"Amazonian" redirects here. For other uses, see Amazonian (disambiguation).
Amazon River basin (the southern Guianas, not marked on this map, are part of the basin)
The mouth of the Amazon River, the second longest river in the world.
The Amazon Basin is the part of South America drained by the Amazon River and its tributaries that drains an area of about 6,915,000 square kilometres (2,670,000 sq mi), or roughly 40 percent of South America. The basin is located in the countries of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, and Venezuela. The Amazon rainforest is the largest in the world, covering about 8,235,430 km2 (3,179,720 sq mi) with dense tropical forest.
1 Plant life
2 Animal life
3 Climate and seasons
4 Human occupation
5 River commerce
6 Sustainable opportunistic agriculture in undeveloped areas
7 Non-sustainable agriculture in developed areas
10 See also
12 Further reading
13 External links
Main article: Amazon Rainforest
Aerial view of the Amazon rainforest, taken from a plane
As much of the Amazon is unexplored, many of its indigenous plants and animals are unknown. Plant growth is dense and the variety of animals living is comparatively more because of the heavy rainfall and the dense forests covered with huge evergreen and coniferous forests. The forests are in fact so thick that the dense "roof" created by the leaves and branches does not allow the sunlight to reach the ground. The ground remains dark and damp. Only shade tolerant trees and vegetation may grow here. Orchids and bromeliads use trees and other plants to get closer to the sunlight. They grow hanging onto the branches or tree trunks with aerial roots, not as parasites but as epiphytes. One tropical fruit tree that is native to the Amazon is the abiu. There are thousands of plants, all in different colors, sizes, and shapes. There are also many other living organisms that have their homes in these plants.
Mammals. More than 10000 species of mammal are found in the Amazon, the majority of which are bats and rodents.
Birds. About 1500 bird species inhabit the Amazon Basin. Macaws are famous for gathering by the hundreds, even thousands, along the clay cliffs of the Amazon river where they feed on minerals which help the birds process toxins found in the seeds they eat.
Reptiles. Many reptiles species are illegally collected and exported for the international pet trade. Live animals are the fourth largest commodity in the smuggling industry after drugs, diamonds, and weapons.
Amphibians . More than 1000 species of frogs are found in the Amazon. Unlike temperate frogs which are mostly limited to habitats near water, tropical frogs are most abundant in the trees and relatively few are found near bodies of water on the forest floor. The reason for this occurrence is quite simple: frogs must always keep their skin moist since almost half of their respiration in carried out through their skin. The high humidity of the rainforest and frequent rainstorms gives tropical frogs infinitely more freedom to move into the trees and escape the many predators of rainforest waters. The differences between temperate and tropical frogs extend beyond their habitat. Whereas nearly all temperate frogs lay their eggs in water, the majority of rainforest species place eggs in vegetation or lay them in the ground. By leaving the water, frogs avoid egg-predators like fish, shrimp, aquatic insects, and insect larvae. Among the best known of rainforest amphibians are the tiny, but brilliantly colored poison dart (arrow) frogs [members of the Dendrobatidae family]. These striking but slow-moving frogs secrete powerful toxins from glands on their backs and use their color to advertise their toxic composition to potential predators
Red-bellied piranha (Pygocentrus nattereri) are a species of piranha. This species lives in the Amazon River Basin, coastal rivers of northeastern Brazil, and the basins of the Paraguay, Parana and Essequibo Rivers.
Fish. With more than 2,200 species the Amazon Basin has a larger fish fauna than any other river basin on Earth, and Amazonia is the center of diversity for Neotropical fishes (Albert and Reis, 2011)
Some of the major fish groups of the Amazon Basin include:-
Order Gymnotiformes: Neotropical electric fishes
Family Characidae: tetras and allies
Family Loricariidae: armoured catfishes
Subfamily Cichlinae: Neotropical cichlids
Subfamily Poeciliinae: guppies and relatives
Insects . Over 90% of the animal species in the Amazon are insects. Whereas all of Europe has some 321 butterfly species, the Manu National Park in Peru (4000 hectare-survey) has 1300 species, while Tambopata National Park (5500 hectare-survey) has at least 1231 species . Around 25% of the world's 2 million described animals species are beetles (Coleoptera). The Longhorn Beetle (Titanus giganteus) can have a body length (not including antennae) of over 6.5 inches (16 cm). A single square mile of rainforest often houses more than 50,000 insect species. Some scientists estimate that 30% of the animal biomass of the Amazon Basin is made up of ants.
Climate and seasons
The Amazon River Basin has low-water season, and a wet season during which the rivers flood adjacent low lying forests. The climate of the basin is generally hot and humid. In some areas, however, the winter months (June?September) can bring cold snaps, fueled by Antarctic winds travelling along the adjacent Andes mountain range. Such cold conditions can be devastating for some of the region's tropical plant and animal species.
Amazonas floating village, Iquitos, Peru
Amazonia is very sparsely populated. There are scattered settlements inland, but most of the population lives in a few larger cities on the banks of the Amazon and other major rivers, such as in Iquitos (Peru), Manaus and Belem (Brazil). In many regions, the forest has been cleared for soy bean plantations and ranching (the most extensive non-forest use of the land) and some of the inhabitants harvest wild rubber latex and Brazil nuts. This is a form of extractive farms, where the trees are not cut down, and thus this is a relatively sustainable human impact.
The largest organization fighting for the indigenous peoples in this area is COICA, which is a supraorganization emcompassing all indigenous rights organizations working in the Amazon Basin area, living in several countries.
The river is the principal path of transportation for people and produce in the regions, with transport ranging from balsa rafts and dugout canoes to hand built wooden rivercraft and modern steel hulled craft.
Sustainable opportunistic agriculture in undeveloped areas
Seasonal floods excavate and redistribute nutrient-rich silt onto beaches and islands, enabling dry-season riverside agriculture of rice, beans, and corn on the river's shoreline without the addition of fertilizer, with additional slash and burn agriculture on higher floodplains. Fishing provides additional food year round, and free-range chickens need little or no food beyond what they can forage locally. Charcoal made largely from forest and shoreline deadfall is produced for use in urban areas. Exploitation of bush meat, particularly deer and turtles is common.
Non-sustainable agriculture in developed areas
Deforestation and increased road-building in the Amazon Rainforest are a significant concern because of increased human encroachment upon wild areas, increased resource extraction and further threats to biodiversity.
Extensive deforestation, particularly in Brazil, is of considerable worldwide concern as it is leading to the extinction of known and unknown species, reducing biological diversity and negatively impacting soil, water, and air quality. A final part of the deforestation process is the large-scale production of charcoal for industrial processes such as steel manufacturing. Soils within the region are generally shallow and cannot be used for more than a few seasons without the addition of imported fertilizers.
The Amazon Basin is bounded by the Guiana Highlands to the north and the Brazilian Highlands to the south. The Amazon, which rises in the Andes Mountains at the west of the basin, is the second longest river in the world. It covers a distance of about 6,400 km before draining into the Atlantic Ocean. The Amazon and its tributaries form the largest volume of water. The Amazon accounts for about 20% of the total water carried to the oceans by rivers. Some of the Amazon Rainforest is deforested because of a growing interest in hardwood products.
The highest point in the watershed of the Amazon is the peak of Yerupaja at 6,635 m (21,768 ft).
Politically the basin is divided into the Brazilian Amazonia Legal, the Peruvian Amazon, the Amazon Region of Colombia and parts of Bolivia, Ecuador and the Venezuelan state of Amazonas.
The most widely spoken language in the Amazon is Portuguese, followed closely by Spanish. On the Brazil side Portuguese is spoken by at least 98% of the population, whilst in the Spanish-speaking countries a large number of speakers of indigenous languages are present, though Spanish is predominant.
There are hundreds of native languages still spoken in the Amazon, most of which are spoken by only a handful of people, and thus are critically endangered. One of the most widely spoken languages in the Amazon is Nheengatu, which is descended from the ancient Tupi language, originally spoken in the coastal and central regions of Brazil. It was brought to its present location along the Rio Negro by Brazilian colonizers who, until the mid-17th century, who primarily used Tupi rather than the official Portuguese to communicate. Besides modern Nheengatu, other languages of the Tupi family are spoken there, along with other language families like Je (with its important sub-branch Jayapura spoken in the Xingu River region and othes), Arawak, Karib, Arawa, Yanomamo, Matses and others.
Earth sciences portal
Amazon Conservation Association
Deforestation by region
Deforestation of the Amazon Rainforest