Threats to forests and the increasing demand for timber

Global demands

The world's woodlands and forests have always changed in response to alterations in climate and the impact of animals, especially the grazers and disease organisms. The major difference in the present Flandrian interglacial is the overwhelming impact of humans, whose world population rose from under two billion in 1900 to over six billion in 2000, after having been comparatively negligible in Neolithic times. Accurate estimation of annual global wood consumption is difficult but it was at least 3.36 billion m3 in 1996, of which some 55% was used as fuel, largely in developing countries. The other 45% went for industrial use, largely as saw logs but also as chemical raw material. Sugar produced by trees in photosynthesis can be converted into a host of complex chemicals, then combined into a cellular structure with a high strength to weight ratio. Lignin, cellulose, resins, turpentine, wood alcohol and many other products are all derived from trees.

Twenty per cent of the world population lives in developed economies where consumption is high and the fertility rate (average number of children per woman) low; the remaining 80% exist in the so-called developing economies where consumption is low and the fertility rate may be as high as seven. Average use of wood per person per year in 1990 was around 2.3 m3 in the USA, nearly four times the 1996 global average of 0.58 m3.