal plateaus or depressions. Only the Caribbean Andes, located within Venezuela and belonging to the Northern Andes, stretch sublatitudinally along the coast of the Caribbean Sea. The northern Andes also include the Ecuadorian Andes (in Ecuador) and the Northwestern Andes (in western Venezuela and Colombia). The highest ridges of the Northern Andes have small modern glaciers, and eternal snow on the volcanic cones. The islands of Aruba, Bonaire, and Curacao in the Caribbean Sea represent the peaks of the extension of the Northern Andes that descend into the sea.

In the Northwestern Andes, fan-shaped diverging north of 12° N. sh., there are three main Cordilleras - Eastern, Central and Western. All of them are high, steeply sloped and have a folded blocky structure. They are characterized by faults, uplifts and subsidences of modern times. The main Cordilleras are separated by large depressions - the valleys of the Magdalena and Cauca-Patia rivers.

The Eastern Cordillera has its highest altitude in its northeastern part (Mount Ritakuva, 5493 m); in the center of the Eastern Cordillera - an ancient lake plateau (predominant heights - 2.5 - 2.7 thousand m); The Eastern Cordillera is generally characterized by large planation surfaces. In the highlands there are glaciers. In the north, the Eastern Cordillera is continued by the Cordillera de Merida (highest point - Mount Bolivar, 5007 m) and Sierra de Perija (reaches a height of 3,540 m); Between these ranges, in a vast low-lying depression, lies Lake Maracaibo. In the far north there is the Sierra Nevada de Santa Marta horst massif with altitudes up to 5800 m (Mount Cristobal Colon)

The Magdalena River Valley separates the Eastern Cordillera from the Central Cordillera, which is relatively narrow and high; in the Central Cordillera (especially in its southern part) there are many volcanoes (Hila, 5750 m; Ruiz, 5400 m; etc.), some of which are active (Kumbal, 4890 m). To the north, the Central Cordillera decreases somewhat and forms the Antioquia massif, strongly dissected by river valleys. The Western Cordillera, separated from the Central Valley by the Cauca River, has lower altitudes (up to 4200 m); in the south of the Western Cordillera - volcanism. Further to the west is the low (up to 1810 m) Serrania de Baudo ridge, which turns into the mountains of Panama in the north. To the north and west of the Northwestern Andes are the Caribbean and Pacific alluvial lowlands.

As part of the Equatorial (Ecuadorian) Andes, reaching up to 4° S, there are two Cordilleras (Western and Eastern), separated by depressions 2500-2700 m high. Along the faults that limit these depressions (depressions) there is one of the highest volcanic volcanoes in the world chains (the highest volcanoes are Chimborazo, 6267 m, Cotopaxi, 5897 m). These volcanoes, as well as those of Colombia, form the first volcanic region of the Andes.

Central Andes

In the Central Andes (up to 28° S) the Peruvian Andes (extending south to 14°30 S) and the Central Andes proper are distinguished. In the Peruvian Andes, as a result of recent uplifts and intensive incision of rivers (the largest of which - Marañon, Ucayali and Huallaga - belong to the upper Amazon system), parallel ridges (Eastern, Central and Western Cordillera) and a system of deep longitudinal and transverse canyons were formed, dismembering the ancient alignment surface . The peaks of the Cordillera of the Peruvian Andes exceed 6000 m (the highest point is Mount Huascaran, 6768 m); in the Cordillera Blanca - modern glaciation. Alpine landforms are also developed on the blocky ridges of the Cordillera Vilcanota, Cordillera de Vilcabamba, and Cordillera de Carabaya.

To the south is the widest part of the Andes - the Central Andean Highlands (width up to 750 km), where arid geomorphological processes predominate; A significant part of the highland is occupied by the Puna plateau with altitudes of 3.7 - 4.1 thousand m. Puna is characterized by drainage basins (“bolsons”) occupied by lakes (Titicaca, Poopo, etc.) and salt marshes (Atacama, Coipasa, Uyuni, etc. .). East of Puna is the Cordillera Real (Ankouma Peak, 6550 m) with thick modern glaciation; between the Altiplano plateau and the Cordillera Real, at an altitude of 3700 m, is the city of La Paz, the capital of Bolivia, the highest in the world. To the east of the Cordillera Real are the sub-Andean folded ridges of the Eastern Cordillera, reaching up to 23° S. latitude. The southern continuation of the Cordillera Real is the Cordillera Central, as well as several blocky massifs (the highest point is Mount El Libertador, 6720 m). From the west, Puna is framed by the Western Cordillera with intrusive peaks and numerous volcanic peaks (Sajama, 6780 m; Llullaillaco, 6723 m; San Pedro, 6159 m; Misti, 5821 m; etc.), included in the second volcanic region of the Andes. South of 19° S. the western slopes of the Western Cordillera face the tectonic depression of the Longitudinal Valley, occupied in the south by the Atacama Desert. Behind the Longitudinal Valley is the low (up to 1500 m) intrusive Coastal Cordillera, which is characterized by arid sculptural landforms.

In Puna and in the western part of the Central Andes there is a very high snow line (in places above 6,500 m), so snow is recorded only on the highest volcanic cones, and glaciers are found only in the Ojos del Salado massif (up to 6,880 m in height).

Southern Andes

The Andes near the border of Argentina and Chile.

In the Southern Andes, extending south of 28° S, two parts are distinguished - northern (Chilean-Argentine or Subtropical Andes) and southern (Patagonian Andes). In the Chilean-Argentine Andes, narrowing to the south and reaching 39°41 S, a three-member structure is clearly expressed - the Coastal Cordillera, the Longitudinal Valley and the Main Cordillera; within the latter, in the Cordillera Frontal, there is the highest peak of the Andes, Mount Aconcagua (6960 m), as well as the large peaks of Tupungato (6800 m), Mercedario (6770 m). The snow line here is very high (at 32°40 S - 6000 m). To the east of the Cordillera Frontal are the ancient Precordilleras.

South of 33° S. (and up to 52° S) is the third volcanic region of the Andes, where there are many active (mainly in the Main Cordillera and to the west of it) and extinct volcanoes (Tupungato, Maipa, Llymo, etc.)

When moving south, the snow line gradually decreases and at 51° S. latitude. reaches 1460 m. High ridges acquire features of the Alpine type, the area of ​​modern glaciation increases, and numerous glacial lakes appear. South of 40° S. The Patagonian Andes begin with lower ridges than in the Chilean-Argentine Andes (the highest point is Mount San Valentin - 4058 m) and active volcanism in the north. About 52° S the strongly dissected Coastal Cordillera plunges into the ocean, and its peaks form a chain of rocky islands and archipelagos; The longitudinal valley turns into a system of straits reaching the western part of the Strait of Magellan. In the area of ​​the Strait of Magellan, the Andes (called the Andes of Tierra del Fuego) sharply deviate to the east. In the Patagonian Andes, the height of the snow line barely exceeds 1500 m (in the extreme south it is 300-700 m, and from 46°30 S latitude glaciers descend to ocean level), glacial landforms predominate (at 48° S latitude - powerful Patagonian ice sheet) with an area of ​​over 20 thousand km², from where many kilometers of glacial tongues descend to the west and east); some of the valley glaciers on the eastern slopes end in large lakes. Along the coasts, heavily indented by fjords, young volcanic cones rise (Corcovado and others). The Andes of Tierra del Fuego are relatively low (up to 2469 m).

Climate

Northern Andes

The northern part of the Andes belongs to the subequatorial belt of the northern hemisphere; here, as in the subequatorial zone of the southern hemisphere, there is an alternation of wet and dry seasons; Precipitation falls from May to November, but in the most northern regions the wet season is shorter. The eastern slopes are moistened much more than the western ones; Precipitation (up to 1000 mm per year) falls mainly in summer. In the Caribbean Andes, located on the border of the tropical and subequatorial zones, tropical air dominates throughout the year; there is little rainfall (often less than 500 mm per year); The rivers are short with characteristic summer floods.

In the equatorial belt, seasonal variations are practically absent; Thus, in the capital of Ecuador, Quito, the change in average monthly temperatures over the year is only 0.4 °C. Precipitation is abundant (up to 10,000 mm per year, although usually 2500-7000 mm per year) and is distributed more evenly along the slopes than in the subequatorial belt. Altitudinal zonation is clearly expressed. In the lower part of the mountains there is a hot and humid climate, precipitation falls almost daily; in the depressions there are numerous swamps. With altitude, the amount of precipitation decreases, but the thickness of the snow cover increases. Up to altitudes of 2500-3000 m, temperatures rarely drop below 15 °C; seasonal temperature fluctuations are insignificant. There are already large daily temperature fluctuations here (up to 20 °C), the weather can change dramatically during the day. At altitudes of 3500-3800 m, daily temperatures fluctuate around 10 °C. Higher up there is a harsh climate with frequent snow storms and snowfalls; Daytime temperatures are positive, but there are severe frosts at night. The climate is dry, as there is little precipitation due to high evaporation. Above 4500 m there is eternal snow.

Central Andes

Between 5° and 28° S. There is a pronounced asymmetry in the distribution of precipitation along the slopes: the western slopes are moistened much less than the eastern ones. To the west of the Main Cordillera there is a desert tropical climate (the formation of which is greatly facilitated by the cold Peruvian Current), and there are very few rivers. If in the northern part of the Central Andes 200-250 mm of precipitation falls per year, then to the south their amount decreases and in some places does not exceed 50 mm per year. This part of the Andes is home to the Atacama, the driest desert on earth. Deserts rise in places up to 3000 m above sea level. The few oases are located mainly in the valleys of small rivers fed by the waters of mountain glaciers. The average January temperature in coastal areas ranges from 24 °C in the north to 19 °C in the south, and the average July temperature ranges from 19 °C in the north to 13 °C in the south. Above 3000 m, in dry puna, there is also little precipitation (rarely more than 250 mm per year); There are arrivals of cold winds when the temperature can drop to −20 °C. The average July temperature does not exceed 15 °C.

At low altitudes, with very little rain, there is significant (up to 80%) air humidity, which is why fog and dew are frequent. The Altiplano and Puna plateaus have a very harsh climate, with average annual temperatures not exceeding 10 °C. The large Lake Titicaca has a softening effect on the climate of the surrounding areas - in the lakeside areas, temperature fluctuations are not as significant as in other parts of the plateau. To the east of the Main Cordillera there is a large amount of precipitation (3000 - 6000 mm per year) (brought mainly in the summer by easterly winds), a dense river network. Along the valleys, air masses from the Atlantic Ocean cross the Eastern Cordillera, moistening its western slope. Above 6000 m in the north and 5000 m in the south - negative average annual temperatures; Due to the dry climate, there are few glaciers.

Southern Andes

In the Chilean-Argentine Andes the climate is subtropical, and the humidification of the western slopes - due to winter cyclones - is greater than in the subequatorial zone; When moving south, annual precipitation amounts on the western slopes increase rapidly. Summer is dry, winter is wet. As you move away from the ocean, the climate becomes more continental and seasonal temperature fluctuations increase. In the city of Santiago, located in the Longitudinal Valley, the average temperature of the warmest month is 20 °C, the coldest month is 7-8 °C; There is little precipitation in Santiago, 350 mm per year (to the south, in Valdivia, there is more precipitation - 750 mm per year). On the western slopes of the Main Cordillera there is more precipitation than in the Longitudinal Valley (but less than on the Pacific coast).

When moving south, the subtropical climate of the western slopes smoothly transforms into the oceanic climate of temperate latitudes: annual precipitation amounts increase, and differences in moisture between seasons decrease. Strong westerly winds bring to the coast a large number of precipitation (up to 6000 mm per year, although usually 2000-3000 mm). It rains heavily for more than 200 days a year, thick fog often falls on the coast, and the sea is constantly stormy; the climate is unfavorable for living. The eastern slopes (between 28° and 38° S) are drier than the western ones (and only in the temperate zone, south of 37° S, due to the influence of westerly winds, their moisture increases, although they remain less humid compared to Western ones). The average temperature of the warmest month on the western slopes is only 10-15 °C (the coldest month is 3-7 °C)

In the extreme southern part of the Andes, Tierra del Fuego, there is a very humid climate, which is formed by strong, humid westerly and southwesterly winds; Precipitation (up to 3000 mm) falls mainly in the form of drizzle (which occurs most days of the year). Only in the easternmost part of the archipelago is there much less precipitation. Temperatures are low throughout the year (with very little temperature variation between seasons).

Vegetation and soils

The soil and vegetation cover of the Andes is very diverse. This is due to the high altitudes of the mountains and the significant difference in moisture content between the western and eastern slopes. Altitudinal zonation in the Andes is clearly expressed. There are three altitudinal zones - Tierra Caliente, Tierra Fria and Tierra Elada.

On the slopes of the Patagonian Andes south of 38° S. - subarctic multi-tiered forests of tall trees and shrubs, mostly evergreen, on brown forest (podzolized to the south) soils; there are a lot of mosses, lichens and lianas in the forests; south of 42° S - mixed forests (in the area of ​​42° S there is an array of araucaria forests). Beeches, magnolias, tree ferns, tall conifers, and bamboos grow. On the eastern slopes of the Patagonian Andes there are mainly beech forests. In the extreme south of the Patagonian Andes there is tundra vegetation.

In the extreme southern part of the Andes, Tierra del Fuego, forests (of deciduous and evergreen trees - such as southern beech and canelo) occupy only a narrow coastal strip in the West; Above the forest line, the snow belt begins almost immediately. In the east and in some places in the west, subantarctic mountain meadows and peatlands are common.

Copper Mountains - this is what the Incas call these longest mountains in the world. We are talking about the Andean Cordillera, known to us as the Andes. This mountain range is not comparable in length to any existing on our planet. The length of the Andes is about 9 thousand km. They originate from the Caribbean Sea and reach Tierra del Fuego.

Width and height of the Andes

Aconcagua (pictured below) is the highest peak of the Andean Cordillera. The height of the Andes at this point is 6962 meters. Aconcagua is located in Argentina. What are the predominant ones have a number of large peaks. Among them, it is worth noting Mount Ritakuva (5493 meters), El Libertador (6720 meters), Huascaran (6768 meters), Mercedario (6770 m), etc. There are areas where the mountains reach 500 km in width. As for their maximum width, it is about 750 km. Their main part is occupied by the Puna plateau, which has a very high snow line, which reaches 6500 m. The average height of the Andes is approximately 4000 m.

Age of the Andes and their formation

According to experts, these mountains are quite young. Several million years ago, the process of mountain building ended here. The emergence of fossils began in the Precambrian period. Land areas then began to appear in place of the vast ocean. The area where the modern Andean Cordillera is located, for a long time was sometimes sea, sometimes land, and the height of the Andes varied significantly. The mountain range completed its formation after the uplift of rocks. Huge folds consisting of stone, as a result of this process, extended to an impressive height. By the way, this process is not over. It continues in our time. Volcanic eruptions and earthquakes sometimes occur in the Andes.

Rivers originating in the Andes

The longest mountains on our planet are at the same time considered the largest interoceanic watershed. The famous Amazon originates precisely in the Andean Cordillera, as do its tributaries. It should also be noted that the tributaries of the major rivers of the states of Paraguay, Orinoco and Parana begin in the Andes. For the mainland, the mountains are a climatic barrier, that is, they protect the land from the west from the influence of the Atlantic Ocean, and from the east from the influence of the Pacific Ocean.

Relief

The Andes have a large extent, so it is not surprising that they are found in six climate zones. Unlike the southern slopes, the amount of precipitation on the western slopes is high. It reaches 10 thousand mm per year. Consequently, not only the height of the Andes, but also its landscape varies significantly.

The Andean Cordillera is divided into 3 regions according to its relief: Central, Northern and Southern Andes. The main Cordilleras are separated by depressions of rivers such as the Magdalena and Cauca. There are many volcanoes located here. One of them, Huila, reaches a height of 5750 m. The other, Ruiz, rises to 5400 m. Kumbal, which is now active, reaches a height of 4890 m. The Ecuadorian Andes, classified as the Northern Andes, include a volcanic chain marked by the highest volcanoes. Chimborazo alone is worth something - it rises to 6267 m. The height of Cotopaxi is not much less - 5896 m. The highest point of the Ecuadorian Andes is Huascaran - 6769 m is the absolute height of the mountain. The Southern Andes are divided into Chilean-Argentine and Patagonian. The highest points in this part are Tupungato (about 6800 m) and Medcedario (6770 m). The snow line reaches six thousand meters here.

Volcano Llullaillaco

This is a very interesting active volcano located on the border of Argentina and Chile. It belongs to the Peruvian Andes (Western Cordillera range). This volcano is located in the Atacama Desert, which is one of the driest places on our planet. The absolute height of the Andes at this point is 6739 m. It is the highest of all active ones. In the area of ​​this volcano, the Andes mountains are very unique. Its relative height reaches 2.5 km. On the western slope of the volcano, the snow line exceeds 6.5 thousand m, which is its highest position on the planet.

Atacama Desert

This unusual place contains areas where it has never rained. The Atacama Desert is the driest place on Earth. The fact is that the rains cannot overcome so they fall on the other side of the mountains. The sands in this desert extend thousands of kilometers into the tropics. The cold fog rising from the sea is the only source of moisture for local plants.

San Rafael Glacier

Another interesting place, which I would like to talk about is the San Rafael glacier. It should be noted that in the south of the Alpine Cordillera, where it is located, it is very cold. At one time, this greatly surprised the pioneers, since the south of France and Venice lie at the same latitude in the northern hemisphere, and here they discovered the San Rafael glacier. It moves, cutting off the slopes of mountains, the peaks of which become sharper and steeper over time. It was only in 1962 that its source was discovered. A gigantic ice sheet cools the entire region.

Vegetation

The Andes are a unique place on our planet, and not only because of the impressive width and height of the mountains. The Andes are incredibly picturesque. In different places they have their own flavor. In the Andes Mountains of Venezuela, for example, shrubs and deciduous forests grow on red soils. Equatorial and tropical rainforests cover the lower slopes from the Northwestern to Central Andes. Here you can find bananas, ficus trees, cocoa trees, palm trees, vines and bamboos. However, there are also rocky, lifeless spaces and many mossy swamps. In places where the average height of the Andes exceeds 4500 m, there is an area of ​​​​perpetual ice and snow. The Andean Cordillera is known as the birthplace of coca, tomatoes, tobacco and potatoes.

Animal world

The fauna of these mountains is no less interesting. Llamas, alpacas, pudú deer, vicuñas, spectacled bears, blue foxes, sloths, hummingbirds, and chinchillas live here. Residents of our country can find all these animals only in zoos.

One of the features of the Andes is the large diversity of amphibian species (about 900). About 600 species of mammals live in the mountains, as well as about two thousand species of birds. The variety of freshwater fish is also great. There are about 400 species in local rivers.

Tourism and locals

The Andean Cordillera, apart from remote and rugged areas, is not an untouched corner of nature. Local residents cultivate almost every piece of land here. However, the road to the Andes for most tourists means “escape” from modernity. For centuries, these places have maintained an unchanged way of life, which allows tourists to feel like they are in the past.

Travelers can follow ancient Indian trails, where, however, sometimes they need to stop to let a herd of guanacos, sheep or goats pass ahead. No matter how many times you have already visited these local places, it is always fascinating. Meetings with local residents also turn out to be unforgettable. Their way of life is far from what we are used to. The huts in these places are built from rough bricks. Local residents often go without electricity. In order to get water, they go to the nearest stream.

Hiking in the mountains is not mountaineering in the usual sense of the word. Rather, these are walks along steep paths. However, they should only be performed by absolutely healthy and well-trained people who have special equipment.

The Andes are a major interoceanic divide. To the east of the Andes flow the rivers of the Atlantic Ocean. The Amazon itself and many of its major tributaries, as well as tributaries of the Orinoco, Paraguay, Paraná, Magdalena River and Patagonian River, originate in the Andes. To the west of the Andes flow mostly short rivers belonging to the Pacific Ocean basin.

The Andes also serve as the most important climatic barrier in South America, isolating the territories to the west of the Main Cordillera from the influence of the Atlantic Ocean, and to the east from the influence of the Pacific Ocean.

The mountains lie in 5 climatic zones:

• equatorial,
• subequatorial,
• tropical,
• subtropical,
• moderate.

They are distinguished by sharp contrasts in the moisture content of the eastern (leeward) and western (windward) slopes.

Due to the considerable extent of the Andes, their individual landscape parts differ from each other. Based on the nature of the relief and other natural differences, as a rule, three main regions are distinguished - Northern, Central and Southern Andes.

The Andes stretch across the territories of 7 countries in South America:

• Venezuela,
• Colombia,
• Ecuador,
• Peru,
• Bolivia,
• Chile,
• Argentina.

Vegetation and soils

The soil and vegetation cover of the Andes is very diverse. This is due to the high altitudes of the mountains and the significant difference in moisture content between the western and eastern slopes. Altitudinal zonation in the Andes is clearly expressed. There are three altitudinal zones - Tierra Caliente, Tierra Fria and Tierra Elada.

The Andes Mountains of Venezuela are home to deciduous forests and shrubs on mountainous red soils.

The lower parts of the windward slopes from the Northwestern Andes to the Central Andes are covered with montane moist equatorial and tropical forests on lateritic soils (montane hylaea), as well as mixed forests of evergreen and deciduous species. The appearance of equatorial forests differs little from the appearance of these forests in the flat part of the continent; Characterized by various palm trees, ficuses, bananas, cocoa trees, etc.

Higher (up to altitudes of 2500-3000 m) the nature of the vegetation changes; typical are bamboos, tree ferns, coca bush (which is a source of cocaine), and cinchona.

Between 3000 m and 3800 m - high-mountain hylea with low-growing trees and shrubs; Epiphytes and lianas are widespread, bamboos, tree ferns, evergreen oaks, myrtaceae, and heathers are typical.

Higher up there is predominantly xerophytic vegetation, paramos, with numerous Asteraceae; moss swamps on flat areas and lifeless rocky areas on steep slopes.

Above 4500 m there is a belt of eternal snow and ice.

To the south, in the subtropical Chilean Andes - evergreen shrubs on brown soils.

In the Longitudinal Valley there are soils whose composition resembles chernozems.

Vegetation of the high mountain plateaus: in the north - mountain equatorial meadows of paramos, in the Peruvian Andes and in the east of Puna - dry high-mountain tropical steppes of the halka, in the west of Puna and throughout the Pacific west between 5-28 ° south latitude - desert types of vegetation (in the Atacama Desert - succulent vegetation and cacti). Many surfaces are saline, which prevents the development of vegetation; In such areas, mainly wormwood and ephedra are found.

Above 3000 m (up to about 4500 m) there is semi-desert vegetation called dry puna; Dwarf shrubs (tholoi), grasses (feather grass, reed grass), lichens, and cacti grow.

East of the Cordillera Main, where there is more rainfall, - steppe vegetation(puna) with numerous grasses (fescue, feather grass, reed grass) and cushion-shaped shrubs.

On the humid slopes of the Eastern Cordillera, tropical forests (palm trees, cinchona) rise to 1500 m, low-growing evergreen forests with a predominance of bamboo, ferns, and lianas reach 3000 m; at higher altitudes there are high-mountain steppes.

A typical inhabitant of the Andean highlands is polylepis, a plant of the Rosaceae family, common in Colombia, Bolivia, Peru, Ecuador and Chile; these trees are also found at an altitude of 4500 m.

In central Chile the forests have been largely cleared; Once upon a time, forests rose along the Main Cordillera to altitudes of 2500-3000 m (higher up were mountain meadows with alpine grasses and shrubs, as well as rare peat bogs), but now the mountain slopes are practically bare. Nowadays, forests are found only in the form of individual groves (pines, araucarias, eucalyptus, beeches and plane trees, with gorse and geranium in the undergrowth).

On the slopes of the Patagonian Andes south of 38° S. - subarctic multi-tiered forests of tall trees and shrubs, mostly evergreen, on brown forest (podzolized to the south) soils; there are a lot of mosses, lichens and lianas in the forests; south of 42° S - mixed forests (in the area of ​​42° S there is an array of araucaria forests). Beeches, magnolias, tree ferns, tall conifers, and bamboos grow. On the eastern slopes of the Patagonian Andes there are mainly beech forests. In the extreme south of the Patagonian Andes there is tundra vegetation.

In the extreme southern part of the Andes, Tierra del Fuego, forests (of deciduous and evergreen trees - such as southern beech and canelo) occupy only a narrow coastal strip in the west; Above the forest line, the snow belt begins almost immediately. In the east and in some places in the west, subantarctic mountain meadows and peatlands are common.

The Andes are the birthplace of cinchona, coca, tobacco, potatoes, tomatoes and other valuable plants.

Animal world

The fauna of the northern Andes is part of the Brazilian zoogeographic region and is similar to the fauna of the adjacent plains.

The fauna of the Andes south of 5° south latitude belongs to the Chilean-Patagonian subregion. The Andean fauna in general is characterized by an abundance of endemic genera and species.

The Andes are inhabited by llamas and alpacas (representatives of these two species are used by the local population for wool and meat, and also as pack animals), prehensile-tailed monkeys, relict spectacled bear, pudú and gaemal deer (which are endemic to the Andes), vicuña, guanaco, Azar's fox , sloths, chinchillas, opossums, anteaters, degu rodents.

In the south - the blue fox, the Magellanic dog, the endemic rodent tuco-tuco, etc. There are many birds, among them hummingbirds, which are also found at altitudes above 4000 m, but are especially numerous and diverse in the “foggy forests” (tropical rainforests of Colombia, Ecuador , Peru, Bolivia and the extreme north-west of Argentina, located in the fog condensation zone); endemic condor, rising to a height of up to 7 thousand m; and others. Some species (such as chinchillas, which were intensively exterminated in the 19th - early 20th centuries for the sake of their skins; wingless grebes and the Titicaca whistler, found only near Lake Titicaca; etc.) are under threat of extinction.

A special feature of the Andes is the large species diversity of amphibians (over 900 species). Also in the Andes there are about 600 species of mammals (13% are endemic), over 1,700 species of birds (of which 33.6% are endemic) and about 400 species of freshwater fish (34.5% are endemic).

Ecology

One of the main environmental problems of the Andes is the deforestation, which is no longer renewed; The tropical rainforests of Colombia, which are being intensively reduced to plantations of cinchona, coffee, and rubber, have been particularly hard hit.

Possessing a developed agriculture, Andean countries face problems of soil degradation, soil contamination with chemicals, erosion, as well as desertification due to overgrazing (especially in Argentina).

Ecological problems coastal zones- pollution of sea water near ports and large cities (caused not least by the release of sewage waste and industrial waste into the ocean), uncontrolled fishing in large quantities.

As throughout the world, in the Andes there is an acute problem of greenhouse gas emissions into the atmosphere (mainly during electricity generation, as well as in ferrous metallurgy enterprises). Significant contribution to pollution environment Oil refineries, oil wells and mines also contribute (their activities lead to soil erosion and groundwater pollution; the activities of mines in Patagonia have had a detrimental effect on the biota of the area).

Due to a number of environmental problems, many species of animals and plants in the Andes are in danger of extinction.

Attractions

• Lake Titicaca;
• National Park Lauca;
• Chiloe National Park; to Cape Horn National Park;
• Santa Fe de Bogota: Catholic churches of the 16th-18th centuries, National Museum Colombia;
• Quito: Cathedral, Museum of Musical Instruments, Museo del Banco Central;
• Cusco: Cusco Cathedral, La Campaña Church, Haitun Rumiyoc Street (remains of Inca buildings);
• Lima: archaeological zones of Huaca Huallamarca and Huaca Pucllana, archbishop's palace, church and monastery of San Francisco;
• Archaeological complexes: Machu Picchu, Pachacamac, ruins of the city of Caral, Sacsayhuaman, Tambomachay, Pukapukara, Quenko, Pisac, Ollantaytambo, Moray, ruins of Pikilyakta.

• The capital of Bolivia, La Paz, is the highest capital in the world. It is located at an altitude of 3600 m above sea level.
• 200 km north of the city of Lima (Peru) are the ruins of the city of Caral - temples, amphitheaters, houses and pyramids. It is believed that Caral belonged to the oldest civilization in America and was built approximately 4000-4500 years ago. Archaeological excavations have shown that the city traded with large areas of the South American continent. It is especially interesting that archaeologists have not found any evidence of military conflicts for approximately a thousand years in the history of Caral.
• One of the most mysterious historical monuments in the world is the monumental archaeological complex of Sacsayhuaman, located northwest of Cusco, at an altitude of approximately 3,700 meters above sea level. The fortress of the same name in this complex is attributed to the Inca civilization. However, it has not yet been possible to establish how the stones of these walls, weighing up to 200 tons and fitted to each other with pinpoint precision, were processed. Also, the ancient system of underground passages has not yet been fully explored.
• The archaeological complex of Moray, located 74 kilometers from Cusco at an altitude of 3,500 meters, still arouses the admiration of not only archaeologists. Here, huge terraces, descending, form a kind of amphitheater. Research has shown that this structure was used by the Incas as an agricultural laboratory because different heights terraces made it possible to observe plants in different climatic conditions and experiment with them. Used here different soils and a complex irrigation system, the Incas grew 250 species of plants in total.

Inca Empire

The Inca Empire in the Andes is one of the most mysterious disappeared states. The tragic fate of a highly developed civilization, which appeared in far from favorable natural conditions and died at the hands of illiterate aliens, still worries humanity.

The era of the greats geographical discoveries(XV-XVII centuries) gave European adventurers the opportunity to quickly and fabulously get rich in new lands. Most often cruel and unprincipled, the conquistadors flocked to America not for the sake of scientific discoveries and cultural exchange between civilizations.

The fact that the papal throne recognized the Indians as spiritual beings in 1537 did not change anything in the methods of the conquistadors - they were not interested in theological disputes. By the time of the “humane” papal decision, the conquistador Francisco Pizarro had already managed to execute the Inca emperor Atahualpa (1533), defeat the Inca army and capture the capital of the empire, the city of Cusco (1536).

There is a version that at first the Indians mistook the Spaniards for gods. And it's quite possible that main reason this misconception is no longer White skin aliens, not that they rode on unprecedented animals, and not even that they possessed firearms. The Incas were amazed by the incredible cruelty of the conquistadors.

At the first meeting of Pizarro and Atahualpa, the Spaniards ambushed them, killed thousands of Indians and captured the emperor, who did not expect anything like this at all. After all, the Indians, whom the Spaniards condemned for human sacrifices, believed that human life- the highest gift, and that is why human sacrifice to the gods was the highest form of worship. But to just kill thousands of people who didn’t come for war at all?

There is no doubt that the Incas could offer serious resistance to the Spaniards. After the murder of the captive Atahualpa, for whom the Indians paid a monstrous ransom - almost 6 tons of gold, the conquistadors began to plunder the country, mercilessly melting down works of Incan jewelry into ingots. But Atahualpa’s brother Manco, who they appointed as the new emperor, instead of collecting gold for the invaders, fled and led the fight against the Spaniards. The Last Emperor, Tupac Amaru, Viceroy of Peru Francisco de Toledo was able to execute only in 1572, and even after that the leaders of new uprisings were called by his name.

Little has survived from the Inca civilization to the present day - after the death of hundreds of thousands of Indians, both at the hands of the Spaniards and from working in mines, famine, and European epidemics, there was no one to maintain the irrigation systems, high mountain roads, and beautiful buildings in order. The Spaniards destroyed a lot to get building material.

A country whose inhabitants were accustomed to supplies from public warehouses, in which there were no beggars and vagabonds, in long years after the arrival of the conquistadors it became a zone of human disaster.

Different theories place the age of the Andes mountain system from 18 million years to several hundred million years. But, more importantly for the people living in the Andes, the formation of these mountains is still ongoing.

Earthquakes, volcanic eruptions, and glacier collapses in the Andes do not stop. In 1835, Charles Darwin observed the eruption of the Osorno volcano from the island of Chiloe. The earthquake described by Darwin destroyed the cities of Concepción and Talcahuano and claimed numerous victims. Such events are not uncommon in the Andes.

So, in 1970, a glacier in Peru literally buried the city of Yungay with almost all its inhabitants in seconds, killing about 20,000 people. In 2010, an earthquake in Chile claimed several hundred lives, left millions homeless and caused enormous property damage. In general, serious disasters occur in the Andes with a frightening cyclicity - once every 10-15 years.

The Andean West subcontinent occupies the entire western part of the continent. It is the longest (9 thousand km) and one of the highest mountain systems on the mainland. The width of this mountain system reaches 500 km. In total, the Andes cover an area of ​​about 3,370,000 km². The Andes Mountains face a broad front towards, in the north, the Caribbean Sea. The eastern border with the countries of the Extra-Andean East runs along the foot of the Andean ridges. The unity of the physical-geographical countries of the subcontinent is due to the fact that they are located within the fold belt on the border of the lithospheric plates of the Pacific Ocean and South America.

A complex system of orotectonic zones of predominantly submeridional strike extends from the northern coast of the continent to. The different-aged ridges of the Coastal, Western and Eastern Cordillera stretch throughout the Andes mountain system. Mountain formation, especially active in the Paleogene and Neogene, continues to this day, accompanied by volcanic processes and earthquakes.

The region is also united by its position in the west of the continent, which limits the influence of the Pacific Ocean on the internal regions of the system and creates a contrast in the natural conditions of the western and eastern macroslopes.

The Andes are dominated by high-mountain relief, which determines the pronounced altitudinal zonation and the formation of significant modern glaciation. The huge extent from north to south determines a large difference in heat supply and moisture in individual parts of the system: the Andes mountains are located in several climatic zones, so the structure of altitudinal zones also differs. The orotectonic structure is also different.

Despite the mountainous nature of the subcontinent, its territory has long been quite densely populated. The peoples of the Andean countries developed basins, intermountain valleys and high plains within the Andes mountain system and adapted to life in these conditions. The Andes are home to the highest mountain cities, villages and cultivated lands.

Within the Andes, a number of physical and geographical countries are distinguished: Caribbean, Northern (Equatorial), Central (Tropical), Chilean-Argentine (Subtropical) and Southern (Patagonian) Andes. Tierra del Fuego has some special features - this region is either considered as a separate country or included in the Southern Andes.

Caribbean Andes Mountains

The Caribbean Andes Mountains are the northernmost part of the Andes Mountains and the only one where the ranges have a sublatitudinal trend. Here the Andes mountains stretch for 800 km along the northern coast of the Caribbean Sea from the river delta. Orinoco to the lowlands of Maracaibo. In the south, the region borders the Orinoco plains; in the west, the ridges of the Caribbean Andes are separated from the Cordillera de Merida in the Eastern Andes system by a tectonic valley occupied by one of the tributaries of the river. Apure. Unlike other parts of the Andean mountain system, the Caribbean Andes are formed within the Caribbean-Antilles folded region, which possibly represents the western part of the ancient Tethys Ocean and moved there as a result of the opening of the North Atlantic trench. The region is located on the border of the tropical and subequatorial zones in the zone of action of the northeastern trade winds. Its nature is significantly different from the rest of the Andes mountains. This is Venezuelan territory.

The country's topography, compared to other Andean regions, is simple in structure: these are young folded mountains, consisting of two parallel anticlinal ridges (Cordillera da Costa - Coast Range and Sierranía del Interior - Interior Ridge), separated by a synclinal longitudinal depression. It contains Lake Valencia, one of the few drainless lakes on the mainland.

Folded structures are broken by transverse and longitudinal faults, so the mountains are divided into blocks by tectonic and erosional valleys. Frequent earthquakes testify to the youth and incompleteness of mountain building, but there are no active ones here. The height of the Caribbean Andes does not reach 3000 meters. The highest point (2765 meters) is located in the Coastal Cordillera near Caracas, the capital of Venezuela.

The region is exposed to tropical air masses throughout the year, which enter here with the northeast trade wind. Only the southern slopes of the mountains fall under the influence of the equatorial monsoon in summer.

In winter, when the trade wind flow weakens somewhat and the southwest monsoon gives way to the winter northeast, a relatively dry period begins. Since precipitation is mainly orographic, its amount on the coast and leeward mountain slopes is small - 300-500 mm per year. Windward slopes receive up to 1000-1200 mm in the upper zones. The region has very small temperature amplitudes - 2-4°C. Caracas, located in a transverse valley at an altitude of 900-1000 meters, is called the city of “eternal spring”.

The Andes Mountains are cut by numerous deeply incised valleys of short, wild rivers that carry masses of debris onto the coastal plain, especially during the rainy season in summer. There are karst areas, practically devoid of surface water.

The region is dominated by xerophytic vegetation. At the foot of the mountains and in the lower belt, monte formations (mesquite bush, cacti, milkweed, prickly pear, etc.) are common. On the low-lying coast, mangroves along the shores of lagoons are common. On the mountain slopes above 900-1000 meters, sparse mixed forests of evergreen, deciduous and coniferous trees grow. In some places they are replaced by xerophytic shrub thickets such as chaparral. Palm groves stand out as bright spots. Higher up are meadows, often covered with shrubs. The upper limit of forests is artificially reduced, since meadows are used as pastures, and in the border part of forests, under conditions extreme for woody vegetation, it gradually disappears and is not restored.

The coastal strip and intermountain troughs of the Caribbean Andes are oil-bearing. The entire Caribbean coast with sandy beaches, a hot, dry climate with stable weather conditions is an excellent resort area. Coffee, cocoa, cotton, sisal, tobacco, etc. are grown on the gentle slopes of the mountains and in the valleys. Cattle are grazed in the mountain meadows.

This part of Venezuela is quite densely populated. In the Caracas area, the population density is over 200 people/km 2 . Here are located big cities and ports. Nature has been significantly modified by various human activities: flat areas and more or less gentle slopes have been plowed, forests have been destroyed, and the coastline has been transformed. A network of national parks has been created here, used to protect landscapes and for tourism.

Northern Andes Mountains

This is the northernmost part of the Andean system proper, extending from the Caribbean coast to 4-5° S. w. The eastern border with the Orinoco plains runs along the foot of the Andes mountains, and the southern border follows transverse tectonic faults. The border is located approximately in the same area climatic zones- tropical and equatorial with sharp differences in moisture conditions and altitudinal structure on the slopes of western exposure. The region includes the western regions of Venezuela, Colombia and Ecuador. The lower belts of the western mountain slopes and coastal plains are characterized by a humid, hot, equatorial climate. But even in areas with subequatorial climatic conditions, at some altitude above sea level, constantly moist forests - hyleas - grow, which is why the Northern Andes Mountains are called Equatorial.

The Andes Mountains within the region consist of several ranges separated by deep depressions. The northern part of the country has a particularly complex structure.

Along the Pacific Ocean stretches a narrow, low, highly dissected Coastal Cordillera, separated from the neighboring zone (Western Cordillera) by the tectonic valley of the river. Atrato. The Western Cordillera begins at the Gulf of Darien and extends to the borders of the region. The Eastern Cordillera branches within the Northern Andes: at about 3° N. w. it is divided into Central with the Sierra Nevada de Santa Marta massif (up to 5800 meters high) in the north and Eastern, which, in turn, with two branches (Sierra Perija and Cordillera de Merida) covers a vast depression with a lagoon Maracaibo. The graben-shaped valley between the Western and Central Cordilleras is occupied by the river. Which one, and between the Central and Eastern - the river. Magdalena. The entire mountainous region is 400-450 km wide. South of 3° N. w. The Western and Eastern Cordilleras are moving closer together, and within Ecuador the system narrows to 100 km. Between the mountain ranges there is a zone of powerful faults. The main peaks of the ridges are, as a rule, extinct and active volcanoes(Cotopaxi, Chimborazo, Sangay, etc.), covered with snow and ice. The area is also characterized by high seismicity. The epicenters of earthquakes are usually confined to the faults of the intermountain depression.

The region has a hot, constantly humid climate. The slopes of the Andes mountains facing the Pacific Ocean receive 8,000-10,000 mm per year.

Unstablely stratified, formed over the warm currents of the equatorial latitudes of the ocean, dominates here throughout the year. Rising along the slopes of the ridges, it gives off moisture in the form of heavy rains. The eastern slopes are influenced by the monsoon circulation, but orographic precipitation also falls here in winter, although the annual amounts are slightly less - up to 3000 mm. Even the interior regions are not particularly arid. A short dry period in winter occurs only in the northeast of the region.

In the Northern Andes Mountains the system of altitudinal zones is most clearly and fully expressed.

The lower zone is tierra caliente (“hot land”) with constantly high temperatures(27-29°C) and a large amount of precipitation is occupied by hylaea, which are almost no different from the Amazonian jungle. Due to unfavorable conditions for humans, the belt is sparsely populated. Only in some places at the foot of the mountains are forests cleared for sugarcane and banana plantations. Above 1000-1500 m, the tierra templada (“temperate land”) begins. It is cooler here (16-22°C), precipitation up to 3000 mm on windward slopes and 1000-1200 mm on leeward slopes. This is a belt of evergreen mountain hylea or deciduous evergreen forests with the best living conditions. It is quite densely populated. Lives here most of population of the Northern Andes Mountains, there are large cities, for example the capital of Ecuador - Quito. More or less gentle slopes are plowed, coffee trees, corn, tobacco, etc. are grown. The belt is called the “coffee” belt or the “eternal spring” belt. Above 2000-2800 meters there is tierra fria (“cold land”). Average monthly temperatures here are 10-15°C. It is at these heights that orographic structures are constantly formed, therefore the high-mountain hylea of ​​low-growing evergreen trees (oaks, myrtle, some conifers) with an abundance of ferns, bamboos, mosses, mosses, and lichens is called nephelogeia (“foggy forest”). There are many vines and epiphytes in it. Cool weather with constant fog and drizzling rain is unfavorable for life. Few Indian tribes They live in hollows where they grow corn, wheat, potatoes, legumes, and engage in livestock breeding. At an altitude of 3000-3500 meters, Tierra Helada (“frosty land”) begins. Average monthly temperatures in this zone are only 5-6°C, daily amplitudes are more than 10°C, all year round There may be night frosts and snowfalls. In the subnival zone, the vegetation of mountain meadows (paramos) is formed from grasses (bearded grass, feather grass), low-growing shrubs and tall (up to 5 meters) heavily pubescent Asteraceae with bright flowers. In the periglacial zone, rocky placers are common, sometimes covered with mosses and lichens. The nival belt begins at an altitude of 4500-4800 meters.

Among the natural resources of the Northern Andes Mountains are large oil reserves in the depressions. The oil and gas basin of the Maracaibo depression, where there are several dozen large fields, and the tectonic Magdalena Valley are especially rich. In the river valley The Kaukas mine hard coal and, on the Pacific coast, placer gold and platinum. There are also known deposits of iron, nickel, molybdenum, copper ores and silver in mountainous areas. Emeralds are mined near Bogota. The region also has good agroclimatic conditions allowing for the cultivation of tropical crops. There are many valuable tree species in the mountain gilya, including cinchona, kola, balsa with light, non-rotting wood. Long sea voyages were once carried out on balsa rafts. In our time, Thor Heyerdahl's expedition traveled several thousand kilometers on such a raft across the Pacific Ocean.

The intermountain valleys and basins of the Northern Andes Mountains at altitudes of 1000-3000 meters are densely populated and developed. Fertile soils are plowed. Large cities are located in graben valleys and basins, including the capitals of Ecuador (Quito - at an altitude of about 3000 meters) and Colombia (Bogota - at an altitude of about 2500 meters). The nature of the valleys, basins and mountain slopes of the Tierra Templada belt with conditions favorable for humans has been greatly changed. In the 60-70s. XX century In Ecuador and Colombia, reserves and national parks were created to protect and study natural landscapes.

Central Andes Mountains

The Central Andes Mountains are the largest of the Andean physiographic countries. It starts south of 3° S. w. The mountain system here is expanding; between the chains of the Western and Eastern Cordillera there are high-mountain plains in the middle massif. The total width of the mountain region reaches 800 km. The southern border is drawn approximately at 27-28° S. sh., where the Eastern Cordillera pinches out, and the tropical climate characteristic of the Central Andes Mountains gives way to subtropical. The region contains mountainous parts of Peru, Bolivia, northern Chile and northwestern Argentina.

The orotectonic structure is distinguished by the presence of high mountain (3000-4500 meters) plateaus and plateaus - Puna (in Bolivia they are called Altiplano). The rigid middle mass, within which these plains were formed, is divided into blocks; magma rises along cracks and lavas flow out.

As a result, areas of peneplain, accumulative plains in relief depressions, and lava plateaus with volcanoes are combined here. From the west, the plains are limited by high young folded chains of the Western Cordillera with a large number of. In the east, the ridges of the Eastern Cordillera rise on Mesozoic and Paleozoic folded structures, many of whose peaks above 6000 meters are covered with caps of glaciers and snow. In the south (within Chile), the low Coastal Cordillera rises along the coast, separated from the Western depression. One of them is the Atacama Desert.

The climate in most of the Central Andes is arid. The coastal part of the region is dominated by the extremely arid and cool tropical climate of the western coasts of the continents (the climate of coastal, “wet” or “cold” deserts, as it is often called). At 20° south w. the average of the warmest months is 18-21°C, the annual range is 5-6°C. A flow of cold air from the south passes far north over the Peruvian Current, lowering summer temperatures. There is very little precipitation. Within the Central Andes Mountains, this climatic region has the greatest extent from north to south (from 3° to 28°S) and rises high along the mountain slopes of western exposure.

The largest areas in the region are occupied by high-mountain arid climates with desert and semi-desert landscapes.

Average temperatures in the summer months in the Central Andean high plains are 14-15°C, during the day they can rise to 20-22°C and at night drop to negative values. This is explained by the rarefaction and transparency of mountain air. In winter, average monthly temperatures are positive, but a large diurnal amplitude remains, and at night there are frosts down to -20°C. Has some moderating effect large lake Titicaca. Not far from it is La Paz - the capital of Bolivia - the highest capital in the world (3700 metro). The amount of precipitation in Pune is small and increases from west to east - from 250 mm to 500-800 mm. The windward slopes of the Eastern Cordillera receive up to 2000 mm due to the influence of.

The soil and vegetation cover of the Central Andes is formed according to the distribution of precipitation and temperature conditions.

In coastal deserts, plants adapt to the rainless regime and obtain moisture from dew and fog. Rare xerophytic shrubs and cacti make up the sparse vegetation cover. Characteristic are peculiar bromeliads with hard gray leaves And weak roots and lichens. In some places there is no vegetation; moving sands with dune and hilly relief are common. Where the annual amount of precipitation (in the form of fog) reaches 200-300 mm. Lomas plant formations appear, represented by ephemerals and a few perennial herbs and cacti. Lomas come to life in winter, when evaporation decreases, and dry out in summer. The interior plains are dominated by puna, a steppe dominated by fescue, reed grass, other poppies, and occasional low-growing shrubs and trees, such as the thorny bromeliad puya and kenoa, growing along the valleys. In western arid regions, they are common with hard grasses, tola shrubs, cushion-shaped llareta plants, and cacti. In saline areas, of which there are many, wormwood and ephedra grow. On the eastern slopes there is a pronounced altitudinal zonation, characteristic of the humid regions of the Andes mountains. Even where the lower belt of mountains is adjacent to the dry savannas of the Gran Chaco, higher up, at the level of formation of orographic clouds, wet mountain hylaea of ​​the Tierra Templada belt appear, giving way to formations of the Tierra Fria and Tierra Helada belts.

The fauna of the Central Andes Mountains is interesting and unusual, rich in endemic species.

Among the ungulates - guanaco and vicuña, which have almost disappeared at present, and the Peruvian deer. There are many rodents (viscacha, chinchilla, acodon, etc.), birds (from tiny hummingbirds in the Lomas formation to giant predatory condors). Many animals, including birds, live in burrows, like the inhabitants of the highlands of Tibet.

The subtropical climate of the Pacific coast and the adjacent mountain slopes is distinguished by well-defined Mediterranean-type features: dry summers and rainy winters with average monthly positive temperatures. As you move away from the ocean, the degree of continentality increases and the climate becomes drier.

On the western slopes of the Cordillera Main there is more precipitation, the eastern slopes facing the Pampian Sierras and the Dry Pampa are quite dry. On the coast, seasonal temperature amplitudes are small (7-8°C); in the Longitudinal Valley, temperature fluctuations are greater (12-13°C). The regime and amount of precipitation change from north to south. On the border with tropical climatic regions, the climate is extremely dry - 100-150 mm per year, and in the south, where the influence of the South Pacific baric maximum weakens and the westerly transport of temperate latitudes intensifies, the annual precipitation reaches 1200 mm with a uniform regime.

The nature of surface runoff is also different and varies both from west to east and from north to south. In the northern regions of the country, river flows are mostly periodic. In the central part there is a fairly dense network of rivers with two rises of water - in winter, when it rains, and in summer, when snow and ice melt in the mountains. The river network is especially dense in the south of the region. The rivers here are full-flowing all year round, and maximum flow occurs in winter. Sometimes they give rise to rivers. In the south, at the foot of the Main Cordillera, there are terminal lakes dammed by lavas or moraines.

Natural vegetation in the region is poorly preserved. Beneath Mediterranean-type formations similar to maquis or chaparral, brown soils have developed that are suitable for growing subtropical crops, so wherever possible the land is ploughed. Even more fertile dark-colored chernozem-like soils are developed in the Longitudinal Valley on volcanic rocks. These lands are occupied by agricultural crops.

Only on mountain slopes that are inconvenient for plowing are thickets of evergreen xerophytic shrubs - espinal - preserved. On the Main Cordillera, up the slopes, they are replaced by deciduous and mixed forests, where teak, litra, perel, canelo, nothofagus, honey palm, etc. grow. Above the forests (from an altitude of 2500 meters), a belt of mountain meadows begins, within which ordinary and for the alpine meadows of the Old World, buttercups, saxifrage, primroses, etc. On the arid eastern slope, forests are practically absent. Semi-desert landscapes are also typical for the northern part of the region, including the north of the Longitudinal Valley. In the extreme south, hemihyleas appear with a predominance of evergreen noto-fagus on brown forest soils. In the forest belt of volcanic massifs there are many plants brought from other areas of the world. Artificial tree plantations surround villages and fields.

Land and agroclimatic resources- the main natural resources of the Chilean-Argentine Andes. They allow you to grow here crops common to the Mediterranean (grapes, citrus fruits, olives, etc.). There are vast fields of wheat and corn. In the Longitudinal Valley, where the capital of Chile, Santiago, is located, half the country’s population lives (the population density here reaches 180 people/km2), despite the fact that this is a seismic area where strong earthquakes. Nature here has been changed to the greatest extent. In Chile and Argentina there are national parks and natural reserves created to protect mountain and lakeside landscapes and the remaining natural flora and fauna.

Southern (Patagonian) Andes Mountains

This is the southern part of the Andean system, bordering on the east with.

South of 42° S. w. The Andes mountains are declining. The coastal Cordillera passes to the islands of the Chilean archipelago, a longitudinal tectonic depression forms bays and straits along the coast. The territory of the Patagonian Andes, like the Chilean-Argentine Andes, belongs to Chile and Argentina. Mountain-building processes in the region are still ongoing, as evidenced by modern active volcanism. The main (Patagonian) Cordillera is low (up to 2000-2500 meters, rarely above 3000 meters) and highly fragmented.

It is a chain of separate massifs, within which glacial morphosculpture is widely developed. Unusual type for South America coastline- These are fjords of glacial-tectonic origin. There are many extinct and active volcanoes in the Patagonian Cordillera.

The region is located in temperate latitudes. In the west, the climate is maritime with heavy rainfall (up to 6000 mm per year). The eastern slopes of the mountains also receive large amounts of precipitation. People penetrate here from the Pacific Ocean along the vast depressions separating the mountain ranges.

Average monthly temperatures on the coast in winter are 4-7°C, in summer - 10-15°C. In the mountains, already at an altitude of 1200 meters, temperatures in the summer months drop to negative values. The snow line lies very low: in the south of the region it descends to 650 meters.

The Patagonian Andes are characterized by a large area of ​​modern glaciation - more than 20,000 km 2 (out of 33,000 km 2 for the entire Andes). The humid climate and low temperatures in the mountains contribute to the development of mountain-cover type glaciers.

The Northern and Southern glacial plateaus form continuous glacial fields that overlap intermountain depressions. Outlet glaciers on the western slopes descend in places to ocean level, producing icebergs. On the eastern slopes there is mountain-type glaciation, and the glacial tongues end in lakes located at the foot of the mountains at an altitude of 180-200 meters above sea level. Mountain ranges and nunataks rise above the ice sheets, dividing them into separate fields. It is believed that the weight of huge masses of ice contributes to the general decline of the region's surface. Indirect confirmation of this is the fact that there is a similar decrease in heights and a similar structure of the coastline in those regions of the Cordillera North America, which are located in abundantly moist latitudes of the temperate zone and carry large masses of ice.

Glaciers and heavy rainfall feed many deep rivers. Their valleys cut deeply into the surface, increasing the ruggedness of the mountainous terrain. Natural features unique to South America include the abundance of lakes, of which there are few on the mainland. In the Southern Andes there are many small and several large glacial lakes, formed mainly as a result of moraines damming river flows.

The slopes of the Southern Andes are covered with forests.

In the north, where it is warmer, the lower parts of the slopes up to a height of 500-600 meters are covered with moist evergreen subtropical forests with lianas and epiphytes. In them, along with teak wood, canelo, Perseus, nothofagus, etc., bamboo and tree ferns grow. Higher up, dominance passes to nothophagus, sometimes forming pure dark stands without undergrowth or groves with an admixture of conifers (podocarpus, Fitzroy and other types of Antarctic flora). Even higher rise crooked forests of deciduous nothofagus and mountain meadows, often swampy. To the south, the vegetation gives way to Magellan subantarctic forests of nothophagus with an admixture of some conifers. Similar forests grow on the eastern slopes of the Southern Andes. At the foot of the mountains they give way to shrubs and steppes characteristic of the Patagonian Plateau.

The main natural resources of the Patagonian Andes are hydroelectric resources and forests. Natural resources are used insignificantly. This contributes to the good preservation of the natural landscapes of this part of the Andes. On the territory of Chile and Argentina there are several national parks where mountain, lake, glacial landscapes, fjord coasts, forests of nothofagus, Fitzroyas, etc., endangered species of animals (pudu deer, chinchilla, viscacha, guanaco, Pampas cat, etc.) are protected .).

Tierra del Fuego

It is an island physical-geographical country on the southern edge of the mainland, separated from it by the narrow, winding Strait of Magellan. The archipelago consists of dozens of large and small islands with a total area of ​​more than 70 thousand km 2. The largest one is Fr. Tierra del Fuego, or the Big Island, occupies almost 2/3 of the archipelago's area. The islands belong to Chile and Argentina.

The western part of the region is a continuation of the Andes mountain system. In many natural features - geological structure and relief, the nature of the coastline, modern glaciation, mountain vegetation, etc., this part of the archipelago is similar to the Southern Andes. In the east of the Big Island, the rolling plains are an extension of the Patagonian Plateau.

The western part of the archipelago is highly dissected. Many mountain ranges up to 1000-1300 meters high are separated by intermountain valleys, often flooded with ocean waters - fjords and straits. The highest point of the mountains (2469 meters) is located on the Big Island. Ancient and modern glacial relief dominates. There are many lakes dammed by moraines.

The climate is temperate maritime. Humidity changes from west to east.

The western part of the region receives heavy rainfall (up to 3000 mm) throughout the year, mainly in the form of drizzle. There are up to 300-330 rainy days a year. In the eastern part, washed by the cold Falkland Current, precipitation is much less (up to 500 mm).

Summers are cool, average monthly temperatures are 8-10°C, winters are relatively warm (1-5°C). They say that summer here is like in the tundra, and winter (in terms of temperatures) is like in the subtropics. As you rise into the mountains, temperatures quickly decrease, and already from an altitude of 500 m negative values ​​predominate.

The humid climate and relatively low temperatures contribute to the development of glaciation. The snow line in the west lies at an altitude of about 500 m. The outlet glaciers reach sea level, and icebergs break off from them.

The border of the forests covering the western slopes of the mountains sometimes reaches almost to the snow line. The forests are of the same composition as in the Southern Andes. They are dominated by nothophagus, canelo (from the magnolia family), and some conifers. In places above the forest belt, and in the east and on the plains, subantarctic meadows with peat bogs, reminiscent of tundra, are common.

The fauna is similar to the Southern Andes (guanacos, Magellanic dogs, rodents, including burrowing tuco-tucos, also living in Patagonia). The southernmost islands of the archipelago are inhabited by birds, and among mammals only a few species of bats and one species of rodent live there. One of the islands ends at Cape Horn - the southern tip of the entire mainland.

Found on Tierra del Fuego, but the main occupation of the population who have long inhabited the east of the region is sheep breeding. Despite the winter lack of food, sheep provide good income. The pastures here are richer than on the Patagonian Plateau. In some places they are degrading due to the destruction of natural vegetation. Several national parks have been created on the islands.