Nature is for many people taken for granted - especially in everyday life. A Tree, a meadow is nothing special because there is still (fortunatelly) a lot around us. For that reason most of us do pass it day by day without recognizing its existence.

When the alleged matter of course is emphazised and marked as something precious to be protected, than there is a moment created to think about.
(A terrible image to walk through a park without green and a stinky poisened lake...)

The "Deutsche Bahn" can use that and indicate their own environmental program.