Data from: The importance of species identity and interactions on multifunctionality depends on how ecosystem functions are valued

Studies investigating how biodiversity affects ecosystem functioning
increasingly focus on multiple functions measured simultaneously
(‘multifunctionality’). However, few such studies assess the role of
species interactions, particularly under alternative environmental
scenarios, despite interactions being key to ecosystem functioning. Here
we address five questions of central importance to ecosystem
multifunctionality using a terrestrial animal system: 1) Does the
contribution of individual species differ for different ecosystem
functions?; 2) Do inter-species interactions affect the delivery of single
functions and multiple functions?; 3) Does the community composition which
maximises individual functions also maximise multifunctionality?; 4) Is
the functional role of individual species, and the effect of interspecific
interactions, modified by changing environmental conditions?; and 5) How
do these roles and interactions change under varying scenarios where
ecosystem services are weighted to reflect different societal preferences?
We manipulated species’ relative abundance in dung beetle communities and
measured 16 functions contributing to dung decomposition, plant
productivity, nutrient recycling, reduction of greenhouse gases, and
microbial activity. Using the Multivariate Diversity-Interactions
framework, we assessed how changes in species identity, composition, and
interspecific interactions affected these functions in combination with an
environmental driver (increased precipitation). This allowed us to
identify key species and interactions across multiple functions. We then
developed a Desirability Function Approach to examine how individual
species and species mixtures contribute to a desired state of overall
ecosystem functioning. Species contributed unequally to individual
functions, and to multifunctionality, and individual functions were
maximised by different community compositions. Moreover, the species and
interactions important for maintaining overall multifunctionality depended
on the weight given to individual functions. This combination of
methodological approaches allows us to resolve the interactions and
indirect effects among species that drive ecosystem functioning, revealing
how multiple aspects of biodiversity can simultaneously drive ecosystem
functioning. Optimal multifunctionality is therefore context-dependent,
and is sensitive to the valuation of services. Our results highlight the
importance of a multifunctionality perspective for complete assessment of
species’ functional contributions.