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Causes of Forest Destruction
IMMEDIATE CAUSES
The immediate causes of rainforest destruction are clear. The main causes of total clearance are agriculture and in drier areas, fuelwood collection. The main cause of forest degradation is logging. Mining, industrial development and large dams also have a serious impact. Tourism is becoming a larger threat to the forests.
1.1 Logging
Commercial logging companies cut down mature trees that have been selected for their timber. The timber trade defends itself by saying that this method of 'selective' logging ensures that the forest regrows naturally and in time, is once again ready for their 'safe' logging practices (WWF).
In most cases, this is untrue due to the nature of rainforests and of logging practices.
Large areas of rainforest are destroyed in order to remove only a few logs. The heavy machinery used to penetrate the forests and build roads causes extensive damage. Trees are felled and soil is compacted by heavy machinery, decreasing the forest's chance for regeneration.
The felling of one 'selected' tree, tears down with it climbers, vines, epiphytes and lianas. A large hole is left in the canopy and complete regeneration takes hundreds of years.
Removing a felled tree from the forest causes even further destruction, especially when it is carried out carelessly. It is believed that in many South East Asian countries 'between 45-74% of trees remaining after logging have been substantially damaged or destroyed' (WWF).
The tracks made by heavy machinery and the clearings left behind by loggers are sites of extreme soil disturbance which begin to erode in heavy rain. This causes siltation of the forests, rivers and streams. The lives and life support systems of indigenous people are disrupted as is the habitat of hundreds of birds and animals.
Little if any industrial logging of tropical forests is sustainable. The International Tropical Timber Organisation (ITTO), the body established to regulate the international trade in tropical timber, found in 1988 that the amount of sustainable logging was "on a world scale, negligible".
"Logging roads are used by landless farmers to gain access to rainforest areas. For this reason, commercial logging is considered by many to be the biggest single agent of tropical deforestation"
Apart from its direct impact, logging plays a major role in deforestation through the building of roads which are subsequently used by landless farmers to gain access to rainforest areas. These displaced people then clear the forest by slashing and burning to grow enough food to keep them and their families alive, a practice which is called subsistence farming. This problem is so widespread that Robert Repetto of the World Resources Institute ranks commercial logging as the biggest agent of tropical deforestation. This view was supported by the World Wide Fund for Nature's 1996 study, Bad Harvest?, which surveyed logging in the world's tropical forests.
Most of the rainforest timber on the international market is exported to rich countries. There, it is sold for hundreds of times the price that is paid to the indigenous people whose forests have been plundered. The timber is used in the construction of doors, window frames, crates, coffins, furniture, plywood sheets, chopsticks, household utensils and other items.
Solutions: For all purposes for which tropical timber is used, other woods or materials could be substituted.
We can stop using tropical timber and urge others to do the same. As long as there is a market for tropical timbers, trees will continue to be cut down. Labelling schemes, aimed at helping consumers to chose environmental friendly timbers, are currently being discussed in many countries.
1.2 Agriculture - Shifted Cultivators
'Shifted cultivators' is the term used for people who have moved into rainforest areas and established small-scale farming operations. These are the landless peasants who have followed roads into already damaged rainforest areas. The additional damage they are causing is extensive. Shifted cultivators are currently being blamed for 60% of tropical forest loss (Colchester & Lohmann).
The reason these people are referred to as 'shifted' cultivators is that most of them people have been forced off their own land. For example, in Guatemala, rainforest land was cleared for coffee and sugar plantations. The indigenous people had their land stolen by government and corporations. They became 'shifted cultivators', moving into rainforest areas of which they had no previous knowledge in order to sustain themselves and their families (Colchester & Lohmann).
Large-scale agriculture, logging, hydroelectric dams, mining, and industrial development are all responsible for the dispossession of poor farmers.
"One of the primary forces pushing landless migrants into the forests is the inequitable distribution of agricultural land" (WRI 1992, Colchester & Lohmann). In Brazil, approximately 42% of cultivated land is owned by a mere 1% of the population. Landless peasants make up half of Brazil's population (WRM).
Once displaced, the 'shifted cultivators' move into forest areas, often with the encouragement of their government. In Brazil, a slogan was developed to help persuade the people to move into the forests. It read "Land without men for men without land" (WRM).
After a time, these farmers encounter the same problems as the cash crop growers. The soil does not remain fertile for long. They are forced to move on, to shift again, going further into the rainforest and destroying more and more of it.
It is evident that the shifted cultivators "have become the agents for destruction but not the cause" (Westoby 1987: Colchester). Shifted cultivators do not move into pristine areas of undisturbed rainforests. They follow roads made principally for logging operations. "Shifted cultivators are often used by the timber industry as scapegoats" (Orams and McQuire). Yet logging roads lead to an estimated 90% of the destruction caused by the slash-and-burn farmers (Martin 1991: Colchester).
Solutions: Land reform is essential if this problem is to be addressed. However, according to Colchester and Lohmann, "an enduring shift of power in favour of the peasants" is also needed for such reforms to endure (Colchester &Lohmann).
1.3 Agriculture - Cash Crops and Cattle Ranching
Undisturbed and logged rainforest areas are being totally cleared to provide land for food crops, tree plantations or for grazing cattle (Colchester & Lohmann). Much of this produce is exported to rich industrialised countries and in many cases, crops are grown for export while the local populace goes hungry.
Due to the delicate nature of rainforest soil and the destructive nature of present day agricultural practices, the productivity of cash crops grown on rainforest soils declines rapidly after a few years.
Monoculture plantations - those that produce only one species of tree or one type of food - on rainforest soil are examples of non-sustainable agriculture.
They are referred to as cash crops because the main reason for their planting is to make money quickly, with little concern about the environmental damage that they are causing.
Modern machinery, fertilisers and pesticides are used to maximise profits. The land is farmed intensively. In many cases, cattle damage the land to such an extent that it is of no use to cattle ranchers any more, and they move on, destroying more and more rainforest. Not only have the forests been destroyed but the land is exploited, stripped of nutrients and left barren, sustaining no-one.
Solutions:"Reducing the demand for Southern-produced agribusiness crops and alleviating the pressure from externally-financed development projects and assistance is the essential first step" (Colchester and Lohmann).
1.4 Fuelwood
The United Nation's Food and Agriculture Organisation estimates that '1.5 billion of the 2 billion people worldwide who rely on fuelwood for cooking and heating are overcutting forests'. This problem is worst in drier regions of the tropics. Solutions will probably involve a return to local peoples' control of the forests they depend on.
1.5 Large Dams
In India and South America, hundreds of thousands of hectares of forests have been destroyed by the building of hydro-electric dams. It was the dominant view that new dams had to be built or otherwise these countries would suffer an energy crisis. However, a recent study by the World Bank in Brazil has shown that 'sufficient generating capacity already exists to satisfy the expected rise in demand for power over the medium term, provided that the energy is used more efficiently' (WRM).
The construction of dams not only destroys the forest but often uproots tens of thousands of people, destroying both their land and their culture. The rates of waterborne diseases increase rapidly. Downstream ecosystems are damaged by dams which trap silt, holding back valuable nutrients. Reduced silt leads to coastal erosion. The sheer weight of water in dams has in Chile, Zimbabwe, and Greece led to earthquakes. The irrigation and industrial projects powered by dams lead to further environmental damage. Irrigation leads to salination of soils and industry leads to pollution.
Solutions: Aid organisations like the World Bank have traditionally favoured spectacular large-scale irrigation and hydro-electric projects. In all cases when such projects are proposed, there has been massive opposition from local people. Reform of the World Bank and other such organisations, and support for campaigns against large-scale dams is needed.
1.6 Mining and Industry
Mining and industrial development lead to direct forest loss due to the clearing of land to establish projects. Indigenous people are displaced. Roads are constructed through previously inaccessible land, opening up the rainforest. Severe water, air and land pollution occurs from mining and industry.
Solutions: Local campaigns against mining and industrial development, and the campaigns to reform the large aid agencies which fund such schemes, should be supported.
1.7 Colonisation Schemes
Governments and international aid agencies for a time believed that by encouraging colonisation and trans-migration schemes into rainforest areas, they could alleviate some of the poverty felt by the people of the financially poorer countries. It has since become increasingly obvious that such schemes have failed, hurting the indigenous people and the environment (Colchester & Lohmann).
These schemes involve the relocation of millions of people into sparsely populated and forested areas. In Indonesia, the Transmigrasi Program, begun in 1974, is believed to be 'the greatest cause of forest loss in Indonesia', directly causing an average annual loss of 200,000 hectares (Colchester & Lohmann).
The resettled people suffered the same problems as 'shifted cultivators'. The soil is not fertile enough to be able to sustain them for very long.
Even after such projects have officially ended, the flow of 'shifted cultivators' continues as the area remains opened up. "The World Bank estimates that for every colonist resettled under the official transmigration project, two or more unofficially move into the forest due to the drawing effect of the program" (Colchester & Lohmann).
1.8 Tourism
The creation of national parks has undoubtedly helped to protect rainforests. Yet, as national parks are open to the public, tourism is damaging some of these areas.
Often, national parks are advertised to tourists before adequate management plans have been developed and implemented. Inadequate funding is allocated for preservation of forests by government departments. Governments see tourism as an easy way to make money, and therefore tourism is encouraged whilst strict management strategies are given far less government support.
Ecotourism, or environmentally friendly tourism, should educate the tourists to be environmentally aware. It should also be of low impact to its environment. Unfortunately, many companies and resorts who advertise themselves as eco-tourist establishments are in fact exploiting the environment for profit.
In Cape Tribulation, Australia, for example, the rainforest is being threatened by excessive tourism. Clearing for roads and pollution of waterways are two of the major problems in this area. The Wet Tropics Management Authority which oversees the surrounding World Heritage Area is promoting tourism to the area before any management plans have been formulated, before any effective waste management strategy has been devised and before any ecofriendly power alternatives have been fully explored.
Solutions: The rights of indigenous forest dwellers and others who depend on intact forests must be upheld. In instances where there are campaigns opposing specific tourist developments, they should be supported. Genuine ecotourism should be preferred to other tourist enterprises.
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Saturday, October 31, 2009
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