What is the theme in The Everglades: River of Grass by Marjory Stoneman Douglas?

Another theme of the book is the effect of modernization and the problems that it brought to the Everglades. When the various Indian tribes arrived, they adapted their customs and culture to the environment of the Everglades. They didn't try to change the Everglades. The Indians just adapted to the environment they were in. This wasn't true of the white man as Florida became more settled. They tried to change the Everglades.