skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Versatile soil gas concentration and isotope monitoring: optimization and integration of novel soil gas probes with online trace gas detection

Journal Article · · Biogeosciences (Online)

Gas concentrations and isotopic signatures can unveil microbial metabolisms and their responses to environmental changes in soil. Currently, few methods measure in situ soil trace gases such as the products of nitrogen and carbon cycling or volatile organic compounds (VOCs) that constrain microbial biochemical processes like nitrification, methanogenesis, respiration, and microbial communication. Versatile trace gas sampling systems that integrate soil probes with sensitive trace gas analyzers could fill this gap with in situ soil gas measurements that resolve spatial (centimeters) and temporal (minutes) patterns. We developed a system that integrates new porous and hydrophobic sintered polytetrafluoroethylene (sPTFE) diffusive soil gas probes that non-disruptively collect soil gas samples with a transfer system to direct gas from multiple probes to one or more central gas analyzer(s) such as laser and mass spectrometers. Here, we demonstrate the feasibility and versatility of this automated multiprobe system for soil gas measurements of isotopic ratios of nitrous oxide (δ18O, δ15N, and the 15N site preference of N2O), methane, carbon dioxide (δ13C), and VOCs. First, we used an inert silica matrix to challenge probe measurements under controlled gas conditions. By changing and controlling system flow parameters, including the probe flow rate, we optimized recovery of representative soil gas samples while reducing sampling artifacts on subsurface concentrations. Second, we used this system to provide a real-time window into the impact of environmental manipulation of irrigation and soil redox conditions on in situ N2O and VOC concentrations. Moreover, to reveal the dynamics in the stable isotope ratios of N2O (i.e., 14N14N16O, 14N15N16O, 15N14N16O, and 14N14N18O), we developed a new high-precision laser spectrometer with a reduced sample volume demand. Our integrated system – a tunable infrared laser direct absorption spectrometry (TILDAS) in parallel with Vocus proton transfer reaction mass spectrometry (PTR-MS), in line with sPTFE soil gas probes – successfully quantified isotopic signatures for N2O, CO2, and VOCs in real time as responses to changes in the dry–wetting cycle and redox conditions. Broadening the collection of trace gases that can be monitored in the subsurface is critical for monitoring biogeochemical cycles, ecosystem health, and management practices at scales relevant to the soil system.

Research Organization:
Aerodyne Research, Inc., Billerica, MA (United States); Univ. of Arizona, Tucson, AZ (United States)
Sponsoring Organization:
USDOE Office of Science (SC); University of Arizona; Philecology Foundation; Landscape Evolutionary Observatory
Grant/Contract Number:
SC0018459
OSTI ID:
1839102
Alternate ID(s):
OSTI ID: 1981295
Journal Information:
Biogeosciences (Online), Journal Name: Biogeosciences (Online) Vol. 19 Journal Issue: 1; ISSN 1726-4189
Publisher:
Copernicus GmbHCopyright Statement
Country of Publication:
Germany
Language:
English

References (63)

Turbulence Effect on Gas Transport in Three Contrasting Forest Soils journal September 2012
Long-term and high-frequency non-destructive monitoring of water stable isotope profiles in an evaporating soil column journal January 2015
Biogenic volatile emissions from the soil: Biogenic volatile emissions from the soil journal May 2014
A fragrant neighborhood: volatile mediated bacterial interactions in soil journal November 2015
Mechanistic insights on the responses of plant and ecosystem gas exchange to global environmental change: Lessons from Biosphere 2 journal September 2014
The Volatilome: A Vital Piece of the Complete Soil Metabolome journal April 2021
The limits of signal averaging in atmospheric trace-gas monitoring by tunable diode-laser absorption spectroscopy (TDLAS) journal August 1993
Profile Nitrous Oxide and Carbon Dioxide Concentrations in a Soil Subject to Freezing journal January 1994
A new sampling technique to monitor concentrations of CH 4 , N 2 O and CO 2 in air at well-defined depths in soils with varied water potential journal June 2001
Measuring techniques for concentration and stable isotopologues of CO2 in a terrestrial ecosystem: A review journal December 2019
Distinguishing Nitrous Oxide Production from Nitrification and Denitrification on the Basis of Isotopomer Abundances journal January 2006
Reduced microbial diversity induces larger volatile organic compound emissions from soils journal April 2020
Monitoring water stable isotopic composition in soils using gas-permeable tubing and infrared laser absorption spectroscopy: Monitoring Water Stable Isotopic Composition in Soils journal June 2013
What are the instrumentation requirements for measuring the isotopic composition of net ecosystem exchange of CO 2 using eddy covariance methods?† journal June 2006
Porous tubing for use in monitoring soil CO2 concentrations journal September 2006
A multi-layer, closed-loop system for continuous measurement of soil CO 2 concentration journal August 2017
Development of a gas diffusion probe for the determination of methane concentrations and diffusion characteristics in flooded paddy soil journal September 1994
Continual in situ monitoring of pore water stable isotopes in the subsurface journal January 2014
Volatile organic compounds (VOCs) in soils journal February 2010
A global model of natural volatile organic compound emissions journal January 1995
The surface CO 2 gradient and pore-space storage flux in a high-porosity litter layer journal January 2004
From the Ground Up: Global Nitrous Oxide Sources are Constrained by Stable Isotope Values journal March 2015
High-resolution isotope measurements resolve rapid ecohydrological dynamics at the soil-plant interface journal February 2016
Constraining the atmospheric N2O budget from intramolecular site preference in N2O isotopomers journal May 2000
Terpenoids are Widespread in Actinomycetes: A Correlation of Secondary Metabolism and Genome Data journal December 2011
Soil microbiomes with distinct assemblies through vertical soil profiles drive the cycling of multiple nutrients in reforested ecosystems journal August 2018
Biogenic Volatile Organic Compounds in Arctic Soil: A Field Study of Concentrations and Variability With Vegetation Cover journal July 2020
A new method for continuously measuring the δ 13 C of soil CO 2 concentrations at different depths by laser spectrometry: Automatic measurement of soil CO 2 isotopic signature journal May 2013
Drought-induced nitrous oxide flux dynamics in an enclosed tropical forest journal August 2005
Continuous analysis of δ 18 O and δD values of water by diffusion sampling cavity ring-down spectrometry: a novel sampling device for unattended field monitoring of precipitation, ground and surface waters : Continuous analysis of δ journal November 2011
Measurement of dissolved H2 concentrations in methanogenic environments with a gas diffusion probe journal July 1993
Use of silicone tubing to sample nitrous oxide in the soil atmosphere journal June 1996
A method for in situ monitoring of the isotope composition of tree xylem water using laser spectroscopy journal June 2016
Measurements of methane emissions from natural gas gathering facilities and processing plants: measurement methods journal January 2015
Stable Carbon Isotope Fractionation by Methylotrophic Methanogenic Archaea journal August 2012
Methane, Carbon Dioxide and Nitrous Oxide Fluxes in Soil Profile under a Winter Wheat-Summer Maize Rotation in the North China Plain journal June 2014
Differential effects of redox conditions on the decomposition of litter and soil organic matter journal April 2021
An in situ method for real-time measurement of gas transport in soil: Monitoring of gas transport in soil journal March 2017
Design and performance of a dual-laser instrument for multiple isotopologues of carbon dioxide and water journal January 2015
Calling from distance: attraction of soil bacteria by plant root volatiles journal January 2018
Diffusion probe for gas sampling in undisturbed soil: Diffusion probe for soil gas sampling journal September 2014
Linking NO and N 2 O emission pulses with the mobilization of mineral and organic N upon rewetting dry soils journal December 2017
Profiling of soil volatile organic compounds after long-term application of inorganic, organic and organic-inorganic mixed fertilizers and their effect on plant growth journal December 2017
Life in Dry Soils: Effects of Drought on Soil Microbial Communities and Processes journal November 2018
Interlaboratory assessment of nitrous oxide isotopomer analysis by isotope ratio mass spectrometry and laser spectroscopy: current status and perspectives: Interlaboratory assessment of nitrous oxide isotopomer analysis journal August 2014
Isotopocule analysis of biologically produced nitrous oxide in various environments: ISOTOPOCULE ANALYSIS OF BIOLOGICAL N journal April 2015
First real-time isotopic characterisation of N2O from chemodenitrification journal December 2019
Membrane probe array: Technique development and observation of CO2 and CH4 diurnal oscillations in peat profile journal July 2007
The effect of soil drying on humus decomposition and nitrogen availability journal September 1958
Methane dynamics regulated by microbial community response to permafrost thaw journal October 2014
Performance properties and applications of polytetrafluoroethylene (PTFE)—a review journal February 2018
A New Method for In Situ Measurements of Oxygen Isotopologues of Soil Water and Carbon Dioxide with High Time Resolution journal January 2015
The HITRAN2012 molecular spectroscopic database journal November 2013
Quantification of methanogenic pathways using stable carbon isotopic signatures: a review and a proposal journal May 2005
Isotopic composition of tropospheric and soil N 2 O from successive depths of agricultural plots with contrasting crops and nitrogen amendments journal January 2007
Effects of Long-Term CO2 Enrichment on Soil-Atmosphere CH4 Fluxes and the Spatial Micro-Distribution of Methanotrophic Bacteria journal July 2015
Temporal changes in soil pore space CO2 concentration and storage under permanent grassland journal January 2007
Challenges to incorporating spatially and temporally explicit phenomena (hotspots and hot moments) in denitrification models journal January 2009
Diffusion of 15N-labelled N2O into soil columns: a promising method to examine the fate of N2O in subsoils journal June 2006
Evaluation of a New Reagent-Ion Source and Focusing Ion–Molecule Reactor for Use in Proton-Transfer-Reaction Mass Spectrometry journal September 2018
Sampling air from dung pats by silicone rubber diffusion chambers journal January 1990
A review of the molecular diffusivities of H2O, CO2, CH4, CO, O3, SO2, NH3, N2O, NO, and NO2 in air, O2 and N2 near STP journal March 1998
Equilibrium and Transport Properties of Gas Mixtures at Low Density: Eleven Polyatomic Gases and Five Noble Gases journal September 1990