Perhaps someone has done this before me, but if so, I did not find it around here.
In the map you will find terraces with crops. The example is in the south of the map.
This effect is created by elevations in 'stair formation'. Each stair is covered with shoreless water and bordered with Broken Road Fungus. This terrain type is necessary, I'm afraid, because it is the only one that adequately borders the shoreless water in stead of disappearing in it, like e.g. grass and dirt. The final stap consists of placing plants systematically along the edge of the water. For this one can use the tall grasslike plant from Jungle, or the tiny plants from the Gaia units (category 'Other').
For the plants to look like crops, they should be exactly the same. For this, one can create a patch of Jungle, copy it, click 'Turn Right' twice or so, and paste. Then there will be a patch full of the tall grass. Select a row and copy it (with the right elevation!) along the water.
This works best in straight lines. It can be used for Asian maps/scenarios and the water terraces can be combined perfectly with the Asian mill type.
Tsunami Studios: http://aok.heavengames.com/blacksmith/showfile.php?fileid=5748. In one of the files one can find a waterfall etc. I used the technique to create irrigation canals along the slopes of the terraces.
The several types (from sowing stages when building the farm) of farmland strips in the north are copied from someone who made this available somewhere in the Blacksmith, but I forgot the location.