Roots Selectively Decompose Litter to Mine Nitrogen and Build New Soil Carbon

Themes: Sustainability

Keywords: Biomass Analytics, Field Data


Ridgeway, J., Kane, J., Morrissey, E., Starcher, H., Brzostek, E. Oct. 28, 2023. Data from: “Roots Selectively Decompose Litter to Acquire Nitrogen and Build New Soil Carbon.” Zenodo Repository. DOI: 10.5281/zenodo.8408435.


The total mass of litter C (left) and litter N (right) recovered in the light POM fraction (light green), heavy POM fraction (dark blue), and MAOM fraction (brown) for root and fungal ingrowth (root), root exclusion and fungal ingrowth (fungal), or root and fungal exclusion (none) soil cores. Litter mass is calculated from measurements of δ 13C and δ 15N isotopic values, and mean data is shown with standard error bars. Letters denote statistically significant differences between the ingrowth core treatments in total C or N recovered in all SOM pools (p < 0.05).

Plant-microbe interactions in the rhizosphere shape carbon and nitrogen cycling in soil organic matter (SOM). However, there is conflicting evidence on whether these interactions lead to a net loss or increase of SOM. In part, this conflict is driven by uncertainty in how living roots and microbes alter SOM formation or loss in the field. To address these uncertainties, we traced the fate of isotopically labelled litter into SOM using root and fungal ingrowth cores incubated in a Miscanthus x giganteus field. Roots stimulated litter decomposition, but balanced this loss by transferring carbon into aggregate associated SOM. Further, roots selectively mobilized nitrogen from litter without additional carbon release. Overall, our findings suggest that roots mine litter nitrogen and protect soil carbon.


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