If you want to find out how complex the relationship between ecology, water resources and human food supplies is becoming, check out this item on Endangerd Species Act Ruling and food production in California. In order to even grasp the players in this scenario one has to gain some altitude and look at it systemically. It is interesting that nowhere in the article is there an exploration of the assumptions about the rights of humans to populate requiring the responsibility of understanding the carrying capacity of the eco-region for all life. This article seems locked into post-modern (green) worldviews of entitlement.

http://brianallmerradionetwork.wordpress.com/2010/01/05/01-05-10-endangered-species-act-ruling-threatens-food-production-in-california/