I agree with Medieval Guy, the first scene is my favourite! That waterfall is impressive, I can't remember seeing those transparent bricks used at an angle, it makes the waterfall even more realistic. The tree from the second scene is interesting, i might borrow that technique sometime!
I really think that bridge is neat. A very interesting way to suspend it. The second one has a great pine tree in the bottom corner, and I really like the cobblestone technique you used in the third one. That particular technique seems to be quite popular lately.