Dark CO2 fixation in temperate forest soils

This study explores dark CO2 fixation using a well-characterized Eutric Cambisol soil plot in the Hainich National Park, Germany, which is the largest deciduous beech forest in Germany. With the aim to assess the role and mechanisms of dark CO2 fixation in temperate forest soils, we hypothesize that (I) dark autotrophic CO2 fixation in temperate forest soils increases down the soil profile and that (II) this process is enhanced by increase in soil CO2 concentrations. We propose that dark CO2 fixation contributes to microbial biomass and SOC along the entire soil profile and give a rough estimate for a potential global relevance of this process.