I hear what you say, but the reason that I single out farming is because that is the largest land use there is. There is forestry and mining, too, and as much as 0.2 per cent of the world's land surface is covered in homes and factories. But it is hard to get away from the fact that the total land area that humanity uses is reducing, while the global footprint people tell us that it is increasing.
The reason, as I posted in reply to Joseph, is that the representation of the footprint in area (hectares) is a fictictious device. (since then, I found the reference, it is on page four of the Global Footprint Atlas 2008, under methodology). When they tell each of us that our ecological footprint is 6.3 hectares, that is not any measure of land area at all, but the representation of notional resource availability, in subdivisions of a notional earth. Each of those 'more than 150' estimates carry all the inherent problems of confusing relative with absolute limits. Hence the absurdity of telling us that we are living on the proceeds of one and a half planets, when there is in fact only one.
Doug: "But this is like beating one's head against a wall, since you just don't want to believe any of this."
I share your frustration. It is beyond belief to me that you want to give a free pass to this kind of statistical manipulation, that you would not tolerate from economists for one moment.