A Modified Fick’s First Law Incorporating a Flux Correction Factor for Nutrient Diffusion in Intertidal Sediments
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsTitle: Nutrient Diffusion in Intertidal Sediments Requires Amending Fick’s First Law of Diffusion to Include a Flux Correction Factor and Assess Vertical Nutrient Flux
The manuscript addresses an important and novel problem in sediment biogeochemistry and nutrient flux in intertidal pore water. The work is original, field-based, and methodologically rigorous, combining field measurements with theoretical modification and statistical validation. However, the manuscript has some weaknesses in terms of clarity, interpretation of results, and linkage to ecological implications. The contribution is potentially valuable, but revisions are needed to strengthen presentation and justification.
Comments
Line 6: I have suggested to the author that they include the country name in the affiliations.
Line 12: Where exactly were the study sites located? Which coast/region? What period of sampling was carried out?
Line 12: Various depths mean? Give the detailed depth measurement.
Line 24: Change “on one hand … on the other hand”
Line 89: Porewater to be Pore water
Figure 1 shows that the sampling location was in only one transect. How does the one sampling transect reflect the whole wetland area?
Line 100: How does the modified Fick’s First Law differ from the classical Fick’s First Law in describing nutrient diffusion? What specific modifications were introduced to Fick’s First Law, and how do these changes improve the description of nutrient diffusion in intertidal sediments?
Ensure consistency in units (µmol/m²/day) and ion formatting (NH₄⁺, NO₃⁻, PO₄³⁻).
Why is upward flux dominant across stations? Could this be an artifact of sampling or sediment characteristics (e.g., organic matter degradation, redox conditions)?
Improve readability of flux plots (Figures 6–8). Consider adding error bars or confidence intervals to support statistical claims.
Flux correction factor plots (Figure 5) should include clear labels and scales.
NH₄⁺flux shows no statistically significant difference between standard and modified laws (p > 0.05). Does this indicate that the modification is unnecessary for NH₄⁺ transport?
To enhance the overall quality of the figures.
Recommendation
The study presents an innovative approach to refining nutrient flux estimation in intertidal sediments. However, the modest correction effect, limited statistical significance, and overreliance on mathematical fitting raise concerns about its broader impact. I recommend major revisions before this manuscript can be considered for publication.
Author Response
Please see the attachment below.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe manuscript is interesting, but it needs to be improved and revised for publication.
1. What are the limitations of the approach used?
Are there conditions under which the modification of Fick's law to account for the activity coefficient might be less effective?
2. Can the proposed model be applied to other types of sediments or water bodies?
3. Lines 60-72 should not be included in the introduction.
4. Please reword the last paragraph of the introduction and write it in a positive form, not a question.
5. All the figures provided are illegible and of poor quality. They should be corrected.
6. Please include a separate section on the statistical analysis.
This should be corrected.
Author Response
Please see the attachment below.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsDear Editor,
Thank you for your invitation to review the manuscript in Water Journal. Hereby, I state that the manuscript has been accepted for publication in the present form. The authors have carried out all the comments suggested by the reviewer. I am satisfied with the revised manuscript.
