I'm thinking Dawn and the School Spirit War as the most obvious example. Dawn isn't afraid to get vocal about things she finds faulty that's not only envirornment. I'd imagine that when she gets into enviornment, someone hands her leaflets about the ACLU and Darfur, and Dawn getting indignant and starting up protests.
I see Dawn as an environmentalist. I wouldn't be surprised if she got into government and try to get bills passed to protect the environment. I could also see her as a store owner and sell recyclable things as well as healthy foods.