Root and leaf litter diversity belowground shape soil carbon stabilization and priming through altered decomposition dynamics

Root and leaf turnover is a major contributor to soil organic carbon (SOC) dynamics and storage. However, while roots of multiple species occur in soils, and leaves are often incorporated to soil by bioturbation processes, it remains unknown how litter mixing in soils influences litter decomposition processes, and the associated carbon (C) fluxes controlling the SOC balance. To address this issue, we studied the (almost complete) decomposition of 13C labeled single leaf and root litters and 15 realistic litter mixtures incorporated into soil in the laboratory. We studied litter mass loss and litter nitrogen concentration as litters decomposed, tracked litter 13C into the mineral-associated organic matter (MAOM) and particulate organic matter (POM) fractions of the SOC, and quantified litter influence on native SOC mineralization (i.e., priming). Litter diversity increased litter decomposition rates, yet not due to nitrogen transfer and immobilization in decomposing litters. Litter tanni..., , # Root and leaf litter diversity belowground shape soil carbon stabilization and priming through altered decomposition dynamics https://doi.org/10.5061/dryad.gqnk98t35 The dataset contains a description of the 15 plant mixtures used and contains information about the litter decomposition C and nitrogen (N) dynamics, as well as measures indicating the litter-derived C in the MAOM and POM fraction, the priming in both these fractions, as well as their overall net balance. Data of the corresponding single species decomposition as well as the litter chemical traits, described in Huys et al. (2022) J. Ecology, can be found in: Dryad Digital Repository, [https://doi.org/10.5061/dryad.m63xsj45g](https://doi.org/10.5061/dryad.m63xsj45g) ### FE-2025-01250.xlsx The 1st column (A) indicates the number of litters contained in each of the 15 (rows) litter mixtures. The 2nd to 7th column indicates which plant species was present in each mixture, where D. glo = Dactylis glomerata; P. Hie = Picris..., ,