But news of such loss on American soil, far from any foreign battlefield, has the power to shock.

NPR: Marines Killed In Training Were Young, Lives Ahead

The loss of the springs brought with it a loss of the natural filtration of soil and sand, however, so the Maya built their own primitive filtration systems, forcing their rainwater runoff through boxes of sand, the researchers found.

MSN: Sustainable tech saw the ancient Maya through drought

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

Water pollution, soil erosion, deforestation and desertification in the north, where rivers are drying up, have contributed to an estimated loss of one-fifth of agricultural land since 1949.

FORBES: Pollution And Prosperity