Which is the World’s Largest Drainage Basin?

Largest drainage basin: The world’s largest drainage basin is the Amazon Basin, located in South America. This immense basin covers an area of nearly 7 million square kilometers (2.7 million square miles) and is drained by the Amazon River, the second-longest river on Earth. Stretching across multiple nations, including Brazil, Peru, Colombia, Bolivia, Venezuela, Ecuador, and Guyana, it forms the most expansive and biologically diverse river system in the world.

Amazon Basin

The Amazon Basin forms the core of the Amazon River system, which holds around 20% of the Earth’s freshwater reserves. The region is home to the Amazon Rainforest, also called the “Lungs of the Earth”, as it generates a significant portion of global oxygen and stores immense amounts of carbon dioxide. The basin supports over 30 million people and shelters one-tenth of all known plant and animal species, making it an unparalleled biodiversity hotspot.

Countries Covered by the Amazon Basin

The Amazon drainage basin extends across seven major South American countries, each contributing uniquely to its ecological richness, cultural diversity, and hydrological system.

•Brazil: About 60% of the Amazon Basin lies within Brazil, making it the largest share-holder of this vast ecosystem. The Amazon River flows mainly through Brazil before reaching the Atlantic Ocean. Cities like Manaus and Belém are key gateways to the rainforest, and the country’s government actively manages vast reserves of tropical wilderness.

•Peru: Known as the birthplace of the Amazon River, Peru hosts the river’s origin in the Andes Mountains. The upper reaches of the Amazon, called the Marañón and Ucayali rivers, meet in Peru to form the main channel. The Peruvian Amazon is famous for its ecotourism, indigenous tribes, and exceptional wildlife diversity.

•Colombia: In Colombia, the Amazon Basin covers the country’s southern region. It is characterized by dense rainforests, winding tributaries, and indigenous communities living in harmony with nature. The Putumayo and Caquetá rivers are major Colombian tributaries feeding the Amazon system.

•Bolivia: Bolivia’s share of the Amazon Basin includes the Madeira River, one of the largest tributaries of the Amazon. The Bolivian Amazon is known for its wetlands, floodplains, and endangered species, making it an important ecological corridor between the Andes and lowland forests.

•Venezuela: The southern part of Venezuela falls within the Amazon Basin. The Casiquiare Canal, a natural waterway connecting the Orinoco and Amazon Rivers, lies in this region — one of the few natural river links between two major drainage systems on Earth.

•Ecuador: Ecuador’s eastern lowlands form part of the Amazon Basin, where lush rainforests thrive under heavy rainfall. This region, often called the Ecuadorian Oriente, is rich in wildlife and home to several indigenous tribes like the Huaorani and Shuar.

•Guyana: The basin’s farthest extent reaches into Guyana, where tropical rainforests meet savannas. Although Guyana’s portion is small, it remains ecologically vital for migratory species and regional water flow regulation.

Together, these seven countries form an interconnected network of rivers, forests, and wetlands that support millions of people and countless species, making the Amazon Basin a true symbol of global natural wealth.

Interesting Facts about the Amazon Basin

1.Massive Water Flow: The Amazon River discharges more water than the next seven largest rivers combined, releasing about 209,000 cubic meters per second into the Atlantic Ocean.

2.Rainforest Diversity: The basin houses the largest tropical rainforest on Earth, with over 16,000 tree species and 2.5 million insect species.

3.Wildlife Richness: It is home to rare and iconic species such as the jaguar, macaw, anaconda, sloth, and pink river dolphin.

4.Heavy Rainfall: The region receives 2000–3000 mm of rainfall annually, ensuring lush vegetation throughout the year.

5.Global Climate Impact: The Amazon Basin influences weather patterns across continents and plays a key role in the global water and carbon cycles.

Read more: Which City is Called the City of Seven Hills?