Posted by: bobbanner
on Aug 12, 2009
A CIVILIZATIONAL TIPPING POINT
http://www.earthpolicy.org/Books/Seg/PB3ch01_ss5.htm
Lester R. Brown
In recent years there has been a growing concern over thresholds or tipping points in nature. For example, scientists worry about when the shrinking population of an endangered species will fall to a point from which it cannot recover. Marine biologists are concerned about the point where overfishing will trigger the collapse of a fishery.
We know there were social tipping points in earlier civilizations, points at which they were overwhelmed by the forces threatening them. For instance, at some point the irrigation-related salt buildup in their soil overwhelmed the capacity of the Sumerians to deal with it. With the Mayans, there came a time when the effects of cutting too many trees and the associated loss of topsoil were simply more than they could manage.