Articles | Volume 10, issue 6
© Author(s) 2022. This work is distributed underthe Creative Commons Attribution 4.0 License.
Higher sediment redistribution rates related to burrowing animals than previously assumed as revealed by time-of-flight-based monitoring
- Final revised paper (published on 22 Dec 2022)
- Preprint (discussion started on 11 Jan 2022)
Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor |
: Report abuse
- RC1: 'Comment on esurf-2021-104', Anonymous Referee #1, 28 Jan 2022
- RC2: 'Comment on esurf-2021-104', Anonymous Referee #2, 29 Jan 2022
- AC1: 'Comment on esurf-2021-104', Paulina Grigusova, 20 Mar 2022
Peer review completion
AR: Author's response | RR: Referee report | ED: Editor decision
AR by Paulina Grigusova on behalf of the Authors (20 Mar 2022)  Author's response Author's tracked changes Manuscript
ED: Reconsider after major revisions (08 Apr 2022) by Lina Polvi Sjöberg
AR by Paulina Grigusova on behalf of the Authors (20 Apr 2022)  Author's response Author's tracked changes Manuscript
ED: Referee Nomination & Report Request started (22 Jun 2022) by Lina Polvi Sjöberg
RR by Anonymous Referee #1 (24 Jun 2022)
RR by Anonymous Referee #2 (31 Jul 2022)
ED: Publish subject to minor revisions (review by editor) (19 Aug 2022) by Lina Polvi Sjöberg
AR by Paulina Grigusova on behalf of the Authors (29 Aug 2022)  Author's response Author's tracked changes Manuscript
ED: Publish subject to minor revisions (review by editor) (26 Sep 2022) by Lina Polvi Sjöberg
AR by Paulina Grigusova on behalf of the Authors (06 Oct 2022)  Author's response Author's tracked changes Manuscript
ED: Publish subject to minor revisions (review by editor) (07 Oct 2022) by Lina Polvi Sjöberg
AR by Paulina Grigusova on behalf of the Authors (17 Oct 2022)  Author's response Author's tracked changes Manuscript
ED: Publish subject to minor revisions (review by editor) (19 Oct 2022) by Lina Polvi Sjöberg
AR by Paulina Grigusova on behalf of the Authors (19 Oct 2022)  Author's response Author's tracked changes Manuscript
ED: Publish as is (25 Nov 2022) by Lina Polvi Sjöberg
ED: Publish as is (26 Nov 2022) by Niels Hovius(Editor)
Time-of-flight monitoring reveals higher sediment redistribution rates related to burrowing animals than previously assumed
I like this study and I like the presentation of this novel method to measure soil redistribution. But…I am not sure I agree with all aspects of the application of this technique and the emphasis in terms of objectives in this study.
The authors had two study sites, with different climates, and presumably different species, and I think more could be made of this. How does sediment redistribution differ between the arid and the Mediterranean site, and what is the relative contribution of animal burrowing vs rainfall (which both presumably differ between the two sites) to this? This is an interesting question that the authors sort of get at, but not quite as explicitly, i.e. really teasing the two contributions apart within the two sites. To me that should almost be the main research question and focus. I.e. how effective are animals vs rainfall at moving sediment short distances (the authors are not following the sediment all the way down the slope after all)? I suggest splitting the paper, with one paper being a short methodological paper, with all the technical details of the method, and accuracy testing (I like how that was approached). And the other focusing on this comparison between arid and Mediterranean, using a clearly phrased research question, such as the one that I suggest. But, I would be careful in how to approach answering this question.
The authors tease apart these two contributions by looking at sediment redistribution within areas affected and not affected by burrowing animals and also during and after rainfall. When I read the section about the burrowed and non-burrowed sites the first time, I assumed some of the hillslopes were burrowed and some were not. But then I realized “affected” and “not affected” is at a much smaller scale, with the unaffected areas being in between and in close proximity to the burrows. How unaffected are the “unaffected” sites at this small scale then really? Surely the burrowing animals walk around in between their burrows, trampling the soil. Essentially, is the sediment redistribution in the non-affected areas representative of sites that do not have burrowing animals at all? If we took away the animals, would the situation in the non-affected sites be representative of how much sediment was redistributed? This has to be discussed a bit or acknowledged if there is doubt.
I also had concerns with upscaling, both spatially (to the size of the hillslope) and temporally (to a year). From a spatial perspective, I could not find anywhere how large a “scan” was, i.e. what are they upscaling from? Or how uniform the burrow sizes at any given point in time were? Burrows in the landscape are presumably at different stages of creation – most natural systems are dynamic systems with burrows being created and destroyed by rainfall continuously. What about other non-burrowed features in the landscape? Big rocks or trees etc. Are the scans and the non-burrowed areas within them really representative of the landscape? Can one just upscale from one burrow to a whole slope of burrows? I also don’t think it’s necessary to upscale to answer the interesting questions in this study (see paragraph 1 of my comments for what I think this is). That can be done at the smaller scale of individual burrows and non-burrowed areas (with some justification of why the non-burrowed areas are representative and giving careful thought regarding what to use as replication). In terms of the temporal upscaling (from seven months to a year), I am also not convinced. Burrowing animals do not continue burrowing at the same pace. And presumably the authors did not catch the burrowers right in the beginning, when the burrowing first started and was at its fastest. At the most the size of the mound gives an estimate of the minimum volume of soil contributed to the hillslope. How about seasonal effects? Some species dig burrows to nest, but are not fossorial, spending their time thereafter aboveground. I was also missing information on who these burrowers are. What sort of animals are we talking about? I assume it’s not the same species in the arid and the Mediterranean system? Or are there multiple species in both systems? This would influence how realistic upscaling is. Again, I also don’t think they need to upscale temporally to compare the two systems.
To summarise: I suggest two papers: one methods paper and one focusing on one main research question comparing the two systems (see my paragraph 1). Other interesting research questions that can potentially be answered with the data set are listed below.
Most of these questions are more ecological in nature (but can certainly be phrased in the context of biogeomorphology). I understand that this was not the intention of the article, and the focus is meant to be far more geomorphological, contributing to hillslope erosion modelling. But I am concerned that they cannot really contribute as much from an erosion modelling/geomorph perspective as they think, given my concerns with upscaling. I do see many interesting biogeo questions that can be answered though…
Some smaller issues