THE WORLD ACCORDING TO PIMM

A biologist estimates the pace at which we’re depleting Earth’s resources, and the numbers he comes up with are grim.

Bottom line: human beings annually use more than 40 percent of the planet’s resources, and the population continues to grow. Pimm (Conservation Biology/Columbia Univ.) gives detailed descriptions of land-use practices in various areas. To many readers the mention of the Amazon rain forest calls up an unbroken vista of lush trees with exotic creatures lurking in the underbrush. But in a flight above the Amazon, the smoke of constant forest fires hides the trees. On the ground, the picture Pimm sees is even uglier: with the trees gone, the land can barely support a year’s worth of crops. The same story holds true in Africa and southern Asia. North America’s soil was originally deep enough so that when the farmers moved west to newer fields, second-growth forests were able to take root. But even in the better soil of the American heartland, a farmer seduced by two or three good years in a row can still be wiped out when the inevitable bad times arrive. Irrigation eventually leaves land unusable because of accumulated salts. Pimm holds up the saga of Easter Island as the ultimate ecological horror story. Its Polynesian settlers gradually destroyed the land and the trees; finally they had nothing to eat and no way to escape. And we are depleting the oceans almost as brutally as the land, the author adds. Not all is doom and gloom, but no reader is likely to go away thinking the environment can heal itself. Pimm concludes with a few practical suggestions for avoiding worldwide starvation. It is possible, he thinks, to have both food and nature—if we act before we find ourselves on our own Easter Island.

Sobering and compelling: a must-read.