Nonstationarity of the electrical resistivity and soil moisture relationship in a heterogeneous soil system: a case study

Michot, Didier; Thomas, Zahra; Adam, Issifou

doi:https://doi.org/10.5194/soil-2-241-2016

Articles | Volume 2, issue 2

https://doi.org/10.5194/soil-2-241-2016

© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.

https://doi.org/10.5194/soil-2-241-2016

© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.

Articles | Volume 2, issue 2

Original research article

|

20 Jun 2016

Original research article |

| 20 Jun 2016

Nonstationarity of the electrical resistivity and soil moisture relationship in a heterogeneous soil system: a case study

Didier Michot, Zahra Thomas, and Issifou Adam

Download

Final revised paper (published on 20 Jun 2016)
Supplement to the final revised paper
Preprint (discussion started on 18 Sep 2015)
Supplement to the preprint

Interactive discussion

Status: closed

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

- Printer-friendly version

- Supplement

RC C538: 'Review', Anonymous Referee #1, 13 Oct 2015
- AC C593: 'Answer to reviewer #1', Didier Michot, 25 Nov 2015
RC C544: 'Review', Anonymous Referee #2, 19 Oct 2015
- AC C606: 'Answer to reviewer #2 comments', Didier Michot, 25 Nov 2015

Peer-review completion

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

ED: Revision (11 Dec 2015) by Nikolaus J. Kuhn

AR by Didier Michot on behalf of the Authors (19 Jan 2016) Author's response Manuscript

ED: Referee Nomination & Report Request started (20 Jan 2016) by Nikolaus J. Kuhn

RR by Anonymous Referee #2 (26 Jan 2016)

Suggestions for revision or reasons for rejection

While the manuscript is significantly improved, I find that especially some of the figures will still need edits to be acceptable for publication.

Fig 2b: Presenting cumulative rainfall for irregular periods (between measurements) is very illogical. The measurements you take are non-invasive (you don’t empty the soil-water by measuring ER) and this have no bearing on the relevant accumulation time. While it is hard to say what the relevant accumulation time is to summarize rainfall before a soil moisture measurement, it is certainly the same for each measurement (regular) and independent from the last ER measurement. (think about this, if you would measure for a second time in one day, there would surely be no precipitation accumulated since the last record, but does that have any relevance for the soil moisture). This needs to be changed.

Fig 4: While you apparently agree with my previous comment, the figure is unchanged. This image is hard to read and impossible to meaningfully interpret for any reader and this has no place in a manuscript in its current form.

Fig 8: The model curve needs to be presented as a curve! While I understand you are mostly interested in the points where you also have measured data, the model is independent from these data points and just plotting these points is misleading as it could imply a relation between both. This form of presentation is unacceptable.

4.3 \ Up4: ER for UP4 essentially remains constant over the whole measurement period, regardless soil wetness etc. The only logical conclusion here is that both are unrelated\independent. While you mention possible reasons for the lack of correlation,
4.3 is still packed with possible relations that are unwarranted (even if only because n=1). P16L27 – 31 … shifted to that of… … distinct differences..between wet and dry … … the relationship … had high variability … decease in matric potential… was related to a small change… etc.

4.3 \ 4.3 \ fig 10: It becomes clear now that while you advocate (or hypothesize) that many model relationships are needed for heterogeneous soils (fig 10), This is not the actual method used in the manuscript (One set of parameters). In that sense the study does provide no usable information on how many model parameter-sets \ relationships should be fitted or selected and if this multi-model approach has any advantage above a single parameter-set approach in a prediction setting. While this whole concept hardly becomes clear in the story the actual practice in this study and the proposed\presented method in figure 10 are inconsistent

Fig 10: The inserted references to figure 10 (sect 4.0) seem to have very little bearing on what is actually shown in the figure. Also this whole bit (see above) is rather inconsistent with the rest of the manuscript and has little bearing on the goals set out.

Goals (1. introduction)
While the goals set at the end of the introduction are much clarified, this is barely reflected in the discussion and conclusion section. I will take the liberty to conclude goal (ii) to verify the correlation between ER and soil moisture in a heterogeneous soil system:
ER and soil moisture have little correlation in close proximity to the hedgerow and the relation (if any) is non-stationary between wet and dry states, further reducing the value of ER for measuring soil moisture in the heterogeneous soils.
To me this seems like a perfectly valid conclusion, there should be no need to try and find a justification for your method while the results indicate otherwise. As it mostly renders the discussion hard to read while you circle around not wanting to say that this does not work very well.

Hide

ED: Reconsider after major revisions (19 Feb 2016) by Nikolaus J. Kuhn

AR by Didier Michot on behalf of the Authors (04 May 2016)

ED: Referee Nomination & Report Request started (11 May 2016) by Nikolaus J. Kuhn

ED: Revision (11 May 2016) by Nikolaus J. Kuhn

ED: Reconsider after major revisions (11 May 2016) by Nikolaus J. Kuhn

AR by Didier Michot on behalf of the Authors (12 May 2016) Author's response Manuscript

ED: Referee Nomination & Report Request started (18 May 2016) by Nikolaus J. Kuhn

RR by Wiebe Nijland (22 May 2016)

ED: Publish as is (27 May 2016) by Nikolaus J. Kuhn

ED: Publish as is (28 May 2016) by Eric C. Brevik (Executive editor)

AR by Didier Michot on behalf of the Authors (30 May 2016)

Short summary

This study focuses on temporal and spatial soil moisture changes along a toposequence crossed by a hedgerow, using ERT and occasional measurements. We found that the relationship between ER and soil moisture had two behaviors depending on soil heterogeneities. ER values were consistent with occasional measurements outside the root zone. The shift in this relationship was controlled by root system density and a particular topographical context in the proximity of the hedgerow.