The Millennium Ecosystem Assessment: testing the limits of interdisciplinary and multi-scale science

The Millennium Ecosystem Assessment was modeled on the Intergovernmental Panel on Climate Change. It was carried out as a pilot of an assessment mechanism designed to meet decision makers' needs for information on how human actions were changing biodiversity and ecosystems, how those changes were affecting ecosystem services and human wellbeing, and what actions could be taken to enhance environmental conservation and human well-being. Despite the considerable research that was available in 2000 on biodiversity and ecosystems and on various aspects of human well-being, it was surprisingly difficult to find research at the interface of natural and social sciences and economics. Yet the key questions being posed by decision-makers (e.g., 'what will be the impact of biodiversity changes on local or national economies and human health') required that interdisciplinary research. We encountered other key research gaps, including the need for better understanding of the cross-scale impacts of both environmental changes and policy interventions and the challenges of addressing questions of human well-being across different cultures and different understandings of science and epistemology. This paper identifies some of the most challenging elements of the assessment and the steps that were taken to address them. In addition to the knowledge assessed by the MA, one of the important outcomes was to stimulate greater interdisciplinary and transdisciplinary research to address these issues that were not only fundamentally scientifically interesting, but also critically important for decision makers.