Effect of Eutrophication Control Methods on the Generation of Greenhouse Carbon Gases in Sediment

Round 1

Reviewer 1 Report

This study itself is interesting and has a certain impact in this area. However, the description needs to be re-arranged. More importantly, the experimental design is lack rigour, which leads the unreliable results in order to extrapolate to the real scenario. Here are the comments,

1. The introduction section was clearly divided into two sections, i.e. GHG emission and nutrient load control. In the end, the authors tried to link them together, however, the novelty, knowledge gaps, and the hypothesis are missing. Those aspects should be the key info that authors should focus on.
2. L124, the authors mentioned that ‘the study area is the Valle de Bravo reservoir’, which is not true. The experiment was a lab-scale simulated study. The background of the site where sediment/water was taken should be simplified and moved to the M&M section.
3. The selection of the treatments is doubtful. As we can see from the experimental setup, the diffuser was embedded into the sediment which could lead to significant disturbance of the SWI while operating the aeration process. Previous studies have developed advanced oxygenation strategy, see Zhang et al., 2021 (DOI: 10.1016/j.cej.2020.12720), Tang et al., 2021 (DOI: 10.1016/j.watres.2021.11), Zhang et al., 2018 (DOI: 1016/j.scitotenv.2018.04.284). The reason for not choosing such state-of-the-art technology should be discussed.
4. Moreover, the application of Phosloc has been reported to result in some negative effects on the aquatic environment. Other simple and safe materials, such as coal fly ash based adsorbents (DOI: 10.1016/j.chemosphere.2021.132431), and advanced synthetic adsorbents (DOI: 10.1016/j.scitotenv.2020.138424) have been reported. The relevant info should be discussed as well.
5. Another critical issue is the experimental design, the current reactor was operated without headspace. It means the authors artificially create an anoxic/anaerobic condition for the water/sediment system. The top-open reactors should be operated for the study.
6. There are quite a few format issues and typos in the paper: i.e. GHCG – should be GHG, L77, cameras? L191-200 the content should be in a table, the unit of mmol/m2 for carbon mass balances is strange.
7. The majority of the results do not have standard errors and miss the result of statistical analysis.

Author Response

Dear Reviewer

The reply to each of  your comments  is here in the following document. 
Also, the revised manuscript includes corrections to each of the comments received from three reviewers

Thanks you, kind regard

Author Response File: Author Response.docx

Reviewer 2 Report

The title of the article does not correspond to the main content of the work. This is related to the fact that in the Introduction is not clearly stated what is the main aim of the work. In the chapter Introduction are general statments about mineralization and about the GHG (green house gases) but no link to experiments and compounds measured. Thus it is neccesary to improve chapter introduction. 

There is sometimes not precise formulation for example raw 57 has to be improved. - the oxygen containing compounds are not just elements Mn, or Fe

The experiments are described very precisely but is not stated for example why the main aniont and cationt in water were not analyzed.

The chapter results and discussion is difficult to follow as there is not aim of the work thus from my point of view the conclusion is very week.

Author Response

Dear Reviewer

The reply to each of  your comments  is here in the following document. 
Also, the revised manuscript includes corrections to each of the comments received from three reviewers

Thanks you, kind regard

Author Response File: Author Response.docx

Reviewer 3 Report

There is so much information in the introduction section, but no clear mention of the objectives of the study.

The method section is too long, the repetition of text and ideas in the section.

The results and discussion section is very small. Only results are reported, no discussion.

Overall, the ms. is presented poorly.

Author Response

Dear Reviewer

The reply to each of  your comments  is here in the following document. 
Also, the revised manuscript includes corrections to each of the comments received from three reviewers

Thanks you, kind regard

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The current paper has been improved. However, here I still have one comment and believed it can be considered by the authors. Although the authors claimed that this paper does not focus on eutrophication control methods, however, the current title does not follow this statement. In order to improve the potential impact of the study, the previous recommended methods should be considered and discussed to support the future research needes.

Author Response

Dear reviewer,

Thank you for your suggestions, here attached the answers.

Kind regards,

Author Response File: Author Response.docx

Reviewer 2 Report

The current version of the text is very good. I recommend for publication.

Author Response

Dear reviewer,

Thank you for your approval.

Kind regards,