Session

Belowground production of CO2 has been suggested to be highly responsive to climate change, but there are large uncertainties as to the role of soil organisms involved in the mineralization of soil organic matter and subsequent CO2 release. Combining field observations across montane and subalpine grasslands in the Central Alps with manipulative incubation experiments, we investigated the role of microbial and invertebrate community compositions and activities in shaping soil respiration under different environmental conditions and weather extremes. We measured soil CO2 release jointly with the soil functional profile based on targeted microorganisms’ intracellular DNA fractions, which contained information about the active organisms in soil and we classically determined the prevailing soil fauna and biomass. First results indicate distinct effects of soil invertebrates on microbial communities with cascading consequences for soil CO2 emissions, which were particularly pronounced under weather extremes.