This User proposal will facilitate the completion of data analysis central to the broader research effort investigating soil organic matter (SOM) stabilization and vulnerability using a multi-scale approach and spanning a broad range of ecological domains, soil types, and land uses in the United States. This is part of a broader effort of work to build a continental-scale fluorescence model of soils extracts coupled with molecular characterization by Fourier transform ion cyclotron resonance mass spectroscopy (FTICR-MS). We have worked on an EMSL Accelerated Science Project led by Nancy Hess to develop and refine our sequential cold-water hot-water extraction protocol, sample preparation, and analysis. In addition we have worked with Nancy Hess on an EMSL Rapid Proposal to complete the analysis for sequential water methanol and chloroform extraction, that will help provide a mechanistic understanding of how soil organic matter is stabilized across a diverse range of soils. This EMSL User proposal is targeted at completing the FTICR-MS data analysis of soil extracts from a broad range of soils. Specifically, we aim to use FTICR-MS along with an intensive characterization of soil characteristics relevant to SOM stabilization and vulnerability to gain new insight into the molecular composition of DOM in soil solutions to further our understanding of DOM composition at the molecular scale across the range of ecosystems and soil orders present in North America. Additionally, we will use FTICR-MS to elucidate the molecular structure of components isolated in fluorescence spectroscopy parallel factor analysis (PARAFAC) components and lend new interpretive power to fluorescence spectroscopy as a tracer for the migration of specific DOM components from soils to aquatic systems.
The National Science Foundation, Division of Environmental Biology Program (Award Nos. EF-1340681, EF-1340504, EF-1340516, EF-1340250, and DBI-1724433).|The National Science Foundation award for the National Ecological Observatory Network (NSF#1724433).