PONE-D-20-35754

Comparison of soil organic carbon and total nitrogen stocks between farmland treated with level soil bund of different age and adjacent farmland without conservation measure: in the case of southwestern Ethiopia

PLOS ONE

Dear Dr. Hailu,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Feb 18 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Sergio Saia, Ph.D.

Academic Editor

PLOS ONE

Journal Requirements:

When submitting your revision, we need you to address these additional requirements.

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and

https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

2.Thank you for stating the following financial disclosure:

 "No"

At this time, please address the following queries:

1. Please clarify the sources of funding (financial or material support) for your study. List the grants or organizations that supported your study, including funding received from your institution.
2. State what role the funders took in the study. If the funders had no role in your study, please state: “The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.”
3. If any authors received a salary from any of your funders, please state which authors and which funders.
4. If you did not receive any funding for this study, please state: “The authors received no specific funding for this work.”

Please include your amended statements within your cover letter; we will change the online submission form on your behalf.

3.Thank you for stating the following in your Competing Interests section: 

"No"

Please complete your Competing Interests on the online submission form to state any Competing Interests. If you have no competing interests, please state "The authors have declared that no competing interests exist.", as detailed online in our guide for authors at http://journals.plos.org/plosone/s/submit-now

 This information should be included in your cover letter; we will change the online submission form on your behalf.

Please know it is PLOS ONE policy for corresponding authors to declare, on behalf of all authors, all potential competing interests for the purposes of transparency. PLOS defines a competing interest as anything that interferes with, or could reasonably be perceived as interfering with, the full and objective presentation, peer review, editorial decision-making, or publication of research or non-research articles submitted to one of the journals. Competing interests can be financial or non-financial, professional, or personal. Competing interests can arise in relationship to an organization or another person. Please follow this link to our website for more details on competing interests: http://journals.plos.org/plosone/s/competing-interests

4.In your Data Availability statement, you have not specified where the minimal data set underlying the results described in your manuscript can be found. PLOS defines a study's minimal data set as the underlying data used to reach the conclusions drawn in the manuscript and any additional data required to replicate the reported study findings in their entirety. All PLOS journals require that the minimal data set be made fully available. For more information about our data policy, please see http://journals.plos.org/plosone/s/data-availability.

Upon re-submitting your revised manuscript, please upload your study’s minimal underlying data set as either Supporting Information files or to a stable, public repository and include the relevant URLs, DOIs, or accession numbers within your revised cover letter. For a list of acceptable repositories, please see http://journals.plos.org/plosone/s/data-availability#loc-recommended-repositories. Any potentially identifying patient information must be fully anonymized.

Important: If there are ethical or legal restrictions to sharing your data publicly, please explain these restrictions in detail. Please see our guidelines for more information on what we consider unacceptable restrictions to publicly sharing data: http://journals.plos.org/plosone/s/data-availability#loc-unacceptable-data-access-restrictions. Note that it is not acceptable for the authors to be the sole named individuals responsible for ensuring data access.

We will update your Data Availability statement to reflect the information you provide in your cover letter.

5. PLOS requires an ORCID iD for the corresponding author in Editorial Manager on papers submitted after December 6th, 2016. Please ensure that you have an ORCID iD and that it is validated in Editorial Manager. To do this, go to ‘Update my Information’ (in the upper left-hand corner of the main menu), and click on the Fetch/Validate link next to the ORCID field. This will take you to the ORCID site and allow you to create a new iD or authenticate a pre-existing iD in Editorial Manager. Please see the following video for instructions on linking an ORCID iD to your Editorial Manager account: https://www.youtube.com/watch?v=_xcclfuvtxQ

6. Please amend either the abstract on the online submission form (via Edit Submission) or the abstract in the manuscript so that they are identical.

7. We note that [Figure(s) 1] in your submission contain map images which may be copyrighted. All PLOS content is published under the Creative Commons Attribution License (CC BY 4.0), which means that the manuscript, images, and Supporting Information files will be freely available online, and any third party is permitted to access, download, copy, distribute, and use these materials in any way, even commercially, with proper attribution. For these reasons, we cannot publish previously copyrighted maps or satellite images created using proprietary data, such as Google software (Google Maps, Street View, and Earth). For more information, see our copyright guidelines: http://journals.plos.org/plosone/s/licenses-and-copyright.

We require you to either (1) present written permission from the copyright holder to publish these figures specifically under the CC BY 4.0 license, or (2) remove the figures from your submission:

1.    You may seek permission from the original copyright holder of Figure(s) [1] to publish the content specifically under the CC BY 4.0 license. 

We recommend that you contact the original copyright holder with the Content Permission Form (http://journals.plos.org/plosone/s/file?id=7c09/content-permission-form.pdf) and the following text:

“I request permission for the open-access journal PLOS ONE to publish XXX under the Creative Commons Attribution License (CCAL) CC BY 4.0 (http://creativecommons.org/licenses/by/4.0/). Please be aware that this license allows unrestricted use and distribution, even commercially, by third parties. Please reply and provide explicit written permission to publish XXX under a CC BY license and complete the attached form.”

Please upload the completed Content Permission Form or other proof of granted permissions as an "Other" file with your submission.

In the figure caption of the copyrighted figure, please include the following text: “Reprinted from [ref] under a CC BY license, with permission from [name of publisher], original copyright [original copyright year].”

2.    If you are unable to obtain permission from the original copyright holder to publish these figures under the CC BY 4.0 license or if the copyright holder’s requirements are incompatible with the CC BY 4.0 license, please either i) remove the figure or ii) supply a replacement figure that complies with the CC BY 4.0 license. Please check copyright information on all replacement figures and update the figure caption with source information. If applicable, please specify in the figure caption text when a figure is similar but not identical to the original image and is therefore for illustrative purposes only.

The following resources for replacing copyrighted map figures may be helpful:

USGS National Map Viewer (public domain): http://viewer.nationalmap.gov/viewer/

The Gateway to Astronaut Photography of Earth (public domain): http://eol.jsc.nasa.gov/sseop/clickmap/

Maps at the CIA (public domain): https://www.cia.gov/library/publications/the-world-factbook/index.html and https://www.cia.gov/library/publications/cia-maps-publications/index.html

NASA Earth Observatory (public domain): http://earthobservatory.nasa.gov/

Landsat: http://landsat.visibleearth.nasa.gov/

USGS EROS (Earth Resources Observatory and Science (EROS) Center) (public domain): http://eros.usgs.gov/#

Natural Earth (public domain): http://www.naturalearthdata.com/

8. Please include captions for your Supporting Information files at the end of your manuscript, and update any in-text citations to match accordingly. Please see our Supporting Information guidelines for more information: http://journals.plos.org/plosone/s/supporting-information.

9.We noticed you have some minor occurrence of overlapping text with the following previous publication(s), which needs to be addressed:

http://article.sciencepublishinggroup.com/html/10.11648.j.ijnrem.20160102.15.html

https://file.scirp.org/Html/6776.html

https://www.gssrr.org/index.php/JournalOfBasicAndApplied/article/view/6167

In your revision ensure you cite all your sources (including your own works), and quote or rephrase any duplicated text outside the methods section. Further consideration is dependent on these concerns being addressed.

Additional Editor Comments:

Specifically, it seems that your manuscript reports similar results of those reported by the work indicated from 2 out of 3 reviewers: Leta Hailu, Fantaw Yimer, Teklu Erkossa, 2020. Evaluation of the effectiveness of level soil bund and soil bund age on selected soil physicochemical properties in Somodo Watershed, Jimma Zone, SouthWestern Ethiopia J. Degrade. Min. Land Manage., pp. 2491-2502 DOI https://doi.org/10.15243/jdmlm.2020.081.2491

In the article in "Journal of Degraded and Mining Lands Management" wide parts of the abstract are identical to the present ms. In the cover letter, you specified <<I confirm that this work is original and has not been published elsewhere, nor is it currently under consideration for publication elsewhere>>. I wish to pinpoint that Plos1 consider the acceptance of a ms as a research article without taking into account its novelty and potential impact, upon that the methods are correct. However, Plos1 does not allow to publish data already published in other journals and the present data seems to derive from another articles, with a computation of stock.

In the Hailu et al. J. Degrade. Min. Land Manage article, you seem to show the data on SOC and STN concentrations (and other soil traits) at varying the age of soil bund (0, 3, 6 years), whereas in the present ms in Plos1 you show the SOC and STN stocks at varying the time of soil bund (3 or 6 year, in tab 1 and 2, respectively) while varying the presence of not of conservative management practices in apparently similar zones and layers than the previous. Data on the farms without the conservation measure in tab 1 and 2 are the same and may be derived from the data at 0 years of soil bunds. Lastly, data of tab. 3 are the same of those shown in tab 1 and 2 relative to the conservation measures.

Also, it sounds quite strange to me that here in this ms you don’t cite the former article, that was published before the submission of the present ms, whom results would help you discussing these ones.

It seems thus that the data on a stock basis in the present manuscript may derive from the ones of the former article, thus invite you to revise the present ms and clearly indicate the differences between the article in the J. Degrade. Min. Land Manage and the present one. Also, please carefully take into account the reviewer’s suggestions.

Lastly, I invite you to clearly diversify the previous article from the present ms. Wide parts of the materials and methods may be shared, but not of the other sections. In addition, data should not be replicated within the ms, so that just 1 table is enough.

In addition, tab. 4 is useless. You can just report the one number (R=0.86) in the main text.

Finally, if the data on the Stocks you are reporting derive from the previous work, this should be spelled out and cited in the abstract of the present work, given that stock directly derive from a computation from the concentration, bulk density and depth, all of which can be found in your previous ms. Finally, please indicate if the computation of the stock take into account of the coarse fraction, if any.

Please mind that decision to allow you to opt for a revision is not a pre-requisite for the acceptance of the ms as a research article.  

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Partly

Reviewer #3: Partly

**********

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: I Don't Know

Reviewer #3: Yes

**********

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: No

Reviewer #2: No

Reviewer #3: No

**********

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: No

Reviewer #3: Yes

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Review report

Manuscript Number: PONE-D-20-35754 “Comparison of soil organic carbon and total nitrogen stocks between farmland treated with level soil bund of different age and adjacent farmland without conservation measure: in the case of southwestern Ethiopia”

The manuscript addresses a subject of current interest related to the effect of level soil bund (aged 3 and 6 years) an) on Soil organic carbon and total nitrogen Stocks compared to a control farmland. Overall, I do like this paper, but the novelty and potential for impact are somewhat limited. I here encourage the authors to revise the paper.

Some suggestions for further improvement are given below:

1. The paper is written in poor English. There are many grammar mistakes and some sentences that are not easily understood. A very careful and intensive revision by a native speaker is necessary.

2. The title corresponds to the text. However, it has to be redone and reformulated.

3. The authors must pay attention to the abbreviation. Try to use the same abbreviation. Please specify if the values are for SOC or TN amount or for the stocks .

Abstract section

4. Line 22 : “The result indicated that farmland treated with LSB of 6 years has insignificantly higher SOC (102.57±9.00 Mg ha-1) and TN (9.74±0.9 Mg ha-1) than farmland treated with LSB of 3 years (98.42±10.24 Mg ha-1).” It is preferable that the authors add the value of TN for LSB of 3 years for a better comprehension.

5. Line 26 :“Similarly, farmland treated with LSB of 6 years was sequestered more 5.20% % of SOC ..” Please delete the double symbol %.

Introduction section

6. The introduction should be developed. , there are many researches related to this problematic have been done. It would benefit of more detail and supported with the related references.

7. Line 48 :“In addition, important terrain like a slope, aspect and soil types...” Slope, aspect and soil types are considered like factors or parameters not terrain.

8. Line 58 “ Similarly, fields treated with soil and water conservation practices were founded the lower mean bulk density than the untreated fields in Adaa Berga district, western Ethiopia [15].” Please rephrase appropriately

Materials and methods section

9. Description of the study area, line 86 :“ 7°46’’00’N-7°47’’00’N latitude and 36°44’’10’E-36°46’’50’E longitude (Fig 1).” These coordinates system does not correspond to the Fig 1.

10. Figure 2 : On the axis of temperature please add the unit and delete “Max. And Min.” because it is defined on the legend.

11. Research design and soil sampling, line 103-106 and line 107-112 : Please rephrase appropriately to avoid redundancy.

12. Research design and soil sampling, line 115 “Finally, SOC (Mg ha-1) and TN (Mg ha-1) were calculated….” Please specify that it is SOC and TN stocks.

13. Research design and soil sampling, line 112-117 “The collected soil samples were transported to Jimma Agricultural Research Centre laboratory … bulk density (g/cm3), and layer thickness (cm).” The authors should move this paragraph in the laboratory analysis section.

14. The authors must improve the table 1, 2 and 3 : Specify that the values are for SOC and TN stocks as l mentioned before. Also, please try to be brief when writing the name of x-axis, it could be SOC stock LSB-3 years / LSB-6years/ Control.

Results and discussion section

15. The authors showed that total nitrogen, organic carbon and bulk density were used in this paper, but in the results and discussion section, why it was not included? The authors should add these data to this section using a table.

16. Line 149 : TOC and TN data can not completely represent soil organic matter content. As fields treated with above three years’ soil and water conservation measures had higher organic matter accumulation as compared to the non-conserved fields. The data of OM would be more accurate.

17. Figure 3: Please specify that the values are for SOC stocks, on the y-axis and for the legend. Same as I mentioned below, try to write briefly, instead of writing “farmland with three years LSB” The authors can just write LSB-3years and Control.

18. Line 202-204 :“The top layer accounted for 52% of the TN in the upper bund zone of farmland treated with six years aged LSB and 51% of the TN in adjacent upper zone of farmland without conservation measures.” Please provide explanation how the authors get these values?

19. Line 228 “The upper, middle and lower bund zones of SOC stocks in farmland treated with six years LSB was approximately 10.5%, 10.3% and 10.3% higher than the upper, middle and lower bund zones of farmland treated with three years LSB, respectively.” Please explain how the authors get these values?

20. For table 4: The Pearson`s correlation matrix for soil organic carbon and total Nitrogen, is it for the stocks values ?

21. References: Please be sure that all the references cited in the manuscript are also included in the reference list and vice versa with matching spellings and dates and according to the journal format, "Instructions for Authors".

Looking forward for your positive consideration of these comments.

Regards,

Reviewer of the manuscript

Reviewer #2: The Hailu & Betemariyam manuscript compares organic carbon and total nitrogen stocks as critically important soil quality parameters in farmland treated with 3 and 6 years aged level soil bund and adjacent farmland without conservation measures. The results section is divided into three subsections, but due to a data repetition in each subsection please consider a possibility to construct the results section comparing all 3 treatments in one table, if it`s possible to present data of statistical analysis this way.

Data Availability Statement in the manuscript PDF file is Yes, but there is no information where the data may be found.

Add information to Research design section about the soil you were studied: Was it Nitisol or Acrisol?, What is the clay content in it?, etc. Is a sampling site on adjacent farmland without conservation measures representative? Was it the same soil type? Which type of crops were grown on adjacent farmland?

Consider adding initial data (bulk density and content of organic carbon and total nitrogen in the soil) to the results section. This will give additional information to understand the reasons for your findings.

Other than that there were the following minor observations:

Laboratory analyses. Line 120: Walkley and black (use Upper case)

P. 7 Line 172: Text is about TN stocks but the reference is to a figure about SOC stocks (Fig. 3). Delete this reference and insert Figure 3 after Line 154.

Conclusions. Line 261: Finally, it could be concluded that… Avoid “enormous amounts of SOC and TN” because as you`ve found the mean difference in SOC and TN stocks is not significant between 3-years aged LSB and non-treated farmland. To conclude “considerable role in mitigating climate change by sequestering corresponding greenhouse gases” research findings do not seem to be completely enough.

Fig. 3: Delete “a” and “b” symbols in the figure?

Fig. 3 and tables: Round off numbers to 2 decimal places

Consider language editing to make some sentences more easily understandable

Reviewer #3: Dear Authors, unfortunately, the manuscript seems very similar to a previous research published form the same or almost the same Authors. I cannot discuss about the quality if a similar experiment is already published "" ext-link-type="uri" xlink:type="simple">https://jdmlm.ub.ac.id/index.php/jdmlm/article/view/751".

I would be pleased to be invited to revise other research of yours, the topic is sound and actual.

Please try to provide a systematic literature search before to do any experiment, it might be useful perform a more comprehensive search with a structured query in a citation and abstract database such as Scopus or Web of Knowledge, as it was carried out in Modelling of Soil Organic Carbon in the Mediterranean area: a systematic map November 2018Rendiconti Online Societa Geologica Italiana 46/2018 DOI: 10.3301/ROL.2018.68

I suggest to read also other systematic map applications to improve the state of the art writing style.

Kind regards

**********

6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

Reviewer #3: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

PONE-D-20-35754R1

Comparison of soil organic carbon and total nitrogen stocks between farmland treated with three and six years level soil bund and adjacent farmland without conservation measure: in the case of southwestern Ethiopia

PLOS ONE

Dear Dr. Gemechu,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by May 26 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-emailutm_source=authorlettersutm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Sergio Saia, Ph.D.

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

Reviewer #3: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Partly

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: I Don't Know

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Review report

Manuscript Number: PONE-D-20-35754 “Comparison of soil organic carbon and total nitrogen stocks between farmland treated with level soil bund of different age and adjacent farmland without conservation measure: in the case of southwestern Ethiopia”

The manuscript addresses a subject of current interest related to the effect of level soil bund (aged 3 and 6 years) on Soil organic carbon and total nitrogen Stocks compared to a control farmland. Overall, I do like this paper, but the novelty and potential for impact are somewhat limited. I here encourage the authors to revise the paper.

In overall I fell the study can be suitable for publication in PLOS ONE after minor revision. Some suggestions for further improvement are given below and other are reported in attached word file:

Abstract

Line24-25: the authors said ‘’With respect to the age of LSB, farmland treated with LSB-6 years accumulated more 2.83% SOC stock than control.”

If they are comparing the overall mean of LSB-6 year to control, normally the corrected value will be 5.83% not 2.83%. Please check it

Results and discussion section

Line 203-205 : the authors said that ‘’ The overall mean value of LSB-6 years has exhibited higher mean value of SOC at the lower bund zone (97.81±10.49 Mg ha-1) as compared to LSB-3 years (94.37±7.65 Mg ha-1) (Table 1).’’

Or LSB-6 year exhibited more SOC stock at the lower and middle bund zone.

Line 208-211: the authors said “TN socks did not show significant difference (p0.05) between all inter bund zones. However, under all bund zones, the TN stock showed higher overall mean value under LSB-6 years (9.44±1.57 Mg ha-1) than LSB-3 years (9.28±1.60 Mg ha-1) (Table 1). Similar results were reported by [26] in Zikre watershed, Adaa Berga district. “

But for LSB-6 year, the TN stock is 9.37±1.10 Mg ha-1 and for the LSB-3 year is 9.44±1.57 Mg ha-1. In this case TN stock showed higher mean under LSB-3 year as compared to LSB-6 year.

Looking forward for your positive consideration of these comments.

Regards,

Reviewer of the manuscript

Reviewer #2: Here some suggestion to improve the manuscript:

1) Lines 139-140 “inter-bund zone …” use the same terminology that you use in the Results section: (upper, middle and lower) instead of (loss, middle and deposition)

2) In line 144 “and the same size undisturbed soil samples were collected for bulk density determination” do not repeat 141-142 lines “Similar sample sizes of undisturbed soil were also collected for bulk density determination using core sampler”, just use “bulk density determination”

3) Line 154: bulk density (g/cm3) (use superscript)

4) In table 1 do not repeat “SOC stock of/ TN stock of”. Write it only once at the top line of the table and indicate below: “control, LSB-3 years, LSB-6 years”

5) Lines 259-260: “this contribute in mitigating climate change…” According to obtained results it’s better to conclude the deposition of carbon and nitrogen than their sequestering (from the atmosphere). So, I suggest to write “by preventing erosion-induced greenhouse gases emission into the atmosphere” instead of “by sequestering corresponding greenhouse gases”

Reviewer #3: Dear Authors

I read the revised version of the manuscript “Comparison of soil organic carbon and total nitrogen stocks between farmland treated with level soil bund of different age and adjacent farmland without conservation measure: in the case of southwestern Ethiopia” I have seen some improvement and I think the paper can be revised again and go ahead in the publishing process, but please amend all the things listed below and the other review request. Reviewers suggested many things to improved your manuscript much than I have done due to the similarity with your previous unacknowledged research about SOC % with the same experimental settings. The experimental setting is decent, the authors can bring more evidences about the study area and they can translate the effect found in the trial in order to give a practical benefit addressed to the local policy makers.

The manuscript is proposed as a research article, due to the length (3200 words) the similarity with the previous study (shared experimental settings) of the same work of the authors about SOC %, and the limited novelty, I think it can be proposed as a short communication, a normal research article is made by approximately 6000 works, although I found normal manuscript of 8000 words.

Line24-25: Please check it ‘’With respect to the age of LSB, farmland treated with LSB-6 years accumulated more 2.83% SOC stock than control.” It should be around 5.83%?

Terminology must be consistent throughout the manuscript (e.g. lines 139-140 inter-bund zone), please check the consistency

I would rephrase the sentence “by sequestering corresponding greenhouse gases” in something more neutral.

Please define better the conclusion of the experiment. Do not oversell the findings.

Why not include the authors who revised the manuscript? They must be capable to understand the problem to check the language. I do not know in what extend they were involved in the research activities but in case they were, they must be rewarded.

Kind regards

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

Reviewer #3: Yes: Calogero Schillaci

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Attachments

Attachment

Submitted filename: Manuscript_Rev_A.doc

Comparison of soil organic carbon and total nitrogen stocks between farmland treated with three and six years level soil bund and adjacent farmland without conservation measure: in the case of southwestern Ethiopia

PONE-D-20-35754R2

Dear Dr. Gemechu,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Sergio Saia, Ph.D.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments: