Re: Soil loss through erosion (from Usenet, sci.environment)
Subject: Topsoil loss
Date: 24 Apr 92 20:29:43 GMT

From SCIENCE's "Random Samples" department (3 April 1992, p. 28):

 Around the world, fertile soil is rapidly washing away or becoming
 dust in the wind.  So goes a global assessment of soil conditions
 released last month by the World Resources Institute (WRI) and hailed
 by the Washington, D.C., think tank as the first of its kind.  Said
 WRI president Gus Speth at a press conference releasing "Toward
 Sustainable Development," this "confirms our worst fears" about the
 degradation of arable land since World War II.

 The data were produced from a 3-year-study sponsored by the United
 Nations Environmental Program, in which hundreds of experts compared
 contemporary conditions with those tracked over the last 45 years.
 The report concludes that more than 3 billion acres of fertile land --
 an area the size of China and India combined -- have been seriously
 degraded, mainly because of overgrazing, damaging agricultural
 practices, and deforestation.  In the Indian state of Uttar Pradesh in
 the Ganges Valley, for example, alkalinity, salinity, and waterlogging
 have squeezed 29% of cropland out of production.

 Speth calculates that the world's nations may have to triple food
 production in the next 50 years to keep up with population growth.
 Crop rotation and other on-farm practices will remedy mild soil
 degradation, but national programs are needed, the report says, for
 large-scale soil conservation and watershed management projects.
 Supporting its sense of urgency, WRI printed its report early in hopes
 of influencing the negotiations over worldwide environmental treaties
 that are preceding the United Nations Conference on the Environment
 and Development, to be held in Rio de Janeiro in June.