Sticky Roots -- Implications of Altered Rhizodeposition for the Fate of Mineral-associated Organic Matter in Natural Ecosystems
EMSL Project ID
51386
Abstract
The proposed research aims to improve mechanistic understanding of links among rhizodeposition of reactive organic compounds by plant roots, microbial activity, and the stability of mineral-associated organic matter in soils. Associations with minerals protect organic matter (OM) from microbial attack and thus preserve vast terrestrial soil carbon pools. However, compounds common in rhizodeposits can destabilize mineral-associated OM and cause soil carbon loss. Mineral-associated OM pools are considered relatively stable within the land model of DOE's newly developed Energy Exascale Earth System Model, disregarding this potential vulnerability of mineral-associated OM to the effects of rhizodeposition. Our overarching goal thus is to examine how the quality and dynamics of rhizodeposition affect the fate of otherwise stable mineral-associated OM. Our team has developed viral infection, which is widespread in terrestrial ecosystems, as a tool to manipulate rhizodeposition. Our work suggests that infection with common plant virus causes "sticky roots", enhancing the delivery of sugars and amino acids to the rhizosphere. Here we propose to combine a novel suite of in-situ monitoring approaches with EMSL's advanced mass spectrometry resources to determine how virus-induced changes in rhizodeposits in impact the stability of mineral-associated OM. Our results will improve mechanistic understanding of how root-microbe-mineral interactions control the fate of soil carbon. The explicit modeling of the dynamics of mineral-associated OM is now possible within process-level models, providing a ready conduit through which data generated here can contribute to understanding of ecosystem-scale carbon storage and nutrient cycling. And if viral infection leads quite generally to "sticky roots" that affect rhizosphere biogeochemistry, our perception of the potential importance of prevalent virus infection in terrestrial landscapes will be transformed.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2020-10-01
End Date
2021-12-31
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)
Team Members