Many of the world's ecosystems are in danger and might not support future generations unless radical measures are implemented to protect and revive them, according to the most comprehensive analysis ever conducted of how the world's oceans, dry lands, forests and species interact and depend on one another.
The new report collates research from many specific locales to create the first global snapshot of ecosystems. More than 1,300 authors from 95 countries participated in the Millennium Ecosystem Assessment, whose results are being made public today by the United Nations and by several private and public organizations.
"Only by understanding the environment and how it works, can we make the necessary decisions to protect it," said U.N. Secretary General Kofi Annan in a statement marking the report's release. "Only by valuing all our precious natural and human resources, can we hope to build a sustainable future."
The effort brought together governments, civil society groups, industry and indigenous people over a four-year period to examine the social, economic and environmental aspects of ecosystems.
The report was assembled by the U.N. Environment Program and included scientists from many universities and organizations, including the World Bank. Jonathan Lash, president of the nonprofit World Resources Institute, which helped put together the report, said it "created for the first time a set of leading ecosystem indicators."
Although food production is up, the report said, many other benefits that humans obtain from ecosystems are threatened, and some environmental changes can produce sudden, unexpected deteriorations in water quality, climate and health.
"Human actions are depleting Earth's natural capital, putting such strain on the environment that the ability of the planet's ecosystems to sustain future generations can no longer be taken for granted," the authors said.
The report cites widespread and growing problems such as the collapse of fisheries in some parts of the world because of over-exploitation, the creation of "dead zones" around the mouths of some rivers because of nitrogen runoff from farms, and environmental degradation in some dry-land ecosystems.
Within countries, said Harold Mooney, a professor of environmental biology at Stanford University, separate government agencies were often assigned to protect forests, regulate water pollution and oversee economic development -- even though changes in any one of those systems affected the others.
"When you enhance one service, like food production, you can detract from another," said Mooney, who co-chaired the panel that examined scientific data.
One way to address such problems, Mooney said, is to assign economic value to environmental benefits that many people take for granted. "We consider services free -- like clean water and pest regulation -- but they are not free," he said. "A number of services have a potential to get into the economic system that will help in making wise decisions."
Environmental advocates such as Nadia Martinez, a research fellow at the Institute for Policy Studies, a nonprofit think tank, applauded the report's findings but said she is concerned that governments could implement its market-based recommendations while ignoring its caveats. For example, she said, imposing a cost on clean water would disproportionately affect the poor.