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Fiber Optic Sensor for Microscale Monitoring of Nitrate and Oxygen in the Rhizosphere


EMSL Project ID
60949

Abstract

We propose to develop a fiber sensor capable of continuous, in situ, spatially-resolved, simultaneous nitrate and dissolved oxygen measurements within the rhizosphere in tandem with oxygen optode mapping. Nitrogen is essential for plant growth; however, excess nitrate can lead to eutrophication in waterways and transformation of nitrate can result in greenhouse gas production (ammonia and N2O). Traditional nitrate measurements rely on ex situ characterization or sensors with spatial resolution insufficient (cm-scale) for adequately characterizing the spatiotemporal variability of nitrate in the rhizosphere. Oxygen optodes have been used for monitoring translocation of oxygen from the surface to the rhizosphere (Koop-Jakobsen et al., 2021). Completion of this work will result in a novel capability for simultaneous measurement of nitrate and oxygen concentrations at high spatial resolution (mm-scale) and oxygen optode mapping within the rhizosphere; this is vital for advancing research in the fields of greenhouse gas production, nitrogen cycling, and ecosystem health by enabling temporally resolved microscale monitoring of nitrate transport and fate. This work strongly supports the RF IRP and the “Rhizosphere Sensors” research area roadmap through development of a novel technique for monitoring nitrate and oxygen cycling in the subsurface; if successful, this work will attract several new EMSL users.

Project Details

Start Date
2023-08-01
End Date
N/A
Status
Active

Team

Principal Investigator

Joshua Torgeson
Institution
Pacific Northwest National Laboratory

Team Members

John Bargar
Institution
Environmental Molecular Sciences Laboratory

Matthew Kaufman
Institution
Worcester State University

Vivian Lin
Institution
Pacific Northwest National Laboratory