In the ongoing wars over ocean, forest, and green space, environmentalists often find themselves at a disadvantage. Timber barons in the Pacific Northwest, for example, can translate the benefits of clear-cutting into gains in profits and jobs.
Conservationists lack such precise numbers.
They are reduced to making broad assertions about the importance of trees in protecting endangered species or to issuing vague warnings about the danger of ignoring nature's contribution to human survival. Now, however, a group of scientists have put a price tag on nature's bounty, giving environmentalists the means to fight back in kind. Published in last week's Nature, their study is essentially a synthesis. Using results from previous small, site-specific efforts, as well as some original calculations, the researchers estimated the current economic value of 17 services provided by 16 types of ecosystems, including open ocean, deserts, forests, grasslands, and coastal habitats. They then multiplied the results by the area of the Earth's surface covered by each habitat.