Your readers may wish to speculate why oil depletion is discussed most openly by executives no longer in post.

ECONOMIST: Developing solutions

The Ehrlichs are correct that some trends deserve worry: soil erosion, degradation of tropical forests, fish depletion, the loss of farmland, to mention some of the most serious.

ECONOMIST: Green plus red-tape makes brown

Canadian's oil and gas trusts typically pay out most of their cash flow (net income plus noncash charges like depletion) to unit holders.

FORBES: Out of Energy

The main reason behind the depletion of the Ozone layer is industrial pollution which is produced by some of the world most industrialized states.

FORBES: Global Warming And Africa's Future: Part 2

"My position is to reconsider our current position in light of the most recent scientific data to ensure that the current position that Palau takes will not lead to the depletion and extinction of whales, " he said.

BBC: Palau pioneers 'shark sanctuary'