Using ¹⁵N Isotope to Evaluate the Effect of Brown Coal Application on the Nitrogen Fate in the Soil–Plant System

Round 1

Reviewer 1 Report

Lei and co-authors, studies the effects of brown coal application on the nitrogen fate of pakchoi. I think the paper is clear and well-presented, the argumentation is easy to follow. The results are very detailed and they are also well-presented and fully explained. The discussion ends with a well-balanced appreciation of the limitations of the study. However, in my opinion several significant items remain to be addressed before publication.

L14-31, The abstract is very long, but lacking a focus. There are too many results, but I don't know which one is your key result.

Line 31, where is your conclusion. You may need a more informative conclusion and implication here. It is unclear what are your main conclusions. You may need some specific conclusions and implications based on your key results.

L46-52, since it’s the first paragraph of the introduction the authors should take the time to explain why the N or coal application is important.

L80-87, The research questions and hypotheses can be strengthened from the introduction.

L174-204, You need more efforts for the results section to well focus on your key findings. This can make your results clearer.

Discussion: From main result from the authors should discuss their implication and limitations.

L572-580, Too many good results may weaken your key results and conclusions.

Author Response

Please refer to the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

This manuscript is reasonably good and presents interesting data on nitrogen management. But the manuscript needs to be revised before final acceptance. Some observations are listed below.

 

1.Explain in detail how per hectare nutrients are applied and describe the recommended nutrient dose for the investigated crop.

2.Highlighted the chemical composition of brown coal with respect to nutrient properties.

3.The plant population in a pot is also not described in order to comprehend the nutrients utilization.

4.What is the rationale for using higher nitrogen levels even though the crop is short-lived and grown in pot culture. Explain why the difference between consecutive doses is kept at 100 times. 

5.The study was conducted in a single season and under pot conditions; how are these results related to field conditions? 

6.The long-term application of BC can be good practice, but at the same time it has required more amounts of nitrogen to maintain the optimal CN ratio. justified the hypothesis of BC application.

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 3 Report

see the attached file.

Comments for author File: Comments.docx

Author Response

请参阅附件

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The authors significantly improved the paper, the story is well-structured. The authors did a good job addressing the previous comments and the manuscript can be accepted for publication, but there are still some remaining in the manuscript that needs to be clarified as below shown.

 

1.       Notes should be added to abbreviations of all figs and tables.

2.       The methods of Fig. 7 is missing.

3.       L24, In conclusion, ……

4.       L58-59 soil microbial activity also affects the stoichiometry, nutrient limitation, and N cycling.

See relevant papers, Xu et al., 2022, Soil Biology and Biochemistry, 170, 108714. https://doi.org/10.1016/j.soilbio.2022.108714. Xu et al., 2022, Science of the Total Environment, 810, 152286. http://dx.doi.org/10.1016/j.scitotenv.2021.152286.

Author Response

Please see the attachment

Author Response File: Author Response.docx