The Argentine territory is made up of regions that have undergone slow submersion movements and sedimentation processes (Chaco, Pampa, Mesopotamia Argentina) or emergence movements and erosion processes (Patagonia). There are also orogenic zones formed in Precambric periods (Puna area), in the ancient Paleozoic (Sierre pampeane), in the Permian (Precordigliere), in the Cretaceous (some reliefs of Patagonia) and finally in the Tertiary (Andean system).
The Chaco belongs to the Argentina only in the southern part, to the South of Pilcomayo (500,000 km 2); it is about 300 meters high at the foot of the Andes and about eighty meters above Paraguay ; the rivers that cross it have flowed slowly and wandering among numerous marshes. The soil is poor in surface water and the irregularity of the rains makes it unsuitable for agriculture.
La Pampa is a vast region that extends S of Chaco, between the Atlantic and the Andes, to the Río Colorado. The eastern part consists of a low-sloping lowland, with numerous basins, often occupied by lakes and ponds; due to the scarce rains, a steppe of grasses predominates, which man has replaced cereal crops; towards the S rise hills and low mountains (1280 m). The western Pampas (or region of the mountain) is characterized by remarkable reliefs that alternate with the plain and an accentuated aridity of the climate; both spontaneous vegetation and cultivated areas are scarce, and the region is therefore depopulated.
Mesopotamia Argentina (the plain between the Paraná and Uruguay rivers) is partly undulating, partly (N) flat, low and swampy, rich in ponds. The federated province of Misiones, between Brazil and Paraguay, has a hilly surface, carved by valleys and covered by subtropical forests.
AS of Colorado, between the Andes and the ocean, extend the mesetasof eastern Patagonia (800,000 km 2), a depopulated, tabular steppe region, which descends in shelves from the slopes of the Andes to the coast, engraved by large transverse valleys.
AS of the Strait of Magellan is located Tierra del Fuego, which belongs to the Argentina in the eastern part (21,000 km 2); to the North it has physical characteristics similar to Patagonia, while to the South it is crossed by high mountains and has very indented coasts.
The extreme north-eastern part of the country is made up of a very high region (Puna) (3400-4000 m), arid, with wide valleys and closed basins, occupied by salares(depressions covered by saline crusts), with little vegetation. It is limited to the East by a succession of crests reaching 5500m and to the West by a series of volcanoes, some of which exceed 6000m. AS della Puna rise the Sierre Pampeane, three systems arranged from N to S, with gentle and monotonous shapes.
The Cordilleras separate the Argentina from Chile ; the northern part of them (Cordillera Real) goes from the Puna region to the sources of the Neuquén; very high (Aconcagua, 6960 m; Cerro Mercedario, 6770m), has rare and difficult passes and numerous volcanic cones. Remarkable peaks are also found to the South of Aconcagua (Tupungato, 6550 m); only the southern part of the Cordillera has alpine characteristics, since in the northern part, due to the aridity of the climate, the persistent snow limit is very high (6550 m at the lat. of 28 ° S). AE of the Cordillera Real rise the Precordigliere, also over 5000 meters. The Patagonian Andes begin to the South of the sources of the Neuquén and are formed by two series of reliefs, of which the eastern one (the only one involving the Argentina) is divided by numerous transversal valleys; the height here is lower (Monte Tronador, 3554 m; Monte Fitz Roy, 3375 m) and decreases towards the S; the low temperatures due to the high latitude and the high humidity make the Patagonian Andes particularly rich in snow and glaciers.
The extension of the Argentine territory in the sense of the meridians involves very different climatic types. The Chaco has a subtropical climate, with warm summers and mild, dry, sunny winters and with scarce rainfall the further one proceeds towards the West (from 900 to 500 mm per year) and distributed in a few months. The Pampas have a steppe climate, with high temperatures and mild winters, but little rain. Mesopotamia Argentina, with a short zone to the West of Paraná, has a subtropical climate without a dry season, with strong thermal variations and abundant rainfall. Patagonia is desert, with harsh winters and very scarce rains (200-400 mm per year). The climate of the mountainous regions (Puna and Cordillera) varies with altitude and latitude: to the North the rains are very scarce (less than 200 mm per year), to the South they increase due to the humid westerly winds. Winds characteristic of the Argentina I’m thepampero, which blows from SW, cool, dry and violent; the norte, hot wind coming from the N; the southeastern, cold and humid, capable of repelling the waters of the Río de la Plata towards the land, thus causing very high tides and floods in the estuary.
Regarding hydrography, half of the Argentina pours its waters into the Atlantic, for the most part, and into the Pacific; the other half has no flow to the sea. The most important of the Atlantic rivers is the Paraná (3900 km). Grandiose waterfalls interrupt its course and that of its tributaries (the main one is Paraguay, 2230 km), in turn swelled by other notable rivers, such as the Pilcomayo (1800 km) and the Bermejo (1150 km). The Paraná-Paraguay system can be traced by large ships up to 600 km upstream from Buenos Aires. Uruguay (1650 km) is also rich in water and well navigable; it flows into the Paraná forming the great estuary called Río de la Plata. The other rivers on the Atlantic side are Patagonian and originate from the Cordillera (Río Colorado, 1300 km; Río Negro, 1250; Chubut, 750; Deseado, 600). In arid areas of land or very permeable network hydrographic is poorly developed and rivers are lost in salinas, in lagunas, in Bañados etc. Lake basins in large numbers are found both in the Pampas region, both in the Mesetas of Patagonia (Colhue Huapi, 750 km 2), and in the Andes of Patagonia (Lake Nahuel Huapi, 560 km 2).; Lake Buenos Aires, 2020; San Martín Lake, 1200; Viedma Lake, 1500; Argentino Lake, 1420). Almost all of the W side of the Patagonian Andes is tributary of the Pacific, with rivers rich in water and of great erosive capacity, which have often given rise to capture phenomena to the detriment of the upper reaches of the Atlantic rivers. For Argentina geography, please check franciscogardening.com.
The biogeography of the country has in the territory of the province of Misiones, in the N Mesopotamia Argentina and on the eastern slopes of the mountainous region a prevalence of tropical forest, formed mostly by Araucaria brasiliensis,from Ilex paraguayensisand two species of Podocarpus,while the Andes of Patagonia (to the South of the parallel of 38 °) are covered with temperate forests, formed especially by southern beech, lauraceous and conifers. In Chaco the forests alternate with xerophilous scrubs and savannas, where grasses prevail. Mesopotamia Argentina is largely covered by woods of acacias and mimosas, alternating with grasslands; along the rivers, the woods have a more hygrophilic character. In the Puna the vegetation, which rises up to almost 5000 m, is scarce and consists only of shrubs and grasses. In the western part of the Pampa, formations of acacias and shrub plants prevail, while in the eastern part the grass steppe predominates. The Patagonian shelves up to the foot of the Cordillera are covered by a mixed formation of low thorny shrubs and grasses.
From the zoogeographical point of view, the northeastern part of the country is an area in itself, with fauna similar to that of Brazil: monkeys, tapirs, jaguars, toucans, boas and caimans. In the rest of the territory there are three areas: that of the Pampas, to the S of the previous one up to the Río Negro, of which the viscacha, the rhea (or American ostrich) and the collared kaimiki are characteristic; the arid zone, which includes Patagonia and Tierra del Fuego, with the guanaco and Magellan’s goose; the Andean area, with the vicuña, the chinchilla and the condor. The Argentine fauna, as a whole, is especially rich in Rodents and Toothless. There are also various Didelphid Marsupials. The large Carnivores are represented by the jaguar and the puma. Among the ruminants, the lamas are typical, as in Peru and Bolivia, they are only domestic. The avifauna is very rich: it includes all the characteristic types of American birds, as well as two particular species of Reiformi: the rhea and the small ostrich. On the coasts of the southern end of the Argentina some species of penguins live, including the king penguin. Relatively scarce are the Reptiles and the Amphibians. The freshwater fish fauna is abundant and interesting. Among the invertebrates, insects are the most widely represented. As in other American countries, colonization introduced Argentina all the domestic animals of Europe, some of which constitute the main source of wealth in the country.
