Facts101 is your complete guide to Essential Environment, The Science Behind the Stories. In this book, you will learn topics such as Environmental Systems: Chemistry, Energy, and Ecosystems, Evolution, Biodiversity, and Population Ecology, Species Interactions and Community Ecology, and Human Population plus much more. With key features such as key terms, people and places, Facts101 gives you all the information you need to prepare for your next exam. Our practice tests are specific to the textbook and we have designed tools to make the most of your limited study time.