This paper presents a conceptual framework that makes it possible to link the effects of environmental changes on vegetation to their effects on ecosystem functioning. As such, it describes an approach to scale up from individuals on to communities and ecosystems.

Enlarge image. “The “Holy Grail” framework calls for the development of a more quantitative assessment of key variables in functional ecology, and participates in the current renewal of community and ecosystem ecology. Current developments building on the “Holy Grail” involve the consideration of its applicability for other organisms (e.g. invertebrates, soil biota), and across trophic levels.”

The strength of our approach is therefore that it connects explicitly the physiology of organisms to the ecology of communities and the functioning of ecosystems. Beyond its fundamental interests for the understanding of the structure and dynamics of ecosystems, it offers a practical means and methodology with which to assess the impacts of environmental change on ecosystems.

The framework is of generic value, and should be applicable to all types of ecosystems and organisms, even though it was initially presented for (terrestrial) plants, for which there is the largest body of evidence and synthetic knowledge of functional traits thus far.

This research was originally developed in order to support projections of global change effects on ecosystem structure, functioning, and ecosystem services. Today, in addition to global change questions, there are many other potential applications, either in fundamental research in functional ecology, or in applied fields such as invasion or restoration ecology.

This paper proposes a strong conceptual framework that articulates earlier ideas on the usefulness of a functional approach. It is based on the synthesis of existing evidence supporting the role of functional traits, both for responses to environmental changes and for effects on ecosystem functioning. While previous papers had proposed the general idea, referred to as the "Holy Grail," this paper proposes for the first time a formal and detailed articulation based on mechanistic reasoning and hard evidence.

This paper presents an approach that makes it possible to assess the effects of differences in environmental conditions on community structure and ecosystem functioning. This is done by identifying the characteristics of plants, or other organisms that are both affected by these differences and, in turn, have an influence on ecosystem functioning such as biomass production, consumption by herbivores, or soil fertility.

For example, our framework has been applied to show how some easily measurable leaf characteristics can be used to know how changes in grassland management will affect fodder production and quality.

I became involved in this research by exposure to global change research and, more specifically, the endeavors of the Global Change and Terrestrial Ecosystems (IGBP) ¦Website¦ project in the early 1990s. I was fortunate to be exposed to these ideas through one of my postdoc supervisors, Prof. Ian Noble at the Australian National University. They made perfect sense in relation to my earlier work which showed that regeneration traits are useful to understand the dynamics of species diversity.

Because our approach connects explicitly the physiology of organisms to the ecology of communities and the functioning of ecosystems, its development has been greatly facilitated by the scientific context prevailing since the 1990s, which encourages interdisciplinary research.

This has been a very gratifying area of research with few problems of any significance. Most scientists are convinced these days about the value of generic patterns, or at least of searching them. We have also worked on methodologies to make this approach accessible, even with limited resources.

The "Holy Grail" framework calls for the development of a more quantitative assessment of key variables in functional ecology, and participates in the current renewal of community and ecosystem ecology. Current developments building on the "Holy Grail" involve the consideration of its applicability for other organisms (e.g. invertebrates, soil biota), and across trophic levels.

This research is leading to further conceptual developments for the assessment of ecosystem services. By combining the "Holy Grail" framework with quantitative approaches to the valuation of ecosystem services it will become possible to quantify the effects of environmental changes on services which are of value to different groups of people.