Tropical forests are being destroyed at an ever-increasing rate. Estimates of the extent and rate of loss vary, but it appears that nearly half of the world?s tropical forests already have been lost, and the remainder will all but disappear in the next two to three decades. The loss is incalculable. These forests provide habitat for an estimated half of the world?s plant and animal species, provide water and fuel for much of the world?s population, and influence regional and global climate. Commercial logging, clearance for agriculture, ranching, and fuel gathering are all responsible for the destruction. Their greatest threat is acid rain pollution, which is already severely affecting large areas of the conifer forests of northeast North America and Europe. Solutions include the development of alternative fuel wood supplies through fuel wood plantations, the regulation of logging, and a consensus as to the value of forest conservation over commercial development.
Overgrazing and firewood gathering denude vast areas of arid lands, resulting in inexorable spread of deserts and desert like conditions. The United Nations estimates that, at present rate of loss, by the year 2000 about one-third of the world?s arable land will be nonproductive.