I hope you have kept your debug.err, SD needs that file for some of these bugs, I have loaded your game and it seems some where your files or such are corrupt, and the farms are listing as producing arcane, as can bee seen in the bellow pic on the right hand page of the book entry(30% bonus to arcane)
A few pics, a save from my computer and a debug.err are posted here.
Have you installed any mods? if so try removing them, if that doesn't work, then im not sure if their is an easy way other then deleting all your xml files and reinstalling them.
