Argentina has long played an important role in the continent’s history. Following three centuries of Spanish colonization, Argentina declared independence in 1816, and Argentine nationalists were instrumental in revolutionary movements elsewhere, a fact that prompted 20th-century writer Jorge Luis Borges to observe, “South America’s independence was, to a great extent, an Argentine enterprise.” Torn by strife and occasional war between political factions demanding either central authority (based in Buenos Aires) or provincial autonomy, Argentina tended toward periods of caudillo, or strongman, leadership, most famously under the presidency of Juan Perón. The 1970s ushered in a period of military dictatorship and repression during which thousands of presumed dissidents were “disappeared,” or murdered; this ended in the disastrous Falklands Islands War of 1982, when Argentina invaded the South Atlantic islands it claimed as its own and was defeated by British forces in a short but bloody campaign. Defeat led to the fall of the military regime and the reestablishment of democratic rule, which has since endured despite various economic crises.
The country’s name comes from the Latin word for silver, argentum, and Argentina is indeed a great source of valuable minerals. More important, however, has been Argentina’s production of livestock and cereals, for which it once ranked among the world’s wealthiest nations. Much of this agricultural activity is set in the Pampas, rich grasslands that were once the domain of nomadic Native Americans, followed by rough-riding gauchos, who were in turn forever enshrined in the nation’s romantic literature. As Borges describes them in his story The South, the Pampas stretch endlessly to the horizon, dwarfing the humans within them; traveling from the capital toward Patagonia, the story’s protagonist, Señor Dahlmann, “saw horsemen along dirt roads; he saw gullies and lagoons and ranches; he saw long luminous clouds that resembled marble; and all these things were casual, like dreams of the plain.... The elemental earth was not perturbed either by settlements or other signs of humanity. The country was vast, but at the same time it was intimate and, in some measure, secret. The limitless country sometimes contained only a solitary bull. The solitude was perfect and perhaps hostile, and it might have occurred to Dahlmann that he was traveling into the past and not merely south.”
Despite the romantic lure of the Pampas and of vast, arid Patagonian landscapes, Argentina is a largely urban country. Buenos Aires, the national capital, has sprawled across the eastern Pampas with its ring of modern, bustling suburbs. It is among South America’s most cosmopolitan and crowded cities and is often likened to Paris or Rome for its architectural styles and lively nightlife. Its industries have drawn colonists from Italy, Spain, and numerous other countries, millions of whom immigrated in the late 19th and early 20th centuries. Greater Buenos Aires is home to about one-third of the Argentine people. Among the country’s other major cities are Mar del Plata, La Plata, and Bahía Blanca on the Atlantic coast and Rosario, San Miguel de Tucumán, Córdoba, and Neuquén in the interior.
- Land
Argentina is shaped like an inverted triangle with its base at the top; it is some 880 miles (1,420 km) across at its widest from east to west and stretches 2,360 miles (3,800 km) from the subtropical north to the subantarctic south. The country is bounded by Chile to the south and west, Bolivia and Paraguay to the north, and Brazil, Uruguay, and the Atlantic Ocean to the east. Its undulating Atlantic coastline stretches some 2,900 miles (4,700 km).
Argentina’s varied geography can be grouped into four major regions: the Andes, the North, the Pampas, and Patagonia. The Andean region extends some 2,300 miles (3,700 km) along the western edge of the country from Bolivia to southern Patagonia, forming most of the natural boundary with Chile. It is commonly subdivided into two parts: the Northwest and the Patagonian Andes, the latter of which is discussed below under Patagonia. The North is commonly described in terms of its two main divisions: the Gran Chaco, or Chaco, comprising the dry lowlands between the Andes and the Paraná River; and Mesopotamia, an area between the Paraná and Uruguay rivers. The centrally located plains, or Pampas, are grasslands subdivided into arid western and more humid eastern parts called, respectively, the Dry Pampa and the Humid Pampa. Patagonia is the cold, parched, windy region that extends some 1,200 miles (1,900 km) south of the Pampas, from the Colorado River to Tierra del Fuego.
Relief
- The Northwest
This part of the Andes region includes the northern half of the main mountain mass in Argentina and the transitional terrain, or piedmont, merging with the eastern lowlands. The region’s southern border is the upper Colorado River. Within the region the Andean system of north-south–trending mountain ranges varies in elevation from 16,000 to 22,000 feet (4,900 to 6,700 metres) and is interrupted by high plateaus (punas) and basins ranging in elevation from about 10,000 to 13,400 feet (3,000 to 4,080 metres). The mountains gradually decrease in size and elevation southward from Bolivia. South America’s highest mountain, Aconcagua (22,831 feet [6,959 metres]), lies in the Northwest, together with a number of other peaks that reach over 21,000 feet (6,400 metres). Some of these mountains are volcanic in origin.
To the southeast, where the parallel to subparallel ranges become lower and form isolated, compact units trending north-south, the flat valleys between are called bolsones (basins). This southeastern section of the Northwest is often called the Pampean Sierras, a complex that has been compared to the Basin and Range region of the western United States. It is characterized by west-facing escarpments and gentler east-facing backslopes, particularly those of the spectacular Sierra de Córdoba. The Pampean Sierras have variable elevations, beginning at 2,300 feet (700 metres) in the Sierra de Mogotes in the east and rising to 20,500 feet (6,250 metres) in the Sierra de Famatina in the west.
- The Gran Chaco
The western sector of the North region, the Gran Chaco, extends beyond the international border at the Pilcomayo River into Paraguay, where it is called the Chaco Boreal (“Northern Chaco”) by Argentines. The Argentine sector between the Pilcomayo River and the Bermejo River is known as the Chaco Central. Argentines have named the area southward to latitude 30° S, where the Pampas begin, the Chaco Austral (“Southern Chaco”). The Gran Chaco in Argentina descends in flat steps from west to east, but it is poorly drained and has such a challenging combination of physical conditions that it remains one of the least-inhabited parts of the country. It has a subtropical climate characterized by some of Latin America’s hottest weather, is largely covered by thorny vegetation, and is subject to summer flooding.
- Mesopotamia
East of the Gran Chaco, in a narrow depression 60 to 180 miles (100 to 300 km) wide, lies Mesopotamia, which is bordered to the north by the highlands of southern Brazil. The narrow lowland stretches for 1,000 miles (1,600 km) southward, finally merging with the Pampas south of the Río de la Plata. Its designation as Mesopotamia (Greek: “Between the Rivers”) reflects the fact that its western and eastern borders are two of the region’s major rivers, the Paraná and the Uruguay. The northeastern part, Misiones province, between the Alto (“Upper”) Paraná and Uruguay rivers, is higher in elevation than the rest of Mesopotamia, but there are several small hills in the southern part.
- The Pampas
Pampa is a Quechua Indian term meaning “flat plain.” As such, it is widely used in southeastern South America from Uruguay, where grass-covered plains commence south of the Brazilian Highlands, to Argentina. In Argentina the Pampas broaden out west of the Río de la Plata to meet the Andean forelands, blending imperceptibly to the north with the Chaco Austral and southern Mesopotamia and extending southward to the Colorado River. The eastern boundary is the Atlantic coast.
The largely flat surface of the Pampas is composed of thick deposits of loess interrupted only by occasional caps of alluvium and volcanic ash. In the southern Pampas the landscape rises gradually to meet the foothills of sierras formed from old sediments and crystalline rocks.
This region consists of an Andean zone (also called Western Patagonia) and the main Patagonian plateau south of the Pampas, which extends to the tip of South America. The surface of Patagonia descends east of the Andes in a series of broad, flat steps extending to the Atlantic coast. Evidently, the region’s gigantic landforms and coastal terraces were created by the same tectonic forces that formed the Andes, and the coastline is cuffed along its entire length as a result. The cliffs are rather low in the north but rise in the south, where they reach heights of more than 150 feet (45 metres). The landscape is cut by eastward-flowing rivers some of them of glacial origin in the Andes that have created both broad valleys and steep-walled canyons.
Patagonia includes a region called the Lake District, which is nestled within a series of basins between the Patagonian Andes and the plateau. There are volcanic hills in the central plateau west of the city of Río Gallegos. These hills and the accompanying lava fields have dark soils spotted with lighter-coloured bunchgrass, which creates a leopard-skin effect that intensifies the desolate, windswept appearance of the Patagonian landscape. A peculiar type of rounded gravel called grava patagónica lies on level landforms, including isolated mesas. Glacial ice in the past extended beyond the Andes only in the extreme south, where there are now large moraines.
- Drainage
The largest river basin in the area is that of the Paraguay–Paraná–Río de la Plata system. It drains an area of some 1.2 million square miles (3.2 million square km), which includes northern Argentina, the whole of Paraguay, eastern Bolivia, most of Uruguay, and a large part of Brazil. In Argentina the principal river of this system is the Paraná, formed by the confluence of the Paraguay and Alto Paraná rivers. The Río de la Plata (often called the River Plate) is actually the estuary outlet of the system formed by the confluence of the Paraná and Uruguay rivers; its name, meaning “River of Silver,” was coined in colonial times before explorers found that there was neither a single river nor silver upstream from its mouth. Other tributaries of this system are the Iguazú (Iguaçu), Pilcomayo, Bermejo, Salado, and Carcarañá. Just above its confluence with the Alto Paraná, the Iguazú River plunges over the escarpment of the Brazilian massif, creating Iguazú Falls—one of the world’s most spectacular natural attractions.
Aside from the Paraná’s main tributaries, there are few major rivers in Argentina. Wide rivers flow across the Gran Chaco flatlands, but their shallow nature rarely permits navigation, and never with regularity. Moreover, long-lasting summer floods cover vast areas and leave behind ephemeral swamplands. During winter most rivers and wetlands of the Gran Chaco dry up, the air chills, and the land seems visibly to shrink. Only three of the region’s numerous rivers—the Pilcomayo, Bermejo, and Salado—manage to flow from the Andes to the Paraguay-Paraná system in the east without evaporating en route and forming salt pans (salinas). The region’s largest rivers follow a veritable maze of courses during flood season, however.
In the Northwest the Desaguadero River and its tributaries in the Andes Mountains water the sandy deserts of Mendoza province. The principal tributaries are the Jáchal, Zanjón, San Juan, Mendoza, Tunuyán, and Diamante. In the northern Pampas, Lake Mar Chiquita, the largest lake in Argentina, receives the waters of the Dulce, Primero, and Segundo rivers but has no outlet. Its name, meaning “Little Sea,” refers to the high salt content of its waters.
Rivers that cross Patagonia from west to east diminish in volume as they travel through the arid land. The Colorado and Negro rivers, the largest in the south-central part of the country, produce major floods after seasonal snow and ice melt in the Andes. Farther south the Santa Cruz River flows eastward out of the glacial Lake Argentino in the Andean foothills before reaching the Atlantic.
- Soils
Soil types in Argentina range from the light-coloured saline formations of the high puna in the Northwest to the dark, humus-rich type found in the Pampas. Golden-brown loess soils of the Gran Chaco are sometimes lighter where salinity is excessive but turn darker toward the east in the Mesopotamian border zone. These give way to soils ranging from rust to deep red colorations in Misiones. Thick, dark soils predominate in the fertile loess grasslands of the Pampas, but lighter brown soils are common in the drier parts of northern Patagonia. Light tan arid soils of varying texture cover the rest of this region. Grayish podzolic types and dark brown forest soils characterize the Andean slopes.
- Climate
Argentina lies almost entirely within the temperate zone of the Southern Hemisphere, unlike the rest of the continent to the north, which lies within the tropics. Tropical air masses only occasionally invade the provinces of Formosa and Misiones in the extreme north. The southern extremes of Argentina, which extend to latitude 55° S, also have predominantly temperate conditions, rather than the cold continental climate of comparable latitudes in North America. The South American landmass narrows so markedly toward its southern tip that weather patterns are moderated by the Pacific and Atlantic oceans, and average monthly temperatures remain above freezing in the winter. The temperate climate is interrupted by a long, narrow north-south band of semiarid to arid conditions and by tundra and polar conditions in the high Andes and in southern portions of Tierra del Fuego.
Precipitation is moderate to light throughout most of the country, with the driest areas in the far northwest and in the southern part of Patagonia. Most rainfall occurs in the northeast, in the Humid Pampa, Mesopotamia, and the eastern Chaco. Windstorms (pamperos) with thunder, lightning, and hail are common. During winter, stationary fronts bring long rainy periods. Dull, gray days and damp weather characterize this season, especially in the Pampas. Between winter storms, tropical air masses make incursions southward and bring mild relief from the damp cold.
- Andean and sub-Andean zones
Some parts of the Andean Northwest region have an annual average temperature range of more than 36 °F (20 °C), and occasional continental climatic conditions occur. Winter temperatures sometimes fall below freezing on cloudless days and nights.
The high-elevation, cold climatic phenomenon in Argentina is sometimes referred to as tundra climate and, in even colder mountaintop areas, as polar. Generally, the tundra climate occupies the mountain zones where average annual temperatures are below 50 °F (10 °C); in the north this occurs above 11,500 feet (3,500 metres). Moving southward, tundra climate occurs at gradually decreasing elevations until it reaches sea level in southern Tierra del Fuego. The highest Andean peaks have permanent snow and ice cover.
- The rain shadow zone
Argentina is the only place in the Southern Hemisphere with an extensive portion of arid eastern coastline. This is caused by a longitudinal rain shadow zone (created when air masses lose their moisture while passing over high mountains) on the eastern side of the Andes. The zone begins in the Andean Northwest and extends along the eastern slopes of the Andes southward to, but not including, Tierra del Fuego. The rain shadow area has a central arid (desert) core rimmed by semiarid, or steppe, conditions. The steppe areas have about twice the annual precipitation found in the arid zones, but evaporation exceeds precipitation in both zones, which therefore remain treeless. Most of the arid region is subjected to strong winds that carry abrasive sand and dust. This is particularly true in Patagonia, where windblown dust creates a continuous haze that considerably reduces visibility.
- The Pampean zone
The Pampas occupy a transitional area between high summer temperatures to the north and cooler summers to the south. Buenos Aires, located on the northern edge of the Pampas, has a climate similar to that of cities in the southeastern United States, with hot, humid summers and cool, mild winters. The range of mean temperatures for summer months (December to February) is about 72–75 °F (22–24 °C), whereas that for winter months (June to August) is about 46–55 °F (8–13 °C). In the Humid Pampa the rainfall varies from 39 inches (990 mm) in the east to 20 inches (500 mm) in areas near the Andes—about the minimum needed for nonirrigated crops. Cold fronts that move northward from Patagonia, chiefly in July, bring occasional frosts and snow to the Pampas and Mesopotamia. In rare instances a dusting of snow covers Buenos Aires itself.
- Plant and animal life
Argentina’s fauna and flora vary widely from the country’s mountainous zones to its dry and humid plains and its subpolar regions. In heavily settled regions the makeup of plant and animal life has been profoundly modified.
- The Northwest
Vegetation in the Northwest region includes that of the high puna desert, the forested slopes of the Andes, and the subtropical scrub forests of the Pampean Sierras, the latter merging with the deciduous scrub woodlands of the Gran Chaco. Vegetation on the mostly exposed soil of the puna consists of dwarf shrubs and tough grasses, notably bunchgrass; these and other plants in the region are coloured almost as brown as the ground itself. The region is the land of the guanaco and its near relatives, the llama, alpaca, and vicuña.
Forests grow along the eastern border of the puna region southward to the colder Andean zones, covering many slopes in this part of the mountains. The so-called mistol (jujube) forest thrives above 1,650 feet (500 metres), although giant cedars and some other tree species disappear above 3,300 feet (1,000 metres). A subtropical rainforest, composed of laurels, cedars, and other species, is found at elevations of about 4,000 feet (1,200 metres). The tree heights diminish above 7,000 feet (2,100 metres), and the growth becomes more like that of a cloud forest, with myrtles and laurels predominating. Higher still grow the queñoa, small, crooked trees that in places extend to the timberline at 11,500 feet (3,500 metres).
Southeast of the Andean region described above, xerophytic (drought-tolerant) scrub forests, called monte, and intervening grasslands spread across the Pampean Sierras. Vegetation includes species of mimosa and acacia, and there is a smattering of cactus. Hares, skunks, and small deer abound in this part of the Northwest.
- The Gran Chaco
The western Gran Chaco has growths of thorn forest dominated by algaroba (carob trees) in the drier and often saline zones. Quebracho trees (a source of tannin) are present, but not to the extent that they are farther east. No plants survive in areas with finer salt at the surface. Coarse bunchgrasses are common in the dry steppe, which also supports dense scrub forests intermixed with prickly pear, barrel, and many other types of cactus.
The vegetation of the Chaco becomes increasingly lush toward the east. The thorn forests are gradually replaced by dense quebracho forests (though of a less-valuable species than those in the west), and there are some pure stands of algaroba. Some 90 miles (150 km) west of the Paraná River, a few massive trees begin to appear. The rich wildlife of the Chaco includes deer, peccaries, monkeys, tapirs, jaguars, pumas, ocelots, armadillos, capybaras, and agoutis. The vast birdlife includes the flightless rheas, which are protected by a refuge in the area. Streams harbour numerous fish species, including piranhas, and snakes and other reptiles abound.
The vegetation of the Chaco becomes increasingly lush toward the east. The thorn forests are gradually replaced by dense quebracho forests (though of a less-valuable species than those in the west), and there are some pure stands of algaroba. Some 90 miles (150 km) west of the Paraná River, a few massive trees begin to appear. The rich wildlife of the Chaco includes deer, peccaries, monkeys, tapirs, jaguars, pumas, ocelots, armadillos, capybaras, and agoutis. The vast birdlife includes the flightless rheas, which are protected by a refuge in the area. Streams harbour numerous fish species, including piranhas, and snakes and other reptiles abound.
- Mesopotamia
Thin stands of tall wax palms occupy the flood zones of Mesopotamia. Groups of trees and grassy areas form a parklike landscape of noted beauty. Common trees are the quebracho, the urunday, and the guayacán, used for tannin and lumber. Gallery forests growing along rivers become denser and taller in Misiones province. Paraná pines appear at higher elevations. Mesopotamia is a habitat for jaguars, monkeys, deer, tapirs, peccaries, many snake varieties, and numerous birds, notably toucans and hummingbirds, as well as stingless bees.
Since the time of European settlement, vast herds of cattle, as well as horses, have virtually taken over the areas of the landscape not planted in crops, and many native animal populations have dwindled. Flightless rheas still inhabit the Pampas, but guanacos are no longer found there. Both animals are fleet-footed, which is probably why the Indians developed the bola, a device consisting of weights on a short rope thrown to trip the animals. Small deer, introduced hares, and viscacha, a burrowing rodent, are common.
- Patagonia and Tierra del Fuego
Patagonia contains zones of deciduous Andean forests and, east of the Andes, of steppe and desert. The largest area—the steppe region—lies in northern Patagonia between the Colorado River and the port city of Comodoro Rivadavia. This zone represents an extension southward of the monte, which gives way gradually to a xerophytic shrub region without trees except along stream banks. In the extreme west on the Andean border, small stands of araucaria survive, and clumps of wiry grasses are also present. Low scrub vegetation and green grass steppe alternate south of Comodoro Rivadavia to the tip of the continent. Wildlife in the region includes now rare guanacos and rheas, as well as eagles and herons, the Patagonian cavy (mará) and other burrowing rodents, mountain cats and pumas, and various poisonous snakes.
The coniferous and broad-leaved forests of the Patagonian Andes spread into Chile. Antarctic beech and needle-leaved trees mixed with araucaria are common. The Patagonian Andes do not support a flourishing animal life: the smallest known deer, the pudu, dwells there, and wild pigs, introduced by Europeans, have multiplied.
The Valdés Peninsula, located on the Atlantic coast of Patagonia, is known for its wildlife. Of particular note are the numerous marine mammals especially whales, elephant seals, and sea lions—that are found in its waters. In 1999 the peninsula was designated a UNESCO World Heritage site.
It seems likely that grasses in Tierra del Fuego first covered glaciated zones, but forests advanced after volcanic ash settled there. Antarctic beech is plentiful in the valleys and grows along with cypress on steep slopes. A local phenomenon near the southern tip of the continent is species of parrots and other birds more commonly associated with the tropics than with Patagonia. Penguins and seals frequent coastal areas, especially in the south.
see also Argentina Abriviations
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