Concept A:
A hand digs into a bag of soil and ashes. The grains sift through the fingers and fly in the wind.
The art would be strange. This would work better for a sorcery but it doesn't sound so good now.
Concept B:
A wizard holds a globe which is actually a puzzle. Odd puzzle pieces attach themselves onto the globe.
This has the capacity for some interesting art but it might look like ****e. Possibly.
Concept C:
An hourglass with a destroyed forest in the top chamber and a beautiful lush forest in the bottom chamber.
This actually seems pretty good to me, although people will of course complain if it's just forests.
Concept D:
A jewel hovers in front of a desert. Through the jewel the desert appears as a different type of landscape through each of its facets.
Interesting idea.
Concept E:
A mirror in which the reflections of dead trees and plants appear living.
So what's a mirror doing standing in the middle of nowhere? The artist could make it a cool looking mirror, but with the art coming out of WotC these days, that won't happen. Besides, swamps have dead stuff in them, right? Can't you bring back swamps?
Concept F:
An artist paints a picture of a landscape; the landscape alters to match the painting.
I have no idea how I'd express this concept...
Concept G:
An old-style plow cutting through plain worn dirt. Prosperous land full of life forms in the cut behind.
Woot, plow.
Concept H:
A mysterious floating pyramid hovers above a barren wasteland. Tools and implements come out of the bottom, tilling, watering and fertilizing the land beneath.
This looks pretty cool. I just hope the pyramid doesn't get so big that they decide to make it cost more for no reason.
Concept I:
A sundial with depictions of the five lands, colors, or elements around the dial. The setting should be pastoral.
This is interesting but doesn't really say what will happen to the land.
Concept J:
A mechanical tree clings to a scorched wasteland. Clockwork roots repair the soil, and metal leaves radiate life.
This is interesting but it would be better if it were an artifact creature. Oh well.
I vote H.