Overview
Although public awareness of the impact of global deforestation has increased in recent years, it has not slowed the rate of deforestation appreciably. A comprehensive assessment of the state of the world’s forests, recently released by the Food and Agriculture Organization of the United Nations (FAO), indicates that total forested area continues to decline significantly. According to the FAO analysis, deforestation was concentrated in the developing world, which lost nearly 200 million hectares between 1980 and 1995. This loss was partially offset by reforestation efforts, new forest plantations, and the gradual regrowth and expansion of forested area in developed countries. The result was a net loss of some 180 million hectares between 1980 and 1995, or an average annual loss of 12 million hectares [1].
According to FAO, the rate of deforestation dropped slightly during its last survey period. Between 1990 and 1995, annual forest loss in developing countries was estimated at 13.7 million hectares. This rate compares with a rate of 15.5 million hectares annually between 1980 and 1990 [2]. (See Forest Loss is Severe in the Tropics.) This small decline is largely due to reported decreases in the deforestation rate in the Amazon in the early 1990s. Even this small decline is disputed by some forest experts, who regard FAO’s calculations for 1990 to 1995 as underestimates [3].
In any case, there is no dispute that deforestation rates remain high in many countries; indeed, in the majority of countries that FAO surveyed, deforestation rates have actually increased. In addition, evidence from other sources suggests that deforestation rates in some important regions have increased since the assessment.
In the Brazilian Amazon, for example, the annual deforestation rate declined from a peak of more than 20,000 square kilometers in 1988 to just over 11,000 square kilometers in 1991. However, newly released data from the Brazilian Government show that it rebounded to more than 29,000 square kilometers in 1995 before declining to 18,100 square kilometers in 1996 [4]. (See Amazon Deforestation Rate Remains High.) Official estimates of Amazon deforestation in 1997 are not available yet, but there are indications that the deforestation rate may have risen again. Satellite data for the Amazon region show a 50-percent increase from 1996 to 1997 in the number of forest fires set by farmers to clear land for cultivation or pasture. Many of the fires are set to clear old cattle pastures or secondary forest areas, but about one third of the fires are set to clear virgin forest and thus represent one of the principal means of deforestation in the region [5].
Fire-related deforestation also rose sharply in Indonesia in 1997, as severe drought conditions helped spread fires set by plantation workers and farmers into forest areas. Preliminary estimates of the forest area destroyed run from 150,000 to 300,000 hectares [6]. Although most of the burning took place in secondary forests rather than virgin rainforest, the impact has nonetheless been high, destroying habitat for a variety of wildlife species from orangutans to tigers. The fires may increase pressure on adjacent virgin forests by increasing access to formerly remote sites [7].
The FAO analysis concludes that the leading causes of deforestation are the extension of subsistence farming (more common in Africa and Asia), and government-backed conversion of forests to other land uses such as large-scale ranching (most common in Latin America and also Asia). Poverty, joblessness, and inequitable land distribution, which force many landless peasants to invade the forest for lack of other economic means, continue to drive forest clearance for subsistence farming in many regions. Often, people move into forest areas as logging activity creates roads that open formerly inaccessible regions. As for centrally planned forest conversion schemes, these are often used to spur short-term economic development, gain better political control of remote forest regions, and expand agricultural output [8].
The state of the world’s forests is not simply a matter of their extent. Increasing attention is focused upon the health, genetic diversity, and age profile of forests, collectively known as forest quality. Measures of total forest area do not reveal the degraded nature of much regrowth forest. For example, in FAO’s forest assessment, logging is not counted as deforestation, since logged-over areas can, in theory, regrow to fully functioning forests. But logging often does degrade forest quality, inducing soil and nutrient losses and reducing the forest’s value as habitat. Logging pressures in many of the remaining large, virgin rainforest areas continue to increase, with logging activities shifting from the largely deforested areas of Southeast Asia to the rainforests of the Amazon region, Papua New Guinea, and the Congo Basin.
References and notes
1. United Nations (U.N.) Population Division, World Population Prospects 1950-2050 (The 1996 Revision), on diskette (U.N., New York, 1996).
2. Ibid.
3. Op. cit. 1.4. United Nations (U.N.) Population Division, World Population Prospects 1950-2050: The 1996 Revision, Annex 1: Demographic Indicators (U.N., New York, 1997), pp. 11-45.
5. Ibid., p. 121.
6. Op. cit. 4, pp. 124-125.
7. Op. cit. 1.
8. Op. cit. 4, Table A.18, pp. 120-122.
