In nine volumes, explores each of the earth's major ecological regions, defining important features, animals, and environmental issues.

v. 1. The Polar regions -- v. 2. Deserts -- v. 3. Oceans -- v. 4. Wetlands -- v. 5. Mountains -- v. 6. Temperate forests -- v. 7. Tropical forests -- v. 8. Temperate grasslands -- v. 9. Tropical grasslands.