RIO DE LA PLATA: HISTORY, CHARACTERISTICS, ROUTE, FLORA, FAUNA - GEOGRAPHY - 2025

The Río de la Plata is located in southern South America, serving as the border between Uruguay and Argentina. It is part of the La Plata Basin, the second largest in the continent with 3,170,000 km ². It occupies part of the territory of Argentina, Bolivia, Brazil, Paraguay and Uruguay, being surpassed only by that of the Amazon.

This South American giant forms an estuary that opens in the shape of a wedge, going from 40 km at its source to approximately 240 km in its widest part. This magnitude makes it worthy of the title of the widest river in the world.

The La Plata River has two main tributaries, the Paraná and Paraguay rivers. Photo: Mel 23

The basin of the La Plata River is estimated at 30,000 km ² over which it travels 300 km from its source to its mouth, discharging an average of 20,000 m ³ / sec into the Atlantic Ocean.

It moves from northwest to northeast within the continent progressively widening its channel due to the action of the tides and the wind that accelerates the erosion of the banks.

History

Sweet sea

The Río de La Plata, like other rivers on the continent, was discovered by Spanish colonizers who embarked on the mission of finding a channel that would connect the Atlantic Ocean with the Pacific Ocean.

It came to the knowledge of the colonizers and was registered on their maps with its own name in 1516 thanks to Juan Díaz de Solís, who gave it the name of Mar Dulce.

Silver river

Subsequently, Alejo García, seduced by the stories of wealth told by the indigenous people of the area, embarked on an expedition that would not come to an end in search of the mythical Sierra de la Plata.

After his death, a group of his companions arrived in Brazil with some pieces of silver that they had obtained from the indigenous people of the area. That, added to the story of their adventures, caused them to rename the river with its current name: Río de la Plata.

Seeking to consolidate its presence and dominance in the new territory, in 1536 the Spanish Pedro de Mendoza founded Santa María de los Buenos Aires on the southern bank of the Río de la Plata, in the place that the city of Buenos Aires currently occupies. This city was abandoned and re-founded in 1580 under another name by Juan de Garay, another Spanish explorer.

Viceroyalty of the Río de la Plata

Around 1776 Carlos III decreed the foundation of the Viceroyalty of the Río de la Plata, covering the territories that currently belong to Argentina, Bolivia, Uruguay and Paraguay, as well as parts of Brazil and Chile.

The capital of this new territorial unit was located in La Santísima Trinidad and Puerto de Santa María del Buen Ayre, the name given to the old Santa María de los Buenos Aires.

British invasions

The stability of the Viceroyalty of the Río de la Plata was disturbed by British invasions that entered the territory going up its waters between 1806 and 1807, trying to occupy the territories of present-day Buenos Aires and Montevideo on both banks of the river.

These efforts were unsuccessful and the invaders were expelled thanks to the defense carried out by the River Plate population without the help of the Spanish kingdom, an event that marked an important milestone in the independence of the territories that made up the Viceroyalty of La Plata.

World War II and later

In World War II, the La Plata River was the scene of the only war episode in the American continent. In December 1939 British ships fought a naval battle against a German ship in the Rio de La Plata.

Seeing himself defeated by those of Great Britain, the German Captain Hans Langsdorff sank his ship to prevent his technology from being taken over by the enemy.

In 1973, in the midst of the economic development of the region, the Rio de la Plata treaty was signed between the governments of Argentina and Uruguay to define the use and exploitation of its water resources.

General characteristics

The geographical location, the composition of the soil, the contribution of its tributaries and its relationship with human activity is what gives the estuary of the Río de la Plata its unique character.

Tributaries

The Río de la Plata has two main tributaries that feed it with 97% of its total channel: the Paraná and Paraguay rivers. The remaining 3% is obtained from the contribution of the San Juan, Salado, Santa Lucía and Luján rivers.

Color

One of the characteristics that most attract the attention of the Río de la Plata is its "tawny" color. This designation refers to a cloudy beige shade that goes from light to dark along the river.

The betas are formed by the effect of the movement of the current of the waters downstream, on its journey to the Atlantic Ocean, combined with the effect of the tides and the oceanic wind that push the waters in the opposite direction. This movement prevents sediments from settling in the river bed, keeping it in perpetual suspension.

One river, two waters

The estuary of the Río de la Plata is saline wedge, this refers to the properties of circulation and distribution of salinity in the mixture. In the case of saline wedge estuaries, the denser salt water flows under the fresh water, mixing only partially below the surface. Thus, salinity on the surface is zero or almost zero and at the bottom it is almost equal to oceanic salinity.

The estuary of the Río de la Plata is saline wedge because the volume of water that moves to the ocean is much higher than the volume of salt water that enters due to the effect of the tides.

It presents a natural barrier called the Barra del Indio, located between Montevideo and Punta Piedras, which divides the river into two parts: the inner zone of fresh water and the outer zone of brackish water.

Coast height

Despite being separated only by the river estuary, the Uruguayan coasts are at a higher altitude than the Argentine ones and are made up of rocks and dunes, which makes them more suitable for the installation of berths without the need for major maintenance work..

On the other hand, the Argentine coasts are made up of sand and clay that arrives in suspension in the river waters. Being lower, they are prone to flooding due to the effect of the tides and require constant maintenance by dredging the material that is deposited in the channels.

Floods

The Río de la Plata presents two periods with well differentiated characteristics: a flood period that coincides with the summer, which is located between October and March, and the low water period that goes from April to September.

In summer 80% of the annual rain falls. These events, together with the tides, winds, climate change and the mismanagement of the underground water of the streams can cause floods that exceed the usual levels, such as those that affect the Autonomous City of Buenos Aires (CABA) with increasing frequency..

tourism

In addition to observing the native fauna and flora, water activities are a great attraction for tourists visiting the Río de la Plata on its Uruguayan and Argentine coasts.

On both coasts there are various alternatives to cross the river water in boats of different depths, sailboat rides, cruises and yachts are common.

Water sports such as surfing, windsurfing and kitesurfing are also widespread thanks to the waves produced by the ocean wind.

Location

The Río de la Plata is located at longitude coordinates O65 ° 16'59.99 ″ latitude S28 ° 36'0 ″ in southeastern South America. Its geographical position makes it an international river, since its waters mark the boundary between two nations: Argentina and Uruguay.

The exercise of sovereignty of both nations was demarcated according to the Rio de la Plata Treaty and its Maritime Front, signed by both parties on November 19, 1973.

Birth

The Río de la Plata is born from the confluence of the Paraná and Uruguay rivers, between Punta Gorda to the north of the Uruguayan department of Colonia, and the Ibicuy Islands to the south of the Argentine province of Entre Ríos.

Some specialists consider it a marginal arm of the Atlantic Ocean or a gulf of it, while others (who represent the majority) affirm that it is a river.

Travel

It travels approximately 300 km from its source at the confluence of its main tributaries (Paraná River and Uruguay River) to its mouth in the Atlantic Ocean, bathing with its waters various locations on both banks.

At its source it touches the coasts of the Uruguayan department of Colonia to the north and the Argentine province of Entre Ríos to the south. The most important towns in this area are located on the Uruguayan coasts, including Punta Gorda, Colonia Estrella, the Zagarzazu Spa and the port of Colonia, all located in the department of Colonia.

On the Argentine coast is the Greater Buenos Aires Metropolitan Area in the province of Buenos Aires. Following the course to the ocean is Montevideo, capital of the Eastern Republic of Uruguay, and Punta Este on the same shore.

In its initial section, the river has islands formed by the detachment of the Paraná delta. Its main attraction is tourism and its areas are very sparsely populated. Among them are Oyarvide, Solís, Juncal, Martín García and Timoteo Domínguez. These islands are constantly growing due to the accumulation of sediments that come from the Paraná River and Uruguay.

Flora

The mixture of fresh and salt water in the Rio de la Plata inlet generates an enormous plant diversity of both aquatic and terrestrial species. These species can be observed along the entire river, especially in areas with lower population density and in protected areas.

Throughout its channel you can see camalotes, water hyacinth, water ferns, Amazon water lily, water cabbage, trumpet, canutillos, cataizales, guama, reed beds, muriti palms, totorales, lapachos, grasslands of Cortaderas, logging, carandá palms, bull, Margarita de bañado, belesa and croton. Likewise, grazing grasslands abound in the area.

Fauna

The enormous amount of solids transported by the suspended waters of the Río de la Plata is a primary factor that limits the river's biodiversity. This is due to the low rate of reproduction of phytoplankton, the organism from which most aquatic species feed.

However, in terrestrial ecosystems a large number of species reproduce that make life on their banks.

Among the most common in the area are the South American otter, tapir, South American sea lion, nutria, plovers, green turtle, catfish, surubíes, goldfish, water boas, loggerhead turtle, green kingfisher, silver dolphin, yararás, freshwater crabs, crab hawks, piranhas, various species of toads and iguanas.

Contamination

By 2010, the Río de la Plata received urban water from 2.89 million inhabitants only from the Autonomous City of Buenos Aires. The population growth of Uruguay and Argentina has continued to rise to date and all the pressure of its inhabitants falls on the river.

The sewers and rainwater carry organic and inorganic waste into their waters that affect their quality, reducing their oxygenation. Likewise, agricultural operations are carried out on its banks that carry chemicals to the river waters with the use of fertilizers.

Economy

The La Plata basin is an essential axis for the economic development and integration of the region. The rivers that compose it together make up the main river communication route through which goods, people and raw materials are regularly transported for regional and global exchange through the Río de la Plata, at its mouth with the Atlantic Ocean.

The main economic activity that takes place in the riverbed of the Río de la Plata is the port. Finished products and raw materials from parts of Brazil, Paraguay, Bolivia, Argentina and Uruguay are transferred through the ports of this river, estimating that they add up to 70% of the GDP of these countries.

The ports of the Río de la Plata are an important pillar with their collection, distribution and export activities for the economic development of the region. Industries of a different nature are also located around the river that take advantage of the easy access to ports for the development of their activities.

References

1. El gran estuario del plata, NGO Argentina Ambiental, taken from argentinambiental.com.
2. Río de la Plata, CCT CONICET Mendoza, taken from mendoza.conicet.gov.ar.
3. Compilation and analysis of issues related to transport infrastructure and cargo movement between the countries of the La Plata Basin, at the request of Resolution No. 124 of the X Meeting of Foreign Ministers of the La Plata Basin Countries in 1978, taken from oas.org.
4. Population and economy section, Framework Program for the Sustainable Management of Water Resources of the La Plata Basin, in Relation to the Effects of Variability and Climate Change, taken from Proyectoscic.org.
5. Oscar Valero, The economy in the Río de la Plata, X Conference on Sociology. Faculty of Social Sciences, University of Buenos Aires, Buenos Aires, 2013. Taken from