Contribution of belowground biomass carbon to the stable soil organic matter pools: Bijdrage van C afkomstig van ondergrondse biomassa tot stabiele bodem organische stof

In summary, this PhD study investigated the relative contribution of below- versus above-ground biomass to the buildup and maintenance of stable SOC stock. We found that the relative stability of below- and above-ground biomass measured over a decadal period differs by a factor of 3.5. This implies that management oriented at storing SOC needs to be root-oriented and this knowledge could further help to improve the prediction of SOC dynamic by biogeochemical modeling. It also remains to be tested to what degree current biogeochemical models are capable of capturing these trends correctly. Furthermore, in this PhD it was also suggested - but not confirmed - that a delayed physical disturbance of root residues in the field and post-harvest remnant belowground biomass derived C could be the potential reasons for apparent relative stability of belowground biomass. Root biomass is mostly predicted based on aboveground yield by fixed R/S ratios, often leading to over- or underestimation under various soil conditions. Therefore, fast and reliable quantification of root biomass remains another big challenge to improve simulations of dynamics of SOC.