Relationship between plant community, N concentration, and carbon
fluxes
Removal of foliar fungi or soil fungi reduced the relative abundance of
C4 grasses and increased leguminous forbs (Table S8, Fig. S2). Mass
specific fluxes (GPP and Re) declined with increasing
abundance of C4 plants and increasing belowground biomass (Table S9,
Fig. 4), and increased with community-wide foliar N content (Table S10,
Fig. 5) as would be expected from a shift towards a more resource
conservative plant strategy. These trends were interrelated: community
foliar N content increased as the relative abundance of leguminous forbs
increased, and decreased with an increase in C4 grasses and in
belowground biomass (p<0.001, Table S11, Fig. 6). Removal of
heterotrophs weakened the relationship between mass-specific fluxes and
foliar N content (Table S10) and between foliar N content and
belowground biomass (Table S11).