Multi-Tier Validation of a Macroscale Nitrogen Model for Groundwater Management in Watersheds Using Data from Different Monitoring Networks

Round 1

Reviewer 1 Report

This study aims to improve the accuracy of mathematical models of nitrogen movement for the purpose of groundwater management. The relevance of this study is beyond doubt. However, this work clearly underestimates its significance. The results shown in the work are of wide scientific interest. However, the authors, for some reason, narrow the scope of the study (I will explain in the comments). The work is well structured, but has a "one-sidedness".

1. Section 1 has a deep study of the research problem. However, the review shows overwhelmingly European scientists. However, this topic is widely studied in Canada, the USA and India. The author needs to supplement section 1 with a literature review by authors from other regions.

2. The author must indicate in which software products the models were created, the results of which are presented in the figures.

3. The article does not have a section "Conclusion".

4. The conducted research has a fairly wide application. For example, the works of Ukrainian colleagues doi:10.1109/ElConRus54750.2022.9755852 or doi:10.1109/ElConRus51938.2021.9396250 show the effect of nitrogen on equipment. Similar studies are demonstrated at https://doi.org/10.3390/w15040770. During the extraction of mineral water. I recommend authors to refer to these works.

Conclusion. The work is extremely interesting and scientifically substantiated. However, I believe that this study is not limited to Germany. And it may be useful to a wide range of readers.

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 2 Report

The article presents an extremely important issue from the economic and natural point of view - modeling the migration of nitrogen and its compounds in groundwater. This task is difficult because N is present in groundwater in organic and inorganic forms. Nitrogen is heavily used by organisms. Some N speciations are sorbed. In addition, changes between nitrogen speciations occur dynamically in the groundwater environment, which depends on temporary oxidation-reduction conditions.

The authors, fully aware of these difficulties, carried out a multi-stage validation process of the proposed model. The results of the validation were extensively discussed in Chapter 7. I found this part of the article extremely valuable.

In my opinion, the article is in line with the aims of the Water journal. The manuscript has been prepared with great care and I suggest that it be published in its present form.

Author Response

Thank you for your review and for your positive feedback on our paper. We appreciate your time and effort in evaluating our work. We are glad to hear that you found the paper to be acceptable in its current state.

While we value your opinion, we have considered the suggestions and comments made by other reviewers and believe that there are a few areas where further improvements can be made to enhance the overall quality and clarity of the paper. We would like to address these points in our revised submission.

Thank you once again for your time and support. We will submit the revised version of the paper by the given deadline.

Reviewer 3 Report

The paper is well-targeted and appropriate to the journal scope. The structure of the paper is clear and the writing style appropriate. Discussion is also of good standard with appropriate citations to support statements.

Author Response

Thank you for your review and for your positive feedback on our paper. We appreciate your time and effort in evaluating our work. We are glad to hear that you found the paper to be acceptable in its current state.

While we value your opinion, we have considered the suggestions and comments made by other reviewers and believe that there are a few areas where further improvements can be made to enhance the overall quality and clarity of the paper. We would like to address these points in our revised submission.

Thank you once again for your time and support. We will submit the revised version of the paper by the given deadline.

Round 2

Reviewer 1 Report

in general everything is fine