http://en.wikipedia.org/wiki/Liebig's_Law_of_the_Minimum

It also seems to me industrial agriculture is more exposed to the Liebig's Law of the Minimum problem than are small farms close to urban areas.

Also, as I have repeatedly stated, the key problem regarding energy supplies, IMO, is net export capacity, especially net oil exports. The Saudis continue to assure the world that they can supply oil to the market for decades to come--while the volume of oil that they are actually delivering to the market has shown an accelerating annual decline rate from 2006 to 2007.

It occurs to me that there is a parallel between refineries and industrial food producers.

I have suggested a geometric progression in crude oil prices (per barrel) as importers bid for declining net oil exports:

$50, $100, $200, $400. . .

This results in a geometric progression in product prices (gasoline, diesel, jet fuel, etc., per gallon):

$2, $4, $8, $16 . . .

At each product price doubling, what happens to demand, i.e., the volume of product that consumers can and will buy?

As demand falls, it stands to reason that refinery operators, especially in importing countries, will curtail their refinery runs, in order to match their product output against declining demand.

As noted in the article, this is also the problem with the industrial agricultural model, where they have to match higher fuel and fertilizer costs against the demand for food products, i.e., what consumers can and will buy.

However, unlike petroleum products, consumers can, to some degree, do something about becoming closer to a net food producer.

My long time recommendations:

ELP Plan (April, 2007)
http://graphoilogy.blogspot.com/2007/04/elp-plan-economize-localize-prod...

A real life case history:

http://www.energybulletin.net/5673.html
Published on 22 Jul 2004 by San Francisco Chronicle. Archived on 25 Apr 2005.
Berkeley: Urban farmers produce nearly all their food with a sustainable garden in their backyard