Defining "natural" - When environmental groups speak about restoration, they typically note a reference point to give definition to the natural state they want to restore to. One common reference point is "Pre-European settlers." For example, we know that what we would have seen here 100 years ago is completely different from 500 years ago.
This measure of value for nature in terms of dollars has been happening for some time. Ecological Economists, Herman Daly and John Cobb wrote For the Common Good in 1989 about the economic value of our ecosystems. Glad to see Florida is catching up.
Puget Sound is one example where ecological economists determined that the near shoreline ecosystems produce an annual value of $140,000 per acre. This estimate of value is low due to the fact that the ecosystems have been compromised by nearby Superfund sites. How do I know this? I took an ecological economics course and the professor was one of the scientists that worked on this project.
By having solid numbers to work with, even greedy folks can be made to pay, one way or another.