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Amazon Rainforest - World Wonders |
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 The Amazon Rainforest is a moist broadleaf forest in the Amazon Basin of South America. The area, also known as Amazonia or the Amazon Basin encompasses seven million square kilometers (1.2 billion acres), though the forest itself occupies some 5.5 million square kilometers, located within nine nations: Brazil (with 60 percent of the rainforest), Colombia, Peru, Venezuela, Ecuador, Bolivia, Guyana, Suriname, and French Guiana. States or departments in four nations bear the name Amazonas after it. The Amazon represents over half of the planet's remaining rainforests and comprises the largest and most species-rich tract of tropical rainforest in the world.
Etymology
The name Amazon is said to arise from a battle which Francisco de Orellana had with a tribe of Tapuyas where the women of the tribe fought alongside the men, as was the custom among the entire tribe. Another theory credits the name to Orellana mistaking indigenous men wearing "grass skirts" as women. Orellana derived the name Amazonas from the ancient Amazons of Asia and Africa described by Herodotus and Diodorus in Greek legends.
Biodiversity
Wet tropical forests are the most species-rich biome, and tropical forests in the Americas are consistently more species rich than the wet forests in Africa and Asia. As the largest tract of tropical rainforest in the Americas, the Amazonian rainforests have unparalleled biodiversity. More than 1/3 of all species in the world live in the Amazon Rainforest.
The region is home to about 2.5 million insect species, tens of thousands of plants, and some 2000 birds and mammals. To date, at least 40,000 plant species, 3,000 fish, 1,294 birds, 427 mammals, 427 amphibians, and 378 reptiles have been scientifically classified in the region. Scientists have described between 96,660 and 128,843 invertebrate species in Brazil alone.
The diversity of plant species is the highest on earth with some experts estimating that one square
kilometer may contain over 75,000 types of trees and 150,000 species of higher plants. One square
kilometer of Amazon rainforest can contain about 90,790 tons of living plants. This constitutes the largest collection of living plants and animal species in the world. One in five of all the birds in the world live in the rainforests of the Amazon. To date, an estimated 438,000 species of plants of economic and social interest have been registered in the region with many more remaining to be discovered or catalogued.
Deforestation
Deforestation is the conversion of forested areas to non-forested areas. The main sources of deforestation in the Amazon are human settlement and development of the land. Between 1991 and 2000, the total area of forest lost in the Amazon rose from 415,000 to 587,000 km², an area twice the size of Portugal, with most of the lost forest becoming pasture for cattle.
History of Deforestation in the Amazon
Prior to the early 1960’s, access to the Amazon was incredibly restricted and aside from partial clearing along rivers the forest remained basically intact. The key point in deforestation of the Amazon was when the colonists established farms within the forest during the 1600s. Their farming system was based on crop cultivation and the slash and burn method. The colonists were unable to successfully manage their fields and the crops due to the loss of soil fertility and weed invasion. The soils in the Amazon are productive for just a short period of time, and the farmers are therefore constantly moving and clearing more and more land. Amazonian colonization was ruled by cattle raising because ranching required little labor, generated decent profits, and awarded social status in the community. However the results of the farming lead to extensive deforestation and caused extensive environmental damage. An estimated 30% of the deforestation is due to small farmers and the intensity within the area that they inhabit is greater than the area occupied by the medium and large ranchers who possess 89% of the Legal Amazon’s private land. This emphasizes the importance of using previously cleared land for agricultural use, rather the typical easiest political path of distributing still-forested areas. In the Brazilian Amazon, the amount of small farmers versus large landholders changes frequently with economic and demographic pressures.
Causes of Deforestation in the Amazon
The annual rate of deforestation in the Amazon region has continued to increase from 1990 to 2003 because of factors at local, national, and international levels. 70% of formerly forested land in the Amazon, and 91% of land deforested since 1970, is used for livestock pasture. In addition, Brazil is currently the second-largest global producer of soybeans after the United States, mostly for livestock feed, and as prices for soybeans rise, the soy farmers are pushing northwards into forested areas of the Amazon. As stated in Brazilian legislation, clearing land for crops or fields is considered an ‘effective use’ of land and is the beginning towards land ownership. Cleared property is also valued 5–10 times more than forested land and for that reason valuable to the owner whose ultimate objective is resale. As stated by Michael Williams, “The people of Brazil have always thought of the Amazon as a communal possession which they felt free to hack, burn, and abandon at will.” The soy industry is the principal source of foreign currency for Brazil; therefore, the needs of soy farmers have been used to validate many of the controversial transportation projects that are currently developing in the Amazon. The first two highways: the Belém-Brasília (1958) and the Cuiaba-Porto Velho (1968) were the only federal highways in the Legal Amazon to be paved and passable year-round before the late 1990’s. These two highways are said to be “at the heart of the ‘arc of deforestation’,” which at present is the focal point area of deforestation in the Brazilian Amazon. The Belém-Brasilia highway attracted nearly two million settlers in the first twenty years. The success of the Belém-Brasilia highway in opening up the forest was re-enacted as paved roads continued to be developed unleashing the irrepressible spread of settlement. The completions of the roads were followed by a wave of resettlement and the settlers had a significant effect on the forest.
Scientists using NASA satellite data have found that clearing for mechanized cropland has recently become a significant force in Brazilian Amazon deforestation. This change in land use may alter the region's climate and the land's ability to absorb carbon dioxide. Researchers found that in 2003, the peak year of deforestation, more than 20 percent of the Mato Grosso state’s forests were converted to cropland. This finding suggests that the recent cropland expansion in the region is contributing to further deforestation. In 2005, soybean prices fell by more than 25 percent and some areas of Mato Grosso showed a decrease in large deforestation events, although the central agricultural zone continued to clear forests. But, deforestation rates could return to the high levels seen in 2003 as soybean and other crop prices begin to rebound in international markets. Brazil has become a leading worldwide producer of grains including soybean, accounting for more than one-third of the country's gross national product. This new driver of forest loss suggests that the rise and fall of prices for other crops, beef and timber may also have a significant impact on future land use in the region, according to the study.
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