Campus Units

Agronomy

Document Type

Article

Publication Version

Published Version

Publication Date

2013

Journal or Book Title

Global Change Biology

Volume

19

Issue

1

First Page

327

Last Page

336

DOI

10.1111/gcb.12021

Abstract

Simultaneous measurement of N2O and CO2 flux at the soil surface with photoacoustic infrared spectroscopy (PAS) is gaining popularity due to portability, low maintenance, and ease-of-operation. However, the ability of PAS to measure N2O with accuracy and precision similar to gas chromatography (GC) is uncertain due to overlap in N2O, CO2, and H2O absorbance spectra combined with the large range in analyte concentrations. We tested the ability of six PAS units to simultaneously measure N2O and CO2 gas concentrations and fluxes with accuracy and precision similar to two GC units. We also evaluated H2O vapor and CO2 interferences with N2O measurement. The accuracy and precision of standard gas concentration measurements with PAS and GC were similar. High water vapor (~26 600 ppm) and CO2 concentrations (~4500 ppm) did not interfere with N2O measurement across the concentration range typically observed in static flux chambers at the soil surface (~0.5–3.0 ppm N2O). On average, N2O fluxes measured with the six PAS were 4.7% higher than one GC and 9.9% lower than the second GC.

Comments

This article is published as Iqbal J, Castellano MJ, Parkin TB. 2013. Evaluation of photoacoustic infrared spectroscopy for simultaneous measurement of N2O and CO2 gas concentrations and fluxes at the soil surface. Global Change Biology doi: 10.1111/gcb.12021. Posted with permission.

Rights

Works produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted.

Language

en

File Format

application/pdf

Included in

Agriculture Commons

Share

COinS