Global warming and human-driven impacts are changing the World's ecological zones. This book applies the principles described in Bailey's Ecosystem Geography: From Ecoregions to Sites, 2nd ed. (Springer 2009, 1st ed. 1996) to describe and characterize the major terrestrial and aquatic ecological zones of the Earth. Bailey's system for classifying these zones has been adopted by major organizations such as the U.S. Forest Service and The Nature Conservancy and this book is a significant contribution to a long tradition of classifying and studying the world's ecological regions or ecoregions. It includes two color maps that show the major ecoregions of the continents and oceans. Also included are: - 106 illustrations with 55 in full color - A new chapter on mountains is included. - There are new sections that address concerns about how eco regions are changing under the relentless influence of humans and climate change - Another new feature is the discussion of using eco regional patterns to transfer research results and select sites for detecting climate change effects on ecosystem distribution - Use of ecoregional patterns to design monitoring networks and sustainable landscapes - Fire regimes in different regional ecosystems and their management implications.