The geography of Argentina is heavily diverse, consisting of the Andes Mountains, pampas, and various rivers and lakes. Bordered by the Andes in the west and the South Atlantic Ocean to the east, its neighbouring countries are Chile to the west, Bolivia and Paraguay to the north, and Brazil and Uruguay to the northeast.
The Río de la Plata, also called the River Plate or La Plata River in English, is the estuary formed by the confluence of the Uruguay River and the Paraná River at Punta Gorda. It empties into the Atlantic Ocean and forms a funnel-shaped indentation on the southeastern coastline of South America. Depending on the geographer, the Río de la Plata may be considered a river, an estuary, a gulf, or a marginal sea. If considered a river, it is the widest in the world, with a maximum width of 220 kilometres (140 mi).
The Uruguay River is a major river in South America. It flows from north to south and forms parts of the boundaries of Brazil, Argentina and Uruguay, separating some of the Argentine provinces of La Mesopotamia from the other two countries. It passes between the states of Santa Catarina and Rio Grande do Sul in Brazil; forms the eastern border of the provinces of Misiones, Corrientes and Entre Ríos in Argentina; and makes up the western borders of the departments of Artigas, Salto, Paysandú, Río Negro, Soriano and Colonia in Uruguay.
The Paraná River is a river in south-central South America, running through Brazil, Paraguay, and Argentina for some 4,880 kilometres (3,030 mi). Among South American rivers, it is second in length only to the Amazon River. It merges with the Paraguay River and then farther downstream with the Uruguay River to form the Río de la Plata and empties into the Atlantic Ocean.
The Paraguay River is a major river in south-central South America, running through Brazil, Bolivia, Paraguay and Argentina. It flows about 2,695 kilometres (1,675 mi) from its headwaters in the Brazilian state of Mato Grosso to its confluence with the Paraná River north of Corrientes and Resistencia.
The Falkland Current is a cold water current that flows northward along the Atlantic coast of Patagonia as far north as the mouth of the Río de la Plata. This current results from the movement of water from the West Wind Drift as it rounds Cape Horn. It takes its name from the Falkland Islands. This cold current mixes with the tropical Brazil Current in the Argentine Sea, giving it its temperate climate.
The Argentine Naval Prefecture is a service of Argentina's Security Ministry charged with protecting the country's rivers and maritime territory. It therefore fulfills the functions of other countries' coast guards, and furthermore acts as a gendarmerie force policing navigable rivers.
The Río de la Plata basin, more often called the River Plate basin in scholarly writings, sometimes called the Platine basin or Platine region, is the 3,170,000-square-kilometre (1,220,000 sq mi) hydrographical area in South America that drains to the Río de la Plata. It includes areas of southeastern Bolivia, southern and central Brazil, the entire country of Paraguay, most of Uruguay, and northern Argentina. Making up about one fourth of the continent's surface, it is the second largest drainage basin in South America and one of the largest in the world.
The Humid Pampas is an extensive ecoregion of flat, fertile grassland of loessic origin in Argentina. It has a precipitation average of 900 mm per year, in contrast with the Dry Pampas to the west, which average less than 700 mm.
The Uruguayan savanna, also known as the Brazilian-Uruguayan savanna, is a subtropical grassland and savanna ecoregion which includes all of Uruguay and southernmost Brazil, along with portions of Argentina along the Uruguay River. In Brazil, this ecoregion is known as Pampas.
The short-tailed river stingray is a species of river stingray native to the Río de la Plata Basin in South America. It is sometimes known as the giant freshwater stingray, but this name is typically used for Urogymnus polylepis.
In oceanography, a front is a boundary between two distinct water masses. The formation of fronts depends on multiple physical processes and small differences in these lead to a wide range of front types. They can be as narrow as a few hundreds of metres and as wide as several tens of kilometres. While most fronts form and dissipate relatively quickly, some can persist for long periods of time.
The Argentina–Uruguay border is a line of 579 km marked by the Uruguay River, and is the border between Argentina and Uruguay. It starts in a triple border Argentina-Uruguay-Brazil, at the mouth of the Quaraí River in the Uruguay. The course follows the Uruguay river, passing west of the Uruguayan departments of Artigas, Salto, Paysandu, Rio Negro, Soriano and Colonia and the Argentine provinces of Corrientes, Entre Rios and Buenos Aires, until the confluence of the Uruguay and the Paraná rivers into the Rio de la Plata.
Temperate South America is a biogeographic region of the Earth's seas, comprising the temperate and subtropical waters of South America, including both the Pacific and Atlantic coasts of the continent and adjacent islands. It also includes the remote Gough Island and Tristan da Cunha in the South Atlantic Ocean.
The Guianan marine ecoregion stretches along the middle of the northeast coast of South America, touching Venezuela, Guyana, Suriname and French Guiana. It extends about 200 miles offshore, with the warm Guianan Current moving east-to-west through the region. This current brings in fresh, turbid waters from the mouth of the Amazon River to the east. As the current exits the ecoregion to the west it contributes an estimated 70% of the waters of the Caribbean Sea. A very large oil field has been recently discovered in the Guyana-Suriname Basin of the ecoregion. The Guianan is one of two ecoregions in the North Brazil Shelf province, a Large marine ecosystem (LME). The Guianan is thus part of the larger Tropical Atlantic realm.
The Amazonia marine ecoregion covers the coastal marine environment off the mouth of the Amazon River on the continental shelf of Brazil. The warm North Brazil Current moves east-to-west across the river's outlet, carrying turbid, fresh water to the northwest towards the Caribbean Sea. The Amazonia is one of two ecoregions in the North Brazil Shelf province, a large marine ecosystem (LME). It is thus part of the Tropical Atlantic realm.
The Rio Grande marine ecoregion covers the waters offshore of the southern Brazilian states of Rio Grande do Sul and Santa Catarina. The ecoregion stretches along 500 miles of sandy beach coast, and 200 miles out to sea. The warm Brazil Current flows south through the region in parallel with the coast. The continental shelf is smooth and flat, with the bottom mostly sand and mud. Overfishing is a problem, but marine life in recent years has benefited from measures such as a 2018 ban on motorized shrimp trawler fishing within 12 miles of the Rio Grande do Sul coast. The Rio Grande ecoregion is one of four coastal marine ecoregions in the Warm Temperate Southwestern Atlantic marine province. It is thus part of the Temperate South America realm. .
The Uruguay - Buenos Aires Shelf marine ecoregion covers waters offshore of Uruguay, the mouth of the Rio de la Plata), and Buenos Aires Province of Argentina. It has an area of 258,490 square kilometres (99,800 sq mi) and a coastline of 1,300 kilometres (810 mi). Marine biodiversity is very high due to the mixing of currents, the mixing of fresh and salt water, the mixing of temperatures, and the broad, shallow continental shelf. Large amounts of nutrients arrive from the northwest flowing Malvinas Current and from the continental runoff of the Rio de la Plata. Aside from high populations of fish there are colonies of marine mammals, sea turtles, and seabirds.
The North Patagonian Gulfs marine ecoregion covers the gulfs and continental shelf of the middle Patagonian coast of Argentina. As the name suggests, the coast is indented with large gulfs - San Matías Gulf (north), Golfo Nuevo (middle) and San Jorge Gulf (south). The broad, protected areas and rocky reefs support abundant fisheries. The abundance of rocks, promontories and islands support breeding sites for marine mammals and colonies of seabirds. The area is, however, under pressure from over-harvesting of mollusk and crustacean beds, and from development and tourism. The entire ecoregion is on the Patagonian Shelf. The ecoregion is part of the Magellanic marine province. It is thus part of the Temperate South America realm. .
