THE VALUE OF THE WORLDS ECOSYSTEM SERVICES AND NATURAL CAPITAL (REPRINTED FROM NATURE, VOL 387, PG 253, 1997)

The services of ecological systems and the natural capital stocks that produce them are critical to the functioning of the Earth's life-supp ort system. They contribute to human welfare, both directly and indire ctly, and therefore represent part of the total economic value of the planet. We have estimated the current economic value of 17 ecosystem s ervices for 16 biomes, based on published studies and a few original c alculations. For the entire biosphere, the value (most of which is out side the market) is estimated to be in the range of US$16-54 trillion (10(12)) per year, with an average of US$33 trillion per year. Because of the nature of the uncertainties, this must be considered a minimum estimate. Global gross national product total is around US$18 trillio n per year. (C) 1998 Elsevier Science B.V. All rights reserved.