Transmission Characteristics of the Macropore Flow in Vegetated Slope Soils and Its Implication for Slope Stability

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The problem of landslides caused by precipitation is significant in world many areas. The development of methods, including numerical ones, for predicting the influence of soil quality on soil behavior is interesting. The researchers have done a good job of describing the current state of the research field. Particular attention was paid to modeling pores in the soil. The work is devoted to modeling the influence of macropores on soil infiltration. The use of computer tomography makes the work unique, which made it possible to obtain a model that is as close as possible to the real soil. The results presented in the work have a high degree of relevance.

 As recommendations, I would like to see the developer companies and countries where the equipment was manufactured and the software created: Somatom Sensation Open 40, HY-DRUS2D, COMSOL, MODFLOW, etc.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This manuscript conducted CT scanning on 3D macropore network of in-site soil column sample to establish macropore flow simulation, which provides guideline on macropore structure distribution and flow mechanism. Overall, it is well-written with conclusive analysis, to promote publication, some details need to be revised. Therefore, a minor revision is suggested.

 1. How to explain the keywords ‘well-vegetated slope’, the reviewer thinks the commonly used keyword is ‘vegetated slope’.

2. It is recommended to concise the description of study area in section 2.1 (Line 92).

3. In Table 1 (Line 246), there is a significant difference in terms of Ks of macropores in previous studies, i.e., 50-70 in reference [35], please explain it.

4. As the author mentioned, plant roots have great influence on macropore channels in soils for downward transmission of rainwater. However, there were no roots mentioned in the field sampling and analysis of this manuscription, please explain this.

5. It is recommended to add the newly published article in root-inspired geotechnics, for example, Zhang et al. (2024) https://doi.org/10.1016/j.gr.2023.12.018, since root growth can not only influence the soil structure, but also inspire designs of novel anchorage and foundation systems.

Comments on the Quality of English Language

English is acceptable 

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Review:

1. It is suggested to give the basic parameter table of modeling.

2. Why choose the lower part of the sample instead of the upper part? Does this affect the simulation results?

3. Does the yellow part of the model in Fig.7 represent pores? It is envisioned that annotations of various model components would be possible.

4. Does the one-day simulation period alter the outcomes because of its little duration? Is there a basis for the determination of the duration?

5. What is the principle of macropore calculation mentioned in section 3.1? Do you use the results of software calculations? It is suggested to specify the calculation principle.

6. An additional coordinate axis is suggested in Figure 9.

7. Figures 9 and 10 should provide an explanation for a-f.

8. The matrix flow rate and isolated macropores flow rate mentioned in the description of Fig.10 are not clear, and it is hoped that they can be clarified or annotated in the figure.

9. Please refer to the attachment for some modifications

To sum up, I think this paper still needs some minor modifications to be officially published.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Minor editing of English language required.

Author Response

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Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Dear authors,

thank you for submitting your interesting manuscript. I have just a few comments on the text.

1) The abstract exceeds the limit of 200 words, it can be shortened. 

2) In the chapter 2.1. (Study Area), by the elevation range from 1,820 to 2,940 m, there must also be a significant range in the annual precipitation L. 95-97). How was calculated the value of 1,082 mm? The same is probably true with the air temperature. Please, include also the climate district (according to any of the classification systems (Geiger-Koppen etc.).

3) In chapter 2.4 (MODFLOW simulation program), please provide the sentence "MODFLOW is a modular open-source computing program developed by the U.S. Geological Survey" an adequate literature source. 

3) Presentation of the results and the discussion sounds good to me. 

4) In chapter 6 (Conclusions), probably, the first sentence "In this paper, a realistic 3D numerical model of the macropore network was established using CT scanning of in-situ soil samples from Touzhai Valley. Afterwards the model was converted, and seepage numerical simulations of macropore flow were carried out based on MODFLOW" are not necessary. It was already mentioned in the Abstract and Introduction. Please go directly to the achievements of your study. 

Author Response

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Author Response File: Author Response.pdf