Root Distribution and Root Cohesion of Two Herbaceous Plants in the Loess Plateau of China
Round 1
Reviewer 1 Report
In general, the depth and importance of this study are insufficient, and the innovation has not been clearly explained. Only the root spatial distribution of the two herbaceous vegetation was investigated and their tensile strength was tested, which was not enough to support the conclusion that the root could significantly strengthen the soil. It is suggested that the root-soil strength test should be added to form a relatively complete study, and the introduction should be modified to illustrate the innovation and importance of the study.
1 Title
The full text emphasizes the Loess Plateau, and it is suggested to add the Loess Plateau qualifier in the title.
2 Abstract
line11-15: Research purposes and research methods should be punctuated.
3 Introduction
(1) line44-46: One of the most important factors affecting root cohesion is root mechanical strength. For the listed influencing factors, there should be a literature review.
(2) Line46-51: The correlation between this part of literature review and the importance of this study is not significant. The author has not carried out the research on the influence of root physical and chemical parameters on strength.
(3) Line48-50: Please explain the causal relationship of this sentence.
(4) Line61，This sentence has nothing to do with the following text.
(5) Line62-65: It is suggested that the background introduction of the Loess Plateau should be put in the same part.
(6) Line70-74: There is no research status on the root distribution of herbaceous plants. It is necessary to carry out this part of the literature review to explain the innovation and significance of this study.
4 Materials and Methods
(1) Line111: Please specify equation 4. The root has been completely separated from the soil, and the spatial distribution of root must change. How to calculate RAR and how to determine the shear area of soil mass?
(2) Line129: Why are the sample numbers different?
(3) Line135: Unit size selection basis? Basis for strain rate selection?
5 Results
(1) Line165-167: Please check the statement carefully. The statement is contradictory.
(2) Line183: The horizontal coordinates shall be indicated as the average diameter.
(3) line215: Explain how to conduct comparative analysis for different sample numbers.
(4) Line227: Please describe the specific calculation process of root cohesion in the research method. Is it calculated by the mean value?
(5) Line333:[28] please check.
(6) Line338-340: Please indicate references.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The authors should explain several issues:
1. What did your novelty compare to the previous research of lines 66-70?
2. I think the author should explain the sampling method of the herbaceous root system in more detail. The problem is how to sample roots in every layer, using ring samples or other methods for soil profile observation.
3. Did you observe a soil profile to identify lines 109-122?
4. Why did you use metallic materials' national standard tensile testing to measure the root tensile? I think it is not a suitable method. Is there any common method to measure root tensile strength?
5. I think the authors should add information regarding the characteristics of soil texture and hilly conditions illustrated by a contour map.
6. How did you get the finding results of lines 160-213?
7. I think the pictures of the root system in every layer observation and root tensile strength test were essential to explaining the method of a word used.
8. Figure 5b should be clarified using the cellulose and lignin content test you explained in lines 203-295. Is it equal finding results in root tree and root herbaceous?
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Row 188 - (Error! Reference source not found.) What is that ?
Row 285 - [23] and other trees such as Fagus longipeti olata Seem. – 23 and other ???
Row 333 - [28] found that the root system of Artemisia sacrorum. Here again ?
Row 334 - safety factor FS – what is safety factor, please explain , give citation .
Why did you choose only two pant species? For good statistical data, you can test more local plants to evaluate the ability of soil reinforcement by the plant roots.
Author Response
Comments and Suggestions for Authors
Great thanks to the reviewer for the comments on our draft. The revisions were addressed point by point in the following.
Row 188 - (Error! Reference source not found.) What is that ?
Response: Reference management tool had a hyperlink error. It should be ‘Table 1’.
Row 285 - [23] and other trees such as Fagus longipeti olata Seem. – 23 and other???
Response: Reference management tool had a hyperlink error. It should be ‘Hubble et al. [23]’.
Row 333 - [28] found that the root system of Artemisia sacrorum. Here again?
Response: Reference management tool had a hyperlink error. It should be ‘Su et al. [28]’.
Row 334 - safety factor FS – what is safety factor, please explain, give citation .
Response: Safety factor FS was introduced in the reference ‘Su et al. [28]’.
Why did you choose only two pant species? For good statistical data, you can test more local plants to evaluate the ability of soil reinforcement by the plant roots.
Response: The two species, Kochia scoparia (L.) Schrad and Artemisia sacrorum Ledeb are native and natural restored plants in Loess Plateau of China. Following the suggestion, we would investigate the physiological and mechanical properties of more local plants in future study.
Round 2
Reviewer 1 Report
The quality of the article has been improved by the author's revision. But the following questions remain:
1 Introduction
(1) Line66-67 and line31-38 have the same meaning. It is suggested that the mechanical reinforcement of roots should be one section and the spatial distribution of roots should be one section.
(2) Line67-70 is a literature review on the spatial distribution of roots. This part is not clear, there is no summary of previous relevant research conclusions, nor can it explain the current status of relevant research.
(3) Line71-72 points out the innovation of the article. The innovation of this study is only the plant species? I don't think the author has explained the innovation of the article clearly, and it is not enough to convince the readers to take the plant species as the innovation. In addition, to plant species as the innovation point, should also explain the importance of these two plants.
2 Materials and Methods
(1) Line108-109, stored at -4 ℃? references?
(2) Line163-164, references?
3 Conclusion&Abstract
(1) Results the statistical relationship between root distribution parameters and depth was uniform, which should be summarized in the conclusion and summary.
(2) Root cohesion is the same as 3 (1).
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 2 Report
I think the authors have improved their manuscript.
Author Response
Please see the attachment.
