Trees cover over 25% of the Earth's land surface, and more than half of the forested resources are tropical. All over the world forests are being destroyed or degraded as a result of human activities including wood for fuel, building, foods and medical purposes, agricultural, livestock, strip mining and urban land needs, as well as pollution, warfare and population pressure. Over a third of Europe's remaining forest have been harmed to varying degrees by air pollution, soil acidification and disease. Similar damage is common in North America and East Asia. It had been estimated that the areas being deforested each year amount to at least 17 million hectares, while areas that are planted are only 1,150 thousand hectares (a ratio estimated by the FAO to be less than 11:1). Japan, Europe and the USA consume 66 million cubic metres of tropical hardwood a year. That is a 1500% increase in the past 30 years. This loss has immense wide ranging effects which include loss of biodiversity and human groups from forested areas, and disruptions to the water and atmospheric cycles in the form of increased flooding, landslides, soil erosion, droughts and the risk of global warming, as well as decreased purification, oxygen enrichment and carbon dioxide (CO2) extraction of the air. Deforestation may be considered as one of the gravest environmental crises facing the planet, and is hence relative to the importance of countering it.
There are two main forms of unsustainable development affecting forest lands. The first of these is wood extraction harvested and sold, usually for export. Such harvesting is typically carried out by bulldozers, in part to save money and realize higher profits, and partly because of the very density of a tropical rain forest. In contrast to the selective cutting done in temperate forests, timber harvesting in tropical rain forests usually leaves a barren landscape that has no chance to regenerate itself. The second threat to the rain forest comes from attempts to convert it to agricultural uses, ranging from small single-family farms to vast cattle ranches run by multinational corporations. Because the nutrients in a tropical rain forest are held mostly in the foliage, these efforts, too, soon leave behind an empty and lifeless terrain. Topsoil in the rain forest is very thin and must be held in place by trees and other forest plants; when those are cleared away the land rapidly becomes eroded, hard and rocky, unsuitable for continued ranching or farming.
This strategy features in the framework of Agenda 21 as formulated at UNCED (Rio de Janeiro, 1992), now coordinated by the United Nations Commission on Sustainable Development and implemented through national and local authorities.
The Peruvian Society for Conservation of Nature (APECO), and the regional government of the San Martin region of Peru, have initiated a strategy to control deforestation, conserve biodiversity, and provide a more integrated framework for APECO's work in environmental awareness and education. A joint project has been set up to conserve mountain forests in the region.
In Somalia, hundreds of square kilometres of trees are cleared every month by the charcoal industry. The Somali Environmental Protection and Anti-Desertification Organization (SEPADO) led a campaign to enhance environmental awareness of environmental destruction. It distributes T-shirts carrying the message "Environmental protection is the responsibility of every society member". Stickers are also distributed saying "Protect the environment", "My property does not take part in the destruction of our environment", "He who destroys the environment destroys human life" and "Don't exchange your beautiful forest for a handful of dollars".
Promoting intensive cash-crop industrial farming techniques, in which the overuse of fertilizers and the broadcast use of pesticides replace more ecologically sound food-crop agriculture, is another form of exploitation – and one of the chief generators of the displaced peasants that themselves then become a major cause of deforestation.
Policies of the World Bank and the IMF have had a devastating impact on the environment. After granting Nicaragua a loan in 1994, the IMF supported the expansion of the logging industry, causing an increase in Nicaragua's already high rate of deforestation (370,000 acres/year). At this rate, the few forests that remain in Nicaragua will disappear quickly.
In 1997, a World Bank proposal to double the royalties charged by the Indonesian government to concessionaires cutting down state-owned timber was rejected by the forestry minister saying it would only encourage Indonesians to go after cheap, illegally cut timber.