Perhaps I should have waited to post on this question until I had an articulated response or perhaps, the question is simply rhetorical. Because, in the end, does it matter who we are motivated to save nature for, as long as it is being saved?
As always, it depends. Well first of all, this has actually turned into 3 questions so maybe I should focus my thoughts. With regard to the specific question of "WHO" this is the thought process I've has so far.
Individually, I think the answer is both. I feel a strong pull towards environmentalism because a) I want nature to be preserved and protected so that the human race can continue to survive. We all depend on the environment for every single aspect of our lives so logically, I would be motivated to protect that which gives me life; b) I want to protect the environment because I think all organisms have a right to survive and carry out their lives and share the planet with us. I guess that is a pretty diplomatic answer but if a major in Human Development has taught me anything, the answer to most questions is "both", it just matter which side is more dominant. This is a big question so there is still a lot more I need to think about.
As far as the general population of non-environmentalists, my guess is that people are motivated to save the environment because they want to save themselves in some way. Maybe that is a cynical view of the general public but that is where I'm at right now.
There is definitely more I will have to say on this topic so I plan on coming back to it in a later post. Until then...