[an error occurred while processing this directive] Imperiled Riches—Threatened Rainforests [an error occurred while processing this directive] Amazon clear-cutting in Peru. (Photo by R. Butler) [an error occurred while processing this directive] [an error occurred while processing this directive] A WORLD Imperiled: FORCES BEHIND FOREST LOSS [an error occurred while processing this directive] As the first seven sections of this site have described, tropical rainforests are incredibly rich ecosystems that play a fundamental role in the basic functioning of the planet. Rainforests are home to probably 50 percent of the world's species, making them an extensive library of biological and genetic resources. In addition, rainforests help maintain the climate by regulating atmospheric gases and stabilizing rainfall, protect against desertification, and provide numerous other ecological functions.

[an error occurred while processing this directive] However, these precious systems are among the most threatened on the planet. Although the precise area is debated, each day at least 80,000 acres (32,300 ha) of forest disappear from Earth. At least another 80,000 acres (32,300 ha) of forest are degraded. Along with them, the planet loses as many as several hundred species to extinction, the vast majority of which have never been documented by science. As these forests fall, more carbon is added to the atmosphere, climactic conditions are further altered, and more topsoil is lost to erosion.

Despite increased awareness of the importance of these forests, deforestation rates have not slowed. Analysis of figures from the Food and Agriculture Organization of the United Nations (FAO) shows that tropical deforestation rates increased 8.5 percent from 2000-2005 when compared with the 1990s, while loss of primary forests may have expanded by 25 percent over the same period. Nigeria and Vietnam's rate of primary forest loss has doubled since the 1990s, while Peru's rate has tripled.

	Rate of change in total deforestation rate 2000-2005 period vs 1990-2000 period
	Country		Rate of change (%)
	Malaysia		85.7
	Cambodia		74.3
	Burundi		47.6
	Togo		41.6
	Nigeria		31.1
	Sri Lanka		25.4
	Benin		24.1
	Brazil		21.2
	Uganda		21.0
	Indonesia		18.6
	Total (62 tropical countries)		8.5

Overall, FAO estimates that 10.4 million hectares of tropical forest were permanently destroyed each year in the period from 2000 to 2005, an increase since the 1990-2000 period, when around 10.16 million hectares of forest were lost. Among primary forests, annual deforestation rose to 6.26 million hectares from 5.41 million hectares in the same period. On a broader scale, FAO data shows that primary forests are being replaced by less biodiverse plantations and secondary forests. Due to a significant increase in plantation forests, forest cover has generally been expanding in North America, Europe, and China while diminishing in the tropics. Industrial logging, conversion for agriculture (commercial and subsistence), and forest fires—often purposely set by people—are responsible for the bulk of global deforestation today.

Deforestation figures and charts

• Tropical Deforestation Rates [sortable]
• Primary Forest Deforestation Rates [sortable]
• Country by Country Deforestation Rates
• Deforestation Pictures
  
  Recent deforestation news articles
• Amazon deforestation slows in Brazil for 2005 December 5, 2005
• Nigeria has worst deforestation rate since 2000 November 17, 2005
• World deforestation rates and forest cover statistics, 2000-2005 November 16, 2005

But enough about the extent and some of the effects of deforestation. What is responsible for this loss? This is the question this section addresses.

Deforestation and Degradation

Before expanding further on forest loss it is critical to first explain what is considered "forest" and what is meant by deforestation and forest degradation.

The Food and Agriculture Organization of the United Nations (FAO), the leading source for information on the status of the world's forests, defines forests as land with a tree canopy cover of more than 10 percent and an area of more than half a hectare. FAO says that "forest" includes natural forests and forest plantations but specifically excludes stands of trees established primarily for agricultural production (i.e. fruit tree and oil palm plantations) and trees planted in agroforestry systems.

Other organizations use different standards for defining forests. For example, the United Nations Environment Programme (UNEP) uses 40 percent cover as the threshold for "closed forests" and 10-40 percent cover for "open forests," while the Tropical Ecosystem Environment Observations by Satellite (TREES) project—funded in the 1990s by the European Commission—classifies areas with more than 70 percent canopy cover as "dense forests" and those with 40-70 percent cover as "fragmented forest."

To reduce confusion, this site will generally follow FAO's convention, even though it has been criticized for its generous definition of what it considers forest.

FAO defines deforestation as "the conversion of forest to another land use or the long-term reduction of the tree canopy cover below the minimum 10 percent threshold." Depletion of forest to tree crown cover greater than 10 percent (say from 90 percent to 12 percent) is considered forest degradation. Logging most often falls under the category of forest degradation and thus is not included in FAO deforestation statistics. For this reason, forest degradation rates are considerably higher than deforestation rates.

Digging a little deeper, FAO says that "deforestation includes areas of forest converted to agriculture, pasture, water reservoirs and urban areas," but the term "specifically excludes areas where the trees have been removed as a result of harvesting or logging and where the forest is expected to regenerate naturally or with the aid of silvicultural measures."

Deforestation vs. Degradation

Causes of Deforestation Clear-cutting for logging and pulpwood Forest conversion for permanent agriculture (palm oil plantations, soybean fields) Large-scale shifting cultivation (i.e. slash-and-burn) where forest is not permitted to regenerate due to subsequent clearing Forest conversion for permanent pasture Open pit mining and large-scale mining operations Clear-cutting for charcoal production Large roads and infrastructure projects Wildfires that destroy the forest canopy Dam construction Volcanic eruptions Chemical defoliants Urban expansion

Causes of Degradation Most forms of logging for timber harvesting, especially "selective logging" Small-scale shifting cultivation (i.e. slash-and-burn) Over-grazing Small scale mining and associated pollution Over-harvesting for fuel wood Fragmentation from small roads Wildfires that burn leaf litter and small plants but leave canopy trees intact Over-harvesting of non-wood forest products (medicinal plants, foods, fibers) Over-hunting Invasive species Oil pollution Storm damage Extreme drought Air pollution and acid rain

[print version]
Review questions:

• What is the difference between deforestation and forest degradation?
• What are some examples of activities that cause deforestation?
• What are some causes of forest degradation?

Continued: Natural forces behind deforestation [an error occurred while processing this directive] [an error occurred while processing this directive] [an error occurred while processing this directive]