Philip Hart wrote: >Anybody know anything about agriculture? I can vaguely imagine that >it's possible to fix nitrogen in the soil by sorcery, but I can't see >how the (pre-Interregnum) Empire could do that on many millions of >acres multiple times per generation. And I think that doesn't help with >erosion. > > There are pretty well-known ways to keep soil in good condition: adding compost, rotating crops, using fallow field systems of various kinds, fertilizing with dead fish, marling, no-till cultivation, etc. You can deal with erosion by contour plowing, terracing, planting tough cover crops, etc. Whether these methods would stand up to 200ky or not I don't know, but they certainly work on a several thousand year span, and they predate the Industrial Revolution almost entirely. >And I certainly don't see how the calories the plants miss because of the >overcast can be replaced. > > > This one I don't understand. The caloric content of plants shouldn't vary with sunlight. Do you mean that there will be fewer calories available from plants because there will fewer plants? Snarkhunter