In 1995, it was estimated that (natural, "semi-natural" and planted) forests covered an area of 3.454 billion ha, that is some 26.6 percent of the total land mass (excluding Greenland and Antarctica); in 1990, other "wooded areas" (areas of bush, scrubland, heath, fallow land, etc.) covered an additional 1.68 billion ha. About 57 percent of the world's forests ( 1.961 billion ha) were in developing countries where the proportion of forest cover was the same as in the developed world (with 1.493 billion ha of forest) and therefore the same worldwide. Forests in temperate and boreal regions were a little less extensive (48.5 percent of the total land mass) than those of the humid and dry tropics. More than two-thirds of the world's forests were in seven countries: the Russian Federation, Brazil, Canada, the United States, China, Indonesia and former Zaire, in descending order. In 29 countries (including 21 tropical countries), more than half the land was covered by forest; while the proportion given over to forestry was less than 10 percent in 49 other countries (mainly small, unwooded, island states and territories) and in several entire subregions, including Saharan Africa (7.5 percent), non-tropical southern Africa (6. 8 percent), the Near East ( 1.9 percent) and North Africa ( 1.2 percent).
Natural forests cover a negligible area in Europe, significant areas in the rest of the developed world and the majority of the humid tropical countries (dense forests). These are forests which have not been used for production or silviculture (unlike the so-called "semi-natural" forests) and which are generally characterized by a complex structure, a range and allocation of species that are unique to the site, a wide range of ages and the presence of dead or dying trees.
Although it is often difficult to distinguish plantations from other forests in the developed world, they cover an estimated total of about 80 million to 100 million ha. In 1995, their estimated total area in developing countries was about 81 million ha, more than 80 percent of which were in the Asia and the Pacific region and more than 40 percent in China alone (which was followed in importance by India, Indonesia, Brazil, Viet Nam, the Republic of Korea and Chile, each with more than I million ha of plantation). In tropical countries as a whole, the proportion of large industrial plantations has decreased in favour of afforestation at village, farm and agroforestry levels, especially in the Asia and Pacific region (some of this new forestry supplies the industrial wood markets); three genera (eucalyptus, pines and acacias) and one species (teak) account for about half of all plantations. To complete the list of trees that are planted, "non-forestry" plantations should also be mentioned; these include rubber plants, oil- and coconut palms in tropical countries, as well as the trees used along hedgerows, the sides of roads and in urban gardens. Although these trees are only partially registered or not registered at all, they contribute (to a greater or lesser extent, depending on the country) to the production of forest goods and resources.
From 1990 to 1995, the area covered by forests (including plantations) in industrialized countries (excluding the Russian Federation) increased annually by about 1.75 million ha ( 0.39 million ha were in Europe and 0.76 million in North America). At the same time the area covered by natural or semi-natural forests in developing countries decreased every year by 13.7 million ha (12.9 million ha of which were in the tropics). This reduction was partly compensated by the 0.7 million ha planted every year (0.3 million ha in tropical countries), but the net annual reduction in forests was still 13 million ha. Every year during this period, the earth lost a total of 56.3 million ha of forest (equivalent to an area the size of France), that is 0.33 percent of total forest cover (or I percent every three years), with the annual loss in developing countries being 0.65 percent.
The FAO study on changes to tropical forest stands in the 1980s (FAO, 1996) has made it easier to identify the deforestation processes and factors in that part of the world. For example, the study showed that 40 percent of the dense tropical forest converted to other uses was completely cleared, mainly for agriculture and animal breeding, 10 percent was partially cleared or "fragmented" for the same reasons, 26 percent was transformed into bush for nomadic agriculture with short fallow periods, 20 percent transformed into light or mosaic forest for nomadic agriculture with long fallow periods, and 4 percent was converted into agricultural or forestry plantations. It is obvious that the various forms of agriculture - permanent with annual crops or perennial plantations. or nomadic with long or short periods of fallow - are the main deforestation factors in tropical countries, where most deforestation in developing countries takes place ( 12.9 million of the total 13.7 million ha deforested each year). The interaction of forests and agriculture is at the heart of the deforestation problem and preliminary solutions lie in finding a better way of integrating conservation and forest exploitation in rural development
