ABSTRACT
In the early 1990s, it became increasingly recognized that despite mounting global biodiversity losses (Ehrlich and Ehrlich 1981; Wilson 1988), science was limited in its ability to predict the effects of these changes. Now widely referred to as the “biodiversity crisis,” intensive research was triggered, seeking to answer the question: how important are diverse biotic communities for ecosystem functioning? (Schulze and Mooney 1993). The research underpinning this question represented a paradigm shift in ecology (Hillebrand and Matthiessen 2009). Traditionally, biodiversity research emphasized the regulation and maintenance of diversity, that is, the drivers of biodiversity, whereby biodiversity was seen as the consequence of the abiotic and biotic factors regulating a community (Chesson 2000). This emphasis has shifted toward understanding the consequences of biodiversity change on ecosystem functions, whereby biodiversity itself is a driver rather than a dependent variable in ecosystems (Schulze and Mooney 1993). Ecosystem processes sustain mankind: if biodiversity is needed for the processes, and in turn the services provided by nature to humans, then conserving biodiversity is a necessity for preserving the foundation on which our life depends (Cardinale et al. 2012; Millennium Ecosystem Assessment 2005).
