Earth’s environment is ongoing massive changes with strong impacts on ecosystem functioning and therefore on the ecosystem services for human societies. It is thus a key priority to improve understanding of ecosystem functioning as well as the capacity for predicting its dynamics under environmental change. 

Traditionally, ecosystem functioning is understood to be the outcome of contemporary environmental drivers and their interplay with dominant species. However, during the last two decades there has been increasing emphasis on – and controversy over - the additional importance of species diversity for ecosystem functioning.