Why are they being destroyed?
In the past 50 years much of the rainforest in Africa and Asia has been destroyed. Large areas of rainforest are being cut down, often in order to remove just a few logs, and rainforest is being destroyed at double the rate of all previous estimates. Unfortunately this means that there is a very high rate of extinction, as the wildlife depending on the forest dies with it.
Many rainforests in Central and South America have been burnt down to make way for cattle farming, which supplies cheap beef to North America, China and Russia. It is estimated that for each pound of beef produced, 200 square feet of rainforest is destroyed. In the past 20 years Costa Rica has lost the majority of its forests to beef cattle ranching. This is known as slash and burn farming and is believed to account for 50% of rainforest destruction. However, the land cannot be used for long: the soil is of poor quality and, without the forest, quickly becomes very dry. The grass often dies after only a few years and the land becomes a crusty desert. The cattle farmers then have to move on and destroy more rainforest to create new cattle pastures.
Indigenous Indians also use “slash and burn” farming techniques, but on a small scale. For centuries they have used a sustainable system where, when they finish using one small patch of land, they move away to a different area and allow the forest to regenerate. Since the area cleared is small, the soil does not dry out and therefore the forest clearance is localized and temporary rather than extensive and permanent.
This is believed to be the second largest cause of deforestation. Timber companies cut down huge trees such as mahogany and teak and sell them to other countries to make furniture. Smaller trees are often used for the production of charcoal. Vast areas of rainforest are cut in one go (clear felling) and the most valuable trees are selected for timber, leaving the others for wood chipping. The roads that are created in order to cut and remove the timber often lead to further damage: see the effect of forest roads under “Oil Companies”.
Much of the fruit, cereals and pulses we buy from tropical countries have been grown in areas where tropical rainforests once thrived. The forests are cut down to make way for vast plantations where products such as bananas, palm oil, pineapple, sugar cane, tea and coffee are grown. As with cattle ranching, the soil will not sustain crops for long, and after a few years the farmers have to cut down more rainforest for new plantations.
The developed nations relentlessly demand minerals and metals such as diamonds, oil, aluminium, copper and gold, which are often found in the ground below rainforests. The rainforests therefore have to be removed in order to extract them. Poisonous chemicals are sometimes used to separate the waste from the minerals, for example mercury, which is used to separate gold from the soil and debris with which it is mixed. These chemicals often find their way into rivers, polluting water supplies which local people depend on, killing fish and other animals that feed on them.
Rainforests are seriously affected by oil companies searching for new oil deposits. This is incredibly damaging as often large roads are built through untouched forests in order to build pipelines and extract the oil. This encourages settlers to move into hitherto pristine forests and start slash-and-burn farming or cutting more timber for sale or the production of charcoal.
Once established, the oil pipelines which transport the oil often rupture, spouting gallons of oil into the surrounding forest, killing wildlife and contaminating the water supplies of local villages.
The World Bank and large companies invest money in developing countries to build dams for the generation of electricity. This can involve flooding vast areas of rainforest. Dams built in rainforest areas often have a short life because the submerged forest gradually rots, making the reservoir water acidic, which eventually corrodes the dam turbines. The dams can also become blocked with soil washed down from deforested highlands in heavy rains. This can cause great problems, such as flooding.
Since 1978 over 750,000 square kilometers (289,000 square miles) of Amazon rainforest have been destroyed across Brazil, Peru, Colombia, Bolivia, Venezuela, Suriname, Guyana, and French Guiana. Why is Earth’s largest rainforest being destroyed?
For most of human history, deforestation in the Amazon was primarily the product of subsistence farmers who cut down trees to produce crops for their families and local consumption. But in the later part of the 20th century, that began to change, with an increasing proportion of deforestation driven by industrial activities and large-scale agriculture. By the 2000s more than three-quarters of forest clearing in the Amazon was for cattle-ranching.
The result of this shift is forests in the Amazon were cleared faster than ever before in the late 1970s through the mid 2000s. Vast areas of rainforest were felled for cattle pasture and soy farms, drowned for dams, dug up for minerals, and bulldozed for towns and colonization projects. At the same time, the proliferation of roads opened previously inaccessible forests to settlement by poor farmers, illegal logging, and land speculators.
But that trend began to reverse in Brazil in 2004. Since then, annual forest loss in the country that contains nearly two-thirds of the Amazon’s forest cover has declined by roughly eighty percent. The drop has been fueled by a number of factors, including increased law enforcement, satellite monitoring, pressure from environmentalists, private and public sector initiatives, new protected areas, and macroeconomic trends. Nonetheless the trend in Brazil is not mirrored in other Amazon countries, some of which have experienced rising deforestation since 2000.