Not much contrast in this shot. The cigarette butt stands out the most, and I'm not sure that's a good thing. There's just no real subject in this photo. The little dead tree does not carry the pic, as the large cube shaped rocks really overtake it.
OK. I saw it like the (now dead) tree had broken through the cobblestones. A life and dead scenario. But now I think the tree was planted and the cobblestones removed on purpose. Bye-bye motive.
As far as contrast, I mean there are no lights/darks/varying colors in the shot. Everything's pretty much the same color and tone. Nothing there to break things up.