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The Pilot Analysis of Global Ecosystems

The Millennium Ecosystem Assessment
Pilot Analysis of Global Ecosystems | EarthTrends


The Pilot Analysis of Global Ecosystems (PAGE) was a one-year study of the state of the ecosystems humans are most dependent on for survival-agricultural, coastal, forest, freshwater, and grassland ecosystems. Using indicators and maps at global and continental scales, PAGE provides a "big picture" view of these ecosystems' current condition and future capacity to support human demands.

Together these five ecosystems cover most of the world's land surface and a significant (and economically important) portion of the oceans. And they account for the bulk of goods and services humans derive from ecosystems:

  • food and fiber production,
  • provision of pure and sufficient water,
  • maintenance of biodiversity,
  • storage of atmospheric carbon, and
  • provision of recreation and tourism opportunities.
The PAGE study took this unique "goods and services" approach to highlight the link between the condition of ecosystems and their potential to support human development. For each good and service, the PAGE study asked, Why is it important? and What shape is it in? In this way, PAGE — to the extent possible — addressed the question, How sustainable are our current patterns of ecosystem use? PAGE researchers synthesized information from a wide range of sources:

  • national, regional, and global data sets on food and fiber production;
  • sectoral assessments of agriculture, forestry, biodiversity, water, and fisheries;
  • national state-of-the-environment reports;
  • national and global assessments of ecosystem extent and change;
  • biological assessments of particular species or environments;
  • scientific research articles; and
  • various national and international data sets.
PAGE had a twofold objective: (1) provide "state of the art" information about the condition of ecosystems and (2) identify gaps in data and information. PAGE was designed to demonstrate at a global level the usefulness of an integrated assessment approach — one that concurrently assesses the range of goods and services an ecosystem produces rather than focusing on just one or two.

PAGE is not an integrated assessment. A truly integrated ecosystem assessment wouldn't focus on categories such as "forests" and "grasslands," as PAGE did; it would address spatially contiguous regions, such as a river basin. For example, the Amazon basin ecosystem includes agriculture, coastal areas, grasslands, forests, and freshwater. An integrated assessment of the Amazon would examine goods and services produced from this matrix of land uses and land cover (and trade-offs among them) rather than examine each in isolation.

The PAGE process, through its identification of key ecosystem indicators and data gaps, and in the breadth of its findings, has laid the substantive groundwork for the Millennium Ecosystem Assessment — an international effort to track ecosystem conditions and trends in a way that will allow governments and communities to better manage their use of ecosystems.

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