PONE-D-24-03564Characterization of methane microseepage from natural gas reservoirs in mild climate: a case study of Xinchang gas fieldPLOS ONE

Dear Dr. Wang,

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.

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We look forward to receiving your revised manuscript.

Kind regards,

Trung Quang Nguyen

Academic Editor

PLOS ONE

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Hangzhou Dianzi University (Grants No. KYS205622065)."

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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: Yes

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

Reviewer #1: Yes

Reviewer #2: 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: Yes

Reviewer #2: Yes

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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: Yes

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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: This document provides additional comments and considerations for the manuscript titled "Characterization of methane microseepage from natural gas reservoirs in mild climate: a case study of Xinchang gas field." The comments focus on potential concerns regarding duplicate publication, research ethics, and publication ethics.

Duplicate Publication: There is no indication that the results presented have been published elsewhere, which is positive. However, the authors should explicitly clarify if any part of the work, including data, figures, or substantial portions of the text, has been or is under consideration for publication in another venue. This clarification is essential to avoid issues of self-plagiarism and duplicate publication.

Research Ethics: The methodology section provides detailed information on data collection and analysis. Nonetheless, it would enhance the manuscript's integrity if the authors included a statement on ethical considerations, especially regarding environmental impact assessments of the study area. Given the environmental sensitivity of methane emissions, outlining measures taken to minimize potential harm or disturbance during the study would be beneficial.

Publication Ethics: The manuscript should adhere to high standards of publication ethics, including full transparency about the contributions of each author and the disclosure of any potential conflicts of interest. While the manuscript includes funding information, a more detailed statement regarding the authors' adherence to ethical guidelines in conducting and reporting their research is recommended.

In conclusion, while the study presents valuable insights into methane microseepage from natural gas reservoirs in a mild climate, addressing the above concerns can significantly strengthen the manuscript. Ensuring clarity on these aspects would enhance the manuscript's contribution to the field and its ethical and scientific rigor.

The study on "Characterization of methane microseepage from natural gas reservoirs in mild climate: a case study of Xinchang gas field" provides significant insights into methane emissions and their implications for climate change. The comprehensive analysis of methane flux, hydrocarbon composition, and carbon isotope profiles in the Xinchang gas field is commendable for its depth and detail. Here are some additional comments and suggestions for further strengthening your manuscript:

Integration with Global Data: While your study provides critical data on methane microseepage in the Xinchang gas field, integrating these findings with global datasets on methane emissions could offer a broader perspective on the significance of your results. Comparing your data with methane flux measurements from different geological settings worldwide could contextualize the unique aspects of methane microseepage in mild climates.

Methodological Advancements: Your methodology, combining field measurements and laboratory analysis, is robust. However, discussing any potential limitations of your techniques and how they compare with other contemporary methods could enhance the reliability of your findings. For instance, detailing the calibration process of the greenhouse gas analyzer and static gas collection chambers could provide clarity on the accuracy of your measurements.

Microbial Activity Analysis: Given the significant role of microbial activities in methane consumption, a more detailed analysis of the microbial communities present in the soil samples could provide insights into the biodegradation processes affecting methane flux. This could involve genomic or metagenomic analyses to identify methanotrophic communities and their functional capabilities.

Impact of Climate Change: Considering the implications of methane on climate change, an analysis of how future climate scenarios might affect methane microseepage patterns in the Xinchang gas field and similar environments would be valuable. This could involve modeling studies to predict changes in methane flux under various climate change projections.

Policy and Management Implications: Expanding the discussion on the implications of your findings for methane management and climate change mitigation policies could make your study more impactful. Suggestions for policy interventions or management strategies to mitigate methane emissions from natural gas reservoirs could provide practical value to your research.

Longitudinal Studies: Mentioning the potential for longitudinal studies to observe changes in methane microseepage over time, especially in the context of ongoing climate change and human interventions in natural gas fields, could highlight the importance of continued research in this area.

These comments are intended to complement the strengths of your manuscript and suggest avenues for further enhancement. Your research contributes significantly to our understanding of methane emissions from natural gas reservoirs and their climate implications, highlighting the need for comprehensive monitoring and management strategies.

Reviewer #2: Please double check the manuscript and revise it carefull before re-submit to the Journal:

- The Section 2. Geological 76 Settings of Xinchang Gas Field should be included in the Section 1. Introduction.

- The Section 3.2. Laboratory Analysis should be cited some references for the methods used

- Please update the reference to papers published in the last 5 years.

- There are several DOI does not work, please check for any error in the links.

- Some references without DOI, which should be added; and some references were listed with Capital character: Ex. Ref 17, 19…

- The conclusion section should not separate into different paragraphs as in the present manuscript version.

- This phrase should not use in the conclusion section: “The results are consistent with previous studies…”.

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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

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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: Comments.docx

PONE-D-24-03564R1Characterization of methane microseepage from natural gas reservoirs in mild climate: a case study of Xinchang gas fieldPLOS ONE

Dear Dr. Wang,

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 Sep 28 2024 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: https://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-email&utm_source=authorletters&utm_campaign=protocols .

We look forward to receiving your revised manuscript.

Kind regards,

Trung Quang Nguyen

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.

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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 #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 #3: Yes

**********

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

Reviewer #1: Yes

Reviewer #3: Yes

**********

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 #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 #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: The author's response to the feedback provided in the initial review demonstrates a commendable effort to address the reviewers' concerns and significantly improve the manuscript. The revisions made, particularly in the methodological section and the integration of additional references, have enhanced the scientific rigor of the study. The addition of a detailed comparison with global datasets on methane emissions strengthens the contextualization of the study's findings, allowing for a broader application of the results. Furthermore, the clarification regarding ethical considerations and environmental impacts contributes to the transparency and credibility of the research. The response to the suggestions on the microbial activity analysis and the potential impacts of climate change reflects a thoughtful approach to acknowledging the study's limitations while outlining future research directions. The restructuring of certain sections and the refinement of the conclusion have improved the manuscript's overall coherence and clarity. In summary, the authors have successfully addressed the critical points raised, resulting in a more robust and scientifically sound manuscript that makes a valuable contribution to the field.

Reviewer #3: I would advise authors to mention some recommendations at the end of both abstract and conclusion based on the results of this study regarding current and future practices in the subjects of this study.

**********

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 #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.

Attachments

Attachment

Submitted filename: Review of PONE-D-24-03564R1.pdf

PONE-D-24-03564R2Characterization of methane microseepage from natural gas reservoirs in mild climate: a case study of Xinchang gas fieldPLOS ONE

Dear Dr. Wang,

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 Nov 02 2024 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: https://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-email&utm_source=authorletters&utm_campaign=protocols .

We look forward to receiving your revised manuscript.

Kind regards,

Trung Quang Nguyen

Academic Editor

PLOS ONE

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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

**********

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

**********

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

Reviewer #1: Yes

**********

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

**********

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

**********

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: The study on methane microseepage from the Xinchang gas field provides valuable insights into geological methane emissions in mild climates. The methodology, including soil sampling and methane flux monitoring, is thorough and appropriate for identifying geochemical anomalies and migration patterns. However, the paper could improve its discussion on the limitations of the study, particularly regarding the impact of local climate variability on methane flux. The absence of long-term monitoring limits the understanding of temporal variations in microseepage. Additionally, the discussion could further explore the role of microbial activity in methane oxidation, which may significantly influence surface flux measurements. Furthermore, while the use of static gas collection chambers is common, complementing these measurements with remote sensing data could enhance spatial coverage and detection sensitivity. The study's findings align with existing literature, yet it would be beneficial to compare the results with regions having different climatic conditions to provide a more comprehensive understanding of methane microseepage behavior.

Questions:

1. How might seasonal variations in temperature and precipitation affect methane microseepage in the Xinchang gas field?

2. What are the potential biases introduced by short-term methane flux measurements, and how can they be mitigated?

3. How could the integration of remote sensing techniques improve the detection of methane microseepage compared to traditional methods?

4. In what ways does microbial activity in soil influence the measurement of methane flux, and how was this accounted for in the study?

5. How do the results from the Xinchang gas field compare to other regions with different geological or climatic conditions?

**********

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

**********

[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-24-03564R3Characterization of methane microseepage from natural gas reservoirs in mild climate: a case study of Xinchang gas fieldPLOS ONE

Dear Dr. Wang,

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 Dec 16 2024 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: https://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-email&utm_source=authorletters&utm_campaign=protocols .

We look forward to receiving your revised manuscript.

Kind regards,

Trung Quang Nguyen

Academic Editor

PLOS ONE

[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

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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

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

Reviewer #1: Yes

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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

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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

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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:  The manuscript titled "Characterization of methane microseepage from natural gas reservoirs in mild climate: a case study of Xinchang gas field" provides a thorough investigation into the contribution of methane microseepage to atmospheric methane, a critical greenhouse gas. The study employs a combination of soil sampling, methane flux monitoring, and geochemical analysis to explore methane migration patterns and origin tracing. The use of acid-hydrolyzed hydrocarbons (AHH) and altered carbonates (AC) to identify geochemical anomalies is well-established, and the methodology aligns with previous studies, adding to the body of knowledge on geological methane emissions in mild climates. However, the study could benefit from a more in-depth discussion of the limitations related to short-term flux measurements and the potential biases introduced by local climate conditions.

One of the study's strengths is its comprehensive use of isotopic analysis to distinguish thermogenic methane from biogenic sources, reinforcing the findings on methane origin. Nonetheless, the absence of long-term monitoring limits the study's ability to assess temporal variations in methane flux, which could be significant given the dynamic nature of methane emissions. Furthermore, while microbial activity's influence on methane flux is acknowledged, more detailed analysis of its role in the study area would enhance the discussion.

This study contributes valuable data to the understanding of methane microseepage in mild climates but would benefit from addressing the identified limitations and considering the potential for integrating remote sensing techniques to improve methane detection.

Questions:

1. How could long-term monitoring influence the understanding of methane flux variations in the Xinchang gas field?

2. What specific factors related to local climate conditions could introduce biases in short-term methane flux measurements?

3. How do microbial activities specifically impact methane flux measurements in mild climates like the Xinchang gas field?

4. Could integrating remote sensing methods with in-situ monitoring provide a more comprehensive picture of methane microseepage?

5. How do the methane flux measurements in the Xinchang gas field compare with those from regions with more extreme climatic conditions?

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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

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Characterization of methane microseepage from natural gas reservoirs in mild climate: a case study of Xinchang gas field

PONE-D-24-03564R4

Dear Dr. Haoqi Wang,

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.

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Kind regards,

Trung Quang Nguyen

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

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

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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

**********

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

Reviewer #1: Yes

**********

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

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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

**********

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: The authors have addressed the reviewers' comments comprehensively, significantly improving the manuscript's clarity, methodological rigor, and scientific contribution. The study provides a thorough investigation into methane microseepage from natural gas reservoirs, exemplified by the Xinchang gas field. The incorporation of new analyses and detailed discussions enhances the manuscript’s value.

First, the revised manuscript includes an expanded discussion on the influence of climate and microbial activity on methane flux measurements. This addition effectively contextualizes the study within broader climatic and biological frameworks, providing insights into the variability of methane emissions under different environmental conditions. Furthermore, the authors have clarified the methodological approach, particularly the integration of static gas chambers and isotopic analyses, which ensures the robustness of the methane flux measurements.

The response to comments regarding long-term monitoring and remote sensing integration demonstrates the authors' commitment to addressing methodological limitations. Their acknowledgment of spatial and temporal variability in methane flux and the potential for remote sensing to complement in-situ measurements reflects a well-rounded and forward-looking perspective.

Moreover, the comparison between Xinchang and other global sites enriches the discussion, highlighting the uniqueness of the observed patterns in mild climates and their implications for geological methane management. The authors also appropriately emphasize the need for continued research into the complex interactions of geological, climatic, and microbial factors influencing methane emissions.

The conclusions are well-supported by the results, particularly the identification of methane release patterns and the confirmation of thermogenic origins through isotopic analyses. These findings are not only relevant to the Xinchang gas field but also provide valuable insights for managing methane microseepage in similar geological settings globally.

Therefore, the authors have significantly improved the manuscript, addressing all major concerns and enhancing the scientific quality and clarity of their work. The study is now suitable for publication and will contribute meaningfully to the understanding and management of geological methane emissions

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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

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