Iron Oxide-Organic Carbon Interactions during Redox Cycles
EMSL Project ID
49526
Abstract
The proposed project will investigate dynamics in the chemical composition of organic carbon (OC) and its association with iron (Fe) oxide during redox reactions. Iron oxide mineral phase transformation under redox cycles will alter aqueous/solid-phase OC speciation and metabolism of Fe-bound OC. Our overarching hypothesis is that the dynamics in OC molecular compositions are governed by the Fe-OC associations (sorptive or incorporative), which are consequently regulated by the mineral phase of Fe oxides. We will monitor OC and Fe dynamics during anaerobic-aerobic redox cycles in target samples from representative forest soils and synthesized Fe oxide-OC complexes using model Fe oxides, i.e. ferrihydrite (Fh), and regular/ nano-sized goethite. These samples will be incubated with Fe(III)-reducing bacteria under anaerobic conditions, followed by oxidation of aqueous/solid-phase Fe(II) compounds driven by the input of oxygen. The release and degradation of OC will be measured during the redox cycles. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) will be utilized to characterize the chemical structure of released OC under the transition conditions. This project will document novel information about how the Fe-bound OC would be transformed during redox reaction.
Project Details
Project type
Limited Scope
Start Date
2016-11-07
End Date
2017-01-07
Status
Closed
Released Data Link
Team
Principal Investigator