The photo you posted is too small to tell anythig. If you want people to help, you need to post the full size image.
Agree with Madscica-- The lower half looks to be underexposed. Not sure of your ISO and aperture settings. Personally, I try to use 100 ISO and F/11 to F/16 on most of my landscapes thus a tripod is used often. 14-24mm lens as well for a good wide angle.