Amazon Basin
As the Amazon Basin (also Amazon, portug.: Bacia do rio Amazonas) the catchment area of the Amazon, the Rio and the Rio Tocantins Anapu is called. Its river system empties into the Atlantic at Belem. It covers almost the entire northern half of the continent South America. The largest current level of South America, an equatorial rain forest lowlands, they forming water receives first and foremost from the Andes, where her main flow direction has yet to north and then changes across the entire continent to the east. North of the separate through the highlands of Guiana Orinoco level, but this is about the Casiquiare that flow to both streams over the major Amazon tributary Rio Negro, connected, and to the south lies the plain of the Río Paraguay and Paraná. The Amazon Basin has the world's largest water yield (see " Drain ) ".
- 2.1 Flora
- 2.2 Fauna
- 5.1 Important cities
Geography
The Amazon basin is situated amongst the cities of La Paz, Quito, Belem ( South, North, East) circumscribed triangle. It includes areas in the states of Brazil, French Guiana, Suriname, Guyana, Venezuela, Colombia, Ecuador, Peru and Bolivia. It is about 7 million square kilometers, equivalent to about five percent of the total land surface of the earth, the largest contiguous natural area and thus also the second largest contiguous forest of the planet after the boreal forest.
The area referred to a landscape that is dominated by the huge river system of the Amazon, thus also including his 1000 "larger" tributaries. In addition, from the south of the two final section parallel rivers (Rio Anapu and Tocantins ). The largest part of the Amazon basin (approximately two thirds of the area) belongs to Brazil. It is not only the Amazon a mighty river (specifically electricity), but also many of its tributaries. Ten of these are in turn to the twenty-five most water-rich rivers of the world, including even a tributary of a tributary, namely the Rio Branco. During the rainy season, large parts of the Amazon basin are flooded. In the Amazon basin numerous nature reserves have now been reported, including the largest of Peru, which is also the second largest in the Amazon basin, Pacaya Samiria.
River system
It is estimated that the Amazon Basin flows around a fifth of all the world's freshwater. In this case, the tank has a small gradient such that the fluxes usually only have a very low flow rate. For the Amazon, that the slope is approximately five centimeters per kilometer. Depending on the season less than 100,000 or even 200,000 cubic meters of water per second, the Atlantic Ocean to be supplied. The major tributaries of the Amazon can be distinguished by their colors. The Rio Negro is its color black ( black water) already in the name. The Madeira River is considered to be yellow-red river, the Rio Tapajós and the Rio Xingu have clear water (clear water ), which appears blue-green from a distance and from the plane. In general, the dark rivers ( blackwater rivers ) rather from the north ( ie to the left side), the bright (mud or white water) rather from the south (ie right side ) accrue. The reason lies in the soil and thus the erosion of the traversed regions or source areas.
Climate
There is only humid tropical climate time of day, in the Amazon basin, which means it is very hot all year round with humidity often more than 90%. It comes almost daily to rich precipitates. The annual rainfall is about 2000 mm in many places, which corresponds to two to three times the value achieved in Germany. This usually heavy rains also bring additional nutrients along with it. They are contained in the dust that was stirred up and then carried by the wind to Amazonia often in thousands of kilometers (eg the Sahara). There he is taken in by the huge tropical storms and comes with the rain back to earth. The nutrients contained in dust are then incorporated into the nutrient cycle of the rainforest. In many places of the Amazon basin, the average temperatures for each month of the year vary only slightly between 26 ° C and 28 ° C. The maximum daily temperatures are usually between 30 ° C and 40 ° C, while frequent night temperatures between 20 ° C and 30 ° C are reached.
Flora and Fauna
The Amazon rainforests stretched throughout 2007 on an area of about 110 million hectares. Of these, around 22 million hectares were (20 percent) under state protection, around 23 million hectares ( 21 percent) were reported as indigenous settlement area, about 26.5 million hectares (24 percent) - with sometimes dubious evidence of title - privately owned, and 38.5 million hectares (35 percent) were " freely available ", ie without official land use plan.
Flora
The vegetation in the Amazon region is very heterogeneous. A rough subdivision of the most common forms of vegetation includes: Dense forests, open forests with palms, liana forests, dry forests, mountain forests ( especially in the Andean slope ), floodplain forests ( várzea ), swamp forests ( Igapó ), the flooding -free forest types collectively referred to as Terra Firme Forest be. In addition, local formations such as mangrove forests, forest-free savannas ( campos naturais ), Caatinga, etc. Scientists have calculated that there are about 16,000 tree species in the Amazon, with half of all individual trees in the region belong to only 227 species.
Terra preta is a fertile, anthropogenic black earth, which is used in the vicinity of the Amazon and its tributaries.
Fauna
The Amazon region is characterized among other things by its great biodiversity. The actual number of species in the Amazon region is difficult to estimate, since only a fraction has been discovered and described by them. It is assumed that a number of between five and ten million species. Of these, about 1.4 million have been described so far, including 750,000 insects, 40,000 vertebrates, 250,000 plants and 360,000 microbiota. It is estimated that in the region about a quarter of the living animal and plant species have their habitat. The fish fauna is estimated at 2,000 species, more than in all other rivers in the world.
Population
In the Amazon region, about 22 million people. Of these totals approximately one million to one of the various indigenous peoples in the region. In the Brazilian part of the Amazon region 150 different indigenous peoples are distinguished, there live some of the recent so-called uncontacted peoples.
Other significant population groups are traditional bank residents ( Ribeirinhos ) who came to the part during the rubber boom in the region and lived by rubber cones. Later came settlers ( colonos ) loan, which were assigned as part of government resettlement activities for development of the region Land for agriculture. Between the farmers and ranchers on the one hand, which endanger large-scale deforestation, the rubber forests, and the Seringueiro movement on the other hand, which is dependent on these forests for their livelihoods, large stresses incurred in the sequence. More people came in the context of industry and commerce in the region, particularly in Manaus by the establishment of a free trade zone.
Policy
The riparian countries of the Amazon basin in 1978 adopted a Convention for Cooperation in the Amazon region ( Tratado de Cooperación amazonica, TCA). Out of this came in 2003, the organization of the Amazon Cooperation Treaty ( ACTO ), headquartered in Brasília forth.
Ecological problems
In the 70s of the 20th century large highways was begun with the construction of their lines, there was a wide -scale deforestation by agricultural colonists and later be operated by cattle landowners in the following years. In addition, it came through the mining of iron ore, tin, gold, oil and bauxite deposits to the other large -scale deforestation of the tropical rain forest. These clearings on today and have already led to ecological damage with effects on flora and fauna.
Major cities
For the infrastructure of the surrounding areas important towns in the Amazon region are: