Alright, now that it's fixed:
First thing i'm noticing is it feels unfinished. Nothing has any texture of note, the colors are somewhat flat, and in general it needs a lot of touching up.
Second is there's no sense of scale and the composition is a bit off for what I'm assuming you're going for, IE, tree-and-bridge-on-a-cliff. The background trees (?) crowd around that cliff edge too much, try lowering them so that cliff is more out in the open and has a clearer silhouette.
Also, what's the big thing on the left? A rock? A sand dune? Another tree? it needs some work to be clear.
Finally, try and fade out the clouds some so they fit into the background more. They're too saturated as they are now, meaning they compete for attention with more important objects like that cliff edge.
It's a good rule of thumb, the more far back in the image something is supposed to be the less saturated you want it!
