Georg and Brenda Feuerstein, of Traditional Yoga Studies in Eastend, SK, have written a superb book that details how environmental consciousness can and should be incorporated into continuous practice by all who follow the Dharma.
They offer it to all as a free download:

We have chosen this option for two simple reasons: First, the environmental crisis is extremely severe, and green action is of the utmost urgency. We are hoping that our book might stimulate its readers into appropriate attitudinal change and responsible action. Publishing this book through regular channels would take too long to reach the public, as well as destroy a large number of trees and add to pollution. Second, we feel more comfortable with not charging for a book on the Buddha Dharma.

The price is right, and so is the speech and understanding. Give it a look.

http://www.traditionalyogastudies.com/green_dharma.html