AMAZON RIVER SYSTEM

___: The Amazon River in South America is the second longest river in the world after the Nile. It is about 3,912 miles (6,296 km) long and runs from the Andes Mountains in Peru through Brazil to the Atlantic Ocean. It contains more water than any other river in the world-more than the Mississippi, the Nile, and the Yangtze combined.

In one second, the Amazon pours more than 5 5 million gallons, or 600,000 cubic meters of water, into the Atlantic Ocean, which dilutes the ocean's saltiness for 100 miles from shore. This river forms one of the world's most important river systems.

The Amazon River makes up for 1/5 of the earth's fresh water. The most distant source of the Amazon was established in 1996, as a glacial stream on a snowcapped 5,597 m (18,363 ft) peak called Nevado Mismi in the Peruvian Andes, roughly 160 km (99 mi) west of Lake Titicaca and 700 km (430 mi) southeast of Lima.

The Amazon, which has the largest drainage basin in the world, about 7,050,000 square kilometers (2,720,000 sq mi), accounts for approximately one-fifth of the world's total river flow. The width of the Amazon varies between 1.6 and 10 kilometers (1.0 and 6.2 mi) at low stage, but expands during the wet season to 48 kilometers (30 mi) or more.

The river enters the Atlantic Ocean in a broad estuary about 240 kilometers (150 mi) wide. The mouth of the main stem is 80 kilometers (50 mi). The Amazon River and its tributaries are characterized by extensive forested areas that become flooded every rainy season. Every year the river rises more than nine meters (30 ft), flooding the surrounding forests, known as "flooded forests".

The Amazon's flooded forests are the most extensive example of this habitat type in the world. In...