Billions of people, especially the rural poor, still lack access to nutritious food, clean water, sanitation, electricity or a healthy environment. Disenfranchised groups lack empowerment, opportunity and security: this is evidenced by the inequitable distribution of benefits from globalization; the limited access which many poor people have to productive resources and technological innovation; and the exclusionary land tenure arrangements found in many countries. Environmental degradation at the local (e.g. water pollution) and regional (e.g. land degradation) scales continues unabated in most developing countries – depleting natural capital, undermining the livelihoods of the poor, and limiting rural economic growth. And, at the global scale, the Earth’s climate continues to change, and biological diversity is being lost at an unprecedented rate, undermining the ecological basis for sustainable development.

Progress towards sustainable development depends upon better managing the Earth’s ecosystems. These affect human well-being directly through supplying such goods as food, timber, genetic resources and medicines, and such services as water purification, flood control, coastline stabilization, carbon sequestration, waste treatment, biodiversity conservation, soil generation, pollination, maintenance of air quality, and the provision of aesthetic and cultural benefits. And they affect it indirectly through impacts on poverty, health, livelihoods, security and economic development.

Human impact
The magnitude of human-induced changes in terrestrial and marine ecosystems is unprecedented. Some 40 to 50 per cent of land is now transformed or degraded. Some 60 per cent of the world’s major fisheries are overfished. Natural forests continue to disappear at a rate of about 14 million hectares each year. And other ecosystems such as wetlands, mangroves and coral reefs have been substantially reduced or degraded. Other human-induced impacts on ecosystems include alteration of the nitrogen and carbon cycles causing acid rain, eutrophication, climate change and increased rates of species extinction. All these changes have had significant, but largely unquantified, impacts on the production of ecosystem goods and services.

Projected demographic changes and economic growth will lead to an increasing demand for biological resources. This implies even greater impacts on ecosystems and the goods and services that flow from them. Projections suggest, for example, that an additional one third of global land cover will be transformed over the next 100 years; world demand for cereals will double within the next 25-50 years; demand for freshwater will increase to an equivalent of more than 70 per cent of run-off: and demand for wood will double over the next half-century.

The magnitude of human-induced changes in terrestrial and marine ecosystems is unprecedented

It is now well recognized that there is a trade-off among ecological goods and services. While converting a forest to agriculture may increase food production, for example, it may decrease the supply of clean water, timber, biodiversity or flood control – which may be of equal or greater importance. An integrated approach to agriculture, land use, and coastal and ocean management must be adopted to encompass the differing ecological, economic, social, cultural and institutional implications of sustainable use and conservation.

As the capability of many ecosystems to provide essential goods and services is being diminished, many governments are now beginning to recognize the need for managing these basic life support systems more effectively: this is particularly important as a tool for poverty alleviation. The importance of managing ecosystems better is also recognized in the private sector, both by industries dependent directly on biological resources (such as timber, fishing or agricultural firms), and those that are not (e.g. extractive industries such as mining). Companies increasingly recognize the importance of being good ‘corporate citizens’ by focusing on the triple bottom line of economic growth that is environmentally and socially sustainable.

Multi-scale assessment
The United Nations Secretary-General recognized the growing burden that degraded ecosystems are placing on human well-being and economic development in his Millennium Report to the United Nations General Assembly, and said:

‘It is impossible to devise effective environmental policy unless it is based on sound scientific information. While major advances in data collection have been made in many areas, large gaps in our knowledge remain. In particular, there has never been a comprehensive global assessment of the world’s major ecosystems. The planned Millennium Ecosystem Assessment, a major international collaborative effort to map the health of our planet, is a response to this need.’

The Millennium Ecosystem Assessment (MA) is a multi-scale assessment: this means that it comprises interlinked assessments conducted at different geographic scales, ranging from local communities to the entire globe. It has been authorized by the Convention on Biological Diversity, the Convention to Combat Desertification and the Ramsar Wetlands Convention, and is carefully coordinated with other international scientific assessments. It will also contribute directly to decision-making needs at sub-national scales and within the private sector and civil society.

The Assessment builds upon earlier sectoral and integrated assessments and focuses on three issues: the current and historical trends in ecosystems and their contribution to human well-being; options for conserving ecosystems and increasing their contribution to human welfare; and future scenarios for change in ecosystems and human well-being. Its ‘value added’ is in its cross-sectoral and cross-scale analysis.

Three issues
The multi-scale framework is unique. Other global assessments have included strong regional analyses (e.g. the third assessment report of the Intergovernmental Panel on Climate Change), but the MA also incorporates formal assessments undertaken at the sub-global scale, with their own stakeholders, authorizing environment and user-driven process.

The MA has been structured to ensure that it meets the tests of saliency, credibility, transparency, legitimacy and utility. It has been designed to:

• meet high scientific and technical standards, including a rigorous and transparent peer review process;

• be policy relevant but not policy prescriptive;

• be independent from political pressure, while responsive to user needs;

• include an open process for nominating and selecting experts ensuring regional, disciplinary, gender and stakeholder balance, while seeking to expand the community of experts conducting the assessment to include local and traditional knowledge;

• ensure a balanced reporting of perspectives, identifying what is known and unknown, including key uncertainties;

• embrace issues associated with risk assessment, management and communication;

• be owned and authorized by all relevant stakeholders;

• include an effective strategy of outreach and communication of the process and results.

Major sponsors include the Global Environment Facility, the United Nations Foundation, the David and Lucille Packard Foundation, the World Bank, UNEP, and the Governments of Norway, China, Japan and the United States.