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The Amazon Rainforest. “…trees of a thousand kinds and tall, so that they seem to touch the sky. I am told they never loose their foliage, and this I can believe for I saw them as green and lovely as they are in Spain in May..” Christopher Columbus.
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The Amazon Rainforest “…trees of a thousand kinds and tall, so that they seem to touch the sky. I am told they never loose their foliage, and this I can believe for I saw them as green and lovely as they are in Spain in May..” Christopher Columbus
IntroductionThe Amazonian Rainforest in South America covers more than 1 billion acres including areas in Brazil, Venezuela, Columbia and East Ecuador and Peru. • Rainforests are being destroyed for the money that can come from the timber, agriculture and cattle grazing. Since the 1970’s the Brazilian government have encouraged the development of the Amazon region. They use some of the money to pay off debts.
Causes of Deforestation Forestry Trees are felled to make furniture. Commercial timber companies cut down hardwood trees such as Teak, Ebony, Mahogany and Rosewood because they have good colour and beautiful grain patterns. When made into furniture these are very valuable. However to reach these valuable trees, the loggers fell many other trees that are of no use.
Ranching Large areas of the forest have been bought by multi-national companies for cattle ranching. These companies have burnt down the forest and replaced the trees with grass. During the 1970’s huge fires raged in different parts of the forest. The beef from the cattle ranches goes mostly to fast food chains to make into burgers. Next time you eat a burger remember it may be the reason why part of the rainforest has been destroyed!
Mining Large mining companies have felled trees and built roads to quarry the huge deposits of mineral ores in the include iron ore, gold, copper and bauxite rainforest. Minerals. This mining helps to bring money into Brazil.
Roads New roads have been built deep into the rainforest. The Trans-Amazonian highway is the longest, and stretches 5300km from east to west Brazil. The roads help move timber, cattle and crops to markets. People from other parts of Brazil, such as the overpopulated coastal areas, have settled along these roads.
HEP The rainforest has huge amounts of rainfall each year and this unlimited water supply and the ideal river conditions have led to the building of many hydro-electric power (HEP) stations. They provide cheap and plentiful energy for industry, transport and domestic use. The reservoirs behind the dams flood large areas of the forest. In the next 15 years more than 125 new HEP dams are to be built.
Farming The indigenous population, known as the Amerindians, have a way of life that shows deep respect for the the forest. They clear areas of the forest for growing crops, but move on when the crops do not grow so well leaving the clearings to be ‘reclaimed’ by the forest. However it takes many years for the clearings to fill with trees and shrubs again. No irreversible damage is done though. However, they clear areas by cutting down the vegetation and setting fire to it. This is known as the ‘Slash and Burn’ method. It provides ash, a natural fertiliser, for the soil. These fires, however, can get out of control if left unattended.
Local EffectsSoil The loss of trees exposes the soil to the full force of the rain. The soil is easily washed away causing soil erosion and nutrients are washed through the soil (leaching) and aren’t held in it. Therefore the soil looses it’s goodness and is no good for growing crops or grass, and the chances of forest regeneration are small.
Flooding Trees catch the rain before it reaches the ground. The roots of trees take up moisture from the soil. They therefore help prevent flooding. With the trees gone there is nothing to intercept the rainfall so it flows straight into the rivers which can then flood. More soil is also carried into rivers blocking them and increasing flooding.
Change in local climate Deforestation leads to reduced rainfall and higher local temperatures. Rain is no longer taken up by trees and released by evapotranspiration, therefore there is no condensation to form clouds and therefore there is less rainfall. This can lead to crop failure.
Loss of the tribal population’s way of life Since the arrival of the 1st European invaders 500 years ago, the indigenous population have seen their land stolen, traditions destroyed and their people murdered. More than 80 indigenous cultures have been wiped out since the beginning of the 20th century. Westerners have brought diseases with them to which the indigenous population are not immune, and many tribes have been wiped out by epidemics. Westerners also brought their cultural influences such as clothes and equipment, leading to a loss of the traditional way of life.
Many tribes have been moved due to the building of dams which flood their land. Mining has cleared large areas and mining waste has poisoned rivers which the indigenous population use for fishing. New roads have cut through forest and damaged tribal land. Many of the indigenous population have been forced off their land by violent cattle ranchers and other companies, some have even been murdered.
Global effectsLoss of habitat Between 5-9 million species of plants, animals and insects live in the tropical rainforests. Experts estimate that we are loosing up to 137 species every day as their rainforest habitat is destroyed. A wide variety of these species can be used as food (fruit and nuts), as medicines and as industrial products (rubber). Scientists think the rainforest contains many undiscovered species and it is possible that these could be used to develop new crops or medicines in the future. Cutting down the forest destroys this chance.
Global warming The rainforest uses carbon dioxide in the process of photosynthesis, so removing the forest means less carbon dioxide is taken out of the atmosphere and therefore global warming increases. Carbon dioxide is also released from the burning of vegetation and therefore burning also contributes to global warming.
These are some of the main causes and effects of deforestation in the rainforest. Will this beautiful habitat be gone for ever in a few decades?