Data accessibility
Data supporting the results will be archived in a public repository such
as Dryad and a DOI will be included at the end of the article upon
acceptance.
Abstract (150 words):
Plant diversity and plant-consumer interactions likely interact to
influence ecosystem carbon fluxes but experimental evidence is scarce.
We examined how experimental removal of foliar fungi, soil fungi and
arthropods from experimental prairies planted with 1, 4 or 16 plant
species affected instantaneous rates of carbon uptake (GPP), ecosystem
respiration (Re) and net ecosystem exchange (NEE).
Increased plant diversity doubled plant biomass, in turn doubling GPP
and Re, but NEE remained unchanged. Removing foliar
fungi increased GPP and NEE, with greatest effects at low plant
diversity. After accounting for plant biomass, we found that removing
foliar fungi increased mass-specific flux rates by 48% by altering
plant species composition and community-wide foliar nitrogen content.
However, this elevated NEE effect disappeared when soil fungi and
arthropods were also removed, demonstrating ecosystem-scale impacts of
interactions among consumer groups. Thus, plant diversity and consumer
context determine the effects of plant-fungal interactions on ecosystem
carbon fluxes.