Rattan Lal & B.A. Stewart 
World Soil Resources and Food Security [PDF ebook] 

Soil-The Basis of All Terrestrial Life Ancient civilizations and cultures-Mayan, Aztec, Mesopotamian, Indus, and Yangtze-were built on good soils, surviving only as long as soils had the capacity to support them. In the twenty-first century, productive soil is still the engine of economic development and essential to human well-being. The quality of