Forestry
Tropical hardwoods such as ebony and mahogany are obtained by logging companies. The timber is a valuable source of foreign income for Brazil, but little attempt is made to replant. There is a large demand for these woods from MEDCs.
Minerals
The rainforest possesses great mineral wealth, including iron ore, bauxite, manganese, diamonds, silver and gold. Mining companies have cut down trees and built roads and railways through the forest to get to these deposits. Carajas contains the largest single iron ore reserve in the world – 18 billion tonnes. Miners will be busy here for more than 300 years. The European Union and the World Bank provided a large share of the financial backing for the project. The short-term gain for the EU was a 15-year guarantee of 13.6 million tonnes a year at a bargain price.
Hydro-electric power
The rainforest has an unlimited supply of water, and good conditions for HEP development. More than 125 HEP dams are built in the next 15 years, but the vast areas of forest will be flooded by the creation of large lakes.
Settlement
Large areas of forest have been cleared for the development of new settlements. In 1960, the population of the Amazonia was 2 million. Now it is more than 30 million.
TASKS
1). Environmentalists think that tropical rainforests are so important because they fear the loss of the rainforests unique biodiversity. They point out the Amazons home to plant species which provide everything from chocolate to today’s most important medicines.
2). Deforestation affects the environment at a local and global scale as once all the trees are cut down, all other elements of the environment are affected. The animals and insects lose their habitats. Without a forest canopy, the soil is exposed to the full force of the heavy rainfall, leading to soil erosion and flooding. In the long term, the absence of the canopy interrupts the daily rhythm of rainfall. Interception decreases and there is less evapotranspiration. This results in a change in climate, with reduced levels of rainfall and ultimately desertification.
The destruction of the forest poses a huge global climate threat. The trees take in carbon dioxide and give out oxygen. Deforestation affects the planets atmospheric balance, accelerating global warming. The burning of trees further pollutes the atmosphere, increasing levels of carbon dioxide.
3a).The research was conducted by interviewing 1393 wood mill operators, representing more than half the mills in 75 Amazonian logging centres.
b). Logging causes greater damage than previously thought as they found out that logging crews annually cause severe damage to between 10 000 and 15 000 sq. km of forest that are not included in current deforestation estimates. They also discovered that fires burning on the surface consume large areas of forest which again are not recorded.
c). Researchers feel that the Brazilian governments monitoring of deforestation using satellite images alone is not accurate enough, as they found that only a tenth of the area classified as forest actually supported undisturbed forest. The researchers say: ‘Satellite-based deforestation monitoring is an essential tool in studies of human effects on tropical forests, because it documents the most extreme form of land use, over large areas, and at low cost.’ But this monitoring needs to be expanded to include forests affected by logging and surface fire if it is to accurately reflect the full magnitude of human influences on tropical forests.
