Large scale agriculture will add up, until someday it doesn't. This fable told by Jeremy Grantham explains it quite well.
<i>My favourite story is about the contract between the farmer and the devil. The devil says, "sign this contract and I'll triple your farm's profits". But there are 25 footnotes, as there always is with the devil. Footnote 22 says that 1% of your soil will be eroded each year, which is actually horrifyingly close to the real average over the past 50 years. The farmer signs and makes a fortune on a 40-year contract. And his son then signs up for the next 40-year contract and makes a fortune. And his son then signs up for the third and final contract. He still does very well, and in the final 20 years the family has accumulated enormous wealth, but the soil has gone. It's the same story for all his neighbouring farms and everyone is out of business. My sick joke is that at least he will die a rich farmer when all the starving hordes arrive from the city.</i>
<i>My favourite story is about the contract between the farmer and the devil. The devil says, "sign this contract and I'll triple your farm's profits". But there are 25 footnotes, as there always is with the devil. Footnote 22 says that 1% of your soil will be eroded each year, which is actually horrifyingly close to the real average over the past 50 years. The farmer signs and makes a fortune on a 40-year contract. And his son then signs up for the next 40-year contract and makes a fortune. And his son then signs up for the third and final contract. He still does very well, and in the final 20 years the family has accumulated enormous wealth, but the soil has gone. It's the same story for all his neighbouring farms and everyone is out of business. My sick joke is that at least he will die a rich farmer when all the starving hordes arrive from the city.</i>
https://www.theguardian.com/environment/blog/2013/apr/16/jer...