Environment, 2/e is a serious science text that is appealing and understandable to students from all disciplines. It takes a solutions-oriented approach to environmental problems by providing students with information and allowing them to make their own conclusions.
I use this textbook for my intro to environmental studies class - it does an excellent job providing a blend of basic science, environmental law, and public policy. It's too expensive, but what are you gonna do...
This is a textbook. It's a great non-partisan contemporary review of the state of physical ecology, and the effects man's modern lifestyle has had on the earth.
The worst part about this textbook (other than the utterly depressing content but that's okay) is the formatting and how all the headers look the same, which makes it really hard to take notes on. Of course, I think that's just a personal problem. What sucks the most about the class I had to get this book for was I read the whole textbook and the prof doesn't even make us use it. Ugh.