A global map of the functionality of terrestrial ecosystems

The functionality of ecosystems is important for energy dissipation, ecosystem service provisioning, resilience to global change and adaptive capacity. Ecosystem complexity and ultimately functionality depend on higher levels of biodiversity, biomass, heterogeneity and evolutionary potential, such as genes. These characteristics are also likely to promote system resilience and adaptive capacity, which are becoming increasingly important under global climate change. This paper proposes a global proxy-based index of ecosystem functionality (EFI). The results generated for all the main global biomes recorded highest index values for tropical and extratropical forest ecoregions. Out of the selected variables vegetation density, topographical heterogeneity and carbon storage demonstrated strong correlations with the ecosystem functionality index. It is argued that the ecosystem functionality index is not only useful for ecological research and conservation science but also as an effective prioritization scheme for biodiversity conservation at the landscape scale in times of rapid global environmental change. Furthermore, ecosystems that express high ecosystem functionality are also believed to have greater buffer and adaptive capacity and it is proposed that these parameters help to identify those ecosystems that will contribute toward global sustainability. (C) 2012 Elsevier B.V. All rights reserved.