Implementing High Resolution Mass Spectroscopy and X-ray Computed Tomography to Decipher Soil Carbon Cycles: A Case Study Using the 1000 Soils Database

While there has been substantial progress understanding soil carbon storage over the past few decades, we still struggle to represent soil organic matter (SOM) decomposition in predictive models. In parallel, new technological advances allow unprecedented molecular resolution into soil processes. A challenge remains in obtaining standardized measurements of SOM composition paired with soil physiochemistry, hydrology, and respiration necessary for process-based model representations. To address this knowledge gap, we will be using soil cores collected from the 1000 Soils Project at the Environmental Molecular Sciences Laboratory (EMSL). This talk assesses continental-scale patterns in relationships between high resolution molecular data from soils, physiochemical, hydrological, and biological measurements. This talk will focuses on a limited set of soil cores collected in partnership with AmeriFluxs Year of Water sampling campaign and other collaborators, the first cores analyzed as part of an initial 3-year effort. Paired soil cores will be processed at EMSL with one core being split into the upper 10 cm and bottom 10 cm for biological (respiration and microbial biomass) and chemical (Liquid chromatography mass spectroscopy (LC-MS), electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS), and pH) assays, while physical properties (X-ray Computed Tomography (XCT), hydraulic properties, and texture) will be measured on the remaining intact core. In this talk, we present preliminary results from the initial pilot study, highlighting the relationship between SOM molecular composition and physicochemical, hydrological, and biological assays from natural and managed ecosystems across the US.