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

Gil-Loaiza, Juliana; Roscioli, Joseph R.; Shorter, Joanne H.; Volkmann, Till H. M.; Ng, Wei-Ren; Krechmer, Jordan E.; Meredith, Laura K.

doi:https://doi.org/10.5194/bg-19-165-2022

Articles | Volume 19, issue 1

https://doi.org/10.5194/bg-19-165-2022

© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/bg-19-165-2022

© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 19, issue 1

Research article

|

10 Jan 2022

Research article |

| 10 Jan 2022

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

Juliana Gil-Loaiza, Joseph R. Roscioli, Joanne H. Shorter, Till H. M. Volkmann, Wei-Ren Ng, Jordan E. Krechmer, and Laura K. Meredith

Download

Final revised paper (published on 10 Jan 2022)
Supplement to the final revised paper
Preprint (discussion started on 28 Dec 2020)
Supplement to the preprint

Interactive discussion

Status: closed

AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment

- Printer-friendly version

- Supplement

RC1: 'Comments', Anonymous Referee #1, 13 Feb 2021
- AC3: 'Reply on RC1', Juliana Gil Loaiza, 02 Apr 2021
RC2: 'reviewer 2 comments.', Anonymous Referee #2, 13 Feb 2021
- AC1: 'Reply on RC2', Juliana Gil Loaiza, 01 Apr 2021
RC3: 'Comments to: "Versatile soil gas concentration and isotope monitoring: optimization and integration of novel soil gas probes with online trace gas detection"', Anonymous Referee #3, 18 Mar 2021
- AC2: 'Reply on RC3', Juliana Gil Loaiza, 01 Apr 2021

Peer-review completion

AR: Author's response | RR: Referee report | ED: Editor decision

ED: Publish subject to minor revisions (review by editor) (23 Apr 2021) by Nicolas Brüggemann

ED: Reconsider after major revisions (27 Apr 2021) by Nicolas Brüggemann

AR by Juliana Gil Loaiza on behalf of the Authors (16 Jun 2021) Author's response Manuscript

ED: Referee Nomination & Report Request started (26 Sep 2021) by Nicolas Brüggemann

RR by Albrecht Neftel (29 Sep 2021)

Suggestions for revision or reasons for rejection

I read with interest this paper and was impressed by the analytical development presented to characterize trace gas composition in the open pore space of a soil matrix. The revised version clarified the most important concerns raised by the reviewers.

It is a pleasure to see a follow up of the membrane tube technique (METT) that we have developed many years ago. The presented instrumental setup offers the potential to explore the large variability of microbial and chemical processes in soil that controls trace gas exchange within the soil ad between the atmosphere and the soil. It is a milestone to get simultaneously access to continuous data on isotopic ratios of nitrous oxide (δ18O, δ15N, and the δ15N site-preference of N2O), methane, carbon dioxide (δ13C), and VOCs in small gas samples. The paper first presents data from a control experiment from an artificial inert soil imitation to characterize collection efficiency and reproducibility as the gas probing relies on passive diffusion through the porous membrane tube. Obviously, the gas flow will have a key influence on the measured concentrations. Secondly data from packed soil core with an embedded sampling tube are presented. An N2O pulse as consequence of an irrigation was traced. The information on the isotopic signature of the N2O concentration in the soil allows to disentangle different production pathways for N2O. This is a valuable information as in most cases the interpretation of the mechanisms leading to an observed N2O flux is a lot of guessing.
Secondly changes in soil VOC production in response to redox shift are presented.

When we developed the METT system and analyzed the data, we have been aware, that in the best case we got representative trace gas concentrations in an additional large pore artificially introduced in the soil. These concentrations might not be representative for the most important processes that e.g. control the N2O production and consumption as the oxygen concentration is likely higher as in small pores. Our goal was to keep disturbances to the soil gas distribution as small as possible with an attempt to recycle the gas. It would be important to test whether the “old” METT approach yields systematically different results.
I have only a small criticism. The idea of articles in BG is on aspects of the interactions between the biological, chemical, and physical processes in terrestrial life with the geosphere, hydrosphere, and atmosphere. The paper has a very technical focus and presents a toolbox what can be measured. The paper would gain in strength if a proposition what relevant new question linking the different spheres would be given.

Hide

RR by Anonymous Referee #1 (20 Oct 2021)

ED: Publish subject to technical corrections (04 Nov 2021) by Nicolas Brüggemann

AR by Juliana Gil Loaiza on behalf of the Authors (10 Nov 2021) Author's response Manuscript

Download

Article (4383 KB)
Full-text XML

Short summary

We evaluated a new diffusive soil probe integrated with high-resolution gas analyzers to measure soil gases in real time at a centimeter scale. Using columns with simple silica and soil, we captured changes in carbon dioxide (CO₂), volatile organic compounds (VOCs), and nitrous oxide (N₂O) with its isotopes to distinguish potential nutrient sources and microbial metabolism. This approach will advance the use of soil gases as important signals to understand and monitor soil fertility and health.