Study of a New Photocatalytic Film Process Combined with a Constructed Wetland and an Analysis of Reoxygenation Pathways in a Water Body

Round 1

Reviewer 1 Report

This manuscript reported a new process of photocatalytic film combined with constructed wetland and analysis of reoxygenation pathway in water body. The bacterial species and abundance in the lake water treated by the PF&WIC changed significantly. This manuscript is succinctly described. There are some issues that should be noticed and addressed before publication.

 1. The author should perform some physical and chemical characterizations of the photocatalytic film and provide relevant analysis and explanation with regards to its performance.

 2. The possible mechanisms of catalytic films for removing pollution can be presented in the manuscript. The author can refer to similar illustrations of active antifouling and passive antifouling in Adv. Mater. 2023, 35, 2306626 to explain possible mechanisms.

 3. The research methods and processes can be drawn into a scheme.

 4. Can significant digits be precise to two decimal places, such as 79.08% in the conclusion? Suggest reducing one; 79.1%.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript (sustainability-2932383) titled with “Study of a new process of photocatalytic film combined with constructed wetland and analysis of reoxygenation pathway in water body” further investigated the effectiveness of the process that using photocatalytic film as the front-end treatment of a composite iron-carbon constructed wetland (PF&WIC) for the restoration of mildly eutrophic water body. The work is valuable for treating eutrophic water bodies. In consequence, I recommend accepting it after careful modification. However, the following issues should be considered and discussed in the manuscript.

The recommendations are given below:

1.      Lines 45-46: In the introduction section, the authors mentioned that “constructed wetland technology is one of the commonly used water treatment technologies”. The reasons for choosing constructed wetland technology should be explained.

2.      The novelty of this study should be inserted in the text clearly.

3.      In the part 2.1, “The water source was from a small, mildly eutrophic lake on the campus of Fuzhou University's Qishan Campus”, multiple samples should be taken at different times and locations to make the samples more generalizable.

4.      Lines 45-46: “the role of Fe-C microelectrolysis in W_IC plays a dominant role for N removal throughout the treatment process”, the inference necessitate a more comprehensive elucidation.

5.      Lines 148-185: “Fe²⁺ and Fe³⁺ produced by Fe-C microelectrolysis are the key to P removal”, more detailed explanation and clarification are needed.

6.      The specific role of Fe-C microelectrolysis should be explained in detail.

7.      The conclusion should be improved with clear quantitative findings.

Minor editing of English language required.

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Water eutrophication is common problem in natural water, especially sources of drinking and industrial one. Presented technology is new and presented results valuable but addition of some information and corrected results presentation.

My suggestions to changes:

-      The Table S1 and Figure S1 should be added to the main text, on the other hand Table S2 are useless, please removal it

-      Is necessary to present  test implementation in more detail, especially how many times the test was repeated, methods of water quality parameter analysis

-      All results were compared to the one other research results (one reference), in my opinion is not enough. The discussion of research should be develop.

-      The results of research will be present in more detail. For example the statement  “The water body needs to go through a three-stage treatment of PF, VSSFCW and HSSFCW before most of the TP can be removed, and PF has a very limited ability to remove TP and should not be used alone for P removal.” Should be supported by deeper analysis of results.

It concerns all water quality parameters not only TP.

-      Figures 8 and 9 are unreadable

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The questions have been modified by the authors.

Minor editing of English language required.

Reviewer 3 Report

Author corrected paper according my suggestions.